Xylitol for preventing acute otitis media in children up to 12 years of age.

PubMed

Azarpazhooh, Amir; Lawrence, Herenia P; Shah, Prakeshkumar S

2016-08-03

Acute otitis media (AOM) is the most common bacterial infection among young children in the United States. There are limitations and concerns over its treatment with antibiotics and surgery and so effective preventative measures are attractive. A potential preventative measure is xylitol, a natural sugar substitute that reduces the risk of dental decay. Xylitol can reduce the adherence of Streptococcus pneumoniae (S pneumoniae) and Haemophilus influenzae (H influenzae) to nasopharyngeal cells in vitro. This is an update of a review first published in 2011. To assess the efficacy and safety of xylitol to prevent AOM in children aged up to 12 years. We searched CENTRAL (to Issue 12, 2015), MEDLINE (1950 to January 2016), Embase (1974 to January 2016), CINAHL (1981 to January 2016), LILACS (1982 to January 2016), Web of Science (2011 to January 2016) and International Pharmaceutical Abstracts (2000 to January 2016). Randomised controlled trials (RCTs) or quasi-RCTs of children aged 12 years or younger where xylitol supplementation was compared with placebo or no treatment to prevent AOM. Two review authors independently selected trials from search results, assessed and rated study quality and extracted relevant data for inclusion in the review. We contacted trial authors to request missing data. We noted data on any adverse events of xylitol. We extracted data on relevant outcomes and estimated the effect size by calculating risk ratio (RR), risk difference (RD) and associated 95% confidence intervals (CI). We identified five clinical trials that involved 3405 children for inclusion. For this 2016 update, we identified one new trial for inclusion. This trial was systematically reviewed but due to several sources of heterogeneity, was not included in the meta-analysis. The remaining four trials were of adequate methodological quality. In three RCTs that involved a total of 1826 healthy Finnish children attending daycare, there is moderate quality evidence that xylitol (in any form) can reduce the risk of AOM from 30% to around 22% compared with the control group (RR 0.75, 95% CI 0.65 to 0.88). Among the reasons for dropouts, there were no significant differences in abdominal discomfort and rash between the xylitol and the control groups. Xylitol was not effective in reducing AOM among healthy children during a respiratory infection (RR 1.13, 95% CI 0.83 to 1.53; moderate quality evidence) or among otitis-prone healthy children (RR 0.90, 95% CI 0.67 to 1.21; low-quality evidence). There is moderate quality evidence showing that the prophylactic administration of xylitol among healthy children attending daycare centres can reduce the occurrence of AOM. There is inconclusive evidence with regard to the efficacy of xylitol in preventing AOM among children with respiratory infection, or among otitis-prone children. The meta-analysis was limited because data came from a small number of studies, and most were from the same research group.

[Efficacy and tolerance of a new formulation of amoxicillin 100 mg--clavulanic acid 12.5 mg in acute otitis in infants].

PubMed

Astruc, J

1992-02-01

A multicenter study of the new pediatric formulation of Augmentin (containing 100 mg amoxicillin and 12.5 mg clavulanic acid per ml) in acute otitis media (AOM) in patients aged three months to three years was carried out by hospital-based pediatricians. Study patients seen at the hospital outpatient clinics were given the drug in a daily dosage of 80 mg in three (83% of cases) or four (15%) divided doses for 6 to 10 days; 28% of patients were also given an antiinflammatory agent. A total of 83 patients with a mean age of 13.5 months were included (89% of patients were less than two years of age); one-third of these patients were included after failure of another antimicrobial agent (macrolide 46%, cephalosporin 23%). The AOM was bilateral in most patients (69.5%) and 46% of patients had a history of previous AOM. Temperature was elevated in 85% of cases and more than half the patients had gastrointestinal symptoms (vomiting, diarrhea) prior to initiation of the study drug. At the interim evaluation on the fourth treatment day, tympanic membranes were normal in 43.5% of cases and improved in 22% of cases. Over 92% of patients achieved resolution of their AOM by the end of the treatment period, regardless of whether or not myringostomy had been performed on Do. Among the 27 patients given the study drug as rescue therapy after failure of another antimicrobial, 24 (89%) recovered fully.(ABSTRACT TRUNCATED AT 250 WORDS)

High-Dose Azithromycin versus High-Dose Amoxicillin-Clavulanate for Treatment of Children with Recurrent or Persistent Acute Otitis Media

PubMed Central

Arrieta, Antonio; Arguedas, Adriano; Fernandez, Pilar; Block, Stan L.; Emperanza, Paz; Vargas, Sergio L.; Erhardt, William A.; de Caprariis, Pascal J.; Rothermel, Constance D.

2003-01-01

Infants and young children, especially those in day care, are at risk for recurrent or persistent acute otitis media (AOM). There are no data on oral alternatives to high-dose amoxicillin-clavulanate for treating AOM in these high-risk patients. In this double-blind, double-dummy multicenter clinical trial, we compared a novel, high-dose azithromycin regimen with high-dose amoxicillin-clavulanate for treatment of children with recurrent or persistent AOM. Three hundred four children were randomized; 300 received either high-dose azithromycin (20 mg/kg of body weight once a day for 3 days) or high-dose amoxicillin-clavulanate (90 mg/kg divided twice a day for 10 days). Tympanocentesis was performed at baseline; clinical response was assessed at day 12 to 16 and day 28 to 32. Two-thirds of patients were aged ≤2 years. A history of recurrent, persistent, or recurrent plus persistent AOM was noted in 67, 18, and 14% of patients, respectively. Pathogens were isolated from 163 of 296 intent-to-treat patients (55%). At day 12 to 16, clinical success rates for azithromycin and amoxicillin-clavulanate were comparable for all patients (86 versus 84%, respectively) and for children aged ≤2 years (85 versus 79%, respectively). At day 28 to 32, clinical success rates for azithromycin were superior to those for amoxicillin-clavulanate for all patients (72 versus 61%, respectively; P = 0.047) and for those aged ≤2 years (68 versus 51%, respectively; P = 0.017). Per-pathogen clinical efficacy against Streptococcus pneumoniae and Haemophilus influenzae was comparable between the two regimens. The rates of treatment-related adverse events for azithromycin and amoxicillin-clavulanate were 32 and 42%, respectively (P = 0.095). Corresponding compliance rates were 99 and 93%, respectively (P = 0.018). These data demonstrate the efficacy and safety of high-dose azithromycin for treating recurrent or persistent AOM. PMID:14506028

Clinical role of Cefixime in community-acquired infections.

PubMed

Dreshaj, Sh; Doda-Ejupi, T; Tolaj, I Q; Mustafa, A; Kabashi, S; Shala, N; Geca, Nj; Aliu, A; Daka, A; Basha, N

2011-01-01

Cefixime is an oral third generation cephalosporin, frequently used in respiratory tract infections (RTI) in the pediatric population. However, in some publications cefixime has demonstrated poor efficacy against staphylococci and streptococci. of this study was to evaluate the efficacy of cefixime in the treatment of community-acquired infections in a country where parenteral third generation cephalosporins have been used for a long time. The present study was designed to assess the clinical efficacy, bacteriological eradication rates and tolerability of cefixime in children with community-acquired upper RTI (URTI), lower RTI (LRTI) and uncomplicated urinary tract infections (UTI). The study was prospective, open, and included 89 patients, from 6 months to 28 years, of both sexes, with the diagnosis of community-acquired URTI, LRTI and UTI. The treatment with cefixime was successful in 30/30 (100%) patients suffering from acute otitis media (AOM), in 10/12 (83.3%) with acute sinusitis, in 12/12 patients (100%) with pneumonia, in 31/35 (88.57) with uncomplicated UTI. The antibiotic was well tolerated. In 10 days treatment we recorded one case (1.3%) with acute gastroenteritis and two cases (2.6%) of maculopapular rash. Side-effects were transient and disappeared after finishing therapy in all three of the cases. Community-acquired infections, such as AOM, LRTI and UTI, caused by susceptible pathogens, can be treated with cefixime, as a good choice for a successful clinical response.

Point: From animal models to prevention of colon cancer. Systematic review of chemoprevention in min mice and choice of the model system.

PubMed

Corpet, Denis E; Pierre, Fabrice

2003-05-01

The Apc(Min/+) mouse model and the azoxymethane (AOM) rat model are the main animal models used to study the effect of dietary agents on colorectal cancer. We reviewed recently the potency of chemopreventive agents in the AOM rat model (D. E. Corpet and S. Tache, Nutr. Cancer, 43: 1-21, 2002). Here we add the results of a systematic review of the effect of dietary and chemopreventive agents on the tumor yield in Min mice. The review is based on the results of 179 studies from 71 articles and is displayed also on the internet http://corpet.net/min.(2) We compared the efficacy of agents in the Min mouse model and the AOM rat model, and found that they were correlated (r = 0.66; P < 0.001), although some agents that afford strong protection in the AOM rat and the Min mouse small bowel increase the tumor yield in the large bowel of mutant mice. The agents included piroxicam, sulindac, celecoxib, difluoromethylornithine, and polyethylene glycol. The reason for this discrepancy is not known. We also compare the results of rodent studies with those of clinical intervention studies of polyp recurrence. We found that the effect of most of the agents tested was consistent across the animal and clinical models. Our point is thus: rodent models can provide guidance in the selection of prevention approaches to human colon cancer, in particular they suggest that polyethylene glycol, hesperidin, protease inhibitor, sphingomyelin, physical exercise, epidermal growth factor receptor kinase inhibitor, (+)-catechin, resveratrol, fish oil, curcumin, caffeate, and thiosulfonate are likely important preventive agents.

Pneumococcal Conjugate Vaccines and Otitis Media: An Appraisal of the Clinical Trials

PubMed Central

Fletcher, Mark A.; Fritzell, Bernard

2012-01-01

Streptococcus pneumoniae is the predominant otitis media pathogen and its prevention through effective vaccination could diminish childhood illness and antibiotic use. This paper reviews 5 pneumococcal conjugate vaccine (PCV) trials that used otitis media as an endpoint: Northern California Kaiser Permanente (NCKP; vaccine, 7-valent PCV [PCV7]-CRM); Finnish Otitis Media (FinOM; vaccines, PCV7-CRM or PCV7-OMPC); Native American Trial (vaccine, PCV7-CRM); Pneumococcal Otitis Efficacy Trial (POET; vaccine, 11-valent PCV [PCV11]-PD). For the microbiological endpoint, vaccine efficacy against vaccine-serotype pneumococcal otitis media was about 60% across trials. Against the clinical endpoint of all episodes, vaccine efficacy was 7% (PCV7-CRM/NCKP), 6% (PCV7-CRM/FinOM), −1% (PCV7-OMPC/FinOM), and −0.4% (PCV7-CRM/Native American Trial); 34% against first episodes of ear, nose, and throat specialist-referral cases (PCV11-PD/POET). Both follow-up through 2 years of age, for the 5 trials, and long-term follow-up, for PCV7-CRM/NCKP and PCV7-CRM/FinOM, demonstrated greater vaccine efficacy against recurrent AOM and tympanostomy-tube placement, suggesting that vaccination against early episodes of AOM may prevent subsequent episodes of complicated otitis media. Although study designs varied by primary endpoint measured, age at follow-up, source of middle-ear fluid for culture, case ascertainment, and type of randomization, each clinical trial demonstrated vaccine efficacy against microbiological and/or clinical otitis media. PMID:22701486

Reduced-Concentration Clavulanate for Young Children with Acute Otitis Media.

PubMed

Hoberman, Alejandro; Paradise, Jack L; Rockette, Howard E; Jeong, Jong-Hyeon; Kearney, Diana H; Bhatnagar, Sonika; Shope, Timothy R; Muñiz, Gysella; Martin, Judith M; Kurs-Lasky, Marcia; Haralam, MaryAnn; Pope, Marcia A; Nagg, Jennifer P; Zhao, Wenchen; Miah, Mohammad Kowser; Beumer, Jan; Venkataramanan, Raman; Shaikh, Nader

2017-07-01

Amoxicillin-clavulanate (A/C) is currently the most effective oral antimicrobial in treating children with acute otitis media (AOM), but the standard dosage of 90 mg amoxicillin/6.4 mg clavulanate/kg of body weight/day commonly causes diarrhea. We examined whether an A/C formulation containing lower concentrations of clavulanate would result in less diarrhea while maintaining plasma levels of amoxicillin and clavulanate adequate to eradicate middle-ear pathogens and to achieve clinical success. We conducted an open-label study in children with AOM who were 6 to 23 months of age. In phase 1, we treated 40 children with a reduced-clavulanate A/C formulation providing 90 mg amoxicillin/3.2 mg clavulanate/kg/day for 10 days. In phase 2, we treated 72 children with the same formulation at a dosage of 80 mg amoxicillin/2.85 mg clavulanate/kg/day for 10 days. We compared the rates of protocol-defined diarrhea (PDD), diaper dermatitis, and AOM clinical response in these children with rates we had reported in children who received the standard A/C regimen, and we obtained plasma levels of amoxicillin and clavulanate at various time points. Outcomes in phase 1 children and in children who had received the standard regimen did not differ significantly. Rates of PDD in children receiving phase 2 and standard regimens were 17% and 26%, respectively ( P = 0.10). The corresponding rates of diaper dermatitis were 21% and 33% ( P = 0.04) and of AOM treatment failure were 12% and 16% ( P = 0.44). Symptomatic responses did not differ significantly between regimens; both gave clavulanate levels sufficient to inhibit β-lactamase activity. In young children with AOM, clavulanate dosages lower than those currently used may be associated with fewer side effects without reducing clinical efficacy. (This study has been registered at ClinicalTrials.gov under registration no. NCT02630992.). Copyright © 2017 American Society for Microbiology.

Reduced-Concentration Clavulanate for Young Children with Acute Otitis Media

PubMed Central

Paradise, Jack L.; Rockette, Howard E.; Jeong, Jong-Hyeon; Kearney, Diana H.; Bhatnagar, Sonika; Shope, Timothy R.; Muñiz, Gysella; Martin, Judith M.; Kurs-Lasky, Marcia; Haralam, MaryAnn; Pope, Marcia A.; Nagg, Jennifer P.; Zhao, Wenchen; Miah, Mohammad Kowser; Beumer, Jan; Venkataramanan, Raman; Shaikh, Nader

2017-01-01

ABSTRACT Amoxicillin-clavulanate (A/C) is currently the most effective oral antimicrobial in treating children with acute otitis media (AOM), but the standard dosage of 90 mg amoxicillin/6.4 mg clavulanate/kg of body weight/day commonly causes diarrhea. We examined whether an A/C formulation containing lower concentrations of clavulanate would result in less diarrhea while maintaining plasma levels of amoxicillin and clavulanate adequate to eradicate middle-ear pathogens and to achieve clinical success. We conducted an open-label study in children with AOM who were 6 to 23 months of age. In phase 1, we treated 40 children with a reduced-clavulanate A/C formulation providing 90 mg amoxicillin/3.2 mg clavulanate/kg/day for 10 days. In phase 2, we treated 72 children with the same formulation at a dosage of 80 mg amoxicillin/2.85 mg clavulanate/kg/day for 10 days. We compared the rates of protocol-defined diarrhea (PDD), diaper dermatitis, and AOM clinical response in these children with rates we had reported in children who received the standard A/C regimen, and we obtained plasma levels of amoxicillin and clavulanate at various time points. Outcomes in phase 1 children and in children who had received the standard regimen did not differ significantly. Rates of PDD in children receiving phase 2 and standard regimens were 17% and 26%, respectively (P = 0.10). The corresponding rates of diaper dermatitis were 21% and 33% (P = 0.04) and of AOM treatment failure were 12% and 16% (P = 0.44). Symptomatic responses did not differ significantly between regimens; both gave clavulanate levels sufficient to inhibit β-lactamase activity. In young children with AOM, clavulanate dosages lower than those currently used may be associated with fewer side effects without reducing clinical efficacy. (This study has been registered at ClinicalTrials.gov under registration no. NCT02630992.) PMID:28438923

Comparison of cefuroxime axetil, cefaclor, and amoxicillin-clavulanate potassium suspensions in acute otitis media in infants and children.

PubMed

Pichichero, M; Aronovitz, G H; Gooch, W M; McLinn, S E; Maddern, B; Johnson, C; Darden, P M

1990-10-01

In this randomized, blinded, multicenter comparison study, 377 infants and children with acute otitis media (AOM) received a 10-day course of an oral suspension of one of the following: cefuroxime axetil (CAE), 30 mg/kg/day; cefaclor (CEC), 40 mg/kg/day; or amoxicillin-clavulanate potassium (AMX-CL), 40 mg/kg/day. Clinical efficacy was determined by pneumatic otoscopy and tympanometric testing 3 to 5, 11 to 14, and 22 to 26 days after the initiation of therapy. There was a statistically significant difference among the three treatment groups with respect to clinical outcome; more patients in the CAE group (62%) than in the CEC group (46%) or the AMX-CL group (52%) had complete resolution of signs and symptoms of AOM (including effusion). Paired comparisons revealed a significant difference in efficacy between CAE and CEC and a nearly significant difference between AMX-CL and CEC. Taste acceptability was highest for CEC and lowest for this formulation of CAE. Significantly more patients in the AMX-CL group than in the CAE or CEC group had a side effect, primarily diarrhea, vomiting, or diaper rash. We conclude that CAE suspension has greater clinical efficacy than CEC and fewer side effects than AMX-CL.

Efficacy of pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) in young Latin American children: A double-blind randomized controlled trial.

PubMed

Tregnaghi, Miguel W; Sáez-Llorens, Xavier; López, Pio; Abate, Hector; Smith, Enrique; Pósleman, Adriana; Calvo, Arlene; Wong, Digna; Cortes-Barbosa, Carlos; Ceballos, Ana; Tregnaghi, Marcelo; Sierra, Alexandra; Rodriguez, Mirna; Troitiño, Marisol; Carabajal, Carlos; Falaschi, Andrea; Leandro, Ana; Castrejón, Maria Mercedes; Lepetic, Alejandro; Lommel, Patricia; Hausdorff, William P; Borys, Dorota; Ruiz Guiñazú, Javier; Ortega-Barría, Eduardo; Yarzábal, Juan P; Schuerman, Lode

2014-06-01

The relationship between pneumococcal conjugate vaccine-induced antibody responses and protection against community-acquired pneumonia (CAP) and acute otitis media (AOM) is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) on these end points. The primary objective was to demonstrate vaccine efficacy (VE) in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ≥ 40 µg/ml); other protocol-specified outcomes were also assessed. This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster) at 2, 4, 6, and 15-18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ≥2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n = 10,295; control, n = 10,201), per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p = 0.002) against B-CAP (conclusive for primary objective) and 25.7% (95% CI: 8.4%, 39.6%) against World Health Organization-defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1%) against B-CAP and 23.4% (95% CI: 8.8%, 35.7%) against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28-30 mo for CAP and invasive pneumococcal disease (IPD) (PHiD-CV, n = 10,211; control, n = 10,140) and AOM (n = 3,010 and 2,979, respectively). Per-protocol VE was 16.1% (95% CI: -1.1%, 30.4%; one-sided p = 0.032) against clinically confirmed AOM, 67.1% (95% CI: 17.0%, 86.9%) against vaccine serotype clinically confirmed AOM, 100% (95% CI: 74.3%, 100%) against vaccine serotype IPD, and 65.0% (95% CI: 11.1%, 86.2%) against any IPD. Results were consistent between intent-to-treat and per-protocol analyses. Serious adverse events were reported for 21.5% (95% CI: 20.7%, 22.2%) and 22.6% (95% CI: 21.9%, 23.4%) of PHiD-CV and control recipients, respectively. There were 19 deaths (n = 11,798; 0.16%) in the PHiD-CV group and 26 deaths (n = 11,799; 0.22%) in the control group. A significant study limitation was the lower than expected number of captured AOM cases. Efficacy was demonstrated against a broad range of pneumococcal diseases commonly encountered in young children in clinical practice. www.ClinicalTrials.gov NCT00466947.

Relationship with original pathogen in recurrence of acute otitis media after completion of amoxicillin/clavulanate: bacterial relapse or new pathogen.

PubMed

Kaur, Ravinder; Casey, Janet R; Pichichero, Michael E

2013-11-01

We sought to determine whether recurrent acute otitis media (rAOM) occurring within 30 days of amoxicillin/clavulanate treatment was caused by bacterial relapse or new pathogens. Pneumococcal conjugate vaccinated children, age 6-36 months, enrolled in a prospective, longitudinal study experiencing rAOM<1 month after completing amoxicillin/clavulanate therapy were studied. AOM episodes occurred between June 2006 and November 2012. Multilocus sequence typing was used to genotype isolates. Sixty-six children were in the study cohort; 63 otopathogens were recovered from middle ear fluid after tympanocentesis. Nontypeable Haemophilus influenzae (NTHi) accounted for 47% of initial AOMs versus 15% by Streptococcus pneumoniae (Spn), P<0.0001. NTHi accounted for 42% of rAOM versus 24% by Spn (P value=0.04). NTHi was the main otopathogen that caused true bacteriologic relapses (77%). β-lactamase-producing NTHi and penicillin nonsusceptible Spn were not more common in rAOM than initial AOM infections. Among 21 paired (initial and rAOM events) NTHi isolates genotyped, 13 (61.9%) were the same organism; 1 of 9 (11.1%) of paired Spn isolates was the same (P value=0.017). rAOM occurring within a week of stopping amoxicillin/clavulanate was a different pathogen in 21% of cases, 8-14 days later in 33%, 15-21 days in 41% and 22-30 days in 57% (P=0.04). In amoxicillin/clavulanate-treated children, NTHi was the main otopathogen that caused true bacteriologic relapses. New pathogens causing rAOM versus persistence of the initial pathogen significantly increased week to week. Neither relapses nor new infections were caused more frequently by β-lactamase producing NTHi or penicillin nonsusceptible Spn.

Amelioration of azoxymethane induced-carcinogenesis by reducing oxidative stress in rat colon by natural extracts

PubMed Central

2014-01-01

Background Azoxymethane (AOM) is a potent carcinogenic agent commonly used to induce colon cancer in rats; the cytotoxicity of AOM is considered to mediate oxidative stress. This study investigated the chemopreventive effect of three natural extracts [pomegranate peel extract (PomPE), papaya peel extract (PapPE) and seaweed extract (SE)] against AOM-induced oxidative stress and carcinogenesis in rat colon. Methods Eighty Sprague–Dawley rats (aged 4 weeks) were randomly divided into 8 groups (10 rats/group). Control group was fed a basal diet; AOM-treated group was fed a basal diet and received AOM intraperitonial injections for two weeks at a dose of 15 mg/kg bodyweight, whereas the other six groups were received oral supplementation of PomPE, PapPE or SE, in the presence or absence of AOM injection. All animals were continuously fed ad-libitum until aged 16 weeks, then all rats were sacrificed and the colon tissues were examined microscopically for pathological changes and aberrant crypt foci (ACF) development, genotoxicity (induced micronuclei (MN) cells enumeration), and glutathione and lipid peroxidation. Results Our results showed that AOM-induced ACF development and pathological changes in the colonic mucosal tissues, increased bone marrow MN cells and oxidative stress (glutathione depletion, lipid peroxidation) in rat colonic cells. The concomitant treatment of AOM with PomPE, PapPE or SE significantly ameliorated the cytotoxic effects of AOM. Conclusions The results of this study provide in-vivo evidence that PomPE, PapPE and SE reduced the AOM-induced colon cancer in rats, through their potent anti-oxidant activities. PMID:24533833

Cost-effectiveness Analysis of Aripiprazole Once-Monthly for the Treatment of Schizophrenia in the UK.

PubMed

Tempest, Michael; Sapin, Christophe; Beillat, Maud; Robinson, Paul; Treur, Maarten

2015-12-01

Schizophrenia is a severe and debilitating psychiatric disorder. Pharmacological interventions aim to ameliorate symptoms and reduce the risk of relapse and costly hospitalisation. Despite the established efficacy of antipsychotic medication, compliance to treatment is poor, particularly with oral formulation. The emergence of long acting injectable (LAI) antipsychotic formulations in recent years has aimed to counteract the poor compliance rates observed and optimise long term patient outcomes. To estimate the cost-effectiveness of aripiprazole once-monthly 400mg (AOM 400) vs. risperidone long acting injectable (RLAI), paliperidone long acting injectable (PLAI) and olanzapine long acting injectable (OLAI) in the maintenance treatment of chronic, stable schizophrenia patients in the United Kingdom. A Markov model was developed to emulate the treatment pathway of a hypothetical cohort of patients initiating maintenance treatment with LAI antipsychotics. The economic analysis was conducted from a National Health Service (NHS) and Personal Social Services (PSS) perspective over a 10 year time horizon. Efficacy and safety probabilities were derived from mixed treatment comparisons (MTCs) where possible. Analyses were conducted assuming pooled dosing from randomised clinical trials included in the MTCs. The model estimates that AOM 400 improves clinical outcomes by reducing relapses per patient comparative to other LAIs over the model time horizon (2.38, 2.53, 2.70, and 2.67 for AOM 400, RLAI, PLAI and OLAI respectively). In the deterministic analysis, AOM 400 dominated PLAI and OLAI; an incremental cost-effectiveness ratio (ICER) of GBP 3,686 per QALY gained was observed against RLAI. Results from the univariate sensitivity analyses highlighted the probability and cost of relapse as main drivers for cost-effectiveness. In the probabilistic sensitivity analysis, AOM 400 demonstrated a marginally higher probability of being cost-effective (51%) than RLAI, PLAI and OLAI (48%, 1% and 0%, respectively) at a willingness to pay threshold of GBP 20,000. The model was built to accommodate results of an adjusted MTC analysis. Furthermore the model effectively captures repercussions of deteriorating compliance to treatment by incorporating three levels of compliance with elevated risks of relapse for partial compliance and non-compliance. Limitations of the analysis include the limited number of studies incorporated in the MTC, the extrapolation of short term clinical data and the exclusion of the wider societal burden. Comparative to other atypical antipsychotics, AOM 400 represents value for money in the maintenance treatment of chronic, stable schizophrenia; however, in light of the PSA findings and comparable cost-effectiveness (i.e. against RLAI), the product profile and wider benefits of the respective treatments must be taken into account when prescribing antipsychotics. Future research should assess the use of LAI antipsychotics earlier in the disease course of schizophrenia to see whether improved compliance and outcomes shortly following the onset of psychosis has the potential to alter the disease trajectory. Moreover it should be assessed whether changes in the disease trajectory can alleviate cost and resource pressures placed on national health services.

Current face of acute otitis media: microbiology and prevalence resulting from widespread use of heptavalent pneumococcal conjugate vaccine.

PubMed

Brunton, Stephen

2006-01-01

Many causes can be proposed for a change in the microbiologic makeup of a specific disease state. However, when viewed through the scope of recent events, only one is likely to be the true cause of a change in the microbiology of acute otitis media (AOM): the release and widespread use of heptavalent pneumococcal conjugate vaccine (PCV-7). The aim of this report was to review the microbiology and prevalence of AOM before and after the release and widespread use of PCV-7. For this brief review, we used a MEDLINE search to identify English-language literature related to the microbiology of AOM before and after the release of PCV-7 in 2000 in the United States (key terms: acute otitis media, AOM, Haemophilus influenzae, H influenzae, Streptococcus pneumoniae, and S pneumoniae; years: 1980-2005). Studies using tympanocentesis to identify the pathogen in recurrent or persistent AOM were examined; US studies reporting AOM microbiology before and after the release of PCV-7 in the same population were considered for the post-PCV-7 analysis. Following the release of PCV-7, a decrease in the overall rates of AOM was noted. This decrease brings into question the resultant effect on the microbiology of AOM. Our literature search revealed 2 studies that examined the microbiology of AOM before and after the release of PCV-7 in the United States. These 2 studies, conducted in dispersed geographic regions (rural Kentucky and Rochester, New York), illustrated a change in the predominant causative pathogen in AOM, from S pneumoniae to H influenzae in the population of children 7 to 24 months of age with recurrent AOM. Given the time period of the change, these shifts could be related to the release and widespread use of PCV-7. Since the 1990s, the predominant causative pathogen in recurrent AOM changed from S pneumoniae to H influenzae, possibly as a result of the release and widespread use of PCV 7. Although PCV-7 use was slowed from August 2001 to May 2003 and again from February to September 2004 by nationwide shortages, those shortages have now been resolved, and compliance with the full vaccine schedule is expected to increase.

Cellular Immune Response in Young Children Accounts for Recurrent Acute Otitis Media

PubMed Central

Sharma, Sharad K.; Pichichero, Michael E.

2013-01-01

Acute otitis media (AOM) is a common disease in young children. Streptococcus pneumoniae(Spn) and Haemophilus influenzae (NTHi) are the two most common pathogens that cause AOM. Over the past 5 years our group has been studying the immunologic profile of children that experience repeated AOM infections despite tympanocentesis drainage of middle ear fluid and individualized antibiotic treatment; we call these children stringently-defined otitis-prone (sOP). Although protection against AOM is primarily mediated by ototpathogen-specific antibody, our recent studies suggest that suboptimal memory B-& T- cell responses and an immaturity in antigen presenting cells may play a significant role in the propensity to recurrent AOM infections. This review focuses on the studies performed to define immunologic dysfunction in sOP children. PMID:24022464

Efficacy of Pneumococcal Nontypable Haemophilus influenzae Protein D Conjugate Vaccine (PHiD-CV) in Young Latin American Children: A Double-Blind Randomized Controlled Trial

PubMed Central

Tregnaghi, Miguel W.; Sáez-Llorens, Xavier; López, Pio; Abate, Hector; Smith, Enrique; Pósleman, Adriana; Calvo, Arlene; Wong, Digna; Cortes-Barbosa, Carlos; Ceballos, Ana; Tregnaghi, Marcelo; Sierra, Alexandra; Rodriguez, Mirna; Troitiño, Marisol; Carabajal, Carlos; Falaschi, Andrea; Leandro, Ana; Castrejón, Maria Mercedes; Lepetic, Alejandro; Lommel, Patricia; Hausdorff, William P.; Borys, Dorota; Guiñazú, Javier Ruiz; Ortega-Barría, Eduardo; Yarzábal, Juan P.; Schuerman, Lode

2014-01-01

Background The relationship between pneumococcal conjugate vaccine–induced antibody responses and protection against community-acquired pneumonia (CAP) and acute otitis media (AOM) is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) on these end points. The primary objective was to demonstrate vaccine efficacy (VE) in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ≥ 40 µg/ml); other protocol-specified outcomes were also assessed. Methods and Findings This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster) at 2, 4, 6, and 15–18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ≥2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n = 10,295; control, n = 10,201), per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p = 0.002) against B-CAP (conclusive for primary objective) and 25.7% (95% CI: 8.4%, 39.6%) against World Health Organization–defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1%) against B-CAP and 23.4% (95% CI: 8.8%, 35.7%) against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28–30 mo for CAP and invasive pneumococcal disease (IPD) (PHiD-CV, n = 10,211; control, n = 10,140) and AOM (n = 3,010 and 2,979, respectively). Per-protocol VE was 16.1% (95% CI: −1.1%, 30.4%; one-sided p = 0.032) against clinically confirmed AOM, 67.1% (95% CI: 17.0%, 86.9%) against vaccine serotype clinically confirmed AOM, 100% (95% CI: 74.3%, 100%) against vaccine serotype IPD, and 65.0% (95% CI: 11.1%, 86.2%) against any IPD. Results were consistent between intent-to-treat and per-protocol analyses. Serious adverse events were reported for 21.5% (95% CI: 20.7%, 22.2%) and 22.6% (95% CI: 21.9%, 23.4%) of PHiD-CV and control recipients, respectively. There were 19 deaths (n = 11,798; 0.16%) in the PHiD-CV group and 26 deaths (n = 11,799; 0.22%) in the control group. A significant study limitation was the lower than expected number of captured AOM cases. Conclusions Efficacy was demonstrated against a broad range of pneumococcal diseases commonly encountered in young children in clinical practice. Trial registration www.ClinicalTrials.gov NCT00466947 Please see later in the article for the Editors' Summary PMID:24892763

Pediatric Acute Otitis Media in the Era of Pneumococcal Vaccination.

PubMed

Tawfik, Kareem O; Ishman, Stacey L; Altaye, Mekibib; Meinzen-Derr, Jareen; Choo, Daniel I

2017-05-01

Objectives (1) Describe longitudinal trends in annual prevalence of hospital admission for pediatric acute otitis media (AOM) and complications of AOM (CAOM) since introduction of pneumococcal vaccination in 2000 and (2) describe the longitudinal trend of prevalence of hospital admission for pneumococcal meningitis in children with AOM-related diagnoses in the postvaccination era. Study Design Retrospective analysis of Kids' Inpatient Database from 2000 to 2012. Setting Community, nonrehabilitation hospitals. Subjects and Methods To determine annual prevalence of admission for AOM/CAOM, nationally weighted frequencies of children aged <21 years with acute suppurative otitis media, acute mastoiditis, suppurative labyrinthitis, and/or acute petrositis were collected. The frequency of coexisting pneumococcal meningitis diagnoses among these patients was also collected. Trend analysis of prevalences of admission for AOM/CAOM and for pneumococcal meningitis occurring in the setting of AOM/CAOM from 2000 to 2012 was performed. Results Between 2000 and 2012, annual prevalence of admission for AOM/CAOM decreased from 3.956 to 2.618 per 100,000 persons ( P < .0001) (relative risk reduction 34%). Declines in admission prevalence were most pronounced in children <1 year of age (from 22.647 to 8.715 per 100,000 persons between 2000 and 2012, P < .0001) and 1 to 2 years of age (from 13.652 to 5.554 per 100,000 persons between 2000 and 2012, P < .0001). For all ages, the admission prevalence for pneumococcal meningitis and concomitant AOM/CAOM decreased (from 1.760 to 0.717 per 1,000,000 persons, P < .0001) over the study period. Conclusions The prevalence of hospital admission for pediatric AOM/CAOM has declined since the advent of pneumococcal vaccination. Admission rates for pneumococcal meningitis with AOM/CAOM have similarly declined.

Impact of electron acceptor availability on the anaerobic oxidation of methane in coastal freshwater and brackish wetland sediments

NASA Astrophysics Data System (ADS)

Segarra, Katherine E. A.; Comerford, Christopher; Slaughter, Julia; Joye, Samantha B.

2013-08-01

Methane, a powerful greenhouse gas, is both produced and consumed in anoxic coastal sediments via microbial processes. Although the anaerobic oxidation of methane (AOM) is almost certainly an important process in coastal freshwater and salt marsh sediments, the factors that control the rates and pathways of AOM in these habitats are poorly understood. Here, we present the first direct measurements of AOM activity in freshwater (0 PSU) and brackish (25 PSU) wetland sediments. Despite disparate sulfate concentrations, both environments supported substantial rates of AOM. Higher sulfate reduction (SR) rates were measured in the freshwater site and SR at both sites was of sufficient magnitude to support the observed AOM activity. Laboratory incubations of freshwater and brackish tidal, wetland sediments amended with either nothing [control], sulfate, nitrate, manganese oxide (birnessite) or iron oxide (ferrihydrite) and supplied with a methane headspace were used to evaluate the impact(s) of electron acceptor availability on potential AOM rates. Maximum AOM rates in brackish slurries occurred in the sulfate amendments. In contrast, addition of sulfate and several possible electron acceptors to the freshwater slurries decreased AOM rates relative to the control. High ratios of AOM activity relative to SR activity in the nitrate, birnessite, and ferrihydrite treatments of both the brackish and freshwater slurries provided evidence of AOM decoupled from SR. This study demonstrates that both freshwater and brackish coastal wetland sediments support considerable rates of anaerobic methanotrophy and provides evidence for sulfate-independent AOM that may be coupled to nitrate, iron, or manganese reduction in both environments.

Acute otitis media and sociomedical risk factors among unselected children in Greenland.

PubMed

Homøe, P; Christensen, R B; Bretlau, P

1999-06-15

To describe the sociomedical risk factors associated with episodes of acute otitis media (AOM), recurrent AOM (rAOM), and chronic otitis media (COM) in Greenlandic children and especially to point out children at high risk of rAOM (defined as > 5 AOM episodes since birth) and COM which are prevalent among Inuit children all over the Arctic. The study design was cross-sectional and included 740 unselected children, 3, 4, 5, and 8-years-old, living in two major Greenlandic towns, Nuuk and Sisimiut. All children were otologically examined and the parents answered a questionnaire containing sociomedical variables including ethnicity, family history of OM, housing, insulation, crowding, daycare, passive cigarette smoking, breast feeding, type of diet, allergy, and chronic diseases. Historical data were cross-checked in medical records which also formed the basis for the drop-out analyses. Statistical analyses included frequency tests, calculation of odds ratio (OR), and multiple logistic regression. The attendance rate was 86%. Former episode of AOM was reported by 2/3 of the children, rAOM by 20%, and COM by 9%. The following variables were found significantly more often in children with AOM by simple frequency testing: Parental (OR = 1.83), sibling (OR = 1.62), and parental plus sibling (OR = 2.56) history of OM, crowding (OR = 5.55), long period of exclusive breast feeding ( > 4 months) (OR = 2.47), and recent acute disease (P = 0.034). The following variables were found significantly more often in children with rAOM or COM by simple frequency testing: Parental history of OM (OR = 1.60; OR = 2.11, respectively) and no recall of breast feeding (P = 0.005; P = 0.003, respectively). Also, COM was found significantly more often in children with two Greenlandic parents (OR = 3.07). A multiple logistic regression test denoted only parental history of OM (OR = 1.82) and long period of exclusive breast feeding (OR = 1.14) as significant predictors of AOM. Many of the risk factors usually associated with AOM could not be confirmed as risk factors in this survey. Parental history of OM and long period of exclusive breast feeding were the strongest factors associated with AOM in Greenlandic children and ethnicity was associated with COM. However, the study confirms that AOM is a multifactorial disease determined by a number of genetic and environmental factors.

Freshwater wetland sediments support substantial rates of anaerobic oxidation of methane (AOM)

NASA Astrophysics Data System (ADS)

Segarra, K. E.; Samarkin, V.; Schubotz, F.; Yoshinaga, M. Y.; Hinrichs, K.; Joye, S. B.

2012-12-01

Freshwater wetlands are characterized by high rates of methanogenesis and are the single largest source of atmospheric methane. Anaerobic oxidation of methane (AOM), a previously underappreciated process in these systems, may be an important component in freshwater methane budgets. Here we report some of the first direct measurements of AOM in wetland sediments. We examined seasonal methane cycling within three freshwater wetlands (two peat wetlands and one tidal, freshwater creekbank) along the eastern coast of the US. Rates of AOM were high (up to 286 nmol per cubic cm per day) and varied on a seasonal basis. Despite low sulfate concentrations, rates of sulfate reduction were sufficient to support all the observed AOM activity, though rates of these two processes were not correlated. This study highlights the importance of AOM in freshwater sediments, where this process, in conjunction with sulfate reduction, may control emissions of methane to the atmosphere through competitive interactions with methanogens and the consumption of large fractions of the methane produced from acetate and hydrogen. The zone of maximum AOM activity was marked by enriched stable carbon isotopic signatures (δ13C) of methane and depleted signatures of DIC. However, the δ13C of archaeal and bacterial lipids were not indicative of methanotrophy. Studies that evaluate the role of AOM in wetlands using lipid and isotope-based approaches may therefore underestimate its importance.

[Pharmacokinetics and safety of aripiprazole long-acting injection, following multiple deltoid administrations in schizophrenia patients in Japan].

PubMed

Ishigooka, Jun; Noda, Takamasa; Nishiyama, Kosuke; Tamaru, Noriko; Shima, Tomoko; Yamasaki, Yumiko; Tadori, Yoshihiro

2016-06-01

Aripiprazole once-monthly (AOM) was previously approved for treatment of schizophrenia as monthly injections in the gluteal muscle. The deltoid muscle provides a more accessible injection site. The present study was conducted in Japanese schizophrenia patients as a 24-week, open-label trial that assessed the pharmacokinetics and safety of 5 sequential doses of AOM 400 mg (AOM 400) once every 4 weeks administered in the deltoid muscle. Patients treated with an oral atypical antipsychotic (other than aripiprazole) continued to receive their pre-study medication up to 14 days after the first AOM 400 injection. The completion rate was 76.5% (n = 13/17). Mean aripiprazole plasma C(min) almost reached steady-state by the fourth AOM 400 injection. After the fifth AOM 400 injection, mean aripiprazole AUC(28d), C(max) and C(min) were 165 μg x h/ml, 331 ng/ml and 201 ng/ml, respectively, which were similar to previously published pharmacokinetic parameters after the fifth gluteal injection of AOM 400. The most common treatment-emergent adverse event (TEAE) was injection site pain (35.3%). Most TEAEs were classified as mild in intensity. In conclusion, the deltoid injection of AOM can be considered an alternative route of administration, as deltoid and gluteal injections are interchangeable in terms of aripiprazole plasma concentrations, with no additional safety issues.

Diagnostic inaccuracy and subject exclusions render placebo and observational studies of acute otitis media inconclusive.

PubMed

Pichichero, Michael E; Casey, Janet R

2008-11-01

Diagnostic accuracy and appropriate inclusion/exclusion criteria representative of children at greatest risk is of paramount importance in trials to evaluate placebo or observation as an option for acute otitis media (AOM) management. Twelve observational studies spanning the time frame 1958-2005 and 13 natural history studies spanning the time frame 1968-2006 were evaluated for the diagnostic criteria, inclusion criteria, and exclusion criteria applied within the study design. Although a bulging or full tympanic membrane (TM) with effusion is the best indication of a diagnosis of bacterial AOM based on tympanocentesis findings, few observational and natural history studies required a bulging TM. Examination of subject inclusion criteria showed that many subjects did not have AOM but rather had no middle ear disease at all or they had otitis media with effusion. Exclusion criteria of subjects were also remarkable. Frequently children <2 years old were excluded; mean age among the studies reflected an older age group, unlike the true epidemiology of AOM. Otitis prone children, those with severe disease, with a bulging TM, with fever, with a definite need for antibiotics, with recent antibiotic treatment, with recent AOM, or with perforation of the TM were often excluded. Guidelines and some authorities have overlooked or discounted the importance of the issues of inaccurate diagnosis on study entry, broad inclusion criteria, and the creation of bias in exclusion criteria among placebo/natural history trials in AOM. The current data favoring observation of children with AOM should be reconsidered until better studies are conducted.

Anticarcinogenic efficacy of phytic acid extracted from rice bran on azoxymethane-induced colon carcinogenesis in rats.

PubMed

Norazalina, S; Norhaizan, M E; Hairuszah, I; Norashareena, M S

2010-05-01

This study is carried out to determine the potential of phytic acid extracted from rice bran in the suppression of colon carcinogenesis induced by azoxymethane (AOM) in rats. Seventy-two male Sprague-Dawley rats were divided into 6 groups with 12 rats in each group. The intended rats for cancer treatment received two intraperitoneal injections of AOM in saline (15mg/kg bodyweight) over a 2-week period. The treatments of phytic acid were given in two concentrations: 0.2% (w/v) and 0.5% (w/v) during the post-initiation phase of carcinogenesis phase via drinking water. The colons of the animals were analyzed for detection and quantification of aberrant crypt foci (ACF) after 8 weeks of treatment. The finding showed treatment with 0.2% (w/v) extract phytic acid (EPA) gave the greatest reduction in the formation of ACF. In addition, phytic acid significantly suppressed the number of ACF in the distal, middle and proximal colon as compared to AOM alone (p<0.05). For the histological classification of ACF, treatment with 0.5% (w/v) commercial phytic acid (CPA) had the highest percentage (71%) of non-dysplastic ACF followed by treatment with 0.2% (w/v) EPA (61%). Administration of phytic acid also reduced the incidence and multiplicity of total tumors even though there were no significant differences between groups. In conclusion, this study found the potential value of phytic acid extracted from rice bran in reducing colon cancer risk in rats.

Acute otitis media with spontaneous tympanic membrane perforation.

PubMed

Principi, N; Marchisio, P; Rosazza, C; Sciarrabba, C S; Esposito, S

2017-01-01

The principal aim of this review is to present the current knowledge regarding acute otitis media (AOM) with spontaneous tympanic membrane perforation (STMP) and to address the question of whether AOM with STMP is a disease with specific characteristics or a severe case of AOM. PubMed was used to search for all studies published over the past 15 years using the key words "acute otitis media" and "othorrea" or "spontaneous tympanic membrane perforation". More than 250 articles were found, but only those published in English and providing data on aspects related to perforation of infectious origin were considered. Early Streptococcus pneumoniae infection due to invasive pneumococcal strains, in addition to coinfections and biofilm production due mainly to non-typeable Haemophilus influenzae, seem to be precursors of STMP. However, it is unclear why some children have several STMP episodes during the first years of life that resolve without complications in adulthood, whereas other children develop chronic suppurative otitis media. Although specific aetiological agents appear to be associated with an increased risk of AOM with STMP, further studies are needed to determine whether AOM with STMP is a distinct disease with specific aetiological, clinical and prognostic characteristics or a more severe case of AOM than the cases that occur without STMP. Finally, it is important to identify preventive methods that are useful not only in otitis-prone children with uncomplicated AOM, but also in children with recurrent AOM and those who experience several episodes with STMP.

Kinetic study on anaerobic oxidation of methane coupled to denitrification.

PubMed

Yu, Hou; Kashima, Hiroyuki; Regan, John M; Hussain, Abid; Elbeshbishy, Elsayed; Lee, Hyung-Sool

2017-09-01

Monod kinetic parameters provide information required for kinetic analysis of anaerobic oxidation of methane coupled to denitrification (AOM-D). This information is critical for engineering AOM-D processes in wastewater treatment facilities. We first experimentally determined Monod kinetic parameters for an AOM-D enriched culture and obtained the following values: maximum specific growth rate (μ max ) 0.121/d, maximum substrate-utilization rate (q max ) 28.8mmol CH 4 /g cells-d, half maximum-rate substrate concentration (K s ) 83μΜ CH 4 , growth yield (Y) 4.76gcells/mol CH 4 , decay coefficient (b) 0.031/d, and threshold substrate concentration (S min ) 28.8μM CH 4 . Clone library analysis of 16S rRNA and mcrA gene fragments suggested that AOM-D reactions might have occurred via the syntrophic interaction between denitrifying bacteria (e.g., Ignavibacterium, Acidovorax, and Pseudomonas spp.) and hydrogenotrophic methanogens (Methanobacterium spp.), supporting reverse methanogenesis-dependent AOM-D in our culture. High μ max and q max , and low K s for the AOM-D enrichment imply that AOM-D could play a significant role in mitigating atmospheric methane efflux. In addition, these high kinetic features suggest that engineered AOM-D systems may provide a sustainable alternative to nitrogen removal in wastewater treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of algal organic matter released from Microcystis aeruginosa and Chlorella sp. on the fouling of a ceramic microfiltration membrane.

PubMed

Zhang, Xiaolei; Devanadera, Ma Catriona E; Roddick, Felicity A; Fan, Linhua; Dalida, Maria Lourdes P

2016-10-15

Algal blooms lead to the secretion of algal organic matter (AOM) from different algal species into water treatment systems, and there is very limited information regarding the impact of AOM from different species on the fouling of ceramic microfiltration (MF) membranes. The impact of soluble AOM released from Microcystis aeruginosa and Chlorella sp. separately and together in feedwater on the fouling of a tubular ceramic microfiltration membrane (alumina, 0.1 μm) was studied at lab scale. Multi-cycle MF tests operated in constant pressure mode showed that the AOM (3 mg DOC L(-1)) extracted from the cultures of the two algae in early log phase of growth (12 days) resulted in less flux decline compared with the AOM from stationary phase (35 days), due to the latter containing significantly greater amounts of high fouling potential components (protein and humic-like substances). The AOM released from Chlorella sp. at stationary phase led to considerably greater flux decline and irreversible fouling resistance compared with that from M. aeruginosa. The mixture of the AOM (1:1, 3 mg DOC L(-1)) from the two algal species showed more similar flux decline and irreversible fouling resistance to the AOM from M. aeruginosa than Chlorella sp. This was due to the characteristics of the AOM mixture being more similar to those for M. aeruginosa than Chlorella sp. The extent of the flux decline for the AOM mixture after conventional coagulation with aluminium chlorohydrate or alum was reduced by 70%. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quality-of-Life Differences among Diagnostic Subgroups of Children Receiving Ventilating Tubes for Otitis Media.

PubMed

Heidemann, Christian Hamilton; Lauridsen, Henrik Hein; Kjeldsen, Anette Drøhse; Faber, Christian Emil; Johansen, Eva Charlotte Jung; Godballe, Christian

2015-10-01

The pathological picture may differ considerably between diagnostic subgroups of children with otitis media receiving ventilating tubes. The aims of this study are to investigate differences in quality of life among diagnostic subgroups of children treated with ventilating tubes and to investigate possible predictors for clinical success. Longitudinal observational study. Secondary care units. Four hundred ninety-one families were enrolled in the study. The Otitis Media-6 questionnaire was applied in the assessment of child quality of life. Caregivers completed questionnaires at 7 time points from before treatment to 18-month follow-up. Logistic regression analysis was used to investigate possible predictors for clinical success. Response rates ranged from 96% to 81%; diagnostic distribution: 15% recurrent acute otitis media (rAOM), 47% otitis media with effusion (OME), and 38% mixed diagnosis of rAOM and OME (rAOM/OME). There were no significant differences between children diagnosed with rAOM and children diagnosed with rAOM/OME. However, these children had a significantly poorer quality of life at baseline compared with children diagnosed with only OME. Factors associated with clinical success included a diagnosis of rAOM, number of interrupted nights, physician visits, and canceled social activities due to OM. Results highlight the importance of distinguishing between diagnostic subgroups of children having ventilating tube treatment. A diagnosis of rAOM was found to predict baseline quality of life. Children with rAOM with or without OME were found to suffer significantly more than children with only OME before treatment. Factors associated with disease severity were found to predict clinical success. © American Academy of Otolaryngology-Head and Neck Surgery Foundation 2015.

Potentiating NK cell activity by combination of Rosuvastatin and Difluoromethylornithine for effective chemopreventive efficacy against Colon Cancer

PubMed Central

Janakiram, Naveena B.; Mohammed, Altaf; Bryant, Taylor; Zhang, Yuting; Brewer, Misty; Duff, Ashley; Biddick, Laura; Singh, Anil; Lightfoot, Stan; Steele, Vernon E; Rao, Chinthalapally V.

2016-01-01

Colorectal cancer (CRC) is the second highest cause of cancer-related deaths. A successful strategy to improve chemopreventive efficacies is by down-regulating tumor polyamines and enhancing NK cell activities. Colonic carcinogenesis was induced by azoxymethane (AOM) in male F344 rats. Eight weeks after AOM treatment, animals were fed diets containing Rosuvastatin and difluromethylornithine (DFMO) individually and in combination for 40 weeks. Both agents showed significant suppression of adenocarcinoma multiplicity and incidence with no toxicity compared to untreated rats. Low-dose Rosuvastatin plus DFMO suppressed colon adenocarcinoma multiplicity by 76% compared to low-dose Rosuvastatin (29%) and DFMO (46%), suggesting additive efficacy. Furthermore, low-dose combination caused a delay in colonic adenocarcinoma progression. DFMO, Rosuvastatin and/or combinations significantly decreased polyamine content and increased intra-tumoral NK cells expressing perforin plus IFN-γ compared to untreated colon tumors. Further ex-vivo analysis of splenic NK cells exposed to DFMO, Rosuvastatin or combination resulted in an increase of NKs with perforin expression. This is the first report on Rosuvastatin alone or combination strategy using clinically relevant statin plus DFMO doses which shows a significant suppression of colon adenocarcinomas, and their potential in increasing functional NK cells. This strategy has potential for further testing in high risk individuals for colon cancer. PMID:27841323

Constraining the relationships between anaerobic oxidation of methane and sulfate reduction under in situ methane concentrations

NASA Astrophysics Data System (ADS)

Zhuang, G.; Wegener, G.; Joye, S. B.

2017-12-01

The anaerobic oxidation of methane (AOM) is an important microbial metabolism in the global carbon cycle. In marine methane seeps sediment, this process is mediated by syntrophic consortium that includes anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). Stoichiometrically in AOM methane oxidation should be coupled to sulfate reduction (SR) in a 1:1 ratio. However, weak coupling of AOM and SR in seep sediments was frequently observed from the ex situ rate measurements, and the metabolic dynamics of AOM and SR under in situ conditions remain poorly understood. Here we investigated the metabolic activity of AOM and SR with radiotracers by restoring in situ methane concentrations under pressure to constrain the in situ relationships between AOM and SR in the cold seep sediments of Gulf of Mexico as well as the sediment-free AOM enrichments cultivated from cold seep of Italian Island Elba or hydrothermal vent of Guaymas Basin5. Surprisingly, we found that AOM rates strongly exceeded those of SR when high pressures and methane concentrations were applied at seep sites of GC600 and GC767 in Gulf of Mexico. With the addition of molybdate, SR was inhibited but AOM was not affected, suggesting the potential coupling of AOM with other terminal processes. Amendments of nitrate, iron, manganese and AQDS to the SR-inhibited slurries did not stimulate or inhibit the AOM activity, indicating either those electron acceptors were not limiting for AOM in the sediments or AOM was coupled to other process (e.g., organic matter). In the ANME enrichments, higher AOM rates were also observed with the addition of high concentrations of methane (10mM and 50 mM). The tracer transfer of CO2 to methane, i.e., the back reaction of AOM, increased with increasing methane concentrations and accounted for 1%-5% of the AOM rates. AOM rates at 10 mM and 50 mM methane concentration were much higher than the SR rates, suggesting those two processes were not tightly coupled. Collectively, our results provided evidence for the possible decoupling of AOM and SR under in situconditions. This decoupling appears to be widespread in methane-rich marine sediment, motivating a wide variety of future research endeavors.

Osteoporosis medication dispensing for older Australian women from 2002 to 2010: influences of publications, guidelines, marketing activities and policy.

PubMed

Peeters, Geeske; Tett, Susan E; Duncan, Emma L; Mishra, Gita D; Dobson, Annette J

2014-12-01

Developments in anti-osteoporosis medications (AOMs) have led to changes in guidelines and policy, which, along with media and marketing strategies, have had an impact upon the prescribing of AOM. The aim was to examine patterns of AOM dispensing in older women (aged 76-81 years at baseline) from 2002 to 2010. Administrative claims data were used to describe AOM dispensing in 4649 participants (born in 1921-1926 and still alive in 2011) in the Australian Longitudinal Study on Women's Health. The patterns were interpreted in the context of changes in guidelines, indications for subsidy, publications (scholarly and general media), and marketing activities. Total use of AOM increased from 134 DDD/1000/day in 2002 to 216 DDD/1000/day in 2007 but then decreased to 184 DDD/1000/day in 2010. Alendronate was the most commonly dispensed AOM but decreased from 2007, while use of risedronate (2002 onward), strontium ranelate (2007 onward) and zoledronic acid (2008 onward) increased. Etidronate and hormone replacement therapy (HRT) prescriptions gradually decreased over time. The decline in alendronate dispensing coincided with increases of other bisphosphonates and publicity about potential adverse effects of bisphosphonates, despite relaxing indications for bone density testing and subsidy for AOM. Overall dispense of AOM from 2002 reached a peak in 2007 and thereafter declined despite increases in therapeutic options and improved subsidised access. The recent decline in overall AOM dispensing seems to be explained largely by negative publicity rather than specific changes in guidelines and policy. Copyright © 2014 John Wiley & Sons, Ltd.

Otitis media in Greenland. Studies on historical, epidemiological, microbiological, and immunological aspects.

PubMed

Homøe, P

2001-01-01

This thesis describes the different aspects of otitis media (OM) in the population of Greenland viewed in a historical and modern clinical perspective. Chapter 1 outlines the addressed problems and aims while chapters 2 and 3 deal with historical studies and an evaluation of the present knowledge based on the literature. Physical anthropological studies, using skeletal samples of adult Eskimo crania from before and after the colonization of Greenland in 1721 and information about modern living Eskimos (Inuit), have shown that OM sequelae of the temporal bones were significantly less common in pre-colonization Eskimos and that the mean area size of the pneumatized cell system in the temporal bone was significantly larger in pre-colonization Eskimos. These findings indicated an increase in OM after the colonization most likely caused by the social, cultural, habitary, and dietary changes due to increased contact with the outside world. Historical reports after the colonization confirm a high prevalence of OM especially in children. Modern epidemiological studies from the 1960's to 1980's in the Arctic region of Alaska, Canada, and Greenland along with reports from visiting consultant otologists in Greenland almost uniformly mention prevalent OM problems in children as well as in adults. The aim was therefore to further describe the epidemiological pattern of the different OM disease entities (acute OM (AOM), chronic OM (COM), COM with suppuration (CSOM), secretory OM (SOM), and cholesteatoma) and investigate the potentially associated risk factors in especially Greenlandic children because these diseases are primarily established and problematical in childhood. Chapter 4 describes the definitions used in the thesis and chapter 5 describes the studies included. Section 5.1 describes a study of cholesteatoma in Greenlanders. The study revealed an almost similar incidence of hospital treated children with cholesteatoma (6.6 per 100,000) as seen in comparable studies from other parts of the world. Furthermore, childhood cholesteatomas were the most aggressive. The frequency of residuals or recurrences after otosurgical treatment was high with a trend for better results when using the extensive canal wall-down procedure. It could be concluded that these patients urgently need close follow-up for at least five years postoperatively, if not lifelong. Section 5.2 describes a hearing screening survey of 167 school children using school registration charts. A high prevalence of hearing loss (HL) was found. A total of 43% of the children had hearing thresholds exceeding 20 dB at one or more frequencies between 250-8000 Hz in one or both ears, and 19% had the same type of HL in the frequencies 500-2000 Hz. HL was significantly associated with episodes of OM. These findings were in accordance with reports from Alaska and Canada. It is therefore concluded that a hearing screening programme of school children is important and that OM seems to have an impact on hearing in school children in Greenland. In section 5.3 an epidemiological survey is described concerning the prevalence of the different OM disease entities. The survey was carried out in Nuuk and Sisimiut and involved 740 children aged 3, 4, 5, and 8 years. A total of 591 children participated and selection bias was not found when controlling for age, sex, and episodes of AOM. The survey revealed that 52% of children in Nuuk and 54% in Sisimiut had some kind of pathological affection of their middle ear. COM and CSOM were found in 9%, but more prevalent among children in Sisimiut (12%) than in Nuuk (7%). Middle ear effusion (MEE) diagnosed by tympanometry was found in 23% in Nuuk and 28% in Sisimiut while simple tubal dysfunction (STD) was found in 13% and 8%, respectively. MEE and STD were associated with young age. Sequelae of OM was apparent in 11% in both towns. When comparing the results with a 10-year-older, almost similar survey of 142 children, it was evident that the OM situation had not changed in the period between the studies. The survey underlines the need for increased focus on the different OM entities in Greenlandic children. Section 5.4 deals with microbiological aspects. The nasopharyngeal microflora and ear discharge microflora of potential pathogens were evaluated in 54 children with AOM and in 201 control children without AOM. Very high carriage rates expressed qualitatively and semiquantitatively of potentially pathogenio bacteria were found in the nasopharynx of children with AOM (98%) but also in that of the control children (91%) and even in children denoted as being very healthy (94%). However, the same bacterial species were cultured from the nasopharynx and ear discharge as in comparable studies world-wide. Only S. pneumoniae was carried significantly more often in the nasopharynx of AOM children compared with age matched control children. Chlamydiae, M. pneumoniae, adenovirus, respiratory syncytial virus, parainfluenza- type 1, 2, and 3 virus, and influenza- type A and B virus were not major pathogens. In contrast, entero- and rhinoviruses were detected significantly more frequent in nasopharyngeal specimens from AOM children (59%) compared with age matched controls (33%) and also in 29% of the examined ear discharge specimens. It is therefore concluded that the potentially pathogenic bacterial load is early and massive. This alone or in interplay with entero- and rhinovirus infection and occasionally with other viruses may play an important role in the high prevalence of OM among children in Greenland. Section 5.5 deals with an examination of potential risk factors for AOM, recurrent AOM (rAOM), and COM in the same 591 children as studied in section 5.3. Early age at first AOM episode was associated with rAOM episodes (> or = 5 episodes since birth). Thus, the relative risk of developing rAOM was eight times higher if the first episode of AOM occurred before 7 months of age than after 24 months of age. Furthermore, compared with studies elsewhere in the world, a high proportion (40%) of the children in this survey had their first AOM episode during their first year of life and 41% of these children developed rAOM. It was also found that children had an increased risk of AOM, rAOM, or COM when both parents were born in Greenland, when parents also have had OM, when living in very crowded households, and when having experienced a long period of exclusive breast feeding, or when recalling of breast feeding was not possible. Gender, type, and size of housing, insulation standard of housing, daycare, exposure to passive cigarette smoking, and dietary habits were not associated with AOM, rAOM, or COM in the surveyed children. It is concluded that early onset of AOM occurs frequently in Greenlandic children and that a high proportion of these children develop rAOM. The study confirms that AOM is a highly multifactorial disease determined by a number of genetic and environmental factors. Finally, section 5.6 is a hypothesis generating study attempting to explain the high prevalence of early episodes of AOM in community-based children in Nuuk. The hypothesis is based on a possible association between findings of mannose-binding lectin genotypes, early Epstein-Barr virus infections and episodes of AOM, rAOM, or nasopharyngeal colonization with potentially pathogenic bacteria. However, the study does not support any of this hypothesis. In chapter 6, future studies are suggested and chapter 7 presents concluding remarks.

Pediatricians' attitudes in management of acute otitis media and ear pain in Turkey.

PubMed

Büyükcam, Ayşe; Kara, Ateş; Bedir, Tuğba; Gülhan, Belgin; Özdemir, Halil; Sütçü, Murat; Düzgöl, Mine; Arslan, Aslı; Tekin, Tuna; Çelebi, Solmaz; Kukul, Musa Gürel; Bayhan, Gülsüm İclal; Köşker, Muhammet; Karbuz, Adem; Çelik, Melda; Kocabay Sütçü, Zümrüt; Metin, Özge; Karakaşlılar, Sebahat; Dağlı, Abdullah; Kara, Soner Sertan; Albayrak, Eda; Kanık, Saliha; Tezer, Hasan; Parlakay, Aslınur; Çiftci, Ergin; Somer, Ayper; Devrim, İlker; Kurugöl, Zafer; Dinleyici, Ener Çağrı; Atla, Pınar

2018-04-01

Acute otitis media (AOM) is predominantly a disease of childhood and one of the common reasons for prescribing antibiotics. Ear pain is the main symptom of AOM, with the result that parents frequently seek immediate medical assistance for their children. Antibiotic therapy for AOM does not provide symptomatic relief in the first 24 hours, and analgesics are commonly recommended for relieving the pain associated with AOM. The aims of the present study were to assess pediatricians' attitudes toward AOM and ear pain management in Turkey. This multicenter descriptive questionnaire study was conducted in 20 centers from different geographic locations in Turkey, with 977 pediatricians, between June 2015 and December 2016. The questionnaire comprised 20 questions focusing on the pediatricians' sociodemographic variables, experiences, and treatment related to AOM and ear pain. Of the pediatricians, 58.2% were residents, 36.5% were specialists, and 4.3% were lecturers. Most participants were working in a university hospital (54.8%) or education and research hospital (32.2%). In general daily practice, the AOM diagnosis rates were between 6% and 20% in outpatient clinics, and 52.3% of the participants stated the patients complained about ear pain in pediatric clinics. The watchful waiting (WW) rate, as opposed to immediate antibiotic treatment, was 39.8% for all the pediatricians. The pediatric residents used the WW strategy less than the specialists and lecturers did (p = 0.004). The rates of the WW strategy were higher in outpatient clinics where AOM was commonly diagnosed (p < 0.001). The most common antibiotic prescribed for AOM was amoxicillin clavulanate (76.7%). The mean recommended treatment period for AOM was 9.3 ± 2.2 days. The choices for systemic ear pain treatment were acetaminophen (26.8%), ibuprofen (29.4%), and alternating between ibuprofen and acetaminophen (43.9%). Moreover, 34.6% of the participants recommended topical agents for otalgia. Topical agents were more commonly recommended by the pediatric residents than specialists or lecturers (p < 0.001). Finally, 58.3% of pediatricians had experiences of the parents' usage of a variety of herbal and folk remedies, such as breast milk or olive oil, for their children's ear pain. Amoxicillin clavulanate was the most frequently prescribed antibiotic for AOM. WW was approved by the pediatricians, and having more AOM patients was a significant factor in the physicians' choice of WW; nevertheless, the WW rate was poor. Implementation of educational intervention strategies will help pediatricians in improving their compliance with evidence-based guidelines for AOM treatment. Otalgia is taken seriously by parents and pediatricians, and otalgia treatment seems to be well accepted in Turkey for providing symptomatic relief and enhancing the patients' quality of life. Copyright © 2018 Elsevier B.V. All rights reserved.

The potential for biologically catalyzed anaerobic methane oxidation on ancient Mars.

PubMed

Marlow, Jeffrey J; Larowe, Douglas E; Ehlmann, Bethany L; Amend, Jan P; Orphan, Victoria J

2014-04-01

This study examines the potential for the biologically mediated anaerobic oxidation of methane (AOM) coupled to sulfate reduction on ancient Mars. Seven distinct fluids representative of putative martian groundwater were used to calculate Gibbs energy values in the presence of dissolved methane under a range of atmospheric CO2 partial pressures. In all scenarios, AOM is exergonic, ranging from -31 to -135 kJ/mol CH4. A reaction transport model was constructed to examine how environmentally relevant parameters such as advection velocity, reactant concentrations, and biomass production rate affect the spatial and temporal dependences of AOM reaction rates. Two geologically supported models for ancient martian AOM are presented: a sulfate-rich groundwater with methane produced from serpentinization by-products, and acid-sulfate fluids with methane from basalt alteration. The simulations presented in this study indicate that AOM could have been a feasible metabolism on ancient Mars, and fossil or isotopic evidence of this metabolic pathway may persist beneath the surface and in surface exposures of eroded ancient terrains.

Anaerobic oxidation of methane in sediments of two boreal lakes

NASA Astrophysics Data System (ADS)

Rissanen, Antti J.; Karvinen, Anu; Nykänen, Hannu; Mpamah, Promise; Peura, Sari; Tiirola, Marja; Kankaala, Paula

2014-05-01

Anaerobic oxidation of methane (AOM) is a considerable sink for methane (CH4) in marine systems, but very little is known about the occurrence and importance of the process in freshwater systems. In addition, much about the microbial communities involved in AOM is unclear. AOM coupled with sulfate reduction is the dominant AOM process in marine systems but the scarce existing data suggest that, in freshwater systems, AOM coupled with reduction of alternative electron acceptors (nitrate/nitrite, manganese, iron) is more important. In this study, potential for AOM coupled with metal reduction was studied in boreal lake sediments. Slurries of sediment samples collected from two sites in southeastern Finland, i.e. from Lake Orivesi, Heposelkä, an vegetated littoral site, dominated by Phragmites australis (Sample Sa, sediment layer 0 - 25 cm) and from the profundal zone of a mesotrophic Lake Ätäskö (Aa, 0 - 10 cm; Ab, 10 - 30 cm; Ac, 90 - 130 cm), were incubated in laboratory in anaerobic conditions at in situ temperatures for up to 5 months. The samples were amended either 1) with 13CH4, 2) 13CH4 + manganese(II) oxide (MnO) or 3) 13CH4 + iron(III) hydroxide (Fe(OH)3), and the processes were measured by following the 13C transfer to the carbon dioxide (CO2) pool and by concentration measurements of CH4 and CO2. Changes in microbial communities were studied from DNA extracted from sediment samples before and after incubation period by next-generation sequencing (Ion Torrent) of polymerase chain reaction (PCR) - amplified bacterial and archaeal 16S rRNA and methyl coenzyme-M reductase gene (mcrA) amplicons. Increase in 13C of CO2 gas confirmed that AOM took place in sediments of both study lakes. In general, 13CO2 - production was significant both at the beginning (0 - 21 days) and at the end (84 - 151 days) of incubation period. Potential AOM rates (calculated based on 13CO2 - production) varied considerably and were much lower in deep sediment (Sample Ac), 0.1 - 0.2 nmol CH4 d-1gwetsediment-1, than in surface sediment samples (Samples Aa, Ab and Sa), 0.2 - 12.3 nmol CH4 d-1gwetsediment-1. AOM took place without metal additions in every sample type. Addition of MnO increased potential AOM rates in surface sediment samples but not in deep sediment samples. Addition of Fe(OH)3increased AOM significantly only in Aa samples. Molecular microbiological analyses are currently in progress and the results will be shown in the poster presentation.

Tetrahydrocurcumin is more effective than curcumin in preventing azoxymethane-induced colon carcinogenesis.

PubMed

Lai, Ching-Shu; Wu, Jia-Ching; Yu, Shih-Feng; Badmaev, Vladimir; Nagabhushanam, Kalyanam; Ho, Chi-Tang; Pan, Min-Hsiung

2011-12-01

Tetrahydrocurcumin (THC), a major metabolite of curcumin (CUR), has been demonstrated to be anti-cancerogenic and anti-angiogenic and prevents type II diabetes. In this present study, we investigated the chemopreventive effects and underlying molecular mechanisms of dietary administration of CUR and THC in azoxymethane (AOM)-induced colon carcinogenesis in mice. All mice were sacrificed at 6 and 23 wk, and colonic tissue was collected and examined. We found that dietary administration of both CUR and THC could reduce aberrant crypt foci and polyps formation, while THC showed a better inhibitory effect than CUR. At the molecular level, results from Western blot analysis and immunohistochemistry staining showed that dietary CUR and THC exhibited anti-inflammatory activity by decreasing the levels of inducible NOS and COX-2 through downregulation of ERK1/2 activation. In addition, both dietary CUR and THC significantly decreased AOM-induced Wnt-1 and β-catenin protein expression, as well as the phosphorylation of GSK-3β in colonic tissue. Moreover, dietary feeding with CUR and THC markedly reduced the protein level of connexin-43, an important molecule of gap junctions, indicating that both CUR and THC might interfer with the intercellular communication of crypt cells. Taken together, these results demonstrated for the first time the in vivo chemopreventive efficacy and molecular mechanisms of dietary THC against AOM-induced colonic tumorigenesis. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Homeopathic Medications as Clinical Alternatives for Symptomatic Care of Acute Otitis Media and Upper Respiratory Infections in Children

PubMed Central

Boyer, Nancy N

2013-01-01

The public health and individual risks of inappropriate antibiotic prescribing and conventional over-the-counter symptomatic drugs in pediatric treatment of acute otitis media (AOM) and upper respiratory infections (URIs) are significant. Clinical research suggests that over-the-counter homeopathic medicines offer pragmatic treatment alternatives to conventional drugs for symptom relief in children with uncomplicated AOM or URIs. Homeopathy is a controversial but demonstrably safe and effective 200-year-old whole system of complementary and alternative medicine used worldwide. Numerous clinical studies demonstrate that homeopathy accelerates early symptom relief in acute illnesses at much lower risk than conventional drug approaches. Evidence-based advantages for homeopathy include lower antibiotic fill rates during watchful waiting in otitis media, fewer and less serious side effects, absence of drug-drug interactions, and reduced parental sick leave from work. Emerging evidence from basic and preclinical science research counter the skeptics' claims that homeopathic remedies are biologically inert placebos. Consumers already accept and use homeopathic medicines for self care, as evidenced by annual US consumer expenditures of $2.9 billion on homeopathic remedies. Homeopathy appears equivalent to and safer than conventional standard care in comparative effectiveness trials, but additional well-designed efficacy trials are indicated. Nonetheless, the existing research evidence on safety supports pragmatic use of homeopathy in order to “first do no harm” in the early symptom management of otherwise uncomplicated AOM and URIs in children. PMID:24381823

Homeopathic medications as clinical alternatives for symptomatic care of acute otitis media and upper respiratory infections in children.

PubMed

Bell, Iris R; Boyer, Nancy N

2013-01-01

The public health and individual risks of inappropriate antibiotic prescribing and conventional over-the-counter symptomatic drugs in pediatric treatment of acute otitis media (AOM) and upper respiratory infections (URIs) are significant. Clinical research suggests that over-the-counter homeopathic medicines offer pragmatic treatment alternatives to conventional drugs for symptom relief in children with uncomplicated AOM or URIs. Homeopathy is a controversial but demonstrably safe and effective 200-year-old whole system of complementary and alternative medicine used worldwide. Numerous clinical studies demonstrate that homeopathy accelerates early symptom relief in acute illnesses at much lower risk than conventional drug approaches. Evidence-based advantages for homeopathy include lower antibiotic fill rates during watchful waiting in otitis media, fewer and less serious side effects, absence of drug-drug interactions, and reduced parental sick leave from work. Emerging evidence from basic and preclinical science research counter the skeptics' claims that homeopathic remedies are biologically inert placebos. Consumers already accept and use homeopathic medicines for self care, as evidenced by annual US consumer expenditures of $2.9 billion on homeopathic remedies. Homeopathy appears equivalent to and safer than conventional standard care in comparative effectiveness trials, but additional well-designed efficacy trials are indicated. Nonetheless, the existing research evidence on safety supports pragmatic use of homeopathy in order to "first do no harm" in the early symptom management of otherwise uncomplicated AOM and URIs in children.

Impact of the Interaction between Aquatic Humic Substances and Algal Organic Matter on the Fouling of a Ceramic Microfiltration Membrane.

PubMed

Zhang, Xiaolei; Fan, Linhua; Roddick, Felicity A

2018-02-01

The influence of the interaction between aquatic humic substances and the algal organic matter (AOM) derived from Microcystis aeruginosa on the fouling of a ceramic microfiltration (MF) membrane was studied. AOM alone resulted in a significantly greater flux decline compared with Suwannee River humic acid (HA), and fulvic acid (FA). The mixture of AOM with HA and FA exhibited a similar flux pattern as the AOM alone in the single-cycle filtration tests, indicating the flux decline may be predominantly controlled by the AOM in the early filtration cycles. The mixtures resulted in a marked increase in irreversible fouling resistance compared with all individual feed solutions. An increase in zeta potential was observed for the mixtures (becoming more negatively charged), which was in accordance with the increased reversible fouling resistance resulting from enhanced electrostatic repulsion between the organic compounds and the negatively-charged ceramic membrane. Dynamic light scattering (DLS) and size exclusion chromatography analyses showed an apparent increase in molecular size for the AOM-humics mixtures, and some UV-absorbing molecules in the humics appeared to participate in the formation of larger aggregates with the AOM, which led to greater extent of pore plugging and hence resulted in higher irreversible fouling resistance.

Impact of the Interaction between Aquatic Humic Substances and Algal Organic Matter on the Fouling of a Ceramic Microfiltration Membrane

PubMed Central

Zhang, Xiaolei; Fan, Linhua

2018-01-01

The influence of the interaction between aquatic humic substances and the algal organic matter (AOM) derived from Microcystis aeruginosa on the fouling of a ceramic microfiltration (MF) membrane was studied. AOM alone resulted in a significantly greater flux decline compared with Suwannee River humic acid (HA), and fulvic acid (FA). The mixture of AOM with HA and FA exhibited a similar flux pattern as the AOM alone in the single-cycle filtration tests, indicating the flux decline may be predominantly controlled by the AOM in the early filtration cycles. The mixtures resulted in a marked increase in irreversible fouling resistance compared with all individual feed solutions. An increase in zeta potential was observed for the mixtures (becoming more negatively charged), which was in accordance with the increased reversible fouling resistance resulting from enhanced electrostatic repulsion between the organic compounds and the negatively-charged ceramic membrane. Dynamic light scattering (DLS) and size exclusion chromatography analyses showed an apparent increase in molecular size for the AOM-humics mixtures, and some UV-absorbing molecules in the humics appeared to participate in the formation of larger aggregates with the AOM, which led to greater extent of pore plugging and hence resulted in higher irreversible fouling resistance. PMID:29389873

Is mother-child transmission a possible vehicle for xylitol prophylaxis in acute otitis media?

PubMed

Danhauer, Jeffrey L; Kelly, Allison; Johnson, Carole E

2011-10-01

Xylitol can be a prophylaxis for acute otitis media (AOM), especially when administered via chewing gum, but that vehicle has limitations for children. This review sought evidence for links of mother-child transmission of bacteria and as a vehicle for xylitol as a prophylaxis for dental caries and its translation to AOM in infants and young children. Qualitative systematic review. Combining output from 43 search strings used earlier and submitting 20 new strings to PubMed resulted in 14 studies (six were excluded; eight were included). Included studies had to be published in English-language, peer-reviewed journals; involve mothers using xylitol; and assess bacteria or caries in their children. Evaluation forms were completed for search, retrieval, and quality assessment of included studies. The studies showed that mothers' chewing xylitol gum was a prophylaxis against bacteria and caries in their children. A mother-child transmission model was presented as a possible vehicle for use in comprehensive prevention programs for AOM. Potential for xylitol use to prevent AOM warrants further study. A mother-child model may apply to AOM for transmission of bacteria and as a prophylaxis, but alternative vehicles like nasal sprays should be investigated for ease of use and effectiveness.

Iron-mediated anaerobic oxidation of methane in brackish coastal sediments.

PubMed

Egger, Matthias; Rasigraf, Olivia; Sapart, Célia J; Jilbert, Tom; Jetten, Mike S M; Röckmann, Thomas; van der Veen, Carina; Bândă, Narcisa; Kartal, Boran; Ettwig, Katharina F; Slomp, Caroline P

2015-01-06

Methane is a powerful greenhouse gas and its biological conversion in marine sediments, largely controlled by anaerobic oxidation of methane (AOM), is a crucial part of the global carbon cycle. However, little is known about the role of iron oxides as an oxidant for AOM. Here we provide the first field evidence for iron-dependent AOM in brackish coastal surface sediments and show that methane produced in Bothnian Sea sediments is oxidized in distinct zones of iron- and sulfate-dependent AOM. At our study site, anthropogenic eutrophication over recent decades has led to an upward migration of the sulfate/methane transition zone in the sediment. Abundant iron oxides and high dissolved ferrous iron indicate iron reduction in the methanogenic sediments below the newly established sulfate/methane transition. Laboratory incubation studies of these sediments strongly suggest that the in situ microbial community is capable of linking methane oxidation to iron oxide reduction. Eutrophication of coastal environments may therefore create geochemical conditions favorable for iron-mediated AOM and thus increase the relevance of iron-dependent methane oxidation in the future. Besides its role in mitigating methane emissions, iron-dependent AOM strongly impacts sedimentary iron cycling and related biogeochemical processes through the reduction of large quantities of iron oxides.

Topical vs. systemic treatments for acute otitis media.

PubMed

Thornton, Kathy; Parrish, Francie; Swords, Christine

2011-01-01

Acute otitis media (AOM) is a common condition in children that is often treated with systemic antibiotic therapy; however, research suggests that non-complicated AOM will resolve spontaneously using only eardrops. To determine best practice for the use of systematic antibiotics compared to topical treatment of AOM, a systematic review of evidence was conducted. Cochrane, Medline, CINAHL, and other databases were searched. Inclusion criteria were studies published from 1995-2010 that included children with AOM and were randomized controlled trials (RCTs). Five systematic reviews and five RCTs were included in the review. Current evidence recommends using topical and other alternative approaches for treating non-complicated AOM in children 2 years of age or older; however, many practitioners are not currently following these recommendations for various reasons. Additional research to address these reasons may help determine how to improve practitioner adherence to best practice evidence and guidelines to help reduce the unnecessary use of systemic antibiotics.

Effect of nitrogen/phosphorus concentration on algal organic matter generation of the diatom Nitzschia palea: Total indicators and spectroscopic characterization.

PubMed

Han, Linlin; Xu, Bingbing; Qi, Fei; Chen, Zhonglin

2016-09-01

Critical algal blooms in great lakes increase the level of algal organic matters (AOMs), significantly altering the composition of natural organic matters (NOMs) in freshwater of lake. This study examined the AOM's characteristics of Nitzschia palea (N. palea), one kind of the predominant diatom and an important biomarker of water quality in the great lakes of China, to investigate the effect of AOMs on the variation of NOMs in lakes and the process of algal energy. Excitation-emission matrix fluorescence (EEM) spectroscopy, synchronous fluorescence (SF) spectroscopy and deconvolution UV-vis (D-UV) spectroscopy were utilized to characterize AOMs to study the effects of nutrient loading on the composition change of AOMs. From results, it was revealed that the phosphorus is the limiting factor for N. palea's growth and the generation of both total organic carbon and amino acids but the nitrogen is more important for the generation of carbohydrates and proteins. EEM spectra revealed differences in the composition of extracellular organic matter and intracellular organic matter. Regardless of the nitrogen and phosphorus concentrations, aromatic proteins and soluble microbial products were the main components, but the nitrogen concentration had a significant impact on their composition. The SF spectra were used to study the AOMs for the first time and identified that the protein-like substances were the major component of AOMs, creating as a result of aromatic group condensation. The D-UV spectra showed carboxylic acid and esters were the main functional groups in the EOMs, with -OCH3, -SO2NH2, -CN, -NH2, -O- and -COCH3 functional groups substituting into benzene rings. Copyright © 2016. Published by Elsevier B.V.

Relationship of environmental tobacco smoke to otitis media (OM) in children.

PubMed

Csákányi, Zsuzsanna; Czinner, Antal; Spangler, John; Rogers, Todd; Katona, Gábor

2012-07-01

Many, but not all, studies have found a correlation between environmental tobacco smoke (ETS) and acute otitis media (AOM) and other adverse otologic outcomes. Given its high personal and societal costs and the divergent findings of the effect of ETS on middle ear disease, the aim of the current study was to assess the impact and possible determinant factors of ETS on recurrent (two or more) episodes of AOM. The study was performed at Heim Pal Children's Hospital, Ear, Nose and Throat (ENT) Department, Budapest, Hungary. Caregivers of a convenience sample of 412 children attending the ENT outpatient clinic were surveyed via a 22-item questionnaire regarding demographics, socioeconomics, and smoking behaviours of the child's family; as well as care-givers' self report of the number of AOM episodes of the child. Of the 412 participants, 155 (38%) children's parents smoked. In bivariate analysis, two or more episodes of AOM correlated with reported hearing problems, day care enrolment, parental employment and increased age of the child. In multivariate logistic regression, parental smoking more than doubled a child's risk for recurrent AOM while increased maternal employment (e.g. part-time or full-time versus unemployed) boosted risk up to fourfold. Among children whose parents smoked, half-packs of cigarettes smoked per day and day care attendance doubled or nearly tripled, respectively, the risk of recurrent AOM episodes. Childhood exposure to ETS is high among an ENT clinic population of Hungarian children. Such exposure correlates with AOM episodes, ENT operations and conductive hearing loss. Data such as these argue for strict laws smoke-free laws not only in Hungary, but also in Europe and around the world. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Incidence and economic burden of acute otitis media in children aged up to 5years in three Middle Eastern countries and Pakistan: A multinational, retrospective, observational study.

PubMed

Mustafa, Ghulam; Al Aidaroos, Amal Y; Al Abaidani, Idris S; Meszaros, Kinga; Gopala, Kusuma; Ceyhan, Mehmet; Al-Tannir, Mohamad; DeAntonio, Rodrigo; Bawikar, Shyam; Schmidt, Johannes E

2017-06-01

Epidemiological data on acute otitis media (AOM), an infectious disease frequently affecting children, are lacking in some countries. This study was undertaken to assess the incidence of AOM in children ≤5years in Saudi Arabia, Oman, Pakistan, and Turkey, as well as the economic burden from a parent/caregiver perspective. Medical records of 4043 children (Saudi Arabia=1023, Oman=998, Pakistan=1022, Turkey=1000) were retrospectively reviewed and the incidence of AOM episodes calculated from suspected and confirmed cases. Using a standardized Health Economics Questionnaire, parents recorded resource use and expenses incurred per AOM episode [in local currency and converted to US dollars (USD)]. The overall incidence of AOM episodes per 1000 person-years was: Saudi Arabia, 207 [95% confidence interval (CI): 178-238]; Oman, 105 (95% CI: 85-127); Pakistan, 138 (95% CI: 116-163); and Turkey, 99 (95% CI: 79-123). The mean total out-of-pocket healthcare expense incurred by parents/caregivers per episode was: Saudi Arabia USD67.1 [standard deviation (SD)=93.0], Oman USD16.1 (SD=16.4), Pakistan USD22.1 (SD=20.5), and Turkey USD33.6 (SD=44.9). The incidence of AOM episodes varied across all four countries, probably due to different diagnostic and management practices. Nevertheless, our results confirm that AOM causes a substantial burden to public health, reinforcing the need for cost-effective prevention strategies. Copyright © 2017 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

Formation of organic chloramines during chlor(am)ination and UV/chlor(am)ination of algae organic matter in drinking water.

PubMed

Zhang, Tian-Yang; Lin, Yi-Li; Xu, Bin; Cheng, Tuo; Xia, Sheng-Ji; Chu, Wen-Hai; Gao, Nai-Yun

2016-10-15

Surface water are frequently subjected to problems of algal blooms and release of algae organic matter (AOM) from the algae cells, which cause many water quality issues. This study investigated the formation of organic chloramines and nitrogenous disinfection by-products (N-DBPs) during chlor(am)ination and UV/chlor(am)ination of AOM in drinking water. AOM caused higher organic chloramine formation than humic acid and fulvic acid during chlor(am)ination. The formation of organic chloramines increased first and then decreased with the increase of free chlorine dosage, but kept increasing with the increase of NH2Cl dosage. During AOM chlorination, the formation of organic chloramines kept decreasing as the reaction time went by, and the maximum organic chloramine proportion (79.1%) in total chlorine occurred at 8 h. However, during AOM chloramination, the formation of organic chloramines increased first, decreased in the following and then increased again as the reaction time went by, and the maximum organic chloramine proportion (22.1%) in total chlorine occurred at 24 h. UV irradiation pretreatment did not effectively influence organic chloramine formation during AOM chlor(am)ination, but accelerated the degradation of organic chloramines during chloramination. Besides, UV pretreatment enhanced the formation of N-DBPs during the subsequent chlor(am)ination of AOM, especially dichloroacetonitrile. Copyright © 2016 Elsevier Ltd. All rights reserved.

Treatment of acute otitis media consensus recommendations.

PubMed

Hoberman, Alejandro; Marchant, Colin D; Kaplan, Sheldon L; Feldman, Sandor

2002-01-01

The objective of this paper is to provide consensus recommendations for the management of acute otitis media (AOM) that pediatricians can incorporate into their daily practices. These recommendations were developed during a roundtable meeting that convened clinicians versed in the management of AOM. This meeting was sponsored by an educational grant from SmithKline Beecham Pharmaceuticals. In addition, clinical studies on AOM identified via MEDLINE search were considered in the development of these recommendations. The Drug-Resistant Streptococcus pneumoniae Therapeutic Working Group guidelines for the management of AOM are reviewed in detail. All of the articles identified from the data sources were evaluated and all information deemed relevant was included in this review. AOM is one of the most common infectious diseases affecting infants and children and one of the leading causes of office visits and antibiotic prescriptions for this population. The incidence of AOM has increased during the past 25 years, probably the result of an increased utilization of day care facilities in the United States. The predominant pathogens in AOM include S. pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The high prevalence of drug-resistant S. pneumoniae and beta-lactamase-producing organisms presents a clinical challenge for practitioners in the selection of empiric antimicrobial therapy. Pharmacokinetic/pharmacodynamic principles should be considered in addition to minimum inhibitory concentrations in selecting antibiotics for AOM. Amoxicillin at conventional or high doses (80-90 mg/kg/day) remains an appropriate choice for first-line therapy for AOM. For patients in whom amoxicillin is unsuccessful, second-line therapy should have demonstrated activity against penicillin-resistant S. pneumoniae as well as beta-lactamase-producing pathogens. Appropriate options for second-line therapy include high-dose amoxicillin/clavulanate (90 mg/kg/day based on the amoxicillin component) and ceftriaxone. Cefuroxime has been suggested as a second-line agent in the past, but recent surveillance data suggest it may no longer be active against penicillin-resistant strains of S. pneumoniae. Tympanocentesis is useful for identifying the causative pathogen, and it may be beneficial for patients who have failed multiple courses of antibiotics. The pneumococcal conjugate vaccine recently was approved for use in children and should be administered to all children less than 2 years old and those at risk for recurrent AOM (e.g., day care attendance, siblings with a history of recurrent AOM). Consensus recommendations are provided for the management of AOM, with a focus on antimicrobial therapy. The current challenges in the management of AOM include the need for an increased understanding of epidemiology, increasing resistance among common middle ear pathogens, use of pharmacokinetic/pharmacodynamic principles in designing treatment strategies, and understanding the potential impact of the pneumococcal conjugate vaccine.

Mechanisms of colitis-accelerated colon carcinogenesis and its prevention with the combination of aspirin and curcumin: Transcriptomic analysis using RNA-seq.

PubMed

Guo, Yue; Su, Zheng-Yuan; Zhang, Chengyue; Gaspar, John M; Wang, Rui; Hart, Ronald P; Verzi, Michael P; Kong, Ah-Ng Tony

2017-07-01

Colorectal cancer (CRC) remains the leading cause of cancer-related death in the world. Aspirin (ASA) and curcumin (CUR) are widely investigated chemopreventive candidates for CRC. However, the precise mechanisms of their action and their combinatorial effects have not been evaluated. The purpose of the present study was to determine the effect of ASA, CUR, and their combination in azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-accelerated colorectal cancer (CAC). We also aimed to characterize the differential gene expression profiles in AOM/DSS-induced tumors as well as in tumors modulated by ASA and CUR using RNA-seq. Diets supplemented with 0.02% ASA, 2% CUR or 0.01% ASA+1% CUR were given to mice from 1week prior to the AOM injection until the experiment was terminated 22weeks after AOM initiation. Our results showed that CUR had a superior inhibitory effect in colon tumorigenesis compared to that of ASA. The combination of ASA and CUR at a lower dose exhibited similar efficacy to that of a higher dose of CUR at 2%. RNA isolated from colonic tissue from the control group and from tumor samples from the experimental groups was subjected to RNA-seq. Transcriptomic analysis suggested that the low-dose combination of ASA and CUR modulated larger gene sets than the single treatment. These differentially expressed genes were situated in several canonical pathways important in the inflammatory network and liver metastasis in CAC. We identified a small subset of genes as potential molecular targets involved in the preventive action of the combination of ASA and CUR. Taken together, the current results provide the first evidence in support of the chemopreventive effect of a low-dose combination of ASA and CUR in CAC. Moreover, the transcriptional profile obtained in our study may provide a framework for identifying the mechanisms underlying the carcinogenesis process from normal colonic tissue to tumor development as well as the cancer inhibitory effects and potential molecular targets of ASA and CUR. Copyright © 2017 Elsevier Inc. All rights reserved.

Motion of tympanic membrane in guinea pig otitis media model measured by scanning laser Doppler vibrometry.

PubMed

Wang, Xuelin; Guan, Xiying; Pineda, Mario; Gan, Rong Z

2016-09-01

Otitis media (OM) is an inflammatory or infectious disease of the middle ear. Acute otitis media (AOM) and otitis media with effusion (OME) are the two major types of OM. However, the tympanic membrane (TM) motion differences induced by AOM and OME have not been quantified in animal models in the literature. In this study, the guinea pig AOM and OME models were created by transbullar injection of Streptococcus pneumoniae type 3 and lipopolysaccharide, respectively. To explore the effects of OM on the entire TM vibration, the measurements of full-field TM motions were performed in the AOM, OME and untreated control ears by using scanning laser Doppler vibrometry (SLDV). The results showed that both AOM and OME generally reduced the displacement peak and produced the traveling-wave-like motions at relatively low frequencies. Compared with the normal ear, OME resulted in a significant change of the TM displacement mainly in the inferior portion of the TM, and AOM significantly affected the surface motion across four quadrants. The SLDV measurements provide more insight into sound-induced TM vibration in diseased ears. Copyright © 2016 Elsevier B.V. All rights reserved.

Will parents participate in and comply with programs and regimens using xylitol for preventing acute otitis media in their children?

PubMed

Danhauer, Jeffrey L; Johnson, Carole E; Baker, Jason A; Ryu, Jung A; Smith, Rachel A; Umeda, Claire J

2015-04-01

Antiadhesive properties in xylitol, a natural sugar alcohol, can help prevent acute otitis media (AOM) in children by inhibiting harmful bacteria from colonizing and adhering to oral and nasopharyngeal areas and traveling to the Eustachian tube and middle ear. This study investigated parents' willingness to use and comply with a regimen of xylitol for preventing AOM in their preschool- and kindergarten-aged children. An Internet questionnaire was designed and administered to parents of young children in preschool and kindergarten settings. Most parents were unaware of xylitol's use for AOM and would not likely comply with regimens for preventing AOM in their children; however, parents having previous knowledge of xylitol and whose children had a history of AOM would be more likely to do so. Generally, most of these parents did not know about xylitol and probably would not use it to prevent ear infections. Unfortunately, these results parallel earlier findings for teachers and schools, which present obstacles for establishing ear infection prevention programs using similar protocols for young children. The results showed that considerable education and age-appropriate vehicles for administering xylitol are needed before establishing AOM prevention programs in schools and/or at home.

The effect of pneumococcal conjugate vaccines on incidence and microbiology associated with complicated acute otitis media.

PubMed

Laursen, B B; Danstrup, C S; Hoffmann, S; Nørskov-Lauritsen, N; Christensen, A L B; Ovesen, T

2017-10-01

The objectives of this study were to investigate the incidence of complicated acute otitis media (cAOM) as well as the associated microbiology before and after introduction of the 7- and 13-valent pneumococcal conjugate vaccines (PCV-7 and -13), respectively. CAOM comprises "heavy" AOM (AOM demanding hospitalization), mastodismus (M) and acute mastoiditis (AM). A retrospective cohort study of the incidence and microbiology associated with cAOM during the non-PCV era, the PCV-7 and 13 eras, respectively. Clinical and microbiological data were prospectively registered in a local database. The incidences of cAOM as well as the distribution of various bacterial strains in the three eras were compared. A total of 246 cases of cAOM (125 in the pre-vaccine period (2001-2006), 50 in the PCV-7 period (2007-2010) and 71 in the PCV-13 period (2011-2015)) were identified. The incidence of hAOM decreased by 62% in the PCV7-era but increased to almost pre-vaccine levels in the PCV-13 era. In the M + AM group, a decrease by almost 21% in the PCV7-era was found compared to the pre vaccine era, whereas the decrease was only 12% in the PCV13-era. The three most common findings in both hAOM and M + AM were Streptococcus pneumonia (SP), group A streptococcus (GAS) and "no growth". In the hAOM group, SP decreased from 38% in the pre-vaccine era to 31% in the PCV7-era and further to 16% in the PCV13-era. GAS decreased from 17% in the pre-vaccine era to 0% in the PCV7-era and 16% in the PCV13-era. The percentage of "no growth" increased from 12% to 38% and 44%, respectively. In the M + AM group, SP decreased to 10% in the PCV13-era compared with 44% in the pre-vaccine era and 41% in the PCV7-era. An increase in GAS from 15% in the pre-vaccine era and PCV7-era to 30% in the PCV13-era was observed. The "no growth" percentage increased from 13% in the pre-vaccine era to 26% in the PCV7-era and 33% in the PCV13-era. Introduction of PCV7 and PCV13 has been associated with an overall reduction of cAOM in Central Region Denmark. Pneumococci were still one of the two most common bacteria species related to cAOM though a decrease in pneumococci positive cases was observed. We found an increase in M + AM induced by GAS and a relatively large increase in "no growth", which might be caused by a more aggressive pre-hospital approach to treatment with antibiotics. Consequently, it is not evident whether the reduction of incidences is caused by the vaccines or a more aggressive antimicrobial attitude to manage AOM. The shift to GAS from SP is worrisome, and therefore continuous surveillance of the microbiology associated with AOM is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.

Epidemiological and microbiological characteristics of culture-proven acute otitis media in Taiwanese children.

PubMed

Chiu, Nan-Chang; Lin, Hsin-Yi; Hsu, Chyong-Hsin; Huang, Fu-Yuan; Lee, Kuo-Sheng; Chi, Hsin

2012-10-01

Acute otitis media (AOM) is one of the most common diseases in children. Here, we describe the epidemiological and microbiological characteristics of AOM in Taiwanese children over a 10-year period. We retrospectively enrolled pediatric patients with culture-proven AOM who were treated at Mackay Memorial Hospital, Taipei between 1999-2008. The data include demographic characteristics, clinical history, and microbiological characteristics. Six hundred and fourteen patients were included. The male:female ratio was 1.4 (p<0.001). Greater than three-fourths of the patients (476 [77.5%]) were < 5 years of age, and most patients were 1-2 years of age. The most common isolated pathogen was Streptococcus pneumoniae (419 patients [68.2%]), followed by nontypeable Haemophilus influenzae (NTHi; 118 patients [19.2%]). The distributions of age, gender, use of tympanocentesis, history of previous AOM, and use of antibiotic between patients infected with the two pathogens were not significantly different. However, the number of patients with AOM caused by S. pneumoniae, but not NTHi, decreased during the study period (p=0.004). Three hundred and eighty-seven children (63.0%) with AOM developed spontaneous otorrhea. Compared with patients who underwent tympanocentesis, those with spontaneous otorrhea were younger (27.0±16.4 vs. 31.1±15.2 months of age, p=0.004), more likely to have a previous history of AOM (p=0.019), and more likely to receive more antibiotics (p=0.012). The third most common pathogen was S. pyogenes (25 patients [4.1%]). S. pyogenes occurred more often in children > 5 years of age and was associated with spontaneous otorrhea (p<0.001). S. pneumoniae and NTHi are common causes of culture-confirmed AOM in Taiwanese children. Although S. pyogenes is not as common, it usually causes AOM in children > 5 years of age and is associated with spontaneous otorrhea. Copyright © 2012. Published by Elsevier B.V.

The role of algal organic matter in the separation of algae and cyanobacteria using the novel "Posi" - Dissolved air flotation process.

PubMed

Hanumanth Rao, Narasinga Rao; Yap, Russell; Whittaker, Michael; Stuetz, Richard M; Jefferson, Bruce; Peirson, William L; Granville, Anthony M; Henderson, Rita K

2018-03-01

Algae and cyanobacteria frequently require separation from liquid media in both water treatment and algae culturing for biotechnology applications. The effectiveness of cell separation using a novel dissolved air flotation process that incorporates positively charged bubbles (PosiDAF) has recently been of interest but has been shown to be dependent on the algae or cyanobacteria species tested. Previously, it was hypothesised that algal organic matter (AOM) could be impacting the separation efficiency. Hence, this study investigates the influence of AOM on cell separation using PosiDAF, in which bubbles are modified using a commercially available cationic polyelectrolyte poly(N, N-diallyl-N,N-dimethylammonium chloride) (PDADMAC). The separation of Chlorella vulgaris CS-42/7, Mychonastes homosphaera CS-556/01 and two strains of Microcystis aeruginosa (CS-564/01 and CS-555/1), all of which have similar cell morphology but different AOM character, was investigated. By testing the cell separation in the presence and absence of AOM, it was determined that AOM enhanced cell separation for all the strains but to different extents depending on the quantity and composition of carbohydrates and proteins in the AOM. By extracting AOM from the strain for which optimal separation was observed and adding it to the others, cell separation improved from <55% to >90%. This was attributed to elevated levels of acidic carbohydrates as well as glycoprotein-carbohydrate conjugations, which in turn were related to the nature and quantity of proteins and carbohydrates present in the AOM. Therefore, it was concluded that process optimisation requires an in-depth understanding of the AOM and its components. If culturing algae for biotechnology applications, this indicates that strain selection is not only important with respect to high value product content, but also for cell separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

A randomized comparative study of levofloxacin versus amoxicillin/clavulanate for treatment of infants and young children with recurrent or persistent acute otitis media.

PubMed

Noel, Gary J; Blumer, Jeffrey L; Pichichero, Michael E; Hedrick, James A; Schwartz, Richard H; Balis, Dainius A; Melkote, Rama; Bagchi, Partha; Arguedas, Adriano

2008-06-01

The need for alternative antimicrobial therapy for recurrent and persistent acute otitis media (AOM) in children has raised interest in assessing the efficacy and safety of fluoroquinolones for treatment of these infections. In an evaluator-blinded, active-comparator, noninferiority, multicenter study, children (6 months to <5 years) were randomized 1:1 to receive levofloxacin (10 mg/kg twice daily) or amoxicillin/clavulanate (14:1; amoxicillin 45 mg/kg twice daily) for 10 days, with evaluations 4-6 days of therapy (visit 2), 2-5 days after completing therapy (visit 3), and 10-17 days after last dose (visit 4). Primary outcome was clinical cure at visit 3 based on resolution of clinical signs and symptoms of AOM. A total of 1650 children were randomized and 1305 were clinically evaluable at visit 3 (630 levofloxacin, 675 comparator). Clinical cure rates were 72.4% (456 of 630) in levofloxacin-treated and 69.9% (472 of 675) in amoxicillin/clavulanate-treated children. Cure rates were also similar for levofloxacin and comparator for each age group (< or =24 months: 68.9% versus 66.2%; >24 months: 76.9% versus 75.1%; respectively). Cure rates at visit 4 were 74.9% and 73.8% in levofloxacin and amoxicillin/clavulanate groups, respectively. The upper limits of the confidence intervals were less than the noninferiority margin of 10% indicating that levofloxacin treatment is noninferior to comparator treatment overall and in both infants (6 months to 2 years) and children 2-5 years. No differences between treatment groups regarding the frequency or type of adverse events were apparent. Levofloxacin was not inferior to amoxicillin/clavulanate for the treatment of recurrent and/or persistent AOM in infants and children.

Comparison of first year of life acute otitis media admissions before and after the 13-valent pneumococcal conjugate vaccine.

PubMed

Marom, Tal; Israel, Ofer; Gavriel, Haim; Pitaro, Jacob; Baker, Ali Abo; Eviatar, Ephraim

2017-06-01

Acute otitis media (AOM) is a common childhood infection, which is usually managed in the outpatient setting. Yet, the more severe cases are referred for inpatient treatment. We hypothesized that pneumococcal conjugate vaccines (PCVs), administered during the first year of life, would decrease AOM admissions rate in this age group. We studied the characteristics of infants admitted with AOM and acute mastoiditis (AM) in the PCV13 era, routinely given from November 2010 to all infants. Charts of infants ≤1 year that were hospitalized during 1/1/2010-31/12/2015 with AOM, with or without AM, were retrieved using hospitalization codes. We compared 2010-11 (transition years, from PCV7 to PCV13) to 2012-15 (post-PCV13 marketing years). AOM was the primary/secondary discharge diagnosis in ∼4% of all admitted infants ≤1 year. Boys had more admissions than girls (62% vs 38%). Accuracy of AOM diagnoses substantially increased in the post-marketing years. The average hospitalization duration slightly shortened, from 3.21 (2010-11) to 2.99 days (2012-15) (p = 0.52). Despite considerably modest pre-admission antibiotic treatment rate (<30%), AM was infrequent (∼3.4% of AOM admissions). Amoxicillin was the most common antibiotic therapy given before admission and during hospitalization. The number of myringotomies, usually reserved for treatment failure cases, significantly declined, and there were almost no cases of resistant bacteria. Respiratory syncytial virus was detected in ∼20% of collected respiratory samples, and influenza A/B viruses in ∼8%. AOM is still a major cause for hospitalization of infants in the PCV13 era. Yet, complications are infrequent, and AM rate is low. Copyright © 2017 Elsevier B.V. All rights reserved.

Reducing the frequency of acute otitis media by individualized care.

PubMed

Pichichero, Michael E; Casey, Janet R; Almudevar, Anthony

2013-05-01

We sought to determine if use of more stringent diagnostic criteria for acute otitis media (AOM) than currently advocated by the American Academy of Pediatrics, tympanocentesis and pathogen-specific antibiotic treatment (individualized care) would result in reducing the incidence of recurrent AOM and consequent tympanostomy tube surgery. A 5-year longitudinal, prospective study in Rochester, NY, was conducted from July 2006 to July 2011 involving 254 individualized care children. When this individualized care group developed symptoms of AOM, strict diagnostic criteria were applied and a tympanocentesis was performed. Pathogen resistance to empiric high-dose amoxicillin/clavulanate (80 mg/kg of amoxicillin component) caused a change in antibiotic to an optimized choice. Legacy controls (n = 208) were diagnosed with the same diagnostic criteria by the same physicians as the individualized care group and received the same empiric amoxicillin/clavulanate (80 mg/kg of amoxicillin component) but no tympanocentesis or change in antibiotic. Community control children (n = 1020) were diagnosed according to current American Academy of Pediatrics guidelines and treated with high-dose amoxicillin (80 mg/kg) without tympanocentesis as guideline recommended. 5.9% of children of the individualized care group compared with 14.4% of Legacy controls and 27.3% of community controls became otitis prone, defined as 3 episodes of AOM within a 6-month time span or 4 AOM episodes within a 12-month time span (P < 0.0001). 2.4% of the individualized care group compared with 6.3% of Legacy controls, and 14.8% of community controls received tympanostomy tubes (P < 0.0001). Individualized care of AOM significantly reduces the frequency of AOM and tympanostomy tube surgery. Use of strict diagnostic criteria for AOM and empiric antibiotic treatment using evidence-based knowledge of circulating otopathogens and their antimicrobial susceptibility profile also produces improved outcomes.

Influenza vaccines for preventing acute otitis media in infants and children.

