Whey protein isolate improves acid and bile tolerances of Streptococcus thermophilus ST-M5 and Lactobacillus delbrueckii ssp. bulgaricus LB-12.

PubMed

Vargas, Luis A; Olson, Douglas W; Aryana, Kayanush J

2015-04-01

Acid tolerance and bile tolerance are important probiotic characteristics. Whey proteins contain branched-chain amino acids, which play a role in muscle building and are popular among athletes. Increasing emphasis is being placed on diets containing less carbohydrate, less fat, and more protein. The effect of incremental additions of whey protein isolate (WPI) on probiotic characteristics of pure cultures is not known. The objective of this study was to determine the influence of added WPI on acid tolerance and bile tolerance of pure cultures of Streptococcus thermophilus ST-M5 and Lactobacillus bulgaricus LB-12. The WPI was used at 0 (control), 1, 2 and 3% (wt/vol). Assessment of acid tolerance was conducted on pure cultures at 30-min intervals for 2h of acid exposure and bile tolerance at 1-h intervals for 5h of bile exposure. Use of 1, 2, and 3% WPI improved acid tolerance of Strep. thermophilus ST-M5 and Lb. bulgaricus LB-12. The highest counts for acid tolerance of Strep. thermophilus ST-M5 and Lb. bulgaricus LB-12 were obtained when 3% WPI was used. Use of 2 and 3% WPI improved bile tolerance of Strep. thermophilus ST-M5 and Lb. bulgaricus LB-12 over 5h of bile exposure. The use of WPI is recommended to improve acid and bile tolerance of the yogurt culture bacteria Strep. thermophilus ST-M5 and Lb. bulgaricus LB-12. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Disrupting the biofilm matrix improves wound healing outcomes.

PubMed

Wolcott, R

2015-08-01

The most unyielding molecular component of biofilm communities is the matrix structure that it can create around the individual microbes that constitute the biofilm. The type of polymeric substances (polymeric sugars, bacterial proteins, bacterial DNA and even co-opted host substances) are dependent on the microbial species present within the biofilm. The extracellular polymeric substances that make up the matrix give the wound biofilm incredible colony defences against host immunity, host healing and wound care treatments. This polymeric slime layer, which is secreted by bacteria, encases the population of microbes, creating a physical barrier that limits the ingress of treatment agents to the bacteria. The aim of this study was to determine if degrading the wound biofilm matrix would improve wound healing outcomes and if so, if there was a synergy between treating agents that disrupted biofilm defenses with Next Science Wound Gel (wound gel) and cidal agents (topical antibiotics). A three-armed randomised controlled trial was designed to determine if standard of care (SOC) was superior to SOC plus wound gel (SOC + gel) and wound gel alone. The wound gel used in this study contains components that directly attack the biofilm extracellular polymeric substance. The gel was applied directly to the wound bed on a Monday-Wednesday-Friday interval, either alone or with SOC topical antibiotics. Using a surrogate endpoint of 50% reduction in wound volume, the results showed that SOC healed at 53%, wound gel healed at 80%, while SOC plus wound gel showed 93% of wounds being successfully treated. By directly targeting the wound biofilm matrix, wound healing outcomes are improved.

Microbial effects on the development of forensically important blow fly species.

PubMed

Crooks, Esther R; Bulling, Mark T; Barnes, Kate M

2016-09-01

Colonisation times and development rates of specific blow fly species are used to estimate the minimum Post Mortem Interval (mPMI). The presence or absence of bacteria on a corpse can potentially affect the development and survival of blow fly larvae. Therefore an understanding of microbial-insect interactions is important for improving the interpretation of mPMI estimations. In this study, the effect of two bacteria (Escherichia coli and Staphylococcus aureus) on the growth rate and survival of three forensically important blow fly species (Lucilia sericata, Calliphora vicina and Calliphora vomitoria) was investigated. Sterile larvae were raised in a controlled environment (16:8h day: night light cycle, 23:21°C day: night temperature cycle and a constant 35% relative humidity) on four artificial diets prepared with 100μl of 10(5) CFU bacterial solutions as follows: (1) E. coli, (2) S. aureus, (3) a 50:50 E. coli:S. aureus mix and (4) a sterile bacteria-free control diet. Daily measurements (length, width and weight) were taken from first instar larvae through to the emergence of adult flies. Survival rates were also determined at pupation and adult emergence. Results indicate that bacteria were not essential for the development of any of the blow fly species. However, larval growth rates were affected by bacterial diet, with effects differing between blow fly species. Peak larval weights also varied according to species-diet combination; C. vomitoria had the largest weight on E. coli and mixed diets, C. vicina had the largest weight on S. aureus diets, and treatment had no significant effect on the peak larval weight of L. sericata. These results indicate the potential for the bacteria that larvae are exposed to during development on a corpse to alter both developmental rates and larval weight in some blow fly species. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Epidemiology meets econometrics: using time-series analysis to observe the impact of bed occupancy rates on the spread of multidrug-resistant bacteria.

PubMed

Kaier, K; Meyer, E; Dettenkofer, M; Frank, U

2010-10-01

Two multivariate time-series analyses were carried out to identify the impact of bed occupancy rates, turnover intervals and the average length of hospital stay on the spread of multidrug-resistant bacteria in a teaching hospital. Epidemiological data on the incidences of meticillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum beta-lactamase (ESBL)-producing bacteria were collected. Time-series of bed occupancy rates, turnover intervals and the average length of stay were tested for inclusion in the models as independent variables. Incidence was defined as nosocomial cases per 1000 patient-days. This included all patients infected or colonised with MRSA/ESBL more than 48h after admission. Between January 2003 and July 2008, a mean incidence of 0.15 nosocomial MRSA cases was identified. ESBL was not included in the surveillance until January 2005. Between January 2005 and July 2008 the mean incidence of nosocomial ESBL was also 0.15 cases per 1000 patient-days. The two multivariate models demonstrate a temporal relationship between bed occupancy rates in general wards and the incidence of nosocomial MRSA and ESBL. Similarly, the temporal relationship between the monthly average length of stay in intensive care units (ICUs) and the incidence of nosocomial MRSA and ESBL was demonstrated. Overcrowding in general wards and long periods of ICU stay were identified as factors influencing the spread of multidrug-resistant bacteria in hospital settings. Copyright 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

Potential application of algicidal bacteria for improved lipid recovery with specific algae.

PubMed

Lenneman, Eric M; Wang, Ping; Barney, Brett M

2014-05-01

The utility of specific strains of natural algicidal bacteria isolated from shallow wetland sediments was evaluated against several strains of algae with potential immediate or future commercial value. Two strains of bacteria, Pseudomonas pseudoalcaligenes AD6 and Aeromonas hydrophila AD9, were identified and demonstrated to have algicidal activity against the microalgae Neochloris oleoabundans and Dunaliella tertiolecta. These bacteria were further evaluated for the potential to improve lipid extraction using a mild solvent extraction approach. Aeromonas hydrophila AD9 showed a nearly 12-fold increase in lipid extraction with D. tertiolecta, while both bacteria showed a sixfold improvement in lipid extraction with N. oleoabundans. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Sulphur bacteria mediated formation of Palaeoproterozoic phosphorites

NASA Astrophysics Data System (ADS)

Joosu, Lauri; Lepland, Aivo; Kirsimäe, Kalle

2014-05-01

Modern phosphorite formation is typically associated with high productivity in upwelling areas where apatite (Ca-phosphate) precipitation is mediated by sulphur oxidising bacteria [1]. They inhabit the oxic/anoxic interface within the upper few centimetres of sediment column, accumulating phosphate in their cells under oxic conditions and releasing it rapidly when conditions become anoxic. Sulphur bacteria are known to live in close association with a consortium of anaerobic methane oxidising archaea and syntrophic sulphate-reducing bacteria. Paleoproterozoic, c. 2.0 Ga Zaonega Formation in Karelia, Russia contains several P-rich intervals in the upper part of 1500 m thick succession of organic-rich sedimentary rocks interlayered with mafic tuffs and lavas. Apatite in these P-rich intervals forms impure laminae, lenses and round-oval nodules which diameters typically range from 300 to 1000 μm. Individual apatite particles in P-rich laminae and nodules commonly occur as cylinders that are 1-8 μm long and have diameters of 0.5-4 μm. Cross-sections of best preserved cylindrical apatite particles reveal a thin outer rim whereas the internal parts consist of small anhedral elongated crystallites, intergrown with carbonaceous material. During recrystallization the outer rim thickens towards interior and cylinders may attain hexagonal crystal habit, but their size and shape remains largely unchanged [2]. The sizes of Zaonega nodules are similar to giant sulphide-oxidising bacteria known from modern and ancient settings [3, 4]. Individual apatite cylinders and aggregates have shapes and sizes similar to the methanotrophic archaea that inhabit microbial mats in modern seep/vent areas where they operate in close associations with sulphur-oxidising microbial communities [5]. Seep/vent influence during the Zaonega phosphogenesis is indicated by variable, though positive Eu anomaly, expected in magmatically active sedimentary environment experiencing several lava flows. Moreover, P-rich intervals in the Zaonega Formation are found in organic-rich sediments exhibiting strongly negative δ13Corg values (-37 to -34 per mil) which is interpreted to reflect the methanotrophic biomass. We conclude that modern-style phosphogenesis, mediated by sulphide-oxidising bacteria living in consortium with methanotrophs, was established at least 2 Ga ago. [1] Schulz and Schulz (2005) Science 307, 416-418 [2] Lepland, Joosu, Kirsimäe, Prave, Romashkin, Črne, Martin, Fallick, Somelar, Üpraus, Mänd, Roberts, van Zuilen, Wirth, Schreiber (2014) Nature geoscience 7, 20-24 [3] Bailey, Joye, Kalanetra, Flood, and Corsetti (2007) Nature 445, 198-201 [4] Schulz, Brinkhoff, Ferdelman, Marine, Teske and Jorgensen (1999) Science 284, 493-495 [5] Knittel, Losekann, Boetius, Kort and Amann (2005) Applied and Environmental Microbiology 71, 467-479.

Efficacy of Amitraz plus Metaflumizone for the treatment of canine demodicosis associated with Malassezia pachydermatis

PubMed Central

Tarallo, Viviana D; Lia, Riccardo P; Sasanelli, Mariateresa; Cafarchia, Claudia; Otranto, Domenico

2009-01-01

This case reports the efficacy of metaflumizone plus amitraz spot-on formulation (ProMeris Duo®; Fort Dodge) against generalized demodectic mange. A two year-old male dog presented at clinical examination with poor general condition, diffused alopecia, crusted lesions, pruritus, skin scales and pustules. Demodex mites, Malassezia pachydermatis yeasts and bacteria were diagnosed. The dog was treated with cephalexin and topically with metaflumizone plus amitraz spot on formulation at two weeks intervals until two consecutive skin scrapings resulted negative for mites. The number of adult mites statistically decreased at follow-up with a reduction of approximately 42 and 94% at +14 and +28 days post treatment (p.t.) respectively. Nymphs and larvae could not be detected from +28 day p.t. while eggs were no longer present +42 day p.t. The dog was negative for both bacteria and M. pachydermatis at 14 days p.t., coinciding with improved general clinical conditions, recovering skin lesions and no further signs of pruritus. These results show that metaflumizone plus amitraz associated with the antibiotic therapy is highly effective for treating generalized demodectic mange and could also be effective toward controlling M. pachydermatis opportunistic infections. PMID:19265536

Clinical and microbiological effects of levofloxacin in the treatment of chronic periodontitis: a randomized, placebo-controlled clinical trial.

PubMed

Pradeep, Avani R; Singh, Sonender P; Martande, Santosh S; Naik, Savitha B; N, Priyanka; Kalra, Nitish; Suke, Deepak K

2015-08-01

The aim of the present study was to evaluate the clinical and microbiological effect of systemic levofloxacin (LFX) as an adjunct to scaling and root planing (SRP) in patients with chronic periodontitis (CP). Sixty-five patients with CP were randomly divided into a test (n = 33, SRP and LFX 500 mg, once daily [o.d.]) and a control group (n = 32, SRP and placebo, o.d.). Plaque index (PI), gingival index (GI), percentage of sites with bleeding on probing (%BoP), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline, 10 days, and 1-, 3-, and 6-month intervals. The percentage of sites positive for Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis, and Tannerella forsythia were recorded at baseline and at 3 and 6 months. Patients receiving LFX showed statistically-significant improvements in mean PD and CAL. The intergroup difference in PI, GI, and%BoP was not significant at any interval. There was a reduction in the percentage of sites positive for periodontopathic bacteria over the duration of the study in both groups, and a statistically-significant reduction in the number of sites positive for A. actinomycetemcomitans in the LFX group (P < 0.001). Levofloxacin was found to significantly improve the clinical and microbiological parameters in CP individuals. © 2014 Wiley Publishing Asia Pty Ltd.

Assessment of Environmental Contamination with Pathogenic Bacteria at a Hospital Laundry Facility.

PubMed

Michael, Karen E; No, David; Daniell, William E; Seixas, Noah S; Roberts, Marilyn C

2017-11-10

Little is known about exposure to pathogenic bacteria among industrial laundry workers who work with soiled clinical linen. To study worker exposures, an assessment of surface contamination was performed at an industrial laundry facility serving hospitals in Seattle, WA, USA. Surface swab samples (n = 240) from the environment were collected during four site visits at 3-month intervals. These samples were cultured for Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Voluntary participation of 23 employees consisted of nasal swabs for detection of MRSA, observations during work, and questionnaires. Contamination with all three pathogens was observed in both dirty (laundry handling prior to washing) and clean areas (subsequent to washing). The dirty area had higher odds of overall contamination (≥1 pathogen) than the clean area (odds ratio, OR = 18.0, 95% confidence interval 8.9-36.5, P < 0.001). The odds of contamination were high for each individual pathogen: C. difficile, OR = 15.5; MRSA, OR = 14.8; and VRE, OR = 12.6 (each, P < 0.001). The highest odds of finding surface contamination occurred in the primary and secondary sort areas where soiled linens were manually sorted by employees (OR = 63.0, P < 0.001). The study substantiates that the laundry facility environment can become contaminated by soiled linens. Workers who handle soiled linen may have a higher risk of exposure to C. difficile, MRSA, and VRE than those who handle clean linens. Improved protocols for prevention and reduction of environmental contamination were implemented because of this study. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Genetic Diversity and Association Characters of Bacteria Isolated from Arbuscular Mycorrhizal Fungal Spore Walls

PubMed Central

Selvakumar, Gopal; Krishnamoorthy, Ramasamy; Kim, Kiyoon; Sa, Tong-Min

2016-01-01

Association between arbuscular mycorrhizal fungi (AMF) and bacteria has long been studied. However, the factors influencing their association in the natural environment is still unknown. This study aimed to isolate bacteria associated with spore walls of AMF and identify their potential characters for association. Spores collected from coastal reclamation land were differentiated based on their morphology and identified by 18S rDNA sequencing as Funneliformis caledonium, Racocetra alborosea and Funneliformis mosseae. Bacteria associated with AMF spore walls were isolated after treating them with disinfection solution at different time intervals. After 0, 10 and 20 min of spore disinfection, 86, 24 and 10 spore associated bacteria (SAB) were isolated, respectively. BOX-PCR fingerprinting analysis showed that diverse bacterial communities were associated to AMF spores. Bacteria belonging to the same genera could associate with different AMF spores. Gram positive bacteria were more closely associated with AMF spores. Isolated SAB were characterized and tested for spore association characters such as chitinase, protease, cellulase enzymes and exopolysaccharide production (EPS). Among the 120 SAB, 113 SAB were able to show one or more characters for association and seven SAB did not show any association characters. The 16S rDNA sequence of SAB revealed that bacteria belonging to the phyla Firmicutes, Proteobacteria, Actinobacteria and Bactereiodes were associated with AMF spore walls. PMID:27479250

Vegetation successfully prevents oxidization of sulfide minerals in mine tailings.

PubMed

Li, Yang; Sun, Qingye; Zhan, Jing; Yang, Yang; Wang, Dan

2016-07-15

The oxidization of metal sulfide in tailings causes acid mine drainage. However, it remains unclear whether vegetation prevents the oxidization of metal sulfides. The oxidization characteristics and microbial indices of the tailings in the presence of various plant species were investigated to explore the effects of vegetation on the oxidization of sulfide minerals in tailings. The pH, reducing sulfur, free iron oxides (Fed), chemical oxygen consumption (COC) and biological oxygen consumption (BOC) were measured. Key iron- and sulfur-oxidizing bacteria (Acidithiobacillus spp., Leptospirillum spp. and Thiobacillus spp.) were quantified using real-time PCR. The results indicate that vegetation growing on tailings can effectively prevent the oxidization of sulfide minerals in tailings. A higher pH and reducing-sulfur content and lower Fed were observed in the 0-30 cm depth interval in the presence of vegetation compared to bare tailings (BT). The COC gradually decreased with depth in all of the soil profiles; specifically, the COC rapidly decreased in the 10-20 cm interval in the presence of vegetation but gradually decreased in the BT profiles. Imperata cylindrica (IC) and Chrysopogon zizanoides (CZ) profiles contained the highest BOC in the 10-20 cm interval. The abundance of key iron- and sulfur-oxidizing bacteria in the vegetated tailings were significantly lower than in the BT; in particular, IC was associated with the lowest iron- and sulfur-oxidizing bacterial abundance. In conclusion, vegetation successfully prevented the oxidization of sulfide minerals in the tailings, and Imperata cylindrica is the most effective in reducing the number of iron- and sulfur-oxidizing bacteria and helped to prevent the oxidization of sulfide minerals in the long term. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of hygienic critical control points in boar semen production.

PubMed

Schulze, M; Ammon, C; Rüdiger, K; Jung, M; Grobbel, M

2015-02-01

The present study addresses the microbiological results of a quality control audit in artificial insemination (AI) boar studs in Germany and Austria. The raw and processed semen of 344 boars in 24 AI boar studs were analyzed. Bacteria were found in 26% (88 of 344) of the extended ejaculates and 66.7% (18 of 24) of the boar studs. The bacterial species found in the AI dose were not cultured from the respective raw semen in 95.5% (84 of 88) of the positive samples. These data, together with the fact that in most cases all the samples from one stud were contaminated with identical bacteria (species and resistance profile), indicate contamination during processing. Microbiological investigations of the equipment and the laboratory environment during semen processing in 21 AI boar studs revealed nine hygienic critical control points (HCCP), which were addressed after the first audit. On the basis of the analysis of the contamination rates of the ejaculate samples, improvements in the hygiene status were already present in the second audit (P = 0.0343, F-test). Significant differences were observed for heating cabinets (improvement, P = 0.0388) and manual operating elements (improvement, P = 0.0002). The odds ratio of finding contaminated ejaculates in the first and second audit was 1.68 (with the 95% confidence interval ranging from 1.04 to 2.69). Furthermore, an overall good hygienic status was shown for extenders, the inner face of dilution tank lids, dyes, and ultrapure water treatment plants. Among the nine HCCP considered, the most heavily contaminated samples, as assessed by the median scores throughout all the studs, were found in the sinks and/or drains. High numbers (>10(3) colony-forming units/cm(2)) of bacteria were found in the heating cabinets, ejaculate transfer, manual operating elements, and laboratory surfaces. In conclusion, the present study emphasizes the need for both training of the laboratory staff in monitoring HCCP in routine semen production and audits in such AI centers for the external control of hygiene parameters. Copyright © 2015 Elsevier Inc. All rights reserved.

Combating Antibiotic Resistance

MedlinePlus

... and improved tests for infectious diseases. Antibiotics Fight Bacteria, Not Viruses Antibiotics are meant to be used ... treat strep throat, which is caused by streptococcal bacteria, and skin infections caused by staphylococcal bacteria. Although ...

Risk factors for carbapenem-resistant Acinetobacter baumannii infections at a tertiary care hospital in New Caledonia, South Pacific.

PubMed

Le Hello, Simon; Falcot, Virginie; Lacassin, Flore; Mikulski, Marc; Baumann, Francine

2010-12-01

In New Caledonia, South Pacific, Acinetobacter baumannii is a nosocomial pathogen. OXA-23 carbapenem-resistant A. baumannii (CRAB) has been ranked third among all multidrug-resistant (MDR) bacteria at the main hospital of Nouméa in New Caledonia (24.8%, 50/202 isolates). In the present study, risk factors and outcomes for 50 patients with CRAB infection were compared with those of 152 patients infected with other MDR bacteria. Independent risk factors for infection with CRAB were respiratory ward admission (odds ratio 2.8, 95% confidence interval 1.1-7.1) and previous treatment with quinolones, β-lactams and anti-MRSA antibiotics. The 30-day mortality was higher for CRAB infections compared with other MDR infections (14% vs 3.3%, p = 0.006). These findings highlight the importance of knowing specific local characteristics relating to the ecology and patterns of resistance of MDR bacteria so as to avoid the emergence of unexpected pan-resistant bacteria.

Bacterial detection using bacteriophages and gold nanorods by following time-dependent changes in Raman spectral signals.

PubMed

Moghtader, Farzaneh; Tomak, Aysel; Zareie, Hadi M; Piskin, Erhan

2018-03-27

This study attemps to develop bacterial detection strategies using bacteriophages and gold nanorods (GNRs) by Raman spectral analysis. Escherichia coli was selected as the target and its specific phage was used as the bioprobe. Target bacteria and phages were propagated/purified by traditional techniques. GNRs were synthesized by using hexadecyltrimethyl ammonium bromide (CTAB) as stabilizer. A two-step detection strategy was applied: Firstly, the target bacteria were interacted with GNRs in suspensions, and then they were dropped onto silica substrates for detection. It was possible to obtain clear surface-enchanced Raman spectroscopy (SERS) peaks of the target bacteria, even without using phages. In the second step, the phage nanoemulsions were droped onto the bacterial-GNRs complexes on those surfaces and time-dependent changes in the Raman spectra were monitored at different time intervals upto 40 min. These results demonstrated that how one can apply phages with plasmonic nanoparticles for detection of pathogenic bacteria very effectively in a quite simple test.

Initial use of one or two antibiotics for critically ill patients with community-acquired pneumonia: impact on survival and bacterial resistance.

PubMed

Adrie, Christophe; Schwebel, Carole; Garrouste-Orgeas, Maïté; Vignoud, Lucile; Planquette, Benjamin; Azoulay, Elie; Kallel, Hatem; Darmon, Michael; Souweine, Bertrand; Dinh-Xuan, Anh-Tuan; Jamali, Samir; Zahar, Jean-Ralph; Timsit, Jean-François

2013-11-07

Several guidelines recommend initial empirical treatment with two antibiotics instead of one to decrease mortality in community-acquired pneumonia (CAP) requiring intensive-care-unit (ICU) admission. We compared the impact on 60-day mortality of using one or two antibiotics. We also compared the rates of nosocomial pneumonia and multidrug-resistant bacteria. This is an observational cohort study of 956 immunocompetent patients with CAP admitted to ICUs in France and entered into a prospective database between 1997 and 2010. Initial adequate antibiotic therapy was significantly associated with better survival (subdistribution hazard ratio (sHR), 0.63; 95% confidence interval (95% CI), 0.42 to 0.94; P = 0.02); this effect was strongest in patients with Streptococcus pneumonia CAP (sHR, 0.05; 95% CI, 0.005 to 0.46; p = 0.001) or septic shock (sHR: 0.62; 95% CI 0.38 to 1.00; p = 0.05). Dual therapy was associated with a higher frequency of initial adequate antibiotic therapy. However, no difference in 60-day mortality was found between monotherapy (β-lactam) and either of the two dual-therapy groups (β-lactam plus macrolide or fluoroquinolone). The rates of nosocomial pneumonia and multidrug-resistant bacteria were not significantly different across these three groups. Initial adequate antibiotic therapy markedly decreased 60-day mortality. Dual therapy improved the likelihood of initial adequate therapy but did not predict decreased 60-day mortality. Dual therapy did not increase the risk of nosocomial pneumonia or multidrug-resistant bacteria.

Plasma antibodies to oral bacteria and risk of pancreatic cancer in a large European prospective cohort study

PubMed Central

Michaud, Dominique S.; Izard, Jacques; Wilhelm-Benartzi, Charlotte S.; You, Doo-Ho; Grote, Verena A; Tjønneland, Anne; Dahm, Christina C.; Overvad, Kim; Jenab, Mazda; Fedirko, Veronika; Boutron-Ruault, Marie Christine; Clavel-Chapelon, Françoise; Racine, Antoine; Kaaks, Rudolf; Boeing, Heiner; Foerster, Jana; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; Sacerdote, Carlotta; Sieri, Sabina; Palli, Domenico; Tumino, Rosario; Panico, Salvatore; Siersema, Peter; Peeters, Petra HM; Lund, Eiliv; Barricarte, Aurelio; Huerta, José-María; Molina-Montes, Esther; Dorronsoro, Miren; Quirós, J. Ramón; Duell, Eric J.; Ye, Weimin; Sund, Malin; Lindkvist, Björn; Johansen, Dorthe; Khaw, Kay-Tee; Wareham, Nick; Travis, Ruth C.; Vineis, Paolo; Bueno-de-Mesquita, H. Bas; Riboli, Elio

2013-01-01

Objective Examine the relationship between antibodies to 25 oral bacteria and pancreatic cancer risk in a prospective cohort study. Design We measured antibodies to oral bacteria in prediagnosis blood samples from 405 pancreatic cancer cases and 416 matched controls, nested within the European Prospective Investigation into Cancer and Nutrition study (EPIC). Analyses were conducted using conditional logistic regression and additionally adjusted for smoking status and body mass index. Results Individuals with high levels of antibodies against Porphyromonas gingivalis ATTC 53978, a pathogenic periodontal bacteria, had a 2-fold higher risk of pancreatic cancer than individuals lower levels of these antibodies (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.05–4.36; >200 ng/ml vs ≤200 ng/ml). To explore the association with commensal (non-pathogenic) oral bacteria, we performed a cluster analysis and identified 2 groups of individuals, based on their antibody profiles. A cluster with overall higher levels of antibodies had a 45% lower risk of pancreatic cancer than a cluster with overall lower levels of antibodies (OR, 0.55; 95% CI, 0.36–0.83). Conclusion Periodontal disease might increase the risk for pancreatic cancer. Moreover, increased levels of antibodies against specific commensal oral bacteria, which can inhibit growth of pathogenic bacteria, might reduce the risk of pancreatic cancer. Studies are needed to determine whether oral bacteria have direct effects on pancreatic cancer pathogenesis or serve as markers of the immune response. PMID:22990306

An improved clenbuterol detection by immunochromatographic assay with bacteria@Au composite as signal amplifier.

PubMed

Huang, Qiong; Bu, Tong; Zhang, Wentao; Yan, Lingzhi; Zhang, Mengyue; Yang, Qingfeng; Huang, Lunjie; Yang, Baowei; Hu, Na; Suo, Yourui; Wang, Jianlong; Zhang, Daohong

2018-10-01

Immunochromatographic assays (ICAs) are most frequently used for on-site rapid screening of clenbuterol. To improve sensitivity, a novel probe with bacteria as signal carriers was developed. Bacteria can load a great deal of gold nanoparticles (AuNPs) on their surface, meaning much fewer antibodies are needed to produce clearly visible results, although low concentrations of antibody could also trigger fierce competition between free analyte and the immobilized antigen. Thus, a limited number of antibodies was key to significantly improved sensitivity. Analytical conditions, including bacterial species, coupling method, and concentration, were optimized. The visual detection limit (VDL) for clenbuterol was 0.1 ng/mL, a 20-fold improvement in sensitivity compared with traditional strips. This work has opened up a new route for signal amplification and improved performance of ICAs. Furthermore, inactivated bacteria could also be environment-friendly and robust signal carriers for other biosensors. Copyright © 2018 Elsevier Ltd. All rights reserved.

Airborne Bacteria in an Urban Environment

PubMed Central

Mancinelli, Rocco L.; Shulls, Wells A.

1978-01-01

Samples were taken at random intervals over a 2-year period from urban air and tested for viable bacteria. The number of bacteria in each sample was determined, and each organism isolated was identified by its morphological and biochemical characteristics. The number of bacteria found ranged from 0.013 to 1.88 organisms per liter of air sampled. Representatives of 19 different genera were found in 21 samples. The most frequently isolated organisms and their percent of occurence were Micrococcus (41%), Staphylococcus (11%), and Aerococcus (8%). The bacteria isolated were correlated with various weather and air pollution parameters using the Pearson product-moment correlation coefficient method. Statistically significant correlations were found between the number of viable bacteria isolated and the concentrations of nitric oxide (−0.45), nitrogen dioxide (+0.43), and suspended particulate pollutants (+0.56). Calculated individually, the total number of Micrococcus, Aerococcus, and Staphylococcus, number of rods, and number of cocci isolated showed negative correlations with nitric oxide and positive correlations with nitrogen dioxide and particulates. Statistically significant positive correlations were found between the total number of rods isolated and the concentration of nitrogen dioxide (+0.54) and the percent relative humidity (+0.43). The other parameters tested, sulfur dioxide, hydrocarbons, and temperature, showed no significant correlations. Images PMID:677875

Periodontal disease associated with red complex bacteria in dogs.

PubMed

Di Bello, A; Buonavoglia, A; Franchini, D; Valastro, C; Ventrella, G; Greco, M F; Corrente, M

2014-03-01

Red complex bacteria (Treponema denticola, Tannerella forsythia and Porphyromonas gingivalis) play a major role in the aetiology of periodontal disease in humans. This study was designed to evaluate the association of such bacteria with periodontal disease in dogs. Seventy-three subgingival samples taken from dogs ranging from 2 months to 12 years (median age 4 years) were tested for red complex bacteria using a polymerase chain reaction assay. Thirty-six of 73 (49 · 3%) dogs were found to be positive for T. forsythia and P. gingivalis. Dogs with gingivitis or periodontitis were more likely to be infected with T. forsythia and P. gingivalis [odds ratio (OR) 5 · 4 (confidence interval (CI) 1 · 9-15 · 6), P = 0 · 002] than healthy animals. Only 3 (4 · 1%) of 73 samples were positive for red complex bacteria, but the association with periodontal disease was not significant. The results indicate that involvement of red complex bacteria in periodontal disease in dogs is similar to that observed in humans. Only the concurrent presence of T. forsythia and P. gingivalis were correlated to periodontal disease in dogs in this study. © 2014 British Small Animal Veterinary Association.

Effect of aminglycoside administration on the occurrence and multiplication of resistant bacteria.

PubMed

Milas, Josip; Kalenić, Smilja; Milas, Vesna; Miskulin, Maja; Vuković, Dubravka; Rudan, Stjepan; Puntarić, Dinko

2009-06-01

In the prospective study the susceptibility of 41 Escherichia coli strains and 55 Pseudomonas aeruginosa strains to gentamicin, netilmicin and amikacin was tested at a 2-year interval (period I April 1998 to March 1999, and period II April to July 2001). Genotyping was performed by pulsed-field gel electrophoresis, and a clone based on 80% or 90% similarity was determined for each of the study bacteria. In 24 (32.0%) clones, strains showed no variation over 2-year interval, supporting the hypothesis on a priori susceptible strains. Transformation from susceptibility in period I to resistance in period II was demonstrated in 5 (6.7%) clones, a pattern consistent with the concept of bacterial development of resistance under the influence of antibiotics. However, there were 10 (13.3%) clones whose strains exhibited an inverse pattern. Accordingly, two-way transformation of susceptibility took place during the study period. The utilization of the study aminoglycosides had no major impact on the variation of microbial susceptibility. Changes in microbial susceptibility were found to follow some regular patterns, which were not influenced by the study aminoglycosides. Two phenomena were observed: (i) there were stable clones that did not develop resistance in spite of selective antibiotic challenge; and (ii) changes of susceptibility in isolated bacteria from both inpatient and outpatient strains of the same clone were two-way and reversible.

Bacterial communities of tyre monofill sites: growth on tyre shreds and leachate.

PubMed

Vukanti, R; Crissman, M; Leff, L G; Leff, A A

2009-06-01

To investigate bacterial communities of tyre monofill sites, colonization of tyre material by bacteria and the effect of tyre leachate on bacteria. Culturable bacteria were isolated from buried tyre shreds and identified using fatty acid methyl ester analysis. Isolates belonged to taxonomic groups such as Bacilli, Actinobacteria, Clostridia, Flavobacteria, beta and gamma-proteobacteria. For tyre material colonization experiments, Bacillus megatarium, Bacillus cereus, Hydrogenophaga flava, Janthinobacterium lividum, Cellulosimicrobium cellulans, Arthrobacter globiformis (isolated from tyre shreds or leachate at the study site); Escherichia coli and Acidithiobacillus ferrooxidans were used. Beakers containing tyre shreds and artificial rain water were inoculated with a given bacterial culture, incubated at room temperature and sampled at regular intervals. 4',6-diamidino-2-phenylindole (DAPI) staining followed by epifluorescent microscopy was used to enumerate bacteria in samples. Of the bacteria tested, B. megatarium, J. lividum, E. coli, C. cellulans and A. globiformis exhibited the most extensive colonization of the tyre shreds. However, the extent of colonization varied among bacteria. Response to tyre leachate was also examined using B. cereus and J. lividum. Both bacteria increased in abundance due to the addition of leachate. Bacteria associated with buried tyre shreds were identified and found to include typical soil and freshwater organisms. The majority of indigenous isolates grew on tyre material (or leachate) suggesting that they play an active role in the ecology of these sites and that their potential role in tyre degradation should be explored. This study provides information on bacterial communities of tyre-waste disposal sites, explores the interaction between tyre material and bacteria and identifies bacteria that could be involved in or employed for recycling tyre-waste.

Fluorescence spectroscopy for rapid detection and classification of bacterial pathogens.

PubMed

Sohn, Miryeong; Himmelsbach, David S; Barton, Franklin E; Fedorka-Cray, Paula J

2009-11-01

This study deals with the rapid detection and differentiation of Escherichia coli, Salmonella, and Campylobacter, which are the most commonly identified commensal and pathogenic bacteria in foods, using fluorescence spectroscopy and multivariate analysis. Each bacterial sample cultured under controlled conditions was diluted in physiologic saline for analysis. Fluorescence spectra were collected over a range of 200-700 nm with 0.5 nm intervals on the PerkinElmer Fluorescence Spectrometer. The synchronous scan technique was employed to find the optimum excitation (lambda(ex)) and emission (lambda(em)) wavelengths for individual bacteria with the wavelength interval (Deltalambda) being varied from 10 to 200 nm. The synchronous spectra and two-dimensional plots showed two maximum lambda(ex) values at 225 nm and 280 nm and one maximum lambda(em) at 335-345 nm (lambda(em) = lambda(ex) + Deltalambda), which correspond to the lambda(ex) = 225 nm, Deltalambda = 110-120 nm, and lambda(ex) = 280 nm, Deltalambda = 60-65 nm. For all three bacterial genera, the same synchronous scan results were obtained. The emission spectra from the three bacteria groups were very similar, creating difficulty in classification. However, the application of principal component analysis (PCA) to the fluorescence spectra resulted in successful classification of the bacteria by their genus as well as determining their concentration. The detection limit was approximately 10(3)-10(4) cells/mL for each bacterial sample. These results demonstrated that fluorescence spectroscopy, when coupled with PCA processing, has the potential to detect and to classify bacterial pathogens in liquids. The methodology is rapid (>10 min), inexpensive, and requires minimal sample preparation compared to standard analytical methods for bacterial detection.

Exploration of indigenous bacteria in an intensive aquaculture system of African catfish (Clarias sp.) in Banyuwangi, Indonesia

NASA Astrophysics Data System (ADS)

Prayogo; Rahardja, B. S.; Asshanti, A. N.; Dewi, N. N.; Santanumurti, M. B.

2018-04-01

Intensive African catfish culture in tarpaulin pond was popular in Banyuwangi, Indonesia since the government supported the fisheries sector. Unfortunately, the failure of African catfish culture still occurred since the waste from fish metabolite process and feed residue decreased the water quality. Bacteria in the water could be the solution to increase the success rate of aquaculture by improving the water quality. This study purpose was to obtained indigenous bacteria in intensive aquaculture system of African catfish to improve water quality. This study successfully isolated bacteria contained with amylase, protease and lipase characteristic. Isolated bacteria in this study were identified as Pseudomonas pseudomallei (97.81%), Bacillus subtilis (95.81%) and Pseudomonas stutzeri (61.21%).

Plant probiotic bacteria Bacillus and Paraburkholderia improve growth, yield and content of antioxidants in strawberry fruit.

PubMed

Rahman, Mosaddiqur; Sabir, Abdullah As; Mukta, Julakha Akter; Khan, Md Mohibul Alam; Mohi-Ud-Din, Mohammed; Miah, Md Giashuddin; Rahman, Mahfuzur; Islam, M Tofazzal

2018-02-06

Strawberry is an excellent source of natural antioxidants with high capacity of scavenging free radicals. This study evaluated the effects of two plant probiotic bacteria, Bacillus amylolequefaciens BChi1 and Paraburkholderia fungorum BRRh-4 on growth, fruit yield and antioxidant contents in strawberry fruits. Root dipping of seedlings (plug plants) followed by spray applications of both probiotic bacteria in the field on foliage significantly increased fruit yield (up to 48%) over non-treated control. Enhanced fruit yield likely to be linked with higher root and shoot growth, individual and total fruit weight/plant and production of phytohormone by the probiotic bacteria applied on plants. Interestingly, the fruits from plants inoculated with the isolates BChi1 and BRRh-4 had significantly higher contents of phenolics, carotenoids, flavonoids and anthocyanins over non-treated control. Total antioxidant activities were also significantly higher (p < 0.05) in fruits of strawberry plants treated with both probiotic bacteria. To the best of our knowledge, this is the first report of significant improvement of both yield and quality of strawberry fruits by the application of plant probiotic bacteria BChi1 and BRRh-4 in a field condition. Further study is needed to elucidate underlying mechanism of growth and quality improvement of strawberry fruits by probiotic bacteria.

Preliminary observations on the concentration of marine bacteriophages in the water around Helgoland

NASA Astrophysics Data System (ADS)

Moebus, K.

1991-12-01

In a preliminary survey, conducted between August 28 and October 9, 1990, the concentration of bacteriophages in seawater sampled at intervals of 1 to 4 days near Helgoland (station Kabeltonne) was determined by using indicator bacteria which had been isolated from seawater sampled only some weeks before. With a number of bacterial strains, phage concentrations ranging between 2 and 7×102ml-1 were found. However, during the course of this investigation maximal concentrations lasted for a few days only. With most indicator bacteria employed, the concentration of plaque-forming units (PFU) varied in the range of <1 and 20 30 PFU ml-1.

Multicenter intervention program to increase adherence to hand hygiene recommendations and glove use and to reduce the incidence of antimicrobial resistance.

PubMed

Trick, William E; Vernon, Michael O; Welbel, Sharon F; Demarais, Patricia; Hayden, Mary K; Weinstein, Robert A

2007-01-01

To determine whether a multimodal intervention could improve adherence to hand hygiene and glove use recommendations and decrease the incidence of antimicrobial resistance in different types of healthcare facilities. Prospective, observational study performed from October 1, 1999, through December 31, 2002. We monitored adherence to hand hygiene and glove use recommendations and the incidence of antimicrobial-resistant bacteria among isolates from clinical cultures. We evaluated trends in and predictors for adherence and preferential use of alcohol-based hand rubs, using multivariable analyses. Three intervention hospitals (a 660-bed acute and long-term care hospital, a 120-bed community hospital, and a 600-bed public teaching hospital) and a control hospital (a 700-bed university teaching hospital).Intervention. At the intervention hospitals, we introduced or increased the availability of alcohol-based hand rub, initiated an interactive education program, and developed a poster campaign; at the control hospital, we only increased the availability of alcohol-based hand rub. We observed 6,948 hand hygiene opportunities. The frequency of hand hygiene performance or glove use significantly increased during the study period at the intervention hospitals but not at the control hospital; the maximum quarterly frequency of hand hygiene performance or glove use at intervention hospitals (74%, 80%, and 77%) was higher than that at the control hospital (59%). By multivariable analysis, preferential use of alcohol-based hand rubs rather than soap and water for hand hygiene was more likely among workers at intervention hospitals compared with nonintervention hospitals (adjusted odds ratio, 4.6 [95% confidence interval, 3.3-6.4]) and more likely among physicians (adjusted odds ratio, 1.4 [95% confidence interval, 1.2-1.8]) than among nurses at intervention hospitals. A significantly reduced incidence of antimicrobial-resistant bacteria among isolates from clinical culture was found at a single intervention hospital, which had the greatest increase in the frequency of hand hygiene performance. During a 3-year period, a multimodal intervention program increased adherence to hand hygiene recommendations, especially to the use of alcohol-based hand rubs. In one hospital, a concomitant reduction was found in the incidence of antimicrobial-resistant bacteria among isolates from clinical cultures.

Characterization of the volatile profile of Antarctic bacteria by using solid-phase microextraction-gas chromatography-mass spectrometry.

PubMed

Romoli, Riccardo; Papaleo, Maria Cristiana; de Pascale, Donatella; Tutino, Maria Luisa; Michaud, Luigi; LoGiudice, Angelina; Fani, Renato; Bartolucci, Gianluca

2011-10-01

Bacteria belonging to the Burkholderia cepacia complex (Bcc) are significant pathogens in Cystic Fibrosis (CF) patients and are resistant to a plethora of antibiotics. In this context, microorganisms from Antarctica are interesting because they produce antimicrobial compounds inhibiting the growth of other bacteria. This is particularly true for bacteria isolated from Antarctic sponges. The aim of this work was to characterize a set of Antarctic bacteria for their ability to produce new natural drugs that could be exploited in the control of infections in CF patients by Bcc bacteria. Hence, 11 bacterial strains allocated to different genera (e.g., Pseudoalteromonas, Arthrobacter and Psychrobacter) were tested for their ability to inhibit the growth of 21 Bcc strains and some other human pathogens. All these bacteria completely inhibited the growth of most, if not all, Bcc strains, suggesting a highly specific activity toward Bcc strains. Experimental evidences showed that the antimicrobial compounds are small volatile organic compounds, and are constitutively produced via an unknown pathway. The microbial volatile profile was obtained by SPME-GC-MS within the m/z interval of 40-450. Solid phase micro extraction technique affords the possibility to extract the volatile compounds in head space with a minimal sample perturbation. Principal component analysis and successive cluster discriminant analysis was applied to evaluate the relationships among the volatile organic compounds with the aim of classifying the microorganisms by their volatile profile. These data highlight the potentiality of Antarctic bacteria as novel sources of antibacterial substances to face Bcc infections in CF patients. Copyright © 2011 John Wiley & Sons, Ltd.

Association of plasma 25-hydroxyvitamin d concentrations and pathogenic oral bacteria in postmenopausal females.

PubMed

Sahli, Michelle W; Wactawski-Wende, Jean; Ram, Pavani K; LaMonte, Michael J; Hovey, Kathleen M; Genco, Robert J; Andrews, Christopher A; Millen, Amy E

2014-07-01

Previous findings of an association between 25-hydroxyvitamin D [25(OH)D] concentrations and periodontal disease may be partially explained by the antimicrobial properties of vitamin D. To the best of the authors' knowledge, no study has investigated the association between 25(OH)D and pathogenic oral bacteria, a putative cause of periodontal disease. The association between plasma 25(OH)D concentrations and pathogenic oral bacteria was examined among postmenopausal females in the Buffalo Osteoporosis and Periodontal Disease Study (1997 to 2000), an ancillary study of the Women's Health Initiative Observational Study. Subgingival plaque samples were assessed using immunofluorescence for the presence of Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia, and Campylobacter rectus. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for prevalent bacteria by quintile (Q) of 25(OH)D concentrations, adjusting for age and body mass index. Of the 855 participants, 288 (34%) had deficient/inadequate (<50 nmol/L) 25(OH)D concentrations, and 496 (58%) had at least one species of pathogenic bacteria. No significant association was found between 25(OH)D and presence of any of these bacteria (adjusted OR for high [Q5] compared to low [Q1] 25(OH)D = 0.96; 95% CI: 0.61 to 1.50; P for trend = 0.50). Inverse, although not statistically significant, associations were found between 25(OH)D and more than one species of pathogenic bacteria (adjusted OR for adequate compared to deficient/inadequate 25(OH)D = 0.85; 95% CI: 0.60 to 1.19). No association was observed between pathogenic oral bacteria and 25(OH)D concentrations in postmenopausal females. This may be attributable to the species of bacteria assessed, small effect size, or a true absence of an association.

On a Multiphase Multicomponent Model of Biofilm Growth

NASA Astrophysics Data System (ADS)

Friedman, Avner; Hu, Bei; Xue, Chuan

2014-01-01

Biofilms are formed when free-floating bacteria attach to a surface and secrete polysaccharide to form an extracellular polymeric matrix (EPS). A general model of biofilm growth needs to include the bacteria, the EPS, and the solvent within the biofilm region Ω( t), and the solvent in the surrounding region D( t). The interface between the two regions, Γ( t), is a free boundary. In this paper, we consider a mathematical model that consists of a Stokes equation for the EPS with bacteria attached to it, a Stokes equation for the solvent in Ω( t) and another for the solvent in D( t). The volume fraction of the EPS is another unknown satisfying a reaction-diffusion equation. The entire system is coupled nonlinearly within Ω( t) and across the free surface Γ( t). We prove the existence and uniqueness of a solution, with a smooth surface Γ( t), for a small time interval.

[Indirect and repeated electromagnetic irradiation of extremely high freguency of bacteria Escherichia coli].

PubMed

Isakhanian, V; Trchunian, A

2005-01-01

It has been shown that separate irradiation of distilled water and tris-phosphate buffer containing some inorganic ions, with Escherichia coli K12 grown in anaerobic conditions upon fermentation of sugar (glucose) with "noise" electromagnetic radiation of extremely high frequencies (53.5-68 gHz) or millimeter waves (wavelength of 3 to 8 mm) with low flux capacity (0.01 mW) for 10, 30 and 60 min caused opposite effects, changing the growth of these bacteria. The irradiation of water has a bactericide effect, whereas the irradiation of the buffer stimulates bacterial growth although the buffer itself inhibits the growth. These results point out the role of water in the bactericide action of "noise" electromagnetic radiation of extremely high frequencies, and confirm the significance of membranotropic effects. The bactericide action disappeared after repeated irradiation for 10 and 30 min with 2-h intervals. This indicates the operation of some compensatory mechanisms in bacteria.

Bactericidal Effects of HVOF-Sprayed Nanostructured TiO2 on Pseudomonas aeruginosa

NASA Astrophysics Data System (ADS)

Jeffery, B.; Peppler, M.; Lima, R. S.; McDonald, A.

2010-01-01

Titanium dioxide (TiO2) has been shown to exhibit photocatalytic bactericidal activity. This preliminary study focused on examining the photocatalytic activity of high-velocity oxy-fuel (HVOF) sprayed nanostructured TiO2 coatings to kill Pseudomonas aeruginosa. The surfaces of the nanostructured TiO2 coatings were lightly polished before addition of the bacterial solution. Plates of P. aeruginosa were grown, and then suspended in a phosphate buffer saline (PBS) solution. The concentration of bacteria used was determined by a photo-spectrometer, which measured the amount of light absorbed by the bacteria-filled solution. This solution was diluted and pipetted onto the coating, which was exposed to white light in 30-min intervals, up to 120 min. It was found that on polished HVOF-sprayed coatings exposed to white light, 24% of the bacteria were killed after exposure for 120 min. On stainless steel controls, approximately 6% of the bacteria were not recovered. These preliminary results show that thermal-sprayed nanostructured TiO2 coatings exhibited photocatalytic bactericidal activity with P. aeruginosa.

Reproductive Performance, Udder Health, and Antibiotic Resistance in Mastitis Bacteria isolated from Norwegian Red cows in Conventional and Organic Farming

PubMed Central

2010-01-01

Background The objectives of this study were to investigate whether there were differences between Norwegian Red cows in conventional and organic farming with respect to reproductive performance, udder health, and antibiotic resistance in udder pathogens. Methods Twenty-five conventional and 24 organic herds from south-east and middle Norway participated in the study. Herds were matched such that geographical location, herd size, and barn types were similar across the cohorts. All organic herds were certified as organic between 1997 and 2003. All herds were members of the Norwegian Dairy Herd Recording System. The herds were visited once during the study. The relationship between the outcomes and explanatory variables were assessed using mixed linear models. Results There were less > 2nd parity cows in conventional farming. The conventional cows had higher milk yields and received more concentrates than organic cows. Although after adjustment for milk yield and parity, somatic cell count was lower in organic cows than conventional cows. There was a higher proportion of quarters that were dried off at the herd visit in organic herds. No differences in the interval to first AI, interval to last AI or calving interval was revealed between organic and conventional cows. There was no difference between conventional and organic cows in quarter samples positive for mastitis bacteria from the herd visit. Milk yield and parity were associated with the likelihood of at least one quarter positive for mastitis bacteria. There was few S. aureus isolates resistance to penicillin in both management systems. Penicillin resistance against Coagulase negative staphylococci isolated from subclinically infected quarters was 48.5% in conventional herds and 46.5% in organic herds. Conclusion There were no large differences between reproductive performance and udder health between conventional and organic farming for Norwegian Red cows. PMID:20141638

A multiscale model on hospital infections coupling macro and micro dynamics

NASA Astrophysics Data System (ADS)

Wang, Xia; Tang, Sanyi

2017-09-01

A multiscale model of hospital infections coupling the micro model of the growth of bacteria and the macro model describing the transmission of the bacteria among patients and health care workers (HCWs) was established to investigate the effects of antibiotic treatment on the transmission of the bacteria among patients and HCWs. The model was formulated by viewing the transmission rate from infected patients to HCWs and the shedding rate of bacteria from infected patients to the environment as saturated functions of the within-host bacterial load. The equilibria and the basic reproduction number of the coupled system were studied, and the global dynamics of the disease free equilibrium and the endemic equilibrium were analyzed in detail by constructing two Lyapunov functions. Furthermore, effects of drug treatment in the within-host model on the basic reproduction number and the dynamics of the coupled model were studied by coupling a pharmacokinetics model with the within-host model. Sensitive analysis indicated that the growth rate of the bacteria, the maximum drug effect and the dosing interval are the three most sensitive parameters contributing to the basic reproduction number. Thus, adopting ;wonder; drugs to decrease the growth rate of the bacteria or to increase the drug's effect is the most effective measure but changing the dosage regime is also effective. A quantitative criterion of how to choose the best dosage regimen can also be obtained from numerical results.

Protist-facilitated transport of soil bacteria in an artificial soil micromodel

NASA Astrophysics Data System (ADS)

Rubinstein, R. L.; Cousens, V.; Gage, D. J.; Shor, L. M.

2013-12-01

Soil bacteria within the rhizosphere benefit plants by protecting roots from pathogens, producing growth factors, and improving nutrient availability. These effects can greatly improve overall plant health and increase crop yield, but as roots grow out from the tips they quickly outpace their bacterial partners. Some soil bacteria are motile and can chemotact towards root tips, but bacterial mobility in unsaturated soils is limited to interconnected hydrated pores. Mobility is further reduced by the tendency of soil bacteria to form biofilms. The introduction of protists to the rhizosphere has been shown to benefit plants, purportedly by selective grazing on harmful bacteria or release of nutrients otherwise sequestered in bacteria. We propose that an additional benefit to the presence of protists is the facilitated transport of beneficial bacteria along root systems. Using microfluidic devices designed to imitate narrow, fluid-filled channels in soil, we have shown that the distribution of bacteria through micro-channels is accelerated in the presence of protists. Furthermore, we have observed that even with predation effects, the bacteria remain viable and continue to reproduce for the duration of our experiments. These results expand upon our understanding of complex bio-physical interactions in the rhizosphere system, and may have important implications for agricultural practices.

Chemical modification of capuramycins to enhance antibacterial activity

PubMed Central

Bogatcheva, Elena; Dubuisson, Tia; Protopopova, Marina; Einck, Leo; Nacy, Carol A.; Reddy, Venkata M.

2011-01-01

Objectives To extend capuramycin spectrum of activity beyond mycobacteria and improve intracellular drug activity. Methods Three capuramycin analogues (SQ997, SQ922 and SQ641) were conjugated with different natural and unnatural amino acids or decanoic acid (DEC) through an ester bond at one or more available hydroxyl groups. In vitro activity of the modified compounds was determined against Mycobacterium spp. and representative Gram-positive and Gram-negative bacteria. Intracellular activity was evaluated in J774A.1 mouse macrophages infected with Mycobacterium tuberculosis (H37Rv). Results Acylation of SQ997 and SQ641 with amino undecanoic acid (AUA) improved in vitro activity against most of the bacteria tested. Conjugation of SQ922 with DEC, but not AUA, improved its activity against Gram-positive bacteria. In the presence of efflux pump inhibitor phenylalanine arginine β-naphthyl amide, MICs of SQ997-AUA, SQ641-AUA and SQ922-DEC compounds improved even further against drug-susceptible and drug-resistant Staphylococcus aureus. In Gram-negative bacteria, EDTA-mediated permeabilization caused 4- to 16-fold enhancement of the activity of AUA-conjugated SQ997, SQ922 and SQ641. Conjugation of all three capuramycin analogues with AUA improved intracellular killing of H37Rv in murine macrophages. Conclusions Conjugation of capuramycin analogues with AUA or DEC enhanced in vitro activity, extended the spectrum of activity in Gram-positive bacteria and increased intracellular activity against H37Rv. PMID:21186194

Some bacteria are beneficial!

USGS Publications Warehouse

McMahon, Peter B.

1995-01-01

Most people would agree that bacteria usually spell trouble where the quality of drinking water is con cerned. However, recent studies conducted by the U.S. Geological Survey (USGS) under the National Water-Quality Assessment (NAWQA) program have shown that some bacteria can improve the quality of water.

IMPACT OF SOIL MANAGEMENT ON COTTON RHIZOSPHERE BACTERIA

USDA-ARS?s Scientific Manuscript database

Soil dwelling bacteria and fungi are responsible for a number of ecosystem services critical to agriculture. In particular, bacteria living in the rhizosphere (portion of soil directly influenced by plant roots) and arbuscular mycorrhizal fungi have been shown to improve nutrient and water uptake an...

Biochanin A improves fiber fermentation by cellulolytic bacteria

USDA-ARS?s Scientific Manuscript database

The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity. When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39 °C) with ground hay, cellulolytic bacteria proliferated, short chain fatty...

Enzymatic Digestion for Improved Bacteria Separation from Leafy Green Vegetables.

PubMed

Wang, Danhui; Wang, Ziyuan; He, Fei; Kinchla, Amanda J; Nugen, Sam R

2016-08-01

An effective and rapid method for the separation of bacteria from food matrix remains a bottleneck for rapid bacteria detection for food safety. Bacteria can strongly attach to a food surface or internalize within the matrix, making their isolation extremely difficult. Traditional methods of separating bacteria from food routinely involve stomaching, blending, and shaking. However, these methods may not be efficient at removing all the bacteria from complex matrices. Here, we investigate the benefits of using enzyme digestion followed by immunomagnetic separation to isolate Salmonella from spinach and lettuce. Enzymatic digestion using pectinase and cellulase was able to break down the structure of the leafy green vegetables, resulting in the detachment and release of Salmonella from the leaves. Immunomagnetic separation of Salmonella from the liquefied sample allowed an additional separation step to achieve a more pure sample without leaf debris that may benefit additional downstream applications. We have investigated the optimal combination of pectinase and cellulase for the digestion of spinach and lettuce to improve sample detection yields. The concentrations of enzymes used to digest the leaves were confirmed to have no significant effect on the viability of the inoculated Salmonella. Results reported that the recovery of the Salmonella from the produce after enzyme digestion of the leaves was significantly higher (P < 0.05) than traditional sample preparation methods to separate bacteria (stomaching and manually shaking). The results demonstrate the potential for use of enzyme digestion prior to separation can improve the efficiency of bacteria separation and increase the likelihood of detecting pathogens in the final detection assay.

Improvement of the trace metal composition of medium for nitrite-dependent anaerobic methane oxidation bacteria: Iron (II) and copper (II) make a difference.

PubMed

He, Zhanfei; Geng, Sha; Pan, Yawei; Cai, Chaoyang; Wang, Jiaqi; Wang, Liqiao; Liu, Shuai; Zheng, Ping; Xu, Xinhua; Hu, Baolan

2015-11-15

Nitrite-dependent anaerobic methane oxidation (n-damo) is a potential bioprocess for treating nitrogen-containing wastewater. This process uses methane, an inexpensive and nontoxic end-product of anaerobic digestion, as an external electron donor. However, the low turnover rate and slow growth rate of n-damo functional bacteria limit the practical application of this process. In the present study, the short- and long-term effects of variations in trace metal concentrations on n-damo bacteria were investigated, and the concentrations of trace metal elements of medium were improved. The results were subsequently verified by a group of long-term inoculations (90 days) and were applied in a sequencing batch reactor (SBR) (84 days). The results indicated that iron (Fe(II)) and copper (Cu(II)) (20 and 10 μmol L(-1), respectively) significantly stimulated the activity and the growth of n-damo bacteria, whereas other trace metal elements, including zinc (Zn), molybdenum (Mo), cobalt (Co), manganese (Mn), and nickel (Ni), had no significant effect on n-damo bacteria in the tested concentration ranges. Interestingly, fluorescence in situ hybridization (FISH) showed that a large number of dense, large aggregates (10-50 μm) of n-damo bacteria were formed by cell adhesion in the SBR reactor after using the improved medium, and to our knowledge this is the first discovery of large aggregates of n-damo bacteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nutrient Loading Impacts on Culturable E. coli and other Heterotrophic Bacteria Fate in Simulated Stream Mesocosms

USDA-ARS?s Scientific Manuscript database

Understanding fecal indicator bacteria persistence in aquatic environments is important when making management decisions to improve instream water quality. Routinely, bacteria fate and transport models that rely on published kinetic decay constants are used to inform such decision making. The object...

[Current epidemiology of microbial low respiratory tract infections].

PubMed

Trémolières, F

2006-01-01

The recent literature brings nothing new since it provides only fragmented, though undoubtedly useful, studies which remain within the prevalence interval for the different bacterias. The occurrence of germs varies with time and space; nevertheless, whatever the studied series and the site of the studies, the 3 most frequent causal germs belong to the following five strains: Streptococcus pneumoniae, Influenza A, Mycoplasma pneumoniae, Haemophilus influenzae, and Legionella pneumophila. Thus, 90% of all documented pneumoniae appear to be caused by the following pathogens: Pneumococcus; most frequent in hospitalized patients; Mycoplasma, Chlamydia and respiratory viruses were predominant in outpatients, with great variations; Staphylococcus and enterobacteriace may be encountered, mostly in elderlies with major debilitating diseases; association of germs, generally including pneumococcus, are increasingly identified. Last, in 25% to 50% of cases, the causal agent is not known. Recently, some Staphylococcus meticillin-resistant were identified. The diagnosis of viruses (as well as that of atypical bacterias) seems to have improved, thanks to the use of PCR though the interest of such a diagnosis remains questionable, except for epidemiological studies, as well as the relevance of this type of test in clinical practice. Nothing really new has come out on the epidemiology of acute bronchitis, while in bacterial exacerbation of COPD, attention focused on the colonizing or infective role of H. influenzae in the genesis of bronchus inflammation.

Antibacterial activation of hydroxyapatite (HA) with controlled porosity by different antibiotics.

PubMed

Chai, F; Hornez, J-C; Blanchemain, N; Neut, C; Descamps, M; Hildebrand, H F

2007-11-01

In order to prevent the increasing frequency of per-operative infections, bioceramics can be loaded with anti-bacterial agents, which will release with respect to their chemical characteristics. A novel hydroxyapatite (HA) was elaborated with specific internal porosities for using as a bone-bioactive antibiotic (ATB) carrier material. UV spectrophotometry and bacteria inhibition tests were performed for testing the ATB adsorption and the microbiological effectiveness after loading with different antibiotics. The impregnation time, ATB impregnating concentration, impregnation condition and other factors, which might influence the ATB loading effect, were studied by exposure to different releasing solvents and different pathogenic bacteria: Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. It clearly showed that the facility of ATB loading on this porous HA is even possible just under simple non-vacuum impregnation conditions in a not-so-long impregnating interval. The results also showed that, for all three types of ATB (vancomycin, ciprofloxacin and gentamicin), adsorbed amount on the micro-porous HA were hugely higher than that on dense HA. The micro-porosity of test HA had also significantly prolonged the release time of antibiotics even under mimic physiological conditions. Furthermore, it also has primarily proved by a pilot test that the antibacterial efficiency of crude micro-porous HA could be further significantly improved by other methods of functionalization such as cold plasma technique.

Biochemical Engineering Approaches for Increasing Viability and Functionality of Probiotic Bacteria

PubMed Central

Nguyen, Huu-Thanh; Truong, Dieu-Hien; Kouhoundé, Sonagnon; Ly, Sokny; Razafindralambo, Hary; Delvigne, Frank

2016-01-01

The literature presents a growing body of evidence demonstrating the positive effect of probiotics on health. Probiotic consumption levels are rising quickly in the world despite the fluctuation of their viability and functionality. Technological methods aiming at improving probiotic characteristics are thus highly wanted. However, microbial metabolic engineering toolbox is not available for this kind of application. On the other hand, basic microbiology teaches us that bacteria are able to exhibit adaptation to external stresses. It is known that adequately applied sub-lethal stress, i.e., controlled in amplitude and frequency at a given stage of the culture, is able to enhance microbial robustness. This property could be potentially used to improve the viability of probiotic bacteria, but some technical challenges still need to be overcome before any industrial implementation. This review paper investigates the different technical tools that can be used in order to define the proper condition for improving viability of probiotic bacteria and their implementation at the industrial scale. Based on the example of Bifidobacterium bifidum, potentialities for simultaneously improving viability, but also functionality of probiotics will be described. PMID:27271598

Quantitative Real-time Polymerase Chain Reaction for Enteropathogenic Escherichia coli: A Tool for Investigation of Asymptomatic Versus Symptomatic Infections

PubMed Central

Barletta, Francesca; Mercado, Erik; Ruiz, Joaquim; Ecker, Lucie; Lopez, Giovanni; Mispireta, Monica; Gil, Ana I.; Lanata, Claudio F.; Cleary, Thomas G.