PubMed

Norhayati, Mohd N; Ho, Jacqueline J; Azman, Mohd Y

2015-03-24

Acute otitis media (AOM) is one of the most common infectious diseases in children. It has been reported that 64% of infants have an episode of AOM by the age of six months and 86% by one year. Although most cases of AOM are due to bacterial infection, it is commonly triggered by a viral infection. In most children it is self limiting, but it does carry a risk of complications. Since antibiotic treatment increases the risk of antibiotic resistance, influenza vaccines might be an effective way of reducing this risk by preventing the development of AOM. To assess the effectiveness of influenza vaccine in reducing the occurrence of acute otitis media (AOM) in infants and children. We searched CENTRAL (2014, Issue 6), MEDLINE (1946 to July week 1, 2014), EMBASE (2010 to July 2014), CINAHL (1981 to July 2014), LILACS (1982 to July 2014), Web of Science (1955 to July 2014) and reference lists of articles to July 2014. Randomised controlled trials (RCTs) comparing influenza vaccine with placebo or no treatment in infants and children aged younger than six years old. We included children of either sex and of any ethnicity, with or without a history of recurrent AOM. Two review authors independently screened studies, assessed trial quality and extracted data. We performed statistical analyses using the random-effects and fixed-effect models and expressed the results as risk ratio (RR), risk difference (RD) and number needed to treat to benefit (NNTB) for dichotomous outcomes, with 95% confidence intervals (CI). We included 10 trials (six trials in high-income countries and four multicentre trials in high-, middle- and low-income countries) involving 16,707 children aged six months to six years. Eight trials recruited participants from a healthcare setting. Nine trials (and all five trials that contributed to the primary outcome) declared funding from vaccine manufacturers. Four trials reported adequate allocation concealment and nine trials reported adequate blinding of participants and personnel. Attrition was low for all trials included in the analysis.The primary outcome showed a small reduction in at least one episode of AOM over at least six months of follow-up (five trials, 4736 participants: RR 0.80, 95% CI 0.67 to 0.96; RD -0.04, 95% CI -0.07 to -0.02; NNTB 25, 95% CI 15 to 50).The subgroup analyses (i.e. number of courses, settings, seasons or types of vaccine administered) showed no differences.There was a reduction in the use of antibiotics in vaccinated children (two trials, 1223 participants: RR 0.70, 95% CI 0.59 to 0.83; RD -0.15, 95% CI -0.30 to -0.00).There was no significant difference in the utilisation of health care for the one trial that provided sufficient information to be included. The use of influenza vaccine resulted in a significant increase in fever (six trials, 10,199 participants: RR 1.15, 95% CI 1.06 to 1.24; RD 0.02, 95% CI -0.00 to 0.05) and rhinorrhoea (six trials, 10,563 children: RR 1.17, 95% CI 1.07 to 1.29; RD 0.09, 95% CI 0.01 to 0.16) but no difference in pharyngitis. No major adverse events were reported.Compared to the protocol, the review included a subgroup analysis of AOM episodes by season, and changed the types of influenza vaccine from a secondary outcome to a subgroup analysis. Influenza vaccine results in a small reduction in AOM. The observed reduction with the use of antibiotics needs to be considered in the light of current recommended practices aimed at avoiding antibiotic overuse. Safety data from these trials are limited. The benefits may not justify the use of influenza vaccine without taking into account the vaccine efficacy in reducing influenza and safety data. The quality of the evidence was high to moderate. Additional research is needed.

Is soy intake related to age at onset of menarche? A cross-sectional study among adolescents with a wide range of soy food consumption

PubMed Central

2014-01-01

Background Early onset of menarche may negatively influence the future health of adolescent girls. Several factors affect the timing of menarche but it is not clear if soy foods consumption around pubertal years plays a role; thus, we examined its relation to age at onset of menarche (AOM) in a high soy-consuming population. Methods We conducted a cross-sectional study on 339 girls ages 12–18 years attending middle and high schools near two Seventh-day Adventist universities in California and Michigan using a web-based dietary questionnaire and physical development tool. Soy consumption (categorized as total soy, meat alternatives, tofu/traditional soy, and soy beverages) was estimated from the questionnaire, while AOM was self-reported. Data analyses included descriptive statistics, Cox proportional hazards ratios, Kaplan-Meier curves and Poisson regression with adjustment for relevant confounders. Results Mean (SD) intakes were: total soy,12.9 (14.4) servings/week; meat alternatives, 7.0 (8.9) servings/week; tofu/traditional soy foods, 2.1 (3.8) servings/week; soy beverages, 3.8 (6.3) servings/week. Mean AOM was 12.5 (1.4) y for those who reached menarche. Consumption of total soy and the 3 types of soy foods was not significantly associated with AOM and with the odds for early- or late-AOM. Adjustment for demographic and dietary factors did not change the results. Conclusion Soy intake is not associated with AOM in a population of adolescent girls who have a wide range of, and relatively higher, soy intake than the general US population. Our finding suggests that the increasing popularity of soy in the US may not be associated with AOM. PMID:24889551

Is soy intake related to age at onset of menarche? A cross-sectional study among adolescents with a wide range of soy food consumption.

PubMed

Segovia-Siapco, Gina; Pribis, Peter; Messina, Mark; Oda, Keiji; Sabaté, Joan

2014-06-03

Early onset of menarche may negatively influence the future health of adolescent girls. Several factors affect the timing of menarche but it is not clear if soy foods consumption around pubertal years plays a role; thus, we examined its relation to age at onset of menarche (AOM) in a high soy-consuming population. We conducted a cross-sectional study on 339 girls ages 12-18 years attending middle and high schools near two Seventh-day Adventist universities in California and Michigan using a web-based dietary questionnaire and physical development tool. Soy consumption (categorized as total soy, meat alternatives, tofu/traditional soy, and soy beverages) was estimated from the questionnaire, while AOM was self-reported. Data analyses included descriptive statistics, Cox proportional hazards ratios, Kaplan-Meier curves and Poisson regression with adjustment for relevant confounders. Mean (SD) intakes were: total soy,12.9 (14.4) servings/week; meat alternatives, 7.0 (8.9) servings/week; tofu/traditional soy foods, 2.1 (3.8) servings/week; soy beverages, 3.8 (6.3) servings/week. Mean AOM was 12.5 (1.4) y for those who reached menarche. Consumption of total soy and the 3 types of soy foods was not significantly associated with AOM and with the odds for early- or late-AOM. Adjustment for demographic and dietary factors did not change the results. Soy intake is not associated with AOM in a population of adolescent girls who have a wide range of, and relatively higher, soy intake than the general US population. Our finding suggests that the increasing popularity of soy in the US may not be associated with AOM.

More Protection of Lactobacillus acidophilus Than Bifidobacterium bifidum Probiotics on Azoxymethane-Induced Mouse Colon Cancer.

PubMed

Agah, Shahram; Alizadeh, Ali Mohammad; Mosavi, Maryam; Ranji, Peyman; Khavari-Daneshvar, Hossein; Ghasemian, Farnaz; Bahmani, Sahar; Tavassoli, Abbas

2018-04-22

Based on the ability of the probiotics in the gut microflora modification, they can have the beneficial effects on diseases in the short and/or the long term. In previous study, we revealed that unlike Bifidobacterium bifidum, the amount of Lactobacillus acidophilus remained almost unchanged in mice gut microflora in the long term, indicating more stability of L. acidophilus than B. bifidum which can be used to prevent some incurable diseases such as cancer. Thirty-eight male BALB/c mice were divided into four groups, control, azoxymethane (AOM), L. acidophilus, and B. bifidum probiotics, to evaluate the protective effects of the probiotics on AOM-induced mouse colon cancer. Except for the control group, the rest of the animals were weekly given AOM (15 mg/kg, s.c) in three consecutive weeks. Colon lesion incidence was 74% in the AOM group in comparison with the control (0%) (P < 0.05). The lesions were varied from mild to severe dysplasia and colonic adenocarcinoma. Administration of the probiotics inhibited the incidence of colonic lesions by about 57% in L. acidophilus (P < 0.05) and 27% in B. bifidum (P > 0.05) compared to the AOM group. The serum levels of CEA and CA19-9 tumor markers were significantly decreased in L. acidophilus in comparison with the AOM group (P < 0.05). Moreover, the serum levels of IFN-γ and IL-10 and the number of CD4 + and CD8 + cells were significantly increased in L. acidophilus compared to AOM (P < 0.05). Our study highlighted the more potential effects of L. acidophilus probiotic than B. bifidum on mouse colon cancer.

Chemopreventive effects of Ku-jin tea against AOM-induced precancerous colorectal lesions in rats and metabolomic analysis.

PubMed

Bi, Wu; Liu, Haibo; Shen, Jie; Zhang, Ling-Hua; Li, Pei; Peng, Bing; Cao, Li; Zhang, Pengfei; He, Chunnian; Xiao, Peigen

2017-11-21

Ku-jin tea (KJT) is a health beverage prepared from the leaves of the plant Acer tataricum subsp. ginnala that has been consumed in some regions of China for thousands of years. KJT contains high levels of anti-inflammatory and antioxidative compounds such as ginnalins, but little is known about the chemopreventive effect of KJT on colon cancer. In this study, we investigated the preventive effects of KJT on colon carcinogenesis using the azoxymethane (AOM)-induced precancerous colorectal lesion model in rats. The results showed that the number of aberrant crypts, aberrant crypt foci (ACF) and crypts/focus in rats of the KJT + AOM group were significantly decreased compared with rats of the AOM group (p < 0.01). Further exploration of the prevention mechanism of KJT by UPLC-QTOF/MS-based urinary metabolomics showed that 5 metabolic pathways were modulated, including purine metabolism and amino acid metabolism, in the group with KJT. In addition, the levels of the immunomodulatory cytokines IL-1α and IL-10 were significantly decreased, and the levels of IL-2 in the serum of AOM rats increased after KJT treatment. Our present data suggest that KJT can inhibit AOM-induced colonic ACF formation and might be a useful chemopreventive agent against colorectal carcinogenesis.

Non-typeable Haemophilus influenzae and Streptococcus pneumoniae as primary causes of acute otitis media in colombian children: a prospective study

PubMed Central

2011-01-01

Background Acute otitis media (AOM) is one of the most frequently encountered bacterial infections in children aged < 5 years; Streptococcus pneumoniae (S. pneumoniae) and non-typeable Haemophilus influenzae (NTHi) are historically identified as primary AOM causes. Nevertheless, recent data on bacterial pathogens causing AOM in Latin America are limited. This prospective study aimed to identify and characterize bacterial etiology and serotypes of AOM cases including antimicrobial susceptibility in < 5 year old Colombian children. Methods From February 2008 to January 2009, children ≥3 months and < 5 years of age presenting with AOM and for whom a middle ear fluid (MEF) sample was available were enrolled in two medical centers in Cali, Colombia. MEF samples were collected either by tympanocentesis procedure or spontaneous otorrhea swab sampling. Bacteria were identified using standard laboratory methods, and antimicrobial resistance testing was performed based on the 2009 Clinical and Laboratory Standards Institute (CLSI) criteria. Most of the cases included in the study were sporadic in nature. Results Of the 106 enrolled children, 99 were included in the analysis. Bacteria were cultured from 62/99 (63%) of samples with S. pneumoniae, H. influenzae, or S. pyogenes. The most commonly isolated bacteria were H. influenzae in 31/99 (31%) and S. pneumoniae in 30/99 (30%) of samples. The majority of H. influenzae episodes were NTHi (27/31; 87%). 19F was the most frequently isolated pneumococcal serotype (10/30; 33%). Of the 30 S. pneumoniae positive samples, 8/30 (27%) were resistant to tetracycline, 5/30 (17%) to erythromycin and 8/30 (27%) had intermediate resistance to penicillin. All H. influenzae isolates tested were negative to beta-lactamase. Conclusions NTHi and S. pneumoniae are the leading causes of AOM in Colombian children. A pneumococcal conjugate vaccine that prevents both pathogens could be useful in maximizing protection against AOM. PMID:21208431

Impact of Pediatric Acute Otitis Media on Child and Parental Quality of Life and Associated Productivity Loss in Malaysia: A Prospective Observational Study.

PubMed

Crawford, Bruce; Hashim, Siti Sabzah Mohd; Prepageran, Narayanan; See, Goh Bee; Meier, Genevieve; Wada, Keiko; Coon, Cheryl; Delgleize, Emmanuelle; DeRosa, Michael

2017-03-01

Acute otitis media (AOM) affects both child and parental quality of life (QoL). Data on QoL associated with AOM in Malaysia is sparse, and the burden of indirect costs have not been previously reported. To determine the effect of pediatric AOM on child and parental QoL in Malaysia and its economic impact (indirect costs). We utilized a set of QoL questionnaires (PAR-AOM-QOL, OM-6, and EQ-5D) combined with questions addressing work/productivity loss and financial costs associated with caring for a child during his or her illness in an observational, multicenter, prospective study. One hundred and ten AOM patients aged ≤5 years were included in the analysis. The majority of respondents were the patient's mother. Parental QoL was negatively affected for both emotional and daily disturbance scales, but the level of disturbance was low. Using OM-6, the greatest negative impact was on the child's QoL, followed by caregiver concerns, physical suffering, and emotional distress. Using EQ-5D, a moderately positive relationship between parents' emotional disturbance and daily disturbance, and a weak, negative correlation between parental emotional disturbance and parental health status was found. Parents with paid employment took an average of 21 h from work to care for their child, at an average cost of 321.8 Malaysian ringgit (US$97) in addition to their contribution to direct medical costs. Productivity losses whilst at work, uncompensated wage losses, and leisure time losses are also reported. This study found that AOM is associated with some negative impact on parental QoL and significant economic impact at both patient and societal levels. The findings provide useful data on healthcare resource utilization and disease burden of AOM in Malaysia.

Anaerobic methane oxidation may be more prevalent in surface soils than was originally thought

NASA Astrophysics Data System (ADS)

Gauthier, Mathieu; Bradley, Robert L.; Šimek, Miloslav

2013-04-01

Anaerobic oxidation of methane (CH4) (AOM) is a process that was first reported to occur in deep anoxic marine sediments. In this environment, CH4 is oxidized with sulphate (SO42-) as the terminal electron acceptor. It is mediated by a syntrophic consortium formed by SO42- reducing bacteria and anaerobic CH4 oxidizing Archaea, or by the latter alone. Since this landmark discovery, AOM was found to occur in other environments including freshwater lake sediments and water columns, mud volcanoes, landfill leachate, deep buried Holocene sediments and hydrocarbon contaminated aquifers. All of these situations are very specific and point to AOM as being primarily occurring in highly reducing conditions. Thus, observations of AOM in surface soils with fluctuating REDOX conditions are relatively scarce, although a few independent studies have reported AOM in surface peatlands as well as in a forest soil. Furthermore, AOM may follow different pathways, such as via the coupled oxidation of CH4 and reduction of manganese (Mn(IV)) or iron (Fe(III)), or by a lone denitrifying species that converts nitrite to nitric oxide in order to generate O2 that is then used internally to oxidize CH4. Thus, the goal of our study was to determine whether AOM is more prevalent than was thought in hydromorphic surface soils across different environments, and whether the addition of NO3- or SO4= as alternative electron acceptors may stimulate the process. We collected samples from 3 peatland soils in Scotland, 2 acid-sulphate soils in Finland, and shore sediments of 15 drained fish ponds in the Czech Republic. Subsamples were incubated in the absence of O2 and amended with either NO3-, SO42-, or left unamended (control). The net flux of CH4 and CO2 were assessed by gas chromatography after 2, 20, 40 and 60 days. We also used a 13C-CH4 isotope dilution technique to determine gross production and consumption rates of CH4. We detected AOM in all of our soils, with oxidation rates ranging between 0.001 and 37.28 nmol g-1 day-1, suggesting that AOM may be more ubiquitous than was originally thought. On the other hand, no clear patterns emerged as to the effects of NO3- or SO42- amendments on this process.

Evidence on Anaerobic Methane Oxidation (AOM) in a boreal cultivated peatland with natural and added electron acceptors

NASA Astrophysics Data System (ADS)

Dorodnikov, Maxim; Silvennoinen, Hanna; Martikainen, Pertti; Dörsch, Peter

2015-04-01

Anaerobic oxidation of methane (AOM) is a process of methane (CH4) consumption under anoxic conditions driven by microorganisms, which oxidize CH4 with various alternate electron acceptors (AEA): sulfate, nitrate, nitrite, metals-(Fe, Mn, Cu), organic compounds. AOM is common in marine ecosystems, where microbial sulfate reduction (SR) consumes most of the CH4 produced in sediments. Despite the global significance of AOM, the exact mechanisms and relevance of the process in terrestrial ecosystems are almost unknown. In the current study the occurrence of AOM was tested for two organic soil horizons (30 and 40 cm depth) and one mineral sub-soil (sand, 50 cm depth) of a cultivated boreal peatland (Linnansuo, Eastern Finland, energy crop Phalaris arundinacea - reed canarygrass) under controlled conditions with the addition of 13C-labeled CH4 and two common AEAs - SO4-2 and Fe+3. Concentrations of CH4, CO2 and O2 were continuously measured during 10 days of incubation and CO2 was sampled periodically under anaerobic conditions for stable 13C analysis. Oxygen dynamics revealed negligible O2 contamination during incubation and its trace amounts (0.05-0.8% from the atmospheric) were accounted in the net CH4 uptake. Application of 13C-enriched CH4 (4.9 atom%) allowed to track the label in CO2 as the end-product of AOM. The highest 13CO2 enrichment (up to 60‰) was observed in mineral sub-soil, however AOM was quantitatively more pronounced in the upper 30 cm horizon (2.1 vs. 0.2 μg CO2 g soil DW-1 in the 50 cm sub-soil). The highest AOM rate of 8.9 ng CO2 g soil DW-1 h-1 was estimated for the control treatment where no AEAs were added indicating sufficient amount of naturally available AEAs, likely organic compounds. This rate was 50 times more intensive (on the C basis) than the CH4 production potential of the same soil. In contrast, external AEAs decreased AOM rates but added Fe+3 stimulated decomposition of native SOM (as seen from the most depleted 13CO2 signatures). Thus, the experiments revealed that this organic soil had capacity for AOM with its natural electron acceptors. Further AOM assessments may change the existing concept of carbon/CH4 cycling in terrestrial ecosystems and will improve current process-based models of regional and global carbon balance.

Acute otitis media.

PubMed

Dickson, Gretchen

2014-03-01

One in 4 children will have at least 1 episode of acute otitis media (AOM) by age 10 years. AOM results from infection of fluid that has become trapped in the middle ear. The bacteria that most often cause AOM are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Differentiating AOM from otitis media with effusion (OME) is a critical skill for physicians, as accurate diagnosis will guide appropriate treatment of these conditions. Although fluid is present in the middle ear in both conditions, the fluid is not infected in OME as is seen in AOM patients. Copyright © 2014 Elsevier Inc. All rights reserved.

The AOM/DSS murine model for the study of colon carcinogenesis: From pathways to diagnosis and therapy studies

PubMed Central

Robertis, Mariangela De; Massi, Emanuela; Poeta, Maria Luana; Carotti, Simone; Morini, Sergio; Cecchetelli, Loredana; Signori, Emanuela; Fazio, Vito Michele

2011-01-01

Colorectal cancer (CRC) is a major health problem in industrialized countries. Although inflammation-linked carcinogenesis is a well accepted concept and is often observed within the gastrointestinal tract, the underlying mechanisms remain to be elucidated. Inflammation can indeed provide initiating and promoting stimuli and mediators, generating a tumour-prone microenvironment. Many murine models of sporadic and inflammation-related colon carcinogenesis have been developed in the last decade, including chemically induced CRC models, genetically engineered mouse models, and xenoplants. Among the chemically induced CRC models, the combination of a single hit of azoxymethane (AOM) with 1 week exposure to the inflammatory agent dextran sodium sulphate (DSS) in rodents has proven to dramatically shorten the latency time for induction of CRC and to rapidly recapitulate the aberrant crypt foci–adenoma–carcinoma sequence that occurs in human CRC. Because of its high reproducibility and potency, as well as the simple and affordable mode of application, the AOM/DSS has become an outstanding model for studying colon carcinogenesis and a powerful platform for chemopreventive intervention studies. In this article we highlight the histopathological and molecular features and describe the principal genetic and epigenetic alterations and inflammatory pathways involved in carcinogenesis in AOM/DSS–treated mice; we also present a general overview of recent experimental applications and preclinical testing of novel therapeutics in the AOM/DSS model. PMID:21483655

Oleuropein Prevents Azoxymethane-Induced Colon Crypt Dysplasia and Leukocytes DNA Damage in A/J Mice.

PubMed

Sepporta, Maria Vittoria; Fuccelli, Raffaela; Rosignoli, Patrizia; Ricci, Giovanni; Servili, Maurizio; Fabiani, Roberto

2016-08-19

Previous studies have shown that the precursor of olive oil secoiridoids, Oleuropein (OL) has several in vitro chemopreventive properties. OL inhibits proliferation and induces apoptosis in breast, thyroid, prostate, and colorectal cancer (CRC) cells. Much less is known about the effects of OL on animal models of carcinogenesis. In this study, we investigated the ability of OL to prevent the azoxymethane (AOM)-induced colon cancer upset and DNA damage in mice. Animals, fed with a basal diet either enriched or not with OL (125 mg/kg), were injected with AOM (10 mg/kg, once a week for 6 weeks) and sacrificed after either 7 weeks for histological analysis of colon crypt dysplasia and evaluation of DNA damage in leukocytes or 17 weeks for counting the macroscopically observable colon tumors. An OL-enriched diet prevented the AOM-induced preneoplastic lesions in different colon segments, reducing the severity of crypt dysplasia and DNA damage in peripheral leukocytes. In addition, OL significantly reduced the AOM-induced tumor incidence from 57% to 14% (P < .05, chi-square test) in the medial colon segment. This study shows that OL is able to prevent CRC and DNA damage in mice treated with the carcinogen AOM. These results stimulate further human cancer prevention studies with OL-enriched food supplements that are actually available on the market.

Attitudes and interests toward research among students at two colleges of acupuncture and Oriental medicine

PubMed Central

Wayne, PM; Hammerschlag, R; German, JS; Chapman, T

2010-01-01

Background Collaborative input from clinicians of acupuncture and Oriental medicine (AOM) is required for sound AOM research, and AOM training institutions have begun to include research education into their curriculum. However, few attempts have been made to systematically evaluate AOM practitioners’ perspectives on the value of research to their profession. Methods We conducted surveys of AOM students at two institutions that have begun to integrate research training into their curriculum, the New England School of Acupuncture and the Oregon College of Oriental Medicine. Surveys were conducted to assess current attitudes regarding the value of research, and to serve as a reference point for documenting the impact of ongoing research training programs on these attitudes. Surveys at both institutions were independently developed and administered, but shared 7 questions that were phrased very similarly. This paper summarizes responses to these questions. Results Surveys at both institutions suggest interest in research among AOM students is high in first year students; students in later years showed a lower level of interest, but the cross-sectional design of this survey does not allow any temporal effects to be inferred. Results also indicate that AOM students believe research is highly relevant to how both the public and the health insurance industry view their system of health care, but not highly relevant to their own clinical practice of AOM. The belief that research is of limited relevance to clinical practice was associated with widespread belief that scientific methods may not be consistent with the principles of AOM. Conclusions Results of these surveys provide important preliminary information about AOM students attitudes towards research, and thus the value and future specific needs of research training programs targeting this population. Repeated implementation of validated versions of our surveys are needed to confirm the trends we report and to evaluate the impact of research training programs already in place on AOM students attitudes towards research. PMID:20129309

Parental experiences and attitudes regarding the management of acute otitis media--a comparative questionnaire between Finland and The Netherlands.

PubMed

Tähtinen, Paula A; Boonacker, Chantal W B; Rovers, Maroeska M; Schilder, Anne G M; Huovinen, Pentti; Liuksila, Pirjo-Riitta; Ruuskanen, Olli; Ruohola, Aino

2009-12-01

Both treatment guidelines and the amount of antibiotics used for acute otitis media (AOM) vary across western countries. Parental expectations and their awareness of antimicrobial use and resistance, which may also be influenced by the guidelines, are not yet completely known. To compare parental experiences and opinions regarding the management of AOM in children with AOM in Finland and The Netherlands. We sent the questionnaires via public day care in Turku, Finland, and Utrecht, The Netherlands. We asked about family background, child's history of AOM and parental experiences and attitudes about AOM treatment and antimicrobial resistance. Of 1151 participants, 83% in Finland and 49% in The Netherlands had had at least one episode of AOM. Antibiotics were used more frequently in Finland than in The Netherlands, 99% versus 78%, respectively. More Finnish parents reported to believe that antibiotics are necessary in the treatment of AOM as compared to Dutch parents. Use of analgesics for AOM was similar (80% in Finland and 86% in The Netherlands). One-third of the parents had discussed resistance with their doctor. According to parental experiences, antimicrobial resistance had caused more problems in Finland than in The Netherlands (20% versus 2%). Finally, 88% of parents in Finland and 65% in The Netherlands were worried that bacteria could become resistant to antibiotics. Treatment practices and parental expectations seem to interact with each other. Therefore, if we aim to change AOM treatment practices, we have to modify both guidelines and parental expectations.

Azoxymethane protects intestinal stem cells and reduces crypt epithelial mitosis through a COX-1-dependent mechanism.

PubMed

Riehl, Terrence E; George, Robert J; Sturmoski, Mark A; May, Randal; Dieckgraefe, Brian; Anant, Shrikant; Houchen, Courtney W

2006-12-01

Azoxymethane (AOM) is a potent DNA-damaging agent and carcinogen that induces intestinal and colonic tumors in rodents. Evaluation of the stem cell population by colony formation assay reveals that, within 8 h after treatment, AOM (10 mg/kg) elicited a prosurvival response. In wild-type (WT) mice, AOM treatment induced a 2.5-fold increase in intestinal crypt stem cell survival. AOM treatment increased stem cell survival in cyclooxygenase (COX)-2(-/-) but not COX-1(-/-) mice, confirming a role of COX-1 in the AOM-induced increase in stem cell survival. COX-1 mRNA and protein expression as well as COX-1-derived PGE(2) synthesis were increased 8 h after AOM treatment. Immunohistochemical staining of COX-1 demonstrated expression of the enzyme in the crypt epithelial cells, especially in the columnar epithelial cells between the Paneth cells adjacent to the stem cell zone. WT mice receiving AOM exhibited increased intestinal apoptosis and a simultaneous reduction in crypt mitotic figures within 8 h of injection. There were no significant differences in baseline or AOM-induced intestinal epithelial apoptosis between WT and COX-1(-/-) mice, but there was a complete reversal of the AOM-mediated reduction in mitosis in COX-1(-/-) mice. This suggests that COX-1-derived PGE(2) may play a key role in the early phase of intestinal tumorigenesis in response to DNA damage and suggests that COX-1 may be a potential therapeutic target in this model of colon cancer.

Anaerobic oxidation of methane: an “active” microbial process

PubMed Central

Cui, Mengmeng; Ma, Anzhou; Qi, Hongyan; Zhuang, Xuliang; Zhuang, Guoqiang

2015-01-01

The anaerobic oxidation of methane (AOM) is an important sink of methane that plays a significant role in global warming. AOM was first found to be coupled with sulfate reduction and mediated by anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). ANME, often forming consortia with SRB, are phylogenetically related to methanogenic archaea. ANME-1 is even able to produce methane. Subsequently, it has been found that AOM can also be coupled with denitrification. The known microbes responsible for this process are Candidatus Methylomirabilis oxyfera (M. oxyfera) and Candidatus Methanoperedens nitroreducens (M. nitroreducens). Candidatus Methylomirabilis oxyfera belongs to the NC10 bacteria, can catalyze nitrite reduction through an “intra-aerobic” pathway, and may catalyze AOM through an aerobic methane oxidation pathway. However, M. nitroreducens, which is affiliated with ANME-2d archaea, may be able to catalyze AOM through the reverse methanogenesis pathway. Moreover, manganese (Mn4+) and iron (Fe3+) can also be used as electron acceptors of AOM. This review summarizes the mechanisms and associated microbes of AOM. It also discusses recent progress in some unclear key issues about AOM, including ANME-1 in hypersaline environments, the effect of oxygen on M. oxyfera, and the relationship of M. nitroreducens with ANME. PMID:25530008

Serum Antibody Response to Five Streptococcus pneumoniae Proteins during Acute Otitis Media in Otitis Prone and Non-Otitis Prone Children

PubMed Central

Kaur, Ravinder; Casey, Janet R.; Pichichero, Michael E.

2011-01-01

Background Streptococcus pneumoniae (Spn) is one of the common bacteria responsible for episodic acute otitis media (AOM; non-otitis prone), recurrent AOM (otitis-prone) and AOM treatment failure (AOMTF) in children. Objective From a population of 268 children we sought to compare the serum IgG antibody titers to five different Spn proteins (PhtD, LytB, PcpA, PhtE and Ply) that are vaccine candidates in children with episodic AOM (n=34), who were otitis prone (n=35), and who had AOMTF (n=25) caused by Spn. Methods Antibody was quantitated by ELISA. Results At their acute AOM visit, anti-PhtD, -LytB, -PhtE and −Ply IgG antibody titers in otitis-prone children were significantly lower compared to non-otitis prone children (p <0.05) and children with AOMTF (p <0.05). Comparing acute to convalescent titers of antibody after AOM we found that otitis-prone, AOMTF and non-otitis prone children had no significant change in geometric mean IgG antibody titers against the five proteins (except for PhtE in children with AOMTF), but detailed analysis showed that about one-third of the children in each cohort had a 2-fold rise in antibody to the studied antigens. While non-otitis prone children had significant increases (p <0.001) between 6 and 24 months of age in anti-PhtD, PcpA, PhtE and Ply IgG antibody titers as a consequence of nasopharyngeal colonization and AOM, otitis-prone children either failed to show rises or the rises were significantly less than the non-otitis prone children. Conclusion Otitis-prone and AOMTF children mount less of an IgG serum antibody response than non-otitis prone children to Spn proteins following AOM and nasopharyngeal colonization. PMID:21487325

Contemporary concepts in management of acute otitis media in children.

PubMed

Rettig, Eleni; Tunkel, David E

2014-10-01

Acute otitis media (AOM) is a common disease of childhood. AOM is most appropriately diagnosed by careful otoscopy with an understanding of clinical signs and symptoms. The distinction between AOM and chronic otitis media with effusion should be emphasized. Treatment should include pain management, and initial antibiotic treatment should be given to those most likely to benefit, including young children, children with severe symptoms, and those with otorrhea and/or bilateral AOM. Tympanostomy tube placement may be helpful for those who experience frequent episodes of AOM or fail medical therapy. Recent practice guidelines may assist the clinician with such decisions. Copyright © 2014 Elsevier Inc. All rights reserved.

Characteristics associated with anti-osteoporosis medication use: data from the Global Longitudinal Study of Osteoporosis in Women (GLOW) USA cohort

PubMed Central

Guggina, Pamela; Flahive, Julie; Hooven, Frederick H.; Watts, Nelson B.; Siris, Ethel S.; Silverman, Stuart; Roux, Christian; Pfeilschifter, Johannes; Greenspan, Susan L.; Díez-Pérez, Adolfo; Cooper, Cyrus; Compston, Juliet E.; Chapurlat, Roland; Boonen, Steven; Adachi, Jonathan D.; Anderson, Frederick A.; Gehlbach, Stephen

2016-01-01

Introduction Many women at risk of fracture do not receive anti-osteoporosis medication (AOM), while others may be receiving unnecessary treatment. Purpose To examine the characteristics associated with AOM use among women at low and high risk of fracture. Methods The Global Longitudinal Study of Osteoporosis in Women (GLOW) is a prospective cohort study in which data were collected, via self-administered questionnaires, from 60,393 non-institutionalized women aged ≥55 years in 10 countries between October 1, 2006 and April 30, 2008. This is a cross-sectional analysis of baseline USA data, in which women were classified as having low fracture risk (<65 years; no FRAX risk factors) or high fracture risk (≥65 years; prior fracture or ≥2 other FRAX risk factors). Results Of 27,957 women, 3013 were at low risk of fracture and 3699 were at high risk. Only 35.7% of high-risk women reported AOM treatment, rising to 39.5% for those with self-reported osteopenia and 65.4% for those with self-reported osteoporosis. Conversely, 13.4% of low-risk women reported AOM, rising to 28.7% for osteopenia and 62.4% for osteoporosis. Characteristics associated with significantly higher AOM treatment rates among low-and high-risk women were: osteoporosis (odds ratios 75.3 and 18.1, respectively), osteopenia (17.9 and 6.3), concern about osteoporosis (2.0 and 1.8), higher perceived risk of fracture (2.3 and 1.6), and higher vitality score (1.7 and 1.6). Conclusion Use of AOM is frequently inconsistent with published guidelines in both high -and low-risk women. Characteristics other than FRAX fracture risk appear to influence this use, particularly the presence of self-reported osteoporosis. PMID:22964142

Treatment of acute otitis media - challenges in the era of antibiotic resistance.

PubMed

Dagan, R

2000-12-08

The last decade is characterized by the increase in antibiotic resistance among respiratory bacterial pathogens in the presence of only modest progress in the development of new antibacterial agents to overcome this resistance. A series of recent studies show clearly that the increased resistance among the main AOM pathogens (namely Streptococcus pneumoniae and Haemophilus influenzae) is associated with a dramatic decrease in bacteriologic response to antibiotic treatment, which in turn has an impact on clinical response. Thus, the individual patient is affected by the increasing antibiotic resistance. Moreover, the society as a whole is now also affected because the carriage and spread of antibiotic resistant AOM pathogens is remarkably impacted by antibiotic treatment. New studies show the remarkable ability of antibiotics to rapidly promote nasopharyngeal carriage and spread of antibiotic-resistant AOM pathogens. In these studies, the increase in carriage of antibiotic resistant S. pneumoniae is shown already after 3-4 days from initiation of antibiotic treatment and may last for weeks to months after treatment. Children carrying antibiotic-resistant organisms transmit those organisms to their family and to their day care centers and thus a vicious cycle is created in which increased antibiotic resistance with decreased response leads to increased antibiotic use, which in turn leads to further increase in resistance. New antibiotics are not likely to improve this situation. It is clear that the challenge in the next decade is to prevent AOM rather than to treat it. Efforts to prevent AOM include improved environmental factors, immunization with bacterial and viral vaccines and some creative measures such as prevention of colonization and attachment to epithelium of AOM pathogens. Whether these efforts will prove successful or, even if successful, will only modify the clinical and bacteriologic picture presenting new challenges, only time will tell.

Identification of bacteria causing acute otitis media using Raman microspectroscopy

NASA Astrophysics Data System (ADS)

Ayala, Oscar D.; Wakeman, Catherine A.; Skaar, Eric P.; Mahadevan-Jansen, Anita

2016-03-01

Otitis media (OM) is the leading cause of acute physician visits and prescription of antibiotics for children. Current standard techniques to diagnose acute otitis media (AOM) are limited by their ability to probe only changes in symptoms of the bacterial infection that cause AOM. Furthermore, they are not able to detect the presence of or identify bacteria causing AOM, which is important for diagnosis and proper antibiotic treatment. Our goal is to detect the presence of and identify the pathogens involved in causing AOM based on their biochemical profile using Raman spectroscopy (RS). An inVia confocal Raman microscope (Renishaw) at 785 nm was used to detect bacteria causing AOM in vitro. The three main bacteria that cause AOM, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae were cultured in chocolate agar and Mueller-Hinton agar to determine which agar type would minimize Raman signal from the growth agar. Preliminary results identified specific Raman spectral features characteristic of S. pneumoniae. RS has the potential to accurately diagnose AOM, which will help in identifying the antibiotic that will be most beneficial for the patient and ultimately decrease the course of infection.

Chemoprevention studies of the flavonoids quercetin and rutin in normal and azoxymethane-treated mouse colon.

PubMed

Yang, K; Lamprecht, S A; Liu, Y; Shinozaki, H; Fan, K; Leung, D; Newmark, H; Steele, V E; Kelloff, G J; Lipkin, M

2000-09-01

In this study we investigated the chemopreventive effects of quercetin and rutin when added to standard AIN-76A diet and fed to normal and azoxymethane (AOM)-treated mice. Early changes in colonic mucosa were analyzed, including colonic cell proliferation, apoptotic cell death, cyclin D(1) expression and focal areas of dysplasia (FAD). The findings show that the number of colonic epithelial cells per crypt column increased (P: < 0.01) in each normal mouse group fed the flavonoids; AOM administration increased colonic crypt cell proliferation and resulted in a marked rise of bromodeoxyuridine-labeled cells in the lower proliferative zone of the crypt. Both supplementary dietary quercetin and rutin increased the apoptotic index and caused a redistribution of apoptotic cells along the crypt axis in normal mice fed a standard AIN-76A diet. The number of apoptotic cells/column and apoptotic indices markedly increased (P: < 0.01) in the AOM-treated group compared with untreated animals; apoptotic cells expanded throughout the colonic crypts after flavonoid supplementation and AOM administration. Positive cyclin D(1) expression was detected in mice on diets supplemented either with quercetin (P: < 0.01) or rutin (P: < 0.05). AOM administration resulted in the formation of FAD. Both the number of mice exhibiting FAD and the total numer of FAD observed were significantly reduced (P: < 0.01) in AOM-treated animals fed flavonoids compared with mice maintained on the standard AIN-76A diet. Surprisingly, however, quercetin alone was able to induce FAD in 22% of normal mice fed the standard AIN-76A diet.

Etiology of acute otitis media and serotype distribution of Streptococcus pneumoniae and Haemophilus influenzae in Chilean children <5 years of age

PubMed Central

Rosenblut, Andres; Napolitano, Carla; Pereira, Angelica; Moreno, Camilo; Kolhe, Devayani; Lepetic, Alejandro; Ortega-Barria, Eduardo

2017-01-01

Abstract The impact of bacterial conjugate vaccines on acute otitis media (AOM) is affected by several factors including population characteristics, bacterial etiology and vaccine conjugation method, carrier, and coverage. This study estimated the baseline etiology, distribution, and antibiotic susceptibility of bacterial serotypes that causes AOM in children aged <5 years in a public setting in Santiago, Chile. Children aged ≥3 months and <5 years referred to the physician for treatment of AOM episodes (with an onset of symptoms <72 h) were enrolled between September 2009 and September 2010. Middle ear fluid (MEF) was collected by tympanocentesis or by otorrhea for identification and serotyping of bacteria. Antibacterial susceptibility was tested using E-test (etrack: 112671). Of 160 children (mean age 27.10 ± 15.83 months) with AOM episodes, 164 MEF samples (1 episode each from 156 children; 2 episodes each from 4 children) were collected. Nearly 30% of AOM episodes occurred in children aged 12 to 23 months. Streptococcus pneumoniae (41.7% [58/139]) and Haemophilus influenzae (40.3% [56/139]) were predominant among the cultures that showed bacterial growth (85% [139/164]). All Streptococcus pneumoniae positive episodes were serotyped, 19F (21%) and 14 (17%) were the predominant serotypes; all Haemophilus influenzae strains were nontypeable. Streptococcus pneumoniae were resistant to penicillin (5%) and erythromycin (33%); Haemophilus influenzae were resistant to ampicillin (14%) and cefuroxime and cefotaxime (2% each). AOM in Chilean children is predominantly caused by Streptococcus pneumoniae and nontypeable Haemophilus influenzae. Use of a broad spectrum vaccine against these pathogens might aid the reduction of AOM in Chile. PMID:28178138

[Bacterial etiology of acute otitis media in Spain in the post-pneumococcal conjugate vaccine era].

PubMed

Pumarola, Felix; Salamanca de la Cueva, Ignacio; Sistiaga-Hernando, Alessandra; García-Corbeira, Pilar; Moraga-Llop, Fernando A; Cardelús, Sara; McCoig, Cynthia; Gómez Martínez, Justo Ramón; Rosell Ferrer, Rosa; Iniesta Turpin, Jesús; Devadiga, Raghavendra

2016-11-01

Acute otitis media (AOM) is common in children aged <3 years. A pneumococcal conjugate vaccine (PCV) (PCV7; Prevenar, Pfizer/Wyeth, USA) has been available in Spain since 2001, which has a coverage rate of 50-60% in children aged <5 years. Children aged ≥3 to 36 months with AOM confirmed by an ear-nose-throat specialist were enrolled at seven centers in Spain (February 2009-May 2012) (GSK study identifier: 111425). Middle-ear-fluid samples were collected by tympanocentesis or spontaneous otorrhea and cultured for bacterial identification. Culture-negative samples were further analyzed using polymerase chain reaction (PCR). Of 125 confirmed AOM episodes in 124 children, 117 were analyzed (median age: 17 months (range: 3-35); eight AOM episodes were excluded from analyses. Overall, 69% (81/117) episodes were combined culture- and PCR-positive for ≥1 bacterial pathogen; 44% (52/117) and 39% (46/117) were positive for Haemophilus influenzae (Hi) and Streptococcus pneumoniae (Spn), respectively. 77 of 117 episodes were cultured for ≥1 bacteria, of which 63 were culture-positive; most commonly Spn (24/77; 31%) and Hi (32/77; 42%). PCR on culture-negative episodes identified 48% Hi- and 55% Spn-positive episodes. The most common Spn serotype was 19F (4/24; 17%) followed by 19A (3/24; 13%); all Hi-positive episodes were non-typeable (NTHi). 81/117 AOM episodes (69%) occurred in children who had received ≥1 pneumococcal vaccine dose. NTHi and Spn were the main etiological agents for AOM in Spain. Impact of pneumococcal vaccination on AOM requires further evaluation in Spain, after higher vaccination coverage rate is reached. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Methane related changes in prokaryotic activity along geochemical profiles in sediments of Lake Kinneret (Israel)

NASA Astrophysics Data System (ADS)

Bar Or, I.; Ben-Dov, E.; Kushmaro, A.; Eckert, W.; Sivan, O.

2014-06-01

Microbial methane oxidation process (methanotrophy) is the primary control on the emission of the greenhouse gas methane (CH4) to the atmosphere. In terrestrial environments, aerobic methanotrophic bacteria are mainly responsible for oxidizing the methane. In marine sediments the coupling of the anaerobic oxidation of methane (AOM) with sulfate reduction, often by a consortium of anaerobic methanotrophic archaea (ANME) and sulfate reducing bacteria, was found to consume almost all the upward diffusing methane. Recently, we showed geochemical evidence for AOM driven by iron reduction in Lake Kinneret (LK) (Israel) deep sediments and suggested that this process can be an important global methane sink. The goal of the present study was to link the geochemical gradients found in the porewater (chemical and isotope profiles) with possible changes in microbial community structure. Specifically, we examined the possible shift in the microbial community in the deep iron-driven AOM zone and its similarity to known sulfate driven AOM populations. Screening of archaeal 16S rRNA gene sequences revealed Thaumarchaeota and Euryarchaeota as the dominant phyla in the sediment. Thaumarchaeota, which belongs to the family of copper containing membrane-bound monooxgenases, increased with depth while Euryarchaeota decreased. This may indicate the involvement of Thaumarchaeota, which were discovered to be ammonia oxidizers but whose activity could also be linked to methane, in AOM in the deep sediment. ANMEs sequences were not found in the clone libraries, suggesting that iron-driven AOM is not through sulfate. Bacterial 16S rRNA sequences displayed shifts in community diversity with depth. Proteobacteria and Chloroflexi increased with depth, which could be connected with their different dissimilatory anaerobic processes. The observed changes in microbial community structure suggest possible direct and indirect mechanisms for iron-driven AOM in deep sediments.

Nuclear Magnetic Resonance-Based Metabolomics Approach to Evaluate the Prevention Effect of Camellia nitidissima Chi on Colitis-Associated Carcinogenesis

PubMed Central

Li, Ming-Hui; Du, Hong-Zhi; Kong, Gui-Ju; Liu, Li-Bao; Li, Xin-Xin; Lin, Sen-Sen; Jia, Ai-Qun; Yuan, Sheng-Tao; Sun, Li; Wang, Jun-Song

2017-01-01

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, occurring in the colon or rectum portion of large intestine. With marked antioxidant, anti-inflammation and anti-tumor activities, Camellia nitidissima Chi has been used as an effective treatment of cancer. The azoxymethane/dextran sodium sulfate (AOM/DSS) induced CRC mice model was established and the prevention effect of C. nitidissima Chi extracts on the evolving of CRC was evaluated by examination of neoplastic lesions, histopathological inspection, serum biochemistry analysis, combined with nuclear magnetic resonance (NMR)-based metabolomics and correlation network analysis. C. nitidissima Chi extracts could significantly inhibit AOM/DSS induced CRC, relieve the colonic pathology of inflammation and ameliorate the serum biochemistry, and could significantly reverse the disturbed metabolic profiling toward the normal state. Moreover, the butanol fraction showed a better efficacy than the water-soluble fraction of C. nitidissima Chi. Further development of C. nitidissima Chi extracts as a potent CRC inhibitor was warranted. PMID:28744216

Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

PubMed

Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

2017-07-01

We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Isolation and Characterization of Microbes Mediating Thermodynamically Favorable Coupling of Anaerobic Oxidation of Methane and Metal Reduction

NASA Astrophysics Data System (ADS)

Glass, J. B.; Reed, B. C.; Sarode, N. D.; Kretz, C. B.; Bray, M. S.; DiChristina, T. J.; Stewart, F. J.; Fowle, D. A.; Crowe, S.

2014-12-01

Methane is the third most reduced environmentally relevant electron donor for microbial metabolisms after organic carbon and hydrogen. In anoxic ecosystems, the major sink for methane is anaerobic oxidation of methane (AOM) mediated by syntrophic microbial consortia that couple AOM to reduction of an oxidized electron acceptor to yield free energy. In marine sediments, AOM is generally coupled to reduction of sulfate despite an extremely small amount of free energy yield because sulfate is the most abundant electron acceptor in seawater. While AOM coupled to Fe(III) and Mn(IV) reduction (Fe- and Mn-AOM) is 10-30x more thermodynamically favorable than sulfate-AOM, and geochemical data suggests that it occurs in diverse environments, the microorganisms mediating Fe- and Mn-AOM remain unknown. Lake Matano, Indonesia is an ideal ecosystem to enrich for Fe- and Mn-AOM microbes because its anoxic ferruginous deep waters and sediments contain abundant Fe(III), Mn(IV) and methane, and extremely low sulfate and nitrate. Our research aims to isolate and characterize the microbes mediating Fe- and Mn-AOM from three layers of Lake Matano sediments through serial enrichment cultures in minimal media lacking nitrate and sulfate. 16S rRNA amplicon sequencing of sediment inoculum revealed the presence of the Fe(III)-reducing bacterium Geobacter (5-10% total microbial community in shallow sediment and 35-60% in deeper sediment) as well as 1-2% Euryarchaeota implicated in methane cycling, including ANME-1 and 2d and Methanosarcinales. After 90 days of primary enrichment, all three sediment layers showed high levels of Fe(III) reduction (60-90 μM Fe(II) d-1) in the presence of methane compared to no methane and heat-killed controls. Treatments with added Fe(III) as goethite contained higher abundances of Geobacter than the inoculum (60-80% in all layers), suggesting that Geobacter may be mediating Fe(III) reduction in these enrichments. Quantification of AOM rates is underway, and will be used to estimate the plausibility of metal-AOM as a thermodynamically favorable methane sink in anoxic ecosystems of both the modern and ancient Earth.

Paracetamol (acetaminophen) or non-steroidal anti-inflammatory drugs, alone or combined, for pain relief in acute otitis media in children.

PubMed

Sjoukes, Alies; Venekamp, Roderick P; van de Pol, Alma C; Hay, Alastair D; Little, Paul; Schilder, Anne Gm; Damoiseaux, Roger Amj

2016-12-15

Acute otitis media (AOM) is one of the most common childhood infectious diseases and a significant reason for antibiotic prescriptions in children worldwide. Pain from middle ear infection and pressure behind the eardrum is the key symptom of AOM. Ear pain is central to children's and parents' experience of the illness. Because antibiotics provide only marginal benefits, analgesic treatment including paracetamol (acetaminophen) and non-steroidal anti-inflammatory drugs (NSAIDs) is regarded as the cornerstone of AOM management in children. Our primary objective was to assess the effectiveness of paracetamol (acetaminophen) or NSAIDs, alone or combined, compared with placebo or no treatment in relieving pain in children with AOM. Our secondary objective was to assess the effectiveness of NSAIDs compared with paracetamol in children with AOM. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Issue 7, July 2016; MEDLINE (Ovid, from 1946 to August 2016), Embase (from 1947 to August 2016), CINAHL (from 1981 to August 2016), LILACS (from 1982 to August 2016) and Web of Science (from 1955 to August 2016) for published trials. We screened reference lists of included studies and relevant systematic reviews for additional trials. We searched WHO ICTRP, ClinicalTrials.gov, and the Netherlands Trial Registry (NTR) for completed and ongoing trials (search date 19 August 2016). We included randomised controlled trials (RCTs) comparing the effectiveness of paracetamol or NSAIDs, alone or combined, for pain relief in children with AOM. We also included trials of paracetamol or NSAIDs, alone or combined, for children with fever or upper respiratory tract infections (URTIs) if we were able to extract subgroup data on pain relief in children with AOM either directly or after obtaining additional data from study authors. Two review authors independently assessed methodological quality of the included trials and extracted data. We used the GRADE approach to rate the overall quality of evidence for each outcome of interest. We included three RCTs (327 children) which were assessed at low to moderate risk of bias.One RCT included 219 children with AOM, and used a three-arm, parallel group, double-blind design to compare paracetamol versus ibuprofen versus placebo. All children also received antibiotics and those with fever > 39 °C could have received paracetamol (30 mg to 60 mg) additionally to the studied treatments.Another RCT involved 156 febrile children (26 of whom had AOM). The study design was a three-arm, parallel group, double-blind design and compared paracetamol versus ibuprofen versus ibuprofen plus paracetamol.The third RCT included 889 children with respiratory tract infections (82 of whom had AOM). This study applied a 3 x 2 x 2 factorial, open-label design and compared paracetamol versus ibuprofen versus ibuprofen plus paracetamol. Study participants were randomised to one of the three treatment groups as well as two dosing groups (regular versus as required) and two steam inhalation groups (steam versus no steam).Authors of two RCTs provided crude subgroup data on children with AOM. We used data from the remaining trial to inform comparison of paracetamol versus placebo (148 children) and ibuprofen versus placebo (146 children) assessments. Data from all included RCTs informed comparison of ibuprofen versus paracetamol (183 children); data from the two RCTs informed comparison of ibuprofen plus paracetamol versus paracetamol alone (71 children).We found evidence, albeit of low quality, that both paracetamol and ibuprofen as monotherapies were more effective than placebo in relieving pain at 48 hours (paracetamol versus placebo: proportion of children with pain 10% versus 25%, RR 0.38, 95% CI 0.17 to 0.85; number needed to treat to benefit (NNTB) 7; ibuprofen versus placebo: proportion of children with pain 7% versus 25%, RR 0.28, 95% CI 0.11 to 0.70; NNTB 6). Very low quality evidence suggested that adverse events did not significantly differ between children treated with either paracetamol, ibuprofen or placebo.We found insufficient evidence of a difference between ibuprofen and paracetamol in relieving ear pain at 24 hours (2 RCTs, 39 children; RR 0.83, 95% CI 0.59 to 1.18; very low quality evidence), 48 to 72 hours (3 RCTs, 183 children; RR 0.91, 95% CI 0.54 to 1.54; low quality evidence) and four to seven days (2 RCTs, 38 children; RR 0.74, 95% CI 0.17 to 3.23; very low quality evidence).Data on the effectiveness of ibuprofen plus paracetamol versus paracetamol alone came from two RCTs that provided crude subgroup data for 71 children with AOM. The small sample provided imprecise effect estimates and we were consequently unable to draw any firm conclusions (very low quality evidence). Despite explicit guideline recommendations on its use, current evidence on the effectiveness of paracetamol or NSAIDs, alone or combined, in relieving pain in children with AOM is limited. Low quality evidence indicates that both paracetamol and ibuprofen as monotherapies are more effective than placebo in relieving short-term ear pain in children with AOM. There is insufficient evidence of a difference between ibuprofen and paracetamol in relieving short-term ear pain in children with AOM, whereas data on the effectiveness of ibuprofen plus paracetamol versus paracetamol alone were insufficient to draw any firm conclusions. Further research is needed to provide insights into the role of ibuprofen as adjunct to paracetamol, and other analgesics such as anaesthetic eardrops, for children with AOM.

UV-induced photochemical heterogeneity of dissolved and attached organic matter associated with cyanobacterial blooms in a eutrophic freshwater lake.

PubMed

Xu, Huacheng; Jiang, Helong

2013-11-01

Cyanobacterial blooms represent a significant ecological and human health problem worldwide. In aquatic environments, cyanobacterial blooms are actually surrounded by dissolved organic matter (DOM) and attached organic matter (AOM) that bind with algal cells. In this study, DOM and AOM fractionated from blooming cyanobacteria in a eutrophic freshwater lake (Lake Taihu, China) were irradiated with a polychromatic UV lamp, and the photochemical heterogeneity was investigated using fluorescence excitation-emission matrix (EEM)-parallel factor (PARAFAC) analysis and synchronous fluorescence (SF)-two dimensional correlation spectroscopy (2DCOS). It was shown that a 6-day UV irradiation caused more pronounced mineralization for DOM than AOM (59.7% vs. 41.9%). The EEM-PARAFAC analysis identified one tyrosine-, one humic-, and two tryptophan-like components in both DOM and AOM, and high component photodegradation rates were observed for DOM versus AOM (k > 0.554 vs. <0.519). Moreover, SF-2DCOS found that the photodegradation of organic matters followed the sequence of tyrosine-like > humic-like > tryptophan-like substances. Humic-like substances promoted the indirect photochemical reactions, and were responsible for the higher photochemical rate for DOM. The lower photodegradation of AOM benefited the integrality of cells in cyanobacterial blooms against the negative impact of UV irradiation. Therefore, the photochemical behavior of organic matter was related to the adaptation of enhanced-duration cyanobacterial blooms in aquatic environments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Polyethylene glycol inhibits intestinal neoplasia and induces epithelial apoptosis in Apc(min) mice.

PubMed

Roy, Hemant K; Gulizia, James; DiBaise, John K; Karolski, William J; Ansari, Sajid; Madugula, Madhavi; Hart, John; Bissonnette, Marc; Wali, Ramesh K

2004-11-08

Efficacy of a safe and clinically utilized polyethylene glycol formulation (PEG-3350) to suppress intestinal tumors was investigated in the Apc(min) mouse-model of experimental carcinogenesis. Furthermore, based on our previous finding on the induction of apoptosis in HT-29 cells by PEG, we evaluated its ability to stimulate epithelial cell apoptosis in both Apc(min) mouse as well as AOM-treated rat as a potential molecular mechanism of chemoprevention. Twenty-two Apc(min) mice were randomized equally to PEG or vehicle (control) supplementation. Tumors were scored and uninvolved intestinal mucosal apoptosis was assayed using a modified terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) assay and by immunohistochemical detection of cleaved caspase-3. Supplementation of Apc(min) mice with 10% PEG 3350 (in drinking water) resulted in a 48% (P<0.05) reduction in intestinal tumor burden and induced 2-3 fold increase in mucosal apoptosis. Dietary supplementation of polyethylene glycol (5%) also stimulated colonic mucosal apoptosis 4-5 fold in AOM-treated rats, the regimen that we previously reported to reduce tumor burden by 76% (P<0.05). In summary, we demonstrate, for the first time, that PEG does protect against Apc(min) mouse tumorigenesis. The correlation between pro-apoptotic actions and chemopreventive efficacy of PEG in these models strongly implicates induction of apoptosis as one of the impending mechanisms of chemoprevention.

What not to do in acute otitis media: the top five recommendations proposed by the Italian Society of Preventive and Social Pediatrics.

PubMed

Chiappini, Elena; Bortone, Barbara; Doria, Mattia; Landi, Massimo; Di Mauro, Giuseppe; Marchisio, Paola

2017-10-01

With the aim to reduce inappropriate procedures and antibiotic therapy in the management of acute otitis media (AOM) in children, the Italian Society of Preventive and Social Pediatrics (SIPPS) proposed a top five list of recommendations for clinical practice. Areas covered: AOM is one of the most frequent reasons for antibiotic prescription in pediatric age. The over-estimation of AOM is associated with inappropriate treatment, increased costs, adverse events and spread of antibiotic resistance. Thus, the most recent guidelines provided stringent diagnostic criteria and considered the 'watchful waiting' approach, limiting the immediate antibiotic therapy to a well-characterized subgroup of children. Expert commentary: The five recommendations proposed are: 1) Do not diagnose AOM without having documented the presence of middle ear effusion 2) Do not diagnose AOM without examining the entire tympanic membrane; 3) Do not treat immediately all cases of AOM with antibiotics; 4) Do not administer ear analgesic drops until examining the whole tympanic membrane 5) Do not use macrolides in the AOM therapy. This list of top five recommendations could be a novel tool to spread the key messages on the guidelines and to promote the correct diagnostic procedures as well as a rational use of antibiotics in children.

Haemophilus influenzae type b as an important cause of culture-positive acute otitis media in young children in Thailand: a tympanocentesis-based, multi-center, cross-sectional study

PubMed Central

2014-01-01

Background Streptococcus pneumoniae (S. pneumoniae) and Haemophilus influenzae (H. influenzae) are considered major causes of bacterial acute otitis media (AOM) worldwide, but data from Asia on primary causes of AOM are limited. This tympanocentesis-based, multi-center, cross-sectional study assessed bacterial etiology and antimicrobial susceptibility of AOM in Thailand. Methods Children 3 to 59 months presenting with AOM (< 72 hours of onset) who had not received prescribed antibiotics, or subjects who received prescribed antibiotics but remained symptomatic after 48–72 hours (treatment failures), were eligible. Study visits were conducted from April 2008 to August 2009. Bacteria were identified from middle ear fluid collected by tympanocentesis or spontaneous otorrhea swab sampling (< 20% of cases). S. pneumoniae and H. influenzae serotypes were determined and antimicrobial resistance was also assessed. Results Of the 123 enrolled children, 112 were included in analysis and 48% of the 118 samples were positive for S. pneumoniae (23% (27/118)), H. influenzae (18% (21/118)), Moraxella catarrhalis (6% (7/118)) or Streptococcus pyogenes (3% (4/118)). The most common pneumococcal serotypes were 19F (26%) and 14 (22%). The majority of H. influenzae isolates were encapsulated (18/21), with 13 type b (Hib) representing 62% of all H. influenzae isolate or 11% of all samples (13/118), and there were only 3 non-typeable isolates. Despite high antibiotic resistance, amoxicillin/clavulanate susceptibility was high. No pneumococcal vaccine use was reported. Conclusions S. pneumoniae and H. influenzae, both frequently antibiotic resistant, were leading causes of bacterial AOM and there was an unexpectedly high burden of Hib in this population unvaccinated by any Hib conjugate vaccine. Conjugate vaccines effective against pneumococcus and H. influenzae could potentially reduce the burden of AOM in this population. PMID:24947736

Long-term hearing outcomes after recurrent acute otitis media during early childhood.

PubMed

Krakau, Mattias; Dagöö, Britta Rynnel; Hellström, Sten; Granath, Anna

2017-12-01

To survey long-term hearing outcomes and middle ear pathology in a 30-year follow-up in individuals with onset of recurrent acute otitis media (rAOM) before three years of age. 28 adults, aged 30.1-31.8 years, who originally - at the age of 12-32 months - participated in a study on rAOM between 1979 and 1983, were re-examined regarding self-reported ear problems, current tympanic membrane changes and audiology. Thirteen subjects had suffered from rAOM during early childhood and 15 subjects served as a control group. Recurrent acute otitis media subjects reported hearing problems comparable to those of the controls. Pure tone audiometry, at 125-8000 Hz, did not differ between groups. The rAOM group had a trend for impaired high-frequency (9000-14,000 Hz) threshold levels (9000-14,000 Hz); implying that their cochlear function seemed to have deteriorated. Adults, who suffered from recurrent acute otitis media as infants, did not show any clinically significant hearing loss for pure tone audiometry when compared to controls, but there was a trend for impaired results regarding extended high frequency audiometry (9-14 kHz). Children suffering from rAOM will be at low risk of developing hearing loss and severe middle ear disease.

Beyond lifestyle interventions: exploring the potential of anti‐obesity medications in the UK

PubMed Central

2018-01-01

Summary In the UK, over one‐quarter of the adult population have obesity (body mass index ≥30 kg m−2). This has major implications for patients’ health and the National Health Service. Despite published studies showing that significant weight loss can be achieved and maintained in primary care, and guidance from the National Institute for Health and Care Excellence, weight management services are inconsistently implemented. This may be due primarily to workload and financial constraints. There is also a lack of belief that specialist weight management services and anti‐obesity medications (AOMs) are a viable alternative to bariatric surgery for long‐term maintenance of weight loss. This article discusses the challenges facing obesity management and explores the reasons for the lack of investment in AOMs in the UK to date. The aim of this article is to identify whether the newer AOMs, such as naltrexone/bupropion and liraglutide 3.0 mg, are likely to perform better in a real‐world setting than current or withdrawn AOMs. In addition, it considers whether the equitable provision of specialist weight management services and future clinical trial design could be improved to help identify those individuals most likely to benefit from AOMs and, thus, improve outcomes for people with obesity in the UK. PMID:29689646

Escherichia coli Behavior in the Presence of Organic Matter Released by Algae Exposed to Water Treatment Chemicals

PubMed Central

Bouteleux, C.; Saby, S.; Tozza, D.; Cavard, J.; Lahoussine, V.; Hartemann, P.; Mathieu, L.

2005-01-01

When exposed to oxidation, algae release dissolved organic matter with significant carbohydrate (52%) and biodegradable (55 to 74%) fractions. This study examined whether algal organic matter (AOM) added in drinking water can compromise water biological stability by supporting bacterial survival. Escherichia coli (1.3 × 105 cells ml−1) was inoculated in sterile dechlorinated tap water supplemented with various qualities of organic substrate, such as the organic matter coming from chlorinated algae, ozonated algae, and acetate (model molecule) to add 0.2 ± 0.1 mg of biodegradable dissolved organic carbon (BDOC) liter−1. Despite equivalent levels of BDOC, E. coli behavior depended on the source of the added organic matter. The addition of AOM from chlorinated algae led to an E. coli growth equivalent to that in nonsupplemented tap water; the addition of AOM from ozonated algae allowed a 4- to 12-fold increase in E. coli proliferation compared to nonsupplemented tap water. Under our experimental conditions, 0.1 mg of algal BDOC was sufficient to support E. coli growth, whereas the 0.7 mg of BDOC liter−1 initially present in drinking water and an additional 0.2 mg of BDOC acetate liter−1 were not sufficient. Better maintenance of E. coli cultivability was also observed when AOM was added; cultivability was even increased after addition of AOM from ozonated algae. AOM, likely to be present in treatment plants during algal blooms, and thus potentially in the treated water may compromise water biological stability. PMID:15691924

Acute otitis media disease management.

PubMed

Pichichero, M E; Casey, J R

2003-10-01

A first step in management decisions regarding otitis media must focus on accurate diagnosis to distinguish normal from acute otitis media (AOM) from otitis media with effusion (OME) or a retracted tympanic membrane without middle ear effusion. There are several classification schemes for AOM that may impact management decisions: patients with acute, persistent, recurrent, or chronic AOM may have a different distribution of bacterial pathogens and a different likelihood of success from antimicrobial therapy. Patient age, prior treatment history and daycare attendance are other important variables. The natural history of AOM without antibiotic treatment is generally favorable; however, from the few studies available, this is difficult to quantitate because the diagnosis was infrequently confirmed by tympanocentesis leaving the possibility that many patients entered into these trials may not have had bacterial AOM. Antibiotic choices should reflect pharmacokinetic/pharmacodynamic data and clinical trial results demonstrating effectiveness in eradication of the most likely pathogens based on tympanocentesis sampling and antibiotic sensitivity testing. Thereafter, compliance factors such as formulation, dosing schedule and duration of treatment and accessibility factors such as availability and cost should be taken into account. The increasing prevalence of antibiotic resistance among AOM pathogens and the changing susceptibility profiles of these bacteria should be considered in antibiotic selection. Current best practice recommends amoxicillin for uncomplicated AOM; continuing or switching to an alternative antibiotic based on clinical response after 48 hours of therapy; and selection of second line antibiotics as first line choices when the patient has already been on an antibiotic within the previous month or is otitis prone. Preferred second-line agents frequently noted in various guidelines include amoxicillin/clavulanate, cefdinir, cefpodoxime, cefprozil, and cefuroxime. Three injections of ceftriaxone or gatifloxacin (when approved) or diagnostic/therapeutic tympanocentisis (when approved) become a third-line treatment option. No single antibiotic or management strategy is ideal for all patients.

Otitis Media and Related Complications among Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Adams, Daniel J.; Susi, Apryl; Erdie-Lalena, Christine R.; Gorman, Gregory; Hisle-Gorman, Elizabeth; Rajnik, Michael; Elrod, Marilisa; Nylund, Cade M.

2016-01-01

Acute otitis media (AOM) symptoms can be masked by communication deficits, common to children with autism spectrum disorders (ASD). We sought to evaluate the association between ASD and otitis media. Using ICD-9-CM diagnostic codes, we performed a retrospective case-cohort study comparing AOM, and otitis-related diagnoses among children with and…

AOM optimization with ultra stable high power CO2 lasers for fast laser engraving

NASA Astrophysics Data System (ADS)

Bohrer, Markus

2015-05-01

A new ultra stable CO2 laser in carbon fibre resonator technology with an average power of more than 600W has been developed especially as basis for the use with AOMs. Stability of linear polarisation and beam pointing stability are important issues as well as appropriate shaping of the incident beam. AOMs are tested close to the laser-induced damage threshold with pulses on demand close to one megahertz. Transversal and rotational optimization of the AOMs benefits from the parallel-kinematic principle of a hexapod used for this research.

Inhibition of beta-catenin and KRAS expressions by Piper betle in azoxymethane-induced colon cancer of male Fischer 344 rats.

PubMed

Esa, Faezah; Ngah, Wan Zurinah Wan; Jamal, A Rahman A; Mohd Yusof, Yasmin Anum

2013-12-01

To investigate the chemopreventive effect of Piper betle (PB) on preneoplastic lesions (aberrant crypt foci [ACF]) induced by azoxymethane (AOM) in rats and its effect on colorectal cancer biomarkers (beta-catenin, KRAS, p53 and p21). A total of 32 male Fischer 344 rats were divided into phase 1 and phase 2 groups (8 and 24 weeks of AOM administration, respectively). Each phase was divided into 4 groups: control or normal saline (NS) (1 mL/kg), AOM (15 mg/kg body weight, once weekly for 2 weeks), PB (75 mg/kg body weight) and AOM + PB. PB was force-fed to rats a week after the second dose of AOM and NS. The colon was cut open longitudinally for methylene blue and immunohistochemistry staining. AOM administration showed formation of ACF at 8 and 24 weeks. PB, however, did not reduce ACF formation at either week, but it managed to reduce beta-catenin expression and KRAS found highly expressed in the AOM group of phase 1 rats. No immunoreactivities of p53 and p21 were detected in phase 2 rats, but instead inflammatory cells were visible in between the lesions. PB may act as a potential chemopreventive agent in the early stage of colon carcinogenesis by suppressing the expressions of beta-catenin and KRAS.

Concern and Risk Perception: Effects on Osteoprotective Behaviour

PubMed Central

Barcenilla-Wong, A. L.; Chen, J. S.; March, L. M.

2014-01-01

This study aimed to determine the effect that level of concern for osteoporosis, as well as self-perceived risk of osteoporosis and fracture, has on supplementation use, seeking medical advice, bone mineral density (BMD) testing, and antiosteoporosis medication (AOM) use. Study subjects were 1,095 female Australian participants of the Global Longitudinal study of Osteoporosis in Women (GLOW) untreated for osteoporosis at baseline. Study outcomes from self-administered questionnaires included calcium and vitamin D supplementation, self-reported seeking of medical advice regarding osteoporosis, BMD testing, and AOM use in the last 12 months at the late assessment. Logistic regression was used in the analysis. Concern significantly increased the likelihood of seeking medical advice and, however, had no significant impact on screening or treatment. Heightened self-perceived risks of osteoporosis and fracture both significantly increased the likelihood of seeking medical advice and BMD testing while elevated self-perceived risk of fracture increased AOM use. Supplementation use was not significantly associated with concern levels and risk perception. Concern and risk perceptions to osteoporosis and fracture were significantly associated with certain bone-protective behaviours. However, the disconnect between perceived osteoporosis risk and AOM use illustrates the need to emphasize the connection between osteoporosis and fracture in future education programs. PMID:25276471

Effect of Dietary-Resistant Starch on Inhibition of Colonic Preneoplasia and Wnt Signaling in Azoxymethane-Induced Rodent Models.

PubMed

Nelson, Bridget; Cray, Nicole; Ai, Yongfeng; Fang, Yinan; Liu, Peng; Whitley, Elizabeth M; Birt, Diane

2016-01-01

Dietary fiber has been reported to prevent preneoplastic colon lesions. The aim of this study was to determine the effect of resistant starches, novel dietary fibers, on the development of colonic preneoplasia and Wnt signaling in azoxymethane (AOM)-treated rats and mice fed resistant starches at 55% of the diet after AOM treatment. Another objective was to determine the effect of resistant starches on the development of preneoplasia in rats treated with antibiotics (Ab), administered between AOM treatment and resistant starch feeding. Diets containing resistant starches, high-amylose (HA7), high-amylose-octenyl succinic anhydride (OS-HA7), or high-amylose-stearic acid (SA-HA7) were compared with control cornstarch (CS). The resistant starch content of the diets did not alter the yield of colonic lesions but animals treated with AOM and fed the diet with the highest resistant starch content, SA-HA7 developed the highest average aberrant crypt foci (ACF) per animal. Mice fed the OS-HA7 diet had decreased expression of some upstream Wnt genes in the colonic crypts. This study suggests that further research is needed to determine if resistant starch impacts colon carcinogenesis in rodents.

The effect of the leukotriene antagonist pranlukast on pediatric acute otitis media.

PubMed

Nakamura, Yoshihisa; Hamajima, Yuki; Suzuki, Motohiko; Esaki, Shinichi; Yokota, Makoto; Oshika, Masanori; Takagi, Ippei; Yasui, Keiko; Miyamoto, Naoya; Sugiyama, Kazuko; Nakayama, Meiho; Murakami, Shingo

2016-08-01

Conventional treatment for acute otitis media mainly targets bacteria with antibiotics, neglecting to control for mediators of inflammation. Mediators of inflammation, such as leukotrienes, have been identified in patients with acute otitis media (AOM) or subsequent secretory otitis media (SOM). They can cause functional eustachian tube dysfunction or increase mucous in the middle ear, causing persistent SOM following AOM. The objective of the present study was to evaluate whether or not administration of pranlukast, a widely used leukotriene C4, D4, and E4 antagonist, together with antibiotics could inhibit the progression to SOM. Children with AOM, who were from two to 12 years old, were randomly divided into two groups as follows: a control group in which 50 patients received antibiotic-based conventional treatment according to guidelines for treating AOM proposed by the Japan Otological Society (version 2006); and a pranlukast group, in which 52 patients were administered pranlukast for up to 28 days as well as given conventional treatment. Cases were regarded as persistent SOM when a tympanogram was type B or C2 four weeks after treatment was initiated. Two patients in the pranlukast group and 3 patients in the control group were excluded because they relapsed AOM within 28 days after initial treatment. Therefore, the analysis included 50 and 47 subjects in the pranlukast and control groups, respectively. The percentage of patients diagnosed with persistent SOM (22.0%) was significantly smaller in the pranlukast group compared with the control group (44.7%) (p = 0.018, chi-squared test). The results indicate that combined treatment of AOM with antibiotics and a leukotriene antagonist to control inflammation is useful for preventing progression to persistent SOM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Activation of Intestinal Human Pregnane X Receptor Protects against Azoxymethane/Dextran Sulfate Sodium–Induced Colon Cancer

PubMed Central

Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko

2014-01-01

The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)–induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival rate of PXR-humanized mice, but not wild-type or Pxr-null mice. These data indicated a human PXR–dependent therapeutic chemoprevention of rifaximin toward AOM/DSS-induced colon cancer. Nuclear factor κ-light-chain-enhancer of activated B cells–mediated inflammatory signaling was upregulated in AOM/DSS-treated mice, and inhibited by rifaximin in PXR-humanized mice. Cell proliferation and apoptosis were also modulated by rifaximin treatment in the AOM/DSS model. In vitro cell-based assays further revealed that rifaximin regulated cell apoptosis and cell cycle in a human PXR-dependent manner. These results suggested that specific activation of intestinal human PXR exhibited a chemopreventive role toward AOM/DSS-induced colon cancer by mediating anti-inflammation, antiproliferation, and proapoptotic events. PMID:25277138

Anaerobic methanotrophic communities thrive in deep submarine permafrost.

PubMed

Winkel, Matthias; Mitzscherling, Julia; Overduin, Pier P; Horn, Fabian; Winterfeld, Maria; Rijkers, Ruud; Grigoriev, Mikhail N; Knoblauch, Christian; Mangelsdorf, Kai; Wagner, Dirk; Liebner, Susanne

2018-01-22

Thawing submarine permafrost is a source of methane to the subsurface biosphere. Methane oxidation in submarine permafrost sediments has been proposed, but the responsible microorganisms remain uncharacterized. We analyzed archaeal communities and identified distinct anaerobic methanotrophic assemblages of marine and terrestrial origin (ANME-2a/b, ANME-2d) both in frozen and completely thawed submarine permafrost sediments. Besides archaea potentially involved in anaerobic oxidation of methane (AOM) we found a large diversity of archaea mainly belonging to Bathyarchaeota, Thaumarchaeota, and Euryarchaeota. Methane concentrations and δ 13 C-methane signatures distinguish horizons of potential AOM coupled either to sulfate reduction in a sulfate-methane transition zone (SMTZ) or to the reduction of other electron acceptors, such as iron, manganese or nitrate. Analysis of functional marker genes (mcrA) and fluorescence in situ hybridization (FISH) corroborate potential activity of AOM communities in submarine permafrost sediments at low temperatures. Modeled potential AOM consumes 72-100% of submarine permafrost methane and up to 1.2 Tg of carbon per year for the total expected area of submarine permafrost. This is comparable with AOM habitats such as cold seeps. We thus propose that AOM is active where submarine permafrost thaws, which should be included in global methane budgets.

DNA methylome and transcriptome alterations and cancer prevention by curcumin in colitis-accelerated colon cancer in mice.

PubMed

Guo, Yue; Wu, Renyi; Gaspar, John M; Sargsyan, Davit; Su, Zheng-Yuan; Zhang, Chengyue; Gao, Linbo; Cheng, David; Li, Wenji; Wang, Chao; Yin, Ran; Fang, Mingzhu; Verzi, Michael P; Hart, Ronald P; Kong, Ah-Ng

2018-05-03

Inflammation is highly associated with colon carcinogenesis. Epigenetic mechanisms could play an important role in the initiation and progression of colon cancer. Curcumin, a dietary phytochemical, shows promising effects in suppressing colitis-associated colon cancer in azoxymethane-dextran sulfate sodium (AOM-DSS) mice. However, the potential epigenetic mechanisms of curcumin in colon cancer remain unknown. In this study, the anticancer effect of curcumin in suppressing colon cancer in an 18-week AOM-DSS colon cancer mouse model was confirmed. We identified lists of differentially expressed and differentially methylated genes in pairwise comparisons and several pathways involved in the potential anticancer effect of curcumin. These pathways include LPS/IL-1-mediated inhibition of RXR function, Nrf2-mediated oxidative stress response, production of NO and ROS in macrophages and IL-6 signaling. Among these genes, Tnf stood out with decreased DNA CpG methylation of Tnf in the AOM-DSS group and reversal of the AOM-DSS induced Tnf demethylation by curcumin. These observations in Tnf methylation correlated with increased and decreased Tnf expression in RNA-seq. The functional role of DNA methylation of Tnf was further confirmed by in vitro luciferase transcriptional activity assay. In addition, the DNA methylation level in a group of inflammatory genes was decreased in the AOM+DSS group but restored by curcumin and was validated by pyrosequencing. This study shows for the first time epigenomic changes in DNA CpG methylation in the inflammatory response from colitis-associated colon cancer and the reversal of their CpG methylation changes by curcumin. Future clinical epigenetic studies with curcumin in inflammation-associated colon cancer would be warranted.

Otitis Media and Its Sequelae in Kenyan Schoolchildren.

PubMed

Simões, Eric A F; Kiio, Francis; Carosone-Link, Phyllis J; Ndegwa, Serah N; Ayugi, John; Macharia, Isaac M

2016-12-01

The goal of this study was to obtain representative Kenyan data on the point prevalence of acute otitis media (AOM) and its sequelae (otitis media with effusion [OME] and chronic suppurative otitis media [CSOM]), a major cause of preventable hearing loss in children in developing countries. In Africa, there are limited studies on the prevalence of AOM and its sequelae in children. Study subjects were children aged 2 to 15 years and were enrolled from randomly selected preprimary and primary schools. After parental or guardian consent, subjects had a questionnaire administered, otoscopy and tympanometry were done, and audiometry was performed on those with ear problems detected on these examinations. A total of 9825 (75%) children was from rural schools. The prevalence of CSOM was 15 of 1000, OME was 15 of 1000, and AOM was 7 of 1000 children. Rural Rift Valley schoolchildren had the highest prevalence of CSOM (24 of 1000) compared with other regions (12 of 1000; P < .0001). Ear discharge occurred before 3.5 years in 50% of 901 children with ear discharge. A history of ear discharge was associated with abnormal tympanograms (odds ratio [OR], 11.9-19.2) and mild-to-severe hearing loss (OR, 21.6-38.6), even in children without ear disease (OR, 10.7-24.4). The burden of AOM sequelae in Kenyan preschool and schoolchildren is significant, and it occurs mostly in the first 4 years of life. By preventing early recurrent AOM, pneumococcal vaccination might partly avert nonreversible sequelae. © The Author 2015. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Short-chain fatty acids administration is protective in colitis-associated colorectal cancer development.

PubMed

Tian, Yun; Xu, Qing; Sun, Liqun; Ye, Ying; Ji, Guozhong

2018-03-17

Reduced short-chain fatty acids (SCFAs) have been reported in patients with ulcerative colitis, and increased intake of dietary fiber has shown to be clinically beneficial for colitis. Whether SCFAs suppress tumorigenesis in colitis-associated colorectal cancer remains unknown. The chemopreventive effect of SCFAs in colitis-associated colorectal cancer was evaluated in this study. Model of colitis-associated colorectal cancer in male BALB/c mice was induced by azoxymethane (AOM) and dextran sodium sulfate (DSS). SCFAs mix (67.5 mM acetate, 40 mM butyrate, 25.9 mM propionate) was administered in drink water during the study period. Macroscopic and histological studies were performed to examine the colorectal inflammation and tumorigenesis in AOM/DSS-induced mice treated with or without SCFA mix. The effects of SCFAs mix on colonic epithelial cellular proliferation were also assessed using Ki67 immunohistochemistry and TUNEL staining. The administration of SCFAs mix significantly reduced the tumor incidence and size in mice with AOM/DSS-induced colitis associated colorectal cancer. SCFAs mix protected from AOM/DSS-induced colorectal cancer by improving colon inflammation and disease activity index score as well as suppressing the expression of proinflammatory cytokines including IL-6, TNF-α and IL-17. A decrease in cell proliferation markers and an increase in TUNEL-positive tumor epithelial cells were also demonstrated in AOM/DSS mice treated with SCFAs mix. SCFAs mix administration prevented development of tumor and attenuated the colonic inflammation in a mouse model of colitis-associated colorectal cancer. SCFAs mix may be a potential agent in the prevention and treatment of colitis-associated colorectal cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

Otitis Media and Related Complications Among Children with Autism Spectrum Disorders.

PubMed

Adams, Daniel J; Susi, Apryl; Erdie-Lalena, Christine R; Gorman, Gregory; Hisle-Gorman, Elizabeth; Rajnik, Michael; Elrod, Marilisa; Nylund, Cade M

2016-05-01

Acute otitis media (AOM) symptoms can be masked by communication deficits, common to children with autism spectrum disorders (ASD). We sought to evaluate the association between ASD and otitis media. Using ICD-9-CM diagnostic codes, we performed a retrospective case-cohort study comparing AOM, and otitis-related diagnoses among children with and without ASD. Children with ASD had a significantly increased rate of AOM, otitis media with effusion, otorrhea, and PE tube placement. Children with ASD were more than twice as likely to develop mastoiditis, and to undergo mastoidectomy and tympanoplasty. Children with ASD are more likely to have middle ear infections and otitis-related complications, highlighting the importance of routine middle ear examinations and close attention to hearing impairment in this population.

Effect of vitamin C on azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis-associated early colon cancer in mice.

PubMed

Jeon, Hee-Jin; Yeom, Yiseul; Kim, Yoo-Sun; Kim, Eunju; Shin, Jae-Ho; Seok, Pu Reum; Woo, Moon Jea; Kim, Yuri

2018-04-01

The objective of this study was to investigate the effects of vitamin C on inflammation, tumor development, and dysbiosis of intestinal microbiota in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced inflammation-associated early colon cancer mouse model. Male BALB/c mice were injected intraperitoneally with AOM [10 mg/kg body weight (b.w)] and given two 7-d cycles of 2% DSS drinking water with a 14 d inter-cycle interval. Vitamin C (60 mg/kg b.w. and 120 mg/kg b.w.) was supplemented by gavage for 5 weeks starting 2 d after the AOM injection. The vitamin C treatment suppressed inflammatory morbidity, as reflected by disease activity index (DAI) in recovery phase and inhibited shortening of the colon, and reduced histological damage. In addition, vitamin C supplementation suppressed mRNA levels of pro-inflammatory mediators and cytokines, including cyclooxygenase-2, microsomal prostaglandin E synthase-2, tumor necrosis factor-α, Interleukin (IL)-1β , and IL-6 , and reduced expression of the proliferation marker, proliferating cell nuclear antigen, compared to observations of AOM/DSS animals. Although the microbial composition did not differ significantly between the groups, administration of vitamin C improved the level of inflammation-related Lactococcus and JQ084893 to control levels. Vitamin C treatment provided moderate suppression of inflammation, proliferation, and certain inflammation-related dysbiosis in a murine model of colitis associated-early colon cancer. These findings support that vitamin C supplementation can benefit colonic health. Long-term clinical studies with various doses of vitamin C are warranted.

Stringently Defined Otitis Prone Children Demonstrate Deficient Naturally Induced Mucosal Antibody Response to Moraxella catarrhalis Proteins

PubMed Central

Ren, Dabin; Murphy, Timothy F.; Lafontaine, Eric R.; Pichichero, Michael E.

2017-01-01

Moraxella catarrhalis (Mcat) is a prominent mucosal pathogen causing acute otitis media (AOM). We studied Mcat nasopharyngeal (NP) colonization, AOM frequency and mucosal antibody responses to four vaccine candidate Mcat proteins: outer membrane protein (OMP) CD, oligopeptide permease (Opp) A, hemagglutinin (Hag), and Pilin A clade 2 (PilA2) from stringently defined otitis prone (sOP) children, who experience the greatest burden of disease, compared to non-otitis prone (NOP) children. sOP children had higher NP colonization of Mcat (30 vs. 22%, P = 0.0003) and Mcat-caused AOM rates (49 vs. 24%, P < 0.0001) than NOP children. Natural acquisition of mucosal antibodies to Mcat proteins OMP CD (IgG, P < 0.0001), OppA (IgG, P = 0.018), Hag (IgG and IgA, both P < 0.0001), and PilA2 (IgA, P < 0.0001) was lower in sOP than NOP children. Higher levels of mucosal IgG to Hag (P = 0.039) and PilA2 (P = 0.0076), and IgA to OMP CD (P = 0.010), OppA (P = 0.030), and PilA2 (P = 0.043) were associated with lower carriage of Mcat in NOP but not sOP children. Higher levels of mucosal IgG to OMP CD (P = 0.0070) and Hag (P = 0.0003), and IgA to Hag (P = 0.0067) at asymptomatic colonization than those at onset of AOM were associated with significantly lower rate of Mcat NP colonization progressing to AOM in NOP compared to sOP children (3 vs. 26%, P < 0.0001). In conclusion, sOP children had a diminished mucosal antibody response to Mcat proteins, which was associated with higher frequencies of asymptomatic NP colonization and NP colonization progressing to Mcat-caused AOM. Enhancing Mcat antigen-specific mucosal immune responses to levels higher than achieved by natural exposure will be necessary to prevent AOM in sOP children. PMID:28848555

Stringently Defined Otitis Prone Children Demonstrate Deficient Naturally Induced Mucosal Antibody Response to Moraxella catarrhalis Proteins.

PubMed

Ren, Dabin; Murphy, Timothy F; Lafontaine, Eric R; Pichichero, Michael E

2017-01-01

Moraxella catarrhalis ( Mcat ) is a prominent mucosal pathogen causing acute otitis media (AOM). We studied Mcat nasopharyngeal (NP) colonization, AOM frequency and mucosal antibody responses to four vaccine candidate Mcat proteins: outer membrane protein (OMP) CD, oligopeptide permease (Opp) A, hemagglutinin (Hag), and Pilin A clade 2 (PilA2) from stringently defined otitis prone (sOP) children, who experience the greatest burden of disease, compared to non-otitis prone (NOP) children. sOP children had higher NP colonization of Mcat (30 vs. 22%, P  = 0.0003) and Mcat -caused AOM rates (49 vs. 24%, P  < 0.0001) than NOP children. Natural acquisition of mucosal antibodies to Mcat proteins OMP CD (IgG, P  < 0.0001), OppA (IgG, P  = 0.018), Hag (IgG and IgA, both P  < 0.0001), and PilA2 (IgA, P  < 0.0001) was lower in sOP than NOP children. Higher levels of mucosal IgG to Hag ( P  = 0.039) and PilA2 ( P  = 0.0076), and IgA to OMP CD ( P  = 0.010), OppA ( P  = 0.030), and PilA2 ( P  = 0.043) were associated with lower carriage of Mcat in NOP but not sOP children. Higher levels of mucosal IgG to OMP CD ( P  = 0.0070) and Hag ( P  = 0.0003), and IgA to Hag ( P  = 0.0067) at asymptomatic colonization than those at onset of AOM were associated with significantly lower rate of Mcat NP colonization progressing to AOM in NOP compared to sOP children (3 vs. 26%, P  < 0.0001). In conclusion, sOP children had a diminished mucosal antibody response to Mcat proteins, which was associated with higher frequencies of asymptomatic NP colonization and NP colonization progressing to Mcat -caused AOM. Enhancing Mcat antigen-specific mucosal immune responses to levels higher than achieved by natural exposure will be necessary to prevent AOM in sOP children.

Anaerobic Oxidation of Methane in Sediments of Two Boreal Lakes

NASA Astrophysics Data System (ADS)

Tiirola, M. A.; Rissanen, A. J.; Karvinen, A.; Nykänen, H.; Mpamah, P.; Peura, S.; Kankaala, P.

2014-12-01

In this study, potential for Anaerobic oxidation of methane (AOM) coupled with metal reduction was studied in boreal lake sediments. Slurries of sediment samples collected from two sites in southeastern Finland, i.e. from Lake Orivesi, Heposelkä, an vegetated littoral site, dominated by Phragmites australis (Sample Sa, sediment layer 0 - 25 cm) and from the profundal zone of a mesotrophic Lake Ätäskö (Aa, 0 - 10 cm; Ab, 10 - 30 cm; Ac, 90 - 130 cm), were incubated in laboratory in anaerobic conditions at in situ temperatures for up to 5 months. The samples were amended either 1) with 13CH4, 2) 13CH4 + manganese(IV) oxide (MnO2) or 3) 13CH4 + iron(III) hydroxide (Fe(OH)3), and the processes were measured by following the 13C transfer to the carbon dioxide (CO2) pool and by concentration measurements of CH4 and CO2. Changes in microbial communities were studied from DNA extracted from sediment samples before and after incubation period by next-generation sequencing (Ion Torrent) of polymerase chain reaction (PCR) - amplified bacterial and archaeal 16S rRNA and methyl coenzyme-M reductase gene (mcrA) amplicons. AOM took place in every sample except in deepest sample (Ac) with potential rates up to 2.1 nmol CH4 d-1 g-1wetsedim (~2 nmol d-1 cm-3) which are considerably lower than previously reported metal-driven AOM in marine sediments (10-40 nmol d-1 cm-3) but within a range of NO3- -driven AOM in an oligotrophic lake (0.6-3.6 nmol d-1 cm-3). AOM took place without metal additions but addition of Mn4+ increased the potential rates and this increase was especially high in 10-30 cm layer (Ab) of the profundal site (5-fold increase). The structure of the bacterial and archaeal communities changed considerably during incubation. Communities incubated with Mn4+ were especially different from those incubated with Fe3+ or without metals which were more similar with each other. Surprisingly, anaerobic methanotrophic archaea detected, ANME-2D and AOM-associated archaea (AAA), were almost absent in the littoral site and constituted only up to 3.5% and 5% of archaeal 16S rRNA and mcrA gene sequences, respectively, in the profundal site. Mn4+ induced an increase in the abundance of ANME-2D and AAA in the profundal site which indicates that they are involved in Mn4+ - dependent AOM.

The health care burden and societal impact of acute otitis media in seven European countries: results of an Internet survey.

PubMed

Wolleswinkel-van den Bosch, Judith H; Stolk, Elly A; Francois, Martine; Gasparini, Roberto; Brosa, Max

2010-11-19

This paper estimates medical resource use, direct costs, and productivity losses and costs (indirect costs) during episodes of acute otitis media (AOM) in young children. A 24-item Internet questionnaire was developed for parents in Belgium (Flanders), France, Germany, Italy, The Netherlands, Spain, and the United Kingdom (UK) to report health care resource use and productivity losses during the most recent episode of AOM in their child, younger than 5 years. The percentage who did not seek medical help for AOM was considerable in The Netherlands (28.3%) and the UK (19.7%). Antibiotic use was high, ranging from 60.8% (Germany) to 87.1% (Italy). Total costs per AOM episode ranged from €332.00 (The Netherlands) to €752.49 (UK). Losses in productivity accounted for 61% (France) to 83% (Germany) of the total costs. AOM poses a significant medical and economic burden to society. Copyright © 2010 Elsevier Ltd. All rights reserved.

Spectra analysis of nonuniform FBG-based acousto-optic modulator by using Fourier mode coupling theory.

PubMed

Liu, Chao; Pei, Li; Li, Zhuoxuan; Ning, Tigang; Yu, Shaowei; Kang, Zexin

2013-05-10

Fourier mode coupling theory was first employed in the spectral analysis of several nonuniform fiber Bragg grating (FBG)-based acousto-optic modulators (NU-FBG-AOMs) with the effects of Gaussian-apodization (GA), phase shift (PS), and linear chirp (LC). Because of the accuracy and simplicity of the algorithm applied in this model, the modulation performances of these modulators can be acquired effectively and efficiently. Based on the model, the reflected spectra of these modulators were simulated under various acoustic frequencies and acoustically induced strains. The simulation results of the GA-FBG-AOM and PS-FBG-AOM showed that the wavelength spacing between the primary reflection peak and the secondary reflection peak is proportional to the acoustic frequency, and the reflectivity of reflection peaks depends on the acoustically induced strains. But for the LC-FBG-AOM, the wavelength spacing between the neighboring reflection peaks increased linearly and inversely with the acoustic frequency, and the extinction ratio of each peak relates to the acoustically induced strain. These numerical analysis results, which were effectively used in the designs and fabrications of these NU-FBG-AOMs, can broaden the AOM-based application scope and shed light on the performance optimization of optical wavelength-division multiplex system.

Assessing Transformations of Algal Organic Matter in the Long-Term: Impacts of Humification-Like Processes

PubMed Central

Leloup, Maud; Pallier, Virginie; Nicolau, Rudy; Feuillade-Cathalifaud, Geneviève

2015-01-01

Algae and cyanobacteria are important contributors to the natural organic matter (NOM) of eutrophic water resources. The objective of this work is to increase knowledge on the modifications of algal organic matter (AOM) properties in the long term to anticipate blooms footprint in such aquatic environments. The production of AOM from an alga (Euglena gracilis) and a cyanobacteria (Microcystis aeruginosa) was followed up and characterized during the stationary phase and after one year and four months of cultivation, in batch experiments. Specific UV absorbance (SUVA) index, organic matter fractionation according to hydrophobicity and apparent molecular weight were combined to assess the evolution of AOM. A comparison between humic substances (HS) mainly derived from allochthonous origins and AOM characteristics was performed to hypothesize impacts of AOM transformation processes on the water quality of eutrophic water resources. Each AOM fraction underwent a specific evolution pattern, depending on its composition. Impacts of humification-like processes were predominant over release of biopolymers due to cells decay and led to an increase in the hydrophobic compounds part and molecular weights over time. However, the hydrophilic fraction remained the major fraction whatever the growth stage. Organic compounds generated by maturation of these precursors corresponded to large and aliphatic structures. PMID:26251898

Improved tympanic thermometer based on a fiber optic infrared radiometer and an otoscope and its use as a new diagnostic tool for acute otitis media

NASA Astrophysics Data System (ADS)

Fishman, Gadi; DeRowe, Ari; Ophir, Eyal; Scharf, Vered; Shabtai, Abraham; Ophir, Dov; Katzir, Abraham

1999-06-01

Clinical diagnosis of acute otitis media (AOM) in children is not easy. It was assumed that there is a difference ΔT between the Tympanic Membrane (TM) temperatures in the two ears in unilateral AOM and that an accurate measurement of ΔT may improve the diagnosis accuracy. An IR transmitting fiber, made of AgClBr, was coupled into a hand held otoscope and was used for the non-contact (radiometric) measurements of TT, the TM temperature. Experiments were carried out, first, on a laboratory model that simulated the human ear, including an artificial tympanic membrane and an artificial ear canal. Measurements carried out using commercially available tympanic thermometers shown that the temperature Tc of the ear canal affected the results. Tc did not affect the fiberoptic radiometer, and this device accurately measured the true temperature, TT of the tympanic membrane. A prospective blinded sampling of the TM temperature was then performed on 48 children with suspected AOM. The mean temperature difference between the ears, for children with unilateral AOM was ΔT = (0.68 +/- 0.27)°C. For children with bilateral AOM it was ΔT = (0.14+/-0.10)°C (p<0.001). It was demonstrated that afor unilateral AOM the difference ΔT was proportional to the systemic temperature. In conclusion, the fiberoptic interferometric measurements of the TM can be a useful non-invasive diagnostic tool for AOM, when combined with other data.

Anaerobic oxidation of methane (AOM) in marine sediments from the Skagerrak (Denmark): II. Reaction-transport modeling

NASA Astrophysics Data System (ADS)

Dale, A. W.; Regnier, P.; Knab, N. J.; Jørgensen, B. B.; Van Cappellen, P.

2008-06-01

A steady-state reaction-transport model is applied to sediments retrieved by gravity core from two stations (S10 and S13) in the Skagerrak to determine the main kinetic and thermodynamic controls on anaerobic oxidation of methane (AOM). The model considers an extended biomass-implicit reaction network for organic carbon degradation, which includes extracellular hydrolysis of macromolecular organic matter, fermentation, sulfate reduction, methanogenesis, AOM, acetogenesis and acetotrophy. Catabolic reaction rates are determined using a modified Monod rate expression that explicitly accounts for limitation by the in situ catabolic energy yields. The fraction of total sulfate reduction due to AOM in the sulfate-methane transition zone (SMTZ) at each site is calculated. The model provides an explanation for the methane tailing phenomenon which is observed here and in other marine sediments, whereby methane diffuses up from the SMTZ to the top of the core without being consumed. The tailing is due to bioenergetic limitation of AOM in the sulfate reduction zone, because the methane concentration is too low to engender favorable thermodynamic drive. AOM is also bioenergetically inhibited below the SMTZ at both sites because of high hydrogen concentrations (∼3-6 nM). The model results imply there is no straightforward relationship between pore water concentrations and the minimum catabolic energy needed to support life because of the highly coupled nature of the reaction network. Best model fits are obtained with a minimum energy for AOM of ∼11 kJ mol-1, which is within the range reported in the literature for anaerobic processes.

Tea Polysaccharide Prevents Colitis-Associated Carcinogenesis in Mice by Inhibiting the Proliferation and Invasion of Tumor Cells

PubMed Central

Liu, Li-Qiao; Li, Hai-Shan; Shen, Ming-Yue; Hu, Jie-Lun; Xie, Ming-Yong

2018-01-01

The imbalance between cell proliferation and apoptosis can lead to tumor progression, causing oncogenic transformation, abnormal cell proliferation and cell apoptosis suppression. Tea polysaccharide (TPS) is the major bioactive component in green tea, it has showed antioxidant, antitumor and anti-inflammatory bioactivities. In this study, the chemoprophylaxis effects of TPS on colitis-associated colon carcinogenesis, especially the cell apoptosis activation and inhibition effects on cell proliferation and invasion were analyzed. The azoxymethane/dextran sulfate sodium (AOM/DSS) was used to induce the colorectal carcinogenesis in mice. Results showed that the tumor incidence was reduced in TPS-treated AOM/DSS mice compared to AOM/DSS mice. TUNEL staining and Ki-67 immunohistochemistry staining showed that the TPS treatment increased significantly the cell apoptosis and decreased cell proliferation among AOM/DSS mice. Furthermore, TPS reduced the expression levels of the cell cycle protein cyclin D1, matrix metalloproteinase (MMP)-2, and MMP-9. In addition, in vitro studies showed that TPS, suppressed the proliferation and invasion of the mouse colon cancer cells. Overall, our findings demonstrated that TPS could be a potential agent in the treatment and/or prevention of colon tumor, which promoted the apoptosis and suppressed the proliferation and invasion of the mouse colon cancer cells via arresting cell cycle progression. PMID:29419740

Reduced Memory CD4+ T-Cell Generation in the Circulation of Young Children May Contribute to the Otitis-Prone Condition

PubMed Central

Sharma, Sharad K.; Casey, Janet R.

2011-01-01

Background. An explanation for the immunologic dysfunction that causes children to be prone to repeated episodes of acute otitis media (AOM) has long been sought. Poor antibody response has been associated with the otitis-prone condition; however, there is no precise mechanistic explanation for this condition. Methods. Non–otitis-prone and otitis-prone children with AOM or nasopharyngeal (NP) colonization caused by either Streptococcus pneumoniae or Haemophilus influenzae were compared for pathogen-specific CD4+ T-helper memory responses by stimulating peripheral blood mononuclear cells using 6 vaccine candidate S. pneumoniae and 3 H. influenzae protein antigens. Samples were analyzed by multi-parameter flow cytometry. Results. Significantly reduced percentages of functional CD45RALow memory CD4+ T cells producing specific cytokines (interferon γ, interleukin [IL]–2, IL-4 and IL-17a) were observed in otitis-prone children following AOM and NP colonization with either S. pneumoniae or H. influenzae. Immunoglobulin (Ig) G responses to the studied protein antigens were reduced, which suggests that antigen-specific B-cell function may be compromised as a result of poor T-cell help. Staphylococcal enterotoxin B stimulated similar cytokine patterns in memory CD4+T cells in both groups of children. Conclusions. Otitis-prone children have suboptimal circulating functional T-helper memory and reduced IgG responses to S. pneumoniae or H. influenzae after colonization and after AOM; this immune dysfunction causes susceptibility to recurrent AOM infections. PMID:21791667

Antibody response to Streptococcus pneumoniae proteins PhtD, LytB, PcpA, PhtE and Ply after nasopharyngeal colonization and acute otitis media in children.

PubMed

Pichichero, Michael E; Kaur, Ravinder; Casey, Janet R; Xu, Qingfu; Almudevar, Anthony; Ochs, Martina

2012-06-01

We prospectively compared serum antibody levels of 5 Streptococcus pneumoniae (Spn) proteins: PcpA PhtD, PhtE Ply and LytB associated with nasopharyngeal (NP) colonization and acute otitis media (AOM) infection in a cohort of 6-30 mo old children. Antigen-specific antibody titers were determined by ELISA. A total of 731 visits among 168 children were studied. There were 301 Spn NP colonization episodes documented in 109 (65%) children and 42 Spn AOM episodes in 34 (20%) children. IgG antibody titers to the 5 proteins were significantly different among children over time (p < 0.001), with a rank order as follows: PcpA > PhtE = PhtD > Ply > LytB Characterization of IgG and IgM acute and convalescent serum antibody levels of Spn AOM infection showed the kinetics of the response differed among children, with the same rank order of antibody levels over time. Individual data showed that some children responded to AOM with an antibody increase to one or more of these Spn proteins but some children failed to respond. We conclude that antibody levels to Spn proteins PcpA PhtD, PhtE, Ply and LytB, all rise over time in children age 6 to 30 mo following natural exposure to Spn after NP colonization and AOM; however, there were significant differences in quantity of antibody elicited among these potential vaccine antigens.

Effect of vitamin C on azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis-associated early colon cancer in mice

PubMed Central

2018-01-01

BACKGROUND/OBJECTIVES The objective of this study was to investigate the effects of vitamin C on inflammation, tumor development, and dysbiosis of intestinal microbiota in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced inflammation-associated early colon cancer mouse model. MATERIALS/METHODS Male BALB/c mice were injected intraperitoneally with AOM [10 mg/kg body weight (b.w)] and given two 7-d cycles of 2% DSS drinking water with a 14 d inter-cycle interval. Vitamin C (60 mg/kg b.w. and 120 mg/kg b.w.) was supplemented by gavage for 5 weeks starting 2 d after the AOM injection. RESULTS The vitamin C treatment suppressed inflammatory morbidity, as reflected by disease activity index (DAI) in recovery phase and inhibited shortening of the colon, and reduced histological damage. In addition, vitamin C supplementation suppressed mRNA levels of pro-inflammatory mediators and cytokines, including cyclooxygenase-2, microsomal prostaglandin E synthase-2, tumor necrosis factor-α, Interleukin (IL)-1β, and IL-6, and reduced expression of the proliferation marker, proliferating cell nuclear antigen, compared to observations of AOM/DSS animals. Although the microbial composition did not differ significantly between the groups, administration of vitamin C improved the level of inflammation-related Lactococcus and JQ084893 to control levels. CONCLUSION Vitamin C treatment provided moderate suppression of inflammation, proliferation, and certain inflammation-related dysbiosis in a murine model of colitis associated-early colon cancer. These findings support that vitamin C supplementation can benefit colonic health. Long-term clinical studies with various doses of vitamin C are warranted. PMID:29629026

Assessing the High Temperature, High Pressure Subsurface for Anaerobic Methane Oxidation

NASA Astrophysics Data System (ADS)

Harris, R. L.; Bartlett, D.; Byrnes, A. W.; Walsh, K. M.; Lau, C. Y. M.; Onstott, T. C.

2017-12-01

The anaerobic oxidation of methane (AOM) is an important sink in the global methane (CH4) budget. ANMEs are known to oxidize CH4 either independently or in consortia with bacteria, coupling the reduction of electron acceptors such as, SO42-, NO2-, NO3-, Mn4+, or Fe3+. To further constrain the contribution of AOM to the global CH4 budget, it is important to assess unexplored environments where AOM is thermodynamically possible such as the high pressure, high temperature deep biosphere. Provided plausible electron acceptor availability, increased temperature and pCH4 yield favorable Gibbs free energies for AOM reactions and the production of ATP (Fig. 1). To date, only sulfate-dependent AOM metabolism has been documented under high temperature conditions (50-72˚C), and AOM has not been assessed above 10.1 MPa. Given that ANMEs share close phylogenetic and metabolic heritage with methanogens and that the most heat-tolerant microorganism known is a barophilic methanogen, there possibly exist thermophilic ANMEs. Here we describe preliminary results from high pressure, high temperature stable isotope tracer incubation experiments on deep biosphere samples. Deep sub-seafloor sediments collected by IODP 370 from the Nankai Trough (257 - 865 m below seafloor) and deep fracture fluid from South Africa (1339 m below land surface) were incubated anaerobically in hydrostatic pressure vessels at 40 MPa in simulated in situ temperatures (40˚ - 80˚C). Sediments and fracture fluid were incubated in sulfate-free artificial seawater, a 2:98 13CH4:N2 headspace, and treated with one of the potential electron acceptors listed above in addition to kill and endogenous activity (i.e. no added electron acceptor) controls. Stable isotope analysis of dissolved inorganic carbon (DIC) suggests that AOM occurred within 60 days of incubation for all investigated electron acceptors and temperatures except 50˚C. Sulfate-dependent AOM rates are consistent with those previously reported in the literature, while the highest rate of AOM was measured in Nankai Trough sediments from 616 m incubated at 70˚C with 10 mM NO2- (0.44 ± .01 µmol 13CO2 day-1 g-1 dry weight sediment). Further analysis is required to investigate the identities and functional adaptations of CH4-cycling organisms active under high pressure and high temperature.

Chemopreventive effects of standardized ethanol extract from the aerial parts of Artemisia princeps Pampanini cv. Sajabal via NF-κB inactivation on colitis-associated colon tumorigenesis in mice.

PubMed

Chung, Kyung-Sook; Choi, Hye-Eun; Shin, Ji-Sun; Cho, Eu-Jin; Cho, Young-Wuk; Choi, Jung-Hye; Baek, Nam-In; Lee, Kyung-Tae

2015-01-01

Chronic inflammation is an underlying risk factor of colon cancer, and NF-κB plays a critical role in the development of inflammation-associated colon cancer in an AOM/DSS mouse model. The aim of this study was to determine whether the standardized ethanol extract obtained from the aerial parts of Artemisia princeps Pampanini cv. Sajabal (EAPP) is effective at preventing inflammation-associated colon cancer, and if so, to identify the signaling pathways involved. In the present study, protective efficacy of EAPP on tumor formation and the infiltrations of monocytes and macrophages in colons of an AOM/DSS mouse model were evaluated. It was found that colitis and tumor burdens showed statistically meaningful improvements after EAPP administration. Furthermore, these improvements were accompanied by a reduction in NF-κB activity and in the levels of NF-κB-dependent pro-survival proteins, that is, survivin, cFLIP, XIAP, and Bcl-2. In vitro, EAPP significantly reduced NF-κB activation and the levels of IL-1β and IL-8 mRNA and pro-survival proteins in HT-29 and HCT-116 colon cancer cells. Furthermore, EAPP caused caspase-dependent apoptosis. Based on these results, the authors suggest EAPP suppresses inflammatory responses and induces apoptosis partly via NF-κB inactivation, and that EAPP could be useful for the prevention of colitis-associated tumorigenesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

New Pneumococcal Carriage Acquired in Association with Acute Respiratory Infection Is Prone to Cause Otitis Media.

PubMed

Auranen, Kari; Syrjänen, Ritva; Leino, Tuija; Kilpi, Terhi

2016-01-01

For considering vaccine-prevention of pneumococcal acute otitis media (PncAOM), relationships between pneumococcal carriage, respiratory infection and PncAOM need to be understood. We analyzed nasopharyngeal samples collected from 329 unvaccinated Finnish children aged 2-24 months at scheduled visits and at visits during respiratory infection in 1994-97. We assessed temporal associations of respiratory infection with pneumococcal acquisition and whether PncAOM hazard depends on the relative timing of acquisition and the infection onset. The data comprised 607 person-years of risk-time for acquisition, 245 person-months of concurrent respiratory infection and carriage, and 119 episodes of PncAOM. The acquisition hazard was 3-fold in the month preceding respiratory sickness (hazard ratio, HR 3.5, 90% credible interval CI 2.9, 4.1) as compared to acquisition in healthy children. Moreover, the PncAOM hazard was markedly higher (HR 3.7, 90% CI 2.4, 5.3) during the first month of carriage acquired around the acute phase of respiratory infection (between 1 month before and 1 week after the sickness onset), as compared to carriage acquired later during sickness. The high proportion (76%) of PncAOM events occurring within 1 month of acquisition was due to frequent acquisition being associated with respiratory infection as well as the susceptibility of such acquisition to cause otitis media.

Factors Affecting Loss of Tympanic Membrane Mobility in Acute Otitis Media Model of Chinchilla

PubMed Central

Guan, Xiying; Chen, Yongzheng; Gan, Rong Z.

2014-01-01

Recently we reported that middle ear pressure (MEP), middle ear effusion (MEE), and ossicular changes each contribute to the loss of tympanic membrane (TM) mobility in a guinea pig model of acute otitis media (AOM) induced by S. pneumoniae (Guan and Gan, 2013). However, it is not clear how those factors vary along the course of the disease and whether those effects are reproducible in different species. In this study, a chinchilla AOM model was produced by transbullar injection of Haemophilus influenzae. Mobility of the TM at the umbo was measured by laser vibrometry in two treatment groups: 4 days (4D) and 8 days (8D) post inoculation. These time points represent relatively early and later phases of AOM. In each group, the vibration of the umbo was measured at three experimental stages: unopened, pressure-released, and effusion-removed ears. The effects of MEP and MEE and middle ear structural changes were quantified in each group by comparing the TM mobility at one stage with that of the previous stage. Our findings show that the factors affecting TM mobility do change with the disease time course. The MEP was the dominant contributor to reduction of TM mobility in 4D AOM ears, but showed little effect in 8D ears when MEE filled the tympanic cavity. MEE was the primary factor affecting TM mobility loss in 8D ears, but affected the 4D ears only at high frequencies. After the release of MEP and removal of MEE, residual loss of TM mobility was seen mainly at low frequencies in both 4D and 8D ears, and was associated with middle ear structural changes. Our findings establish that the factors contributing to TM mobility loss in the chinchilla ear were similar to those we reported previously for the guinea pig ears with AOM. Outcomes did not appear to differ between the two major bacterial species causing AOM in these animal models. PMID:24406734

Inhibitory effects of astaxanthin on azoxymethane-induced colonic preneoplastic lesions in C57/BL/KsJ-db/db mice.

PubMed

Kochi, Takahiro; Shimizu, Masahito; Sumi, Takafumi; Kubota, Masaya; Shirakami, Yohei; Tanaka, Takuji; Moriwaki, Hisataka

2014-12-17

Obesity and related metabolic abnormalities, including excess oxidative stress and chronic inflammation, are associated with colorectal carcinogenesis. Astaxanthin, a xanthophyll carotenoid found in aquatic animals, is known to possess antioxidant, anti-inflammatory, and antineoplastic properties. The present study examined the effects of astaxanthin on the development of azoxymethane (AOM)-induced colonic premalignant lesions in C57BL/KsJ-db/db (db/db) obese mice. Male db/db mice were administered 4 weekly subcutaneous injections of AOM (15 mg/kg body weight) from 5 weeks of age and subsequently, from 1 week after the last injection of AOM, were fed a diet containing 200 ppm astaxanthin throughout the experiment (8 weeks). The development of colonic premalignant lesions, i.e., aberrant crypt foci and β-catenin accumulated crypts, was significantly inhibited in mice treated with astaxanthin than in mice fed the basal diet. Astaxanthin administration markedly reduced urinary levels of 8-OHdG and serum levels of d-ROMs, which are oxidative stress markers, while increasing the expression of mRNA for the antioxidant enzymes GPx1, SOD1, and CAT in the colonic mucosa of AOM-treated db/db mice. The expression levels of IL-1β, IL-6, F4/80, CCL2, and CXCL2 mRNA in the colonic mucosa of AOM-treated mice were significantly decreased by astaxanthin. Dietary feeding with astaxanthin also resulted in a reduction in the numbers of NF-κB- and PCNA-positive cells that were increased by AOM exposure, in the colonic epithelium. These findings suggest that astaxanthin inhibits the development of colonic premalignant lesions in an obesity-related colorectal carcinogenesis model by reducing oxidative stress, attenuating chronic inflammation, and inhibiting NF-κB activation and cell proliferation in the colonic mucosa. Astaxanthin, therefore, may be a potential candidate as a chemoprevention agent against colorectal carcinogenesis in obese individuals.

Childhood Otitis Media: A Cohort Study With 30-Year Follow-Up of Hearing (The HUNT Study).

PubMed

Aarhus, Lisa; Tambs, Kristian; Kvestad, Ellen; Engdahl, Bo

2015-01-01

To study the extent to which otitis media (OM) in childhood is associated with adult hearing thresholds. Furthermore, to study whether the effects of OM on adult hearing thresholds are moderated by age or noise exposure. Population-based cohort study of 32,786 participants who had their hearing tested by pure-tone audiometry in primary school and again at ages ranging from 20 to 56 years. Three thousand sixty-six children were diagnosed with hearing loss; the remaining sample had normal childhood hearing. Compared with participants with normal childhood hearing, those diagnosed with childhood hearing loss caused by otitis media with effusion (n = 1255), chronic suppurative otitis media (CSOM; n = 108), or hearing loss after recurrent acute otitis media (rAOM; n = 613) had significantly increased adult hearing thresholds in the whole frequency range (2 dB/17-20 dB/7-10 dB, respectively). The effects were adjusted for age, sex, and noise exposure. Children diagnosed with hearing loss after rAOM had somewhat improved hearing thresholds as adults. The effects of CSOM and hearing loss after rAOM on adult hearing thresholds were larger in participants tested in middle adulthood (ages 40 to 56 years) than in those tested in young adulthood (ages 20 to 40 years). Eardrum pathology added a marginally increased risk of adult hearing loss (1-3 dB) in children with otitis media with effusion or hearing loss after rAOM. The study could not reveal significant differences in the effect of self-reported noise exposure on adult hearing thresholds between the groups with OM and the group with normal childhood hearing. This cohort study indicates that CSOM and rAOM in childhood are associated with adult hearing loss, underlining the importance of optimal treatment in these conditions. It appears that ears with a subsequent hearing loss after OM in childhood age at a faster rate than those without; however this should be confirmed by studies with several follow-up tests through adulthood.

Anaerobic Methane Oxidation Driven by Microbial Reduction of Natural Organic Matter in a Tropical Wetland

PubMed Central

Valenzuela, Edgardo I.; Prieto-Davó, Alejandra; López-Lozano, Nguyen E.; Hernández-Eligio, Alberto; Vega-Alvarado, Leticia; Juárez, Katy; García-González, Ana Sarahí; López, Mercedes G.

2017-01-01

ABSTRACT Wetlands constitute the main natural source of methane on Earth due to their high content of natural organic matter (NOM), but key drivers, such as electron acceptors, supporting methanotrophic activities in these habitats are poorly understood. We performed anoxic incubations using freshly collected sediment, along with water samples harvested from a tropical wetland, amended with 13C-methane (0.67 atm) to test the capacity of its microbial community to perform anaerobic oxidation of methane (AOM) linked to the reduction of the humic fraction of its NOM. Collected evidence demonstrates that electron-accepting functional groups (e.g., quinones) present in NOM fueled AOM by serving as a terminal electron acceptor. Indeed, while sulfate reduction was the predominant process, accounting for up to 42.5% of the AOM activities, the microbial reduction of NOM concomitantly occurred. Furthermore, enrichment of wetland sediment with external NOM provided a complementary electron-accepting capacity, of which reduction accounted for ∼100 nmol 13CH4 oxidized · cm−3 · day−1. Spectroscopic evidence showed that quinone moieties were heterogeneously distributed in the wetland sediment, and their reduction occurred during the course of AOM. Moreover, an enrichment derived from wetland sediments performing AOM linked to NOM reduction stoichiometrically oxidized methane coupled to the reduction of the humic analogue anthraquinone-2,6-disulfonate. Microbial populations potentially involved in AOM coupled to microbial reduction of NOM were dominated by divergent biota from putative AOM-associated archaea. We estimate that this microbial process potentially contributes to the suppression of up to 114 teragrams (Tg) of CH4 · year−1 in coastal wetlands and more than 1,300 Tg · year−1, considering the global wetland area. IMPORTANCE The identification of key processes governing methane emissions from natural systems is of major importance considering the global warming effects triggered by this greenhouse gas. Anaerobic oxidation of methane (AOM) coupled to the microbial reduction of distinct electron acceptors plays a pivotal role in mitigating methane emissions from ecosystems. Given their high organic content, wetlands constitute the largest natural source of atmospheric methane. Nevertheless, processes controlling methane emissions in these environments are poorly understood. Here, we provide tracer analysis with 13CH4 and spectroscopic evidence revealing that AOM linked to the microbial reduction of redox functional groups in natural organic matter (NOM) prevails in a tropical wetland. We suggest that microbial reduction of NOM may largely contribute to the suppression of methane emissions from tropical wetlands. This is a novel avenue within the carbon cycle in which slowly decaying NOM (e.g., humic fraction) in organotrophic environments fuels AOM by serving as a terminal electron acceptor. PMID:28341676

Anaerobic Methane Oxidation Driven by Microbial Reduction of Natural Organic Matter in a Tropical Wetland.

PubMed

Valenzuela, Edgardo I; Prieto-Davó, Alejandra; López-Lozano, Nguyen E; Hernández-Eligio, Alberto; Vega-Alvarado, Leticia; Juárez, Katy; García-González, Ana Sarahí; López, Mercedes G; Cervantes, Francisco J

2017-06-01

Wetlands constitute the main natural source of methane on Earth due to their high content of natural organic matter (NOM), but key drivers, such as electron acceptors, supporting methanotrophic activities in these habitats are poorly understood. We performed anoxic incubations using freshly collected sediment, along with water samples harvested from a tropical wetland, amended with 13 C-methane (0.67 atm) to test the capacity of its microbial community to perform anaerobic oxidation of methane (AOM) linked to the reduction of the humic fraction of its NOM. Collected evidence demonstrates that electron-accepting functional groups (e.g., quinones) present in NOM fueled AOM by serving as a terminal electron acceptor. Indeed, while sulfate reduction was the predominant process, accounting for up to 42.5% of the AOM activities, the microbial reduction of NOM concomitantly occurred. Furthermore, enrichment of wetland sediment with external NOM provided a complementary electron-accepting capacity, of which reduction accounted for ∼100 nmol 13 CH 4 oxidized · cm -3 · day -1 Spectroscopic evidence showed that quinone moieties were heterogeneously distributed in the wetland sediment, and their reduction occurred during the course of AOM. Moreover, an enrichment derived from wetland sediments performing AOM linked to NOM reduction stoichiometrically oxidized methane coupled to the reduction of the humic analogue anthraquinone-2,6-disulfonate. Microbial populations potentially involved in AOM coupled to microbial reduction of NOM were dominated by divergent biota from putative AOM-associated archaea. We estimate that this microbial process potentially contributes to the suppression of up to 114 teragrams (Tg) of CH 4 · year -1 in coastal wetlands and more than 1,300 Tg · year -1 , considering the global wetland area. IMPORTANCE The identification of key processes governing methane emissions from natural systems is of major importance considering the global warming effects triggered by this greenhouse gas. Anaerobic oxidation of methane (AOM) coupled to the microbial reduction of distinct electron acceptors plays a pivotal role in mitigating methane emissions from ecosystems. Given their high organic content, wetlands constitute the largest natural source of atmospheric methane. Nevertheless, processes controlling methane emissions in these environments are poorly understood. Here, we provide tracer analysis with 13 CH 4 and spectroscopic evidence revealing that AOM linked to the microbial reduction of redox functional groups in natural organic matter (NOM) prevails in a tropical wetland. We suggest that microbial reduction of NOM may largely contribute to the suppression of methane emissions from tropical wetlands. This is a novel avenue within the carbon cycle in which slowly decaying NOM (e.g., humic fraction) in organotrophic environments fuels AOM by serving as a terminal electron acceptor. Copyright © 2017 American Society for Microbiology.

Methane oxidation in anoxic lake waters

NASA Astrophysics Data System (ADS)

Su, Guangyi; Zopfi, Jakob; Niemann, Helge; Lehmann, Moritz

2017-04-01

Freshwater habitats such as lakes are important sources of methante (CH4), however, most studies in lacustrine environments so far provided evidence for aerobic methane oxidation only, and little is known about the importance of anaerobic oxidation of CH4 (AOM) in anoxic lake waters. In marine environments, sulfate reduction coupled to AOM by archaea has been recognized as important sinks of CH4. More recently, the discorvery of anaerobic methane oxidizing denitrifying bacteria represents a novel and possible alternative AOM pathway, involving reactive nitrogen species (e.g., nitrate and nitrite) as electron acceptors in the absence of oxygen. We investigate anaerobic methane oxidation in the water column of two hydrochemically contrasting sites in Lake Lugano, Switzerland. The South Basin displays seasonal stratification, the development of a benthic nepheloid layer and anoxia during summer and fall. The North Basin is permanently stratified with anoxic conditions below 115m water depth. Both Basins accumulate seasonally (South Basin) or permanently (North Basin) large amounts of CH4 in the water column below the chemocline, providing ideal conditions for methanotrophic microorganisms. Previous work revealed a high potential for aerobic methane oxidation within the anoxic water column, but no evidence for true AOM. Here, we show depth distribution data of dissolved CH4, methane oxidation rates and nutrients at both sites. In addition, we performed high resolution phylogenetic analyses of microbial community structures and conducted radio-label incubation experiments with concentrated biomass from anoxic waters and potential alternative electron acceptor additions (nitrate, nitrite and sulfate). First results from the unamended experiments revealed maximum activity of methane oxidation below the redoxcline in both basins. While the incubation experiments neither provided clear evidence for NOx- nor sulfate-dependent AOM, the phylogenetic analysis revealed the presence of members of the Methylomirabiliaceae family (NC10 phylum), known to perform AOM with nitrite as terminal electron acceptor. Interestingly, albeit the similarly favorable conditions in both basins, the South Basin showed nearly two-fold higher CH4 oxidation rates, but the Methylomirabiliaceae abundance appeared to be much higher in the meromictic North Basin. Ongoing work will attempt to verify whether the apparent difference in the abundance of Methylomirabiliaceae is a permanent feature. We will further seek to determine the relative contribution of bacterial nitrite-dependent AOM to total methane oxidation, as well as the environmental controls that may explain the differential importance of Methylomirabiliaceae in the two connected lake basins.

The Geologic Signature of Anaerobic Oxidation of Methane (Invited)

NASA Astrophysics Data System (ADS)

Ussler, W.; Paull, C. K.

2010-12-01

Anaerobic oxidation of methane (AOM) is an enormous sink in anoxic marine sediments for methane produced in situ or ascending through the sediment column towards the seafloor. Existing estimates indicate that between 75 and 382 Tg of sedimentary methane are oxidized each year before reaching the sediment-water interface making AOM a diagenetic process of global significance. This methane is derived from a variety of sources including microbial production, thermocatalytic cracking of complex organic matter, decomposing gas hydrates, and possibly abiogenic processes. Stables isotopes of membrane lipid biomarkers and authigenic carbonates associated with zones of AOM, fluorescence in situ hybridization, and anaerobic methane incubations have substantiated the role Archaea and sulfate-reducing bacteria have in driving AOM. The products of AOM are dissolved inorganic carbon (predominantly HCO3-) and bisulfide (HS-). Stable isotope measurements of authigenic carbonates associated with zones of AOM are consistent with the diagenetic carbon being primarily methane derived. These methane-derived carbonates occur in a variety of forms including sedimentary nodules and thin lenses within and below zones of contemporary AOM; outcrops of slabs, ledges, and jagged authigenic carbonates exhumed on the seafloor; and authigenic carbonate mounds associated with near-subsurface methane gas accumulations. Examples of exhumed authigenic carbonates include rugged outcrops along the Guaymas Transform in the Gulf of California, extensive slabs and ledges in the Eel River Basin, and mounds in various stages of development near Bullseye Vent, off Vancouver Island and in the Santa Monica Basin. It is clear from basic microbial biogeochemistry and the occurrences of massive authigenic carbonate which span a large range in size that DIC produced by AOM is preserved as authigenic carbonate within the seafloor and not on the seafloor. These exhumed authigenic carbonate provide a glimpse of how authigenic carbonates may be appear in the geologic record. Based on the stochiometry of the AOM reaction [CH4 + SO4= → HCO3- + HS-], HCO3- and HS- should occur in a 1:1 molar ratio in sediment pore water. Methane-derived carbonates are common in methane-rich sediments and methane venting areas, however the corresponding amount of HS- precipitated as iron monosulfides (FeS) is not. The prediction, based on their molecular weights and densities, is that the volume ratio of authigenic carbonate to FeS should be 2:1. However, in anoxic Black Sea sediments, where a high degree of preservation would be expected, the authigenic carbonate to FeS ratio is ~50:1. Massive accumulations of FeS associated with authigenic carbonates have not been observed. There are a number of fates for the HS- produced by AOM: (1) HS- is oxidized in situ adding sulfate back to the pore water pool; (2) HS- selectively diffuses (relative to HCO3-) towards the seafloor and is oxidized in the benthic water column; or (3) FeS precipitates, but is oxidized when authigenic carbonates are exhumed leaving a vuggy texture. None of these explanations are entirely satisfactory for the early diagenetic loss of HS- from sediments, but strongly suggest that massive accumulations of FeS derived from AOM will not be found in the geologic record.

Antibiotics for acute otitis media in children.

PubMed

Venekamp, Roderick P; Sanders, Sharon; Glasziou, Paul P; Del Mar, Chris B; Rovers, Maroeska M

2013-01-31

Acute otitis media (AOM) is one of the most common diseases in early infancy and childhood. Antibiotic use for AOM varies from 56% in the Netherlands to 95% in the USA, Canada and Australia. To assess the effects of antibiotics for children with AOM. We searched CENTRAL (2012, Issue 10), MEDLINE (1966 to October week 4, 2012), OLDMEDLINE (1958 to 1965), EMBASE (January 1990 to November 2012), Current Contents (1966 to November 2012), CINAHL (2008 to November 2012) and LILACS (2008 to November 2012). Randomised controlled trials (RCTs) comparing 1) antimicrobial drugs with placebo and 2) immediate antibiotic treatment with expectant observation (including delayed antibiotic prescribing) in children with AOM. Two review authors independently assessed trial quality and extracted data. For the review of antibiotics against placebo, 12 RCTs (3317 children and 3854 AOM episodes) from high-income countries were eligible. However, one trial did not report patient-relevant outcomes, leaving 11 trials with generally low risk of bias. Pain was not reduced by antibiotics at 24 hours (risk ratio (RR) 0.89; 95% confidence interval (CI) 0.78 to 1.01) but almost a third fewer had residual pain at two to three days (RR 0.70; 95% CI 0.57 to 0.86; number needed to treat for an additional beneficial outcome (NNTB) 20) and fewer had pain at four to seven days (RR 0.79; 95% CI 0.66 to 0.95; NNTB 20). When compared with placebo, antibiotics did not alter the number of abnormal tympanometry findings at either four to six weeks (RR 0.92; 95% CI 0.83 to 1.01) or at three months (RR 0.97; 95% CI 0.76 to 1.24), or the number of AOM recurrences (RR 0.93; 95% CI 0.78 to 1.10). However, antibiotic treatment did lead to a statistically significant reduction of tympanic membrane perforations (RR 0.37; 95% CI 0.18 to 0.76; NNTB 33) and halved contralateral AOM episodes (RR 0.49; 95% CI 0.25 to 0.95; NNTB 11) as compared with placebo. Severe complications were rare and did not differ between children treated with antibiotics and those treated with placebo. Adverse events (such as vomiting, diarrhoea or rash) occurred more often in children taking antibiotics (RR 1.34; 95% CI 1.16 to 1.55; number needed to treat for an additional harmful outcome (NNTH) 14). Funnel plots do not suggest publication bias. Individual patient data meta-analysis of a subset of included trials found antibiotics to be most beneficial in children aged less than two with bilateral AOM, or with both AOM and otorrhoea.For the review of immediate antibiotics against expectant observation, five trials (1149 children) were eligible. Four trials (1007 children) reported outcome data that could be used for this review. From these trials, data from 959 children could be extracted for the meta-analysis on pain at days three to seven. No difference in pain was detectable at three to seven days (RR 0.75; 95% CI 0.50 to 1.12). No serious complications occurred in either the antibiotic group or the expectant observation group. Additionally, no difference in tympanic membrane perforations and AOM recurrence was observed. Immediate antibiotic prescribing was associated with a substantial increased risk of vomiting, diarrhoea or rash as compared with expectant observation (RR 1.71; 95% CI 1.24 to 2.36). Antibiotic treatment led to a statistically significant reduction of children with AOM experiencing pain at two to seven days compared with placebo but since most children (82%) settle spontaneously, about 20 children must be treated to prevent one suffering from ear pain at two to seven days. Additionally, antibiotic treatment led to a statistically significant reduction of tympanic membrane perforations (NNTB 33) and contralateral AOM episodes (NNTB 11). These benefits must be weighed against the possible harms: for every 14 children treated with antibiotics, one child experienced an adverse event (such as vomiting, diarrhoea or rash) that would not have occurred if antibiotics had been withheld. Antibiotics appear to be most useful in children under two years of age with bilateral AOM, or with both AOM and otorrhoea. For most other children with mild disease, an expectant observational approach seems justified. We have no trials in populations with higher risks of complications.

Exploring Ramsey-coherent population trapping atomic clock realized with pulsed microwave modulated laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Jing; Yun, Peter; Tian, Yuan

2014-03-07

A scheme for a Ramsey-coherent population trapping (CPT) atomic clock that eliminates the acousto-optic modulator (AOM) is proposed and experimentally studied. Driven by a periodically microwave modulated current, the vertical-cavity surface-emitting laser emits a continuous beam that switches between monochromatic and multichromatic modes. Ramsey-CPT interference has been studied with this mode-switching beam. In eliminating the AOM, which is used to generate pulsed laser in conventional Ramsey-CPT atomic clock, the physics package of the proposed scheme is virtually the same as that of a conventional compact CPT atomic clock, although the resource budget for the electronics will slightly increase as amore » microwave switch should be added. By evaluating and comparing experimentally recorded signals from the two Ramsey-CPT schemes, the short-term frequency stability of the proposed scheme was found to be 46% better than the scheme with AOM. The experimental results suggest that the implementation of a compact Ramsey-CPT atomic clock promises better frequency stability.« less

Ten Year Study of the Stringently Defined Otitis Prone Child in Rochester, NY

PubMed Central

Pichichero, Michael E.

2016-01-01

This review summarizes a prospective, longitudinal 10-year study in Rochester NY with virtually every clinically diagnosed acute otitis media (AOM) confirmed by bacterial culture of middle ear fluid. Children experiencing 3 episodes within 6 months or 4 episodes in 12 months were considered stringently-defined otitis prone (sOP). We found stringent diagnosis compared with clinical diagnosis reduced the frequency of children meeting the OP definition from 27% to 6% resulting in 14.8% and 2.4% receiving tympanostomy tubes, respectively. Significantly more often RSV infection led to AOM in sOP than non-otitis prone (NOP) children that correlated with diminished total RSV-specific serum IgG. sOP children produced low levels of antibody to Streptococcus pneumoniae and Haemophilus influenzae candidate vaccine protein antigens and to routine pediatric vaccines. sOP children generated significantly fewer memory B cells, functional and memory T cells to otopathogens following NP colonization and AOM than NOP children and they had defects in antigen presenting cells. PMID:27273691

Effect of neomycin on azoxymethane-induced colon carcinogenesis in F344 rats.

PubMed

Reddy, B S; Furuya, K; Lowenfels, A

1984-07-01

The effect of oral administration of neomycin (100 and 200 micrograms/ml in drinking water) on colon tumors induced by azoxymethane [(AOM); CAS: 25843-45-2] was studied in female F344 rats. Five-week-old rats were fed NIH-07 diet and given daily in drinking water 0, 100, and 200 micrograms neomycin/ml (0, 100, and 200 ppm). At 7 weeks of age, all animals except vehicle-treated groups received weekly sc injections of 8 mg AOM/kg body weight for 8 weeks. The AOM- or vehicle-treated groups were necropsied 30 weeks after the last injection of AOM. The combined incidence of adenomas and adenocarcinomas of the colon did not differ significantly among the 3 groups. The animals in the groups given 100 and 200 micrograms neomycin had a higher incidence of colon adenocarcinomas than did those in the control group. Colonic and cecal bacterial beta-glucuronidase activity was significantly lower in the group given 200 micrograms neomycin than it was in the control group. The excretion of fecal cholesterol, total bile acids, and deoxycholic acid was increased significantly in animals given 100 and 200 micrograms neomycin as compared to animals given no neomycin. These results suggest that long-term oral administration of neomycin increases the incidence of colon adenocarcinomas.

Cost-effectiveness analysis of routine pneumococcal vaccination in the UK: a comparison of the PHiD-CV vaccine and the PCV-13 vaccine using a Markov model.

PubMed

Delgleize, Emmanuelle; Leeuwenkamp, Oscar; Theodorou, Eleni; Van de Velde, Nicolas

2016-11-30

In 2010, the 13-valent pneumococcal conjugate vaccine (PCV-13) replaced the 7-valent vaccine (introduced in 2006) for vaccination against invasive pneumococcal diseases (IPDs), pneumonia and acute otitis media (AOM) in the UK. Using recent evidence on the impact of PCVs and epidemiological changes in the UK, we performed a cost-effectiveness analysis (CEA) to compare the pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) with PCV-13 in the ongoing national vaccination programme. CEA was based on a published Markov model. The base-case scenario accounted only for direct medical costs. Work days lost were considered in alternative scenarios. Calculations were based on serotype and disease-specific vaccine efficacies, serotype distributions and UK incidence rates and medical costs. Health benefits and costs related to IPD, pneumonia and AOM were accumulated over the lifetime of a UK birth cohort. Vaccination of infants at 2, 4 and 12 months with PHiD-CV or PCV-13, assuming complete coverage and adherence. The incremental cost-effectiveness ratio (ICER) was computed by dividing the difference in costs between the programmes by the difference in quality-adjusted life-years (QALY). Under our model assumptions, both vaccines had a similar impact on IPD and pneumonia, but PHiD-CV generated a greater reduction in AOM cases (161 918), AOM-related general practitioner consultations (31 070) and tympanostomy tube placements (2399). At price parity, PHiD-CV vaccination was dominant over PCV-13, saving 734 QALYs as well as £3.68 million to the National Health Service (NHS). At the lower list price of PHiD-CV, the cost-savings would increase to £45.77 million. This model projected that PHiD-CV would provide both incremental health benefits and cost-savings compared with PCV-13 at price parity. Using PHiD-CV could result in substantial budget savings to the NHS. These savings could be used to implement other life-saving interventions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Anaerobic methane oxidation in two tropical freshwater systems

NASA Astrophysics Data System (ADS)

Roland, Fleur; Darchambeau, François; Crowe, Sean A.; Borges, Alberto V.

2014-05-01

Lake Kivu is one of the East African Great Lakes. It is located at the border between Rwanda and the Democratic Republic of the Congo. It is a deep meromictic lake characterized by huge amounts of methane (CH4) (60 km3 at 0° C and 1 atm) dissolved in its deep waters. Two thirds of the CH4 originates from anoxic bacterial reduction of dissolved carbon dioxide and one third from anaerobic degradation of settling organic material. CH4 then diffuses slowly from the monimolimnion to surface waters where many is oxidised by methanotrophic microorganisms. In Lake Kivu, this biological oxidation of CH4 could occur with different final electron acceptors: oxygen (aerobic oxidation) but also nitrate (NO3-), nitrite, sulfate (SO42-), iron (Fe) or manganese (Mn) in anaerobic conditions. If the anaerobic oxidation of CH4 (AOM) is generally coupled to SO42- reduction in marine waters, electron acceptors of the AOM were rarely investigated in freshwater systems. Five field campaigns were conducted from 2011 to 2013 during periods with contrasted ventilations of the upper water column. The dry season is characterized by a deeper mixing of surface waters ended by a steep gradient of physico-chemical conditions at the redox interface, while during the rainy season the mixed layer is shallower and ended at its deeper part by a NO3- accumulation zone. Sampling was conducted in the main basin of Lake Kivu but also in a particular sub-basin located northeast of the lake, the Kabuno Bay. Both systems are meromictic but differ in terms of morphometry and geochemistry with a shallower permanent chemocline and higher concentrations of CH4, Fe and Mn in the anoxic waters in Kabuno Bay compared to the main lake. Samples were collected for the measurements of CH4 concentrations and the various potential electron acceptors of the AOM. CH4 oxidation rates were measured along vertical profiles at 5 m and 0.5 m depth intervals respectively in the main basin and Kabuno bay water columns. Results indicate high rates of AOM in both main basin (up to 7 μmol L-1 d-1) and Kabuno bay (up to 16 μmol L-1 d-1). In the main basin, we observed a co-occurrence of the AOM and the SO42- reduction in the dry season. During the rainy season, higher oxidation rates occurred in the NO3- accumulation zone, which is in favour of a coupling between AOM and NO3- reduction. In Kabuno Bay, the higher AOM rates were observed at depths with highest particulate Fe concentrations. Our results suggest that AOM coupled with SO42-reduction may occur during the dry season in the main basin, whereas this oxidation could be coupled with NO3- reduction during the rainy season. In Kabuno Bay, the co-occurrence of the Fe [III] peak with high AOM suggests a coupling between the AOM and Fe reduction.

Xylitol as a prophylaxis for acute otitis media: systematic review.

PubMed

Danhauer, Jeffrey L; Johnson, Carole E; Corbin, Nicole E; Bruccheri, Kaitlyn G

2010-10-01

A systematic review was conducted to evaluate evidence regarding xylitol, a sugar alcohol, as a prophylaxis for acute otitis media (AOM) in children. The authors searched PubMed and other databases to identify evidence. Criteria for included studies were: appear in English-language, peer-reviewed journals; at least quasi-experimental designs; use xylitol; and present outcome data. The authors completed evaluation forms for the included studies at all phases of the review. The authors reviewed 1479 titles and excluded 1435. Abstracts and full texts were reviewed for the remaining 44; four randomized controlled trials met inclusion criteria. Xylitol was a generally well accepted prophylaxis for AOM with few side effects when administered via chewing gum or syrup at 10 g/day given five times daily. Meta-analysis revealed significant treatment effects (Risk ratio = 0.68; 95% confidence interval = 0.57 to 0.83). Xylitol can be a prophylaxis for AOM, but warrants further study, especially of vehicles other than chewing gum for young children, and information is needed regarding cost, duration of administration required, and expected long-term effects.

Oral use of Streptococcus salivarius K12 in children with secretory otitis media: preliminary results of a pilot, uncontrolled study

PubMed Central

Di Pierro, Francesco; Di Pasquale, Daniele; Di Cicco, Maurizio

2015-01-01

Secretory otitis media (SOM) remains a common disease among children. Although its cause is not yet perfectly established, the pathology, often a sequel of acute otitis media (AOM), is mainly characterized by persistent fluid in the middle ear cavity. Twenty-two children with a diagnosis of SOM were treated daily for 90 days with an oral formulation containing the oral probiotic Streptococcus salivarius K12 (Bactoblis®). After treatment, the children were evaluated for AOM episodes and subjected to tone audiometry, tympanometry, endonasal endoscopy, otoscopy, and tonsillar examination. Subject compliance and probiotic tolerability and side effects have also been evaluated. Our results indicate a good safety profile, a substantial reduction of AOM episodes, and a positive outcome from the treatment for all of the clinical outcomes tested. We conclude that strain K12 may have a role in reducing the occurrence and/or severity of SOM in children. From our perspective, this study constitutes a starting point toward the organization of a more extensive placebo-controlled study aimed at critically appraising our preliminary observations. PMID:26396541

Zero-valent sulphur is a key intermediate in marine methane oxidation.

PubMed

Milucka, Jana; Ferdelman, Timothy G; Polerecky, Lubos; Franzke, Daniela; Wegener, Gunter; Schmid, Markus; Lieberwirth, Ingo; Wagner, Michael; Widdel, Friedrich; Kuypers, Marcel M M

2012-11-22

Emissions of methane, a potent greenhouse gas, from marine sediments are controlled by anaerobic oxidation of methane coupled primarily to sulphate reduction (AOM). Sulphate-coupled AOM is believed to be mediated by a consortium of methanotrophic archaea (ANME) and sulphate-reducing Deltaproteobacteria but the underlying mechanism has not yet been resolved. Here we show that zero-valent sulphur compounds (S(0)) are formed during AOM through a new pathway for dissimilatory sulphate reduction performed by the methanotrophic archaea. Hence, AOM might not be an obligate syntrophic process but may be carried out by the ANME alone. Furthermore, we show that the produced S(0)--in the form of disulphide--is disproportionated by the Deltaproteobacteria associated with the ANME. Our observations expand the diversity of known microbially mediated sulphur transformations and have significant implications for our understanding of the biogeochemical carbon and sulphur cycles.

Health and economic impact of PHiD-CV in Canada and the UK: a Markov modelling exercise.

PubMed

Knerer, Gerhart; Ismaila, Afisi; Pearce, David

2012-01-01

The spectrum of diseases caused by Streptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi) represents a large burden on healthcare systems around the world. Meningitis, bacteraemia, community-acquired pneumonia (CAP), and acute otitis media (AOM) are vaccine-preventable infectious diseases that can have severe consequences. The health economic model presented here is intended to estimate the clinical and economic impact of vaccinating birth cohorts in Canada and the UK with the 10-valent, pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) compared with the newly licensed 13-valent pneumococcal conjugate vaccine (PCV-13). The model described herein is a Markov cohort model built to simulate the epidemiological burden of pneumococcal- and NTHi-related diseases within birth cohorts in the UK and Canada. Base-case assumptions include estimates of vaccine efficacy and NTHi infection rates that are based on published literature. The model predicts that the two vaccines will provide a broadly similar impact on all-cause invasive disease and CAP under base-case assumptions. However, PHiD-CV is expected to provide a substantially greater reduction in AOM compared with PCV-13, offering additional savings of Canadian $9.0 million and £4.9 million in discounted direct medical costs in Canada and the UK, respectively. The main limitations of the study are the difficulties in modelling indirect vaccine effects (herd effect and serotype replacement), the absence of PHiD-CV- and PCV-13-specific efficacy data and a lack of comprehensive NTHi surveillance data. Additional limitations relate to the fact that the transmission dynamics of pneumococcal serotypes have not been modelled, nor has antibiotic resistance been accounted for in this paper. This cost-effectiveness analysis suggests that, in Canada and the UK, PHiD-CV's potential to protect against NTHi infections could provide a greater impact on overall disease burden than the additional serotypes contained in PCV-13.

A microbiome case-control study of recurrent acute otitis media identified potentially protective bacterial genera.

PubMed

Lappan, Rachael; Imbrogno, Kara; Sikazwe, Chisha; Anderson, Denise; Mok, Danny; Coates, Harvey; Vijayasekaran, Shyan; Bumbak, Paul; Blyth, Christopher C; Jamieson, Sarra E; Peacock, Christopher S

2018-02-20

Recurrent acute otitis media (rAOM, recurrent ear infection) is a common childhood disease caused by bacteria termed otopathogens, for which current treatments have limited effectiveness. Generic probiotic therapies have shown promise, but seem to lack specificity. We hypothesised that healthy children with no history of AOM carry protective commensal bacteria that could be translated into a specific probiotic therapy to break the cycle of re-infection. We characterised the nasopharyngeal microbiome of these children (controls) in comparison to children with rAOM (cases) to identify potentially protective bacteria. As some children with rAOM do not appear to carry any of the known otopathogens, we also hypothesised that characterisation of the middle ear microbiome could identify novel otopathogens, which may also guide the development of more effective therapies. Middle ear fluids, middle ear rinses and ear canal swabs from the cases and nasopharyngeal swabs from both groups underwent 16S rRNA gene sequencing. The nasopharyngeal microbiomes of cases and controls were distinct. We observed a significantly higher abundance of Corynebacterium and Dolosigranulum in the nasopharynx of controls. Alloiococcus, Staphylococcus and Turicella were abundant in the middle ear and ear canal of cases, but were uncommon in the nasopharynx of both groups. Gemella and Neisseria were characteristic of the case nasopharynx, but were not prevalent in the middle ear. Corynebacterium and Dolosigranulum are characteristic of a healthy nasopharyngeal microbiome. Alloiococcus, Staphylococcus and Turicella are possible novel otopathogens, though their rarity in the nasopharynx and prevalence in the ear canal means that their role as normal aural flora cannot be ruled out. Gemella and Neisseria are unlikely to be novel otopathogens as they do not appear to colonise the middle ear in children with rAOM.

Formation of carbonate pipes in the northern Okinawa Trough linked to strong sulfate exhaustion and iron supply

NASA Astrophysics Data System (ADS)

Peng, Xiaotong; Guo, Zixiao; Chen, Shun; Sun, Zhilei; Xu, Hengchao; Ta, Kaiwen; Zhang, Jianchao; Zhang, Lijuan; Li, Jiwei; Du, Mengran

2017-05-01

The microbial anaerobic oxidation of methane (AOM), a key biogeochemical process that consumes substantial amounts of methane produced in seafloor sediments, can lead to the formation of carbonate deposits at or beneath the sea floor. Although Fe oxide-driven AOM has been identified in cold seep sediments, the exact mode by which it may influence the formation of carbonate deposits remains poorly understood. Here, we characterize the morphology, petrology and geochemistry of a methane-derived Fe-rich carbonate pipe in the northern Okinawa Trough (OT). We detect abundant authigenic pyrites, as well as widespread trace Fe, within microbial mat-like carbonate veins in the pipe. The in situ δ34S values of these pyrites range from -3.9 to 31.6‰ (VCDT), suggesting a strong consumption of seawater sulfate by sulfate-driven AOM at the bottom of sulfate reduction zone. The positive δ56Fe values of pyrite and notable enrichment of Fe in the OT pipe concurrently indicate that the pyrites are primarily derived from Fe oxides in deep sediments. We propose that the Fe-rich carbonate pipe formed at the bottom of sulfate reduction zone, below which Fe-driven AOM, rather than Fe-oxide reduction coupled to organic matter degradation, might be responsible for the abundantly available Fe2+ in the fluids from which pyrites precipitated. The Fe-rich carbonate pipe described in this study probably represents the first fossil example of carbonate deposits linked to Fe-driven AOM. Because Fe-rich carbonate deposits have also been found at other cold seeps worldwide, we infer that similar processes may play an essential role in biogeochemical cycling of sub-seafloor methane and Fe at continental margins.

Weight loss following diet-induced obesity does not alter colon tumorigenesis in the AOM mouse model.

PubMed

Velázquez, Kandy T; Enos, Reilly T; Carson, Meredith S; Cranford, Taryn L; Bader, Jackie E; Chatzistamou, Ioulia; Singh, Udai P; Nagarkatti, Prakash S; Nagarkatti, Mitzi; Davis, J Mark; Carson, James A; Murphy, E Angela

2016-10-01

Obesity presents a significant public health concern given its association with increased cancer incidence, unfavorable prognosis, and metastasis. However, there is very little literature on the effects of weight loss, following obesity, on risk for colon cancer or liver cancer. Therefore, we sought to study whether intentional weight loss through diet manipulation was capable of mitigating colon and liver cancer in mice. We fed mice with a high-fat diet (HFD) comprised of 47% carbohydrates, 40% fat, and 13% protein for 20 wk to mimic human obesity. Subsequently, azoxymethane (AOM) was used to promote colon and liver carcinogenesis. A subset of obese mice was then switched to a low-fat diet (LFD) containing 67.5% carbohydrate, 12.2% fat, and 20% protein to promote intentional weight loss. Body weight loss and excess fat reduction did not protect mice from colon cancer progression and liver dysplastic lesion in the AOM-chemical-cancer model even though these mice had improved blood glucose and leptin levels. Intentional weight loss in AOM-treated mice actually produced histological changes that resemble dysplastic alterations in the liver and presented a higher percentage of F4/80 + CD206 + macrophages and activated T cells (CD4 + CD69 + ) in the spleen and lymph nodes, respectively. In addition, the liver of AOM-treated mice exposed to a HFD during the entire period of the experiment exhibited a marked increase in proliferation and pNF-κB activation. Altogether, these data suggest that intentional weight loss following chemical-induced carcinogenesis does not affect colon tumorigenesis but may in fact negatively impact liver repair mechanisms. Copyright © 2016 the American Physiological Society.

Acute otitis media guidelines in selected developed and developing countries: uniformity and diversity.

PubMed

Ovnat Tamir, Sharon; Shemesh, Shay; Oron, Yahav; Marom, Tal

2017-05-01

Acute otitis media (AOM) is a common childhood disease, with an enormous economic and healthcare-related burden. Guidelines and consensus papers for AOM diagnosis and management were published in many countries. Our objective was to study the differences and similarities between these protocols in developing and developed countries. The keywords: 'acute otitis media' AND 'children' AND ['treatment' or 'management'] AND ['guideline' or 'consensus'] were used in various electronic databases between 1 January 1989 through 31 December 2015. Overall, 99 sources from 62 countries were retrieved: 53 from 22 developed countries, and 46 from 40 developing countries. Representative guidelines from America (the USA, Argentina), Europe (Italy, Moldova), Africa (South Africa, Tanzania, Ethiopia), Asia (Japan, Afghanistan, Sri Lanka),and Oceania (South Australia, Fiji) were compared. Paediatric societies publish guidelines in most developed countries; in developing countries, the Ministry of Health usually initiates guideline formulation. Most guidelines use the same diagnostic criteria and offer watchful waiting in mild-moderate scenarios. Amoxicillin is the suggested first-line antibiotic, whereas options for second-line and third-line therapies vary. Duration of therapy varies and is usually age dependent: 5-7 days for children <2 years and 10 days for children >2 years in developed countries, while duration and age groups vary greatly in developing countries. Reduction of AOM risk factors is encouraged in developed countries, but rarely in developing countries. Guidelines for AOM from developing and developed countries are similar in many aspects, with variation in specific recommendations, due to local epidemiology and healthcare accessibility. Formulation of regional guidelines may help reduce AOM burden. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Implementation of UV-based advanced oxidation processes in algal medium recycling.

PubMed

Wang, Wenxuan; Sha, Jun; Lu, Zhiying; Shao, Senlin; Sun, Peizhe; Hu, Qiang; Zhang, Xuezhi

2018-09-01

Algae show great potential as sustainable feedstock for numerous bioproducts. However, large volume of water consumption during algal biomass production makes that the culture media recycling is a necessity due to economic and environmental concern. To avoid the negative effect of enriched organic matters in the harvested culture media, pre-treatment prior to medium replenishment and reuse is required. In this study, degradation of algenitic organic matters (AOM) in the culture media by UV-based photolysis processes (i.e., direct UV, UV/peroxydisulfate (PDS), UV/H 2 O 2 , and UV/NH 2 Cl) was explored. The results showed that UV, UV/PDS, UV/H 2 O 2 and UV/NH 2 Cl caused a decrease of SUVA for 29.9%, 35.4%, 40.45%, and 22.6%, respectively, though the organic matter was almost not mineralized. Fluorescence excitation-emission matrix combined with parallel factor analysis indicated that UV/PDS and UV/H 2 O 2 degraded 47.26%-56.31% of the fulvic-like and humic-like fractions in AOM. Powder activated carbon absorption and growth evaluation for the AOPs-treated media indicated that UV/PDS and UV/H 2 O 2 processes not only could remove the growth inhibitors in the media, but were also beneficial to the algae growth. These results suggested that UV/PDS and UV/H 2 O 2 could effectively degrade the hydrophobic components in AOM and converted the growth inhibition fraction of AOM in the recycled media into nutrient source for algal growth. Different from the general application of UV-based AOP in the wastewater treatment, this study provided an innovative idea about how to pre-treat AOM in the media recycling: utilization rather than removal, which was a more sustainable and environment-friendly technology. Copyright © 2018 Elsevier B.V. All rights reserved.

Anaerobic oxidation of methane associated with sulfate reduction in a natural freshwater gas source

PubMed Central

Timmers, Peer HA; Suarez-Zuluaga, Diego A; van Rossem, Minke; Diender, Martijn; Stams, Alfons JM; Plugge, Caroline M

2016-01-01

The occurrence of anaerobic oxidation of methane (AOM) and trace methane oxidation (TMO) was investigated in a freshwater natural gas source. Sediment samples were taken and analyzed for potential electron acceptors coupled to AOM. Long-term incubations with 13C-labeled CH4 (13CH4) and different electron acceptors showed that both AOM and TMO occurred. In most conditions, 13C-labeled CO2 (13CO2) simultaneously increased with methane formation, which is typical for TMO. In the presence of nitrate, neither methane formation nor methane oxidation occurred. Net AOM was measured only with sulfate as electron acceptor. Here, sulfide production occurred simultaneously with 13CO2 production and no methanogenesis occurred, excluding TMO as a possible source for 13CO2 production from 13CH4. Archaeal 16S rRNA gene analysis showed the highest presence of ANME-2a/b (ANaerobic MEthane oxidizing archaea) and AAA (AOM Associated Archaea) sequences in the incubations with methane and sulfate as compared with only methane addition. Higher abundance of ANME-2a/b in incubations with methane and sulfate as compared with only sulfate addition was shown by qPCR analysis. Bacterial 16S rRNA gene analysis showed the presence of sulfate-reducing bacteria belonging to SEEP-SRB1. This is the first report that explicitly shows that AOM is associated with sulfate reduction in an enrichment culture of ANME-2a/b and AAA methanotrophs and SEEP-SRB1 sulfate reducers from a low-saline environment. PMID:26636551

A Novel Modification of the AOM/DSS Model for Inducing Intestinal Adenomas in Mice.

PubMed

Angelou, Anastasios; Andreatos, Nikolaos; Antoniou, Efstathios; Zacharioudaki, Argiro; Theodoropoulos, George; Damaskos, Christos; Garmpis, Nikolaos; Yuan, Chunhui; Xiao, Weidong; Theocharis, Stamatios; Zografos, George; Papalois, Apostolos; Margonis, Georgios Antonios

2018-06-01

Our aim was to develop an animal model of the precancerous stages of colitis-associated carcinogenesis by modifying the established azoxymethane/dextran sulfate sodium (AOM/DSS) protocol. Six mice were treated with varying cycles of DSS following AOM administration as above (group 1: three mice received three 5-day cycles of 3.0% DSS and group 2: three mice received three 7-day cycles of 2.5% DSS; every cycle was followed by a 2-week rest period) and were sacrificed on day 84 of the experiment. By contrast, three female C57BL6 mice (group 3) were treated with a single intraperitoneal dose (10 mg/kg of body weight) of AOM followed by three 5-day cycles of oral 2.5% DSS, with each cycle interrupted by a 2-week rest period. The mice of this group were sacrificed at 60 days. In groups 1 and 2, cancer was noted in five out of the six mice. In group 3, adenomas with dysplastic lesions were noted in all of the mice, but none had developed adenocarcinoma. Our results suggest that the administration of three 5-day cycles of 2.5% DSS following an initial dose of AOM may successfully induce adenoma formation without the concurrent presence of carcinoma in female C57BL6 mice that are sacrificed on experimental day 60. In turn, this modification of the widely used AOM/DSS protocol may constitute a novel approach for investigating colitis-related colonic adenomas. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Towards quantifying the reaction network around the sulfate–methane-transition-zone in the Ulleung Basin, East Sea, with a kinetic modeling approach

DOE PAGES

Hong, Wei-Li; Torres, Marta E.; Kim, Ji-Hoon; ...

2014-09-01

We present a kinetic model based upon pore water data collected from eight sites drilled during the second Ulleung Basin gas hydrate drilling expedition (UBGH2) in 2010. Three sites were drilled at locations where acoustic chimneys were identified in seismic data, and the rest were drilled on non-chimney (i.e. background) environments. Our model, coupled a comprehensive compositional and isotopic data set, is used to illustrate the different biogeochemical processes at play in those two environments, in terms of reactions around the sulfate-methane-transition-zone (SMTZ). Organic matter decomposition is an important process for production of methane, dissolved inorganic carbon (DIC) and consumptionmore » of sulfate in the non-chimney sites, whereas anaerobic oxidation of methane (AOM) dominates both carbon and sulfur cycles in the chimney environment. Different sources of methane mediate AOM in the two settings. Internally produced methane through CO₂ reduction (CR) and methanogenesis fuels AOM in the non-chimney sites, whereas AOM is sustained by methane from external sources in the chimney sites. We also simulate the system evolution from non-chimney to chimney conditions by increasing the bottom methane supply to a non-chimney setting. We show that the higher CH₄ flux leads to a higher microbial activity of AOM, and more organic matter decomposition through methanogenesis. A higher methanogenesis rate and a smaller CR contribution relative to AOM in the chimney sites is responsible for the isotopically light DIC and heavy methane in this environment, relative to the non-chimney sites.« less

The Incidence, Prevalence and Burden of OM in Unselected Children Aged 1 to 8 Years Followed by Weekly Otoscopy through the “Common Cold” Season

PubMed Central

Mandel, Ellen M.; Doyle, William J.; Winther, Birgit; Alper, Cuneyt M.

2008-01-01

Background There is a continuing interest in defining the incidence, prevalence and burden of otitis media (OM) in the individual and population for purposes of assigning “risk factors”. Often overlooked in past studies are the contributions of cold-like illnesses (CLIs) and sampling interval to those estimates. Objective Describe the incidence of symptomatic (AOM) and asymptomatic (OME) OM, the prevalence of OM, the contribution of CLI incidence, burden and other OM “risk factors” to the incidence and burden of OM, and the effect of sampling interval on those measures in children. Methods 148 children (74 male; 131 white, aged 1.0–8.6 years) were followed from November 1 to April 30 by weekly pneumatic otoscopy to diagnose OM presence/absence and by daily parental diary to assign CLI episodes. Data for previously identified OM “risk factors” were collected on 127. Results were summarized using standard measures of incidence, prevalence and burden, and multiple-regression techniques were used to identify OM “risk factors”. Results The basal OM prevalence was 20% with peaks in December and March and the temporal pattern was correlated with CLI prevalence. The incidence of OME (per 27232 child-days) was 317, AOM was 74 and CLI was 456. The seasonal pattern of AOM and OME incidences tracked and was correlated with that for CLIs. New OM episodes were usually of short duration (≤7 days in 40%, ≤4 weeks in 75–90%) and the usual OM burden was low (median=12%). OM and breastfeeding histories and CLI incidence/prevalence were significant predictors of OME and AOM incidence and OM burden. Longer sampling intervals were less efficient in capturing AOM and OME durations and incidences, but not OM burden. Conclusions These results demonstrate a high incidence and prevalence of OM, most OM episodes were of short duration and longer sampling intervals introduced biases into some parameter estimates. There was a significant relationship between OM and CLI incidence, prevalence and burden suggesting that CLI experience should be controlled for in assessing independent “risk factors” for AOM and OME. PMID:18272237

Methane Seep in Shallow-Water Permeable Sediment Harbors High Diversity of Anaerobic Methanotrophic Communities, Elba, Italy

PubMed Central

Ruff, S. Emil; Kuhfuss, Hanna; Wegener, Gunter; Lott, Christian; Ramette, Alban; Wiedling, Johanna; Knittel, Katrin; Weber, Miriam

2016-01-01

The anaerobic oxidation of methane (AOM) is a key biogeochemical process regulating methane emission from marine sediments into the hydrosphere. AOM is largely mediated by consortia of anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB), and has mainly been investigated in deep-sea sediments. Here we studied methane seepage at four spots located at 12 m water depth in coastal, organic carbon depleted permeable sands off the Island of Elba (Italy). We combined biogeochemical measurements, sequencing-based community analyses and in situ hybridization to investigate the microbial communities of this environment. Increased alkalinity, formation of free sulfide and nearly stoichiometric methane oxidation and sulfate reduction rates up to 200 nmol g-1 day-1 indicated the predominance of sulfate-coupled AOM. With up to 40 cm thickness the zones of AOM activity were unusually large and occurred in deeper sediment horizons (20–50 cm below seafloor) as compared to diffusion-dominated deep-sea seeps, which is likely caused by advective flow of pore water due to the shallow water depth and permeability of the sands. Hydrodynamic forces also may be responsible for the substantial phylogenetic and unprecedented morphological diversity of AOM consortia inhabiting these sands, including the clades ANME-1a/b, ANME-2a/b/c, ANME-3, and their partner bacteria SEEP-SRB1a and SEEP-SRB2. High microbial dispersal, the availability of diverse energy sources and high habitat heterogeneity might explain that the emission spots shared few microbial taxa, despite their physical proximity. Although the biogeochemistry of this shallow methane seep was very different to that of deep-sea seeps, their key functional taxa were very closely related, which supports the global dispersal of key taxa and underlines strong selection by methane as the predominant energy source. Mesophilic, methane-fueled ecosystems in shallow-water permeable sediments may comprise distinct microbial habitats due to their unique biogeochemical and physical characteristics. To link AOM phylotypes with seep habitats and to enable future meta-analyses we thus propose that seep environment ontology needs to be further specified. PMID:27065954

Methane Seep in Shallow-Water Permeable Sediment Harbors High Diversity of Anaerobic Methanotrophic Communities, Elba, Italy.

PubMed

Ruff, S Emil; Kuhfuss, Hanna; Wegener, Gunter; Lott, Christian; Ramette, Alban; Wiedling, Johanna; Knittel, Katrin; Weber, Miriam

2016-01-01

The anaerobic oxidation of methane (AOM) is a key biogeochemical process regulating methane emission from marine sediments into the hydrosphere. AOM is largely mediated by consortia of anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB), and has mainly been investigated in deep-sea sediments. Here we studied methane seepage at four spots located at 12 m water depth in coastal, organic carbon depleted permeable sands off the Island of Elba (Italy). We combined biogeochemical measurements, sequencing-based community analyses and in situ hybridization to investigate the microbial communities of this environment. Increased alkalinity, formation of free sulfide and nearly stoichiometric methane oxidation and sulfate reduction rates up to 200 nmol g(-1) day(-1) indicated the predominance of sulfate-coupled AOM. With up to 40 cm thickness the zones of AOM activity were unusually large and occurred in deeper sediment horizons (20-50 cm below seafloor) as compared to diffusion-dominated deep-sea seeps, which is likely caused by advective flow of pore water due to the shallow water depth and permeability of the sands. Hydrodynamic forces also may be responsible for the substantial phylogenetic and unprecedented morphological diversity of AOM consortia inhabiting these sands, including the clades ANME-1a/b, ANME-2a/b/c, ANME-3, and their partner bacteria SEEP-SRB1a and SEEP-SRB2. High microbial dispersal, the availability of diverse energy sources and high habitat heterogeneity might explain that the emission spots shared few microbial taxa, despite their physical proximity. Although the biogeochemistry of this shallow methane seep was very different to that of deep-sea seeps, their key functional taxa were very closely related, which supports the global dispersal of key taxa and underlines strong selection by methane as the predominant energy source. Mesophilic, methane-fueled ecosystems in shallow-water permeable sediments may comprise distinct microbial habitats due to their unique biogeochemical and physical characteristics. To link AOM phylotypes with seep habitats and to enable future meta-analyses we thus propose that seep environment ontology needs to be further specified.

Methane emission and consumption at a North Sea gas seep (Tommeliten area)

NASA Astrophysics Data System (ADS)

Niemann, H.; Elvert, M.; Hovland, M.; Orcutt, B.; Judd, A.; Suck, I.; Gutt, J.; Joye, S.; Damm, E.; Finster, K.; Boetius, A.

The Tommeliten seepage area is part of the Greater Ekofisk area, which is situated above the Tommeliten Delta salt diapir in the central North Sea (56°29.90' N, 2°59.80' E, Norwegian Block 1/9, 75 m water depth). Here, cracks in a buried marl horizon allow methane to migrate into overlying clay-silt and sandy sediments. Hydroacoustic sediment echosounding showed several venting spots coinciding with the apex of marl domes where methane is released into the water column and potentially to the atmosphere. In the vicinity of the gas seeps, sea floor observations showed small mats of giant sulphide-oxidizing bacteria above patches of black sediments as well as carbonate crusts, which are exposed 10 to 50 cm above seafloor forming small reefs. These Methane-Derived Authigenic Carbonates (MDACs) contain 13C-depleted, archaeal lipids indicating previous gas seepage and AOM activity. High amounts of sn2-hydroxyarchaeol relative to archaeol and low abundances of biphytanes in the crusts give evidence that ANaerobic MEthane-oxidising archaea (ANME) of the phylogenetic cluster ANME-2 were the potential mediators of Anaerobic Oxidation of Methane (AOM) at the time of carbonate formation. Small pieces of MDACs were also found subsurface at about 1.7 m sediment depth, associated with the AOM zone. This zone is characterized by elevated AOM and Sulphate Reduction (SR) rates, increased concentrations of 13C-depleted tetraether derived biphytanes, and specific bacterial Fatty Acids (FA). Further biomarker and 16S rDNA based analyses of this horizon give evidence that AOM is mediated by archaea belonging to the ANME-1b group and Sulphate Reducing Bacteria (SRB) most likely belonging to the Seep-SRB1 cluster. The zone of active methane consumption was restricted to a distinct horizon of about 20 cm. Concentrations of 13C-depleted lipid biomarkers (e.g. 500 ng g-dw-1 biphythanes, 140 ng g-dw-1 fatty acid ai-C15:0), cell numbers (1.5×108 cells cm-3), AOM and SR rates (3 nmol cm-3 d-1) in the Tommeliten AOM zone are 2 3 orders of magnitude lower compared to AOM zones of highly active deep water cold seeps such as Hydrate Ridge or the Gulf of Mexico.

Endoscopic and clinical benefits of hyaluronic acid in children with chronic adenoiditis and middle ear disease.

PubMed

Torretta, S; Marchisio, P; Rinaldi, V; Carioli, D; Nazzari, E; Pignataro, L

2017-03-01

Hyaluronic acid (HA) is involved in modulating inflammatory airway processes and mucociliary clearance. Some studies have tested the effectiveness of the topical administration of HA in patients with upper airway diseases with positive preliminary results. A prospective, single-blind, 1:1 randomised controlled study was performed to assess the efficacy and safety of the daily topical administration of 9 mg of sodium hyaluronate in 3 mL of a 0.9 % sodium saline solution on the basis of endoscopic and clinical parameters in children with chronic adenoiditis associated with recurrent acute otitis media and otitis media with effusion; age- and gender-matched children receiving normal 0.9 % sodium chloride saline solution were used as controls. Analysis was based on 103 (mean age 63.3 ± 18.2 months; 52 males, 50.5 %) children: 54 in the study group and 49 in the control group. A statistically significant reduction in the mean number of all acute otitis media episodes (AOME) (mean reduction 0.8 ± 0.4 per month; p value 0.05) and AOME without tympanic membrane perforation (mean reduction 0.6 ± 0.3 per month; p value 0.04) after recruitment was documented only in the study group. HA significantly improved all the endoscopic outcomes (p values ranging between 0.05 and <0.01) but one. Nasal washing with saline solution was effective on only three of them (p values ranging between 0.03 and <0.01). No untoward effects were documented. Our results confirm the safety and document the positive effect of topically administered HA solution on children with chronic adenoiditis associated with middle ear disease.

Burden of acute otitis media on Canadian families

PubMed Central

Dubé, Eve; De Wals, Philippe; Gilca, Vladimir; Boulianne, Nicole; Ouakki, Manale; Lavoie, France; Bradet, Richard

2011-01-01

Abstract Objective To estimate the burden of acute otitis media (AOM) on Canadian families. Design Telephone survey using random-digit dialing. Setting All Canadian provinces between May and June 2008. Participants Caregivers of 1 or more children aged 6 months to 5 years. Main outcome measures Caregivers’ reports on the number of AOM episodes experienced by the child in the past 12 months, as well as disease characteristics, health services and medication use, time spent on medical consultations (including travel), and time taken off from work to care for the sick children. Results A total of 502 eligible caregivers were recruited, 161 (32%) of whom reported at least 1 AOM episode for their children and 42 (8%) of whom reported 3 or more episodes during the past 12 months. Most children (94%, 151 of 161) visited with health professionals during their most recent AOM episodes. The average time required for medical examination was 3.1 hours in an emergency department and 1.8 hours in an outpatient clinic. Overall, 93% of episodes resulted in antibiotics use. A substantial proportion of caregivers (38%) missed work during this time; the average time taken off work was 15.9 hours. Conclusion In Canada, episodes of AOM are still associated with substantial use of health services and indirect costs to the caregivers. PMID:21252135

Performance of titanium salts compared to conventional FeCl3 for the removal of algal organic matter (AOM) in synthetic seawater: Coagulation performance, organic fraction removal and floc characteristics.

PubMed

Chekli, L; Corjon, E; Tabatabai, S A A; Naidu, G; Tamburic, B; Park, S H; Shon, H K

2017-10-01

During algal bloom periods, operation of seawater reverse osmosis (SWRO) pretreatment processes (e.g. ultrafiltration (UF)) has been hindered due to the high concentration of algal cells and algal organic matter (AOM). The present study evaluated for the first time the performance of titanium salts (i.e. titanium tetrachloride (TiCl 4 ) and polytitanium tetrachloride (PTC)) for the removal of AOM in seawater and results were compared with the conventional FeCl 3 coagulant. Previous studies already demonstrated that titanium salts not only provide a cost-effective alternative to conventional coagulants by producing a valuable by-product but also minimise the environmental impact of sludge production. Results from this study showed that both TiCl 4 and PTC achieved better performance than FeCl 3 in terms of turbidity, UV 254 and dissolved organic carbon (DOC) removal at similar coagulant dose. Liquid chromatography - organic carbon detection (LC-OCD) was used to determine the removal of AOM compounds based on their molecular weight (MW). This investigation revealed that both humic substances and low MW organics were preferentially removed (i.e. up to 93% removal) while all three coagulants showed poorer performance for the removal of high MW biopolymers (i.e. less than 50% removal). The detailed characterization of flocs indicated that both titanium coagulants can grow faster, reach larger size and present a more compact structure, which is highly advantageous for the design of smaller and more compact mixing and sedimentation tanks. Both titanium coagulants also presented a higher ability to withstand shear force, which was related to the higher amount of DOC adsorbed with the aggregated flocs. Finally, TiCl 4 had a better recovery after breakage suggesting that charge neutralization may be the dominant mechanism for this coagulant, while the lower recovery of both PTC and FeCl 3 indicated that sweep flocculation is also a contributing mechanism for the coagulation of AOM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Colonic aberrant crypt formation accompanies an increase of opportunistic pathogenic bacteria in C57BL/6 mice fed a high-fat diet.

PubMed

Zeng, Huawei; Ishaq, Suzanne L; Liu, Zhenhua; Bukowski, Michael R

2018-04-01

The increasing worldwide incidence of colon cancer has been linked to obesity and consumption of a high-fat Western diet. To test the hypothesis that a high-fat diet (HFD) promotes colonic aberrant crypt (AC) formation in a manner associated with gut bacterial dysbiosis, we examined the susceptibility to azoxymethane (AOM)-induced colonic AC and microbiome composition in C57/BL6 mice fed a modified AIN93G diet (AIN, 16% fat, energy) or an HFD (45% fat, energy) for 14 weeks. Mice receiving the HFD exhibited increased plasma leptin, body weight, body fat composition and inflammatory cell infiltration in the ileum compared with those in the AIN group. Consistent with the gut inflammatory phenotype, we observed an increase in colonic AC, plasma interleukin-6, tumor necrosis factor-α, monocyte chemoattractant protein-1 and inducible nitric oxide synthase in the ileum of the HFD-AOM group compared with the AIN-AOM group. Although the HFD and AIN groups did not differ in bacterial species number, the HFD and AIN diets resulted in different bacterial community structures in the colon. The abundance of certain short-chain fatty acid (SCFA) producing bacteria (e.g., Barnesiella) and fecal SCFA (e.g., acetic acid) content were lower in the HFD-AOM group compared with the AIN and AIN-AOM groups. Furthermore, we identified a high abundance of Anaeroplasma bacteria, an opportunistic pathogen in the HFD-AOM group. Collectively, we demonstrate that an HFD promotes AC formation concurrent with an increase of opportunistic pathogenic bacteria in the colon of C57BL/6 mice. Published by Elsevier Inc.

Serum antibody response to Moraxella catarrhalis proteins in stringently defined otitis prone children.

PubMed

Ren, Dabin; Almudevar, Anthony L; Murphy, Timothy F; Lafontaine, Eric R; Campagnari, Anthony A; Luke-Marshall, Nicole; Pichichero, Michael E

2017-07-26

Moraxella catarrhalis (Mcat) is a frequent pathogen of acute otitis media (AOM) in young children. Here we prospectively assessed naturally-induced serum antibodies to four Mcat vaccine candidate proteins in stringently defined otitis prone (sOP) and non-otitis prone (NOP) children age 6-36months old following nasopharyngeal (NP) colonization, at onset of AOM and convalescence from AOM. Serum IgG and IgM antibody against recombinant Mcat proteins, oligopeptide permease A (OppA), outer membrane protein (OMP) CD, hemagglutinin (Hag), and PilA clade 2 (PilA2), were quantitated by ELISA. During NP colonization by Mcat all four antigens were immunogenic in both sOP and NOP children. However, sOP children had lower antibody responses than NOP children across age 6-36months, similar to our findings for protein vaccine candidates of Streptococcus pneumoniae (Spn) and Nontypeable Haemophilus influenzae (NTHi). sOP children displayed a later and lower peak of antibody rise than NOP children for all four antigens during NP colonization of Mcat. The age-dependent increase of antibody ranked as OppA>Hag5-9>OMP CD>PilA2 in both sOP and NOP children. Lower serum antibody levels to the Mcat antigens were measured in sOP compared to NOP children at the onset of AOM. We did not find a consistent significant increase of antibody at the convalescence phase after an AOM event. sOP children is a highly vulnerable population that mount lower serum antibody responses to Mcat candidate vaccine proteins compared to NOP children during asymptomatic NP carriage and at onset of AOM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Symptomatic and asymptomatic respiratory viral infections in the first year of life: association with acute otitis media development.

PubMed

Chonmaitree, Tasnee; Alvarez-Fernandez, Pedro; Jennings, Kristofer; Trujillo, Rocio; Marom, Tal; Loeffelholz, Michael J; Miller, Aaron L; McCormick, David P; Patel, Janak A; Pyles, Richard B

2015-01-01

Sensitive diagnostic assays have increased the detection of viruses in asymptomatic individuals. The clinical significance of asymptomatic respiratory viral infection in infants is unknown. High-throughput, quantitative polymerase chain reaction assays were used to detect 13 common respiratory viruses from nasopharyngeal specimens collected during 2028 visits from 362 infants followed from near birth up to 12 months of age. Specimens were collected at monthly interval (months 1-6 and month 9) and during upper respiratory tract infection (URTI) episodes. Subjects were followed closely for acute otitis media (AOM) development. Viruses were detected in 76% of 394 URTI specimens and 27% of asymptomatic monthly specimens. Rhinovirus was detected most often; multiple viruses were detected in 29% of the specimens. Generalized mixed-model analyses associated symptoms with increasing age and female sex; detection of respiratory syncytial virus (RSV), influenza, rhinovirus, metapneumovirus, and adenovirus was highly associated with symptoms. Increasing age was also associated with multiple virus detection. Overall, 403 asymptomatic viral infections in 237 infants were identified. Viral load was significantly higher in URTI specimens than asymptomatic specimens but did not differentiate cases of URTI with and without AOM complication. The rate of AOM complicating URTI was 27%; no AOM occurred following asymptomatic viral infections. AOM development was associated with increasing age and infection with RSV, rhinovirus, enterovirus, adenovirus, and bocavirus. Compared to symptomatic infection, asymptomatic viral infection in infants is associated with young age, male sex, low viral load, specific viruses, and single virus detection. Asymptomatic viral infection did not result in AOM. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Xylitol Syrup for the Prevention of Acute Otitis Media

PubMed Central

Corwin, Michael J.; Vezina, Richard M.; Pelton, Steven I.; Feldman, Henry A.; Coyne-Beasley, Tamera; Mitchell, Allen A.

2014-01-01

BACKGROUND: Acute otitis media (AOM) is a common childhood illness and the leading indication for antibiotic prescriptions for US children. Xylitol, a naturally occurring sugar alcohol, can reduce AOM when given 5 times per day as a gum or syrup, but a more convenient dosing regimen is needed for widespread adoption. METHODS: We designed a pragmatic practice-based randomized controlled trial to determine if viscous xylitol solution at a dose of 5 g 3 times per day could reduce the occurrence of clinically diagnosed AOM among otitis-prone children 6 months through 5 years of age. RESULTS: A total of 326 subjects were enrolled, with 160 allocated to xylitol and 166 to placebo. In the primary analysis of time to first clinically diagnosed AOM episode, the hazard ratio for xylitol versus placebo recipients was 0.88 (95% confidence interval [CI] 0.61 to 1.3). In secondary analyses, the incidence of AOM was 0.53 episodes per 90 days in the xylitol group versus 0.59 in the placebo group (difference 0.06; 95% CI –0.25 to 0.13); total antibiotic use was 6.8 days per 90 days in the xylitol group versus 6.4 in the placebo group (difference 0.4; 95% CI –1.8 to 2.7). The lack of effectiveness was not explained by nonadherence to treatment, as the hazard ratio for those taking nearly all assigned xylitol compared with those taking none was 0.93 (95% CI 0.56 to 1.57). CONCLUSIONS: Viscous xylitol solution in a dose of 5 g 3 times per day was ineffective in reducing clinically diagnosed AOM among otitis-prone children. PMID:24394686

Ultraviolet A eye irradiation ameliorates colon carcinoma induced by azoxymethane and dextran sodium sulfate through β-endorphin and methionine-enkephalin.

PubMed

Hiramoto, Keiichi; Yokoyama, Satoshi; Yamate, Yurika

2017-03-01

We previously reported that ultraviolet (UV) A eye irradiation reduces the ulcerative colitis induced by dextran sodium sulfate (DSS). This study examined the effects of UVA on colon carcinoma induced by azoxymethane (AOM) and DSS. We irradiated the eyes of ICR mice with UVA at a dose of 110 kJ/m 2 using an FL20SBLB-A lamp for the experimental period. In mice treated with these drugs, the symptom of colon carcinoma was reduced by UVA eye irradiation. The levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the blood were increased in AOM + DSS-treated mice; however, those levels were reduced by UVA eye irradiation. The expression of β-endorphin, methionine-enkephalin (OGF), μ-opioid receptor, and opioid growth factor receptor (OGFR) of the colon was increased in the AOM + DSS-treated mice, and these levels were increased further following UVA eye irradiation. When β-endorphin inhibitor was administered, the ameliorative effect of UVA eye irradiation was reduced, and the effect of eye irradiation disappeared entirely following the administration of naltrexone (inhibitor of both opioid receptor and OGFR). These results suggested that UVA eye irradiation exerts major effects on AOM + DSS-induced colon carcinoma. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Reverse Methanogenesis and Respiration in Methanotrophic Archaea

PubMed Central

Koehorst, Jasper J.; Jetten, Mike S. M.; Stams, Alfons J. M.

2017-01-01

Anaerobic oxidation of methane (AOM) is catalyzed by anaerobic methane-oxidizing archaea (ANME) via a reverse and modified methanogenesis pathway. Methanogens can also reverse the methanogenesis pathway to oxidize methane, but only during net methane production (i.e., “trace methane oxidation”). In turn, ANME can produce methane, but only during net methane oxidation (i.e., enzymatic back flux). Net AOM is exergonic when coupled to an external electron acceptor such as sulfate (ANME-1, ANME-2abc, and ANME-3), nitrate (ANME-2d), or metal (oxides). In this review, the reversibility of the methanogenesis pathway and essential differences between ANME and methanogens are described by combining published information with domain based (meta)genome comparison of archaeal methanotrophs and selected archaea. These differences include abundances and special structure of methyl coenzyme M reductase and of multiheme cytochromes and the presence of menaquinones or methanophenazines. ANME-2a and ANME-2d can use electron acceptors other than sulfate or nitrate for AOM, respectively. Environmental studies suggest that ANME-2d are also involved in sulfate-dependent AOM. ANME-1 seem to use a different mechanism for disposal of electrons and possibly are less versatile in electron acceptors use than ANME-2. Future research will shed light on the molecular basis of reversal of the methanogenic pathway and electron transfer in different ANME types. PMID:28154498

Membrane lipid patterns typify distinct anaerobic methanotrophic consortia

PubMed Central

Blumenberg, Martin; Seifert, Richard; Reitner, Joachim; Pape, Thomas; Michaelis, Walter

2004-01-01

The anaerobic oxidation of methane (AOM) is one of the major sinks of this substantial greenhouse gas in marine environments. Recent investigations have shown that diverse communities of anaerobic archaea and sulfate-reducing bacteria are involved in AOM. Most of the relevant archaea are assigned to two distinct phylogenetic clusters, ANME-1 and ANME-2. A suite of specific 13C-depleted lipids demonstrating the presence of consortia mediating AOM in fossil and recent environments has been established. Here we report on substantial differences in the lipid composition of microbial consortia sampled from distinct compartments of AOM-driven carbonate reefs growing in the northwestern Black Sea. Communities in which the dominant archaea are from the ANME-1 cluster yield internally cyclized tetraether lipids typical of thermophiles. Those in which ANME-2 archaea are dominant yield sn-2-hydroxyarchaeol accompanied by crocetane and crocetenes. The bacterial lipids from these communities are also distinct even though the sulfate-reducing bacteria all belong to the Desulfosarcina/Desulfococcus group. Nonisoprenoidal glycerol diethers are predominantly associated with ANME-1-dominated communities. Communities with ANME-2 yield mainly conventional, ester-linked diglycerides. ANME-1 archaea and associated sulfate-reducing bacteria seem to be enabled to use low concentrations of methane and to grow within a broad range of temperatures. Our results offer a tool for the study of recent and especially of fossil methane environments. PMID:15258285

Does senna extract promote growth of aberrant crypt foci and malignant tumors in rat colon?

PubMed

Mascolo, N; Mereto, E; Borrelli, F; Orsi, P; Sini, D; Izzo, A A; Massa, B; Boggio, M; Capasso, F

1999-11-01

Current evidence suggests that aberrant crypt foci (ACF) can be used to evaluate agents for their potential colon carcinogenic activity. The aim of the present study was to determine whether senna pod extract (SE) itself induces ACF and tumors in the rat colon or increases the development of ACF and tumors induced by azoxymethane (AOM). A daily administration of SE 10 mg/kg by mouth for 13-28 weeks produced a weak laxative effect but did not itself cause the appearance of ACF or tumors. The numbers of ACF and tumors induced by AOM were, however, increased by a dose of SE (100 mg/kg) able to induce chronic diarrhea over three months. These results suggest that SE does not cause the appearance of ACF or tumors in the rat colon nor does it have a promoting effect when given to rats at a dose that produces laxation (10 mg/kg), whereas a diarrhogenic dose (100 mg/kg) increases the appearance of tumors induced by AOM.

Healthcare-seeking behaviour of primary caregivers for acute otitis media in children aged 6 months to <30 months in Panama: results of a cross-sectional survey.

PubMed

Villarreal, Iris; Turner, Rosario; Jo, Hyejin; Park, Julie; Gemmen, Eric; Pirçon, Jean-Yves; Castrejon, Maria M; Hausdorff, William P

2017-01-05

Acute otitis media (AOM) is the most common bacterial childhood infection. However, caregivers with children having mild episodes often do not seek healthcare services, which may lead to an under-appreciation of the disease experienced by the community. The objectives of this survey were to estimate the proportion of primary caregivers who went to a healthcare facility when they suspected that their child aged 6 to <30 months was having an AOM episode during the past 6 months and to assess what factors influenced their decision. This observational, cross-sectional survey of primary caregivers (≥18 years), with at least one child aged 6 to <30 months was performed in 19 healthcare facilities in Panama (March to May 2013). A 28-item paper questionnaire was administered to assess demographic data, AOM symptoms, as well as potential healthcare-seeking behaviour and factors influencing this behaviour. Potential confounding effects were individually assessed using Chi-squared or Cochran-Mantel-Haenszel tests, and all together in logistic regression models. The total number of eligible participants was 1330 (mean age 28.5 ± 8.0 years). Of these, 245 participants had at least one child whom they suspected had an AOM episode during the past 6 months. Of the 245 participants, 213 (86.9%) sought healthcare at a facility. Several factors were associated with healthcare usage: perceived severity of illness (p = 0.001), occupational status of the caregiver (p = 0.002), household income (p = 0.016) and length of time since the last suspected AOM episode (p = 0.032). When confronted with a child with obvious symptoms of AOM, the majority of caregivers reported seeking healthcare. This behaviour appeared to be associated with factors related to the severity of the illness, the length of time since the last episode, as well as with the income and occupational status of the caregivers themselves. As many episodes of AOM present with non-specific respiratory symptoms, our results apply only to caregivers who were confronted with children with an obvious symptom.

Influence of pneumococcal conjugate vaccines on acute otitis media in Japan.

PubMed

Sasaki, Atsushi; Kunimoto, Masaru; Takeno, Sachio; Sumiya, Takahiro; Ishino, Takashi; Sugino, Hirotoshi; Hirakawa, Katsuhiro

2017-11-01

This study investigated: (i) changes in the incidence of acute otitis media (AOM) following introduction of public funding for free inoculation with 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13, respectively) and (ii) changes in the rate of myringotomies for AOM (MyfA) in children 1year following the publication of the first edition of the clinical practice guidelines for the diagnosis and management of AOM in children in Japan. PCV7 was launched on the Japanese market in 2010 and gained public funding in 2011. PCV7 was replaced with PCV13 in November 2013. Using the Japan Medical Data Center Claims Database, an 11-year study conducted between January 2005 and December 2015 investigated the decline in the incidence of visits to medical institutions (VtMI) due to all-cause AOM in children <15years. The rate of MyfA from January 2007 to December 2015was also investigated and changes before and after introduction of public funding for PCV7 (pfPCV7) and PCV13 (pfPCV13) for children were examined. Statistical data for the age group between 10 years and <15years served as the control. An analysis was conducted to examine changes for each age group, from infants that had received PCVs to children <5years. Statistical analysis was performed using the chi-square test and Ryan's multiple comparison tests. Ryan's multiple comparison tests were applied at a 5% level of significance. Due to significant changes in the guidelines on the indications for myringotomy introduced in 2013, statistical analysis of the rate of MyfA was limited to the pre- and post-PCV7 period. After introduction of pfPCV7 and pfPCV13, no significant suppression of the incidence of VtMI was observed in any age group. There was a gradual decline in the rate of MyfA after 2011. Compared to the control group, significant differences in all age groups from infants to children <5years were observed (p<0.009, chi-square test). Within 2 years after the introduction of PCV7, a significant decline in the rate of MyfA was observed in 1- and 5-year-olds using Ryan's multiple comparison tests at a 5% level of significance. The preventative effect of PCVs on AOM was not established in this study. There was, however, a significant decline in the rate of MyfA among 1- and 5-year-olds. Taking into consideration past studies, PCV7 may play a role in preventing the aggravation of AOM in 1-year-olds. When evaluating the effectiveness of PCVs, measures to evaluate severity may be as important as evaluating disease prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Systemic corticosteroids for acute otitis media in children.

PubMed

Ranakusuma, Respati W; Pitoyo, Yupitri; Safitri, Eka D; Thorning, Sarah; Beller, Elaine M; Sastroasmoro, Sudigdo; Del Mar, Chris B

2018-03-15

Acute otitis media (AOM) is a common acute infection in children. Pain is its most prominent and distressing symptom. Antibiotics are commonly prescribed for AOM, although they have only a modest effect in reducing pain at two to three days. There is insufficient evidence for benefits of other treatment options, including systemic corticosteroids. However, systemic corticosteroids are potent anti-inflammatory drugs, and so theoretically could be effective, either alone or as an addition to antibiotics. To assess the effects of systemic corticosteroids (oral or parenteral), with or without antibiotics, for AOM in children. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) which contains the Cochrane ARI Group's Specialised Register, MEDLINE (Ovid), Embase (Elsevier), CINAHL (EBSCO), Web of Science (Thomson Reuters), and LILACS (BIREME) for published studies, and ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) for completed and ongoing studies, to 20 February 2018. We checked the reference lists of all primary studies and review articles for additional references and contacted experts in the field to identify additional unpublished materials. We included randomised controlled trials of children with AOM that compared any systemic corticosteroid (oral or parenteral) with placebo, either with antibiotics (corticosteroid plus antibiotic versus placebo plus antibiotic) or without antibiotics (corticosteroid versus placebo). Three review authors (EDS, RR, YP) independently screened the titles and abstracts and retrieved the full texts of potentially relevant studies. We independently extracted study characteristics and outcome data from the included studies, and assessed the risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We assessed study quality using the GRADE method. We included two studies involving 252 children with AOM aged from three months to six years receiving hospital ambulatory care who were treated with intramuscular ceftriaxone, and who were then randomised to the corticosteroid group (corticosteroid and corticosteroid plus antihistamine) or the placebo group (antihistamine and double placebo). In one study, children also had a needle aspiration of middle ear fluid. Both studies were at unclear risk of bias for allocation concealment, and unclear to high risk of bias for selective reporting.One study (N = 179) included pain as an outcome, but we were unable to derive the proportion of children with persistent pain at Day 5 and Day 14. Reduction of overall or specific symptoms was presented as improvement in clinical symptoms and resolution of inflamed tympanic membranes without the need for additional antibiotic treatment: at Day 5 (94% of children in the treatment group (N = 89) versus 89% in the placebo group (N = 90); risk ratio (RR) 1.06, 95% confidence interval (CI) 0.97 to 1.16) and Day 14 (91% versus 87%; RR 1.05, 95% CI 0.95 to 1.17). Low-quality evidence meant that we are uncertain of the effectiveness of corticosteroids for this outcome.The second study (N = 73) reported a reduction of overall or specific symptoms without additional antibiotic treatment during the first two weeks as a favourable outcome. Children in the treatment group had more favourable outcomes (adjusted odds ratio 65.9, 95% CI 1.28 to 1000; P = 0.037), although the numbers were small. We were unable to pool the results with the other study because it did not report the proportion of children with this outcome by treatment group. Only one study reported adverse effects of corticosteroids (e.g. drowsiness, nappy rash), but did not quantify incidence, so we were unable to draw conclusions about adverse effects. Neither study reported a reduction in overall or specific symptom duration. The evidence for the effect of systemic corticosteroids on AOM is of low to very low quality, meaning the effect of systemic corticosteroids on important clinical outcomes in AOM remains uncertain. Large, high-quality studies are required to resolve the question.

Cost and Utilization of Retail Clinics vs. Other Providers for Treatment of Pediatric Acute Otitis Media.

PubMed

Duncan, Ian; Clark, Kara; Wang, Stacy

2016-10-01

A common acute condition seen by providers in retails clinics is the evaluation and treatment of acute otitis media (AOM) in children younger than age 20. Annual direct treatment costs for AOM were US $5.3 billion in 1998 dollars. Based on the experience of a large retail pharmacy employer, the authors compared AOM episodes in covered dependents younger than age 20 in retail clinic states to those in states without retail clinic access. Relative costs as well as frequency of visits and antibiotic prescriptions were analyzed for both retail clinic-based, and non-retail clinic-based episodes. Rates of AOM episodes were lower in retail clinic than in non-retail clinic states (62.5 vs. 76.9 per 1000 members per year; P < .0001). The average number of visits per episode was similar between retail clinic and non-retail clinic states (1.417 vs. 1.430, respectively; P = 0.657), suggesting that retail clinics do not result in an increase in overall utilization. On a risk-adjusted basis, retail clinic episodes cost approximately $30-$130 less than community episodes, depending on year. In retail clinic states, the antibiotic prescription fill rate was 95.4% for retail clinic episodes and 82.8% for community episodes, consistent with rates in the literature. This study confirms results of earlier studies that retail clinics are a less costly setting than the community for the treatment of episodes of otitis media There also is little evidence that retail clinics lead to duplication of services (patients receiving follow-up care in other settings).

Randomized controlled pilot study to compare Homeopathy and Conventional therapy in Acute Otitis Media.

PubMed

Sinha, M N; Siddiqui, V A; Nayak, C; Singh, Vikram; Dixit, Rupali; Dewan, Deepti; Mishra, Alok

2012-01-01

To compare the effectiveness of Homeopathy and Conventional therapy in Acute Otitis Media (AOM). A randomized placebo-controlled parallel group pilot study of homeopathic vs conventional treatment for AOM was conducted in Jaipur, India. Patients were randomized by a computer generated random number list to receive either individualized homeopathic medicines in fifty millesimal (LM) potencies, or conventional treatment including analgesics, antipyretics and anti-inflammatory drugs. Patients who did not improve were prescribed antibiotics at the 3rd day. Outcomes were assessed by the Acute Otitis Media-Severity of Symptoms (AOM-SOS) Scale and Tympanic Membrane Examination over 21 days. 81 patients were included, 80 completed follow-up: 41 for conventional and 40 for homeopathic treatment. In the Conventional group, all 40 (100%) patients were cured, in the Homeopathy group, 38 (95%) patients were cured while 02 (5%) patients were lost to the last two follow-up. By the 3rd day of treatment, 4 patients were cured in Homeopathy group but in Conventional group only one patient was cured. In the Conventional group antibiotics were prescribed in 39 (97.5%), no antibiotics were required in the Homeopathy group. 85% of patients were prescribed six homeopathic medicines. Individualized homeopathy is an effective conventional treatment in AOM, there were no significant differences between groups in the main outcome. Symptomatic improvement was quicker in the Homeopathy group, and there was a large difference in antibiotic requirements, favouring homeopathy. Further work on a larger scale should be conducted. Copyright © 2011 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

Factors controlling the abundance of organic sulfur in flash pyrolyzates of Upper Cretaceous kerogens from Sergipe Basin, Brazil

USGS Publications Warehouse

Carmo, A.M.; Stankiewicz, B.A.; Mastalerz, Maria; Pratt, L.M.

1997-01-01

The molecular and elemental composition of immature kerogens isolated from Upper Cretaceous marine carbonates from Sergipe Basin, Brazil were investigated using combined pyrolysis-gas chromatography/mass spectrometry and organic petrographic techniques. The kerogens are predominantly composed of reddish-fluorescing amorphous organic matter (AOM) and variable amounts of yellow-fluorescing alginite and liptodetrinite. The abundance of organic sulfur in the kerogens inferred from the ratio 2-ethyl-5-methylthiophene/(1,2-dimethylbenzene + dec-1-ene) in the pyrolyzates is variable and may be related to changes in the type of primary organic input and/or to variations in rates of bacterial sulfate reduction. A concomitant increase in S/C and O/C ratios determined in situ using the electron microprobe is observed in AOM and alginites and may be related to a progressive oxidation of the organic matter during sulfurization. The S/C ratio of the AOM is systematically higher than the S C ratio of the alginites. Combined with a thiophene distribution characteristic of pyrolyzates of Type II organic matter, the higher S/C of AOM in Sergipe kerogens suggests that sulfurization and incorporation of low-molecular weight lipids derived from normal marine organic matter into the kerogen structure predominated over direct sulfurization of highly aliphatic algal biomacromolecules.The molecular and elemental composition of immature kerogens isolated from Upper Cretaceous marine carbonates from Sergipe Basin, Brazil were investigated using combined pyrolysis-gas chromatography/mass spectrometry and organic petrographic techniques. The kerogens are predominantly composed of reddish-fluorescing amorphous organic matter (AOM) and variable amounts of yellow-fluorescing alginite and liptodetrinite. The abundance of organic sulfur in the kerogens inferred from the ratio 2-ethyl-5-methylthiophene/(1,2-dimethylbenzene+dec-1-ene) in the pyrolyzates is variable and may be related to changes in the type of primary organic input and/or to variations in rates of bacterial sulfate reduction. A concomitant increase in S/C and O/C ratios determined in situ using the electron microprobe is observed in AOM and alginites and may be related to a progressive oxidation of the organic matter during sulfurization. The S/C ratio of the AOM is systematically higher than the S/C ratio of the alginites. Combined with a thiophene distribution characteristic of pyrolyzates of Type II organic matter, the higher S/C of AOM in Sergipe kerogens suggests that sulfurization and incorporation of low-molecular weight lipids derived from normal marine organic matter into the kerogen structure predominated over direct sulfurization of highly aliphatic algal biomacromolecules.

Decline in Early Childhood Respiratory Tract Infections in the Norwegian Mother and Child Cohort Study after Introduction of Pneumococcal Conjugate Vaccination

PubMed Central

Magnus, Maria C.; Vestrheim, Didrik F.; Nystad, Wenche; Håberg, Siri Eldevik; Stigum, Hein; London, Stephanie J.; Bergsaker, Marianne A. R.; Caugant, Dominique A.; Aaberge, Ingeborg S.; Nafstad, Per

2012-01-01

BACKGROUND The seven-valent pneumococcal conjugate vaccine (PCV7) was introduced into the Norwegian Childhood Immunization Program in 2006. A substantial effectiveness of PCV7 immunization against invasive pneumococcal disease has been demonstrated, while evidence of the impact on respiratory tract infections are less consistent. METHODS This study included children participating in the Norwegian Mother and Child Cohort Study, which recruited pregnant women between 1999 and 2008. Maternal report of acute otitis media (AOM), lower respiratory tract infections (LRTIs) and asthma in the child was compared with PCV7 immunization status, as obtained from the Norwegian Immunization Registry. Generalized linear models with the log link function were used to report adjusted relative risks (RR) and 95% confidence intervals (CI). RESULTS For children who had received three or more PCV7 immunizations by 12 months of age, the adjusted relative risks of AOM and LRTIs between 12 and 18 months were 0.86 [95% CI: 0.81, 0.91] and 0.78 [95% CI: 0.70, 0.87] respectively, when compared with non-immunized children. A reduced risk of AOM, RR 0.92 [95% CI: 0.90, 0.94], and LRTIs, RR 0.75 [95%CI: 0.71, 0.80], between 18 and 36 months of age was also identified among children who had received 3 or more immunizations by 18 months. No association was seen between PCV7 immunization and asthma at 36 months of age. CONCLUSION Reduced incidence proportions of AOM and LRTIs before 36 months of age were observed among children immunized with PCV7 through the childhood immunization program. PMID:22627867

The nitrogen cycle in anaerobic methanotrophic mats of the Black Sea is linked to sulfate reduction and biomass decomposition.

PubMed

Siegert, Michael; Taubert, Martin; Seifert, Jana; von Bergen-Tomm, Martin; Basen, Mirko; Bastida, Felipe; Gehre, Matthias; Richnow, Hans-Hermann; Krüger, Martin

2013-11-01

Anaerobic methanotrophic (ANME) mats host methane-oxidizing archaea and sulfate-reducing prokaryotes. Little is known about the nitrogen cycle in these communities. Here, we link the anaerobic oxidation of methane (AOM) to the nitrogen cycle in microbial mats of the Black Sea by using stable isotope probing. We used four different (15)N-labeled sources of nitrogen: dinitrogen, nitrate, nitrite and ammonium. We estimated the nitrogen incorporation rates into the total biomass and the methyl coenzyme M reductase (MCR). Dinitrogen played an insignificant role as nitrogen source. Assimilatory and dissimilatory nitrate reduction occurred. High rates of nitrate reduction to dinitrogen were stimulated by methane and sulfate, suggesting that oxidation of reduced sulfur compounds such as sulfides was necessary for AOM with nitrate as electron acceptor. Nitrate reduction to dinitrogen occurred also in the absence of methane as electron donor but at six times slower rates. Dissimilatory nitrate reduction to ammonium was independent of AOM. Ammonium was used for biomass synthesis under all conditions. The pivotal enzyme in AOM coupled to sulfate reduction, MCR, was synthesized from nitrate and ammonium. Results show that AOM coupled to sulfate reduction along with biomass decomposition drive the nitrogen cycle in the ANME mats of the Black Sea and that MCR enzymes are involved in this process. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

The effectiveness of advance organiser model on students' academic achievement in learning work and energy

NASA Astrophysics Data System (ADS)

Gidena, Asay; Gebeyehu, Desta

2017-11-01

The purpose of this study was to investigate the effectiveness of the advance organiser model (AOM) on students' academic achievement in learning work and energy. The design of the study was quasi-experimental pretest-posttest nonequivalent control groups. The total population of the study was 139 students of three sections in Endabaguna preparatory school in Tigray Region, Ethiopia. Two sections with equivalent means on the pretest were taken to participate in the study purposely and one section assigned as the experimental group and the other section assigned as the control group randomly. The experimental group was taught using the lesson plan based on the AOM, and the control group was taught using the lesson plan based on the conventional teaching method. Pretest and posttest were administered before and after the treatment, respectively. Independent sample t-test was used to analyse the data at the probability level of 0.05. The findings of the study showed that the AOM was more effective than the conventional teaching method with effect size of 0.49. This model was also effective to teach male and female students and objectives namely understanding and application. However, both methods were equally important to teach work and energy under the objective knowledge level.

Multiple sulfur isotope constraints on sulfate-driven anaerobic oxidation of methane: Evidence from authigenic pyrite in seepage areas of the South China Sea

NASA Astrophysics Data System (ADS)

Lin, Zhiyong; Sun, Xiaoming; Strauss, Harald; Lu, Yang; Gong, Junli; Xu, Li; Lu, Hongfeng; Teichert, Barbara M. A.; Peckmann, Jörn

2017-08-01

Multiple sulfur isotope signatures and secondary ion mass spectroscopy (SIMS) sulfur isotope compositions of pyrite from two seafloor sites (DH-CL11 and HD109) in seepage areas of the South China Sea were measured in order to study isotope effects of sulfate-driven anaerobic oxidation of methane (SO4-AOM). The multiple sulfur isotopes of pyrite reveal variable ranges for both sites (δ34S: between -44.1‰ and -2.9‰ for DH-CL11 and between -43.8‰ and -1.6‰ for HD109; Δ33S: between 0.02‰ and 0.17‰ for DH-CL11 and between -0.03‰ and 0.14‰ for HD109). SIMS analysis reveals an extreme variability of δ34S values (between -50.3‰ and -2.7‰ in DH-CL11; between -50.1 and 52.4‰ in HD109) for three types of pyrite: (1) framboids, (2) zoned aggregates with radial overgrowth surrounding a framboidal core, and (3) euhedral pyrite crystals. The synchronous changes of geochemical proxies (sulfate and methane concentrations, δ34Ssulfate and δ18Osulfate, δ34Spyrite, and pyrite content) at the sulfate-methane transition zone (SMTZ) at site DH-CL11 are interpreted to be induced by SO4-AOM under steady state conditions. In contrast, pyrite content and δ34S value fluctuations throughout core HD109 suggest that the sediment at this site was affected by multiple pyritization events during diagenesis. Multiple sulfur isotope signatures of early diagenetic pyrite (i.e., with low and high δ34S values, the latter above 315 cmbsf in DH-CL11; above 70 cmbsf in HD109) in the upper sediment column suggest that organoclastic sulfate reduction (OSR) and sulfur disproportionation generated the observed isotopic signatures. In contrast to the early diagenetic 34S depleted framboids, the higher SIMS δ34S values of overgrowth and euhedral crystals suggest a late diagenetic 34S enriched pool of dissolved sulfide derived from SO4-AOM at the current and paleo-SMTZs. Interestingly, pyrite resulting from SO4-AOM in the SMTZ at site DH-CL11 reveals a distinct pattern with higher Δ33S values, different from pyrite resulting from OSR and sulfur disproportionation. Therefore, paired δ34S and Δ33S values may allow to differentiate OSR and SO4-AOM, although a full understanding of the isotope effects associated with SO4-AOM is hampered by uncertainties on the actual electron transfer mechanism in the syntrophic SO4-AOM consortium.

Community Composition and Ultrastructure of a Nitrate-Dependent Anaerobic Methane-Oxidizing Enrichment Culture.

PubMed

Gambelli, Lavinia; Guerrero-Cruz, Simon; Mesman, Rob J; Cremers, Geert; Jetten, Mike S M; Op den Camp, Huub J M; Kartal, Boran; Lueke, Claudia; van Niftrik, Laura

2018-02-01

Methane is a very potent greenhouse gas and can be oxidized aerobically or anaerobically through microbe-mediated processes, thus decreasing methane emissions in the atmosphere. Using a complementary array of methods, including phylogenetic analysis, physiological experiments, and light and electron microscopy techniques (including electron tomography), we investigated the community composition and ultrastructure of a continuous bioreactor enrichment culture, in which anaerobic oxidation of methane (AOM) was coupled to nitrate reduction. A membrane bioreactor was seeded with AOM biomass and continuously fed with excess methane. After 150 days, the bioreactor reached a daily consumption of 10 mmol nitrate · liter -1 · day -1 The biomass consisted of aggregates that were dominated by nitrate-dependent anaerobic methane-oxidizing " Candidatus Methanoperedens"-like archaea (40%) and nitrite-dependent anaerobic methane-oxidizing " Candidatus Methylomirabilis"-like bacteria (50%). The " Ca Methanoperedens" spp. were identified by fluorescence in situ hybridization and immunogold localization of the methyl-coenzyme M reductase (Mcr) enzyme, which was located in the cytoplasm. The " Ca Methanoperedens" sp. aggregates consisted of slightly irregular coccoid cells (∼1.5-μm diameter) which produced extruding tubular structures and putative cell-to-cell contacts among each other. " Ca Methylomirabilis" sp. bacteria exhibited the polygonal cell shape typical of this genus. In AOM archaea and bacteria, cytochrome c proteins were localized in the cytoplasm and periplasm, respectively, by cytochrome staining. Our results indicate that AOM bacteria and archaea might work closely together in the process of anaerobic methane oxidation, as the bacteria depend on the archaea for nitrite. Future studies will be aimed at elucidating the function of the cell-to-cell interactions in nitrate-dependent AOM. IMPORTANCE Microorganisms performing nitrate- and nitrite-dependent anaerobic methane oxidation are important in both natural and man-made ecosystems, such as wastewater treatment plants. In both systems, complex microbial interactions take place that are largely unknown. Revealing these microbial interactions would enable us to understand how the oxidation of the important greenhouse gas methane occurs in nature and pave the way for the application of these microbes in wastewater treatment plants. Here, we elucidated the microbial composition, ultrastructure, and physiology of a nitrate-dependent AOM community of archaea and bacteria and describe the cell plan of " Ca Methanoperedens"-like methanotrophic archaea. Copyright © 2018 American Society for Microbiology.

Antidiarrheal effect of Alpinia oxyphylla Miq. (Zingiberaceae) in experimental mice and its possible mechanism of action.

PubMed

Wang, Sheng; Zhao, Yang; Zhang, Junqing; Huang, Xiaoxing; Wang, Yifei; Xu, Xiaotao; Zheng, Bin; Zhou, Xue; Tian, Huajie; Liu, Li; Mei, Qibing

2015-06-20

The fructus Alpinia oxyphylla Miq. (AOM) has been used for treating diarrhea with spleen deficiency and gastralgia for thousands of years. A number of traditional Chinese medicine formulae provide AOM as an alternative herbal treatment for diarrhea, but the scientific basis for this usage has not been well defined. In this study, we tried to investigate the antidiarrheal activity and possible mechanisms of Fructus AOM, aiming to enrich our understanding to the scientific meanings and theoretical significance of Fructus AOM in clinical practice. The fructus of AOM collected from Hainan province in China were macerated in the 95% ethanol to obtain the crude 95% ethanol extract, followed by subjected to chromatographic separation over a Diaion HP20 column to obtain 90% and 50% ethanol eluted fractions. The activities of the crude extract and fractions on castor oil induced acute diarrhea, rhubarb induced chronic diarrhea, gastrointestinal transit (GIT) in mice, and contractions of isolated guinea-pig ileum were evaluated. Additionally, nitric oxide (NO), gastrointestinal peptides gastrin (GAS), motilin (MTL) and somatostatin (SS) levels that related to gastrointestinal motilities were detected to demonstrate the potential mechanisms. Ultimately, LC-MS/MS method was utilized to ensure the chemical consistency. The 95% ethanol extract and 90% ethanol eluted fraction significantly delayed the onset time and decreased the wet faeces proportion compared with control group in the castor oil induced acute diarrhea mice. In terms of further evaluation of antidiarrheal activity, the 95% ethanol extract and 90% ethanol elution displayed significant inhibition of the intestinal propulsion at the two highest oral doses of 20 g crude drug/kg and 1g/kg. Moreover the 95% ethanol extract (10 and 20 g crude drug/kg) and 90% ethanol elution (0.5 and 1g/kg) could significantly inhibit the GIT, which was partially attributed to the increase in NO and SS levels, and the decreased MTL. In vitro spontaneous contractions of the isolated guinea pig ileum induced by carbachol, neostigmine and histamine were attenuated by both the extract and elution. Phytochemical analysis of 95% ethanol extract and its fractions identified the presence of diphenylheptanes, sesquiterpenes, and flavones as the major components. Our in vivo and in vitro data could partly support and justify the traditional usage of Fructus AOM on the treatment of diarrhea in traditional medicine. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Metabolic Capabilities of Microorganisms Involved in and Associated with the Anaerobic Oxidation of Methane

PubMed Central

Wegener, Gunter; Krukenberg, Viola; Ruff, S. Emil; Kellermann, Matthias Y.; Knittel, Katrin

2016-01-01

In marine sediments the anaerobic oxidation of methane with sulfate as electron acceptor (AOM) is responsible for the removal of a major part of the greenhouse gas methane. AOM is performed by consortia of anaerobic methane-oxidizing archaea (ANME) and their specific partner bacteria. The physiology of these organisms is poorly understood, which is due to their slow growth with doubling times in the order of months and the phylogenetic diversity in natural and in vitro AOM enrichments. Here we study sediment-free long-term AOM enrichments that were cultivated from seep sediments sampled off the Italian Island Elba (20°C; hereon called E20) and from hot vents of the Guaymas Basin, Gulf of California, cultivated at 37°C (G37) or at 50°C (G50). These enrichments were dominated by consortia of ANME-2 archaea and Seep-SRB2 partner bacteria (E20) or by ANME-1, forming consortia with Seep-SRB2 bacteria (G37) or with bacteria of the HotSeep-1 cluster (G50). We investigate lipid membrane compositions as possible factors for the different temperature affinities of the different ANME clades and show autotrophy as characteristic feature for both ANME clades and their partner bacteria. Although in the absence of additional substrates methane formation was not observed, methanogenesis from methylated substrates (methanol and methylamine) could be quickly stimulated in the E20 and the G37 enrichment. Responsible for methanogenesis are archaea from the genus Methanohalophilus and Methanococcoides, which are minor community members during AOM (1–7‰ of archaeal 16S rRNA gene amplicons). In the same two cultures also sulfur disproportionation could be quickly stimulated by addition of zero-valent colloidal sulfur. The isolated partner bacteria are likewise minor community members (1–9‰ of bacterial 16S rRNA gene amplicons), whereas the dominant partner bacteria (Seep-SRB1a, Seep-SRB2, or HotSeep-1) did not grow on elemental sulfur. Our results support a functioning of AOM as syntrophic interaction of obligate methanotrophic archaea that transfer non-molecular reducing equivalents (i.e., via direct interspecies electron transfer) to obligate sulfate-reducing partner bacteria. Additional katabolic processes in these enrichments but also in sulfate methane interfaces are likely performed by minor community members. PMID:26870011

Serum antibody response to Moraxella catarrhalis proteins OMP CD, OppA, Msp22, Hag, and PilA2 after nasopharyngeal colonization and acute otitis media in children.

PubMed

Ren, Dabin; Almudevar, Anthony L; Murphy, Timothy F; Lafontaine, Eric R; Campagnari, Anthony A; Luke-Marshall, Nicole; Casey, Janet R; Pichichero, Michael E

2015-10-26

There is no licensed vaccine for Moraxella catarrhalis (Mcat), which is a prominent bacterium causing acute otitis media (AOM) in children and lower respiratory tract infections in adults. Nasopharyngeal (NP) colonization caused by respiratory bacteria results in natural immunization of the host. To identify Mcat antigens as vaccine candidates, we evaluated the development of naturally induced antibodies to 5 Mcat surface proteins in children 6-30 months of age during Mcat NP colonization and AOM. Human serum IgG against the recombinant Mcat proteins, outer membrane protein (OMP) CD, oligopeptide permease (Opp)A, hemagglutinin (Hag), Moraxella surface protein (Msp)22, and PilA clade 2 (PilA2) was quantitated by using an ELISA assay. There were 223 Mcat NP colonization episodes documented in 111 (60%) of 184 children in the study. Thirty five Mcat AOM episodes occurred in 30 (16%) of 184 children. All 5 Mcat candidate vaccine antigens evaluated stimulated a significant rise in serum IgG levles over time from 6 to 36 months of age (P<0.001), with a rank order as follows: Msp22=OppA>OMP CD=Hag=PilA2. Children with no detectable Mcat NP colonization showed a higher serum IgG level against OppA, Hag, and Msp22 compared to those with Mcat NP colonization (P<0.05). Individual data showed that some children responded to AOM with an antibody increase to one or more of the studied Mcat proteins but some children failed to respond. Serum antibody to Mcat candidate vaccine proteins OMP CD, OppA, Msp22, Hag, and PilA2 increased with age in naturally immunized children age 6-30 months following Mcat NP colonization and AOM. High antibody levels against OppA, Msp22, and Hag correlated with reduced carriage. The results support further investigation of these vaccine candidates in protecting against Mcat colonization and infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Serum antibody response to Moraxella catarrhalis proteins OMP CD, OppA, Msp22, Hag, and PilA2 after nasopharyngeal colonization and acute otitis media in children

PubMed Central

Ren, Dabin; Almudevar, Anthony L.; Murphy, Timothy F.; Lafontaine, Eric R.; Campagnari, Anthony A.; Luke-Marshall, Nicole; Casey, Janet R.; Pichichero, Michael E.