2011-01-01

Background. Enteropathogenic Escherichia coli (EPEC) strains are pediatric pathogens commonly isolated from both healthy and sick children with diarrhea in areas of endemicity. The aim of this study was to compare the bacterial load of EPEC isolated from stool samples from children with and without diarrhea to determine whether bacterial load might be a useful tool for further study of this phenomenon. Methods. EPEC was detected by polymerase chain reaction (PCR) of colonies isolated on MacConkey plates from 53 diarrheal and 90 healthy children aged <2 years. DNA was isolated from stool samples by cetyltrimethylammonium bromide extraction. To standardize quantification by quantitative real-time PCR (qRT-PCR), the correlation between fluorescence threshold cycle and copy number of the intimin gene of EPEC E2348/69 was determined. Results. The detection limit of qRT-PCR was 5 bacteria/mg stool. The geometric mean load in diarrhea was 299 bacteria/mg (95% confidence interval [CI], 77–1164 bacteria/mg), compared with 29 bacteria/mg (95% CI, 10–87 bacteria/mg) in control subjects (P = .016). Bacterial load was significantly higher in children with diarrhea than in control subjects among children <12 months of age (178 vs 5 bacteria/mg; P = .006) and among children with EPEC as the sole pathogen (463 vs 24 bacteria/mg; P = .006). Conclusions. EPEC load measured by qRT-PCR is higher in diarrheal than in healthy children. qRT-PCR may be useful to study the relationship between disease and colonization in settings of endemicity. PMID:22028433

Quantitative and Qualitative Study of Intestinal Flora in Neonates

PubMed Central

Sharma, Nidhi; Chaudhry, Rama; Panigrahi, Pinaki

2012-01-01

Background: In the neonatal period the developing intestinal barrier function provides a sub-optimal mucosal defense against infection. Establishment of the normal commensal micro-flora plays a vital role in this process. Aims: To determine aerobic and anaerobic bacteria by quantitative and qualitative methods from faecal samples of neonates. Settings and Design: A prospective study was carried out in two groups in a tertiary care hospital, Group A-comprised preterm infant and in group B-full term infants. Materials and Methods: Sixty two preterm infants with the weight < 1500 gm and gestation age < 34 weeks and twenty nine full term infants with 4 weeks of age were included. Quantitation of bacterial load was done by ten-fold serial dilutions on respective media. Statistical Analysis: The data were analyzed by using EPIINFO-Ver 6.04. Results and Conclusions: The predominant aerobic bacterium was Klebsiella pneumoniae. In pre term infants aerobic bacteria were colonized with an average of 2.1 and anaerobic bacteria 0.1. Quantitation showed faecal bacterial colony count ranging from 104-1013 CFU/gms. Gram negative and gram positive bacteria increased gradually over an interval of 2 to 3 weeks. Mean log CFU of gram negative bacteria and gram positive bacteria were statistically insignificant from day 3 to day 14 (P > 0.05). On day 21 there was a significant change in colonization of both bacterial sp (P < 0.05). Potential pathogenic aerobic bacteria dominate the intestinal flora of premature babies nursed in neonatal unit. There is a need to investigate interventions to offset this imbalance in gut micro-ecology of premature babies. PMID:23326075

The study of formulated Zoush ointment against wound infection and gene expression of virulence factors Pseudomonas aeruginosa.

PubMed

Meskini, Maryam; Esmaeili, Davoud

2018-06-15

The outbreak of MDR and XDR strains of Pseudomonas aeruginosa and increased resistance to infection in burn patients recommend the issue of infection control. In this research, we study ZOUSH herbal ointment for gene silencing of Pseudomonas aeruginosa. The herbal ZOUSH ointment was formulated by alcoholic extracts of plants Satureja khuzestaniea, Zataria multiflora, Mentha Mozaffariani Jamzad, honey, and polyurethane. The MIC and disk diffusion tests were examined by single, binary, tertiary and five compounds. Three-week-old mice were considered to be second-degree infections by Pseudomonas aeruginosa. During the interval of 5 days, cultures were done from the liver, blood, and wound by four consecutive quarters and counting of Pseudomonas aeruginosa was reported in the liver. In this study, silver sulfadiazine ointments and Akbar were used as a positive control. The gene gyrA reference was used as the control. Real-time RT-PCR results were evaluated based on Livak as the comparative Ct method. The In vitro results indicated that wound infection was improved by healing wound size in the treatment groups compared to control treatment group. In this research, the changes in gene expression were evaluated by molecular technique Real-time RT-PCR. The results showed downregulation exoS, lasA, and lasB after treatment with ZOUSH ointment. SPSS Analyses showed that reduction of expressions in genes exoS, lasA and lasB after treatment with ZOUSH ointment were significantly meaningful (p < 0.05). Our study showed that ZOUSH ointment has the positive effect for gene silencing Pseudomonas aeruginosa in the mouse model with the second-degree burn. The positive effects decreased in the number of bacteria by reducing the expression of virulence bacteria genes as exoS, lasA and lasB and improvement of wound healing.

EFFECT OF SITE ON BACTERIAL POPULATIONS IN THE SAPWOOD OF COARSE WOODY DEBRIS.

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

Porter, Emma, G.,; Waldrop, Thomas, A.; McElreath, Susan, D.

1998-01-01

Porter, Emma G., T.A. Waldrop, Susan D. McElreath, and Frank H. Tainter. 1998. Effect of site on bacterial populations in the sapwood of coarse woody debris. Pp. 480-484. In: Proc. 9th Bienn. South. Silv. Res. Conf. T.A. Waldrop (ed). USDA Forest Service, Southern Research Station. Gen. Tech. Rep. SRS-20. Abstract: Coarse woody debris (CWD) is an important structural component of southeastern forest ecosystems, yet little is known about its dynamics in these systems. This project identified bacterial populations associated with CWD and their dynamics across landscape ecosystem classification (LEC) units. Bolts of red oak and loblolly pine were placed onmore » plots at each of three hydric, mesic, and xeric sites at the Savannah River Station. After the controls were processed, samples were taken at four intervals over a 16-week period. Samples were ground within an anaerobe chamber using nonselective media. Aerobic and facultative anaerobic bacteria were identified using the Biolog system and the anaerobes were identified using the API 20A system. Major genera isolated were: Bacillus, Buttiauxella, Cedecea, Enterobacter, Erwinia, Escherichia, Klebsiella, Pantoea, Pseudomonas, Serratia, and Xanthomonas. The mean total isolates were determined by LEC units and sample intervals. Differences occurred between the sample intervals with total isolates of 6.67, 13.33, 10.17, and 9.50 at 3, 6, 10, and 16 weeks, respectively. No significant differences in the numbers of bacteria isolated were found between LEC units.« less

Deployable micro-traps to sequester motile bacteria

NASA Astrophysics Data System (ADS)

di Giacomo, Raffaele; Krödel, Sebastian; Maresca, Bruno; Benzoni, Patrizia; Rusconi, Roberto; Stocker, Roman; Daraio, Chiara

2017-04-01

The development of strategies to reduce the load of unwanted bacteria is a fundamental challenge in industrial processing, environmental sciences and medical applications. Here, we report a new method to sequester motile bacteria from a liquid, based on passive, deployable micro-traps that confine bacteria using micro-funnels that open into trapping chambers. Even in low concentrations, micro-traps afford a 70% reduction in the amount of bacteria in a liquid sample, with a potential to reach >90% as shown by modelling improved geometries. This work introduces a new approach to contain the growth of bacteria without chemical means, an advantage of particular importance given the alarming growth of pan-drug-resistant bacteria.

Deployable micro-traps to sequester motile bacteria

PubMed Central

Di Giacomo, Raffaele; Krödel, Sebastian; Maresca, Bruno; Benzoni, Patrizia; Rusconi, Roberto; Stocker, Roman; Daraio, Chiara

2017-01-01

The development of strategies to reduce the load of unwanted bacteria is a fundamental challenge in industrial processing, environmental sciences and medical applications. Here, we report a new method to sequester motile bacteria from a liquid, based on passive, deployable micro-traps that confine bacteria using micro-funnels that open into trapping chambers. Even in low concentrations, micro-traps afford a 70% reduction in the amount of bacteria in a liquid sample, with a potential to reach >90% as shown by modelling improved geometries. This work introduces a new approach to contain the growth of bacteria without chemical means, an advantage of particular importance given the alarming growth of pan-drug-resistant bacteria. PMID:28378786

Deployable micro-traps to sequester motile bacteria.

PubMed

Di Giacomo, Raffaele; Krödel, Sebastian; Maresca, Bruno; Benzoni, Patrizia; Rusconi, Roberto; Stocker, Roman; Daraio, Chiara

2017-04-05

The development of strategies to reduce the load of unwanted bacteria is a fundamental challenge in industrial processing, environmental sciences and medical applications. Here, we report a new method to sequester motile bacteria from a liquid, based on passive, deployable micro-traps that confine bacteria using micro-funnels that open into trapping chambers. Even in low concentrations, micro-traps afford a 70% reduction in the amount of bacteria in a liquid sample, with a potential to reach >90% as shown by modelling improved geometries. This work introduces a new approach to contain the growth of bacteria without chemical means, an advantage of particular importance given the alarming growth of pan-drug-resistant bacteria.

Micro-scale experimental study of Microbial-Induced Carbonate Precipitation (MICP) by using microfluidic devices

NASA Astrophysics Data System (ADS)

Wang, Y.; Soga, K.; DeJong, J. T.; Kabla, A.

2017-12-01

Microbial-induced carbonate precipitation (MICP), one of the bio-mineralization processes, is an innovative subsurface improvement technique for enhancing the strength and stiffness of soils, and controlling their hydraulic conductivity. These macro-scale engineering properties of MICP treated soils controlled by micro-scale factors of the precipitated carbonate, such as its content, amount and distribution in the soil matrix. The precipitation process itself is affected by bacteria amount, reaction kinetics, porous medium geometry and flow distribution in the soils. Accordingly, to better understand the MICP process at the pore scale a new experimental technique that can observe the entire process of MICP at the pore-scale was developed. In this study, a 2-D transparent microfluidic chip made of Polydimethylsiloxane (PDMS) representing the soil matrix was designed and fabricated. A staged-injection MICP treatment procedure was simulated inside the microfluidic chip while continuously monitored using microscopic techniques. The staged-injection MICP treatment procedure started with the injection of bacteria suspension, followed with the bacteria setting for attachment, and then ended with the multiple injections of cementation liquid. The main MICP processes visualized during this procedure included the bacteria transport and attachment during the bacteria injection, the bacteria attachment and growth during the bacteria settling, the bacteria detachment during the cementation liquid injection, the cementation development during the cementation liquid injection, and the cementation development after the completion of cementation liquid injection. It is suggested that the visualization of the main MICP processes using the microfluidic technique can improve understating of the fundamental mechanisms of MICP and consequently help improve the treatment technique for in situ implementation of MICP.

Surveillance of multidrug resistant uropathogenic bacteria in hospitalized patients in Indian

PubMed Central

Mishra, Monali Priyadarsini; Debata, Nagen Kumar; Padhy, Rabindra Nath

2013-01-01

Objective To record surveillance, antibiotic resistance of uropathogens of hospitalized patients over a period of 18 months. Methods Urine samples from wards and cabins were used for isolating urinary tract infection (UTI)-causing bacteria that were cultured on suitable selective media and identified by biochemical tests; and their antibiograms were ascertained by Kirby-Bauer's disc diffusion method, in each 6-month interval of the study period, using 18 antibiotics of five different classes. Results From wards and cabins, 1 245 samples were collected, from which 996 strains of bacteria belonging to 11 species were isolated, during April 2011 to September 2012. Two Gram-positive, Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), and nine Gram-negative bacteria, Acinetobacter baumannii, Citrobacter sp., Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis, Proteus vulgaris and Pseudomonas aeruginosa were isolated. Both S. aureus and E. faecalis were vancomycin resistant, and resistant-strains of all pathogens increased in each 6-month period of study. Particularly, all Gram-negatives were resistant to nitrofurantoin and co-trimoxazole, the most preferred antibiotics of empiric therapy for UTI. Conclusions Antibiograms of 11 UTI-causing bacteria recorded in this study indicated moderately higher numbers of strains resistant to each antibiotic studied, generating the fear of precipitating fervent episodes in public health particularly with bacteria, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and S. aureus. Moreover, vancomycin resistance in strains of S. aureus and E. faecalis is a matter of concern. PMID:23620859

Inner Plant Values: Diversity, Colonization and Benefits from Endophytic Bacteria

PubMed Central

Liu, Hongwei; Carvalhais, Lilia C.; Crawford, Mark; Singh, Eugenie; Dennis, Paul G.; Pieterse, Corné M. J.; Schenk, Peer M.

2017-01-01

One of the most exciting scientific advances in recent decades has been the realization that the diverse and immensely active microbial communities are not only ‘passengers’ with plants, but instead play an important role in plant growth, development and resistance to biotic and abiotic stresses. A picture is emerging where plant roots act as ‘gatekeepers’ to screen soil bacteria from the rhizosphere and rhizoplane. This typically results in root endophytic microbiome dominated by Proteobacteria, Actinobacteria and to a lesser extent Bacteroidetes and Firmicutes, but Acidobacteria and Gemmatimonadetes being almost depleted. A synthesis of available data suggest that motility, plant cell-wall degradation ability and reactive oxygen species scavenging seem to be crucial traits for successful endophytic colonization and establishment of bacteria. Recent studies provide solid evidence that these bacteria serve host functions such as improving of plant nutrients through acquisition of nutrients from soil and nitrogen fixation in leaves. Additionally, some endophytes can engage ‘priming’ plants which elicit a faster and stronger plant defense once pathogens attack. Due to these plant growth-promoting effects, endophytic bacteria are being widely explored for their use in the improvement of crop performance. Updating the insights into the mechanism of endophytic bacterial colonization and interactions with plants is an important step in potentially manipulating endophytic bacteria/microbiome for viable strategies to improve agricultural production. PMID:29312235

Eggshell bacterial levels of non-washed and washed eggs from caged and cage-free hens

USDA-ARS?s Scientific Manuscript database

The bacteria levels of non-washed and washed eggs obtained from caged and cage-free laying hens housed on either all shavings or all wire slat floors were determined. On eight sample days (from 22 to 52 weeks at 4 week intervals), 20 eggs were collected from each pen (n=120/sample day). Ten eggs p...

Continuous Microfluidics (Ecology-on-a-Chip) Experiments for Long Term Observation of Bacteria at Liquid-Liquid Interfaces

NASA Astrophysics Data System (ADS)

Miranda, Michael; White, Andrew; Jalali, Maryam; Sheng, Jian

2017-11-01

A microfluidic bioassay incorporating a peristaltic pump and chemostat capable of continuously culturing a bacterial suspension through a microchannel for an extended period of time relevant to ecological processes is presented. A single crude oil droplet is dispensed on-chip and subsequently pinned to the top and bottom surfaces of the microchannel to establish a vertical curved oil-water interface to observe bacteria without boundary interference. The accumulation of extracellular polymeric substances (EPS), microbial film formation, and aggregation is provided by DIC microscopy with an EMCCD camera at an interval of 30 sec. Cell-interface interactions such as cell translational and angular motilities as well as encountering, attachment, detachment to the interface are obtained by a high speed camera at 1000 fps with a sampling interval of 10 min. Experiments on Pseudomonas sp. (P62) and isolated EPS suspensions from Sagitulla Stelleta and Roseobacter show rapid formation of bacterial aggregates including EPS streamers stretching tens of drop diameters long. These results provide crucial insights into environmentally relevant processes such as the initiation of marine oil snow, an alternative mode of biodegradation to conventional bioconsumption. Funded by GoMRI, NSF, ARO.

Ratio-based lengths of intervals to improve fuzzy time series forecasting.

PubMed

Huarng, Kunhuang; Yu, Tiffany Hui-Kuang

2006-04-01

The objective of this study is to explore ways of determining the useful lengths of intervals in fuzzy time series. It is suggested that ratios, instead of equal lengths of intervals, can more properly represent the intervals among observations. Ratio-based lengths of intervals are, therefore, proposed to improve fuzzy time series forecasting. Algebraic growth data, such as enrollments and the stock index, and exponential growth data, such as inventory demand, are chosen as the forecasting targets, before forecasting based on the various lengths of intervals is performed. Furthermore, sensitivity analyses are also carried out for various percentiles. The ratio-based lengths of intervals are found to outperform the effective lengths of intervals, as well as the arbitrary ones in regard to the different statistical measures. The empirical analysis suggests that the ratio-based lengths of intervals can also be used to improve fuzzy time series forecasting.

Effect of clindamycin prophylaxis on the colonic microflora in patients undergoing colorectal surgery.

PubMed Central

Kager, L; Liljeqvist, L; Malmborg, A S; Nord, C E

1981-01-01

Clindamycin was given intravenously to 15 patients undergoing colorectal surgery in an initial dose of 600 mg, given at induction of anesthesia followed by 6 doses of 600 mg at 8-h intervals. Series of serum samples and fecal specimens were taken for analysis of clindamycin concentrations. Tissue samples from the gut wall were taken at surgery. The highest serum concentrations observed occurred 30 min after administration of clindamycin and varied between 6.8 and 37.9 microgram/ml (mean, 14.8 +/- 2.0 [standard error] microgram/ml). The clindamycin concentrations in the tissue samples were between 1.8 and 13.0 microgram/g. Clindamycin concentration in the fecal samples varied between 2.1 and 460 microgram/g. Fecal samples were also collected during the investigation period for cultivation of aerobic and anaerobic bacteria. Among the aerobic bacteria, enterococci and streptococci decreased during the prophylaxis period. Anaerobic bacteria also decreased significantly during the same period. After the clindamycin administration period, enterococci, streptococci and anaerobic bacteria proliferated. No anaerobic strains resistant to clindamycin were isolated. Postoperative infections due to Streptococcus faecalis and different enterobacteria such as Escherichia coli, Enterobacter cloacae, Citrobacter freundii, and Klebsiella occurred in five patients. PMID:7325640

Effect of clindamycin prophylaxis on the colonic microflora in patients undergoing colorectal surgery.

PubMed

Kager, L; Liljeqvist, L; Malmborg, A S; Nord, C E

1981-12-01

Clindamycin was given intravenously to 15 patients undergoing colorectal surgery in an initial dose of 600 mg, given at induction of anesthesia followed by 6 doses of 600 mg at 8-h intervals. Series of serum samples and fecal specimens were taken for analysis of clindamycin concentrations. Tissue samples from the gut wall were taken at surgery. The highest serum concentrations observed occurred 30 min after administration of clindamycin and varied between 6.8 and 37.9 microgram/ml (mean, 14.8 +/- 2.0 [standard error] microgram/ml). The clindamycin concentrations in the tissue samples were between 1.8 and 13.0 microgram/g. Clindamycin concentration in the fecal samples varied between 2.1 and 460 microgram/g. Fecal samples were also collected during the investigation period for cultivation of aerobic and anaerobic bacteria. Among the aerobic bacteria, enterococci and streptococci decreased during the prophylaxis period. Anaerobic bacteria also decreased significantly during the same period. After the clindamycin administration period, enterococci, streptococci and anaerobic bacteria proliferated. No anaerobic strains resistant to clindamycin were isolated. Postoperative infections due to Streptococcus faecalis and different enterobacteria such as Escherichia coli, Enterobacter cloacae, Citrobacter freundii, and Klebsiella occurred in five patients.

Temperature and pH effect on glucose production from pretreated bagasse by a novel species of Citrobacter and other bacteria.

PubMed

Jones, Jamila A D; Kerr, R G; Haltli, B A; Tinto, Winston F

2018-06-01

Cellulolytic bacteria that produce cellulases, which are active over a range of pH and temperatures, can be used to catalyze hydrolysis of pretreated lignocellulosic material. This is important in the production of second generation biofuels among other biotechnological applications. In this investigation, bacteria isolated from sugarcane bagasse were identified as strains of Enterobacter xiangfangensis , Serratia rubidaea , Klebsiella pneumoniae and a novel species of Citrobacter designated Citrobacter sp. UWIBGS10. The glucose production potential of these strains was studied on thermally and solvent pretreated sugarcane bagasse. This was performed at 24-hour intervals up to 168 hours in the range of pH 5-9 and temperature range 25-40 °C. Maximal concentrations of glucose for Citrobacter sp. UWIBGS10 occurred at pH 6 and 25 °C. For E. xiangfangensis , S. rubidaea , K. pneumoniae glucose concentrations were consistent across the pH and temperature ranges examined. From these results it could be concluded that the bacteria demonstrated ability for lignocellulolytic hydrolysis for the production of glucose and could be further explored for the characterization of commercial cellulolytic enzymes.

Potential nitrification in alum-treated soil slurries amended with poultry manure.

PubMed

Gandhapudi, S K; Coyne, M S; D'Angelo, E M; Matocha, C

2006-03-01

Alum is used to reduce environmental pollutants in poultry production. Alum decreases NH3 volatilization and increases total N and NH4+-N compared to untreated poultry manure. Nitrification in poultry wastes could therefore be stimulated due to higher NH4+ concentrations or could be inhibited because the soil environment is acidified. A 10-day laboratory study was conducted to study potential nitrification rates in soil slurries (20 g soil in 150 ml water) amended with 2.0 g alum-treated poultry manure. Fecal bacteria, NH4+, NO2-, NO3-, orthophosphate, pH, and NH3 were measured at 2-day intervals. Alum significantly reduced fecal bacteria concentrations through day 6. Water-soluble P was reduced 82% by day 10. Alum-treated manure had significantly increased NH4+ concentrations by day 8 and 10, and significantly decreased NO2- and NO3- concentrations by days 6-10. Alum's effect on potential nitrification was inhibitory in the soil environment. Slurries with alum-treated poultry manure had reduced nitrification rates, fecal bacteria, and soluble P. Therefore, in addition to reducing P loss, alum could temporarily reduce the risk for environmental pollution from land-applied manures in terms of both NO3- and fecal bacteria loss.

Enhanced bacterial affinity of PVDF membrane: its application as improved sea water sampling tool for environmental monitoring.

PubMed

Kumar, Sweta Binod; Sharnagat, Preeti; Manna, Paramita; Bhattacharya, Amit; Haldar, Soumya

2017-02-01

Isolation of diversified bacteria from seawater is a major challenge in the field of environmental microbiology. In the present study, an attempt has been made to select specific membrane with improved property of attaching diversified bacteria. Initially, different concentrations (15, 18, and 20% W/W) of polysulfone (PSF) were used to check their affinity for the attachment of selected gram-positive (Bacillus subtilis) and gram-negative (Escherichia coli) bacteria. Among these, 20% W/W PSF showed maximum attachment. Therefore, membrane prepared with other materials such as polyvinylidene fluoride (PVDF) and polyether sulfone (PES) were used with the same concentration (20% W/W) to check their improved bacterial attachment property. Comparative study of bacterial attachment on three different membranes revealed that PVDF possessed the highest affinity towards both the groups of bacteria. This property was confirmed by different analytical methods viz. contact angle, atomic force microscopy, zeta potential, and flux study and further validated with seawater samples collected from seven sites of western coast and Lakshadweep island of India, using Biolog EcoPlate™. All the samples showed that bacterial richness and diversity was high in PVDF membrane in comparison to surrounding seawater samples. Interestingly, affinity for more diversified bacteria was reported to be higher in water sample with less turbidity and low bacteria load. This finding can facilitate the development of PVDF (20% W/W) membrane as a simple, cheap, and less labor intensive environmental sampling tool for the isolation of diversified bacteria from seawater sample wih different physiochemical properties. Graphical abstract ᅟ.

Polymicrobial Amniotic Fluid Infection with Mycoplasma/Ureaplasma and Other Bacteria Induces Severe Intra-Amniotic Inflammation Associated with Poor Perinatal Prognosis in Preterm Labor.

PubMed

Yoneda, Noriko; Yoneda, Satoshi; Niimi, Hideki; Ueno, Tomohiro; Hayashi, Shirou; Ito, Mika; Shiozaki, Arihiro; Urushiyama, Daichi; Hata, Kenichiro; Suda, Wataru; Hattori, Masahira; Kigawa, Mika; Kitajima, Isao; Saito, Shigeru

2016-02-01

To study the relationship between perinatal prognosis in cases of preterm labor (PTL) and polymicrobial infection in amniotic fluid (AF) and intra-amniotic (IA) inflammation using a highly sensitive and reliable PCR-based method. To detect prokaryotes using a nested PCR-based method, eukaryote-made thermostable DNA polymerase without bacterial DNA contamination was used in combination with bacterial universal primers. We collected AF aseptically from 118 PTL cases and 50 term subjects. The prevalence of microorganisms was 33% (39/118) by PCR and only 7.6% (9/118) by culture. PTL caused by a combination of positive Mycoplasma/Ureaplasma and other bacteria had significantly higher AF IL-8 levels and a significantly shorter amniocentesis-to-delivery interval. Our newly established PCR method is useful for detecting IA microorganisms. Polymicrobial infection with Mycoplasma/Ureaplasma and other bacteria induces severe IA inflammation associated with poor perinatal prognosis in PTL. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of acetanilide herbicides degrading bacteria isolated from tea garden soil.

PubMed

Wang, Yei-Shung; Liu, Jian-Chang; Chen, Wen-Ching; Yen, Jui-Hung

2008-04-01

Three different green manures were added to the tea garden soils separately and incubated for 40 days. After, incubation, acetanilide herbicides alachlor and metolachlor were spiked into the soils, separately, followed by the isolation of bacteria in each soil at designed intervals. Several bacterial strains were isolated from the soils and identified as Bacillus silvestris, B. niacini, B. pseudomycoides, B. cereus, B. thuringiensis, B. simplex, B. megaterium, and two other Bacillus sp. (Met1 and Met2). Three unique strains with different morphologies were chosen for further investigation. They were B. megaterium, B. niacini, and B. silvestris. The isolated herbicide-degrading bacteria showed optimal performance among three incubation temperatures of 30 degrees C and the best activity in the 10 to 50 microg/ml concentration of the herbicide. Each bacterial strain was able to degrade more than one kind of test herbicides. After incubation for 119 days, B. cereus showed the highest activity to degrade alachlor and propachlor, and B. thuringiensis to degrade metolachlor.

Large-Scale Submerged Aquatic Vegetation Restoration in Chesapeake Bay: Status Report, 2003-2006

DTIC Science & Technology

2008-06-01

42 Can probiotic bacteria enhance SAV growth...using oyster restoration to improve water clarity enough to promote survival of SAV planted nearby. The second looked for candidates for probiotics ...Appendix B (p 78). Can probiotic bacteria enhance SAV growth? This study characterized the diverse communities of bacteria attached to the leaves

Lactic Acid Bacteria – Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating a-(1,6) and a-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, we have developed improved...

Systematic review and meta-analysis of flow cytometry in urinary tract infection screening.

PubMed

Shang, Yan-Jun; Wang, Qian-Qian; Zhang, Jian-Rong; Xu, Yu-Lian; Zhang, Wei-Wei; Chen, Yan; Gu, Ming-Li; Hu, Zhi-De; Deng, An-Mei

2013-09-23

Automated urine sediment analysis of white blood cells (WBCs) and bacteria is a promising approach for urinary tract infections (UTIs) screening. However, available data on their screening efficacy is inconsistent. English articles from Pubmed, EMBASE, and Web of Science published before December 1, 2012 were analyzed. The Quality Assessment for Studies of Diagnostic Accuracy (QUADAS) tool was used to evaluate the quality of eligible studies. Performance characteristics of WBCs and bacteria (sensitivity, specificity, and other measures of accuracy) were pooled and examined by random-effects models. Nineteen studies containing 22,305 samples were included. Pooled sensitivities were 0.87 (95% confidence interval [CI], 0.86-0.89) for WBCs and 0.92 (95% CI, 0.91-0.93) for bacteria. Corresponding pooled specificities were 0.67 (95% CI, 0.66-0.68) for WBCs and 0.60 (95% CI, 0.59-0.61) for bacteria. Areas under the summary receiver operating characteristics curves were 0.87 and 0.93 for WBCs and bacteria, respectively. The major limitation of eligible studies was that enrolled subjects were often not representative of clinical patient populations in which UTI would be suspected. WBC and bacterial measurements by the UF-100 and UF-1000i are useful indicators in UTI screening; however, the performances of these systems should be rigorously evaluated by additional studies. Copyright © 2013 Elsevier B.V. All rights reserved.

Fermentation performance optimization in an ectopic fermentation system.

PubMed

Yang, Xiaotong; Geng, Bing; Zhu, Changxiong; Li, Hongna; He, Buwei; Guo, Hui

2018-07-01

Ectopic fermentation systems (EFSs) were developed for wastewater treatment. Previous studies have investigated the ability of thermophilic bacteria to improve fermentation performance in EFS. Continuing this research, we evaluated EFS performance using principle component analysis and investigated the addition of different proportions of cow dung. Viable bacteria communities were clustered and identified using BOX-AIR-based repetitive extragenic palindromic-PCR and 16S rDNA analysis. The results revealed optimal conditions for the padding were maize straw inoculated with thermophilic bacteria. Adding 20% cow dung yielded the best pH values (6.94-8.56), higher temperatures, increased wastewater absorption, improved litter quality, and greater microbial quantities. The viable bacteria groups were enriched by the addition of thermophilic consortium, and exogenous strains G21, G14, G4-1, and CR-15 were detected in fermentation process. The proportion of Bacillus species in treatment groups reached 70.37% after fermentation, demonstrating that thermophilic bacteria, especially Bacillus, have an important role in EFS, supporting previous predictions. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Clinical observation of the effects of FE combined enzymes on the infection of the granulation burn wound during late post burns stage].

PubMed

Zheng, Ji; Liu, Xu-sheng; Huang, Yue-sheng; Liu, Chun-yu

2006-02-01

To observe the effects of combined FE enzymes on the infection of the granulation burn wound during late postburn stage in controlling burn wound infection caused by common antibiotic resistant bacteria. Thirty patients in our burn ward were enrolled and were randomly divided into A [treated with combined FE enzymes (50 ml dissolved in 0-150 ml normal saline to reach the final concentration of 1-3 U/ml)] and B (treated with gentamicin) groups, with 15 patients in each group. Several layers of gauze, either soaked with combined FE enzyme in A or gentamicin in B group, were used to cover the burn wounds once to twice a day. Bacterial culture from the burn wound exudation before and after drug administration was done before the application of the agents. The bacteria in the burn wounds and their susceptibility to antibiotics were identified. The healing time of the burn wounds was recorded. Furthermore, the healing rate of the burn wound was recorded on the 3rd, 5th, 8th, 10th and 12th post skin grafting days (PSGD). The dominating bacteria in the burn wounds in both groups were Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae and MRSA. The susceptibility rate of bacteria ( MRSA, Staphylococcus epidermidis, Staphylococcus saprophyte, Pseudomonas aeruginosa, Escherichia coli and Enterobacter cloacae) to combined FE enzyme was 93.8%, 100.0%, 100.0%, 100.0%, 100.0% and 95.0% respectively, which were much higher than those in B group (17.6%, 31.3%, 28.6%, 44.0%, 33.3%, 28.0% respectively, P < 0.1. The wound healing time after skin grafting in A group (10.6 +/- 1.5 days) was significantly shorter than that in B group (15.3 +/- 1.7 days, P < 0.01). The wound healing rate on 10 PSGD in A group was (85.4 +/- 2.4)%, and which was only (51.3 +/- 1.5% in B group (P < 0.01) Combined FE enzyme can effectively control burn wound infection, so that the interval between skin grafting and wound healing can be shortened and success rate of skin grafting be improved.

Microbial enhanced heavy crude oil recovery through biodegradation using bacterial isolates from an Omani oil field.

PubMed

Al-Sayegh, Abdullah; Al-Wahaibi, Yahya; Al-Bahry, Saif; Elshafie, Abdulkadir; Al-Bemani, Ali; Joshi, Sanket

2015-09-16

Biodegradation is a cheap and environmentally friendly process that could breakdown and utilizes heavy crude oil (HCO) resources. Numerous bacteria are able to grow using hydrocarbons as a carbon source; however, bacteria that are able to grow using HCO hydrocarbons are limited. In this study, HCO degrading bacteria were isolated from an Omani heavy crude oil field. They were then identified and assessed for their biodegradation and biotransformation abilities under aerobic and anaerobic conditions. Bacteria were grown in five different minimum salts media. The isolates were identified by MALDI biotyper and 16S rRNA sequencing. The nucleotide sequences were submitted to GenBank (NCBI) database. The bacteria were identified as Bacillus subtilis and B. licheniformis. To assess microbial growth and biodegradation of HCO by well-assay on agar plates, samples were collected at different intervals. The HCO biodegradation and biotransformation were determined using GC-FID, which showed direct correlation of microbial growth with an increased biotransformation of light hydrocarbons (C12 and C14). Among the isolates, B. licheniformis AS5 was the most efficient isolate in biodegradation and biotransformation of the HCO. Therefore, isolate AS5 was used for heavy crude oil recovery experiments, in core flooding experiments using Berea core plugs, where an additional 16 % of oil initially in place was recovered. This is the first report from Oman for bacteria isolated from an oil field that were able to degrade and transform HCO to lighter components, illustrating the potential use in HCO recovery. The data suggested that biodegradation and biotransformation processes may lead to additional oil recovery from heavy oil fields, if bacteria are grown in suitable medium under optimum growth conditions.

Endophytic bacteria: prospects and applications for the phytoremediation of organic pollutants.

PubMed

Afzal, Muhammad; Khan, Qaiser M; Sessitsch, Angela

2014-12-01

Recently, there has been an increased effort to enhance the efficacy of phytoremediation of contaminated environments by exploiting plant-microbe interactions. The combined use of plants and endophytic bacteria is an emerging approach for the clean-up of soil and water polluted with organic compounds. In plant-endophyte partnerships, plants provide the habitat as well as nutrients to their associated endophytic bacteria. In response, endophytic bacteria with appropriate degradation pathways and metabolic activities enhance degradation of organic pollutants, and diminish phytotoxicity and evapotranspiration of organic pollutants. Moreover, endophytic bacteria possessing plant growth-promoting activities enhance the plant's adaptation and growth in soil and water contaminated with organic pollutants. Overall, the application of endophytic bacteria gives new insights into novel protocols to improve phytoremediation efficiency. However, successful application of plant-endophyte partnerships for the clean-up of an environment contaminated with organic compounds depends on the abundance and activity of the degrading endophyte in different plant compartments. Although many endophytic bacteria have the potential to degrade organic pollutants and improve plant growth, their contribution to enhance phytoremediation efficiency is still underestimated. A better knowledge of plant-endophyte interactions could be utilized to increase the remediation of polluted soil environments and to protect the foodstuff by decreasing agrochemical residues in food crops. Copyright © 2014 Elsevier Ltd. All rights reserved.

Transgenic plants and associated bacteria for phytoremediation of chlorinated compounds.

PubMed

Van Aken, Benoit; Doty, Sharon Lafferty

2010-01-01

Phytoremediation is the use of plants for the treatment of environmental pollution, including chlorinated organics. Although conceptually very attractive, removal and biodegradation of chlorinated pollutants by plants is a rather slow and inefficient process resulting in incomplete treatment and potential release of toxic metabolites into the environment. In order to overcome inherent limitations of plant metabolic capabilities, plants have been genetically modified, following a strategy similar to the development of transgenic crops: genes from bacteria, fungi, and mammals involved in the metabolism of organic contaminants, such as cytochrome P-450 and glutathione S-transferase, have been introduced into higher plants, resulting in significant improvement of tolerance, removal, and degradation of pollutants. Recently, plant-associated bacteria have been recognized playing a significant role in phytoremediation, leading to the development of genetically modified rhizospheric and endophytic bacteria with improved biodegradation capabilities. Transgenic plants and associated bacteria constitute a new generation of genetically modified organisms for efficient and environmental-friendly treatment of polluted soil and water. This review focuses on recent advances in the development of transgenic plants and bacteria for the treatment of chlorinated pollutants, including chlorinated solvents, polychlorinated phenols, and chlorinated herbicides.

Effects of Bacteria on Artemia franciscana Cultured in Different Gnotobiotic Environments

PubMed Central

Marques, Antonio; Dinh, Thi; Ioakeimidis, Christos; Huys, Geert; Swings, Jean; Verstraete, Willy; Dhont, Jean; Sorgeloos, Patrick; Bossier, Peter

2005-01-01

The use of probiotics is receiving considerable attention as an alternative approach to control microbiota in aquaculture farms, especially in hatching facilities. However, application with consistent results is hampered by insufficient information on their modes of action. To investigate whether dead bacteria (allowing investigation of their nutritional effect) or live bacteria (allowing evaluation of their probiotic effect) have any beneficial effect towards Artemia franciscana and, subsequently, if live bacteria have probiotic effects beyond the effects observed with dead bacteria, a model system was employed using gnotobiotic Artemia as a test organism. Nauplii were cultured in the presence of 10 bacterial strains combined with four different major axenic live feeds (two strains of Saccharomyces cerevisiae and two strains of Dunaliella tertiolecta) differing in their nutritional values. In combination with poor- and medium-quality live feeds, dead bacteria exerted a strong effect on Artemia survival but a rather weak or no effect on individual length and constituted a maximum of only 5.9% of the total ash-free dry weight supplied. These effects were reduced or even disappeared when medium- to good-quality major feed sources were used, possibly due to improvements in the health status of Artemia. Some probiotic bacteria, such as GR 8 (Cytophaga spp.), improved (not always significantly) the performance of nauplii beyond the effect observed with dead bacteria, independently of the feed supplied. The present approach can be an excellent system to study the exact mode of action of bacteria, especially if combined with challenge tests or other types of analysis (e.g., transcriptome and proteonomic analysis). PMID:16085818

Detecting cell division of Pseudomonas aeruginosa bacteria from bright-field microscopy images with hidden conditional random fields.

PubMed

Ong, Lee-Ling S; Xinghua Zhang; Kundukad, Binu; Dauwels, Justin; Doyle, Patrick; Asada, H Harry

2016-08-01

An approach to automatically detect bacteria division with temporal models is presented. To understand how bacteria migrate and proliferate to form complex multicellular behaviours such as biofilms, it is desirable to track individual bacteria and detect cell division events. Unlike eukaryotic cells, prokaryotic cells such as bacteria lack distinctive features, causing bacteria division difficult to detect in a single image frame. Furthermore, bacteria may detach, migrate close to other bacteria and may orientate themselves at an angle to the horizontal plane. Our system trains a hidden conditional random field (HCRF) model from tracked and aligned bacteria division sequences. The HCRF model classifies a set of image frames as division or otherwise. The performance of our HCRF model is compared with a Hidden Markov Model (HMM). The results show that a HCRF classifier outperforms a HMM classifier. From 2D bright field microscopy data, it is a challenge to separate individual bacteria and associate observations to tracks. Automatic detection of sequences with bacteria division will improve tracking accuracy.

Isolation of a bacterial strain, Acinetobacter sp. from centrate wastewater and study of its cooperation with algae in nutrients removal.

PubMed

Liu, Hui; Lu, Qian; Wang, Qin; Liu, Wen; Wei, Qian; Ren, Hongyan; Ming, Caibing; Min, Min; Chen, Paul; Ruan, Roger

2017-07-01

Algae were able to grow healthy on bacteria-containing centrate wastewater in a pilot-scale bioreactor. The batch experiment indicated that the co-cultivation of algae and wastewater-borne bacteria improved the removal efficiencies of chemical oxygen demand and total phosphorus in centrate wastewater to 93.01% and 98.78%, respectively. A strain of beneficial aerobic bacteria, Acinetobacter sp., was isolated and its biochemical characteristics were explored. Synergistic cooperation was observed in the growth of algae and Acinetobacter sp. Removal efficiencies of some nutrients were improved significantly by the co-cultivation of algae and Acinetobacter sp. After treatment, residual nutrients in centrate wastewater reached the permissible discharge limit. The cooperation between algae and Acinetobacter sp. was in part attributed to the exchange of carbon dioxide and oxygen between the algae and bacteria. This synergetic relationship between algae and Acinetobacter sp. provided a promising way to treat the wastewater by improving the nutrients removal and biomass production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biocalcification using Ureolytic Bacteria (UB) for strengthening Interlocking Compressed Earth Blocks (ICEB)

NASA Astrophysics Data System (ADS)

Zamer, M. M.; Irwan, J. M.; Othman, N.; Faisal, S. K.; Anneza, L. H.; Alshalif, A. F.; Teddy, T.

2018-02-01

Interlocking compressed earth blocks (ICEB) are soil based blocks that allows for mortarless construction. This characteristic resulted to faster the process of building walls and required less skilled labor as the blocks are laid dry and lock into place. Recently, implementation in using bacteria as construction material improvement is vigorously used in research in order pursuit the sustainable construction works. This paper provide the results of ureolytic bacteria (UB) throughout enrichment process in soil condition to acclimatize the ICEB environment, compressive strength of 1%, 3% and 5% UB and SEM analysis of ICEB. The bacteria were added as partial replacement of limestone water in ICEB. The results showed the optimal growth achieved based on the days and absorbance from optical density (OD) test which are in 12th days with absorbance of 0.55 whereas the results for strength shows the increment of 15.25% with 5% UB on 28th days of testing compared to control specimen. Therefore this study hopes that positive results from the UB as improving in strength of ICEB which will lead to improve others ICEB properties and others construction materials.

Anti-Helicobacter pylori activities of FEMY-R7 composed of fucoidan and evening primrose extract in mice and humans

PubMed Central

Kim, Tae-Su; Choi, Ehn-Kyoung; Kim, Jihyun; Shin, Kyungha; Lee, Sung-Pyo; Choi, Youngjin; Jeon, Joseph H.

2014-01-01

Helicobacter pylori-eliminating effects of FEMY-R7, composed of fucoidan and evening primrose extract, were investigated in mice and humans. Male C57BL/6 mice were infected with the bacteria by intragastric inoculation (1×109 CFU/mouse) 3 times at 2-day intervals, and simultaneously, orally treated twice a day with 10 or 100 mg/kg FEMY-R7 for 2 weeks. In Campylobcter-like organism-detection test, FEMY-R7 markedly reduced the urease-positive reactivity. In a clinical sudy, human subjects, confirmed to be infected with Helicobacter pylori, were orally administered twice a day with a capsule containing 150 mg FEMY-R7 for 8 weeks. FEMY-R7 significantly decreased both the Delta over baseline-value in urea breath test and the serum pepsinogens I and II levels. The results indicate that FEMY-R7 not only eliminates H. pylori from gastric mucosa of animals and humans, but also improves gastric function. PMID:25324874

Sustained antibacterial actions of a new stabilized stannous fluoride dentifrice containing sodium hexametaphosphate.

PubMed

Ramji, Nivedita; Baig, Arif; He, Tao; Lawless, Michelle A; Saletta, Lisa; Suszcynsky-Meister, Elaine; Coggan, John

2005-09-01

Stannous fluoride has been used as a chemotherapeutic agent for years to improve oral health. The benefits of stannous fluoride in controlling caries, plaque, and gingivitis are directly associated with its antimicrobial actions. Recently, a novel dentifrice was developed that combines stannous fluoride with an anticalculus agent, sodium hexa. metaphosphate. A series of independent evaluations were conducted to assess the long-lasting antimicrobial activity of stannous fluoride in the new stannous fluoride/sodium hexametaphosphate dentifrice: an in vitro Live/Dead assay; an in vivo Plaque Glycolysis and Regrowth Model study; a rapid in vitro salivary bacteria metabolic activity study; and a 12-hour in vivo tin-retention study. In the Live/Dead study, the new stannous fluoride/sodium hexametaphosphate dentifrice killed approximately 90% to 99% of the salivary microbes 16 hours after a single exposure. Similarly, the stannous fluoride dentifrice produced statistically significant reductions in plaque acid production and plaque regrowth activity compared to plaque treated with a standard fluoride dentifrice at all time intervals measured after product exposure (15 and 45 minutes). Results from the final two studies collectively demonstrated the presence of total soluble tin, which serves as a marker for the active stannous fluoride, at levels above the minimum concentration for inhibition of salivary bacteria metabolic activity 12 hours posttreatment. These findings confirm the long-lasting antibacterial action of the new stannous fluoride dentifrice, which serves as a basis for its therapeutic benefits.

Gut Bacteria Affect Immunotherapy Response

Cancer.gov

Three new studies have identified intestinal bacteria that appear to influence the response to checkpoint inhibitors. This Cancer Currents blog post explains how the researchers think their findings could be used to improve patients’ responses to these immunotherapy drugs.

Successful elimination of extended-spectrum beta-lactamase (ESBL)-producing nosocomial bacteria at a neonatal intensive care unit.

PubMed

Szél, Borbála; Reiger, Zsolt; Urbán, Edit; Lázár, Andrea; Mader, Krisztina; Damjanova, Ivelina; Nagy, Kamilla; Tálosi, Gyula

2017-06-01

Extended-spectrum beta-lactamase (ESBL)-producing Gram-negative bacteria are highly dangerous to neonates. At our Neonatal Intensive Care Unit (NICU), the presence of these bacteria became so threatening in 2011 that immediate intervention was required. This study was conducted during a nearly two-year period consisting of three phases: retrospective (9 months), educational (3 months) and prospective (9 months). Based on retrospective data analysis, a complex management plan was devised involving the introduction of the INSURE protocol, changes to the antibiotic regimen, microbiological screening at short intervals, progressive feeding, a safer bathing protocol, staff hand hygiene training and continuous monitoring of the number of newly infected and newly colonized patients. During these intervals, a total of 355 patients were monitored. Both ESBL-producing Enterobacter cloaceae and Klebsiella pneumoniae were found (in both patients and environmental samples). In the prospective period a significant reduction could be seen in the average number of both colonized (26/167 patients; P=0.029) and infected (3/167 patients; P=0.033) patients compared to data from the retrospective period regarding colonized (72/188 patients) and infected (9/188 patients) patients. There was a decrease in the average number of patient-days (from 343.72 to 292.44 days per months), though this difference is not significant (P=0.058). During the prospective period, indirect hand hygiene compliance showed a significant increase (from the previous 26.02 to 33.6 hand hygiene procedures per patient per hospital day, P<0.001). Colonizations and infections were rolled back successfully in a multi-step effort that required an interdisciplinary approach.

Successive bacterial colonisation of pork and its implications for forensic investigations.

PubMed

Handke, Jessica; Procopio, Noemi; Buckley, Michael; van der Meer, Dieudonne; Williams, Graham; Carr, Martin; Williams, Anna

2017-12-01

Bacteria are considered one of the major driving forces of the mammalian decomposition process and have only recently been recognised as forensic tools. At this point, little is known about their potential use as 'post-mortem clocks'. This study aimed to establish the proof of concept for using bacterial identification as post-mortem interval (PMI) indicators, using a multi-omics approach. Pieces of pork were placed in the University's outdoor facility and surface swabs were taken at regular intervals up to 60 days. Terminal restriction fragment length polymorphism (T-RFLP) of the 16S rDNA was used to identify bacterial taxa. It succeeded in detecting two out of three key contributors involved in decomposition and represents the first study to reveal Vibrionaceae as abundant on decomposing pork. However, a high fraction of present bacterial taxa could not be identified by T-RFLP. Proteomic analyses were also performed at selected time points, and they partially succeeded in the identification of precise strains, subspecies and species of bacteria that colonized the body after different PMIs. T-RFLP is incapable of reliably and fully identifying bacterial taxa, whereas proteomics could help in the identification of specific strains of bacteria. Nevertheless, microbial identification by next generation sequencing might be used as PMI clock in future investigations and in conjunction with information provided by forensic entomologists. To the best of our knowledge, this work represents the first attempt to find a cheaper and easily accessible, culture-independent alternative to high-throughput techniques to establish a 'microbial clock', in combination with proteomic strategies to address this issue. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of six methods for isolating mycobacteria from swine lymph nodes.

PubMed

Thoen, C O; Richards, W D; Jarnagin, J L

1974-03-01

Six laboratory methods were compared for isolating acid-fast bacteria. Tuberculous lymph nodes from each of 48 swine as identified by federal meat inspectors were processed by each of the methods. Treated tissue suspensions were inoculated onto each of eight media which were observed at 7-day intervals for 9 weeks. There were no statistically significant differences between the number of Mycobacterium avium complex bacteria isolated by each of the six methods. Rapid tissue preparation methods involving treatment with 2% sodium hydroxide or treatment with 0.2% zephiran required only one-third to one-fourth the processing time as a standard method. There were small differences in the amount of contamination among the six methods, but no detectable differences in the time of first appearance of M. avium complex colonies.

STUDIES ON LUMINOUS BACTERIA

PubMed Central

Morrison, Thomas F.

1925-01-01

1. A method has been described whereby the intensity of the light of luminous bacteria may be measured in a quantitative manner. 2. It is pointed out that the temperature coefficients for light intensity do not follow the van't Hoff rule, but are higher and vary with each 10° temperature interval. 3. From a comparison with other data it is found that the process is not a simple one, but that the observed curve is the resultant of several reactions which proceed simultaneously. 4. The discrepancies in the temperature coefficients in the neighborhood of the "optimum temperature" may be due to a process of coagulation of the colloidal particles of the enzyme. This coagulation will tend to cause a deviation of the curve away from that normal for chemical reactions. PMID:19872179

Application of an oregano oil nanoemulsion to the control of foodborne bacteria on fresh lettuce.

PubMed

Bhargava, Kanika; Conti, Denise S; da Rocha, Sandro R P; Zhang, Yifan

2015-05-01

Although antimicrobial activities of plant essential oils are well documented, challenges remain as to their application in fresh produce due to the hydrophobic nature of essential oils. Oregano oil nanoemulsions were formulated with a food-grade emulsifier and evaluated for their efficacy in inactivating the growth of foodborne bacteria on fresh lettuce. Lettuce was artificially inoculated with Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli O157:H7, followed by a one-minute dipping in oregano oil nanoemulsions (0.05% or 0.1%). Samples were stored at 4 °C and enumerated for bacteria at fixed intervals (0 h, 3 h, 24 h, and 72 h). Compared to control, 0.05% nanoemulsion showed an up to 3.44, 2.31, and 3.05 log CFU/g reductions in L. monocytogenes, S. Typhimurium, and E. coli O157:H7, respectively. Up to 3.57, 3.26, and 3.35 log CFU/g reductions were observed on the same bacteria by the 0.1% treatment. Scanning Electron Microscopy (SEM) demonstrated disrupted bacterial membranes due to the oregano oil treatment. The data suggest that applying oregano oil nanoemulsions to fresh produce may be an effective antimicrobial control strategy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Capability of air filters to retain airborne bacteria and molds in heating, ventilating and air-conditioning (HVAC) systems.

PubMed

Möritz, M; Peters, H; Nipko, B; Rüden, H

2001-07-01

The capability of air filters (filterclass: F6, F7) to retain airborne outdoor microorganisms was examined in field experiments in two heating, ventilating and air conditioning (HVAC) systems. At the beginning of the 15-month investigation period, the first filter stages of both HVAC systems were equipped with new unused air filters. The number of airborne bacteria and molds before and behind the filters were determined simultaneously in 14 days-intervals using 6-stage Andersen cascade impactors. Under relatively dry (< 80% R. H.) and warm (> 12 degrees C) outdoor air conditions air filters led to a marked reduction of airborne microorganism concentrations (bacteria by approximately 70% and molds by > 80%). However, during long periods of high relative humidity (> 80% R. H.) a proliferation of bacteria on air filters with subsequent release into the filtered air occurred. These microorganisms were mainly smaller than 1.1 microns therefore being part of the respirable fraction. The results showed furthermore that one possibility to avoid microbial proliferation is to limit the relative humidity in the area of the air filters to 80% R. H. (mean of 3 days), e.g. by using preheaters in front of air filters in HVAC-systems.

Use of the probiotic Lactobacillus plantarum 299 to reduce pathogenic bacteria in the oropharynx of intubated patients: a randomised controlled open pilot study

PubMed Central

Klarin, Bengt; Molin, Göran; Jeppsson, Bengt; Larsson, Anders

2008-01-01

Introduction Ventilator-associated pneumonia (VAP) is usually caused by aspiration of pathogenic bacteria from the oropharynx. Oral decontamination with antiseptics, such as chlorhexidine (CHX) or antibiotics, has been used as prophylaxis against this complication. We hypothesised that the probiotic bacteria Lactobacillus plantarum 299 (Lp299) would be as efficient as CHX in reducing the pathogenic bacterial load in the oropharynx of tracheally intubated, mechanically ventilated, critically ill patients. Methods Fifty critically ill patients on mechanical ventilation were randomised to either oral mechanical cleansing followed by washing with 0.1% CHX solution or to the same cleansing procedure followed by oral application of an emulsion of Lp299. Samples for microbiological analyses were taken from the oropharynx and trachea at inclusion and at defined intervals thereafter. Results Potentially pathogenic bacteria that were not present at inclusion were identified in oropharyngeal samples from eight of the patients treated with Lp299 and 13 of those treated with CHX (p = 0.13). Analysis of tracheal samples yielded similar results. Lp299 was recovered from the oropharynx of all patients in the Lp299 group. Conclusions In this pilot study, we found no difference between the effect of Lp299 and CHX used in oral care procedures, when we examined the effects of those agents on colonisation of potentially pathogenic bacteria in the oropharynx of intubated, mechanically ventilated patients. PMID:18990201

Potential interactions between heterotrophic archaea and bacteria for degrading particulate organic carbon in marine water column

NASA Astrophysics Data System (ADS)

Liu, H.; Zhang, C.; Tian, J.

2017-12-01

Microbial degradation of organic matter is an essential process in marine carbon cycle, which constitutes an integral component of the marine ecosystem and influences climate change. It is still poorly known, however, how microorganisms interact in utilizing organic matter in the ocean. We have performed metagenomic and qPCR analyses of archaea and bacteria in both particle-attached (>3 mm) and free-living (0.2-3 mm) fractions from surface down to 8727 m in the Mariana Trench. The metagenomic results showed large numbers of genes related to the degradation of valine, leucine, isoleucine and lysine, which were similar between free-living and particle-attached fractions from surface to 6000 m depth intervals. However, the relative abundance of these genes decreased in particle-attached fractions and increased in the free-living fractions below 6000 m depth. This is consistent with the ecophysiology of marine group II (MGII) Euryarchaeota, which are suggested to be able to degrade proteins and lipids. Overall, significant correlation (R2 = 0.95) was observed between the abundance of particle-attached MGII and that of particle-attached heterotrophic bacteria in the Mariana Trench water column; whereas, the correlation was significantly reduced (R2 = 0.34) between free-living MGII and free-living bacteria. We hypothesize that particle-attached MGII and heterotrophic bacteria were mutually beneficial in degrading organic matter, which becomes less important between these organisms in the free-living population.

Coupled effect of chemotaxis and growth on microbial distributions in organic-amended aquifer sediments: Observations from laboratory and field studies

USGS Publications Warehouse

Wang, M.; Ford, R.M.; Harvey, R.W.

2008-01-01

The inter-relationship of growth and chemotactic response exhibited by two common soil-inhabiting bacteria was investigated to determine its impact on bacterial migration. Filter-chambers were used to simulate aquifer sediments characterized by vertical gradients of organic contaminants in both artificial groundwater flow systems in the laboratory and within the screened intervals of observation wells in a sandy aquifer. A labile model contaminant (acetate) was added to the top compartments of the three-part chambers, whereas bacteria with a demonstrated propensity to grow on and chemotactically respond to acetate were introduced to the lower compartments, The motility and chemotactic response of Pseudomonas putida F1 resulted in 40 to 110% greater abundances in the upper compartments and concomitant 22 to 70% depletions in the lower compartments relative to the nonchemotactic controls over 2 days. Bacteria were in greatest abundance within the sand plug that separated the upper and lower compartments where sharp acetate gradients induced a strong chemotactic response. This observation was consistent with predictions from a mathematical model. In agreement with the laboratory results, the down-well filter-chamber incubations with Pseudomonas stutzeri in the aquifer indicated that 91% fewer bacteria resided in the lower compartment than the control experiment without acetate at 15 h. The combination of chemotaxis and growth greatly accelerated the migration of bacteria toward and subsequent abundance at the higher acetate concentration. ?? 2008 American Chemical Society.

Accumulation of Reserve Carbohydrate by Rumen Protozoa and Bacteria in Competition for Glucose

PubMed Central

Denton, Bethany L.; Diese, Leanne E.; Firkins, Jeffrey L.

2014-01-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P < 0.001). When provided a high concentration of glucose (20 mM) (n = 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P = 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. PMID:25548053

Innovative Approaches Using Lichen Enriched Media to Improve Isolation and Culturability of Lichen Associated Bacteria

PubMed Central

Biosca, Elena G.; Flores, Raquel; Santander, Ricardo D.; Díez-Gil, José Luis; Barreno, Eva

2016-01-01

Lichens, self-supporting mutualistic associations between a fungal partner and one or more photosynthetic partners, also harbor non-photosynthetic bacteria. The diversity and contribution of these bacteria to the functioning of lichen symbiosis have recently begun to be studied, often by culture-independent techniques due to difficulties in their isolation and culture. However, culturing as yet unculturable lichenic bacteria is critical to unravel their potential functional roles in lichen symbiogenesis, to explore and exploit their biotechnological potential and for the description of new taxa. Our objective was to improve the recovery of lichen associated bacteria by developing novel isolation and culture approaches, initially using the lichen Pseudevernia furfuracea. We evaluated the effect of newly developed media enriched with novel lichen extracts, as well as the influence of thalli washing time and different disinfection and processing protocols of thalli. The developed methodology included: i) the use of lichen enriched media to mimic lichen nutrients, supplemented with the fungicide natamycin; ii) an extended washing of thalli to increase the recovery of ectolichenic bacteria, thus allowing the disinfection of thalli to be discarded, hence enhancing endolichenic bacteria recovery; and iii) the use of an antioxidant buffer to prevent or reduce oxidative stress during thalli disruption. The optimized methodology allowed significant increases in the number and diversity of culturable bacteria associated with P. furfuracea, and it was also successfully applied to the lichens Ramalina farinacea and Parmotrema pseudotinctorum. Furthermore, we provide, for the first time, data on the abundance of culturable ecto- and endolichenic bacteria that naturally colonize P. furfuracea, R. farinacea and P. pseudotinctorum, some of which were only able to grow on lichen enriched media. This innovative methodology is also applicable to other microorganisms inhabiting these and other lichen species. PMID:27494030

Water quality in the Anacostia River, Maryland and Rock Creek, Washington, D.C.: Continuous and discrete monitoring with simulations to estimate concentrations and yields of nutrients, suspended sediment, and bacteria

USGS Publications Warehouse

Miller, Cherie V.; Chanat, Jeffrey G.; Bell, Joseph M.

2013-01-01

Concentrations and loading estimates for nutrients, suspended sediment, and E. coli bacteria were summarized for three water-quality monitoring stations on the Anacostia River in Maryland and one station on Rock Creek in Washington, D.C. Both streams are tributaries to the Potomac River in the Washington, D.C. metropolitan area and contribute to the Chesapeake Bay estuary. Two stations on the Anacostia River, Northeast Branch at Riverdale, Maryland and Northwest Branch near Hyattsville, Maryland, have been monitored for water quality during the study period from 2003 to 2011 and are located near the shift from nontidal to tidal conditions near Bladensburg, Maryland. A station on Paint Branch is nested above the station on the Northeast Branch Anacostia River, and has slightly less developed land cover than the Northeast and Northwest Branch stations. The Rock Creek station is located in Rock Creek Park, but the land cover in the watershed surrounding the park is urbanized. Stepwise log-linear regression models were developed to estimate the concentrations of suspended sediment, total nitrogen, total phosphorus, and E. coli bacteria from continuous field monitors. Turbidity was the strongest predictor variable for all water-quality parameters. For bacteria, water temperature improved the models enough to be included as a second predictor variable due to the strong dependence of stream metabolism on temperature. Coefficients of determination (R2) for the models were highest for log concentrations of suspended sediment (0.9) and total phosphorus (0.8 to 0.9), followed by E. coli bacteria (0.75 to 0.8), and total nitrogen (0.6). Water-quality data provided baselines for conditions prior to accelerated implementation of multiple stormwater controls in the watersheds. Counties are currently in the process of enhancing stormwater controls in both watersheds. Annual yields were estimated for suspended sediment, total nitrogen, total phosphorus, and E. coli bacteria using the U.S. Geological Survey model LOADEST with hourly time steps of turbidity, flow, and time. Yields of all four parameters were within ranges found in other urbanized watersheds in Chesapeake Bay. Annual yields for all four watersheds over the period of study were estimated for suspended sediment (65,500 – 166,000 kilograms per year per square kilometer; kg/yr/km2), total nitrogen (465 - 911 kg/yr/km2), total phosphorus (36 - 113 kg/yr/km2), and E. coli bacteria (6.0 – 38 x 1012 colony forming units/yr/km2). The length of record was not sufficient to determine trends for any of the water-quality parameters; within confidence intervals of the models, results were similar to loads determined by previous studies for the Northeast and Northwest Branch stations of the Anacostia River.

Combined application of bio-organic phosphate and phosphorus solubilizing bacteria (Bacillus strain MWT 14) improve the performance of bread wheat with low fertilizer input under an arid climate.