2015-01-01

Background There is no licensed vaccine for Moraxella catarrhalis (Mcat), which is a prominent bacterium causing acute otitis media (AOM) in children and lower respiratory tract infections in adults. Nasopharyngeal (NP) colonization caused by respiratory bacteria results in natural immunization of the host. To identify Mcat antigens as vaccine candidates, we evaluated the development of naturally induced antibodies to 5 Mcat surface proteins in children 6–30 months of age during Mcat NP colonization and AOM. Methods Human serum IgG against the recombinant Mcat proteins, outer membrane protein (OMP) CD, oligopeptide permease (Opp)A, hemagglutinin (Hag), Moraxella surface protein (Msp)22, and PilA clade 2 (PilA2) was quantitated by using an ELISA assay. Results There were 223 Mcat NP colonization episodes documented in 111 (60%) of 184 children in the study. Thirty five Mcat AOM episodes occurred in 30 (16%) of 184 children. All 5 Mcat candidate vaccine antigens evaluated stimulated a significant rise in serum IgG levles over time from 6 to 36 months of age (P < 0.001), with a rank order as follows: Msp22 = OppA > OMP CD = Hag = PilA2. Children with no detectable Mcat NP colonization showed a higher serum IgG level against OppA, Hag, and Msp22 compared to those with Mcat NP colonization (P < 0.05). Individual data showed that some children responded to AOM with an antibody increase to one or more of the studied Mcat proteins but some children failed to respond. Conclusions Serum antibody to Mcat candidate vaccine proteins OMP CD, OppA, Msp22, Hag, and PilA2 increased with age in naturally immunized children age 6–30 months following Mcat NP colonization and AOM. High antibody levels against OppA, Msp22, and Hag correlated with reduced carriage. The results support further investigation of these vaccine candidates in protecting against Mcat colonization and infection. PMID:26392013

Ergosterol peroxide from Chaga mushroom (Inonotus obliquus) exhibits anti-cancer activity by down-regulation of the β-catenin pathway in colorectal cancer.

PubMed

Kang, Ju-Hee; Jang, Jeong-Eun; Mishra, Siddhartha Kumar; Lee, Hee-Ju; Nho, Chu Won; Shin, Dongyun; Jin, Mirim; Kim, Mi Kyung; Choi, Changsun; Oh, Seung Hyun

2015-09-15

In this study, we examined the effect of different fractions and components of Chaga mushroom (Inonotus Obliquus) on viability and apoptosis of colon cancer cells. Among them, one component showed the most effective growth inhibition and was identified as ergosterol peroxide by NMR analysis. We investigated the anti-proliferative and apoptosis mechanisms of ergosterol peroxide associated with its anti-cancer activities in human colorectal cancer (CRC) cell lines and tested its anti-tumor effect on colitis-induced CRC developed by Azoxymethane (AOM)/Dextran sulfate sodium (DSS) in a mouse model. We used MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays, flow cytometry assays, Western blot analysis, colony formation assays, reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and AOM/DSS mouse models to study the molecular mechanism of metastatic activities in CRC cells. Ergosterol peroxide inhibited cell proliferation and also suppressed clonogenic colony formation in HCT116, HT-29, SW620 and DLD-1 CRC cell lines. The growth inhibition observed in these CRC cell lines was the result of apoptosis, which was confirmed by FACS analysis and Western blotting. Ergosterol peroxide inhibited the nuclear levels of β-catenin, which ultimately resulted in reduced transcription of c-Myc, cyclin D1, and CDK-8. Ergosterol peroxide administration showed a tendency to suppress tumor growth in the colon of AOM/DSS-treated mice, and quantification of the IHC staining showed a dramatic decrease in the Ki67-positive staining and an increase in the TUNEL staining of colonic epithelial cells in AOM/DSS-treated mice by ergosterol peroxide for both prevention and therapy. Our data suggest that ergosterol peroxide suppresses the proliferation of CRC cell lines and effectively inhibits colitis-associated colon cancer in AOM/DSS-treated mice. Ergosterol peroxide down-regulated β-catenin signaling, which exerted anti-proliferative and pro-apoptotic activities in CRC cells. These properties of ergosterol peroxide advocate its use as a supplement in colon cancer chemoprevention. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Quercetin and rutin as inhibitors of azoxymethanol-induced colonic neoplasia.

PubMed

Deschner, E E; Ruperto, J; Wong, G; Newmark, H L

1991-07-01

Dietary quercetin (QU) and rutin (RU), phenolic flavonoids commonly found in many fruits and vegetables, were provided to CF1 female mice for 50 weeks to assess the ability of these compounds to inhibit azoxymethanol (AOM)-induced colonic neoplasia. In addition to a control group fed an AIN 76A diet, five other groups received that diet to which was added either 0.1, 0.5 or 2.0% QU and 1.0 or 4.0% RU. Acute studies revealed that, among saline controls, no alteration of any proliferative parameters of colonic epithelial cells was observed among those groups receiving any dose of QU or RU. However, among the AOM-treated mice, both 2% QU and 4% RU significantly reduced hyperproliferation and inhibited the shift of S-phase cells to the middle and upper portion of crypts. Moreover, mice fed these concentrations of QU and RU had significantly fewer AOM-induced focal areas of dysplasia (FADs) than those fed the control diet (0.2 +/- 0.4 and 0.4 +/- 0.5 versus 3.6 +/- 2.3 respectively). Tumors occurred more frequently in the distal half of the colon, regardless of treatment. Compared with controls, mice fed 2% QU had a significantly reduced tumor incidence (25.0% versus 5.9%, P = 0.03). Those fed 4% RU showed only a trend toward inhibition (25% versus 9.7%, P = 0.11). Nevertheless, both 2% QU and 4% RU suppressed tumor multiplicity, i.e. fewer tumors/animal arose in these groups than in the AOM-treated control mice (1.2 versus 2.3, P = 0.005; 1.1 versus 2.3, P = 0.003 respectively). Clearly, QU and RU exhibit significant activity in reducing AOM-induced hyperproliferation of colonic epithelial cells and FAD incidence. This behavior successfully forecast the ability of both flavonoids to suppress tumor multiplicity and ultimately tumor development.

Comparative DNA adduct formation and induction of colonic aberrant crypt foci in mice exposed to 2-amino-9H-pyrido[2,3-b]indole, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline and azoxymethane

PubMed Central

Kim, Sangyub; Guo, Jingshu; O’Sullivan, M. Gerald; Gallaher, Daniel D.; Turesky, Robert J.

2015-01-01

Considerable evidence suggests that environmental factors, including diet and cigarette smoke, are involved in the pathogenesis of colon cancer. Carcinogenic nitroso compounds (NOC), such as N-nitrosodimethylamine (NDMA), are present in tobacco and processed red meat, and NOC have been implicated in colon cancer. Azoxymethane (AOM), commonly used for experimental colon carcinogenesis, is an isomer of NDMA, and it produces the same DNA adducts as does NDMA. Heterocyclic aromatic amines (HAAs) formed during the combustion of tobacco and high-temperature cooking of meats are also associated with an elevated risk of colon cancer. The most abundant carcinogenic HAA formed in tobacco smoke is 2-amino-9H-pyrido[2,3-b]indole (AαC), whereas 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) is the most potent carcinogenic HAA formed during the cooking of meat and fish. However, the comparative tumor-initiating potential of AαC, MeIQ, and AOM is unknown. In this report, we evaluate the formation of DNA adducts as a measure of genotoxicity, and the induction of colonic aberrant crypt foci (ACF) and dysplastic ACF, as an early measure of carcinogenic potency of these compounds in the colon of male A/J mice. Both AαC and AOM induced a greater number of DNA adducts than MeIQ in the liver and colon. AOM induced a greater number of ACF and dysplastic ACF than either AαC or MeIQ. Conversely, based on adduct levels, MeIQ-DNA adducts were more potent than AαC- and AOM-DNA adducts at inducing ACF. Long-term feeding studies are required to relate levels of DNA adducts, induction of ACF, and colon cancer by these colon genotoxicants. PMID:26734915

The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

PubMed Central

Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Al-Henhena, Nawal; Kunasegaran, Thubasni; Hasanpourghadi, Mohadeseh; Looi, Chung Yeng; Abd Malek, Sri Nurestri; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

2015-01-01

Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation in AOM-treated rats and may offer protection against colon cancer development. PMID:26251570

Algal removal from cyanobacteria-rich waters by preoxidation-assisted coagulation-flotation: Effect of algogenic organic matter release on algal removal and trihalomethane formation.

PubMed

Lin, Jr-Lin; Hua, Lap-Cuong; Hung, Shih Kai; Huang, Chihpin

2018-01-01

The cyanobacteria-bloom in raw waters frequently causes an unpredictable chemical dosing of preoxidation and coagulation for an effective removal of algal cells in water treatment plants. This study investigated the effects of preoxidation with NaOCl and ClO 2 on the coagulation-flotation effectiveness in the removal of two commonly blooming cyanobacteria species, Microcystis aeruginosa (MA) and Cylindrospermopsis raciborskii (CR), and their corresponding trihalomethane (THM) formation potential. The results showed that dual dosing with NaOCl plus ClO 2 was more effective in enhancing the deformation of cyanobacterial cells compared to single dosing with NaOCl, especially for CR-rich water. Both preoxidation approaches for CR-rich water effectively reduced the CR cell count with less remained dissolved organic carbon (DOC), which benefited subsequent coagulation-flotation. However, preoxidation led to an adverse release of algogenic organic matter (AOM) in the case of MA-rich water. The release of AOM resulted in a poor removal in MA cells and a large amount of THM formation after oxidation-assisted coagulation-flotation process. The reduction in THM formation potential of CR-rich waters is responsible for effective algae and DOC removal by alum coagulation. It is concluded that the species-specific characteristic of cyanobacteria and their AOM released during chlorination significantly influences the performance of coagulation-flotation for AOM removal and corresponding THM formation. Copyright © 2017. Published by Elsevier B.V.

Ultra-high contrast retinal display system for single photoreceptor psychophysics

PubMed Central

Domdei, Niklas; Domdei, Lennart; Reiniger, Jenny L.; Linden, Michael; Holz, Frank G.; Roorda, Austin; Harmening, Wolf M.

2017-01-01

Due to the enormous dynamic range of human photoreceptors in response to light, studying their visual function in the intact retina challenges the stimulation hardware, specifically with regard to the displayable luminance contrast. The adaptive optics scanning laser ophthalmoscope (AOSLO) is an optical platform that focuses light to extremely small retinal extents, approaching the size of single photoreceptor cells. However, the current light modulation techniques produce spurious visible backgrounds which fundamentally limit experimental options. To remove unwanted background light and to improve contrast for high dynamic range visual stimulation in an AOSLO, we cascaded two commercial fiber-coupled acousto-optic modulators (AOMs) and measured their combined optical contrast. By compensating for zero-point differences in the individual AOMs, we demonstrate a multiplicative extinction ratio in the cascade that was in accordance with the extinction ratios of both single AOMs. When latency differences in the AOM response functions were individually corrected, single switch events as short as 50 ns with radiant power contrasts up to 1:1010 were achieved. This is the highest visual contrast reported for any display system so far. We show psychophysically that this contrast ratio is sufficient to stimulate single foveal photoreceptor cells with small and bright enough visible targets that do not contain a detectable background. Background-free stimulation will enable photoreceptor testing with custom adaptation lights. Furthermore, a larger dynamic range in displayable light levels can drive photoreceptor responses in cones as well as in rods. PMID:29359094

A Systematic Review of Different Implants and Approaches for Proximal Interphalangeal Joint Arthroplasty

PubMed Central

Yamamoto, Michiro; Malay, Sunitha; Fujihara, Yuki; Zhong, Lin; Chung, Kevin C.

2016-01-01

Background Outcomes after implant arthroplasty for primary degenerative and posttraumatic osteoarthritis (OA) of proximal interphalangeal (PIP) joint were different according to the implant design and surgical approach. The purpose of this systematic review was to evaluate outcomes of various types of implant arthroplasty for PIP joint OA with emphasis on different surgical approaches. Methods The authors searched all available literature in the PubMed and EMBASE databases for articles reporting on outcomes of implant arthroplasty for PIP joint OA. Data collection included active arc of motion (AOM), extension lag, and complications. We combined the data of various types of surface replacement arthroplasty into one group to compare with silicone arthroplasty. Results A total of 849 articles were screened, yielding 40 studies for final review. The mean postoperative AOM and the mean gain in AOM of silicone implant with volar approach were 58° and 17° respectively which was greater than surface replacement implant with dorsal approach as 51° and 8°, respectively. The mean postoperative extension lag of silicone implant with volar approach and surface replacement with dorsal approach was 5° and 14° respectively. The revision rate of silicone implant with volar approach and surface replacement with dorsal approach was 6% and 18% at the mean follow-up period of 41.2 and 51 months, respectively. Conclusions Silicone implant with volar approach showed the best AOM with less extension lag and fewer complications after surgery among all the implant designs and surgical approaches. PMID:28445369

Microarray Analyses of Genes Differentially Expressed by Diet (Black Beans and Soy Flour) during Azoxymethane-Induced Colon Carcinogenesis in Rats.

PubMed

Rondini, Elizabeth A; Bennink, Maurice R

2012-01-01

We previously demonstrated that black bean (BB) and soy flour (SF)-based diets inhibit azoxymethane (AOM)-induced colon cancer. The objective of this study was to identify genes altered by carcinogen treatment in normal-appearing colonic mucosa and those attenuated by bean feeding. Ninety-five male F344 rats were fed control (AIN) diets upon arrival. At 4 and 5 weeks, rats were injected with AOM (15 mg/kg) or saline and one week later administered an AIN, BB-, or SF-based diet. Rats were sacrificed after 31 weeks, and microarrays were conducted on RNA isolated from the distal colonic mucosa. AOM treatment induced a number of genes involved in immunity, including several MHC II-associated antigens and innate defense genes (RatNP-3, Lyz2, Pla2g2a). BB- and SF-fed rats exhibited a higher expression of genes involved in energy metabolism and water and sodium absorption and lower expression of innate (RatNP-3, Pla2g2a, Tlr4, Dmbt1) and cell cycle-associated (Cdc2, Ccnb1, Top2a) genes. Genes involved in the extracellular matrix (Col1a1, Fn1) and innate immunity (RatNP-3, Pla2g2a) were induced by AOM in all diets, but to a lower extent in bean-fed animals. This profile suggests beans inhibit colon carcinogenesis by modulating cellular kinetics and reducing inflammation, potentially by preserving mucosal barrier function.

Bovine milk-derived α-lactalbumin inhibits colon inflammation and carcinogenesis in azoxymethane and dextran sodium sulfate-treated mice.

PubMed

Yamaguchi, Makoto; Takai, Shoko; Hosono, Akira; Seki, Taiichiro

2014-01-01

Cyclooxygenase-2 is expressed early in colon carcinogenesis and plays crucial role in the progress of the disease. Recently, we found that α-lactalbumin had anti-inflammatory activity by inhibiting cyclooxygenase-2. In experiment 1, we investigated the effects of α-lactalbumin on the colon carcinogenesis initiated with azoxymethane (AOM) followed by promotion with dextran sodium sulfate (DSS) in mice. Dietary treatment with α-lactalbumin decreased fecal occult blood score at 3 days after DSS intake. α-Lactalbumin also decreased the colon tumor at week 9. In experiment 2, AOM-treated mice were sacrificed at 7 days after DSS intake. The plasma and colon prostaglandin E2 (PGE2) levels in AOM/DSS-treated mice were higher than those in the DSS-treated mice without initiation by AOM. α-Lactalbumin decreased PGE2 in both plasma and colon. These results suggest that α-lactalbumin effectively inhibited colon carcinogenesis, and the inhibition may be due to the decreased PGE2 by inhibiting cyclooxygenase-2 at cancer promotion stages.

Using VCL as an Aspect-Oriented Approach to Requirements Modelling

NASA Astrophysics Data System (ADS)

Amálio, Nuno; Kelsen, Pierre; Ma, Qin; Glodt, Christian

Software systems are becoming larger and more complex. By tackling the modularisation of crosscutting concerns, aspect orientation draws attention to modularity as a means to address the problems of scalability, complexity and evolution in software systems development. Aspect-oriented modelling (AOM) applies aspect-orientation to the construction of models. Most existing AOM approaches are designed without a formal semantics, and use multi-view partial descriptions of behaviour. This paper presents an AOM approach based on the Visual Contract Language (VCL): a visual language for abstract and precise modelling, designed with a formal semantics, and comprising a novel approach to visual behavioural modelling based on design by contract where behavioural descriptions are total. By applying VCL to a large case study of a car-crash crisis management system, the paper demonstrates how modularity of VCL's constructs, at different levels of granularity, help to tackle complexity. In particular, it shows how VCL's package construct and its associated composition mechanisms are key in supporting separation of concerns, coarse-grained problem decomposition and aspect-orientation. The case study's modelling solution has a clear and well-defined modular structure; the backbone of this structure is a collection of packages encapsulating local solutions to concerns.

In-vitro bacterial identification using fluorescence spectroscopy with an optical fiber system

NASA Astrophysics Data System (ADS)

Spector, Brian C.; Werkhaven, Jay A.; Smith, Dana; Reinisch, Lou

2000-05-01

Acute otitis media (AOM) remains a source of significant morbidity in children. With the emergence of antibiotic resistant strains of bacteria, tympanocentesis has become an important method of bacterial identification in the setting of treatment failures. Previous studies described a prototype system for the non-invasive fluorescence identification of bacteria in vitro. We demonstrate the addition of an optical fiber to allow for the identification of a specimen distant to the spectrofluorometer. Emission spectra from three bacteria, Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus were successfully obtained in vitro. This represents a necessary step prior to the study of in vivo identification of bacteria in AOM using fluorescence spectroscopy.

Constraints on mechanisms and rates of anaerobic oxidation of methane by microbial consortia: process-based modeling of ANME-2 archaea and sulfate reducing bacteria interactions

NASA Astrophysics Data System (ADS)

Orcutt, B.; Meile, C.

2008-11-01

Anaerobic oxidation of methane (AOM) is the main process responsible for the removal of methane generated in Earth's marine subsurface environments. However, the biochemical mechanism of AOM remains elusive. By explicitly resolving the observed spatial arrangement of methanotrophic archaea and sulfate reducing bacteria found in consortia mediating AOM, potential intermediates involved in the electron transfer between the methane oxidizing and sulfate reducing partners were investigated via a consortium-scale reaction transport model that integrates the effect of diffusional transport with thermodynamic and kinetic controls on microbial activity. Model simulations were used to assess the impact of poorly constrained microbial characteristics such as minimum energy requirements to sustain metabolism and cell specific rates. The role of environmental conditions such as the influence of methane levels on the feasibility of H2, formate and acetate as intermediate species, and the impact of the abundance of intermediate species on pathway reversal were examined. The results show that higher production rates of intermediates via AOM lead to increased diffusive fluxes from the methane oxidizing archaea to sulfate reducing bacteria, but the build-up of the exchangeable species can cause the energy yield of AOM to drop below that required for ATP production. Comparison to data from laboratory experiments shows that under the experimental conditions of Nauhaus et al. (2007), none of the potential intermediates considered here is able to support metabolic activity matching the measured rates.

Idler-resonant intracavity KTA-based OPO pumped by a dual-loss modulated-Q-switched-laser with AOM and Cr4+:YAG

NASA Astrophysics Data System (ADS)

Qiao, Junpeng; Zhao, Shengzhi; Yang, Kejian; Zhao, Jia; Li, Guiqiu; Li, Dechun; Li, Tao; Qiao, Wenchao

2017-06-01

An idler-resonant KTiOAsO4 (KTA)-based intracavity optical parametric oscillator (IOPO) pumped by a dual-loss-modulated Q-switched laser with an acousto-optic modulator (AOM) and a Cr4+:YAG saturable absorber (Cr4+:YAG-SA) has been presented. By utilizing a type-II non-critically phase-matched KTA crystal, signal wave at 1535 nm and idler wave at 3467 nm have been generated. Under an incident pump power of 18.3 W, maximum output powers of 615 mW for signal wave and 228 mW for idler wave were obtained at an AOM modulation rate of 10 kHz, corresponding to a whole optical-to-optical conversion efficiency of 4.6%. The shortest pulse widths of signal and idler wave were measured to be 898 ps and 2.9 ns, corresponding to the highest peak powers of 68.4 and 7.9 kW, respectively. In comparison with IOPO pumped by a singly Q-switched laser with an AOM, the IOPO pumped by a doubly Q-switched laser (DIOPO) with an AOM and a Cr4+:YAG-SA can generate signal wave and idler wave with shorter pulse width and higher peak power. By considering the spatial Gaussian distribution of intracavity photon density, a set of coupled rate equations for the idler-resonant DIOPO were built for the first time to the best of our knowledge. The simulation results agreed well with the experimental results.

Emission and oxidation of methane in a meromictic, eutrophic and temperate lake (Dendre, Belgium).

PubMed

Roland, Fleur A E; Darchambeau, François; Morana, Cédric; Bouillon, Steven; Borges, Alberto V

2017-02-01

We sampled the water column of the Dendre stone pit lake (Belgium) in spring, summer, autumn and winter. Depth profiles of several physico-chemical variables, nutrients, dissolved gases (CO 2 , CH 4 , N 2 O), sulfate, sulfide, iron and manganese concentrations and δ 13 C-CH4 were determined. We performed incubation experiments to quantify CH 4 oxidation rates, with a focus on anaerobic CH 4 oxidation (AOM), without and with an inhibitor of sulfate reduction (molybdate). The evolution of nitrate and sulfate concentrations during the incubations was monitored. The water column was anoxic below 20 m throughout the year, and was thermally stratified in summer and autumn. High partial pressure of CO 2 and CH 4 and high concentrations of ammonium and phosphate were observed in anoxic waters. Important nitrous oxide and nitrate concentration maxima were also observed (up to 440 nmol L -1 and 80 μmol L -1 , respectively). Vertical profiles of δ 13 C-CH 4 unambiguously showed the occurrence of AOM. Important AOM rates (up to 14 μmol L -1  d -1 ) were observed and often co-occurred with nitrate consumption peaks, suggesting the occurrence of AOM coupled with nitrate reduction. AOM coupled with sulfate reduction also occurred, since AOM rates tended to be lower when molybdate was added. CH 4 oxidation was mostly aerobic (∼80% of total oxidation) in spring and winter, and almost exclusively anaerobic in summer and autumn. Despite important CH 4 oxidation rates, the estimated CH 4 fluxes from the water surface to the atmosphere were high (mean of 732 μmol m -2  d -1 in spring, summer and autumn, and up to 12,482 μmol m -2  d -1 in winter). Copyright © 2016 Elsevier Ltd. All rights reserved.

Ghrelin administration suppresses inflammation-associated colorectal carcinogenesis in mice

PubMed Central

Kawaguchi, Makiko; Kanemaru, Ai; Fukushima, Tsuyoshi; Yamamoto, Koji; Tanaka, Hiroyuki; Haruyama, Yukihiro; Itoh, Hiroshi; Matsumoto, Nobuhiro; Kangawa, Kenji; Nakazato, Masamitsu; Kataoka, Hiroaki

2015-01-01

Ghrelin is a 28-amino-acid peptide that stimulates the release of pituitary growth hormone. Because of its orexigenic effects, ghrelin is being developed as a therapeutic option for postoperative support and treatment of anorexia-cachexia syndrome of cancer patients. However, ghrelin has a multiplicity of physiological functions, and it also affects cell proliferation. Therefore, the effects of ghrelin administration on carcinogenesis and cancer progression in patients susceptible to cancer should be clarified. In this study, we examined the effects of ghrelin on cancer promotion in vivo using murine intestinal carcinogenesis models. Intestinal tumorigenesis was examined to determine the effects of either exogenous ghrelin administration or ghrelin deficiency following deletion of the Ghrl gene. Two murine intestinal tumorigenesis models were used. The first was the azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced inflammation-associated colon carcinogenesis model and the second was the ApcMin/+ genetic cancer susceptibility model. In AOM/DSS-treated mice, administration of ghrelin significantly suppressed tumor formation in the colon. In contrast, ghrelin administration did not affect the number of intestinal tumors formed in ApcMin/+ mice. The absence of endogenous ghrelin did not affect the incidence of intestinal tumors in either AOM/DSS-treated mice or ApcMin/+ mice, though tumor size tended to be larger in Ghrl−/− colons in the AOM/DSS model. No tumor-promoting effect was observed by ghrelin administration in either tumorigenesis model. In summary, this study provides in vivo experimental evidence for the usefulness of ghrelin administration in the chemoprevention of inflammation-associated colorectal carcinogenesis and may suggest its safety in patients under colitis-associated cancer susceptibility conditions. PMID:26094822

Assessing sulfate reduction and methane cycling in a high salinity pore water system in the northern Gulf of Mexico

USGS Publications Warehouse

Pohlman, J.W.; Ruppel, C.; Hutchinson, D.R.; Downer, R.; Coffin, R.B.

2008-01-01

Pore waters extracted from 18 piston cores obtained on and near a salt-cored bathymetric high in Keathley Canyon lease block 151 in the northern Gulf of Mexico contain elevated concentrations of chloride (up to 838 mM) and have pore water chemical concentration profiles that exhibit extensive departures (concavity) from steady-state (linear) diffusive equilibrium with depth. Minimum ??13C dissolved inorganic carbon (DIC) values of -55.9??? to -64.8??? at the sulfate-methane transition (SMT) strongly suggest active anaerobic oxidation of methane (AOM) throughout the study region. However, the nonlinear pore water chemistry-depth profiles make it impossible to determine the vertical extent of active AOM or the potential role of alternate sulfate reduction pathways. Here we utilize the conservative (non-reactive) nature of dissolved chloride to differentiate the effects of biogeochemical activity (e.g., AOM and/or organoclastic sulfate reduction) relative to physical mixing in high salinity Keathley Canyon sediments. In most cases, the DIC and sulfate concentrations in pore waters are consistent with a conservative mixing model that uses chloride concentrations at the seafloor and the SMT as endmembers. Conservative mixing of pore water constituents implies that an undetermined physical process is primarily responsible for the nonlinearity of the pore water-depth profiles. In limited cases where the sulfate and DIC concentrations deviated from conservative mixing between the seafloor and SMT, the ??13C-DIC mixing diagrams suggest that the excess DIC is produced from a 13C-depleted source that could only be accounted for by microbial methane, the dominant form of methane identified during this study. We conclude that AOM is the most prevalent sink for sulfate and that it occurs primarily at the SMT at this Keathley Canyon site.

[Efficiency of combination therapy for acute otitis media].

PubMed

Poliakova, S D; Nekrasova, E A

2010-01-01

The clinical efficiency of treatment was evaluated in 60 patients aged 18 to 60 years with protracted acute otitis media (AOM) who had residual tympanic membrane inflammation and exudates in the tympanic cavity. The patients were divided into 2 groups of 30 each, who received equal basic medical treatment; Group 1 patients were additionally given eurespal (fenspiride) 80 mg thrice daily for 2 weeks. The patients were examined by clinical, endoscopic, and audiometric studies; the transport function of the nasal ciliated epithelium was also explored. The findings suggest the benefits of the additional use of eurespal in the treatment of the catarrhal stage of AOM.

Kenaf seed supercritical fluid extract reduces aberrant crypt foci formation in azoxymethane-induced rats.

PubMed

Ghafar, Siti Aisyah Abd; Yazan, Latifah Saiful; Tahir, Paridah Md; Ismail, Maznah

2012-03-01

Kenaf (Hibiscus cannabinus) a plant of the family Malvaceae, is a valuable fiber plant native to India and Africa. Kenaf seeds contain alpha-linolenic acid, phytosterol such as β-sitosterol, vitamin E and other antioxidants with chemopreventive properties. In the present study we examined the hypothesis that kenaf seed 'supercritical fluid extract' (SFE) extract could suppress the early colon carcinogenesis in vivo by virtue of its bioactive compounds. To accomplish this goal, 60 male rats were randomly assigned to 5 groups which were (1) negative control group [not induced with azoxymethane (AOM)]; (2) positive control group (induced with AOM but received no treatment); (3) group treated with 500 mg/kg kenaf seed SFE extract; (4) group treated with 1000 mg/kg kenaf seed SFE extract; (5) group treated with 1500 mg/kg kenaf seed SFE extract. At 7 weeks of age, all rats except the negative control group received 15 mg/kg of AOM injection subcutaneously once a week for 2 weeks. Rats were euthanized at 13 weeks of the experiment. Number of ACF (mean±SD) ranged from 84.4±4.43 to 179.5±12.78 in group 2, 3, 4, 5. ACF reductions compared with the untreated group were 45.3, 51.4 and 53.1% in rats fed with 500, 1000 and 1500 mg/kg body weight, respectively. There were no significant differences in weight gain among groups. Our finding indicates that kenaf seed SFE extract reduced AOM-induced ACF in Sprague-Dawley male rats. Copyright © 2010 Elsevier GmbH. All rights reserved.

Constraints on mechanisms and rates of anaerobic oxidation of methane by microbial consortia: process-based modeling of ANME-2 archaea and sulfate reducing bacteria interactions

NASA Astrophysics Data System (ADS)

Orcutt, B.; Meile, C.

2008-05-01

Anaerobic oxidation of methane (AOM) is the main process responsible for the removal of methane generated in Earth's marine subsurface environments. However, the biochemical mechanism of AOM remains elusive. By explicitly resolving the observed spatial arrangement of methanotrophic archaea and sulfate reducing bacteria found in consortia mediating AOM, potential intermediates involved in the electron transfer between the methane oxidizing and sulfate reducing partners were investigated via a consortium-scale reaction transport model that integrates the effect of diffusional transport with thermodynamic and kinetic controls on microbial activity. Model simulations were used to assess the impact of poorly constrained microbial characteristics such as minimum energy requirements to sustain metabolism, substrate affinity and cell specific rates. The role of environmental conditions such as the influence of methane levels on the feasibility of H2, formate and acetate as intermediate species, and the impact of the abundance of intermediate species on pathway reversal was examined. The results show that higher production rates of intermediates via AOM lead to increased diffusive fluxes from the methane oxidizing archaea to sulfate reducing bacteria, but the build-up of the exchangeable species causes the energy yield of AOM to drop below that required for ATP production. Comparison to data from laboratory experiments shows that under the experimental conditions of Nauhaus et al. (2007), neither hydrogen nor formate is exchanged fast enough between the consortia partners to achieve measured rates of metabolic activity, but that acetate exchange might support rates that approach those observed.

Antibiotics for acute otitis media in children.

PubMed

Venekamp, Roderick P; Sanders, Sharon L; Glasziou, Paul P; Del Mar, Chris B; Rovers, Maroeska M

2015-06-23

Acute otitis media (AOM) is one of the most common diseases in early infancy and childhood. Antibiotic use for AOM varies from 56% in the Netherlands to 95% in the USA, Canada and Australia. This is an update of a Cochrane review first published in The Cochrane Library in Issue 1, 1997 and previously updated in 1999, 2005, 2009 and 2013. To assess the effects of antibiotics for children with AOM. We searched CENTRAL (2015, Issue 3), MEDLINE (1966 to April week 3, 2015), OLDMEDLINE (1958 to 1965), EMBASE (January 1990 to April 2015), Current Contents (1966 to April 2015), CINAHL (2008 to April 2015) and LILACS (2008 to April 2015). Randomised controlled trials (RCTs) comparing 1) antimicrobial drugs with placebo and 2) immediate antibiotic treatment with expectant observation (including delayed antibiotic prescribing) in children with AOM. Two review authors independently assessed trial quality and extracted data. For the review of antibiotics against placebo, 13 RCTs (3401 children and 3938 AOM episodes) from high-income countries were eligible and had generally low risk of bias. The combined results of the trials revealed that by 24 hours from the start of treatment, 60% of the children had recovered whether or not they had placebo or antibiotics. Pain was not reduced by antibiotics at 24 hours (risk ratio (RR) 0.89, 95% confidence interval (CI) 0.78 to 1.01) but almost a third fewer had residual pain at two to three days (RR 0.70, 95% CI 0.57 to 0.86; number needed to treat for an additional beneficial outcome (NNTB) 20). A quarter fewer had pain at four to seven days (RR 0.76, 95% CI 0.63 to 0.91; NNTB 16) and two-thirds fewer had pain at 10 to 12 days (RR 0.33, 95% CI 0.17 to 0.66; NNTB 7) compared with placebo. Antibiotics did reduce the number of children with abnormal tympanometry findings at two to four weeks (RR 0.82, 95% CI 0.74 to 0.90; NNTB 11), at six to eight weeks (RR 0.88, 95% CI 0.78 to 1.00; NNTB 16) and the number of children with tympanic membrane perforations (RR 0.37, 95% CI 0.18 to 0.76; NNTB 33) and halved contralateral otitis episodes (RR 0.49, 95% CI 0.25 to 0.95; NNTB 11) compared with placebo. However, antibiotics neither reduced the number of children with abnormal tympanometry findings at three months (RR 0.97, 95% CI 0.76 to 1.24) nor the number of children with late AOM recurrences (RR 0.93, 95% CI 0.78 to 1.10) when compared with placebo. Severe complications were rare and did not differ between children treated with antibiotics and those treated with placebo. Adverse events (such as vomiting, diarrhoea or rash) occurred more often in children taking antibiotics (RR 1.38, 95% CI 1.19 to 1.59; number needed to treat for an additional harmful outcome (NNTH) 14). Funnel plots do not suggest publication bias. Individual patient data meta-analysis of a subset of included trials found antibiotics to be most beneficial in children aged less than two years with bilateral AOM, or with both AOM and otorrhoea.For the review of immediate antibiotics against expectant observation, five trials (1149 children) from high-income countries were eligible and had low to moderate risk of bias. Four trials (1007 children) reported outcome data that could be used for this review. From these trials, data from 959 children could be extracted for the meta-analysis of pain at three to seven days. No difference in pain was detectable at three to seven days (RR 0.75, 95% CI 0.50 to 1.12). One trial (247 children) reported data on pain at 11 to 14 days. Immediate antibiotics were not associated with a reduction in the number of children with pain (RR 0.91, 95% CI 0.75 to 1.10) compared with expectant observation. Additionally, no differences in the number of children with abnormal tympanometry findings at four weeks, tympanic membrane perforations and AOM recurrence were observed between groups. No serious complications occurred in either the antibiotic or the expectant observation group. Immediate antibiotics were associated with a substantial increased risk of vomiting, diarrhoea or rash compared with expectant observation (RR 1.71, 95% CI 1.24 to 2.36; NNTH 9).Results from an individual patient data meta-analysis including data from six high-quality trials (1643 children) that were also included as individual trials in our review showed that antibiotics seem to be most beneficial in children younger than two years of age with bilateral AOM (NNTB 4) and in children with both AOM and otorrhoea (NNTB 3). This review reveals that antibiotics have no early effect on pain, a slight effect on pain in the days following and only a modest effect on the number of children with tympanic perforations, contralateral otitis episodes and abnormal tympanometry findings at two to four weeks and at six to eight weeks compared with placebo in children with AOM. In high-income countries, most cases of AOM spontaneously remit without complications. The benefits of antibiotics must be weighed against the possible harms: for every 14 children treated with antibiotics one child experienced an adverse event (such as vomiting, diarrhoea or rash) that would not have occurred if antibiotics were withheld. Therefore clinical management should emphasise advice about adequate analgesia and the limited role for antibiotics. Antibiotics are most useful in children under two years of age with bilateral AOM, or with both AOM and otorrhoea. For most other children with mild disease in high-income countries, an expectant observational approach seems justified.

Methane emission and consumption at a North Sea gas seep (Tommeliten area)

NASA Astrophysics Data System (ADS)

Niemann, H.; Elvert, M.; Hovland, M.; Orcutt, B.; Judd, A.; Suck, I.; Gutt, J.; Joye, S.; Damm, E.; Finster, K.; Boetius, A.

2005-11-01

The North Sea hosts large coal, oil and gas reservoirs of commercial value. Natural leakage pathways of subsurface gas to the hydrosphere have been recognized during geological surveys (Hovland and Judd, 1988). The Tommeliten seepage area is part of the Greater Ekofisk area, which is situated above the Tommeliten Delta salt diapir in the central North Sea. In this study, we report of an active seep site (56°29.90'N, 2°59.80'E) located in the Tommeliten area, Norwegian Block 1/9, at 75 m water depth. Here, cracks in a buried marl horizon allow methane to migrate into overlying clay-silt and sandy sediments. Hydroacoustic sediment echosounding showed several venting spots coinciding with the apex of marl domes where methane is released into the water column and potentially to the atmosphere during deep mixing situations. In the vicinity of the gas seeps, sea floor observations showed small mats of giant sulphide-oxidizing bacteria above patches of black sediments and carbonate crusts, which are exposed 10 to 50 cm above seafloor forming small reefs. These Methane-Derived Authigenic Carbonates (MDACs) contain 13C-depleted, archaeal lipids indicating previous gas seepage and AOM activity. High amounts of sn2-hydroxyarchaeol relative to archaeol and low abundances of biphytanes in the crusts give evidence that ANaerobic MEthane-oxidising archaea (ANME) of the phylogenetic cluster ANME-2 were the potential mediators of Anaerobic Oxidation of Methane (AOM) at the time of carbonate formation. Small pieces of MDACs were also found subsurface at about 1.7 m sediment depth, associated with the Sulphate-Methane Transition Zone (SMTZ). The SMTZ of Tommeliten is characterized by elevated AOM and Sulphate Reduction (SR) rates, increased concentrations of 13C-depleted tetraether derived biphytanes, and specific bacterial Fatty Acids (FA). Further biomarker and 16S rDNA based analyses give evidence that AOM at the Tommeliten SMTZ is mediated by archaea belonging to the ANME-1b group and Sulphate Reducing Bacteria (SRB) most likely belonging to the Seep-SRB1 cluster. The zone of active methane consumption was restricted to a distinct horizon of about 20 cm. Concentrations of 13C-depleted lipid biomarkers (e.g. 500 ng g-dw-1 biphythanes, 140 ng g-dw-1 fatty acid ai-C15:0), cell numbers (1.5x108 cells cm-3), AOM and SR rates (3 nmol cm-3 d-1 in the SMTZ are 2-3 orders of magnitude lower compared to AOM zones of highly active cold seeps such as Hydrate Ridge or the Gulf of Mexico.

Amoxicillin/clavulanic acid: a review of its use in the management of paediatric patients with acute otitis media.

PubMed

Easton, Jane; Noble, Stuart; Perry, Caroline M

2003-01-01

Amoxicillin/clavulanic acid (Augmentin), Augmentin ES-600 is a well established, orally administered combination of amoxicillin (a semisynthetic antibacterial agent) and clavulanic acid (a beta-lactamase inhibitor). Amoxicillin/clavulanic acid shows good activity against the main pathogens associated with acute otitis media (AOM), including penicillin-susceptible and -intermediate strains of Streptococcus pneumoniae, and beta-lactamase producing strains of Haemophilus influenzae and Moraxella catarrhalis. It has moderate activity against penicillin-resistant S. pneumoniae; a high-dose formulation has been developed with the aim of providing better coverage for penicillin-resistant strains. Amoxicillin/clavulanic acid (conventional formulations, mostly 40/10 mg/kg/day in three divided doses) produced clinical response rates similar to those of oral cephalosporin comparators and similar to or significantly greater than those for intramuscular ceftriaxone in randomised trials in paediatric patients with AOM (mean age approximately 2 to 5 years). Clinical response rates were generally similar for amoxicillin/clavulanic acid and macrolide comparators (mean patient age approximately 1 to 6 years), although significantly better clinical and bacteriological responses were seen versus azithromycin in one randomised trial (mean patient age approximately 1 year). The high-dose formulation of amoxicillin/clavulanic acid (90/6.4 mg/kg/day in two divided doses) eradicated a high proportion of penicillin-resistant S. pneumoniae (penicillin MICs 2 or 4 mg/L) in a large noncomparative trial in children with AOM (upper limit of the US indication for S. pneumoniae is 2 mg/L). Amoxicillin/clavulanic acid is generally well tolerated. A low total incidence of adverse events (3.6%) and no serious events were reported from a large paediatric postmarketing study. The most frequently reported adverse events in children are mild gastrointestinal disturbances. Diarrhoea is generally less frequent with twice-daily than with three-times-daily treatment. The new high-dose formulation showed similar tolerability to a conventional twice-daily formulation (45/6.4 mg/kg/day) in a well controlled trial. Amoxicillin/clavulanic acid is a well established broad-spectrum antibacterial treatment which is effective and well tolerated in the treatment of AOM in paediatric patients. The high-dose combination should prove valuable in treating AOM caused by penicillin-intermediate and -resistant S. pneumoniae (approved in the US for penicillin MIC < or =2 mg/L). Based on recent recommendations and the available data, high-dose amoxicillin/clavulanic acid can be considered a treatment of choice for recurrent or persistent paediatric AOM (after failure of amoxicillin alone) where involvement of resistant pathogens is suspected.

AOM/DSS Model of Colitis-Associated Cancer

PubMed Central

Parang, Bobak; Barret, Caitlyn W.; Williams, Christopher S.

2016-01-01

Summary Our understanding of colitis-associated carcinoma (CAC) has benefited substantially from mouse models that faithfully recapitulate human CAC. Chemical models, in particular, have enabled fast and efficient analysis of genetic and environmental modulators of CAC without the added requirement of time-intensive genetic crossings. Here we describe the Azoxymethane (AOM)/Dextran Sodium Sulfate (DSS) mouse model of inflammatory colorectal cancer. PMID:27246042

A Long-Term Cultivation of an Anaerobic Methane-Oxidizing Microbial Community from Deep-Sea Methane-Seep Sediment Using a Continuous-Flow Bioreactor

PubMed Central

Aoki, Masataka; Ehara, Masayuki; Saito, Yumi; Yoshioka, Hideyoshi; Miyazaki, Masayuki; Saito, Yayoi; Miyashita, Ai; Kawakami, Shuji; Yamaguchi, Takashi; Ohashi, Akiyoshi; Nunoura, Takuro; Takai, Ken; Imachi, Hiroyuki

2014-01-01

Anaerobic oxidation of methane (AOM) in marine sediments is an important global methane sink, but the physiological characteristics of AOM-associated microorganisms remain poorly understood. Here we report the cultivation of an AOM microbial community from deep-sea methane-seep sediment using a continuous-flow bioreactor with polyurethane sponges, called the down-flow hanging sponge (DHS) bioreactor. We anaerobically incubated deep-sea methane-seep sediment collected from the Nankai Trough, Japan, for 2,013 days in the bioreactor at 10°C. Following incubation, an active AOM activity was confirmed by a tracer experiment using 13C-labeled methane. Phylogenetic analyses demonstrated that phylogenetically diverse Archaea and Bacteria grew in the bioreactor. After 2,013 days of incubation, the predominant archaeal components were anaerobic methanotroph (ANME)-2a, Deep-Sea Archaeal Group, and Marine Benthic Group-D, and Gammaproteobacteria was the dominant bacterial lineage. Fluorescence in situ hybridization analysis showed that ANME-1 and -2a, and most ANME-2c cells occurred without close physical interaction with potential bacterial partners. Our data demonstrate that the DHS bioreactor system is a useful system for cultivating fastidious methane-seep-associated sedimentary microorganisms. PMID:25141130

Deflecting light into resonant cavities for spectroscopy

DOEpatents

Zare, R.N.; Martin, J.; Paldus, B.A.

1998-09-29

Light is coupled into a cavity ring down spectroscopy (CRDS) resonant cavity using an acousto-optic modulator. The AOM allows in-coupling efficiencies in excess of 40%, which is two to three orders of magnitude higher than in conventional systems using a cavity mirror for in-coupling. The AOM shutoff time is shorter than the roundtrip time of the cavity. The higher light intensities lead to a reduction in shot noise, and allow the use of relatively insensitive but fast-responding detectors such as photovoltaic detectors. Other deflection devices such as electro-optic modulators or elements used in conventional Q-switching may be used instead of the AOM. The method is particularly useful in the mid-infrared, far-infrared, and ultraviolet wavelength ranges, for which moderately reflecting input mirrors are not widely available. 5 figs.

Deflecting light into resonant cavities for spectroscopy

DOEpatents

Zare, Richard N.; Martin, Juergen; Paldus, Barbara A.

1998-01-01

Light is coupled into a cavity ring down spectroscopy (CRDS) resonant cavity using an acousto-optic modulator. The AOM allows in-coupling efficiencies in excess of 40%, which is two to three orders of magnitude higher than in conventional systems using a cavity mirror for in-coupling. The AOM shutoff time is shorter than the roundtrip time of the cavity. The higher light intensities lead to a reduction in shot noise, and allow the use of relatively insensitive but fast-responding detectors such as photovoltaic detectors. Other deflection devices such as electro-optic modulators or elements used in conventional Q-switching may be used instead of the AOM. The method is particularly useful in the mid-infrared, far-infrared, and ultraviolet wavelength ranges, for which moderately reflecting input mirrors are not widely available.

Neuronal CCL2 is upregulated during hepatic encephalopathy and contributes to microglia activation and neurological decline

PubMed Central

2014-01-01

Background Acute liver failure leads to systemic complications with one of the most dangerous being a decline in neurological function, termed hepatic encephalopathy. Neurological dysfunction is exacerbated by an increase of toxic metabolites in the brain that lead to neuroinflammation. Following various liver diseases, hepatic and circulating chemokines, such as chemokine ligand 2 (CCL2), are elevated, though their effects on the brain following acute liver injury and subsequent hepatic encephalopathy are unknown. CCL2 is known to activate microglia in other neuropathies, leading to a proinflammatory response. However, the effects of CCL2 on microglia activation and the pathogenesis of hepatic encephalopathy following acute liver injury remain to be determined. Methods Hepatic encephalopathy was induced in mice via injection of azoxymethane (AOM) in the presence or absence of INCB 3284 dimesylate (INCB), a chemokine receptor 2 inhibitor, or C 021 dihydrochloride (C021), a chemokine receptor 4 inhibitor. Mice were monitored for neurological decline and time to coma (loss of all reflexes) was recorded. Tissue was collected at coma and used for real-time PCR, immunoblots, ELISA, or immunostaining analyses to assess the activation of microglia and consequences on pro-inflammatory cytokine expression. Results Following AOM administration, microglia activation was significantly increased in AOM-treated mice compared to controls. Concentrations of CCL2 in the liver, serum, and cortex were significantly elevated in AOM-treated mice compared to controls. Systemic administration of INCB or C021 reduced liver damage as assessed by serum liver enzyme biochemistry. Administration of INCB or C021 significantly improved the neurological outcomes of AOM-treated mice, reduced microglia activation, reduced phosphorylation of ERK1/2, and alleviated AOM-induced cytokine upregulation. Conclusions These findings suggest that CCL2 is elevated systemically following acute liver injury and that CCL2 is involved in both the microglia activation and neurological decline associated with hepatic encephalopathy. Methods used to modulate CCL2 levels and/or reduce CCR2/CCR4 activity may be potential therapeutic targets for the management of hepatic encephalopathy due to acute liver injury. PMID:25012628

Neuronal CCL2 is upregulated during hepatic encephalopathy and contributes to microglia activation and neurological decline.

PubMed

McMillin, Matthew; Frampton, Gabriel; Thompson, Michelle; Galindo, Cheryl; Standeford, Holly; Whittington, Eric; Alpini, Gianfranco; DeMorrow, Sharon

2014-07-10

Acute liver failure leads to systemic complications with one of the most dangerous being a decline in neurological function, termed hepatic encephalopathy. Neurological dysfunction is exacerbated by an increase of toxic metabolites in the brain that lead to neuroinflammation. Following various liver diseases, hepatic and circulating chemokines, such as chemokine ligand 2 (CCL2), are elevated, though their effects on the brain following acute liver injury and subsequent hepatic encephalopathy are unknown. CCL2 is known to activate microglia in other neuropathies, leading to a proinflammatory response. However, the effects of CCL2 on microglia activation and the pathogenesis of hepatic encephalopathy following acute liver injury remain to be determined. Hepatic encephalopathy was induced in mice via injection of azoxymethane (AOM) in the presence or absence of INCB 3284 dimesylate (INCB), a chemokine receptor 2 inhibitor, or C 021 dihydrochloride (C021), a chemokine receptor 4 inhibitor. Mice were monitored for neurological decline and time to coma (loss of all reflexes) was recorded. Tissue was collected at coma and used for real-time PCR, immunoblots, ELISA, or immunostaining analyses to assess the activation of microglia and consequences on pro-inflammatory cytokine expression. Following AOM administration, microglia activation was significantly increased in AOM-treated mice compared to controls. Concentrations of CCL2 in the liver, serum, and cortex were significantly elevated in AOM-treated mice compared to controls. Systemic administration of INCB or C021 reduced liver damage as assessed by serum liver enzyme biochemistry. Administration of INCB or C021 significantly improved the neurological outcomes of AOM-treated mice, reduced microglia activation, reduced phosphorylation of ERK1/2, and alleviated AOM-induced cytokine upregulation. These findings suggest that CCL2 is elevated systemically following acute liver injury and that CCL2 is involved in both the microglia activation and neurological decline associated with hepatic encephalopathy. Methods used to modulate CCL2 levels and/or reduce CCR2/CCR4 activity may be potential therapeutic targets for the management of hepatic encephalopathy due to acute liver injury.

Bioenergetic and Geobiological Possibilities of Methanotrophy on Mars

NASA Astrophysics Data System (ADS)

Marlow, J. J.; LaRowe, D.; Ehlmann, B. L.; Amend, J.; Orphan, V. J.

2014-12-01

During its ancient past, Mars exhibited dynamic conditions that facilitated water-rock reactions, bringing unequilibrated chemical constituents into contact with each other. Such interactions have prompted speculation regarding the energetic output of redox reactions. The sulfate-driven anaerobic oxidation of methane (AOM) is one redox reaction that has not been carefully investigated in an ancient martian context, and yet, with recent reports of methane and sulfate-bearing minerals on Mars, it may be one of the more observationally constrained options for a putative metabolism. In this work, we evaluate the Gibbs energies of the AOM metabolism under a range of atmospheric compositions using seven putative martian groundwater compositions. In all scenarios, AOM is exergonic, ranging from -31 to -135 kJ/mol CH4. A reaction transport model was developed to incorporate the advection and diffusion of nutrients, reaction rates, and the feedback between growing organisms' nutrient consumption and downstream concentrations. The extent of crustal volume under exergonic conditions is set primarily by localized reactant concentration, while relative changes within the exergonic zone are driven primarily by product accumulation. In order for AOM to have been an energetically viable metabolism on ancient Mars, co-located reactants would have been necessary. At NE Syrtis Major, serpentinization of the olivine-bearing unit may have produced hydrogen, which could generate methane in the abiotic reduction of CO2. In the overlying jarosite-bearing layer, sulfate and incoming methane provide the reactants for AOM. An alternative scenario for martian AOM involves methane production by subsurface hydrothermal alteration of basaltic crust, and acid sulfate conditions are produced from fluids derived near the surface. Sulfate-bearing waters are formed by aerosol deposition and subsequent dissolution of oxidized sulfur species by water. Finally, continuing work on constraining martian reaction transport models from a microbiological perspective will be discussed. Understanding which parameters can be refined based on orbital or rover observations will aid in producing site-specific models that will help inform the search for signs of past or present life beneath the martian surface.

Modeling sulfate reduction in methane hydrate-bearing continental margin sediments: Does a sulfate-methane transition require anaerobic oxidation of methane?

USGS Publications Warehouse

Malinverno, A.; Pohlman, J.W.

2011-01-01

The sulfate-methane transition (SMT), a biogeochemical zone where sulfate and methane are metabolized, is commonly observed at shallow depths (1-30 mbsf) in methane-bearing marine sediments. Two processes consume sulfate at and above the SMT, anaerobic oxidation of methane (AOM) and organoclastic sulfate reduction (OSR). Differentiating the relative contribution of each process is critical to estimate methane flux into the SMT, which, in turn, is necessary to predict deeper occurrences of gas hydrates in continental margin sediments. To evaluate the relative importance of these two sulfate reduction pathways, we developed a diagenetic model to compute the pore water concentrations of sulfate, methane, and dissolved inorganic carbon (DIC). By separately tracking DIC containing 12C and 13C, the model also computes ??13C-DIC values. The model reproduces common observations from methane-rich sediments: a well-defined SMT with no methane above and no sulfate below and a ??13C-DIC minimum at the SMT. The model also highlights the role of upward diffusing 13C-enriched DIC in contributing to the carbon isotope mass balance of DIC. A combination of OSR and AOM, each consuming similar amounts of sulfate, matches observations from Site U1325 (Integrated Ocean Drilling Program Expedition 311, northern Cascadia margin). Without AOM, methane diffuses above the SMT, which contradicts existing field data. The modeling results are generalized with a dimensional analysis to the range of SMT depths and sedimentation rates typical of continental margins. The modeling shows that AOM must be active to establish an SMT wherein methane is quantitatively consumed and the ??13C-DIC minimum occurs. The presence of an SMT generally requires active AOM. Copyright 2011 by the American Geophysical Union.

Improvement Rate of Acute Otitis Media Caused by Haemophilus influenzae at 1 Week Is Significantly Associated with Time to Recovery

PubMed Central

Yamazaki, Yoshitaka; Qin, Liang; Okitsu, Naohiro; Yahara, Koji; Irimada, Mihoko; Hirakata, Yoichi; Kaku, Mitsuo; Kobayashi, Toshimitsu; Watanabe, Hiroshi

2013-01-01

Acute otitis media (AOM) is the most common upper respiratory tract infection in childhood. Children with AOM were enrolled at Tohoku Rosai Hospital between July 2006 and June 2011 if their middle ear fluid cultures after tympanocentesis yielded only Haemophilus influenzae. The susceptibilities of the isolates to ampicillin were determined, and microtiter biofilm assays and invasion assays using BEAS-2B cells were performed. The association between these bacterial characteristics and clinical relapses of AOM and treatment failures was evaluated. Seventy-four children (39 boys and 35 girls) with a median age of 1 year (interquartile range [IQR], 0.25 to 2 years) were enrolled. Among 74 H. influenzae isolates, 37 showed intermediate resistance or resistance to ampicillin (MIC, ≥2 μg/ml). In the microtiter biofilm assay, the median optical density at 600 nm (OD600) was 0.68 (IQR, 0.24 to 1.02), and 70 isolates formed biofilms. The median invasion rate was 15% (IQR, 0 to 10%), and 46 isolates invaded BEAS-2B cells. Relapses and treatment failures occurred in 19 and 6 children, respectively. There was no significant difference in the invasion rates between patients with and those without relapses or treatment failures. Also, there was no significant association between biofilm formation and relapse or treatment failure. The improvements in the severity scores after 1 week were significantly associated with the recovery time (P < 0.0001). We did not identify any significant association between relapse or treatment failure and bacterial factors. AOM has a multifactorial etiology, and this may explain why we could not find a significant association. An improvement in the severity score after 1 week of treatment may be a useful predictor of the outcome of AOM. PMID:23966504

Prognostic Factors for Treatment Failure in Acute Otitis Media.

PubMed

Tähtinen, Paula A; Laine, Miia K; Ruohola, Aino

2017-09-01

Antimicrobial treatment is effective in the management of acute otitis media (AOM), but approximately half of the children may recover without antimicrobial agents. By identifying patients who may not require antimicrobial treatment for the management of AOM, the use of antimicrobial agents could be substantially reduced. Our aim was to identify subgroups of children with AOM who would benefit most from antimicrobial treatment and children who could be suitable for initial observation. This is a secondary analysis of randomized, double-blind, placebo-controlled trial. Children 6 to 35 months of age with AOM (N = 319) were randomly allocated to receive amoxicillin-clavulanate (40/5.7 mg/kg per day) or placebo for 7 days. Our primary outcome was time until treatment failure. Treatment failure occurred in 31.7% of all children. Older age (24-35 months) and peaked tympanogram at entry decreased the hazard for treatment failure (hazard ratio, 0.53; 95% confidence interval [CI], 0.29 to 0.96; P = .04; and hazard ratio, 0.43; 95% CI, 0.21 to 0.88; P = .02, respectively). The rate difference for treatment failure between antimicrobial treatment and placebo groups was highest among children with severe bulging of the tympanic membrane (11.1% vs 64.1%; rate difference -53.0%; 95% CI, -73.5% to -32.4%), resulting in a number needed to treat of 1.9. Children with severe bulging of the tympanic membrane seem to benefit most from antimicrobial treatment of AOM. On the other hand, children with peaked tympanogram (A and C curves) may be optimal candidates for initial observation. Copyright © 2017 by the American Academy of Pediatrics.

Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

PubMed

Nasuno, Masanao; Arimura, Yoshiaki; Nagaishi, Kanna; Isshiki, Hiroyuki; Onodera, Kei; Nakagaki, Suguru; Watanabe, Shuhei; Idogawa, Masashi; Yamashita, Kentaro; Naishiro, Yasuyoshi; Adachi, Yasushi; Suzuki, Hiromu; Fujimiya, Mineko; Imai, Kohzoh; Shinomura, Yasuhisa

2014-04-01

The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-β signaling because such properties were completely abrogated by absorption of TGF-β under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-β-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease. © AlphaMed Press.

Formation of regulated and unregulated disinfection byproducts during chlorination of algal organic matter extracted from freshwater and marine algae.

PubMed

Liu, Chao; Ersan, Mahmut S; Plewa, Michael J; Amy, Gary; Karanfil, Tanju

2018-05-29

Seasonal algal blooms in freshwater and marine water can increase the input of algal organic matter (AOM) to the pool of dissolved organic matter. The impact of bromide (Br - ) and iodide (I - ) on the formation of regulated and unregulated disinfection byproducts (DBPs) was studied from chlorination of AOM solutions extracted from three species of cultured isolates of freshwater and marine algae (Microcystis aeruginosa (MA), Synechococcus (SYN), and Alexandrium tamarense (AT)). Comparable concentrations of DBPs were formed from three types of AOM. In the absence of Br - , trihalomethanes (THMs), haloacetic acids (HAAs), and haloacetaldehydes (HALs) were the main groups of DBP formed, and haloacetonitriles (HANs) were formed at lower concentrations. In contrast, the formation of iodinated THMs was <8 nM (1.7 μg/L) since most of initial I - was oxidized to iodate. Increasing initial Br - concentrations increased the formation of THMs and HANs, while concentrations of total organic halogen and HAA remained stable. On the contrary, total HAL concentrations decreased due to the instability of bromated HALs. Decreasing the specific UV absorbance (SUVA) value of AOM favours bromine substitution since bromine more preferentially reacts with low reactivity organic matter than chlorine. Increasing the pH enhanced the formation of THMs but decreased the formation of HANs. Concentrations of HANs and HALs decreased at high pH (e.g., 9.0), high initial chlorine concentration and long reaction time due to the decomposition. Based on the cytotoxicity calculations, unregulated HANs and HALs were the main contributors for the total toxicity of DBPs measured, even though based on the weight regulated THMs and HAAs predominated. Copyright © 2018 Elsevier Ltd. All rights reserved.

Otitis media.

PubMed

Schilder, Anne G M; Chonmaitree, Tasnee; Cripps, Allan W; Rosenfeld, Richard M; Casselbrant, Margaretha L; Haggard, Mark P; Venekamp, Roderick P

2016-09-08

Otitis media (OM) or middle ear inflammation is a spectrum of diseases, including acute otitis media (AOM), otitis media with effusion (OME; 'glue ear') and chronic suppurative otitis media (CSOM). OM is among the most common diseases in young children worldwide. Although OM may resolve spontaneously without complications, it can be associated with hearing loss and life-long sequelae. In developing countries, CSOM is a leading cause of hearing loss. OM can be of bacterial or viral origin; during 'colds', viruses can ascend through the Eustachian tube to the middle ear and pave the way for bacterial otopathogens that reside in the nasopharynx. Diagnosis depends on typical signs and symptoms, such as acute ear pain and bulging of the tympanic membrane (eardrum) for AOM and hearing loss for OME; diagnostic modalities include (pneumatic) otoscopy, tympanometry and audiometry. Symptomatic management of ear pain and fever is the mainstay of AOM treatment, reserving antibiotics for children with severe, persistent or recurrent infections. Management of OME largely consists of watchful waiting, with ventilation (tympanostomy) tubes primarily for children with chronic effusions and hearing loss, developmental delays or learning difficulties. The role of hearing aids to alleviate symptoms of hearing loss in the management of OME needs further study. Insertion of ventilation tubes and adenoidectomy are common operations for recurrent AOM to prevent recurrences, but their effectiveness is still debated. Despite reports of a decline in the incidence of OM over the past decade, attributed to the implementation of clinical guidelines that promote accurate diagnosis and judicious use of antibiotics and to pneumococcal conjugate vaccination, OM continues to be a leading cause for medical consultation, antibiotic prescription and surgery in high-income countries.

"Heart Bone"--The Case for the IHI Open School as Connector: A Model for Integrating Quality Improvement and Patient Safety into Health Professions Curricula.

PubMed

Miller, Ryan J; Hoffman, Wendell W

2015-06-01

The physician is guardian of the patient and obligated to both the "Science of Medicine" (SOM), defined by the randomized controlled trial, and the "Art of Medicine" (AOM), defined by patient safety (PS) and quality improvement (QI). Historically SOM knowledge has dominated AOM knowledge; however given the frequency of medical harm, a new paradigm is necessary. The Institute for Healthcare Improvement Open School (IHIOS) is accelerating AOM into medical curricula by connecting all stakeholders to the emerging PS and QI sciences, and doing so in an interprofessional manner. A South Dakota IHIOS chapter was established in 2011, connecting SOM to AOM knowledge for 600 students from eight schools and thirteen disciplines. Four specific foci included 1) interprofessional pilot project introducing PS and QI into first year curricula, 2) sessions for third-year medical students to assess Open School courses through faculty-facilitated small groups, 3) development of longitudinal quality and safety curricula, 4) integration of OS courses across South Dakota health professions schools. The interprofessional pilot project demonstrated significant learning in 16 of 16 and 13 of 16 (p = 0.05) teaching points. The third-year sessions showed that PS and QI topics are viewed as important especially with faculty-facilitated case studies. Subsequently a longitudinal PS and QI curriculum was implemented. This led to the incorporation of IHIOS courses as core curricula in four South Dakota colleges and eight health disciplines. Our work was one of the first large-scale efforts to measure learning via the IHIOS through the novel use of the chapter as connector. The model contributes to national efforts for paradigm change through interprofessional education.

High power CO2 laser development with AOM integration for ultra high-speed pulses

NASA Astrophysics Data System (ADS)

Bohrer, Markus; Vaupel, Matthias; Nirnberger, Robert; Weinberger, Bernhard; Jamalieh, Murad

2017-01-01

There is a 500 billion USD world market for packaging expected to grow to a trillion in 2030. Austria plays an important role world wide for high speed laser engraving applications — especially when it comes to high end solutions. Such high end solutions are fundamental for the production of print forms for the packaging and decorating industry (e. g. cans). They are additionally used for security applications (e. g. for printing banknotes), for the textile printing industry and for creating embossing forms (e. g. for the production of dashboards in the automotive industry). High speed, high precision laser engraving needs laser resonators with very stable laser beams (400 - 800W) especially in combination with AOMs. Based upon a unique carbon fiber structure - stable within the sub-micrometer range - a new resonator has been developed, accompanied by most recent thermo-mechanical FEM calculations. The resulting beam is evaluated on an automated optical bench using hexapods, allowing to optimize the complete beam path with collimators and AOM. The major steps related to laser engraving of dry offset printing plates during the full workflow from the artists design to the printed result on an aluminum can is presented in this paper as well as laser characteristics, AOM integration and correlative CLSM and SEM investigation of the results.

Effects of Two Traditional Chinese Cooking Oils, Canola and Pork, on pH and Cholic Acid Content of Faeces and Colon Tumorigenesis in Kunming Mice.

PubMed

He, Xiao-Qiong; Duan, Jia-Li; Zhou, Jin; Song, Zhong-Yu; Cichello, Simon Angelo

2015-01-01

Faecal pH and cholate are two important factors that can affect colon tumorigenesis, and can be modified by diet. In this study, the effects of two Chinese traditional cooking oils (pork oil and canola/rapeseed oil) on the pH and the cholic acid content in feces, in addition to colon tumorigenesis, were studied in mice. Kunming mice were randomized into various groups; negative control group (NCG), azoxymethane control group (ACG), pork oil group (POG), and canola oil Ggroup (COG). Mice in the ACG were fed a basic rodent chow; mice in POG and COG were given 10% cooking oil rodent chow with the respective oil type. All mice were given four weekly AOM (azoxymethane) i.p. injections (10 mg/kg). The pH and cholic acid of the feces were examined every two weeks. Colon tumors, aberrant crypt foci and organ weights were examined 32 weeks following the final AOM injection. The results showed that canola oil significantly decreased faecal pH in female mice (P<0.05), but had no influence on feces pH in male mice (P>0.05). Pork oil significantly increased the feces pH in both male and female mice (P<0.05). No significant change was found in feces cholic acid content when mice were fed 10% pork oil or canola oil compared with the ACG. Although Kunming mice were not susceptible to AOM-induced tumorigenesis in terms of colon tumor incidence, pork oil significantly increased the ACF number in male mice. Canola oil showed no influence on ACF in either male or female mice. Our results indicate that cooking oil effects faecal pH, but does not affect the faecal cholic acid content and thus AOM-induced colon neoplastic ACF is modified by dietary fat.

Negligible Colon Cancer Risk from Food-Borne Acrylamide Exposure in Male F344 Rats and Nude (nu/nu) Mice-Bearing Human Colon Tumor Xenografts

PubMed Central

Raju, Jayadev; Roberts, Jennifer; Sondagar, Chandni; Kapal, Kamla; Aziz, Syed A.; Caldwell, Don; Mehta, Rekha

2013-01-01

Acrylamide, a possible human carcinogen, is formed in certain carbohydrate-rich foods processed at high temperature. We evaluated if dietary acrylamide, at doses (0.5, 1.0 or 2.0 mg/kg diet) reflecting upper levels found in human foods, modulated colon tumorigenesis in two rodent models. Male F344 rats were randomized to receive diets without (control) or with acrylamide. 2-weeks later, rats in each group received two weekly subcutaneous injections of either azoxymethane (AOM) or saline, and were killed 20 weeks post-injections; colons were assessed for tumors. Male athymic nude (nu/nu) mice bearing HT-29 human colon adenocarcinoma cells-derived tumor xenografts received diets without (control) or with acrylamide; tumor growth was monitored and mice were killed 4 weeks later. In the F344 rat study, no tumors were found in the colons of the saline-injected rats. However, the colon tumor incidence was 54.2% and 66.7% in the control and the 2 mg/kg acrylamide-treated AOM-injected groups, respectively. While tumor multiplicity was similar across all diet groups, tumor size and burden were higher in the 2 mg/kg acrylamide group compared to the AOM control. These results suggest that acrylamide by itself is not a “complete carcinogen”, but acts as a “co-carcinogen” by exacerbating the effects of AOM. The nude mouse study indicated no differences in the growth of human colon tumor xenografts between acrylamide-treated and control mice, suggesting that acrylamide does not aid in the progression of established tumors. Hence, food-borne acrylamide at levels comparable to those found in human foods is neither an independent carcinogen nor a tumor promoter in the colon. However, our results characterize a potential hazard of acrylamide as a colon co-carcinogen in association with known and possibly other environmental tumor initiators/promoters. PMID:24040114

Disinfection by-product formation during chlor(am)ination of algal organic matters (AOM) extracted from Microcystis aeruginosa: effect of growth phases, AOM and bromide concentration.

PubMed

Chen, Juxiang; Gao, Naiyun; Li, Lei; Zhu, Mingqiu; Yang, Jing; Lu, Xian; Zhang, Yansen

2017-03-01

Algae organic matter (AOM), including extracellular organic matter (EOM) and intracellular organic matter (IOM), has caused a series of problems to the water quality, among which formation of disinfection by-products (DBPs) during subsequent chlor(am)ination process was especially serious and concerned. This study characterized physicochemical properties of the EOM and IOM solution extracted from different growth phases of Microcystis aeruginosa and investigated the corresponding formation potential of DBPs during chlor(am)ination process. Besides, the effects of initial concentration of xEOM, IOM, and Br - on the yields of disinfection by-product formation potential were studied. The results indicated that the specific UV absorbance (SUVA 254 ) values of IOM and EOM (1.09 and 2.66 L/mg m) were considerably lower than that of natural organic matter (NOM) (4.79 L/mg m). Fluorescence dates showed the soluble microbial by-product was dominant in both EOM and IOM, and the tryptophan was the main component of AOM. From the excitation-emission matrix figure of EOM and IOM, we found that the content of the high molecular weight protein substance in IOM was higher than EOM. During chlorination of EOM and IOM, the yields of four kinds of DBPs followed the order trichloroethene (TCM) > 1,1-DCP > dichloride acetonitrile (DCAN) > trichloronitromethane (TCNM), while the order was TCM > DCAN > TCNM > 1,1-DCP during chloramination process. The bromine substitution factor (BSF) value increased with the increasing of the concentration of Br - . When the concentration of Br - was 500 μg/L, the BSF values of chlorination EOM and IOM were 51.1 and 68.4%, respectively. As the concentration of Br - increased, the formation of Cl-DBPs was inhibited and the formation of Br-DBPs was promoted. Graphical abstract ᅟ.

Anaerobic nitrite-dependent methane-oxidizing bacteria - novel participants in methane cycling of drained peatlands ecosystems

NASA Astrophysics Data System (ADS)

Kravchenko, Irina; Sukhacheva, Marina; Menko, Ekaterina; Sirin, Andrey

2014-05-01

Northern peatlands are one of the key sources of atmospheric methane. Process-based studies of methane dynamic are based on the hypothesis of the balance between microbial methane production and oxidation, but this doesn't explain all variations in and constraints on peatland CH4 emissions. One of the reasons for this discrepancy could be anaerobic methane oxidation (AOM) - the process which is still poorly studied and remained controversial. Very little is known about AOM in peatlands, where it could work as an important 'internal' sink for CH4. This lack of knowledge primarily originated from researchers who generally consider AOM quantitatively insignificant or even non-existent in northern peatland ecosystems. But not far ago, Smemo and Yavitt (2007) presented evidence for AOM in freshwater peatlands used indirect techniques including isotope dilution assays and selective methanogenic inhibitors. Nitrite-dependent anaerobic methane oxidation NC10 group bacteria (n-damo) were detected in a minerotrophic peatland in the Netherlands that is infiltrated by nitrate-rich ground water (Zhu et al., 2012). Present study represents the first, to our knowledge, characterization of AOM in human disturbed peatlands, including hydrological elements of artificial drainage network. The experiments were conducted with samples of peat from drained peatlands, as well as of water and bottom sediments of ditches from drained Dubnensky mire massif, Moscow region (Chistotin et al., 2006; Sirin et al., 2012). This is the key testing area of our research group in European part of Russia for the long-term greenhouse gases fluxes measurements supported by testing physicochemical parameters, intensity and genomic diversity of CH4-cycling microbial communities. Only in sediments of drainage ditches the transition anaerobic zone was found, where methane and nitrate occurred, suggested the possible ecological niche for n-damo bacteria. The NC10 group methanotrophs were analyzed by PCR amplification of 16S rRNA (Ettwig et al. 2009) and pmoA (Luesken et al. 2011) genes followed by construction of clone libraries. Phylogenetic analysis revealed only one n-damo bacterium distantly related to uncultured anaerobic methanotrophs found in situ. It may represent a new cluster of NC10 bacteria with an identity of less than 96 and 86% to the 16S rRNA and pmoA genes of "Ca. Methylomirabilis oxyfera," respectively. An enrichment of nitrite-reducing methanotrophic NC10 bacteria was successfully obtained from this sample in a static anaerobic culture with methane and nitrite at an in situ pH of 6.3. The bacterial abundance in enrichment was estimated using quantitative PCR and FISH (DBACT-0193-a-A probe) analysis and was found to increase up to 10 times for 120 days. The results of this study expand our knowledge of the diversity and distribution of NC10 bacteria in the environment and their potential contribution to nitrogen and methane cycles in northern peatland ecosystems. We think that AOM may be more active in anthropogenic disturbed peatlands with greater supply of elements that could potentially serve as electron acceptors. In spite of generally low concentration, seasonal increases in nitrate content in drained peatlands may work as an important control of CH4 fluxes. The study was partially supported by RFBR research project # 12-05-01029_a.

Fourier domain low coherence interferometry for detection of early colorectal cancer development in the AOM rat model

NASA Astrophysics Data System (ADS)

Robles, Francisco E.; Zhu, Yizheng; Lee, Jin; Sharma, Sheela; Wax, Adam

2011-03-01

We present Fourier domain low coherence interferometry (fLCI) applied to the detection of preneoplastic changes in the colon using the ex-vivo azoxymethane (AOM) rat carcinogenesis model. fLCI measures depth resolved spectral oscillations, also known as local oscillations, resulting from coherent fields induced by the scattering of cell nuclei. The depth resolution of fLCI permits nuclear morphology measurements within thick tissues, making the technique sensitive to the earliest stages of precancerous development. To achieve depth resolved spectroscopic analysis, we use the dual window method, which obtains simultaneously high spectral and depth resolution and yields access to the local oscillations. The results show highly statistically significant differences between the AOM-treated and control group samples. Further, the results suggest that fLCI may be used to detect the field effect of carcinogenesis, in addition to identifying specific areas where more advanced neoplastic development has occurred.

Ventilation tube treatment: a systematic review of the literature.

PubMed

Hellström, Sten; Groth, Anita; Jörgensen, Finn; Pettersson, Agneta; Ryding, Marie; Uhlén, Inger; Boström, Kristina Bengtsson

2011-09-01

The aim of this review was to study the effectiveness of ventilation tube (VT) treatment in children with secretory otitis media (SOM), assessed by improved hearing, normalized language and quality of life (QoL), and recurrent acute otitis media (rAOM), assessed by number of episodes of AOM and QoL. Data Sources. Cochrane Library, PubMed, and Embase databases were searched for randomized and nonrandomized controlled trials and cohort studies in English, Scandinavian, German, and French languages between 1966 and April 2007. Additional literature was retrieved from reference lists in the articles. A total of 493 abstracts were evaluated independently by 2 members of the project group, 247 full-text versions were assessed for inclusion criteria and quality using structured evaluation forms, and 63 articles were included in the review. This review shows that there is strong scientific evidence (grade 1) that VT treatment of SOM improves hearing for at least 9 months and that QoL is improved for up to 9 months (grade 2 scientific evidence). There was insufficient evidence to support an effect of VT treatment for rAOM. There was also insufficient evidence to determine whether the design or material of the VT or the procedure used for insertion had any influence on the effect; however, there was some evidence (grade 3) that aspiration of secretion at insertion does not prolong VT treatment. Further research is needed to address these issues.

Differences in innate immune response gene regulation in the middle ear of children who are otitis prone and in those not otitis prone

PubMed Central

Casey, Janet; Pichichero, Michael

2016-01-01

Objective: Acute otitis media (AOM) causes an inflammatory response in the middle ear. We assessed differences in innate immune responses involved in bacterial defense at onset of AOM in children who were stringently defined as otitis prone (sOP) and children not otitis prone (NOP). Study Design: Innate immune genes analysis from middle ear fluid (MEF) samples of children. Methods: Genes of toll-like receptors (TLR), nod-like and retinoic acid-inducible gene-I-like receptors, downstream effectors important for inflammation and apoptosis, including cytokines and chemokines, were studied from MEF samples by using a real-time polymerase chain reaction array. Protein levels of differentially regulated genes were measured by Luminex. Results: Gene expression in MEF among children who were sOP was significantly different in upregulation of interleukin 8, secretory leukocyte peptidase inhibitor, and chemokine (C-C motif) ligand 3, and in downregulation of interferon regulatory factor 7 and its related signaling molecules interferon alpha, Toll-like receptor adaptor molecule 2, chemokine (C-C motif) ligand 5, and mitogen-activated protein kinase 8 compared with children who were NOP. Differences in innate gene regulation were similar when AOM was caused by Streptococcus pneumoniae or nontypeable Haemophilus influenzae. Conclusion: Innate-immune response genes are differentially regulated in children who were sOP compared with children with NOP. PMID:28124644

Senna and the formation of aberrant crypt foci and tumors in rats treated with azoxymethane.

PubMed

Borrelli, F; Capasso, R; Aviello, G; Di Carlo, G; Izzo, A A; Mascolo, N; Capasso, F

2005-06-01

Chronic use of anthraquinone laxatives has been blamed for the induction of habituation and the development of colonic cancer, but there are no definitive studies which have demonstrated this. To evaluate the carcinogenic potential of anthraquinones, the effect of long-term senna pod extract (SE) treatment on either healthy rats or rats treated with an initiating tumor agent (azoxymethane--AOM) has been studied. SE (30 and 60mg/kg), administered for 110 weeks, did not induce the development of aberrant crypt foci (ACF) and tumors in healthy rats. The development of ACF and tumors in rats treated with AOM were significantly reduced by SE (30 and 60 mg/kg). These results suggest that a chronic SE use does not predispose to colon cancer. By contrast, SE might exert an anti-tumoral activity on rat colon carcinogenesis.

Smad2/3 linker phosphorylation is a possible marker of cancer stem cells and correlates with carcinogenesis in a mouse model of colitis-associated colorectal cancer.

PubMed

Suzuki, Ryo; Fukui, Toshiro; Kishimoto, Masanobu; Miyamoto, Sachi; Takahashi, Yu; Takeo, Masahiro; Mitsuyama, Toshiyuki; Sakaguchi, Yutaku; Uchida, Kazushige; Nishio, Akiyoshi; Okazaki, Kazuichi

2015-07-01

Epithelial cells affected by somatic mutations undergo transition from a tumour-suppressive to a carcinogenic Smad pathway during sporadic colorectal carcinogenesis, and the specific linker threonine phosphorylation of Smad2/3 in colon epithelial cells indicates stem-like cells. This study extends previous observations to a model of colitis-associated colorectal cancer. After Crl:CD-1 mice received an administration of azoxymethane [AOM], the mice were given dextran sodium sulfate [DSS] for 7 days. AOM/DSS-treated mice [AOM/DSS mice] were killed at 10 or 20 weeks. After macroscopic observations, a histopathological analysis was conducted. Immunohistochemical staining was performed using the avidin-biotin immunoperoxidase method [pSmad3C-Ser, pSmad3L-Ser, c-Myc] and immunofluorescent methods [Ki67, β-catenin, CDK4, cyclin D1, Sox9, pSmad2/3L-Thr]. The colons from AOM/DSS mice were shorter than those from control mice. The number of colon tumours at Week 20 was higher than at Week 10. The inflammation scores for AOM/DSS mice were greater than those for control mice. Immunostaining-positive cells (staining by Ki67, β-catenin [nuclear and cytoplasmic], cyclin D1, and Sox9) were diffusely distributed in colon tumours. The percentage of pSmad3L-Ser-positive cells in colon tumours was higher than in sites of pre-neoplastic colitis, and that in sites of pre-neoplastic colitis was higher than in control mice. pSmad2/3L-Thr-positive cells were sparsely detected around crypt bases in non-neoplastic colon epithelia and at the tops of tumours, and immunohistochemical co-localisation of pSmad2/3L-Thr with Ki67 was not observed. Immunohistochemical co-localisation of pSmad2/3L-Thr with β-catenin and CDK4 was observed. pSmad3L-Ser signalling is an early event in colitis-associated colorectal cancer, and pSmad2/3L-Thr immunostaining-positive cells might be cancer stem cells. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Iron-Coupled Anaerobic Oxidation of Methane Performed by a Mixed Bacterial-Archaeal Community Based on Poorly Reactive Minerals.

PubMed

Bar-Or, Itay; Elvert, Marcus; Eckert, Werner; Kushmaro, Ariel; Vigderovich, Hanni; Zhu, Qingzeng; Ben-Dov, Eitan; Sivan, Orit

2017-11-07

Anaerobic oxidation of methane (AOM) was shown to reduce methane emissions by over 50% in freshwater systems, its main natural contributor to the atmosphere. In these environments iron oxides can become main agents for AOM, but the underlying mechanism for this process has remained enigmatic. By conducting anoxic slurry incubations with lake sediments amended with 13 C-labeled methane and naturally abundant iron oxides the process was evidenced by significant 13 C-enrichment of the dissolved inorganic carbon pool and most pronounced when poorly reactive iron minerals such as magnetite and hematite were applied. Methane incorporation into biomass was apparent by strong uptake of 13 C into fatty acids indicative of methanotrophic bacteria, associated with increasing copy numbers of the functional methane monooxygenase pmoA gene. Archaea were not directly involved in full methane oxidation, but their crucial participation, likely being mediators in electron transfer, was indicated by specific inhibition of their activity that fully stopped iron-coupled AOM. By contrast, inhibition of sulfur cycling increased 13 C-methane turnover, pointing to sulfur species involvement in a competing process. Our findings suggest that the mechanism of iron-coupled AOM is accomplished by a complex microbe-mineral reaction network, being likely representative of many similar but hidden interactions sustaining life under highly reducing low energy conditions.

Impact of pneumococcal conjugate vaccine in children morbidity and mortality in Peru: Time series analyses.

PubMed

Suarez, Victor; Michel, Fabiana; Toscano, Cristiana M; Bierrenbach, Ana Luiza; Gonzales, Marco; Alencar, Airlane Pereira; Ruiz Matus, Cuauhtemoc; Andrus, Jon K; de Oliveira, Lucia H

2016-09-07

Streptococcus pneumoniae is the leading cause of bacterial pneumonia, meningitis and sepsis in children worldwide. Despite available evidence on pneumococcal conjugate vaccine (PCV) impact on pneumonia hospitalizations in children, studies demonstrating PCV impact in morbidity and mortality in middle-income countries are still scarce. Given the disease burden, PCV7 was introduced in Peru in 2009, and then switched to PCV10 in late 2011. National public healthcare system provides care for 60% of the population, and national hospitalization, outpatient and mortality data are available. We thus aimed to assess the effects of routine PCV vaccination on pneumonia hospitalization and mortality, and acute otitis media (AOM) and all cause pneumonia outpatient visits in children under one year of age in Peru. We conducted a segmented time-series analysis using outcome-specific regression models. Study period was from January 2006 to December 2012. Data sources included the National information systems for hospitalization, mortality, outpatient visits, and RENACE, the national database of aggregated weekly notifications of pneumonia and other acute respiratory diseases (both hospitalized and non-hospitalized). Study outcomes included community acquired pneumonia outpatient visits, hospitalizations and deaths (ICD10 codes J12-J18); and AOM outpatient visits (H65-H67). Monthly age- and sex-specific admission, outpatient visit, and mortality rates per 100,000 children aged <1year, as well as weekly rates for pneumonia and AOM recorded in RENACE were estimated. After PCV introduction, we observed significant vaccine impact in morbidity and mortality in children aged <1year. Vaccine effectiveness was 26.2% (95% CI 16.9-34.4) for AOM visits, 35% (95% CI 8.6-53.8) for mortality due to pneumonia, and 20.6% (95% CI 10.6-29.5) for weekly cases of pneumonia hospitalization and outpatient visits notified to RENACE. We used secondary data sources which are usually developed for other non-epidemiologic purposes. Despite some data limitations, our results clearly demonstrate the overall benefit of PCV vaccination in Peru. Copyright © 2016. Published by Elsevier Ltd.

Influence of AOM on iron-sulfur-carbon systematics in marine sediment: A study from Krishna-Godavari basin, Bay of Bengal

NASA Astrophysics Data System (ADS)

Carvalho, M. A.

2017-12-01

Sedimentary diagenetic processes play key role in global sulfur-iron-carbon cycle. Microbially driven organoclastic sulfate reduction and anaerobic oxidation of methane (AOM) pathways are responsible for sulfate reduction in marine sediments. Concomitant H2S production and iron sulfide precipitation lead to Fe-sulfide burial in the sediments. Intra/intermolecular organic bound sulfur is also another major sink of global sulfur burial. In the present study, we have investigated the sulfidisation process in a core from Krishna-Godavari (K-G) basin, Bay of Bengal. K-G basin is well known for gas hydrate deposits and methane enrichment within 100-120 mbsf. Previous work from K-G basin has shown tell-tale evidence of paleo episodic- methane expulsion events and formation of authigenic carbonate crust at or above the sea floor1. Our study was carried out on a core MD-161-15 (water depth of 983 m and Lat. =16° 00.5700' N;Long. = 82° 03.4502' E) recovered on board R/V Marion Dufrense). The pyrite content in the core (measured as chromium reducible sulfur: CRS) range from 0.003 to 1.1 wt%. The reactive content (FeTR = FeOx + FeD + FeCRS) range from 0.9 to 3.5 wt%, where FeOX, FeD and FeCRS represents oxalate extractable (magnetite), buffered dithionite extractable (ferrihydrite, lepidocrocite, goethite, hematite) and boiling CrCl2 (in 6N HCl) extractable (Pyrite: FeS2) iron respectively. The δ34SCRS range from -49 to +16.7 ‰ VCDT and show good positive correlation with FeTR. Presence of highly 13C depleted authigenic carbonate in the sediments within 1600-3000 mbsf indicate influence of AOM and possible methane seepage2. The δ34SCRS profile show marked 34S depletion trend within the top 1012 mbsf. Below this depth, δ34SCRS values show steadily increasing trend superimposed by zones of sharp enrichment/ depletion of 34S. The 34S enrichment trend may attributed to late diagenetic pyritization from 34S enriched H2S produced from residual pore water sulfate via AOM pathway.

Chemoprevention of colorectal cancer by black raspberry anthocyanins involved the modulation of gut microbiota and SFRP2 demethylation.

PubMed

Chen, Lili; Jiang, Bowen; Zhong, Chunge; Guo, Jun; Zhang, Lihao; Mu, Teng; Zhang, Qiuhua; Bi, Xiuli

2018-03-08

Freeze-dried black raspberry (BRB) powder is considered as a potential cancer chemopreventive agent. In this study, we fed azoxymethane (AOM)/dextran sodium sulfate (DSS)-treated C57BL/6J mice with a diet containing BRB anthocyanins for 12 weeks, and this led to a reduction in colon carcinogenesis. These animals had consistently lower tumor multiplicity compared with AOM/DSS-treated mice not receiving BRB anthocyanins. In AOM/DSS-treated mice, the number of pathogenic bacteria, including Desulfovibrio sp. and Enterococcus spp., was increased significantly, whereas probiotics such as Eubacterium rectale, Faecalibacterium prausnitzii and Lactobacillus were dramatically decreased, but BRB anthocyanins supplement could reverse this imbalance in gut microbiota. BRB anthocyanins also caused the demethylation of the SFRP2 gene promoter, resulting in increased expression of SFRP2, both at the mRNA and protein levels. Furthermore, the expression levels of DNMT31 and DNMT3B, as well as of p-STAT3 were downregulated by BRB anthocyanins in these animals. Taken together, these results suggested that BRB anthocyanins could modulate the composition of gut commensal microbiota, and changes in inflammation and the methylation status of the SFRP2 gene may play a central role in the chemoprevention of CRC.

Dinitrogen and Cyanide Fixation by Methane Seep Microorganisms Revealed by FISH- SIMS And Implications for AOM Productivity and Nitrogenase Evolution

NASA Astrophysics Data System (ADS)

Dekas, A.; Orphan, V.

2008-12-01

The anaerobic oxidation of methane (AOM), mediated by methane oxidizing archaea (ANME) and sulfate reducing bacterial symbionts (SRB), minimizes the flux of methane from marine sediment to the overlying water column. Understanding the factors determining AOM productivity, and particularly the rates of methane catabolism and anabolism, is of interest to both modern and ancient investigations of climate and bulk carbon isotopic change. It has been hypothesized that nitrogen availability in methane seeps is temporally variable, and that the seep biomass may be at least partially nitrogen limited. The recent finding of nif genes, those necessary for the production of nitrogenase, in enrichments of ANME and SRB consortia suggested that the organisms mediating AOM have the potential to fix dinitrogen. In the present study we incubated methane seep sediment with nitrogen-deplete artificial marine media and a headspace of methane (CH4) and either 15N-labeled dinitrogen (15N2), cyanide (C15N-), or ammonia (15NH3) in order to (1) test the ability of these currently unculturable microorganisms to fix nitrogen and other triple bonded substrates, (2) investigate which AOM partner was responsible for the fixation, (3) compare growth rates on different nitrogen sources, and (4) characterize the phylogeny of these methane seep-associated nitrogenases. Fluorescence in situ hybridization coupled to nano-scale Secondary Ion Mass Spectroscopy imaging (FISH-SIMS) revealed incorporation of 15N into ANME and SRB biomass of up to 0.06 15N fractional abundance in the 15N2 incubation, and up to 0.02 in the C15N- incubation, after 6 and 4 months, respectively. This represents a nearly ten-fold enrichment of 15N compared to the measured natural 15N fractional abundance (0.0036). The NanoSIMS ion images of ANME/SRB aggregates from 15N2 incubations show evidence for 15N enrichment in both partners with the highest incorporation of 15N within the methanotrophic ANME cells. Cyanide incubations revealed a more heterogeneous pattern of 15N distribution, with localized zones of enrichment within both the SRB and the ANME biomass. From these findings, two alternative explanations are considered: (1) both partners are capable of nitrogenase production, but express the nif genes under different conditions, and (2) the distribution of fixed nitrogen within the ANME and SRB is driven by intimate metabolic coupling and resource sharing, with only one partner serving as the primary diazotroph. In incubations with 15NH3, the AOM biomass 15N fractional abundance was nearly 1.0 after 6 months, demonstrating a much faster growth rate when NH3 rather than N2 or CN- is the nitrogen source, consistent with what is observed in other diazotrophic organisms. Nitrogenase genes recovered from these incubations primarily were associated with the nifH group III clade, but the majority were diverged from known nifH sequences. This suggests that novel nitrogenases are responsible for the N2 fixation observed, and the poor substrate specificity and the potential use as a CN- detoxification mechanism could imply that they are similar to the first nitrogenases. The finding that nitrogen fixation occurs within these potentially ancient organisms therefore may provide a window for examining the history and functional diversity of nitrogenase, and the variable growth rates depending on nitrogen substrate could have implications for AOM productivity through time.

The impact of different strategies to handle missing data on both precision and bias in a drug safety study: a multidatabase multinational population-based cohort study

PubMed Central

Martín-Merino, Elisa; Calderón-Larrañaga, Amaia; Hawley, Samuel; Poblador-Plou, Beatriz; Llorente-García, Ana; Petersen, Irene; Prieto-Alhambra, Daniel

2018-01-01

Background Missing data are often an issue in electronic medical records (EMRs) research. However, there are many ways that people deal with missing data in drug safety studies. Aim To compare the risk estimates resulting from different strategies for the handling of missing data in the study of venous thromboembolism (VTE) risk associated with antiosteoporotic medications (AOM). Methods New users of AOM (alendronic acid, other bisphosphonates, strontium ranelate, selective estrogen receptor modulators, teriparatide, or denosumab) aged ≥50 years during 1998–2014 were identified in two Spanish (the Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria [BIFAP] and EpiChron cohort) and one UK (Clinical Practice Research Datalink [CPRD]) EMR. Hazard ratios (HRs) according to AOM (with alendronic acid as reference) were calculated adjusting for VTE risk factors, body mass index (that was missing in 61% of patients included in the three databases), and smoking (that was missing in 23% of patients) in the year of AOM therapy initiation. HRs and standard errors obtained using cross-sectional multiple imputation (MI) (reference method) were compared to complete case (CC) analysis – using only patients with complete data – and longitudinal MI – adding to the cross-sectional MI model the body mass index/smoking values as recorded in the year before and after therapy initiation. Results Overall, 422/95,057 (0.4%), 19/12,688 (0.1%), and 2,051/161,202 (1.3%) VTE cases/participants were seen in BIFAP, EpiChron, and CPRD, respectively. HRs moved from 100.00% underestimation to 40.31% overestimation in CC compared with cross-sectional MI, while longitudinal MI methods provided similar risk estimates compared with cross-sectional MI. Precision for HR improved in cross-sectional MI versus CC by up to 160.28%, while longitudinal MI improved precision (compared with cross-sectional) only minimally (up to 0.80%). Conclusion CC may substantially affect relative risk estimation in EMR-based drug safety studies, since missing data are not often completely at random. Little improvement was seen in these data in terms of power with the inclusion of longitudinal MI compared with cross-sectional MI. The strategy for handling missing data in drug safety studies can have a large impact on both risk estimates and precision.

The impact of different strategies to handle missing data on both precision and bias in a drug safety study: a multidatabase multinational population-based cohort study.

PubMed

Martín-Merino, Elisa; Calderón-Larrañaga, Amaia; Hawley, Samuel; Poblador-Plou, Beatriz; Llorente-García, Ana; Petersen, Irene; Prieto-Alhambra, Daniel

2018-01-01

Missing data are often an issue in electronic medical records (EMRs) research. However, there are many ways that people deal with missing data in drug safety studies. To compare the risk estimates resulting from different strategies for the handling of missing data in the study of venous thromboembolism (VTE) risk associated with antiosteoporotic medications (AOM). New users of AOM (alendronic acid, other bisphosphonates, strontium ranelate, selective estrogen receptor modulators, teriparatide, or denosumab) aged ≥50 years during 1998-2014 were identified in two Spanish (the Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria [BIFAP] and EpiChron cohort) and one UK (Clinical Practice Research Datalink [CPRD]) EMR. Hazard ratios (HRs) according to AOM (with alendronic acid as reference) were calculated adjusting for VTE risk factors, body mass index (that was missing in 61% of patients included in the three databases), and smoking (that was missing in 23% of patients) in the year of AOM therapy initiation. HRs and standard errors obtained using cross-sectional multiple imputation (MI) (reference method) were compared to complete case (CC) analysis - using only patients with complete data - and longitudinal MI - adding to the cross-sectional MI model the body mass index/smoking values as recorded in the year before and after therapy initiation. Overall, 422/95,057 (0.4%), 19/12,688 (0.1%), and 2,051/161,202 (1.3%) VTE cases/participants were seen in BIFAP, EpiChron, and CPRD, respectively. HRs moved from 100.00% underestimation to 40.31% overestimation in CC compared with cross-sectional MI, while longitudinal MI methods provided similar risk estimates compared with cross-sectional MI. Precision for HR improved in cross-sectional MI versus CC by up to 160.28%, while longitudinal MI improved precision (compared with cross-sectional) only minimally (up to 0.80%). CC may substantially affect relative risk estimation in EMR-based drug safety studies, since missing data are not often completely at random. Little improvement was seen in these data in terms of power with the inclusion of longitudinal MI compared with cross-sectional MI. The strategy for handling missing data in drug safety studies can have a large impact on both risk estimates and precision.

Danish guidelines on management of otitis media in preschool children.

PubMed

Heidemann, C H; Lous, J; Berg, J; Christensen, J J; Håkonsen, S J; Jakobsen, M; Johansen, C J; Nielsen, L H; Hansen, M P; Poulsen, A; Schousboe, L P; Skrubbeltrang, C; Vind, A B; Homøe, P

2016-08-01

Otitis media is one of the most common diseases in small children. This underlines the importance of optimizing diagnostics and treatment of the condition. Recent literature points toward a stricter approach to diagnosing acute otitis media (AOM). Moreover, ventilating tube treatment for recurrent AOM (RAOM) and chronic otitis media with effusion (COME) has become the most frequently performed surgical procedure in pre-school children. Therefore, the Danish Health and Medicines Authority and the Danish Society of Otorhinolaryngology, Head and Neck Surgery deemed it necessary to update the Danish guidelines regarding the diagnostic criteria for acute otitis media and surgical treatment of RAOM and COME. The GRADE system (The Grading of Recommendations Assessment, Development and Evaluation) was used in order to comply with current standards of evidence assessment in formulation of recommendations. An extensive literature search was conducted between July and December 2014. The quality of the existing literature was assessed using AGREE II (Appraisal of Guidelines for Research & Evaluation), AMSTAR (assessing the Methodological Quality of Systematic Reviews), QUADAS-2 (Quality of Diagnostic Accuracy Studies), Cochrane Risk of Bias Tool for randomized trials and ACROBAT-NRSI (A Cochrane Risk of Bias Assessment Tool for Non-Randomized Studies). The working group consisted of otolaryngologists, general practitioners, pediatricians, microbiologists and epidemiologists. Recommendations for AOM diagnosis, surgical management for RAOM and COME, including the role of adenoidectomy and treatment of ventilating tube otorrhea, are proposed in the guideline. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Physicochemical and nutraceutical properties of moringa (Moringa oleifera) leaves and their effects in an in vivo AOM/DSS-induced colorectal carcinogenesis model.

PubMed

Cuellar-Nuñez, M L; Luzardo-Ocampo, I; Campos-Vega, R; Gallegos-Corona, M A; González de Mejía, E; Loarca-Piña, G

2018-03-01

Moringa (Moringa oleifera) is a plant that has generated great interest in recent years because of its attributed medicinal properties. The aim of this study was to characterize the bioactive compounds of moringa leaves (MO) and evaluate their effect on a colorectal carcinogenesis model. Twenty-four male CD-1 mice were divided into 4 groups: Group 1 fed with basal diet (negative control/NC); Group 2 received AOM/DSS (positive control); Groups 3 and 4 were fed with basal diet supplemented with moringa leaves (2.5% w/w and 5% w/w, respectively) for 12weeks. Moringa leaves exhibited a high content of dietary fiber (~18.75%) and insoluble dietary fiber (2.29%). There were identified 9 phenolic compounds whereas the chlorogenic and ρ-coumaric acid showed the higher contents (44.23-63.34μg/g and 180.45-707.42μg/g, respectively). Moringa leaves decreased the activity of harmful fecal enzymes (β-glucosidase, β-glucuronidase, tryptophanase and urease up to 40%, 43%, 103% and 266%, respectively) as well tumors incidence in male CD1-mice (~50% with 5% w/v of moringa dose). These findings suggest that the bioactive compounds of moringa such as total dietary fiber and phenolic compounds may have chemopreventive capacity. This is the first study of the suppressive effect of moringa leaves in an in vivo model of AOM/DSS-induced colorectal carcinogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Should homeopathy be considered as part of a treatment strategy for otitis media with effusion in children?

PubMed

Fixsen, Alison

2013-04-01

Otitis media with effusion (OME) or 'glue ear' is the most common cause of pediatric hearing loss, and a drain on global healthcare resources. It is associated with frequent episodes of acute otitis media (AOM) and upper respiratory tract infections (URTIs) and linked with environmental and social factors, including diet, smoking households, overcrowding and day care use. Current conventional treatment for OME is unsatisfactory, the area constitutes an 'effectiveness gap'. Homeopathy is a relatively common and popular choice of complementary and alternative medicine (CAM) treatment for childhood conditions, including otitis media. Antibiotic resistance is now a major global problem, homeopathy may have a role to play in combating its further development. Systematic review of the literature for clinical studies of homeopathy for AOM and upper respiratory tract disorders. Discussion in the context of current treatment options and public health issues including antibiotic resistance. Several randomized trials and outcome studies of homeopathy for AOM and upper respiratory tract disorders have been published. The results are encouraging, but the volume of research is small and insufficient to draw definitive conclusions. A strategy based on multi-centre or multiple, linked clinical trials of homeopathy for OME, using a pragmatic framework and evaluating long-term effects in different settings, in conjunction with other healthcare and social services should be considered. Reduction of antibiotic use is an important outcome. Copyright © 2013 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

Microbial Community Composition and Functional Capacity in a Terrestrial Ferruginous, Sulfate-Depleted Mud Volcano

PubMed Central

Tu, Tzu-Hsuan; Wu, Li-Wei; Lin, Yu-Shih; Imachi, Hiroyuki; Lin, Li-Hung; Wang, Pei-Ling

2017-01-01

Terrestrial mud volcanoes (MVs) are an important natural source of methane emission. The role of microbial processes in methane cycling and organic transformation in such environments remains largely unexplored. In this study, we aim to uncover functional potentials and community assemblages across geochemical transitions in a ferruginous, sulfate-depleted MV of eastern Taiwan. Geochemical profiles combined with 16S rRNA gene abundances indicated that anaerobic oxidation of methane (AOM) mediated by ANME-2a group coincided with iron/manganese reduction by Desulfuromonadales at shallow depths deprived of sulfate. The activity of AOM was stimulated either by methane alone or by methane and a range of electron acceptors, such as sulfate, ferrihydrite, and artificial humic acid. Metagenomic analyses revealed that functional genes for AOM and metal reduction were more abundant at shallow intervals. In particular, genes encoding pili expression and electron transport through multi-heme cytochromes were prevalent, suggesting potential intercellular interactions for electron transport involved in AOM. For comparison, genes responsible for methanogenesis and degradation of chitin and plant-derived molecules were more abundant at depth. The gene distribution combined with the enhanced proportions of 16S rRNA genes related to methanogens and heterotrophs, and geochemical characteristics suggest that particulate organic matter was degraded into various organic entities that could further fuel in situ methanogenesis. Finally, genes responsible for aerobic methane oxidation were more abundant in the bubbling pool and near-surface sediments. These methane oxidizers account for the ultimate attenuation of methane discharge into the atmosphere. Overall, our results demonstrated that various community members were compartmentalized into stratified niches along geochemical gradients. These community members form a metabolic network that cascades the carbon transformation from the upstream degradation of recalcitrant organic carbon with fermentative production of labile organic entities and methane to downstream methane oxidation and metal reduction near the surface. Such a metabolic architecture enables effective methane removal under ferruginous, sulfate-depleted conditions in terrestrial MVs. PMID:29163423

Microbial Community Composition and Functional Capacity in a Terrestrial Ferruginous, Sulfate-Depleted Mud Volcano.

PubMed

Tu, Tzu-Hsuan; Wu, Li-Wei; Lin, Yu-Shih; Imachi, Hiroyuki; Lin, Li-Hung; Wang, Pei-Ling

2017-01-01

Terrestrial mud volcanoes (MVs) are an important natural source of methane emission. The role of microbial processes in methane cycling and organic transformation in such environments remains largely unexplored. In this study, we aim to uncover functional potentials and community assemblages across geochemical transitions in a ferruginous, sulfate-depleted MV of eastern Taiwan. Geochemical profiles combined with 16S rRNA gene abundances indicated that anaerobic oxidation of methane (AOM) mediated by ANME-2a group coincided with iron/manganese reduction by Desulfuromonadales at shallow depths deprived of sulfate. The activity of AOM was stimulated either by methane alone or by methane and a range of electron acceptors, such as sulfate, ferrihydrite, and artificial humic acid. Metagenomic analyses revealed that functional genes for AOM and metal reduction were more abundant at shallow intervals. In particular, genes encoding pili expression and electron transport through multi-heme cytochromes were prevalent, suggesting potential intercellular interactions for electron transport involved in AOM. For comparison, genes responsible for methanogenesis and degradation of chitin and plant-derived molecules were more abundant at depth. The gene distribution combined with the enhanced proportions of 16S rRNA genes related to methanogens and heterotrophs, and geochemical characteristics suggest that particulate organic matter was degraded into various organic entities that could further fuel in situ methanogenesis. Finally, genes responsible for aerobic methane oxidation were more abundant in the bubbling pool and near-surface sediments. These methane oxidizers account for the ultimate attenuation of methane discharge into the atmosphere. Overall, our results demonstrated that various community members were compartmentalized into stratified niches along geochemical gradients. These community members form a metabolic network that cascades the carbon transformation from the upstream degradation of recalcitrant organic carbon with fermentative production of labile organic entities and methane to downstream methane oxidation and metal reduction near the surface. Such a metabolic architecture enables effective methane removal under ferruginous, sulfate-depleted conditions in terrestrial MVs.

Dietary butyrylated high-amylose starch reduces azoxymethane-induced colonic O(6)-methylguanine adducts in rats as measured by immunohistochemistry and high-pressure liquid chromatography.

PubMed

Le Leu, Richard K; Scherer, Benjamin L; Mano, Mark T; Winter, Jean M; Lannagan, Tamsin; Head, Richard J; Lockett, Trevor; Clarke, Julie M

2016-09-01

O(6)-methyl guanine (O(6)MeG) adducts are major toxic, promutagenic, and procarcinogenic adducts involved in colorectal carcinogenesis. Resistant starch and its colonic metabolite butyrate are known to protect against oncogenesis in the colon. In this study, we hypothesized that a dietary intervention that specifically delivers butyrate to the large bowel (notably butyrylated high-amylose maize starch [HAMSB]) would reduce colonic levels of O(6)MeG in rats shortly after exposure to the deoxyribonucleic acid (DNA) alkylating agent azoxymethane (AOM) when compared with a low-amylose maize starch (LAMS). A further objective was to validate an immunohistochemistry (IHC) method for quantifying O(6)MeG against a high-performance liquid chromatography method using fluorescence and diode array detection. Rats were fed either LAMS or HAMSB diets for 4 weeks followed by a single injection of AOM or saline and killed 6 hours later. After AOM exposure, both IHC and high-performance liquid chromatography method using fluorescence and diode array detection measured a substantially increased quantity of DNA adducts in the colon (P<.001). Both techniques demonstrated equally that consumption of HAMSB provided a protective effect by reducing colonic adduct load compared with the LAMS diet (P<.05). In addition, IHC allowed visualization of the O(6)MeG distribution, where adduct load was reduced in the lower third of the crypt compartment in HAMSB-fed rats (P=.036). The apoptotic response to AOM was higher in the HAMSB-fed rats (P=.002). In conclusion, the reduction in O(6)MeG levels and enhancement of the apoptotic response to DNA damage in the colonic epithelium through consumption of HAMSB provide mechanistic insights into how HAMSB protects against colorectal tumorigenesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Blueberry consumption inhibits gastrointestinal tumorigenesis in AOM-treated rats

USDA-ARS?s Scientific Manuscript database

Epidemiological studies show inverse or no association of fruit consumption with relative risk for colorectal cancers. Such studies did not examine specific fruits and in particular, those enriched in polyphenols with high antioxidant capacities. We examined blueberry (BB), a fruit rich in anthocy...

Anaerobic Oxidation of Methane Coupled to Nitrite Reduction by Halophilic Marine NC10 Bacteria.

PubMed

He, Zhanfei; Geng, Sha; Cai, Chaoyang; Liu, Shuai; Liu, Yan; Pan, Yawei; Lou, Liping; Zheng, Ping; Xu, Xinhua; Hu, Baolan

2015-08-15

Anaerobic oxidation of methane (AOM) coupled to nitrite reduction is a novel AOM process that is mediated by denitrifying methanotrophs. To date, enrichments of these denitrifying methanotrophs have been confined to freshwater systems; however, the recent findings of 16S rRNA and pmoA gene sequences in marine sediments suggest a possible occurrence of AOM coupled to nitrite reduction in marine systems. In this research, a marine denitrifying methanotrophic culture was obtained after 20 months of enrichment. Activity testing and quantitative PCR (qPCR) analysis were then conducted and showed that the methane oxidation activity and the number of NC10 bacteria increased correlatively during the enrichment period. 16S rRNA gene sequencing indicated that only bacteria in group A of the NC10 phylum were enriched and responsible for the resulting methane oxidation activity, although a diverse community of NC10 bacteria was harbored in the inoculum. Fluorescence in situ hybridization showed that NC10 bacteria were dominant in the enrichment culture after 20 months. The effect of salinity on the marine denitrifying methanotrophic culture was investigated, and the apparent optimal salinity was 20.5‰, which suggested that halophilic bacterial AOM coupled to nitrite reduction was obtained. Moreover, the apparent substrate affinity coefficients of the halophilic denitrifying methanotrophs were determined to be 9.8 ± 2.2 μM for methane and 8.7 ± 1.5 μM for nitrite. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

E-cadherin Mediates the Preventive Effect of Vitamin D3 in Colitis-associated Carcinogenesis.

PubMed

Xin, Yu; He, Longmei; Luan, Zijian; Lv, Hong; Yang, Hong; Zhou, Ying; Zhao, Xinhua; Zhou, Weixun; Yu, Songlin; Tan, Bei; Wang, Hongying; Qian, Jiaming

2017-09-01

Vitamin D3 is beneficial in ameliorating or preventing inflammation and carcinogenesis. Here, we evaluated if vitamin D3 has a preventive effect on colitis-associated carcinogenesis. Administration of azoxymethane (AOM), followed with dextran sulfate sodium (DSS), was used to simulate colitis-associated colon cancer in mice. The supplement of vitamin D3 at different dosages (15, 30, 60 IU·g·w), started before AOM or immediately after DSS treatment (post 60), was sustained to the end of the experiment. Dietary vitamin D3 significantly reduced the number of tumors and tumor burden in a dose-dependent manner. Of note, vitamin D3 in high doses showed significant preventive effects on carcinogenesis regardless of administration before or after AOM-DSS treatment. Cell proliferation decreased in vitamin D3 groups compared with the control group after inhibition of expression of β-catenin and its downstream target gene cyclin D1 in the colon. In vitro, vitamin D3 reduced the transcriptional activity and nuclear level of β-catenin, and it also increased E-cadherin expression and its binding affinity for β-catenin. Moreover, repression of E-cadherin was rescued by supplemental vitamin D3 in mouse colons. Taken together, our results indicate that vitamin D3 effectively suppressed colonic carcinogenesis in the AOM-DSS mouse model. Our findings further suggest that upregulation of E-cadherin contributes to the preventive effect of vitamin D3 on β-catenin activity.

Fragmentation analysis of water-soluble atmospheric organic matter using ultrahigh-resolution FT-ICR mass spectrometry.

PubMed

Leclair, Jeffrey P; Collett, Jeffrey L; Mazzoleni, Lynn R

2012-04-17

Isolated water-soluble atmospheric organic matter (AOM) analytes extracted from radiation fogwater samples were analyzed using collision induced dissociation with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Tandem mass analysis was performed on several mass ranges between 100 and 400 Da to characterize the functional groups of AOM species. Compounds containing nitrogen and/or sulfur were targeted because of the high number of oxygen atoms contained in their molecular formulas. Due to the large number of isobaric ions in the precursor isolation ranges, large numbers of product ions resulted from collision induced dissociation. Common neutral losses were assigned by matching the molecular formulas of the expected product ions with the detected product ions within the appropriate mass spectra. Since polar functional groups are expected to affect the hygroscopic properties of aerosols, the losses of H(2)O, CO(2), CH(3)OH, HNO(3), CH(3)NO(3), SO(3), SO(4) and combinations of these were specifically targeted. Among the 421 compounds studied, the most frequently observed neutral losses were CO(2) (54%), H(2)O (43%) and CH(3)OH (40%). HNO(3) losses were observed for 63% of the studied nitrogen containing compounds and 33% of the studied compounds containing both nitrogen and sulfur. SO(3) losses were observed for 85% of the studied sulfur containing compounds and 42% of studied compounds containing both nitrogen and sulfur. A number of molecular formulas matching those of monoterpene ozonolysis SOA were observed; they include organonitrates, organosulfates, and nitroxy-organosulfates. Overall, the results of fragmentation analysis of 400+ individual molecular precursors elucidate the complexity and multifunctional nature of the isolated water-soluble AOM.

Naturopathic treatment for ear pain in children.

PubMed

Sarrell, E Michael; Cohen, Herman Avner; Kahan, Ernesto

2003-05-01

Otitis media is 1 of the most frequent diseases of early infancy and childhood and 1 of the most common reasons for children to visit a physician. In the past 2 decades, there has been a substantial increase in the diagnosis of otitis media worldwide. In the United States, 93% of all children have had at least 1 episode of acute otitis media (AOM) by 7 years of age. Otalgia is the hallmark of AOM. Most affected children either complain of earache or manifest behavior that the parents interpret as indicating ear pain. Treatment of the ear pain early in the course of AOM decreases both parental anxiety and the child's discomfort and accelerates the healing process. The objective of this study was to determine the efficacy and tolerability of naturopathic versus traditional treatment for the management of otalgia commonly associated with AOM in children. The study was designed as a double-blind trial in an outpatient community clinic. A total of 171 children who were aged 5 to 18 years and had otalgia and clinical findings associated with middle-ear infection were studied. The children were randomly assigned to receive treatment with Naturopathic Herbal Extract Ear Drops (NHED) or anesthetic ear drops, with or without amoxicillin. On enrollment, the children were assigned by computer-numbered randomization to receive NHED (contents: allium sativum, verbascum thapsus, calendula flores, hypericum perfoliatum, lavender, and vitamin E in olive oil) 5 drops 3 times daily, alone (group A) or together with a topical anesthetic (amethocaine and phenazone in glycerin) 5 drops 3 times daily (group B), or oral amoxicillin 80 mg/kg/d (maximum 500 mg/dose) divided into 3 doses with either NHED 5 drops 3 times daily (group C) or topical anesthetic 5 drops 3 times daily (group D). A double-blind design was used, and all ear drops were placed in identical bottles. Treatment was initiated by the nurse in all cases. A single physician (M.S.) evaluated and treated all of the patients included in the study and recorded all of the data. The presence or absence of ear pain was assessed over 3 days with a visual analog scale. Ear pain was assessed by a specially devised observational instrument based on previous reports. One side of the instrument consisted of a linear numbered scale, from 1 (no pain) to 10 (worst possible pain), and a corresponding color scale, ranging from blue to dark red. The reverse side contained a scale of 5 facial expressions, ranging from broad smile (no pain) to a sad and crying face (worst possible pain), and a corresponding color scale, ranging from blue to dark red. There were no significant between-group differences in patient age or gender, degree of fever, main symptoms, associated symptoms, and severity or laterality of acute otitis media. Each group had a statistically significant improvement in ear pain over the course of the 3 days. Patients who were given ear drops alone had a better response than patients who were given ear drops together with amoxicillin. Results were better in the NHED group than in the controls. Nevertheless, the findings indicated that the pain was mostly (80%) self-limited and could be explained simply by the time elapsed. The American Academy of Otolaryngology-Head and Neck Surgery guidelines recommend topical medications as the first line of treatment for ear pain in the absence of systemic infection or serious underlying disease. Because no evidence was found that systemic antibiotics alone improved treatment outcome, if antibiotics do not change the natural course of otitis media, then the main goal of treatment, as in the present study, should be to alleviate the ear pain. The alternative, naturopathic herbal extract medications, may offer many new possibilities in the management of ear pain associated with AOM. Primary care physicians should be aware that at least 10% of their patients may have tried 1 or more forms of alternative/complementary medicine before presenting for consultation. As it was widely reported in the medical literature, these herb, these herbal extracts have the potential to meet all of the requirements of appropriate medication that could be routinely used in the pediatric patient, namely in vitro bacteriostatic and bacteriocidal activity against common pathogens, immunostimulation ability, antioxidant activity, and anti-inflammatory effects. They are also well-absorbed with good penetration into the tissue surrounding the tympanic membrane. They have been found to enhance local immunologic activity. Finally, herbal extracts are well-tolerated (owing to their long elimination time), easy to administer, and less expensive than the new antibiotics. There are no documented side effects. On the basis of our findings that the group with the most significant treatment effects (NHED with topical anesthetic) explained only 7.3% of the total pain reduction, we propose that sometimes the general practitioner or pediatrician needs to give the human body a chance to repair itself. Nevertheless, if the physician believes that there is an indication for some treatment, especially if the parents are anxious, then a local treatment such as one used in our study might be adequate. This study suggests that in cases of ear pain caused by AOM in children in which active treatment, besides a simple 2- to 3-day waiting period, is needed, an herbal extract solution may be beneficial. Concomitant antibiotic treatment is apparently not contributory.

Optical Carry Adder.

DTIC Science & Technology

1987-03-01

AOM’s) with the deflected beam as the modulator "on" state. These AOM’s ( TeO2 crystals, manufactured by Newport E.O. Systems) have high deflection...caused by the slow acoustic propagation (4.2 - 105 cm/s for TeO2 ), but this delay can be minimized by placing the laser beam close to the acoustic...dependent jitter in the optical carry to below 1 ns, the total carry path must be less than 30 cm long (or 20 cm in glass , 14 cm in LiNbO 3). Thus, a 32

Crisis Management Systems: A Case Study for Aspect-Oriented Modeling

NASA Astrophysics Data System (ADS)

Kienzle, Jörg; Guelfi, Nicolas; Mustafiz, Sadaf

The intent of this document is to define a common case study for the aspect-oriented modeling research community. The domain of the case study is crisis management systems, i.e., systems that help in identifying, assessing, and handling a crisis situation by orchestrating the communication between all parties involved in handling the crisis, by allocating and managing resources, and by providing access to relevant crisis-related information to authorized users. This document contains informal requirements of crisis management systems (CMSs) in general, a feature model for a CMS product line, use case models for a car crash CMS (CCCMS), a domain model for the CCCMS, an informal physical architecture description of the CCCMS, as well as some design models of a possible object-oriented implementation of parts of the CCCMS backend. AOM researchers who want to demonstrate the power of their AOM approach or technique can hence apply the approach at the most appropriate level of abstraction.

Comparison of Mean Climate Trends in the Northern Hemisphere Between N.C.E.P. and Two Atmosphere-Ocean Model Forced Runs

NASA Technical Reports Server (NTRS)

Lucarini, Valerio; Russell, Gary L.; Hansen, James E. (Technical Monitor)

2002-01-01

Results are presented for two greenhouse gas experiments of the Goddard Institute for Space Studies Atmosphere-Ocean Model (AOM). The computed trends of surface pressure, surface temperature, 850, 500 and 200 mb geopotential heights and related temperatures of the model for the time frame 1960-2000 are compared to those obtained from the National Centers for Environmental Prediction observations. A spatial correlation analysis and mean value comparison are performed, showing good agreement. A brief general discussion about the statistics of trend detection is presented. The domain of interest is the Northern Hemisphere (NH) because of the higher reliability of both the model results and the observations. The accuracy that this AOM has in describing the observed regional and NH climate trends makes it reliable in forecasting future climate changes.

Anaerobic oxidation of methane by sulfate in hypersaline groundwater of the Dead Sea aquifer

PubMed Central

Avrahamov, N; Antler, G; Yechieli, Y; Gavrieli, I; Joye, S B; Saxton, M; Turchyn, A V; Sivan, O

2014-01-01

Geochemical and microbial evidence points to anaerobic oxidation of methane (AOM) likely coupled with bacterial sulfate reduction in the hypersaline groundwater of the Dead Sea (DS) alluvial aquifer. Groundwater was sampled from nine boreholes drilled along the Arugot alluvial fan next to the DS. The groundwater samples were highly saline (up to 6300 mm chlorine), anoxic, and contained methane. A mass balance calculation demonstrates that the very low δ13CDIC in this groundwater is due to anaerobic methane oxidation. Sulfate depletion coincident with isotope enrichment of sulfur and oxygen isotopes in the sulfate suggests that sulfate reduction is associated with this AOM. DNA extraction and 16S amplicon sequencing were used to explore the microbial community present and were found to be microbial composition indicative of bacterial sulfate reducers associated with anaerobic methanotrophic archaea (ANME) driving AOM. The net sulfate reduction seems to be primarily controlled by the salinity and the available methane and is substantially lower as salinity increases (2.5 mm sulfate removal at 3000 mm chlorine but only 0.5 mm sulfate removal at 6300 mm chlorine). Low overall sulfur isotope fractionation observed (34ε = 17 ± 3.5‰) hints at high rates of sulfate reduction, as has been previously suggested for sulfate reduction coupled with methane oxidation. The new results demonstrate the presence of sulfate-driven AOM in terrestrial hypersaline systems and expand our understanding of how microbial life is sustained under the challenging conditions of an extremely hypersaline environment. PMID:25039851

Anaerobic oxidation of methane by sulfate in hypersaline groundwater of the Dead Sea aquifer.

PubMed

Avrahamov, N; Antler, G; Yechieli, Y; Gavrieli, I; Joye, S B; Saxton, M; Turchyn, A V; Sivan, O

2014-11-01

Geochemical and microbial evidence points to anaerobic oxidation of methane (AOM) likely coupled with bacterial sulfate reduction in the hypersaline groundwater of the Dead Sea (DS) alluvial aquifer. Groundwater was sampled from nine boreholes drilled along the Arugot alluvial fan next to the DS. The groundwater samples were highly saline (up to 6300 mm chlorine), anoxic, and contained methane. A mass balance calculation demonstrates that the very low δ(13) CDIC in this groundwater is due to anaerobic methane oxidation. Sulfate depletion coincident with isotope enrichment of sulfur and oxygen isotopes in the sulfate suggests that sulfate reduction is associated with this AOM. DNA extraction and 16S amplicon sequencing were used to explore the microbial community present and were found to be microbial composition indicative of bacterial sulfate reducers associated with anaerobic methanotrophic archaea (ANME) driving AOM. The net sulfate reduction seems to be primarily controlled by the salinity and the available methane and is substantially lower as salinity increases (2.5 mm sulfate removal at 3000 mm chlorine but only 0.5 mm sulfate removal at 6300 mm chlorine). Low overall sulfur isotope fractionation observed ((34) ε = 17 ± 3.5‰) hints at high rates of sulfate reduction, as has been previously suggested for sulfate reduction coupled with methane oxidation. The new results demonstrate the presence of sulfate-driven AOM in terrestrial hypersaline systems and expand our understanding of how microbial life is sustained under the challenging conditions of an extremely hypersaline environment. © 2014 The Authors. Geobiology Published by John Wiley & Sons Ltd.

Iron oxides stimulate sulfate-driven anaerobic methane oxidation in seeps

DOE PAGES

Sivan, Orit; Antler, Gilad; Turchyn, Alexandra V.; ...

2014-09-22

Seep sediments are dominated by intensive microbial sulfate reduction coupled to the anaerobic oxidation of methane (AOM). Through geochemical measurements of incubation experiments with methane seep sediments collected from Hydrate Ridge, we provide insight into the role of iron oxides in sulfate-driven AOM. Seep sediments incubated with 13C-labeled methane showed co-occurring sulfate reduction, AOM, and methanogenesis. The isotope fractionation factors for sulfur and oxygen isotopes in sulfate were about 40‰ and 22‰, respectively, reinforcing the difference between microbial sulfate reduction in methane seeps versus other sedimentary environments (for example, sulfur isotope fractionation above 60‰ in sulfate reduction coupled to organicmore » carbon oxidation or in diffusive sedimentary sulfate–methane transition zone). The addition of hematite to these microcosm experiments resulted in significant microbial iron reduction as well as enhancing sulfate-driven AOM. The magnitude of the isotope fractionation of sulfur and oxygen isotopes in sulfate from these incubations was lowered by about 50%, indicating the involvement of iron oxides during sulfate reduction in methane seeps. The similar relative change between the oxygen versus sulfur isotopes of sulfate in all experiments (with and without hematite addition) suggests that oxidized forms of iron, naturally present in the sediment incubations, were involved in sulfate reduction, with hematite addition increasing the sulfate recycling or the activity of sulfur-cycling microorganisms by about 40%. Furthermore, these results highlight a role for natural iron oxides during bacterial sulfate reduction in methane seeps not only as nutrient but also as stimulator of sulfur recycling.« less

Boswellia serrata resin extract alleviates azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon tumorigenesis.

PubMed

Chou, Ya-Chun; Suh, Joon Hyuk; Wang, Yu; Pahwa, Manoj; Badmaev, Vladimir; Ho, Chi-Tang; Pan, Min-Hsiung

2017-09-01

Boswellia serrata (BS) resin is a popular dietary supplement for joint nourishment. In this study, we investigated the chemopreventive effects of dietary BS extract and its impact of gut microbiota on azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-associated colon cancer in mice. Male ICR mice were injected with AOM and 2% DSS via drinking water. The mice were fed with 0.25 or 0.5% BS extract, and colonic tissue were collected at 15 weeks. The main effective components of BS supercritical CO 2 extraction were analyzed by LC-MS/MS are boswellic acids. We found that treatment with BS extract significantly reduce the colonic tumor formation. Western blot and histological analysis revealed that dietary BS extract could markedly reduce the inflammation associated protein levels expression. Furthermore, BS extract reduced cell proliferation via inhibiting phosphorylation level of protein kinase B (Akt), glycogen synthase kinase 3β (GSK3β), and downregulation of cyclin D1. In addition, BS extract also altered the composition of gut microbiota by enhancing the proportion of Clostridiales and reducing the percentage of Bacteroidales. In summary, BS extract decreased the protein levels of inflammative enzymes such as inducible nitric oxide synthase and cyclooxygenase-2 in colonic mucosa. It also mediated Akt/GSK3β/cyclin D1 signaling pathway and altered the composition of gut microbiota to alleviate tumor growth. Taken together, this study suggests that BS extract has great potential to suppress colon tumorigenesis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pathways and regulation of carbon, sulfur and energy transfer in marine sediments overlying methane gas hydrates on the Opouawe Bank (New Zealand)

NASA Astrophysics Data System (ADS)

Dale, A. W.; Sommer, S.; Haeckel, M.; Wallmann, K.; Linke, P.; Wegener, G.; Pfannkuche, O.

2010-10-01

This study combines sediment geochemical analysis, in situ benthic lander deployments and numerical modeling to quantify the biogeochemical cycles of carbon and sulfur and the associated rates of Gibbs energy production at a novel methane seep. The benthic ecosystem is dominated by a dense population of tube-building ampharetid polychaetes and conspicuous microbial mats were unusually absent. A 1D numerical reaction-transport model, which allows for the explicit growth of sulfide and methane oxidizing microorganisms, was tuned to the geochemical data using a fluid advection velocity of 14 cm yr -1. The fluids provide a deep source of dissolved hydrogen sulfide and methane to the sediment with fluxes equal to 4.1 and 18.2 mmol m -2 d -1, respectively. Chemosynthetic biomass production in the subsurface sediment is estimated to be 2.8 mmol m -2 d -1 of C biomass. However, carbon and oxygen budgets indicate that chemosynthetic organisms living directly above or on the surface sediment have the potential to produce 12.3 mmol m -2 d -1 of C biomass. This autochthonous carbon source meets the ampharetid respiratory carbon demand of 23.2 mmol m -2 d -1 to within a factor of 2. By contrast, the contribution of photosynthetically-fixed carbon sources to ampharetid nutrition is minor (3.3 mmol m -2 d -1 of C). The data strongly suggest that mixing of labile autochthonous microbial detritus below the oxic layer sustains high measured rates of sulfate reduction in the uppermost 2 cm of the sulfidic sediment (100-200 nmol cm -3 d -1). Similar rates have been reported in the literature for other seeps, from which we conclude that autochthonous organic matter is an important substrate for sulfate reducing bacteria in these sediment layers. A system-scale energy budget based on the chemosynthetic reaction pathways reveals that up to 8.3 kJ m -2 d -1 or 96 mW m -2 of catabolic (Gibbs) energy is dissipated at the seep through oxidation reactions. The microorganisms mediating sulfide oxidation and anaerobic oxidation of methane (AOM) produce 95% and 2% of this energy flux, respectively. The low power output by AOM is due to strong bioenergetic constraints imposed on the reaction rate by the composition of the chemical environment. These constraints provide a high potential for dissolved methane efflux from the sediment (12.0 mmol m -2 d -1) and indicates a much lower efficiency of (dissolved) methane sequestration by AOM at seeps than considered previously. Nonetheless, AOM is able to consume a third of the ascending methane flux (5.9 mmol m -2 d -1 of CH 4) with a high efficiency of energy expenditure (35 mmol CH 4 kJ -1). It is further proposed that bioenergetic limitation of AOM provides an explanation for the non-zero sulfate concentrations below the AOM zone observed here and in other active and passive margin sediments.

Geochemistry of the alginite and amorphous organic matter from type II-S kerogens

USGS Publications Warehouse

Stankiewicz, B.A.; Kruge, M.A.; Mastalerz, Maria; Salmon, G.L.

1996-01-01

Maceral fractions of the Type II-S kerogens from the Monterey Formation (Miocene. California. U.S.A.) and Duwi Formation (Campanian/Maastrichtian, Egypt) were separated by density gradient centrifugation. The Monterey Fm. kerogen sample was comprised chiefly of light red-fluorescing amorphous organic matter (AOM), the flash pyrolyzate of which was characterized by a predominance of alkylbenzenes, alkylthiophenes and alkylpyrroles. In contrast, the pyrolyzates of its alginite concentrate showed a highly aliphatic character, typical of this maceral, with the series of n-alkenes and n-alkanes (C6- C26) predominating. The pyrolyzate of the dominant light brown-fluorescing AOM of the Duwi Fm. kerogen had a relatively high concentration of alkylbenzenes and alkylthiophenes, while its elginite concentrate showed a more aliphatic character upon pyrolysis. There was a marked enrichment of thiophenic sulfur in the light-colored AOM of both samples (and also pyrrolic nitrogen in the case of the Monterey) relative to the alginite. The results support a bacterially-mediated, degradative origin for Type II-S amorphous organic matter, with algal remains as the primary source of the kerogen.

Microbial community structure in three deep-sea carbonate crusts.

PubMed

Heijs, S K; Aloisi, G; Bouloubassi, I; Pancost, R D; Pierre, C; Sinninghe Damsté, J S; Gottschal, J C; van Elsas, J D; Forney, L J

2006-10-01

Carbonate crusts in marine environments can act as sinks for carbon dioxide. Therefore, understanding carbonate crust formation could be important for understanding global warming. In the present study, the microbial communities of three carbonate crust samples from deep-sea mud volcanoes in the eastern Mediterranean were characterized by sequencing 16S ribosomal RNA (rRNA) genes amplified from DNA directly retrieved from the samples. In combination with the mineralogical composition of the crusts and lipid analyses, sequence data were used to assess the possible role of prokaryotes in crust formation. Collectively, the obtained data showed the presence of highly diverse communities, which were distinct in each of the carbonate crusts studied. Bacterial 16S rRNA gene sequences were found in all crusts and the majority was classified as alpha-, gamma-, and delta- Proteobacteria. Interestingly, sequences of Proteobacteria related to Halomonas and Halovibrio sp., which can play an active role in carbonate mineral formation, were present in all crusts. Archaeal 16S rRNA gene sequences were retrieved from two of the crusts studied. Several of those were closely related to archaeal sequences of organisms that have previously been linked to the anaerobic oxidation of methane (AOM). However, the majority of archaeal sequences were not related to sequences of organisms known to be involved in AOM. In combination with the strongly negative delta 13C values of archaeal lipids, these results open the possibility that organisms with a role in AOM may be more diverse within the Archaea than previously suggested. Different communities found in the crusts could carry out similar processes that might play a role in carbonate crust formation.

Bacterial Species and Antibiotic Sensitivity in Korean Patients Diagnosed with Acute Otitis Media and Otitis Media with Effusion.

PubMed

Kim, Sang Hoon; Jeon, Eun Ju; Hong, Seok Min; Bae, Chang Hoon; Lee, Ho Yun; Park, Moo Kyun; Byun, Jae Yong; Kim, Myung Gu; Yeo, Seung Geun

2017-04-01

Changes over time in pathogens and their antibiotic sensitivity resulting from the recent overuse and misuse of antibiotics in otitis media (OM) have complicated treatment. This study evaluated changes over 5 years in principal pathogens and their antibiotic sensitivity in patients in Korea diagnosed with acute OM (AOM) and OM with effusion (OME). The study population consisted of 683 patients who visited the outpatient department of otorhinolaryngology in 7 tertiary hospitals in Korea between January 2010 and May 2015 and were diagnosed with acute AOM or OME. Aural discharge or middle ear fluid were collected from patients in the operating room or outpatient department and subjected to tests of bacterial identification and antibiotic sensitivity. The overall bacteria detection rate of AOM was 62.3% and OME was 40.9%. The most frequently isolated Gram-positive bacterial species was coagulase negative Staphylococcus aureus (CNS) followed by methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), and Streptococcus pneumonia (SP), whereas the most frequently isolated Gram-negative bacterium was Pseudomonas aeruginosa (PA). Regardless of OM subtype, ≥ 80% of CNS and MRSA strains were resistant to penicillin (PC) and tetracycline (TC); isolated MRSA strains showed low sensitivity to other antibiotics, with 100% resistant to PC, TC, cefoxitin (CFT), and erythromycin (EM); and isolated PA showed low sensitivity to quinolone antibiotics, including ciprofloxacin (CIP) and levofloxacin (LFX), and to aminoglycosides. Bacterial species and antibiotic sensitivity did not change significantly over 5 years. The rate of detection of MRSA was higher in OME than in previous studies. As bacterial predominance and antibiotic sensitivity could change over time, continuous and periodic surveillance is necessary in guiding appropriate antibacterial therapy. © 2017 The Korean Academy of Medical Sciences.

Adenoidectomy with or without grommets for children with otitis media: an individual patient data meta-analysis.

PubMed Central

Boonacker, Chantal W B; Rovers, Maroeska M; Browning, George G; Hoes, Arno W; Schilder, Anne G M; Burton, Martin J

2014-01-01

BACKGROUND Otitis media (OM) is a leading cause of medical consultations, antibiotic prescription and surgery in children. The surgical procedures offered to children with recurrent or persistent OM are insertion of grommets, adenoidectomy or a combination of the two. There is clear National Institute for Health and Care Excellence guidance for the use of grommets in subgroups of children with persistent OM with effusion (OME), but similar guidance is not available for adenoidectomy, either in persistent OME or in recurrent acute OM (AOM). OBJECTIVES (1) To develop a model to predict the risk of children referred for adenoidectomy having a prolonged duration of their OM. Then, (2a) to evaluate the overall effect of adenoidectomy, with or without grommets, on OM using individual patient data (IPD) and (2b) to identify those subgroups of children who are most likely to benefit from adenoidectomy with or without grommets. DATA SOURCES A number of electronic databases were searched from their inception including the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), metaRegister of Current Controlled Trials (mRCT), ClinicalTrials.gov, International Clinical Trials Registry Platform (ICTRP), ClinicalStudyResults.org and Google. REVIEW METHODS Studies eligible for inclusion in this IPD meta-analysis were randomised controlled trials (RCTs) in children up to 12 years of age diagnosed with recurrent AOM and/or persistent OME in which adenoidectomy (with or without grommets) was compared with non-surgical treatment or grommets alone. The final selection of eligible studies and the quality assessment were carried out according to standard methods and disagreement was resolved by discussion. RESULTS A total of 503 articles were identified of which 10 trials were included in the meta-analysis; eight of these were at a low risk of bias and two were at moderate risk. The primary outcome was failure at 12 months, defined by a set of persisting symptoms and signs. In the prognostic analysis 56% of those children referred for adenoidectomy (but randomised to the non-surgical group) failed to improve (38% of the children with recurrent AOM and 89% of the children with persistent OME). Children who had adenoidectomy had a greater chance of clinical improvement. The size of that effect is, in general, small but persists for at least 2 years. Two subgroups of children are most likely to benefit from adenoidectomy: first, children aged < 2 years with recurrent AOM - 16% of those who had adenoidectomy failed at 12 months whereas 27% of those who did not have adenoidectomy failed [rate difference (RD) 12%, 95% confidence interval (Cl) 6% to 18%; number needed to treat (NNT) = 9]; second, children aged ≥ 4 years with persistent OME - 51% of those who had adenoidectomy failed at 12 months whereas 70% of those who did not have adenoidectomy failed (RD 19%, 95% Cl 12% to 26%; NNT = 6). No significant benefit of adenoidectomy was found in children aged ≥ 2 years with recurrent AOM and children aged < 4 years with persistent OME. LIMITATIONS The need to use a composite end point and the limited number of subgroup variables that could be studied are factors that reduce the robustness of these results; however, we do not believe that this reduces the validity of the conclusions. CONCLUSIONS Adenoidectomy is most beneficial in children with persistent OME aged ≥ 4 years. A smaller beneficial effect was found in children with recurrent AOM aged < 2 years. Consideration must be given to the balance between benefits and harms. Future research is required in a number of key areas, including defining the best methods of selecting, developing and administering patient-reported outcome measures to assess the value of treatments for children with persistent OME and recurrent AOM and upper respiratory infections; investigating the clinical effectiveness and cost-effectiveness of hearing aids (air or bone conduction) and the use of interventions to improve classroom acoustics for children with different degrees of persistence and severity of hearing loss associated with OME; and investigating why professionals' and parents'/carers' treatment preferences vary so much both nationally and internationally. We do not understand why adenoidectomy works in different subgroups at different ages, nor its effects in special populations, such as children with Down syndrome. We also need further research on the impact and optimal management of otitis media in these special situations and others, such as in children with a cleft palate or developmental problems. STUDY REGISTRATION The study is registered as PROSPERO CRD42011001549. FUNDING The National Institute for Health Research Health Technology Assessment programme. PMID:24438691

[The specific microbiological and clinical features of acute otitis media].

PubMed

Gurov, A V; Levina, Yu V; Guseva, A L; Elchueva, Z G; Efimova, S P; Gordienko, M V

The objective of the present study was to elucidate the specific features of the clinical course of acute otitis media as well as the peculiarities of the vestibular function and the microbial paysage associated with this pathological condition under the present-day conditions. The study included 135 patients presenting with acute otitis media (AOM) at different stages of the disease. The discharge obtained from the tympanic cavity of all the patients was examined with the use of polymerase chain reaction in real time, audiological and vestibulogical methods. The distinctive features of acute otitis medium associated with Streptococcus pneumoniae infection were found to be the intense pain syndrome with the symptoms of intoxication, well apparent inflammatory changes in the tympanic membrane as revealed by otoscopy, the increased frequency of sensorineural impairment of hearing, and the characteristic type B tympanometric curve. Typical of AOM associated with Haemophilus influenza infection are the mild pain syndrome, weak changes in the tympanic membrane as revealed by otoscopy, conductive hearing loss, and the type C tympanometric curve.

Construction and characterization of ultraviolet acousto-optic based femtosecond pulse shapers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mcgrane, Shawn D; Moore, David S; Greenfield, Margo T

2008-01-01

We present all the information necessary for construction and characterization of acousto optic pulse shapers, with a focus on ultraviolet wavelengths, Various radio-frequency drive configurations are presented to allow optimization via knowledgeable trade-off of design features. Detailed performance characteristics of a 267 nm acousto-optic modulator (AOM) based pulse shaper are presented, Practical considerations for AOM based pulse shaping of ultra-broad bandwidth (sub-10 fs) amplified femtosecond pulse shaping are described, with particular attention paid to the effects of the RF frequency bandwidth and optical frequency bandwidth on the spatial dispersion of the output laser pulses.

[Changes of expression of miR-155 in colitis-associated colonic carcinogenesis].

PubMed

Li, Weiwei; Han, Wenxiao; Zhao, Xinhua; Wang, Hongying

2014-04-01

To investigate the changes of miR-155 and its target genes in colitis-associated carcinogenesis. Colitis-associated colon cancer was induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in C57BL/6 mice. Mice of three different stages during the development of colon cancer were obtained, named AD1, AD2 and AD3, respectively. A control group of mice without any treatment and a DSS only group representing chronic inflammation without cancer were set up as well. Colon tissue was collected and expression of miR-155 in the colon tissues was measured by real-time fluorescent quantitative PCR. TargetScan and PicTar were used to predict potential target genes of miR-155, which were then preliminarily screened with our gene expression microarray database of AOM-DSS mouse model. Regular PCR was used to confirm the changes of the expression of these potential target genes in AOM-DSS mouse model. Colitis-associated colon cancer was effectively induced by azoxymethane and dextran sulfate sodium in C57BL/6 mice. Histological examination revealed that the evolution process was sequentially from normal, mild dysplasia, moderate dysplasia, and severe dysplasia to adenocarcinoma in the AOM-DSS mouse model. The level of miR-155 was gradually elevated with the formation of colitis-associated colon cancer. There was no significant difference between the levels of miR-155 expression in the DSS group (0.005 6 ± 0.003 7) and control group (0.012 0 ± 0.005 1) (P > 0.05), but the level of miR-155 in the AD3 group (0.054 4 ± 0.027 0) was significantly higher than that of the DSS group (0.005 6 ± 0.003 7)(P < 0.01). No significant change of miR-155 expression was found in the DSS only group. The relative expression levels of miR-155 in the control group, DSS only group and AD3 group were 0.012 0 ± 0.005 1, 0.005 6 ± 0.003 7, 0.054 4 ± 0.027 0, respectively. Data analysis with the gene expression microarray showed that Tle4, Kcna1, Itk, Bcorl1, Cacna1c, Rspo2 and Foxo3 were potential target genes of miR-155 in the AOM-DSS mouse model. Changes of Kcna1 and Cacna1c in the AOM-DSS mouse model were validated to be consistent with the changes obtained with the gene expression microarray. The up-regulation of miR-155 is related to colitis-associated carcinogenesis, but is irrelevant to chronic inflammation in the mouse model.

Combination of atorvastatin with sulindac or naproxen profoundly inhibits colonic adenocarcinomas by suppressing the p65/β-catenin/cyclin D1 signaling pathway in rats

PubMed Central

Suh, Nanjoo; Reddy, Bandaru S.; DeCastro, Andrew; Paul, Shiby; Lee, Hong Jin; Smolarek, Amanda K.; So, Jae Young; Simi, Barbara; Wang, Chung Xiou; Janakiram, Naveena B.; Steele, Vernon; Rao, Chinthalapally V.

2011-01-01

Evidence supports the protective role of non-steroidal anti-inflammatory drugs (NSAIDs) and statins against colon cancer. Experiments were designed to evaluate the efficacies atorvastatin and NSAIDs administered individually and in combination against colon tumor formation. F344 rats were fed AIN-76A diet and colon tumors were induced with azoxymethane (AOM). One week after the second AOM-treatment groups of rats were fed diets containing atorvastatin (200 ppm), sulindac (100 ppm) or naproxen (150 ppm), or their combinations with low-dose atorvastatin (100 ppm) for 45 weeks. Administration of atorvastatin at 200 ppm significantly suppressed both adenocarcinoma incidence (52% reduction, p=0.005) and multiplicity (58% reduction, p=0.008). Most importantly, colon tumor multiplicities were profoundly decreased (80–85% reduction, p<0.0001) when given low-dose atorvastatin with either sulindac or naproxen. Also, a significant inhibition of colon tumor incidence was observed when given a low-dose atorvastatin with either sulindac (p=0.001) or naproxen (p =0.0005). Proliferation markers, proliferating cell nuclear antigen, cyclin D1 and β-catenin in tumors of rats exposed to sulindac, naproxen, atorvastatin, and/or combinations showed a significant suppression. Importantly, colon adenocarcinomas from atorvastatin and NSAIDs fed animals showed reduced key inflammatory markers, inducible nitric oxide synthase and cyclooxygenase-2, phospho-p65, as well as inflammatory cytokines, TNF-α, IL-1β, and IL-4. Overall, this is the first report on the combination treatment using low-dose atorvastatin with either low dose sulindac or naproxen, which greatly suppress the colon adenocarcinoma incidence and multiplicity. Our results suggest that low-dose atorvastatin with sulindac or naproxen might potentially be useful combinations for colon cancer prevention in humans. PMID:21764859

Preventive effects of curcumin on the development of azoxymethane-induced colonic preneoplastic lesions in male C57BL/KsJ-db/db obese mice.

PubMed

Kubota, Masaya; Shimizu, Masahito; Sakai, Hiroyasu; Yasuda, Yoichi; Terakura, Daishi; Baba, Atsushi; Ohno, Tomohiko; Tsurumi, Hisashi; Tanaka, Takuji; Moriwaki, Hisataka

2012-01-01

Obesity-related metabolic abnormalities include a state of chronic inflammation and adipocytokine imbalance, which increase the risk of colon cancer. Curcumin, a component of turmeric, exerts both cancer preventive and antiinflammatory properties. Curcumin is also expected to have the ability to reverse obesity-related metabolic derangements. The present study examined the effects of curcumin on the development of azoxymethane (AOM)-induced colonic premalignant lesions in C57BL/KsJ-db/db (db/db) obese mice. Feeding with a diet containing 0.2% and 2.0% curcumin caused a significant reduction in the total number of colonic premalignant lesions compared with basal diet-fed mice. The expression levels of tumor necrosis factor-α, interleukin-6, and cyclooxygenase-2 (COX-2) mRNAs on the colonic mucosa of AOM-treated mice were significantly decreased by curcumin administration. Dietary feeding with curcumin markedly activated AMP-activated kinase, decreased the expression of COX-2 protein, and inhibited nuclear factor-κB activity on the colonic mucosa of AOM-treated mice. Curcumin also increased the serum levels of adiponectin while conversely decreasing the serum levels of leptin and the weights of fat. In conclusion, curcumin inhibits the development of colonic premalignant lesions in an obesity-related colorectal carcinogenesis model, at least in part, by attenuating chronic inflammation and improving adipocytokine imbalance. Curcumin may be useful in the chemoprevention of colorectal carcinogenesis in obese individuals.

Facial palsy in children: emergency department management and outcome.

PubMed

Wang, Cheng-Hsien; Chang, Yu-Che; Shih, Hong-Mo; Chen, Chun-Yu; Chen, Jih-Chang

2010-02-01

To describe the characteristics of children who present to an emergency department (ED) with facial palsy and determine the association of outcome with etiology, degree of initial paralysis, and ED management. This was a retrospective cohort study of children who presented to an ED with facial nerve paralysis (FNP). There were 85 patients with a mean age of 8.0 (SD, 6.1) years; 60% (n = 51) of the patients were male, and 65.9% (n = 56) were admitted to the hospital. Bell palsy (50.6%) was the most common etiology followed by infectious (22.4%), traumatic (16.5%), congenital (7.1%), and neoplastic etiologies (3.5%). Patients with Bell palsy had shorter recovery times (P = 0.049), and traumatic cases required a longer time for recovery (P = 0.016). Acute otitis media (AOM)-related pediatric FNP had shorter recovery times than non-AOM-related cases (P = 0.005) in infectious group. Patients given steroid therapy did not have a shorter recovery time (P = 0.237) or a better recovery (P = 0.269). There was no difference in recovery rate of pediatric patients with Bell palsy between hospitalization or not (P = 0.952). Bell palsy, infection, and trauma were most common etiologies of pediatric FNP. Recovery times were shorter in pediatric patients with Bell palsy and AOM-related FNP, whereas recovery took longer in traumatic cases. Steroid therapy did not seem beneficial for pediatric FNP. Hospitalization is not indicated for pediatric patients with Bell palsy.

Possible roles of uncultured archaea in carbon cycling in methane-seep sediments

NASA Astrophysics Data System (ADS)

Yoshinaga, Marcos Y.; Lazar, Cassandre S.; Elvert, Marcus; Lin, Yu-Shih; Zhu, Chun; Heuer, Verena B.; Teske, Andreas; Hinrichs, Kai-Uwe

2015-09-01

Studies on microbial carbon cycling uniformly confirm that anaerobic methane-oxidizing archaea (ANME) and sulfate-reducing bacteria represent the dominant and most active fraction of the sedimentary microbial community in methane-seep sediments. However, little is known about other frequently observed and abundant microbial taxa, their role in carbon cycling and association with the anaerobic oxidation of methane (AOM). Here, we provide a comprehensive characterization of stable carbon isotopes (δ13C) from several intact polar lipid (IPL) classes and metabolite pools in a downcore profile at a cold seep within the oxygen minimum zone off Pakistan. We aimed to evaluate microbial carbon metabolism using IPLs in relation to redox conditions, metabolites and 16S rRNA gene libraries. The 13C-depleted signature of carbon pools and microbial metabolites in pore waters (e.g., dissolved inorganic carbon, lactate and acetate) demonstrated high accumulation of AOM-associated biomass and subsequent turnover thereof. ANMEs accounted for a small fraction of the archaeal 16S rRNA gene survey, whereas sequences of other uncultured benthic archaea dominated the clone libraries, particularly the Marine Benthic Group D. On the basis of lipid diversity and carbon isotope information, we suggest that structurally diverse phospho- and glycolipids, including the recently identified unsaturated tetraethers that are particularly abundant in this setting, are likely derived from archaea other than ANMEs. Through the evaluation of δ13C values of individual IPL, our results indicate heterotrophy as a possible metabolic pathway of archaea in these AOM-dominated sediments.

Adenoidectomy with or without grommets for children with otitis media: an individual patient data meta-analysis.

PubMed

Boonacker, Chantal W B; Rovers, Maroeska M; Browning, George G; Hoes, Arno W; Schilder, Anne G M; Burton, Martin J

2014-01-01

Otitis media (OM) is a leading cause of medical consultations, antibiotic prescription and surgery in children. The surgical procedures offered to children with recurrent or persistent OM are insertion of grommets, adenoidectomy or a combination of the two. There is clear National Institute for Health and Care Excellence guidance for the use of grommets in subgroups of children with persistent OM with effusion (OME), but similar guidance is not available for adenoidectomy, either in persistent OME or in recurrent acute OM (AOM). (1) To develop a model to predict the risk of children referred for adenoidectomy having a prolonged duration of their OM. Then, (2a) to evaluate the overall effect of adenoidectomy, with or without grommets, on OM using individual patient data (IPD) and (2b) to identify those subgroups of children who are most likely to benefit from adenoidectomy with or without grommets. A number of electronic databases were searched from their inception including the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), metaRegister of Current Controlled Trials (mRCT), ClinicalTrials.gov, International Clinical Trials Registry Platform (ICTRP), ClinicalStudyResults.org and Google. Studies eligible for inclusion in this IPD meta-analysis were randomised controlled trials (RCTs) in children up to 12 years of age diagnosed with recurrent AOM and/or persistent OME in which adenoidectomy (with or without grommets) was compared with non-surgical treatment or grommets alone. The final selection of eligible studies and the quality assessment were carried out according to standard methods and disagreement was resolved by discussion. A total of 503 articles were identified of which 10 trials were included in the meta-analysis; eight of these were at a low risk of bias and two were at moderate risk. The primary outcome was failure at 12 months, defined by a set of persisting symptoms and signs. In the prognostic analysis 56% of those children referred for adenoidectomy (but randomised to the non-surgical group) failed to improve (38% of the children with recurrent AOM and 89% of the children with persistent OME). Children who had adenoidectomy had a greater chance of clinical improvement. The size of that effect is, in general, small but persists for at least 2 years. Two subgroups of children are most likely to benefit from adenoidectomy: first, children aged < 2 years with recurrent AOM - 16% of those who had adenoidectomy failed at 12 months whereas 27% of those who did not have adenoidectomy failed [rate difference (RD) 12%, 95% confidence interval (Cl) 6% to 18%; number needed to treat (NNT) = 9]; second, children aged ≥ 4 years with persistent OME - 51% of those who had adenoidectomy failed at 12 months whereas 70% of those who did not have adenoidectomy failed (RD 19%, 95% Cl 12% to 26%; NNT = 6). No significant benefit of adenoidectomy was found in children aged ≥ 2 years with recurrent AOM and children aged < 4 years with persistent OME. The need to use a composite end point and the limited number of subgroup variables that could be studied are factors that reduce the robustness of these results; however, we do not believe that this reduces the validity of the conclusions. Adenoidectomy is most beneficial in children with persistent OME aged ≥ 4 years. A smaller beneficial effect was found in children with recurrent AOM aged < 2 years. Consideration must be given to the balance between benefits and harms. Future research is required in a number of key areas, including defining the best methods of selecting, developing and administering patient-reported outcome measures to assess the value of treatments for children with persistent OME and recurrent AOM and upper respiratory infections; investigating the clinical effectiveness and cost-effectiveness of hearing aids (air or bone conduction) and the use of interventions to improve classroom acoustics for children with different degrees of persistence and severity of hearing loss associated with OME; and investigating why professionals' and parents'/carers' treatment preferences vary so much both nationally and internationally. We do not understand why adenoidectomy works in different subgroups at different ages, nor its effects in special populations, such as children with Down syndrome. We also need further research on the impact and optimal management of otitis media in these special situations and others, such as in children with a cleft palate or developmental problems. The study is registered as PROSPERO CRD42011001549. The National Institute for Health Research Health Technology Assessment programme.

Gas hydrate decomposition recorded by authigenic barite at pockmark sites of the northern Congo Fan

NASA Astrophysics Data System (ADS)

Kasten, Sabine; Nöthen, Kerstin; Hensen, Christian; Spieß, Volkhard; Blumenberg, Martin; Schneider, Ralph R.

2012-12-01

The geochemical cycling of barium was investigated in sediments of pockmarks of the northern Congo Fan, characterized by surface and subsurface gas hydrates, chemosynthetic fauna, and authigenic carbonates. Two gravity cores retrieved from the so-called Hydrate Hole and Worm Hole pockmarks were examined using high-resolution pore-water and solid-phase analyses. The results indicate that, although gas hydrates in the study area are stable with respect to pressure and temperature, they are and have been subject to dissolution due to methane-undersaturated pore waters. The process significantly driving dissolution is the anaerobic oxidation of methane (AOM) above the shallowest hydrate-bearing sediment layer. It is suggested that episodic seep events temporarily increase the upward flux of methane, and induce hydrate formation close to the sediment surface. AOM establishes at a sediment depth where the upward flux of methane from the uppermost hydrate layer counterbalances the downward flux of seawater sulfate. After seepage ceases, AOM continues to consume methane at the sulfate/methane transition (SMT) above the hydrates, thereby driving the progressive dissolution of the hydrates "from above". As a result the SMT migrates downward, leaving behind enrichments of authigenic barite and carbonates that typically precipitate at this biogeochemical reaction front. Calculation of the time needed to produce the observed solid-phase barium enrichments above the present-day depths of the SMT served to track the net downward migration of the SMT and to estimate the total time of hydrate dissolution in the recovered sediments. Methane fluxes were higher, and the SMT was located closer to the sediment surface in the past at both sites. Active seepage and hydrate formation are inferred to have occurred only a few thousands of years ago at the Hydrate Hole site. By contrast, AOM-driven hydrate dissolution as a consequence of an overall net decrease in upward methane flux seems to have persisted for a considerably longer time at the Worm Hole site, amounting to a few tens of thousands of years.

The FISH-SIMS Approach: Isotopic Imprints of Methane in Diverse Microbial Assemblages

NASA Astrophysics Data System (ADS)

Orphan, V. J.; House, C. H.; Hinrichs, K.; McKeegan, K. D.; Paull, C.; Ussler, W.; DeLong, E. F.

2001-12-01

One of the more important biogeochemical processes influencing carbon turnover in continental margin environments and cold seeps is the anaerobic oxidation of methane (AOM). Although there is convincing biogeochemical evidence for archaeal/sulfate-reducer cooperative involvement in AOM, methane-consuming anaerobic microorganisms have eluded identification until only very recently. Parallel phylogenetic gene surveys and isotopic determination of lipid biomarkers in methane-rich seep sediments suggested that diverse archaeal and bacterial assemblages are involved in AOM. Specifically, a novel clade of Archaea related to known methanogens (ANME-1 group), as well as microorganisms affiliated with the Methanosarcinales (ANME-2 group) and their syntrophic sulfate-reducing bacterial partner affiliated with the Desulfosarcina, have been identified as likely candidate methane-oxidizing microorganisms. Both 16S rDNA and lipid analyses provide only circumstantial evidence linking these specific groups to AOM, however, because they are based on bulk analyses of whole sediments, rather than on the level of single microorganisms. In this study, we provide the first concrete evidence directly linking two distinct groups of Archaea, the uncultured consortium archaeal ANME-2/ bacterial Desulfosarcina spp. and the archaeal ANME-1 to methane consumption in anoxic marine sediments. Using a novel approach combining fluorescent in situ hybridization (FISH) and secondary ion mass spectrometry (SIMS), we identified aggregations of ANME-2/ Desulfosarcina and single cells and aggregates of ANME-1 from methane seep sediments and directly determined the carbon stable isotopic composition for the individual cells and cell aggregates. Both archaeal groups ANME-1 and ANME-2 displayed isotopic signatures suggestive of methane assimilation, with extreme 13C depletion (down to -97 per mil). In comparison, the carbon isotopic composition of microorganisms from the same sample not targeted with either the archaeal ANME-1 or ANME-2 specific rRNA probe sets had 13C values averaging -30 per mil. Interestingly, large bacterial filaments resembling sulfide-oxidizing Beggiatoa were slightly more depleted in 13C (approx. -50 per mil), and may signify ecosystem-wide incorporation of methane-derived endproducts. The combined application of FISH and SIMS serves as a new useful tool in geomicrobiology for deciphering the metabolic function of environmental microorganisms in situ.

Interstitial ion homeostasis and acid-base balance are maintained in oedematous brain of mice with acute toxic liver failure.

PubMed

Obara-Michlewska, Marta; Ding, Fengfei; Popek, Mariusz; Verkhratsky, Alexei; Nedergaard, Maiken; Zielinska, Magdalena; Albrecht, Jan

2018-05-14

Acute toxic liver failure (ATLF) rapidly leads to brain oedema and neurological decline. We evaluated the ability of ATLF-affected brain to control the ionic composition and acid-base balance of the interstitial fluid. ATLF was induced in 10-12 weeks old male C57Bl mice by single intraperitoneal (i.p.) injection of 100 μg/g azoxymethane (AOM). Analyses were carried out in cerebral cortex of precomatous mice 20-24 h after AOM administration. Brain fluid status was evaluated by measuring apparent diffusion coefficient [ADC] using NMR spectroscopy, Evans Blue extravasation, and accumulation of an intracisternally-injected fluorescent tracer. Extracellular pH ([pH] e ) and ([K + ] e ) were measured in situ with ion-sensitive microelectrodes. Cerebral cortical microdialysates were subjected to photometric analysis of extracellular potassium ([K + ] e ), sodium ([Na + ] e ) and luminometric assay of extracellular lactate ([Lac] e ). Potassium transport in cerebral cortical slices was measured ex vivo as 86 Rb uptake. Cerebral cortex of AOM-treated mice presented decreased ADC supporting the view that ATLF-induced brain oedema is primarily cytotoxic in nature. In addition, increased Evans blue extravasation indicated blood brain barrier leakage, and increased fluorescent tracer accumulation suggested impaired interstitial fluid passage. However, [K + ] e , [Na + ] e , [Lac] e , [pH] e and potassium transport in brain of AOM-treated mice was not different from control mice. We conclude that in spite of cytotoxic oedema and deregulated interstitial fluid passage, brain of mice with ATLF retains the ability to maintain interstitial ion homeostasis and acid-base balance. Tentatively, uncompromised brain ion homeostasis and acid-base balance may contribute to the relatively frequent brain function recovery and spontaneous survival rate in human patients with ATLF. Copyright © 2018. Published by Elsevier Ltd.

The Role of Curcumin in Modulating Colonic Microbiota During Colitis and Colon Cancer Prevention.

PubMed

McFadden, Rita-Marie T; Larmonier, Claire B; Shehab, Kareem W; Midura-Kiela, Monica; Ramalingam, Rajalakshmy; Harrison, Christy A; Besselsen, David G; Chase, John H; Caporaso, J Gregory; Jobin, Christian; Ghishan, Fayez K; Kiela, Pawel R

2015-11-01

Intestinal microbiota influences the progression of colitis-associated colorectal cancer. With diet being a key determinant of the gut microbial ecology, dietary interventions are an attractive avenue for the prevention of colitis-associated colorectal cancer. Curcumin is the most active constituent of the ground rhizome of the Curcuma longa plant, which has been demonstrated to have anti-inflammatory, antioxidative, and antiproliferative properties. Il10 mice on 129/SvEv background were used as a model of colitis-associated colorectal cancer. Starting at 10 weeks of age, wild-type or Il10 mice received 6 weekly intraperitoneal injections of azoxymethane (AOM) or phosphate-buffered saline (PBS) and were started on either a control or a curcumin-supplemented diet. Stools were collected every 4 weeks for microbial community analysis. Mice were killed at 30 weeks of age. Curcumin-supplemented diet increased survival, decreased colon weight/length ratio, and, at 0.5%, entirely eliminated tumor burden. Although colonic histology indicated improvement with curcumin, no effects of mucosal immune responses have been observed in PBS/Il10 mice and limited effects were seen in AOM/Il10 mice. In wild-type and in Il10 mice, curcumin increased bacterial richness, prevented age-related decrease in alpha diversity, increased the relative abundance of Lactobacillales, and decreased Coriobacterales order. Taxonomic profile of AOM/Il10 mice receiving curcumin was more similar to those of wild-type mice than those fed control diet. In AOM/Il10 model, curcumin reduced or eliminated colonic tumor burden with limited effects on mucosal immune responses. The beneficial effect of curcumin on tumorigenesis was associated with the maintenance of a more diverse colonic microbial ecology.

The Role of Curcumin in Modulating Colonic Microbiota During Colitis and Colon Cancer Prevention

PubMed Central

McFadden, Rita-Marie T.; Larmonier, Claire B.; Shehab, Kareem W.; Midura-Kiela, Monica; Ramalingam, Rajalakshmy; Harrison, Christy A.; Besselsen, David G.; Chase, John H.; Caporaso, J. Gregory; Jobin, Christian; Ghishan, Fayez K.; Kiela, Pawel R.

2015-01-01

Background Intestinal microbiota influences the progression of colitis-associated colorectal cancer (CAC). With diet being a key determinant of the gut microbial ecology, dietary interventions are an attractive avenue for the prevention of CAC. Curcumin is the most active constituent of the ground rhizome of the Curcuma Longa plant, which has been demonstrated to have anti-inflammatory, anti-oxidative and anti-proliferative properties. Methods Il10−/− mice on 129/SvEv background were used as a model of CAC. Starting at 10 weeks of age, WT or Il10−/− mice received six weekly i.p. injections of azoxymethane (AOM) or saline, and were started on either a control or curcumin-supplemented diet. Stools were collected every 4 weeks for microbial community analysis. Mice were sacrificed at 30 weeks of age. Results Curcumin-supplemented diet increased survival, decreased colon weight/length ratio, and at 0.5%, entirely eliminated tumor burden. Although colonic histology indicated improvement with curcumin, no effects of mucosal immune responses have been observed in PBS/Il10−/− mice, and limited effects were seen in AOM/Il10−/− mice. In WT and in Il10−/− mice, curcumin increased bacterial richness, prevented age-related decrease in alpha diversity, increased the relative abundance of Lactobacillales, and decreased Coriobacterales order. Taxonomic profile of AOM/Il10−/− mice receiving curcumin was more similar to those of wild-type mice than those fed control diet. Conclusions In AOM/Il10−/− model, curcumin reduced or eliminated colonic tumor burden with limited effects on mucosal immune responses. The beneficial effect of curcumin on tumorigenesis was associated with the maintenance of a more diverse colonic microbial ecology. PMID:26218141

Amoxicillin/clavulanate for infections in infants and children: past, present and future.

PubMed

Klein, Jerome O

2003-08-01

Chemical synthesis of the penicillin nucleus in the 1950s made introduction of a broad array of new and important antimicrobials, including ampicillin and amoxicillin, possible. Ampicillin was introduced in 1962 in oral and parenteral forms as the first of the semisynthetic penicillins to provide increased activity against Gram-negative bacteria. Amoxicillin replaced oral ampicillin beginning in 1974 because amoxicillin resulted in higher and more prolonged serum concentrations than did equivalent doses of ampicillin. Amoxicillin/clavulanate (Augmentin) was introduced in the United States in 1984 to enhance the activity of amoxicillin by addition of the beta-lactamase inhibitor, clavulanic acid. During the past 20 years, amoxicillin/clavulanate has proven effective for a variety of pediatric infectious diseases, particularly acute otitis media (AOM). In 2001, a new pediatric formulation, high dose amoxicillin/clavulanate (Augmentin ES-600) was approved for use in the United States. The high dose preparation addressed the needs of pediatricians by providing greater amounts of amoxicillin while maintaining the same daily dose of clavulanic acid as the regular strength formulation. Doubling the dose of amoxicillin for management of recurrent and persistent AOM was recommended in 1999 by the Centers for Disease Control and Prevention because of concern about the increased incidence of nonsusceptible strains of Streptococcus pneumoniae. The original formulation combined amoxicillin/clavulanate in a 4:1 ratio and was followed by a 7:1 ratio formulation. The high dose formulation (600 mg of amoxicillin per 5 ml) provides a 14:1 ratio of amoxicillin to clavulanate. Although management of AOM will likely undergo changes in the coming years, amoxicillin is expected to remain first line therapy for AOM. For children who fail initial therapy with amoxicillin, high dose amoxicillin/clavulanate, an oral cephalosporin or parenteral ceftriaxone is recommended.

Impact of anaerobic oxidation of methane on the geochemical cycle of redox-sensitive elements at cold-seep sites of the northern South China Sea

NASA Astrophysics Data System (ADS)

Hu, Yu; Feng, Dong; Liang, Qianyong; Xia, Zhen; Chen, Linying; Chen, Duofu

2015-12-01

Cold hydrocarbon seepage is a frequently observed phenomenon along continental margins worldwide. However, little is known about the impact of seeping fluids on the geochemical cycle of redox-sensitive elements. Pore waters from four gravity cores (D-8, D-5, D-7, and D-F) collected from cold-seep sites of the northern South China Sea were analyzed for SO42-, Mg2+, Ca2+, Sr2+, dissolved inorganic carbon (DIC), δ13CDIC, dissolved Fe, Mn, and trace elements (e.g. Mo, U). The sulfate concentration-depth profiles, δ13CDIC values and (ΔDIC+ΔCa2++ΔMg2+)/ΔSO42- ratios suggest that organoclastic sulfate reduction (OSR) is the dominant process in D-8 core. Besides OSR, anaerobic oxidation of methane (AOM) is partially responsible for depletion of sulfate at D-5 and D-7 cores. The sulfate consumption at D-F core is predominantly caused by AOM. The depth of sulfate-methane interface (SMI) and methane diffusive flux of D-F core are calculated to be ~7 m and 0.035 mol m-2 yr-1, respectively. The relatively shallow SMI and high methane flux at D-F core suggest the activity of gas seepage in this region. The concentrations of dissolved uranium (U) were inferred to decrease significantly within the iron reduction zone. It seems that AOM has limited influence on the U geochemical cycling. In contrast, a good correlation between the consumption of sulfate and the removal of molybdenum (Mo) suggests that AOM has a significantly influence on the geochemical cycle of Mo at cold seeps. Accordingly, cold seep environments may serve as an important potential sink in the marine geochemical cycle of Mo.

Chemoprevention of azoxymethane-initiated colon cancer in rat by using a novel polymeric nanocarrier--curcumin.

PubMed

Alizadeh, Ali Mohammad; Khaniki, Mahmood; Azizian, Saleh; Mohaghgheghi, Mohammad Ali; Sadeghizadeh, Majid; Najafi, Farhood

2012-08-15

Curcumin is a potential natural anticancer drug with limited bioavailability due to the lack of solubility in aqueous solvents. The present study is designed to investigate the preventive effects of polymeric nanocarrier-curcumin (PNCC) on colon carcinogenesis in an azoxymethane-induced rat tumor. Forty rats were divided into control, curcumin- and PNCC-treated groups. Animals received azoxymethane (AOM) as a carcinogenic agent (15 mg/kg, s.c.) weekly for two consecutive weeks. They were given curcumin 0.2% and PNCC two weeks before till 14 weeks after the last injection of AOM. In the end, post euthanasia, the entire gastrointestinal tract was scrutinized for tumors, and the rest of the body for metastatic deposits. Tumor number, size and location were characterized. The histopathological and immunohistochemistry examinations were also performed on colon tissue. In vivo, curcumin nanoparticles inhibited colon cancer growth in animal model. The tumors incidence and number decreased by nanocurcumin comparison with control. Furthermore, the nuclear/cytoplasmic ratio, epithelial stratification, nuclear dispolarity, goblet depletion, structural abnormality, and the expression of Beta-catenin and Bcl-2 proteins were reduced in PNCC compared to others groups (P<0.05). In addition, Bax protein expression was significantly increased in PNCC in comparison with control and curcumin-treated groups (P<0.001). The present study demonstrated the potential anticancer effects of PNCC in a typical animal model. The results provide evidence that nanopolymeric curcumin exerts a significant chemopreventive effect on AOM-initiated colon cancer through cell proliferation inhibition and apoptosis induction. More investigations are needed to confirm its safety for human use. Copyright © 2012 Elsevier B.V. All rights reserved.

Mass Spectrometry and Fourier Transform Infrared Spectroscopy for Analysis of Biological Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Timothy J.

Time-of-flight mass spectrometry along with statistical analysis was utilized to study metabolic profiles among rats fed resistant starch (RS) diets. Fischer 344 rats were fed four starch diets consisting of 55% (w/w, dbs) starch. A control starch diet consisting of corn starch was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. A subgroup received antibiotic treatment to determine if perturbations in the gut microbiome were long lasting. A second subgroup was treated with azoxymethane (AOM), a carcinogen. At the end of the eight weekmore » study, cecal and distal-colon contents samples were collected from the sacrificed rats. Metabolites were extracted from cecal and distal colon samples into acetonitrile. The extracts were then analyzed on an accurate-mass time-of-flight mass spectrometer to obtain their metabolic profile. The data were analyzed using partial least-squares discriminant analysis (PLS-DA). The PLS-DA analysis utilized a training set and verification set to classify samples within diet and treatment groups. PLS-DA could reliably differentiate the diet treatments for both cecal and distal colon samples. The PLS-DA analyses of the antibiotic and no antibiotic treated subgroups were well classified for cecal samples and modestly separated for distal-colon samples. PLS-DA analysis had limited success separating distal colon samples for rats given AOM from those not treated; the cecal samples from AOM had very poor classification. Mass spectrometry profiling coupled with PLS-DA can readily classify metabolite differences among rats given RS diets.« less

High-resolution time-of-flight mass spectrometry fingerprinting of metabolites from cecum and distal colon contents of rats fed resistant starch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Timothy J.; Jones, Roger W.; Ai, Yongfeng

Time-of-flight mass spectrometry along with statistical analysis was utilized to study metabolic profiles among rats fed resistant starch (RS) diets. Fischer 344 rats were fed four starch diets consisting of 55 % (w/w, dbs) starch. A control starch diet consisting of corn starch was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. A subgroup received antibiotic treatment to determine if perturbations in the gut microbiome were long lasting. A second subgroup was treated with azoxymethane (AOM), a carcinogen. At the end of the 8-weekmore » study, cecal and distal colon content samples were collected from the sacrificed rats. Metabolites were extracted from cecal and distal colon samples into acetonitrile. The extracts were then analyzed on an accurate-mass time-of-flight mass spectrometer to obtain their metabolic profile. The data were analyzed using partial least-squares discriminant analysis (PLS-DA). The PLS-DA analysis utilized a training set and verification set to classify samples within diet and treatment groups. PLS-DA could reliably differentiate the diet treatments for both cecal and distal colon samples. The PLS-DA analyses of the antibiotic and no antibiotic-treated subgroups were well classified for cecal samples and modestly separated for distal colon samples. PLS-DA analysis had limited success separating distal colon samples for rats given AOM from those not treated; the cecal samples from AOM had very poor classification. Mass spectrometry profiling coupled with PLS-DA can readily classify metabolite differences among rats given RS diets.« less

Prechlorination of algae-laden water: The effects of transportation time on cell integrity, algal organic matter release, and chlorinated disinfection byproduct formation.

PubMed

Qi, Jing; Lan, Huachun; Liu, Ruiping; Miao, Shiyu; Liu, Huijuan; Qu, Jiuhui

2016-10-01

The prechlorination-induced algal organic matter (AOM) released from Microcystis aeruginosa (M. aeruginosa) cells has been reported to serve as a source of precursors for chlorinated disinfection byproducts (DBPs). However, previous studies have mainly focused on the precursors either extracted directly from the cell suspension or derived immediately after algal suspension prechlorination. This study aims to investigate the impacts of water transportation time after algal suspension prechlorination on cell integrity, AOM release, and DBP formation during the dissolved phase chlorination. The damage to cell integrity after prechlorination was indicated to depend not only on chlorine dose but also on transportation time. The highest dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) values were observed at 2 mg/L chlorine preoxidation before transportation, but were obtained at 0.4 mg/L chlorine after 480-min simulated transportation. The variation of DON with transportation time was indicated to be mainly influenced by the small molecular weight nitrogenous organic compounds, such as amino acids. Additionally, formation of the corresponding chlorinated carbonaceous disinfection byproducts (C-DBPs) and nitrogenous disinfection byproducts (N-DBPs) during the dissolved phase chlorination showed the same variation tendency as DOC and DON respectively. The highest C-DBP (98.4 μg/L) and N-DBP (5.5 μg/L) values were obtained at 0.4 mg/L chlorine preoxidation after 480-min simulated transportation. Therefore, when prechlorination is applied for algae-laden water pretreatment, not only chlorine dose but also transportation time needs to be considered with regard to their effects on cell integrity, AOM release, and chlorinated DBP formation. Copyright © 2016. Published by Elsevier Ltd.

Tumor promotion by dietary fat in azoxymethane-induced colon carcinogenesis in female F344 rats: influence of amount and source of dietary fat.

PubMed

Reddy, B S; Maeura, Y

1984-03-01

The promoting effect of dietary corn oil (CO), safflower oil (SO), olive oil (OO), coconut oil (CC), and medium-chain triglycerides (MCT) on azoxymethane (AOM)-induced colon tumors was studied in female F344 rats. The animals were fed low-fat diets containing 5% CO, 5% SO, or 5% OO 2 weeks before, during, and 1 week after sc injection of 20 mg AOM/kg body weight. One week after the AOM treatment, groups of animals were transferred to high-fat diets containing 23.52% CO, 23.52% SO, 23.52% OO, and 23.52% CC, or 5.88% CO + 17.64% MCT; the remaining animals were continued on 5% fat diets. All animals were fed these diets until the termination of the experiment. Body weights and intakes of calories, protein, and micronutrients were comparable among the various dietary groups. The incidence of colon tumors was increased in rats fed diets containing high-CO and high-SO compared to those fed low-CO and low-SO diets, whereas the diets containing high OO, CC, or MCT had no promoting effect on colon tumor incidence. There was a significant increase in the excretion of fecal deoxycholic acid, lithocholic acid, and 12-ketolithocholic acid in animals fed the high-CO and high-SO diets and no difference in these secondary bile acids excretion in animals fed the high-OO and high-CC diets compared to those animals fed their respective 5% fat diets. This study thus indicates that not only the amount of dietary fat but also the fatty acid composition (type) of fat are important factors in the determination of the promoting effect in colon carcinogenesis.

Impacts of microalgae pre-treatments for improved anaerobic digestion: thermal treatment, thermal hydrolysis, ultrasound and enzymatic hydrolysis.

PubMed

Ometto, Francesco; Quiroga, Gerardo; Pšenička, Pavel; Whitton, Rachel; Jefferson, Bruce; Villa, Raffaella

2014-11-15

Anaerobic digestion (AD) of microalgae is primarily inhibited by the chemical composition of their cell walls containing biopolymers able to resist bacterial degradation. Adoption of pre-treatments such as thermal, thermal hydrolysis, ultrasound and enzymatic hydrolysis have the potential to remove these inhibitory compounds and enhance biogas yields by degrading the cell wall, and releasing the intracellular algogenic organic matter (AOM). This work investigated the effect of four pre-treatments on three microalgae species, and their impact on the quantity of soluble biomass released in the media and thus on the digestion process yields. The analysis of the composition of the soluble COD released and of the TEM images of the cells showed two main degradation actions associated with the processes: (1) cell wall damage with the release of intracellular AOM (thermal, thermal hydrolysis and ultrasound) and (2) degradation of the cell wall constituents with the release of intracellular AOM and the solubilisation of the cell wall biopolymers (enzymatic hydrolysis). As a result of this, enzymatic hydrolysis showed the greatest biogas yield increments (>270%) followed by thermal hydrolysis (60-100%) and ultrasounds (30-60%). Copyright © 2014 Elsevier Ltd. All rights reserved.

Relationship between oxidative damage and colon carcinogenesis in irradiated rats: influence of dietary countermeasures

NASA Astrophysics Data System (ADS)

Turner, Nancy; Sanders, Lisa; Wu, Guoyao; Davidson, Laurie; Ford, John; Braby, Leslie; Carroll, Raymond; Chapkin, Robert; Lupton, Joanne

Galactic cosmic radiation not only kills colon epithelial cells, it also generates a cellular environment that can lead to oxidative DNA damage. We previously demonstrated that a diet containing fish oil and pectin protects against initiation of colon cancer by enhancing apoptotic removal of cells with oxidative DNA adducts (8-OHdG), and that apoptosis was highly correlated with colon cancer suppression. We hypothesized this diet combination will mitigate the oxidative damage occurring from radiation and thus reduce colon cancer. The experiment tested the effect of radiation (± 1 Gy, 1 GeV/n Fe ions) on redox balance, apoptosis, and 8-OHdG levels at initiation and colon tumor incidence. Diets contained fish oil or corn oil, and cellulose or pectin (2x2 factorial design). Rats received the diets 3 wk before irradiation (half of the rats), followed by azoxymethane (AOM) injections 10 and 17 d later (all rats). Just prior to AOM injection, irradiated fish oil/pectin rats had a more reduced redox state in colonocytes (lower GSSG, P < 0.05; higher GSH/GSSG ratio), which was not observed in irradiated corn oil/cellulose rats. A shift to a more oxidative state (lower GSH and GSH/GSSG ratio, P < 0.05) occurred between 6 and 12 h after AOM in the fish oil/pectin irradiated rats. Changes in redox balance likely contributed to lower 8-OHdG levels in colonocytes from rats consuming the fish oil diets. Dietary pectin enhanced (P < 0.04) apoptosis induction 12 h after AOM injection in irradiated rats. Similar to the 8-OHdG results, colon tumor incidence was 42% higher (P < 0.05) in rats fed corn oil vs fish oil diets. In summary, fish oil/pectin diets created a more reduced colon environment in irradiated rats that was evident 10 d after irradiation. The ensuing oxidative shift in those rats after AOM injection may have enhanced apoptosis; effectively eliminating more DNA damaged cells. Thus, inclusion of fish oil and pectin in diets for long-duration space flights should help suppress the elevation in colon cancer risk caused by galactic cosmic radiation. Funded by NSBRI (NASA NCC 9-58), NIH CA90301, NIEHS P-30-ES09106.

The Effectiveness of Advance Organiser Model on Students' Academic Achievement in Learning Work and Energy

ERIC Educational Resources Information Center

Gidena, Asay; Gebeyehu, Desta

2017-01-01

The purpose of this study was to investigate the effectiveness of the advance organiser model (AOM) on students' academic achievement in learning work and energy. The design of the study was quasi-experimental pretest-posttest nonequivalent control groups. The total population of the study was 139 students of three sections in Endabaguna…

Nano-architectural Alterations in Mucus Layer Fecal Colonocytes in Field Carcinogenesis: Potential for Screening

PubMed Central

Roy, Hemant K.; Damania, Dhwanil P.; DelaCruz, Mart; Kunte, Dhananjay P.; Subramanian, Hariharan; Crawford, Susan E.; Tiwari, Ashish K.; Wali, Ramesh K.; Backman, Vadim

2013-01-01

Current fecal tests (occult blood, methylation, DNA mutations) target minute amounts of tumor products among a large amount of fecal material and thus have suboptimal performance. Our group has focused on exploiting field carcinogenesis as a modality to amplify the neoplastic signal. Specifically, we have demonstrated that endoscopically normal rectal brushings have striking nano-architectural alterations which are detectable utilizing a novel optical technique, partial wave spectroscopic microscopy (PWS). We therefore wished to translate this approach to a fecal assay. We examined mucus layer fecal colonocytes (MLFCs) at preneoplastic and neoplastic time-points (confirmed with rat colonoscopy) in the azoxymethane (AOM)-treated rat model and conducted PWS analysis to derive the nano-architectural parameter, disorder strength (Ld). We confirmed these results with studies in a genetic model (the Pirc rat). We demonstrated that MLFC appeared microscopically normal, consistent with field carcinogenesis. Ld was elevated at an early time point (5 weeks post-AOM injection, effect size = 0.40, p value = 0.024) and plateaued prior to adenoma formation (10 weeks post-AOM, effect size =0.66, p=0.001), with no dramatic increase once tumors developed. We replicated these data in the pre-neoplastic Pirc rat with an effect size in the MLFC that replicated the rectal brushings (increase versus age-matched controls of 62 versus 74%, respectively). We provide the first demonstration of a biophotonics approach to fecal assay. Furthermore, targeting the nano-architectural changes of field carcinogenesis rather than the detection of tumor products may provide a novel paradigm for colorectal cancer screening. PMID:23983085

Anaerobic Oxidation of Methane at a Marine Methane Seep in a Forearc Sediment Basin off Sumatra, Indian Ocean

PubMed Central

Siegert, Michael; Krüger, Martin; Teichert, Barbara; Wiedicke, Michael; Schippers, Axel

2011-01-01

A cold methane seep was discovered in a forearc sediment basin off the island Sumatra, exhibiting a methane-seep adapted microbial community. A defined seep center of activity, like in mud volcanoes, was not discovered. The seep area was rather characterized by a patchy distribution of active spots. The relevance of anaerobic oxidation of methane (AOM) was reflected by 13C-depleted isotopic signatures of dissolved inorganic carbon. The anaerobic conversion of methane to CO2 was confirmed in a 13C-labeling experiment. Methane fueled a vital microbial community with cell numbers of up to 4 × 109 cells cm−3 sediment. The microbial community was analyzed by total cell counting, catalyzed reporter deposition–fluorescence in situ hybridization (CARD–FISH), quantitative real-time PCR (qPCR), and denaturing gradient gel electrophoresis (DGGE). CARD–FISH cell counts and qPCR measurements showed the presence of Bacteria and Archaea, but only small numbers of Eukarya. The archaeal community comprised largely members of ANME-1 and ANME-2. Furthermore, members of the Crenarchaeota were frequently detected in the DGGE analysis. Three major bacterial phylogenetic groups (δ-Proteobacteria, candidate division OP9, and Anaerolineaceae) were abundant across the study area. Several of these sequences were closely related to the genus Desulfococcus of the family Desulfobacteraceae, which is in good agreement with previously described AOM sites. In conclusion, the majority of the microbial community at the seep consisted of AOM-related microorganisms, while the relevance of higher hydrocarbons as microbial substrates was negligible. PMID:22207865

Environmental controls on sulfur isotopic composition of sulfide minerals in seep carbonates from the South China Sea

NASA Astrophysics Data System (ADS)

Gong, S.; Li, N.; Liang, Q.; Chen, D.; Feng, D.

2017-12-01

Authigenic carbonates and pyrite associated with sulfate-driven anaerobic oxidation of methane (AOM) at methane seeps provide archives to explore the biogeochemical processes involved and seepage dynamics over time. The wide range and extremely high δ34Spy value of authigenic sulfide has been used to trace the AOM-related processes. However, the detail mechanism for this is unknown. We proposed the δ34Spy characteristics result from high sulfate reduction rate and its competition with sulfate supply rate. To test this hypothesis, we investigated Mo content, Sr/Ca and Mg/Ca ratios, pyrite content, and its sulfur isotopic compositions in methane-derived carbonates from Site F and Haima in northern South China Sea. Calcite and aragonite were distinguished through the Sr/Ca and Mg/Ca ratios. The data show that aragonites are always associated with relatively low δ34Spy values compared to calcites. The Mo content and pyrite have good linear correlations in both aragonites and calcites, and aragonites have more positive slope than calcites. This indicates that there is more Mo available from seawater during the aragonite precipitation. The data suggest that the low δ34Spy values are formed at higher supply rate of sulfate under relatively open system, and high δ34Spy values result from a deep sulfate methane transition zone where dissolve sulfate near to complete exhausted via AOM. The combination of a detailed elemental study of authigenic carbonate with sulfur isotopes of sulfide minerals in carbonates are promising tools for reconstructing the dynamics of seep intensities in modern and, potentially, geological record.

Anaerobic Oxidation of Methane at a Marine Methane Seep in a Forearc Sediment Basin off Sumatra, Indian Ocean.

PubMed

Siegert, Michael; Krüger, Martin; Teichert, Barbara; Wiedicke, Michael; Schippers, Axel

2011-01-01

A cold methane seep was discovered in a forearc sediment basin off the island Sumatra, exhibiting a methane-seep adapted microbial community. A defined seep center of activity, like in mud volcanoes, was not discovered. The seep area was rather characterized by a patchy distribution of active spots. The relevance of anaerobic oxidation of methane (AOM) was reflected by (13)C-depleted isotopic signatures of dissolved inorganic carbon. The anaerobic conversion of methane to CO(2) was confirmed in a (13)C-labeling experiment. Methane fueled a vital microbial community with cell numbers of up to 4 × 10(9) cells cm(-3) sediment. The microbial community was analyzed by total cell counting, catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), quantitative real-time PCR (qPCR), and denaturing gradient gel electrophoresis (DGGE). CARD-FISH cell counts and qPCR measurements showed the presence of Bacteria and Archaea, but only small numbers of Eukarya. The archaeal community comprised largely members of ANME-1 and ANME-2. Furthermore, members of the Crenarchaeota were frequently detected in the DGGE analysis. Three major bacterial phylogenetic groups (δ-Proteobacteria, candidate division OP9, and Anaerolineaceae) were abundant across the study area. Several of these sequences were closely related to the genus Desulfococcus of the family Desulfobacteraceae, which is in good agreement with previously described AOM sites. In conclusion, the majority of the microbial community at the seep consisted of AOM-related microorganisms, while the relevance of higher hydrocarbons as microbial substrates was negligible.

Once or twice daily versus three times daily amoxicillin with or without clavulanate for the treatment of acute otitis media.

PubMed

Thanaviratananich, Sanguansak; Laopaiboon, Malinee; Vatanasapt, Patravoot

2013-12-13

Acute otitis media (AOM) is a common problem in children, for which amoxicillin, with or without clavulanate, is frequently prescribed as a treatment of choice. The conventional recommendation is either three or four daily doses. However, nowadays it is frequently prescribed as once or twice daily doses. If once or twice daily amoxicillin, with or without clavulanate, is as effective for acute otitis media as three or four times a day, it may be more convenient to give the medication once or twice a day to children and hence improve compliance. To compare the effectiveness of one or two daily doses with three or four daily doses of amoxicillin, with or without clavulanate, for the treatment of AOM in children; and to compare complication rates and adverse reactions. We searched CENTRAL 2013, Issue 2, MEDLINE (January 1950 to March week 1, 2013), EMBASE (1974 to March 2013) and the Science Citation Index (2001 to March 2013). We included randomised controlled trials (RCTs) of children aged 12 years or younger with AOM, diagnosed by acute ear pain (otalgia) and inflamed ear drum (confirmed by positive tympanocentesis or tympanogram of type B or C). Two review authors independently extracted data on treatment outcomes from individual trials and assessed trial quality based on selection bias, performance bias and detection bias, attrition bias, reporting bias and other biases. We defined the quality grading as low risk of bias, high risk of bias or unclear risk of bias. We summarised the results as risk ratio (RR) with 95% confidence intervals (CI). We included five studies with 1601 children in the review. Pooled analysis demonstrated that the following outcomes were comparable between the two groups: clinical cure at the end of therapy (RR 1.03, 95% CI 0.99 to 1.07); during therapy (RR 1.06, 95% CI 0.85 to 1.33) and at follow-up (RR 1.02, 95% CI 0.95 to 1.09); recurrent AOM (RR 1.21, 95% CI 0.52 to 2.81); compliance rate (RR 1.04, 95% CI 0.98 to 1.10) and overall adverse events (RR 0.92, 95% CI 0.52 to 1.63). When we performed subgroup analysis separately for trials with amoxicillin only and amoxicillin/clavulanate only, it showed that all important outcomes were comparable between once or twice daily groups and the three times daily group. The risk of bias amongst the five included studies was as follows: for random sequence generation we graded two studies as low and three unclear risk of bias; for allocation concealment all studies were at unclear risk of bias; for blinding (performance and detection bias) we graded four as high and one as unclear risk of bias; for incomplete outcome data (attrition bias) we graded two low, two high and one as unclear risk of bias; for reporting bias four were at low and one at high risk; and for 'other' bias four were at low and one at unclear risk of bias. This review showed that the results of using once or twice daily doses of amoxicillin, with or without clavulanate, were comparable with three doses for the treatment of AOM.

New insights into the transport processes controlling the sulfate-methane-transition-zone near methane vents.

PubMed

Sultan, Nabil; Garziglia, Sébastien; Ruffine, Livio

2016-05-27

Over the past years, several studies have raised concerns about the possible interactions between methane hydrate decomposition and external change. To carry out such an investigation, it is essential to characterize the baseline dynamics of gas hydrate systems related to natural geological and sedimentary processes. This is usually treated through the analysis of sulfate-reduction coupled to anaerobic oxidation of methane (AOM). Here, we model sulfate reduction coupled with AOM as a two-dimensional (2D) problem including, advective and diffusive transport. This is applied to a case study from a deep-water site off Nigeria's coast where lateral methane advection through turbidite layers was suspected. We show by analyzing the acquired data in combination with computational modeling that a two-dimensional approach is able to accurately describe the recent past dynamics of such a complex natural system. Our results show that the sulfate-methane-transition-zone (SMTZ) is not a vertical barrier for dissolved sulfate and methane. We also show that such a modeling is able to assess short timescale variations in the order of decades to centuries.

Suppression by nimesulide of bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in Wistar rats.

PubMed

Iishi, Hiroyasu; Tatsuta, Masaharu; Baba, Miyako; Yano, Hiroyuki; Higashino, Koji; Mukai, Mutsuko; Akedo, Hitoshi

2003-01-01

The effects of the cyclooxygenase (COX)-2 inhibitor nimesulide on bombesin-enhanced peritoneal metastasis of azoxymethane (AOM)-induced intestinal adenocarcinomas were investigated in male Wistar rats. From the beginning of the study, the rats were given 10 weekly s.c. injections of AOM (7.4 mg/kg body weight) and s.c. injections of bombesin (40 microg/kg body weight) every other day. From week 16, the rats were given chow pellets containing 200 ppm or 400 ppm nimesulide ad libitum until termination of the study at week 45. Nimesulide at the higher dose significantly decreased the incidence of bombesin-enhanced metastasis to the peritoneum at week 45, although its administration had little or no effect on the location, histologic type, depth of involvement or infiltrating growth patterns of the tumors. Nimesulide also significantly decreased the incidence of bombesin-enhanced lymphatic vessel invasion by adenocarcinomas. Finally, it also inhibited bombesin-induced matrix metalloproteinase (MMP)-9 and pro-MMP-9 inductions. Our findings indicate that nimesulide may inhibit cancer metastasis through inhibition of pro-MMP-9 and MMP-9 inductions.

Double Q-switch Ho:Sc2SiO5 laser by acousto-optic modulator combined with Cr2+:ZnSe saturable absorber

NASA Astrophysics Data System (ADS)

Yang, Xiao-tao; Zhang, Peng; Xie, Wen-qiang; Li, Lin-jun

2018-01-01

A double Q-switch (DQS) Ho:Sc2SiO5 laser modulated by a acousto-optic modulators (AOM) combined with a Cr2+:ZnSe saturable absorber (SA) was reported for the first time. The actively Q-switch (AQS) and passively Q-switch (PQS) were also studied. For the DQS mode, a maximum average output power of 2.49 W under the incident pump power of 12.5 W was obtained, corresponding to a slope efficiency of 24%. The characteristics of the DQS Ho:SSO laser versus different repetition frequencies (RF) of the AOM were researched. The maximum single-pulse energy of the DQS Ho:SSO laser was calculated to 1.98 mJ. The maximum peak power of the DQS Ho:SSO laser was 49.5 kW. The output beam quality factor M2 of DQS Ho:SSO laser was measured to be 1.15 with the highest peak power by knife-edge method at different positions.

Origin of lipid biomarkers in mud volcanoes from the Alboran Sea, western Mediterranean

NASA Astrophysics Data System (ADS)

López-Rodríguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruíz, F.; Comas, M.; Sinninghe Damsté, J. S.

2013-11-01

Mud volcanoes (MVs) are the most prominent indicators of active methane/hydrocarbon venting at the seafloor on both passive and active continental margins. Their occurrence in the Western Mediterranean is patent at the West Alboran Basin, where numerous MVs develop overlaying a major sedimentary depocenter containing overpressured shales. Although some of these MVs have been studied, the detailed biogeochemistry of expelled mud so far has not been examined in detail. This work provides the first results on the composition and origin of organic matter, Anaerobic Oxidation of Methane (AOM) processes and general characteristics on MV dynamics using lipid biomarkers as the main tool. Lipid biomarker analysis was performed on MV expelled material (mud breccias) and interbedded hemipelagic sediments from Perejil, Kalinin and Schneider's Heart MVs located in the northwest margin of the Alboran Sea. The n-alkane-distributions and n-alkane-derived indices (CPI and ACL), in combination with the epimerization degree of hopanes (22S/(22S + 22R)) indicate that all studied mud breccia have a similar biomarker composition consisting of mainly thermally immature organic matter with an admixture of petroleum-derived compounds. This concordant composition indicates that common source strata must feed all three studied MVs. The past or present AOM activity was established using lipid biomarkers specific for anaerobic methanotropic archaea (irregular isoprenoids and DGDs) and the depleted carbon isotope composition (δ13C) of crocetane/phytane. The presence of these lipid biomarkers, together with the low amounts of detected GDGTs, is consistent with the dominance of anaerobic methanotrophs of the ANME-2 over ANME-1, at least in mud breccia from Perejil MVs. In contrast, the scarce presence or lack of these AOM-related lipid biomarkers in sediments from Kalinin and Schneider's Heart MVs, suggest no recent active methane seepage has occurred at these sites. Moreover, the observed methane concentrations support the current activity of Perejil MV, and the very low methane seepage activity in Kalinin and Schneider's Heart MVs.

Etiology of Acute Otitis Media in Children Less Than 5 Years of Age

PubMed Central

Van Dyke, Melissa K.; Pirçon, Jean-Yves; Cohen, Robert; Madhi, Shabir A.; Rosenblüt, Andrés; Macias Parra, Mercedes; Al-Mazrou, Khalid; Grevers, Gerhard; Lopez, Pio; Naranjo, Laura; Pumarola, Felix; Sonsuwan, Nuntigar

2017-01-01

Background: Acute otitis media (AOM) is an important cause of childhood morbidity and antibiotic prescriptions. However, the relative importance of the well-known otopathogens, Streptococcus pneumoniae (Spn) and Haemophilus influenzae (Hflu), remains unclear because of a limited number of tympanocentesis-based studies that vary significantly in populations sampled, case definitions and heptavalent pneumococcal conjugate vaccine use. Methods: We conducted a pooled analysis of results from 10 AOM etiology studies of similar design, the protocols of which were derived from a common protocol and conducted in children 3 months to 5 years of age in different countries. Generalized estimating equations were used to account for within-study correlations. Results: The majority, 55.5% (95% confidence interval: 47.0%–65.7%) of 1124 AOM episodes, were bacterial pathogen positive: 29.1% (24.8%–34.1%) yielded Hflu and 23.6% (19.0%–29.2%) Spn. Proportions of Hflu and Spn were higher and lower, respectively, in heptavalent pneumococcal conjugate vaccine–vaccinated children. Hflu and Spn were each isolated from 20% to 35% of children in every 1-year age range. Hflu was less likely to be isolated from first (vs. subsequent) episodes [relative risk (RR): 0.71 (0.60–0.84)]. Spn was more often isolated from sporadic (vs. recurrent) cases [RR: 0.76 (0.61–0.97)]; the opposite was true for Hflu [RR: 1.4 (1.00–1.96)]. Spn cases were more likely to present with severe (vs. mild) symptoms [RR: 1.42 (1.01–2.01)] and Hflu cases with severe tympanic membrane inflammation [RR: 1.35 (1.06–1.71)]. Conclusions: Spn and Hflu remain the leading otopathogens in all populations examined. While associated with overlapping symptoms and severity, they exhibit some differences in their likelihood to cause disease in specific subpopulations. PMID:27918383

Anaerobic Oxidation of Methane in a French meromictic lake (Lake Pavin): Who is responsible?

NASA Astrophysics Data System (ADS)

Grossi, V.; Attard, E.; Birgel, D.; Schaeffer, P.; Jézéquel, D.; Lehours, A.

2012-12-01

Methane is an important greenhouse gas and its biogeochemical cycle is of primary significance to the global carbon cycle. The Anaerobic Oxidation of Methane (AOM) has been estimated to be responsible for >90% of methane consumption. This biogeochemical process has been increasingly documented during the last two decades but the underlying microbial processes and their key agents remain incompletely understood. Freshwater lakes account for 2-10% of the total emissions of methane and are therefore an important part of the global methane cycle. Lake Pavin is a French meromictic crater lake with unusual hydrological characteristics: its morphology (depth >92m, mean diameter 750m) induce that waters below 60m are never mixed with overlying waters and remain permanently anoxic. The deep anoxic waters of Lake Pavin contain high concentrations (i.e. 4 mM) of methane but, contrary to other aquatic systems, almost no methane escapes from the lake. Previous biogeochemical and modeling studies suggest that methane is preferentially consumed within the oxic-anoxic transition zone (ca. 55-60 m depth) but that ca. 30% of methane oxidation occurs in the anoxic part of the lake. Phylogenetic (16S rRNA) analyses showed that ANME generally involved in AOM (ANME-1, -2 and -3) are not present in Lake Pavin. Other archaeal groups that do not have any cultured representatives so far appear well represented in the anoxic parts of the lake but their implication in AOM is not demonstrated. The analysis of lipid biomarkers using GC-MS and LC-MS revealed the presence of a low diversity of archaeal-specific biomarkers in the superficial sediments and in the anoxic waters of the lake. Archaeol and caldarcheaol (GDGT-0) are the two main archaeal core lipids detected; other biomarkers generally present in ANME such as pentamethylicosane or hydroxyarchaeol are not present. However, the stable carbon isotopic composition of archaeol (δ13C = -18‰) and of the biphytane chain of GDGT-0 (δ13C = -31‰) released following the chemical degradation of ether bonds with HI, argue against an origin from archaea involved in AOM. Intriguingly, the only 13C-depleted (-66‰<δ13C<-53‰) lipid biomarkers detected in the superficial sediments and in the anoxic waters of Lake Pavin are bacterial hopanoids (diploptene, diplopterol, C32 homohopanols and homohopanoic acid). Such 13C-depleted hopanoids are generally thought to be specific of aerobic methanotrophic bacteria but the recent discovery of hopanoids in cultures of strictly anaerobic bacteria allows envisaging AOM in Lake Pavin as a bacterially-driven process. The analysis of lipid biomarkers from the different redox zones of the water column (oxic, transition oxic-anoxic, fully anoxic) is currently being investigated and should help assessing the unconventional anaerobic methane consumers of Lake Pavin.

Etiology and antimicrobial susceptibility of middle ear fluid pathogens in Costa Rican children with otitis media before and after the introduction of the 7-valent pneumococcal conjugate vaccine in the National Immunization Program: acute otitis media microbiology in Costa Rican children.

PubMed

Abdelnour, Arturo; Arguedas, Adriano; Dagan, Ron; Soley, Carolina; Porat, Nurith; Castrejon, Maria Mercedes; Ortega-Barria, Eduardo; Colindres, Romulo; Pirçon, Jean-Yves; DeAntonio, Rodrigo; Van Dyke, Melissa K

2015-01-01

Acute otitis media (AOM) microbiology was evaluated in children after 7-valent pneumococcal conjugate vaccine (PCV7) introduction in Costa Rica (private sector, 2004; National Immunization Program, 2009). This was a combined prospective and retrospective study conducted in a routine clinical setting in San José, Costa Rica. In the prospective part of the study, which was conducted post-PCV7 introduction (2010-2012), standard bacteriological procedures were used to evaluate the etiology and serotype distribution of middle ear fluid samples collected by tympanocentesis or otorrhea from children aged 3-59 months diagnosed with AOM. E-tests were used to evaluate antimicrobial susceptibility in culture-positive samples. Retrospective data recorded between 1999 and 2004 were used for comparison of bacterial etiology and serotype distribution before and after PCV7 introduction. Statistical significance was evaluated in bivariate analyses at the P-value < 0.05 level (without multiplicity correction). Post-PCV7 introduction, Haemophilus influenzae was detected in 118/456 and Streptococcus pneumoniae in 87/456 AOM episodes. Most H. influenzae isolates (113/118) were non-typeable. H. influenzae was more (27.4% vs 20.8%) and S. pneumoniae less (17.1% vs 25.5%) frequently observed in vaccinated (≥ 2 PCV7 doses or ≥ 1 PCV7 dose at >1 year of age) versus unvaccinated children. S. pneumoniae non-susceptibility rates were 1.1%, 34.5%, 31.7%, and 50.6% for penicillin, erythromycin, azithromycin, and trimethoprim/sulfamethoxazole (TMP-SMX), respectively. H. influenzae non-susceptibility rate was 66.9% for TMP-SMX. Between pre- and post-PCV7 introduction, H. influenzae became more (20.5% vs 25.9%; P-value < 0.001) and S. pneumoniae less (27.7% vs 19.1%; P-value = 0.002) prevalent, and PCV7 serotype proportions decreased among pneumococcal isolates (65.8% vs 43.7%; P-value = 0.0005). Frequently identified pneumococcal serotypes were 19F (34.2%), 3 (9.7%), 6B (9.7%), and 14 (9.7%) pre-PCV7 introduction, and 19F (27.6%), 14 (8.0%), and 35B (8.0%) post-PCV7 introduction. Following PCV7 introduction, a change in the distribution of AOM episodes caused by H. influenzae and pneumococcal serotypes included in PCV7 was observed in Costa Rican children. Pneumococcal vaccines impact should be further evaluated following broader vaccination coverage.

Chemoprevention of azoxymethane-induced colon cancer by ascorbylpalmitate, carbenoxolone, dimethylfumarate and p-methoxyphenol in male F344 rats.

PubMed

Rao, C V; Rivenson, A; Kelloff, G J; Reddy, B S

1995-01-01

The chemopreventive effect of 40 and 80% maximum tolerated dose (MTD) levels of ascorbylpalmitate (AP), carbenoxolone (CBX), dimethylfumarate (DMF) and p-methoxyphenol (p-MP) administrated in the diet before and during initiation and postinitiation phases of azoxymethane (AOM)-induced colon carcinogenesis was studied in male F344 rats. The MTD levels of AP, CBX, DMF and p-MP were determined in male F344 rats and found to be 5000 1500, 1000 and 1000 ppm, respectively, in modified AIN-76A diet. Based on these MTD values, 40 and 80% MTD levels of each agent was tested for their efficacy in color carcinogenesis. At 5 weeks of age, groups of animals were fed the control (modified AIN-76A diet or diets containing 40 and 80% MTD levels of each AP, CBX, DMF and p-MP. At 7 weeks of age, all animals, except those in the vehicle (normal saline)-treated groups, were given two weekly s.c. injections of AOM at a dose rate of 15 mg/kg body weight/week. All groups were continued on their respective dietary regimen until the termination of the experiment 52 weeks after the carcinogen treatment. Colonic tumors were evaluated histopathologically. The results indicate that dietary administration of 40% MTD of AP significantly inhibited multiplicities (tumor/animal) of noninvasive and total (invasive plus noninvasive) adenocarcinoma of the colon (P < 0.05) and 80% MTD of AP significantly inhibited the incidence (% animals with tumors) and the multiplicities of invasive and total adenocarcinomas of the colon (P < 0.01). Dietary CBX at 40 and 80% MTD levels suppressed the incidence and multiplicities of invasive and total adenocarcinomas (P < 0.05 to 0.001) whereas 40 and 80% MTD of DMF and p-MP had significantly inhibited invasive adenocarcinoma incidence and multiplicity (P < 0.05 to 0.001). However, DMF and p-MP had no significant effect on noninvasive and total adenocarcinoma incidence and multiplicity (P > 0.05). These results suggest that AP and CBX possess potential chemopreventive properties against colon cancer.

Predominant Bacteria Detected from the Middle Ear Fluid of Children Experiencing Otitis Media: A Systematic Review.

PubMed

Ngo, Chinh C; Massa, Helen M; Thornton, Ruth B; Cripps, Allan W

2016-01-01

Otitis media (OM) is amongst the most common childhood diseases and is associated with multiple microbial pathogens within the middle ear. Global and temporal monitoring of predominant bacterial pathogens is important to inform new treatment strategies, vaccine development and to monitor the impact of vaccine implementation to improve progress toward global OM prevention. A systematic review of published reports of microbiology of acute otitis media (AOM) and otitis media with effusion (OME) from January, 1970 to August 2014, was performed using PubMed databases. This review confirmed that Streptococcus pneumoniae and Haemophilus influenzae, remain the predominant bacterial pathogens, with S. pneumoniae the predominant bacterium in the majority reports from AOM patients. In contrast, H. influenzae was the predominant bacterium for patients experiencing chronic OME, recurrent AOM and AOM with treatment failure. This result was consistent, even where improved detection sensitivity from the use of polymerase chain reaction (PCR) rather than bacterial culture was conducted. On average, PCR analyses increased the frequency of detection of S. pneumoniae and H. influenzae 3.2 fold compared to culture, whilst Moraxella catarrhalis was 4.5 times more frequently identified by PCR. Molecular methods can also improve monitoring of regional changes in the serotypes and identification frequency of S. pneumoniae and H. influenzae over time or after vaccine implementation, such as after introduction of the 7-valent pneumococcal conjugate vaccine. Globally, S. pneumoniae and H. influenzae remain the predominant otopathogens associated with OM as identified through bacterial culture; however, molecular methods continue to improve the frequency and accuracy of detection of individual serotypes. Ongoing monitoring with appropriate detection methods for OM pathogens can support development of improved vaccines to provide protection from the complex combination of otopathogens within the middle ear, ultimately aiming to reduce the risk of chronic and recurrent OM in vulnerable populations.

Predominant Bacteria Detected from the Middle Ear Fluid of Children Experiencing Otitis Media: A Systematic Review

PubMed Central

Ngo, Chinh C.; Massa, Helen M.; Thornton, Ruth B.; Cripps, Allan W.

2016-01-01

Background Otitis media (OM) is amongst the most common childhood diseases and is associated with multiple microbial pathogens within the middle ear. Global and temporal monitoring of predominant bacterial pathogens is important to inform new treatment strategies, vaccine development and to monitor the impact of vaccine implementation to improve progress toward global OM prevention. Methods A systematic review of published reports of microbiology of acute otitis media (AOM) and otitis media with effusion (OME) from January, 1970 to August 2014, was performed using PubMed databases. Results This review confirmed that Streptococcus pneumoniae and Haemophilus influenzae, remain the predominant bacterial pathogens, with S. pneumoniae the predominant bacterium in the majority reports from AOM patients. In contrast, H. influenzae was the predominant bacterium for patients experiencing chronic OME, recurrent AOM and AOM with treatment failure. This result was consistent, even where improved detection sensitivity from the use of polymerase chain reaction (PCR) rather than bacterial culture was conducted. On average, PCR analyses increased the frequency of detection of S. pneumoniae and H. influenzae 3.2 fold compared to culture, whilst Moraxella catarrhalis was 4.5 times more frequently identified by PCR. Molecular methods can also improve monitoring of regional changes in the serotypes and identification frequency of S. pneumoniae and H. influenzae over time or after vaccine implementation, such as after introduction of the 7-valent pneumococcal conjugate vaccine. Conclusions Globally, S. pneumoniae and H. influenzae remain the predominant otopathogens associated with OM as identified through bacterial culture; however, molecular methods continue to improve the frequency and accuracy of detection of individual serotypes. Ongoing monitoring with appropriate detection methods for OM pathogens can support development of improved vaccines to provide protection from the complex combination of otopathogens within the middle ear, ultimately aiming to reduce the risk of chronic and recurrent OM in vulnerable populations. PMID:26953891

Curcumin ameliorates the tumor-enhancing effects of a high-protein diet in an azoxymethane-induced mouse model of colon carcinogenesis.

PubMed

Byun, So-Young; Kim, Dan-Bi; Kim, Eunjung

2015-08-01

An increasing number of reports suggest that a high-protein diet (HPD) is associated with an increased risk for colorectal cancer (CRC). One of the proposed mechanisms is that an HPD increases the delivery of protein to the colon and generates various toxic metabolites that contribute to colon carcinogenesis. Curcumin was shown to exert significant preventive properties against CRC. We therefore hypothesized that curcumin can reverse the tumor-enhancing effects of an HPD. This study examined the effects of curcumin on the development of azoxymethane (AOM)-induced colorectal tumors in HPD-fed mice. A total of 30 female Balb/c mice were randomly divided into 3 groups: those fed a normal diet (20% casein), those fed an HPD (HPD; 50% casein), and those fed an HPD supplemented with curcumin (HPDC; 0.02% curcumin). The mice were subjected to an AOM-dextran sodium sulfate colon carcinogenesis protocol. Mice in the HPDC group exhibited a significant (40%) reduction in colorectal tumor multiplicity when compared with those in the HPD group. The expression of colonic inflammatory proteins (cyclooxygenase-2 and inducible nitric oxide synthase), the levels of plasma inflammatory markers (nitric oxide and tumor necrosis factor-α), fecal ammonia, short- and branched-chain fatty acid levels, and the rate of colonocyte proliferation were significantly lower in the HPDC than the HPD group. In conclusion, curcumin inhibited the development of colorectal tumors in an AOM-induced mouse model of colon carcinogenesis by attenuating colonic inflammation, proliferation, and toxic metabolite production. Curcumin might be useful in the chemoprevention of CRC in individuals consuming an HPD. Copyright © 2015 Elsevier Inc. All rights reserved.

Microbial mats in the Black Sea that anaerobically oxidise methane

NASA Astrophysics Data System (ADS)

Nauhaus, K.; Knittel, K.; Krüger, M.; Boetius, A.; Michaelis, W.; Widdel, F.