PubMed

Tahir, Muhammad; Khalid, Umaira; Ijaz, Muhammad; Shah, Ghulam Mustafa; Naeem, Muhammad Asif; Shahid, Muhammad; Mahmood, Khalid; Ahmad, Naveed; Kareem, Fazal

2018-04-24

This study was aimed to investigate the effect of bio-organic phosphate either alone or in combination with phosphorus solubilizing bacteria strain (Bacillus MWT-14) on the growth and productivity of two wheat cultivars (Galaxy-2013 and Punjab-2011) along with recommended (150-100NPkgha -1 ) and half dose (75-50NPkgha -1 ) of fertilizers. The combined application of bio-organic phosphate and the phosphorous solubilizing bacteria strain at either fertilizer level significantly improved the growth, yield parameters and productivity of both wheat cultivars compared to non-inoculated control treatments. The cultivar Punjab-2011 produced the higher chlorophyll contents, crop growth rate, and the straw yield at half dose of NP fertilizer; while Galaxy-2013, with the combined application of bio-organic phosphate and phosphorous solubilizing bacteria under recommended NP fertilizer dose. Combined over both NP fertilizer levels, the combined use of bio-organic phosphate and phosphorous solubilizing bacteria enhanced the grain yield of cultivar Galaxy-2013 by 54.3% and that of cultivar Punjab-2011 by 83.3%. The combined application of bio-organic phosphate and phosphorous solubilizing bacteria also increased the population of phosphorous solubilizing bacteria, the soil organic matter and phosphorous contents in the soil. In conclusion, the combined application of bio-organic phosphate and phosphorous solubilizing bacteria offers an eco-friendly option to harvest the better wheat yield with low fertilizer input under arid climate. Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

A centrifugal direct recombinase polymerase amplification (direct-RPA) microdevice for multiplex and real-time identification of food poisoning bacteria.

PubMed

Choi, Goro; Jung, Jae Hwan; Park, Byung Hyun; Oh, Seung Jun; Seo, Ji Hyun; Choi, Jong Seob; Kim, Do Hyun; Seo, Tae Seok

2016-06-21

In this study, we developed a centrifugal direct recombinase polymerase amplification (direct-RPA) microdevice for multiplex and real-time identification of food poisoning bacteria contaminated milk samples. The microdevice was designed to contain identical triplicate functional units and each unit has four reaction chambers, thereby making it possible to perform twelve direct-RPA reactions simultaneously. The integrated microdevice consisted of two layers: RPA reagents were injected in the top layer, while spiked milk samples with food poisoning bacteria were loaded into sample reservoirs in the bottom layer. For multiplex bacterial detection, the target gene-specific primers and probes were dried in each reaction chamber. The introduced samples and reagents could be equally aliquoted and dispensed into each reaction chamber by centrifugal force, and then the multiplex direct-RPA reaction was executed. The target genes of bacteria spiked in milk could be amplified at 39 °C without a DNA extraction step by using the direct-RPA cocktails, which were a combination of a direct PCR buffer and RPA enzymes. As the target gene amplification proceeded, the increased fluorescence signals coming from the reaction chambers were recorded in real-time at an interval of 2 min. The entire process, including the sample distribution, the direct-RPA reaction, and the real-time analysis, was accomplished with a custom-made portable genetic analyzer and a miniaturized optical detector. Monoplex, duplex, and triplex food poisoning bacteria (Salmonella enterica, Escherichia coli O157:H7, and Vibrio parahaemolyticus) detection was successfully performed with a detection sensitivity of 4 cells per 3.2 μL of milk samples within 30 min. By implementing the direct-PRA on the miniaturized centrifugal microsystem, the on-site food poisoning bacteria analysis would be feasible with high speed, sensitivity, and multiplicity.

The formation of Staphylococcus aureus enterotoxin in food environments and advances in risk assessment

PubMed Central

Wallin-Carlquist, Nina; Thorup Cohn, Marianne; Lindqvist, Roland; Barker, Gary C; Rådström, Peter

2011-01-01

The recent finding that the formation of staphylococcal enterotoxins in food is very different from that in cultures of pure Staphylococcus aureus sheds new light on, and brings into question, traditional microbial risk assessment methods based on planktonic liquid cultures. In fact, most bacteria in food appear to be associated with surfaces or tissues in various ways, and interaction with other bacteria through molecular signaling is prevalent. Nowadays it is well established that there are significant differences in the behavior of bacteria in the planktonic state and immobilized bacteria found in multicellular communities. Thus, in order to improve the production of high-quality, microbiologically safe food for human consumption, in situ data on enterotoxin formation in food environments are required to complement existing knowledge on the growth and survivability of S. aureus. This review focuses on enterotoxigenic S. aureus and describes recent findings related to enterotoxin formation in food environments, and ways in which risk assessment can take into account virulence behavior. An improved understanding of how environmental factors affect the expression of enterotoxins in foods will enable us to formulate new strategies for improved food safety. PMID:22030860

The formation of Staphylococcus aureus enterotoxin in food environments and advances in risk assessment.

PubMed

Schelin, Jenny; Wallin-Carlquist, Nina; Cohn, Marianne Thorup; Lindqvist, Roland; Barker, Gary C; Rådström, Peter

2011-01-01

The recent finding that the formation of staphylococcal enterotoxins in food is very different from that in cultures of pure Staphylococcus aureus sheds new light on, and brings into question, traditional microbial risk assessment methods based on planktonic liquid cultures. In fact, most bacteria in food appear to be associated with surfaces or tissues in various ways, and interaction with other bacteria through molecular signaling is prevalent. Nowadays it is well established that there are significant differences in the behavior of bacteria in the planktonic state and immobilized bacteria found in multicellular communities. Thus, in order to improve the production of high-quality, microbiologically safe food for human consumption, in situ data on enterotoxin formation in food environments are required to complement existing knowledge on the growth and survivability of S. aureus. This review focuses on enterotoxigenic S. aureus and describes recent findings related to enterotoxin formation in food environments, and ways in which risk assessment can take into account virulence behavior. An improved understanding of how environmental factors affect the expression of enterotoxins in foods will enable us to formulate new strategies for improved food safety.

Enhancement of properties of recycled coarse aggregate concrete using bacteria

NASA Astrophysics Data System (ADS)

Sahoo; Arakha; Sarkar; P; Jha

2016-01-01

Due to rapid construction, necessity for raw materials of concrete, especially coarse aggregate, tends to increase the danger of early exhaustion of the natural resources. An alternative source of raw materials would perhaps delay the advent of this early exhaustion. Recycled coarse aggregate (RCA) plays a great role as an alternative raw material that can replace the natural coarse aggregate (NCA) for concrete. Previous studies show that the properties of RCA concrete are inferior in quality compared to NCA concrete. This article attempts to study the improvement of properties of RCA concrete with the addition of bacteria named as Bacillus subtilis. The experimental investigation was carried out to evaluate the improvement of the compressive strength, capillary water absorption, and drying shrinkage of RCA concrete incorporating bacteria. The compressive strength of RCA concrete is found to be increased by about 20% when the cell concentration of B. subtilis is 106 cells/ml. The capillary water absorption as well as drying shrinkage of RCA are reduced when bacteria is incorporated. The improvement of RCA concrete is confirmed to be due to the calcium carbonate precipitation as observed from the microstructure studies carried out on it such as EDX, SEM, and XRD.

Automated Microbial Metabolism Laboratory

NASA Technical Reports Server (NTRS)

1973-01-01

Development of the automated microbial metabolism laboratory (AMML) concept is reported. The focus of effort of AMML was on the advanced labeled release experiment. Labeled substrates, inhibitors, and temperatures were investigated to establish a comparative biochemical profile. Profiles at three time intervals on soil and pure cultures of bacteria isolated from soil were prepared to establish a complete library. The development of a strategy for the return of a soil sample from Mars is also reported.

Ventilator-associated pneumonia: the importance of oral care in intubated adults.

PubMed

Stonecypher, Karen

2010-01-01

Ventilator-associated pneumonia (VAP) occurs within 24 hours of intubation and mechanical ventilation. Health care costs related to increased patient mortality, extended length of stay, and patient well-being make treatment of VAP a priority in all health care settings. The Institute for Healthcare Improvements has developed the Ventilator Bundle as a group of interventions linked to ventilator care with demonstrated outcome improvements; removal of subglottic secretions is one of these recommendations. Dental plaque and bacterial colonization of pathogens is directly related to microaspiration of bacteria into the lungs. A moist environment in the mouth maintains normal oropharyngeal bacteria, preventing overgrowth of pathogenic bacteria. Frequent oral care to include twice-a-day brushing of the teeth found a 69% reduction in respiratory tract infections.

Bioaugmentation of a biological contact oxidation ditch with indigenous nitrifying bacteria for in situ remediation of nitrogen-rich stream water.

PubMed

Jiao, Yan; Zhao, Qingliang; Jin, Wenbiao; Hao, Xiaodi; You, Shijie

2011-01-01

In this study, specialized bacteria were domesticated and cultivated with polluted stream water. The bioaugmentation of specialized bacteria would significantly enhance the removal efficiency of TN and NH4+-N from 25.9% to 50.3%, and from 34.5% to 60.1%, respectively. Concomitant increases in the number of microbial communities and the proportion of nitrifying bacteria were also identified by the most probable number (MPN) method. PCR-DGGE profiles revealed that the bacterial community could be successfully enriched and the ammonia-oxidizing bacteria communities were shown predominant by the species of Nitrosomonas. The biological contact oxidation ditch (BCOD) system augmented with specialized bacteria can be a viable alternative for treating polluted stream water to achieve improved nitrogen removal. Copyright © 2010 Elsevier Ltd. All rights reserved.

Algal recycling enhances algal productivity and settleability in Pediastrum boryanum pure cultures.

PubMed

Park, Jason B K; Craggs, Rupert J; Shilton, Andy N

2015-12-15

Recycling a portion of gravity harvested algae (i.e. algae and associated bacteria biomass) has been shown to improve both algal biomass productivity and harvest efficiency by maintaining the dominance of a rapidly-settleable colonial alga, Pediastrum boryanum in both pilot-scale wastewater treatment High Rate Algal Ponds (HRAP) and outdoor mesocosms. While algal recycling did not change the relative proportions of algae and bacteria in the HRAP culture, the contribution of the wastewater bacteria to the improved algal biomass productivity and settleability with the recycling was not certain and still required investigation. P. boryanum was therefore isolated from the HRAP and grown in pure culture on synthetic wastewater growth media under laboratory conditions. The influence of recycling on the productivity and settleability of the pure P. boryanum culture was then determined without wastewater bacteria present. Six 1 L P. boryanum cultures were grown over 30 days in a laboratory growth chamber simulating New Zealand summer conditions either with (Pr) or without (Pc) recycling of 10% of gravity harvested algae. The cultures with recycling (Pr) had higher algal productivity than the controls (Pc) when the cultures were operated at both 4 and 3 d hydraulic retention times by 11% and 38% respectively. Furthermore, algal recycling also improved 1 h settleability from ∼60% to ∼85% by increasing the average P. boryanum colony size due to the extended mean cell residence time and promoted formation of large algal bio-flocs (>500 μm diameter). These results demonstrate that the presence of wastewater bacteria was not necessary to improve algal productivity and settleability with algal recycling. Copyright © 2015 Elsevier Ltd. All rights reserved.

Early enhanced local neutrophil recruitment in peritonitis-induced sepsis improves bacterial clearance and survival.

PubMed

Craciun, Florin L; Schuller, Elizabeth R; Remick, Daniel G

2010-12-01

Neutrophils are critical for the rapid eradication of bacterial pathogens, but they also contribute to the development of multiple organ failure in sepsis. We hypothesized that increasing early recruitment of neutrophils to the focus of infection will increase bacterial clearance and improve survival. Sepsis was induced in mice, using cecal ligation and puncture (CLP); blood samples were collected at 6 and 24 h; and survival was followed for 28 d. In separate experiments, peritoneal bacteria and inflammatory cells were measured. Septic mice predicted to die based on IL-6 levels (Die-P) had higher concentrations of CXCL1 and CXCL2 in the peritoneum and plasma compared with those predicted to live (Live-P). At 6 h, Live-P and Die-P had equivalent numbers of peritoneal neutrophils and bacteria. In Die-P mice the number of peritoneal bacteria increased between 6 and 24 h post-CLP, whereas in Live-P it decreased. The i.p. injection of CXCL1 and CXCL2 in naive mice resulted in local neutrophil recruitment. When given immediately after CLP, CXC chemokines increased peritoneal neutrophil recruitment at 6 h after CLP. This early increase in neutrophils induced by exogenous chemokines resulted in significantly fewer peritoneal bacteria by 24 h [CFU (log) = 6.04 versus 4.99 for vehicle versus chemokine treatment; p < 0.05]. Chemokine treatment significantly improved survival at both 5 d (40 versus 72%) and 28 d (27 versus 52%; p < 0.02 vehicle versus chemokines). These data demonstrate that early, local treatment with CXC chemokines enhances neutrophil recruitment and clearance of bacteria as well as improves survival in the CLP model of sepsis.

Establishment of the first international repository for transfusion-relevant bacteria reference strains: ISBT working party transfusion-transmitted infectious diseases (WP-TTID), subgroup on bacteria.

PubMed

Störmer, M; Arroyo, A; Brachert, J; Carrero, H; Devine, D; Epstein, J S; Gabriel, C; Gelber, C; Goodrich, R; Hanschmann, K-M; Heath, D G; Jacobs, M R; Keil, S; de Korte, D; Lambrecht, B; Lee, C-K; Marcelis, J; Marschner, S; McDonald, C; McGuane, S; McKee, M; Müller, T H; Muthivhi, T; Pettersson, A; Radziwon, P; Ramirez-Arcos, S; Reesink, H W; Rojo, J; Rood, I; Schmidt, M; Schneider, C K; Seifried, E; Sicker, U; Wendel, S; Wood, E M; Yomtovian, R A; Montag, T

2012-01-01

Bacterial contamination of platelet concentrates (PCs) still remains a significant problem in transfusion with potential important clinical consequences, including death. The International Society of Blood Transfusion Working Party on Transfusion-Transmitted Infectious Diseases, Subgroup on Bacteria, organised an international study on Transfusion-Relevant Bacteria References to be used as a tool for development, validation and comparison of both bacterial screening and pathogen reduction methods. Four Bacteria References (Staphylococcus epidermidis PEI-B-06, Streptococcus pyogenes PEI-B-20, Klebsiella pneumoniae PEI-B-08 and Escherichia coli PEI-B-19) were selected regarding their ability to proliferate to high counts in PCs and distributed anonymised to 14 laboratories in 10 countries for identification, enumeration and bacterial proliferation in PCs after low spiking (0·3 and 0·03 CFU/ml), to simulate contamination occurring during blood donation. Bacteria References were correctly identified in 98% of all 52 identifications. S. pyogenes and E. coli grew in PCs in 11 out of 12 laboratories, and K. pneumoniae and S. epidermidis replicated in all participating laboratories. The results of bacterial counts were very consistent between laboratories: the 95% confidence intervals were for S. epidermidis: 1·19-1·32 × 10(7) CFU/ml, S. pyogenes: 0·58-0·69 × 10(7) CFU/ml, K. pneumoniae: 18·71-20·26 × 10(7) CFU/ml and E. coli: 1·78-2·10 × 10(7) CFU/ml. The study was undertaken as a proof of principle with the aim to demonstrate (i) the quality, stability and suitability of the bacterial strains for low-titre spiking of blood components, (ii) the property of donor-independent proliferation in PCs, and (iii) their suitability for worldwide shipping of deep frozen, blinded pathogenic bacteria. These aims were successfully fulfilled. The WHO Expert Committee Biological Standardisation has approved the adoption of these four bacteria strains as the first Repository for Transfusion-Relevant Bacteria Reference Strains and, additionally, endorsed as a project the addition of six further bacteria strain preparations suitable for control of platelet contamination as the next step of enlargement of the repository. © 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.

Fermentative preparation of functional drink from Punica granatum using lactic acid bacteria and exploring its anti-tumor potential

NASA Astrophysics Data System (ADS)

Murthy, Shruthi N.; Patnaik, Amie; Srinivasan, Nandini; Selvarajan, E.; Nivetha, A.; Mohanasrinivasan, V.

2017-11-01

In the present research work probiotic pomegranate juice production by fermentation was carried out using two different strains such as Lactobacillus plantarum VITES07 and Lactobacillus acidophilus NCIM2903 (Lactic acid bacteria). Fermented pomegranate juice was carried out at room temperature for 72h. During the fermentation period at regular intervals viable cells was determined. Efficiency of the fermented juice was analysed for 4 weeks under refrigerated condition at 4˚C. Total phenolics, sugar concentration, antioxidant potential, and antibacterial activity were determined. Organic acid concentration was determined by HPLC with retention time of a compound at 9.1 can be suspected to be Kaempferol hexoside and functional group was determined by FTIR also LCMS analysis was carried out to enumerate the chemical composition of the fermented juice.

Effect of a prolonged stay in a locked environment on the microbial flora in dogs

NASA Technical Reports Server (NTRS)

Balish, E.; Shih, C.-N.; Yale, C. E.; Mandel, A. D.

1974-01-01

Ten purebred Beagle dogs (all males) were used to determine the effect of a prolonged stay in a locked environment (i.e., no exogenous microbial contamination) on the microbial flora. At monthly intervals the microbial profile (feces, nose, and throat) of each dog was assessed. After 12 months it was found there was no drastic alteration or simplification of the microbial profile of isolated or control dogs. Although isolated dogs had slightly higher levels of anaerobic bacteria and somewhat lower levels of enterococci, the major groups of anaerobic, aerobic, and facultative bacteria remained qualitatively and quantitatively similar for the 12-month study period. Although they were only minor components of the fecal flora, Candida albicans and Shigella sonnei were consistently isolated in larger numbers from the dogs in the locked environment.

Temporal Synchronization Analysis for Improving Regression Modeling of Fecal Indicator Bacteria Levels

EPA Science Inventory

Multiple linear regression models are often used to predict levels of fecal indicator bacteria (FIB) in recreational swimming waters based on independent variables (IVs) such as meteorologic, hydrodynamic, and water-quality measures. The IVs used for these analyses are traditiona...

Weed-Suppressive Soil Bacteria to Reduce Cheatgrass and Improve Vegetation Diversity on ITD Rights-of-Way

DOT National Transportation Integrated Search

2017-06-01

Transportation departments are challenged by the invasion of downy brome (cheatgrass) and medusahead. The reduction of downy brome (cheat grass) by Weed Suppressive Bacteria (WSB) Pseudomonas fluorescens strain ACK55 was evaluated on roadsides of I-8...

Improved ICU design reduces acquisition of antibiotic-resistant bacteria: a quasi-experimental observational study

PubMed Central

2011-01-01

Introduction The role of ICU design and particularly single-patient rooms in decreasing bacterial transmission between ICU patients has been debated. A recent change in our ICU allowed further investigation. Methods Pre-move ICU-A and pre-move ICU-B were open-plan units. In March 2007, ICU-A moved to single-patient rooms (post-move ICU-A). ICU-B remained unchanged (post-move ICU-B). The same physicians cover both ICUs. Cultures of specified resistant organisms in surveillance or clinical cultures from consecutive patients staying >48 hours were compared for the different ICUs and periods to assess the effect of ICU design on acquisition of resistant organisms. Results Data were collected for 62, 62, 44 and 39 patients from pre-move ICU-A, post-move ICU-A, pre-move ICU-B and post-move ICU-B, respectively. Fewer post-move ICU-A patients acquired resistant organisms (3/62, 5%) compared with post-move ICU-B patients (7/39, 18%; P = 0.043, P = 0.011 using survival analysis) or pre-move ICU-A patients (14/62, 23%; P = 0.004, P = 0.012 on survival analysis). Only the admission period was significant for acquisition of resistant organisms comparing pre-move ICU-A with post-move ICU-A (hazard ratio = 5.18, 95% confidence interval = 1.03 to 16.06; P = 0.025). More antibiotic-free days were recorded in post-move ICU-A (median = 3, interquartile range = 0 to 5) versus post-move ICU-B (median = 0, interquartile range = 0 to 4; P = 0.070) or pre-move ICU-A (median = 0, interquartile range = 0 to 4; P = 0.017). Adequate hand hygiene was observed on 140/242 (58%) occasions in post-move ICU-A versus 23/66 (35%) occasions in post-move ICU-B (P < 0.001). Conclusions Improved ICU design, and particularly use of single-patient rooms, decreases acquisition of resistant bacteria and antibiotic use. This observation should be considered in future ICU design. PMID:21914222

Improved ICU design reduces acquisition of antibiotic-resistant bacteria: a quasi-experimental observational study.

PubMed

Levin, Phillip D; Golovanevski, Mila; Moses, Allon E; Sprung, Charles L; Benenson, Shmuel

2011-01-01

The role of ICU design and particularly single-patient rooms in decreasing bacterial transmission between ICU patients has been debated. A recent change in our ICU allowed further investigation. Pre-move ICU-A and pre-move ICU-B were open-plan units. In March 2007, ICU-A moved to single-patient rooms (post-move ICU-A). ICU-B remained unchanged (post-move ICU-B). The same physicians cover both ICUs. Cultures of specified resistant organisms in surveillance or clinical cultures from consecutive patients staying >48 hours were compared for the different ICUs and periods to assess the effect of ICU design on acquisition of resistant organisms. Data were collected for 62, 62, 44 and 39 patients from pre-move ICU-A, post-move ICU-A, pre-move ICU-B and post-move ICU-B, respectively. Fewer post-move ICU-A patients acquired resistant organisms (3/62, 5%) compared with post-move ICU-B patients (7/39, 18%; P = 0.043, P = 0.011 using survival analysis) or pre-move ICU-A patients (14/62, 23%; P = 0.004, P = 0.012 on survival analysis). Only the admission period was significant for acquisition of resistant organisms comparing pre-move ICU-A with post-move ICU-A (hazard ratio = 5.18, 95% confidence interval = 1.03 to 16.06; P = 0.025). More antibiotic-free days were recorded in post-move ICU-A (median = 3, interquartile range = 0 to 5) versus post-move ICU-B (median = 0, interquartile range = 0 to 4; P = 0.070) or pre-move ICU-A (median = 0, interquartile range = 0 to 4; P = 0.017). Adequate hand hygiene was observed on 140/242 (58%) occasions in post-move ICU-A versus 23/66 (35%) occasions in post-move ICU-B (P < 0.001). Improved ICU design, and particularly use of single-patient rooms, decreases acquisition of resistant bacteria and antibiotic use. This observation should be considered in future ICU design.

Probiotic bacteria cell walls stimulate the activity of the intestinal epithelial cells and macrophage functionality.

PubMed

Lemme-Dumit, J M; Polti, M A; Perdigón, G; Galdeano, C Maldonado

2018-01-29

The effect of oral administration of probiotic bacteria cell walls (PBCWs) in the stimulation of the immune system in healthy BALB/c mice was evaluated. We focused our investigation mainly on intestinal epithelial cells (IECs) which are essential for coordinating an adequate mucosal immune response and on the functionality of macrophages. The probiotic bacteria and their cell walls were able to stimulate the IECs exhibiting an important activation and cytokine releases. Supplementation with PBCWs promoted macrophage activation from peritoneum and spleen, indicating that the PBCWs oral administration was able to improve the functionality of the macrophages. In addition, the PBCWs increased immunoglobulin A (IgA)-producing cells in the gut lamina propria in a similar way to probiotic bacteria, but this supplementation did not have an effect on the population of goblet cells in the small intestine epithelium. These results indicate that the probiotic bacteria and their cell walls have an important immunoregulatory effect on the IECs without altering the homeostatic environment but with an increase in IgA+ producing cells and in the innate immune cells, mainly those distant from the gut such as spleen and peritoneum. These findings about the capacity of the cell walls from probiotic bacteria to stimulate key cells, such as IECs and macrophages, and to improve the functioning of the immune system, suggest that those structures could be applied as a new oral adjuvant.

Accumulation of reserve carbohydrate by rumen protozoa and bacteria in competition for glucose.

PubMed

Denton, Bethany L; Diese, Leanne E; Firkins, Jeffrey L; Hackmann, Timothy J

2015-03-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P < 0.001). When provided a high concentration of glucose (20 mM) (n = 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P = 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The effect of laminar air flow and door openings on operating room contamination.

PubMed

Smith, Eric B; Raphael, Ibrahim J; Maltenfort, Mitchell G; Honsawek, Sittisak; Dolan, Kyle; Younkins, Elizabeth A

2013-10-01

We evaluate the association of laminar airflow (LAF) and OR traffic with intraoperative contamination rates. Two sterile basins were placed in each room during 81 cases, one inside and one outside the LAF. One Replicate Organism Detection and Counting (RODAC) plate from each basin was sent for culture at successive 30-minute intervals from incision time until wound closure. At successive 30-minute intervals more plates were contaminated outside than inside the LAF. A negative binomial model showed that the bacteria colony forming units (CFU) depended on whether there were any door openings (P=0.02) and the presence of LAF (P=0.003). LAF decreases CFU by 36.6%. LAF independently reduces the risk of contamination and microbial counts for surgeries lasting 90 minutes or less. © 2013.

Dental plaque bacteria with reduced susceptibility to chlorhexidine are multidrug resistant.

PubMed

Saleem, Hafiz Ghulam Murtaza; Seers, Christine Ann; Sabri, Anjum Nasim; Reynolds, Eric Charles

2016-09-15

Chlorhexidine (CHX) is used in oral care products to help control dental plaque. In this study dental plaque bacteria were grown on media containing 2 μg/ml chlorhexidine gluconate to screen for bacteria with reduced CHX susceptibility. The isolates were characterized by 16S rRNA gene sequencing and antibiotic resistance profiles were determined using the disc diffusion method. The isolates were variably resistant to multiple drugs including ampicillin, kanamycin, gentamicin and tetracycline. Two species, Chryseobacterium culicis and Chryseobacterium indologenes were able to grow planktonically and form biofilms in the presence of 32 μg/ml CHX. In the CHX and multidrug resistant C. indologenes we demonstrated a 19-fold up-regulation of expression of the HlyD-like periplasmic adaptor protein of a tripartite efflux pump upon exposure to 16 μg/ml CHX suggesting that multidrug resistance may be mediated by this system. Exposure of biofilms of these resistant species to undiluted commercial CHX mouthwash for intervals from 5 to 60 s indicated that the mouthwash was unlikely to eliminate them from dental plaque in vivo. The study highlights the requirement for increased vigilance of the presence of multidrug resistant bacteria in dental plaque and raises a potential risk of long-term use of oral care products containing antimicrobial agents for the control of dental plaque.

The Role of Plant Growth-Promoting Bacteria in Metal Phytoremediation.

PubMed

Kong, Zhaoyu; Glick, Bernard R

2017-01-01

Phytoremediation is a promising technology that uses plants and their associated microbes to clean up contaminants from the environment. In recent years, phytoremediation assisted by plant growth-promoting bacteria (PGPB) has been highly touted for cleaning up toxic metals from soil. PGPB include rhizospheric bacteria, endophytic bacteria and the bacteria that facilitate phytoremediation by other means. This review provides information about the traits and mechanisms possessed by PGPB that improve plant metal tolerance and growth, and illustrate mechanisms responsible for plant metal accumulation/translocation in plants. Several recent examples of phytoremediation of metals facilitated by PGPB are reviewed. Although many encouraging results have been reported in the past years, there have also been numerous challenges encountered in phytoremediation in the field. To implement PGPB-assisted phytoremediation of metals in the natural environment, there is also a need to critically assess the ecological effects of PGPB, especially for those nonnative bacteria. © 2017 Elsevier Ltd All rights reserved.

Microbiologic tests in epidemiologic studies: are they reproducible?

PubMed

Aass, A M; Preus, H R; Zambon, J J; Gjermo, P

1994-12-01

Microbiologic assessments are often included in longitudinal studies to elucidate the significance of the association of certain Gram-negative bacteria and the development of periodontal diseases. In such studies, the reliability of methods is crucial. There are several methods to identify putative pathogens, and some of them are commercially available. The purpose of the present study was to compare the reproducibility of four different methods for detecting Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia in order to evaluate their usefulness in epidemiologic studies. The test panel consisted of 10 young subjects and 10 adult periodontitis patients. Subgingival plaque was sampled from sites showing bone loss and "healthy" control sites. The four different methods for detecting the target bacteria were 1) cultivation, 2) Evalusite (a chair-side kit based on ELISA), 3) OmniGene, Inc, based on DNA probes, and 4) indirect immunofluorescence (IIF). The test procedure was repeated after a 1-wk interval and was performed by one examiner. Sites reported to be positive for a microorganism by any of the four methods at one or both examinations were considered to be positive for that organism and included in the analysis. The reproducibility of the four methods was low. The IIF and the cultivation methods showed somewhat higher reproducibility than did the commercial systems. A second test was done for Evalusite, three paper points for sampling being used instead of one as described in the manual. The reproducibility of the second test was improved, indicating that the detection level of the system may influence the reliability.

A prebiotic role of Ecklonia cava improves the mortality of Edwardsiella tarda-infected zebrafish models via regulating the growth of lactic acid bacteria and pathogen bacteria.

PubMed

Lee, WonWoo; Oh, Jae Young; Kim, Eun-A; Kang, Nalae; Kim, Kil-Nam; Ahn, Ginnae; Jeon, You-Jin

2016-07-01

In this study, the beneficial prebiotic roles of Ecklonia cava (E. cava, EC) were evaluated on the growth of lactic acid bacteria (LAB) and pathogen bacteria and the mortality of pathogen-bacteria infected zebrafish model. The result showed that the original E. cava (EC) led to the highest growth effects on three LABs (Lactobacillus brevis, L. brevis; Lactobacillus pentosus, L. pentosus; Lactobacillus plantarum; L. plantarum) and it was dose-dependent manners. Also, EC, its Celluclast enzymatic (ECC) and 100% ethanol extracts (ECE) showed the anti-bacterial activities on the fish pathogenic bacteria such as (Edwardsiella tarda; E. tarda, Streptococcus iniae; S. iniae, and Vibrio harveyi; V. harveyi). Interestingly, EC induced the higher production of the secondary metabolites from L. plantarum in MRS medium. The secondary metabolites produced by EC significantly inhibited the growth of pathogen bacteria. In further in vivo study, the co-treatment of EC and L. plantarum improved the growth and mortality of E. tarda-infected zebrafish as regulating the expression of inflammatory molecules such as iNOS and COX2. Taken together, our present study suggests that the EC plays an important role as a potential prebiotic and has a protective effect against the infection caused by E. tarda injection in zebrafish. Also, our conclusion from this evidence is that EC can be used and applied as a useful prebiotic. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of chemical oxidation on indigenous bacteria and mobilization of nutrients and subsequent bioremediation of crude oil-contaminated soil.

PubMed

Xu, Jinlan; Deng, Xin; Cui, Yiwei; Kong, Fanxing

2016-12-15

Fenton pre-oxidation provides nutrients to promote bioremediation. However, the effects of the indigenous bacteria that remain following Fenton oxidation on nutrient mobilization and subsequent bioremediation remain unclear. Experiments were performed with inoculation with native bacteria and foreign bacteria or without inoculation after four regimens of stepwise pre-oxidations. The effects of the indigenous bacteria remaining after stepwise oxidation on nutrient mobilization and subsequent bioremediation over 80 days were investigated. After stepwise Fenton pre-oxidation at a low H 2 O 2 concentration (225×4), the remaining indigenous bacterial populations reached their peak (4.8±0.17×10 6 CFU/g), the nutrients were mobilized rapidly, and the subsequent bioremediation of crude oil was improved (biodegradation efficiency of 35%). However, after stepwise Fenton pre-oxidation at a high H 2 O 2 concentration (450×4), only 3.6±0.16×10 3 CFU/g of indigenous bacteria remained, and the indigenous bacteria that degrade C 15 -C 30 alkanes were inhibited. The nutrient mobilization was then highly limited, and only 19% of total petroleum hydrocarbon was degraded. Furthermore, the recovery period after the low H 2 O 2 concentration stepwise Fenton pre-oxidation (225×4) was less than 20 days, which was 20-30 days shorter than with the other pre-oxidation treatments. Therefore, stepwise Fenton pre-oxidation at a low H 2 O 2 concentration protects indigenous bacterial populations and improves the nutrient mobilization and subsequent bioremediation. Copyright © 2016 Elsevier B.V. All rights reserved.

Biotemplating pores with size and shape diversity for Li-oxygen Battery Cathodes.

PubMed

Oh, Dahyun; Ozgit-Akgun, Cagla; Akca, Esin; Thompson, Leslie E; Tadesse, Loza F; Kim, Ho-Cheol; Demirci, Gökhan; Miller, Robert D; Maune, Hareem

2017-04-04

Synthetic porogens provide an easy way to create porous structures, but their usage is limited due to synthetic difficulties, process complexities and prohibitive costs. Here we investigate the use of bacteria, sustainable and naturally abundant materials, as a pore template. The bacteria require no chemical synthesis, come in variable sizes and shapes, degrade easier and are approximately a million times cheaper than conventional porogens. We fabricate free standing porous multiwalled carbon nanotube (MWCNT) films using cultured, harmless bacteria as porogens, and demonstrate substantial Li-oxygen battery performance improvement by porosity control. Pore volume as well as shape in the cathodes were easily tuned to improve oxygen evolution efficiency by 30% and double the full discharge capacity in repeated cycles compared to the compact MWCNT electrode films. The interconnected pores produced by the templates greatly improve the accessibility of reactants allowing the achievement of 4,942 W/kg (8,649 Wh/kg) at 2 A/g e (1.7 mA/cm 2 ).

Biotemplating pores with size and shape diversity for Li-oxygen Battery Cathodes

PubMed Central

Oh, Dahyun; Ozgit-Akgun, Çagla; Akca, Esin; Thompson, Leslie E.; Tadesse, Loza F.; Kim, Ho-Cheol; Demirci, Gökhan; Miller, Robert D.; Maune, Hareem

2017-01-01

Synthetic porogens provide an easy way to create porous structures, but their usage is limited due to synthetic difficulties, process complexities and prohibitive costs. Here we investigate the use of bacteria, sustainable and naturally abundant materials, as a pore template. The bacteria require no chemical synthesis, come in variable sizes and shapes, degrade easier and are approximately a million times cheaper than conventional porogens. We fabricate free standing porous multiwalled carbon nanotube (MWCNT) films using cultured, harmless bacteria as porogens, and demonstrate substantial Li-oxygen battery performance improvement by porosity control. Pore volume as well as shape in the cathodes were easily tuned to improve oxygen evolution efficiency by 30% and double the full discharge capacity in repeated cycles compared to the compact MWCNT electrode films. The interconnected pores produced by the templates greatly improve the accessibility of reactants allowing the achievement of 4,942 W/kg (8,649 Wh/kg) at 2 A/ge (1.7 mA/cm2). PMID:28374862

Synthesis and antibacterial activity of novel 15-membered macrolide derivatives: 4''-carbamate, 11,12-cyclic carbonate-4''-carbamate and 11,4''-di-O-arylcarbamoyl analogs of azithromycin.

PubMed

Ma, Shutao; Ma, Ruixin; Liu, Zhaopeng; Ma, Chenchen; Shen, Xuecui

2009-10-01

4''-Carbamate, 11,12-cyclic carbonate-4''-carbamate and 11,4''-di-O-arylcarbamoyl analogs of azithromycin were designed, synthesized and evaluated. The 4''-carbamate analogs retained excellent activity against erythromycin-susceptible Staphylococcus pneumoniae and showed improved activity against erythromycin-resistant Staphylococcus pneumoniae. Compared with 4''-carbamate analogs, 11,12-cyclic carbonate-4''-carbamate analogs exhibited improved activity against erythromycin-resistant Staphylococcus pneumoniae encoded by the mef gene or the erm and mef genes, and 11,4''-di-O-arylalkylcarbamoyl analogs showed greatly improved activity (0.25-0.5 microg/mL) against erythromycin-resistant Staphylococcus pneumoniae encoded by the erm gene. Among them, the novel series of 11,4''-di-O-arylalkylcarbamoyl analogs 7a-k exhibited potent and balanced activity against susceptible and resistant bacteria. In particular, compounds 7f and 7k were the most effective against susceptible bacteria and resistant bacteria encoded by the erm gene or the mef gene.

The characterization of lactic acid producing bacteria from the rumen of dairy cattle grazing on improved pasture supplemented with wheat and barley grain.

PubMed

Hernandez, J D; Scott, P T; Shephard, R W; Al Jassim, R A M

2008-06-01

To identify and characterize the major lactic acid bacteria in the rumen of dairy cattle grazing improved pasture of rye grass and white clover and receiving a maize silage and grain supplement with and without virginiamycin. Eighty-five bacterial isolates were obtained from the rumen of 16 Holstein-Friesian dairy cows. The isolates were initially grouped on the basis of their Gram morphology and by restriction fragment length polymorphism analysis of the PCR amplified 16S rDNA. A more definitive analysis was undertaken by comparing the 16S rDNA sequences. Many of the isolates were closely related to other previously characterized rumen bacteria, including Streptococcus bovis, Lactobacillus vitulinus, Butyrivibrio fibrisolvens, Prevotella bryantii and Selenomonas ruminantium. The in vitro production of L- and/or D-lactate was seen with all but five of the isolates examined, many of which were also resistant to virginiamycin. Supplementation of grain with virginiamycin may reduce the risk of acidosis but does not prevent its occurrence in dairy cattle grazing improved pasture. This study shows that lactic acid production is caused, not only by various thoroughly researched types of bacteria, but also by others previously identified in the rumen but not further characterized.

Cultivation-Independent Detection of Autotrophic Hydrogen-Oxidizing Bacteria by DNA Stable-Isotope Probing ▿

PubMed Central

Pumphrey, Graham M.; Ranchou-Peyruse, Anthony; Spain, Jim C.

2011-01-01

Knallgas bacteria are a physiologically defined group that is primarily studied using cultivation-dependent techniques. Given that current cultivation techniques fail to grow most bacteria, cultivation-independent techniques that selectively detect and identify knallgas bacteria will improve our ability to study their diversity and distribution. We used stable-isotope probing (SIP) to identify knallgas bacteria in rhizosphere soil of legumes and in a microbial mat from Obsidian Pool in Yellowstone National Park. When samples were incubated in the dark, incorporation of 13CO2 was H2 dependent. SIP enabled the detection of knallgas bacteria that were not detected by cultivation, and the majority of bacteria identified in the rhizosphere soils were betaproteobacteria predominantly related to genera previously known to oxidize hydrogen. Bacteria in soil grew on hydrogen at concentrations as low as 100 ppm. A hydB homolog encoding a putative high-affinity NiFe hydrogenase was amplified from 13C-labeled DNA from both vetch and clover rhizosphere soil. The results indicate that knallgas bacteria can be detected by SIP and populations that respond to different H2 concentrations can be distinguished. The methods described here should be applicable to a variety of ecosystems and will enable the discovery of additional knallgas bacteria that are resistant to cultivation. PMID:21622787

Cultivation-independent detection of autotrophic hydrogen-oxidizing bacteria by DNA stable-isotope probing.

PubMed

Pumphrey, Graham M; Ranchou-Peyruse, Anthony; Spain, Jim C

2011-07-01

Knallgas bacteria are a physiologically defined group that is primarily studied using cultivation-dependent techniques. Given that current cultivation techniques fail to grow most bacteria, cultivation-independent techniques that selectively detect and identify knallgas bacteria will improve our ability to study their diversity and distribution. We used stable-isotope probing (SIP) to identify knallgas bacteria in rhizosphere soil of legumes and in a microbial mat from Obsidian Pool in Yellowstone National Park. When samples were incubated in the dark, incorporation of (13)CO(2) was H(2) dependent. SIP enabled the detection of knallgas bacteria that were not detected by cultivation, and the majority of bacteria identified in the rhizosphere soils were betaproteobacteria predominantly related to genera previously known to oxidize hydrogen. Bacteria in soil grew on hydrogen at concentrations as low as 100 ppm. A hydB homolog encoding a putative high-affinity NiFe hydrogenase was amplified from (13)C-labeled DNA from both vetch and clover rhizosphere soil. The results indicate that knallgas bacteria can be detected by SIP and populations that respond to different H(2) concentrations can be distinguished. The methods described here should be applicable to a variety of ecosystems and will enable the discovery of additional knallgas bacteria that are resistant to cultivation.

Plant-Associated Bacterial Degradation of Toxic Organic Compounds in Soil

PubMed Central

McGuinness, Martina; Dowling, David

2009-01-01

A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review. PMID:19742157

Plant-bacteria partnerships for the remediation of persistent organic pollutants.

PubMed

Arslan, Muhammad; Imran, Asma; Khan, Qaiser Mahmood; Afzal, Muhammad

2017-02-01

High toxicity, bioaccumulation factor and widespread dispersal of persistent organic pollutants (POPs) cause environmental and human health hazards. The combined use of plants and bacteria is a promising approach for the remediation of soil and water contaminated with POPs. Plants provide residency and nutrients to their associated rhizosphere and endophytic bacteria. In return, the bacteria support plant growth by the degradation and detoxification of POPs. Moreover, they improve plant growth and health due to their innate plant growth-promoting mechanisms. This review provides a critical view of factors that affect absorption and translocation of POPs in plants and the limitations that plant have to deal with during the remediation of POPs. Moreover, the synergistic effects of plant-bacteria interactions in the phytoremediation of organic pollutants with special reference to POPs are discussed.

Increasing accuracy in the interval analysis by the improved format of interval extension based on the first order Taylor series

NASA Astrophysics Data System (ADS)

Li, Yi; Xu, Yan Long

2018-05-01

When the dependence of the function on uncertain variables is non-monotonic in interval, the interval of function obtained by the classic interval extension based on the first order Taylor series will exhibit significant errors. In order to reduce theses errors, the improved format of the interval extension with the first order Taylor series is developed here considering the monotonicity of function. Two typical mathematic examples are given to illustrate this methodology. The vibration of a beam with lumped masses is studied to demonstrate the usefulness of this method in the practical application, and the necessary input data of which are only the function value at the central point of interval, sensitivity and deviation of function. The results of above examples show that the interval of function from the method developed by this paper is more accurate than the ones obtained by the classic method.

Cueing listeners to attend to a target talker progressively improves word report as the duration of the cue-target interval lengthens to 2,000 ms.

PubMed

Holmes, Emma; Kitterick, Padraig T; Summerfield, A Quentin

2018-04-25

Endogenous attention is typically studied by presenting instructive cues in advance of a target stimulus array. For endogenous visual attention, task performance improves as the duration of the cue-target interval increases up to 800 ms. Less is known about how endogenous auditory attention unfolds over time or the mechanisms by which an instructive cue presented in advance of an auditory array improves performance. The current experiment used five cue-target intervals (0, 250, 500, 1,000, and 2,000 ms) to compare four hypotheses for how preparatory attention develops over time in a multi-talker listening task. Young adults were cued to attend to a target talker who spoke in a mixture of three talkers. Visual cues indicated the target talker's spatial location or their gender. Participants directed attention to location and gender simultaneously ("objects") at all cue-target intervals. Participants were consistently faster and more accurate at reporting words spoken by the target talker when the cue-target interval was 2,000 ms than 0 ms. In addition, the latency of correct responses progressively shortened as the duration of the cue-target interval increased from 0 to 2,000 ms. These findings suggest that the mechanisms involved in preparatory auditory attention develop gradually over time, taking at least 2,000 ms to reach optimal configuration, yet providing cumulative improvements in speech intelligibility as the duration of the cue-target interval increases from 0 to 2,000 ms. These results demonstrate an improvement in performance for cue-target intervals longer than those that have been reported previously in the visual or auditory modalities.

High-Intensity Interval Training for Improving Postprandial Hyperglycemia

ERIC Educational Resources Information Center

Little, Jonathan P.; Francois, Monique E.

2014-01-01

High-intensity interval training (HIIT) has garnered attention in recent years as a time-efficient exercise option for improving cardiovascular and metabolic health. New research demonstrates that HIIT may be particularly effective for improving postprandial hyperglycemia in individuals with, or at risk for, type 2 diabetes (T2D). These findings…

Short-Term Results in Evaluating a Gingiva-Adhesive Hydrophobic-Chlorhexidine-Gel for Chronic Periodontitis.

PubMed

Sarbu, Ciprian; Rusu, Darian; Călniceanu, Horia; Kasaj, Adrian; Petrutiu, Stefan Adrian; Roman, Alexandra; Soancă, Andrada; PicoȘ, Alina; Stratul, Stefan Ioan; Jentsch, Holger

2014-01-01

Oral mucosa and interproximal spaces of the teeth could favor the colonization of periodontopathogenic bacteria, which could be targeted by chemical antiplaque agents such as chlorhexidine, present in different oral hygiene products, thus improving the control of biofilm growth and delaying microbial accumulation. The study aimed to evaluate whether the use of a hydrophobic gel with good gingival adhesion for 14 days after the scaling and root planing of patients with chronic periodontitis would improve the treatment outcome, when compared with the use of a regular hydrophyllic gel. Patients with moderate disease were included in two study groups. At baseline and 3 months after the treatment the following parameters were recorded: pocket depth, Approximal Plaque Index, Modified Gingival Index, Simplified Oral Hygiene Index, bleeding on probing. Patients received scaling and root planing in two sessions at 24 hours interval. After the treatment, patients in the test group applied the hydrophobic adhesive chlorhexidine gel once a day, every other day, while in the control group the gel was used twice daily. Both treatments resulted in significant improvement in all clinical indices, except Approximal Plaque Index, which deteriorated significantly in both groups. Three months after mechanical treatment, the mean probing depth changed in the test group from 4.16±0.45 mm to 2.80±0.42 mm, and in the control group from 4.16±0.30 to 2.69±0.19. Both adjunctive anti-infective therapies induced clinical improvement 3 months from baseline. The differences between the two treatments were not statistically significant.

Distribution of Legionella pneumophila bacteria and Naegleria and Hartmannella amoebae in thermal saline baths used in balneotherapy.

PubMed

Zbikowska, Elżbieta; Walczak, Maciej; Krawiec, Arkadiusz

2013-01-01

The present study was aimed at investigating the coexistence and interactions between free living amoebae of Naegleria and Hartmannella genera and pathogenic Legionella pneumophila bacteria in thermal saline baths used in balneotherapy in central Poland. Water samples were collected from November 2010 to May 2011 at intervals longer than 1 month. The microorganisms were detected with the use of a very sensitive fluorescence in situ hybridisation method. In addition, the morphology of the amoebae was studied. Despite relatively high salinity level, ranging from 1.5 to 5.0 %, L. pneumophila were found in all investigated baths, although their number never exceeded 10(6) cells dm(-3). Hartmannella were not detected, while Naegleria fowleri were found in one bath. The observation that N. fowleri and L. pneumophila may coexist in thermal saline baths is the first observation emphasising potential threat from these microorganisms in balneotherapy.

Silage review: Foodborne pathogens in silage and their mitigation by silage additives.

PubMed

Queiroz, O C M; Ogunade, I M; Weinberg, Z; Adesogan, A T

2018-05-01

Silage is one of the main ingredients in dairy cattle diets and it is an important source of nutrients, particularly energy and digestible fiber. Unlike properly made and managed silage, poorly made or contaminated silage can also be a source of pathogenic bacteria that may decrease dairy cow performance, reduce the safety and quality dairy products, and compromise animal and human health. Some of the pathogenic bacteria that are frequently or occasionally associated with silage are enterobacteria, Listeria, Bacillus spp., Clostridium spp., and Salmonella. The symptoms caused by these bacteria in dairy cows vary from mild diarrhea and reduced feed intake by Clostridium spp. to death and abortion by Listeria. Contamination of food products with pathogenic bacteria can cause losses of millions of dollars due to recalls of unsafe foods and decreases in the shelf life of dairy products. The presence of pathogenic bacteria in silage is usually due to contamination or poor management during the fermentation, aerobic exposure, or feed-out stages. Silage additives and inoculants can improve the safety of silage as well as the fermentation, nutrient recovery, quality, and shelf life. This review summarizes the literature on the main foodborne pathogens that occasionally infest silage and how additives can improve silage safety. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Roles of Probiotic Lactobacilli Inclusion in Helping Piglets Establish Healthy Intestinal Inter-environment for Pathogen Defense.

PubMed

Yang, Jiajun; Qian, Kun; Wang, Chonglong; Wu, Yijing

2018-06-01

The gastrointestinal tract of pigs is densely populated with microorganisms that closely interact with the host and with ingested feed. Gut microbiota benefits the host by providing nutrients from dietary substrates and modulating the development and function of the digestive and immune systems. An optimized gastrointestinal microbiome is crucial for pigs' health, and establishment of the microbiome in piglets is especially important for growth and disease resistance. However, the microbiome in the gastrointestinal tract of piglets is immature and easily influenced by the environment. Supplementing the microbiome of piglets with probiotic bacteria such as Lactobacillus could help create an optimized microbiome by improving the abundance and number of lactobacilli and other indigenous probiotic bacteria. Dominant indigenous probiotic bacteria could improve piglets' growth and immunity through certain cascade signal transduction pathways. The piglet body provides a permissive habitat and nutrients for bacterial colonization and growth. In return, probiotic bacteria produce prebiotics such as short-chain fatty acids and bacteriocins that benefit piglets by enhancing their growth and reducing their risk of enteric infection by pathogens. A comprehensive understanding of the interactions between piglets and members of their gut microbiota will help develop new dietary interventions that can enhance piglets' growth, protect piglets from enteric diseases caused by pathogenic bacteria, and maximize host feed utilization.

Pretreatment of Cr(VI)-amended soil with chromate-reducing rhizobacteria decreases plant toxicity and increases the yield of Pisum sativum.

PubMed

Soni, Sumit K; Singh, Rakshapal; Singh, Mangal; Awasthi, Ashutosh; Wasnik, Kundan; Kalra, Alok

2014-05-01

Pot culture experiments were performed under controlled greenhouse conditions to investigate whether four Cr(VI)-reducing bacterial strains (SUCR44, SUCR140, SUCR186, and SUCR188) were able to decrease Cr toxicity to Pisum sativum plants in artificially Cr(VI)-contaminated soil. The effect of pretreatment of soil with chromate-reducing bacteria on plant growth, chromate uptake, bioaccumulation, nodulation, and population of Rhizobium was found to be directly influenced by the time interval between bacterial treatment and seed sowing. Pretreatment of soil with SUCR140 (Microbacterium sp.) 15 days before sowing (T+15) showed a maximum increase in growth and biomass in terms of root length (93 %), plant height (94 %), dry root biomass (99 %), and dry shoot biomass (99 %). Coinoculation of Rhizobium with SUCR140 further improved the aforementioned parameter. Compared with the control, coinoculation of SUCR140+R showed a 117, 116, 136, and 128 % increase, respectively, in root length, plant height, dry root biomass, and dry shoot biomass. The bioavailability of Cr(VI) decreased significantly in soil (61 %) and in uptake (36 %) in SUCR140-treated plants; the effects of Rhizobium, however, either alone or in the presence of SUCR140, were not significant. The populations of Rhizobium (126 %) in soil and nodulation (146 %) in P. sativum improved in the presence of SUCR140 resulting in greater nitrogen (54 %) concentration in the plants. This study shows the usefulness of efficient Cr(VI)-reducing bacterial strain SUCR140 in improving yields probably through decreased Cr toxicity and improved symbiotic relationship of the plants with Rhizobium. Further decrease in the translocation of Cr(VI) through improved nodulation by Rhizobium in the presence of efficient Cr-reducing bacterial strains could also decrease the accumulation of Cr in shoots.

Endophytic bacteria in cacti seeds can improve the development of cactus seedlings.

Treesearch

M. Esther Puente; Ching Y. Li; Yoav Bashan

2009-01-01

A plant-bacterium association between the giant cardon cactus Pachycereus pringlei and endophytic bacteria help seedlings establish and grow on barren rock, This cactus, together with other desert plants, is responsible for weathering ancient lava flows in the Baja California Peninsula of Mexico.When cardon seeds are inoculated with endophytic...

Evaluation of feed grade sodium bisulfate impact on gastrointestinal tract microbiota ecology in broilers via a pyrosequencing platform

USDA-ARS?s Scientific Manuscript database

The gastrointestinal microbial community in broiler chicken consists of many different species of bacteria and the overall microbiota can be various from bird to bird. In order to control pathogenic bacteria in broiler and improve gut health, numerous potential dietary amendments such as prebiotics...

Strength and stability of microbial plugs in porous media

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

Sarkar, A.K.; Sharma, M.M.; Georgiou, G.

1995-12-31

Mobility reduction induced by the growth and metabolism of bacteria in high-permeability layers of heterogeneous reservoirs is an economically attractive technique to improve sweep efficiency. This paper describes an experimental study conducted in sandpacks using an injected bacterium to investigate the strength and stability of microbial plugs in porous media. Successful convective transport of bacteria is important for achieving sufficient initial bacteria distribution. The chemotactic and diffusive fluxes are probably not significant even under static conditions. Mobility reduction depends upon the initial cell concentrations and increase in cell mass. For single or multiple static or dynamic growth techniques, permeability reductionmore » was approximately 70% of the original permeability. The stability of these microbial plugs to increases in pressure gradient and changes in cell physiology in a nutrient-depleted environment needs to be improved.« less

Bacteria within the Gastrointestinal Tract Microbiota Correlated with Improved Growth and Feed Conversion: Challenges Presented for the Identification of Performance Enhancing Probiotic Bacteria

PubMed Central

Stanley, Dragana; Hughes, Robert J.; Geier, Mark S.; Moore, Robert J.

2016-01-01

Identification of bacteria associated with desirable productivity outcomes in animals may offer a direct approach to the identification of probiotic bacteria for use in animal production. We performed three controlled chicken trials (n = 96) to investigate caecal microbiota differences between the best and poorest performing birds using four performance measures; feed conversion ratio (FCR), utilization of energy from the feed measured as apparent metabolisable energy, gain rate (GR), and amount of feed eaten (FE). The shifts in microbiota composition associated with the performance measures were very different between the three trials. Analysis of the caecal microbiota revealed that the high and low FCR birds had significant differences in the abundance of some bacteria as demonstrated by shifts in microbiota alpha and beta diversity. Trials 1 and 2 showed significant overall community shifts, however, the microbial changes driving the difference between good and poor performers were very different. Lachnospiraceae, Ruminococcaceae, and Erysipelotrichaceae families and genera Ruminococcus, Faecalibacterium and multiple lineages of genus Clostridium (from families Lachnospiraceae, Ruminococcaceae, and Erysipelotrichaceae) were highly abundant in good FCR birds in Trial 1. Different microbiota was associated with FCR in Trial 2; Catabacteriaceae and unknown Clostridiales family members were increased in good FCR and genera Clostridium (from family Clostridiaceae) and Lactobacillus were associated with poor FCR. Trial 3 had only mild microbiota differences associated with all four performance measures. Overall, the genus Lactobacillus was correlated with feed intake which resulted in poor FCR performance. The genus Faecalibacterium correlated with improved FCR, increased GR and reduced FE. There was overlap in phylotypes correlated with improved FCR and GR, while different microbial cohorts appeared to be correlated with FE. Even under controlled conditions different cohorts of birds developed distinctly different microbiotas. Within the different trial groups the abundance of certain bacterial groups correlated with productivity outcomes. However, with different underlying microbiotas there were different bacteria correlated with performance. The challenge will be to identify probiotic bacteria that can reliably deliver favorable outcomes from diverse microbiotas. PMID:26925052

Factors influencing the removal of antibiotic-resistant bacteria and antibiotic resistance genes by the electrokinetic treatment.

PubMed

Li, Hongna; Li, Binxu; Zhang, Zhiguo; Tian, Yunlong; Ye, Jing; Lv, Xiwu; Zhu, Changxiong

2018-09-30

The performance of the electrokinetic remediation process on the removal of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) was evaluated with different influencing factors. With chlortetracycline (CTC), oxytetracycline (OTC), and tetracycline (TC) as template chemicals, the removal of both ARB and ARGs was enhanced with the increase of voltage gradient (0.4-1.2 V cm -1 ) and prolonged reaction time (3-14 d). The greatest removal (26.01-31.48% for ARB, 37.93-83.10% for ARGs) was obtained applying a voltage of 1.2 V cm -1 , leading to the highest electrical consumption. The effect of polarity reversal intervals on the inactivation ratio of ARB followed the order of 0 h (66.06-80.00%) > 12 h (17.07-24.75%) > 24 h (10.44-13.93%). Lower pH, higher current density, and more evenly-distributed voltage drop was observed with a polarity reversal interval of 12 h compared with that of 24 h, leading to more efficient electrochemical reactions in soil. Compared with sul genes, tet genes were more vulnerable to be attacked in an electric field. It was mainly attributed to the lower abundance of tet genes (except tetM) and the varied effects of electrokinetic remediation process on different ARGs. Moreover, a relatively less removal ratio of tetC and tetG was obtained mainly due to the mechanism of the efflux pump upregulation. Both tet and sul genes were positively correlated with TC-resistant bacteria. The efflux pump genes like tetG and the cellular protection genes like tetM showed different correlations with ARB. This study enhances the current understanding on the removal strategies of ARB and ARGs, and it provides important parameters for their destruction by the electrokinetic treatment. Copyright © 2018 Elsevier Inc. All rights reserved.

Characterization of the efficiency and uncertainty of skimmed milk flocculation for the simultaneous concentration and quantification of water-borne viruses, bacteria and protozoa.

PubMed

Gonzales-Gustavson, Eloy; Cárdenas-Youngs, Yexenia; Calvo, Miquel; da Silva, Marcelle Figueira Marques; Hundesa, Ayalkibet; Amorós, Inmaculada; Moreno, Yolanda; Moreno-Mesonero, Laura; Rosell, Rosa; Ganges, Llilianne; Araujo, Rosa; Girones, Rosina

2017-03-01

In this study, the use of skimmed milk flocculation (SMF) to simultaneously concentrate viruses, bacteria and protozoa was evaluated. We selected strains of faecal indicator bacteria and pathogens, such as Escherichia coli and Helicobacter pylori. The viruses selected were adenovirus (HAdV 35), rotavirus (RoV SA-11), the bacteriophage MS2 and bovine viral diarrhoea virus (BVDV). The protozoa tested were Acanthamoeba, Giardia and Cryptosporidium. The mean recoveries with q(RT)PCR were 66% (HAdV 35), 24% (MS2), 28% (RoV SA-11), 15% (BVDV), 60% (E. coli), 30% (H. pylori) and 21% (Acanthamoeba castellanii). When testing the infectivity, the mean recoveries were 59% (HAdV 35), 12% (MS2), 26% (RoV SA-11) and 0.7% (BVDV). The protozoa Giardia lamblia and Cryptosporidium parvum were studied by immunofluorescence with recoveries of 18% and 13%, respectively. Although q(RT)PCR consistently showed higher quantification values (as expected), q(RT)PCR and the infectivity assays showed similar recoveries for HAdV 35 and RoV SA-11. Additionally, we investigated modelling the variability and uncertainty of the recovery with this method to extrapolate the quantification obtained by q(RT)PCR and estimate the real concentration. The 95% prediction intervals of the real concentration of the microorganisms inoculated were calculated using a general non-parametric bootstrap procedure adapted in our context to estimate the technical error of the measurements. SMF shows recoveries with a low variability that permits the use of a mathematical approximation to predict the concentration of the pathogen and indicator with acceptable low intervals. The values of uncertainty may be used for a quantitative microbial risk analysis or diagnostic purposes. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Interval Running Training Improves Cognitive Flexibility and Aerobic Power of Young Healthy Adults.

PubMed

Venckunas, Tomas; Snieckus, Audrius; Trinkunas, Eugenijus; Baranauskiene, Neringa; Solianik, Rima; Juodsnukis, Antanas; Streckis, Vytautas; Kamandulis, Sigitas

2016-08-01

Venckunas, T, Snieckus, A, Trinkunas, E, Baranauskiene, N, Solianik, R, Juodsnukis, A, Streckis, V, and Kamandulis, S. Interval running training improves cognitive flexibility and aerobic power of young healthy adults. J Strength Cond Res 30(8): 2114-2121, 2016-The benefits of regular physical exercise may well extend beyond the reduction of chronic diseases risk and augmentation of working capacity, to many other aspects of human well-being, including improved cognitive functioning. Although the effects of moderate intensity continuous training on cognitive performance are relatively well studied, the benefits of interval training have not been investigated in this respect so far. The aim of the current study was to assess whether 7 weeks of interval running training is effective at improving both aerobic fitness and cognitive performance. For this purpose, 8 young dinghy sailors (6 boys and 2 girls) completed the interval running program with 200 m and 2,000 m running performance, cycling maximal oxygen uptake, and cognitive function was measured before and after the intervention. The control group consisted of healthy age-matched subjects (8 boys and 2 girls) who continued their active lifestyle and were tested in the same way as the experimental group, but did not complete any regular training. In the experimental group, 200 m and 2,000 m running performance and cycling maximal oxygen uptake increased together with improved results on cognitive flexibility tasks. No changes in the results of short-term and working memory tasks were observed in the experimental group, and no changes in any of the measured indices were evident in the controls. In conclusion, 7 weeks of interval running training improved running performance and cycling aerobic power, and were sufficient to improve the ability to adjust behavior to changing demands in young active individuals.

Effect of different packaging materials containing poly-[2-(tert-butylamino) methylstyrene] on the growth of spoilage and pathogenic bacteria on fresh meat.