2003-04-01

Reef-forming microbial mats were recovered from methane seeps in anoxic waters of the northwestern Black Sea (BS) shelf. The microbial mats consist mainly of archaea (ANME-1 cluster) and sulfate-reducing bacteria (Desulfosarcina/Desulfococcus group). Laboratory incubations with homogenized subsamples of the mats revealed their ability for the anaerobic oxidation of methane (AOM). The phylogentic relationship of the sulfate reducing partner is the same as in the AOM consortia studied in sediment samples from a methane hydrate area (Hydrate Ridge (HR), Oregon, USA (1,2)). The archaeal partner however belongs to a different cluster than in the HR samples (ANME-2). Methane oxidation is coupled to sulfate reduction in a 1:1 stoichiometry. Elevated methane partial pressures (0.1 to 1.1 MPa) increased the sulfate reduction rates in the Black Sea samples only two-fold in contrast to 5-fold in HR samples. The optimal temperature for the BS samples is between 10 and 25^oC. In both samples AOM was not taking place if typical inhibitors for sulfate-reduction or methanogenesis were added, thus indicating a syntrophic relationship between the partner organisms. The intermediate that is exchanged between the methane oxidizing archaea and the sulfate-reducing bacterium is still unknown. Additions of the possible intermediates (Acetate, Formate, Hydrogen) did not result in higher sulfate reduction rates in the absence of methane. (1) Boetius, A. et al. (2000) A marine microbial consortium apparently mediating anaerobic oxidation of methane. Nature. 407: 623--626 (2) Nauhaus, K., Boetius, A., Krüger, M., Widdel, F. (2002) In vitro demonstration of anaerobic oxidation of methane coupled to sulphate reduction in sediment from a marine gas hydrate area. Environ. Microbiol. 4 (5): 296--305

Biogeochemical cycles at the sulfate-methane transition zone (SMTZ) and geochemical characteristics of the pore fluids offshore southwestern Taiwan

NASA Astrophysics Data System (ADS)

Hu, Ching-Yi; Frank Yang, Tsanyao; Burr, George S.; Chuang, Pei-Chuan; Chen, Hsuan-Wen; Walia, Monika; Chen, Nai-Chen; Huang, Yu-Chun; Lin, Saulwood; Wang, Yunshuen; Chung, San-Hsiung; Huang, Chin-Da; Chen, Cheng-Hong

2017-11-01

In this study, we used pore water dissolved inorganic carbon (DIC), SO42-, Ca2+ and Mg2+ gradients at the sulfate-methane transition zone (SMTZ) to estimate biogeochemical fluxes for cored sediments collected offshore SW Taiwan. Net DIC flux changes (ΔDIC-Prod) were applied to determine the proportion of sulfate consumption by organic matter oxidation (heterotrophic sulfate reduction) and anaerobic oxidation of methane (AOM), and to determine reliable CH4 fluxes at the SMTZ. Our results show that SO42- profiles are mainly controlled by AOM rather than heterotrophic sulfate reduction. Refinement of CH4 flux estimates enhance our understanding of methane abundance from deep carbon reservoirs to the SMTZ. Concentrations of chloride (Cl-), bromide (Br-) and iodide (I-) dissolved in pore water were used to identify potential sources that control fluid compositions and the behavior of dissolved ions. Constant Cl- concentrations throughout ∼30 m sediment suggest no influence of gas hydrates for the compositions within the core. Bromide (Br-) and Iodine (I-) concentrations increase with sediment depth. The I-/Br- ratio appears to reflect organic matter degradation. SO42- concentrations decrease with sediment depth at a constant rate, and sediment depth profiles of Br- and I- concentrations suggests diffusion as the main transport mechanism. Therefore diffusive flux calculations are reasonable. Coring sites with high CH4 fluxes are more common in the accretionary wedge, amongst thrust faults and fractures, than in the passive continental margin offshore southwestern Taiwan. AOM reactions are a major sink for CH4 passing upward through the SMTZ and prevent high methane fluxes in the water column and to the atmosphere.

Visualizing in situ translational activity for identifying and sorting slow-growing archaeal−bacterial consortia

PubMed Central

Hatzenpichler, Roland; Connon, Stephanie A.; Goudeau, Danielle; Malmstrom, Rex R.; Woyke, Tanja; Orphan, Victoria J.

2016-01-01

To understand the biogeochemical roles of microorganisms in the environment, it is important to determine when and under which conditions they are metabolically active. Bioorthogonal noncanonical amino acid tagging (BONCAT) can reveal active cells by tracking the incorporation of synthetic amino acids into newly synthesized proteins. The phylogenetic identity of translationally active cells can be determined by combining BONCAT with rRNA-targeted fluorescence in situ hybridization (BONCAT-FISH). In theory, BONCAT-labeled cells could be isolated with fluorescence-activated cell sorting (BONCAT-FACS) for subsequent genetic analyses. Here, in the first application, to our knowledge, of BONCAT-FISH and BONCAT-FACS within an environmental context, we probe the translational activity of microbial consortia catalyzing the anaerobic oxidation of methane (AOM), a dominant sink of methane in the ocean. These consortia, which typically are composed of anaerobic methane-oxidizing archaea (ANME) and sulfate-reducing bacteria, have been difficult to study due to their slow in situ growth rates, and fundamental questions remain about their ecology and diversity of interactions occurring between ANME and associated partners. Our activity-correlated analyses of >16,400 microbial aggregates provide the first evidence, to our knowledge, that AOM consortia affiliated with all five major ANME clades are concurrently active under controlled conditions. Surprisingly, sorting of individual BONCAT-labeled consortia followed by whole-genome amplification and 16S rRNA gene sequencing revealed previously unrecognized interactions of ANME with members of the poorly understood phylum Verrucomicrobia. This finding, together with our observation that ANME-associated Verrucomicrobia are found in a variety of geographically distinct methane seep environments, suggests a broader range of symbiotic relationships within AOM consortia than previously thought. PMID:27357680

Supplementation with branched-chain amino acids inhibits azoxymethane-induced colonic preneoplastic lesions in male C57BL/KsJ-db/db mice.

PubMed

Shimizu, Masahito; Shirakami, Yohei; Iwasa, Junpei; Shiraki, Makoto; Yasuda, Yoichi; Hata, Kazuya; Hirose, Yoshinobu; Tsurumi, Hisashi; Tanaka, Takuji; Moriwaki, Hisataka

2009-05-01

Obesity and related metabolic abnormalities, including insulin resistance and activation of the insulin-like growth factor (IGF)/IGF-I receptor (IGF-IR) axis, are risk factors for colon cancer. Supplementation with branched-chain amino acids (BCAA) reduces the risk of liver cancer in cirrhotic patients who are obese, and this has been associated with an improvement of insulin resistance. The present study examined the effects of BCAA on the development of azoxymethane (AOM)-initiated colonic premalignant lesions in C57BL/KsJ-db/db (db/db) mice that were obese and had hyperinsulinemia. Male db/db mice were given 4 weekly s.c. injections of AOM (15 mg/kg of body weight) and then they were fed a diet containing 3.0% BCAA or casein, a nitrogenc content-matched control diet, for 7 weeks. Feeding with BCAA caused a significant reduction in the number of total aberrant crypt foci and beta-catenin accumulated crypts, both of which are premalignant lesions of the colon, compared with the control diet-fed groups. BCAA supplementation caused a marked decrease in the expression of IGF-IR, the phosphorylated form of IGF-IR, phosphorylated glycogen synthase kinase 3beta, phosphorylated Akt, and cyclooxygenase-2 proteins on the colonic mucosa of AOM-treated mice. The serum levels of insulin, IGF-I, IGF-II, triglyceride, total cholesterol, and leptin were also decreased by supplementation with BCAA. BCAA supplementation in diet improves insulin resistance and inhibits the activation of the IGF/IGF-IR axis, thereby preventing the development of colonic premalignancies in an obesity-related colon cancer model that was also associated with hyperlipidemia and hyperinsulinemia. BCAA, therefore, may be a useful chemoprevention modality for colon cancer in obese people.

Celastrol Ameliorates Ulcerative Colitis-Related Colorectal Cancer in Mice via Suppressing Inflammatory Responses and Epithelial-Mesenchymal Transition

PubMed Central

Lin, Lianjie; Sun, Yan; Wang, Dongxu; Zheng, Shihang; Zhang, Jing; Zheng, Changqing

2016-01-01

Celastrol, also named as tripterine, is a pharmacologically active ingredient extracted from the root of traditional Chinese herb Tripterygium wilfordii Hook F with potent anti-inflammatory and anti-tumor activities. In the present study, we investigated the effects of celastrol on ulcerative colitis-related colorectal cancer (UC-CRC) as well as CRC in vivo and in vitro and explored its underlying mechanisms. UC-CRC model was induced in C57BL/6 mice by administration of azoxymethane (AOM) and dextran sodium sulfate (DSS). Colonic tumor xenograft models were developed in BALB/c-nu mice by subcutaneous injection with HCT116 and HT-29 cells. Intragastric administration of celastrol (2 mg/kg/d) for 14 weeks significantly increased the survival ratio and reduced the multiplicity of colonic neoplasms compared with AOM/DSS model mice. Mechanically, celastrol treatment significantly prevented AOM/DSS-induced up-regulation of expression levels of oncologic markers including mutated p53 and phospho-p53, β-catenin and proliferating cell nuclear antigen (PCNA). In addition, treatment with celastrol inhibited inflammatory responses, as indicated by the decrease of serum tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6, down-regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), and inactivation of nuclear factor κB (NF-κB). Moreover, celastrol obviously suppressed epithelial-mesenchymal transition (EMT) through up-regulating E-cadherin and down-regulating N-cadherin, Vimentin and Snail. Additionally, we also demonstrated that celastrol inhibited human CRC cell proliferation and attenuated colonic xenograft tumor growth via reversing EMT. Taken together, celastrol could effectively ameliorate UC-CRC by suppressing inflammatory responses and EMT, suggesting a potential drug candidate for UC-CRC therapy. PMID:26793111

δ- and γ-tocopherols, but not α-tocopherol, inhibit colon carcinogenesis in azoxymethane-treated F344 rats.

PubMed

Guan, Fei; Li, Guangxun; Liu, Anna B; Lee, Mao-Jung; Yang, Zhihong; Chen, Yu-Kuo; Lin, Yong; Shih, Weichung; Yang, Chung S

2012-04-01

The cancer preventive activity of vitamin E has been extensively discussed, but the activities of specific forms of tocopherols have not received sufficient attention. Herein, we compared the activities of δ-tocopherol (δ-T), γ-T, and α-T in a colon carcinogenesis model. Male F344 rats, seven weeks old, were given two weekly subcutaneous injections of azoxymethane (AOM) each at a dose of 15 mg/kg body weight. Starting 1 week before the AOM injection, the animals were maintained on a modified AIN76A diet, or the same diet containing 0.2% of δ-T, γ-T, α-T, or a γ-T-rich mixture of tocopherols (γ-TmT), until the termination of the experiment at 8 weeks after the second AOM injection. δ-T treatment showed the strongest inhibitory effect, decreasing the numbers of aberrant crypt foci by 62%. γ-T and γ-TmT were also effective, but α-T was not. Immunohistochemical analysis showed that δ-T and γ-T treatments reduced the levels of 4-hydroxynonenal and nitrotyrosine and the expression of cyclin D1 in the colon, preserved the expression of PPAR-γ, and decreased the serum levels of prostaglandin E2 and 8-isoprostane. Supplementation with 0.2% δ-T, γ-T, or α-T increased the respective levels of tocopherols and their side-chain degradation metabolites in the serum and colon tissues. Rather high concentrations of δ-T and γ-T and their metabolites were found in colon tissues. Our study provides the first evidence for the much higher cancer preventive activity of δ-T and γ-T than α-T in a chemically induced colon carcinogenesis model. It further suggests that δ-T is more effective than γ-T. 2012 AACR

δ- and γ-Tocopherols, but not α-Tocopherol, Inhibit Colon Carcinogenesis in Azoxymethane-Treated F344 Rats

PubMed Central

Guan, Fei; Li, Guangxun; Liu, Anna B; Lee, Mao-Jung; Yang, Zhihong; Chen, Yu-Kuo; Lin, Yong; Shih, Weichung; Yang, Chung S

2012-01-01

The cancer preventive activity of vitamin E has been extensively discussed, but the activities of specific forms of tocopherols have not received sufficient attention. Herein, we compared the activities of δ-tocopherol (δ-T), γ-T and α-T in a colon carcinogenesis model. Male F344 rats, 7 weeks old, were given 2 weekly subcutaneous injections of azoxymethane (AOM) each at a dose of 15 mg/kg body weight. Starting 1 week before the AOM injection, the animals were maintained on a modified AIN76A diet, or the same diet containing 0.2% of δ-T, γ-T, α-T or a γ-T-rich mixture of tocopherols (γ-TmT), until the termination of the experiment at 8 weeks after the second AOM injection. δ-T treatment showed the strongest inhibitory effect, decreasing the numbers of aberrant crypt foci by 62%. γ-T and γ-TmT were also effective, but α-T was not. Immunohistochemical analysis showed that δ-T and γ-T treatments reduced the levels of 4-hydroxynonenal and nitrotyrosine and the expression of cyclin D1 in the colon, preserved the expression of PPAR-γ, and decreased the serum levels of prostaglandin E2 and 8-isoprostane. Supplementation with 0.2% δ-T, γ-T or α-T increased the respective levels of tocopherols and their side-chain degradation metabolites in the serum and colon tissues. Rather high concentrations of δ-T and γ-T and their metabolites were found in colon tissues. Our study provides the first evidence for the much higher cancer preventive activity of δ-T and γ-T than α-T in a chemically-induced colon carcinogenesis model. It further suggests that δ-T is more effective than γ-T. PMID:22366914

Visualizing in situ translational activity for identifying and sorting slow-growing archaeal-bacterial consortia

DOE PAGES

Hatzenpichler, Roland; Connon, Stephanie A.; Goudeau, Danielle; ...

2016-06-28

To understand the biogeochemical roles of microorganisms in the environment, it is important to determine when and under which conditions they are metabolically active. Bioorthogonal noncanonical amino acid tagging (BONCAT) can reveal active cells by tracking the incorporation of synthetic amino acids into newly synthesized proteins. The phylogenetic identity of translationally active cells can be determined by combining BONCAT with rRNA-targeted fluorescence in situ hybridization (BONCAT-FISH). In theory, BONCAT-labeled cells could be isolated with fluorescence-activated cell sorting (BONCAT-FACS) for subsequent genetic analyses. Here, in the first application, to our knowledge, of BONCAT-FISH and BONCAT-FACS within an environmental context, we probemore » the translational activity of microbial consortia catalyzing the anaerobic oxidation of methane (AOM), a dominant sink of methane in the ocean. These consortia, which typically are composed of anaerobic methane-oxidizing archaea (ANME) and sulfate-reducing bacteria, have been difficult to study due to their slow in situ growth rates, and fundamental questions remain about their ecology and diversity of interactions occurring between ANME and associated partners. Our activity-correlated analyses of > 16,400 microbial aggregates provide the first evidence, to our knowledge, that AOM consortia affiliated with all five major ANME clades are concurrently active under controlled conditions. Surprisingly, sorting of individual BONCAT-labeled consortia followed by whole-genome amplification and 16S rRNA gene sequencing revealed previously unrecognized interactions of ANME with members of the poorly understood phylum Verrucomicrobia. This finding, together with our observation that ANME-associated Verrucomicrobia are found in a variety of geographically distinct methane seep environments, suggests a broader range of symbiotic relationships within AOM consortia than previously thought.« less

Age of Sulfate Methane Transition Zone Determined by Modelling Barium Sulfate Growth

NASA Astrophysics Data System (ADS)

Lin, S.; Wang, W. C.; Lien, K. L.; Liu, C. C.; Fan, L. F.

2017-12-01

Methane seep to the sediment/water interface could initiate anaerobic methane oxidation (AOM) with subsequent build up of chemosynthetic community, carbonate, pyrite and a number of other authigenic mineral formation. Determination the duration, sequence and time of methane seeps are keys to understand how methane seep to the environment and degree of alteration to the vicinity area. However, limited method existed in defining time of methane seep since there are some known problems involving typical dating methods, i.e. old carbon on C14 of fossil test or authigenic carbonate, thorium from surrounding matrix on U/Th authigenic carbonate dating. In this study, we have employed barium determination method (Dickens, 2001) to model timing of methane seep at two locations in the South China Sea. Our objective is to compare timing of the barium accumulation near the sulfate methane transition zone (SMTZ) on these two different locations and to seek if a similar mechanism driving the methane seep at two locations far apart. Dissolved barium, total sediment barium and aluminum were measured as well as pore water sulfate, and sediment pyrite concentrations. Time for the barium sulfate accumulation is calculated by: T = C/F, C= ∫ I x p x (1-Ø) Our results show that SMTZ is stabilized at each site for a duration of about 4000-5000 years. AOM process have been active at both sites at about the same time. In conjunction, pyrite also accumulated at a depth near the SMTZ as a result of methane oxidation. This result show that AOM could stay at the SMTZ for a relatively long period of time, on a scale of thousands of years.

Visualizing in situ translational activity for identifying and sorting slow-growing archaeal-bacterial consortia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatzenpichler, Roland; Connon, Stephanie A.; Goudeau, Danielle

To understand the biogeochemical roles of microorganisms in the environment, it is important to determine when and under which conditions they are metabolically active. Bioorthogonal noncanonical amino acid tagging (BONCAT) can reveal active cells by tracking the incorporation of synthetic amino acids into newly synthesized proteins. The phylogenetic identity of translationally active cells can be determined by combining BONCAT with rRNA-targeted fluorescence in situ hybridization (BONCAT-FISH). In theory, BONCAT-labeled cells could be isolated with fluorescence-activated cell sorting (BONCAT-FACS) for subsequent genetic analyses. Here, in the first application, to our knowledge, of BONCAT-FISH and BONCAT-FACS within an environmental context, we probemore » the translational activity of microbial consortia catalyzing the anaerobic oxidation of methane (AOM), a dominant sink of methane in the ocean. These consortia, which typically are composed of anaerobic methane-oxidizing archaea (ANME) and sulfate-reducing bacteria, have been difficult to study due to their slow in situ growth rates, and fundamental questions remain about their ecology and diversity of interactions occurring between ANME and associated partners. Our activity-correlated analyses of > 16,400 microbial aggregates provide the first evidence, to our knowledge, that AOM consortia affiliated with all five major ANME clades are concurrently active under controlled conditions. Surprisingly, sorting of individual BONCAT-labeled consortia followed by whole-genome amplification and 16S rRNA gene sequencing revealed previously unrecognized interactions of ANME with members of the poorly understood phylum Verrucomicrobia. This finding, together with our observation that ANME-associated Verrucomicrobia are found in a variety of geographically distinct methane seep environments, suggests a broader range of symbiotic relationships within AOM consortia than previously thought.« less

Pronounced Structural and Functional Damage in Early Adult Pediatric-Onset Multiple Sclerosis with No or Minimal Clinical Disability.

PubMed

Giorgio, Antonio; Zhang, Jian; Stromillo, Maria Laura; Rossi, Francesca; Battaglini, Marco; Nichelli, Lucia; Mortilla, Marzia; Portaccio, Emilio; Hakiki, Bahia; Amato, Maria Pia; De Stefano, Nicola

2017-01-01

Pediatric-onset multiple sclerosis (POMS) may represent a model of vulnerability to damage occurring during a period of active maturation of the human brain. Whereas adaptive mechanisms seem to take place in the POMS brain in the short-medium term, natural history studies have shown that these patients reach irreversible disability, despite slower progression, at a significantly younger age than adult-onset MS (AOMS) patients. We tested for the first time whether significant brain alterations already occurred in POMS patients in their early adulthood and with no or minimal disability ( n  = 15) in comparison with age- and disability-matched AOMS patients ( n  = 14) and to normal controls (NC, n  = 20). We used a multimodal MRI approach by modeling, using FSL, voxelwise measures of microstructural integrity of white matter tracts and gray matter volumes with those of intra- and internetwork functional connectivity (FC) (analysis of variance, p  ≤ 0.01, corrected for multiple comparisons across space). POMS patients showed, when compared with both NC and AOMS patients, altered measures of diffusion tensor imaging (reduced fractional anisotropy and/or increased diffusivities) and higher probability of lesion occurrence in a clinically eloquent region for physical disability such as the posterior corona radiata. In addition, POMS patients showed, compared with the other two groups, reduced long-range FC, assessed from resting functional MRI, between default mode network and secondary visual network, whose interaction subserves important cognitive functions such as spatial attention and visual learning. Overall, this pattern of structural damage and brain connectivity disruption in early adult POMS patients with no or minimal clinical disability might explain their unfavorable clinical outcome in the long term.

Identification of the dominant sulfate-reducing bacterial partner of anaerobic methanotrophs of the ANME-2 clade.

PubMed

Schreiber, Lars; Holler, Thomas; Knittel, Katrin; Meyerdierks, Anke; Amann, Rudolf

2010-08-01

The anaerobic oxidation of methane (AOM) with sulfate as terminal electron acceptor is mediated by consortia of methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). Whereas three clades of ANME have been repeatedly studied with respect to phylogeny, key genes and genomic capabilities, little is known about their sulfate-reducing partner. In order to identify the partner of anaerobic methanotrophs of the ANME-2 clade, bacterial 16S rRNA gene libraries were constructed from cultures highly enriched for ANME-2a and ANME-2c in consortia with Deltaproteobacteria of the Desulfosarcina/Desulfococcus group (DSS). Phylogenetic analysis of those and publicly available sequences from AOM sites supported the hypothesis by Knittel and colleagues that the DSS partner belongs to the diverse SEEP-SRB1 cluster. Six subclusters of SEEP-SRB1, SEEP-SRB1a to SEEP-SRB1f, were proposed and specific oligonucleotide probes were designed. Using fluorescence in situ hybridization on samples from six different AOM sites, SEEP-SRB1a was identified as sulfate-reducing partner in up to 95% of total ANME-2 consortia. SEEP-SRB1a cells exhibited a rod-shaped, vibrioid, or coccoid morphology and were found to be associated with subgroups ANME-2a and ANME-2c. Moreover, SEEP-SRB1a was also detected in 8% to 23% of ANME-3 consortia in Haakon Mosby Mud Volcano sediments, previously described to be predominantly associated with SRB of the Desulfobulbus group. SEEP-SRB1a contributed to only 0.3% to 0.7% of all single cells in almost all samples indicating that these bacteria are highly adapted to a symbiotic relationship with ANME-2. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

A spatio-temporally compensated acousto-optic scanner for two-photon microscopy providing large field of view.

PubMed

Kremer, Y; Léger, J-F; Lapole, R; Honnorat, N; Candela, Y; Dieudonné, S; Bourdieu, L

2008-07-07

Acousto-optic deflectors (AOD) are promising ultrafast scanners for non-linear microscopy. Their use has been limited until now by their small scanning range and by the spatial and temporal dispersions of the laser beam going through the deflectors. We show that the use of AOD of large aperture (13mm) compared to standard deflectors allows accessing much larger field of view while minimizing spatio-temporal distortions. An acousto-optic modulator (AOM) placed at distance of the AOD is used to compensate spatial and temporal dispersions. Fine tuning of the AOM-AOD setup using a frequency-resolved optical gating (GRENOUILLE) allows elimination of pulse front tilt whereas spatial chirp is minimized thanks to the large aperture AOD.

Yerba mate tea and mate saponins prevented azoxymethane-induced inflammation of rat colon through suppression of NF-κB p65ser(311) signaling via IκB-α and GSK-3β reduced phosphorylation.

PubMed

Puangpraphant, Sirima; Dia, Vermont P; de Mejia, Elvira Gonzalez; Garcia, Guadalupe; Berhow, Mark A; Wallig, Matthew A

2013-01-01

Yerba mate tea (YMT) has a chemopreventive role in a variety of inflammatory diseases. The objective was to determine the capability of YMT and mate saponins to prevent azoxymethane (AOM)-induced colonic inflammation in rats. YMT (2% dry leaves, w/v, as a source of drinking fluid) (n = 15) and mate saponins (0.01% in the diet, at a concentration present in one cup of YMT) (n = 15) were given ad libitum to rats 2 weeks prior to AOM-injection until the end of the study; while control rats (n = 15) received a basal diet and drinking water. After 8-weeks of study, total colonic mucosa was scraped (n = 3 rats/group) and the remaining colons (n =12 rats/group) were cut into three equal sections and aberrant crypt foci (ACF) were analyzed. YMT reduced ACF formation from 113 (control group) to 89 (P < 0.05). YMT and mate saponins reduced the expression of proinflammatory molecules COX-2 and iNOS with concomitant reduction in p-p65 (P < 0.05). Immunohistochemical analysis of the formalin-fixed middle colons showed that YMT and mate saponins reduced the expression of p-p65(ser311) by 45.7% and 43.1%, respectively, in comparison to the control (P < 0.05). In addition, the expression of molecules upstream of NF-κB such as p-IκB-α and p-GSK-3β(Y216) was downregulated by YMT 24.7% and 24.4%, respectively (P < 0.05). Results suggest the mechanism involved in the chemopreventive effect of YMT and mate saponin consumption in AOM induced-colonic inflammation in rats is through inhibition of NF-κB. Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.

Optical properties of algogenic organic matter within the growth period of Chlorella sp. and predicting their disinfection by-product formation.

PubMed

Hua, Lap-Cuong; Lin, Jr-Lin; Syue, Ming-Yang; Huang, Chihpin; Chen, Pei-Chung

2018-04-15

Algogenic organic matter (AOM) in eutrophic waters is a well-known precursor to disinfection by-product (DBP) formation in drinking water. This purpose of this study is (i) to characterize the optical properties of AOM origins, including intra- (IOM) and extra-cellular organic matter (EOM), derived from Chlorella sp. growth as precursors to two major carbonaceous DBPs (C-DBPs), trihalomethanes (THMs) and haloacetic acids (HAAs) and (ii) to correlate these optical properties with THM and HAA formation potential (FP) in order to predict DBP formation. The results show that both EOM and IOM had low UV 254 and UV 280 absorbance during their entire growth phase. While IOM chiefly comprised of aromatic proteins and soluble microbial products-like substances (80% of average fluorescent intensity-AFI), EOM spectra were rich in humic- and fulvic-like substances (60% AFI). However, its chemical nature likely differed from terrestrial humics. In DBPFP tests, IOM was a higher-yielding precursor of THMs and HAAs compared to EOM, regardless its growth status. Consequently, C-DBPFP of IOM was always higher than EOM during four growth phases. Results from DBP tests also showed insignificant variation of EOM-derived THMFP and HAAFP during the algal growth phase, while the algal growth status strongly influenced the yields of IOM-derived THMFP and HAAFP. From correlation analysis, our results showed no correlation between UV absorbance with THMFP and HAAFP. Conversely, the regional AFI showed a good correlation with HAAFP and C-DBPFP. Predicting models based on AFI for the formation of HAAs and C-DBPs consequently yielded great predictability for laboratory AOM-containing water samples, with a coefficient of determination R 2 =0.879, p<0.01 and R 2 =0.846, p<0.01. This study indicates a promising application of fluorescent spectra for predicting DBPs derived from algae-rich water sources. Copyright © 2017 Elsevier B.V. All rights reserved.

Cost-effectiveness and cost utility analysis of three pneumococcal conjugate vaccines in children of Peru

PubMed Central

2013-01-01

Background The clinical and economic burden associated with invasive and non-invasive pneumococcal and non-typeable Haemophilus influenzae (NTHi) diseases is substantial in the Latin America and Caribbean region, where pneumococcal vaccines have only been introduced to a few countries. This study analyzed the cost-effectiveness and cost utility of three different pneumococcal conjugate vaccines (PCVs) for Peru. Methods A Markov model that simulated the disease processes in a birth cohort over a lifetime, within 1,128 month cycles was used to evaluate the cost-effectiveness of 10-valent pneumococcal NTHi protein D conjugate vaccine (PHiD-CV) and 7- and 13-valent PCVs (PCV-7 and PCV-13). Expected quality-adjusted life years (QALYs), cost-savings and incremental cost-effectiveness ratios (ICERs) were calculated. Results Without vaccination, pneumonia was associated with the greatest health economic burden (90% of QALYs lost and 63% of lifetime direct medical costs); while acute otitis media (AOM) was responsible for 1% of QALYs lost and 25% of direct medical costs. All vaccines were predicted to be cost-effective for Peru, with PHiD-CV being most cost-effective. PHiD-CV was predicted to generate 50 more QALYs gained and required a reduced investment (−US$ 3.4 million) versus PCV-13 (discounted data), and was therefore dominant and cost saving. The probabilistic sensitivity analysis showed that PHiD-CV generated more QALYs gained at a reduced cost than PCV-13 in 84% of the simulations and less QALYs gains at a reduced cost in 16%. Additional scenarios using different assumptions on vaccine efficacies based on previous evidence were explored, but no significant change in the overall cost-effective results were observed. Conclusions The results of this modeling study predict that PCVs are likely to be a cost-effective strategy to help relieve the epidemiological and economic burden associated with pediatric pneumococcal and NTHi diseases for Peru. PHiD-CV is likely to be a dominant (better health gains at a reduced net cost) intervention compared to PCV-13 or PCV-7. The most significant drivers for these results are the better health and economic profile of PHiD-CV against AOM and its reduced cost per dose available through the PAHO Revolving Fund in the LAC region. PMID:24171921

Cost-effectiveness and cost utility analysis of three pneumococcal conjugate vaccines in children of Peru.

PubMed

Gomez, Jorge Alberto; Tirado, Juan Carlos; Navarro Rojas, Aldo Amador; Castrejon Alba, Maria Mercedes; Topachevskyi, Oleksandr

2013-10-30

The clinical and economic burden associated with invasive and non-invasive pneumococcal and non-typeable Haemophilus influenzae (NTHi) diseases is substantial in the Latin America and Caribbean region, where pneumococcal vaccines have only been introduced to a few countries. This study analyzed the cost-effectiveness and cost utility of three different pneumococcal conjugate vaccines (PCVs) for Peru. A Markov model that simulated the disease processes in a birth cohort over a lifetime, within 1,128 month cycles was used to evaluate the cost-effectiveness of 10-valent pneumococcal NTHi protein D conjugate vaccine (PHiD-CV) and 7- and 13-valent PCVs (PCV-7 and PCV-13). Expected quality-adjusted life years (QALYs), cost-savings and incremental cost-effectiveness ratios (ICERs) were calculated. Without vaccination, pneumonia was associated with the greatest health economic burden (90% of QALYs lost and 63% of lifetime direct medical costs); while acute otitis media (AOM) was responsible for 1% of QALYs lost and 25% of direct medical costs. All vaccines were predicted to be cost-effective for Peru, with PHiD-CV being most cost-effective. PHiD-CV was predicted to generate 50 more QALYs gained and required a reduced investment (-US$ 3.4 million) versus PCV-13 (discounted data), and was therefore dominant and cost saving. The probabilistic sensitivity analysis showed that PHiD-CV generated more QALYs gained at a reduced cost than PCV-13 in 84% of the simulations and less QALYs gains at a reduced cost in 16%. Additional scenarios using different assumptions on vaccine efficacies based on previous evidence were explored, but no significant change in the overall cost-effective results were observed. The results of this modeling study predict that PCVs are likely to be a cost-effective strategy to help relieve the epidemiological and economic burden associated with pediatric pneumococcal and NTHi diseases for Peru. PHiD-CV is likely to be a dominant (better health gains at a reduced net cost) intervention compared to PCV-13 or PCV-7. The most significant drivers for these results are the better health and economic profile of PHiD-CV against AOM and its reduced cost per dose available through the PAHO Revolving Fund in the LAC region.

Dietary Nanosized Lactobacillus plantarum Enhances the Anticancer Effect of Kimchi on Azoxymethane and Dextran Sulfate Sodium-Induced Colon Cancer in C57BL/6J Mice.

PubMed

Lee, Hyun Ah; Kim, Hyunung; Lee, Kwang-Won; Park, Kun-Young

2016-01-01

This study was undertaken to evaluate enhancement of the chemopreventive properties of kimchi by dietary nanosized Lactobacillus (Lab.)plantarum (nLp) in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis-associated colorectal cancer C57BL/6J mouse model. nLp is a dead, shrunken, processed form of Lab. Plantarum isolated from kimchi that is 0.5-1.0 µm in size. The results obtained showed that animals fed kimchi with nLp (K-nLp) had longer colons and lower colon weights/length ratios and developed fewer tumors than mice fed kimchi alone (K). In addition, K-nLp administration reduced levels of proinflammatory cytokine serum levels and mediated the mRNA and protein expressions of inflammatory, apoptotic, and cell-cycle markers to suppress inflammation and induce tumor-cell apoptosis and cell-cycle arrest. Moreover, it elevated natural killer-cell cytotoxicity. The study suggests adding nLp to kimchi could improve the suppressive effect of kimchi on AOM/DSS-induced colorectal cancer. These findings indicate nLp has potential use as a functional chemopreventive ingredient in the food industry.

Induction of colonic aberrant crypts in mice by feeding apparent N-nitroso compounds derived from hot dogs

PubMed Central

Davis, Michael E; Lisowyj, Michal P; Zhou, Lin; Wisecarver, James L; Gulizia, James M; Shostrom, Valerie K; Naud, Nathalie; Corpet, Denis E; Mirvish, Sidney S

2012-01-01

Nitrite-preserved meats (e.g., hot dogs) may help cause colon cancer because they contain N-nitroso compounds. We tested whether purified hot-dog-derived total apparent N-nitroso compounds (ANC) could induce colonic aberrant crypts, which are putative precursors of colon cancer. We purified ANC precursors in hot dogs and nitrosated them to produce ANC. In preliminary tests, CF1 mice received 1 or 3 i.p. injections of 5mg azoxymethane (AOM)/kg. In Experiments 1 and 2, female A/J mice received ANC in diet. In Experiment 1, ANC dose initially dropped sharply because the ANC precursors had mostly decomposed but, later in Experiment 1 and throughout Experiment 2, ANC remained at 85 nmol/g diet. Mice were killed after 8 (AOM tests) or 17–34 (ANC tests) wk. Median numbers of aberrant crypts in the distal 2 cm of the colon for 1 and 3 AOM injections, CF1 controls, ANC (Experiment 1), ANC (Experiment 2),and untreated A/J mice were 31, 74, 12, 20, 12, and 5–6, with P < 0.01 for both ANC tests. Experiment 2 showed somewhat increased numbers of colonic mucin-depleted foci in the ANC-treated group. We conclude that hot-dog-derived ANC induced significant numbers of aberrant crypts in the mouse colon. PMID:22293095

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS.

PubMed

Lin, Zhiyong; Sun, Xiaoming; Peckmann, Jörn; Lu, Yang; Strauss, Harald; Xu, Li; Lu, Hongfeng; Teichert, Barbara M A

2017-08-31

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and organiclastic sulfate reduction (OSR) in marine sediments. However, unravelling the complex pyritization sequence is a challenge because of the coexistence of different sequentially formed pyrite phases. This manuscript describes a sample preparation procedure that enables the use of secondary ion mass spectroscopy (SIMS) to obtain in situ δ 34 S values of various pyrite generations. This allows researchers to constrain how SO4-AOM affects pyritization in methane-bearing sediments. SIMS analysis revealed an extreme range in δ 34 S values, spanning from -41.6 to +114.8‰, which is much wider than the range of δ 34 S values obtained by the traditional bulk sulfur isotope analysis of the same samples. Pyrite in the shallow sediment mainly consists of 34 S-depleted framboids, suggesting early diagenetic formation by OSR. Deeper in the sediment, more pyrite occurs as overgrowths and euhedral crystals, which display much higher SIMS δ 34 S values than the framboids. Such 34 S-enriched pyrite is related to enhanced SO4-AOM at the sulfate-methane transition zone, postdating OSR. High-resolution in situ SIMS sulfur isotope analyses allow for the reconstruction of the pyritization processes, which cannot be resolved by bulk sulfur isotope analysis.

Penicillin reduces eustachian tube gland tissue changes in acute otitis media.

PubMed

Andersen, Henrik; Thomsen, Jens; Cayé-Thomasen, Per

2005-08-01

The volume of the mucous paratubal glands and the number of the mucus-producing goblet cells in the middle ear and Eustachian tube (ET) are increased after experimental acute otitis media (AOM). The present investigation examines a potential effect of penicillin on the changes in goblet cell density and gland structures of the ET during and after AOM. Middle ear inoculation of Streptococcus pneumoniae in 50 rats. Two days later, 25 rats were given penicillin V as one daily dose for 5 days. Twenty-five rats received no treatment. Five animals from each group were sacrificed on days 4, 8, 16, 90, and 180. The ET was dissected and decalcified, followed by paraffin embedding, serial transverse sectioning, and PAS/alcian blue staining. The goblet cell density and the paratubal gland composition and volume were determined in every 20th section, using a light microscope. Penicillin reduced the increase of goblet cell density from day 8 and through 6 months, whereas the increase of the paratubal mucous gland volume was unaffected by treatment. We conclude that penicillin reduces the increase of ET goblet cell density during and after acute otitis media, whereas the paratubal gland volume remains unaffected. An increased mucosal secretory capacity and indicated excessive secretion of mucus may contribute to the deteriorated ET function found after AOM and thus predispose, sustain, or aggravate middle ear disease. This may be prevented by penicillin treatment.

Acousto-optic modulation in diode pumped solid state lasers

NASA Astrophysics Data System (ADS)

Jabczynski, Jan K.; Zendzian, Waldemar; Kwiatkowski, Jacek

2007-02-01

The main properties of acousto-optic modulators (AOM) applied in laser technology are presented and discussed in the paper. The critical review of application of AOMs in several types of diode pumped solid state lasers (DPSSL) is given. The short description of few DPSSLs developed in our group is presented in the following chapters of the paper. The parameters of a simple AO-Q-switched Nd:YVO 4 laser (peak power up to 60 kW, pulse duration of 5-15 ns, repetition rate in the range 10-100 kHz, with average power above 5 W) are satisfactory for different application as follows: higher harmonic generation, pumping of 'eye-safe' OPOs etc. The achieved brightness of 10 17 W/m2/srd is comparable to the strongest technological Q-switched lasers of kW class of average power. The main aim of paper is to present novel type of lasers with acousto-optic modulation namely: AO-q-switched and mode locked (AO-QML) lasers. We have designed the 3.69-m long Z-type resonator of the frequency matched to the RF frequency of AOM. As a gain medium the Nd:YVO 4 crystal end pumped by 20 W laser diode was applied. The energy of envelope of QML pulse train was up to 130 μJ with sub-nanosecond mode locked pulse of maximum 30-μJ energy.

A flexible master oscillator for a pulse-burst laser system

NASA Astrophysics Data System (ADS)

Den Hartog, D. J.; Young, W. C.

2015-12-01

A new master oscillator is being installed in the pulse-burst laser system used for high-rep-rate Thomson scattering on the MST experiment. This new master oscillator will enable pulse repetition rates up to 1 MHz, with the ability to program a burst of pulses with arbitrary and varying time separation between each pulse. In addition, the energy of each master oscillator pulse can be adjusted to compensate for gain variations in the power amplifier section of the laser system. This flexibility is accomplished by chopping a CW laser source with a high-bandwidth acousto-optic modulator (AOM). The laser source is a Laser Quantum ventus 1064 diode-pumped solid-state laser with continuous output power variable from 100 to 500 mW. The 1064 nm, 2.7 mm diameter polarized beam is focused into the gallium phosphide crystal of a Brimrose AOM, which deflects the beam by approximately 60 mR when driven by the 400 MHz fixed frequency driver. Beam deflection is controlled by a simple digital input pulse, and is capable of producing deflected pulses of less than 20 ns width at repetition rates much greater than 1 MHz. These deflected pulses from the output of the AOM are collimated and propagated into the laser amplifier system, where they will be amplified to ~ 2 J/pulse and injected into the MST plasma.

An assessment of the shared-decision model in parents of children with acute otitis media.

PubMed

Merenstein, Dan; Diener-West, Marie; Krist, Alex; Pinneger, Matthew; Cooper, Lisa A

2005-12-01

Medicine is shifting from a doctor-centered approach to a model entailing more shared decision-making. Many organizations now recommend a shared-decision approach to treating children with acute otitis media (AOM). Our primary objectives in this study were to assess (1) which style of decision-making on the physician's part would most effectively reduce parents' proclivity to use antibiotics for treatment of their child's AOM and (2) parental satisfaction with different doctor-patient decision-making styles. We conducted a cross-sectional survey to examine how parents respond to doctor-patient communication styles in 3 clinical vignettes that presented 2 versions of a shared-decision model (SDM) and 1 paternalistic model. Parents were randomly assigned to receive 1 of 3 vignettes. The main predictor variable was the vignette assignment, and the main outcomes were (1) parent proclivity to use antibiotics and (2) parent ratings of care by the physician in the vignette. Using logistic regression, we adjusted for caregivers' age, gender, income, knowledge of antibiotics, decision-making preference, confidence in physician, and length of relationship with personal physician. Four hundred sixty-six parents met inclusion criteria, with a response rate of 94%. General characteristics were similar across vignette assignment groups. Parents who received the paternalistic-model vignettes were more likely to say that they would use antibiotics than those who received the SDM vignettes (odds ratio: 4.9; 95% confidence interval: 2.3-10.6). This result remained statistically significant after adjustment for potential confounders. In addition, parents in the shared-decision groups were more satisfied (93% and 84%) than those in the paternalistic-model group (76%). To our knowledge, this is the first study to examine parent interest, acceptance, and satisfaction with the SDM. Our findings suggest that shared decision-making for AOM may lead to less antibiotic usage and higher levels of parental satisfaction. Although more studies are needed to examine how best to incorporate parents in the SDM, our study serves as an example of the potential benefit of this approach in pediatric medicine.

Enrichment of sulfate reducing anaerobic methane oxidizing community dominated by ANME-1 from Ginsburg Mud Volcano (Gulf of Cadiz) sediment in a biotrickling filter.

PubMed

Bhattarai, Susma; Cassarini, Chiara; Rene, Eldon R; Zhang, Yu; Esposito, Giovanni; Lens, Piet N L

2018-07-01

This study was performed to enrich anaerobic methane-oxidizing archaea (ANME) present in sediment from the Ginsburg Mud Volcano (Gulf of Cadiz) in a polyurethane foam packed biotrickling filter (BTF). The BTF was operated at 20 (±2) °C, ambient pressure with continuous supply of methane for 248 days. Sulfate reduction with simultaneous sulfide production (accumulating ∼7 mM) after 200 days of BTF operation evidenced anaerobic oxidation of methane (AOM) coupled to sulfate reduction. High-throughput sequence analysis of 16S rRNA genes showed that after 248 days of BTF operation, the ANME clades enriched to more than 50% of the archaeal sequences, including ANME-1b (40.3%) and ANME-2 (10.0%). Enrichment of the AOM community was beneficial to Desulfobacteraceae, which increased from 0.2% to 1.8%. Both the inoculum and the BTF enrichment contained large populations of anaerobic sulfur oxidizing bacteria, suggesting extensive sulfur cycling in the BTF. Copyright © 2018 Elsevier Ltd. All rights reserved.

Anaerobic methane oxidation in low-organic content methane seep sediments

USGS Publications Warehouse

Pohlman, John W.; Riedel, Michael; Bauer, James E.; Canuel, Elizabeth A.; Paull, Charles K.; Lapham, Laura; Grabowski, Kenneth S.; Coffin, Richard B.; Spence, George D.

2013-01-01

Sulfate-dependent anaerobic oxidation of methane (AOM) is the key sedimentary microbial process limiting methane emissions from marine sediments and methane seeps. In this study, we investigate how the presence of low-organic content sediment influences the capacity and efficiency of AOM at Bullseye vent, a gas hydrate-bearing cold seep offshore of Vancouver Island, Canada. The upper 8 m of sediment contains 14C. A fossil origin for the DIC precludes remineralization of non-fossil OM present within the sulfate zone as a significant contributor to pore water DIC, suggesting that nearly all sulfate is available for anaerobic oxidation of fossil seep methane. Methane flux from the SMT to the sediment water interface in a diffusion-dominated flux region of Bullseye vent was, on average, 96% less than at an OM-rich seep in the Gulf of Mexico with a similar methane flux regime. Evidence for enhanced methane oxidation capacity within OM-poor sediments has implications for assessing how climate-sensitive reservoirs of sedimentary methane (e.g., gas hydrate) will respond to ocean warming, particularly along glacially-influenced mid and high latitude continental margins.

The protective effects of fermented kefir milk on azoxymethane-induced aberrant crypt formation in mice colon.

PubMed

Melo, Aline Freitas de Paula; Mendonça, Monique Culturato Padilha; Rosa-Castro, Raquel de Mendonça

2018-06-01

Kefir is a probiotic fermented milk product produced from grains with a complex composition of bacteria and yeasts that live in a symbiotic association. Anti-proliferative, anti-inflammatory, and anti-mutagenic effects are some of the health beneficial properties of kefir grains. The present study was conducted to evaluate whether regular consumption of kefir milk would be capable of preventing the development of pre-neoplastic lesions induced by azoxymethane (AOM). Aberrant crypt foci were induced in BALB-c mice via 2 subcutaneous injections of azoxymethane (15 mg/kg) and kefir was administered by daily gavage for 8 weeks (5 ml/kg). Additionally, bacterial growth was monitored in pasteurized and ultra-high temperature (UHT) treated milk to compare different fermentation conditions. Our results showed that UHT milk presented better growth of Lactobacillus acidophilus colonies. The aberrant crypt foci were attenuated by approximately 43% (height) and 20% (width) in the kefir group compared to AOM group, suggesting that kefir treatment may contribute to prevent and control the growth of intestinal neoplastic cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

The connection between acute otitis media and the acute abdomen.

PubMed

Masood, Imran; Hendriksz, Tami

2017-06-22

A female aged 9 years with a recent episode of acute otitis media (AOM) presented to her primary care physician with complaints of severe abdominal pain with right lower quadrant rebound tenderness, suggestive of an acute surgical abdomen. Neurological examination was normal on presentation. She was transferred to the local children's hospital for workup of appendicitis, during which she began exhibiting ataxia and slurred speech. Further evaluation revealed mastoiditis, venous sinus thrombosis and subdural empyema. Appendicitis was ruled out. We describe the first documented case of neurological complications of AOM presenting as an acute surgical abdomen without initial neurological findings. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Will Parents Participate in and Comply with Programs and Regimens Using Xylitol for Preventing Acute Otitis Media in Their Children?

ERIC Educational Resources Information Center

Danhauer, Jeffrey L.; Johnson, Carole E.; Baker, Jason A.; Ryu, Jung A.; Smith, Rachel A.; Umeda, Claire J.

2015-01-01

Purpose: Antiadhesive properties in xylitol, a natural sugar alcohol, can help prevent acute otitis media (AOM) in children by inhibiting harmful bacteria from colonizing and adhering to oral and nasopharyngeal areas and traveling to the Eustachian tube and middle ear. This study investigated parents' willingness to use and comply with a regimen…

Origin of lipid biomarkers in mud volcanoes from the Alboran Sea, western Mediterranean

NASA Astrophysics Data System (ADS)

López-Rodríguez, C.; Stadnitskaia, A.; De Lange, G. J.; Martínez-Ruíz, F.; Comas, M.

2014-06-01

Mud volcanoes (MVs) are the most prominent indicators of active methane/hydrocarbon venting at the seafloor on both passive and active continental margins. Their occurrence in the western Mediterranean is patent at the West Alboran Basin, where numerous MVs develop overlaying a major sedimentary depocentre containing overpressured shales. Although some of these MVs have been studied, the detailed biogeochemistry of expelled mud so far has not been examined in detail. This work provides the first results on the composition and origin of organic matter, anaerobic oxidation of methane (AOM) processes and general characteristics on MV dynamics using lipid biomarkers as the main tool. Lipid biomarker analysis was performed on MV expelled material (mud breccias) and interbedded hemipelagic sediments from Perejil, Kalinin and Schneider's Heart MVs located in the northwest margin of the Alboran Sea. The n alkane distributions and n alkane-derived indices (CPI and ACL), in combination with the epimerization degree of hopanes (22S/(22S+22R)) indicate that all studied mud breccia have a similar biomarker composition consisting of mainly thermally immature organic matter with an admixture of petroleum-derived compounds. This concordant composition indicates that common source strata must feed all three studied MVs. The past or present AOM activity was established using lipid biomarkers specific for anaerobic methanotrophic archaea (irregular isoprenoids and dialkyl glycerol diethers) and the depleted carbon isotope composition (δ13C) of crocetane/phytane. The presence of these lipid biomarkers, together with the low amounts of detected glycerol dialkyl glycerol tetraethers, is consistent with the dominance of anaerobic methanotrophs of the ANME-2 over ANME-1, at least in mud breccia from Perejil MVs. In contrast, the scarce presence or lack of these AOM-related lipid biomarkers in sediments from Kalinin and Schneider's Heart MVs, suggests that no recent active methane seepage has occurred at these sites. Moreover, the observed methane concentrations support the current activity of Perejil MV, and the very low methane seepage activity in Kalinin and Schneider's Heart MVs.

Large dosage amoxicillin/clavulanate, compared with azithromycin, for the treatment of bacterial acute otitis media in children.

PubMed

Hoberman, Alejandro; Dagan, Ron; Leibovitz, Eugene; Rosenblut, Andres; Johnson, Candice E; Huff, Anne; Bandekar, Rajesh; Wynne, Brian

2005-06-01

A large dosage pediatric formulation of amoxicillin/clavulanate with an improved pharmacokinetic/pharmacodynamic profile was developed to eradicate many penicillin-resistant strains of Streptococcus pneumoniae and Haemophilus influenzae (including beta-lactamase-producing strains). This randomized, investigator-blinded, multicenter trial examined treatment of bacterial acute otitis media (AOM) in children 6-30 months of age with amoxicillin/clavulanate (90/6.4 mg/kg/d in 2 divided doses for 10 days) versus azithromycin (10 mg/kg for 1 day followed by 5 mg/kg/d for 4 days). Tympanocentesis was performed at entry for bacteriologic assessment, at the on-therapy visit (day 4-6) to determine bacterial eradication and at any time before the end-of-therapy visit (day 12-14) if the child was categorized as experiencing clinical failure. Clinical assessments were performed at the on-therapy, end-of-therapy and follow-up (day 21-25) visits. We enrolled 730 children; AOM pathogens were isolated at baseline for 249 of the amoxicillin/clavulanate group and 245 of the azithromycin group. For children with AOM pathogens at baseline, clinical success rates at the end-of-therapy visit were 90.5% for amoxicillin/clavulanate versus 80.9% for azithromycin (P < 0.01), and those at the on-therapy and follow-up visits were 94.9% versus 88.0% and 80.3% versus 71.1%, respectively (all P < 0.05). At the on-therapy visit, pretherapy pathogens were eradicated for 94.2% of children receiving amoxicillin/clavulanate versus 70.3% of those receiving azithromycin (P < 0.001). Amoxicillin/clavulanate eradicated 96.0% of S. pneumoniae (92.0% of fully penicillin-resistant S. pneumoniae) and 89.7% of H. influenzae (85.7% [6 of 7 cases] of beta-lactamase-positive H. influenzae). Corresponding rates for azithromycin were 80.4% (54.5%) for S. pneumoniae and 49.1% (100% [1 of 1 case]) for H. influenzae (all P < 0.01 for between-drug comparisons). Amoxicillin/clavulanate was clinically and bacteriologically more effective than azithromycin among children with bacterial AOM, including cases caused by penicillin-resistant S. pneumoniae and beta-lactamase-positive H. influenzae.

Investigating the organic carbon cycle and the anaerobic oxidation of methane in the Guaymas Basin: a biogeochemical approach

NASA Astrophysics Data System (ADS)

Cathalot, C.; Decker, C.; Caprais, J.; Ruffine, L.; Le Bruchec, J.; Olu, K.

2013-12-01

The Guaymas Basin is a pretty unique environment located in the Gulf of California and characterized by the emanation of fluids enriched in hydrocarbon, mainly methane, and sulfides. In this peculiar environment, both cold seeps and hydrothermal vents co-exist very closely, and are separated only by a few kilometers. In addition, highly productive surface waters and strong terrestrial inputs are responsible for strong sedimentation rates in this area. This special geological system allows for the development of various and complex macrofaunal and/or bacterial assemblages, based on chemosynthetic activity. These sea-bottom communities have been previously described [1,2] and several studies have demonstrated the occurrence of Anaerobic Oxidation of Methane (AOM) in the shallow sediment layers. Nevertheless, the quantification of the biogeochemical processes (e.g. rates, relative proportions) involved in both ecosystems in relation with the associated communities, and their role in the local organic carbon (OC) cycle is still lacking. Using a diagenetic modeling approach, this study aims at studying the OC production and recycling processes by describing the biogeochemical pathways and their associated rates in the ecosystems from the Guaymas Basin. Twelve stations presenting distinct biological assemblages (microbial mats, vesicomyids and bare sediment) were selected among both cold-seeps and hydrothermal vents sites from the Guaymas basin. A transport-reaction model including respiration, sulfate reduction, methanogenesis and AOM was developed and applied to each station. To constrain the model, at each station, cores were sampled using an ROV and the pore-waters extracted using Rhizon syringes. Pore-water concentrations of CH4, SO42-, Cl- and H2S were then measured. In addition, ex situ O2 microprofiles equipped with microsensors and in situ incubations using benthic chambers were performed to estimate the sediment uptake rates (O2, H2S, CH4). The overall dataset was used to feed the model. The preliminary results indicate 1) significant differences of biogeochemical processes between the different biological assemblages and 2) between the cold seeps and hydrothermal vents sites. Model outputs show the occurrence of AOM and sulfate reduction at all sites except the reference (i.e. bare sediment) confirming hence the chemosynthetic activity (OC production) within the specific biological assemblages (mats and Vesicomyid). AOM in bacterial mats was more active in hydrothermal vents than in cold-seeps. In addition, the results indicate strong sulfate reduction rates in Vesicomyids assemblages but with a clear mismatch between modeled and measured H2S concentrations in the sediment: such differences reflect the symbiosis chemosynthetic activity (i.e. the H2S consumption) within the organisms. This integrated model-data approach proves hence to be useful to infer the biogeochemical functioning of biological ecosystems. [1] Kallmeyer, J. & Boetius, A (2004): Applied and Environmental Microbiology, 70, 2, 1231-1233. [2] Biddle J. F. et al. (2012). ISME J. 6 1018-1031

Harvesting of Scenedesmus obliquus FSP-3 using dispersed ozone flotation.

PubMed

Cheng, Ya-Ling; Juang, Yu-Chuan; Liao, Guan-Yu; Tsai, Pei-Wen; Ho, Shih-Hsin; Yeh, Kuei-Ling; Chen, Chun-Yen; Chang, Jo-Shu; Liu, Jhy-Chern; Chen, Wen-Ming; Lee, Duu-Jong

2011-01-01

The Scenedesmus obliquus FSP-3, a species with excellent potential for CO(2) capture and lipid production, was harvested using dispersed ozone flotation. While air aeration does not, ozone produces effective solid-liquid separation through flotation. Ozone dose applied for sufficient algal flotation is similar to those used in practical drinking waterworks. The algae removal rate, surface charge, and hydrophobicity of algal cells, and fluorescence characteristics and proteins and polysaccharides contents of algogenic organic matter (AOM) were determined during ozonation. Proteins released from tightly bound AOM are essential to modifying the hydrophobicity of bubble surfaces for easy cell attachment and to forming a top froth layer for collecting floating cells. Humic substances in the suspension scavenge dosed ozone that adversely affects ozone flotation efficiency of algal cells. Copyright © 2010 Elsevier Ltd. All rights reserved.

External cavity quantum cascade lasers with ultra rapid acousto-optic tuning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyakh, A., E-mail: alyakh@pranalytica.com; Barron-Jimenez, R.; Dunayevskiy, I.

2015-04-06

We report operation of tunable external cavity quantum cascade lasers with emission wavelength controlled by an acousto-optic modulator (AOM). A long-wave infrared quantum cascade laser wavelength tuned from ∼8.5 μm to ∼9.8 μm when the AOM frequency was changed from ∼41MHz to ∼49 MHz. The laser delivered over 350 mW of average power at the center of the tuning curve in a linewidth of ∼4.7 cm{sup −1}. Measured wavelength switching time between any two wavelengths within the tuning range of the QCL was less than 1 μs. Spectral measurements of infrared absorption features of Freon demonstrated a capability of obtaining complete spectral data in less thanmore » 20 μs.« less

High-speed optical coherence tomography using fiberoptic acousto-optic phase modulation

NASA Astrophysics Data System (ADS)

Xie, Tuqiang; Wang, Zhenguo; Pan, Yingtian

2003-12-01

We report a new rapid-scanning optical delay device suitable for high-speed optical coherence tomography (OCT) in which an acousto-optic modulator (AOM) is used to independently modulate the Doppler frequency shift of the reference light beam for optical heterodyne detection. Experimental results show that the fluctuation of the measured Doppler frequency shift is less than +/-0.2% over 95% duty cycle of OCT imaging, thus allowing for enhanced signal-to-noise ratio of optical heterodyne detection. The increased Doppler frequency shift by AOM also permits complete envelop demodulation without the compromise of reducing axial resolution; if used with a resonant rapid-scanning optical delay, it will permit high-performance real-time OCT imaging. Potentially, this new rapid-scanning optical delay device will improve the performance of high-speed Doppler OCT techniques.

Vanillin-Ameliorated Development of Azoxymethane/Dextran Sodium Sulfate-Induced Murine Colorectal Cancer: The Involvement of Proteasome/Nuclear Factor-κB/Mitogen-Activated Protein Kinase Pathways.

PubMed

Li, Jung-Miao; Lee, Yu-Chen; Li, Chia-Cheng; Lo, Hsin-Yi; Chen, Feng-Yuan; Chen, Yi-Siou; Hsiang, Chien-Yun; Ho, Tin-Yun

2018-06-06

Vanillin is a natural dietary flavoring widely used in the food industry. Colorectal cancer (CRC) is one of the common malignancies in the world. Chronic intestinal inflammation is a risk factor for the development of CRC. We have previously found that vanillin improves and prevents colitis in mice. Here we evaluated the inhibitory activities of vanillin on a mouse model of colitis-induced CRC. Mice were challenged intraperitoneally with azoxymethane (AOM) and orally with dextran sodium sulfate (DSS). Various dosages of vanillin were orally administered for 13 consecutive weeks. Vanillin alleviated the development of tumors in AOM/DSS-induced mice. The total number of tumors in 100 mg/kg vanillin group was significantly reduced by 57.14 ± 7.67%, compared with sham group. Gene expression analysis showed that vanillin downregulated the expression levels of proteasome genes in colon tissues. Moreover, vanillin at 10 mM significantly suppressed proteasome activities in HCT-116 cells by 41.27 ± 0.41%. Furthermore, vanillin diminished the phosphorylation of mitogen-activated protein kinases (MAPKs) and reduced the number of p65-positive cells, proliferating cells, and granulocytes in colon tissues with statistical significance. In conclusion, our data suggested that vanillin was a bioactive compound that ameliorated the development of AOM/DSS-induced colon cancer in mice. Moreover, the amelioration of vanillin might be associated with the downregulation of proteasome, nuclear factor-κB, and MAPK pathways.

Enzymes involved in the anaerobic oxidation of n-alkanes: from methane to long-chain paraffins

PubMed Central

Callaghan, Amy V.

2013-01-01

Anaerobic microorganisms play key roles in the biogeochemical cycling of methane and non-methane alkanes. To date, there appear to be at least three proposed mechanisms of anaerobic methane oxidation (AOM). The first pathway is mediated by consortia of archaeal anaerobic methane oxidizers and sulfate-reducing bacteria (SRB) via “reverse methanogenesis” and is catalyzed by a homolog of methyl-coenzyme M reductase. The second pathway is also mediated by anaerobic methane oxidizers and SRB, wherein the archaeal members catalyze both methane oxidation and sulfate reduction and zero-valent sulfur is a key intermediate. The third AOM mechanism is a nitrite-dependent, “intra-aerobic” pathway described for the denitrifying bacterium, ‘Candidatus Methylomirabilis oxyfera.’ It is hypothesized that AOM proceeds via reduction of nitrite to nitric oxide, followed by the conversion of two nitric oxide molecules to dinitrogen and molecular oxygen. The latter can be used to functionalize the methane via a particulate methane monooxygenase. With respect to non-methane alkanes, there also appear to be novel mechanisms of activation. The most well-described pathway is the addition of non-methane alkanes across the double bond of fumarate to form alkyl-substituted succinates via the putative glycyl radical enzyme, alkylsuccinate synthase (also known as methylalkylsuccinate synthase). Other proposed mechanisms include anaerobic hydroxylation via ethylbenzene dehydrogenase-like enzymes and an “intra-aerobic” denitrification pathway similar to that described for ‘Methylomirabilis oxyfera.’ PMID:23717304

Chemopreventive and Antioxidant Effect of Polyphenol Free Spirulina maxima and Its Hydrolyzed Protein Content: Investigation on Azoxymethane Treated Mice.

PubMed

Martínez-Palma, Nikte Y; Dávila-Ortiz, Gloria; Jiménez-Martínez, Cristian; Madrigal-Bujaidar, Eduardo; Álvarez-González, Isela

2017-07-01

Spirulina maxima (Sm) is known to have nutritive value as well as a number of potentially useful biomedical properties. The initial purpose of this report was to evaluate the inhibitory effect of the alga (without its polyphenol content), on the induction of azoxymethane (AOM)-induced colon aberrant crypts (AC) in mouse. Besides, we hydrolyzed the protein content of such mixture. Our second aim was to determine the inhibitory potential of this last plant mixture on the AOM-induced colon AC in mouse. Moreover, we also determined the effect of the two indicated Sm samples on the oxidative damage caused by AOM in the colon and liver of treated mice. The experiment lasted 5 weeks. At the end, we registered the level of AC, nitric oxide, and the lipid and protein oxidation. Our results showed the following: (1) the carcinogen increased more than 18 times the amount of the AC found in the control group. (2) On the contrary, the two tested mixtures of Sm produced a significant reduction over this damage (about 45%). (3) The two tested Sm mixtures were generally able to reduce the oxidative stress markers although with variable effects which go from 59% to 100% with respect to the control mice. Therefore, the present report established that the tested Sm fractions have mouse colon anticarcinogenic potential, partially related with their antioxidant capacity. Our report also suggested the need to further evaluate specific Sm chemicals as chemopreventive agents.

Reliability and validity of functional health status and health-related quality of life questionnaires in children with recurrent acute otitis media

PubMed Central

Brouwer, Carole N. M.; Schilder, Anne G. M.; van Stel, Henk F.; Rovers, Maroeska M.; Veenhoven, Reinier H.; Grobbee, Diederick E.; Sanders, Elisabeth A. M.

2007-01-01

In this study the reliability and validity of generic and disease-specific questionnaires has been assessed focusing on responsiveness. This is part of a study on the effects of recurrent acute otitis media (rAOM) on functional health status (FHS) and health-related quality of life (HRQoL) in 383 children with rAOM participating in a randomized clinical trial. The following generic questionnaires were studied: 1. RAND general health rating index, 2. Functional Status Questionnaire (FSQ Generic and FSQ Specific), 3. TNO-AZL Infant Quality of Life (TAIQOL), and the following disease-specific questionnaires: 1. Otitis Media-6 (OM-6), 2. Numerical rating scales (NRS) for child and caregiver (NRS Child and NRS Caregiver), and 3. a new Family Functioning Questionnaire (FFQ). Reliability was good to excellent (Cronbach’s α range 0.80–0.90, intraclass correlation coefficient range 0.76–0.93). Moderate to strong correlations were found between the questionnaires as well as between questionnaires and relevant clinical indicators (r = 0.29–0.49), demonstrating construct validity. Discriminant validity for children with few versus frequent episodes of acute otitis media per year was good for most questionnaires (P < 0.004) but poor for the otitis media-related subscales of the TAIQOL (P = 0.10–0.97) and both NRS (P = 0.22 and 0.48). Except for the TAIQOL subscales, change scores were significant (P < 0.003) for generic and disease-specific questionnaires. Effect sizes were somewhat higher for disease-specific compared to generic questionnaires (0.55–0.95 versus 0.32–0.60) except for the TAIQOL subscales, which showed very poor sensitivity to change. Anchor-based methods resulted in a somewhat larger range of estimates of MCID than distribution-based methods. Combining distribution-based and anchor-based methods resulted in similar ranges for the minimally clinical important differences for generic and disease-specific questionnaires: 2–15 points on a 0–100 scale. Apart from the generic TAIQOL subscales, both generic and disease-specific questionnaires used in this study showed good psychometric qualities and responsiveness for use in clinical studies on children with rAOM. PMID:17668290

Comparison of direct-plating and broth-enrichment culture methods for detection of potential bacterial pathogens in respiratory secretions.

PubMed

Kaur, Ravinder; Wischmeyer, Jareth; Morris, Matthew; Pichichero, Michael E

2017-11-01

We compared the recovery of potential respiratory bacterial pathogens and normal flora from nasopharyngeal specimens collected from children during health and at the onset of acute otitis media (AOM) by selective direct-plating and overnight broth-enrichment. Overall, 3442 nasal wash (NW) samples collected from young children were analysed from a 10-year prospective study. NWs were cultured by (1) direct-plating to TSAII/5 % sheep blood agar and chocolate agar plates and (2) overnight broth-enrichment in BacT/ALERT SA-broth followed by plating. Standard microbiology techniques were applied to identify three dominant respiratory bacterial pathogens: Streptococcus pneumoniae (Spn), Haemophilus influenzae (Hflu) and Moraxella catarrhalis (Mcat) as well as two common nasal flora, Staphylococcus aureus (SA) and alpha-haemolytic Streptococci (AHS).Results/Key findings. Direct-plating of NW resulted in isolation of Spn from 37.8 %, Hflu from 13.6 % and Mcat from 33.2 % of samples. In comparison, overnight broth-enrichment isolated fewer Spn (30.1 %), Hflu (6.2 %) and Mcat (16.2 %) (P<0.001-0.0001). Broth-enrichment resulted in significant increased isolation of SA (6.0 %) and AHS (30.1 %) (P<0.0001). Competition between bacterial species in broth when both species were detected by direct-plating was assessed, and it was found that SA and AHS out-competed other species during broth-enrichment when samples were collected from healthy children but not during AOM. In middle ear fluids (MEF) at the onset of AOM, broth-enrichment resulted in higher recovery of Spn (+10.4 %, P<0.001), Hflu (+4.4 %, P=0.39) and Mcat (+13.5 %, <0.001). Broth-enrichment significantly reduces the accurate detection of bacterial respiratory pathogens and increases identification of SA and AHS in NW. Broth-enrichment improves detection of bacterial respiratory pathogens in MEF samples.

Identification, visualization, and sorting of translationally active microbial consortia from deep-sea methane seeps

NASA Astrophysics Data System (ADS)

Hatzenpichler, R.; Connon, S. A.; Goudeau, D.; Malmstrom, R.; Woyke, T.; Orphan, V. J.

2015-12-01

Within the past few years, great progress has been made in tapping the genomes of individual cells separated from environmental samples. Unfortunately, however, most often these efforts have been target blind, as they did not pre-select for taxa of interest or focus on metabolically active cells that could be considered key species of the system at the time. This problem is particularly pronounced in low-turnover systems such as deep sea sediments. In an effort to tap the genetic potential hidden within functionally active cells, we have recently developed an approach for the in situ fluorescent tracking of protein synthesis in uncultured cells via bioorthogonal non-canonical amino acid-tagging (BONCAT). This technique depends on the incorporation of synthetic amino acids that carry chemically modifiable tags into newly made proteins, which later can be visualized via click chemistry-mediated fluorescence-labeling. BONCAT is thus able to specifically target proteins that have been expressed in reaction to an experimental condition. We are particularly interested in using BONCAT to understand the functional potential of slow-growing syntrophic consortia of anaerobic methanotrophic archaea and sulfate-reducing bacteria which together catalyze the anaerobic oxidation of methane (AOM) in marine methane seeps. In order to specifically target consortia that are active under varying environmental regimes, we are studying different subpopulations of these inter-domain consortia via a combination of BONCAT with rRNA-targeted FISH. We then couple the BONCAT-enabled staining of active consortia with their separation from inactive members of the community via fluorescence-activated cell-sorting (FACS) and metagenomic sequencing of individual consortia. Using this approach, we were able to identify previously unrecognized AOM-partnerships. By comparing the mini-metagenomes obtained from individual consortia with each other we are starting to gain a more hollistic understanding of the genetic similarities and niche-determining characteristics of a range of functional and taxonomic clades of AOM-consortia.

Isoliquiritigenin, a flavonoid from licorice, blocks M2 macrophage polarization in colitis-associated tumorigenesis through downregulating PGE{sub 2} and IL-6

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Haixia; Zhang, Xinhua; Chen, Xuewei

M2 macrophage polarization is implicated in colorectal cancer development. Isoliquiritigenin (ISL), a flavonoid from licorice, has been reported to prevent azoxymethane (AOM) induced colon carcinogenesis in animal models. Here, in a mouse model of colitis-associated tumorigenesis induced by AOM/dextran sodium sulfate (DSS), we investigated the chemopreventive effects of ISL and its mechanisms of action. Mice were treated with AOM/DSS and randomized to receive either vehicle or ISL (3, 15 and 75 mg/kg). Tumor load, histology, immunohistochemistry, and gene and protein expressions were determined. Intragastric administration of ISL for 12 weeks significantly decreased colon cancer incidence, multiplicity and tumor size bymore » 60%, 55.4% and 42.6%, respectively. Moreover, ISL inhibited M2 macrophage polarization. Such changes were accompanied by downregulation of PGE{sub 2} and IL-6 signaling. Importantly, depletion of macrophages by clodronate (Clod) or zoledronic acid (ZA) reversed the effects of ISL. In parallel, in vitro studies also demonstrated that ISL limited the M2 polarization of RAW264.7 cells and mouse peritoneal macrophages with concomitant inactivation of PGE{sub 2}/PPARδ and IL-6/STAT3 signaling. Conversely, exogenous addition of PGE{sub 2} or IL-6, or overexpression of constitutively active STAT3 reversed ISL-mediated inhibition of M2 macrophage polarization. In summary, dietary flavonoid ISL effectively inhibits colitis-associated tumorigenesis through hampering M2 macrophage polarization mediated by the interplay between PGE{sub 2} and IL-6. Thus, inhibition of M2 macrophage polarization is likely to represent a promising strategy for chemoprevention of colorectal cancer. - Highlights: • Isoliquiritigenin (ISL) prevents colitis-associated tumorigenesis. • ISL inhibits M2 macrophage polarization in vivo and in vitro. • ISL inhibits PGE{sub 2} and IL-6 signaling in colitis-associated tumorigenesis. • ISL may be an attractive candidate agent for chemoprevention of colorectal cancer.« less

Plum polyphenols inhibit colorectal aberrant crypt foci formation in rats: potential role of the miR-143/protein kinase B/mammalian target of rapamycin axis.

PubMed

Banerjee, Nivedita; Kim, Hyemee; Talcott, Stephen T; Turner, Nancy D; Byrne, David H; Mertens-Talcott, Susanne U

2016-10-01

The nutritional prevention of aberrant crypt foci by polyphenols may be a crucial step to dietary cancer prevention. The objective of this study was to determine the underlying mechanisms that contribute to the anti-inflammatory and antitumorigenic properties of plum (Prunus salicina L.) polyphenols, including chlorogenic acid and neochlorogenic acid, in azoxymethane (AOM)-treated rats. The hypothesis was that plum polyphenolics suppress AOM-induced aberrant crypt foci formation through alterations in the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and relative micro-RNA expressions. Sprague-Dawley rats (n=10/group) received plum beverage (1346mg gallic acid equivalents/L) or a control beverage ad libitum for 10 weeks with subcutaneous injections of AOM (15mg/kg) at weeks 2 and 3. Results show that the consumption of the plum beverage decreased the number of dysplastic aberrant crypt foci by 48% (P<.05) and lowered proliferation of mucosal cells by 24% (P<.05). The plum beverage decreased the activity of glutathione peroxidase, superoxide dismutase, and catalase in mucosal scrapings, as well as the superoxide dismutase activity in serum. The results were accompanied by a down-regulation of proinflammatory enzymes nuclear factor κB, nitric oxide synthase, cyclooxygenase-2, and vascular cell adhesion molecule 1 messenger RNA. Plum inhibited the expression of AKT and mTOR messenger RNA, phosphorylated AKT, mTOR, and hypoxia-inducible factor-1α protein levels, and the ratio of the phosphorylated/total protein expression of mTOR. Also, the plum beverage increased the expression of miR-143, which is involved in the regulation of AKT. These results suggest that plum polyphenols may exhibit a chemopreventive potential against colon carcinogenesis by impacting the AKT/mTOR pathway and miR-143. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of shallow sediment methane cycling in a pockmark field on the Chatham Rise, New Zealand

NASA Astrophysics Data System (ADS)

Coffin, R. B.; Rose, P. S.; Klaucke, I.; Bialas, J.; Pecher, I. A.; Gorman, A. R.

2014-12-01

Seismic studies have identified an extensive field (>20,000 km2) of seafloor depressions, or pockmarks, on the southwestern flank of the Chatham Rise, New Zealand. It has been suggested that these pockmarks result from gas hydrate dissociation linked to sea-level changes during glacial-interglacial cycles. Gas hydrates are predominately composed of methane (CH4), a potent greenhouse gas. Surface sediment cores (~ 8 m) were collected from the pockmark field on the Chatham Rise during a research cruise in February 2013 to evaluate the association of the features with CH4 releases. A suite of geochemical parameters are interpreted to determine the methane contribution to solid phase sediment and pore water. The upward flux of CH4 in sediments is often quantified using pore water sulfate (SO42-) profiles, assuming steady-state consumption of SO42- and CH4 by anaerobic oxidation of methane (AOM): CH4 + SO42- → HCO3- + HS- + H2O. This reaction is one of the primary controls on CH4 distributions in sediments. This work will present pore water SO42-, sulfide (HS-) and chloride (Cl-) depth profiles in sediment collected from the pockmark field. Theoretical SO42- distributions in the absence of AOM are compared to observed SO42- profiles as a preliminary assessment of the influence of CH4 on sediment geochemistry in and around the seafloor depressions. In addition isotopically-light CH4 is incorporated into sediment carbon pools via AOM and subsequent CO2 fixation. Stable carbon isotope distributions in the organic and inorganic carbon pools are presented to determine the influence of CH4 in sediments in the vicinty of the pockmarks. Collectively, the geochemical data are used to assess the role of gas hydate dissociation in pockmark formation on the Chatham Rise. Despite sesimic data interpretation in this region there is no modern day contribution of CH4 to shallow sediment carbon cycling and data are presented to assess paleogeochemical methane cycling.

Identification of flat dysplastic aberrant crypt foci in the colon of azoxymethane-treated A/J mice.

PubMed

Paulsen, Jan Erik; Knutsen, Helle; Ølstørn, Hege Benedikte; Løberg, Else Marit; Alexander, Jan

2006-02-01

The role of aberrant crypt foci (ACF) as preneoplastic lesions in colon carcinogenesis is not clear. In Min/+ mice and their wild-type littermates treated with azoxymethane (AOM), we previously identified a subgroup of flat ACF that seem more immediate precursors of tumors than the classical elevated ACF. In the present study, we identified a similar subgroup of flat ACF in AOM-treated A/J mice and compared them with nascent tumors and classical elevated ACF. At week 1 and 2 after birth, A/J mice were injected subcutaneously with AOM (10 mg/kg bw/injection). At weeks 7-14, we examined the luminal surface of unsectioned colon preparations stained with methylene blue in the inverse light microscope. The lesions were also examined by histopathology and immunohistochemistry. Surface examination revealed flat ACF, classical elevated ACF and nascent tumors. Since flat ACF were not observed as elevated structures, their bright blue appearance and compressed pit pattern of crypt openings seen with transillumination were used as criteria for their identification. Flat ACF and nascent tumors displayed a uniform picture of severe dysplasia, compressed pit pattern, overexpression of cytoplasmic/nuclear beta-catenin and nuclear overexpression of cyclin D1. Apparently, flat ACF and tumors represented the same type of dysplastic lesions at different stages of crypt multiplication. In contrast, classical elevated ACF did not seem to be as clearly related to tumorigenesis. They infrequently (1/20) possessed severe dysplasia, overexpression of cytoplasmic/nuclear beta-catenin, or nuclear overexpression of cyclin D1, and they did not have compressed crypt openings. Furthermore, flat ACF grew significantly faster than classical elevated ACF. In conclusion, our data indicate a development from flat ACF to adenoma characterized by aberrant activation of the Wnt signaling pathway and fast crypt multiplication. Classical elevated ACF do not seem to be as closely related to tumorigenesis. Copyright 2005 Wiley-Liss, Inc.

A Metagenomics-Based Metabolic Model of Nitrate-Dependent Anaerobic Oxidation of Methane by Methanoperedens-Like Archaea

PubMed Central

Arshad, Arslan; Speth, Daan R.; de Graaf, Rob M.; Op den Camp, Huub J. M.; Jetten, Mike S. M.; Welte, Cornelia U.

2015-01-01

Methane oxidation is an important process to mitigate the emission of the greenhouse gas methane and further exacerbating of climate forcing. Both aerobic and anaerobic microorganisms have been reported to catalyze methane oxidation with only a few possible electron acceptors. Recently, new microorganisms were identified that could couple the oxidation of methane to nitrate or nitrite reduction. Here we investigated such an enrichment culture at the (meta) genomic level to establish a metabolic model of nitrate-driven anaerobic oxidation of methane (nitrate-AOM). Nitrate-AOM is catalyzed by an archaeon closely related to (reverse) methanogens that belongs to the ANME-2d clade, tentatively named Methanoperedens nitroreducens. Methane may be activated by methyl-CoM reductase and subsequently undergo full oxidation to carbon dioxide via reverse methanogenesis. All enzymes of this pathway were present and expressed in the investigated culture. The genome of the archaeal enrichment culture encoded a variety of enzymes involved in an electron transport chain similar to those found in Methanosarcina species with additional features not previously found in methane-converting archaea. Nitrate reduction to nitrite seems to be located in the pseudoperiplasm and may be catalyzed by an unusual Nar-like protein complex. A small part of the resulting nitrite is reduced to ammonium which may be catalyzed by a Nrf-type nitrite reductase. One of the key questions is how electrons from cytoplasmically located reverse methanogenesis reach the nitrate reductase in the pseudoperiplasm. Electron transport in M. nitroreducens probably involves cofactor F420 in the cytoplasm, quinones in the cytoplasmic membrane and cytochrome c in the pseudoperiplasm. The membrane-bound electron transport chain includes F420H2 dehydrogenase and an unusual Rieske/cytochrome b complex. Based on genome and transcriptome studies a tentative model of how central energy metabolism of nitrate-AOM could work is presented and discussed. PMID:26733968

Authigenic carbonate precipitates from the NE Black Sea: a mineralogical, geochemical, and lipid biomarker study

NASA Astrophysics Data System (ADS)

Bahr, A.; Pape, T.; Bohrmann, G.; Mazzini, A.; Haeckel, M.; Reitz, A.; Ivanov, M.

2009-04-01

Carbonate precipitates recovered from 2,000 m water depth at the Dolgovskoy Mound (Shatsky Ridge, north eastern Black Sea) were studied using mineralogical, geochemical and lipid biomarker analyses. The carbonates differ in shape from simple pavements to cavernous structures with thick microbial mats attached to their lower side and within cavities. Low δ13C values measured on carbonates (-41 to -32‰ V-PDB) and extracted lipid biomarkers indicate that anaerobic oxidation of methane (AOM) played a crucial role in precipitating these carbonates. The internal structure of the carbonates is dominated by finely laminated coccolith ooze and homogeneous clay layers, both cemented by micritic high-magnesium calcite (HMC), and pure, botryoidal, yellowish low-magnesium calcite (LMC) grown in direct contact to microbial mats. δ18O measurements suggest that the authigenic HMC precipitated in equilibrium with the Black Sea bottom water while the yellowish LMC rims have been growing in slightly 18O-depleted interstitial water. Although precipitated under significantly different environmental conditions, especially with respect to methane availability, all analysed carbonate samples show lipid patterns that are typical for ANME-1 dominated AOM consortia, in the case of the HMC samples with significant contributions of allochthonous components of marine and terrestrial origin, reflecting the hemipelagic nature of the primary sediment.

An Angular Overlap Model for Cu(II) Ion in the AMOEBA Polarizable Force Field

PubMed Central

Xiang, Jin Yu; Ponder, Jay W.

2014-01-01

An extensible polarizable force field for transition metal ion was developed based on AMOEBA and the angular overlap model (AOM) with consistent treatment of electrostatics for all atoms. Parameters were obtained by fitting molecular mechanics (MM) energies to various ab initio gas-phase calculations. The results of parameterization were presented for copper (II) ion ligated to water and model fragments of amino acid residues involved in the copper binding sites of type 1 copper proteins. Molecular dynamics (MD) simulations were performed on aqueous copper (II) ion at various temperatures, as well as plastocyanin (1AG6) and azurin (1DYZ). Results demonstrated that the AMOEBA-AOM significantly improves the accuracy of classical MM in a number of test cases when compared to ab initio calculations. The Jahn-Teller distortion for hexa-aqua copper (II) complex was handled automatically without specifically designating axial and in-plane ligands. Analyses of MD trajectories resulted in a 6-coordination first solvation shell for aqueous copper (II) ion and a 1.8ns average residence time of water molecules. The ensemble average geometries of 1AG6 and 1DYZ copper binding sites were in general agreement with X-ray and previous computational studies. PMID:25045338

Complement activation promotes colitis-associated carcinogenesis through activating intestinal IL-1β/IL-17A axis.

PubMed

Ning, C; Li, Y-Y; Wang, Y; Han, G-C; Wang, R-X; Xiao, H; Li, X-Y; Hou, C-M; Ma, Y-F; Sheng, D-S; Shen, B-F; Feng, J-N; Guo, R-F; Li, Y; Chen, G-J

2015-11-01

Colitis-associated colorectal cancer (CAC) is the most serious complication of inflammatory bowel disease (IBD). Excessive complement activation has been shown to be involved in the pathogenesis of IBD. However, its role in the development of CAC is largely unknown. Here, using a CAC model induced by combined administration of azoxymethane (AOM) and dextran sulfate sodium (DSS), we demonstrated that complement activation was required for CAC pathogenesis. Deficiency in key components of complement (e.g., C3, C5, or C5a receptor) rendered tumor repression in mice subjected to AOM/DSS. Mechanistic investigation revealed that complement ablation dramatically reduced proinflammatory cytokine interleukin (IL)-1β levels in the colonic tissues that was mainly produced by infiltrating neutrophils. IL-1β promoted colon carcinogenesis by eliciting IL-17 response in intestinal myeloid cells. Furthermore, complement-activation product C5a represented a potent inducer for IL-1β in neutrophil, accounting for downregulation of IL-1β levels in the employed complement-deficient mice. Overall, our study proposes a protumorigenic role of complement in inflammation-related colorectal cancer and that the therapeutic strategies targeting complement may be beneficial for the treatment of CAC in clinic.

Current concepts in the pathogenesis and treatment of chronic suppurative otitis media

PubMed Central

Mittal, Rahul; Lisi, Christopher V.; Gerring, Robert; Mittal, Jeenu; Mathee, Kalai; Narasimhan, Giri; Azad, Rajeev K.; Yao, Qi; Grati, M'hamed; Yan, Denise; Eshraghi, Adrien A.; Angeli, Simon I.; Telischi, Fred F.

2015-01-01

Otitis media (OM) is an inflammation of the middle ear associated with infection. Despite appropriate therapy, acute OM (AOM) can progress to chronic suppurative OM (CSOM) associated with ear drum perforation and purulent discharge. The effusion prevents the middle ear ossicles from properly relaying sound vibrations from the ear drum to the oval window of the inner ear, causing conductive hearing loss. In addition, the inflammatory mediators generated during CSOM can penetrate into the inner ear through the round window. This can cause the loss of hair cells in the cochlea, leading to sensorineural hearing loss. Pseudomonas aeruginosa and Staphylococcus aureus are the most predominant pathogens that cause CSOM. Although the pathogenesis of AOM is well studied, very limited research is available in relation to CSOM. With the emergence of antibiotic resistance as well as the ototoxicity of antibiotics and the potential risks of surgery, there is an urgent need to develop effective therapeutic strategies against CSOM. This warrants understanding the role of host immunity in CSOM and how the bacteria evade these potent immune responses. Understanding the molecular mechanisms leading to CSOM will help in designing novel treatment modalities against the disease and hence preventing the hearing loss. PMID:26248613

Comparison of mean climate trends in the Northern Hemisphere between National Centers for Environmental Prediction and two atmosphere-ocean model forced runs

NASA Astrophysics Data System (ADS)

Lucarini, Valerio; Russell, Gary L.

2002-08-01

Results are presented for two greenhouse gas experiments of the Goddard Institute for Space Studies atmosphere-ocean model (AOM). The computed trends of surface pressure; surface temperature; 850, 500, and 200 mbar geopotential heights; and related temperatures of the model for the time frame 1960-2000 are compared with those obtained from the National Centers for Enviromental Prediction (NCEP) observations. The domain of interest is the Northern Hemisphere because of the higher reliability of both the model results and the observations. A spatial correlation analysis and a mean value comparison are performed, showing good agreement in terms of statistical significance for most of the variables considered in the winter and annual means. However, the 850 mbar temperature trends do not show significant positive correlation, and the surface pressure and 850 mbar geopotential height mean trends confidence intervals do not overlap. A brief general discussion about the statistics of trend detection is presented. The accuracy that this AOM has in describing the regional and NH mean climate trends inferred from NCEP through the atmosphere suggests that it may be reliable in forecasting future climate changes.

Development of New Elastomers and Elastic Nanocomposites from Plant Oils

NASA Astrophysics Data System (ADS)

Zhu, Lin; Wool, Richard

2006-03-01

Economic and environmental concerns lead to the development of new polymers from renewable resources. In this research, new elastomers were synthesized from plant oil based resins. Acrylated oleic methyl ester (AOME), synthesized from high oleic triglycerides, can readily undergo free radical polymerization and form a linear polymer. To achieve the elastic properties, different strategies have been developed to generate an elastic network and control the crosslink density. The elastomers are reinforced by nanoclays. The intercalated state has a network structure similar to thermoplastic elastomers in which the hard segments aggregate to give ordered crystalline domains. The selected organically modified clay and AOME matrix have similar solubility parameters, therefore intercalation of the monomer/polymer into the clay layers occurs and the nano-scale multilayered structure is stable. In situ intercalation and solution intercalation were used to prepare the elastic nanocomposites. Dramatic improvement in mechanical properties was observed. Changes of tensile strength, strain, Young's modulus and fracture energy were related to the clay concentration. The fracture surface was studied to further understand clay effects on the mechanical properties. Self-Healing of the intercalated nanobeams, thermal stability, biocompatibility and biodegradability of this new elastomer were also explored.

Age-related differential responses to curcumin-induced apoptosis during the initiation of colon cancer in rats.

PubMed

Kwon, Youngjoo; Magnuson, Bernadene A

2009-02-01

Curcumin is a widely-used dietary supplement and a chemopreventive agent for various cancers. Pre-clinical chemopreventive studies rarely consider the effect of aging. We previously reported that unlike young animals, curcumin is ineffective in middle-aged rats for colon chemoprevention. This study investigated whether resistance to apoptosis during cancer initiation contributes to this age-dependent effect. Young, middle-aged, and old F344 rats were fed either curcumin (0.6%) or control diet. Colonic apoptosis was evaluated 0, 8, and 16 h after azoxymethane (AOM) injection. Colonic Hsp70 mRNA levels, caspase-9 activity, cell proliferation, and crypt morphology were measured. In AOM-treated rats, only middle-aged rats were resistant to curcumin-induced apoptosis whereas cell proliferation was reduced by curcumin in all ages. Curcumin-induced apoptosis was mediated by caspase-9 in young but not older rats. Transcriptional Hsp70 expression was induced in only young rats and was suppressed by curcumin. Therefore, the age-related difference in curcumin chemoprevention is due to a differential response in induction of apoptosis. The mitochondria-dependent pathway seems to mediate curcumin-induced apoptosis in young but not older animals. Hsp70 expression was not related with resistance to curcumin-induced apoptosis. Understanding age-related differences in the apoptotic response may lead to improved translation from pre-clinical animal studies to humans.

Projected future climate change and Baltic Sea ecosystem management.

PubMed

Andersson, Agneta; Meier, H E Markus; Ripszam, Matyas; Rowe, Owen; Wikner, Johan; Haglund, Peter; Eilola, Kari; Legrand, Catherine; Figueroa, Daniela; Paczkowska, Joanna; Lindehoff, Elin; Tysklind, Mats; Elmgren, Ragnar

2015-06-01

Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2-4 °C warming and 50-80 % decrease in ice cover by 2100. Precipitation may increase ~30 % in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants and decreased salinity. Coupled physical-biogeochemical models indicate that, in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, thus promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favored by AOM, while phytoplankton production may be reduced. Extra trophic levels in the food web may increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider the effects of climate change on the ecosystem dynamics and functions, as well as the effects of anthropogenic nutrient and pollutant load. Monitoring should have a holistic approach, encompassing both autotrophic (phytoplankton) and heterotrophic (e.g., bacterial) processes.

Macroscopic biofilms in fracture-dominated sediment that anaerobically oxidize methane

USGS Publications Warehouse

Briggs, B.R.; Pohlman, J.W.; Torres, M.; Riedel, M.; Brodie, E.L.; Colwell, F.S.

2011-01-01

Methane release from seafloor sediments is moderated, in part, by the anaerobic oxidation of methane (AOM) performed by consortia of archaea and bacteria. These consortia occur as isolated cells and aggregates within the sulfate-methane transition (SMT) of diffusion and seep-dominant environments. Here we report on a new SMT setting where the AOM consortium occurs as macroscopic pink to orange biofilms within subseafloor fractures. Biofilm samples recovered from the Indian and northeast Pacific Oceans had a cellular abundance of 10 7 to 10 8 cells cm -3. This cell density is 2 to 3 orders of magnitude greater than that in the surrounding sediments. Sequencing of bacterial 16S rRNA genes indicated that the bacterial component is dominated by Deltaproteobacteria, candidate division WS3, and Chloroflexi, representing 46%, 15%, and 10% of clones, respectively. In addition, major archaeal taxa found in the biofilm were related to the ANME-1 clade, Thermoplasmatales, and Desulfurococcales, representing 73%, 11%, and 10% of archaeal clones, respectively. The sequences of all major taxa were similar to sequences previously reported from cold seep environments. PhyloChip microarray analysis detected all bacterial phyla identified by the clone library plus an additional 44 phyla. However, sequencing detected more archaea than the PhyloChip within the phyla of Methanosarcinales and Desulfurococcales. The stable carbon isotope composition of the biofilm from the SMT (-35 to-43%) suggests that the production of the biofilm is associated with AOM. These biofilms are a novel, but apparently widespread, aggregation of cells represented by the ANME-1 clade that occur in methane-rich marine sediments. ?? 2011, American Society for Microbiology.

A Flexible Master Oscillator for a Thomson Scattering Pulse-Burst Laser System

NASA Astrophysics Data System (ADS)

den Hartog, D. J.; Young, W. C.

2015-11-01

A new master oscillator will be installed in the pulse-burst laser system used for high-rep-rate Thomson scattering on the MST experiment. This new master oscillator will enable pulse repetition rates up to 1 MHz, with the ability to program a burst of pulses with arbitrary and varying time separation between each pulse. In addition, the energy of each master oscillator pulse can be adjusted to compensate for gain variations in the power amplifier section of the laser system. This flexibility is accomplished by chopping a CW laser source with a high-bandwidth acousto-optic modulator (AOM). The laser source is a 1064 nm diode-pumped solid-state laser with continuous output power variable from 100 to 500 mW. The 2 mm diameter polarized beam is focused into the gallium phosphide crystal of the AOM, which deflects the beam by approximately 60 mrad. Beam deflection is controlled by a simple digital input pulse, and is capable of producing laser pulses of less than 20 ns width at repetition rates much greater than 1 MHz. These pulses from the output of the AOM will be collimated and propagated into the laser amplifier system, where they will be amplified to ~ 2 J/pulse and injected into the MST plasma. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Award Number DE-FC02-05ER54814, and by the National Science Foundation under Award Number PHY-0821899.

Chemopreventive and Antioxidant Effect of Polyphenol Free Spirulina maxima and Its Hydrolyzed Protein Content: Investigation on Azoxymethane Treated Mice

PubMed Central

Martínez-Palma, Nikte Y.; Dávila-Ortiz, Gloria; Jiménez-Martínez, Cristian; Madrigal-Bujaidar, Eduardo; Álvarez-González, Isela

2017-01-01

Background: Spirulina maxima (Sm) is known to have nutritive value as well as a number of potentially useful biomedical properties. Objectives: The initial purpose of this report was to evaluate the inhibitory effect of the alga (without its polyphenol content), on the induction of azoxymethane (AOM)-induced colon aberrant crypts (AC) in mouse. Besides, we hydrolyzed the protein content of such mixture. Our second aim was to determine the inhibitory potential of this last plant mixture on the AOM-induced colon AC in mouse. Moreover, we also determined the effect of the two indicated Sm samples on the oxidative damage caused by AOM in the colon and liver of treated mice. Materials and Methods: The experiment lasted 5 weeks. At the end, we registered the level of AC, nitric oxide, and the lipid and protein oxidation. Results: Our results showed the following: (1) the carcinogen increased more than 18 times the amount of the AC found in the control group. (2) On the contrary, the two tested mixtures of Sm produced a significant reduction over this damage (about 45%). (3) The two tested Sm mixtures were generally able to reduce the oxidative stress markers although with variable effects which go from 59% to 100% with respect to the control mice. Conclusion: Therefore, the present report established that the tested Sm fractions have mouse colon anticarcinogenic potential, partially related with their antioxidant capacity. Our report also suggested the need to further evaluate specific Sm chemicals as chemopreventive agents. PMID:28808375

15-Hydroxyprostaglandin dehydrogenase is an in vivo suppressor of colon tumorigenesis.

PubMed

Myung, Seung-Jae; Rerko, Ronald M; Yan, Min; Platzer, Petra; Guda, Kishore; Dotson, Angela; Lawrence, Earl; Dannenberg, Andrew J; Lovgren, Alysia Kern; Luo, Guangbin; Pretlow, Theresa P; Newman, Robert A; Willis, Joseph; Dawson, Dawn; Markowitz, Sanford D

2006-08-08

15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is a prostaglandin-degrading enzyme that is highly expressed in normal colon mucosa but is ubiquitously lost in human colon cancers. Herein, we demonstrate that 15-PGDH is active in vivo as a highly potent suppressor of colon neoplasia development and acts in the colon as a required physiologic antagonist of the prostaglandin-synthesizing activity of the cyclooxygenase 2 (COX-2) oncogene. We first show that 15-PGDH gene knockout induces a marked 7.6-fold increase in colon tumors arising in the Min (multiple intestinal neoplasia) mouse model. Furthermore, 15-PGDH gene knockout abrogates the normal resistance of C57BL/6J mice to colon tumor induction by the carcinogen azoxymethane (AOM), conferring susceptibility to AOM-induced adenomas and carcinomas in situ. Susceptibility to AOM-induced tumorigenesis is mediated by a marked induction of dysplasia, proliferation, and cyclin D1 expression throughout microscopic aberrant crypt foci arising in 15-PGDH null colons and is concomitant with a doubling of prostaglandin E(2) in 15-PGDH null colonic mucosa. A parallel role for 15-PGDH loss in promoting the earliest steps of colon neoplasia in humans is supported by our finding of a universal loss of 15-PGDH expression in microscopic colon adenomas recovered from patients with familial adenomatous polyposis, including adenomas as small as a single crypt. These models thus delineate the in vivo significance of 15-PGDH-mediated negative regulation of the COX-2 pathway and moreover reveal the particular importance of 15-PGDH in opposing the neoplastic progression of colonic aberrant crypt foci.

Fracture experience among participants from the FROCAT study: what thresholding is appropriate using the FRAX tool?

PubMed

Azagra, R; Zwart, M; Aguyé, A; Martín-Sánchez, J C; Casado, E; Díaz-Herrera, M A; Moriña, D; Cooper, C; Díez-Pérez, A; Dennison, E M

2016-01-01

To perform an external validation of FRAX algorithm thresholds for reporting level of risk of fracture in Spanish women (low < 5%; intermediate ≥ 5% and < 7.5%; high ≥ 7.5%) taken from a prospective cohort "FRIDEX". A retrospective study of 1090 women aged ≥ 40 and ≤ 90 years old obtained from the general population (FROCAT cohort). FRAX was calculated with data registered in 2002. All fractures were validated in 2012. Sensitivity analysis was performed. When analyzing the cohort (884) excluding current or past anti osteoporotic medication (AOM), using our nominated thresholds, among the 621 (70.2%) women at low risk of fracture, 5.2% [CI95%: 3.4-7.6] sustained a fragility fracture; among the 99 at intermediate risk, 12.1% [6.4-20.2]; and among the 164 defined as high risk, 15.9% [10.6-24.2]. Sensitivity analysis against model risk stratification FRIDEX of FRAX Spain shows no significant difference. By including 206 women with AOM, the sensitivity analysis shows no difference in the group of intermediate and high risk and minimal differences in the low risk group. Our findings support and validate the use of FRIDEX thresholds of FRAX when discussing the risk of fracture and the initiation of therapy with patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Chemopreventive effect of dietary glutamine on colitis-associated colon tumorigenesis in mice.

PubMed

Tian, Yun; Wang, Keming; Wang, Zhaoxia; Li, Nan; Ji, Guozhong

2013-07-01

Chronic colonic inflammation is a known risk factor for colorectal cancer (CRC). Glutamine (GLN) supplementation has shown its anti-inflammation benefit in experimental colitis. Whether GLN is effective in preventing colon carcinogenesis remains to be investigated. The chemopreventive activity of GLN was evaluated in the mouse model of dextran sulfate sodium (DSS)/azoxymethane (AOM)-induced colitis-associated CRC in this study. Mice were treated with DSS/AOM and randomized to receive either a control diet or GLN-enriched diet intermittently of the study. The disease activity index was evaluated weekly. On day 80 of the experiment, the entire colon and rectum were processed for histopathologic examination and further evaluation. Pro-inflammatory mediators and cytokines were measured by enzyme-linked immunosorbent assay, real-time-PCR and western blot analysis. Here, we show that after GLN-enriched diet, the colitis presented a statistical improvement and tumors burden decreased significantly. This was accompanied by lower activity of nuclear factor-κB (NF-κB), decreased expression of cyclooxygenase-2 and inducible nitric oxide synthase, lower expression of cytokines and chemokines as well as reduced proliferation and induced apoptosis in the colons of colitis-associated CRC mice. Our data demonstrate the protective/preventive effect of GLN in the progression of colitis-associated CRC, which was correlated with a dampening of inflammation and NF-κB activity and with a decrease of inflammatory protein overexpression.

Dietary Ziziphus jujuba Fruit Influence on Aberrant Crypt Formation and Blood Cells in Colitis-Associated Colorectal Cancer in Mice.

PubMed

Periasamy, Srinivasan; Liu, Chung-Teng; Wu, Wang-Hung; Chien, Se-Ping; Liu, Ming-Yie

2015-01-01

Ziziphus jujuba (ZJ) fruit is rich in bioactive functional components such as polysaccharides, triterpenoid acid, flavonoids and oleamide. It has been commonly used in the treatment of various diseases including diabetes, digestive disorders, diarrhea, skin infections, liver and urinary complaints. However, dietary effects with regard to chemoprevention of colon cancer have not been studied. The present study was performed to evaluate the protective effects of dietary ZJ against colitis-associated colon carcinogenesis in azoxymethane (AOM)-dextran sodium sulphate (DSS)-treated mice. AOM was injected (10 mg/kg b.wt., i.p.) and three cycles of 2% DSS in drinking water for 7 days with 14 days of normal drinking water in-between were administered to induce colitis-associated colon cancer. ZJ fruit was supplemented into feed at levels of 5 and 10%. Dietary ZJ significantly attenuated aberrant crypt foci (ACF) formation and also decreased the progression of hyperplasia to dysplasia. In addition, it significantly reduced circulating white blood cells, lymphocytes, neutrophils, monocytes, eosinophils, basophils and platelets compared to colon cancer mice. We conclude that ZJ supplementation may delay the progression of colon cancer from hyperplasia to dysplasia and ultimately adenocarcinoma and cancer. In addition, it decreased circulating tumor-related leukocytes, main regulators of cancer inflammation. Dietary consumption of ZJ fruit attenuated the formation of ACF and delayed the progression of colon cancer.

Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell.

PubMed

Ding, Jing; Lu, Yong-Ze; Fu, Liang; Ding, Zhao-Wei; Mu, Yang; Cheng, Shuk H; Zeng, Raymond J

2017-03-01

Anaerobic oxidation of methane (AOM) contributes significantly to the global methane sink. Previously, studies of anaerobic methanotrophic (ANME) archaea have been limited as they have not been separable from their bacterial partners during the AOM process because of their dependence on the bacteria. A microbial fuel cell (MFC) is a device capable of directly transforming chemical energy to electrical energy via electrochemical reactions involving biochemical pathways. In this study, decoupling of denitrifying anaerobic methane oxidation (DAMO) archaea and DAMO bacteria was investigated in an microbial fuel cell (MFC) using methane as the fuel. The DAMO fuel cell worked successfully but demonstrated weak electrogenic capability with around 25 mV production. After 45 days' enrichment, the sequencing and fluorescence in situ hybridization results showed the DAMO archaea percentage had increased from 26.96% (inoculum) to 65.77% (electrode biofilm), while the DAMO bacteria percentage decreased from 24.39% to 2.07%. Moreover, the amount of ANME-2d had doubled in the electrode biofilm compared with the inoculum. The sequencing results also showed substantial enrichment of the Ignavibacterium and Geobacter genera. The roles of Ignavibacterium and Geobacter in the MFC system need to be further investigated. Nevertheless, these results illustrate that an MFC device may provide a possible approach to separate DAMO archaea from DAMO bacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enhanced transformation of tetrabromobisphenol a by nitrifiers in nitrifying activated sludge.

PubMed

Li, Fangjie; Jiang, Bingqi; Nastold, Peter; Kolvenbach, Boris Alexander; Chen, Jianqiu; Wang, Lianhong; Guo, Hongyan; Corvini, Philippe François-Xavier; Ji, Rong

2015-04-07

The fate of the most commonly used brominated flame retardant, tetrabromobisphenol A (TBBPA), in wastewater treatment plants is obscure. Using a (14)C-tracer, we studied TBBPA transformation in nitrifying activated sludge (NAS). During the 31-day incubation, TBBPA transformation (half-life 10.3 days) was accompanied by mineralization (17% of initial TBBPA). Twelve metabolites, including those with single benzene ring, O-methyl TBBPA ether, and nitro compounds, were identified. When allylthiourea was added to the sludge to completely inhibit nitrification, TBBPA transformation was significantly reduced (half-life 28.9 days), formation of the polar and single-ring metabolites stopped, but O-methylation was not significantly affected. Abiotic experiments confirmed the generation of mono- and dinitro-brominated forms of bisphenol A in NAS by the abiotic nitration of TBBPA by nitrite, a product of ammonia-oxidizing microorganisms (AOMs). Three biotic (type II ipso-substitution, oxidative skeletal cleavage, and O-methylation) and one abiotic (nitro-debromination) pathways were proposed for TBBPA transformation in NAS. Apart from O-methylation, AOMs were involved in three other pathways. Our results are the first to provide information about the complex metabolism of TBBPA in NAS, and they are consistent with a determining role for nitrifiers in TBBPA degradation by initiating its cleavage into single-ring metabolites that are substrates for the growth of heterotrophic bacteria.

Pocket-Size Interferometric Systems

NASA Astrophysics Data System (ADS)

Waters, James P.; Fernald, Mark R.

1990-04-01

Optical sensors have the intrinsic advantages over electronic sensors of complete safety in hazardous areas and absolute immunity from both transmitting or picking up electromagnetic radiation. However, adoption of optical sensors in real-world applications requires a sensor design which has a sensitivity, resolution, and dynamic range comparable to an equivalent electronic sensor and at the same time must fulfill the practical considerations of small size and low cost. While sensitivity, resolution and dynamic range can be easily achieved with optical heterodyne sensors, the practical considerations make their near-term adoption unlikely. Significant improvements to optical heterodyne vibration and velocity sensors (flexibility, reliability and environmental immunity) have been realized with the use of semiconductor lasers, optical fibers and fiber-optic components. In fact, all of the discrete optical components in a heterodyne interferometer have been replaced with much smaller and more rugged devices except for the optical frequency shifter, acousto-optic modulator (AOM). The AOM and associated power supply, however, account for a substantial portion of both the size and cost. Previous work has shown that an integrated-optic, serrodyne phase modulator with an inexpensive drive circuit can be used for single sideband heterodyne detection. This paper describes the next step, design and implementation of a heterodyne interferometer using integrated-Optic technology to provide the polarization maintaining couplers and phase modulator. The couplers were made using a proton exchange process which produced devices with an extinction ratio of better than 40 dB. The serrodyne phase modulator had the advantage over an AOM of being considerably smaller and having a drive power of less than a milliwatt. The results of this work show that this technology is an effective way of reducing the size of the system and the cost of multiple units without sacarifying performance.

Enhanced susceptibility to acute pneumococcal otitis media in mice deficient in complement C1qa, factor B, and factor B/C2.

PubMed

Tong, Hua Hua; Li, Yong Xing; Stahl, Gregory L; Thurman, Joshua M

2010-03-01

To define the roles of specific complement activation pathways in host defense against Streptococcus pneumoniae in acute otitis media (AOM), we investigated the susceptibility to AOM in mice deficient in complement factor B and C2 (Bf/C2(-/)(-)), C1qa (C1qa(-/)(-)), and factor B (Bf(-)(/)(-)). Bacterial titers of both S. pneumoniae serotype 6A and 14 in the middle ear lavage fluid samples from Bf/C2(-/)(-), Bf(-)(/)(-), and C1qa(-/)(-) mice were significantly higher than in samples from wild-type mice 24 h after transtympanical infection (P < 0.05) and remained persistently higher in samples from Bf/C2(-/)(-) mice than in samples from wild-type mice. Bacteremia occurred in Bf/C2(-/)(-), Bf(-)(/)(-), and C1qa(-/)(-) mice infected with both strains, but not in wild-type mice. Recruitment of inflammatory cells was paralleled by enhanced production of inflammatory mediators in the middle ear lavage samples from Bf/C2(-/)(-) mice. C3b deposition on both strains was greatest for sera obtained from wild-type mice, followed by C1qa(-)(/)(-) and Bf(-)(/)(-) mice, and least for Bf/C2(-)(/)(-) mice. Opsonophagocytosis and whole-blood killing capacity of both strains were significantly decreased in the presence of sera or whole blood from complement-deficient mice compared to wild-type mice. These findings indicate that both the classical and alternative complement pathways are critical for middle ear immune defense against S. pneumoniae. The reduced capacity of complement-mediated opsonization and phagocytosis in the complement-deficient mice appears to be responsible for the impaired clearance of S. pneumoniae from the middle ear and dissemination to the bloodstream during AOM.

Microbial communities in methane seep sediments along US Atlantic Margin are structured by organic matter and seepage dynamics

NASA Astrophysics Data System (ADS)

Graw, M. F.; Pohlman, J.; Treude, T.; Ruppel, C. D.; Colwell, F. S.

2016-12-01

Methane seeps are dynamic environments on continental margins where subsurface methane reaches the ocean. Microbial communities play a critical role in carbon cycling within seep sediments via organic carbon degradation, methane production, and anaerobic oxidation of methane (AOM), which consumes 20-80% of methane in seep sediments. However, biogeochemical controls on microbial community structure at seeps on a margin-wide scale remain unclear. The passive US Atlantic Margin (USAM) has been identified as a region of active methane seepage. Passive margin seeps have traditionally been understudied relative to seeps on active margins. Passive margins exhibit large cross-margin variability in organic carbon deposition and are anticipated to have divergent seep dynamics from active margins. Thus, the USAM offers a unique opportunity to investigate controls on microbial communities in seep sediments. We undertook analysis of microbial communities inhabiting seep sediments at 6 biogeochemically distinct sites along the USAM. Microbiological samples were co-located with measurements of sediment geochemistry and AOM and sulfate reduction rates. Illumina sequencing of the 16S rRNA gene, using both universal (83 samples) and archaeal-specific (64 samples) primers, and the mcrA gene (18 samples) identified 44 bacterial phyla and 7 archaeal phyla. Seeps in canyons and on open slope, likely representing high and low organic content sediments, hosted distinct communities; the former was dominated by ammonia-oxidizing Marine Group I Thaumarchaeota and the latter by mixotrophic Hadesarchaeota. Seep stability also impacted microbial community structure, and in particular the establishment of an AOM community rather than a Bathyarchaeota-dominated community. These findings contribute to understanding how microbial communities are structured within methane seep sediments and pave the way for investigating broad differences in carbon cycling between seeps on passive and active margins.

Optical-fiber-coupled inferometric measurement of tympanic membrane temperature: a new diagnostic tool for acute otitis media

NASA Astrophysics Data System (ADS)

DeRowe, Ari; Ophir, Eyal; Sade, Sharon; Fishman, Gadi; Ophir, Dov; Grankin, Mila; Katzir, Abraham

1998-07-01

A novel infrared (IR) transparent optical fiber coupled to a hand held otoscope and a radiometer was constructed and used to measure the temperatures of the tympanic membrane (TM) and to distinguish between diseased and healthy middle ears. A greater temperature difference between TM readings was found when Acute Otitis Media (AOM) existed in one of the ears examined. This supports the hypothesis that acute inflammation of the middle ear will result in elevated local temperature when measured in such a way that the reading is taken only from the TM without interference of the external canal. The use of an optical fiber enabled temperature measurements of the TM with high spatial resolution eliminating the external ear canal interference. A small patient population was examined and the initial results were statistically significant. In the hands of the primary care physician, this tool would prevent misdiagnosis of AOM preventing indiscriminate use of antibiotics and avoiding complications by early diagnosis.

Absorption spectra analysis of hydrated uranium(III) complex chlorides

NASA Astrophysics Data System (ADS)

Karbowiak, M.; Gajek, Z.; Drożdżyński, J.

2000-11-01

Absorption spectra of powdered samples of hydrated uranium(III) complex chlorides of the formulas NH 4UCl 4 · 4H 2O and CsUCl 4 · 3H 2O have been recorded at 4.2 K in the 4000-26 000 cm -1 range. The analysis of the spectra enabled the determination of crystal-field parameters and assignment of 83 and 77 crystal-field levels for the tetrahydrate and trihydrate, respectively. The energies of the levels were computed by applying a simplified angular overlap model as well as a semiempirical Hamiltonian representing the combined atomic and crystal-field interactions. Ab initio calculations have enabled the application of a simplified parameterization and the determination of the starting values of the AOM parameters. The received results have proved that the AOM approach can quite well predict both the structure of the ground multiplet and the positions of the crystal-field levels in the 17 000-25 000 cm -1 range, usually obscured by strong f-d bands.

Release of Methane from Bering Sea Sediments During the Last Glacial Period

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mea Cook; Lloyd Keigwin

2007-11-30

Several lines of evidence suggest that during times of elevated methane flux the sulfate-methane transition zone (SMTZ) was positioned near the sediment-water interface. We studied two cores (from 700 m and 1457 m water depth) from the Umnak Plateau region. Anomalously low d13C and high d18O in benthic and planktonic foraminifera in these cores are the consequence of diagenetic overgrowths of authigenic carbonates. There are multiple layers of authigenic-carbonate-rich sediment in these cores, and the stable isotope compositions of the carbonates are consistent with those formed during anaerobic oxidation of methane (AOM). The carbonate-rich layers are associated with biomarkers producedmore » by methane-oxidizing archaea, archaeol and glyceryl dibiphytanyl glyceryl tetraether (GDGT). The d13C of the archaeol and certain GDGTs are isotopically depleted. These carbonate- and AOM-biomarker-rich layers were emplaced in the SMTZ during episodes when there was a high flux of methane or methane-rich fluids upward in the sediment column. The sediment methane in the Umnak Plateau region appears to have been very dynamic during the glacial period, and interacted with the ocean-atmosphere system at millennial time scales. The upper-most carbonate-rich layers are in radiocarbon-dated sediment deposited during interstitials 2 and 3, 28-20 ka, and may be associated with the climate warming during this time.« less

Preventive inositol hexaphosphate extracted from rice bran inhibits colorectal cancer through involvement of Wnt/β-catenin and COX-2 pathways.

PubMed

Shafie, Nurul Husna; Mohd Esa, Norhaizan; Ithnin, Hairuszah; Md Akim, Abdah; Saad, Norazalina; Pandurangan, Ashok Kumar

2013-01-01

Nutritional or dietary factors have drawn attention due to their potential as an effective chemopreventive agent, which is considered a more rational strategy in cancer treatment. This study was designed to evaluate the effect of IP₆ extracted from rice bran on azoxymethane- (AOM-) induced colorectal cancer (CRC) in rats. Initially, male Sprague Dawley rats were divided into 5 groups, with 6 rats in each group. The rats received two intraperitoneal (i.p.) injections of AOM in saline (15 mg/kg body weight) over a 2-week period to induce CRC. IP₆ was given in three concentrations, 0.2% (w/v), 0.5% (w/v), and 1.0% (w/v), via drinking water for 16 weeks. The deregulation of the Wnt/β-catenin signaling pathway and the expression of cyclooxygenase (COX)-2 have been implicated in colorectal tumorigenesis. β-Catenin and COX-2 expressions were analysed using the quantitative RT-PCR and Western blotting. Herein, we reported that the administration of IP₆ markedly suppressed the incidence of tumors when compared to the control. Interestingly, the administration of IP₆ had also markedly decreased β-catenin and COX-2 in colon tumors. Thus, the downregulation of β-catenin and COX-2 could play a role in inhibiting the CRC development induced by IP₆ and thereby act as a potent anticancer agent.

In vivo molecular imaging of colorectal cancer using quantum dots targeted to vascular endothelial growth factor receptor 2 and optical coherence tomography/laser-induced fluorescence dual-modality imaging

NASA Astrophysics Data System (ADS)

Carbary-Ganz, Jordan L.; Welge, Weston A.; Barton, Jennifer K.; Utzinger, Urs

2015-09-01

Optical coherence tomography/laser induced fluorescence (OCT/LIF) dual-modality imaging allows for minimally invasive, nondestructive endoscopic visualization of colorectal cancer in mice. This technology enables simultaneous longitudinal tracking of morphological (OCT) and biochemical (fluorescence) changes as colorectal cancer develops, compared to current methods of colorectal cancer screening in humans that rely on morphological changes alone. We have shown that QDot655 targeted to vascular endothelial growth factor receptor 2 (QD655-VEGFR2) can be applied to the colon of carcinogen-treated mice and provides significantly increased contrast between the diseased and undiseased tissue with high sensitivity and specificity ex vivo. QD655-VEGFR2 was used in a longitudinal in vivo study to investigate the ability to correlate fluorescence signal to tumor development. QD655-VEGFR2 was applied to the colon of azoxymethane (AOM-) or saline-treated control mice in vivo via lavage. OCT/LIF images of the distal colon were taken at five consecutive time points every three weeks after the final AOM injection. Difficulties in fully flushing unbound contrast agent from the colon led to variable background signal; however, a spatial correlation was found between tumors identified in OCT images, and high fluorescence intensity of the QD655 signal, demonstrating the ability to detect VEGFR2 expressing tumors in vivo.

Why I Believe I Achieve Determines Whether I Achieve

ERIC Educational Resources Information Center

Siegle, Del; McCoach, D. Betsy; Roberts, Anne

2017-01-01

The beliefs and values students hold toward themselves, given tasks, and achievement itself can influence what tasks students seek, and whether they are able to obtain them. On the basis of previous research on underachievement and motivation, we developed the Achievement Orientation Model (AOM) to explore the issue of student achievement. The…

Quantum dots targeted to vascular endothelial growth factor receptor 2 as a contrast agent for the detection of colorectal cancer

NASA Astrophysics Data System (ADS)

Carbary-Ganz, Jordan L.; Barton, Jennifer K.; Utzinger, Urs

2014-08-01

We successfully labeled colorectal cancer in vivo using quantum dots targeted to vascular endothelial growth factor receptor 2 (VEGFR2). Quantum dots with emission centered at 655 nm were bioconjugated to anti-VEGFR2 antibodies through streptavidin/biotin linking. The resulting QD655-VEGFR2 contrast agent was applied in vivo to the colon of azoxymethane (AOM) treated mice via lavage and allowed to incubate. The colons were then excised, cut longitudinally, opened to expose the lumen, and imaged en face using a fluorescence stereoscope. The QD655-VEGFR2 contrast agent produced a significant increase in contrast between diseased and undiseased tissues, allowing for fluorescence-based visualization of the diseased areas of the colon. Specificity was assessed by observing insignificant contrast increase when labeling colons of AOM-treated mice with quantum dots bioconjugated to isotype control antibodies, and by labeling the colons of saline-treated control mice. This contrast agent has a great potential for in vivo imaging of the colon through endoscopy.

Archaeal populations in hypersaline sediments underlying orange microbial mats in the Napoli mud volcano.

PubMed

Lazar, Cassandre Sara; L'haridon, Stéphane; Pignet, Patricia; Toffin, Laurent

2011-05-01

Microbial mats in marine cold seeps are known to be associated with ascending sulfide- and methane-rich fluids. Hence, they could be visible indicators of anaerobic oxidation of methane (AOM) and methane cycling processes in underlying sediments. The Napoli mud volcano is situated in the Olimpi Area that lies on saline deposits; from there, brine fluids migrate upward to the seafloor. Sediments associated with a brine pool and microbial orange mats of the Napoli mud volcano were recovered during the Medeco cruise. Based on analysis of RNA-derived sequences, the "active" archaeal community was composed of many uncultured lineages, such as rice cluster V or marine benthic group D. Function methyl coenzyme M reductase (mcrA) genes were affiliated with the anaerobic methanotrophic Archaea (ANME) of the ANME-1, ANME-2a, and ANME-2c groups, suggesting that AOM occurred in these sediment layers. Enrichment cultures showed the presence of viable marine methylotrophic Methanococcoides in shallow sediment layers. Thus, the archaeal community diversity seems to show that active methane cycling took place in the hypersaline microbial mat-associated sediments of the Napoli mud volcano.

Prevalence and risk factors of Otitis Media with effusion in school children in Qassim Region of Saudi Arabia

PubMed Central

Humaid, Al-Humaid I.; Ashraf, Abou-halawa S.; Masood, Khan A.; Nuha, Al-Hamamah Salem; Saleh, Al Duways Ali; Awadh, Alanazi Mohammed

2014-01-01

Objective To determine the prevalence of otitis media with effusion (OME) among school children in Qassim region of Kingdom of Saudi Arabia and to determine relevant risk factors in affected children. Methods Through a cross-sectional study, 1488 children in the age range 6–12 years were randomly selected from 25 primary schools in Qassim region. A questionnaire was used to determine risk factors for OME. Otoscopy and tympanometry were used to diagnose and confirm OME. Pure tone average for children with confirmed OME was measured. Teachers of children were asked to complete a questionnaire evaluating child’s level of school performance. Results Prevalence of OME in the study population was 7.5% (112/1488). In univariate analysis, it was strongly associated with age less than 8 years (p< 0.0001; OR= 4.23, 95% CI: 2.85–6.29 ), family size more than 4 members in the household((p<0.0001; OR= 4.45, 95% CI: 2.23–8.88), mother education less than secondary school education (p<0.0001; OR=2.2, 95% CI: 1.47–3.29), recurrent acute otitis media (AOM) (p<0.0001; OR=5.73, 95% CI: 3.47–9.45), and hearing loss symptom (p< 0.0001; OR= 3.39, 95% CI: 1.92–5.99). It is less strongly associated with history of preschool AOM (p= 0.002; OR= 3.15, 95% CI: 1.67–5.97), nasal discharge (p= 0.003; OR= 1.91, 95% CI: 1.24–2.93) and snoring (p=0.03; OR= 1.76, 95% CI: 1.06–2.94). OME was significantly higher in schools located in rural districts (p<0.001, OR= 2.82, 95% CI: 1.86–4.28). In multivariate regression model, five of these factors were found to be predictors of OME: age less than 8 years (OR= 5.052, 95% CI:3.289–7.762), family size more than4 members in the household) (OR= 4.192, 95% CI: 2.033–8.643), rural school district (OR=3.037, 95% CI: 1.933–4.772), mother education lower than secondary school education) (OR=2.041, 95% CI:1.602–3.877) and recurrent AOM (OR=4.914, 95% CI: 2.677–9.02). Children with OME tend to have poorer school performance compared to normal children (p=0.067). No significant correlation was found between OME and type of feeding during the first two years of life (p=0.62; OR= 0.87, 95% CI: 0.51–1.49), preschool daycare attendance (p=0.17; OR= 0.71, 95% CI: 0.44–1.16), home exposure to cigarette smoke (p=0.4; OR= 1.34, 95% CI:0.68–2.65), visits to ENT clinic (p=0.13; OR= 0.58, 95% CI:0.29–1.18), and ENT operations (p=0.12; OR= 0.46, 95% CI: 0.17–1.27). Conclusion Prevalence of OME in Qassim region reaches 7.5% in school children. Age less than 8 years, family size more than 4 members in the household, mother education less than secondary school education, living in rural area and recurrent AOM are found to be predictors of OME in Qassim region. In this population of children, otoscopy and tympanometry should be used as screening tools for OME. PMID:25780352

Carbonate mounds from the Gulf of Cadiz in relation to methane seepage: unrelated phenomena or coupling?

NASA Astrophysics Data System (ADS)

Stadnitskaia, Alina; Baas, Marianne; de Haas, Henk; van Weering, Tjeerd C. E.; Kreulen, Rob R.; Sinninghe Damsté, Jaap S.

2010-05-01

For more than decade, the formation of carbonate mounds, related ecosystem development and organization/functioning of the entire mound habitats are subjects for a growing amount of studies and discussions. Carbonate mounds from the Gulf of Cadiz are of special interest due to their association with active mud volcanoes within the El Arraiche mud volcano field. Such co-occurrence of ecologically contrasting phenomena anticipates complex biogeochemical interactions between a carbonate mound interior and seeping through hydrocarbon-rich fluids. To get closer in understanding of how methane affects a carbonate mound development in the gulf, a combination of inorganic and organic geochemical techniques was applied to two sedimentary cores collected from summits of Alfa and Beta mounds. These mounds were found at the NW slope of the Gimini MV at the Pen Duick Mound Province. We analyzed vertical distribution profiles of sulfate, sulfide, chlorinity, DIC in combination with hydrocarbon gas measurements and lipid biomarker study. To have estimates of Sea Surface Temperature (SST) during the carbonate mound formation, we applied the TEX86 (TetraEther indeX of tetraethers with 86 carbon atoms; Schouten et al., 2002) and the alkenone-based UK37 index (Müller et al., 1998). The pore-water data revealed the presence of brine inflow, which is consistent with the data of Hensen et al., (2007). The behavior of sulfide distribution profiles and δ13C values from dissolved inorganic carbon (DIC) indicated that most of the sulfide and DIC are resulted from the microbial anaerobic oxidation of methane (AOM) processes. In contrast, the analysis of archaeal membrane lipids from distinct clades of AOM-mediating anaerobic methanotrophs showed exceedingly low concentrations of specific biomarkers, which is in contradiction with pore-water and gas chemistry data. Besides, AOM is the main cause for the increase of sedimentary alkalinity that leads to carbonate precipitation. Instead, some sedimentary intervals associated with pore-water-detected AOM zone showed the presence of semi-dissolved coral branches, indicating thus rather acidic intra-environments. In this paper we discuss a potential "consecutive order" of biogeochemical processes in the close subsurface of Alfa and Beta carbonate mounds and outline the importance of careful interpretation of biogeochemical signatures related to past, modern and post seepage episodes. References: Hensen, C, Nuzzo, M, Hornibrook, E, Pinheiro, L M, Bock, B, Magalhães, V, W Bruckmann (2007). Sources of mud volcano fluids in the Gulf of Cadiz: indications for hydrothermal imprint. Geochim. Cosmochimica Acta, 71, 1232-1248. Schouten, S., Hopmans, E.C., Schefub, E., and Sinninghe Damsté, J.S., 2002, Distributional variations in marine crenarchaeotal membrane lipids: a new tool for reconstructing ancient sea water temperatures?: Earth and Planetary Science Letters, v. 204, p. 265-274. Somoza, L., Gardner, J.M., Diaz-del-Rio, V., Vazquez, J.T., Pinheiro, L.M.,Herna‘ndez-Molina, F.J.the TASYO/Anastasya shipboard parties, 2002. Numerous methane gas-related sea floor structures identified in the Gulf of Cadis. EOS, p. 541. Müller, P.J., Kirst, G., Ruhland, G., von Storch I. and A. Rosell-Melé (1998). Calibration of the alkenone paleotemperature index UK'37 based on core-tops from the eastern South Atlantic and the global ocean (60°N-60°S). Geochimica et Cosmochimica Acta 62, pp. 1757-1772. Van Rensbergen, P., Depreiter, D., Pannemans, B. and Henriet, J.-P. (2005) Seafloor expression of sediment extrusion and intrusion at the El Arraiche mud volcano field,Gulf of Cadiz. J. Geophys. Res.110, No. F2, F02010.

Glutathione peroxidase-2 and selenium decreased inflammation and tumors in a mouse model of inflammation-associated carcinogenesis whereas sulforaphane effects differed with selenium supply

PubMed Central

Krehl, Susanne; Loewinger, Maria; Florian, Simone; Kipp, Anna P.; Banning, Antje; Wessjohann, Ludger A.; Brauer, Martin N.; Iori, Renato; Esworthy, Robert S.; Chu, Fong-Fong; Brigelius-Flohé, Regina

2012-01-01

Chronic inflammation and selenium deficiency are considered as risk factors for colon cancer. The protective effect of selenium might be mediated by specific selenoproteins, such as glutathione peroxidases (GPx). GPx-1 and -2 double knockout, but not single knockout mice, spontaneously develop ileocolitis and intestinal cancer. Since GPx2 is induced by the chemopreventive sulforaphane (SFN) via the nuclear factor E2-related factor 2 (Nrf2)/Keap1 system, the susceptibility of GPx2-KO and wild-type (WT) mice to azoxymethane and dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis was tested under different selenium states and SFN applications. WT and GPx2-KO mice were grown on a selenium-poor, -adequate or -supranutritional diet. SFN application started either 1 week before (SFN4) or along with (SFN3) a single AOM application followed by DSS treatment for 1 week. Mice were assessed 3 weeks after AOM for colitis and Nrf2 target gene expression and after 12 weeks for tumorigenesis. NAD(P)H:quinone oxidoreductases, thioredoxin reductases and glutathione-S-transferases were upregulated in the ileum and/or colon by SFN, as was GPx2 in WT mice. Inflammation scores were more severe in GPx2-KO mice and highest in selenium-poor groups. Inflammation was enhanced by SFN4 in both genotypes under selenium restriction but decreased in selenium adequacy. Total tumor numbers were higher in GPx2-KO mice but diminished by increasing selenium in both genotypes. SFN3 reduced inflammation and tumor multiplicity in both Se-adequate genotypes. Tumor size was smaller in Se-poor GPx2-KO mice. It is concluded that GPx2, although supporting tumor growth, inhibits inflammation-mediated tumorigenesis, but the protective effect of selenium does not strictly depend on GPx2 expression. Similarly, SFN requires selenium but not GPx2 for being protective. PMID:22180572

Glutathione peroxidase-2 and selenium decreased inflammation and tumors in a mouse model of inflammation-associated carcinogenesis whereas sulforaphane effects differed with selenium supply.

PubMed

Krehl, Susanne; Loewinger, Maria; Florian, Simone; Kipp, Anna P; Banning, Antje; Wessjohann, Ludger A; Brauer, Martin N; Iori, Renato; Esworthy, Robert S; Chu, Fong-Fong; Brigelius-Flohé, Regina

2012-03-01

Chronic inflammation and selenium deficiency are considered as risk factors for colon cancer. The protective effect of selenium might be mediated by specific selenoproteins, such as glutathione peroxidases (GPx). GPx-1 and -2 double knockout, but not single knockout mice, spontaneously develop ileocolitis and intestinal cancer. Since GPx2 is induced by the chemopreventive sulforaphane (SFN) via the nuclear factor E2-related factor 2 (Nrf2)/Keap1 system, the susceptibility of GPx2-KO and wild-type (WT) mice to azoxymethane and dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis was tested under different selenium states and SFN applications. WT and GPx2-KO mice were grown on a selenium-poor, -adequate or -supranutritional diet. SFN application started either 1 week before (SFN4) or along with (SFN3) a single AOM application followed by DSS treatment for 1 week. Mice were assessed 3 weeks after AOM for colitis and Nrf2 target gene expression and after 12 weeks for tumorigenesis. NAD(P)H:quinone oxidoreductases, thioredoxin reductases and glutathione-S-transferases were upregulated in the ileum and/or colon by SFN, as was GPx2 in WT mice. Inflammation scores were more severe in GPx2-KO mice and highest in selenium-poor groups. Inflammation was enhanced by SFN4 in both genotypes under selenium restriction but decreased in selenium adequacy. Total tumor numbers were higher in GPx2-KO mice but diminished by increasing selenium in both genotypes. SFN3 reduced inflammation and tumor multiplicity in both Se-adequate genotypes. Tumor size was smaller in Se-poor GPx2-KO mice. It is concluded that GPx2, although supporting tumor growth, inhibits inflammation-mediated tumorigenesis, but the protective effect of selenium does not strictly depend on GPx2 expression. Similarly, SFN requires selenium but not GPx2 for being protective.

Suppressive Effect of Zinc on the Formation of Colonic Preneoplastic Lesions in the Mouse Fed High Levels of Dietary Iron

PubMed Central

Park, Hyunji; Kang, Bong Su; Kim, Dang Young; Yoon, Ja Seon; Jeong, Jae-Hwang; Nam, Sang Yoon; Yun, Young Won

2012-01-01

We investigated the effect of zinc on the formation of colonic aberrant crypt foci induced by azoxymethane (AOM) followed by dextran sodium sulfate (DSS) in mice with high iron diet (HFe; 450 ppm iron). Sixweek old ICR mice were fed on high iron diets with combination of three different levels of zinc in diets, low-zinc (LZn; 0.01 ppm), medium-zinc (MZn; 0.1 ppm), and high-zinc (HZn; 1 ppm) for 12 weeks. Animals were received weekly intraperitoneal injections of AOM (10 mg/kg B.W. in saline) for 3 weeks followed by 2% DSS (molecular weight 36,000~50,000) in the drinking water for a week. To confirm the iron storage in the body, the hepatic iron concentration has been determine chemically and compared with histological assessment visualized by Prussian blue reaction. Aberrant crypt (AC) and aberrant crypt foci (ACF) were analyzed in the colonic mucosa of mouse fed high dietary iron. Superoxide dismutase (SOD) activity and thiobarbituric acid-reactive substances (TBARS) level were also investigated. Apoptosis in the preneoplastic lesion was determined by terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling (TUNEL). In addition, immunohistochemistry of β-catenin was also performed on the mucous membrane of colon. The number of large ACF (≥ 4 AC/ACF), which possess greater tumorigenic potential, was significantly lower in MZn and HZn groups compared with LZn group. Cytosolic SOD activity in the liver was significantly higher in HZn group compared with LZn group. Hepatic MDA level was decreased significantly in HZn group compared with MZn and LZn groups. Apoptotic index was significantly higher in HZn group. Taken together, these findings indicate that dietary zinc might exert a protective effect against colonic preneoplastic lesion induced by AOM/DSS in ICR mice with high iron status, and suggest that dietary supplement of zinc might play a role in suppressing colon carcinogenesis in mice. PMID:24278588

The Health Economic Impact of Universal Infant Vaccination with the 10-Valent Pneumococcal Nontypeable Haemophilus influenzae Protein D Conjugate Vaccine as Compared with 13-Valent Pneumococcal Conjugate Vaccine in Hong Kong.

PubMed

Lee, Kenneth K C; Chia Wu, David Bin; Topachevskyi, Oleksandr; Delgleize, Emmanuelle; DeAntonio, Rodrigo

2013-05-01

Pneumococcal universal vaccination in Hong Kong was introduced in 2009. We assessed the health and economic impact of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine (PCV-10) compared with the current 13-valent pneumococcal conjugate vaccine (PCV-13) recommended for Hong Kong in 2011, providing new elements to be considered by public health authorities in the future decision-making process for pneumococcal vaccines in this country. An analytical model was used to estimate the annual economic and health outcomes of invasive pneumococcal disease (IPD), community-acquired pneumonia, and acute otitis media (AOM), including nontypeable H. influenzae-related AOM, for a birth cohort in Hong Kong from the payer perspective with a 10-year horizon. Clinical impact including morbidity-mortality, quality-adjusted life-years (QALYs), incremental costs, and cost-effectiveness comparing PCV-10 and PCV-13 were estimated. Probabilistic sensitivity analyses by using alternate scenarios were performed. Model projections indicate that PCV-13 and PCV-10 have approximately equivalent impact on the prevention of deaths caused by IPD and pneumonia. PCV-13 is projected to prevent 6 additional cases of IPD, whereas PCV-10 is projected to prevent 13,229 additional AOM cases and 101 additional QALYs. For the base case, PCV-10 vaccination is estimated to save 44.6 million Hong Kong dollars (34.1 million Hong Kong dollars discounted). Sensitivity analysis indicated that PCV-10 would generate more QALYs and save costs as compared with PCV-13. Universal infant vaccination with new available pneumococcal vaccines is expected to generate a significant additional impact on reducing the burden of pneumococcal diseases in Hong Kong. PCV-10 vaccination would be potentially a cost-saving strategy compared with PCV-13 vaccination, generating better cost offsets and higher QALY gains. Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Distribution of microbial methanogenesis, methane oxidation, and sulfate reduction in a high-temperature subduction system of the Nankai Trough off Cape Muroto (IODP Expedition 370 T-Limit, Site C0023)

NASA Astrophysics Data System (ADS)

Treude, T.; Kallmeyer, J.; Beulig, F.; Glombitza, C.; Schubert, F.; Krause, S.; Heuer, V.; Inagaki, F.; Morono, Y.

2017-12-01

The aim of the IODP Expedition 370 is to explore the temperature limit of the deep biosphere in a sub-seafloor environment located in the Nankai Trough, where in-situ sediment temperature increases from 2°C at the seafloor to about 120°C at the 1.2 km deep sediment/basement interface. Our study focuses on the exploration of potential microbial methanogenesis, anaerobic oxidation of methane (AOM), and sulfate reduction in sediments from different depths (from ca. 200 to 1170 mbsf) exposed to several temperature settings in the laboratory (40, 60, 75/80 and 95°C). The drill site, which features a décollement between ca. 758-796 mbsf, includes a sulfate-poor methanogenic zone from approx. 400 to 600 mbsf, followed by a deep methane-sulfate transition zone between approx. 600 to 800 m, which transitions into a deep sulfate-rich zone. Potential microbial activity of hydrogenotrophic methanogenesis, AOM, and sulfate reduction was determined in incubations of sediment slurries produced from whole-round cores with H2-added artificial seawater medium using radioisotope techniques (14C-bicarbonate, 14C-methane, and 35S-sulfate, respectively). Preliminary results revealed two peaks of methanogenesis activity with rates in the order of 0.2 to 0.5 pmol g-1dw d-1. One peak was located within the methane-rich zone passing into the methane-sulfate transition zone (60 to 80°C incubations), while the second peak occurred close to the basement (below 1000 mbsf, 95°C incubation). Sulfate reduction activity was generally highest above 400 mbsf ( 1000 pmol cm-3 d-1, 40°C incubation). Below 400 mbsf, rates declined to levels between 0.1 and 10 pmol cm-3 d-1 (60-95 °C incubations) without a clear trend and continued until close to the bottom of the core. The results point to potentially thermophilic and hypothermophilic microorganisms that exist under very low energy conditions. Samples from AOM incubations are currently being processed and preliminary results will be presented at the meeting as well as the results for sulfate reduction incubations with methane and acetate amendments.

Short-course antibiotics for acute otitis media.

PubMed

Kozyrskyj, Anita; Klassen, Terry P; Moffatt, Michael; Harvey, Krystal

2010-09-08

Acute otitis media (AOM) is a common illness during childhood, for which antibiotics are frequently prescribed. To determine the effectiveness of a short course of antibiotics (less than seven days) in comparison to a long course of antibiotics (seven days or greater) for the treatment of AOM in children. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 4) which contains the Acute Respiratory Infections Group's Specialised Register, MEDLINE, EMBASE, MEDLINE In-Process & Other Non-Indexed Citations, CINAHL, BIOSIS Previews, OCLC Papers First and Proceedings First, Proquest Dissertations and Theses (inception to November 2009); International Pharmaceutical Abstracts, the NLM Gateway, ClinicalTrials.gov and Current Controlled Trials (inception to August 2008). Trials were included if they met the following criteria: participants aged one month to 18 years; clinical diagnosis of ear infection; no previous antimicrobial therapy; and randomisation to treatment with less than seven days versus seven days or more of antibiotics. The primary outcome of treatment failure was defined as the absence of clinical resolution, relapse or recurrence of AOM during one month following initiation of therapy. Treatment outcomes were extracted from individual studies and combined in the form of a summary odds ratio (OR). A summary OR of 1.0 indicates that the treatment failure rate following less than seven days of antibiotic treatment was similar to the failure rate following seven days or more of treatment. This update included 49 trials containing 12,045 participants. Risk of treatment failure was higher with short courses of antibiotics (OR 1.34, 95% CI 1.15 to 1.55) at one month after initiation of therapy (21% failure with short-course treatment and 18% with long-course; absolute difference of 3% between groups). There were no differences found when examining treatment with ceftriaxone for less than seven days (30% failure in those receiving ceftriaxone and 27% in short-acting antibiotics administered for seven days or more) or azithromycin for less than seven days (18% failure in both those receiving azithromycin and short-acting antibiotics administered for seven days or more) with respect to risk of treatment failure at one month or less. Significant reductions in gastrointestinal adverse events were observed for treatment with short-acting antibiotics and azithromycin. Clinicians need to evaluate whether the minimal short-term benefit from longer treatment of antibiotics is worth exposing children to a longer course of antibiotics.

Patterns of methane-related carbonate formation in the black sea

NASA Astrophysics Data System (ADS)

Reitner, J.; Peckmann, J.; Reimer, A.; Thiel, V.

2003-04-01

Methane seeps on the northwestern Black Sea shelf were investigated during the GHOSTDABS expedition in 2001. Seep areas close to the Dniepr Canyon are sites of intense carbonate formation. In anoxic waters, at depths between 200 and 400 m, we found three different modes of seepage-induced carbonate precipitation. The most spectacular type comprises up to 4 m high Ca-carbonate towers flushed by methane gas (type 1). These buildups are constructed of cm to dm-scale calcified hollow spheres which are made and later surrounded by microbial mats. At the base of these microbial mats the spheres are stabilized by a continuous rim of carbonate cement. At a later stage, the fragile spheres are entirely cemented by fibrous aragonite and Mg calcite. The towers harbour a highly diverse microbial community, which are, at least in part, based on the anaerobic oxidation of methane (AOM). A second variety of methane-derived carbonates was observed in the vicinity of the large carbonate towers and consists of lenticular concretions growing within the sediment (type 2). The concretions are up to several decimeters in size and consist of Mg calcite crystal aggregates that progressively fuse together, thereby incorporating ambient sedimentary matter. Associated biofilms surrounding the concretions clearly show AOM related populations but exhibit a different community structure and a smaller microbial diversity than type 1 carbonates. Type 3 encompasses background sediments irregularly cemented with microcrystalline Mg-calcite (automicrite). These precipitates may show very thin internal biofilms, and are further characterized by small, “birds eye”-type cavities. These cavities appear to arise from ascending gas bubbles, and are partly cemented by granular to blocky Mg calcites. The internal surfaces are frequently coated by thin biofilms resembling those found associated with type 2 concretions. All studied Ca-carbonates have low d13C values (-25 to -35 permille vs. PDB) and show a strong autofluorescence due to inclusions of intracrystalline organic matter. We assume that an increase in carbonate alkalinity due to AOM triggers carbonate precipitation on organic matrices provided by extracellular polymeric substances (EPS). Electron microscopic evidence also suggests that the internal alignment of sugar-rich EPS molecules may control the spatial arrangement of the calcification fabrics observed. EPS remains were extracted from the methane carbonates and the function was tested by in vitro calcification/inhibition experiments.

Açaí Berries Inhibit Colon Tumorigenesis in Azoxymethane/Dextran Sulfate Sodium-Treated Mice

PubMed Central

Choi, Yoon Jin; Choi, Yoon Jeong; Kim, Nayoung; Nam, Ryoung Hee; Lee, Seonmin; Lee, Hye Seung; Lee, Ha-Na; Surh, Young-Joon; Lee, Dong Ho

2017-01-01

Background/Aims The aim of this study was to investigate the protective effect of açaí against azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colorectal cancer development. Methods The effect of açaí on tumorigenesis was assessed by evaluating tumor incidence, multiplicity and invasiveness in the mouse colon. The levels of myeloperoxidase (MPO) and proinflammatory cytokines (tumor necrosis factor α [TNF-α], interleukin [IL]-1β, and IL-6) were measured via enzyme-linked immunosorbent assay. Protein levels of cyclooxygenase 2 (COX-2), proliferating cell nuclear antigen (PCNA), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad) and cleaved-caspase-3 were assessed by immunoblotting. Results Administration of pellets containing 5% açaí powder reduced the incidences of both colonic adenoma and cancer (adenoma, 23.1% vs 76.9%, respectively, p=0.006; cancer, 15.4% vs 76.9%, respectively, p=0.002). In the açaí-treated mice, the MPO, TNF-α, IL-1β and IL-6 levels in the colon were significantly down-regulated. Açaí inhibited PCNA and Bcl-2 expression and increased Bad and cleaved-caspase-3 expression. In vitro studies demonstrated that açaí treatment reduced lipopolysaccharide-induced expression of TNF-α, IL-1β, IL-6 and COX-2 in murine macrophage RAW 264.7 cells. Conclusions Açaí demonstrated protective effects against AOM/DSS-induced colon carcinogenesis, which suggests that the intake of açaí may be beneficial for the prevention of human colon cancer. PMID:27965474

"Medical education is the ugly duckling of the medical world" and other challenges to medical educators' identity construction: a qualitative study.

PubMed

Sabel, Esther; Archer, Julian

2014-11-01

The authors first aimed to ascertain how the Academy of Medical Educators (AoME) could develop and support early career medical educators. They expanded their study to explore the challenges to defining medical education as a discipline because of a lack of collective identity among educators. In 2010, the authors and members of the AoME Early Careers Working Group conducted focus groups with early career medical educators (clinicians and scientists) and interviews with senior medical educators in the United Kingdom. All focus groups and interviews were audio recorded and transcribed verbatim. The authors used an interpretative phenomenological analysis to explore how medical educators described events or phenomena in their careers. They inductively identified overarching theoretical perspectives to understand observed phenomena drawing on social identity theories. The authors conducted nine focus groups with 34 participants in total and six interviews. Participants identified fundamental challenges to their identity as a medical educator; they understood their medical education role to be secondary to their primary role as clinician or scientist. Participants noted that they had not developed an emotional attachment to medical education. Their relationship with the field remained at an operational level, revolving around roles and responsibilities. Medical educators' social cohesion is threatened by their sense that educators are poor relations compared with scientists and clinicians. While medical educators' identities may be in crisis, they also are changing, a change needed for medical education, medical education research, the practice of medicine, and ultimately patient care.

Black Raspberries Enhance Natural Killer Cell Infiltration into the Colon and Suppress the Progression of Colorectal Cancer

PubMed Central

Pan, Pan; Kang, Siwen; Wang, Youwei; Liu, Ka; Oshima, Kiyoko; Huang, Yi-Wen; Zhang, Jianying; Yearsley, Martha; Yu, Jianhua; Wang, Li-Shu

2017-01-01

Natural killer (NK) cells are an essential component of innate immunity against cancer development. Many studies have been conducted to evaluate immune-modulating effects using dietary compounds. Our laboratory has been investigating the chemopreventive potential of black raspberries (BRBs) and previously demonstrated their beneficial modulation of genetic and epigenetic biomarkers in patients with colorectal cancer (CRC). The current study investigated their potential on modulating NK cells. To avoid the excessive inflammation caused by the dextran sulfate sodium (DSS) treatment that leads to colitis, we treated the mice with overnight DSS so that it would slightly irritate the colon but still promote colon carcinogenesis with 100% incidence in both the ApcMin/+ mice and azoxymethane (AOM)-treated mice. A significant decrease of tissue-infiltrating NK cells along the progression of microadenoma-to-adenoma and adenoma-to-adenocarcinoma was observed in the ApcMin/+/DSS and AOM/DSS mice, respectively. Depletion of NK cells significantly promoted the development of CRC, suggesting a critical role of NK cells in combating CRC progression. BRBs significantly suppressed the CRC progression and increased the number of tissue-infiltrating NK cells in both mouse models. Moreover, we further determined BRBs’ effects on NK cells in the human biopsy specimens collected from our previously completed clinical trial, in which CRC patients consumed BRBs for an average of 4 weeks during a presurgical window. We observed an increased number and an enhanced cytotoxicity of NK cells by BRB intervention. The current study provides evidence that BRBs have the potential to enhance the tumor immunesurveillance of NK cells that can be beneficial in the setting of CRC prevention and treatment. PMID:28861089

Methane seepage intensities traced by biomarker patterns in authigenic carbonates from the South China Sea

NASA Astrophysics Data System (ADS)

Guan, H.; Feng, D.

2015-12-01

Authigenic carbonate rocks from an active seep (Site F) at 1120 m water depth of the South China Sea (SCS) were studied using mineralogical and lipid biomarker analyses. Carbonate mineral compositions, in specific samples, were predominantly aragonite, high-Mg calcite (HMC), or a mixture of both. Abundant 13C-depleted lipid biomarkers (various isoprenoids) diagnostic for archaea provide evidence that anaerobic oxidation of methane (AOM) mediated by anaerobic methane oxidizing archaea (ANME) and their bacterial partners is the major process leading to formation of the carbonates. Nearly a pure suite of AOM biomarkers was preserved in aragonitic carbonate in which predominant consortia were most likely ANME-2/Desulfosarcina & Desulfococcus (DSS) assemblages and a mixture of ANME-2/DSS and ANME-1/DSS consortia in the mixed mineral sample, the predominant consortia are in good accordance with the point that the relative higher methane seepage intensity favors the precipitation of aragonite over HMC. In contrast, the completely different biomarker patterns in HMC sample were mainly composed terrestrial organic matter and marine Thaumarchaea, which most likely originally within sediments accompanied with high organic matter input and low methane supply. This environment is known to be favored for archaea of ANME-1 and precipitation of HMC. High concentrations of 13C-depleted hopanoids, including diplopterol, hopanoic acids and hopanols were observed in the aragonite sample that may be sourced by the intermittent presence of oxic conditions in an overall anoxic condition, which was possibly induced by changing seepage intensities.

ShaoYao decoction ameliorates colitis-associated colorectal cancer by downregulating proinflammatory cytokines and promoting epithelial-mesenchymal transition

PubMed Central

2014-01-01

Abstracts Background Shaoyao decoction (SYD) is a traditional Chinese medicine prescription formulated by Liu Wan-Su, a master of traditional Chinese medicine in Jin-Yuan Dynasty. SYD is effective in treating ulcerative colitis. Paeonol, a component of SYD, inhibits colorectal cancer (CRC) cell proliferation and induces CRC cell apoptosis. In this study, azoxymethane (AOM)/dextran sodium sulfate (DSS)–induced colitis-associated CRC (caCRC) model and CRC cell lines were used to examine the effects of SYD on CRC in vivo and in vitro. Methods A translational medicine strategy based on phytomics quality control was adopted. Liquid chromatography was employed for the chemical characterization and chemical fingerprinting of SYD. Protein expression and macrophage existence were determined by immunohistochemistry and western blot. Serum cytokines were quantified by Luminex assay. Results AOM/DSS-induced caCRC phenotypically resembled human caCRC. SYD significantly increased the survival rate of the mice, ameliorated the general well-being of the mice, and reduced the incidence and multiplicity of colonic neoplasms. SYD inhibited epithelial–mesenchymal transition (EMT), as indicated by upregulated epithelia cadherin and downregulated neuronal cadherin, fibronectin, vimentin, and transcription factor Snail. SYD reduced the expression levels of serum interleukin 1β, interleukin-6, tumor necrosis factor α, tumor-associated macrophages, and p65. These results showed that SYD can attenuate proinflammatory cytokines and inhibit EMT. Conclusions SYD ameliorates caCRC by suppressing inflammation and inhibiting EMT. SYD might be an alternative therapy for caCRC. PMID:24766737

Interfacial interactions between Skeletonema costatum extracellular organic matter and metal oxides: Implications for ceramic membrane filtration.

PubMed

Zaouri, Noor; Gutierrez, Leonardo; Dramas, Laure; Garces, Daniel; Croue, Jean-Philippe

2017-06-01

In the current study, the interfacial interactions between the high molecular weight (HMW) compounds of Skeletonema costatum (SKC) extracellular organic matter (EOM) and ZrO 2 or Al 2 O 3 , were investigated by atomic force microscopy (AFM). HMW SKC-EOM was rigorously characterized and described as a hydrophilic organic compound mainly comprised of polysaccharide-like structures. Lipids and proteins were also observed, although in lower abundance. HMW SKC-EOM displayed attractive forces during approaching (i.e., leading to jump-to-contact events) and adhesion forces during retracting regime to both metal oxides at all solution conditions tested, where electrostatics and hydrogen bonding were suggested as dominant interacting mechanisms. However, the magnitude of these forces was significantly higher on ZrO 2 surfaces, irrespective of cation type (Na + or Ca 2+ ) or concentration. Interestingly, while HMW SKC-EOM interacting forces to Al 2 O 3 were practically insensitive to solution chemistry, the interactions between ZrO 2 and HMW SKC-EOM increased with increasing cation concentration in solution. The structure, and lower charge, hydrophilicity, and density of hydroxyl groups on ZrO 2 surface would play a key role on favoring zirconia associations with HMW SKC-EOM. The current results contribute to advance our fundamental understanding of Algogenic Organic Matter (AOM) interfacial interactions with metal oxides (i.e., AOM membrane fouling), and would highly assist in the proper selection of membrane material during episodic algal blooms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Use of complementary and alternative medicine in children with recurrent acute otitis media in Italy.

PubMed

Marchisio, P; Bianchini, S; Galeone, C; Baggi, E; Rossi, E; Albertario, G; Torretta, S; Pignataro, L; Esposito, S; Principi, N

2011-01-01

Controlling environmental factors, chemoprophylaxis, immunoprophylaxis and surgery are considered possible means of preventing recurrent acute otitis media (RAOM), but there are no available data concerning the paediatric use of complementary and alternative medicine (CAM). We evaluated the uses of CAM (homeopathy and/or herbal medicine) as means of preventing AOM in children with a history of RAOM. Eight hundred and forty Italian children with RAOM (≥3 episodes in six months) aged 1-7 years were surveyed in 2009 using a face-to-face questionnaire, filled by parents or caregivers, that explored the prevalence, determinants, reasons, cost, and perceived safety and efficacy of CAM. About one-half (46%) of the children used CAM, significantly more than the number who used immunoprophylaxis (influenza vaccine 15%; p<0.05), PCV-7 34%; p<0.05) or chemoprophylaxis (2%; p<0.001). Use of CAM in the family was the only important factor positively associated with the use of CAM in children (adjusted OR 7.94; 95% CI: 5.26-11.99). The main reasons for using CAM were a fear of the adverse effects of conventional medicine (40%) and to increase host defences (20%). CAM was widely seen as safe (95%) and highly effective (68%). CAM prescribers were paediatricians in 50.7% of cases; self-initiation was reported by 23% of respondents. CAM expenditure was between Euro 25 and Euro 50/month in 27.6% of cases and ≥ Euro 50/month in 16%. Children with RAOM should be considered among the categories of subjects likely to be using CAM. Together with the fact that paediatricians are the main prescribers, this is worrying because of the current lack of evidence regarding the efficacy, safety and cost-effectiveness of CAM in the prevention of RAOM.

Comammox in drinking water systems.

PubMed

Wang, Yulin; Ma, Liping; Mao, Yanping; Jiang, Xiaotao; Xia, Yu; Yu, Ke; Li, Bing; Zhang, Tong

2017-06-01

The discovery of complete ammonia oxidizer (comammox) has fundamentally upended our perception of the global nitrogen cycle. Here, we reported four metagenome assembled genomes (MAGs) of comammox Nitrospira that were retrieved from metagenome datasets of tap water in Singapore (SG-bin1 and SG-bin2), Hainan province, China (HN-bin3) and Stanford, CA, USA (ST-bin4). Genes of phylogenetically distinct ammonia monooxygenase subunit A (amoA) and hydroxylamine dehydrogenase (hao) were identified in these four MAGs. Phylogenetic analysis based on ribosomal proteins, AmoA, hao and nitrite oxidoreductase (subunits nxrA and nxrB) sequences indicated their close relationships with published comammox Nitrospira. Canonical ammonia-oxidizing microbes (AOM) were also identified in the three tap water samples, ammonia-oxidizing bacteria (AOB) in Singapore's and Stanford's samples and ammonia-oxidizing archaea (AOA) in Hainan's sample. The comammox amoA-like sequences were also detected from some other drinking water systems, and even outnumbered the AOA and AOB amoA-like sequences. The findings of MAGs and the occurrences of AOM in different drinking water systems provided a significant clue that comammox are widely distributed in drinking water systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Widely tunable laser frequency offset lock with 30 GHz range and 5 THz offset.

PubMed

Biesheuvel, J; Noom, D W E; Salumbides, E J; Sheridan, K T; Ubachs, W; Koelemeij, J C J

2013-06-17

We demonstrate a simple and versatile method to greatly extend the tuning range of optical frequency shifting devices, such as acousto-optic modulators (AOMs). We use this method to stabilize the frequency of a tunable narrow-band continuous-wave (CW) laser to a transmission maximum of an external Fabry-Perot interferometer (FPI) with a tunable frequency offset. This is achieved through a servo loop which contains an in-loop AOM for simple radiofrequency (RF) tuning of the optical frequency over the full 30 GHz mode-hop-free tuning range of the CW laser. By stabilizing the length of the FPI to a stabilized helium-neon (HeNe) laser (at 5 THz offset from the tunable laser) we simultaneously transfer the ~ 1 MHz absolute frequency stability of the HeNe laser to the entire 30 GHz range of the tunable laser. Thus, our method allows simple, wide-range, fast and reproducible optical frequency tuning and absolute optical frequency measurements through RF electronics, which is here demonstrated by repeatedly recording a 27-GHz-wide molecular iodine spectrum at scan rates up to 500 MHz/s. General technical aspects that determine the performance of the method are discussed in detail.

Archaeal Populations in Hypersaline Sediments Underlying Orange Microbial Mats in the Napoli Mud Volcano▿†

PubMed Central

Lazar, Cassandre Sara; L'Haridon, Stéphane; Pignet, Patricia; Toffin, Laurent

2011-01-01

Microbial mats in marine cold seeps are known to be associated with ascending sulfide- and methane-rich fluids. Hence, they could be visible indicators of anaerobic oxidation of methane (AOM) and methane cycling processes in underlying sediments. The Napoli mud volcano is situated in the Olimpi Area that lies on saline deposits; from there, brine fluids migrate upward to the seafloor. Sediments associated with a brine pool and microbial orange mats of the Napoli mud volcano were recovered during the Medeco cruise. Based on analysis of RNA-derived sequences, the “active” archaeal community was composed of many uncultured lineages, such as rice cluster V or marine benthic group D. Function methyl coenzyme M reductase (mcrA) genes were affiliated with the anaerobic methanotrophic Archaea (ANME) of the ANME-1, ANME-2a, and ANME-2c groups, suggesting that AOM occurred in these sediment layers. Enrichment cultures showed the presence of viable marine methylotrophic Methanococcoides in shallow sediment layers. Thus, the archaeal community diversity seems to show that active methane cycling took place in the hypersaline microbial mat-associated sediments of the Napoli mud volcano. PMID:21335391

Enhanced angular overlap model for nonmetallic f -electron systems

NASA Astrophysics Data System (ADS)

Gajek, Z.

2005-07-01

An efficient method of interpretation of the crystal field effect in nonmetallic f -electron systems, the enhanced angular overlap model (EAOM), is presented. The method is established on the ground of perturbation expansion of the effective Hamiltonian for localized electrons and first-principles calculations related to available experimental data. The series of actinide compounds AO2 , oxychalcogenides AOX , and dichalcogenides UX2 where X=S ,Se,Te and A=U ,Np serve as probes of the effectiveness of the proposed method. An idea is to enhance the usual angular overlap model with ab initio calculations of those contributions to the crystal field potential, which cannot be represented by the usual angular overlap model (AOM). The enhancement leads to an improved fitting and makes the approach intrinsically coherent. In addition, the ab initio calculations of the main, AOM-consistent part of the crystal field potential allows one to fix the material-specific relations for the EAOM parameters in the effective Hamiltonian. Consequently, the electronic structure interpretation based on EAOM can be extended to systems of the lowest point symmetries or/and deficient experimental data. Several examples illustrating the promising capabilities of EAOM are given.

Korean clinical practice guidelines: otitis media in children.

PubMed

Lee, Hyo-Jeong; Park, Su-Kyoung; Choi, Kyu Young; Park, Su Eun; Chun, Young Myung; Kim, Kyu-Sung; Park, Shi-Nae; Cho, Yang-Sun; Kim, Young-Jae; Kim, Hyung-Jong; Korean Otologic Society

2012-08-01

Acute otitis media (AOM) and otitis media with effusion (OME) are common infections in children, and their diagnosis and treatment have significant impacts on the health of children and the costs of providing national medical care. In 2009, the Korean Otologic Society organized a committee composed of experts in the field of otolaryngology, pediatrics, and family medicine to develop Korean clinical practice guidelines (CPG) for otitis media in children with the goal of meeting regional medical and social needs in Korea. For this purpose, the committee adapted existing guidelines. A comprehensive literature review was carried out primarily from 2004 to 2009 using medical search engines including data from Korea. A draft was written after a national questionnaire survey and several public audits, and it was editorially supervised by senior advisors before publication of the final report. These evidence-based guidelines for the management of otitis media in children provide recommendations to primary practitioners for the diagnosis and treatment of children younger than 15 yr old with uncomplicated AOM and OME. The guidelines include recommendations regarding diagnosis, treatment options, prevention and parent education, medical records, referral, and complementary/alternative medicine for treating pediatric otitis media.

Polydyne displacement interferometer using frequency-modulated light

NASA Astrophysics Data System (ADS)

Arablu, Masoud; Smith, Stuart T.

2018-05-01

A radio-frequency Frequency-Modulated (FM) signal is used to diffract a He-Ne laser beam through an Acousto-Optic Modulator (AOM). Due to the modulation of the FM signal, the measured spectra of the diffracted beams comprise a series of phase-synchronized harmonics that have exact integer frequency separation. The first diffraction side-beam emerging from the AOM is selected by a slit to be used in a polydyne displacement interferometer in a Michelson interferometer topology. The displacement measurement is derived from the phase measurement of selected modulation harmonic pairs. Individual harmonic frequency amplitudes are measured using discrete Fourier transform applied to the signal from a single photodetector. Phase signals are derived from the changes in the amplitudes of different harmonic pairs (typically odd-even pairs) with the phase being extracted using a standard quadrature method. In this study, two different modulation frequencies of 5 and 10 kHz are used at different modulation depths. The measured displacements by different harmonic pairs are compared with a commercial heterodyne interferometer being used as a reference for these studies. Measurements obtained from five different harmonic pairs when the moving mirror of the interferometer is scanned over ranges up to 10 μm all show differences of less than 50 nm from the reference interferometer measurements. A drift test was also used to evaluate the differences between the polydyne interferometer and reference measurements that had different optical path lengths of approximately 25 mm and 50 mm, respectively. The drift test results indicate that about half of the differences can be attributed to temperature, pressure, and humidity variations. Other influences include Abbe and thermal expansion effects. Rough magnitude estimates using simple models for these two effects can account for remaining observed deviations.

Pediatric otitis media in Fiji: Survey findings 2015.

PubMed

Fang, Te-Yung; Rafai, Eric; Wang, Pa-Chun; Bai, Chiy-Huey; Jiang, Peng-Long; Huang, Shu-Nuan; Chen, You-Ju; Chao, Yi-Ting; Wang, Chen-Hsu; Chang, Chia-Hsiu

2016-06-01

Otitis media (OM), as a common infectious disease, is a major cause of hearing impairment among the general population. OM remains a major public health threat in the Pacific islands, but the risks of OM have not been thoroughly explored in this region. The objective of this study is to investigate the prevalence, clinical features, and quality-of-life impacts of OM in Fiji. In the medical service trip entitled "Healing and Hope - Taiwan Cathay Heart and Hearing Medical Mission to Fiji" (TCHHMMF), we conducted a cross-sectional OM survey study in Suva and Sigatoka areas (Korolevu, Cuvu, and Lomawai) in the summer of 2015. The otitis media - 6 (OM-6) was used to survey the OM-related quality of life. In the 467 pediatric patients (aged 0-18 years old) screened, 13 (2.78%) have acute otitis media (AOM), 37 (7.92%) have otitis media with effusion (OME), and 19 (4.1%) have chronic otitis media (COM). Age (OR 0.53, 95% CI: 0.36-0.77) is a significant predictor of AOM, whereas male gender (OR 2.46, 95% CI: 1.13-5.37), smoke exposure (OR 2.81, 95% CI: 1.01-7.82), and concomitant chronic sinusitis (OR 6.05, 95% CI: 2.31-15.88) are significant predictors of OME. The mean OM-6 item scores are highest in caregiver concerns (3.8), physical suffering (3.7), and hearing loss (3.4) domains. OM is an important primary care disease in Fiji that remains under-served. It is critical to educate professionals, parents, and patients to detect and to improve care for OM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Pro-inflammatory interleukins in middle ear effusions from atopic and non-atopic children with chronic otitis media with effusion.

PubMed

Zielnik-Jurkiewicz, Beata; Stankiewicz-Szymczak, Wanda

2016-06-01

Chronic otitis media with effusion (OME) is associated with irreversible changes in the middle ear, sometimes leading to hearing loss and abnormal language development in children. While the pathogenesis of OME is not fully understood, inflammatory and allergic factors are thought to be involved. The study aimed to investigate the role of cytokines in the local development of chronic OME, and assess differences in the cytokine profiles between atopic and non-atopic children. 84 atopic and non-atopic children with chronic OME (mean age of 6 years 7 months) were studied. Age-matched children with hypertrophy of the adenoids and Eustachian tube dysfunction served as the control group. The number of past acute otitis media (AOM) episodes, their age, and the type of effusion were recorded for all children. Pro-inflammatory cytokine concentrations (TNF-α, IL-1β, IL-6 and IL-8) were determined and the presence of pathogenic bacteria in the patients' effusions was examined. High concentrations of TNF-α, IL-1β, IL-6 and IL-8 were found in the effusions in all children with chronic OME, with the highest levels observed in the non-atopic group. The atopic group showed persistently high IL-1β levels, while in the non-atopic children, IL-1β and TNF-α levels positively correlated with the patient's age and the number of past AOM episodes. Pathogenic bacteria were more frequently isolated from effusions in non-atopic children. In both atopic and non-atopic children, pro-inflammatory cytokines are found at high concentrations. This argues in favor of instituting anti-inflammatory management for treating OME, regardless of atopy.

Revisiting the Electronic Structure of FeS Monomers Using ab Initio Ligand Field Theory and the Angular Overlap Model.

PubMed

Chilkuri, Vijay Gopal; DeBeer, Serena; Neese, Frank

2017-09-05

Iron-sulfur (FeS) proteins are universally found in nature with actives sites ranging in complexity from simple monomers to multinuclear sites from two up to eight iron atoms. These sites include mononuclear (rubredoxins), dinuclear (ferredoxins and Rieske proteins), trinuclear (e.g., hydrogenases), and tetranuclear (various ferredoxins and high-potential iron-sulfur proteins). The electronic structure of the higher-nuclearity clusters is inherently extremely complex. Hence, it is reasonable to take a bottom-up approach in which clusters of increasing nuclearity are analyzed in terms of the properties of their lower nuclearity constituents. In the present study, the first step is taken by an in-depth analysis of mononuclear FeS systems. Two different FeS molecules with phenylthiolate and methylthiolate as ligands are studied in their oxidized and reduced forms using modern wave function-based ab initio methods. The ab initio electronic spectra and wave function are presented and analyzed in detail. The very intricate electronic structure-geometry relationship in these systems is analyzed using ab initio ligand field theory (AILFT) in conjunction with the angular overlap model (AOM) parametrization scheme. The simple AOM model is used to explain the effect of geometric variations on the electronic structure. Through a comparison of the ab initio computed UV-vis absorption spectra and the available experimental spectra, the low-energy part of the many-particle spectrum is carefully analyzed. We show ab initio calculated magnetic circular dichroism spectra and present a comparison with the experimental spectrum. Finally, AILFT parameters and the ab initio spectra are compared with those obtained experimentally to understand the effect of the increased covalency of the thiolate ligands on the electronic structure of FeS monomers.

Risk factors for chronic and recurrent otitis media-a meta-analysis.

PubMed

Zhang, Yan; Xu, Min; Zhang, Jin; Zeng, Lingxia; Wang, Yanfei; Zheng, Qing Yin

2014-01-01

Risk factors associated with chronic otitis media (COM) and recurrent otitis media (ROM) have been investigated in previous studies. The objective of this study was to integrate the findings and determine the possible risk factors for COM/ROM based on our meta-analysis. A comprehensive search of electronic bibliographic databases (PubMed, Embase, CNKI and Wanfang database) from 1964 to Dec 2012, as well as a manual search of references of articles, was performed. A total of 2971 articles were searched, and 198 full-text articles were assessed for eligibility; 24 studies were eligible for this meta-analysis. Regarding risk factors for COM/ROM, there were two to nine different studies from which the odds ratios (ORs) could be pooled. The presence of allergy or atopy increased the risk of COM/ROM (OR, 1.36; 95% CI, 1.13-1.64; P = 0.001). An upper respiratory tract infection (URTI) significantly increased the risk of COM/ROM (OR, 6.59; 95% CI, 3.13-13.89; P<0.00001). Snoring appeared to be a significant risk factor for COM/ROM (OR, 1.96; 95% CI, 1.78-2.16; P<0.00001). A patient history of acute otitis media (AOM)/ROM increased the risk of COM/ROM (OR, 11.13; 95% CI, 1.06-116.44; P = 0.04). Passive smoke significantly increased the risk of COM/ROM (OR, 1.39; 95% CI, 1.02-1.89 P = 0.04). Low social status appeared to be a risk factor for COM/ROM (OR, 3.82; 95% CI, 1.11-13.15; P = 0.03). Our meta-analysis identified reliable conclusions that allergy/atopy, URTI, snoring, previous history of AOM/ROM, Second-hand smoke and low social status are important risk factors for COM/ROM. Other unidentified risk factors need to be identified in further studies with critical criteria.

Risk Factors for Chronic and Recurrent Otitis Media–A Meta-Analysis

PubMed Central

Zhang, Yan; Xu, Min; Zhang, Jin; Zeng, Lingxia; Wang, Yanfei; Zheng, Qing Yin

2014-01-01

Risk factors associated with chronic otitis media (COM) and recurrent otitis media (ROM) have been investigated in previous studies. The objective of this study was to integrate the findings and determine the possible risk factors for COM/ROM based on our meta-analysis. A comprehensive search of electronic bibliographic databases (PubMed, Embase, CNKI and Wanfang database) from 1964 to Dec 2012, as well as a manual search of references of articles, was performed. A total of 2971 articles were searched, and 198 full-text articles were assessed for eligibility; 24 studies were eligible for this meta-analysis. Regarding risk factors for COM/ROM, there were two to nine different studies from which the odds ratios (ORs) could be pooled. The presence of allergy or atopy increased the risk of COM/ROM (OR, 1.36; 95% CI, 1.13–1.64; P = 0.001). An upper respiratory tract infection (URTI) significantly increased the risk of COM/ROM (OR, 6.59; 95% CI, 3.13–13.89; P<0.00001). Snoring appeared to be a significant risk factor for COM/ROM (OR, 1.96; 95% CI, 1.78–2.16; P<0.00001). A patient history of acute otitis media (AOM)/ROM increased the risk of COM/ROM (OR, 11.13; 95% CI, 1.06–116.44; P = 0.04). Passive smoke significantly increased the risk of COM/ROM (OR, 1.39; 95% CI, 1.02–1.89 P = 0.04). Low social status appeared to be a risk factor for COM/ROM (OR, 3.82; 95% CI, 1.11–13.15; P = 0.03). Our meta-analysis identified reliable conclusions that allergy/atopy, URTI, snoring, previous history of AOM/ROM, Second-hand smoke and low social status are important risk factors for COM/ROM. Other unidentified risk factors need to be identified in further studies with critical criteria. PMID:24466073

Asynchronous RTK precise DGNSS positioning method for deriving a low-latency high-rate output

NASA Astrophysics Data System (ADS)

Liang, Zhang; Hanfeng, Lv; Dingjie, Wang; Yanqing, Hou; Jie, Wu

2015-07-01

Low-latency high-rate (1 Hz) precise real-time kinematic (RTK) can be applied in high-speed scenarios such as aircraft automatic landing, precise agriculture and intelligent vehicle. The classic synchronous RTK (SRTK) precise differential GNSS (DGNSS) positioning technology, however, is not able to obtain a low-latency high-rate output for the rover receiver because of long data link transmission time delays (DLTTD) from the reference receiver. To overcome the long DLTTD, this paper proposes an asynchronous real-time kinematic (ARTK) method using asynchronous observations from two receivers. The asynchronous observation model (AOM) is developed based on undifferenced carrier phase observation equations of the two receivers at different epochs with short baseline. The ephemeris error and atmosphere delay are the possible main error sources on positioning accuracy in this model, and they are analyzed theoretically. In a short DLTTD and during a period of quiet ionosphere activity, the main error sources decreasing positioning accuracy are satellite orbital errors: the "inverted ephemeris error" and the integration of satellite velocity error which increase linearly along with DLTTD. The cycle slip of asynchronous double-differencing carrier phase is detected by TurboEdit method and repaired by the additional ambiguity parameter method. The AOM can deal with synchronous observation model (SOM) and achieve precise positioning solution with synchronous observations as well, since the SOM is only a specific case of AOM. The proposed method not only can reduce the cost of data collection and transmission, but can also support the mobile phone network data link transfer mode for the data of the reference receiver. This method can avoid data synchronizing process besides ambiguity initialization step, which is very convenient for real-time navigation of vehicles. The static and kinematic experiment results show that this method achieves 20 Hz or even higher rate output in real time. The ARTK positioning accuracy is better and more robust than the combination of phase difference over time (PDOT) and SRTK method at a high rate. The ARTK positioning accuracy is equivalent to SRTK solution when the DLTTD is 0.5 s, and centimeter level accuracy can be achieved even when DLTTD is 15 s.

Rapidly cycling Lgr5+ stem cells are exquisitely sensitive to extrinsic dietary factors that modulate colon cancer risk.

PubMed

Kim, Eunjoo; Davidson, Laurie A; Zoh, Roger S; Hensel, Martha E; Salinas, Michael L; Patil, Bhimanagouda S; Jayaprakasha, Guddadarangavvanahally K; Callaway, Evelyn S; Allred, Clinton D; Turner, Nancy D; Weeks, Brad R; Chapkin, Robert S

2016-11-10

The majority of colon tumors are driven by aberrant Wnt signaling in intestinal stem cells, which mediates an efficient route toward initiating intestinal cancer. Natural lipophilic polyphenols and long-chain polyunsaturated fatty acids (PUFAs) generally suppress Wnt- and NF-κB- (nuclear factor-κ light-chain enhancer of activated B-cell) related pathways. However, the effects of these extrinsic agents on colonic leucine-rich repeat-containing G-protein-coupled receptor 5-positive (Lgr5 + ) stem cells, the cells of origin of colon cancer, have not been documented to date. Therefore, we examined the effect of n-3 PUFA and polyphenol (curcumin) combination on Lgr5 + stem cells during tumor initiation and progression in the colon compared with an n-6 PUFA-enriched control diet. Lgr5-EGFP-IRES- creERT2 knock-in mice were fed diets containing n-6 PUFA (control), n-3 PUFA, n-6 PUFA+curcumin or n-3 PUFA+curcumin for 3 weeks, followed by 6 azoxymethane (AOM) injections, and terminated 17 weeks after the last injection. To further elucidate the effects of the dietary bioactives at the tumor initiation stage, Lgr5 + stem cells were also assessed at 12 and 24 h post AOM injection. Only n-3 PUFA+curcumin feeding reduced nuclear β-catenin in aberrant crypt foci (by threefold) compared with control at the progression time point. n-3 PUFA+curcumin synergistically increased targeted apoptosis in DNA-damaged Lgr5 + stem cells by 4.5-fold compared with control at 12 h and maximally reduced damaged Lgr5 + stem cells at 24 h, down to the level observed in saline-treated mice. Finally, RNAseq analysis indicated that p53 signaling in Lgr5 + stem cells from mice exposed to AOM was uniquely upregulated only following n-3 PUFA+curcumin cotreatment. These novel findings demonstrate that Lgr5 + stem cells are uniquely responsive to external dietary cues following the induction of DNA damage, providing a therapeutic strategy for eliminating damaged Lgr5 + stem cells to reduce colon cancer initiation.

Rapidly cycling Lgr5+ stem cells are exquisitely sensitive to extrinsic dietary factors that modulate colon cancer risk

PubMed Central

Kim, Eunjoo; Davidson, Laurie A; Zoh, Roger S; Hensel, Martha E; Salinas, Michael L; Patil, Bhimanagouda S; Jayaprakasha, Guddadarangavvanahally K; Callaway, Evelyn S; Allred, Clinton D; Turner, Nancy D; Weeks, Brad R; Chapkin, Robert S

2016-01-01

The majority of colon tumors are driven by aberrant Wnt signaling in intestinal stem cells, which mediates an efficient route toward initiating intestinal cancer. Natural lipophilic polyphenols and long-chain polyunsaturated fatty acids (PUFAs) generally suppress Wnt- and NF-κB- (nuclear factor-κ light-chain enhancer of activated B-cell) related pathways. However, the effects of these extrinsic agents on colonic leucine-rich repeat-containing G-protein-coupled receptor 5-positive (Lgr5+) stem cells, the cells of origin of colon cancer, have not been documented to date. Therefore, we examined the effect of n-3 PUFA and polyphenol (curcumin) combination on Lgr5+ stem cells during tumor initiation and progression in the colon compared with an n-6 PUFA-enriched control diet. Lgr5-EGFP-IRES-creERT2 knock-in mice were fed diets containing n-6 PUFA (control), n-3 PUFA, n-6 PUFA+curcumin or n-3 PUFA+curcumin for 3 weeks, followed by 6 azoxymethane (AOM) injections, and terminated 17 weeks after the last injection. To further elucidate the effects of the dietary bioactives at the tumor initiation stage, Lgr5+ stem cells were also assessed at 12 and 24 h post AOM injection. Only n-3 PUFA+curcumin feeding reduced nuclear β-catenin in aberrant crypt foci (by threefold) compared with control at the progression time point. n-3 PUFA+curcumin synergistically increased targeted apoptosis in DNA-damaged Lgr5+ stem cells by 4.5-fold compared with control at 12 h and maximally reduced damaged Lgr5+ stem cells at 24 h, down to the level observed in saline-treated mice. Finally, RNAseq analysis indicated that p53 signaling in Lgr5+ stem cells from mice exposed to AOM was uniquely upregulated only following n-3 PUFA+curcumin cotreatment. These novel findings demonstrate that Lgr5+ stem cells are uniquely responsive to external dietary cues following the induction of DNA damage, providing a therapeutic strategy for eliminating damaged Lgr5+ stem cells to reduce colon cancer initiation. PMID:27831561

Cost-effectiveness analysis of 10- and 13-valent pneumococcal conjugate vaccines in Peru.

PubMed

Mezones-Holguin, Edward; Canelo-Aybar, Carlos; Clark, Andrew David; Janusz, Cara Bess; Jaúregui, Bárbara; Escobedo-Palza, Seimer; Hernandez, Adrian V; Vega-Porras, Denhiking; González, Marco; Fiestas, Fabián; Toledo, Washington; Michel, Fabiana; Suárez, Víctor J

2015-05-07

To evaluate the cost-effectiveness of introducing the 10-valent pneumococcal conjugate vaccine (PCV10) versus the 13-valent PCV (PCV13) to the National Immunization Schedule in Peru for prevention of pneumococcal disease (PD) in children <5 years of age. The integrated TRIVAC vaccine cost-effectiveness model from the Pan American Health Organization's ProVac Initiative (version 2.0) was applied from the perspective of the Government of Peru. Twenty successive cohorts of children from birth to 5 years were evaluated. Clinical outcomes were pneumococcal pneumonia (PP), pneumococcal meningitis (PM), pneumococcal sepsis (PS) and acute otitis media from any causes (AOM). Measures included prevention of cases, neurological sequelae (NS), auditory sequelae (AS), deaths and disability adjusted life years (DALYs). A sensitivity analyses was also performed. For the 20 cohorts, net costs with PCV10 and PCV13 were US$ 363.26 million and US$ 408.26 million, respectively. PCV10 prevented 570,273 AOM; 79,937 PP; 2217 PM; 3049 PS; 282 NS; 173 AS; and 7512 deaths. PCV13 prevented 419,815 AOM; 112,331 PN; 3116 PM; 4285 PS; 404 NS; 248 AS; and 10,386 deaths. Avoided DALYs were 226,370 with PCV10 and 313,119 with PCV13. Saved treatment costs were US$ 37.39 million with PCV10 and US$ 47.22 million with PCV13. Costs per DALY averted were US$ 1605 for PCV10, and US$ 1304 for PCV13. Sensitivity analyses showed similar results. PCV13 has an extended dominance over PCV10. Both pneumococcal vaccines are cost effective in the Peruvian context. Although the net cost of vaccination with PCV10 is lower, PCV13 prevented more deaths, pneumococcal complications and sequelae. Costs per each prevented DALY were lower with PCV13. Thus, PCV13 would be the preferred policy; PCV10 would also be reasonable (and cost-saving relative to the status quo) if for some reason 13-valent were not feasible. Copyright © 2015. Published by Elsevier Ltd.

Authigenic carbonates from active methane seeps offshore southwest Africa

NASA Astrophysics Data System (ADS)

Pierre, Catherine; Blanc-Valleron, Marie-Madeleine; Demange, Jérôme; Boudouma, Omar; Foucher, Jean-Paul; Pape, Thomas; Himmler, Tobias; Fekete, Noemi; Spiess, Volkhard

2012-12-01

The southwest African continental margin is well known for occurrences of active methane-rich fluid seeps associated with seafloor pockmarks at water depths ranging broadly from the shelf to the deep basins, as well as with high gas flares in the water column, gas hydrate accumulations, diagenetic carbonate crusts and highly diverse benthic faunal communities. During the M76/3a expedition of R/V METEOR in 2008, gravity cores recovered abundant authigenic carbonate concretions from three known pockmark sites—Hydrate Hole, Worm Hole, the Regab pockmark—and two sites newly discovered during that cruise, the so-called Deep Hole and Baboon Cluster. The carbonate concretions were commonly associated with seep-benthic macrofauna and occurred within sediments bearing shallow gas hydrates. This study presents selected results from a comprehensive analysis of the mineralogy and isotope geochemistry of diagenetic carbonates sampled at these five pockmark sites. The oxygen isotope stratigraphy obtained from three cores of 2-5 m length indicates a maximum age of about 60,000-80,000 years for these sediments. The authigenic carbonates comprise mostly magnesian calcite and aragonite, associated occasionally with dolomite. Their very low carbon isotopic compositions (-61.0 < δ13C ‰ V-PDB < -40.1) suggest anaerobic oxidation of methane (AOM) as the main process controlling carbonate precipitation. The oxygen isotopic signatures (+2.4 < δ18O ‰ V-PDB < +6.2) lie within the range in equilibrium under present-day/interglacial to glacial conditions of bottom seawater; alternatively, the most positive δ18O values might reflect the contribution of 18O-rich water from gas hydrate decomposition. The frequent occurrence of diagenetic gypsum crystals suggests that reduced sulphur (hydrogen sulphide, pyrite) from sub-seafloor sediments has been oxidized by oxygenated bottom water. The acidity released during this process can potentially induce the dissolution of carbonate, thereby providing enough Ca2+ ions for pore solutions to reach gypsum saturation; this is thought to be promoted by the bio-irrigation and burrowing activity of benthic fauna. The δ18O-δ13C patterns identified in the authigenic carbonates are interpreted to reflect variations in the rate of AOM during the last glacial-interglacial cycle, in turn controlled by variably strong methane fluxes through the pockmarks. These results complement the conclusions of Kasten et al. in this special issue, based on authigenic barite trends at the Hydrate Hole and Worm Hole pockmarks which were interpreted to reflect spatiotemporal variations in AOM related to subsurface gas hydrate formation-decomposition.

Modeling the cost-effectiveness of infant vaccination with pneumococcal conjugate vaccines in Germany.

PubMed

Kuhlmann, Alexander; von der Schulenburg, J-Matthias Graf

2017-04-01

In 2009, the European Medicines Agency granted approval for two higher-valent pneumococcal conjugate vaccines. This study aims to evaluate the cost-effectiveness of universal infant (<2 years old) vaccination with a 13-valent pneumococcal conjugate vaccine (PCV13) in comparison with a 10-valent pneumococcal conjugate vaccine (PCV10) for the prevention of pneumococcal disease in Germany. A population-based Markov model was developed to estimate the impact of PCV13 and PCV10 on invasive pneumococcal disease (IPD), non-invasive pneumonia (PNE), and acute otitis media (AOM) over a time horizon of 50 years. The model included the effects of the historical vaccination scheme in infants as well as indirect herd effects and replacement disease. We used German epidemiological data to calculate episodes of IPD, PNE, and AOM, as well as direct and indirect effects of the vaccination. Parameter uncertainty was tested in univariate and probabilistic sensitivity analyses. In the base-case analysis, the ICER of PCV13 versus PCV10 infant vaccination was EUR 9826 per quality-adjusted life-year (QALY) gained or EUR 5490 per life-year (LY) gained from the societal perspective and EUR 3368 per QALY gained or EUR 1882 per LY gained from the perspective of the German statutory health insurance. The results were particularly sensitive to the magnitude of indirect effects of both vaccines. Universal infant vaccination with PCV13 is likely to be a cost-effective intervention compared with PCV10 within the German health care system, if additional net indirect effects of PCV13 vaccination are significant.

The influence of algal organic matter produced by Microcystis aeruginosa on coagulation-ultrafiltration treatment of natural organic matter.

PubMed

Xu, Jie; Zhao, Yanxia; Gao, Baoyu; Han, Songlin; Zhao, Qian; Liu, Xiaoli

2018-04-01

Cyanobacterial bloom causes the release of algal organic matter (AOM), which inevitably affects the treatment processes of natural organic matter (NOM). This study works on treating micro-polluted surface water (SW) by emerging coagulant, namely titanium sulfate (Ti(SO 4 ) 2 ), followed by Low Pressure Ultrafiltration (LPUF) technology. In particular, we explored the respective influence of extracellular organic matter (EOM) and intracellular organic matter (IOM) on synergetic EOM-NOM/IOM-NOM removal, functional mechanisms and subsequent filtration performance. Results show that the IOM inclusion in surface water body facilitated synergic IOM-NOM composite pollutants removal by Ti(SO 4 ) 2 , wherein loosely-aggregated flocs were produced, resulting in floc cake layer with rich porosity and permeability during LPUF. On the contrary, the surface water invaded by EOM pollutants increased Ti(SO 4 ) 2 coagulation burden, with substantially deteriorated both UV 254 -represented and dissolved organic matter (DOC) removal. Corresponded with the weak Ti(SO 4 ) 2 coagulation for EOM-NOM removal was the resultant serious membrane fouling during LPUF procedure, wherein dense cake layer was formed due to the compact structure of flocs. Although the IOM enhanced NOM removal with reduced Ti(SO 4 ) 2 dose and yielded mitigated membrane fouling, larger percentage of irreversible fouling was seen than NOM and EOM-NOM cases, which was most likely due to the substances with small molecular weight, such as microcystin, adhering in membrane pores. This research would provide theoretical basis for dose selection and process design during AOM-NOM water treatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Natural dietary compound naringin prevents azoxymethane/dextran sodium sulfate-induced chronic colorectal inflammation and carcinogenesis in mice.

PubMed

Zhang, Yu-Sheng; Wang, Feng; Cui, Shu-Xiang; Qu, Xian-Jun

2018-03-26

Naringin, a natural occurring flavonoid compound, enriches in citrus fruits. We aimed to evaluate the inhibitory effect of naringin on colitis and chronic inflammation-driven carcinogenesis. Male C57BL/6 mice were exposed to AOM/DSS to induce colorectal inflammation and carcinogenesis. Naringin by oral administration prevented AOM/DSS-induced ulcerative colitis and carcinogenesis without significant side effects. Naringin attenuated the severity of colitis and colorectal adenomas through inhibiting myeloid-derived suppressor cells (MDSCs), pro-inflammatory mediators GM-CSF/M-CSF, IL-6 and TNF-α and the NF-κB/IL-6/STAT3 cascades in colorectal tissues. Naringin-treated mice exhibited normalized structures of colorectal tissues. Electron microscopy analysis showed the suppression of robust endoplasmic reticulum (ER) stress-induced autophagy. Naringin inhibited the secretion of the ER-spanning transmembrane proteins, such as GRP78 ATF6, IRE1α and activated PERK phosphorylated eIF-2α and complex of autophagosomes ATG3, ATG5, ATG7, ATG12, ATG16 and ATG16L1 in the colorectal mucosal cells. Naringin prevented colitis and colorectal carcinogenesis through suppressing robust ER stress-induced autophagy in colorectal mucosal cells. Naringin could develop a promising therapeutic agent for the prevention of ulcerative colitis and colorectal tumor.

Exploring the acceptability of the available pneumococcal conjugate vaccines in Canadian health care professionals and immunization experts.

PubMed

Berman, Melissa; Dubé, Eve; Quach, Caroline

2017-06-05

In children, the 13 and 10-valent pneumoccocal conjugate vaccines (PCV13/10) are currently approved for the prevention of invasive pneumococcal disease (IPD). Acceptability is a key consideration in the implementation of a vaccine program and it is recognized that health professional's attitudes and opinions towards vaccines are independent predictors of the success of an immunization program. We aimed to survey the beliefs and attitudes for the two available PCVs in health care professionals and immunization experts. We interviewed 21 members of Canadian immunization committees and/or participants working in frontline healthcare delivery. Overall, participants predominantly preferred PCV-13 over PCV10. For most, AOM should not be taken into considerations in decisions for pneumococcal vaccination programs implementation. AOM was considered an important endpoint of the program but an ineffective measure of program success due to the lack of surveillance for the condition. Recent evidence pertaining to PCV10 cross-protection against 19A did not affect preference but had an impact on perceptions regarding pricing. To consider implementing any changes to the current program, most participants would require more evidence regarding PCV10 cross-protection and effectiveness against OM. Decreasing vaccine price was cited as a positive outcome of funding both vaccines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spectroscopic properties of K 5Li 2UF 10

NASA Astrophysics Data System (ADS)

Karbowiak, M.; Gajek, Z.; Drożdżyński, J.

2005-04-01

A new uranium (III) fluoro-complex of the formula K 5Li 2UF 10 has been synthesised and characterised by X-ray powder diffraction and electronic absorption spectra measurements. The compound crystallises in the orthorhombic system, space group Pnma, with a = 20.723, b = 7.809, c = 6.932 Å, V = 1121.89 Å 3, Z = 4 and is isostructural with its K 5Li 2NdF 10 and K 5Li 2LaF 10 analogous. The absorption spectrum of a polycrystalline sample of K 5Li 2UF 10 was recorded at 4.2 K in the 3500-45,000 cm -1 range and is discussed. The observed crystal-field levels were assigned and fitted to parameters of the simplified angular overlap model (AOM) and next to those of a semi-empirical Hamiltonian, which was representing the combined atomic and one-electron crystal-field interactions. The starting values of the AOM parameters were obtained from ab initio calculations. The analysis of the spectra enabled the assignment of 71 crystal-field levels of U 3+ with a relatively small r.m.s. deviation of 37 cm -1. The total splitting of 714 cm -1 was calculated for the 4I 9/2 ground multiplet.

Arsenic and chromium in drinking water promote tumorigenesis in a mouse colitis-associated colorectal cancer model and the potential mechanism is ROS-mediated Wnt/β-catenin signaling pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Xin; Mandal, Ardhendu K.; Saito, Hiroshi

2012-07-01

Exposure to carcinogenic metals, such as trivalent arsenic [As(III)] and hexavalent chromium [Cr(VI)], through drinking water is a major global public health problem and is associated with various cancers. However, the mechanism of their carcinogenicity remains unclear. In this study, we used azoxymethane/dextran sodium sulfate (AOM/DSS)-induced mouse colitis-associated colorectal cancer model to investigate their tumorigenesis. Our results demonstrate that exposure to As(III) or Cr(VI), alone or in combination, together with AOM/DSS pretreatment has a promotion effect, increasing the colorectal tumor incidence, multiplicity, size, and grade, as well as cell inflammatory response. Two-dimensional differential gel electrophoresis coupled with mass spectrometry revealedmore » that As(III) or Cr(VI) treatment alone significantly changed the density of proteins. The expression of β-catenin and phospho-GSK was increased by treatment of carcinogenic metals alone. Concomitantly, the expression of NADPH oxidase1 (NOX1) and the level of 8-OHdG were also increased by treatment of carcinogenic metals alone. Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, were decreased. Similarly, in an in vitro system, exposure of CRL-1807 to carcinogenic metals increased reactive oxygen species (ROS) generation, the expression of β-catenin, phospho-GSK, and NOX1. Inhibition of ROS generation by addition of SOD or catalase inhibited β-catenin expression and activity. Our study provides a new animal model to study the carcinogenicity of As(III) and Cr(VI) and suggests that As(III) and Cr(VI) promote colorectal cancer tumorigenesis, at least partly, through ROS-mediated Wnt/β-catenin signaling pathway. -- Highlights: ► Carcinogenic metals in drinking water promote colorectal tumor formation in vivo. ► Carcinogenic metals induce β-catenin activation in vivo and in vitro. ► ROS generation induced by carcinogenic metals mediated β-catenin activation.« less

AOM reconciling of crystal field parameters for UCl 3, UBr 3, UI 3 series

NASA Astrophysics Data System (ADS)

Gajek, Z.; Mulak, J.

1990-07-01

Available inelastic neutron scattering interpretations of crystal field effect in the uranium trihalides have been verified in terms of Angular Overlap Model. For UCl 3 a good reconciling of both INS and optical interpretations of crystal field effect has been obtained. On the contrary, the parameterizations for UBr 3 and UI 3 were found to be highly artificial and suggestion is given to experimentalists to reinterpret their INS spectra.

Saturated CO2 inhibits microbial processes in CO2-vented deep-sea sediments

NASA Astrophysics Data System (ADS)

de Beer, D.; Haeckel, M.; Neumann, J.; Wegener, G.; Inagaki, F.; Boetius, A.

2013-02-01

This study focused on biogeochemical processes and microbial activity in sediments of a natural deep-sea CO2 seepage area (Yonaguni Knoll IV hydrothermal system, Japan). The aim was to assess the influence of the geochemical conditions occurring in highly acidic and CO2 saturated sediments on sulphate reduction (SR) and anaerobic methane oxidation (AOM). Porewater chemistry was investigated from retrieved sediment cores and in situ by microsensor profiling. The sites sampled around a sediment-hosted hydrothermal CO2 vent were very heterogeneous in porewater chemistry, indicating a complex leakage pattern. Near the vents, droplets of liquid CO2 were observed to emanate from the sediments, and the pH reached approximately 4.5 in a sediment depth >6 cm, as determined in situ by microsensors. Methane and sulphate co-occurred in most sediment samples from the vicinity of the vents down to a depth of at least 3 m. However, SR and AOM were restricted to the upper 7-15 cm below seafloor, although neither temperature, low pH, nor the availability of methane and sulphate could be limiting microbial activity. We argue that the extremely high subsurface concentrations of dissolved CO2 (1000-1700 mM), through the ensuing high H2CO3 levels (approx. 1-2 mM) uncouples the proton-motive-force (PMF) and thus inhibits biological energy conservation by ATPase-driven phosphorylation. This limits life to the surface sediment horizons above the liquid CO2 phase, where less extreme conditions prevail. Our results may have to be taken into consideration in assessing the consequences of deep-sea CO2 sequestration on benthic element cycling and on the local ecosystem state.

Intracranial venous sinus thrombosis as a complication of otitis media in children: Critical review of diagnosis and management.

PubMed

Zanoletti, Elisabetta; Cazzador, Diego; Faccioli, Chiara; Sari, Marianna; Bovo, Roberto; Martini, Alessandro

2015-12-01

Otogenic lateral sinus thrombosis (LST) is a rare intracranial complication of acute otitis media (AOM), which can lead to severe neurological sequelae and death. The aim of this study was to analyze the clinical presentation, management and outcome of LST in children, investigating a possible correlation between clinical aspects, radiological findings and anatomical variations. At a tertiary Italian hospital, a retrospective review was conducted on the medical records of eight patients diagnosed with otogenic LST over a 3-year period. Four children were males and mean age was 4.7 years. All patients had a history of otitis media at diagnosis and 4/8 presented also with more than one neurological sign or symptom. Mastoiditis signs were detected in 5/8 patients. Thrombosis was diagnosed by computed tomography, enhanced magnetic resonance and magnetic resonance venography. Treatment was medical, alone or combined with surgery. Medical treatment consisted in anticoagulants eventually combined with anti-edema medication on clinical basis. Mastoidectomy and/or myringotomy±trans-tympanic drainage placement were performed in 7/8 patients. Complete vessel recanalization was obtained in 6/8 children after a median follow-up time of 4.8 months. No complications, neither clinical sequelae occurred. In our series, neurological signs and symptoms were significantly associated with the presence of hypoplasia of the contralateral venous sinus (p=0.029). LST is a severe condition occurring even in absence of otological signs, and despite adequate antibiotic therapy for AOM, which should be ruled out and promptly treated. A dominant neurological presentation is associated in our series with anatomical variations of cerebral sinus venous drainage patterns. This should be carefully evaluated and considered in diagnosis, treatment planning and prognosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Contribution of deep sourced carbon from hydrocarbon seeps to sedimentary organic carbon: Evidence from Δ14C and δ13C isotopes

NASA Astrophysics Data System (ADS)

Feng, D.; Peckmann, J.; Peng, Y.; Liang, Q.; Roberts, H. H.; Chen, D.

2017-12-01

Sulfate-driven anaerobic oxidation of methane (AOM) limits the release of methane from marine sediments and promotes the formation of carbonates close to the seafloor along continental margins. It has been established that hydrocarbon seeps are a source of dissolved inorganic and organic carbon to marine environments. However, questions remain about the contribution of deep sourced carbon from hydrocarbon seeps to the sedimentary organic carbon pool. For a number of hydrocarbon seeps from the South China Sea and the Gulf of Mexico, the portion of modern carbon was determined based on natural radiocarbon abundances (Δ14C) and stable carbon isotope (δ13Corganic carbon) compositions of the non-carbonate fractions extracted from authigenic carbonates. Samples from both areas show a mixing trend between ideal planktonic organic carbon (δ13C = -22‰ VPDB and 90% modern carbon) and the ambient methane. The δ13Corganic carbon values of non-carbonate fractions from three ancient seep deposits (northern Italy, Miocene; western Washington State, USA, Eocene to Oligocene) confirm that the proxy can be used to constrain the record of sulfate-driven AOM through most of Earth history by measuring the δ13C values of organic carbon. This study reveals the potential of using δ13C values of organic carbon to discern seep and non-seep environments. This new approach is particularly promising when authigenic carbonate is not present in ancient sedimentary environments. Acknowledgments: The authors thank BOEM and NOAA for their years' support of the deep-sea dives. Funding was provided by the NSF of China (Grants: 41422602 and 41373085).

Trends in broad-spectrum antibiotic prescribing for children with acute otitis media in the United States, 1998–2004

PubMed Central

Coco, Andrew S; Horst, Michael A; Gambler, Angela S

2009-01-01

Background Overuse of broad-spectrum antibiotics is associated with antibiotic resistance. Acute otitis media (AOM) is responsible for a large proportion of antibiotics prescribed for US children. Rates of broad-spectrum antibiotic prescribing for AOM are unknown. Methods Analysis of the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, 1998 to 2004 (N = 6,878). Setting is office-based physicians, hospital outpatient departments, and emergency departments. Patients are children aged 12 years and younger prescribed antibiotics for acute otitis media. Main outcome measure is percentage of broad-spectrum antibiotics, defined as amoxicillin/clavulanate, macrolides, cephalosporins and quinolones. Results Broad-spectrum prescribing for acute otitis media increased from 34% of visits in 1998 to 45% of visits in 2004 (P < .001 for trend). The trend was primarily attributable to an increase in prescribing of amoxicillin/clavulanate (8% to 15%; P < .001 for trend) and macrolides (9% to 15%; P < .001 for trend). Prescribing remained stable for amoxicillin and cephalosporins while decreasing for narrow-spectrum agents (12% to 3%; P < .001 for trend) over the study period. Independent predictors of broad-spectrum antibiotic prescribing were ear pain, non-white race, public and other insurance (compared to private), hospital outpatient department setting, emergency department setting, and West region (compared to South and Midwest regions), each of which was associated with lower rates of broad-spectrum prescribing. Age and fever were not associated with prescribing choice. Conclusion Prescribing of broad-spectrum antibiotics for acute otitis media has steadily increased from 1998 to 2004. Associations with non-clinical factors suggest potential for improvement in prescribing practice. PMID:19552819

Yerba mate tea and mate saponins prevented azoxymethane-induced inflammation of rat colon through suppression of NF-kB p65ser(311) signaling via IkB-a and GSK-3ß reduced phosphorylation

USDA-ARS?s Scientific Manuscript database

Yerba mate tea (YMT) has a chemopreventive role in a variety of inflammatory diseases. The objective was to determine the capability of YMT and mate saponins to prevent azoxymethane (AOM)-induced colonic inflammation in rats. YMT (2% dry leaves, w/v, as a source of drinking fluid) (n = 15) and mat...

Digital Data Acquisition for Laser Radar for Vibration Analysis

DTIC Science & Technology

1998-06-01

and the resulting signal is a function of the relative phase of the two waves , which changes as the target vibrates. The relative phase is inversely...light crosses the medium in a direction perpendicular to the acoustic waves , a modulated optical wave front will result. A standing acoustic wave in the...mean that the frequency can be up or down-shifted, depending on the orientation of the AOM, or the direction of the traveling acoustic waves . An

[The clinical classification of acute otitis media with special reference to tympanometry].

PubMed

Subbotina, M V

We have developed a new clinical classification of acute otitis media (AOM) based on the previously proposed classifications of V.T. Palchun with co-workers (1997) and J. Jeger (1970) in which the letter near the stage of the pathological process roughly corresponds to the type of the tympanogram as follows: stage I (acute tubootitis): A, B, C; stage II (acute catarrhal otitis media): A, B, C; stage III (acute purulent otitis media, perforation stage); stage IV (acute purulent otitis media, post-perforation stage); stage V (resolution of otitis media): A - convalescence or recovery, B1 - exudate present in the tympanic cavity; B2 - persisting perforation; C - block of the auditory tube, O - the development of complications. This classification implies the necessity of tympanometry at the stage of diagnostics of AOM although it is not mandatory because the detection of exudate as a result of paracentesis at any of the stages of otitis media will allow to designate the stage of otitis either by letter A, B or C. The application of the new classification described in this article permits to more accurately than before determine the character of the pathological process in the middle ear during the course of acute otitis media which is of special importance in the clinical pediatric practice for the timely and adequate treatment of the children.

Geochemical, metagenomic and metaproteomic insights into trace metal utilization by methane-oxidizing microbial consortia in sulphidic marine sediments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glass, DR. Jennifer; Yu, DR. Hang; Steele, Joshua

2013-01-01

Microbes have obligate requirements for trace metals in metalloenzymes that catalyse important biogeochemical reactions. In anoxic methane- and sulphiderich environments, microbes may have unique adaptations for metal acquisition and utilization because of decreased bioavailability as a result of metal sulphide precipitation. However, micronutrient cycling is largely unexplored in cold ( 10 C) and sulphidic (> 1 mM H2S) deep-sea methane seep ecosystems. We investigated trace metal geochemistry and microbial metal utilization in methane seeps offshore Oregon and California, USA, and report dissolved concentrations of nickel (0.5 270 nM), cobalt (0.5 6 nM), molybdenum (10 5600 nM) and tungsten (0.3 8more » nM) in Hydrate Ridge sediment porewaters. Despite low levels of cobalt and tungsten, metagenomic and metaproteomic data suggest that microbial consortia catalysing anaerobic oxidation of methane (AOM) utilize both scarce micronutrients in addition to nickel and molybdenum. Genetic machinery for cobalt-containing vitamin B12 biosynthesis was present in both anaerobic methanotrophic archaea (ANME) and sulphate-reducing bacteria. Proteins affiliated with the tungsten-containing form of formylmethanofuran dehydrogenase were expressed in ANME from two seep ecosystems, the first evidence for expression of a tungstoenzyme in psychrophilic microorganisms. Overall, our data suggest that AOM consortia use specialized biochemical strategies to overcome the challenges of metal availability in sulphidic environments.« less

Depleted δ13C Values in Salt Dome Cap Rock Organic Matter and Implications for Microbial Metabolism and Fixation

NASA Astrophysics Data System (ADS)

Loyd, S. J.; Lu, L.; Caesar, K. H.; Kyle, R.

2015-12-01

Salt domes occur throughout the Gulf Coast Region USA and are often associated with trapped hydrocarbons. These salt domes can be capped by sulfate and carbonate minerals that result from complex digenetic interactions in the subsurface. The specific natures of these interactions are poorly understood, in particular the role of microbes in facilitating mineralization and element cycling. Carbon isotope compositions of cap rock calcites (δ13Ccarb) are highly variable and range from near neutral to less than -40‰ (VPDB) indicative of methane-sourced carbon. These low values and the common coexistence of elemental sulfur and metal sulfides have spurred hypotheses invoking microbial sulfate reduction as driving carbonate mineral authigenesis. Here, we present new organic carbon isotope (δ13Corg) data that, similar to δ13Ccarb, exhibit depletions below -30 to -25‰. These δ13Corg values are lower than local liquid hydrocarbons and "normal" marine organic matter reflecting either microbial fixation of methane-sourced carbon or microbial fractionation from liquid hydrocarbon sources. The combined carbon isotope data (δ13Ccarb and δ13Corg) indicate that methane likely plays an important role in microbial cycling in salt domes. The δ13Corg values are similar to those of anaerobic oxidation of methane (AOM) related communities from methane-sulfate controlled marine sediments. Ultimately, salt dome environments may share some important characteristics with AOM systems.

Circulating DNA and its methylation level in inflammatory bowel disease and related colon cancer.

PubMed

Bai, Xuming; Zhu, Yaqun; Pu, Wangyang; Xiao, Li; Li, Kai; Xing, Chungen; Jin, Yong

2015-01-01

Both of chronic inflammation and abnormal immune in inflammatory bowel disease can induce colon cancer. Previous research showed that cell apoptosis and necrosis become the main source of circulating DNA in the peripheral blood during tumorigenesis that reduced along with methylation degree. However, its role in the process of colitis transforming to colon cancer is not clarified. Drinking 3% DSS was used to establish colitis model, while 3% dextran sodium sulfate (DSS) combined with azo oxidation methane (AOM) intraperitoneal injection was applied to establish colitis related colon cancer model. Circulating DNA and its methylation level in peripheral blood were tested. Morphology observation, HE staining, and p53 and β-catenin expression detection confirmed that drinking 3% DSS and 3% DSS combined with AOM intraperitoneal injection can successfully establish colitis and colitis associated colorectal cancer models. Circulating DNA level in colitis and colon cancer mice increased by gradient compared with control, while significant difference was observed between each other. Circulating DNA methylation level decreased obviously in colitis and colon cancer, and significant difference was observed between each other. Abnormal protein expression, circulating DNA and its methylation level in ulcerative colitis associated colorectal tissues change in gradient, suggesting that circulating DNA and its methylation level can be treated as new markers for colitis cancer transformation that has certain significance to explore the mechanism of human ulcerative colitis canceration.

Electron acceptors for anaerobic oxidation of methane drive microbial community structure and diversity in mud volcanoes.

PubMed

Ren, Ge; Ma, Anzhou; Zhang, Yanfen; Deng, Ye; Zheng, Guodong; Zhuang, Xuliang; Zhuang, Guoqiang; Fortin, Danielle

2018-04-06

Mud volcanoes (MVs) emit globally significant quantities of methane into the atmosphere, however, methane cycling in such environments is not yet fully understood, as the roles of microbes and their associated biogeochemical processes have been largely overlooked. Here, we used data from high-throughput sequencing of microbial 16S rRNA gene amplicons from six MVs in the Junggar Basin in northwest China to quantify patterns of diversity and characterize the community structure of archaea and bacteria. We found anaerobic methanotrophs and diverse sulfate- and iron-reducing microbes in all of the samples, and the diversity of both archaeal and bacterial communities was strongly linked to the concentrations of sulfate, iron and nitrate, which could act as electron acceptors in anaerobic oxidation of methane (AOM). The impacts of sulfate/iron/nitrate on AOM in the MVs were verified by microcosm experiments. Further, two representative MVs were selected to explore the microbial interactions based on phylogenetic molecular ecological networks. The sites showed distinct network structures, key species and microbial interactions, with more complex and numerous linkages between methane-cycling microbes and their partners being observed in the iron/sulfate-rich MV. These findings suggest that electron acceptors are important factors driving the structure of microbial communities in these methane-rich environments. © 2018 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

Persistence of Bacteroides ovatus under simulated sunlight irradiation

PubMed Central

2014-01-01

Background Bacteroides ovatus, a member of the genus Bacteroides, is considered for use in molecular-based methods as a general fecal indicator. However, knowledge on its fate and persistence after a fecal contamination event remains limited. In this study, the persistence of B. ovatus was evaluated under simulated sunlight exposure and in conditions similar to freshwater and seawater. By combining propidium monoazide (PMA) treatment and quantitative polymerase chain reaction (qPCR) detection, the decay rates of B. ovatus were determined in the presence and absence of exogenous photosensitizers and in salinity up to 39.5 parts per thousand at 27°C. Results UVB was found to be important for B. ovatus decay, averaging a 4 log10 of decay over 6 h of exposure without the presence of extracellular photosensitizers. The addition of NaNO2, an exogenous sensitizer producing hydroxyl radicals, did not significantly change the decay rate of B. ovatus in both low and high salinity water, while the exogenous sensitizer algae organic matter (AOM) slowed down the decay of B. ovatus in low salinity water. At seawater salinity, the decay rate of B. ovatus was slower than that in low salinity water, except when both NaNO2 and AOM were present. Conclusion The results of laboratory experiments suggest that if B. ovatus is released into either freshwater or seawater environment in the evening, 50% of it may be intact by the next morning; if it is released at noon, only 50% may be intact after a mere 5 min of full spectrum irradiation on a clear day. This study provides a mechanistic understanding to some of the important environmental relevant factors that influenced the inactivation kinetics of B. ovatus in the presence of sunlight irradiation, and would facilitate the use of B. ovatus to indicate the occurrence of fecal contamination. PMID:24993443

An Evaluation of Sea Turtle Populations and Survival Status on Vieques Island.

DTIC Science & Technology

1982-06-22

Pritchard T. H. Stubbs Florida Audubon Society (N66001-80-C-0560) 22 June 1982 Prepared for Marine Sciences Division Approved for public release...the Florida Audubon Society for NOSC Marine Sciences Division (Code 513). I Released by Under authority of S. Yamamoto. Head H.O. Porter. Head Marine ...Coollco so wo . i .0*W ow a AomY b block4 m.. Reptiles -. HawksbilIVieques Isand Loaesbsd Green turtle Nestn Turtles Loatharback 2 0. AGSTA ACT

The Implementation of a Plant and Minor Property Accounting System for the Naval Postgraduate School.

DTIC Science & Technology

1987-09-01

Autmatic Data Processing iquipment CPU Central Procesing Unit DSA Date lase Administrator USU Data "aso Management system D&XC Defense Automation...ground? -How big is a certain piece of plant property (e.g., for shipment)? 2. Nxnected Data Base Volume The current inventory of NPS plant property...System, Automated Data TU I. 89aom so fg o - e In October 136 the aval Postgraduate School was directed to centralize the accounting and control of

Continuous-Tone Electrostatic Electrography

DTIC Science & Technology

1948-12-15

TRANSLATOR <»>: Schaf fort, R.M. Williams, D.I. WfOiwp, L*E, = TYRS. SERIES . NUMBER AND PERIOD OF R*RO«T COVERED: Quarterly Progress ropt fjT...a passing wire (a ohöft distance abo’ve tho plato) or a series qf point a or othor oourpoo of aom<^> ^mat similar geometry hold at high voltage In... temporale of tho plat©» If tho dark decay i„s not of thermal : origin, an exponential typo of decay would still ho anticipated. Ih such caoe

Impact of natural oil and higher hydrocarbons on microbial diversity, distribution, and activity in Gulf of Mexico cold-seep sediments

NASA Astrophysics Data System (ADS)

Orcutt, Beth N.; Joye, Samantha B.; Kleindienst, Sara; Knittel, Katrin; Ramette, Alban; Reitz, Anja; Samarkin, Vladimir; Treude, Tina; Boetius, Antje

2010-11-01

Gulf of Mexico cold seeps characterized by variable compositions and magnitudes of hydrocarbon seepage were sampled in order to investigate the effects of natural oils, methane, and non-methane hydrocarbons on microbial activity, diversity, and distribution in seafloor sediments. Though some sediments were characterized by relatively high quantities of oil, which may be toxic to some microorganisms, high rates of sulfate reduction (SR, 27.9±14.7 mmol m-2 d-1), anaerobic oxidation of methane (AOM, 16.2±6.7 mmol m-2 d-1), and acetate oxidation (2.74±0.76 mmol m-2 d-1) were observed in radiotracer measurements. In many instances, the SR rate was higher than the AOM rate, indicating that non-methane hydrocarbons fueled SR. Analysis of 16S rRNA gene clone libraries revealed phylogenetically diverse communities that were dominated by phylotypes of sulfate-reducing bacteria (SRB) and anaerobic methanotrophs of the ANME-1 and ANME-2 varieties. Another group of archaea form a Gulf of Mexico-specific clade (GOM ARC2) that may be important in brine-influenced, oil-impacted sediments from deeper water. Additionally, species grouping within the uncultivated Deltaproteobacteria clades SEEP-SRB3 and -SRB4, as well as relatives of Desulfobacterium anilini, were observed in relatively higher abundance in the oil-impacted sediments, suggesting that these groups of SRB may be involved in or influenced by degradation of higher hydrocarbons or petroleum byproducts.

Aragonite precipitation induced by anaerobic oxidation of methane in shallow-water seeps, Tyrrhenian Sea, Italy

NASA Astrophysics Data System (ADS)

Wiedling, Johanna; Kuhfuß, Hanna; Lott, Christian; Böttcher, Michael E.; Lichtschlag, Anna; Wegener, Gunter; Deusner, Christian; Bach, Wolfgang; Weber, Miriam

2014-05-01

In the shallow-water organic-poor silicate sands off the West coast of Elba, Italy, we found aragonite precipitates within a radius of 10 cm to methane seeps in 20 - 40 cm sediment depth. The shallow seep site was mapped by SCUBA diving and in an area of 100 m2 nine gas emission spots were observed. The gas emission, containing 73 Vol. % methane, was measured to be 0.72 L m-2 d-1. Findings of anaerobic methane oxidizing archea (ANME 1, 2, 2a, 2b) and sulphate reducing bacteria (SRB) as well as in vitro rate measurements of anaerobic oxidation of methane (AOM) with a maximum of 67 ± 7 nmol CH4 cm-3 d-1 led to the hypothesis that carbonate precipitation is coupled to these microbial processes. Porewater analysis showed elevated concentrations of dissolved inorganic carbon (DIC) (up to 15.5 mmol L-1) and hydrogen sulfide (up to 6.6 mmol L-1). The presence of bicarbonate and the ambient temperature (14 - 25 ° C) facilitate the precipitation of needle-shaped aragonite. Oxygen isotope compositions of the mineral are consistent with the ambient temperatures and may indicate a recent diagenetic formation of this mineral. Although precipitation should not be preserved in these sandy permeable sediments, influenced by seasonality, wave action, and fluid flow, we found up to 10-50 cm3 irregular pieces of cemented sand grains, very often encrusting dead seagrass rhizomes. Commonly known carbonate structures, especially from the deep sea, are chimneys, mounds, hardgrounds and nodules. These structures are well known from seep and vent sites, usually showing the same range of stable carbon isotope fractionation as the escaping methane. The permeable sediment at the Elba site possibly allows the gas to frequently change its pathway to the sediment surface and thus precipitation can occure at several spots and more irregular than in the reported sites. Preservation of precipitates, however, requires sufficient authigenic aragonite to be formed before fluid dynamics changed the flow path. The Elba aragonites, showed a carbon isotope signature of -14.9o vs. VPDB, mirroring the isotopic signature of the pore-water DIC at this sediment depth. Similar δ13C-compositions of -15.3o were obtained for the discharging methane, giving room for discussion about the origin of the gas. We suppose that AOM is the main driver for aragonite precipitation in the permeable sands at the shallow-water seeps because of (1) very low organic carbon contents (0.5 mg/g) in the sediment, (2) 13C enrichment in the methane gas, (3) elevated DIC concentrations in the pore-water, and (4) AOM in vitro activity. Thus, aragonite precipitates of the seep site near Elba may represent a unique system to study ongoing abiogenic seep carbonate formation at shallow depth as a modern analogue for seep carbonates occurring in the geological record.