PubMed

Dohlen, S; Braun, C; Brodkorb, F; Fischer, B; Ilg, Y; Kalbfleisch, K; Lorenz, R; Kreyenschmidt, M; Kreyenschmidt, J

2017-09-18

The objective of this study was to investigate the effect of novel antimicrobial packaging materials containing poly-[2-(tertbutylamino) methylstyrene] (poly(TBAMS)) on the growth of typical spoilage and pathogenic bacteria present on meat. The antimicrobial activity of materials containing different poly(TBAMS) concentrations was determined by comparing the bacterial counts on reference and sample materials at different temperatures and times and in the presence of meat components. Storage tests with poultry fillets and veal cutlets were conducted with samples vacuum packaged in the reference foil and foil containing 10% poly(TBAMS). After specific time intervals, typical spoilage microorganisms, total viable count (TVC), sensory changes and pH value were analysed. The results of the different poly(TBAMS) containing packaging materials showed an increase of the antimicrobial activity with an increasing amount of poly(TBAMS) in the base polymer. A high antimicrobial activity against inoculum of spoilage and pathogenic organisms typical for meat products was detected of a multilayer foil containing 10% poly(TBAMS) in the inner layer after 24h at 7°C. Gram positive-bacteria were more sensitive to poly(TBAMS) foil than gram-negative bacteria. In storage tests however, over the entire storage, a significant effect of this poly(TBAMS) foil on microbial growth on chicken breast fillets and veal cutlets could not be identified. Poly(TBAMS) packaging materials showed very good antimicrobial properties against a wide range of bacteria. However, for a significant inhibition of microbial growth on fresh meat, a higher amount of poly(TBAMS) was necessary to prolong the shelf life of meat. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of photodynamic therapy on pathogenic bacteria around peri-implant sulcus and in the cavity between abutment and implant after healing phase: A prospective clinical study.

PubMed

Zhou, Lin-Yi; Shi, Jun-Yu; Zhu, Yu; Qian, Shu-Jiao; Lai, Hong-Chang; Gu, Ying-Xin

2018-05-14

To compare levels of pathogens from peri-implant sulcus versus abutment screw cavities after photodynamic therapy. Twenty patients were included. Photodynamic therapy (PDT) was applied both in sulcus and cavities after sampling following suprastructures loading, and repeated after 2 weeks. Two samples each containing four paper points were collected for each implant at baseline, 2 weeks, 3 months: (i) peri-implant sulcus and (ii) abutment screw cavities. Seventy-five percent ethanol was applied in another 20 patients as the control group in the same way. qPCR was used to quantify periodontal pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus mutans. PDT showed a better bacterial reduction than ethanol. P. g. and F. n. were most frequently detected, while less for S. m. P. gingivalis' proportion from both sites was significantly higher than the other two bacteria (P < 0.05), except for 2 weeks' peri-implant sulcus sample. Bacteria counts from abutment screw cavities were always less than those from peri-implant sulcus and was significantly lower for total bacteria at 3 months (P < 0.05). Total bacterial from abutment screw cavities significantly reduced at 3 months compared to baseline (P < 0.05). PDT appears to be effective in bacterial reduction compared to ethanol and can reduce P. gingivalis with short time intervals, as well as decreasing total bacteria counts within abutment screw cavities in the long run, suggesting PDT an effective way sterilizing inner surface of oral implant suprastrutures. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

[The effects of electromagnetic radiation of extremely high frequency and low intensity on the growth rate of bacteria Escherichia coli and the role of medium pH].

PubMed

Tadevosian, A; Kalantarian, V; Trchunian, A

2007-01-01

It has been shown that coherent electromagnetic irradiation (EMI) of extremely high frequency (45-53 GHz) or millimeter waves (wavelength 5.6-6.7 mm) of low intensity (flux capacity 0.06 mW/cm2) of Escherichia coli K12, grown under anaerobic conditions during the fermentation of sugar (glucose) for 30 min or 1 h, caused a decrease in their growth rate, the maximum inhibitory effect being achieved at a frequency of 51.8 or 53 GHz. This effect depended on medium pH when the maximal action was determined at pH 7.5. In addition, separate 30-min of 1-h irradiation (frequency 51.8 or 53 GHz) of doubly distilled water or some inorganic ions contained in Tris-phosphate buffer where the cells were transferred induced oppositely directed changes in further growth of these bacteria under anaerobic conditions; irradiation of water caused a decrease in the growth rate of bacteria. A significant change in pH of water (0.5-1.5 unit) was induced by a 30-irradiation at a frequency of 49, 50.3, 51.8, or 53 GHz, when the initial pH value was 6.0 or 8.0, but not 7.5. These results indicate the changes in the properties of water and its role in the effects of EMI of extremely high frequency. The marked effect of EMI on bacteria disappeared upon repeated irradiation for 1 h at a frequency of 51.8 or 53 GHz with an interval of 2 hours. This result indicates some compensatory mechanisms in bacteria.

Fecal-indicator bacteria concentrations in the Illinois River between Hennepin and Peoria, Illinois: 2007-08

USGS Publications Warehouse

Dupre, David H.; Hortness, Jon E.; Terrio, Paul J.; Sharpe, Jennifer B.

2012-01-01

The Illinois Environmental Protection Agency has designated portions of the Illinois River in Peoria, Woodford, and Tazewell Counties, Illinois, as impaired owing to the presence of fecal coliform bacteria. The U.S. Geological Survey, in cooperation with the Tri-County Regional Planning Commission, examined the water quality in the Illinois River and major tributaries within a 47-mile reach between Peoria and Hennepin, Ill., during water year 2008 (October 2007–September 2008). Investigations included synoptic (snapshot) sampling at multiple locations in a 1-day period: once in October 2007 during lower streamflow conditions, and again in June 2008 during higher streamflow conditions. Five locations in the study area were monitored for the entire year at monthly or more frequent intervals. Two indicator bacteria were analyzed in each water sample: fecal coliform and Escherichia coli (E. coli). Streamflow information from previously established monitoring locations in the study area was used in the analysis. Correlation analyses were used to characterize the relation between the two fecal-indicator bacteria and the relation of either indicator to streamflow. Concentrations of the two measured fecal-indicator bacteria correlated well for all samples analyzed (r = 0.94, p E. coli: rho = -0.43, p = 0.0157). The correlation between fecal indicators and streamflow in tributaries or in the Illinois River at Hennepin was found to be statistically significant, yet moderate in strength with coefficient values ranging from r = 0.4 to 0.6. Indirect observations from the June 2008 higher flow synoptic event may indicate continued effects from combined storm and sanitary sewers in the vicinity of the Illinois River near Peoria, Ill., contributing to observed single-sample exceedance of the State criterion for fecal coliform.

Influence of heat inactivation of human serum on the opsonization of Streptococcus mutans.

PubMed

Moore, M A; Hakki, Z W; Gregory, R L; Gfell, L E; Kim-Park, W K; Kowolik, M J

1997-12-15

Phagocytosis of bacteria, such as Streptococcus mutans, is important to host defense. One mechanism by which phagocytosis can be enhanced is by antibody or complement-mediated opsonization of bacteria. Many studies utilize opsonization of bacteria to enhance a cellular response, but little information has been found examining methodology or validity of the opsonization process following the denaturization of the serum. Human serum was inactivated by heat in order to disrupt the classical and alternative pathways of the complement cascade. S. mutans isolated from human subjects were opsonized with heat-inactivated human serum before exposing them to viable neutrophils in vitro. Luminol-dependent chemiluminescence (CL) was used to measure neutrophil activation. Human serum used to opsonize the bacteria was denatured by incubation at 57 degrees C for intervals of 30 and 60 min to inactivate complement. The results from the opsonization data indicated that there was significantly increased CL with 60-min inactivation of the serum (34% increase in mean integration mV.min; p < or = 0.05) over the nonopsonized control. This indicated a successful opsonization of the bacteria. In addition, the data demonstrate that the inactivation of serum requires a minimum of 60 min at 57 degrees C to disrupt the complement cascade, while 30- and 15-min inactivations produced no significant increase in CL activity over the control. Standard sandwich ELISA assays, detecting complement binding to S. mutans, confirmed successful heat inactivation of serum showing a significant decrease (p < or = 0.001) in complement binding to S. mutans after 30 min, but could not explain the increased CL response after 60-min heat deactivation of the serum.

Risk factors for infection and/or colonisation with extended-spectrum β-lactamase-producing bacteria in the neonatal intensive care unit: a meta-analysis.

PubMed

Li, Xuan; Xu, Xuan; Yang, Xianxian; Luo, Mei; Liu, Pin; Su, Kewen; Qing, Ying; Chen, Shuai; Qiu, Jingfu; Li, Yingli

2017-11-01

Extended-spectrum β-lactamase (ESBL)-producing bacteria are an important cause of healthcare-associated infections in the neonatal intensive care unit (NICU). The aim of this meta-analysis was to identify risk factors associated with infection and/or colonisation with ESBL-producing bacteria in the NICU. Electronic databases were searched for relevant studies published from 1 January 2000 to 1 July 2016. The literature was screened and data were extracted according to the inclusion and exclusion criteria. The Z-test was used to calculate the pooled odds ratio (OR) of the risk factors. ORs and their 95% confidence intervals were used to determine the significance of the risk. A total of 14 studies, including 746 cases and 1257 controls, were identified. Thirteen risk factors were determined to be related to infection and/or colonisation with ESBL-producing bacteria in the NICU: birthweight [standardised mean difference (SMD) = 1.17]; gestational age (SMD = 1.36); Caesarean delivery (OR = 1.76); parenteral nutrition (OR = 7.51); length of stay in the NICU (SMD = 0.72); mechanical ventilation (OR = 4.8); central venous catheter use (OR = 2.85); continuous positive airway pressure (OR = 5.0); endotracheal intubation (OR = 2.82); malformations (OR = 2.89); previous antibiotic use (OR = 6.72); ampicillin/gentamicin (OR = 2.31); and cephalosporins (OR = 6.0). This study identified risk factors for infection and/or colonisation with ESBL-producing bacteria in the NICU, which may provide a theoretical basis for preventive measures and targeted interventions. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Airborne environmental endotoxin: a cross-validation of sampling and analysis techniques.

PubMed Central

Walters, M; Milton, D; Larsson, L; Ford, T

1994-01-01

A standard method for measurement of airborne environmental endotoxin was developed and field tested in a fiberglass insulation-manufacturing facility. This method involved sampling with a capillary-pore membrane filter, extraction in buffer using a sonication bath, and analysis by the kinetic-Limulus assay with resistant-parallel-line estimation (KLARE). Cross-validation of the extraction and assay method was performed by comparison with methanolysis of samples followed by 3-hydroxy fatty acid (3-OHFA) analysis by gas chromatography-mass spectrometry. Direct methanolysis of filter samples and methanolysis of buffer extracts of the filters yielded similar 3-OHFA content (P = 0.72); the average difference was 2.1%. Analysis of buffer extracts for endotoxin content by the KLARE method and by gas chromatography-mass spectrometry for 3-OHFA content produced similar results (P = 0.23); the average difference was 0.88%. The source of endotoxin was gram-negative bacteria growing in recycled washwater used to clean the insulation-manufacturing equipment. The endotoxin and bacteria become airborne during spray cleaning operations. The types of 3-OHFAs in bacteria cultured from the washwater, present in the washwater and in the air, were similar. Virtually all of the bacteria cultured from air and water were gram negative composed mostly of two species, Deleya aesta and Acinetobacter johnsonii. Airborne countable bacteria correlated well with endotoxin (r2 = 0.64). Replicate sampling showed that results with the standard sampling, extraction, and Limulus assay by the KLARE method were highly reproducible (95% confidence interval for endotoxin measurement +/- 0.28 log10). These results demonstrate the accuracy, precision, and sensitivity of the standard procedure proposed for airborne environmental endotoxin. PMID:8161191

Relationship between serologic markers of periodontal bacteria and metabolic syndrome and its components.

PubMed

Shrestha, Deepika; Choi, Youn-Hee; Zhang, Jiajia; Hazlett, Linda J; Merchant, Anwar T

2015-03-01

Periodontitis is a result of a complex biologic alteration of the periodontal microenvironment and a distributional shift of key periodontal pathogens. Metabolic syndrome (MetS), a complex cluster of cardiovascular risk factors, has been linked to periodontal diseases; however, the contribution of periodontal bacteria to systemic conditions remains unclear. The study population comprised 7,848 United States adults who participated in an interview, underwent a clinical oral-health examination, and had serum immunoglobulin G titers measured against 19 periodontal bacteria as part of the third National Health and Nutritional Examination Survey. The z-score antibody titers were clustered into four mutually exclusive groups and named after Socransky's classification of periodontal bacteria (Orange-Red, Red-Green, Yellow-Orange, and Orange-Blue). Survey logistic regression was used to investigate the independent associations between the cluster scores, and MetS and each component, including hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol, central obesity, and elevated fasting glucose. The Orange-Red cluster score (that included Porphyromonas gingivalis and Prevotella spp.) was positively associated (odds ratio [OR] = 1.067, 95% confidence interval [CI] = 1.02 to 1.12) and the Orange-Blue cluster score (which included Actinomyces naeslundii and Eubacterium nodatum) was inversely associated (OR = 0.93, 95% CI = 0.88 to 0.97) with elevated fasting glucose (≥ 110 mg/dL) after adjustment for clusters and potential confounders. Neither MetS nor its other remaining MetS components were associated with a particular cluster score. The associations between specific antibody clusters (Orange-Red and Orange-Blue) against periodontal bacteria and elevated plasma glucose were in qualitatively opposite directions after multivariable adjustment in a large, adult population. The periodontal bacterial profile was not found to be associated with metabolic control other than a very moderate association with elevated plasma glucose.

[Effect of antagonistic bacteria and soil disinfectant on soil bacterium community in banana Fusarium wilt disease area].

PubMed

Zhou, Dengbo; Jing, Tao; Tan, Xin; Chen, Bo; Zhang, Xiyan; Gao, Zhufen

2013-08-04

The objective of the present study is to elucidate the effects of the application of cake fertilizer fermentation fluid with antagonistic bacteria and soil disinfectant chlorine dioxide on the occurrence of banana fusarium wilt disease and soil bacterium community. Under the field cultivation conditions, the Biolog and T-RFLP method was used to investigate the soil bacterium diversity and community features in different treatments at different periods. The results show that both cake fertilizer fermentation fluid with antagonistic bacteria and soil disinfectant could reduce disease index of banana fusarium wilt disease significantly, the highest control effect could reach 60.82% with the combined application of these two methods. The result of Biolog eco plate shows that the application of cake fertilizer fermentation fluid with antagonistic bacteria could improve soil microbial AWCD (average well color development) and population uniformity, the use of soil disinfectant significantly reduced the soil microbial population's abundance and the uniformity. Principal component analysis shows that the soil microbial population using carbon source had an increasing trend throughout the banana growing season, the main carbon sources in the early stage were amino acids, carboxylic acids, amphiphilic compounds and carbohydrates, and the increased main carbon sources in the later stage were carboxylic acids and amphiphilic compounds. Soil bacterial diversity analysis by T-RFLP shows that the treatments of cake fertilizer fermentation fluid with antagonistic bacteria had the highest bacterial TRFs (Terminal restriction fragment) fragments, which resulted from the increase of Flavobacterium, Pseudomona and Lactobacillus population in the soil. The application of cake fertilizer fermentation fluid with antagonistic bacteria combining soil disinfectant could increase antagonistic microorganisms species, enhance soil microbial diversity, improve soil microbial ecological structure on the basis of reducing pathogen in soil, finally achieve the goal of improving the control effects of banana fusarium wilt disease.

Alendronate-coated long-circulating liposomes containing 99mtechnetium-ceftizoxime used to identify osteomyelitis

PubMed Central

Ferreira, Diego dos Santos; Boratto, Fernanda Alves; Cardoso, Valbert Nascimento; Serakides, Rogéria; Fernandes, Simone Odília; Ferreira, Lucas Antônio Miranda; Oliveira, Mônica Cristina

2015-01-01

Osteomyelitis is a progressive destruction of bones caused by microorganisms. Inadequate or absent treatment increases the risk of bone growth inhibition, fractures, and sepsis. Among the diagnostic techniques, functional images are the most sensitive in detecting osteomyelitis in its early stages. However, these techniques do not have adequate specificity. By contrast, radiolabeled antibiotics could improve selectivity, since they are specifically recognized by the bacteria. The incorporation of these radiopharmaceuticals in drug-delivery systems with high affinity for bones could improve the overall uptake. In this work, long-circulating and alendronate-coated liposomes containing 99mtechnetium-radiolabeled ceftizoxime were prepared and their ability to identify infectious foci (osteomyelitis) in animal models was evaluated. The effect of the presence of PEGylated lipids and surface-attached alendronate was evaluated. The bone-targeted long-circulating liposomal 99mtechnetium–ceftizoxime showed higher uptake in regions of septic inflammation than did the non-long-circulating and/or alendronate-non-coated liposomes, showing that both the presence of PEGylated lipids and alendronate coating are important to optimize the bone targeting. Scintigraphic images of septic or aseptic inflammation-bearing Wistar rats, as well as healthy rats, were acquired at different time intervals after the intravenous administration of these liposomes. The target-to-non-target ratio proved to be significantly higher in the osteomyelitis-bearing animals for all investigated time intervals. Biodistribution studies were also performed after the intravenous administration of the formulation in osteomyelitis-bearing animals. A significant amount of liposomes were taken up by the organs of the mononuclear phagocyte system (liver and spleen). Intense renal excretion was also observed during the entire experiment period. Moreover, the liposome uptake by the infectious focus was significantly high. These results show that long-circulating and alendronate-coated liposomes containing 99mtechnetium-radiolabeled ceftizoxime have a tropism for infectious foci. PMID:25848262

An Element of Determinism in a Stochastic Flagellar Motor Switch

PubMed Central

Xie, Li; Altindal, Tuba; Wu, Xiao-Lun

2015-01-01

Marine bacterium Vibrio alginolyticus uses a single polar flagellum to navigate in an aqueous environment. Similar to Escherichia coli cells, the polar flagellar motor has two states; when the motor is counter-clockwise, the cell swims forward and when the motor is clockwise, the cell swims backward. V. alginolyticus also incorporates a direction randomization step at the start of the forward swimming interval by flicking its flagellum. To gain an understanding on how the polar flagellar motor switch is regulated, distributions of the forward Δf and backward Δb intervals are investigated herein. We found that the steady-state probability density functions, P(Δf) and P(Δb), of freely swimming bacteria are strongly peaked at a finite time, suggesting that the motor switch is not Poissonian. The short-time inhibition is sufficiently strong and long lasting, i.e., several hundred milliseconds for both intervals, which is readily observed and characterized. Treating motor reversal dynamics as a first-passage problem, which results from conformation fluctuations of the motor switch, we calculated P(Δf) and P(Δb) and found good agreement with the measurements. PMID:26554590

An Element of Determinism in a Stochastic Flagellar Motor Switch.

PubMed

Xie, Li; Altindal, Tuba; Wu, Xiao-Lun

2015-01-01

Marine bacterium Vibrio alginolyticus uses a single polar flagellum to navigate in an aqueous environment. Similar to Escherichia coli cells, the polar flagellar motor has two states; when the motor is counter-clockwise, the cell swims forward and when the motor is clockwise, the cell swims backward. V. alginolyticus also incorporates a direction randomization step at the start of the forward swimming interval by flicking its flagellum. To gain an understanding on how the polar flagellar motor switch is regulated, distributions of the forward Δf and backward Δb intervals are investigated herein. We found that the steady-state probability density functions, P(Δf) and P(Δb), of freely swimming bacteria are strongly peaked at a finite time, suggesting that the motor switch is not Poissonian. The short-time inhibition is sufficiently strong and long lasting, i.e., several hundred milliseconds for both intervals, which is readily observed and characterized. Treating motor reversal dynamics as a first-passage problem, which results from conformation fluctuations of the motor switch, we calculated P(Δf) and P(Δb) and found good agreement with the measurements.

New Trends in Impedimetric Biosensors for the Detection of Foodborne Pathogenic Bacteria

PubMed Central

Wang, Yixian; Ye, Zunzhong; Ying, Yibin

2012-01-01

The development of a rapid, sensitive, specific method for the foodborne pathogenic bacteria detection is of great importance to ensure food safety and security. In recent years impedimetric biosensors which integrate biological recognition technology and impedance have gained widespread application in the field of bacteria detection. This paper presents an overview on the progress and application of impedimetric biosensors for detection of foodborne pathogenic bacteria, particularly the new trends in the past few years, including the new specific bio-recognition elements such as bacteriophage and lectin, the use of nanomaterials and microfluidics techniques. The applications of these new materials or techniques have provided unprecedented opportunities for the development of high-performance impedance bacteria biosensors. The significant developments of impedimetric biosensors for bacteria detection in the last five years have been reviewed according to the classification of with or without specific bio-recognition element. In addition, some microfluidics systems, which were used in the construction of impedimetric biosensors to improve analytical performance, are introduced in this review. PMID:22737018

Extracellular polymeric substances govern the development of biofilm and mass transfer of polycyclic aromatic hydrocarbons for improved biodegradation.

PubMed

Zhang, Yinping; Wang, Fang; Zhu, Xiaoshu; Zeng, Jun; Zhao, Qiguo; Jiang, Xin

2015-10-01

The hypothesis that extracellular polymeric substances (EPS) affect the formation of biofilms for subsequent enhanced biodegradation of polycyclic aromatic hydrocarbons was tested. Controlled formation of biofilms on humin particles and biodegradation of phenanthrene and pyrene were performed with bacteria and EPS-extracted bacteria of Micrococcus sp. PHE9 and Mycobacterium sp. NJS-P. Bacteria without EPS extraction developed biofilms on humin, in contrast the EPS-extracted bacteria could not attach to humin particles. In the subsequent biodegradation of phenanthrene and pyrene, the biodegradation rates by biofilms were significantly higher than those of EPS-extracted bacteria. Although, both the biofilms and EPS-extracted bacteria showed increases in EPS contents, only the EPS contents in biofilms displayed significant correlations with the biodegradation efficiencies of phenanthrene and pyrene. It is proposed that the bacterial-produced EPS was a key factor to mediate bacterial attachment to other surfaces and develop biofilms, thereby increasing the bioavailability of poorly soluble PAH for enhanced biodegradation. Copyright © 2015. Published by Elsevier Ltd.

Optimization of isolation and cultivation of bacterial endophytes through addition of plant extract to nutrient media

PubMed Central

Eevers, N; Gielen, M; Sánchez-López, A; Jaspers, S; White, J C; Vangronsveld, J; Weyens, N

2015-01-01

Many endophytes have beneficial effects on plants and can be exploited in biotechnological applications. Studies hypothesize that only 0.001–1% of all plant-associated bacteria are cultivable. Moreover, even after successful isolations, many endophytic bacteria often show reduced regrowth capacity. This research aimed to optimize isolation processes and culturing these bacteria afterwards. We compared several minimal and complex media in a screening. Beside the media themselves, two gelling agents and adding plant extract to media were investigated to enhance the number and diversity of endophytes as well as the growth capacity when regrown after isolation. In this work, 869 medium delivered the highest numbers of cultivable bacteria, as well as the highest diversity. When comparing gelling agents, no differences were observed in the numbers of bacteria. Adding plant extract to the media lead to a slight increase in diversity. However, when adding plant extract to improve the regrowth capacity, sharp increases of viable bacteria occurred in both rich and minimal media. PMID:25997013

Brief ultrasonication improves detection of biofilm-formative bacteria around a metal implant.

PubMed

Kobayashi, Naomi; Bauer, Thomas W; Tuohy, Marion J; Fujishiro, Takaaki; Procop, Gary W

2007-04-01

Biofilms are complex microenvironments produced by microorganisms on surfaces. Ultrasonication disrupts biofilms and may make the microorganism or its DNA available for detection. We determined whether ultrasonication could affect our ability to detect bacteria adherent to a metal substrate. A biofilm-formative Staphylococcus aureus strain was used for an in vitro implant infection model (biofilm-formative condition). We used quantitative culture and real time-polymerase chain reaction to determine the influence of different durations of ultrasound on bacterial adherence and viability. Sonication for 1 minute increased the yield of bacteria. Sonication longer than 5 minutes led to fewer bacterial colonies by conventional culture but not by polymerase chain reaction. This suggests short periods of sonication help release bacteria from the metal substrate by disrupting the biofilm, but longer periods of sonication lyse bacteria prohibiting their detection in microbiologic cultures. A relatively short duration of sonication may be desirable for maximizing detection of biofilm-formative bacteria around implants by culture or polymerase chain reaction.

Multicenter Evaluation of the Bruker MALDI Biotyper CA System for the Identification of Clinically Important Bacteria and Yeasts.

PubMed

Wilson, Deborah A; Young, Stephen; Timm, Karen; Novak-Weekley, Susan; Marlowe, Elizabeth M; Madisen, Neil; Lillie, Jennifer L; Ledeboer, Nathan A; Smith, Rebecca; Hyke, Josh; Griego-Fullbright, Christen; Jim, Patricia; Granato, Paul A; Faron, Matthew L; Cumpio, Joven; Buchan, Blake W; Procop, Gary W

2017-06-01

A report on the multicenter evaluation of the Bruker MALDI Biotyper CA System (MBT-CA; Bruker Daltonics, Billerica, MA) for the identification of clinically important bacteria and yeasts. In total, 4,399 isolates of medically important bacteria and yeasts were assessed in the MBT-CA. These included 2,262 aerobic gram-positive (AGP) bacteria, 792 aerobic gram-negative (AGN) bacteria 530 anaerobic (AnA) bacteria, and 815 yeasts (YSTs). Three processing methods were assesed. Overall, 98.4% (4,329/4,399) of all bacterial and yeast isolates were correctly identified to the genus and species/species complex level, and 95.7% of isolates were identified with a high degree of confidence. The percentage correctly identified and the percentage identified correctly with a high level of confidence, respectively, were as follows: AGP bacteria (98.6%/96.5%), AGN bacteria (98.5%/96.8%), AnA bacteria (98.5%/97.4%), and YSTs (97.8%/87.6%). The extended direct transfer method was only minimally superior to the direct transfer method for bacteria (89.9% vs 86.8%, respectively) but significantly superior for yeast isolates (74.0% vs 48.9%, respectively). The Bruker MALDI Biotyper CA System accurately identifies most clinically important bacteria and yeasts and has optional processing methods to improve isolate characterization. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Flies and their bacterial loads in greyhound dog kennels in Kansas.

PubMed

Urban, J E; Broce, A

1998-03-01

Breeders of greyhound dogs traditionally feed racing animals and nursing bitches raw meat, and that meat generally is obtained frozen from commercial renderers. Previous studies have shown that the rendered meat is frequently contaminated with enteric bacteria, including Salmonella spp., and that during thawing the rendered meat is exposed to filth flies common in dog kennels. Nursing greyhound pups tend to experience a high morbidity and mortality from intestinal infections, and we attempted to determine in this study whether enterics could be spread to pups through contaminated flies. At intervals during 1995 and 1996, flies were trapped or were net-collected from 10 dog breeding kennels in the region around Abilene, KS. Trapped flies were identified and counted to determine population numbers, and netted flies were cultured in tetrathionate broth and streaked to medium selecting for Salmonella sp. and other lactose-negative Gram (-) bacteria. The relative numbers of different fly species varied with the sampling method, but traps and sweep nets produced similar proportions of the different fly species. Blow flies were twice as likely to be contaminated with enteric bacteria as any other fly. The most common enteric bacteria found were Proteus spp., followed by Providencia spp., Pseudomonas spp., and Salmonella spp. The incidence of Salmonella and Proteus spp. seemed to correlate more with accessibility of flies to dog excrement than to rendered meat. The apparent high incidence of enteric contamination of filth flies clearly implicates them as vectors of enteric diseases in kennels.

Diversity of Fungi, Bacteria, and Actinomycetes on Leaves Decomposing in a Stream▿

PubMed Central

Das, Mitali; Royer, Todd V.; Leff, Laura G.

2007-01-01

Although fungi, bacteria, and specific bacterial taxa, such as the actinomycetes, have been studied extensively in various habitats, few studies have examined them simultaneously, especially on decomposing leaves in streams. In this study, sugar maple and white oak leaves were incubated in a stream in northeastern Ohio for 181 days during which samples were collected at regular intervals. Following DNA extraction, PCR-denaturing gradient gel electrophoresis (DGGE) was performed using fungus-, bacterium-, and actinomycete-specific primers. In addition, fungal and bacterial biomass was estimated. Fungal biomass differed on different days but not between leaves of the two species and was always greater than bacterial biomass. There were significant differences in bacterial biomass through time and between leaf types on some days. Generally, on the basis of DGGE, few differences in community structure were found for different leaf types. However, the ribotype richness of fungi was significantly greater than those of the bacteria and actinomycetes, which were similar to each other. Ribotype richness decreased toward the end of the study for each group except bacteria. Lack of differences between the two leaf types suggests that the microorganisms colonizing the leaf biofilm were primarily generalists that could exploit the resources of the leaves of either species equally well. Thus, we conclude that factors, such as the ecological role of the taxa (generalists versus specialists), stage of decay, and time of exposure, appeared to be more important determinants of microbial community structure than leaf quality. PMID:17142366

Treatment with activated water by GlidArc technology of bacteria producing Biofouling

NASA Astrophysics Data System (ADS)

Hnatiuc, B.; Ghita, S.; Sabau, A.; Hnatiuc, M.; Dumitrache, C. L.; Wartel, M.

2015-02-01

Corrosion in marine environment is an actual problem, being a complex dynamic process influenced mainly by physical, chemical, microbiological and mechanical parameters. Around 70% of the maintenance costs of a ship are associated with the corrosion protection. Times for maintenance related to this phenomenon are greater than 80% of the total repair. Reducing this cost would be a significant saving, and an effective treatment can reduce times related to ships repairing. Biofouling is a main cause of corrosion and for its reduction different methods could be applied, especially in the first part of its production. The atmospheric pressure non-thermal plasmas have been gaining an ever increasing interest for different biodecontamination applications and present potential utilisation in the control of biofouling and biodeterioration. They have a high efficiency of the antimicrobial treatment, including capacity to eradicate microbial biofilms. The adhesion microbial biofilm is mainly influenced by presence of bacteria from the liquid environment. That is why this work concerns the study of annihilation of maximum amount of bacteria from sea water, by using GlidArc technology that produces non-thermal plasma. Bacteria suspended in sea water are placed in contact with activated water. This water is activated by using GlidArc working in humid air. Experimental results refer to the number of different activated and inactivated marine organisms and their evolution, present in solution at certain time intervals after mixing different amounts of seawater with plasma activated water.

Isotopic Signature of the Ancient Biosphere

NASA Technical Reports Server (NTRS)

DesMarais, D. J.; Chang, Sherwood (Technical Monitor)

1997-01-01

The age distribution of 261 field localities, sampled for their well-preserved Archean and Proterozoic sedimentary rocks, revealed a 500-700 Ma episodicity. Assuming that the numbers of sites are a proxy for mass of sediments, the record of well-preserved sediments is more abundant in the intervals 3.5-3.3, 2.8-2.5, 2.1-1.8, 1.5-1.3, and 1.0-0.54 Ga than in the intervening intervals. It is proposed that the crustal inventory of photosynthetic organic carbon was modulated by the volume of sedimentation in sites favorable for the burial and long-term preservation of organic carbon. Tectonic processes controlled this sediment volume. Episodic increases in the organic inventory led to stepwise increases in oxidized reservoirs (e.g., O2, SO4(2-), Fe(3+). The interval 2.9-2.5 Ga recorded a large rise in seawater Sr-87/Sr-86, the oldest-known extensive banded iron formations, and the first evidence (C-13-depleted kerogens) of O2 use by methylotrophic bacteria. The interval 2.2-1.8 Ga has both carbon isotopic evidence for a stepwise increase in the organic reservoir and also paleosol evidence for an O2 increase. The interval 1.1-0.6 Ga shows isotopic evidence for another organic carbon increase. The interval 1.5-1.3 Ga revealed no such increases as yet, perhaps because incomplete rifting of the mid-Proterozoic supercontinent was associated with extensive sedimentation in oxidized continental basins, producing redbeds, coarse clastics, etc. Such sedimentation did not promote the burial of reduced carbon.

Prevalence, codetection and seasonal distribution of upper airway viruses and bacteria in children with acute respiratory illnesses with cough as a symptom.

PubMed

O'Grady, K F; Grimwood, K; Sloots, T P; Whiley, D M; Acworth, J P; Phillips, N; Goyal, V; Chang, A B

2016-06-01

Most studies exploring the role of upper airway viruses and bacteria in paediatric acute respiratory infections (ARI) focus on specific clinical diagnoses and/or do not account for virus-bacteria interactions. We aimed to describe the frequency and predictors of virus and bacteria codetection in children with ARI and cough, irrespective of clinical diagnosis. Bilateral nasal swabs, demographic, clinical and risk factor data were collected at enrollment in children aged <15 years presenting to an emergency department with an ARI and where cough was a symptom. Swabs were tested by polymerase chain reaction for 17 respiratory viruses and seven respiratory bacteria. Logistic regression was used to investigate associations between child characteristics and codetection of the organisms of interest. Between December 2011 and August 2014, swabs were collected from 817 (93.3%) of 876 enrolled children, median age 27.7 months (interquartile range 13.9-60.3 months). Overall, 740 (90.6%) of 817 specimens were positive for any organism. Both viruses and bacteria were detected in 423 specimens (51.8%). Factors associated with codetection were age (adjusted odds ratio (aOR) for age <12 months = 4.9, 95% confidence interval (CI) 3.0, 7.9; age 12 to <24 months = 6.0, 95% CI 3.7, 9.8; age 24 to <60 months = 2.4, 95% CI 1.5, 3.9), male gender (aOR 1.46; 95% CI 1.1, 2.0), child care attendance (aOR 2.0; 95% CI 1.4, 2.8) and winter enrollment (aOR 2.0; 95% CI 1.3, 3.0). Haemophilus influenzae dominated the virus-bacteria pairs. Virus-H. influenzae interactions in ARI should be investigated further, especially as the contribution of nontypeable H. influenzae to acute and chronic respiratory diseases is being increasingly recognized. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Lactic Acid Bateria - Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol

USDA-ARS?s Scientific Manuscript database

Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating alpha-(1,6) and alpha-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, improved strains f...

Recommendations for improved use of the murine TNBS-induced colitis model in evaluating anti-inflammatory properties of lactic acid bacteria: technical and microbiological aspects.

PubMed

Foligné, Benoit; Nutten, Sophie; Steidler, Lothar; Dennin, Véronique; Goudercourt, Denise; Mercenier, Annick; Pot, Bruno

2006-02-01

Probiotic bacteria have been shown to exert promising beneficial effects in different types of intestinal disorders, including chronic inflammation. In this context, animal models of inflammatory bowel disease are useful in studying the possible prophylactic role of candidate probiotic strains. This study aimed at evaluating the critical technological and microbiological parameters as well as the robustness of the murine trinitrobenzene sulfonic acid (TNBS)-induced model of colitis, after intragastric administration of lactic acid bacteria (LAB) preparations. A standardized methodology was applied to assess the protective effect achieved by various bacterial concentrations and culture conditions of the reference strain Lactobacillus plantarum NCIMB 8826. Not only was protection found to vary in function in different levels of colitis, but also repeated experiments showed a clear bacterial dose-dependent attenuation of colitis. The physiological stage of bacteria was shown to impact as well, with substantial, mild, or reduced improvement of inflammatory scores for exponentially growing, stationary-phase, or killed bacteria, respectively. A recombinant strain, secreting murine interleukin-10 (IL-10) and previously reported to successfully treat colitis in two different models of murine colitis (dextran sulfate sodium [DSS] and IL-10-deficient mice), was used to validate the final experimental conditions. In conclusion, we identified and optimized some of the key parameters that need to be controlled in order to ensure reliable comparison of results generated over a long period of time or independent experiments. The recommendations for an improved model presented here will prove to be helpful for reproducible, independent comparison of the anti-inflammatory potential of wild-type or recombinant candidate probiotic strains, whether administered as pure cultures or as blends.

Improved antimicrobial therapy with cationic tetra- and octa-substituted phthalocyanines

NASA Astrophysics Data System (ADS)

Angelov, I.; Mantareva, V.; Kussovski, V.; Woehrle, D.; Borisova, E.; Avramov, L.

2008-12-01

Photodynamic therapy (PDT) today is an innovative and not yet widespread light-drug initiated treatment that is based on the photoactive compound irradiated with proper light to produce oxygen species that are toxic to the pathogenic biological objects- bacteria, viruses, tumor cells. The obstacles that limited the efficacy of PDT concern to the selectivity and multi-drug resistance prolong time for cellular release and side effects of skin photosensitivity for commercial porphyrin originated photosensitizers (PS). Now there are very intensive investigations for introducing in practice a new, with a least side effects PSs for PDT. The usefulness of the more extended macromolecules structured with proper substituents refers not only to the improved optical properties like far-red and with intensive absorption and emission capacity, but mainly to the ability for selective delivery and adhesion to the target cells, such as bacteria or other pathogens. The present study focuses on the charge effect of photodynamic agent on the uptake capacity toward gram-negative bacteria cells and their further photoinactivation. The multi-drug resistant microorganism Aeromanas hydrophilla, which is causing diseases to fishes and humans, is treated. The new octa-cationic phthalocyanines are designed to compare PDT efficacy to the efficacy of tetra-substituted derivatives with the same functional peripheral substituents. The higher cellular accumulation to the bacteria cells as a result of the high number of positive charges of photosensitizer, leading to the better adhesion to the cellular membranes and improved photoinactivation of bacteria causing superficial and intraorgan infections. These results set a base of a rationale design of covalently octa-substituted phthalocyanines with positive charge for a successful treatment of microorganisms.

Airborne bacteria in the atmosphere: Presence, purpose, and potential

NASA Astrophysics Data System (ADS)

Smets, Wenke; Moretti, Serena; Denys, Siegfried; Lebeer, Sarah

2016-08-01

Numerous recent studies have highlighted that the types of bacteria present in the atmosphere often show predictable patterns across space and time. These patterns can be driven by differences in bacterial sources of the atmosphere and a wide range of environmental factors, including UV intensity, precipitation events, and humidity. The abundance of certain bacterial taxa is of interest, not only for their ability to mediate a range of chemical and physical processes in the atmosphere, such as cloud formation and ice nucleation, but also for their implications -both beneficial and detrimental-for human health. Consequently, the widespread importance of airborne bacteria has stimulated the search for their applicability. Improving air quality, modelling the dispersal of airborne bacteria (e.g. pathogens) and biotechnological purposes are already being explored. Nevertheless, many technological challenges still need to be overcome to fully understand the roles of airborne bacteria in our health and global ecosystems.

Improved antimicrobial activity of Pediococcus acidilactici against Salmonella Gallinarum by UV mutagenesis and genome shuffling.

PubMed

Han, Geon Goo; Song, Ahn Ah; Kim, Eun Bae; Yoon, Seong-Hyun; Bok, Jin-Duck; Cho, Chong-Su; Kil, Dong Yong; Kang, Sang-Kee; Choi, Yun-Jaie

2017-07-01

Pediococcus acidilactici is a widely used probiotic, and Salmonella enterica serovar Gallinarum (SG) is a significant pathogen in the poultry industry. In this study, we improved the antimicrobial activity of P. acidilactici against SG using UV mutation and genome shuffling (GS). To improve antimicrobial activity against SG, UV mutagenesis was performed against wild-type P. acidilactici (WT), and five mutants showed improved antimicrobial activity. To further improve antimicrobial activity, GS was performed on five UV mutants. Following GS, four mutants showed improved antimicrobial activity compared with the UV mutants and WT. The antimicrobial activity of GS1 was highest among the mutants; however, the activity was reduced when the culture supernatant was treated with proteinase K, suggesting that the improved antimicrobial activity is due to a proteinous substance such as bacteriocin. To validate the activity of GS1 in vivo, we designed multi-species probiotics and performed broiler feeding experiments. Groups consisted of no treatment (NC), avilamycin-treated (PC), probiotic group 1 containing WT (T1), and probiotic group 2 containing GS1 (T2). In broiler feeding experiments, coliform bacteria were significantly reduced in T2 compared with NC, PC, and T1. The cecal microbiota was modulated and pathogenic bacteria were reduced by GS1 oral administration. In this study, GS1 showed improved antimicrobial activity against SG in vitro and reduced pathogenic bacteria in a broiler feeding experiment. These results suggest that GS1 can serve as an efficient probiotic, as an alternative to antibiotics in the poultry industry.

[Bio-ecological control of chronic liver disease and encephalopathy].

PubMed

Bengmark, S; Di Cocco, P; Clemente, K; Corona, L; Angelico, R; Manzia, T; Famulari, A; Pisani, F; Orlando, G

2011-08-01

Minimal encephalopathy was originally associated with chronic liver disease but is increasingly associated with most other chronic diseases and particularly with diabetes and also chronic disorders in other organs: kidneys, lungs, thyroid and with obesity. It is increasingly with dramatically increased and more or less permanent increase in systemic inflammation, most likely a result of Western lifestyle. Frequent physical exercise and intake of foods rich in vitamins, antioxidants, fibres, lactic acid bacteria etc in combination with reduction in intake of refined and processed foods is known to reduce systemic inflammation and prevent chronic diseases. Some lactic acid bacteria, especially Lb paracasei, lb plantarum and pediococcus pentosaceus have proven effective to reduce inflammation and eliminate encephalopathy. Significant reduction in blood ammonia levels and endotoxin levels were reported in parallel to improvement of liver disease. Subsequent studies with other lactic acid bacteria seem to demonstrate suppression of inflammation and one study also provides evidence of clinical improvement.

Phytoremediation of Polychlorinated Biphenyls: New Trends and Promises

PubMed Central

Van Aken, Benoit; Correa, Paola A.; Schnoor, Jerald L.

2011-01-01

Transgenic plants and associated bacteria constitute a new generation of genetically modified organisms for efficient and environmental-friendly treatment of soil and water contaminated with polychlorinated biphenyls (PCBs). This review focuses on recent advances in phytoremediation for the treatment of PCBs, including the development of transgenic plants and associated bacteria. Phytoremediation, or the use of higher plants for rehabilitation of soil and groundwater, is a promising strategy for cost-effective treatment of sites contaminated by toxic compounds, including toxic PCBs. Plants can help mitigate environmental pollution by PCBs through a range of mechanisms: besides uptake from soil (phytoextraction), plants are capable of enzymatic transformation of PCBs (phytotransformation); by releasing a variety of secondary metabolites, plants also enhance the microbial activity in the root zone, improving biodegradation of PCBs (rhizoremediation). However, because of their hydrophobicity and chemical stability, PCBs are only slowly taken up and degraded by plants and associated bacteria, resulting in incomplete treatment and potential release of toxic metabolites into the environment. Moreover, naturally occurring plant-associated bacteria may not possess the enzymatic machinery necessary for PCB degradation. In order to overcome these limitations, bacterial genes involved in the metabolism of PCBs, such as biphenyl dioxygenases, have been introduced into higher plants, following a strategy similar to the development of transgenic crops. Similarly, bacteria have then been genetically modified that exhibit improved biodegradation capabilities and are able to maintain stable relationships with plants. Transgenic plants and associated bacteria bring hope for a broader and more efficient application of phytoremediation for the treatment of PCBs. PMID:20384372

Isolation and identification of bacteria to improve the strength of concrete.

PubMed

Krishnapriya, S; Venkatesh Babu, D L; G, Prince Arulraj

2015-05-01

The objective of this research work is to isolate and identify calcite precipitating bacteria and to check the suitability of these bacteria for use in concrete to improve its strength. Bacteria to be incorporated in concrete should be alkali resistant to endure the high pH of concrete and endospore forming to withstand the mechanical stresses induced in concrete during mixing. They must exhibit high urease activity to precipitate calcium carbonate in the form of calcite. Bacterial strains were isolated from alkaline soil samples of a cement factory and were tested for urease activity, potential to form endospores and precipitation of calcium carbonate. Based on these results, three isolates were selected and identified by 16S rRNA gene sequencing. They were identified as Bacillus megaterium BSKAU, Bacillus licheniformis BSKNAU and Bacillus flexus BSKNAU. The results were compared with B. megaterium MTCC 1684 obtained from Microbial Type Culture Collection and Gene Bank, Chandigarh, India. Experimental work was carried out to assess the influence of bacteria on the compressive strength and tests revealed that bacterial concrete specimens showed enhancement in compressive strength. The efficiency of bacteria toward crack healing was also tested. Substantial increase in strength and complete healing of cracks was observed in concrete specimens cast with B. megaterium BSKAU, B. licheniformis BSKNAU and B. megaterium MTCC 1684. This indicates the suitability of these bacterial strains for use in concrete. The enhancement of strength and healing of cracks can be attributed to the filling of cracks in concrete by calcite which was visualized by scanning electron microscope. Copyright © 2015 Elsevier GmbH. All rights reserved.

Diagnostic Value of PCR Analysis of Bacteria and Fungi from Blood in Empiric-Therapy-Resistant Febrile Neutropenia ▿

PubMed Central

Nakamura, Akiko; Sugimoto, Yuka; Ohishi, Kohshi; Sugawara, Yumiko; Fujieda, Atsushi; Monma, Fumihiko; Suzuki, Kei; Masuya, Masahiro; Nakase, Kazunori; Matsushima, Yoshiko; Wada, Hideo; Katayama, Naoyuki; Nobori, Tsutomu

2010-01-01

This study aimed to assess the clinical utility of PCR for the analysis of bacteria and fungi from blood for the management of febrile neutropenic patients with hematologic malignancies. Using a PCR system able to detect a broad range of bacteria and fungi, we conducted a prospective pilot study of periodic analyses of blood from patients following intensive chemotherapy. When fever occurred, it was treated with empirical antibiotic therapy, basically without knowledge of the PCR results. In 23 febrile episodes during the neutropenic period, bacteria were detected by PCR in 11 cases, while the same species were identified by blood culture in 3 cases. In 10 out of 11 PCR-positive cases, fever could be managed by empirical therapy. In the empirical-therapy-resistant case, the identification of Stenotrophomonas maltophilia by PCR led to improvement of fever. No fungi were detected by PCR in febrile cases, while Aspergillus fumigatus was detected in one afebrile patient, several days before a clinical diagnosis was made. In subsequent sporadic PCR analyses in 15 cases of febrile neutropenia, bacteria were detected by both PCR and blood culture in 7 cases and by PCR alone in 6. Fungi were not detected. While fever was improved by empirical therapy in 12 out of the 13 PCR-positive cases, the identification of Pseudomonas aeruginosa by PCR in one therapy-resistant case contributed to the successful treatment of persistent fever. Our results indicate that PCR analysis of bacteria from blood provides essential information for managing empirical-therapy-resistant febrile neutropenia. PMID:20392911

The effect of two different interval-training programmes on physiological and performance indices.

PubMed

Sindiani, Mahmood; Eliakim, Alon; Segev, Daria; Meckel, Yoav

2017-08-01

The aim of the present study was to compare the effect of an increasing-distance, interval-training programme and a decreasing-distance, interval-training programme, matched for total distance, on aerobic and anaerobic physiological indices. Forty physical education students were randomly assigned to either the increasing- or decreasing-distance, interval-training group (ITG and DTG), and completed two similar relevant sets of tests before and after six weeks of training. One training programme consisted of increasing-distance interval-training (100-200-300-400-500 m) and the other decreasing-distance interval training (500-400-300-200-100 m). While both training programmes led to a significant improvement in VO 2 max (ES = 0.83-1.25), the improvement in the DTG was significantly greater than in the ITG (14.5 ± 3.6 vs. 7.8 ± 3.2%, p < .05). In addition, while both training programmes led to a significant improvement in all anaerobic indices (ES = 0.83-1.63), the improvements in peak power (15.7 ± 7.8 vs. 8.9 ± 4.7), mean power (10.6 ± 5.4 vs. 6.8 ± 4.4), and fatigue index (18.2 ± 10.9 vs. 7.0 ± 14.2) were significantly greater in the DTG compared to the ITG (p < .05). The main finding of the present study was that beyond the significant positive effects of both training programmes on aerobic and anaerobic fitness, the DTG showed significant superiority over the ITG in improving aerobic and anaerobic performance capabilities. Coaches and athletes should therefore be aware that, in spite of identical total work, an interval-training programme might induce different physiological impacts if the order of intervals is not identical.

Diagnosis of bacterial ventilator-associated pneumonia in children: reproducibility of blind bronchial sampling.

PubMed

Sachdev, Anil; Chugh, Krishan; Raghunathan, Veena; Gupta, Dhiren; Wattal, Chand; Menon, Geetha R

2013-01-01

To evaluate the reproducibility of blind bronchial sampling in patients with suspected diagnosis of bacterial ventilator-associated pneumonia. Prospective study. Pediatric intensive care unit of a tertiary care, multidisciplinary, teaching hospital in Northern India. All consecutive patients on mechanical ventilation for >48 hrs were evaluated clinically for ventilator-associated pneumonia. Children with clinical ventilator-associated pneumonia were subjected to blind bronchial sampling twice. Sixty-eight blind bronchial sampling samples from 34 patients were analyzed for polymorphonuclear cells, the presence, type, and number of bacteria. Acinetobacter baumannii was the most common organism grown from distal respiratory secretions. For polymorphonuclear cells, the concordance between two blind bronchial samples was 85.3% and kappa coefficient was 0.65. The concordance for the presence and type of bacteria in Gram staining in two samples was 85.3% and kappa coefficient was 0.68. The intraclass coefficients for bacterial index and predominant species index were 0.82 (95% confidence interval 0.65-0.91) and 0.89 (95% confidence interval 0.78-0.94), respectively. The use of prior antibiotics did not adversely affect the reproducibility of blind bronchial sampling. No major complications were recorded during the procedure. Blind bronchial sampling of lower respiratory tract secretions in mechanically ventilated patients generates reproducible results of quantitative and qualitative cultures. We suggest that blind bronchial sampling may provide valuable clue to the bacterial etiology in ventilated child with suspected clinical ventilator-associated pneumonia.

Antibiotic-resistant Gram-negative bacteremia in pediatric oncology patients--risk factors and outcomes.

PubMed

Haeusler, Gabrielle M; Mechinaud, Francoise; Daley, Andrew J; Starr, Mike; Shann, Frank; Connell, Thomas G; Bryant, Penelope A; Donath, Susan; Curtis, Nigel

2013-07-01

Infection with antibiotic-resistant (AR) Gram-negative (GN) bacteria is associated with increased morbidity and mortality. The aim of this study was to determine risk factors and outcomes associated with GN bacteremia with acquired resistance to antibiotics used in the empiric treatment of febrile neutropenia in pediatric oncology patients at our institution. All episodes of GN bacteremia in oncology patients at the Royal Children's Hospital Melbourne, from 2003 to 2010 were retrospectively reviewed. Information regarding age, diagnosis, phase of treatment, inpatient status, previous AR GN infection, treatment with inotropes or ventilatory support, admission to intensive care unit, and hospital and intensive care unit length of stay were obtained from electronic records. A total of 280 episodes of GN bacteremia in 210 patients were identified. Of these, 42 episodes in 35 patients were caused by an AR GN organism. Factors independently associated with AR GN bacteremia were high-intensity chemotherapy (odds ratio 3.7, 95% confidence interval: 1.2-11.4), hospital-acquired bacteremia (odds ratio 4.3, 95% confidence interval: 2.0-9.6) and isolation of AR GN bacteria from any site within the preceding 12 months (odds ratio 9.9, 95% confidence interval: 3.8-25.5). Episodes of AR GN bacteremia were associated with longer median hospital length of stay (23.5 days versus 14.0 days; P = 0.0007), longer median intensive care unit length of stay (3.8 days versus 1.6 days; P = 0.02) and a higher rate of invasive ventilation (15% versus 5.2%; P = 0.03). No significant difference in infection-related or all-cause mortality between the 2 groups was identified. In pediatric oncology patients, AR GN bacteremia is associated with an increased rate of adverse outcomes and is more likely in patients who have received high-intensity chemotherapy, have been in hospital beyond 48 hours and who have had previous AR GN infection or colonization.

Antimicrobial effects of a new therapeutic liquid dentifrice formulation on oral bacteria including odorigenic species.

PubMed

Sreenivasan, P K; Furgang, D; Zhang, Y; DeVizio, W; Fine, D H

2005-03-01

The control of oral malodor is well-recognized in efforts to improve oral health. Antimicrobial formulations can mitigate oral malodor, however, procedures to assess effects on oral bacteria including those implicated in halitosis are unavailable. This investigation examined the antimicrobial effects of a new liquid triclosan/copolymer dentifrice (test) formulation that demonstrated significant inhibition of oral malodor in previous organoleptic clinical studies. Procedures compared antimicrobial effects of the test and control formulations on a range of oral micro-organisms including members implicated in halitosis, substantive antimicrobial effects of formulations with hydroxyapatite as a surrogate for human teeth and ex vivo effects on oral bacteria from human volunteers. With Actinomyces viscosus, as a model system, the test formulation demonstrated a dose-dependent effect. At these concentrations the test formulation provided significant antimicrobial effects on 13 strains of oral bacteria including those implicated in bad breath at selected posttreatment time points. Treatment of hydroxyapatite by the test dentifrice resulted in a significant and substantive antimicrobial effect vs. controls. Oral bacteria from subjects treated ex vivo with the test dentifrice resulted in significant reductions in cultivable oral bacteria and odorigenic bacteria producing hydrogen sulfide. In summary, microbiological methods adapted to study odorigenic bacteria demonstrate the significant antimicrobial effects of the test (triclosan/copolymer) dentifrice with laboratory and clinical strains of oral bacteria implicated in bad breath.

Relative safety of pooled whole blood-derived versus single-donor (apheresis) platelets in the United States: a systematic review of disparate risks.

PubMed

Vamvakas, Eleftherios C

2009-12-01

Risks of transfusion-transmitted infections (TTIs), transfusion-associated sepsis (TAS), and transfusion-related acute lung injury (TRALI) were compared between pooled whole blood-derived (PWBD) and single-donor platelets (PLTs) transfused in the United States. The literature was searched for estimates of the risk of TTIs and TAS and of the effect on bacterial contamination of PLTs of process improvements, bacterial culture, and surrogate methods to detect bacteria. Seven studies published between January 2005 and December 2008 and comparing bacterial contamination frequency between PWBD and single-donor PLTs after implementing bacterial culture testing of both components were subjected to meta-analysis. The three retrieved studies diagnosing TRALI based on the 2004 consensus definition in settings transfusing both PWBD and single-donor PLTs were not amenable to meta-analysis and were assessed qualitatively. Under a best-case scenario, if 100% (from the current 12.5%) of PLT doses were provided as PWBD PLTs, the number of additional transmissions of human immunodeficiency virus, hepatitis C virus, hepatitis B virus, bacteria, or a novel pathogen annually could be 1.2, 1.3, 9.0, 105.3, or 69.2 to 252.6, respectively. Compared with single-donor PLTs, US PLT pools of five concentrates have a 5.6-fold higher risk of bacterial contamination (summary odds ratio, 5.58; 95% confidence interval, 2.60-11.98; p < 0.05). The three studies that diagnosed TRALI based on the consensus definition did not demonstrate a difference in risk between PWBD and single-donor PLTs. TTIs and TAS determine the relative safety of PWBD versus single-donor PLTs. The available limited data do not support a higher risk of TRALI from single-donor (compared with PWBD) PLTs.

Poor health knowledge and behaviour is a risk for the spread of antibiotic resistance: survey of higher secondary school students in Goa, India.

PubMed

Almeida Santimano, Nerissa Ml; Foxcroft, David R

2017-03-01

We assessed antibiotic knowledge and practice among youth in India, where antibiotics are widely available without prescription. Randomly selected school questionnaire survey representing four regions in Goa, India, with students ( n = 773) aged 16-17. Most students (67%) were unaware of the problem of antibiotic resistance, with around half (49%) mistakenly thinking that bacteria cause cold or flu. Around one-fifth (19%) said they frequently self-medicate with antibiotics, 57% would discontinue antibiotics when symptoms alleviated and 24% stored unused antibiotics at home. Generalised linear mixed models (GLMM) showed that females consistently had poorer antibiotic knowledge than males. Especially notable were the higher odds in females for reporting incorrectly that antibiotics kill harmful viruses (odds ratio (OR) = 1.93; 99.5% confidence interval (CI) = 1.09-3.41) and for reporting incorrectly that antibiotics do not kill harmless bacteria (OR = 2.02; 99.5% CI = 1.16-3.51). Poor antibiotic practice was not clearly differentiated between males and females. In terms of poor antibiotic practice, one model showed notable results for educational stream: both arts and commerce students were more likely than science students to say they would discontinue antibiotics when symptoms alleviated and before the antibiotic course of treatment was finished (arts: OR = 2.76; 99.5% CI = 1.58-4.82 and commerce: OR = 1.79; 99.5% CI = 1.06-3.04). Young adults in India had poor antibiotic knowledge and practice. Efforts to improve antibiotic health knowledge and safe practice are required to help prevent the spread of antibiotic resistance.

An in vitro study of the anti-microbial efficacy of a 1% silver sulphadiazine and 0.2% chlorhexidine digluconate cream, 1% silver sulphadiazine cream and a silver coated dressing.

PubMed

Fraser, John F; Bodman, Jan; Sturgess, Ruth; Faoagali, Joan; Kimble, Roy M

2004-02-01

Burn sepsis is a leading cause of mortality and morbidity in patients with major burns. The use of topical anti-microbial agents has helped improve the survival in these patients. There are a number of anti-microbials available, one of which, Silvazine (1% silver sulphadiazine (SSD) and 0.2% chlorhexidine digluconate), is used only in Australasia. No study, in vitro or clinical, had compared Silvazine with the new dressing Acticoat. This study compared the anti-microbial activity of Silvazine, Acticoat and 1% silver sulphadiazine (Flamazine) against eight common burn wound pathogens. Each organism was prepared as a suspension. A 10 microl inoculum of the chosen bacterial isolate (representing approximately between 10(4) and 10(5) total bacteria) was added to each of four vials, followed by samples of each dressing and a control. The broths were then incubated and 10 microl loops removed at specified intervals and transferred onto Horse Blood Agar. These plates were then incubated for 18 hours and a colony count was performed. The data demonstrates that the combination of 1% SSD and 0.2% chlorhexidine digluconate (Silvazine) results in the most effective killing of all bacteria. SSD and Acticoat had similar efficacies against a number of isolates, but Acticoat seemed only bacteriostatic against E. faecalis and methicillin-resistant Staphylococcus aureus. Viable quantities of Enterobacter cloacae and Proteus mirabilis remained at 24h. The combination of 1% SSD and 0.2% chlorhexidine digluconate (Silvazine) is a more effective anti-microbial against a number of burn wound pathogens in this in vitro study. A clinical study of its in vivo anti-microbial efficacy is required.

Bacteria, biofilm and honey: a study of the effects of honey on 'planktonic' and biofilm-embedded chronic wound bacteria.

PubMed

Merckoll, Patricia; Jonassen, Tom Øystein; Vad, Marie Elisabeth; Jeansson, Stig L; Melby, Kjetil K

2009-01-01

Chronically infected wounds are a costly source of suffering. An important factor in the failure of a sore to heal is the presence of multiple species of bacteria, living cooperatively in highly organized biofilms. The biofilm protects the bacteria from antibiotic therapy and the patient's immune response. Honey has been used as a wound treatment for millennia. The components responsible for its antibacterial properties are now being elucidated. The study aimed to determine the effects of different concentrations of 'Medihoney' therapeutic honey and Norwegian Forest Honey 1) on the real-time growth of typical chronic wound bacteria; 2) on biofilm formation; and 3) on the same bacteria already embedded in biofilm. Reference strains of MRSE, MRSA, ESBL Klebsiella pneumoniae and Pseudomonas aeruginosa were incubated with dilution series of the honeys in microtitre plates for 20 h. Growth of the bacteria was assessed by measuring optical density every 10 min. Growth curves, biofilm formation and minimum bactericidal concentrations are presented. Both honeys were bactericidal against all the strains of bacteria. Biofilm was penetrated by biocidal substances in honey. Reintroduction of honey as a conventional wound treatment may help improve individual wound care, prevent invasive infections, eliminate colonization, interrupt outbreaks and thereby preserve current antibiotic stocks.

Effect of interval training on cognitive functioning and cerebral oxygenation in obese patients: a pilot study.

PubMed

Drigny, Joffrey; Gremeaux, Vincent; Dupuy, Olivier; Gayda, Mathieu; Bherer, Louis; Juneau, Martin; Nigam, Anil

2014-11-01

To assess the effect of a 4-month high-intensity interval training programme on cognitive functioning, cerebral oxygenation, central haemodynamic and cardiometabolic parameters and aerobic capacity in obese patients. Cognitive functioning, cerebral oxygenation, central haemodynamic, cardiometabolic and exercise para-meters were measured before and after a 4-month high-intensity interval training programme in 6 obese patients (mean age 49 years (standard deviation 8), fat mass percentage 31 ± 7%). Body composition (body mass, total and trunk fat mass, waist circumference) and fasting insulin were improved after the programme (p < 0.05). V. O2 and power output at ventilatory threshold and peak power output were improved after the programme (p < 0.05). Cognitive functioning, including short-term and verbal memory, attention and processing speed, was significantly improved after training (p < 0.05). Cerebral oxygen extraction was also improved after training (p < 0.05). These preliminary results indicate that a 4-month high-intensity interval training programme in obese patients improved both cognitive functioning and cere-bral oxygen extraction, in association with improved exercise capacity and body composition.

Recombinant human deoxyribonuclease improves atelectasis in mechanically ventilated children with cardiac disease.

PubMed

Prodhan, Parthak; Greenberg, B; Bhutta, Adnan T; Hyde, Carrie; Vankatesan, Ajay; Imamura, Michiaki; Jaquiss, Robert Db; Dyamenahalli, Umesh

2009-01-01

To investigate whether a mucolytic agent, recombinant human deoxyribonuclease (rhDNase), improves atelectasis in children with cardiac illness requiring mechanical ventilation. A retrospective cohort study on consecutive patients receiving short-term (< or =14 days) rhDNase therapy for atelectasis in the cardiac intensive care unit from January 2005 through February 2007 was carried out. Data relating to patient characteristics, gas exchange, ventilatory parameters, and chest radiographs were collected and analyzed. The effectiveness of rhDNase therapy in the presence of neutrophils and/or bacteria in the pre-rhDNase therapy tracheal aspirates was also investigated. rhDNase was effective in significantly improving established atelectasis without any major changes in gas exchange and ventilatory parameters. Therapeutic effect of rhDNase is most effective in ameliorating atelectasis in the lungs within 10 doses. rhDNase was more effective in improving chest radiographic atelectasis score in patients who had > moderate amounts of polymophonuclear neutrophils (P value = 0.0008), or bacteria (P value = 0.007) or both (P value = 0.004) present in their pre-rhDNase therapy trachea aspirate. No adverse effects were seen with rhDNase administration in the study cohort. rhDNase can be safely and effectively used to improve atelectasis in mechanically ventilated children with cardiac disease especially in the presence of bacteria and/or moderate amounts of polymophonuclear neutrophils in the pre-rhDNase therapy tracheal aspirate.

Recombinant Human Deoxyribonuclease Improves Atelectasis in Mechanically Ventilated Children with Cardiac Disease

PubMed Central

Prodhan, P; Greenberg, B; Bhutta, AT; Hyde, C; Vankatesan, A; Imamura, M; Jaquiss, RDB; Dyamenahalli, U

2010-01-01

Objective To investigate if a mucolytic agent, recombinant human deoxyribonuclease (rhDNase), improves atelectasis in children with cardiac illness requiring mechanical ventilation. Design A retrospective cohort study on consecutive patients receiving short-term (≤ 14 days) rhDNase therapy for atelectasis in the cardiac intensive care unit from January 2005 through February 2007 was carried out. Data relating to patient characteristics, gas exchange, ventilatory parameters and chest radiographs was collected and analyzed. The effectiveness of rhDNase therapy in the presence of neutrophils and/ or bacteria in the pre-rhDNase therapy tracheal aspirates was also investigated. Results rhDNase was effective in significantly improving established atelectasis without any major changes in gas exchange and ventilatory parameters. Therapeutic effect of rhDNase is most effective in ameliorating atelectasis in the lungs within 10 doses. rhDNase was more effective in improving chest radiographic atelectasis score in patients who had > moderate amounts PMN (p value= 0.0008), or bacteria (p value=0.007) or both (p value =0.004) present in their pre-rhDNase therapy trachea aspirate. No adverse effects were seen with rhDNase administration in the study cohort. Conclusions rhDNase can be safely and effectively used to improve atelectasis in mechanically ventilated children with cardiac disease especially in the presence of bacteria and/ or moderate amounts of PMN in the pre-rhDNase therapy tracheal aspirate. PMID:19489944

New Techniques for the Generation and Analysis of Tailored Microbial Systems on Surfaces.

PubMed

Furst, Ariel L; Smith, Matthew J; Francis, Matthew B

2018-05-17

The interactions between microbes and surfaces provide critically important cues that control the behavior and growth of the cells. As our understanding of complex microbial communities improves, there is a growing need for experimental tools that can establish and control the spatial arrangements of these cells in a range of contexts. Recent improvements in methods to attach bacteria and yeast to nonbiological substrates, combined with an expanding set of techniques available to study these cells, position this field for many new discoveries. Improving methods for controlling the immobilization of bacteria provides powerful experimental tools for testing hypotheses regarding microbiome interactions, studying the transfer of nutrients between bacterial species, and developing microbial communities for green energy production and pollution remediation.

Development of an improved rapid BACpro® protocol and a method for direct identification from blood-culture-positive bottles using matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

PubMed

Yonezawa, Takatoshi; Watari, Tomohisa; Ashizawa, Kazuho; Hanada, Daisuke; Yanagiya, Takako; Watanabe, Naoki; Terada, Takashi; Tomoda, Yutaka; Fujii, Satoshi

2018-05-01

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been incorporated into pathogenic bacterial identification methods and has improved their rapidity. Various methods have been reported to directly identify bacteria with MALDI-TOF MS by pretreating culture medium in blood culture bottles. Rapid BACpro® (Nittobo Medical Co., Ltd.) is a pretreatment kit for effective collection of bacteria with cationic copolymers. However, the Rapid BACpro® pretreatment kit is adapted only for MALDI Biotyper (Bruker Daltonics K.K.), and there has been a desire to expand its use to VITEK MS (VMS; bioMerieux SA). We improved the protocol and made it possible to analyze with VMS. The culture medium bacteria collection method was changed to a method with centrifugation after hemolysis using saponin; the cationic copolymer concentration was changed to 30% of the original concentration; the sequence with which reagents were added was changed; and a change was made to an ethanol/formic acid extraction method. The improved protocol enhanced the identification performance. When VMS was used, the identification rate was 100% with control samples. With clinical samples, the identification agreement rate with the cell smear method was 96.3%. The improved protocol is effective in blood culture rapid identification, being both simpler and having an improved identification performance compared with the original. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of high pressure treatment on microbiological quality of Indian white prawn (Fenneropenaeus indicus) during chilled storage.

PubMed

Ginson, J; Panda, Satyen Kumar; Bindu, J; Kamalakanth, C K; Srinivasa Gopal, T K

2015-04-01

High pressure treatment of 250 MPa for 6 min at 25 °C was applied to headless Indian white prawn (Fenneropenaeus indicus) to evaluate changes in microbiological characteristics of the species during chilled storage. Changes in load of mesophilic bacteria, psychrotrophic bacteria, proteolytic bacteria, Enterobacteriaceae, Pseudomonas spp., H2S producing bacteria, lactic acid bacteria, Brochothrix thermosphacta and yeast & mold were estimated in pressurized and un-pressurized samples during chilled storage. All microbes were reduced significantly after high pressure treatment and there was significant difference in microbial quality of control and high pressure treated samples in the entire duration of chilled storage (p < 0.05). There was delay in the growth of Enterobacteriaceae and H2S producing bacteria up to 6th and 9th day of storage, respectively in high pressure treated samples. In high pressure treated sample, no lag phase (λ) was observed for psychrotrophic bacteria, H2S producing bacteria, B. thermosphacta, Pseudomonas spp. and lactic acid bacteria; however, other bacteria showed a reduced lag phase during chilled storage. Kinetic parameter such as specific growth rate (μmax) in high pressure treated samples was significantly reduced in most of the bacterial groups except for psychrotrophic bacteria, Enterobacteriaceae and lactic acid bacteria. Mesophilic bacterial count of control samples crossed the marginal limit of acceptability on 12th day and unacceptable limit on 18th day of storage, whereas high pressure treated samples never breached the acceptability limit during entire duration of chilled storage. The present study indicated that application of high pressure processing can be used to improve microbial quality of Indian white prawn and extend the chilled storage life. Copyright © 2014 Elsevier Ltd. All rights reserved.

Separation of Bacteria, Protozoa and Carbon Nanotubes by Density Gradient Centrifugation

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

Mortimer, Monika; Petersen, Elijah; Buchholz, Bruce

Sustainable production and use of carbon nanotube (CNT)-enabled materials require efficient assessment of CNT environmental hazards, including the potential for CNT bioaccumulation and biomagnification in environmental receptors. Microbes, as abundant organisms responsible for nutrient cycling in soil and water, are important ecological receptors for studying the effects of CNTs. Quantification of CNT association with microbial cells requires efficient separation of CNT-associated cells from individually dispersed CNTs and CNT agglomerates. Here in this paper, we designed, optimized, and demonstrated procedures for separating bacteria (Pseudomonas aeruginosa) from unbound multiwall carbon nanotubes (MWCNTs) and MWCNT agglomerates using sucrose density gradient centrifugation. We demonstratemore » separation of protozoa (Tetrahymena thermophila) from MWCNTs, bacterial agglomerates, and protozoan fecal pellets by centrifugation in an iodixanol solution. The presence of MWCNTs in the density gradients after centrifugation was determined by quantification of 14C-labeled MWCNTs; the recovery of microbes from the density gradient media was confirmed by optical microscopy. Protozoan intracellular contents of MWCNTs and of bacteria were also unaffected by the designed separation process. Lastly, the optimized methods contribute to improved efficiency and accuracy in quantifying MWCNT association with bacteria and MWCNT accumulation in protozoan cells, thus supporting improved assessment of CNT bioaccumulation.« less

Separation of Bacteria, Protozoa and Carbon Nanotubes by Density Gradient Centrifugation

DOE PAGES

Mortimer, Monika; Petersen, Elijah; Buchholz, Bruce; ...

2016-10-12

Sustainable production and use of carbon nanotube (CNT)-enabled materials require efficient assessment of CNT environmental hazards, including the potential for CNT bioaccumulation and biomagnification in environmental receptors. Microbes, as abundant organisms responsible for nutrient cycling in soil and water, are important ecological receptors for studying the effects of CNTs. Quantification of CNT association with microbial cells requires efficient separation of CNT-associated cells from individually dispersed CNTs and CNT agglomerates. Here in this paper, we designed, optimized, and demonstrated procedures for separating bacteria (Pseudomonas aeruginosa) from unbound multiwall carbon nanotubes (MWCNTs) and MWCNT agglomerates using sucrose density gradient centrifugation. We demonstratemore » separation of protozoa (Tetrahymena thermophila) from MWCNTs, bacterial agglomerates, and protozoan fecal pellets by centrifugation in an iodixanol solution. The presence of MWCNTs in the density gradients after centrifugation was determined by quantification of 14C-labeled MWCNTs; the recovery of microbes from the density gradient media was confirmed by optical microscopy. Protozoan intracellular contents of MWCNTs and of bacteria were also unaffected by the designed separation process. Lastly, the optimized methods contribute to improved efficiency and accuracy in quantifying MWCNT association with bacteria and MWCNT accumulation in protozoan cells, thus supporting improved assessment of CNT bioaccumulation.« less

Comparing Two Antibacterial Treatments for Bioceramic Coatings at Short Culture Times

NASA Astrophysics Data System (ADS)

Melero, H.; Madrid, C.; Fernández, J.; Guilemany, J. M.

2014-04-01

Plasma-sprayed hydroxyapatite coatings were employed industrially for decades to improve osteointegration of articular implants, but many studies have warned about the problems inherent to this procedure (mechanical properties, harmful phases). Consequently, a combination of hydroxyapatite with TiO2 sprayed by high velocity oxy-fuel spray was considered in this study. As infection after joint replacement surgery is one of the most critical concerns when considering implant performance, it is necessary to study possible ways to reduce or eliminate it. Two coating treatments were chosen for this study: addition of a percentage of ZnO and immersion in gentamicin for 24 h. Furthermore, three bacteria were considered: Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The evolution of bacteria viability in solution was measured at 0, 2, and 4 h; and plate assays were performed to study antibacterial effects by diffusion. The results show an important antibacterial effect of the as-sprayed coating, attributed to the presence of -OH radicals on the surface. The presence of ZnO did not have any additional influence on bacteria viability, but gentamicin-treated samples showed an improvement in antibacterial behavior for Gram-negative bacteria in solution, as well as a bactericidal effect in diffusion conditions.

Separation of Bacteria, Protozoa and Carbon Nanotubes by Density Gradient Centrifugation

PubMed Central

Mortimer, Monika; Petersen, Elijah J.; Buchholz, Bruce A.; Holden, Patricia A.

2016-01-01

Sustainable production and use of carbon nanotube (CNT)-enabled materials require efficient assessment of CNT environmental hazards, including the potential for CNT bioaccumulation and biomagnification in environmental receptors. Microbes, as abundant organisms responsible for nutrient cycling in soil and water, are important ecological receptors for studying the effects of CNTs. Quantification of CNT association with microbial cells requires efficient separation of CNT-associated cells from individually dispersed CNTs and CNT agglomerates. Here, we designed, optimized, and demonstrated procedures for separating bacteria (Pseudomonas aeruginosa) from unbound multiwall carbon nanotubes (MWCNTs) and MWCNT agglomerates using sucrose density gradient centrifugation. We demonstrate separation of protozoa (Tetrahymena thermophila) from MWCNTs, bacterial agglomerates, and protozoan fecal pellets by centrifugation in an iodixanol solution. The presence of MWCNTs in the density gradients after centrifugation was determined by quantification of 14C-labeled MWCNTs; the recovery of microbes from the density gradient media was confirmed by optical microscopy. Protozoan intracellular contents of MWCNTs and of bacteria were also unaffected by the designed separation process. The optimized methods contribute to improved efficiency and accuracy in quantifying MWCNT association with bacteria and MWCNT accumulation in protozoan cells, thus supporting improved assessment of CNT bioaccumulation. PMID:27917301

Cold Stress Tolerance in Psychrotolerant Soil Bacteria and Their Conferred Chilling Resistance in Tomato (Solanum lycopersicum Mill.) under Low Temperatures

PubMed Central

Subramanian, Parthiban; Kim, Kiyoon; Krishnamoorthy, Ramasamy; Mageswari, Anbazhagan; Selvakumar, Gopal; Sa, Tongmin

2016-01-01

The present work aimed to study the culturable diversity of psychrotolerant bacteria persistent in soil under overwintering conditions, evaluate their ability to sustain plant growth and alleviate chilling stress in tomato. Psychrotolerant bacteria were isolated from agricultural field soil samples colleced during winter and then used to study chilling stress alleviation in tomato plants (Solanum lycopersicum cv Mill). Selective isolation after enrichment at 5°C yielded 40 bacterial isolates. Phylogenetic studies indicated their distribution in genera Arthrobacter, Flavimonas, Flavobacterium, Massilia, Pedobacter and Pseudomonas. Strains OS211, OB146, OB155 and OS261 consistently improved germination and plant growth when a chilling stress of 15°C was imposed and therefore were selected for pot experiments. Tomato plants treated with the selected four isolates exhibited significant tolerance to chilling as observed through reduction in membrane damage and activation of antioxidant enzymes along with proline synthesis in the leaves when exposed to chilling temperature conditions (15°C). Psychrotolerant physiology of the isolated bacteria combined with their ability to improve germination, plant growth and induce antioxidant capacity in tomato plants can be employed to protect plants against chilling stress. PMID:27580055

Application of alkaliphilic biofilm-forming bacteria to improve compressive strength of cement-sand mortar.

PubMed

Park, Sung-Jin; Chun, Woo-Young; Kim, Wha-Jung; Ghim, Sa-Youl

2012-03-01

The application of microorganisms in the field of construction material is rapidly increasing worldwide; however, almost all studies that were investigated were bacterial sources with mineral-producing activity and not with organic substances. The difference in the efficiency of using bacteria as an organic agent is that it could improve the durability of cement material. This study aimed to assess the use of biofilm-forming microorganisms as binding agents to increase the compressive strength of cement-sand material. We isolated 13 alkaliphilic biofilmforming bacteria (ABB) from a cement tetrapod block in the West Sea, Korea. Using 16S RNA sequence analysis, the ABB were partially identified as Bacillus algicola KNUC501 and Exiguobacterium marinum KNUC513. KNUC513 was selected for further study following analysis of pH and biofilm formation. Cement-sand mortar cubes containing KNUC513 exhibited greater compressive strength than mineral-forming bacteria (Sporosarcina pasteurii and Arthrobacter crystallopoietes KNUC403). To determine the biofilm effect, Dnase I was used to suppress the biofilm formation of KNUC513. Field emission scanning electron microscopy image revealed the direct involvement of organic-inorganic substance in cement-sand mortar.

Calcite-forming bacteria for compressive strength improvement in mortar.

PubMed

Park, Sung-Jin; Park, Yu-Mi; Chun, Woo-Young; Kim, Wha-Jung; Ghim, Sa-Youl

2010-04-01

Microbiological calcium carbonate precipitation (MCP) has been investigated for its ability to improve the compressive strength of concrete mortar. However, very few studies have been conducted on the use of calcite-forming bacteria (CFB) to improve compressive strength. In this study, we discovered new bacterial genera that are capable of improving the compressive strength of concrete mortar. We isolated 4 CFB from 7 environmental concrete structures. Using sequence analysis of the 16S rRNA genes, the CFB could be partially identified as Sporosarcina soli KNUC401, Bacillus massiliensis KNUC402, Arthrobacter crystallopoietes KNUC403, and Lysinibacillus fusiformis KNUC404. Crystal aggregates were apparent in the bacterial colonies grown on an agar medium. Stereomicroscopy, scanning electron microscopy, and x-ray diffraction analyses illustrated both the crystal growth and the crystalline structure of the CaCO3 crystals. We used the isolates to improve the compressive strength of concrete mortar cubes and found that KNUC403 offered the best improvement in compressive strength.

Synergistic effects of Candida and Escherichia coli on gut barrier function.

PubMed

Diebel, L N; Liberati, D M; Diglio, C A; Dulchavsky, S A; Brown, W J

1999-12-01

Disruption of the indigenous gut microflora with overgrowth of gram-negative bacteria and Candida species is common in the critically ill patient. These organisms readily translocate in vitro, which may cause septic complications and organ failure. A synergistic effect between Escherichia coli and C. albicans in polymicrobial infections has been demonstrated. An interaction between these organisms at the mucosal barrier is unknown. Ca(CO2) monolayers were grown to confluence in a two compartment culture system. E. coli and C. albicans or E. coli alone were added to the apical chambers. Secretory immunoglobulin A was added to half of the apical chambers as well. Cell cultures were incubated for a total of 240 minutes. Basal media were sampled at timed intervals for quantitative culture. Monolayer integrity was confirmed by serial measurement of transepithelial electrical resistance. Secretory immunoglobulin A decreased bacterial translocation across Ca(CO2) monolayers challenged with E. coli alone. Transepithelial passage of E. coli was significantly increased by coculture of bacteria with C. albicans. Augmentation of bacterial translocation by Candida occurred even in the presence of secretory immunoglobulin A. Candida colonization of the GI tract may impair mucosal barrier defense against gram-negative bacteria. The clinical role of gut antifungal prophylaxis in protecting against gut derived gram-negative sepsis is speculative.

What Healthcare Workers Should Know about Environmental Bacterial Contamination in the Intensive Care Unit.

PubMed

Russotto, Vincenzo; Cortegiani, Andrea; Fasciana, Teresa; Iozzo, Pasquale; Raineri, Santi Maurizio; Gregoretti, Cesare; Giammanco, Anna; Giarratano, Antonino

2017-01-01

Intensive care unit- (ICU-) acquired infections are a major health problem worldwide. Inanimate surfaces and equipment contamination may play a role in cross-transmission of pathogens and subsequent patient colonization or infection. Bacteria contaminate inanimate surfaces and equipment of the patient zone and healthcare area, generating a reservoir of potential pathogens, including multidrug resistant species. Traditional terminal cleaning methods have limitations. Indeed patients who receive a bed from prior patient carrying bacteria are exposed to an increased risk (odds ratio 2.13, 95% confidence intervals 1.62-2.81) of being colonized and potentially infected by the same bacterial species of the previous patient. Biofilm formation, even on dry surfaces, may play a role in reducing the efficacy of terminal cleaning procedures since it enables bacteria to survive in the environment for a long period and provides increased resistance to commonly used disinfectants. No-touch methods (e.g., UV-light, hydrogen peroxide vapour) are under investigation and further studies with patient-centred outcomes are needed, before considering them the standard of terminal cleaning in ICUs. Healthcare workers should be aware of the role of environmental contamination in the ICU and consider it in the broader perspective of infection control measures and stewardship initiatives.

Antibacterial effect of royal jelly for preservation of implant-related spinal infection in rat.

PubMed

Gunaldi, Omur; Daglioglu, Yusuf Kenan; Tugcu, Bekir; Kizilyildirim, Suna; Postalci, Lutfi; Ofluoglu, Ender; Koksal, Fatih

2014-01-01

Implant-related infections are still a significant problem in spinal surgical procedures. Many drugs and methods have been tried to prevent implant-related infections. Our objective in this study was to evaluate whether royal jelly, which was found to hinder the growth of MRSA, has any preventive role in the prognosis of an infection in rats in an implant-related infection model. Rats were divided into 3 groups of eight rats. Group-1 consisted of rats that underwent only a spinal implant, group-2 included those rats that were inoculated bacteria together with a spinal implant and group-3 was administered royal jelly in addition to a spinal implant and infection. The amount of bacteria that grew in vertebral columns and implants was more in Group-2 than in Group-3, which meant that the number of bacteria colonies that grew was more quantitatively. This difference was found to be statistically significant in vertebral columns, but not in implants. Royal jelly could not fully prevent the MRSA infection in this model, but decreased the severity of infection noticeably. More objective and promising results may be obtained if royal jelly can be used at regular intervals in a different model to be designed with respect to implant-related infections.

Microbiological evaluation of octenidine dihydrochloride mouth rinse after 5 days' use in orthodontic patients.

PubMed

Dogan, Alev Aksoy; Cetin, Emel Sesli; Hüssein, Emad; Adiloglu, Ali Kudret

2009-07-01

To determine the absolute and relative antibacterial activity of octenidine dihydrochloride (OCT) against total and cariogenic bacteria in saliva samples of patients with fixed orthodontic appliances during 5 days of usage. The study group consisted of 5 male and 13 female subjects who were selected from patients in the Clinic of Orthodontics. Each patient was given physiologic saline (PS), chlorhexidine gluconate (CHX), polyvinylpyrrolidone-iodine complex (PVP-I), and OCT every morning for 5 days, each separated by a 2-week interval. Total and cariogenic bacteria in saliva samples of orthodontically treated patients with fixed appliances were collected during 5 days of usage. Unstimulated saliva was collected as a baseline sample. Saliva samples were collected at 15 minutes, and on the second, third, and fifth day after rinsing the mouth with any of the solutions for 30 seconds, and bacterial counts were detected. OCT showed an ultimate reduction of total viable oral bacteria, Lactobacillus species, and Streptococcus mutans in vivo. OCT also had a significantly greater inhibitory effect than 0.2% CHX and 7.5% PVP-I, from the beginning of the study until the fifth day after the orthodontic appliances were bonded (P < .1). OCT compared favorably with respect to CHX and PVP-I complex in orthodontically treated patients with fixed appliances (P

Short-Term Results in Evaluating a Gingiva-Adhesive Hydrophobic-Chlorhexidine-Gel for Chronic Periodontitis

PubMed Central

SARBU, CIPRIAN; RUSU, DARIAN; CĂLNICEANU, HORIA; KASAJ, ADRIAN; PETRUTIU, STEFAN ADRIAN; ROMAN, ALEXANDRA; SOANCĂ, ANDRADA; PICOȘ, ALINA; STRATUL, STEFAN IOAN; JENTSCH, HOLGER

2014-01-01

Background and Aims: Oral mucosa and interproximal spaces of the teeth could favor the colonization of periodontopathogenic bacteria, which could be targeted by chemical antiplaque agents such as chlorhexidine, present in different oral hygiene products, thus improving the control of biofilm growth and delaying microbial accumulation. The study aimed to evaluate whether the use of a hydrophobic gel with good gingival adhesion for 14 days after the scaling and root planing of patients with chronic periodontitis would improve the treatment outcome, when compared with the use of a regular hydrophyllic gel. Material and Methods: Patients with moderate disease were included in two study groups. At baseline and 3 months after the treatment the following parameters were recorded: pocket depth, Approximal Plaque Index, Modified Gingival Index, Simplified Oral Hygiene Index, bleeding on probing. Patients received scaling and root planing in two sessions at 24 hours interval. After the treatment, patients in the test group applied the hydrophobic adhesive chlorhexidine gel once a day, every other day, while in the control group the gel was used twice daily. Results: Both treatments resulted in significant improvement in all clinical indices, except Approximal Plaque Index, which deteriorated significantly in both groups. Three months after mechanical treatment, the mean probing depth changed in the test group from 4.16±0.45 mm to 2.80±0.42 mm, and in the control group from 4.16±0.30 to 2.69±0.19. Conclusions: Both adjunctive anti-infective therapies induced clinical improvement 3 months from baseline. The differences between the two treatments were not statistically significant. PMID:26528022

Synthesis, Characterization, and In Vivo Efficacy of Shell Cross-Linked Nanoparticle Formulations Carrying Silver Antimicrobials as Aerosolized Therapeutics

PubMed Central

2014-01-01

The use of nebulizable, nanoparticle-based antimicrobial delivery systems can improve efficacy and reduce toxicity for treatment of multi-drug-resistant bacteria in the chronically infected lungs of cystic fibrosis patients. Nanoparticle vehicles are particularly useful for applying broad-spectrum silver-based antimicrobials, for instance, to improve the residence time of small-molecule silver carbene complexes (SCCs) within the lung. Therefore, we have synthesized multifunctional, shell cross-linked knedel-like polymeric nanoparticles (SCK NPs) and capitalized on the ability to independently load the shell and core with silver-based antimicrobial agents. We formulated three silver-loaded variants of SCK NPs: shell-loaded with silver cations, core-loaded with SCC10, and combined loading of shell silver cations and core SCC10. All three formulations provided a sustained delivery of silver over the course of at least 2–4 days. The two SCK NP formulations with SCC10 loaded in the core each exhibited excellent antimicrobial activity and efficacy in vivo in a mouse model of Pseudomonas aeruginosa pneumonia. SCK NPs with shell silver cation-load only, while efficacious in vitro, failed to demonstrate efficacy in vivo. However, a single dose of core SCC10-loaded SCK NPs (0.74 ± 0.16 mg Ag) provided a 28% survival advantage over sham treatment, and administration of two doses (0.88 mg Ag) improved survival to 60%. In contrast, a total of 14.5 mg of Ag+ delivered over 5 doses at 12 h intervals was necessary to achieve a 60% survival advantage with a free-drug (SCC1) formulation. Thus, SCK NPs show promise for clinical impact by greatly reducing antimicrobial dosage and dosing frequency, which could minimize toxicity and improve patient adherence. PMID:23718195

Detection of antimicrobial resistance-associated proteins by titanium dioxide-facilitated intact bacteria mass spectrometry† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc04089j

PubMed Central

Zhu, Yingdi; Gasilova, Natalia; Jović, Milica; Qiao, Liang; Liu, Baohong; Lovey, Lysiane Tissières; Pick, Horst

2018-01-01

Titanium dioxide-modified target plates were developed to enhance intact bacteria analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The plates were designed to photocatalytically destroy the bacterial envelope structure and improve the ionization efficiency of intracellular components, thereby promoting the measurable mass range and the achievable detection sensitivity. Accordingly, a method for rapid detection of antimicrobial resistance-associated proteins, conferring bacterial resistance against antimicrobial drugs, was established by mass spectrometric fingerprinting of intact bacteria without the need for any sample pre-treatment. With this method, the variations in resistance proteins’ expression levels within bacteria were quickly measured from the relative peak intensities. This approach of resistance protein detection directly from intact bacteria by mass spectrometry is useful for fast discrimination of antimicrobial-resistant bacteria from their non-resistant counterparts whilst performing species identification. Also, it could be used as a rapid and convenient way for initial determination of the underlying resistance mechanisms. PMID:29719694

High-volume extraction of nucleic acids by magnetic bead technology for ultrasensitive detection of bacteria in blood components.

PubMed

Störmer, Melanie; Kleesiek, Knut; Dreier, Jens

2007-01-01

Nucleic acid isolation, the most technically demanding and laborious procedure performed in molecular diagnostics, harbors the potential for improvements in automation. A recent development is the use of magnetic beads covered with nucleic acid-binding matrices. We adapted this technology with a broad-range 23S rRNA real-time reverse transcription (RT)-PCR assay for fast and sensitive detection of bacterial contamination of blood products. We investigated different protocols for an automated high-volume extraction method based on magnetic-separation technology for the extraction of bacterial nucleic acids from platelet concentrates (PCs). We added 2 model bacteria, Staphylococcus epidermidis and Escherichia coli, to a single pool of apheresis-derived, single-donor platelets and assayed the PCs by real-time RT-PCR analysis with an improved primer-probe system and locked nucleic acid technology. Co-amplification of human beta(2)-microglobulin mRNA served as an internal control (IC). We used probit analysis to calculate the minimum concentration of bacteria that would be detected with 95% confidence. For automated magnetic bead-based extraction technology with the real-time RT-PCR, the 95% detection limit was 29 x 10(3) colony-forming units (CFU)/L for S. epidermidis and 22 x 10(3) CFU/L for E. coli. No false-positive results occurred, either due to nucleic acid contamination of reagents or externally during testing of 1030 PCs. High-volume nucleic acid extraction improved the detection limit of the assay. The improvement of the primer-probe system and the integration of an IC make the RT-PCR assay appropriate for bacteria screening of platelets.

Lensfree in-line holographic detection of bacteria

NASA Astrophysics Data System (ADS)

Poher, V.; Allier, C. P.; Coutard, J. G.; Hervé, L.; Dinten, J. M.

2011-07-01

Due to low light scattering, bacteria are difficult to detect using lensless imaging systems. In order to detect individual bacteria, we report a method based on a thin wetting film imaging that produces a micro-lens effect on top of each bacterium when the sample dries up. The imaging using a high-end CMOS sensor is combined with an in-line holographic reconstruction to improve positive detection rate up to 95% with micron-sized beads at high density of ~103 objects/mm2. The system allows detecting from single bacterium to densely packed objects (103 bacteria/μl) within 10μl sample. As an example, E.coli, Bacillus subtilis and Bacillus thuringiensis, has been successfully detected with strong signal to noise ratio across a 24mm2 field of view.

Improving stethoscope disinfection at a children's hospital.

PubMed

Zaghi, Justin; Zhou, Jing; Graham, Dionne A; Potter-Bynoe, Gail; Sandora, Thomas J

2013-11-01

Stethoscopes are contaminated with pathogenic bacteria and pose a risk for transmission of infections, but few clinicians disinfect their stethoscope after every use. We sought to improve stethoscope disinfection rates among pediatric healthcare providers by providing access to disinfection materials and visual reminders to disinfect stethoscopes. Prospective intervention study. Inpatient units and emergency department of a major pediatric hospital. Physicians and nurses with high anticipated stethoscope use. Baskets filled with alcohol prep pads and a sticker reminding providers to regularly disinfect stethoscopes were installed outside of patient rooms. Healthcare providers' stethoscope disinfection behaviors were directly observed before and after the intervention. Multivariable logistic regression models were created to identify independent predictors of stethoscope disinfection. Two hundred twenty-six observations were made in the preintervention period and 261 in the postintervention period (83% were of physicians). Stethoscope disinfection compliance increased significantly from a baseline of 34% to 59% postintervention (P < .001). In adjusted analyses, the postintervention period was associated with improved disinfection among both physicians (odds ratio [OR], 2.3 [95% confidence interval (CI), 1.4-3.5]) and nurses (OR, 14.3 [95% CI, 4.6-44.6]). Additional factors independently associated with disinfection included subspecialty unit (vs general pediatrics; OR, 0.5 [95% CI, 0.3-0.8]) and contact precautions (OR, 2.3 [95% CI, 1.2-4.1]). Providing stethoscope disinfection supplies and visible reminders outside of patient rooms significantly increased stethoscope disinfection rates among physicians and nurses at a children's hospital. This simple intervention could be replicated at other healthcare facilities. Future research should assess the impact on patient infections.

Predictive modelling of a novel anti-adhesion therapy to combat bacterial colonisation of burn wounds

PubMed Central

Huebinger, Ryan M.; Keen, Emma

2018-01-01

As the development of new classes of antibiotics slows, bacterial resistance to existing antibiotics is becoming an increasing problem. A potential solution is to develop treatment strategies with an alternative mode of action. We consider one such strategy: anti-adhesion therapy. Whereas antibiotics act directly upon bacteria, either killing them or inhibiting their growth, anti-adhesion therapy impedes the binding of bacteria to host cells. This prevents bacteria from deploying their arsenal of virulence mechanisms, while simultaneously rendering them more susceptible to natural and artificial clearance. In this paper, we consider a particular form of anti-adhesion therapy, involving biomimetic multivalent adhesion molecule 7 coupled polystyrene microbeads, which competitively inhibit the binding of bacteria to host cells. We develop a mathematical model, formulated as a system of ordinary differential equations, to describe inhibitor treatment of a Pseudomonas aeruginosa burn wound infection in the rat. Benchmarking our model against in vivo data from an ongoing experimental programme, we use the model to explain bacteria population dynamics and to predict the efficacy of a range of treatment strategies, with the aim of improving treatment outcome. The model consists of two physical compartments: the host cells and the exudate. It is found that, when effective in reducing the bacterial burden, inhibitor treatment operates both by preventing bacteria from binding to the host cells and by reducing the flux of daughter cells from the host cells into the exudate. Our model predicts that inhibitor treatment cannot eliminate the bacterial burden when used in isolation; however, when combined with regular or continuous debridement of the exudate, elimination is theoretically possible. Lastly, we present ways to improve therapeutic efficacy, as predicted by our mathematical model. PMID:29723210

[Community Characteristics of ANAMMOX Bacteria in Subsurface Flow Constructed Wetland (SSFCW) for Processing of Aquaculture Waster Water].

PubMed

Zeng, Xian-lei; Liu, Xing-guo; Wu, Zong-fan; Shi, Xu; Lu, Shi-min

2016-02-15

Anaerobic ammonium oxidation (ANAMMOX) is one of the important functions in waste water treatment by subsurface flow constructed wetland (SSFCW), however, there are few studies on ANAMMOX in SSFCW environment at present. The community characteristics of ANAMMOX in the SSFCW of processing aquaculture waste water were explored in this study. In order to analyze the structure, diversity and abundance of ANAMMOX bacteria, several 16S rRNA clone libraries were constructed and real-time PCR targeting specific 16S rRNA genes together with diversity analysis was adopted. The obtained results showed that the SSFCW identified a total of three unknown clusters and two known clusters including Candidatus brocadia and Candidatus kuenenia. The dominant cluster was Candidatus brocadia. The highest diversity levels of ANAMMOX bacteria occurred in autumn (H', 1.21), while the lowest in spring (H', 0.64). The abundance of ANAMMOX bacteria in SSFCW environment ranged from 8.0 x 10(4) to 9.4 x 10(6) copies x g(-1) of fresh weight and the copy number of total bacterial 16S rRNA genes ranged from 7.3 x 10(9) to 9.1 x 10(10) copies x g(-1) of fresh weight during culture cycle. There were significant differences in the ANAMMOX bacteria abundances of different stratum and seasons in SSFCW environment, but the differences in total bacterial abundances were not obvious. In addition, the differences in ANAMMOX bacteria abundances in different stratum and seasons in SSFCW environment were irregular in different culture cycle. According to the distribution characteristics of ANAMMOX bacteria in the wetland, the denitrification effect of SSFCW could be improved by changing the supplying manners of aquaculture wastewater and adjusting the structure of wetland. The research results will provide reference for further optimizing the SSFCW and improving the efficiency of purification.

Added value of experts' knowledge to improve a quantitative microbial exposure assessment model--Application to aseptic-UHT food products.

PubMed

Pujol, Laure; Johnson, Nicholas Brian; Magras, Catherine; Albert, Isabelle; Membré, Jeanne-Marie

2015-10-15

In a previous study, a quantitative microbial exposure assessment (QMEA) model applied to an aseptic-UHT food process was developed [Pujol, L., Albert, I., Magras, C., Johnson, N. B., Membré, J. M. Probabilistic exposure assessment model to estimate aseptic UHT product failure rate. 2015 International Journal of Food Microbiology. 192, 124-141]. It quantified Sterility Failure Rate (SFR) associated with Bacillus cereus and Geobacillus stearothermophilus per process module (nine modules in total from raw material reception to end-product storage). Previously, the probabilistic model inputs were set by experts (using knowledge and in-house data). However, only the variability dimension was taken into account. The model was then improved using expert elicitation knowledge in two ways. First, the model was refined by adding the uncertainty dimension to the probabilistic inputs, enabling to set a second order Monte Carlo analysis. The eight following inputs, and their impact on SFR, are presented in detail in this present study: D-value for each bacteria of interest (B. cereus and G. stearothermophilus) associated with the inactivation model for the UHT treatment step, i.e., two inputs; log reduction (decimal reduction) number associated with the inactivation model for the packaging sterilization step for each bacterium and each part of the packaging (product container and sealing component), i.e., four inputs; and bacterial spore air load of the aseptic tank and the filler cabinet rooms, i.e., two inputs. Second, the model was improved by leveraging expert knowledge to develop further the existing model. The proportion of bacteria in the product which settled on surface of pipes (between the UHT treatment and the aseptic tank on one hand, and between the aseptic tank and the filler cabinet on the other hand) leading to a possible biofilm formation for each bacterium, was better characterized. It was modeled as a function of the hygienic design level of the aseptic-UHT line: the experts provided the model structure and most of the model parameters values. Mean of SFR was estimated to 10×10(-8) (95% Confidence Interval=[0×10(-8); 350×10(-8)]) and 570×10(-8) (95% CI=[380×10(-8); 820×10(-8)]) for B. cereus and G. stearothermophilus, respectively. These estimations were more accurate (since the confidence interval was provided) than those given by the model with only variability (for which the estimates were 15×10(-8) and 580×10(-8) for B. cereus and G. stearothermophilus, respectively). The updated model outputs were also compared with those obtained when inputs were described by a generic distribution, without specific information related to the case-study. Results showed that using a generic distribution can lead to unrealistic estimations (e.g., 3,181,000 product units contaminated by G. stearothermophilus among 10(8) product units produced) and emphasized the added value of eliciting information from experts from the relevant specialist field knowledge. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantification of spatial distribution and spread of bacteria in soil at microscale

NASA Astrophysics Data System (ADS)

Juyal, Archana; Eickhorst, Thilo; Falconer, Ruth; Baveye, Philippe; Otten, Wilfred

2015-04-01

Soil bacteria play an essential role in functioning of ecosystems and maintaining of biogeochemical cycles. Soil is a complex heterogeneous environment comprising of highly variable and dynamic micro-habitats that have significant impacts on the growth and activity of resident microbiota including bacteria and fungi. Bacteria occupy a very small portion of available pore space in soil which demonstrates that their spatial arrangement in soil has a huge impact on the contact to their target and on the way they interact to carry out their functions. Due to limitation of techniques, there is scant information on spatial distribution of indigenous or introduced bacteria at microhabitat scale. There is a need to understand the interaction between soil structure and microorganisms including fungi for ecosystem-level processes such as carbon sequestration and improving the predictive models for soil management. In this work, a combination of techniques was used including X-ray CT to characterize the soil structure and in-situ detection via fluorescence microscopy to visualize and quantify bacteria in soil thin sections. Pseudomonas fluorescens bacteria were introduced in sterilized soil of aggregate size 1-2 mm and packed at bulk-densities 1.3 g cm-3 and 1.5 g cm-3. A subset of samples was fixed with paraformaldehyde and subsequently impregnated with resin. DAPI and fluorescence in situ hybridization (FISH) were used to visualize bacteria in thin sections of soil cores by epifluorescence microscopy to enumerate spatial distribution of bacteria in soil. The pore geometry of soil was quantified after X-ray microtomography scanning. The distribution of bacteria introduced locally reduced significantly (P

Stratifying risk factors for multidrug-resistant pathogens in hospitalized patients coming from the community with pneumonia.

PubMed

Aliberti, Stefano; Di Pasquale, Marta; Zanaboni, Anna Maria; Cosentini, Roberto; Brambilla, Anna Maria; Seghezzi, Sonia; Tarsia, Paolo; Mantero, Marco; Blasi, Francesco

2012-02-15

 Not all risk factors for acquiring multidrug-resistant (MDR) organisms are equivalent in predicting pneumonia caused by resistant pathogens in the community. We evaluated risk factors for acquiring MDR bacteria in patients coming from the community who were hospitalized with pneumonia. Our evaluation was based on actual infection with a resistant pathogen and clinical outcome during hospitalization.  An observational, prospective study was conducted on consecutive patients coming from the community who were hospitalized with pneumonia. Data on admission and during hospitalization were collected. Logistic regression models were used to evaluate risk factors for acquiring MDR bacteria independently associated with the actual presence of a resistant pathogen and in-hospital mortality.  Among the 935 patients enrolled in the study, 473 (51%) had at least 1 risk factor for acquiring MDR bacteria on admission. Of all risk factors, hospitalization in the preceding 90 days (odds ratio [OR], 4.87 95% confidence interval {CI}, 1.90-12.4]; P = .001) and residency in a nursing home (OR, 3.55 [95% CI, 1.12-11.24]; P = .031) were independent predictors for an actual infection with a resistant pathogen. A score able to predict pneumonia caused by a resistant pathogen was computed, including comorbidities and risk factors for MDR. Hospitalization in the preceding 90 days and residency in a nursing home were also independent predictors for in-hospital mortality.  Risk factors for acquiring MDR bacteria should be weighted differently, and a probabilistic approach to identifying resistant pathogens among patients coming from the community with pneumonia should be embraced.

Significance of Microbial Communities and Interactions in Safeguarding Reactive Mine Tailings by Ecological Engineering▿†

PubMed Central

N̆ancucheo, Ivan; Johnson, D. Barrie

2011-01-01

Pyritic mine tailings (mineral waste generated by metal mining) pose significant risk to the environment as point sources of acidic, metal-rich effluents (acid mine drainage [AMD]). While the accelerated oxidative dissolution of pyrite and other sulfide minerals in tailings by acidophilic chemolithotrophic prokaryotes has been widely reported, other acidophiles (heterotrophic bacteria that catalyze the dissimilatory reduction of iron and sulfur) can reverse the reactions involved in AMD genesis, and these have been implicated in the “natural attenuation” of mine waters. We have investigated whether by manipulating microbial communities in tailings (inoculating with iron- and sulfur-reducing acidophilic bacteria and phototrophic acidophilic microalgae) it is possible to mitigate the impact of the acid-generating and metal-mobilizing chemolithotrophic prokaryotes that are indigenous to tailing deposits. Sixty tailings mesocosms were set up, using five different microbial inoculation variants, and analyzed at regular intervals for changes in physicochemical and microbiological parameters for up to 1 year. Differences between treatment protocols were most apparent between tailings that had been inoculated with acidophilic algae in addition to aerobic and anaerobic heterotrophic bacteria and those that had been inoculated with only pyrite-oxidizing chemolithotrophs; these differences included higher pH values, lower redox potentials, and smaller concentrations of soluble copper and zinc. The results suggest that empirical ecological engineering of tailing lagoons to promote the growth and activities of iron- and sulfate-reducing bacteria could minimize their risk of AMD production and that the heterotrophic populations could be sustained by facilitating the growth of microalgae to provide continuous inputs of organic carbon. PMID:21965397

Marked Liver Tumorigenesis by Helicobacter hepaticus Requires Perinatal Exposure

PubMed Central

Diwan, Bhalchandra A.; Sipowicz, Marek; Logsdon, Daniel; Gorelick, Peter; Anver, Miriam R.; Kasprzak, Kazimierz S.; Anderson, Lucy M.

2008-01-01

Background Although severe hepatitis and liver tumors occur in a high percentage of A/J male mice naturally infected with Helicobacter hepaticus, these effects have not been observed after injection of adult mice with the bacteria. Objectives We tested the hypothesis that perinatal exposure to the bacteria is required for liver tumorigenesis. Methods A/J female mice were infected by intragastric (ig) or intraperitoneal (ip) treatment with 1.5 × 108 H. hepaticus before pregnancy. We examined offspring at progressive time intervals, including some kept until natural death in old age. A/J, BALB/c, and C57BL/6 weanling male mice were similarly treated ig with the bacteria and observed for up to 2 years. Results After ip bacterial infection of A/J females, 41% of their male offspring developed hepatitis and 33% had hepatocellular tumors, including 18% with hepatocellular carcinoma. Treatment by the ig route resulted in a similar incidence of hepatitis in offspring (35%) but fewer total liver tumors (8%) and carcinomas (4%). By contrast, ig instillation of H. hepaticus in weanling A/J, C57BL/6, or BALB/c mice resulted in low incidence of hepatitis (0–20%) and few liver tumors, despite presence of bacteria confirmed in feces. Conclusions Results indicate that a high incidence of liver tumors in mice infected with H. hepaticus requires perinatal exposure. Contributing perinatal factors could include known high sensitivity of neonatal liver to tumor initiation, and/or modulation of immune response to the bacterium or its toxins. Mechanisms of human perinatal sensitivity to such phenomena can be studied with this model. PMID:18941577

Phytoplankton and bacterial community structures and their interaction during red-tide phenomena

NASA Astrophysics Data System (ADS)

Ismail, Mona Mohamed; Ibrahim, Hassan Abd Allah

2017-09-01

Phytoplankton and bacteria diversity were studied before, during and after red tide phenomena during spring season 2015 in the Eastern Harbour (E.H.) of Alexandria, Egypt. Fifty five species of phytoplankton were identified and represented different distinct classes "Bacillariophyceae; Dinophyceae, Chlorophyceae, Cyanophyceae and Eugelenophyceae". Also, Diatom formed the most dominant group. The average number of the phytoplankton density varied from 4.8 × 104 to 1.1 × 106 cell l-1 during the study period and Skeletonema costatum was the agent causing the red tide. The existence percentages of bacteria ranged from 2.6 to 17.9% on all media tested. The bacterial isolates on the nutrient agar medium represented the highest existence with a total percentage of 43.6%, followed by MSA medium (25.7%), while the lowest percentage was for the AA medium at 7.8%. However, twelve isolates were selected as representative for bacterial community during study interval. Based on the morphological, biochemical, physiological and enzymatic characteristics, the bacterial strains were described. Depending on the 16S rDNA gene sequence, three common antagonists were aligned as: Vibrio toranzoniae strain Vb 10.8, Ruegeria pelagia strain NBRC 102038 and Psychrobacter adeliensis strain DSM 15333. The interaction between these bacteria and S. costatum was studied. The growth of S. costatum was significantly lower whenever each bacterium was present as compared to axenic culture. More specifically, 30% (v/v) of the all tested bacteria showed the strongest algicidal activities, as all S. costatum cells were killed after two days. 10% of R. pelagia and P. adeliensis also showed significant algicidal activities within six days.

The abundance and diversity of heterotrophic bacteria as a function of harvesting frequency of duckweed (Lemna minor L.) in recirculating aquaculture systems.

PubMed

Ardiansyah, A; Fotedar, R

2016-07-01

Duckweed (Lemna minor L.) is a potential biofilter for nutrient removal and acts as a substrate for heterotrophic bacteria in recirculating aquaculture systems (RAS). Here, we determined the effects of harvesting frequency of duckweed on heterotrophic bacteria in RAS. Twelve independent RAS consisting of fish-rearing tank, biofilter tank and waste-collection tank were used to study the interactions between duckweed harvest frequencies up to 6 days and the composition, abundance and diversity of heterotrophic bacteria. After 36 days, heterotrophic bacteria in the biofilter tank were primarily Gram-negative cocci or ovoid, coccobacilli, Gram-negative bacilli and Gram-positive bacilli. Most bacterial genera were Bacillus and Pseudomonas while the least common was Acinetobacter. Duckweed harvested after every 2 days produced the highest specific growth rates (SGR) and total harvested biomass of duckweed, but harboured less abundant bacteria, whereas 6-day harvests had a higher growth index (GI) of duckweed than 2-day harvests, but caused a poor relationship between SGR and biomass harvest with the abundance and diversity of heterotrophic bacteria. Stronger correlations (R(2)  > 0·65) between duckweed SGR and biomass harvest with the heterotrophic bacteria diversity were observed at 4-day harvest frequency and the control. This study provides significant information on the interaction between the harvest frequency of duckweed and the composition, abundance and diversity of heterotrophic bacteria in recirculating aquaculture systems (RAS). Different harvest frequencies significantly influence the abundance and diversity of heterotrophic bacteria, which in turn may influence the nitrogen uptake efficiency of the system. The research is useful in improving the efficiency of removing nitrogenous metabolites in RAS directly by the duckweed and associated heterotrophic bacteria. © 2016 The Society for Applied Microbiology.

Processing of cellulosic material by a cellulase-containing cell-free fermentate produced from cellulase-producing bacteria, ATCC 55702

DOEpatents

Dees, H.C.

1998-08-04

Bacteria which produce large amounts of a cellulase-containing cell-free fermentate, have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase degrading bacterium ATCC 55702, which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic materials. 5 figs.

Processing of cellulosic material by a cellulase-containing cell-free fermentate produced from cellulase-producing bacteria, ATCC 55702

DOEpatents

Dees, H. Craig

1998-01-01

Bacteria which produce large amounts of a cellulase-containing cell-free fermentate, have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase degrading bacterium ATCC 55702, which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic materials.

Biocompatability of compomer restorative systems on nonexposed dental pulps of primate teeth.

PubMed

Tarim, B; Hafez, A A; Suzuki, S H; Suzuki, S; Cox, C F

1997-01-01

This study evaluated the histologic response of total-etched and nonetched compomer restored cavity preparations. One hundred fifteen class 5 cavity preparations were placed in the teeth of four healthy adult monkeys at 7, 27, and 90 days. A 37% H3PO4 was applied for 10 seconds and rinsed in total-etched preparations. No statistical differences were seen in inflammatory reactions among total-etched or nonetched compomers at 7, 27, and 90 days. There were no statistical differences in inflammatory cell responses among all compomer systems in regard to time intervals. Pulpal responses of compomers were greater than IRM at each time period. Pulp responses were associated with stained bacteria in 32 of 89 compomer teeth. No necrotic pulps were seen in any teeth. Statistical data show a positive correlation (P < 0.05) between bacterial presence and pulpal inflammation. IRM pulps showed no inflammation or bacterial staining. Compomers are biologically compatible with pulp tissues when bacteria are excluded.

Estimating growth rates of uncultivated clades of archaea and bacteria in marine sediments

NASA Astrophysics Data System (ADS)

Lloyd, K. G.

2016-12-01

The vast majority of microbes present in marine sediments have never been cultivated in laboratory conditions. It is therefore difficult to estimate the growth rates of these organisms in situ. Quantitative PCR (qPCR) and 16S rRNA gene libraries from sediments below 10 cm show very little change in abundance of these organisms with depth or with redox conditions. Therefore, we hypothesized that uncultivated clades of bacteria and archaea that are ubiquitous in marine sediments, actually grow in the upper 10 cm of marine sediments. We collected sediment cores from the White Oak River estuary, sectioned them in 1 cm intervals, and examined the changes in abundance of uncultivated microbes with depth using 16S rRNA gene libraries and qPCR. We found that some of the key clades associated with the deep subsurface microbiome, such as Bathyarchaeota and MBG-D, increase in abundance with depth, demonstrating extremely slow growth in these shallow subsurface sediments.

Ceria nanocubic-ultrasonication assisted dispersive liquid-liquid microextraction coupled with matrix assisted laser desorption/ionization mass spectrometry for pathogenic bacteria analysis.

PubMed

Abdelhamid, Hani Nasser; Bhaisare, Mukesh L; Wu, Hui-Fen

2014-03-01

A new ceria (CeO2) nanocubic modified surfactant is used as the basis of a novel nano-based microextraction technique for highly sensitive detection of pathogenic bacteria (Pseudomonas aeruginosa and Staphylococcus aureus). The technique uses ultrasound enhanced surfactant-assisted dispersive liquid-liquid microextraction (UESA-DLLME) with and without ceria (CeO2) followed by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS). In order to achieve high separation efficiency, we investigated the influential parameters, including extraction time of ultrasonication, type and volume of the extraction solvent and surfactant. Among various surfactants, the cationic surfactants can selectively offer better extraction efficiency on bacteria analysis than that of the anionic surfactants due to the negative charges of bacteria cell membranes. Extractions of the bacteria lysate from aqueous samples via UESA-DLLME-MALDI-MS were successfully achieved by using cetyltrimethyl ammonium bromide (CTAB, 10.0 µL, 1.0×10(-3) M) as surfactants in chlorobenzene (10.0 µL) and chloroform (10.0 µL) as the optimal extracting solvent for P. aeruginosa and S. aureus, respectively. Ceria nanocubic was synthesized, and functionalized with CTAB (CeO2@CTAB) and then characterized using transmission electron microscopy (TEM) and optical spectroscopy (UV and FTIR). CeO2@CTAB demonstrates high extraction efficiency, improve peaks ionization, and enhance resolution. The prime reasons for these improvements are due to the large surface area of nanoparticles, and its absorption that coincides with the wavelength of MALDI laser (337 nm, N2 laser). CeO2@CTAB-based microextraction offers lowest detectable concentrations tenfold lower than that of without nanoceria. The present approach has been successfully applied to detect pathogenic bacteria at low concentrations of 10(4)-10(5) cfu/mL (without ceria) and at 10(3)-10(4) cfu/mL (with ceria) from bacteria suspensions. Finally, the current approach was applied for analyzing the pathogenic bacteria in biological samples (blood and serum). Ceria assist surfactant (CeO2@CTAB) liquid-liquid microextraction (LLME) offers better extraction efficiency than that of using the surfactant in LLME alone. © 2013 Elsevier B.V. All rights reserved.

An optimized staining technique for the detection of Gram positive and Gram negative bacteria within tissue.

PubMed

Becerra, Sandra C; Roy, Daniel C; Sanchez, Carlos J; Christy, Robert J; Burmeister, David M

2016-04-12

Bacterial infections are a common clinical problem in both acute and chronic wounds. With growing concerns over antibiotic resistance, treatment of bacterial infections should only occur after positive diagnosis. Currently, diagnosis is delayed due to lengthy culturing methods which may also fail to identify the presence of bacteria. While newer costly bacterial identification methods are being explored, a simple and inexpensive diagnostic tool would aid in immediate and accurate treatments for bacterial infections. Histologically, hematoxylin and eosin (H&E) and Gram stains have been employed, but are far from optimal when analyzing tissue samples due to non-specific staining. The goal of the current study was to develop a modification of the Gram stain that enhances the contrast between bacteria and host tissue. A modified Gram stain was developed and tested as an alternative to Gram stain that improves the contrast between Gram positive bacteria, Gram negative bacteria and host tissue. Initially, clinically relevant strains of Pseudomonas aeruginosa and Staphylococcus aureus were visualized in vitro and in biopsies of infected, porcine burns using routine Gram stain, and immunohistochemistry techniques involving bacterial strain-specific fluorescent antibodies as validation tools. H&E and Gram stain of serial biopsy sections were then compared to a modification of the Gram stain incorporating a counterstain that highlights collagen found in tissue. The modified Gram stain clearly identified both Gram positive and Gram negative bacteria, and when compared to H&E or Gram stain alone provided excellent contrast between bacteria and non-viable burn eschar. Moreover, when applied to surgical biopsies from patients that underwent burn debridement this technique was able to clearly detect bacterial morphology within host tissue. We describe a modification of the Gram stain that provides improved contrast of Gram positive and Gram negative microorganisms within host tissue. The samples used in this study demonstrate that this staining technique has laboratory and clinical applicability. This modification only adds minutes to traditional Gram stain with reusable reagents, and results in a cost- and time-efficient technique for identifying bacteria in any clinical biopsy containing connective tissue.

Efficacy of biochar to remove Escherichia coli from stormwater under steady and intermittent flow.

PubMed

Mohanty, Sanjay K; Cantrell, Keri B; Nelson, Kara L; Boehm, Alexandria B

2014-09-15

Biofilters, designed to facilitate the infiltration of stormwater into soil, are generally ineffective in removing bacteria from stormwater, thereby causing pollution of groundwater and receiving surface waters. The bacterial removal capacity of biofilters has been shown to be lower in the presence of natural organic matter (NOM) and during intermittent infiltration of stormwater. To improve the removal of fecal indicator bacteria (Escherichia coli) under these conditions, we amended sand with 5% (by weight) biochar, a carbonaceous geomedia produced by pyrolysis of biomass, and investigated the removal and remobilization of E. coli. Three types of biochar were used to evaluate the role of biochar properties on the removal. Compared to sand, biochar not only retained up to 3 orders of magnitude more E. coli, but also prevented their mobilization during successive intermittent flows. In the presence of NOM, the removal capacity of biochar was lower, but remained higher than sand alone. The improved retention with the biochar amendment is attributed to an increase in the attachment of E. coli at the primary minimum and to an increase in the water-holding capacity of biochar-amended sand, which renders driving forces such as moving air-water interfaces less effective in detaching bacteria from grain surfaces. Biochars with lower volatile matter and polarity appear to be more effective in removing bacteria from stormwater. Overall, our results suggest that a biochar amendment to biofilter media has the potential to effectively remove bacteria from stormwater. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of Periodic Presumptive Treatment for Bacterial Vaginosis on the Vaginal Microbiome among Women Participating in the Preventing Vaginal Infections Trial

PubMed Central

Srinivasan, Sujatha; Anzala, Omu; Kimani, Joshua; Andac, Chloe; Schwebke, Jane; Fredricks, David N.; McClelland, R. Scott

2017-01-01

Abstract Background. Evidence suggests that specific vaginal bacteria associated with bacterial vaginosis (BV) may increase the risk of adverse health outcomes in women. Among women participating in a randomized, double-blinded trial, we assessed the effect of periodic presumptive treatment (PPT) on detection of select vaginal bacteria. Methods. High-risk women from the United States and Kenya with a recent vaginal infection received intravaginal metronidazole 750 mg plus miconazole 200 mg or placebo for 5 consecutive nights each month for 12 months. Vaginal fluid specimens were collected via polyester/polyethylene terephthalate swabs every other month and tested for bacteria, using quantitative polymerase chain reaction (PCR) assays targeting the 16S ribosomal RNA gene. The effect of PPT on bacterium detection was assessed among all participants and stratified by country. Results. Of 234 women enrolled, 221 had specimens available for analysis. The proportion of follow-up visits with detectable quantities was lower in the PPT arm versus the placebo arm for the following bacteria: BVAB1, BVAB2, Atopobium vaginae, Leptotrichia/Sneathia, and Megasphaera. The magnitude of reductions was greater among Kenyan participants as compared to US participants. Conclusions. Use of monthly PPT for 1 year reduced colonization with several bacteria strongly associated with BV. The role of PPT to improve vaginal health should be considered, and efforts to improve the impact of PPT regimens are warranted. PMID:28007924

Assessing the role of endophytic bacteria in the halophyte Arthrocnemum macrostachyum salt tolerance.

PubMed

Navarro-Torre, S; Barcia-Piedras, J M; Mateos-Naranjo, E; Redondo-Gómez, S; Camacho, M; Caviedes, M A; Pajuelo, E; Rodríguez-Llorente, I D

2017-03-01

There is an increasing interest to use halophytes for revegetation of salt affected ecosystems, as well as in understanding their mechanisms of salt tolerance. We hypothesized that bacteria from the phyllosphere of these plants might play a key role in its high tolerance to excessive salinity. Eight endophytic bacteria belonging to Bacillus and closely related genera were isolated from phyllosphere of the halophyte Arthrocnemum macrostachyum growing in salty agricultural soils. The presence of plant-growth promoting (PGP) properties, enzymatic activities and tolerance towards NaCl was determined. Effects of inoculation on seeds germination and adult plant growth under experimental NaCl treatments (0, 510 and 1030 mM NaCl) were studied. Inoculation with a consortium including the best performing bacteria improved considerably the kinetics of germination and the final germination percentage of A. macrostachyum seeds. At high NaCl concentrations (1030 mM), inoculation of plants mitigated the effects of high salinity on plant growth and physiological performance and, in addition, this consortium appears to have increased the potential of A. macrostachyum to accumulate Na + in its shoots, thus improving sodium phytoextraction capacity. Bacteria isolated from A. macrostachyum phyllosphere seem to play an important role in plant salt tolerance under stressing salt concentrations. The combined use of A. macrostachyum and its microbiome can be an adequate tool to enhance plant adaptation and sodium phytoextraction during restoration of salt degraded soils. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Effect of adaptation and pulp density on bioleaching of mine waste using indigenous acidophilic bacteria

NASA Astrophysics Data System (ADS)

Cho, K.; Kim, B.; Lee, D.; Choi, N.; Park, C.

2011-12-01

Adaptation to environment is a natural phenomena that takes place in many animals, plants and microorganisms. These adapted organisms achieve stronger applicability than unadapted organisms after habitation in a specific environment for a long time. In the biohydrometallurgical industry, adaptation to special environment conditions by selective culturing is the most popular method for improving bioleaching activity of strains-although that is time consuming. This study investigated the influence of the bioleaching efficiency of mine waste under batch experimental conditions (adaptation and pulp density) using the indigenous acidophilic bacteria collected from acid mine drainage in Go-seong and Yeon-hwa, Korea. We conducted the batch experiments at the influences of parameters, such as the adaptation of bacteria and pulp density of the mine waste. In the adaptation case, the value of pH in 1'st adaptation bacteria sample exhibited lower than in 2'nd adaptation bacteria sample. And the content of both Cu and Zn at 1'st adaptation bacteria sample appeared lower than at 2'nd adaptation bacteria sample. In the SEM analysis, the rod-shaped bacteria with 1μm in length were observed on the filter paper (pore size - 0.45μm). The results of pulp density experiments revealed that the content of both Cu and Zn increased with increasing pulp density, since the increment of pulp density resulted in the enhancement of bioleaching capacity.

The role of latex agglutination test for the etiological diagnosis of pleural effusion in children and adolescents.

PubMed

Camargos, Paulo; Fonseca, Ana Cristina; Amantéa, Sérgio; Oliveira, Elizabeth; Benfica, Maria das Graças; Chamone, Chequer

2017-05-01

The etiological diagnosis of pleural effusion is a difficult task because the diagnostic tools can only establish a definitive etiological diagnosis in at most 76% of cases. To verify the diagnostic accuracy of the latex agglutination test (LAT) for the etiological diagnosis of pleural effusions caused by Streptococcus pneumoniae and Haemophilus influenzae type b. After thoracocentesis, paired fresh samples of pleural fluid from 418 children and adolescents were included in this investigation. They were tested blindly and simultaneously through counterimmunoelectrophoresis (CIE) and LAT for both bacteria. Sensitivity, specificity, predictive values and likelihood ratios (LR) were calculated taking CIE as a reference standard. The sensitivity and specificity of LAT was 100% (95% confidence interval, 94.4%-100%) and 83.3% (95% confidence interval, 79.0%-87.0%), respectively, whereas the positive (calculated from Bayes' theorem) and negative predictive values were, respectively, lower than 1% and 100% (95% confidence interval, 98.8%-100%). Positive and negative LR were 6.0 (95% confidence interval, 4.7-7.6) and zero, respectively. Our results suggest that LAT is a useful tool for the etiological diagnosis of pleural effusion. It is a reliable, rapid, simple to perform and shows an excellent yield in our studied population, helping to prescribe appropriate antibiotics for this clinical condition. © 2015 John Wiley & Sons Ltd.