Chemical and Molecular Biological Aspects of Alkylhydrazine-Induced Carcinogenesis in Human Cells in Vitro

DTIC Science & Technology

1980-09-01

methylazozy- methanol acetate ( MAMA ), proved to be a potent transformer as well as a carcinogen. The obvious conclusion is that the human cell culture...Negative MMH 62 pg/ml Negative [ AOM Negative at 100 1g/ml Not tested MAMA 3.6 ug/ml 900 2/16’ Tetrazine 50 Ug/ml Positive. No data yet. [j Phenylhydrazine...the tumor incidence data for MAMA is not com-B parable to those of UDMH and Hz. I 11-% C. Conclusion: In our attempts,to correlate toxicity and/or

ESA technology flies on Italian mini-satellite launched from Russia

NASA Astrophysics Data System (ADS)

2000-07-01

Owned by the Italian space agency (ASI) and developed by Carlo Gavazzi with contributions from many other Italian companies, MITA has two tasks to perform: in a circular orbit at 450 km altitude, the mini satellite will carry a cosmic particle detector, while its platform will be tested for the first time as a vehicle for future scientific missions. MITA also carries the MTS-AOMS payload (MicroTechSensor for Attitude and Orbit Measurement System), developed by Astrium in the framework of ESA's Technology Flight Opportunity trial programme. With the Technology Flight Opportunity scheme, funded by its General Studies Programme, ESA intends to provide access to space for European industry's technology products needing in-orbit demonstration to enhance their competitiveness on the space market. This new form of support to the European space industry ties in with ESA's strategy for fostering the competitiveness of European-made technology for eventual commercialisation. In-orbit demonstration is essential if new technologies are to compete on level terms on non-European markets. It thus consolidates strategic investments made by the space industry. The MTS-AOMS is a highly integrated sensor for autonomous attitude and orbit control systems. It combines three functions in one unit: Earth sensing, star sensing and magnetic field sensing. The equipment incorporates an active pixel array sensor and a 2-D fluxgate magnetometer. The aims of the flight are to verify in situ the payload's inherent functions and performance, which cannot be done on the ground, and to assess the behaviour of this type of technology when exposed to the space environment. The Technology Flight Opportunity rule is that ESA funds the launch and integration costs, industry the development and operating costs. According to present planning, two further in-orbit demonstrations funded by this scheme will be carried out between now and January 2001.

Mice deficient in Muc4 are resistant to experimental colitis and colitis-associated colorectal cancer.

PubMed

Das, S; Rachagani, S; Sheinin, Y; Smith, L M; Gurumurthy, C B; Roy, H K; Batra, S K

2016-05-19

MUC4, a large transmembrane mucin normally expressed in the small and large intestine, is differentially expressed during inflammatory and malignant conditions of the colon. However, the expression pattern and the role of MUC4 in colitis and colorectal cancer (CRC) are inconclusive. Therefore, the aim of this study was to understand the role of Muc4 during inflammatory and malignant conditions of the colon. Here, we generated Muc4(-/-) mice and addressed its role in colitis and colitis-associated CRC using dextran sodium sulfate (DSS) and azoxymethane (AOM)-DSS experimental models, respectively. Muc4(-/-) mice were viable, fertile with no apparent defects. Muc4(-/-) mice displayed increased resistance to DSS-induced colitis compared with wild-type (WT) littermates that was evaluated by survival rate, body weight loss, diarrhea and fecal blood score, and histological score. Reduced infiltration of inflammatory cells, that is, CD3(+) lymphocytes and F4/80(+) macrophages was observed in the inflamed mucosa along with reduction in the mRNA levels of inflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α and anti-microbial genes Lysozyme M and SLPI in the colon of Muc4(-/-) mice compared with WT littermates. Compensatory upregulation of Muc2 and Muc3 mucins under basal and DSS treatment conditions partly explains the resistance observed in Muc4(-/-) mice. Accordingly, Muc4(-/-) mice exhibited significantly reduced tumor burden compared with WT mice assessed in a colitis-induced tumor model using AOM/DSS. An increased percentage of Ki67(+) nuclei was observed in the tumors from WT compared with Muc4(-/-) mice suggesting Muc4 to be critical in intestinal cell proliferation during tumorigenesis. Taken together, we conclusively demonstrate for the first time the role of Muc4 in driving intestinal inflammation and inflammation-associated tumorigenesis using a novel Muc4(-/-) mouse model.

Mice deficient in Muc4 are resistant to experimental colitis and colitis-associated colorectal cancer

PubMed Central

Das, S; Rachagani, S; Sheinin, Y; Smith, LM; Gurumurthy, CB; Roy, HK; Batra, SK

2017-01-01

MUC4, a large transmembrane mucin normally expressed in the small and large intestine, is differentially expressed during inflammatory and malignant conditions of the colon. However, the expression pattern and the role of MUC4 in colitis and colorectal cancer (CRC) are inconclusive. Therefore, the aim of this study was to understand the role of Muc4 during inflammatory and malignant conditions of the colon. Here, we generated Muc4−/− mice and addressed its role in colitis and colitis-associated CRC using dextran sodium sulfate (DSS) and azoxymethane (AOM)-DSS experimental models, respectively. Muc4−/− mice were viable, fertile with no apparent defects. Muc4−/− mice displayed increased resistance to DSS-induced colitis compared with wild-type (WT) littermates that was evaluated by survival rate, body weight loss, diarrhea and fecal blood score, and histological score. Reduced infiltration of inflammatory cells, that is, CD3+ lymphocytes and F4/80+ macrophages was observed in the inflamed mucosa along with reduction in the mRNA levels of inflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α and anti-microbial genes Lysozyme M and SLPI in the colon of Muc4−/− mice compared with WT littermates. Compensatory upregulation of Muc2 and Muc3 mucins under basal and DSS treatment conditions partly explains the resistance observed in Muc4−/− mice. Accordingly, Muc4−/− mice exhibited significantly reduced tumor burden compared with WT mice assessed in a colitis-induced tumor model using AOM/DSS. An increased percentage of Ki67+ nuclei was observed in the tumors from WT compared with Muc4−/− mice suggesting Muc4 to be critical in intestinal cell proliferation during tumorigenesis. Taken together, we conclusively demonstrate for the first time the role of Muc4 in driving intestinal inflammation and inflammation-associated tumorigenesis using a novel Muc4−/− mouse model. PMID:26364605

Proteomic Stable Isotope Probing Reveals Biosynthesis Dynamics of Slow Growing Methane Based Microbial Communities

PubMed Central

Marlow, Jeffrey J.; Skennerton, Connor T.; Li, Zhou; Chourey, Karuna; Hettich, Robert L.; Pan, Chongle; Orphan, Victoria J.

2016-01-01

Marine methane seep habitats represent an important control on the global flux of methane. Nucleotide-based meta-omics studies outline community-wide metabolic potential, but expression patterns of environmentally relevant proteins are poorly characterized. Proteomic stable isotope probing (proteomic SIP) provides additional information by characterizing phylogenetically specific, functionally relevant activity in mixed microbial communities, offering enhanced detection through system-wide product integration. Here we applied proteomic SIP to 15NH4+ and CH4 amended seep sediment microcosms in an attempt to track protein synthesis of slow-growing, low-energy microbial systems. Across all samples, 3495 unique proteins were identified, 11% of which were 15N-labeled. Consistent with the dominant anaerobic oxidation of methane (AOM) activity commonly observed in anoxic seep sediments, proteins associated with sulfate reduction and reverse methanogenesis—including the ANME-2 associated methylenetetrahydromethanopterin reductase (Mer)—were all observed to be actively synthesized (15N-enriched). Conversely, proteins affiliated with putative aerobic sulfur-oxidizing epsilon- and gammaproteobacteria showed a marked decrease over time in our anoxic sediment incubations. The abundance and phylogenetic range of 15N-enriched methyl-coenzyme M reductase (Mcr) orthologs, many of which exhibited novel post-translational modifications, suggests that seep sediments provide niches for multiple organisms performing analogous metabolisms. In addition, 26 proteins of unknown function were consistently detected and actively expressed under conditions supporting AOM, suggesting that they play important roles in methane seep ecosystems. Stable isotope probing in environmental proteomics experiments provides a mechanism to determine protein durability and evaluate lineage-specific responses in complex microbial communities placed under environmentally relevant conditions. Our work here demonstrates the active synthesis of a metabolically specific minority of enzymes, revealing the surprising longevity of most proteins over the course of an extended incubation experiment in an established, slow-growing, methane-impacted environmental system. PMID:27199908

Precipitation of ikaite crystals in Antarctic marine sediments: implications from pore water geochemistry

NASA Astrophysics Data System (ADS)

Lu, Z.; Kennedy, H.; Rickaby, R. E.; Georg, B.; Shaw, S.; Lennie, A.; Pancost, R. D.

2008-12-01

Ikaite is a calcium carbonate hexahydrate (CaCO3•6H20) considered to be stable only at low temperatures. It has been found in form of tufa tower at locations where alkaline water mixes with water masses enriched in calcium (e.g. Ikka Fjord, Mono Lake). Large euhedral single crystals of ikaite were also recovered in marine sediments, associated with organic matter degradation, anaerobic oxidation of methane (AOM) and sulfate reduction. The hydration water in the ikaite crystals were demonstrated to record the oxygen isotope composition of the water from which they precipitated. Such a characteristic may allow using ikaite to reconstruct the ice volume in the past. For this purpose, the controls on its precipitation in the sediment column need to be investigated which is the main goal of this study. U.S. Antarctica Program cruise NBP0703 collected two cores with ikaite crystals at Antarctica Peninsula (Bransfield Strait and Firth of Tay). We determined major cation/anion concentrations, dissolved inorganic carbon (DIC) and δ13C composition of DIC in the pore waters in these two cores. Strong organic matter degradation or AOM in both cores results in quick consumption of sulfate in shallow part of the cores (SMT at around 3m).Rapid build-up of DIC is accompanied by the sharp decrease of dissolved calcium in the top 5m. Large variations were observed in δ13CDIC values (-20‰ to +13‰). The δ13C of ikaite in two cores were distinctive from each other (-19‰ and +4‰) corresponding to the DIC pools at different depths. The down core saturation state of the ikaite was modeled in PHREEQC based on the pore water chemistry, and the results are consistent with carbon isotope data, suggesting that these large crystals very likely formed within a narrow depth interval and a short time period (given high sedimentation rates of 0.5-1 cm/yr in this area).

Mortality characteristics of aortic root surgery in North America†

PubMed Central

Caceres, Manuel; Ma, Yicheng; Rankin, J. Scott; Saha-Chaudhuri, Paramita; Englum, Brian R.; Gammie, James S.; Suri, Rakesh M.; Thourani, Vinod H.; Esmailian, Fardad; Czer, Lawrence S.; Puskas, John D.; Svensson, Lars G.

2014-01-01

OBJECTIVES Aortic root surgery is transitioning to aortic valve sparing (AVS), but little is known about the relative early outcomes of AVS versus composite graft-valve replacement (CVR). This study assessed mortality differences for AVS versus CVR to guide future practice decisions. METHODS From January 2000 to June 2011, 31 747 patients had aortic root replacement with AVS (n = 3585; 11%) or CVR (n = 28 162; 89%). The cohort of Overall patients was divided into two subgroups: high-risk patients (n = 20 356; 6% AVS) having age >75 years, endocarditis, aortic stenosis, dialysis, multiple valves, reoperation or emergency/salvage status, and the remaining low-risk patients (n = 11 388; 21% AVS). Using logistic regression analysis, outcomes were presented as unadjusted operative mortality (UOM), risk-adjusted operative mortality (AOM) and adjusted odds ratio (AOR) for mortality. RESULTS Baseline characteristics for the Overall group (AVS versus CVR) were: mean age (52 vs 57 years), endocarditis (1 vs 11%), aortic stenosis (4 vs 36%), dialysis (1 vs 2%), multiple valves (7 vs 10%), reoperation (6 vs 17%) and emergency status (14 vs 12%) (all P < 0.0001). In high- and low-risk groups, baseline differences narrowed, and lower mortality was generally observed with AVS: (AVS versus CVR) UOM group Overall (4.5 vs 8.9%)*, group High-risk (10.5 vs 11.7%), group Low-risk (1.4 vs 3.1%)*; AOM group Overall (6.2 vs 8.6%), group High-risk (10.1 vs 11.7%), group Low-risk (2.2 vs 2.8%); AOR group Overall (0.59)*, group High-risk (0.62)*, group Low-risk (0.69). *P < 0.05. CONCLUSIONS Relative risk-adjusted mortality seemed comparable with AVS versus CVR in low- and high-risk subgroups. These data support judicious expansion of aortic valve repair in patients having aortic root replacement. PMID:24639452

Discovery of siderite in marine sediment: Source and effect of violent gas venting at the Tsanyao Mud Volcano, offshore SW Taiwan

NASA Astrophysics Data System (ADS)

Tseng, Y.; Lin, S.; Hsieh, I. C.; Lien, K. L.

2016-12-01

Tsanyao mud volcano is a 400 meters high, 5 kilometers in diameter, a center crater of 50 meters width activing venting mud diapir. The gigantic size of mud volcano indicate massive transportation of material, i.e., gas, fluid, and breccia from deep to the sea floor in building up the mud volcano. The mud volcano is located at the upper slope of the accretionary wedge with a surrounding water depth of about xx m, offshore Southwestern Taiwan. On shore, a series of active mud volcanos also exist in a trend similar to those found offshore. In order to understand sources of gas, fluid, solid materials and the effect of gas migration and associate authigenic mineral formation, we have obtained multibeam bathymetry, water column echo sounding, together with sediment XRD and SEM and pore water composition of methane, sulfide, sulfate, chloride, potassium, lithium, boron, and water O-18 at the study mud volcano. We have observed more than 30 flares around the main cone within a perimeter of 10 square miles. δ13C values of methane in the pore water ranged from -30 to -50 ‰. The lower C13 ratios, together with high C2+/C1 ratios demonstrated that vent gas is mostly thermogenic in origin. Higher thermal gradient and water temperature indicated that cone top is unfavorable for gas-hydrate formation, however, gas hydrate may exist at a deeper part of the mud volcano system. High concentration of sulfide presence right near the sulfate-methane interface, a result of anoxic methane oxidation. However, low concentrations of pyrite in sediments indicated that AOM did not favor pyrite formation at depth. In addition, abundant siderite were found in the sediments collected in the mud volcano cone. Rapid consumption of sulfate through AOM reaction generated a condition favor the siderite fomation, instead of the typical pyrite formation commonly observed.

Mortality characteristics of aortic root surgery in North America.

PubMed

Caceres, Manuel; Ma, Yicheng; Rankin, J Scott; Saha-Chaudhuri, Paramita; Englum, Brian R; Gammie, James S; Suri, Rakesh M; Thourani, Vinod H; Esmailian, Fardad; Czer, Lawrence S; Puskas, John D; Svensson, Lars G

2014-11-01

Aortic root surgery is transitioning to aortic valve sparing (AVS), but little is known about the relative early outcomes of AVS versus composite graft-valve replacement (CVR). This study assessed mortality differences for AVS versus CVR to guide future practice decisions. From January 2000 to June 2011, 31 747 patients had aortic root replacement with AVS (n = 3585; 11%) or CVR (n = 28 162; 89%). The cohort of Overall patients was divided into two subgroups: high-risk patients (n = 20 356; 6% AVS) having age >75 years, endocarditis, aortic stenosis, dialysis, multiple valves, reoperation or emergency/salvage status, and the remaining low-risk patients (n = 11 388; 21% AVS). Using logistic regression analysis, outcomes were presented as unadjusted operative mortality (UOM), risk-adjusted operative mortality (AOM) and adjusted odds ratio (AOR) for mortality. Baseline characteristics for the Overall group (AVS versus CVR) were: mean age (52 vs 57 years), endocarditis (1 vs 11%), aortic stenosis (4 vs 36%), dialysis (1 vs 2%), multiple valves (7 vs 10%), reoperation (6 vs 17%) and emergency status (14 vs 12%) (all P < 0.0001). In high- and low-risk groups, baseline differences narrowed, and lower mortality was generally observed with AVS: (AVS versus CVR) UOM group Overall (4.5 vs 8.9%)*, group High-risk (10.5 vs 11.7%), group Low-risk (1.4 vs 3.1%)*; AOM group Overall (6.2 vs 8.6%), group High-risk (10.1 vs 11.7%), group Low-risk (2.2 vs 2.8%); AOR group Overall (0.59)*, group High-risk (0.62)*, group Low-risk (0.69). *P < 0.05. Relative risk-adjusted mortality seemed comparable with AVS versus CVR in low- and high-risk subgroups. These data support judicious expansion of aortic valve repair in patients having aortic root replacement. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Examination of the physical properties of Microcystis aeruginosa flocs produced on coagulation with metal salts.

PubMed

Gonzalez-Torres, A; Putnam, J; Jefferson, B; Stuetz, R M; Henderson, R K

2014-09-01

Coagulation-flocculation (C-F) is a key barrier to cyanobacterial and algal cell infiltration in water treatment plants during seasonal blooms. However, the resultant cell floc properties, in terms of size, strength and density, which dominate under different coagulation conditions and govern cell removal, are not well understood. This paper investigated the floc properties produced during C-F of the cyanobacterium, Microcystis aeruginosa, under low and high doses of aluminium sulphate and ferric chloride coagulants and at different pH values, so as to promote charge neutralisation (CN) and sweep flocculation (SF) dominant conditions (or a combination of these). It was demonstrated that application of ferric chloride produced larger flocs that resulted in higher cell removal during jar testing. These flocs were also larger than those observed for natural organic matter (NOM) and kaolin, suggesting a role of algogenic organic matter (AOM) as an inherent bioflocculant. Under SF conditions, stronger flocs were produced; however, these had lower capacity for size recovery after exposure to high shear. Analysis of particle size distribution demonstrated that large scale fragmentation followed by erosion dominated for CN while erosion dominated under SF conditions. Overall, marked differences were observed dependent on the coagulation regime imposed that have implications for improving robustness of cell removal by downstream separation processes. While the cyanobacterium, M. aeruginosa, appeared to share general floc characteristics commonly observed for NOM and kaolin flocs, there were distinct differences in terms of size and strength, which may be attributed to AOM. Copyright © 2014 Elsevier Ltd. All rights reserved.

NC10 Bacteria in a Marine Oxygen Minimum Zone

NASA Astrophysics Data System (ADS)

Padilla, C. C.; Bristow, L. A.; Benson, C. R.; Sarode, N. D.; Girguis, P. R.; Glass, J. B.; DiChristina, T. J.; Thamdrup, B.; Stewart, F. J.

2014-12-01

Marine oxygen minimum zones (OMZs) are key regions of nitrogen cycling and nitrogen loss as N2. The potential for methane cycling to influence OMZ nitrogen budgets remains largely unknown. The anaerobic oxidation of methane (AOM) coupled to nitrite or nitrate reduction has been shown to be a potential source of methane consumption, N loss, and oxygen production in freshwater sediments, but has not been described for marine pelagic environments. Nitrite-dependent AOM is performed by bacteria of the candidate division NC10 through an intra-aerobic pathway involving the dismutation of nitric oxide to O2 and N2. We explored the potential that NC10-like bacteria are present and active in the anoxic, nitrite-rich OMZ of the Eastern Tropical North Pacific. Community transcriptome sequencing confirmed the expression of genes with top matches to the NC10 bacterium 'Candidatus Methylomirabilis oxyfera.' NC10-like transcripts increased in relative abundance with depth into the anoxic OMZ core and included genes of aerobic methanotrophy and denitrification, as well as high numbers of transcripts matching norZ nitric oxide reductase, hypothesized to play a role in the O2-yielding dismutation reaction. Phylogenetic analysis of OMZ particulate methane monooxygenase (pmoA) and 16S rRNA gene sequences recovered by PCR revealed multiple clades of NC10 phylotypes in the OMZ. Preliminary data from OMZ enrichments revealed methane-dependent nitrite consumption, but further characterization is required to identify the pathways and organisms mediating this process. These findings expand the known environmental range of NC10 and suggest the possibility of previously uncharacterized linkages between OMZ nitrogen and methane cycles.

Continuous wave operation of quantum cascade lasers with frequency-shifted feedback

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyakh, A., E-mail: arkadiy.lyakh@ucf.edu; NanoScience Technology Center, University of Central Florida, 12424 Research Pkwy, Orlando, FL 32826; College of Optics and Photonics, University of Central Florida, 304 Scorpius St, Orlando, FL 32826

2016-01-15

Operation of continuous wave quantum cascade lasers with a frequency-shifted feedback provided by an acousto-optic modulator is reported. Measured linewidth of 1.7 cm{sup −1} for these devices, under CW operating conditions, was in a good agreement with predictions of a model based on frequency-shifted feedback seeded by spontaneous emission. Linewidth broadening was observed for short sweep times, consistent with sound wave grating period variation across the illuminated area on the acousto-optic modulator. Standoff detection capability of the AOM-based QCL setup was demonstrated for several solid materials.

A quantitative assessment of methane cycling in Hikurangi Margin sediments (New Zealand) using geophysical imaging and biogeochemical modeling

NASA Astrophysics Data System (ADS)

Luo, Min; Dale, Andrew W.; Haffert, Laura; Haeckel, Matthias; Koch, Stephanie; Crutchley, Gareth; De Stigter, Henko; Chen, Duofu; Greinert, Jens

2016-12-01

Takahe seep, located on the Opouawe Bank, Hikurangi Margin, is characterized by a well-defined subsurface seismic chimney structure ˜80,500 m2 in area. Subseafloor geophysical data based on acoustic anomaly layers indicated the presence of gas hydrate and free gas layers within the chimney structure. Reaction-transport modeling was applied to porewater data from 11 gravity cores to constrain methane turnover rates and benthic methane fluxes in the upper 10 m. Model results show that methane dynamics were highly variable due to transport and dissolution of ascending gas. The dissolution of gas (up to 3761 mmol m-2 yr-1) dwarfed the rate of methanogenesis within the simulated sediment column (2.6 mmol m-2 yr-1). Dissolved methane is mainly consumed by anaerobic oxidation of methane (AOM) at the base of the sulfate reduction zone and trapped by methane hydrate formation below it, with maximum rates in the central part of the chimney (946 and 2420 mmol m-2 yr-1, respectively). A seep-wide methane budget was constrained by combining the biogeochemical model results with geophysical data and led to estimates of AOM rates, gas hydrate formation, and benthic dissolved methane fluxes of 3.68 × 104 mol yr-1, 73.85 × 104 mol yr-1, and 1.19 × 104 mol yr-1, respectively. A much larger flux of methane probably escapes in gaseous form through focused bubble vents. The approach of linking geochemical model results with spatial geophysical data put forward here can be applied elsewhere to improve benthic methane turnover rates from limited single spot measurements to larger spatial scales.

Cerumen: A fundamental but neglected problem by pediatricians.

PubMed

Marchisio, Paola; Pipolo, Carlotta; Landi, Massimo; Consonni, Dario; Mansi, Nicola; Di Mauro, Giuseppe; Salvatici, Elisabetta; Di Pietro, Pasquale; Esposito, Susanna; Felisati, Giovanni; Principi, Nicola

2016-08-01

Under physiological conditions, cerumen (Ce) is regularly extruded from the ear canal by a self-cleaning mechanism. Failure of this mechanism leads to excessive accumulation or impaction of Ce. Limited data are available concerning the prevalence of cerumen in healthy and sick infants and children. We assessed the prevalence of Ce in a large population of infants and children and compared the Ce removal attitudes of paediatricians (PEDs) and otorhinolaryngologists (ENTs). Children seen in November 2014 for acute respiratory infections, including suspected acute otitis media, or well-being visits, were enrolled. The following data were recorded: presence, laterality, and amount of Ce; presenting complaints and final diagnosis; attempt to remove Ce during the visit; and type of physician. Among 819 children aged 1 month to 12 years, Ce was present in 594 (72.5%), of whom 478 (80.5%) had bilateral Ce, and 261 (43.9%) had Ce in a relevant amount (cerumen obstructing at least 50% of the ear canal). Presence of Ce was more common in younger and in African or Asian children. PEDs were less likely to remove cerumen than ENTs (28.8% vs 91.0%, p < 0.001) irrespective of age, gender, race and reason for visit. Ce was removed by PEDs in less than one-third of sick children with a final diagnosis of acute otitis media (AOM) (31.6%) compared with almost all the children by ENTs (95.6%, p < 0.001). Ce is highly prevalent in healthy and sick children but is quite neglected by PEDs. Educational programs to reinforce the importance of Ce removal and to improve the techniques for removal in case of suspected AOM should be implemented and rigorously evaluated in order to avoid incorrect diagnosis and erroneous treatments. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An 11,000-year record of depositional environmental change based upon particulate organic matter and stable isotopes (C and N) in a lake sediment in southeastern Brazil

NASA Astrophysics Data System (ADS)

Lorente, Flávio Lima; Pessenda, Luiz Carlos Ruiz; Oboh-Ikuenobe, Francisca; Buso Junior, Antonio Alvaro; Rossetti, Dilce de Fátima; Giannini, Paulo César Fonseca; Cohen, Marcelo Cancela Lisboa; de Oliveira, Paulo Eduardo; Mayle, Francis Edward; Francisquini, Mariah Izar; França, Marlon Carlos; Bendassolli, José Albertino; Macario, Kita

2018-07-01

The aim of this paper is to reconstruct an 11,000-year history of depositional environmental change in southeastern Brazil, based upon the integration of particulate organic matter and stable isotope (C and N) data from a 136-cm sediment core from Lake Canto Grande. These proxies are used to explore the evolution of terrestrial and marine influence on the lake. Isotopic (δ13C: -27.87‰ to -31.9‰; δ15N: -0.07‰-4.9‰) and elemental (total organic carbon - TOC: 0.58%-37.19%; total nitrogen - TN: 0.08%-1.73%; C/N: 0.3 to 54.7) values recorded in Lake Canto Grande suggest that the sedimentary organic matter was derived from mostly C3 land plants and freshwater phytoplankton. Particulate organic matter and cluster analyses distinguished four associations characterized by the predominance of amorphous organic matter, followed by phytoclasts and palynomorphs. These results indicate two different phases of lake evolution. The first phase (136 - 65 cm; ∼10,943 cal yr. B.P. to ∼8529 cal yr. B.P.) is recorded by sand layers interbedded with mud, which contain amorphous organic matter (AOM, 45-59%) and phytoclasts (opaques - OP: 6-18%; non-opaques - NOP: 17-23%) which indicate a floodplain area. The second phase (65-0 cm; ∼8529 cal yr. B.P. to ∼662 cal yr. B.P.) comprises mud, AOM (68-86%) and palynomorphs (PAL, 8-16%) related to lake establishment comparable to modern conditions. Thus, characterizing particulate organic matter, in combination with stable isotopes, proved to be invaluable proxies for lacustrine paleoenvironmental change through the Holocene.

High-fat diets rich in saturated fat protect against azoxymethane/dextran sulfate sodium-induced colon cancer.

PubMed

Enos, Reilly T; Velázquez, Kandy T; McClellan, Jamie L; Cranford, Taryn L; Nagarkatti, Mitzi; Nagarkatti, Prakash S; Davis, J Mark; Murphy, E Angela

2016-06-01

High-fat-diet (HFD) consumption is associated with colon cancer risk. However, little is known about how the lipid composition of a HFD can influence prooncogenic processes. We examined the effects of three HFDs differing in the percentage of total calories from saturated fat (SF) (6, 12, and 24% of total caloric intake), but identical in total fat (40%), and a commercially available Western diet (26 and 41% saturated and total fat, respectively) on colon cancer development using the azoxymethane (AOM)/dextran sulfate sodium (DSS) murine model. A second dose-response experiment was performed using diets supplemented with the saturated-fatty-acid (SFA)-rich coconut oil. In experiment 1, we found an inverse association between SF content and tumor burden. Furthermore, increased SF content was associated with reduced inflammation, increased apoptosis, and decreased proliferation. The second dose-response experiment was performed to test whether this effect may be attributed to the SF content of the diets. Consistent with the initial experiment, we found that high SF content was protective, at least in male mice; there was a decrease in mortality in mice consuming the highest concentration of SFAs. To explore a potential mechanism for these findings, we examined colonic mucin 2 (Muc2) protein content and found that the HFDs with the highest SF content had the greatest concentration of Muc2. Our data suggest that high dietary SF is protective in the AOM/DSS model of colon cancer, which may be due, at least in part, to the ability of SF to maintain intestinal barrier integrity through increased colonic Muc2. Copyright © 2016 the American Physiological Society.

Dietary folate does not significantly affect the intestinal microbiome, inflammation or tumorigenesis in azoxymethane-dextran sodium sulphate-treated mice.

PubMed

MacFarlane, Amanda J; Behan, Nathalie A; Matias, Fernando M G; Green, Judy; Caldwell, Don; Brooks, Stephen P J

2013-02-28

Inflammatory bowel disease (IBD) is a risk factor for the development of colon cancer. Environmental factors including diet and the microflora influence disease outcome. Folate and homocysteine have been associated with IBD-mediated colon cancer but their roles remain unclear. We used a model of chemically induced ulcerative colitis (dextran sodium sulphate (DSS)) with or without the colon carcinogen azoxymethane (AOM) to determine the impact of dietary folic acid (FA) on colonic microflora and the development of colon tumours. Male mice (n 15 per group) were fed a FA-deficient (0 mg/kg), control (2 mg/kg) or FA-supplemented (8 mg/kg) diet for 12 weeks. Folate status was dependent on the diet (P< 0·001) and colitis-induced treatment (P= 0·04) such that mice with colitis had lower circulating folate. FA had a minimal effect on tumour initiation, growth and progression, although FA-containing diets tended to be associated with a higher tumour prevalence in DSS-treated mice (7-20 v. 0%, P= 0·08) and the development of more tumours in the distal colon of AOM-treated mice (13-83% increase, P= 0·09). Folate deficiency was associated with hyperhomocysteinaemia (P< 0·001) but homocysteine negatively correlated with tumour number (r - 0·58, P= 0·02) and load (r - 0·57, P= 0·02). FA had no effect on the intestinal microflora. The present data indicate that FA intake has no or little effect on IBD or IBD-mediated colon cancer in this model and that hyperhomocysteinaemia is a biomarker of dietary status and malabsorption rather than a cause of IBD-mediated colon cancer.

Towards Biogeochemical Modeling of Anaerobic Oxidation of Methane: Characterization of Microbial Communities in Methane-bearing North American Continental Margin Sediments

NASA Astrophysics Data System (ADS)

Graw, M. F.; Solomon, E. A.; Chrisler, W.; Krause, S.; Treude, T.; Ruppel, C. D.; Pohlman, J.; Colwell, F. S.

2015-12-01

Methane advecting through continental margin sediments may enter the water column and potentially contribute to ocean acidification and increase atmospheric methane concentrations. Anaerobic oxidation of methane (AOM), mediated by syntrophic consortia of anaerobic methanotrophic archaea and sulfate-reducing bacteria (ANME-SRB), consumes nearly all dissolved methane in methane-bearing sediments before it reaches the sediment-water interface. Despite the significant role ANME-SRB play in carbon cycling, our knowledge of these organisms and their surrounding microbial communities is limited. Our objective is to develop a metabolic model of ANME-SRB within methane-bearing sediments and to couple this to a geochemical reaction-transport model for these margins. As a first step towards this goal, we undertook fluorescent microscopic imaging, 16S rRNA gene deep-sequencing, and shotgun metagenomic sequencing of sediments from the US Pacific (Washington) and northern Atlantic margins where ANME-SRB are present. A successful Illumina MiSeq sequencing run yielded 106,257 bacterial and 857,834 archaeal 16S rRNA gene sequences from 12 communities from the Washington Margin using both universal prokaryotic and archaeal-specific primer sets. Fluorescent microscopy confirmed the presence of cells of the ANME-2c lineage in the sequenced communities. Microbial community characterization was coupled with measurements of sediment physical and geochemical properties and, for samples from the US Atlantic margin, 14C-based measurements of AOM rates and 35S-based measurements of sulfate reduction rates. These findings have the potential to increase understanding of ANME-SRB, their surrounding microbial communities, and their role in carbon cycling within continental margins. In addition, they pave the way for future efforts at developing a metabolic model of ANME-SRB and coupling it to geochemical models of the US Washington and Atlantic margins.

Chemopreventive activity of GEN-27, a genistein derivative, in colitis-associated cancer is mediated by p65-CDX2-β-catenin axis

PubMed Central

Wang, Hong; Fan, Huimin; Li, Yan; Wang, Jianing; Zhang, Xu; Lu, Jinrong; Ji, Hui; Hu, Rong

2016-01-01

Nonresolving inflammation in the intestine predisposes individuals to colitis-associated colorectal cancer (CAC), which leads to high morbidity and mortality. Here we show that genistein-27 (GEN-27), a derivative of genistein, inhibited proliferation of human colorectal cancer cells through inhibiting β-catenin activity. Our results showed that GEN-27 increased expressions of adenomatous polyposis coli (APC) and axis inhibition protein 2 (AXIN2), and reduced β-catenin nuclear localization, which resulted from the inhibition of NF-κB/p65 nuclear localization and up-regulation of caudal-related homeobox transcription factor 2 (CDX2). Furthermore, GEN-27 decreased binding of p65 to the silencer region of CDX2 and increased binding of CDX2 to the promoter regions of APC and AXIN2, thus inhibiting the activation of β-catenin induced by TNF-α. Importantly, GEN-27 protected mice from azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colon carcinogenesis, with reduced mortality, tumor number and tumor volume. Histopathology, immunohistochemistry and flow cytometry revealed that dietary GEN-27 significantly decreased secretion of proinflammatory cytokines and macrophage infiltration. Moreover, GEN-27 inhibited AOM/DSS-induced p65 and β-catenin nuclear translocation, while promoted the expression of CDX2, APC, and AXIN2. Taken together, our findings demonstrate that the anti-proliferation effect of GEN-27 in vitro and the prevention of CAC in vivo is mediated by p65-CDX2-β-catenin axis via inhibiting β-catenin target genes. Our results imply that GEN-27 could be a promising candidate for the chemoprevention of CAC. PMID:26910375

Feeding of soy protein isolate to rats during pregnancy and lactation suppresses formation of aberrant crypt foci in their progeny's colons: interaction of diet with fetal alcohol exposure

PubMed Central

Linz, Amanda L; Xiao, Rijin; Parker, James G; Simpson, Pippa M; Badger, Thomas M; Simmen, Frank A

2004-01-01

Soy protein isolate (SPI) in the diet may inhibit colon tumorigenesis. We examined azoxymethane (AOM)-induced aberrant crypt foci (ACF) in male rats in relation to lifetime, pre-weaning, or post-weaning dietary exposure to SPI and also within the context of fetal alcohol exposure. Pregnant Sprague Dawley rats were fed AIN-93G diets containing casein (20%, the control diet) or SPI (20%) as the sole protein source starting on gestation day 4 (GD 4). Progeny were weaned on postnatal day (PND) 21 to the same diet as their dams and were fed this diet until termination of the experiment at PND 138. Rats received AOM on PND 89 and 96. Lifetime (GD 4 to PND 138) feeding of SPI led to reduced frequency of ACF with 4 or more crypts in the distal colon. Progeny of dams fed SPI only during pregnancy and lactation or progeny fed SPI only after weaning exhibited similarly reduced frequency of large ACF in distal colon. Number of epithelial cells, in the distal colon, undergoing apoptosis was unaffected by diet. SPI reduced weight gain and adiposity, but these were not correlated with fewer numbers of large ACF. Lifetime SPI exposure similarly inhibited development of large ACF in Sprague Dawley rats whose dams were exposed to ethanol during pregnancy. In summary, feeding of SPI to rat dams during pregnancy and lactation suppresses numbers of large ACF in their progeny, implying a long-term or permanent change elicited by the maternal diet. Moreover, results support the use of ACF as an intermediate endpoint for elucidating effects of SPI and its biochemical constituents in colon cancer prevention in rats. PMID:15488141

Hospital discharges for fever and neutropenia in pediatric cancer patients: United States, 2009.

PubMed

Mueller, Emily L; Walkovich, Kelly J; Mody, Rajen; Gebremariam, Achamyeleh; Davis, Matthew M

2015-05-10

Fever and neutropenia (FN) is a common complication of pediatric cancer treatment, but hospital utilization patterns for this condition are not well described. Data were analyzed from the Kids' Inpatient Database (KID), an all-payer US hospital database, for 2009. Pediatric FN patients were identified using: age ≤19 years, urgent or emergent admit type, non-transferred, and a combination of ICD-9-CM codes for fever and neutropenia. Sampling weights were used to permit national inferences. Pediatric cancer patients accounted for 1.5 % of pediatric hospital discharges in 2009 (n = 110,967), with 10.1 % of cancer-related discharges meeting FN criteria (n = 11,261). Two-fifths of FN discharges had a "short length of stay" (SLOS) of ≤3 days, which accounted for approximately $65.5 million in hospital charges. Upper respiratory infection (6.0 %) and acute otitis media (AOM) (3.7 %) were the most common infections associated with SLOS. Factors significantly associated with SLOS included living in the Midwest region (OR = 1.65, 1.22-2.24) or West region (OR 1.54, 1.11-2.14) versus Northeast, having a diagnosis of AOM (OR = 1.39, 1.03-1.87) or viral infection (OR = 1.63, 1.18-2.25) versus those without those comorbidities, and having a soft tissue sarcoma (OR = 1.47, 1.05-2.04), Hodgkin lymphoma (OR = 2.33, 1.62-3.35), or an ovarian/testicular tumor (OR = 1.76, 1.05-2.95) compared with patients without these diagnoses. FN represents a common precipitant for hospitalizations among pediatric cancer patients. SLOS admissions are rarely associated with serious infections, but contribute substantially to the burden of hospitalization for pediatric FN.

Ab Initio Ligand Field Molecular Mechanics and the Nature of Metal-Ligand π-Bonding in Fe(II) 2,6-di(pyrazol-1-yl)pyridine Spin Crossover Complexes.

PubMed

Deeth, Robert J; Halcrow, Malcolm A; Kershaw Cook, Laurence J; Raithby, Paul R

2018-04-06

A ligand field molecular mechanics (LFMM) force field has been constructed for the spin states of [Fe(bpp) 2 ] 2+ (bpp=2,6-di(pyrazol-1-yl)pyridine) and related complexes. A new charge scheme is employed which interpolates between partial charges for neutral bpp and protonated [H 3 bpp] 3+ to achieve a target metal charge. The LFMM angular overlap model (AOM) parameters are fitted to fully ab initio d orbital energies. However, several AOM parameter sets are possible. The ambiguity is resolved by calculating the Jahn-Teller distortion mode for high spin, which indicates that in [Fe(bpp) 2 ] 2+ pyridine is a π-acceptor and pyrazole a weak π-donor. The alternative fit, assumed previously, where both ligands act as π-donors leads to an inconsistent distortion. LFMM optimisations in the presence of [BF 4 ] - or [PF 6 ] - anions are in good agreement with experiment and the model also correctly predicts the spin state energetics for 3-pyrazolyl substituents where the interactions are mainly steric. However, for 4-pyridyl or 4-pyrazolyl substituents, LFMM only treats the electrostatic contribution which, for the pyridyl substituents, generates a fair correlation with the spin crossover transition temperatures, T 1/2 , but in the reverse sense to the dominant electronic effect. Thus, LFMM generates its smallest spin state energy difference for the substituent with the highest T 1/2 . One parameter set for all substituted bpp ligands is insufficient and further LFMM development will be required. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Berberine regulates AMP-activated protein kinase signaling pathways and inhibits colon tumorigenesis in mice

PubMed Central

Li, Weidong; Hua, Baojin; Saud, Shakir M.; Lin, Hongsheng; Hou, Wei; Matter, Matthias S.; Jia, Libin; Colburn, Nancy H.; Young, Matthew R.

2015-01-01

Colorectal cancer, a leading cause of cancer death, has been linked to inflammation and obesity. Berberine, an isoquinoline alkaloid, possesses anti-inflammatory, anti-diabetes and anti-tumor properties. In the azoxymethane initiated and dextran sulfate sodium (AOM/DSS) promoted colorectal carcinogenesis mouse model, berberine treated mice showed a 60% reduction in tumor number (P=0.009), a 48% reduction in tumors <2 mm, (P=0.05); 94% reduction in tumors 2-4 mm, (P=0.001) and 100% reduction in tumors >4 mm (P=0.02) compared to vehicle treated mice. Berberine also decreased AOM/DSS induced Ki-67 and COX-2 expression. In vitro analysis showed that in addition to its anti-proliferation activity, berberine also induced apoptosis in colorectal cancer cell lines. Berberine activated AMP-activated protein kinase (AMPK), a major regulator of metabolic pathways, and inhibited mammalian target of rapamycin (mTOR), a downstream target of AMPK. Furthermore, 4E-binding protein-1 and p70 ribosomal S6 kinases, downstream targets of mTOR, were down regulated by berberine treatment. Berberine did not affect Liver kinase B1 (LKB1) activity or the mitogen-activated protein kinase pathway. Berberine inhibited Nuclear Factor kappa-B (NF-κB) activity, reduced the expression of cyclin D1 and survivin, induced phosphorylation of p53 and increased caspase-3 cleavage in vitro. Berberine inhibition of mTOR activity and p53 phosphorylation was found to be AMPK dependent, while inhibition NF-κB was AMPK independent. In vivo, berberine also activated AMPK, inhibited mTOR and p65 phosphorylation and activated caspase-3 cleavage. Our data suggests that berberine suppresses colon epithelial proliferation and tumorigenesis via AMPK dependent inhibition of mTOR activity and AMPK independent inhibition of NF-κB. PMID:24838344

Inhibition of colon carcinogenesis by a standardized Cannabis sativa extract with high content of cannabidiol.

PubMed

Romano, Barbara; Borrelli, Francesca; Pagano, Ester; Cascio, Maria Grazia; Pertwee, Roger G; Izzo, Angelo A

2014-04-15

Colon cancer is a major public health problem. Cannabis-based medicines are useful adjunctive treatments in cancer patients. Here, we have investigated the effect of a standardized Cannabis sativa extract with high content of cannabidiol (CBD), here named CBD BDS, i.e. CBD botanical drug substance, on colorectal cancer cell proliferation and in experimental models of colon cancer in vivo. Proliferation was evaluated in colorectal carcinoma (DLD-1 and HCT116) as well as in healthy colonic cells using the MTT assay. CBD BDS binding was evaluated by its ability to displace [(3)H]CP55940 from human cannabinoid CB1 and CB2 receptors. In vivo, the effect of CBD BDS was examined on the preneoplastic lesions (aberrant crypt foci), polyps and tumours induced by the carcinogenic agent azoxymethane (AOM) as well as in a xenograft model of colon cancer in mice. CBD BDS and CBD reduced cell proliferation in tumoral, but not in healthy, cells. The effect of CBD BDS was counteracted by selective CB1 and CB2 receptor antagonists. Pure CBD reduced cell proliferation in a CB1-sensitive antagonist manner only. In binding assays, CBD BDS showed greater affinity than pure CBD for both CB1 and CB2 receptors, with pure CBD having very little affinity. In vivo, CBD BDS reduced AOM-induced preneoplastic lesions and polyps as well as tumour growth in the xenograft model of colon cancer. CBD BDS attenuates colon carcinogenesis and inhibits colorectal cancer cell proliferation via CB1 and CB2 receptor activation. The results may have some clinical relevance for the use of Cannabis-based medicines in cancer patients. Copyright © 2013 Elsevier GmbH. All rights reserved.

In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

PubMed

Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

2015-11-01

We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis. ©2015 American Association for Cancer Research.

Polyethylene Glycol Mediated Colorectal Cancer Chemoprevention: Roles of Epidermal Growth Factor Receptor and Snail

PubMed Central

Wali, Ramesh K.; Kunte, Dhananjay P.; Koetsier, Jennifer L.; Bissonnette, Marc; Roy, Hemant K.

2008-01-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We previously reported that Snail/β-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overepressed in ~80% of human colorectal cancers (CRC), on PEG-mediated anti-proliferative and hence anti-neoplastic effects in azoxymethane (AOM)-rats and HT-29 colon cancer cells. AOM-rats were randomized to either standard diet or one with 10% PEG 3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (p<0.001). Similar PEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pre-treating cells with gefitinib or stably transfecting with EGFR-shRNA and measured the effect of PEG on proliferation. In either case PEG effect was blunted suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-shRNA cells, besides having reduced membrane EGFR also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/β-catenin pathway playing the central intermediary function. PMID:18790788

Polyethylene glycol-mediated colorectal cancer chemoprevention: roles of epidermal growth factor receptor and Snail.

PubMed

Wali, Ramesh K; Kunte, Dhananjay P; Koetsier, Jennifer L; Bissonnette, Marc; Roy, Hemant K

2008-09-01

Polyethylene glycol (PEG) is a clinically widely used agent with profound chemopreventive properties in experimental colon carcinogenesis. We reported previously that Snail/beta-catenin signaling may mediate the suppression of epithelial proliferation by PEG, although the upstream events remain unclear. We report herein the role of epidermal growth factor receptor (EGFR), a known mediator of Snail and overexpressed in approximately 80% of human colorectal cancers, on PEG-mediated antiproliferative and hence antineoplastic effects in azoxymethane (AOM) rats and HT-29 colon cancer cells. AOM rats were randomized to either standard diet or one with 10% PEG-3350 and euthanized 8 weeks later. The colonic samples were subjected to immunohistochemical or Western blot analyses. PEG decreased mucosal EGFR by 60% (P < 0.001). Similar PEG effects were obtained in HT-29 cells. PEG suppressed EGFR protein via lysosmal degradation with no change in mRNA levels. To show that EGFR antagonism per se was responsible for the antiproliferative effect, we inhibited EGFR by either pretreating cells with gefitinib or stably transfecting with EGFR-short hairpin RNA and measured the effect of PEG on proliferation. In either case, PEG effect was blunted, suggesting a vital role of EGFR. Flow cytometric analysis revealed that EGFR-short hairpin RNA cells, besides having reduced membrane EGFR, also expressed low Snail levels (40%), corroborating a strong association. Furthermore, in EGFR silenced cells, PEG effect on EGFR or Snail was muted, similar to that on proliferation. In conclusion, we show that EGFR is the proximate membrane signaling molecule through which PEG initiates antiproliferative activity with Snail/beta-catenin pathway playing the central intermediary function.

Extending single molecule fluorescence observation time by amplitude-modulated excitation

PubMed Central

Kisley, Lydia; Chang, Wei-Shun; Cooper, David; Mansur, Andrea P; Landes, Christy F

2014-01-01

We present a hardware-based method that can improve single molecule fluorophore observation time by up to 1500% and super-localization by 47% for the experimental conditions used. The excitation was modulated using an acousto-optic modulator (AOM) synchronized to the data acquisition and inherent data conversion time of the detector. The observation time and precision in super-localization of four commonly used fluorophores were compared under modulated and traditional continuous excitation, including direct total internal reflectance excitation of Alexa 555 and Cy3, non-radiative Förster resonance energy transfer (FRET) excited Cy5, and direct epi-fluorescence wide field excitation of Rhodamine 6G. The proposed amplitude-modulated excitation does not perturb the chemical makeup of the system or sacrifice signal and is compatible with multiple types of fluorophores. Amplitude-modulated excitation has practical applications for any fluorescent study utilizing an instrumental setup with time-delayed detectors. PMID:24587894

BIOCHEMICAL COMPOSITION AND NUTRITIONAL EVALUATION OF BARLEY RIHANE (HORDEUM VULGARE L.).

PubMed

Lahouar, Lamia; Ghrairi, Fatma; El Arem, Amira; Medimagh, Sana; El Felah, Mouledi; Salem, Hichem Ben; Achour, Lotfi

2017-01-01

Many experimental studies have suggested an important role for barley Rihane(BR)in the prevention of colon cancer and cardiovascular diseases. The objective of this study was to evaluate the physico-chemical properties and nutritional characterizations of BR compared to other varieties grown in Tunisia (Manel, Roho and Tej). Total, insoluble and soluble dietary fiber(β-glucan), total protein, ash and some minerals of BR and Tunisian barley varieties were determined. The results revealed that BR is good source of dietary fiber mainly β-glucan compared to the other varieties. This variety is a relatively rich source of phosphorous and potassium and it contains many important unsaturated fatty acids. BR has higher nutritional value than other varieties. Barley Rihane has significant nutritional characterizations compared to others Tunisian barleys varieties. Abbreviations: BR, Barley Rihane; LDL, low density lipoprotein; HDL, high density lipoprotein; AOM, azoxymethane; TBV, Tunisian barley varieties; TGW, thousand grain weight; SW, weight specific; TDF, total dietary fiber; IDF, insoluble dietary fiber; SDF, soluble dietary fiber; DM, Dry Matter.

Reconstructing Methane Emission Events in the Arctic Ocean: Observations from the Past to Present

NASA Astrophysics Data System (ADS)

Panieri, G.; Mienert, J.; Fornari, D. J.; Torres, M. E.; Lepland, A.

2015-12-01

Methane hydrates are ice-like crystals that are present along continental margins, occurring in the pore space of deep sediments or as massive blocks near the seafloor. They form in high pressure and low temperature environments constrained by thermodynamic stability, and supply of methane. In the Arctic, gas hydrates are abundant, and the methane released by their destabilization can affect local to global carbon budgets and cycles, ocean acidification, and benthic community survival. With the aim to locate in space and time the periodicity of methane venting, CAGE is engaged in a vast research program in the Arctic, a component of which comprises the analyses of numerous sediment cores and correlative geophysical and geochemical data from different areas. Here we present results from combined analyses of biogenic carbonate archives along the western Svalbard Margin, which reveal past methane venting events in this region. The reconstruction of paleo-methane discharge is complicated by precipitation of secondary carbonate on foraminifera shells, driven by an increase in alkalinity during anaerobic oxidation of methane (AOM). The biogeochemical processes involved in methane cycling and processes that drive methane migration affect the depth where AOM occurs, with relevance to secondary carbonate formation. Our results show the value and complexity of separating primary vs. secondary signals in bioarchives with relevance to understanding fluid-burial history in methane seep provinces. Results from our core analyses are integrated with observations made during the CAGE15-2 cruise in May 2015, when we deployed a towed vehicle equipped with camera, multicore and water sampling capabilities. The instrument design was based on the Woods Hole Oceanographic Institution (WHOI) MISO TowCam sled equipped with a deep-sea digital camera and CTD real-time system. Sediment sampling was visually-guided using this system. In one of the pockmarks along the Vestnesa Ridge where high methane discharge was measured, we deployed the CAGE 888 marker as our first step in conducting time series studies to establish temporal variability going forward. This research is partially supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223259.

In vivo endoscopic Doppler optical coherence tomography imaging of the colon

PubMed Central

Welge, Weston A.; Barton, Jennifer K.

2017-01-01

Background and Objective Colorectal cancer remains the second deadliest cancer in the United States. Several screening methods exist, however detection of small polyps remains a challenge. Optical coherence tomography has been demonstrated to be capable of detecting lesions as small as 1 mm in the mouse colon, but detection is based on measuring a doubling of the mucosa thickness. The colon microvasculature may be an attractive biomarker of early tumor development because tumor vessels are characterized by irregular structure and dysfunction. Our goal was to develop an endoscopic method of detecting and segmenting colon vessels using Doppler optical coherence tomography to enable future studies for improving early detection and development of novel chemopreventive agents. Method We conducted in vivo colon imaging in an azoxymethane (AOM)-treated mouse model of colorectal cancer using a miniature endoscope and a swept-source OCT system at 1040 nm with a 16 kHz sweep rate. We applied the Kasai autocorrelation algorithm to laterally oversampled OCT B-scans to resolve vascular flow in the mucosa and submucosa. Vessels were segmented by applying a series of image processing steps: (1) intensity thresholding, (2) two-dimensional matched filtering, and (3) histogram segmentation. Results We observed differences in the vessels sizes and spatial distribution in a mature adenoma compared to surrounding undiseased tissue and compared the results with histology. We also imaged flow in four young mice (2 AOM-treated and 2 control) showing no significant differences, which is expected so early after carcinogen exposure. We also present flow images of adenoma in a living mouse and a euthanized mouse to demonstrate that no flow is detected after euthanasia. Conclusion We present, to the best of our knowledge, the first Doppler OCT images of in vivo mouse colon collected with a fiber-based endoscope. We also describe a fast and robust image processing method for segmenting vessels in the colon. These results suggest that Doppler OCT is a promising imaging modality for vascular imaging in the colon that requires no exogenous contrast agents. PMID:27546786

Stable carbon, nitrogen and sulfur isotopes in non-carbonate fractions of cold-seep carbonates

NASA Astrophysics Data System (ADS)

Feng, Dong; Peng, Yongbo; Peckmann, Jörn; Roberts, Harry; Chen, Duofu

2017-04-01

Sulfate-driven anaerobic oxidation of methane (AOM) supports chemosynthesis-based communities and limits the release of methane from marine sediments. This process promotes the formation of carbonates close to the seafloor along continental margins. The geochemical characteristics of the carbonate minerals of these rocks are increasingly understood, questions remain about the geochemical characteristics of the non-carbonate fractions. Here, we report stable carbon, nitrogen and sulfur isotope patterns in non-carbonate fractions of seep carbonates. The authigenic carbonates were collected from three modern seep provinces (Black Sea, Gulf of Mexico, and South China Sea) and three ancient seep deposits (Marmorito, northern Italy, Miocene; SR4 deposit of the Lincoln Creek Formation and Whiskey Creek, western Washington, USA, Eocene to Oligocene). The δ13C values of non-carbonate fractions range from ˜-25‰ to -80‰ VPDB. These values indicate that fossil methane mixed with varying amounts of pelagic organic matter is the dominant source of carbon in these fractions. The relatively small offset between the δ34S signatures of the non-carbonate fractions and the respective sulfide minerals suggests that locally produced hydrogen sulfide is the main source of sulfur in seep environments. The δ15N values of the non-carbonate fractions are generally lower than the corresponding values of deep-sea sediments, suggesting that organic nitrogen is mostly of a local origin. This study reveals the potential of using δ13C, δ15N, δ34S values to discern seep and non-seep deposits. In cases where δ13Ccarbonate values are only moderately low due to mixing processes and lipid biomarkers have been erased in the course of burial, it is difficult to trace back AOM owing to the lack of other records. This problem is even more pronounced when authigenic carbonate is not available in ancient seep environments. Acknowledgments: The authors thank BOEM and NOAA for their years' support of the deep-sea dives. Funding was provided by the NSF of China (Grants: 41422602 and 41373085) and the "Hundred Talents Program" of CAS.

Authigenic minerals related to carbon and sulfur biogeochemical cycling from deep-sea active methane seeps offshore South-West Africa

NASA Astrophysics Data System (ADS)

Pierre, C.; Blanc-Valleron, M.; Demange, J.; Boudouma, O.; Pape, T.; Himmler, T.; Fekete, N.; Spiess, V.

2011-12-01

The South-West African continental margin is well known for occurrences of active methane-rich fluid seeps that are associated with seafloor pockmarks in a broad range of water depths, from the shelf to the deep basins. High gas flares in the water column, luxurious oases of benthic fauna, gas hydrate accumulations and diagenetic carbonate crusts have been observed at these seeps. During the M76/3a expedition of R/V METEOR (summer 2008) gravity cores recovered abundant authigenic carbonate concretions from five pockmarks of the South-West African margin including previously studied sites (Hydrate Hole, Worm Hole, Regab Pockmark) and two sites (Deep Hole, Baboon Cluster) newly discovered during the cruise. Carbonate concretions were mostly associated to sediments settled by seep-associated benthic macrofauna and bearing shallow gas hydrates. We present new results of the comprehensive analysis of the mineralogy and isotope geochemistry of the diagenetic carbonates sampled in the five pockmarks. The mineralogy of authigenic carbonates is dominated by magnesian calcite and aragonite, associated occasionally with dolomite. The oxygen and carbon isotopic compositions of authigenic carbonates (+2.4 < δ18O % V-PDB < +6.2 ; -61.0 < δ13C % V-PDB < -40.1) indicate that microbial anaerobic oxidation of methane (AOM) was the main process controling carbonate precipitation within sub-seafloor sediments deposited from the glacial-time up to the present. The frequent occurrence of diagenetic gypsum crystals within the sediments demonstrates that bio-irrigation with oxygenated bottom water by the burrowing activity of benthic fauna caused the secondary oxidation of reduced sulfur (hydrogen sulfide and pyrite) that was produced by sulfate reducting bacteria as a by-product of AOM; during the sulfide oxidation process, the released acidity induced the partial dissolution of carbonates. Our results demonstrate also the strong link that existed between the carbon and sulfur cycles in cold seep systems where the anoxic-oxic boundary may move within the sediment due to variations in the strength of the methane flux.

Biogeochemical processes controlling authigenic carbonate formation within the sediment column from the Okinawa Trough

NASA Astrophysics Data System (ADS)

Li, Jiwei; Peng, Xiaotong; Bai, Shijie; Chen, Zhiyan; Van Nostrand, Joy D.

2018-02-01

Authigenic carbonates are one type of conspicuous manifestation in seep environments that can provide long-term archives of past seepage activity and methane cycling in the oceans. Comprehensive investigations of the microbial community functional structure and their roles in the process of carbonate formation are, however, lacking. In this study, the mineralogical, geochemical, and microbial functional composition were examined in seep carbonate deposits collected from the west slope of the northern section of the Okinawa Trough (OT). The aim of this work was to explore the correspondence between the mineralogical phases and microbial metabolism during carbonate deposit formation. The mineralogical analyses indicated that authigenic carbonate minerals (aragonite, magnesium-rich calcite, dolomite, ankerite and siderite) and iron-bearing minerals (limonite, chlorite, and biotite) were present in these carbonate samples. The carbon and oxygen isotopic values of the carbonate samples varied between -51.1‰ to -4.7‰ and -4.8‰ to 3.7‰, respectively. A negative linear correlation between carbon and oxygen isotopic compositions was found, indicating a mixture of methane-derived diagenetic (low δ13C/high 18O) carbonates and detrital origin (high δ13C/low 18O) carbonates at the OT. GeoChip analyses suggested that various metabolic activities of microorganisms, including methanogenesis, methane oxidation, sulfite oxidation, sulfate reduction, and metal biotransformations, all occurred during the formation process. On the basis of these findings, the following model for the methane cycle and seep carbonate deposit formation in the sediment column at the OT is proposed: (1) in the upper oxidizing zone, aerobic methane oxidation was the main way of methane consumption; (2) in the sulfate methane transition zone, sulfate-dependent AOM (anaerobic oxidation of methane) consumes methane, and authigenic minerals such as aragonite, magnesium-calcite, and sulfide minerals precipitate; (3) in the underlying sulfate depleted zone, the presence of iron-oxides supplied by hydrothermal fluids and terrestrial inputs created thermodynamically favorable conditions for Fe-dependent AOM to consume methane, and dolomite and siderite/ankerite precipitate in this zone.

Fe-C-S systematics in Bengal Fan sediments

NASA Astrophysics Data System (ADS)

Volvoikar, S. P.; Mazumdar, A.; Goswami, H.; Pujari, S.; Peketi, A.

2017-12-01

Global biogeochemical cycles of iron, carbon and sulfur (Fe-C-S) are interrelated. Sulfate reduction in marine sediments is the major factor controlling the cycling and burial of carbon, sulfur and iron. Organoclastic sulfate reduction and anaerobic oxidation of methane (AOM) are the two main processes responsible for sulfate reduction in marine sediments. The amount and reactivity of organic matter, iron minerals and concentrations of dissolved sulfide in pore water control the burial of iron sulfide and organic bound sulfur in marine sediments. Here we investigate the sulfidization process in a sediment core from the western part of upper Bay of Bengal fan characterized by efficient burial of organic matter with siliclastic load. A 30 m long sediment core (MD 161/29, Lat. 170 18.04' N, Long. 870 22.56' E, water depth: 2434m) was collected onboard Marion Dufresne (May, 2007) and studied for Fe-S speciation and organic matter characterization. Buffered dithionite extractable iron (FeD) varies from 0.71 to 1.43 wt % (Avg. 0.79 wt %). FeD represents Fe oxides and oxyhydroxides mainly, ferrihydrite, lepidocrocite, goethite and hematite. Acid volatile sulfur (AVS) varies from 0.0015 to 0.63 wt % (avg: 0.058 wt %), while chromium reducible sulfur (CRS) varies from 0.00047 to 0.29 wt % (avg. 0.054 wt %). Based on the vertical distribution patterns of FeD, AVS and CRS, the core is divided into three zones, the lower (3000 to 1833 cm), middle (1833 to 398 cm) and upper (398 cm to surface) zones. FeD shows higher concentration in the lower zone. FeTR (FeOx + FeD + FeCRS + FeAVS) also exhibit higher concentration in this zone, suggesting higher availability of reactive iron for iron sulfide precipitation. AVS, elemental sulfur, spikes of CRS and gradual enrichment of δ34SAVS and δ34SCRS with sharp peaks in-between is noted in the lower zone. The gradual enrichment of δ34SAVS and δ34SCRS is the outcome of late diagenetic pyritization with higher availability of sulfide (HS- and H2S) from AOM.

Processes controlling the seasonal and spatial variations in sulfate profiles in the pore water of the sediments surrounding Qi'ao Island, Pearl River Estuary, Southern China

NASA Astrophysics Data System (ADS)

Wu, Zijun; Zhou, Huaiyang; Ren, Dezhang; Gao, Hang; Li, Jiangtao

2015-04-01

Marine sediments are the main sink for seawater sulfate and bacterial sulfate reduction is a major component of the global sulfur cycle. Nevertheless, the factors controlling sulfate reduction in the coastal estuary sediments that undergo spatial and temporal variations are still not fully understood. In this study, we measured the concentrations of SO42-, Cl-, CH4, and DIC, and the δ13C of DIC in the pore water of five sampling stations surrounding the Qi'ao Island, Pearl River Estuary, Southern China during the dry season in November 2011 and during the wet season in May 2012. The results showed that the dilution-mixing of the Pearl River with low-concentration sulfate significantly affects the downcore profiles of the sulfate concentrations in the pore water of these estuary sediments. During the wet season, the dilution-mixing of the layers from the top of the sediments to a depth of 14-18 cm occurred at the different sampling stations. In this layer, the sulfate reduction is not appreciable based on the plot of the pore water Cl- and SO42-. Below the dilution-mixing layers, however, sulfate reduction that is driven by the anaerobic oxidation of methane (AOM) occurs. In our comparison, it appeared that the AOM played more important role in the consumption of the pore water sulfate in May 2012 than in November 2011. Meanwhile, we observed a relatively good correlation (r2=0.64) between the depth of the sulfate-methane interface (SMI) and the sulfate concentration in the pore water of the top sediments in dry season, indicating that the pore water sulfate concentration appears to be a primary controlling factor for the depth of the SMI in this estuary. These results highlight the need for an integrated analysis of the hydrologically driven the variations in the sulfate profiles to improve our understanding of the biogeochemical cycling of C, Fe and S and their budgets in estuarine environments.

Nrf2-dependent suppression of azoxymethane/dextran sulfate sodium-induced colon carcinogenesis by the cinnamon-derived dietary factor cinnamaldehyde.

PubMed

Long, Min; Tao, Shasha; Rojo de la Vega, Montserrat; Jiang, Tao; Wen, Qing; Park, Sophia L; Zhang, Donna D; Wondrak, Georg T

2015-05-01

The progressive nature of colorectal cancer and poor prognosis associated with the metastatic phase of the disease create an urgent need for the development of more efficacious strategies targeting colorectal carcinogenesis. Cumulative evidence suggests that the redox-sensitive transcription factor Nrf2 (nuclear factor-E2-related factor 2), a master regulator of the cellular antioxidant defence, represents a promising molecular target for colorectal cancer chemoprevention. Recently, we have identified cinnamon, the ground bark of Cinnamomum aromaticum (cassia cinnamon) and Cinnamomum verum (Ceylon cinnamon), as a rich dietary source of the Nrf2 inducer cinnamaldehyde (CA) eliciting the Nrf2-regulated antioxidant response in human epithelial colon cells, conferring cytoprotection against electrophilic and genotoxic insult. Here, we have explored the molecular mechanism underlying CA-induced Nrf2 activation in colorectal epithelial cells and have examined the chemopreventive potential of CA in a murine colorectal cancer model comparing Nrf2(+/+) with Nrf2(-/-) mice. In HCT116 cells, CA caused a Keap1-C151-dependent increase in Nrf2 protein half-life via blockage of ubiquitination with upregulation of cytoprotective Nrf2 target genes and elevation of cellular glutathione. After optimizing colorectal Nrf2 activation and target gene expression by dietary CA-supplementation regimens, we demonstrated that CA suppresses AOM/DSS-induced inflammatory colon carcinogenesis with modulation of molecular markers of colorectal carcinogenesis. Dietary suppression of colorectal cancer using CA supplementation was achieved in Nrf2(+/+) but not in Nrf2(-/-) mice confirming the Nrf2 dependence of CA-induced chemopreventive effects. Taken together, our data suggest feasibility of colorectal cancer suppression by dietary CA, an FDA-approved food additive derived from the third most consumed spice in the world. ©2015 American Association for Cancer Research.

CHEMOPREVENTIVE EFFICACY OF NAPROXEN AND NO-NAPROXEN IN RODENT MODELS OF COLON, URINARY BLADDER, AND MAMMARY CANCERS

PubMed Central

Steele, Vernon E.; Rao, Chinthalapally V.; Zhang, Yuting; Patlolla, Jagan; Boring, Daniel; Kopelovich, Levy; Juliana, M. Margaret; Grubbs, Clinton J.; Lubet, Ronald A.

2009-01-01

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been highly effective in preventing colon, urinary bladder, and skin cancer preclinically; and also in clinical trials of colon adenoma formation. However, certain NSAIDs cause gastrointestinal (GI) ulceration and may increase cardiovascular (CV) events. Naproxen appears to cause the lowest CV events of the common NSAIDs other than aspirin. NO-naproxen was tested based on the finding that adding a nitric oxide (NO) group to NSAIDs may help alleviate GI toxicity. In the azoxymethane (AOM)-induced rat colon aberrant crypt foci (ACF) model, naproxen administered at 200 and 400 ppm in the diet reduced mean ACFs in the colon by about 45–60%, respectively. NO-naproxen was likewise administered in the diet at roughly equimolar doses (300 and 600 ppm), and reduced total ACF by 20–40%, respectively. In the hydroxybutyl (butyl) nitrosamine (OH-BBN) rat urinary bladder cancer model, NO-naproxen was given at 183 ppm or 550 ppm in the diet, and naproxen at 128 ppm. The NO-naproxen groups had 77% and 73% decreases, respectively, in the development of large urinary bladder tumors, while the 128 ppm naproxen group also showed a strong decrease (69%). If treatments were started three months after OH-BBN, NO-naproxen (550 ppm) and naproxen (400 ppm) were also highly effective (86–94% decreases). In the methylnitrosourea (MNU)-induced mammary cancer model in rats, NO-naproxen and naproxen showed non-significant inhibitions (12 and 24%) at 550 and 400 ppm, respectively. These data show that both naproxen and NO-naproxen are effective agents against urinary bladder and colon, but not mammary, carcinogenesis. PMID:19892664

How does whole ecosystem warming of a peatland affect methane production and consumption?

NASA Astrophysics Data System (ADS)

Hopple, A.; Brunik, K.; Keller, J.; Pfeifer-Meister, L.; Woerndle, G.; Zalman, C.; Hanson, P.; Bridgham, S. D.

2017-12-01

Peatlands are among Earth's most important terrestrial ecosystems due to their massive soil carbon (C) stores and significant release of methane (CH4) into the atmosphere. Methane has a sustained-flux global warming potential 45-times greater than carbon dioxide (CO2), and the accuracy of Earth system model projections relies on our mechanistic understanding of peatland CH4 cycling in the context of environmental change. The objective of this study was to determine, under in situ conditions, how heating of the peat profile affects ecosystem-level anaerobic C cycling. We assessed the response of CO2 and CH4 production, as well as the anaerobic oxidation of CH4 (AOM), in a boreal peatland following 13 months of deep peat heating (DPH) and 16 months of subsequent whole-ecosystem warming (surface and deep heating; WEW) as part of the Spruce and Peatland Responses Under Changing Environments (SPRUCE) project in northern Minnesota, USA. The study uses a regression-based experimental design including 5 temperature treatments that warmed the entire 2 m peat profile from 0 to +9 °C above ambient temperature. Soil cores were collected at multiple depths (25-200 cm) from each experimental chamber at the SPRUCE site and anaerobically incubated at in situ temperatures for 1-2 weeks. Methane and CO2 production in surface peat were positively correlated with elevated temperature, but no consistent temperature response was found at depth (75-200 cm) following DPH. However, during WEW, we observed significant increases in both surface and deep peat methanogenesis with increasing temperature. Surface peat had greater CH4 production rates than deeper peat, implying that the increased CH4 emissions observed in the field were largely driven by surface peat warming. The CO2:CH4 ratio was inversely correlated with temperature across all depths following 16 months of WEW, indicating that the entire peat profile is becoming more methanogenic with warming. We also observed AOM throughout the whole peat profile, with the highest rates observed at the surface and initial data suggesting a positive correlation with increasing temperature. While SPRUCE will continue for many years, our initial results suggest that the vast C stores at depth in peatlands are minimally responsive to warming and any response will be driven largely by surface peat.

Environmental legacy of an underground gas well blowout: long-term effects of gas and brine leakage on groundwater quality

NASA Astrophysics Data System (ADS)

Schout, Gilian; Hartog, Niels; Majid Hassanizadeh, S.; Griffioen, Jasper

2017-04-01

In 1965, a catastrophic underground blowout occurred during the drilling of a gas well in the village of Sleen, the Netherlands. The blowout led to the uncontrolled release of large amounts of natural gas and saline groundwater. Now, 50 years later, a number of nearby groundwater monitoring have been sampled to study the long term effects of this event on the groundwater composition of the overlying freshwater aquifers. The findings are used as an analogue for studying the potential adverse effects of hydraulic fracturing on groundwater quality. In total, 27 samples were taken and analysed for dissolved gas molecular and isotopic composition, major ion chemistry, water isotopes and stable chlorine isotope ratios. The resulting data show that concentrations of dissolved methane are still strongly elevated compared to background samples in a plume downstream of the blowout location. Isotopic data reveals the thermogenic nature of this plume; all samples with methane concentrations greater than 10 mg/l (n=12) had δC-CH4 values greater than -30‰ (VPDB), characteristic of thermogenic methane. The maximum distance at which thermogenic methane is observed is at approximately 500 meter downstream of the centre of the blowout. The progressive enrichment of both δ13C-CH4 and δ2D-CH4, that is observed with distance from the well and decreasing methane concentrations, presents strong evidence for the role of anaerobic methane oxidation (AOM) in limiting the spread of the dissolved methane plume. Low sulphate and increased Fe(II) and Mn(II) concentrations indeed suggest that multiple AOM pathways are involved in the natural attenuation of the dissolved methane plume. Chlorine concentrations were only elevated in a subset of wells in close proximity to the blowout location, indicating that the present-day effects of brine migration are minimal. Nevertheless, elevated Na/Cl ratio's in multiple wells reveal that freshening of the aquifer is still on-going. In summary, this research sheds new light on the long-term effects of natural gas and brine leakage on groundwater quality, which is considered one of the main environmental hazards related to hydraulic fracturing and unconventional gas production in general. Notably, it shows that the anaerobic oxidation of methane may play a major role in containing the effects of uncontrolled gas migration from reservoirs to shallow aquifers.

Open system sulphate reduction in a diagenetic environment - Isotopic analysis of barite (δ34S and δ18O) and pyrite (δ34S) from the Tom and Jason Late Devonian Zn-Pb-Ba deposits, Selwyn Basin, Canada

NASA Astrophysics Data System (ADS)

Magnall, J. M.; Gleeson, S. A.; Stern, R. A.; Newton, R. J.; Poulton, S. W.; Paradis, S.

2016-05-01

Highly positive δ34S values in sulphide minerals are a common feature of shale hosted massive sulphide deposits (SHMS). Often this is attributed to near quantitative consumption of seawater sulphate, and for Paleozoic strata of the Selwyn Basin (Canada), this is thought to occur during bacterial sulphate reduction (BSR) in a restricted, euxinic water column. In this study, we focus on drill-core samples of sulphide and barite mineralisation from two Late Devonian SHMS deposits (Tom and Jason, Macmillan Pass, Selwyn Basin), to evaluate this euxinic basin model. The paragenetic relationship between barite, pyrite and hydrothermal base metal sulphides has been determined using transmitted and reflected light microscopy, and backscatter electron imaging. This petrographic framework provides the context for in-situ isotopic microanalysis (secondary ion mass spectrometry; SIMS) of barite and pyrite. These data are supplemented by analyses of δ34S values for bulk rock pyrite (n = 37) from drill-core samples of un-mineralised (barren), siliceous mudstone, to provide a means by which to evaluate the mass balance of sulphur in the host rock. Three generations of barite have been identified, all of which pre-date hydrothermal input. Isotopically, the three generations of barite have overlapping distributions of δ34S and δ18O values (+22.5‰ to +33.0‰ and +16.4‰ to +18.3‰, respectively) and are consistent with an origin from modified Late Devonian seawater. Radiolarian tests, enriched in barium, are abundant within the siliceous mudstones, providing evidence that primary barium enrichment was associated with biologic activity. We therefore propose that barite formed following remobilisation of productivity-derived barium within the sediment, and precipitated within diagenetic pore fluids close to the sediment water interface. Two generations of pyrite are texturally associated with barite: framboidal pyrite (py-I), which has negative δ34S values (-23‰ to -28‰; n = 9), and euhedral pyrite (py-II), which has markedly more positive δ34S values (+8‰ to +26‰; n = 86). We argue that stratiform pyrite and barite developed along diagenetic redox fronts, where the isotopic relationships (δ34Spyrite ≈ δ34Sbarite) are explained by anaerobic oxidation of methane coupled to sulphate reduction (AOM-SR). Furthermore, the relatively narrow distribution of δ34Sbarite values is consistent with an open system model of sulphate reduction, in which reduced sulphur generation occurred with a reduced isotopic fractionation (ε34S = <15‰) linked to higher rates of sulphate reduction and AOM-SR. Importantly, hydrothermal sulphides (pyrite, sphalerite and galena) all post-date this diagenetic barite-pyrite assemblage, and textural and mineralogical evidence indicates barite replacement to be an important process during hydrothermal mineralisation. Neither the textures nor the documented isotopic relationships can be produced by processes operating in a euxinic water column, which represents a major departure from the conventional model for SHMS formation at Macmillan Pass. We suggest that positive δ34S values in sulphides, a common feature of SHMS systems both in the Selwyn Basin and throughout the geologic record, could be linked to AOM-SR. At Macmillan Pass, positive δ34Spyrite values developed during open system diagenesis, which was critical for rapid sulphur cycling and the development of an effective metal trap.

Prevalence of and risk factors for otitis media with effusion in primary school children: case control study in Erzurum, Turkey.

PubMed

Kucur, Cüneyt; Şimşek, Eda; Kuduban, Ozan; Özbay, İsa

2015-01-01

A total of 1,021 children attending 2 primary schools in districts in Erzurum were enrolled in a study evaluating the prevalence of otitis media with effusion (OME) and its relationship with various risk factors. The prevalence of OME in this study was 6.8% (69/1021). The difference in OME prevalence between age groups (<9 years, >9 years) was statistically significant (p<0.05). Parental smoking (p<0.001), history of acute otitis media (AOM) and recent history of upper respiratory tract infection (URTI) (p<0.001), socioeconomic status (p < 0.05), family size (p<0.001), educational status of the parents (p<0.05) and breastfeeding history (p<0.05) were also statistically significant factors. Sex (p>0.05), consanguineous marriage (p>0.05) and history of hearing loss in the parents (p>0.05) were not statistically significant. Parents need to be informed about the symptoms of and risk factors for OME to avoid delayed diagnosis, which can lead to permanent hearing loss.

Ultrashort pulse CPA-free Ho:YLF linear amplifier

NASA Astrophysics Data System (ADS)

Hinkelmann, Moritz; Wandt, Dieter; Morgner, Uwe; Neumann, Jörg; Kracht, Dietmar

2018-02-01

We present CPA-free linear amplification of 6:3 ps pulses in Ho:YLF crystals up to 100 μJ pulse energy at 10 kHz repetition rate. The seed pulses at a wavelength of 2:05 μm are provided by a Ho-based all-fiber system consisting of a soliton oscillator and a subsequent pre-amplifier followed by a free-space AOM as pulse-picker. Considering the achieved pulse peak power at MW-level, this system is a powerful tool for efficient pumping of parametric amplifiers addressing the highly demanded mid-IR spectral region. In detailed numerical simulations we verified our experimental results and discuss scaling options for pulse duration and energy.

Metagenomics in methane seep detection and studies of the microbial methane sediment filter

NASA Astrophysics Data System (ADS)

Gunn Rike, Anne; Håvelsrud, Othilde Elise; Haverkamp, Thomas; Kristensen, Tom; Jakobsen, Kjetill

2013-04-01

Metanotrophic prokaryotes with their capacity to oxidize methane to biomass and CO2 contribute considerably in reduction of the global methane emission from oceans. Metagenomic studies of seabed sediments represent a new approach to detect marine methane seeps and to study whether the inhabiting microbial consortium represent a microbial methane filter. We have used next generation high throughput DNA sequencing technology to study microbial consortia and their potential metabolic processes in marine sediment samples from the Håkon Mosby mud volcano (HMMV) in the Barents Sea, the Tonya Seep in the Coal Oil Point area in California and from the pockmarked area at the Troll oil and gas field in the North Sea. Annotation of archaeal reads from the HMMV metagenome resulted in hits to all enzymes supposed to be involved in the anaerobic oxidation of methane (AOM) carried out by anaerobic methanotrophic archaea (ANME). The presence of several ANME taxa at HMMV has previously been well described (1). The stratification analysis of the Tonya seep sediment showed that both aerobic and anaerobic methanotrophs were present at both layers investigated, although total archaea, ANME-1, ANME-2 and ANME-3 were overabundant in the deepest layer. Several sulphate reducing taxa (possibly syntrophic ANME partners) were detected. The Tonya Seep sediment represent a robust methane filter where presently dominating methanotrophic taxa could be replaced by less abundant methanotrophs should the environmental conditions change (2). In the Troll pockmarked sediments several methanotrophic taxa including ANME-1, ANME-2 and candidate division NC10 were detected although there was an overabundance of autotrophic nitrifiers (e.g. Nitrosopumilis, Nitrococcus, Nitrospira) using CO2 as the carbon source. Methane migrating upwards through the sediments is probably oxidized to CO2 in AOM resulting in an upward CO2 flux. The CO2 entering the seafloor may contribute to maintain the pockmark structure and represent a carbon source for the autotrophic nitrifying community. In this way the sediments at Troll probably contributes to reduce the methane emissions to the water body and further to the atmosphere (3). References: 1) Niemann H, Lösekann T, Boetius A, Kort R, Amann R. Diversity and distribution of methanotrophic archaea at cold seeps. Appl Environ Microbiol 2005, 71(1), 467-479. 2) Håvelsrud, O. E., Haverkamp, T.H.A., Kristensen, T., Jakobsen, K.S. and Rike A.G. Metagenomic study of methane oxidation in Coal Oil Point seep sediments. BMC Microbiology 2011, 11:221 3) Håvelsrud OE, Haverkamp THA., Kristensen T, Jakobsen KS and Rike AG. Metagenomic and geochemical characterization of pockmarked sediments overlaying the Troll petroleum reservoir in the North Sea. BMC Microbiology 2012, 12:203

Near Infrared Cavity Ring-Down Spectroscopy for Isotopic Analyses of CH4 on Future Martian Surface Missions

NASA Technical Reports Server (NTRS)

Chen, Y.; Mahaffy P.; Holmes, V.; Burris, J.; Morey, P.; Lehmann, K.K.; Lollar, B. Sherwood; Lacrampe-Couloume, G.; Onstott, T.C.

2014-01-01

A compact Near Infrared Continuous Wave Cavity Ring-Down Spectrometer (near-IR-cw-CRDS) was developed as a candidate for future planetary surface missions. The optical cavity was made of titanium with rugged quartz windows to protect the delicate super cavity from the harsh environmental changes that it would experience during space flight and a Martian surface mission. This design assured the long-term stability of the system. The system applied three distributed feedback laser diodes (DFB-LD), two of which were tuned to the absorption line peaks of (sup 12)CH4 and (sup 13)CH4 at 6046.954 inverse centimeters and 6049.121 inverse centimeters, respectively. The third laser was tuned to a spectral-lines-free region for measuring the baseline cavity loss. The multiple laser design compensated for typical baseline drift of a CRDS system and, thus, improved the overall precision. A semiconductor optical amplifier (SOA) was used instead of an Acousto-Optic Module (AOM) to initiate the cavity ring-down events. It maintained high acquisition rates such as AOM, but consumed less power. High data acquisition rates combined with improved long-term stability yielded precise isotopic measurements in this near-IR region even though the strongest CH4 absorption line in this region is 140 times weaker than that of the strongest mid-IR absorption band. The current system has a detection limit of 1.4 times 10( sup –12) inverse centimeters for (sup 13)CH4. This limit corresponds to approximately 7 parts per trillion volume of CH4 at 100 Torrs. With no further improvements the detection limit of our current near IR-cw-CRDS at an ambient Martian pressure of approximately 6 Torrs (8 millibars) would be 0.25 parts per billion volume for one 3.3 minute long analysis.

Efficiently explore the energy landscape of proteins in molecular dynamics simulations by amplifying collective motions

NASA Astrophysics Data System (ADS)

He, Jianbin; Zhang, Zhiyong; Shi, Yunyu; Liu, Haiyan

2003-08-01

We describe a method for efficient sampling of the energy landscape of a protein in atomic molecular dynamics simulations. A simulation is divided into alternatively occurring relaxation phases and excitation phases. In the relaxation phase (conventional simulation), we use a frequently updated reference structure and deviations from this reference structure to mark whether the system has been trapped in a local minimum. In that case, the simulation enters the excitation phase, during which a few slow collective modes of the system are coupled to a higher temperature bath. After the system has escaped from the minimum (also judged by deviations from the reference structure) the simulation reenters the relaxation phase. The collective modes are obtained from a coarse-grained Gaussian elastic network model. The scheme, which we call ACM-AME (amplified collective motion-assisted minimum escaping), is compared with conventional simulations as well as an alternative scheme that elevates the temperature of all degrees of freedom during the excitation phase (amplified overall motion-assisted minimum escaping, or AOM-AME). Comparison is made using simulations on four peptides starting from non-native extended or all helical structures. In terms of sampling low energy conformations and continuously sampling new conformations throughout a simulation, the ACM-AME scheme demonstrates very good performance while the AOM-AME scheme shows little improvement upon conventional simulations. Limited success is achieved in producing structures close to the native structures of the peptides: for an S-peptide analog, the ACM-AME approach is able to reproduce its native helical structure, and starting from an all-helical structure of the villin headpiece subdomain (HP-36) in implicit solvent, two out of three 150 ns ACM-AME runs are able to sample structures with 3-4 Å backbone root-mean-square deviations from the nuclear magnetic resonance structure of the protein.

Segmentation and detection of breast cancer in mammograms combining wavelet analysis and genetic algorithm.

PubMed

Pereira, Danilo Cesar; Ramos, Rodrigo Pereira; do Nascimento, Marcelo Zanchetta

2014-04-01

In Brazil, the National Cancer Institute (INCA) reports more than 50,000 new cases of the disease, with risk of 51 cases per 100,000 women. Radiographic images obtained from mammography equipments are one of the most frequently used techniques for helping in early diagnosis. Due to factors related to cost and professional experience, in the last two decades computer systems to support detection (Computer-Aided Detection - CADe) and diagnosis (Computer-Aided Diagnosis - CADx) have been developed in order to assist experts in detection of abnormalities in their initial stages. Despite the large number of researches on CADe and CADx systems, there is still a need for improved computerized methods. Nowadays, there is a growing concern with the sensitivity and reliability of abnormalities diagnosis in both views of breast mammographic images, namely cranio-caudal (CC) and medio-lateral oblique (MLO). This paper presents a set of computational tools to aid segmentation and detection of mammograms that contained mass or masses in CC and MLO views. An artifact removal algorithm is first implemented followed by an image denoising and gray-level enhancement method based on wavelet transform and Wiener filter. Finally, a method for detection and segmentation of masses using multiple thresholding, wavelet transform and genetic algorithm is employed in mammograms which were randomly selected from the Digital Database for Screening Mammography (DDSM). The developed computer method was quantitatively evaluated using the area overlap metric (AOM). The mean ± standard deviation value of AOM for the proposed method was 79.2 ± 8%. The experiments demonstrate that the proposed method has a strong potential to be used as the basis for mammogram mass segmentation in CC and MLO views. Another important aspect is that the method overcomes the limitation of analyzing only CC and MLO views. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Quantitative geochemical modeling along a transect off Peru: Carbon cycling in time and space, and the triggering factors for carbon loss and storage

NASA Astrophysics Data System (ADS)

Arning, Esther T.; van Berk, Wolfgang; Schulz, Hans-Martin

2012-12-01

Early diagenetic processes in Peruvian shelf and slope sediments are numerically reproduced by applying chemical thermodynamics in a complex, universal approach using the PHREEQC (version 2) computer code. The reaction kinetics of organic carbon remineralization are integrated into a set of equilibrium reactions by defining the type and the amount of converted organic matter in a certain time step. We calculate the most intense remineralization of organic carbon for present-day shelf sites, and the final carbon pool is dominated by secondary carbonates. This serves to highlight the influence of organic matter degradation and anaerobic oxidation of methane (AOM) on diagenetic mineral formation. The enrichment of aqueous methane and the formation of methane hydrate only takes place in slope sediments with high sedimentation rates that prevent diffusive loss of methane (e.g., Sites 682 and 688). Moreover, AOM prevents the diffusion of dissolved methane into overlying seawater. Throughout the Miocene period, these sites were located on a former shelf and the total carbon loss from the sediments was significantly higher in comparison with the present-day. Compared with the present-day shelf site, organic matter remineralization is high, and methane is produced but not stored within the sediments. Our model calculations rule out the possibility of present-day and former shelf site sediments off the coast of Peru as methane reservoirs. Remineralized TOC has to be considered, particularly in older sediments, when interpreting TOC profiles and calculating mass accumulation rates of total organic carbon (MARTOC). The more organic matter has been remineralized during the depositional history, the larger the difference between MARTOC calculated from measured TOC data, and from the sum of modeled and measured TOC data. Consequently, most reliable primary productivity calculations are based on the sum of measured relict TOC and the amount of remineralized organic carbon determined by modeling.

Evidence of functional cell-mediated immune responses to nontypeable Haemophilus influenzae in otitis-prone children

PubMed Central

Seppanen, Elke; Tan, Dino; Corscadden, Karli J.; Currie, Andrew J.; Richmond, Peter C.; Thornton, Ruth B.

2018-01-01

Otitis media (OM) remains a common paediatric disease, despite advances in vaccinology. Susceptibility to recurrent acute OM (rAOM) has been postulated to involve defective cell-mediated immune responses to common otopathogenic bacteria. We compared the composition of peripheral blood mononuclear cells (PBMC) from 20 children with a history of rAOM (otitis-prone) and 20 healthy non-otitis-prone controls, and assessed innate and cell-mediated immune responses to the major otopathogen nontypeable Haemophilus influenzae (NTHi). NTHi was a potent stimulator of inflammatory cytokine secretion from PBMC within 4 hours, with no difference in cytokine levels produced between PBMC from cases or controls. In the absence of antigen stimulation, otitis-prone children had more circulating Natural Killer (NK) cells (p<0.01), particularly NKdim (CD56lo) cells (p<0.01), but fewer CD4+ T cells (p<0.01) than healthy controls. NTHi challenge significantly increased the proportion of activated (CD107a+) NK cells in otitis-prone and non-otitis-prone children (p<0.01), suggesting that NK cells from otitis-prone children are functional and respond to NTHi. CD8+ T cells and NK cells from both cases and controls produced IFNγ in response to polyclonal stimulus (Staphylococcal enterotoxin B; SEB), with more IFNγ+ CD8+ T cells present in cases than controls (p<0.05) but similar proportions of IFNγ+ NK cells. Otitis-prone children had more circulating IFNγ-producing NK cells (p<0.05) and more IFNγ-producing CD4+ (p<0.01) or CD8+ T-cells (p<0.05) than healthy controls. In response to SEB, more CD107a-expressing CD8+ T cells were present in cases than controls (p<0.01). Despite differences in PBMC composition, PBMC from otitis-prone children mounted innate and T cell-mediated responses to NTHi challenge that were comparable to healthy children. These data provide evidence that otitis-prone children do not have impaired functional cell mediated immunity. PMID:29621281

Treatment of Chemotherapy-Induced Peripheral Neuropathy in Integrative Oncology: A Survey of Acupuncture and Oriental Medicine Practitioners.

PubMed

Lu, Zhaoxue; Moody, Jennifer; Marx, Benjamin L; Hammerstrom, Tracy

2017-12-01

Complementary and alternative medicine is increasingly integrated into cancer care. We sought detail on the treatment of chemotherapy-induced peripheral neuropathy (CIPN) with acupuncture and oriental medicine (AOM) by surveying practitioners at integrative oncology (IO) sites across the United States. Online survey of licensed acupuncturists. IO sites in the United States. Fifteen licensed acupuncturists who completed the survey between February 2014 and June 2014. Demographics, IO setting characteristics, AOM treatment characteristics, and practitioner-reported outcomes. Respondents reported an average of 31.3 ± 17.2 patients per week, and one-third (10.1 mean; 7.2 standard deviation [SD]) were treated for CIPN. Medical doctors (86.7%) were the most common providers with whom respondents worked. Traditional Chinese medicine style acupuncture was utilized by a majority of respondents (86.7%), and the most commonly used points were local, typically in the hands and feet, such as Ba Feng, Ba Xie, LV3, and LI4. In addition to acupuncture, nutritional advice was the most frequent auxiliary modality provided by respondents (85.7%). On average, respondents provided 12.75 ± 4.17 treatments for CIPN patients, and a majority (53%) reported treating patients once per week. Timing of the treatments relative to chemotherapy infusion was evenly distributed between "1-2 days after infusion" (60%), "at time of infusion" (53.3%), and "1-2 days before infusion" (46.7%). Sixty percent of respondents rated outcomes as "moderately successful with moderate improvement seen." This survey provides detail regarding IO sites using acupuncture for CIPN as well as real-world treatment patterns, including common point combinations, visit characteristics, and practitioner-reported outcomes. This information contributes to the emerging evidence on the use of acupuncture to address unmet needs of CIPN patients, and supports the development of best practice guidelines for the treatment of CIPN with acupuncture in the IO setting.

Sulfate-dependent Anaerobic Oxidation of Methane as a Generation Mechanism for Calcite Cap Rock in Gulf Coast Salt Domes

NASA Astrophysics Data System (ADS)

Caesar, K. H.; Kyle, R.; Lyons, T. W.; Loyd, S. J.

2015-12-01

Gulf Coast salt domes, specifically their calcite cap rocks, have been widely recognized for their association with significant reserves of crude oil and natural gas. However, the specific microbial reactions that facilitate the precipitation of these cap rocks are still largely unknown. Insight into the mineralization mechanism(s) can be obtained from the specific geochemical signatures recorded in these structures. Gulf Coast cap rocks contain carbonate and sulfur minerals that exhibit variable carbon (d13C) and sulfur isotope (δ34S) signatures. Calcite d13C values are isotopically depleted and show a large range of values from -1 to -52‰, reflecting a mixture of various carbon sources including a substantial methane component. These depleted carbon isotope compositions combined with the presence of abundant sulfide minerals in cap rocks have led to interpretations that invoke microbial sulfate reduction as an important carbonate mineral-yielding process in salt dome environments. Sulfur isotope data from carbonate-associated sulfate (CAS: trace sulfate incorporated within the carbonate mineral crystal lattice) provide a more direct proxy for aqueous sulfate in salt dome systems and may provide a means to directly fingerprint ancient sulfate reduction. We find CAS sulfur isotope compositions (δ34SCAS) significantly greater than those of the precursor Jurassic sulfate-salt deposits (which exhibit δ34S values of ~ +15‰). This implies that cap rock carbonate generation occurred via microbial sulfate reduction under closed-system conditions. The co-occurrence of depleted carbonate d13C values (< ~30‰) and the enriched δ34SCAS values are evidence for sulfate-dependent anaerobic oxidation of methane (AOM). AOM, which has been shown to yield extensive seafloor carbonate authigenesis, is also potentially partly responsible for the carbonate minerals of the Gulf Coast calcite cap rocks through concomitant production of alkalinity. Collectively, these data shed new light on a potential hotspot of microbial activity in the deep biosphere.

Intravital imaging of mouse colonic adenoma using MMP-based molecular probes with multi-channel fluorescence endoscopy.

PubMed

Oh, Gyungseok; Yoo, Su Woong; Jung, Yebin; Ryu, Yeon-Mi; Park, Youngrong; Kim, Sang-Yeob; Kim, Ki Hean; Kim, Sungjee; Myung, Seung-Jae; Chung, Euiheon

2014-05-01

Intravital imaging has provided molecular, cellular and anatomical insight into the study of tumor. Early detection and treatment of gastrointestinal (GI) diseases can be enhanced with specific molecular markers and endoscopic imaging modalities. We present a wide-field multi-channel fluorescence endoscope to screen GI tract for colon cancer using multiple molecular probes targeting matrix metalloproteinases (MMP) conjugated with quantum dots (QD) in AOM/DSS mouse model. MMP9 and MMP14 antibody (Ab)-QD conjugates demonstrate specific binding to colonic adenoma. The average target-to-background (T/B) ratios are 2.10 ± 0.28 and 1.78 ± 0.18 for MMP14 Ab-QD and MMP9 Ab-QD, respectively. The overlap between the two molecular probes is 67.7 ± 8.4%. The presence of false negative indicates that even more number of targeting could increase the sensitivity of overall detection given heterogeneous molecular expression in tumors. Our approach indicates potential for the screening of small or flat lesions that are precancerous.

[Colorectal cancer preventive effect of combined administration of phenolic acids and supercritical extracts from Angelica sinensis].

PubMed

Peng, Yu; Zhao, Bo-Chen; Kang, Qian; Liu, Jia; Chen, Cheng; Li, Bing-Shao; Xie, Yuan-Ping; Wu, Qing

2018-03-01

This study aimed to investigate the colorectal cancer preventive effect of the combined administration of phenolic acids and supercritical extracts from Angelica sinensis. The AOM/DSS model in mice was adopted. Phenolic acids were administrated orally in the initial stage of the model at a dose of 1 g·kg⁻¹ BW, which was combined withtherectal administration with three doses of supercritical extracts (15, 30, 60 g·kg⁻¹ BW). PCNA, 8-oxoguaine, γ-H2AX, iNOS and COX-2 were tested by immunohistochemistry and Western blot assays. The results showed that the combined administration of phenolic acids and supercritical extracts from A. sinensis suppressed the tumor growth and cell proliferation, and DNA damages and inflammatory responses were reduced in a dose-dependent manner. These results indicate that the combined administration of phenolic acids and supercritical extracts from A. sinensis have a certain effect in preventing carcinogenesis. Copyright© by the Chinese Pharmaceutical Association.

Dietary Factors Modulate Colonic Tumorigenesis Through the Interaction of Gut Microbiota and Host Chloride Channels.

PubMed

Zhang, Yong; Kang, Chao; Wang, Xiao-Lan; Zhou, Min; Chen, Meng-Ting; Zhu, Xiao-Hui; Liu, Kai; Wang, Bin; Zhang, Qian-Yong; Zhu, Jun-Dong; Mi, Man-Tian

2018-03-01

In recent decades, the association among diet, gut microbiota, and the risk of colorectal cancer (CRC) has been established. Gut microbiota and associated metabolites, such as bile acids and butyrate, are now known to play a key role in CRC development. The aim of this study is to identify that the progression to CRC is influenced by cholic acid, sodium butyrate, a high-fat diet, or different dose of dihydromyricetin (DMY) interacted with gut microbiota. An AOM/DSS (azoxymethan/dextran sodium sulfate) model is established to study the gut microbiota compsition before and after tumor formation during colitis-induced tumorigenesis. All above dietary factors profoundly influence the composition of gut microbiota and host colonic tumorigenesis. In addition, mice with DMY-modified initial microbiota display different degrees of chemically induced tumorigenesis. Mechanism analysis reveals that gut microbiota-associated chloride channels participated in colon tumorigenesis. Gut microbiota changes occur in the hyperproliferative stage before tumor formation. Gut microbiota and host chloride channels, both of which are regulated by dietary factors, are associated with CRC development. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Gain dynamics of clad-pumped Yb-fiber amplifier and intensity noise control.

PubMed

Zhao, Jian; Guiraud, Germain; Floissat, Florian; Gouhier, Benoit; Rota-Rodrigo, Sergio; Traynor, Nicholas; Santarelli, Giorgio

2017-01-09

Gain dynamics study provides an attractive method to understand the intensity noise behavior in fiber amplifiers. Here, the gain dynamics of a medium power (5 W) clad-pumped Yb-fiber amplifier is experimentally evaluated by measuring the frequency domain transfer functions for the input seed and pump lasers from 10 Hz to 1 MHz. We study gain dynamic behavior of the fiber amplifier in the presence of significant residual pump power (compared to the seed power), showing that the seed transfer function is strongly saturated at low Fourier frequencies while the pump power modulation transfer function is nearly unaffected. The characterization of relative intensity noise (RIN) of the fiber amplifier is well explained by the gain dynamics analysis. Finally, a 600 kHz bandwidth feedback loop using an acoustic-optical modulator (AOM) controlling the seed intensity is successfully demonstrated to suppress the broadband laser intensity noise. A maximum noise reduction of about 30 dB is achieved leading to a RIN of -152 dBc/Hz (~1 kHz-10 MHz) at 2.5 W output power.

Inhibition of Alkaline Flocculation by Algal Organic Matter for Chlorella vulgaris

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vandamme, Dries; Beuckels, Annelies; Vadelius, Eric

2016-01-01

Alkaline flocculation is a promising strategy for the concentration of microalgae for bulk biomass production. However, previous studies have shown that biological changes during the cultivation negatively affect flocculation efficiency. The influence of changes in cell properties and in the quality and composition of algal organic matter (AOM) were studied using Chlorella vulgaris as a model species. In batch cultivation, flocculation was increasingly inhibited over time and mainly influenced by changes in medium composition, rather than biological changes at the cell surface. Total carbohydrate content of the organic matter fraction sized bigger than 3 kDa increased over time and thismore » fraction was shown to be mainly responsible for the inhibition of alkaline flocculation. The monosaccharide identification of this fraction mainly showed the presence of neutral and anionic monosaccharides. An addition of 30–50 mg L -1 alginic acid, as a model for anionic carbohydrate polymers containing uronic acids, resulted in a complete inhibition of flocculation. Furthermore, these results suggest that inhibition of alkaline flocculation was caused by interaction of anionic polysaccharides leading to an increased flocculant demand over time.« less

BIOCHEMICAL COMPOSITION AND NUTRITIONAL EVALUATION OF BARLEY RIHANE (HORDEUM VULGARE L.)

PubMed Central

Lahouar, Lamia; Ghrairi, Fatma; El Arem, Amira; Medimagh, Sana; El Felah, Mouledi; Salem, Hichem Ben; Achour, Lotfi

2017-01-01

Background: Many experimental studies have suggested an important role for barley Rihane(BR)in the prevention of colon cancer and cardiovascular diseases. The objective of this study was to evaluate the physico-chemical properties and nutritional characterizations of BR compared to other varieties grown in Tunisia (Manel, Roho and Tej). Material and Methods: Total, insoluble and soluble dietary fiber(β-glucan), total protein, ash and some minerals of BR and Tunisian barley varieties were determined. Results: The results revealed that BR is good source of dietary fiber mainly β-glucan compared to the other varieties. This variety is a relatively rich source of phosphorous and potassium and it contains many important unsaturated fatty acids. BR has higher nutritional value than other varieties. Conclusion: Barley Rihane has significant nutritional characterizations compared to others Tunisian barleys varieties. Abbreviations: BR, Barley Rihane; LDL, low density lipoprotein; HDL, high density lipoprotein; AOM, azoxymethane; TBV, Tunisian barley varieties; TGW, thousand grain weight; SW, weight specific; TDF, total dietary fiber; IDF, insoluble dietary fiber; SDF, soluble dietary fiber; DM, Dry Matter. PMID:28480409

Energy transfer in the Congo deep-sea fan: From terrestrially-derived organic matter to chemosynthetic food webs

NASA Astrophysics Data System (ADS)

Pruski, A. M.; Decker, C.; Stetten, E.; Vétion, G.; Martinez, P.; Charlier, K.; Senyarich, C.; Olu, K.

2017-08-01

Large amounts of recent terrestrial organic matter (OM) from the African continent are delivered to the abyssal plain by turbidity currents and accumulate in the Congo deep-sea fan. In the recent lobe complex, large clusters of vesicomyid bivalves are found all along the active channel in areas of reduced sediment. These soft-sediment communities resemble those fuelled by chemoautotrophy in cold-seep settings. The aim of this study was to elucidate feeding strategies in these macrofaunal assemblages as part of a greater effort to understand the link between the inputs of terrestrially-derived OM and the chemosynthetic habitats. The biochemical composition of the sedimentary OM was first analysed in order to evaluate how nutritious the available particulate OM is for the benthic macrofauna. The terrestrial OM is already degraded when it reaches the final depositional area. However, high biopolymeric carbon contents (proteins, carbohydrates and lipids) are found in the channel of the recent lobe complex. In addition, about one to two thirds of the nitrogen can be assigned to peptide-like material. Even if this soil-derived OM is poorly digestible, turbiditic deposits contain such high amounts of organic carbon that there is enough biopolymeric carbon and proteacinous nitrogen to support dense benthic communities that contrast with the usual depauperate abyssal plains. Stable carbon and nitrogen isotopes and fatty acid biomarkers were then used to shed light on the feeding strategies allowing the energy transfer from the terrestrial OM brought by the turbidity currents to the abyssal food web. In the non-reduced sediment, surface detritivorous holothurians and suspension-feeding poriferans rely on detritic OM, thereby depending directly on the turbiditic deposits. The sulphur-oxidising symbiont bearing vesicomyids closely depend on the reprocessing of OM with methane and sulphide as final products. Their carbon and nitrogen isotopic signatures vary greatly among sites and could reflect the intensity of the anaerobic oxidation of methane (AOM) in the sediments. Within the vesicomyid habitats, the heterotrophic fauna exhibits a distinctively light carbon isotopic signature in comparison to the background sediments, clearly indicating the utilisation of chemosynthetically-derived OM. Fatty acid biomarkers further confirm that dorvilleid polychaetes consume aggregates that perform AOM. Terrestrial OM reprocessing by microbial consortium thus ensures its transfer to the benthic food web in the Congo deep-sea fan.

Cost-effectiveness analysis of a universal mass vaccination program with a PHiD-CV 2+1 schedule in Malaysia.

PubMed

Wang, Xiao Jun; Saha, Ashwini; Zhang, Xu-Hao

2017-01-01

Currently, two pediatric pneumococcal conjugate vaccines are available in the private market of Malaysia-13-valent pneumococcal conjugate vaccine (PCV13) and pneumococcal polysaccharide and non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV). This study aimed to evaluate the cost-effectiveness of a universal mass vaccination program with a PHiD-CV 2+1 schedule versus no vaccination or with a PCV13 2+1 schedule in Malaysia. A published Markov cohort model was adapted to evaluate the epidemiological and economic consequences of programs with no vaccination, a PHiD-CV 2+1 schedule or a PCV13 2+1 schedule over a 10-year time horizon. Disease cases, deaths, direct medical costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) were estimated. Locally published epidemiology and cost data were used whenever possible. Vaccine effectiveness and disutility data were based on the best available published data. All data inputs and assumptions were validated by local clinical and health economics experts. Analyses were conducted from the perspective of the Malaysian government for a birth cohort of 508,774. Costs and QALYs were discounted at 3% per annum. One-way and probabilistic sensitivity analyses were performed. Compared with no vaccination, a PHiD-CV 2+1 program was projected to prevent 1109 invasive pneumococcal disease (IPD), 24,679 pneumonia and 72,940 acute otitis media (AOM) cases and 103 IPD/pneumonia deaths over 10 years, with additional costs and QALYs of United States dollars (USD) 30.9 million and 1084 QALYs, respectively, at an ICER of USD 28,497/QALY. Compared with a PCV13 2+1 program, PHiD-CV 2+1 was projected to result in similar reductions in IPD cases (40 cases more) but significantly fewer AOM cases (30,001 cases less), with cost savings and additional QALYs gained of USD 5.2 million and 116 QALYs, respectively, demonstrating dominance over PCV13. Results were robust to variations in one-way and probabilistic sensitivity analyses. A PHiD-CV 2+1 universal mass vaccination program could substantially reduce pneumococcal disease burden versus no vaccination, and was expected to be cost-effective in Malaysia. A PHiD-CV 2+1 program was also expected to be a dominant choice over a PCV13 2+1 program in Malaysia.