Emerging Bacterial Infection: Identification and Clinical Significance of Kocuria Species

PubMed Central

Palange, Padmavali; Vaish, Ritu; Bhatti, Adnan Bashir; Kale, Vinod; Kandi, Maheshwar Reddy; Bhoomagiri, Mohan Rao

2016-01-01

Recently there have been reports of gram-positive cocci which are morphologically similar to both Staphylococci and the Micrococci. These bacteria have been identified as Kocuria species with the help of automated identification system and other molecular methods including 16S rRNA (ribosomal ribonucleic acid) evaluation. Kocuria belongs to the family Micrococcaceae which also includes Staphylococcus species and Micrococcus species. Isolation and clinical significance of these bacteria from human specimens warrant great caution as it does not necessarily confirm infection due to their ubiquitous presence, and as a normal flora of skin and mucous membranes in human and animals. Most clinical microbiology laboratories ignore such bacteria as laboratory and specimen contaminants. With increasing reports of infections associated with these bacteria, it is now important for clinical microbiologists to identify and enumerate the virulence and antibiotic susceptibility patterns of such bacteria and assist clinicians in improving the patient care and management. We review the occurrence and clinical significance of Kocuria species. PMID:27630804

A Rapid and Quantitative Flow Cytometry Method for the Analysis of Membrane Disruptive Antimicrobial Activity.

PubMed

O'Brien-Simpson, Neil M; Pantarat, Namfon; Attard, Troy J; Walsh, Katrina A; Reynolds, Eric C

2016-01-01

We describe a microbial flow cytometry method that quantifies within 3 hours antimicrobial peptide (AMP) activity, termed Minimum Membrane Disruptive Concentration (MDC). Increasing peptide concentration positively correlates with the extent of bacterial membrane disruption and the calculated MDC is equivalent to its MBC. The activity of AMPs representing three different membranolytic modes of action could be determined for a range of Gram positive and negative bacteria, including the ESKAPE pathogens, E. coli and MRSA. By using the MDC50 concentration of the parent AMP, the method provides high-throughput, quantitative screening of AMP analogues. A unique feature of the MDC assay is that it directly measures peptide/bacteria interactions and lysed cell numbers rather than bacteria survival as with MIC and MBC assays. With the threat of multi-drug resistant bacteria, this high-throughput MDC assay has the potential to aid in the development of novel antimicrobials that target bacteria with improved efficacy.

Exercise training in adults with repaired tetralogy of Fallot: A randomized controlled pilot study of continuous versus interval training.

PubMed

Novaković, Marko; Prokšelj, Katja; Rajkovič, Uroš; Vižintin Cuderman, Tjaša; Janša Trontelj, Katja; Fras, Zlatko; Jug, Borut

2018-03-15

Adults with repaired tetralogy of Fallot (ToF) have impaired exercise capacity, vascular and cardiac autonomic function, and quality of life (QoL). Specific effects of high-intensity interval or moderate continuous exercise training on these parameters in adults with repaired ToF remain unknown. Thirty adults with repaired ToF were randomized to either high-intensity interval, moderate intensity continuous training (36 sessions, 2-3 times a week) or usual care (no supervised exercise). Exercise capacity, flow-mediated vasodilation, pulse wave velocity, NT-proBNP and fibrinogen levels, heart rate variability and recovery, and QoL (SF-36 questionnaire) were determined at baseline and after the intervention period. Twenty-seven patients (mean age 39±9years, 63% females, 9 from each group) completed this pilot study. Both training groups improved in at least some parameters of cardiovascular health compared to no exercise. Interval-but not continuous-training improved VO2peak (21.2 to 22.9ml/kg/min, p=0.004), flow-mediated vasodilation (8.4 to 12.9%, p=0.019), pulse wave velocity (5.4 to 4.8m/s, p=0.028), NT-proBNP (202 to 190ng/L, p=0.032) and fibrinogen levels (2.67 to 2.46g/L, p=0.018). Conversely, continuous-but not interval-training improved heart rate variability (low-frequency domain, 0.32 to 0.22, p=0.039), heart rate recovery after 2min post-exercise (40 to 47 beats, p=0.023) and mental domain of SF-36 (87 to 95, p=0.028). Both interval and continuous exercise training modalities were safe. Interval training seems more efficacious in improving exercise capacity, vascular function, NT-proBNP and fibrinogen levels, while continuous training seems more efficacious in improving cardiac autonomic function and QoL. (Clinicaltrials.gov, NCT02643810). Copyright © 2018 Elsevier Ireland Ltd. All rights reserved.

Resistance-based interval exercise acutely improves endothelial function in type 2 diabetes.

PubMed

Francois, Monique E; Durrer, Cody; Pistawka, Kevin J; Halperin, Frank A; Little, Jonathan P

2016-11-01

Different modes of exercise, disease, and training status can modify endothelial shear stress and result in distinct effects on endothelial function. To date, no study has examined the influence of type 2 diabetes (T2D) and training status on the acute endothelial response to different modes of interval exercise (INT). We examined the effect of a single session of resistance- and cardio-based INT compared with a time-matched control on endothelial function in 12 age-matched T2D participants, 12 untrained, and 11 trained adults (aged 56 ± 7 yr). Flow-mediated dilation (%FMD) of the brachial artery was assessed at baseline and immediately, 1, and 2 h after an acute bout of cardio interval (C-INT), resistance interval (R-INT), and seated control (CTL); these interventions were randomized and separated by >2 days. C-INT involved seven 1-min cycling intervals at 85% of peak power with 1-min recovery between. R-INT involved the same pattern of seven 1-min intervals using leg resistance exercises. Endothelial function (%FMD) was improved after R-INT in all groups (Condition × Time interaction, P < 0.01), an effect that was most robust in T2D where %FMD was higher immediately (+4.0 ± 2.8%), 1 h (+2.5 ± 2.5%), and 2 h (+1.9 ± 1.9%) after R-INT compared with CTL (P < 0.01 for all). C-INT improved %FMD in T2D at 1-h postexercise (+1.6 ± 2.2%, P = 0.03) compared with CTL. In conclusion, R-INT acutely improves endothelial function throughout the 2-h postexercise period in T2D patients. The long-term impact of resistance exercise performed in an interval pattern is warranted. Copyright © 2016 the American Physiological Society.

Resistance-based interval exercise acutely improves endothelial function in type 2 diabetes

PubMed Central

Francois, Monique E.; Durrer, Cody; Pistawka, Kevin J.; Halperin, Frank A.

2016-01-01

Different modes of exercise, disease, and training status can modify endothelial shear stress and result in distinct effects on endothelial function. To date, no study has examined the influence of type 2 diabetes (T2D) and training status on the acute endothelial response to different modes of interval exercise (INT). We examined the effect of a single session of resistance- and cardio-based INT compared with a time-matched control on endothelial function in 12 age-matched T2D participants, 12 untrained, and 11 trained adults (aged 56 ± 7 yr). Flow-mediated dilation (%FMD) of the brachial artery was assessed at baseline and immediately, 1, and 2 h after an acute bout of cardio interval (C-INT), resistance interval (R-INT), and seated control (CTL); these interventions were randomized and separated by >2 days. C-INT involved seven 1-min cycling intervals at 85% of peak power with 1-min recovery between. R-INT involved the same pattern of seven 1-min intervals using leg resistance exercises. Endothelial function (%FMD) was improved after R-INT in all groups (Condition × Time interaction, P < 0.01), an effect that was most robust in T2D where %FMD was higher immediately (+4.0 ± 2.8%), 1 h (+2.5 ± 2.5%), and 2 h (+1.9 ± 1.9%) after R-INT compared with CTL (P < 0.01 for all). C-INT improved %FMD in T2D at 1-h postexercise (+1.6 ± 2.2%, P = 0.03) compared with CTL. In conclusion, R-INT acutely improves endothelial function throughout the 2-h postexercise period in T2D patients. The long-term impact of resistance exercise performed in an interval pattern is warranted. PMID:27638878

Belowground Interactions Impact the Soil Bacterial Community, Soil Fertility, and Crop Yield in Maize/Peanut Intercropping Systems

PubMed Central

Li, Qisong; Chen, Jun; Wu, Linkun; Luo, Xiaomian; Li, Na; Arafat, Yasir; Lin, Sheng; Lin, Wenxiong

2018-01-01

Intercropping has been widely used to control disease and improve yield in agriculture. In this study, maize and peanut were used for non-separation intercropping (NS), semi-separation intercropping (SS) using a nylon net, and complete separation intercropping (CS) using a plastic sheet. In field experiments, two-year land equivalent ratios (LERs) showed yield advantages due to belowground interactions when using NS and SS patterns as compared to monoculture. In contrast, intercropping without belowground interactions (CS) showed a yield disadvantage. Meanwhile, in pot experiments, belowground interactions (found in NS and SS) improved levels of soil-available nutrients (nitrogen (N) and phosphorus (P)) and enzymes (urease and acid phosphomonoesterase) as compared to intercropping without belowground interactions (CS). Soil bacterial community assay showed that soil bacterial communities in the NS and SS crops clustered together and were considerably different from the CS crops. The diversity of bacterial communities was significantly improved in soils with NS and SS. The abundance of beneficial bacteria, which have the functions of P-solubilization, pathogen suppression, and N-cycling, was improved in maize and peanut soils due to belowground interactions through intercropping. Among these bacteria, numbers of Bacillus, Brevibacillus brevis, and Paenibacillus were mainly increased in the maize rhizosphere. Burkholderia, Pseudomonas, and Rhizobium were mainly increased in the peanut rhizosphere. In conclusion, using maize and peanut intercropping, belowground interactions increased the numbers of beneficial bacteria in the soil and improved the diversity of the bacterial community, which was conducive to improving soil nutrient (N and P) supply capacity and soil microecosystem stability. PMID:29470429

Stimulating effects of two plant growth-promoting bacteria, Enterobacter ludwigii Ez-185-17 and Raoultella terrigena Ez-555-6, on flax culture

NASA Astrophysics Data System (ADS)

Sarron, Elodie; Clément, Nathalie; Pawlicki-Jullian, Nathalie; Gaillard, Isabelle; Boitel-Conti, Michèle

2018-04-01

Two bacteria, Enterobacter ludwigii Ez-185-17 and Raoultella terrigena Ez-555-6, isolated from root nodules of Medicago lupulina from the Chernobyl exclusion zone, were identified in a previous study and shown not to disturb plant growth. The main goal of this work is to elucidate the relationships between these bacteria and flax, in particular whether they display activities such as plant growth promoting bacteria (PGPB) properties or modulation hairy root development. In order to better understand their role in plants, some known PGPB properties were determined in comparison with several control bacteria. The influence of these bacteria on Linum usitatissimum growth under hydroponic conditions was also investigated. Our study shows that both bacteria belong to PGPB since they were able to increase considerably the root surface area of flax, especially Raoultella terrigena Ez-555-6. Significant IAA production and phosphate solubilization of Enterobacter ludwigii Ez-185-17 were highlighted, which enabled these biochemical PGPB properties to be correlated with their effects on flax growth. However, Raoultella terrigena Ez-555-6 did not express high biochemical activities, suggesting that other PGPB abilities should be studied in order to establish the link with flax growth improvement.

Quality evaluation of probiotic capsule prepared from alginate, carrageenan and tofu waste flour based on bacterial activity and organoleptic test

NASA Astrophysics Data System (ADS)

Muhardina, V.; Ermaya, D.; Aisyah, Y.; Haryani, S.

2018-02-01

Probiotic capsule is an innovation in functional food sector. It is used to preserve the living cells of probiotic bacteria during processing and storage. In this research, the improvement of probiotic viability is studied by using two kinds of encapsulating biomaterials and different concentration of tofu waste flour. Extrusion is selected method for encapsulation process. The purpose of this study is to examine the quality of probiotic capsule by evaluating the lactic acid bacteria performance and its physical characteristic. The article provides the data of probiotic bacteria activity related to their living cells present in capsule, activity in fermentation media compare to uncapsulated bacteria, and panelists’ preferences of capsule’s physical properties. The data is analyzed statistically by using ANOVA. The result shows that variables in this study affect the number of bacteria, their metabolic activity in producing acid during fermentation, and physical appearance of the capsule. Combination of alginate and tofu waste flour allows the multiplication of bacteria to a high number, and forms elastic, yellow and cloudy capsule, while with carrageenan, it causes the growth of a few numbers of bacteria which affects to a moderate pH and produces elastic, creamy and transparent capsule.

Skin microbiome: genomics-based insights into the diversity and role of skin microbes

PubMed Central

Kong, Heidi H.

2011-01-01

Recent advances in DNA sequencing methodology have enabled studies of human skin microbes that circumvent difficulties in isolating and characterizing fastidious microbes. Sequence-based approaches have identified greater diversity of cutaneous bacteria than studies using traditional cultivation techniques. However, improved sequencing technologies and analytical methods are needed to study all skin microbes, including bacteria, archaea, fungi, viruses, and mites, and how they interact with each other and their human hosts. This review discusses current skin microbiome research, with a primary focus on bacteria, and the challenges facing investigators striving to understand how skin micro-organisms contribute to health and disease. PMID:21376666

Mg2+ improves biomass production from soybean wastewater using purple non-sulfur bacteria.

PubMed

Wu, Pan; Zhang, Guangming; Li, Jianzheng

2015-02-01

Soybean wastewater was used to generate biomass resource by use of purple non-sulfur bacteria (PNSB). This study investigated the enhancement of PNSB cell accumulation in wastewater by Mg2+ under the light-anaerobic condition. Results showed that with the optimal Mg2+ dosage of 10 mg/L, biomass production was improved by 70% to 3630 mg/L, and biomass yield also was improved by 60%. Chemical Oxygen Demand (COD) removal reached above 86% and hydraulic retention time was shortened from 96 to 72 hr. The mechanism analysis indicated that Mg2+ could promote the content of bacteriochlorophyll in photosynthesis because Mg2+ is the bacteriochlorophyll active center, and thus improved adenosine triphosphate (ATP) production. An increase of ATP production enhanced the conversion of organic matter in wastewater into PNSB cell materials (biomass yield) and COD removal, leading to more biomass production. With 10 mg/L Mg2+, bacteriochlorophyll content and ATP production were improved by 60% and 33% respectively. Copyright © 2014. Published by Elsevier B.V.

Improved methane production from sugarcane vinasse with filter cake in thermophilic UASB reactors, with predominance of Methanothermobacter and Methanosarcina archaea and Thermotogae bacteria.

PubMed

Barros, Valciney Gomes de; Duda, Rose Maria; Vantini, Juliana da Silva; Omori, Wellington Pine; Ferro, Maria Inês Tiraboschi; Oliveira, Roberto Alves de

2017-11-01

Biogas production from sugarcane vinasse has enormous economic, energy, and environmental management potential. However, methane production stability and biodigested vinasse quality remain key issues, requiring better nutrient and alkalinity availability, operational strategies, and knowledge of reactor microbiota. This study demonstrates increased methane production from vinasse through the use of sugarcane filter cake and improved effluent recirculation, with elevated organic loading rates (OLR) and good reactor stability. We used UASB reactors in a two-stage configuration, with OLRs up to 45gCODL -1 d -1 , and obtained methane production as high as 3LL -1 d -1 . Quantitative PCR indicated balanced amounts of bacteria and archaea in the sludge (10 9 -10 10 copiesg -1 VS), and of the predominant archaea orders, Methanobacteriales and Methanosarcinales (10 6 -10 8 copiesg -1 VS). 16S rDNA sequencing also indicated the thermophilic Thermotogae as the most abundant class of bacteria in the sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

Use of natural compounds to improve the microbial stability of Amaranth-based homemade fresh pasta.

PubMed

Del Nobile, M A; Di Benedetto, N; Suriano, N; Conte, A; Lamacchia, C; Corbo, M R; Sinigaglia, M

2009-04-01

A study on the use of natural antimicrobial compounds to improve the microbiological stability of refrigerated amaranth-based homemade fresh pasta is presented in this work. In particular, the antimicrobial activity of thymol, lemon extract, chitosan and grapefruit seed extract (GFSE) has been tested against mesophilic and psychrotrophic bacteria, total coliforms, Staphylococcus spp., yeasts and moulds. A sensory analysis on both fresh and cooked pasta was also run. Results suggest that chitosan and GFSE strongly increase the microbial acceptability limit of the investigated spoilage microorganisms, being the former the most effective. Thymol efficiently reduces the growth of mesophilic bacteria, psychrotrophic bacteria and Staphylococcus spp., whereas it does not affect, substantially, the growth cycle of total coliforms. Lemon extract is the less effective in preventing microbial growth. In fact, it is able to delay only total mesophilic and psychrotrophic bacterial evolution. From a sensorial point of view no significant differences were recorded between the control samples and all the types of loaded amaranth-based pasta.

Influence of diets to Wistar rats supplemented with soya, flaxseed and lupine products treated by lactofermentation to improve their gut health.

PubMed

Bartkiene, E; Juodeikiene, G; Vidmantiene, D; Zdunczyk, Z; Zdunczyk, P; Juskiewicz, J; Cizeikiene, D; Matusevicius, P

2013-09-01

The present study proposes the contribution of lactic acid bacteria and plants rich in bioactive substances and high-quality proteins as alternative products for human diets in improving the gut environment as potential against pathogenic bacteria. The effect of diets supplemented with soya, flaxseed and lupine flours fermented with a Pediococcus acidilactici KTU05-7 probiotic strain in the gastrointestinal tract (GIT) of Wistar rats were analyzed. In vivo experiments showed a positive effect of long time lactofermentation of plant material on the body weight of rats. Diets with fermented yellow lupine resulted in enhanced activities of α-glucosidase, β-galactosidases, as well as high levels of lactic acid bacteria, bifidobacteria and enterococci in the GIT were determined. Lactofermentation of analyzed plant products had a significantly lowering effect on Escherichia coli compared with the control group. The dominant flora of large intestines like Bifidobacterium and anaerobic cocci were found in high levels after diets with fermented lupine.

Improved fermentation performance in an expanded ectopic fermentation system inoculated with thermophilic bacteria.

PubMed

Guo, Hui; Zhu, Changxiong; Geng, Bing; Liu, Xue; Ye, Jing; Tian, Yunlong; Peng, Xiawei

2015-12-01

Previous research showed that ectopic fermentation system (EFS) inoculated with thermophilic bacteria is an excellent alternative for cow wastewater treatment. In this study, the effects of thermophilic bacterial consortium on the efficiency and quality of the fermentation process in EFS were evaluated by measuring physicochemical and environmental factors and the changes in organic matter composition. In parallel, the microbial communities correlated with fermentation performance were identified. Inoculation of EFS with thermophilic bacterial consortium led to higher temperatures, increased wastewater requirements for continuous fermentation, and improved quality of the litters in terms of physicochemical factors, security test, functional group analysis, and bacterial community composition. The relationship between the transformation of organic component and the dominant bacteria species indicated that environmental factors contributed to strain growth, which subsequently promoted the fermentation process. The results highlight the great potential of EFS model for wide application in cow wastewater treatment and re-utilization as bio-fertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of probiotic bacteria involved in fermented milk processing enriched with folic acid.

PubMed

Wu, Zhen; Wu, Jing; Cao, Pei; Jin, Yifeng; Pan, Daodong; Zeng, Xiaoqun; Guo, Yuxing

2017-06-01

Yogurt products fermented with probiotic bacteria are a consumer trend and a challenge for functional food development. So far, limited research has focused on the behavior of the various probiotic strains used in milk fermentation. In the present study, we characterized folic acid production and the sensory and textural characteristics of yogurt products fermented with probiotic bacteria. Yogurt fermented with Lactobacillus plantarum had improved nutrient content and sensory and textural characteristics, but the presence of L. plantarum significantly impaired the growth and survival of Lactobacillus delbrueckii ssp. bulgaricus during refrigerated storage. Overall, L. plantarum was a good candidate for probiotic yogurt fermentation; further studies are needed to understand the major metabolite path of lactic acid bacteria in complex fermentation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Improved apparatus for continuous culture of hydrogen-fixing bacteria

NASA Technical Reports Server (NTRS)

Foster, J. F.; Litchfield, J. H.

1970-01-01

Improved apparatus permits the continuous culture of Hydrogenomonas eutropha. System incorporates three essential subsystems - /1/ environmentally isolated culture vessel, /2/ analytical system with appropriate sensors and readout devices, /3/ control system with feedback responses to each analytical measurement.

Discospondylitis caused by Staphylococcus aureus in an African black-footed penguin (Spheniscus demersus).

PubMed

Field, Cara L; Beaufrère, Hugues; Wakamatsu, Nobuko; Rademacher, Nathalie; MacLean, Robert

2012-12-01

A 22-year-old female African black-footed penguin (Spheniscus demersus), housed indoors with other African and rockhopper penguins, was presented acutely with lethargy, ataxia, and hind limb weakness after a molt. The penguin would assume a hunched position and, when resting, sat on its hocks or lay on its keel. Physical and neurologic examination revealed hind limb paraparesis, proprioceptive deficits, and tiptoe walking. Results of a complete blood cell count and biochemical analysis revealed mild heterophilic leukocytosis, anemia, mild hypoalbuminemia, hypokalemia, and hyperuricemia. Results of whole-body radiographs and coelioscopy were unremarkable. Two computed tomographies of the spine at a 3-month interval revealed a lesion at the mobile thoracic vertebra proximal to the synsacrum with associated spinal cord compression. The penguin was treated with itraconazole, doxycycline, and meloxicam, and it initially improved with return to near normal gait and behavior. However, 5 months after the onset of clinical signs, the penguin was euthanatized after a relapse with worsening of the neurologic signs. Postmortem and histopathologic examination revealed focal granulomatous discospondylitis at the penultimate mobile thoracic vertebra, with intralesional bacteria from which Staphylococcus aureus was cultured.

Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

PubMed

Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

2013-02-01

This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner reduced environmental pathogens in sawdust bedding and teat ends without affecting teat end integrity. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Bacteria on Urine Microscopy Is Not Associated with Systemic Infection in Patients with Obstructing Urolithiasis.

PubMed

Cheung, Felix; Loeb, Charles A; Croglio, Michael P; Waltzer, Wayne C; Weissbart, Steven J

2017-09-01

Determining whether bacterial presence in urine microscopy represents infection is important as ureteral stent placement is indicated in patients with obstructing urolithiasis and infection. We aim to investigate whether the presence of bacteria on urine microscopy is associated with other markers of infection in patients with obstructing urolithiasis presenting to the emergency room. We performed a cross-sectional study of 199 patients with obstructing urolithiasis and divided patients into two groups according to the presence of bacteria on urine microscopy. The primary outcome was serum white blood cell count and secondary outcomes were objective fever, subjective fever, tachycardia, pyuria, and final urine culture. Univariate and multivariate analysis were used to assess whether the presence of bacteria on microscopy was associated with other markers of infection. The study included 72 patients in the bacteriuria group and 127 without bacteriuria. On univariate analysis, the presence of bacteria was not associated with leukocytosis, objective fever, or subjective fever, but it was associated with gender (p < 0.001), pyuria (p < 0.001), positive nitrites (p = 0.001), positive leukocyte esterase (p < 0.001), and squamous epithelial cells (p = 0.002). In a multilinear regression model including the presence of squamous cells, age, and sex, the presence of bacteriuria was not related to serum white blood cell count (coefficient -0.47; 95% confidence interval [CI] -1.1, 0.2; p = 0.17), heart rate (coefficient 0.85; 95% CI -2.5, 4.2; p = 0.62), presence of subjective or objective fever (odds ratio [OR] 1.5; 95% CI 0.8, 3.1; p = 0.18), or the presence of squamous epithelial cells (coefficient -4.4; 95% CI -10, 1.2; p = 0.12). However, the presence of bacteriuria was related to only the degree of pyuria (coefficient 16.4; 95% CI 9.6, 23.3; p < 0.001). Bacteria on urine microscopy is not associated with other markers of systemic infection and may largely represent a contaminant. Renal colic may be a risk factor for providing a contaminated urine specimen.

Anti-Quorum Sensing Activity of Substances Isolated from Wild Berry Associated Bacteria

PubMed Central

Abudoleh, Suha M.; Mahasneh, Adel M.

2017-01-01

Background: Quorum Sensing (QS) is a mechanism used by bacteria to determine their physiological activities and coordinate gene expression based on cell to cell signaling. Many bacterial physiological functions are under the regulation of quorum sensing such as virulence, luminescence, motility, sporulation and biofilm formation. The aim of the present study was to isolate and characterize Quorum Sensing Inhibitory (QSI) substances from epiphytic bacteria residing on wild berries surfaces. Methods: Fifty nine bacterial isolates out of 600 screened bacteria were successfully isolated. These bacteria were obtained from berry surfaces of different plants in the wild forests of Ajloun-Jordan. Screening for QSI activity using Chromobacterium violaceum ATCC 12472 monitor strain, resulted in isolating 6 isolates exhibiting QSI activity only, 11 isolates with QSI and antibacterial activity, and 42 isolates with antibacterial activity only. Three potential isolates S 130, S 153, and S 664, were gram positive rods and spore formers, catalase positive and oxidase negative. These were chosen for further testing and characterization. Results: Different solvent extraction of the QSI substances based on polarity indicated that the activity of S 130 was in the butanol extract, S 153 activity in both chloroform and butanol; and for S 664, the activity was detected in the hexane extract. The chloroform extract of S 153 and hexane extract of S 664 were proteinaceous in nature while QSI substances of the butanol extract of S 130 and S 153 were non-proteinaceous. All the tested QSI substances showed a marked thermal stability when subjected at several time intervals to 70°C, with the highest stability observed for the butanol extract of S 153. Assessing the QSI substances using violacein quantification assay revealed varying degrees of activity depending upon the extracting solvent, type of the producer bacteria and the concentration of the substances. Conclusion: This study highlighted the potential of untapped reservoirs in nature to be used as a source of unique metabolite that may be further developed for therapy. The potential QSI substances included in this study are just one aspect to be further analyzed for use as biopharmaceutical agents. PMID:28090277

Fuzzy interval Finite Element/Statistical Energy Analysis for mid-frequency analysis of built-up systems with mixed fuzzy and interval parameters

NASA Astrophysics Data System (ADS)

Yin, Hui; Yu, Dejie; Yin, Shengwen; Xia, Baizhan

2016-10-01

This paper introduces mixed fuzzy and interval parametric uncertainties into the FE components of the hybrid Finite Element/Statistical Energy Analysis (FE/SEA) model for mid-frequency analysis of built-up systems, thus an uncertain ensemble combining non-parametric with mixed fuzzy and interval parametric uncertainties comes into being. A fuzzy interval Finite Element/Statistical Energy Analysis (FIFE/SEA) framework is proposed to obtain the uncertain responses of built-up systems, which are described as intervals with fuzzy bounds, termed as fuzzy-bounded intervals (FBIs) in this paper. Based on the level-cut technique, a first-order fuzzy interval perturbation FE/SEA (FFIPFE/SEA) and a second-order fuzzy interval perturbation FE/SEA method (SFIPFE/SEA) are developed to handle the mixed parametric uncertainties efficiently. FFIPFE/SEA approximates the response functions by the first-order Taylor series, while SFIPFE/SEA improves the accuracy by considering the second-order items of Taylor series, in which all the mixed second-order items are neglected. To further improve the accuracy, a Chebyshev fuzzy interval method (CFIM) is proposed, in which the Chebyshev polynomials is used to approximate the response functions. The FBIs are eventually reconstructed by assembling the extrema solutions at all cut levels. Numerical results on two built-up systems verify the effectiveness of the proposed methods.

Chitin Lengthens Power Production in a Sedimentary Microbial Fuel Cell

DTIC Science & Technology

2014-01-01

sulfate-reducing bacteria; marine I. INTRODUCTION Ocean-based energy recovery devices are often based on kinetic or solar energy harvesting . In...enhancement would scale with an increase in system size. More work is also planned on improving energy harvesting efficiency and understanding the...utilization by marine bacteria. Degradation and catabolism of chitin oligosaccharides by Vibrio furnissii,” J Biol Chem, 1991. vol 266, pp. 24276-24286

Abnormal gut microbiota composition contributes to cognitive dysfunction in SAMP8 mice.

PubMed

Zhan, Gaofeng; Yang, Ning; Li, Shan; Huang, Niannian; Fang, Xi; Zhang, Jie; Zhu, Bin; Yang, Ling; Yang, Chun; Luo, Ailin

2018-06-10

Alzheimer's disease is characterized by cognitive dysfunction and aging is an important predisposing factor; however, the pathological and therapeutic mechanisms are not fully understood. Recently, the role of gut microbiota in Alzheimer's disease has received increasing attention. The cognitive function in senescence-accelerated mouse prone 8 (SAMP8) mice was significantly decreased and the Chao 1 and Shannon indices, principal coordinates analysis, and principal component analysis results were notably abnormal compared with that of those in senescence-accelerated mouse resistant 1 (SAMR1) mice. Moreover, 27 gut bacteria at six phylogenetic levels differed between SAMP8 and SAMR1 mice. In a separate study, we transplanted fecal bacteria from SAMP8 or SAMR1 mice into pseudo germ-free mice. Interestingly, the pseudo germ-free mice had significantly lower cognitive function prior to transplant. Pseudo germ-free mice that received fecal bacteria transplants from SAMR1 mice but not from SAMP8 mice showed improvements in behavior and in α-diversity and β-diversity indices. In total, 14 bacteria at six phylogenetic levels were significantly altered by the gut microbiota transplant. These results suggest that cognitive dysfunction in SAMP8 mice is associated with abnormal composition of the gut microbiota. Thus, improving abnormal gut microbiota may provide an alternative treatment for cognitive dysfunction and Alzheimer's disease.

Bovine Milk as a Source of Functional Oligosaccharides for Improving Human Health12

PubMed Central

Zivkovic, Angela M.; Barile, Daniela

2011-01-01

Human milk oligosaccharides are complex sugars that function as selective growth substrates for specific beneficial bacteria in the gastrointestinal system. Bovine milk is a potentially excellent source of commercially viable analogs of these unique molecules. However, bovine milk has a much lower concentration of these oligosaccharides than human milk, and the majority of the molecules are simpler in structure than those found in human milk. Specific structural characteristics of milk-derived oligosaccharides are crucial to their ability to selectively enrich beneficial bacteria while inhibiting or being less than ideal substrates for undesirable and pathogenic bacteria. Thus, if bovine milk products are to provide human milk–like benefits, it is important to identify specific dairy streams that can be processed commercially and cost-effectively and that can yield specific oligosaccharide compositions that will be beneficial as new food ingredients or supplements to improve human health. Whey streams have the potential to be commercially viable sources of complex oligosaccharides that have the structural resemblance and diversity of the bioactive oligosaccharides in human milk. With further refinements to dairy stream processing techniques and functional testing to identify streams that are particularly suitable for enriching beneficial intestinal bacteria, the future of oligosaccharides isolated from dairy streams as a food category with substantiated health claims is promising. PMID:22332060

Bovine milk as a source of functional oligosaccharides for improving human health.

PubMed

Zivkovic, Angela M; Barile, Daniela

2011-05-01

Human milk oligosaccharides are complex sugars that function as selective growth substrates for specific beneficial bacteria in the gastrointestinal system. Bovine milk is a potentially excellent source of commercially viable analogs of these unique molecules. However, bovine milk has a much lower concentration of these oligosaccharides than human milk, and the majority of the molecules are simpler in structure than those found in human milk. Specific structural characteristics of milk-derived oligosaccharides are crucial to their ability to selectively enrich beneficial bacteria while inhibiting or being less than ideal substrates for undesirable and pathogenic bacteria. Thus, if bovine milk products are to provide human milk-like benefits, it is important to identify specific dairy streams that can be processed commercially and cost-effectively and that can yield specific oligosaccharide compositions that will be beneficial as new food ingredients or supplements to improve human health. Whey streams have the potential to be commercially viable sources of complex oligosaccharides that have the structural resemblance and diversity of the bioactive oligosaccharides in human milk. With further refinements to dairy stream processing techniques and functional testing to identify streams that are particularly suitable for enriching beneficial intestinal bacteria, the future of oligosaccharides isolated from dairy streams as a food category with substantiated health claims is promising.

Novel antimicrobial peptide CPF-C1 analogs with superior stabilities and activities against multidrug-resistant bacteria.

PubMed

Xie, Junqiu; Zhao, Qian; Li, Sisi; Yan, Zhibin; Li, Jing; Li, Yao; Mou, Lingyun; Zhang, Bangzhi; Yang, Wenle; Miao, Xiaokang; Jiang, Xianxing; Wang, Rui

2017-11-01

As numerous clinical isolates are resistant to most conventional antibiotics, infections caused by multidrug-resistant bacteria are associated with a higher death rate. Antimicrobial peptides show great potential as new antibiotics. However, a major obstacle to the development of these peptides as useful drugs is their low stability. To overcome the problem of the natural antimicrobial peptide CPF-C1, we designed and synthesized a series of analogs. Our results indicated that by introducing lysine, which could increase the number of positive charges, and by introducing tryptophan, which could increase the hydrophobicity, we could improve the antimicrobial activity of the peptides against multidrug-resistant strains. The introduction of d-amino acids significantly improved stability. Certain analogs demonstrated antibiofilm activities. In mechanistic studies, the analogs eradicated bacteria not just by interrupting the bacterial membranes, but also by linking to DNA, which was not impacted by known mechanisms of resistance. In a mouse model, certain analogs were able to significantly reduce the bacterial load. Among the analogs, CPF-9 was notable due to its greater antimicrobial potency in vitro and in vivo and its superior stability, lower hemolytic activity, and higher antibiofilm activity. This analog is a potential antibiotic candidate for treating infections induced by multidrug-resistant bacteria. © 2017 John Wiley & Sons A/S.

In vitro bioactivity investigations of Ti-15Mo alloy after electrochemical surface modification.

PubMed

Kazek-Kęsik, Alicja; Kuna, Karolina; Dec, Weronika; Widziołek, Magdalena; Tylko, Grzegorz; Osyczka, Anna M; Simka, Wojciech

2016-07-01

Titanium and its aluminum and vanadium-free alloys have especially great potential for medical applications. Electrochemical surface modification improves their surface bioactivity and stimulates osseointegration process. In this work, the effect of plasma electrolytic oxidation of the β-type alloy Ti-15Mo surface on its bioactivity is presented. Bioactivity of the modified alloy was investigated by immersion in simulated body fluid (SBF). Biocompatibility of the modified alloys were tested using human bone marrow stromal cells (hBMSC) and wild intestinal strains (DV/A, DV/B, DV/I/1) of Desulfovibrio desulfuricans bacteria. The particles of apatite were formed on the anodized samples. Human BMSC cells adhered well on all the examined surfaces and expressed ALP, collagen, and produced mineralized matrix as determined after 10 and 21 days of culture. When the samples were inoculated with D. desulfuricans bacteria, only single bacteria were visible on selected samples. There were no obvious changes in surface morphology among samples. Colonization and bacterial biofilm formation was observed on as-ground sample. In conclusion, the surface modification improved the Ti-15Mo alloy bioactivity and biocompatibility and protected surface against colonization of the bacteria. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 903-913, 2016. © 2015 Wiley Periodicals, Inc.

Improved control of multiple-antibiotic-resistance-related microbial risk in swine manure wastes by autothermal thermophilic aerobic digestion.

PubMed

Han, Il; Congeevaram, Shankar; Park, Joonhong

2009-01-01

In this study, we microbiologically evaluated antibiotic resistance and pathogenicity in livestock (swine) manure as well as its biologically stabilized products. One of new livestock manure stabilization techniques is ATAD (Autothermal Thermophilic Aerobic Digestion). Because of its high operation temperature (60-65 degrees C), it has been speculated to have effective microbial risk control in livestock manure. This hypothesis was tested by evaluating microbial risk in ATAD-treated swine manure. Antibiotic resistance, multiple antibiotic resistance (MAR), and pathogenicity were microbiologically examined for swine manure as well as its conventionally stabilized (anaerobically fermented) and ATAD-stabilized products. In the swine manure and its conventionally stabilized product, antibiotic resistant (tetracycline-, kanamycine-, ampicillin-, and rifampicin-resistant) bacteria and the pathogen indicator bacteria were detected. Furthermore, approximately 2-5% of the Staphylococcus and Salmonella colonies from their selective culture media were found to exhibit a MAR-phenotypes, suggesting a serious level of microbe induced health risk. In contrast, after the swine manure was stabilized with a pilot-scale ATAD treatment for 3 days at 60-65 degrees C, antibiotic resistant bacteria, pathogen indicator bacteria, and MAR-exhibiting pathogens were all undetected. These findings support the improved control of microbial risk in livestock wastes by ATAD treatment.

Testing Proximate Cause Hypotheses for the End-Ordovician Mass Extinction: Do Patterns of Change in Biomarker Signatures Support a Linkage Between Graptolite and Phytoplankton Community Changes?

NASA Astrophysics Data System (ADS)

Marshall, N.; Thomas, E.; Mitchell, C. E.; Aga, D.; Wombacher, R.

2017-12-01

The goal of our study is to analyze the biomarkers in the Vinini Creek section based on a set of samples in which graptolite community change has been identified. The study will test several competing hypotheses about the cause of the observed changes in the environmental proxies and the graptolite community structure and composition. The study interval in the Late Ordovician (444.7-443.4 Ma) was a glacial period with varying climate and sea level changes that are marked by geochemical signatures. Climate change drove changes in deep-ocean circulation and upwelling zones during the concomitant mass extinction and it appears that the graptolites inhabiting the mesopelagic zone were the most vulnerable during these events. Due to the high vulnerability of the graptolites in the Vinini Creek section, biomarkers in the section are especially important for interpreting changing ocean conditions. Changing productivity in the upwelling zones of modern oceans is reflected in the microbial community, which forms the base of the food chain and drives biogeochemical cycles. Moreover, microbes can be traced using organism-specific biomarkers. Steranes (C27-C29) are biomarkers for eukaryotic organisms (e.g., green algae) and hopanes (C27-C35) are biomarkers for bacteria. We will determine hopane-sterane ratios, which reflect measurable relative contributions of bacteria and eukaryotes to sedimentary organic matter as a result of fluctuations in the strength of the oxygen minimum zone and associated denitrification processes. Previous work at lower resolution in this section suggests a decrease in denitrification and increase in abundance of eukaryotes (e.g., green algae) relative to bacteria within the Hirnantian glacial lowstand interval, roughly synchronously with the mass extinction. These relationships suggest that climatically driven changes in nutrient cycling and phytoplankton communities drove the mass extinction. If this is so, then changes in graptolite community structure and declines in mesopelagic species abundance will be associated in our data with a decreased hopane-sterane ratio and increased eukaryotic C29 biomarkers in step with the series of relative sea level changes recorded in these rocks.

Evaluation of the Solar Water Disinfection Method Using an Ultraviolet Measurement Device

NASA Astrophysics Data System (ADS)

Leung, H.

2015-12-01

Drinking water security is a growing problem for the population of planet Earth. According to WHO, more than 750 million people on our planet lack access to safe drinking water, resulting in approximately 502,000 diarrhoea deaths in 2012. In order to solve this problem, the Swiss water research institute, Eawag, has developed a method of solar water disinfection, called, "SODIS" The theory of SODIS is simple to understand: a clear plastic bottle filled with water is placed under full sunlight for at least 6 hours. The ultraviolet radiation kills the pathogens in the water, making the originally contaminated water safe for drinking. In order to improve this method, Helioz, an Austrian social enterprise, has created the WADI, a UV measurement device which determines when water is safe for drinking using the SODIS method. When using the WADI, the device should be placed under the sun and surrounded with bottles of water that need to be decontaminated. There is a UV sensor on the WADI, and since the bottles of water and the WADI will have equal exposure to sunlight, the WADI will be able to measure the impact of the sunlight on the contaminated water. This experiment tests the accuracy of the WADI device regarding the time interval needed for contaminated water to be disinfected. The experiment involves using the SODIS method to purify bottles of water contaminated with controlled samples of E. coli. Samples of the water are taken at different time intervals, and the E. coli levels are determined by growing the bacteria from the water samples on agar plates. Ultimately, this helps determine when the water is safe for drinking, and are compared against the WADI's measurements to test the reliability of the device.

Identification and Characterization of Potential Performance-Related Gut Microbiotas in Broiler Chickens across Various Feeding Trials▿†

PubMed Central

Torok, Valeria A.; Hughes, Robert J.; Mikkelsen, Lene L.; Perez-Maldonado, Rider; Balding, Katherine; MacAlpine, Ron; Percy, Nigel J.; Ophel-Keller, Kathy

2011-01-01

Three broiler feeding trials were investigated in order to identify gut bacteria consistently linked with improvements in bird performance as measured by feed efficiency. Trials were done in various geographic locations and varied in diet composition, broiler breed, and bird age. Gut microbial communities were investigated using microbial profiling. Eight common performance-linked operational taxonomic units (OTUs) were identified within both the ilea (180, 492, and 564–566) and ceca (140–142, 218–220, 284–286, 312, and 482) across trials. OTU 564–566 was associated with lower performance, while OTUs 140–142, 482, and 492 were associated with improved performance. Targeted cloning and sequencing of these eight OTUs revealed that they represented 26 bacterial species or phylotypes which clustered phylogenetically into seven groups related to Lactobacillus spp., Ruminococcaceae, Clostridiales, Gammaproteobacteria, Bacteroidales, Clostridiales/Lachnospiraceae, and unclassified bacteria/clostridia. Where bacteria were identifiable to the phylum level, they belonged predominantly to the Firmicutes, with Bacteroidetes and Proteobacteria also identified. Some of the potential performance-related phylotypes showed high sequence identity with classified bacteria (Lactobacillus salivarius, Lactobacillus aviarius, Lactobacillus crispatus, Faecalibacterium prausnitzii, Escherichia coli, Gallibacterium anatis, Clostridium lactatifermentans, Ruminococcus torques, Bacteroides vulgatus, and Alistipes finegoldii). The 16S rRNA gene sequence information generated will allow quantitative assays to be developed which will enable elucidations of which of these phylotypes are truly performance related. This information could be used to monitor strategies to improve feed efficiency and feed formulation for optimal gut health. PMID:21742925

Lactic Acid Bacteria Improves Peyer's Patch Cell-Mediated Immunoglobulin A and Tight-Junction Expression in a Destructed Gut Microbial Environment.

PubMed

Kim, Sung Hwan; Jeung, Woonhee; Choi, Il-Dong; Jeong, Ji-Woong; Lee, Dong Eun; Huh, Chul-Sung; Kim, Geun-Bae; Hong, Seong Soo; Shim, Jae-Jung; Lee, Jung Lyoul; Sim, Jae-Hun; Ahn, Young-Tae

2016-06-28

To evaluate the effects of lactic acid bacteria (LAB) on Peyer's patch cells, mice were treated with a high dose of kanamycin to disturb the gut microbial environment. The overarching goal was to explore the potential of LAB for use as a dietary probiotic that buffers the negative consequences of antibiotic treatment. In vitro, LAB stimulated the production of immunoglobulin A (IgA) from isolated Peyer's patch cells. Inflammation-related genes (TNF-α, IL-1β, and IL-8) were up-regulated in Caco-2 cells stimulated with lipopolysaccharide (LPS), while tight-junction-related genes (ZO-1 and occludin) were down-regulated; the effects of LPS on inflammatory gene and tight-junction gene expression were reversed by treatment with LAB. Mice treated with a high dose of kanamycin showed increased serum IgE levels and decreases in serum IgA and fecal IgA levels; the number of Peyer's patch cells decreased with kanamycin treatment. However, subsequent LAB treatment was effective in reducing the serum IgE level and recovering the serum IgA and fecal IgA levels, as well as the number of Peyer's patch cells. In addition, ZO-1 and occludin mRNA levels were up-regulated in the ileum tissues of mice receiving LAB treatment. Lactic acid bacteria can enhance the intestinal immune system by improving the integrity of the intestinal barrier and increasing the production of IgA in Peyer's patches. Lactic acid bacteria should be considered a potential probiotic candidate for improving intestinal immunity, particularly in mitigating the negative consequences of antibiotic use.

An Alternative Approach to "Identification of Unknowns": Designing a Protocol to Verify the Identities of Nitrogen Fixing Bacteria.

PubMed

Martinez-Vaz, Betsy M; Denny, Roxanne; Young, Nevin D; Sadowsky, Michael J

2015-12-01

Microbiology courses often include a laboratory activity on the identification of unknown microbes. This activity consists of providing students with microbial cultures and running biochemical assays to identify the organisms. This approach lacks molecular techniques such as sequencing of genes encoding 16S rRNA, which is currently the method of choice for identification of unknown bacteria. A laboratory activity was developed to teach students how to identify microorganisms using 16S rRNA polymerase chain reaction (PCR) and validate microbial identities using biochemical techniques. We hypothesized that designing an experimental protocol to confirm the identity of a bacterium would improve students' knowledge of microbial identification techniques and the physiological characteristics of bacterial species. Nitrogen-fixing bacteria were isolated from the root nodules of Medicago truncatula and prepared for 16S rRNA PCR analysis. Once DNA sequencing revealed the identity of the organisms, the students designed experimental protocols to verify the identity of rhizobia. An assessment was conducted by analyzing pre- and posttest scores and by grading students' verification protocols and presentations. Posttest scores were higher than pretest scores at or below p = 0.001. Normalized learning gains (G) showed an improvement of students' knowledge of microbial identification methods (LO4, G = 0.46), biochemical properties of nitrogen-fixing bacteria (LO3, G = 0.45), and the events leading to the establishment of nitrogen-fixing symbioses (LO1&2, G = 0.51, G = 0.37). An evaluation of verification protocols also showed significant improvement with a p value of less than 0.001.

Enhanced performance of the microalga Chlorella sorokiniana remotely induced by the plant growth-promoting bacteria Azospirillum brasilense and Bacillus pumilus

PubMed Central

Amavizca, Edgar; Bashan, Yoav; Ryu, Choong-Min; Farag, Mohamed A.; Bebout, Brad M.; de-Bashan, Luz E.

2017-01-01

Remote effects (occurring without physical contact) of two plant growth-promoting bacteria (PGPB) Azospirillum brasilense Cd and Bacilus pumilus ES4 on growth of the green microalga Chlorella sorokiniana UTEX 2714 were studied. The two PGPB remotely enhanced the growth of the microalga, up to six-fold, and its cell volume by about three-fold. In addition to phenotypic changes, both bacteria remotely induced increases in the amounts of total lipids, total carbohydrates, and chlorophyll a in the cells of the microalga, indicating an alteration of the microalga’s physiology. The two bacteria produced large amounts of volatile compounds, including CO2, and the known plant growth-promoting volatile 2,3-butanediol and acetoin. Several other volatiles having biological functions in other organisms, as well as numerous volatile compounds with undefined biological roles, were detected. Together, these bacteria-derived volatiles can positively affect growth and metabolic parameters in green microalgae without physical attachment of the bacteria to the microalgae. This is a new paradigm on how PGPB promote growth of microalgae which may serve to improve performance of Chlorella spp. for biotechnological applications. PMID:28145473

The Application Of Microbial Enhanced Oil Recovery On Unconventional Oil: A Field Specific Approach

NASA Astrophysics Data System (ADS)

Goodman, Sean; Millar, Andrew; Allison, Heather; McCarthy, Alan

2014-05-01

A substantial amount of the world's recoverable oil reserves are made from unconventional or heavy resources. However, great difficulty has been had in recovering this oil after primary and secondary recovery methods have been employed. Therefore, tertiary methods such as microbial enhanced oil recovery (MEOR) have been employed. MEOR involves the use of bacteria and their metabolic products to alter the oil properties or rock permeability within a reservoir in order to promote the flow of oil. Although MEOR has been trialed in the past with mixed outcomes, its feasibility on heavier oils has not been demonstrated. The aim of this study is to show that MEOR can be successfully applied to unconventional oils. By using an indigenous strain of bacteria isolated from a reservoir of interest and applied to field specific microcosms, we will look into the effect of these bacteria compared to variant inoculums to identify which mechanisms of action the bacteria are using to improve recovery. Using this information, we will be able to identify genes of interest and groups of bacteria that may be beneficial for MEOR and look accurately identify favorable bacteria within a reservoir.

Multidrug-resistant bacteria infection and nursing quality management application in the department of physical examination.

PubMed

Xu, Li; Luo, Qiang; Chen, Liangzhen; Jiao, Lingmei

2017-09-01

The main problem of clinical prevention and control of multi drug resistant bacteria infection is to strengthen the monitoring of pathogenic bacteria spectrum, this study research on the multi drug-resistant bacteria infection and nursing quality management application in the department of physical examination. The results of this study showed that the number of patients with multiple drug resistant infections showed an increasing trend. Therefore, once the patients with multiple drug-resistant bacteria infection are found, the prevention and control of the patients with multiple drug-resistant bacteria should be strictly followed, and the patient's medication care should be highly valued. Also, the nurses need to be classified based on the knowledge and skill characteristics of the nurses in the department of physical examination, and compare the nursing effect before and after classification and grouping. The physicians and individuals receiving physical examinations in the department of physical examination had a higher degree of satisfaction for nursing effect after classification compared with those before classification. Classification and grouping management helps improve the nursing quality and overall quality of the nurses in the department of physical examination.

Effects of microencapsulated Lactobacillus plantarum LIP-1 on the gut microbiota of hyperlipidaemic rats.

PubMed

Song, Jiao J; Tian, Wen J; Kwok, Lai-Yu; Wang, Ya L; Shang, Yi N; Menghe, Bilige; Wang, Jun G

2017-10-01

The in vivo effects of administering free and microencapsulated Lactobacillus plantarum LIP-1 cells (2·0×109 colony-forming units/d) were evaluated in high-fat-diet-induced hyperlipidaemic rats. Results from real-time quantitative PCR targeting to LIP-1 cells showed a higher colon colonisation count of LIP-1 in the rats receiving microencapsulated cells compared with free cells (P<0·05). Moreover, the microencapsulated LIP-1 treatment resulted in a more obvious lipid-lowering effect (P<0·05). Meanwhile, their faecal samples had significantly less lipopolysaccharide-producing bacteria (especially Bilophila, Sutterella and Oscillibacter) and mucosa-damaging bacteria (Bilophila and Akkermansia muciniphila), whereas significantly more SCFA-producing bacteria (P<0·05) (namely Lactobacillus, Alloprevotella, Coprococcus, Eubacterium and Ruminococcus) and bacteria that potentially possessed bile salt hydrolase activity (Bacteroides, Clostridium, Eubacterium and Lactobacillus), and other beneficial bacteria (Alistipes and Turicibacter). Further, Spearman's correlation analysis showed significant correlations between some of the modulated gut bacteria and the serum lipid levels. These results together confirm that microcapsulation enhanced the colon colonisation of LIP-1 cells, which subsequently exhibited more pronounced effects in improving the gut microbiota composition of hyperlipidaemic rats and lipid reduction.

Using Screencast Videos to Enhance Undergraduate Students' Statistical Reasoning about Confidence Intervals

ERIC Educational Resources Information Center

Strazzeri, Kenneth Charles

2013-01-01

The purposes of this study were to investigate (a) undergraduate students' reasoning about the concepts of confidence intervals (b) undergraduate students' interactions with "well-designed" screencast videos on sampling distributions and confidence intervals, and (c) how screencast videos improve undergraduate students' reasoning ability…

Optimization of the Reconstruction Interval in Neurovascular 4D-CTA Imaging

PubMed Central

Hoogenboom, T.C.H.; van Beurden, R.M.J.; van Teylingen, B.; Schenk, B.; Willems, P.W.A.

2012-01-01

Summary Time resolved whole brain CT angiography (4D-CTA) is a novel imaging technology providing information regarding blood flow. One of the factors that influence the diagnostic value of this examination is the temporal resolution, which is affected by the gantry rotation speed during acquisition and the reconstruction interval during post-processing. Post-processing determines the time spacing between two reconstructed volumes and, unlike rotation speed, does not affect radiation burden. The data sets of six patients who underwent a cranial 4D-CTA were used for this study. Raw data was acquired using a 320-slice scanner with a rotation speed of 2 Hz. The arterial to venous passage of an intravenous contrast bolus was captured during a 15 s continuous scan. The raw data was reconstructed using four different reconstruction-intervals: 0.2, 0.3, 0.5 and 1.0 s. The results were rated by two observers using a standardized score sheet. The appearance of each lesion was rated correctly in all readings. Scoring for quality of temporal resolution revealed a stepwise improvement from the 1.0 s interval to the 0.3 s interval, while no discernable improvement was noted between the 0.3 s and 0.2 s interval. An increase in temporal resolution may improve the diagnostic quality of cranial 4D-CTA. Using a rotation speed of 0.5 s, the optimal reconstruction interval appears to be 0.3 s, beyond which, changes can no longer be discerned. PMID:23217631

Effects of High Intensity Interval Training and Strength Training on Metabolic, Cardiovascular and Hormonal Outcomes in Women with Polycystic Ovary Syndrome: A Pilot Study.

PubMed

Almenning, Ida; Rieber-Mohn, Astrid; Lundgren, Kari Margrethe; Shetelig Løvvik, Tone; Garnæs, Kirsti Krohn; Moholdt, Trine

2015-01-01

Polycystic ovary syndrome is a common endocrinopathy in reproductive-age women, and associates with insulin resistance. Exercise is advocated in this disorder, but little knowledge exists on the optimal exercise regimes. We assessed the effects of high intensity interval training and strength training on metabolic, cardiovascular, and hormonal outcomes in women with polycystic ovary syndrome. Three-arm parallel randomized controlled trial. Thirty-one women with polycystic ovary syndrome (age 27.2 ± 5.5 years; body mass index 26.7 ± 6.0 kg/m2) were randomly assigned to high intensity interval training, strength training, or a control group. The exercise groups exercised three times weekly for 10 weeks. The main outcome measure was change in homeostatic assessment of insulin resistance (HOMA-IR). HOMA-IR improved significantly only after high intensity interval training, by -0.83 (95% confidence interval [CI], -1.45, -0.20), equal to 17%, with between-group difference (p = 0.014). After high intensity interval training, high-density lipoprotein cholesterol increased by 0.2 (95% CI, 0.02, 0.5) mmol/L, with between group difference (p = 0.04). Endothelial function, measured as flow-mediated dilatation of the brachial artery, increased significantly after high intensity interval training, by 2.0 (95% CI, 0.1, 4.0) %, between-group difference (p = 0.08). Fat percentage decreased significantly after both exercise regimes, without changes in body weight. After strength training, anti-Müllarian hormone was significantly reduced, by -14.8 (95% CI, -21.2, -8.4) pmol/L, between-group difference (p = 0.04). There were no significant changes in high-sensitivity C-reactive protein, adiponectin or leptin in any group. High intensity interval training for ten weeks improved insulin resistance, without weight loss, in women with polycystic ovary syndrome. Body composition improved significantly after both strength training and high intensity interval training. This pilot study indicates that exercise training can improve the cardiometabolic profile in polycystic ovary syndrome in the absence of weight loss. ClinicalTrial.gov NCT01919281.

Fourier-transform infrared derivative spectroscopy with an improved signal-to-noise ratio.

PubMed

Fetterman, M R

2005-09-01

Infrared derivative spectroscopy is a useful technique for finding peaks hidden in broad spectral features. A data acquisition technique is shown that will improve the signal-to-noise ratio (SNR) of Fourier-transform infrared (FTIR) derivative spectroscopy. Typically, in a FTIR measurement one samples each point for the same time interval. The effect of using a graded time interval is studied. The simulations presented show that the SNR of first-derivative FTIR spectroscopy will improve by 15% and that the SNR of second-derivative FTIR will improve by 34%.

Encapsulation of probiotic bacteria with alginate-starch and evaluation of survival in simulated gastrointestinal conditions and in yoghurt.

PubMed

Sultana, K; Godward, G; Reynolds, N; Arumugaswamy, R; Peiris, P; Kailasapathy, K

2000-12-05

A modified method using calcium alginate for the microencapsulation of probiotic bacteria is reported in this study. Incorporation of Hi-Maize starch (a prebiotic) improved encapsulation of viable bacteria as compared to when the bacteria were encapsulated without the starch. Inclusion of glycerol (a cryo-protectant) with alginate mix increased the survival of bacteria when frozen at -20 degrees C. The acidification kinetics of encapsulated bacteria showed that the rate of acid produced was lower than that of free cultures. The encapsulated bacteria, however, did not demonstrate a significant increase in survival when subjected to in vitro high acid and bile salt conditions. A preliminary study was carried out in order to monitor the effects of encapsulation on the survival of Lactobacillus acidophilus and Bifidobacterium spp. in yoghurt over a period of 8 weeks. This study showed that the survival of encapsulated cultures of L. acidophilus and Bifidobacterium spp. showed a decline in viable count of about 0.5 log over a period of 8 weeks while there was a decline of about 1 log in cultures which were incorporated as free cells in yoghurt. The encapsulation method used in this study did not result in uniform bead size, and hence additional experiments need to be designed using uniform bead size in order to assess the role of different encapsulation parameters, such as bead size and alginate concentration, in providing protection to the bacteria.

Lactic acid bacteria: promising supplements for enhancing the biological activities of kombucha.

PubMed

Nguyen, Nguyen Khoi; Dong, Ngan Thi Ngoc; Nguyen, Huong Thuy; Le, Phu Hong

2015-01-01

Kombucha is sweetened black tea that is fermented by a symbiosis of bacteria and yeast embedded within a cellulose membrane. It is considered a health drink in many countries because it is a rich source of vitamins and may have other health benefits. It has previously been reported that adding lactic acid bacteria (Lactobacillus) strains to kombucha can enhance its biological functions, but in that study only lactic acid bacteria isolated from kefir grains were tested. There are many other natural sources of lactic acid bacteria. In this study, we examined the effects of lactic acid bacteria from various fermented Vietnamese food sources (pickled cabbage, kefir and kombucha) on kombucha's three main biological functions: glucuronic acid production, antibacterial activity and antioxidant ability. Glucuronic acid production was determined by high-performance liquid chromatography-mass spectrometry, antibacterial activity was assessed by the agar-well diffusion method and antioxidant ability was evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. Four strains of food-borne pathogenic bacteria were used in our antibacterial experiments: Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778. Our findings showed that lactic acid bacteria strains isolated from kefir are superior to those from other sources for improving glucuronic acid production and enhancing the antibacterial and antioxidant activities of kombucha. This study illustrates the potential of Lactobacillus casei and Lactobacillus plantarum isolated from kefir as biosupplements for enhancing the bioactivities of kombucha.

Effects of poly-γ-glutamic acid biopreparation (PGAB) on nitrogen conservation in the coastal saline soil

NASA Astrophysics Data System (ADS)

Chen, Lihua; Xu, Xianghong; Zhang, Huan; Han, Rui; Cheng, Yao; Tan, Xueyi; Chen, Xuanyu

2017-04-01

Water leaching is the major method to decrease soil salinity of the coastal saline soil. Conservation of soil nutrition in the soil ameliorating process is helpful to maintain soil fertility and prevent environment pollution. In the experiment, glutamic acid and poly-γ-glutamic acid (PGA) producing bacteria were isolated for manufacturing the PGA biopreparation (PGAB), and the effect of PGAB on the soil nitrogen (N) conservation was assayed. The glutamic acid and PGA producing bacteria were identified as Brevibacterium flavum and Bacillus amyloliquefaciens. After soil leached with water for 90 days, compared to control treatment, salt concentration of 0-30cm soil with PGAB treatment was lowered by 39.93%, however the total N loss was decreased by 65.37%. Compared to control, the microbial biomass N increased by 1.19 times at 0-30 cm soil with PGAB treatment. The populations of soil total bacteria, fungi, actinomyces, nitrogen fixing bacteria, ammonifying bacteria, nitrifying bacteria and denitrifying bacteria and biomass of soil algae were significantly increased in PGAB treatment, while anaerobic bacteria decreased (P<0.05). In addition, the percentage of soil aggregates with diameter > 0.25 mm and 0.02 mm < diameter <0.25 mm were increased by 2.93 times and 26.79% respectively in PGAB treatment. The soil erosion-resistance coefficient of PGAB treatment increased by 50%. All these suggested that the PGAB conserved the soil nitrogen effectively in the process of soil water leaching and improved the coastal saline soil quality.

A microsensor for the detection of a single pathogenic bacterium using magnetotactic bacteria-based bio-carriers: simulations and preliminary experiments.

PubMed

Denomme, Ryan C; Lu, Zhao; Martel, Sylvain

2007-01-01

The proposed Magnetotactic Bacteria (MTB) based bio-carrier has the potential to greatly improve pathogenic bacteria detection time, specificity, and sensitivity. Microbeads are attached to the MTB and are modified with a coating of an antibody or phage that is specific to the target pathogenic bacteria. Using magnetic fields, the modified MTB are swept through a solution and the target bacteria present become attached to the microbeads (due to the coating). Then, the MTB are brought to the detection region and the number of pathogenic bacteria is determined. The high swimming speed and controllability of the MTB make this method ideal for the fast detection of small concentrations of specific bacteria. This paper focuses on an impedimetric detection system that will be used to identify if a target bacterium is attached to the microbead. The proposed detection system measures changes in electrical impedance as objects (MTB, microbeads, and pathogenic bacteria) pass through a set of microelectrodes embedded in a microfluidic device. FEM simulation is used to acquire the optimized parameters for the design of such a system. Specifically, factors such as electrode/detection channel geometry, object size and position, which have direct effects on the detection sensitivity for a single bacterium or microparticle, are investigated. Polymer microbeads and the MTB system with an E. coli bacterium are considered to investigate their impedance variations. Furthermore, preliminary experimental data using a microfabricated microfluidic device connected to an impedance analyzer are presented.

Impact of Periodic Presumptive Treatment for Bacterial Vaginosis on the Vaginal Microbiome among Women Participating in the Preventing Vaginal Infections Trial.

PubMed

Balkus, Jennifer E; Srinivasan, Sujatha; Anzala, Omu; Kimani, Joshua; Andac, Chloe; Schwebke, Jane; Fredricks, David N; McClelland, R Scott

2017-03-01

Evidence suggests that specific vaginal bacteria associated with bacterial vaginosis (BV) may increase the risk of adverse health outcomes in women. Among women participating in a randomized, double-blinded trial, we assessed the effect of periodic presumptive treatment (PPT) on detection of select vaginal bacteria. High-risk women from the United States and Kenya with a recent vaginal infection received intravaginal metronidazole 750 mg plus miconazole 200 mg or placebo for 5 consecutive nights each month for 12 months. Vaginal fluid specimens were collected via polyester/polyethylene terephthalate swabs every other month and tested for bacteria, using quantitative polymerase chain reaction (PCR) assays targeting the 16S ribosomal RNA gene. The effect of PPT on bacterium detection was assessed among all participants and stratified by country. Of 234 women enrolled, 221 had specimens available for analysis. The proportion of follow-up visits with detectable quantities was lower in the PPT arm versus the placebo arm for the following bacteria: BVAB1, BVAB2, Atopobium vaginae, Leptotrichia/Sneathia, and Megasphaera. The magnitude of reductions was greater among Kenyan participants as compared to US participants. Use of monthly PPT for 1 year reduced colonization with several bacteria strongly associated with BV. The role of PPT to improve vaginal health should be considered, and efforts to improve the impact of PPT regimens are warranted. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Microbial Community Transplant Results in Increased and Long-Term Oxalate Degradation

PubMed Central

Miller, Aaron W.; Oakeson, Kelly F.; Dale, Colin; Dearing, M. Denise

2016-01-01

Gut microbes are essential for the degradation of dietary oxalate, and this function may play a role in decreasing the incidence of kidney stones. However, many oxalate-degrading bacteria are susceptible to antibiotics and the use of oxalate-degrading probiotics has only led to an ephemeral reduction in urinary oxalate. The objective of the current study was to determine the efficacy of using whole-community microbial transplants from a wild mammalian herbivore, Neotoma albigula, to increase oxalate degradation over the long term in the laboratory rat, Rattus norvegicus. We quantified the change in total oxalate degradation in lab rats immediately after microbial transplants and at 2- and 9-month intervals following microbial transplants. Additionally, we tracked the fecal microbiota of the lab rats, with and without microbial transplants, using high-throughput Illumina sequencing of a hyper-variable region of the 16S rRNA gene. Microbial transplants resulted in a significant increase in oxalate degradation, an effect that persisted 9 months after the initial transplants. Functional persistence was corroborated by the transfer, and persistence of a group of bacteria previously correlated with oxalate consumption in N. albigula, including an anaerobic bacterium from the genus Oxalobacter known for its ability to use oxalate as a sole carbon source. The results of this study indicate that whole-community microbial transplants are an effective means for the persistent colonization of oxalate-degrading bacteria in the mammalian gut. PMID:27312892

Detection and identification of intestinal pathogenic bacteria by hybridization to oligonucleotide microarrays

PubMed Central

Jin, Lian-Qun; Li, Jun-Wen; Wang, Sheng-Qi; Chao, Fu-Huan; Wang, Xin-Wei; Yuan, Zheng-Quan

2005-01-01

AIM: To detect the common intestinal pathogenic bacteria quickly and accurately. METHODS: A rapid (<3 h) experimental procedure was set up based upon the gene chip technology. Target genes were amplified and hybridized by oligonucleotide microarrays. RESULTS: One hundred and seventy strains of bacteria in pure culture belonging to 11 genera were successfully discriminated under comparatively same conditions, and a series of specific hybridization maps corresponding to each kind of bacteria were obtained. When this method was applied to 26 divided cultures, 25 (96.2%) were identified. CONCLUSION: Salmonella sp., Escherichia coli, Shigella sp., Listeria monocytogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Proteus sp., Bacillus cereus, Vibrio cholerae, Enterococcus faecalis, Yersinia enterocolitica, and Campylobacter jejuni can be detected and identified by our microarrays. The accuracy, range, and discrimination power of this assay can be continually improved by adding further oligonucleotides to the arrays without any significant increase of complexity or cost. PMID:16437687

[Experimental rationale for the parameters of a rapid method for oxidase activity determination].

PubMed

Butorina, N N

2010-01-01

Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.

Isolation of bacteria-containing phagosomes by magnetic selection

PubMed Central

Lönnbro, Per; Nordenfelt, Pontus; Tapper, Hans

2008-01-01

Background There is a growing awareness of the importance of intracellular events in determining the outcome of infectious disease. To improve the understanding of such events, like phagosome maturation, we set out to develop a versatile technique for phagosome isolation that is rapid and widely applicable to different pathogens. Results We developed two different protocols to isolate phagosomes containing dead or live bacteria modified with small magnetic particles, in conjunction with a synchronized phagocytosis protocol and nitrogen cavitation. For dead bacteria, we performed analysis of the phagosome samples by microscopy and immunoblot, and demonstrated the appearance of maturation markers on isolated phagosomes. Conclusion We have presented detailed protocols for phagosome isolation, which can be adapted for use with different cell types and prey. The versatility and simplicity of the approach allow better control of phagosome isolation, the parameters of which are critical in studies of host-bacteria interaction and phagosome maturation. PMID:18588680

Methylotrophic bacteria in sustainable agriculture.

PubMed

Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

2016-07-01

Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

Lactic Acid Bacteria Exopolysaccharides in Foods and Beverages: Isolation, Properties, Characterization, and Health Benefits.

PubMed

Lynch, Kieran M; Zannini, Emanuele; Coffey, Aidan; Arendt, Elke K

2018-03-25

Exopolysaccharides produced by lactic acid bacteria are a diverse group of polysaccharides produced by many species. They vary widely in their molecular, compositional, and structural characteristics, including mechanisms of synthesis. The physiochemical properties of these polymers mean that they can be exploited for the sensorial and textural enhancement of a variety of food and beverage products. Traditionally, lactic acid bacteria exopolysaccharides have an important role in fermented dairy products and more recently are being applied for the improvement of bakery products. The health benefits that are continually being associated with these polysaccharides enable the development of dual function, added-value, and clean-label products. To fully exploit and understand the functionality of these exopolysaccharides, their isolation, purification, and thorough characterization are of great importance. This review considers each of the above factors and presents the current knowledge on the importance of lactic acid bacteria exopolysaccharides in the food and beverage industry.

Fortified interpenetrating polymers – bacteria resistant coatings for medical devices† †Electronic supplementary information (ESI) available: Supporting figures and tables, and additional experimental procedures. See DOI: 10.1039/c6tb01110a Click here for additional data file.

PubMed Central

Venkateswaran, Seshasailam; Henrique Dos Santos, Orlando David; Scholefield, Emma; Lilienkampf, Annamaria; Gwynne, Peter J.; Swann, David G.; Dhaliwal, Kevin

2016-01-01

Infections arising from contaminated medical devices are a serious global issue, contributing to antibiotic resistance and imposing significant strain on healthcare systems. Since the majority of medical device-associated infections are biofilm related, efforts are being made to generate either bacteria-repellent or antibacterial coatings aimed at preventing bacterial colonisation. Here, we utilise a nanocapsule mediated slow release of a natural antimicrobial to improve the performance of a bacteria repellent polymer coating. Poly(lauryl acrylate) nanocapsules containing eugenol (4-allyl-2-methoxyphenol) were prepared and entrapped within a interpenetrating network designed to repel bacteria. When coated on a catheter and an endotracheal tube, this hemocompatible system allowed slow-release of eugenol, resulting in notable reduction in surface-bound Klebsiella pneumoniae and methicillin resistant Staphylococcus aureus. PMID:27746915

Mycorrhiza helper bacteria

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

Deveau, Aurelie; Labbe, Jessy

This chapter focuses on the Mycorrhiza Helper Bacteria (MHB), a generic name given to bacteria which stimulate the formation of mycorrhizal symbiosis. By extension, some bacterial strains that positively impact the functioning of mycorrhizal symbiosis are also called MHB. These bacteria have applicative interests, as they indirectly improve the health and growth of tree seedlings. MHB are not restricted to a specific type of ecosystem, but are rather generalist in the way that they associate with both herbaceous and woody mycorrhizal plants from boreal, temperate, arid and tropical ecosystems. However, understanding the molecular mechanisms and their specificities will help usmore » to know more about the ecology of the MHB. The process of acquisition varies between fungal species; while ectomycorrhizal fungi most probably recurrently acquire them from the environment, the association between bacterial endosymbionts and Glomeromycota probably dates back to very ancient times, and has since been vertically transmitted.« less

The scourge of antibiotic resistance: the important role of the environment.

PubMed

Finley, Rita L; Collignon, Peter; Larsson, D G Joakim; McEwen, Scott A; Li, Xian-Zhi; Gaze, William H; Reid-Smith, Richard; Timinouni, Mohammed; Graham, David W; Topp, Edward

2013-09-01

Antibiotic resistance and associated genes are ubiquitous and ancient, with most genes that encode resistance in human pathogens having originated in bacteria from the natural environment (eg, β-lactamases and fluoroquinolones resistance genes, such as qnr). The rapid evolution and spread of "new" antibiotic resistance genes has been enhanced by modern human activity and its influence on the environmental resistome. This highlights the importance of including the role of the environmental vectors, such as bacterial genetic diversity within soil and water, in resistance risk management. We need to take more steps to decrease the spread of resistance genes in environmental bacteria into human pathogens, to decrease the spread of resistant bacteria to people and animals via foodstuffs, wastes and water, and to minimize the levels of antibiotics and antibiotic-resistant bacteria introduced into the environment. Reducing this risk must include improved management of waste containing antibiotic residues and antibiotic-resistant microorganisms.

Chemically individual armoured bioreporter bacteria used for the in vivo sensing of ultra-trace toxic metal ions.

PubMed

Zhang, Zhijun; Ju, Enguo; Bing, Wei; Wang, Zhenzhen; Ren, Jinsong; Qu, Xiaogang

2017-07-25

A chemically engineered armour is developed for simultaneously improving bioreporter bacterial vitality and shielding infectivity. The armour can help bacteria to resist various insults and even immune phagocytosis. Meanwhile, the bacterial infectivity has proven to be greatly shielded as well. Most importantly, the original bacterial biosensing activity is well preserved, which is competent for sensing trace arsenic in water, serum, and even in vivo.

ASSESSMENT OF SULFATE REDUCTION RATES IN LABORATORY EXPERIMENTS

EPA Science Inventory

Two successful field demonstrations of sulfate reducing bacteria (SRB) bioreactors showed needs for research: 1) improve the understanding of the processes in the bioreactor and its longetivity and 2) improve and quantify the design of the bioreactors. An important component of t...

[Assessment of hygiene practices in anaesthesia between 1998 and 2007 in Lorraine].

PubMed

Anselme, S; Boileau, S; Vedel, M; Muller, C; Blech, M-F; Bouaziz, H

2009-01-01

To study the assessment of hygiene practices in anaesthesia in Lorraine between 1998 and 2007, after recommendations from the French Society of Anaesthesia and Reanimation (SFAR) in December 1997, and different local actions. Two surveys performed at a nine-year interval in Lorraine hospitals. Questionnaires about risk infection management and hygiene practices were sent by post to all anaesthetists, nurse anaesthetists and recovery room nurses in 1998 (n=279) and in 2007 (n=259). Between the two surveys multidrug-resistant bacteria signalling, movements of the staff in operating rooms, septic isolation protocol and management of single-use disposable anaesthesia material have been improved (p<0.05). Central venous catheters are less performed in recovery rooms and rings wearing decreased by 16% (p<0.05). Wearing of nonsterile gloves for peripheral venous catheter and intubation is not generalized (p<0.05). About half of the hospitals have cleanup procedures of anaesthesia furniture. Washing of hands by anaesthesia staff is not sometimes respected but it's more frequent for medicine preparation and between two operations. A good skin disinfection (cleaning - rinsing - drying - antiseptic) is more recurrent in 2007 (61.4%) than in 1998 (41.9%) for arterial catheter. Wearing of glasses for intubation is each times rare, about 15%. Hygiene practices in anaesthesia in Lorraine have been improved between the two surveys by recommendations from the Sfar and the work of the Antenne Régional de Lorraine (audits, manuals, formations). Promising progress has been made but some points must still be worked on.

An interval programming model for continuous improvement in micro-manufacturing

NASA Astrophysics Data System (ADS)

Ouyang, Linhan; Ma, Yizhong; Wang, Jianjun; Tu, Yiliu; Byun, Jai-Hyun

2018-03-01

Continuous quality improvement in micro-manufacturing processes relies on optimization strategies that relate an output performance to a set of machining parameters. However, when determining the optimal machining parameters in a micro-manufacturing process, the economics of continuous quality improvement and decision makers' preference information are typically neglected. This article proposes an economic continuous improvement strategy based on an interval programming model. The proposed strategy differs from previous studies in two ways. First, an interval programming model is proposed to measure the quality level, where decision makers' preference information is considered in order to determine the weight of location and dispersion effects. Second, the proposed strategy is a more flexible approach since it considers the trade-off between the quality level and the associated costs, and leaves engineers a larger decision space through adjusting the quality level. The proposed strategy is compared with its conventional counterparts using an Nd:YLF laser beam micro-drilling process.

NASA Launches CubeSat to Study Bacteria in Space

NASA Image and Video Library

2017-11-08

Ever wonder what would happen if you got sick in space? NASA is sending samples of bacteria into low-Earth orbit to find out. One of the latest small satellite missions from NASA’s Ames Research Center in California’s Silicon Valley is the E. coli Anti-Microbial Satellite, or EcAMSat for short. This CubeSat – a spacecraft the size of a shoebox built from cube-shaped units – will explore how effectively antibiotics can combat E. coli bacteria in the low gravity of space. This information will help us improve how we fight infections, providing safer journeys for astronauts on their future voyages, and offer benefits for medicine here on Earth.

Confidence intervals and sample size calculations for the standardized mean difference effect size between two normal populations under heteroscedasticity.

PubMed

Shieh, G

2013-12-01

The use of effect sizes and associated confidence intervals in all empirical research has been strongly emphasized by journal publication guidelines. To help advance theory and practice in the social sciences, this article describes an improved procedure for constructing confidence intervals of the standardized mean difference effect size between two independent normal populations with unknown and possibly unequal variances. The presented approach has advantages over the existing formula in both theoretical justification and computational simplicity. In addition, simulation results show that the suggested one- and two-sided confidence intervals are more accurate in achieving the nominal coverage probability. The proposed estimation method provides a feasible alternative to the most commonly used measure of Cohen's d and the corresponding interval procedure when the assumption of homogeneous variances is not tenable. To further improve the potential applicability of the suggested methodology, the sample size procedures for precise interval estimation of the standardized mean difference are also delineated. The desired precision of a confidence interval is assessed with respect to the control of expected width and to the assurance probability of interval width within a designated value. Supplementary computer programs are developed to aid in the usefulness and implementation of the introduced techniques.

Effects of High-Intensity Interval Training on Aerobic Capacity in Cardiac Patients: A Systematic Review with Meta-Analysis

PubMed Central

Xie, Bin; Yan, Xianfeng

2017-01-01

Purpose. The aim of this study was to compare the effects of high-intensity interval training (INTERVAL) and moderate-intensity continuous training (CONTINUOUS) on aerobic capacity in cardiac patients. Methods. A meta-analysis identified by searching the PubMed, Cochrane Library, EMBASE, and Web of Science databases from inception through December 2016 compared the effects of INTERVAL and CONTINUOUS among cardiac patients. Results. Twenty-one studies involving 736 participants with cardiac diseases were included. Compared with CONTINUOUS, INTERVAL was associated with greater improvement in peak VO2 (mean difference 1.76 mL/kg/min, 95% confidence interval 1.06 to 2.46 mL/kg/min, p < 0.001) and VO2 at AT (mean difference 0.90 mL/kg/min, 95% confidence interval 0.0 to 1.72 mL/kg/min, p = 0.03). No significant difference between the INTERVAL and CONTINUOUS groups was observed in terms of peak heart rate, peak minute ventilation, VE/VCO2 slope and respiratory exchange ratio, body mass, systolic or diastolic blood pressure, triglyceride or low- or high-density lipoprotein cholesterol level, flow-mediated dilation, or left ventricular ejection fraction. Conclusions. This study showed that INTERVAL improves aerobic capacity more effectively than does CONTINUOUS in cardiac patients. Further studies with larger samples are needed to confirm our observations. PMID:28386556

Frequent contamination of nursing scrubs is associated with specific care activities.

PubMed

Thom, Kerri A; Escobar, Daniel; Boutin, Mallory A; Zhan, Min; Harris, Anthony D; Johnson, J Kristie

2018-05-01

The objective of this article is to assess health care worker (HCW) and patient care factors associated with bacterial contamination of scrubs. We performed a cohort study of critical care HCWs. Participants were given 4 sets of new scrubs; each set was sampled 8 times during the 8-month study period on random days in the last 4 hours of the shift. Total colony counts and presence of prespecified pathogenic bacteria were assessed. Generalized estimating equation was used to identify factors associated with contamination. There were 720 samples obtained from 90 HCWs; 30% of samples were contaminated with pathogenic bacteria. Multivariate analysis showed that providing care for patients with wounds (odds ratio [OR], 1.75; 95% confidence interval [CI], 1.17-2.62; P < .01) or giving a bath (OR, 1.46; 95% CI, 0.96-2.22; P = .07) was associated with higher odds of scrub contamination. A second model showed the average log colony count of bacterial contamination of scrubs was higher when a bath was given (log colony count difference, 0.21; P = .05) but lower among HCWs assigned to care for at least 1 patient on contact precautions (log colony count difference, 0.28; P < .01). HCW attire was frequently contaminated with bacteria. Providing care for patients with wounds or giving a bath were associated with scrub contamination by pathogenic bacteria. However, the amount of contamination was lower among HCWs who were assigned to care for patients on contact precautions. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Rumen microbial changes in cattle fed diets with or without salinomycin.

PubMed

Olumeyan, D B; Nagaraja, T G; Miller, G W; Frey, R A; Boyer, J E

1986-02-01

Four rumen-fistulated steers, randomly assigned to two groups (control and salinomycin fed) were used to monitor the changes in rumen microbial populations and volatile fatty acids (VFA) concentrations associated with feeding salinomycin (0.22 mg X kg-1 X day-1). Steers were adapted to an alfalfa hay and grain (80:20) diet before supplementing the diet with salinomycin, and then the diet was changed to 50:50 and 20:80 ratios of alfalfa hay to grain at 2-week intervals. Rumen samples for total and selective enumeration of anaerobic bacteria. VFA analysis, and enumeration of protozoa were collected during the 80:20 alfalfa hay-to-grain diet before salinomycin feeding, and during the 80:20, 50:50, and 20:80 hay-to-grain diets with salinomycin. At each sampling period, rumen samples were collected at 3 h after feeding on three consecutive days. Salinomycin feeding had no effect on rumen pH and total VFA concentration. The acetate-to-propionate ratio was significantly lower in salinomycin-fed steers than in the control. The molar proportion of butyrate increased in both control and salinomycin-fed steers. Total anaerobic bacterial counts were lower in salinomycin-fed steers than in the control steers after 8 weeks of salinomycin feeding. Salinomycin-resistant bacteria increased from 7.6 to 15.6% in salinomycin-fed steers but remained unchanged in control steers. Salinomycin had no effect on cellulolytic and lactate-utilizing bacteria, but the proportion of amylolytic bacteria was higher in salinomycin-fed steers than in control steers. The total number of protozoa decreased initially in salinomycin-fed steers. The initial reduction was due to reduced numbers of Entodinium species. Holotrichs were unaffected by salinomycin feeding.

Microbial biomass and productivity in seagrass beds

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

Moriarty, P.J.W.; Boon, P.I.; Hansen, J.A.

1985-01-01

Different methods for measuring the rates of processes mediated by bacteria in sediments and the rates of bacterial cell production have been compared. In addition, net production of the seagrass Zostera capricorni and bacterial production have been compared and some interrelationships with the nitrogen cycle discussed. Seagrass productivity was estimated by measuring the plastochrone interval using a leaf stapling technique. The average productivity over four seasons was 1.28 +- 0.28 g C/m/sup 2/ day (meand +- standard deviation, n = 4). Bacterial productivity was measured five times throughout a year using the rate of tritiated thymidine incorporated into DNA. Averagemore » values were 33 +- 12 mg C/m/sup 2/ day for sediment and 23 +- 4 for water column (n = 5). Spatial variability between samples was greater than seasonal variation for both seagrass productivity and bacterial productivity. On one occasion, bacterial productivity was measured using the rate of /sup 32/P incorporated into phospholipid. The values were comparable to those obtained with tritiated thymidine. The rate of sulfate reduction was 10 mmol SO/sub 4//m/sup 2/ day. The rate of methanogenesis was low, being 5.6 mg CH/sub 4/ produced/m/sup 2/ day. A comparison of C flux measured using rates of sulfate reduction and DNA synthesis indicated that anaerobic processes were predominant in these sediments. An analysis of microbial biomass and community structure, using techniques of phospholipid analysis, showed that bacteria were predominant members of the microbial biomass and that of these strictly anaerobic bacteria were the main components. Ammonia concentration in interstitial water varied from 23 to 71 ..mu..M. Estimates of the amount of ammonia required by seagrass showed that the ammonia would turn over about once per day. Rapid recycling of nitrogen by bacteria and bacterial grazers is probably important.« less

A novel method for bacterial inactivation using electrosprayed water nanostructures

NASA Astrophysics Data System (ADS)

Pyrgiotakis, Georgios; McDevitt, James; Yamauchi, Toshiyuki; Demokritou, Philip

2012-08-01

This is a study focusing on the potential to deactivate biological agents (bacteria and endospores) using engineered water nanostructures (EWNS). The EWNS were generated using an electrospray device that collects water by condensing atmospheric water vapor on a Peltier-cooled electrode. A high voltage is applied between the collection electrode and a grounded electrode resulting in aerosolization of the condensed water and a constant generation of EWNS. Gram-negative Serratia marcescens, gram-positive Staphylococcus aureus, and Bacillus atrophaeus endospores were placed on stainless steel coupons and exposed to generated EWNS at multiple time intervals. Upon exposures, the bacteria were recovered and placed on nutrient agar to grow, and the colony forming units were counted. Ozone levels as well as air temperature and relative humidity were monitored during the experiments. Qualitative confirmation of bacterial destruction was also obtained by transmission electron microscopy. In addition, important EWNS aerosol properties such as particle number concentration as a function of size as well as the average surface charge of the generated EWNS were measured using real-time instrumentation. It was shown that the novel electrospray method can generate over time a constant flux of EWNS. EWNS have a peak number concentration of 8,000 particles per cubic centimeter with a modal peak size around 20 nm. The average surface charge of the generated EWNS was found to be 10 ± 2 electrons per particle. In addition, it was shown that the EWNS have the potential to deactivate both bacteria types from surfaces. At the same administrate dose, however, the endospores were not inactivated. This novel method and the unique properties of the generated EWNS could potentially be used to develop an effective, environmentally friendly, and inexpensive method for bacteria inactivation.

Impact of universal gowning and gloving on health care worker clothing contamination.

PubMed

Williams, Calvin; McGraw, Patty; Schneck, Elyse E; LaFae, Anna; Jacob, Jesse T; Moreno, Daniela; Reyes, Katherine; Cubillos, G Fernando; Kett, Daniel H; Estrella, Ronald; Morgan, Daniel J; Harris, Anthony D; Drees, Marci

2015-04-01

To determine whether gowning and gloving for all patient care reduces contamination of healthcare worker (HCW) clothing, compared to usual practice. Cross-sectional surveys. Five study sites were recruited from intensive care units (ICUs) randomized to the intervention arm of the Benefits of Universal Gown and Glove (BUGG) study. All HCWs performing direct patient care in the study ICUs were eligible to participate. Surveys were performed first during the BUGG intervention study period (July-September 2012) with universal gowning/gloving and again after BUGG study conclusion (October-December 2012), with resumption of usual care. During each phase, HCW clothing was sampled at the beginning and near the end of each shift. Cultures were performed using broth enrichment followed by selective media. Acquisition was defined as having a negative clothing culture for samples taken at the beginning of a shift and positive clothing culture at for samples taken at the end of the shift. A total of 348 HCWs participated (21-92 per site), including 179 (51%) during the universal gowning/gloving phase. Overall, 51 (15%) HCWs acquired commonly pathogenic bacteria on their clothing: 13 (7.1%) HCWs acquired bacteria during universal gowning/gloving, and 38 (23%) HCWs acquired bacteria during usual care (odds ratio [OR], 0.3; 95% confidence interval [CI], 0.2-0.6). Pathogens identified included S. aureus (25 species, including 7 methicillin-resistant S. aureus [MRSA]), Enterococcus spp. (25, including 1 vancomycin-resistant Enterococcus [VRE]), Pseudomonas spp. (4), Acinetobacter spp. (4), and Klebsiella (2). Nearly 25% of HCWs practicing usual care (gowning and gloving only for patients with known resistant bacteria) contaminate their clothing during their shift. This contamination was reduced by 70% by gowning and gloving for all patient interactions.

The application of amplicon length heterogeneity PCR (LH-PCR) for monitoring the dynamics of soil microbial communities associated with cadaver decomposition.

PubMed

Moreno, Lilliana I; Mills, DeEtta; Fetscher, Jill; John-Williams, Krista; Meadows-Jantz, Lee; McCord, Bruce

2011-03-01

The placement of cadavers in shallow, clandestine graves may alter the microbial and geochemical composition of the underlying and adjacent soils. Using amplicon length heterogeneity-PCR (LH-PCR) the microbial community changes in these soils can be assessed. In this investigation, nine different grave sites were examined over a period of 16weeks. The results indicated that measurable changes occurred in the soil bacterial community during the decomposition process. In this study, amplicons corresponding to anaerobic bacteria, not indigenous to the soil, were shown to produce differences between grave sites and control soils. Among the bacteria linked to these amplicons are those that are most often part of the commensal flora of the intestines, mouth and skin. In addition, over the 16week sampling interval, the level of indicator organisms (i.e., nitrogen fixing bacteria) dropped as the body decomposed and after four weeks of environmental exposure they began to increase again; thus differences in the abundance of nitrogen fixing bacteria were also found to contribute to the variation between controls and grave soils. These results were verified using primers that specifically targeted the nifH gene coding for nitrogenase reductase. LH-PCR provides a fast, robust and reproducible method to measure microbial changes in soil and could be used to determine potential cadaveric contact in a given area. The results obtained with this method could ultimately provide leads to investigators in criminal or missing person scenarios and allow for further analysis using human specific DNA assays to establish the identity of the buried body. Copyright © 2010 Elsevier B.V. All rights reserved.

Influence of various scavengers of •OH radicals on the radiation sensitivity of yeast and bacteria.

PubMed

Múčka, Viliam; Bláha, Pavel; Čuba, Václav; Červenák, Jaroslav

2013-12-01

To quantitatively investigate the influence of various •OH (hydroxyl radical) scavengers on the radiation sensitivity of yeast and bacteria, particularly to define the relationship between the protective effect of a scavenger and its •OH scavenging efficiency. In order to study the protective effect of •OH scavengers we used various concentrations of four scavengers (methanol, potassium formate, ethanol and ascorbic acid) in isotonic salt solutions. These solutions containing live yeast (Saccharomyces cerevisiae) or bacteria (Escherichia coli) were irradiated with (60)Co isotope γ -radiation using two different doses and dose rates. The number of surviving cells was determined prior to and after irradiation both in suspension with and without scavengers. The surviving fractions after irradiation with and without the scavenger were evaluated. The main results of the paper were: The surviving fraction increased approximately linearly within the measured interval with increasing concentration of the scavenger. The same dependences were found for the protecting effect depending on the scavenging efficiency. The slopes of these dependences (k) were found to be characteristic for each scavenger. The k value determined the degree in which the scavenging of •OH radicals participated in the protection of living cells. The protective effects of scavengers at the same scavenging efficiency were different and unique for each scavenger. No simple relation was found between the efficiency of scavenger k and the rate constant kOH of the reactions between scavengers and •OH radicals. Our results suggest that the studied scavengers effectively protected yeast and bacteria against ionizing radiation. Although the scavenging of •OH radicals seems to be important for protection of living cells, it is clearly not the only process on which the protection is based.

Evolution of Mudstone Porosity, Permeability, and Microstructure in the Presence of Microorganisms During Vertical Compression

NASA Astrophysics Data System (ADS)

Mills, T.; Reece, J. S.

2016-12-01

Here we investigate the influence of microbial activity on the mechanical and transport properties of mudstones during early diagenesis. Despite the proven presence of microbial communities in marine sediments to depths of >500 meters below sea floor (mbsf), little is known about the interactions between microorganisms and sediments, especially during the early stages of burial and compression. To characterize and quantify the impact of microbial activity on mudstone properties, we compare natural mudstone samples treated with iron reducing bacteria Shewanella Oneidensis MR-1 and those without bacteria. Two bulk mudstones are experimentally prepared using sediments from Integrated Ocean Drilling Program Sites U1319 and U1324 in the Gulf of Mexico. The sediments originated from 4-13 mbsf in the Brazos-Trinity Basin and from three depth intervals (3-14 mbsf, 23-32 mbsf, and 493-502 mbsf) in the Ursa Basin. The sediments are dried and ground to clay- and silt-sized particles and homogenized into two natural mudstone powders. These powders are then used to make reproducible mudstone samples through a process called resedimentation, which replicates natural deposition and burial. Changes in microstructure, porosity, compressibility, and permeability are measured while the biotic (with bacteria) and abiotic (without bacteria) mudstones are being uniaxially compressed over several weeks to a maximum stress of 100 kPa. We anticipate that biofilm growth in pore spaces will decrease porosity, compressibility, and permeability, and the resultant microstructural changes created by microorganisms will be evident in high-resolution scanning electron microscope (SEM) images. Recognition of the micro-scale processes that take place during the early stages of mudstone diagenesis, especially those mediated by microbial activity, and their long-term effects on mudstone properties can lead to better identification and more effective production of unconventional hydrocarbon reservoirs.

Microbial biomass and productivity in seagrass beds

NASA Technical Reports Server (NTRS)

Moriarty, D. J.; Boon, P. I.; Hansen, J. A.; Hunt, W. G.; Poiner, I. R.; Pollard, P. C.; Skyring, G. W.; White, D. C.

1985-01-01

Different methods for measuring the rates of processes mediated by bacteria in sediments and the rates of bacterial cell production have been compared. In addition, net production of the seagrass Zostera capricorni and bacterial production have been compared and some interrelationships with the nitrogen cycle discussed. Seagrass productivity was estimated by measuring the plastochrone interval using a leaf stapling technique. The average productivity over four seasons was 1.28 +/- 0.28 g C m-2 day-1 (mean +/- standard deviation, n = 4). Bacterial productivity was measured five times throughout a year using the rate of tritiated thymidine incorporated into DNA. Average values were 33 +/- 12 mg C m-2 day-1 for sediment and 23 +/- 4 for water column (n = 5). Spatial variability between samples was greater than seasonal variation for both seagrass productivity and bacterial productivity. On one occasion, bacterial productivity was measured using the rate of 32P incorporated into phospholipid. The values were comparable to those obtained with tritiated thymidine. The rate of sulfate reduction was 10 mmol SO4(-2) m-2 day-1. The rate of methanogenesis was low, being 5.6 mg CH4 produced m-2 day-1. A comparison of C flux measured using rates of sulfate reduction and DNA synthesis indicated that anaerobic processes were predominant in these sediments. An analysis of microbial biomass and community structure, using techniques of phospholipid analysis, showed that bacteria were predominant members of the microbial biomass and that of these, strictly anaerobic bacteria were the main components. Ammonia concentration in interstitial water varied from 23 to 71 micromoles. Estimates of the amount of ammonia required by seagrass showed that the ammonia would turn over about once per day. Rapid recycling of nitrogen by bacteria and bacterial grazers is probably important.

The effect of adding selective mixed culture of alternative electricity production based on tempe wastewater on tubular microbial fuel cell

NASA Astrophysics Data System (ADS)

Mariana, Elisabeth, Utami, Tania Surya; Arbianti, Rita; Hermansyah, Heri

2017-05-01

Bacteria has long been known could produce electricity. MFC (Microbial Fuel Cell) is a technology that uses bacteria. MFC is potential as producer of alternative renewable energy through the conversion of waste by bacteria into electrical energy. However, this technology cannot reach the target value of the minimum voltage. This research is focused on reviewing the effect of the addition of gram positive and negative bacteria (selective mixed culture) contained in tempe wastewater as well as the optimal volume additions gram using a tubular single chamber membranless reactor. The result shows that the addition of selective mixed culture can increase voltage of MFC. Gram negative bacteria dominate tempe wastewater and has better ability to transfer electrons than gram-positive. The voltage increases with increasing amount of bacteria up to a certain maximum point. Addition of 1 mL gram-negative bacteria improve electrical output and provide the most optimal results of 0.0697 mW/m2 mV or 92.14% excalation against the initial control experiment with the average power density of 0.0702 mW1m2. Additions of most optimum variation also give good results on the use of industrial waste, with electrical voltage and power density high of 8.90 mV and 0.02 mW/m2.

Reduced short interval cortical inhibition correlates with atomoxetine response in children with attention-deficit hyperactivity disorder (ADHD).

PubMed

Chen, Tina H; Wu, Steve W; Welge, Jeffrey A; Dixon, Stephan G; Shahana, Nasrin; Huddleston, David A; Sarvis, Adam R; Sallee, Floyd R; Gilbert, Donald L

2014-12-01

Clinical trials in children with attention-deficit hyperactivity disorder (ADHD) show variability in behavioral responses to the selective norepinephrine reuptake inhibitor atomoxetine. The objective of this study was to determine whether transcranial magnetic stimulation-evoked short interval cortical inhibition might be a biomarker predicting, or correlating with, clinical atomoxetine response. At baseline and after 4 weeks of atomoxetine treatment in 7- to 12-year-old children with ADHD, transcranial magnetic stimulation short interval cortical inhibition was measured, blinded to clinical improvement. Primary analysis was by multivariate analysis of covariance. Baseline short interval cortical inhibition did not predict clinical responses. However, paradoxically, after 4 weeks of atomoxetine, mean short interval cortical inhibition was reduced 31.9% in responders and increased 6.1% in nonresponders (analysis of covariance t 41 = 2.88; P = .0063). Percentage reductions in short interval cortical inhibition correlated with reductions in the ADHD Rating Scale (r = 0.50; P = .0005). In children ages 7 to 12 years with ADHD treated with atomoxetine, improvements in clinical symptoms are correlated with reductions in motor cortex short interval cortical inhibition. © The Author(s) 2014.

Drought-Tolerance of Wheat Improved by Rhizosphere Bacteria from Harsh Environments: Enhanced Biomass Production and Reduced Emissions of Stress Volatiles

PubMed Central

Timmusk, Salme; Abd El-Daim, Islam A.; Copolovici, Lucian; Tanilas, Triin; Kännaste, Astrid; Behers, Lawrence; Nevo, Eviatar; Seisenbaeva, Gulaim; Stenström, Elna; Niinemets, Ülo

2014-01-01

Water is the key resource limiting world agricultural production. Although an impressive number of research reports have been published on plant drought tolerance enhancement via genetic modifications during the last few years, progress has been slower than expected. We suggest a feasible alternative strategy by application of rhizospheric bacteria coevolved with plant roots in harsh environments over millions of years, and harboring adaptive traits improving plant fitness under biotic and abiotic stresses. We show the effect of bacterial priming on wheat drought stress tolerance enhancement, resulting in up to 78% greater plant biomass and five-fold higher survivorship under severe drought. We monitored emissions of seven stress-related volatiles from bacterially-primed drought-stressed wheat seedlings, and demonstrated that three of these volatiles are likely promising candidates for a rapid non-invasive technique to assess crop drought stress and its mitigation in early phases of stress development. We conclude that gauging stress by elicited volatiles provides an effectual platform for rapid screening of potent bacterial strains and that priming with isolates of rhizospheric bacteria from harsh environments is a promising, novel way to improve plant water use efficiency. These new advancements importantly contribute towards solving food security issues in changing climates. PMID:24811199

Broad Specificity Efflux pumps and Their Role in Multidrug Resistance of Gram Negative Bacteria

PubMed Central

Nikaido, Hiroshi; Pagès, Jean-Marie

2013-01-01

Antibiotic resistance mechanisms reported in Gram-negative bacteria are producing a worldwide health problem. The continuous dissemination of «multi-drug resistant» (MDR) bacteria drastically reduces the efficacy of our antibiotic “arsenal” and consequently increases the frequency of therapeutic failure. In MDR bacteria, the over-expression of efflux pumps that expel structurally-unrelated drugs contributes to the reduced susceptibility by decreasing the intracellular concentration of antibiotics. During the last decade, several clinical data indicate an increasing involvement of efflux pumps in the emergence and dissemination of resistant Gram-negative bacteria. It is necessary to clearly define the molecular, functional and genetic bases of the efflux pump in order to understand the translocation of antibiotic molecules through the efflux transporter. The recent investigation on the efflux pump AcrB at its structural and physiological level, including the identification of drug affinity sites and kinetic parameters for various antibiotics, may open the way to rationally develop an improved new generation of antibacterial agents as well as efflux inhibitors in order to efficiently combat efflux-based resistance mechanisms. PMID:21707670

Sweet scents from good bacteria: Case studies on bacterial volatile compounds for plant growth and immunity.

PubMed

Chung, Joon-hui; Song, Geun Cheol; Ryu, Choong-Min

2016-04-01

Beneficial bacteria produce diverse chemical compounds that affect the behavior of other organisms including plants. Bacterial volatile compounds (BVCs) contribute to triggering plant immunity and promoting plant growth. Previous studies investigated changes in plant physiology caused by in vitro application of the identified volatile compounds or the BVC-emitting bacteria. This review collates new information on BVC-mediated plant-bacteria airborne interactions, addresses unresolved questions about the biological relevance of BVCs, and summarizes data on recently identified BVCs that improve plant growth or protection. Recent explorations of bacterial metabolic engineering to alter BVC production using heterologous or endogenous genes are introduced. Molecular genetic approaches can expand the BVC repertoire of beneficial bacteria to target additional beneficial effects, or simply boost the production level of naturally occurring BVCs. The effects of direct BVC application in soil are reviewed and evaluated for potential large-scale field and agricultural applications. Our review of recent BVC data indicates that BVCs have great potential to serve as effective biostimulants and bioprotectants even under open-field conditions.

SERS as analytical tool for detection of bacteria

NASA Astrophysics Data System (ADS)

Cialla, Dana; Rösch, Petra; Möller, Robert; Popp, Jürgen

2007-07-01

The detection of single bacteria should be improved by lowering the acquisition time via the application of SERS (surface enhanced Raman spectroscopy). Nano structured colloids or surfaces consisting of gold or silver can be used as SERS active substrates. However, for biological applications mostly gold is used as SERS active substrate since silver is toxic for bacterial cells. Furthermore, the application of gold as a SERS-active substrate allows the usage of Raman excitation wavelengths in the red part of the electromagnetic spectrum. For the SERS investigations on bacteria different colloids (purchased and self prepared, preaggregated and non-aggregated) are chosen as SERS active substrates. The application of different gold colloids under gently mixing conditions to prevent the bacterial damage allowed the recording of reproducible SERS spectra of bacteria. The SERS spectra of B. pumilus are dominated by contributions of ingredients of the outer cell wall, e.g. the peptidoglycan layer. SEM images of the coated bacteria demonstrate the incomplete adsorption most probably due to variations within the binding affinities between different outer cell components and the gold colloids.

Sulfur-oxidizing bacteria dominate the microbial diversity shift during the pyrite and low-grade pyrolusite bioleaching process.

PubMed

Han, Yifan; Ma, Xiaomei; Zhao, Wei; Chang, Yunkang; Zhang, Xiaoxia; Wang, Xingbiao; Wang, Jingjing; Huang, Zhiyong

2013-10-01

The microbial ecology of the pyrite-pyrolusite bioleaching system and its interaction with ore has not been well-described. A 16S rRNA gene clone library was created to evaluate changes in the microbial community at different stages of the pyrite-pyrolusite bioleaching process in a shaken flask. The results revealed that the bacterial community was disturbed after 5 days of the reaction. Phylogenetic analysis of 16S rRNA sequences demonstrated that the predominant microorganisms were members of a genus of sulfur-oxidizing bacteria, Thiomonas sp., that subsequently remained dominant during the bioleaching process. Compared with iron-oxidizing bacteria, sulfur-oxidizing bacteria were more favorable to the pyrite-pyrolusite bioleaching system. Decreased pH due to microbial acid production was an important condition for bioleaching efficiency. Iron-oxidizing bacteria competed for pyrite reduction power with Mn(IV) in pyrolusite under specific conditions. These results extend our knowledge of microbial dynamics during pyrite-pyrolusite bioleaching, which is a key issue to improve commercial applications. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Acetic acid bacteria: A group of bacteria with versatile biotechnological applications.

PubMed

Saichana, Natsaran; Matsushita, Kazunobu; Adachi, Osao; Frébort, Ivo; Frebortova, Jitka

2015-11-01

Acetic acid bacteria are gram-negative obligate aerobic bacteria assigned to the family Acetobacteraceae of Alphaproteobacteria. They are members of the genera Acetobacter, Gluconobacter, Gluconacetobacter, Acidomonas, Asaia, Kozakia, Swaminathania, Saccharibacter, Neoasaia, Granulibacter, Tanticharoenia, Ameyamaea, Neokomagataea, and Komagataeibacter. Many strains of Acetobacter and Komagataeibacter have been known to possess high acetic acid fermentation ability as well as the acetic acid and ethanol resistance, which are considered to be useful features for industrial production of acetic acid and vinegar, the commercial product. On the other hand, Gluconobacter strains have the ability to perform oxidative fermentation of various sugars, sugar alcohols, and sugar acids leading to the formation of several valuable products. Thermotolerant strains of acetic acid bacteria were isolated in order to serve as the new strains of choice for industrial fermentations, in which the cooling costs for maintaining optimum growth and production temperature in the fermentation vessels could be significantly reduced. Genetic modifications by adaptation and genetic engineering were also applied to improve their properties, such as productivity and heat resistance. Copyright © 2014 Elsevier Inc. All rights reserved.

Isolation and characterization of plant growth promoting endophytic diazotrophic bacteria from Korean rice cultivars.

PubMed

Ji, Sang Hye; Gururani, Mayank Anand; Chun, Se-Chul

2014-01-20

We have isolated 576 endophytic bacteria from the leaves, stems, and roots of 10 rice cultivars and identified 12 of them as diazotrophic bacteria using a specific primer set of nif gene. Through 16S rDNA sequence analysis, nifH genes were confirmed in the two species of Penibacillus, three species of Microbacterium, three Bacillus species, and four species of Klebsiella. Rice seeds treated with these plant growth-promoting bacteria (PGPB) showed improved plant growth, increased height and dry weight and antagonistic effects against fungal pathogens. In addition, auxin and siderophore producing ability, and phosphate solubilizing activity were studied for the possible mechanisms of plant growth promotion. Among 12 isolates tested, 10 strains have shown higher auxin producing activity, 6 isolates were confirmed as strains with high siderophore producing activity while 4 isolates turned out to have high phosphate-solubilizing activity. These results strongly suggest that the endophytic diazotrophic bacteria characterized in this study could be successfully used to promote plant growth and inducing fungal resistance in plants. Copyright © 2013 Elsevier GmbH. All rights reserved.

Effects of High Intensity Interval Training on Increasing Explosive Power, Speed, and Agility

NASA Astrophysics Data System (ADS)

Fajrin, F.; Kusnanik, N. W.; Wijono

2018-01-01

High Intensity Interval Training (HIIT) is a type of exercise that combines high-intensity exercise and low intensity exercise in a certain time interval. This type of training is very effective and efficient to improve the physical components. The process of improving athletes achievement related to how the process of improving the physical components, so the selection of a good practice method will be very helpful. This study aims to analyze how is the effects of HIIT on increasing explosive power, speed, and agility. This type of research is quantitative with quasi-experimental methods. The design of this study used the Matching-Only Design, with data analysis using the t-test (paired sample t-test). After being given the treatment for six weeks, the results showed there are significant increasing in explosive power, speed, and agility. HIIT in this study used a form of exercise plyometric as high-intensity exercise and jogging as mild or moderate intensity exercise. Increase was due to the improvement of neuromuscular characteristics that affect the increase in muscle strength and performance. From the data analysis, researchers concluded that, Exercises of High Intensity Interval Training significantly effect on the increase in Power Limbs, speed, and agility.

Mg2+ improves the thermotolerance of probiotic Lactobacillus rhamnosus GG, Lactobacillus casei Zhang and Lactobacillus plantarum P-8.

PubMed

Yang, Y; Huang, S; Wang, J; Jan, G; Jeantet, R; Chen, X D

2017-04-01

Food-related carbohydrates and proteins are often used as thermoprotectants for probiotic lactobacilli during industrial production and processing. However, the effect of inorganic salts is rarely reported. Magnesium is the second-most abundant cation in bacteria, and commonly found in various foods. Mg 2+ homeostasis is important in Salmonella and has been reported to play a critical role in their thermotolerance. However, the role of Mg 2+ in thermotolerance of other bacteria, in particular probiotic bacteria, still remains a hypothesis. In this study, the effect of Mg 2+ on thermotolerance of probiotic lactobacilli was investigated in three well-documented probiotic strains, Lactobacillus rhamnosus GG, Lactobacillus casei Zhang and Lactobacillus plantarum P-8, in comparison with Zn 2+ and Na + . Concentrations of Mg 2+ between 10 and 50 mmol l -1 were found to increase the bacterial survival upon heat challenge. Remarkably, Mg 2+ addition at 20 mmol l -1 led to a 100-fold higher survival of L. rhamnosus GG upon heat challenge. This preliminary study also showed that Mg 2+ shortened the heat-induced extended lag time of bacteria, which indicated the improvement in bacterial recovery from thermal injury. In order to improve the productivity and stability of live probiotics, extensive investigations have been carried out to improve thermotolerance of probiotics. However, most of these studies focused on the effects of carbohydrates, proteins or amino acids. The roles of inorganic salts in various food materials, which have rarely been reported, should be considered when incorporating probiotics into these foods. In this study, Mg 2+ was found to play a significant role in the thermotolerance of probiotic lactobacilli. A novel strategy may be available in the near future by employing magnesium salts as protective agents of probiotics during manufacturing process. © 2017 The Society for Applied Microbiology.

Relations of changes in wastewater-treatment practices to changes in stream-water quality during 1978-88 in the Chicago area, Illinois, and implications for regional and national water-quality assessments

USGS Publications Warehouse

Terrio, P.J.

1994-01-01

A study in the upper Illinois River Basin defined relations between changes in wastewater-treatment practices and changes in stream-water quality on the basis of available information. These relations were examined for five large wastewater-treatment plants in the Chicago area, Illinois. At the three largest treatment plants, two major changes in wastewater-treatment practices were identified--the cessation of chlorination and the implementation of Chicago's Tunnel and Reservoir Plan (TARP). Other changes, such as improved aeration and expansion of the facilities, also were made at some of the treatment plants. At the Calumet Water Reclamation Plant, median densities of fecal coliform bacteria in the effluent increased from 3,100 to 1,200,000 colonies per 100 milliliters after the cessation of chlorination. Median densities at the nearest downstream monitoring site increased from 9,500 to 250,000 colonies per 100 milliliters. Similar changes in bacteria densities were indicated for other treatment plants and stream-monitoring sites, but increases in densities of fecal coliform bacteria were not indicated at distances greater than 7 miles downstream. Substantial changes in effluent and stream-water quality, primarily improvements, were identified after the implemen- of TARP and improvements in aeration. Decreases in some of the largest concentrations of ammonia were particularly notable and were likely results of the cape and treatment of combined sewer overflows by TARP. Improvements in water quality were commonly related to climatic season, with greater changes taking place during warm periods. Substantial decreases in concentrations were identified for many constituents, including oxygen demand, ammonia, bacteria, and cyanide. The water-quality data available for this study were considered to be more accurate and were more comprehensive than data from most other monitoring programs. The results of this study, however, identified some needed enhancements to increase the usefulness of the data for additional purposes and analyses.

Bacterial polyextremotolerant bioemulsifiers from arid soils improve water retention capacity and humidity uptake in sandy soil.

PubMed

Raddadi, Noura; Giacomucci, Lucia; Marasco, Ramona; Daffonchio, Daniele; Cherif, Ameur; Fava, Fabio

2018-05-31

Water stress is a critical issue for plant growth in arid sandy soils. Here, we aimed to select bacteria producing polyextremotolerant surface-active compounds capable of improving water retention and humidity uptake in sandy soils. From Tunisian desert and saline systems, we selected eleven isolates able to highly emulsify different organic solvents. The bioemulsifying activities were stable with 30% NaCl, at 4 and 120 °C and in a pH range 4-12. Applications to a sandy soil of the partially purified surface-active compounds improved soil water retention up to 314.3% compared to untreated soil. Similarly, after 36 h of incubation, the humidity uptake rate of treated sandy soil was up to 607.7% higher than untreated controls. Overall, results revealed that polyextremotolerant bioemulsifiers of bacteria from arid and desert soils represent potential sources to develop new natural soil-wetting agents for improving water retention in arid soils.

Bioinactivation: Software for modelling dynamic microbial inactivation.

PubMed

Garre, Alberto; Fernández, Pablo S; Lindqvist, Roland; Egea, Jose A

2017-03-01

This contribution presents the bioinactivation software, which implements functions for the modelling of isothermal and non-isothermal microbial inactivation. This software offers features such as user-friendliness, modelling of dynamic conditions, possibility to choose the fitting algorithm and generation of prediction intervals. The software is offered in two different formats: Bioinactivation core and Bioinactivation SE. Bioinactivation core is a package for the R programming language, which includes features for the generation of predictions and for the fitting of models to inactivation experiments using non-linear regression or a Markov Chain Monte Carlo algorithm (MCMC). The calculations are based on inactivation models common in academia and industry (Bigelow, Peleg, Mafart and Geeraerd). Bioinactivation SE supplies a user-friendly interface to selected functions of Bioinactivation core, namely the model fitting of non-isothermal experiments and the generation of prediction intervals. The capabilities of bioinactivation are presented in this paper through a case study, modelling the non-isothermal inactivation of Bacillus sporothermodurans. This study has provided a full characterization of the response of the bacteria to dynamic temperature conditions, including confidence intervals for the model parameters and a prediction interval of the survivor curve. We conclude that the MCMC algorithm produces a better characterization of the biological uncertainty and variability than non-linear regression. The bioinactivation software can be relevant to the food and pharmaceutical industry, as well as to regulatory agencies, as part of a (quantitative) microbial risk assessment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Species and Scale Dependence of Bacterial Motion Dynamics

NASA Astrophysics Data System (ADS)

Sund, N. L.; Yang, X.; Parashar, R.; Plymale, A.; Hu, D.; Kelly, R.; Scheibe, T. D.

2017-12-01

Many metal reducing bacteria are motile with their motion characteristics described by run-and-tumble behavior exhibiting series of flights (jumps) and waiting (residence) time spanning a wide range of values. Accurate models of motility allow for improved design and evaluation of in-situ bioremediation in the subsurface. While many bioremediation models neglect the motion of the bacteria, others treat motility using an advection dispersion equation, which assumes that the motion of the bacteria is Brownian.The assumption of Brownian motion to describe motility has enormous implications on predictive capabilities of bioremediation models, yet experimental evidence of this assumption is mixed [1][2][3]. We hypothesize that this is due to the species and scale dependence of the motion dynamics. We test our hypothesis by analyzing videos of motile bacteria of five different species in open domains. Trajectories of individual cells ranging from several seconds to few minutes in duration are extracted in neutral conditions (in the absence of any chemical gradient). The density of the bacteria is kept low so that the interaction between the bacteria is minimal. Preliminary results show a transition from Fickian (Brownian) to non-Fickian behavior for one species of bacteria (Pelosinus) and persistent Fickian behavior of another species (Geobacter).Figure: Video frames of motile bacteria with the last 10 seconds of their trajectories drawn in red. (left) Pelosinus and (right) Geobacter.[1] Ariel, Gil, et al. "Swarming bacteria migrate by Lévy Walk." Nature Communications 6 (2015).[2] Saragosti, Jonathan, Pascal Silberzan, and Axel Buguin. "Modeling E. coli tumbles by rotational diffusion. Implications for chemotaxis." PloS one 7.4 (2012): e35412.[3] Wu, Mingming, et al. "Collective bacterial dynamics revealed using a three-dimensional population-scale defocused particle tracking technique." Applied and Environmental Microbiology 72.7 (2006): 4987-4994.

Patient satisfaction with extended-interval warfarin monitoring.

PubMed

Carris, Nicholas W; Hwang, Andrew Y; Smith, Steven M; Taylor, James R; Sando, Karen; Powell, Jason; Rosenberg, Eric I; Zumberg, Marc S; Gums, John G; Dietrich, Eric A; Anderson, Katherine Vogel

2016-11-01

Extended-interval monitoring of warfarin has been proposed to reduce follow-up burden and improve patient satisfaction. We aimed to make an initial assessment of anticoagulation satisfaction before and after an extended-interval warfarin monitoring intervention. We conducted a translational prospective single-arm pilot study of extended-interval warfarin monitoring in five pharmacist-managed anticoagulation clinics. Patients meeting CHEST guideline criteria for extended-interval warfarin monitoring began progressive extended-interval follow-up (6, 8, and 12 weeks thereafter). The Duke Anticoagulation Satisfaction Scale (DASS) was administered at baseline and at end-of-study or study removal (in patients no longer appropriate for extended interval follow-up). Forty-six patients had evaluable pre- and post-intervention DASS survey data. Mean age of patients was 66.5 years, 74 % were non-Hispanic whites, and 48 % were men. Patients completed a mean ± SD of 34 ± 22 weeks of follow-up. Mean ± SD total DASS score at baseline was 45.2 ± 14.2 versus 49.1 ± 14.9 at end-of-study (mean change, +3.9 [95 % CI -0.6-8.4; p = 0.09]), indicating no benefit-and trending toward decrement-to anticoagulation satisfaction. Change in anticoagulation satisfaction varied substantially following extended-interval monitoring, with no evidence of improved satisfaction. Plausible reasons for patients not preferring extended-interval monitoring include increased anxiety and disengagement from self-management activities, both potentially related to less frequent feedback and reassurance during extended interval-monitoring. Additional research is needed to identify who is likely to benefit most from extended-interval monitoring. Anticoagulation satisfaction should be considered with clinical factors and shared-decision making when implementing extended-interval warfarin monitoring.

Musical training generalises across modalities and reveals efficient and adaptive mechanisms for reproducing temporal intervals.

PubMed

Aagten-Murphy, David; Cappagli, Giulia; Burr, David

2014-03-01

Expert musicians are able to time their actions accurately and consistently during a musical performance. We investigated how musical expertise influences the ability to reproduce auditory intervals and how this generalises across different techniques and sensory modalities. We first compared various reproduction strategies and interval length, to examine the effects in general and to optimise experimental conditions for testing the effect of music, and found that the effects were robust and consistent across different paradigms. Focussing on a 'ready-set-go' paradigm subjects reproduced time intervals drawn from distributions varying in total length (176, 352 or 704 ms) or in the number of discrete intervals within the total length (3, 5, 11 or 21 discrete intervals). Overall, Musicians performed more veridical than Non-Musicians, and all subjects reproduced auditory-defined intervals more accurately than visually-defined intervals. However, Non-Musicians, particularly with visual stimuli, consistently exhibited a substantial and systematic regression towards the mean interval. When subjects judged intervals from distributions of longer total length they tended to regress more towards the mean, while the ability to discriminate between discrete intervals within the distribution had little influence on subject error. These results are consistent with a Bayesian model that minimizes reproduction errors by incorporating a central tendency prior weighted by the subject's own temporal precision relative to the current distribution of intervals. Finally a strong correlation was observed between all durations of formal musical training and total reproduction errors in both modalities (accounting for 30% of the variance). Taken together these results demonstrate that formal musical training improves temporal reproduction, and that this improvement transfers from audition to vision. They further demonstrate the flexibility of sensorimotor mechanisms in adapting to different task conditions to minimise temporal estimation errors. © 2013.

Modified Confidence Intervals for the Mean of an Autoregressive Process.

DTIC Science & Technology

1985-08-01

Validity of the method 45 3.6 Theorem 47 4 Derivation of corrections 48 Introduction 48 The zero order pivot 50 4.1 Algorithm 50 CONTENTS The first...of standard confidence intervals. There are several standard methods of setting confidence intervals in simulations, including the regener- ative... method , batch means, and time series methods . We-will focus-s on improved confidence intervals for the mean of an autoregressive process, and as such our

[Clinical analysis for patients with continuous ambulatory peritoneal dialysis associated peritonitis].

PubMed

Liu, Jian; Huang, Xun; Liu, Yao; Xu, Hui; Gong, Rui'e; Li, Chunhui

2016-12-28

To analyze the clinical characteristics of continuous ambulatory peritoneal dialysis (CAPD) associated peritonitis in the tertiary hospitals and to discuss the preventive and therapeutic strategy.
 Methods: The clinical characteristics, pathogens, resistance and outcomes of 126 CAPD associated peritonitis in 104 patients from Jan, 2013 to June, 2016, were retrospectively analyzed.
 Results: Among the patients, the incidence rates of abdominal pain, fever, diarrhea and emesis were 104 (82.54%), 56 (44.44%), 49 (38.89%), and 31 (23.60%), respectively. Among them, 88 patients suffered peritonitis once, other 16 patients suffered multiple peritonitis or recurrent peritonitis for 38 times. Among the 38 times, the numbers for recurrent, repeated or catheter-associated peritonitis were 2, 2, or 3, respectively. Peritoneal fluids from 103 cases were cultured, and 64 cases were positive in bacteria, with a rate of 62.14%. A total of 70 strains of bacteria were separated, including 42 strains of gram-positive bacteria, 21 strains of gram-negative bacteria, and 7 strains of fungus. The most common gram-positive pathogens were Staphylococcus epidermidis, Enterococcus faecalis and Staphylococcus haemolyticus, while Escherichia coli, Klebsiella pneumoniae and Klebsiella pneumoniae were the most common gram-negative bacteria. Candida albicans was the major fungal pathogens. Gram-positive cocci showed resistance to gentamycin, levofloxacin, moxifloxacin, vancomycin and linezolid, with a rate at 20.00%, 36.11%, 5%, 0%, and 0%, respectively. The gram-negative bacilli were resistent to cefoperazone/sulbactam, gentamycin, cephazolin, and ceftazidime, with a rate at 6.25%, 10.53%, 64.29%, and 15.38%, respectively. There were no imipenem, amikacin, piperacillin/tazobactam-resistant strains were found.
 Conclusion: The most common pathogen causing CAPD associated peritonitis is gram-positive bacteria. It is crucial to take the anti-infection therapy for CAPD associated peritonitis early. The positive rates for bacterial culture need to be enhanced through improvement of methods. At the same time, doctors could improve the outcome of CAPD associated peritonitis by adjusting the medication according to the drug sensitivity results.

Diode laser for endodontic treatment: investigations of light distribution and disinfection efficiency

NASA Astrophysics Data System (ADS)

Stock, Karl; Graser, Rainer; Udart, Martin; Kienle, Alwin; Hibst, Raimund

2011-03-01

Diode lasers are used in dentistry mainly for oral surgery and disinfection of root canals in endodontic treatment. The purpose of this study was to investigate and to improve the laser induced bacteria inactivation in endodontic treatment. An essential prerequisite of the optimization of the irradiation process and device is the knowledge about the determinative factors of bacteria killing: light intensity? light dosis? temperature? In order to find out whether high power NIR laser bacterial killing is caused by a photochemical or a photothermal process we heated bacteria suspensions of E. coli K12 by a water bath and by a diode laser (940 nm) with the same temporal temperature course. Furthermore, bacteria suspensions were irradiated while the temperature was fixed by ice water. Killing of bacteria was measured via fluorescence labeling. In order to optimize the irradiation of the root canal, we designed special fiber tips with radial light emission characteristic by optical ray tracing simulations. Also, we calculated the resulting light distribution in dentin by voxelbased Monte Carlo simulations. Furthermore, we irradiated root canals of extracted human teeth using different fiber tip geometries and measured the resulting light and heat distribution by CCD-camera and thermography. Comparison of killing rates between laser and water based heating shows no significant differences, and irradiation of ice cooled suspensions has no substantial killing effect. Thus, the most important parameter for bacterial killing is the maximum temperature. Irradiation of root canals using fiber tips with radial light emission results in a more defined irradiated area with minor irradiation of the apex and higher intensity and therefore higher temperature increase on root canal surface. In conclusion, our experiments show that at least for E. coli bacteria inactivation by NIR laser irradiation is solely based on a thermal process and that heat distribution in root canal can be significantly improved by specially designed fiber tips.

Resolving colocalization of bacteria and metal(loid)s on plant root surfaces by combining fluorescence in situ hybridization (FISH) with multiple-energy micro-focused X-ray fluorescence (ME μXRF).

PubMed

Honeker, Linnea K; Root, Robert A; Chorover, Jon; Maier, Raina M

2016-12-01

Metal(loid)-contamination of the environment due to anthropogenic activities is a global problem. Understanding the fate of contaminants requires elucidation of biotic and abiotic factors that influence metal(loid) speciation from molecular to field scales. Improved methods are needed to assess micro-scale processes, such as those occurring at biogeochemical interfaces between plant tissues, microbial cells, and metal(loid)s. Here we present an advanced method that combines fluorescence in situ hybridization (FISH) with synchrotron-based multiple-energy micro-focused X-ray fluorescence microprobe imaging (ME μXRF) to examine colocalization of bacteria and metal(loid)s on root surfaces of plants used to phytostabilize metalliferous mine tailings. Bacteria were visualized on a small root section using SytoBC nucleic acid stain and FISH probes targeting the domain Bacteria and a specific group (Alphaproteobacteria, Gammaproteobacteria, or Actinobacteria). The same root region was then analyzed for elemental distribution and metal(loid) speciation of As and Fe using ME μXRF. The FISH and ME μXRF images were aligned using ImageJ software to correlate microbiological and geochemical results. Results from quantitative analysis of colocalization show a significantly higher fraction of As colocalized with Fe-oxide plaques on the root surfaces (fraction of overlap 0.49±0.19) than to bacteria (0.072±0.052) (p<0.05). Of the bacteria that colocalized with metal(loid)s, Actinobacteria, known for their metal tolerance, had a higher correlation with both As and Fe than Alphaproteobacteria or Gammaproteobacteria. This method demonstrates how coupling these micro-techniques can expand our understanding of micro-scale interactions between roots, metal(loid)s and microbes, information that should lead to improved mechanistic models of metal(loid) speciation and fate. Copyright © 2016 Elsevier B.V. All rights reserved.

High-intensity interval training for improving postprandial hyperglycemia.

PubMed

Little, Jonathan P; Francois, Monique E

2014-12-01

High-intensity interval training (HIIT) has garnered attention in recent years as a time-efficient exercise option for improving cardiovascular and metabolic health. New research demonstrates that HIIT may be particularly effective for improving postprandial hyperglycemia in individuals with, or at risk for, type 2 diabetes (T2D). These findings have clinical relevance because elevated postprandial hyperglycemia is a significant risk factor for cardiovascular morbidity and mortality. This article summarizes the latest evidence demonstrating that HIIT can improve postprandial glucose control to highlight the potential application of HIIT in the prevention and management of T2D and associated cardiovascular complications.

Stroke preparedness in children: translating knowledge into behavioral intent: a systematic review and meta-analysis.

PubMed

Ottawa, Cassandra; Sposato, Luciano A; Nabbouh, Fadl; Saposnik, Gustavo

2015-10-01

If translated into behavioral intent, improving stroke knowledge may potentially impact on better outcomes. Children are an attractive target population since they can drive familial behavioral changes. However, the impact of interventions on stroke knowledge among children is unclear. We performed a systematic review and meta-analysis to investigate whether educational interventions targeting children improve stroke knowledge and lead to behavioral changes. We searched Ovid, PubMed, and Embase between January 2000 and December 2014. We included studies written in English reporting the number of children aged 6-15 years undergoing educational interventions on stroke and providing the results for baseline and early and late postintervention tests. We compared the proportion of correct answers between baseline, early, and late responses for two endpoints: knowledge and behavioral intent. Of the initial 58 articles found, we included nine that met the inclusion criteria. Compared with baseline tests (51·7%, 95% confidence interval 40·9-62·4), there was improvement in stroke knowledge in early (74·0%, 95% confidence interval 64·4-82·5, P = 0·002) and late (67·3%, 95% confidence interval 55·4-78·2, P = 0·027) responses. There was improvement in the early (92·1%, 95% confidence interval 86·0-96·6, P < 0·001) and late (83·9%, 95% confidence interval 73·5-92·1, P = 0·001) responses for behavioral intent compared with the baseline assessment (63·8%, 95% confidence interval 53·5-73·4). Children are a potentially attractive target population for improvement in stroke knowledge and behavioral intent, both in the short and long term. Our findings may support the implementation of large-scale stroke educational initiatives targeting children. © 2015 World Stroke Organization.

[III Catalan registry of ST elevation acute myocardial infarction. Comparison with former Catalan registries I and II from Catalonia, Spain].

PubMed

Figueras, Jaume; Heras, Magda; Baigorri, Francisco; Elosua, Roberto; Ferreira, Ignacio; Santaló, Miquel

2009-11-14

To analyze the use of reperfusion therapy in patients with ST elevation myocardial infarction (STEMI) in Catalonia in a registry performed in 2006 (IAM CAT III) and its comparison with 2 previous registries Frequency of reperfusion therapy and time intervals between symptom onset - reperfusion therapy were the principal variables investigated. The IAM CAT I (June-December 2000) included 1,450 patients, the IAM CAT II (October 2002-April 2003) 1,386, and the IAM CAT III (October-December 2006) 367. The proportion of patients treated with reperfusion increased progressively (72%, 79% and 81%) as the use of primary angioplasty (5%, 10% and 33%). In the III registry the transfer system most frequently used was the SEM/061 (17%, 32% and 47%, respectively) but the time interval symptom onset-first contact with the medical system did not improve (II, 90 vs III, 105 min), the interval symptom onset-thrombolytic therapy did hardly change (178, 165 and 177 min) and the interval hospital arrival-trombolysis (needle-door) tended to improve (59, 42 and 42 min). Thirty day mortality in STEMI patients declined progressively through the 3 registries (12.1, 10.6 and 7.4%, p=0.012). The proportion of STEMI patients treated with reperfusion has improved but the interval to its application has not been shortened. To improve the latter it is mandatory an earlier contact with the medical system, a shortening of the intervals door-needle and door-balloon through better coordination between the 061, the sanitary personnel and the hospital administration, and to consider the subject as a real sanitary priority.

Optimal debulking targets in women with advanced stage ovarian cancer: a retrospective study of immediate versus interval debulking surgery.

PubMed

Altman, Alon D; Nelson, Gregg; Chu, Pamela; Nation, Jill; Ghatage, Prafull

2012-06-01

The objective of this study was to examine both overall and disease-free survival of patients with advanced stage ovarian cancer after immediate or interval debulking surgery based on residual disease. We performed a retrospective chart review at the Tom Baker Cancer Centre in Calgary, Alberta of patients with pathologically confirmed stage III or IV ovarian cancer, fallopian tube cancer, or primary peritoneal cancer between 2003 and 2007. We collected data on the dates of diagnosis, recurrence, and death; cancer stage and grade, patients' age, surgery performed, and residual disease. One hundred ninety-two patients were included in the final analysis. The optimal debulking rate with immediate surgery was 64.8%, and with interval surgery it was 85.9%. There were improved overall and disease-free survival rates for optimally debulked disease (< 1 cm) with both immediate and interval surgery (P < 0.001) compared to suboptimally debulked disease. Overall survival rates for optimally debulked disease were not significantly different in patients having immediate and interval surgery (P = 0.25). In the immediate surgery group, patients with microscopic residual disease had better disease-free survival (P = 0.015) and overall survival (P = 0.005) than patients with < 1 cm residual disease. In patients who had interval surgery, those who had microscopic residual disease had more improved disease-free survival than those with < 1 cm disease (P = 0.05), but they did not have more improved overall survival (P = 0.42). Patients with microscopic residual disease who had immediate surgery had a significantly better overall survival rate than those who had interval surgery (P = 0.034). In women with advanced stage ovarian cancer, the goal of surgery should be resection of disease to microscopic residual at the initial procedure. This results in improved overall survival than lesser degrees of resection. Further studies are required to determine optimal surgical management.

Improved assay for quantitating adherence of ruminal bacteria to cellulose.

PubMed Central

Rasmussen, M A; White, B A; Hespell, R B

1989-01-01

A quantitative technique suitable for the determination of adherence of ruminal bacteria to cellulose was developed. This technique employs adherence of cells to cellulose disks and alleviates the problem of nonspecific cell entrapment within cellulose particles. By using this technique, it was demonstrated that the adherence of Ruminococcus flavefaciens FD1 to cellulose was inhibited by formaldehyde, methylcellulose, and carboxymethyl cellulose. Adherence was unaffected by acid hydrolysates of methylcellulose, glucose, and cellobiose. PMID:2782879

Method of detecting and counting bacteria

NASA Technical Reports Server (NTRS)

Picciolo, G. L.; Chappelle, E. W. (Inventor)

1976-01-01

An improved method is provided for determining bacterial levels, especially in samples of aqueous physiological fluids. The method depends on the quantitative determination of bacterial adenosine triphosphate (ATP) in the presence of nonbacterial ATP. The bacterial ATP is released by cell rupture and is measured by an enzymatic bioluminescent assay. A concentration technique is included to make the method more sensitive. It is particularly useful where the fluid to be measured contains an unknown or low bacteria count.

Development of principles of two-cascaded laser speckle-microscopy with implication to high-precision express diagnostics of chlamydial infection

NASA Astrophysics Data System (ADS)

Ulianova, Onega; Moiseeva, Yulia; Filonova, Nadezhda; Subbotina, Irina; Zaitsev, Sergey; Saltykov, Yury; Polyanina, Tatiana; Lyapina, Anna; Ulyanov, Sergey; Larionova, Olga; Utz, Sergey; Feodorova, Valentina

2018-04-01

Principles of two-cascaded laser speckle-microscopy prospect for application to express diagnostics of chlamydial infection are developed. Prototype of two-cascaded speckle-microscope is designed and tested. Specific case of illumination of bacterial cells by dynamic speckles is considered. Express method of detection of epithelial cells, containing defects, which are caused by Chlamydia trachomatis bacteria, is suggested. Results of improved recognition of C. trachomatis bacteria are discussed.

Impedimetric detection of bacteria by using a microfluidic chip and silver nanoparticle based signal enhancement.

PubMed

Wang, Renjie; Xu, Yi; Sors, Thomas; Irudayaraj, Joseph; Ren, Wen; Wang, Rong

2018-02-19

The authors describe a method that can significantly improve the performance of impedimetric detection of bacteria. A multifunctional microfluidic chip was designed consisting of interdigitated microelectrodes and a micro-mixing zone with a Tesla structure. This maximizes the coating of bacterial surfaces with nanoparticles and results in improved impedimetric detection. The method was applied to the detection of Escherichia coli O157:H7 (E. coli). Silver enhancement was accomplished by coating E.coli with the cationic polymer diallyldimethylammonium chloride (PDDA) to form positively charged E. coli/PDDA complexes. Then, gold nanoparticles (AuNPs) were added, and the resulting E. coli/PDDA/AuNPs complexes were collected at interdigitated electrodes via positive dielectrophoresis (pDEP). A silver adduct was then formed on the E. coli/PDDA/AuNP complexes by using silver enhancement solutions and by using the AuNPs as catalysts. The combination of pDEP based capture and of using silver adducts reduces impedance by increasing the conductivity of the solution and the double layer capacitance around the microelectrodes. Impedance decreases linearly in the 2 × 10 3 -2 × 10 5  cfu·mL -1 E. coli concentration range, with a 500 cfu·mL -1 detection limit. Egg shell wash samples and tap water spiked with E. coli were successfully used for validation, and this demonstrates the practical application of this method. Graphical abstract Schematic representation of the AuNP@Ag enhancement method integrated with multifunctional microfluidic chip platform for impedimetric quantitation of bacteria. The method significantly improves the performance of impedimetric detection of bacteria.

Fibrolytic Bacteria Isolated from the Rumen of North American Moose (Alces alces) and Their Use as a Probiotic in Neonatal Lambs

PubMed Central

Ishaq, Suzanne L.; Kim, Christina J.; Reis, Doug; Wright, André-Denis G.

2015-01-01

Fibrolytic bacteria were isolated from the rumen of North American moose (Alces alces), which eat a high-fiber diet of woody browse. It was hypothesized that fibrolytic bacteria isolated from the moose rumen could be used as probiotics to improve fiber degradation and animal production. Thirty-one isolates (Bacillus, n = 26; Paenibacillus, n = 1; and Staphylococcus, n = 4) were cultured from moose rumen digesta samples collected in Vermont. Using Sanger sequencing of the 16S rRNA gene, culturing techniques, and optical densities, isolates were identified and screened for biochemical properties important to plant carbohydrate degradation. Five isolates were selected as candidates for use as a probiotic, which was administered daily to neonate lambs for 9 weeks. It was hypothesized that regular administration of a probiotic to improve fibrolysis to neonate animals through weaning would increase the developing rumen bacterial diversity, increase animal production, and allow for long-term colonization of the probiotic species. Neither weight gain nor wool quality was improved in lambs given a probiotic, however, dietary efficiency was increased as evidenced by the reduced feed intake (and rearing costs) without a loss to weight gain. Experimental lambs had a lower acetate to propionate ratio than control lambs, which was previously shown to indicate increased dietary efficiency. Fibrolytic bacteria made up the majority of sequences, mainly Prevotella, Butyrivibrio, and Ruminococcus. While protozoal densities increased over time and were stable, methanogen densities varied greatly in the first six months of life for lambs. This is likely due to the changing diet and bacterial populations in the developing rumen. PMID:26716685

Fibrolytic Bacteria Isolated from the Rumen of North American Moose (Alces alces) and Their Use as a Probiotic in Neonatal Lambs.

PubMed

Ishaq, Suzanne L; Kim, Christina J; Reis, Doug; Wright, André-Denis G

2015-01-01

Fibrolytic bacteria were isolated from the rumen of North American moose (Alces alces), which eat a high-fiber diet of woody browse. It was hypothesized that fibrolytic bacteria isolated from the moose rumen could be used as probiotics to improve fiber degradation and animal production. Thirty-one isolates (Bacillus, n = 26; Paenibacillus, n = 1; and Staphylococcus, n = 4) were cultured from moose rumen digesta samples collected in Vermont. Using Sanger sequencing of the 16S rRNA gene, culturing techniques, and optical densities, isolates were identified and screened for biochemical properties important to plant carbohydrate degradation. Five isolates were selected as candidates for use as a probiotic, which was administered daily to neonate lambs for 9 weeks. It was hypothesized that regular administration of a probiotic to improve fibrolysis to neonate animals through weaning would increase the developing rumen bacterial diversity, increase animal production, and allow for long-term colonization of the probiotic species. Neither weight gain nor wool quality was improved in lambs given a probiotic, however, dietary efficiency was increased as evidenced by the reduced feed intake (and rearing costs) without a loss to weight gain. Experimental lambs had a lower acetate to propionate ratio than control lambs, which was previously shown to indicate increased dietary efficiency. Fibrolytic bacteria made up the majority of sequences, mainly Prevotella, Butyrivibrio, and Ruminococcus. While protozoal densities increased over time and were stable, methanogen densities varied greatly in the first six months of life for lambs. This is likely due to the changing diet and bacterial populations in the developing rumen.

Use of bacteria for improving the lignocellulose biorefinery process: importance of pre-erosion.

PubMed

Zhuo, Shengnan; Yan, Xu; Liu, Dan; Si, Mengying; Zhang, Kejing; Liu, Mingren; Peng, Bing; Shi, Yan

2018-01-01

Biological pretreatment is an important alternative strategy for biorefining lignocellulose and has attracted increasing attention in recent years. However, current designs for this pretreatment mainly focus on using various white rot fungi, overlooking the bacteria. To the best of our knowledge, for the first time, we evaluated the potential contribution of bacteria to lignocellulose pretreatment, with and without a physicochemical process, based on the bacterial strain Pandoraea sp. B-6 (hereafter B-6) that was isolated from erosive bamboo slips. Moreover, the mechanism of the improvement of reducing sugar yield by bacteria was elucidated via analyses of the physicochemical changes of corn stover (CS) before and after pretreatment. The digestibility of CS pretreated with B-6 was equivalent to that of untreated CS. The recalcitrant CS surface provided fewer mediators for contact with the extracellular enzymes of B-6. A pre-erosion strategy using a tetrahydrofuran-water co-solvent system was shown to destroy the recalcitrant CS surface. The optimal condition for pre-erosion showed a 6.5-fold increase in enzymatic digestibility compared with untreated CS. The pre-erosion of CS can expose more phenolic compounds that were chelated to oxidized Mn 3+ and also provided mediators for combination with laccase, which was attributable to B-6 pretreatment. B-6 pretreatment following pre-erosion exhibited a sugar yield that was 91.2 mg/g greater than that of pre-erosion alone and 7.5-fold higher than that of untreated CS. This pre-erosion application was able to destroy the recalcitrant CS surface, thus leading to a rough and porous architecture that better facilitated the diffusion and transport of lignin derivatives. This enhanced the ability of laccase and manganese peroxidase secreted by B-6 to improve the efficiency of this biological pretreatment. Bacteria were not found useful alone as a biological pretreatment, but they significantly improved enzymatic digestion after lignocellulose breakdown via other physicochemical methods. Nonetheless, phenyl or phenoxy radicals were used by laccase and manganese peroxidase in B-6 for lignin attack or lignin depolymerization. These particular mediators released from the recalcitrance network of lignocellulose openings are important for the efficacy of this bacterial pretreatment. Our findings thus offer a novel perspective on the effective design of biological pretreatment methods for lignocellulose.

The Interaction between Plants and Bacteria in the Remediation of Petroleum Hydrocarbons: An Environmental Perspective

PubMed Central

Gkorezis, Panagiotis; Daghio, Matteo; Franzetti, Andrea; Van Hamme, Jonathan D.; Sillen, Wouter; Vangronsveld, Jaco

2016-01-01

Widespread pollution of terrestrial ecosystems with petroleum hydrocarbons (PHCs) has generated a need for remediation and, given that many PHCs are biodegradable, bio- and phyto-remediation are often viable approaches for active and passive remediation. This review focuses on phytoremediation with particular interest on the interactions between and use of plant-associated bacteria to restore PHC polluted sites. Plant-associated bacteria include endophytic, phyllospheric, and rhizospheric bacteria, and cooperation between these bacteria and their host plants allows for greater plant survivability and treatment outcomes in contaminated sites. Bacterially driven PHC bioremediation is attributed to the presence of diverse suites of metabolic genes for aliphatic and aromatic hydrocarbons, along with a broader suite of physiological properties including biosurfactant production, biofilm formation, chemotaxis to hydrocarbons, and flexibility in cell-surface hydrophobicity. In soils impacted by PHC contamination, microbial bioremediation generally relies on the addition of high-energy electron acceptors (e.g., oxygen) and fertilization to supply limiting nutrients (e.g., nitrogen, phosphorous, potassium) in the face of excess PHC carbon. As an alternative, the addition of plants can greatly improve bioremediation rates and outcomes as plants provide microbial habitats, improve soil porosity (thereby increasing mass transfer of substrates and electron acceptors), and exchange limiting nutrients with their microbial counterparts. In return, plant-associated microorganisms improve plant growth by reducing soil toxicity through contaminant removal, producing plant growth promoting metabolites, liberating sequestered plant nutrients from soil, fixing nitrogen, and more generally establishing the foundations of soil nutrient cycling. In a practical and applied sense, the collective action of plants and their associated microorganisms is advantageous for remediation of PHC contaminated soil in terms of overall cost and success rates for in situ implementation in a diversity of environments. Mechanistically, there remain biological unknowns that present challenges for applying bio- and phyto-remediation technologies without having a deep prior understanding of individual target sites. In this review, evidence from traditional and modern omics technologies is discussed to provide a framework for plant–microbe interactions during PHC remediation. The potential for integrating multiple molecular and computational techniques to evaluate linkages between microbial communities, plant communities and ecosystem processes is explored with an eye on improving phytoremediation of PHC contaminated sites. PMID:27917161

The Interaction between Plants and Bacteria in the Remediation of Petroleum Hydrocarbons: An Environmental Perspective.

PubMed

Gkorezis, Panagiotis; Daghio, Matteo; Franzetti, Andrea; Van Hamme, Jonathan D; Sillen, Wouter; Vangronsveld, Jaco

2016-01-01

Widespread pollution of terrestrial ecosystems with petroleum hydrocarbons (PHCs) has generated a need for remediation and, given that many PHCs are biodegradable, bio- and phyto-remediation are often viable approaches for active and passive remediation. This review focuses on phytoremediation with particular interest on the interactions between and use of plant-associated bacteria to restore PHC polluted sites. Plant-associated bacteria include endophytic, phyllospheric, and rhizospheric bacteria, and cooperation between these bacteria and their host plants allows for greater plant survivability and treatment outcomes in contaminated sites. Bacterially driven PHC bioremediation is attributed to the presence of diverse suites of metabolic genes for aliphatic and aromatic hydrocarbons, along with a broader suite of physiological properties including biosurfactant production, biofilm formation, chemotaxis to hydrocarbons, and flexibility in cell-surface hydrophobicity. In soils impacted by PHC contamination, microbial bioremediation generally relies on the addition of high-energy electron acceptors (e.g., oxygen) and fertilization to supply limiting nutrients (e.g., nitrogen, phosphorous, potassium) in the face of excess PHC carbon. As an alternative, the addition of plants can greatly improve bioremediation rates and outcomes as plants provide microbial habitats, improve soil porosity (thereby increasing mass transfer of substrates and electron acceptors), and exchange limiting nutrients with their microbial counterparts. In return, plant-associated microorganisms improve plant growth by reducing soil toxicity through contaminant removal, producing plant growth promoting metabolites, liberating sequestered plant nutrients from soil, fixing nitrogen, and more generally establishing the foundations of soil nutrient cycling. In a practical and applied sense, the collective action of plants and their associated microorganisms is advantageous for remediation of PHC contaminated soil in terms of overall cost and success rates for in situ implementation in a diversity of environments. Mechanistically, there remain biological unknowns that present challenges for applying bio- and phyto-remediation technologies without having a deep prior understanding of individual target sites. In this review, evidence from traditional and modern omics technologies is discussed to provide a framework for plant-microbe interactions during PHC remediation. The potential for integrating multiple molecular and computational techniques to evaluate linkages between microbial communities, plant communities and ecosystem processes is explored with an eye on improving phytoremediation of PHC contaminated sites.

An improved method for identification of small non-coding RNAs in bacteria using support vector machine

NASA Astrophysics Data System (ADS)

Barman, Ranjan Kumar; Mukhopadhyay, Anirban; Das, Santasabuj

2017-04-01

Bacterial small non-coding RNAs (sRNAs) are not translated into proteins, but act as functional RNAs. They are involved in diverse biological processes like virulence, stress response and quorum sensing. Several high-throughput techniques have enabled identification of sRNAs in bacteria, but experimental detection remains a challenge and grossly incomplete for most species. Thus, there is a need to develop computational tools to predict bacterial sRNAs. Here, we propose a computational method to identify sRNAs in bacteria using support vector machine (SVM) classifier. The primary sequence and secondary structure features of experimentally-validated sRNAs of Salmonella Typhimurium LT2 (SLT2) was used to build the optimal SVM model. We found that a tri-nucleotide composition feature of sRNAs achieved an accuracy of 88.35% for SLT2. We validated the SVM model also on the experimentally-detected sRNAs of E. coli and Salmonella Typhi. The proposed model had robustly attained an accuracy of 81.25% and 88.82% for E. coli K-12 and S. Typhi Ty2, respectively. We confirmed that this method significantly improved the identification of sRNAs in bacteria. Furthermore, we used a sliding window-based method and identified sRNAs from complete genomes of SLT2, S. Typhi Ty2 and E. coli K-12 with sensitivities of 89.09%, 83.33% and 67.39%, respectively.

Plant growth and arbuscular mycorrhizae development in oil sands processing by-products.

PubMed

Boldt-Burisch, Katja; Naeth, M Anne; Schneider, Uwe; Schneider, Beate; Hüttl, Reinhard F

2018-04-15

Soil pollutants such as hydrocarbons can induce toxic effects in plants and associated arbuscular mycorrhizal fungi (AMF). This study was conducted to evaluate if the legume Lotus corniculatus and the grass Elymus trachycaulus and arbuscular mycorrhizal fungi could grow in two oil sands processing by-products after bitumen extraction from the oil sands in northern Alberta, Canada. Substrate treatments were coarse tailings sand (CTS), a mix of dry mature fine tailings (MFT) with CTS (1:1) and Pleistocene sandy soil (hydrocarbon free); microbial treatments were without AMF, with AMF and AMF plus soil bacteria isolated from oil sands reclamation sites. Plant biomass, root morphology, leaf water content, shoot tissue phosphorus content and mycorrhizal colonization were evaluated. Both plant species had reduced growth in CTS and tailings mix relative to sandy soil. AMF frequency and intensity in roots of E. trachycaulus was not influenced by soil hydrocarbons; however, it decreased significantly over time in roots of L. corniculatus without bacteria in CTS. Mycorrhizal inoculation alone did not significantly improve plant growth in CTS and tailings mix; however, inoculation with mycorrhizae plus bacteria led to a significantly positive response of both plant species in CTS. Thus, combined inoculation with selected mycorrhizae and bacteria led to synergistic effects. Such combinations may be used in future to improve plant growth in reclamation of CTS and tailings mix. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of microorganisms in concrete: a promising sustainable strategy to improve concrete durability.

PubMed

Wang, Jianyun; Ersan, Yusuf Cagatay; Boon, Nico; De Belie, Nele

2016-04-01

The beneficial effect of microbially induced carbonate precipitation on building materials has been gradually disclosed in the last decade. After the first applications of on historical stones, promising results were obtained with the respect of improved durability. An extensive study then followed on the application of this environmentally friendly and compatible material on a currently widely used construction material, concrete. This review is focused on the discussion of the impact of the two main applications, bacterial surface treatment and bacteria based crack repair, on concrete durability. Special attention was paid to the choice of suitable bacteria and the metabolic pathway aiming at their functionality in concrete environment. Interactions between bacterial cells and cementitious matrix were also elaborated. Furthermore, recommendations to improve the effectiveness of bacterial treatment are provided. Limitations of current studies, updated applications and future application perspectives are shortly outlined.

pH-Taxis of Biohybrid Microsystems

NASA Astrophysics Data System (ADS)

Zhuang, Jiang; Wright Carlsen, Rika; Sitti, Metin

2015-06-01

The last decade has seen an increasing number of studies developing bacteria and other cell-integrated biohybrid microsystems. However, the highly stochastic motion of these microsystems severely limits their potential use. Here, we present a method that exploits the pH sensing of flagellated bacteria to realize robust drift control of multi-bacteria propelled microrobots. Under three specifically configured pH gradients, we demonstrate that the microrobots exhibit both unidirectional and bidirectional pH-tactic behaviors, which are also observed in free-swimming bacteria. From trajectory analysis, we find that the swimming direction and speed biases are two major factors that contribute to their tactic drift motion. The motion analysis of microrobots also sheds light on the propulsion dynamics of the flagellated bacteria as bioactuators. It is expected that similar driving mechanisms are shared among pH-taxis, chemotaxis, and thermotaxis. By identifying the mechanism that drives the tactic behavior of bacteria-propelled microsystems, this study opens up an avenue towards improving the control of biohybrid microsystems. Furthermore, assuming that it is possible to tune the preferred pH of bioactuators by genetic engineering, these biohybrid microsystems could potentially be applied to sense the pH gradient induced by cancerous cells in stagnant fluids inside human body and realize targeted drug delivery.

Enhancement of algicidal properties of immobilized Bacillus methylotrophicus ZJU by coating with magnetic Fe₃O₄ nanoparticles and wheat bran.

PubMed

Sun, Pengfei; Hui, Cai; Wang, Sheng; Khan, Rashid Azim; Zhang, Qichun; Zhao, Yu-Hua

2016-01-15

Algicidal bacteria offer a promising option for killing cyanobacteria. In this study, a newly isolated strain of Bacillus methylotrophicus, ZJU, was used to control Microcystis aeruginosa. Analyses of relative reactive oxygen level, malondialdehyde content, superoxide dismutase activity, and fluorescence staining indicated that oxidative damage caused by the algicidal supernatant of strain ZJU mainly affected the cell membrane and consequently the membrane permeability and membrane potential of M. aeruginosa cells. Furthermore, an embedded immobilization technique was employed to improve the practical application of strain ZJU as an algicidal agent. On this basis, we proposed a novel concept of enhancing the algicidal properties of immobilized ZJU by adding Fe3O4 nanoparticles and wheat bran in the process of immobilization. Our studies showed that Fe3O4 nanoparticles conferred the immobilized bacteria with a magnetization of 30.87 emu/g, and this magnetization enabled efficient re-collection of the immobilized bacteria by magnetic means. Moreover, wheat bran endowed the immobilized bacteria with 10.34% higher algicidal activity than immobilized bacteria without wheat bran. The results indicate a novel concept of enhancing the algicidal property of bacteria against M. aeruginosa by adding Fe3O4 nanoparticles and wheat bran. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of DNA extraction kits and modification of DNA elution procedure for the quantitation of subdominant bacteria from piggery effluents with real-time PCR

PubMed Central

Desneux, Jérémy; Pourcher, Anne-Marie

2014-01-01

Four commercial DNA extraction kits and a minor modification in the DNA elution procedure were evaluated for the quantitation of bacteria in pig manure samples. The PowerSoil®, PowerFecal®, NucleoSpin® Soil kits and QIAamp® DNA Stool Mini kit were tested on raw manure samples and on lagoon effluents for their ability to quantify total bacteria and a subdominant bacteria specific of pig manure contamination: Lactobacillus amylovorus. The NucleoSpin® Soil kit (NS kit), and to a lesser extent the PowerFecal® kit were the most efficient methods. Regardless of the kit utilized, the modified elution procedure increased DNA yield in the lagoon effluent by a factor of 1.4 to 1.8. When tested on 10 piggery effluent samples, compared to the QIAamp kit, the NS kit combined with the modified elution step, increased by a factor up to 1.7 log10 the values of the concentration of L. amylovorus. Regardless of the type of manure, the best DNA quality and the highest concentrations of bacteria were obtained using the NS kit combined with the modification of the elution procedure. The method recommended here significantly improved quantitation of subdominant bacteria in manure. PMID:24838631

What bacteria are living in my food? An open-ended practical series involving identification of unknown foodborne bacteria using molecular techniques.

PubMed

Prasad, Prascilla; Turner, Mark S

2011-01-01

This open-ended practical series titled "Molecular Identification of Unknown Food Bacteria" which extended over a 6-week period was designed with the aims of giving students an opportunity to gain an understanding of naturally occurring food bacteria and skills in contemporary molecular methods using real food samples. The students first isolated two unknown bacterial strains from two food sources from which they extracted DNA and performed PCR targeting the 16S rRNA gene. Gel electrophoresis was used to analyze both genomic DNA preparations and PCR products. Following purification of PCR products, DNA sequencing was carried out and sequence trace quality was analyzed. The students successfully identified the two unknown bacteria using the BLAST search engine and a wide variety of different organisms were found. Assessment of their understanding of the procedure and ability to explain their findings using supporting primary research literature was via an individually prepared written report. Feedback from students over 2 years (n = 52) in a questionnaire revealed that the practical series was an engaging learning experience and lead to perceived improvements in knowledge of molecular techniques and bioinformatics and also about commonly occurring bacteria in foods. Copyright © 2011 Wiley Periodicals, Inc.

Bacterial Diversity Analysis during the Fermentation Processing of Traditional Chinese Yellow Rice Wine Revealed by 16S rDNA 454 Pyrosequencing.

PubMed

Fang, Ruo-si; Dong, Ya-chen; Chen, Feng; Chen, Qi-he

2015-10-01

Rice wine is a traditional Chinese fermented alcohol drink. Spontaneous fermentation with the use of the Chinese starter and wheat Qu lead to the growth of various microorganisms during the complete brewing process. It's of great importance to fully understand the composition of bacteria diversity in rice wine in order to improve the quality and solve safety problems. In this study, a more comprehensive bacterial description was shown with the use of bacteria diversity analysis, which enabled us to have a better understanding. Rarefaction, rank abundance, alpha Diversity, beta diversity and principal coordinates analysis simplified their complex bacteria components and provide us theoretical foundation for further investigation. It has been found bacteria diversity is more abundant at mid-term and later stage of brewing process. Bacteria community analysis reveals there is a potential safety hazard existing in the fermentation, since most of the sequence reads are assigned to Enterobacter (7900 at most) and Pantoea (7336 at most), followed by Staphylococcus (2796 at most) and Pseudomonas (1681 at most). Lactic acid bacteria are rare throughout the fermentation process which is not in accordance with other reports. This work may offer us an opportunity to investigate micro ecological fermentation system in food industry. © 2015 Institute of Food Technologists®

Acetic acid bacteria in traditional balsamic vinegar: phenotypic traits relevant for starter cultures selection.

PubMed

Gullo, Maria; Giudici, Paolo

2008-06-30

This review focuses on acetic acid bacteria in traditional balsamic vinegar process. Although several studies are available on acetic acid bacteria ecology, metabolism and nutritional requirements, their activity as well as their technological traits in homemade vinegars as traditional balsamic vinegar is not well known. The basic technology to oxidise cooked grape must to produce traditional balsamic vinegar is performed by the so called "seed-vinegar" that is a microbiologically undefined starter culture obtained from spontaneous acetification of previous raw material. Selected starter cultures are the main technological improvement in order to innovate traditional balsamic vinegar production but until now they are rarely applied. To develop acetic acid bacteria starter cultures, selection criteria have to take in account composition of raw material, acetic acid bacteria metabolic activities, applied technology and desired characteristics of the final product. For traditional balsamic vinegar, significative phenotypical traits of acetic acid bacteria have been highlighted. Basic traits are: ethanol preferred and efficient oxidation, fast rate of acetic acid production, tolerance to high concentration of acetic acid, no overoxidation and low pH resistance. Specific traits are tolerance to high sugar concentration and to a wide temperature range. Gluconacetobacter europaeus and Acetobacter malorum strains can be evaluated to develop selected starter cultures since they show one or more suitable characters.

Bacterial Bolsheviks: PS II and the Evolution of the Oxygenic Revolution

NASA Astrophysics Data System (ADS)

Kopp, R. E.; Kirschvink, J. L.; Newman, D. K.; Nash, C. Z.; Hilburn, I. A.

2003-12-01

After the rise of life itself, the most radical transformation of Earth's biogeochemical cycles was the transition from an anoxic to an oxic world. Though various studies have suggested O2 made its first bulk appearance in the atmosphere some time between 3.8 and 2.1 Ga, virtually all analyses agree the production of large quantities of free O2 was triggered by the evolution of oxygenic photosynthesis. We suggest the oldest strong geological evidence for O2 is the 2.22 Ga Kalahari Mn member of the Hotazel BIF (1), as in the oceans only free O2 can oxidize soluble Mn(II) into insoluble Mn(IV). Some have argued, however, that oxygenic cyanobacteria had originated by 2.7 Ga. The ˜500 Myr "gap" has often been interpreted as the timescale for gradual evolutionary improvement of the O2-generating system. Biochemical and genomic analyses of photosynthetic bacteria indicate that photosystems I and II, which operate together in cyanobacteria, had a long history of parallel development. Green sulfur bacteria and heliobacteria use PS-II, while green non-sulfur and purple bacteria use PS-I; none can use H2O as an electron donor. Recent genetic analyses show lateral gene transfer was rampant among photosynthetic lineages (2). Moreover, extant cyanobacteria shut down PS-II in the presence of an alternative electron donor like H2S. This suggests PS-I and PS-II came together with their functions intact. Hence, most `debugging' of the two systems predates their merger in the ancestor of modern cyanobacteria. The time interval between the lateral transfer events and the evolution of oxygenic photosynthesis could thus have been geologically short. We suggest the ˜500 Myr "gap" may result from misinterpretations. The presence of oxygenic photosynthesis is uncertain before the deposition of the Hotazel formation, in the aftermath of the Makganyene glaciation (1). A simple model of nutrient and reductant fluxes argues that, once triggered, the oxygenation of a reducing surface environment warmed by a CH4 greenhouse (3) should occur fairly rapidly, within ˜ 10 My. The trigger requires both the evolution of cyanobacteria and sufficiently high nutrient (mainly P) fluxes to allow O2 production to overwhelm reductant fluxes. P flux into the oceans in glaciated worlds correlates with increased continental weathering during glacial intervals (4). Thus, were cyanobacteria present during the Huronian glaciations, which predate 2.22 Ga (5), these glaciations should have triggered the oxygenation event. Instead, the oxygenation event seems to correlate with the Makganyene glaciation, at 2.22 Ga (6). The appearance of red beds in the Upper Timeball Hill formation directly underlying the Makganyene diamictite supports this interpretation. As would be expected from a glaciation associated with the destruction of a CH4 greenhouse, paleomagnetic data indicate the Makganyene glaciation was a global Snowball event (7). Cyanobacteria appear to have evolved in the short interval between the Huronian glaciations and the Makganyene glaciation. The lengthy delay between the earliest life on Earth and the appearance of cyanobacteria suggests that the oxygenic revolution was a fairly low probability event; planets with oxygenic biospheres may be quite rare. 1. J. L. Kirschvink et al., PNAS 97, 1400-1405 (2000). 2. J. Raymond et al., Science 298, 1616-1620 (2002). 3. A. A. Pavlov et al., JGR 105, 11981-11990 (2000). 4. K. B. F”llmi, Geology 23, 503-506 (1995). 5. S. R. Noble, P. C. Lightfoot, Can. J. Earth Sci. 29, 1424-1429 (1992). 6. D. H. Cornell et al., Precamb. Res. 79, 101-123 (1996). 7. D. A. Evans et al., Nature 386, 262-266 (1997).

The Role of Soil Microorganisms in Plant Mineral Nutrition—Current Knowledge and Future Directions

PubMed Central

Jacoby, Richard; Peukert, Manuela; Succurro, Antonella; Koprivova, Anna; Kopriva, Stanislav

2017-01-01

In their natural environment, plants are part of a rich ecosystem including numerous and diverse microorganisms in the soil. It has been long recognized that some of these microbes, such as mycorrhizal fungi or nitrogen fixing symbiotic bacteria, play important roles in plant performance by improving mineral nutrition. However, the full range of microbes associated with plants and their potential to replace synthetic agricultural inputs has only recently started to be uncovered. In the last few years, a great progress has been made in the knowledge on composition of rhizospheric microbiomes and their dynamics. There is clear evidence that plants shape microbiome structures, most probably by root exudates, and also that bacteria have developed various adaptations to thrive in the rhizospheric niche. The mechanisms of these interactions and the processes driving the alterations in microbiomes are, however, largely unknown. In this review, we focus on the interaction of plants and root associated bacteria enhancing plant mineral nutrition, summarizing the current knowledge in several research fields that can converge to improve our understanding of the molecular mechanisms underpinning this phenomenon. PMID:28974956

Pyruvate cycle increases aminoglycoside efficacy and provides respiratory energy in bacteria.

PubMed

Su, Yu-Bin; Peng, Bo; Li, Hui; Cheng, Zhi-Xue; Zhang, Tian-Tuo; Zhu, Jia-Xin; Li, Dan; Li, Min-Yi; Ye, Jin-Zhou; Du, Chao-Chao; Zhang, Song; Zhao, Xian-Liang; Yang, Man-Jun; Peng, Xuan-Xian

2018-02-13

The emergence and ongoing spread of multidrug-resistant bacteria puts humans and other species at risk for potentially lethal infections. Thus, novel antibiotics or alternative approaches are needed to target drug-resistant bacteria, and metabolic modulation has been documented to improve antibiotic efficacy, but the relevant metabolic mechanisms require more studies. Here, we show that glutamate potentiates aminoglycoside antibiotics, resulting in improved elimination of antibiotic-resistant pathogens. When exploring the metabolic flux of glutamate, it was found that the enzymes that link the phosphoenolpyruvate (PEP)-pyruvate-AcCoA pathway to the TCA cycle were key players in this increased efficacy. Together, the PEP-pyruvate-AcCoA pathway and TCA cycle can be considered the pyruvate cycle (P cycle). Our results show that inhibition or gene depletion of the enzymes in the P cycle shut down the TCA cycle even in the presence of excess carbon sources, and that the P cycle operates routinely as a general mechanism for energy production and regulation in Escherichia coli and Edwardsiella tarda These findings address metabolic mechanisms of metabolite-induced potentiation and fundamental questions about bacterial biochemistry and energy metabolism.

A role for IL-22 in the relationship between intestinal helminths, gut microbiota and mucosal immunity

PubMed Central

Leung, Jacqueline M.; Loke, P’ng

2014-01-01

The intestinal tract is home to nematodes as well as commensal bacteria (microbiota), which have coevolved with the mammalian host. The mucosal immune system must balance between an appropriate response to dangerous pathogens and an inappropriate response to commensal microbiota that may breach the epithelial barrier, in order to maintain intestinal homeostasis. IL-22 has been shown to play a critical role in maintaining barrier homeostasis against intestinal pathogens and commensal bacteria. Here we review the advances in our understanding of the role of IL-22 in helminth infections, as well as in response to commensal and pathogenic bacteria of the intestinal tract. We then consider the relationship between intestinal helminths and gut microbiota and hypothesize that this relationship may explain how helminths may improve symptoms of inflammatory bowel diseases. We propose that by inducing an immune response that includes IL-22, intestinal helminths may enhance the mucosal barrier function of the intestinal epithelium. This may restore the mucosal microbiota populations from dysbiosis associated with colitis and improve intestinal homeostasis. PMID:23178750

Understanding and Modulating Mammalian-Microbial Communication for Improved Human Health

PubMed Central

Mani, Sridhar; Boelsterli, Urs A.; Redinbo, Matthew R.

2013-01-01

The fact that the bacteria in the human gastrointestinal (GI) tract play a symbiotic role was noted as early as 1885, well before we began to manage microbial infections using antibiotics. However, even with the first antimicrobial compounds used in humans, the sulfa drugs, microbes were recognized to be critically involved in the biotransformation of these therapeutics. Thus, the roles played by the microbiota in physiology and in the management of human health have long been appreciated. Detailed examinations of GI symbiotic bacteria that started in the early 2000s and the first phases of the Human Microbiome Project that were completed in 2012 have ushered in an exciting period of granularity with respect to the ecology, genetics, and chemistry of the mammalian-microbial axes of communication. Here we review aspects of the biochemical pathways at play between commensal GI bacteria and several mammalian systems, including both local-epithelia and nonlocal responses including inflammation, immunology, metabolism, and neurobiology. Finally, we discuss how the microbial biotransformation of therapeutic compounds, such as anticancer or nonsteroidal anti-inflammatory drugs, can be modulated to reduce toxicity and potentially improve therapeutic efficacy. PMID:24160697

Phyto-synthesis and antibacterial studies of bio-based silver nanoparticles using Sesbania grandiflora (Avisa) leaf tea extract

NASA Astrophysics Data System (ADS)

Mallikarjuna, K.; Balasubramanyam, K.; Narasimha, G.; Kim, Haekyoung

2018-01-01

Green nanobiotechnology using plants, micro-organisms, and their extracts has improved the utilization of natural resources. More efficient and eco-friendly routes are being developed for the creation of benign, biodegradable materials that have medical applicability. We developed silver nanoparticles encapsulated with Sesbania grandiflora (Avisa) leaf extract, which served as a reducing and capping material. The structure and functionalization of the synthesized nanoparticles were investigated using UV-vis, XRD, FE-TEM, SAED, and FTIR analyses. The nanoparticles were found to be isotropic and spherical, with a core of Ag wrapped in phytochemicals. The presence of phytochemicals stabilized the nanoparticles during production by preventing agglomeration. Antibacterial properties against both gram-positive and gram-negative bacteria were also tested. The phytochemical-wrapped silver nanoparticles were more effective antibiotics than were bare silver nanoparticles. The phytochemicals were likely responsible for both direct and indirect improvements in the bactericidal properties of the Ag particles. Additionally, the developed nanoparticles showed higher antibacterial activity towards gram-negative bacteria than towards gram-positive bacteria, with the cell wall playing an important role in adsorption and absorption of Ag+.

Short-chain fatty acids production and microbial community in sludge alkaline fermentation: Long-term effect of temperature.

PubMed

Yuan, Yue; Liu, Ye; Li, Baikun; Wang, Bo; Wang, Shuying; Peng, Yongzhen

2016-07-01

Sludge alkaline fermentation has been reported to achieve efficient short-chain fatty acids (SCFAs) production. Temperature played important role in further improved SCFAs production. Long-term SCFAs production from sludge alkaline fermentation was compared between mesotherm (30±2°C) and microtherm (15±2°C). The study of 90days showed that mesotherm led to 2.2-folds production of SCFAs as microtherm and enhanced the production of acetic acid as major component of SCFAs. Soluble protein and carbohydrate at mesotherm was 2.63-folds as that at microtherm due to higher activities of protease and α-glucosidase, guaranteeing efficient substrates to produce SCFAs. Illumina MiSeq sequencing revealed that microtherm increased the abundance of Corynebacterium, Alkaliflexus, Pseudomonas and Guggenheimella, capable of enhancing hydrolysis. Hydrolytic bacteria, i.e. Alcaligenes, Anaerolinea and Ottowia, were enriched at mesotherm. Meanwhile, acidogenic bacteria showed higher abundance at mesotherm than microtherm. Therefore, enrichment of functional bacteria and higher microbial activities resulted in the improved SCFAs at mesotherm. Copyright © 2016 Elsevier Ltd. All rights reserved.

Native Phytoremediation Potential of Urtica dioica for Removal of PCBs and Heavy Metals Can Be Improved by Genetic Manipulations Using Constitutive CaMV 35S Promoter.

PubMed

Viktorova, Jitka; Jandova, Zuzana; Madlenakova, Michaela; Prouzova, Petra; Bartunek, Vilem; Vrchotova, Blanka; Lovecka, Petra; Musilova, Lucie; Macek, Tomas

2016-01-01

Although stinging nettle (Urtica dioica) has been shown to reduce HM (heavy metal) content in soil, its wider phytoremediation potential has been neglected. Urtica dioica was cultivated in soils contaminated with HMs or polychlorinated biphenyls (PCBs). After four months, up to 33% of the less chlorinated biphenyls and 8% of HMs (Zn, Pb, Cd) had been removed. Bacteria were isolated from the plant tissue, with the endophytic bacteria Bacillus shackletonii and Streptomyces badius shown to have the most significant effect. These bacteria demonstrated not only benefits for plant growth, but also extreme tolerance to As, Zn and Pb. Despite these results, the native phytoremediation potential of nettles could be improved by biotechnologies. Transient expression was used to investigate the functionality of the most common constitutive promoter, CaMV 35S in Urtica dioica. This showed the expression of the CUP and bphC transgenes. Collectively, our findings suggest that remediation by stinging nettle could have a much wider range of applications than previously thought.

Native Phytoremediation Potential of Urtica dioica for Removal of PCBs and Heavy Metals Can Be Improved by Genetic Manipulations Using Constitutive CaMV 35S Promoter

PubMed Central

Viktorova, Jitka; Jandova, Zuzana; Madlenakova, Michaela; Prouzova, Petra; Bartunek, Vilem; Vrchotova, Blanka; Lovecka, Petra; Musilova, Lucie; Macek, Tomas

2016-01-01

Although stinging nettle (Urtica dioica) has been shown to reduce HM (heavy metal) content in soil, its wider phytoremediation potential has been neglected. Urtica dioica was cultivated in soils contaminated with HMs or polychlorinated biphenyls (PCBs). After four months, up to 33% of the less chlorinated biphenyls and 8% of HMs (Zn, Pb, Cd) had been removed. Bacteria were isolated from the plant tissue, with the endophytic bacteria Bacillus shackletonii and Streptomyces badius shown to have the most significant effect. These bacteria demonstrated not only benefits for plant growth, but also extreme tolerance to As, Zn and Pb. Despite these results, the native phytoremediation potential of nettles could be improved by biotechnologies. Transient expression was used to investigate the functionality of the most common constitutive promoter, CaMV 35S in Urtica dioica. This showed the expression of the CUP and bphC transgenes. Collectively, our findings suggest that remediation by stinging nettle could have a much wider range of applications than previously thought. PMID:27930707

Modeling seasonal variability of fecal coliform in natural surface waters using the modified SWAT

NASA Astrophysics Data System (ADS)

Cho, Kyung Hwa; Pachepsky, Yakov A.; Kim, Minjeong; Pyo, JongCheol; Park, Mi-Hyun; Kim, Young Mo; Kim, Jung-Woo; Kim, Joon Ha

2016-04-01

Fecal coliforms are indicators of pathogens and thereby, understanding of their fate and transport in surface waters is important to protect drinking water sources and public health. We compiled fecal coliform observations from four different sites in the USA and Korea and found a seasonal variability with a significant connection to temperature levels. In all observations, fecal coliform concentrations were relatively higher in summer and lower during the winter season. This could be explained by the seasonal dominance of growth or die-off of bacteria in soil and in-stream. Existing hydrologic models, however, have limitations in simulating the seasonal variability of fecal coliform. Soil and in-stream bacterial modules of the Soil and Water Assessment Tool (SWAT) model are oversimplified in that they exclude simulations of alternating bacterial growth. This study develops a new bacteria subroutine for the SWAT in an attempt to improve its prediction accuracy. We introduced critical temperatures as a parameter to simulate the onset of bacterial growth/die-off and to reproduce the seasonal variability of bacteria. The module developed in this study will improve modeling for environmental management schemes.

Application of bacteria from non-cultivated plants to promote growth, alter root architecture and alleviate salt stress of cotton.

PubMed

Irizarry, I; White, J F

2017-04-01

Cotton seeds are frequently treated with acid to remove fibres and reduce seed-transmitted diseases. This process also eliminates beneficial bacteria on the seed surface. The goal of this research was to seek and apply beneficial bacteria to acid delinted cotton seeds to evaluate their growth-promoting and salt stress alleviating effects in seedlings. Bacteria were isolated from non-cultivated plants in the Malvaceae. Seeds were collected from Portia tree (Thespesia populnea) and wild cotton (Gossypium hirsutum) from coastal and arid areas of Puerto Rico. Bacillus amyloliquefaciens, Curtobacterium oceanosedimentum and Pseudomonas oryzihabitans were inoculated onto acid delinted cotton seeds. Bacteria increased cotton seed germination and length of emerging seedling radicles. Cotton seeds were inoculated with B. amyloliquefaciens to evaluate growth and root architecture of non-stressed and salt stressed seedlings. Inoculating cotton seeds with B. amyloliquefaciens led to a greater percentage of seedlings with expanded cotyledons after 8 days, enhanced primary and lateral root growth, and altered root architecture. Similar results were obtained when okra seeds were inoculated with B. amyloliquefaciens. The data supported the hypothesis that non-cultivated plants in the Malvaceae growing in stressful environments possess bacteria that promote growth, alter root architecture and alleviate salt stress of cotton and okra seedlings. This study demonstrated the effects of applying beneficial bacteria on acid delinted cotton seeds. Inoculating seeds with salt stress alleviating bacteria could improve the growth of crop seedlings that are vulnerable to soil salinization. © 2017 The Society for Applied Microbiology.

The fecal bacteria

USGS Publications Warehouse

Sadowsky, Michael J.; Whitman, Richard L.

2011-01-01

The Fecal Bacteria offers a balanced, integrated discussion of fecal bacteria and their presence and ecology in the intestinal tract of mammals, in the environment, and in the food supply. This volume covers their use in examining and assessing water quality in order to offer protection from illnesses related to swimming in or ingesting contaminated water, in addition to discussing their use in engineering considerations of water quality, modeling, monitoring, and regulations. Fecal bacteria are additionally used as indicators of contamination of ready-to-eat foods and fresh produce. The intestinal environment, the microbial community structure of the gut microbiota, and the physiology and genomics of this broad group of microorganisms are explored in the book. With contributions from an internationally recognized group of experts, the book integrates medicine, public health, environmental, and microbiological topics in order to provide a unique, holistic understanding of fecal bacteria. Moreover, it shows how the latest basic science and applied research findings are helping to solve problems and develop effective management strategies. For example, readers will discover how the latest tools and molecular approaches have led to our current understanding of fecal bacteria and enabled us to improve human health and water quality. The Fecal Bacteria is recommended for microbiologists, clinicians, animal scientists, engineers, environmental scientists, food safety experts, water quality managers, and students. It will help them better understand fecal bacteria and use their knowledge to protect human and environmental health. They can also apply many of the techniques and molecular tools discussed in this book to the study of a broad range of microorganisms in a variety of habitats.

Microbial community dynamics and effect of environmental microbial reservoirs on red-backed salamanders (Plethodon cinereus)

PubMed Central

Loudon, Andrew H; Woodhams, Douglas C; Parfrey, Laura Wegener; Archer, Holly; Knight, Rob; McKenzie, Valerie; Harris, Reid N

2014-01-01

Beneficial cutaneous bacteria on amphibians can protect against the lethal disease chytridiomycosis, which has devastated many amphibian species and is caused by the fungus Batrachochytrium dendrobatidis. We describe the diversity of bacteria on red-backed salamanders (Plethodon cinereus) in the wild and the stability of these communities through time in captivity using culture-independent Illumina 16S rRNA gene sequencing. After field sampling, salamanders were housed with soil from the field or sterile media. The captive conditions led to different trajectories of bacterial communities. Eight OTUs present on >90% of salamanders in the field, through time, and in both treatments were defined as the core community, suggesting that some bacteria are closely associated with the host and are independent of an environmental reservoir. One of these taxa, a Pseudomonas sp., was previously cultured from amphibians and found to be antifungal. As all host-associated bacteria were found in the soil reservoir, environmental microbes strongly influence host–microbial diversity and likely regulate the core community. Using PICRUSt, an exploratory bioinformatics tool to predict gene functions, we found that core skin bacteria provided similar gene functions to the entire community. We suggest that future experiments focus on testing whether core bacteria on salamander skin contribute to the observed resistance to chytridiomycosis in this species even under hygenic captive conditions. For disease-susceptible hosts, providing an environmental reservoir with defensive bacteria in captive-rearing programs may improve outcomes by increasing bacterial diversity on threatened amphibians or increasing the likelihood that defensive bacteria are available for colonization. PMID:24335825

The First Report of Drug Resistant Bacteria Isolated from the Brown-Banded Cockroach, Supella longipalpa, in Ahvaz, South-western Iran

PubMed Central

Vazirianzadeh, Babak; Dehghani, Rouhullah; Mehdinejad, Manijeh; Sharififard, Mona; Nasirabadi, Nersi

2014-01-01

Background The brown-banded cockroach, Supella longipalpa is known as a carrier of pathogenic bacteria in urban environments, but its role is not well documented regarding the carriage of antibiotic-resistant pathogenic bacteria in Iran. The aim of this study was to determine the resistance bacteria isolated from the brown-banded cockroach in Ahvaz, south west of Iran. Methods: Totally 39 cockroaches were collected from kitchen area of houses and identified. All specimens were cultured to isolate the bacterial agents on blood agar and MacConky agar media. The microorganisms were identified using necessary differential and biochemical tests. Antimicrobial susceptibility tests were performed for isolated organisms by Kirby-Bauer’s disk diffusion according to NCLI guideline, using 18 antibiotics. Results: From the 39 collected S. langipalpa, 179 bacterial agents were isolated, 92 of alimentary ducts and 87 of external body surfaces. Isolated bacteria from cockroaches were identified as Enterobacter spp., Klebsiella spp., Citrobacter spp., Escherichia coli, Salmonella spp., Proteus spp., coagulase negative staphylococci, Serratia marcescens, Staphylococcus aureus, and Bacillus species. The pattern resistance rates were determined for gram negative bacilli and gram positive cocci regarding 18 antibiotics. Conclusion: The brown-banded cockroach can be involved in the spread of drug resistant bacteria and increases the possibility of contacting human environment to drug resistant bacteria. Therefore, the potential of removing this insect should be improved. This is the first original report of drug resistant bacteria isolated from the brown-banded cockroach of Iran. PMID:25629065

Bioretention column study of bacteria community response to salt-enriched artificial stormwater.

PubMed

Endreny, Theodore; Burke, David J; Burchhardt, Kathleen M; Fabian, Mark W; Kretzer, Annette M

2012-01-01

Cold climate cities with green infrastructure depend on soil bacteria to remove nutrients from road salt-enriched stormwater. Our research examined how bacterial communities in laboratory columns containing bioretention media responded to varying concentrations of salt exposure from artificial stormwater and the effect of bacteria and salt on column effluent concentrations. We used a factorial design with two bacteria treatments (sterile, nonsterile) and three salt concentrations (935, 315, and 80 ppm), including a deionized water control. Columns were repeatedly saturated with stormwater or deionized and then drained throughout 5 wk, with the last week of effluent analyzed for water chemistry. To examine bacterial communities, we extracted DNA from column bioretention media at time 0 and at week 5 and used molecular profiling techniques to examine bacterial community changes. We found that bacterial community taxa changed between time 0 and week 5 and that there was significant separation between taxa among salt treatments. Bacteria evenness was significantly affected by stormwater treatment, but there were no differences in bacterial richness or diversity. Soil bacteria and salt treatments had a significant effect on the effluent concentration of NO, PO, Cu, Pb, and Zn based on ANOVA tests. The presence of bacteria reduced effluent NO and Zn concentrations by as much as 150 and 25%, respectively, while having a mixed effect on effluent PO concentrations. Our results demonstrate how stormwater can affect bacterial communities and how the presence of soil bacteria improves pollutant removal by green infrastructure. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Short-term low-intensity blood flow restricted interval training improves both aerobic fitness and muscle strength.

PubMed

de Oliveira, M F M; Caputo, F; Corvino, R B; Denadai, B S

2016-09-01

The present study aimed to analyze and compare the effects of four different interval-training protocols on aerobic fitness and muscle strength. Thirty-seven subjects (23.8 ± 4 years; 171.7 ± 9.5 cm; 70 ± 11 kg) were assigned to one of four groups: low-intensity interval training with (BFR, n = 10) or without (LOW, n = 7) blood flow restriction, high-intensity interval training (HIT, n = 10), and combined HIT and BFR (BFR + HIT, n = 10, every session performed 50% as BFR and 50% as HIT). Before and after 4 weeks training (3 days a week), the maximal oxygen uptake (VO2max ), maximal power output (Pmax ), onset blood lactate accumulation (OBLA), and muscle strength were measured for all subjects. All training groups were able to improve OBLA (BFR, 16%; HIT, 25%; HIT + BFR, 22%; LOW, 6%), with no difference between groups. However, VO2max and Pmax improved only for BFR (6%, 12%), HIT (9%, 15%) and HIT + BFR (6%, 11%), with no difference between groups. Muscle strength gains were only observed after BFR training (11%). This study demonstrates the advantage of short-term low-intensity interval BFR training as the single mode of training able to simultaneously improve aerobic fitness and muscular strength. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Improved tracking and resolution of bacteria in holographic microscopy using dye and fluorescent protein labeling

NASA Astrophysics Data System (ADS)

Nadeau, Jay; Cho, YongBin; Kühn, Jonas; Liewer, Kurt

2016-04-01

Digital holographic microscopy (DHM) is an emerging imaging technique that permits instantaneous capture of a relatively large sample volume. However, large volumes usually come at the expense of lower spatial resolution, and the technique has rarely been used with prokaryotic cells due to their small size and low contrast. In this paper we demonstrate the use of a Mach-Zehnder dual-beam instrument for imaging of labeled and unlabeled bacteria and microalgae. Spatial resolution of 0.3 micrometers is achieved, providing a sampling of several pixels across a typical prokaryotic cell. Both cellular motility and morphology are readily recorded. The use of dyes provides both amplitude and phase contrast improvement and is of use to identify cells in dense samples.

Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis

PubMed Central

Adegbola, Richard A.; DeAntonio, Rodrigo; Hill, Philip C.; Roca, Anna; Usuf, Effua; Hoet, Bernard; Greenwood, Brian M.

2014-01-01

Background Infection with Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide, especially in low income countries where pneumococcal conjugate vaccines (PCVs) are still underused. In countries where PCVs have been introduced, much of their efficacy has resulted from their impact on nasopharyngeal carriage in vaccinated children. Understanding the epidemiology of carriage for S. pneumoniae and other common respiratory bacteria in developing countries is crucial for implementing appropriate vaccination strategies and evaluating their impact. Methods and Findings We have systematically reviewed published studies reporting nasopharyngeal or oropharyngeal carriage of S. pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Neisseria meningitidis in children and adults in low and lower-middle income countries. Studies reporting pneumococcal carriage for healthy children <5 years of age were selected for a meta-analysis. The prevalences of carriage for S. pneumoniae, H. influenzae, and M. catarrhalis were generally higher in low income than in lower-middle income countries and were higher in young children than in adults. The prevalence of S. aureus was high in neonates. Meta-analysis of data from young children before the introduction of PCVs showed a pooled prevalence estimate of 64.8% (95% confidence interval, 49.8%–76.1%) in low income countries and 47.8% (95% confidence interval, 44.7%–50.8%) in lower-middle income countries. The most frequent serotypes were 6A, 6B, 19A, 19F, and 23F. Conclusions In low and lower-middle income countries, pneumococcal carriage is frequent, especially in children, and the spectrum of serotypes is wide. However, because data are limited, additional studies are needed to adequately assess the impact of PCV introduction on carriage of respiratory bacteria in these countries. PMID:25084351

Diagnosing periprosthetic infection: false-positive intraoperative Gram stains.

PubMed

Oethinger, Margret; Warner, Debra K; Schindler, Susan A; Kobayashi, Hideo; Bauer, Thomas W

2011-04-01

Intraoperative Gram stains have a reported low sensitivity but high specificity when used to help diagnose periprosthetic infections. In early 2008, we recognized an unexpectedly high frequency of apparent false-positive Gram stains from revision arthroplasties. The purpose of this report is to describe the cause of these false-positive test results. We calculated the sensitivity and specificity of all intraoperative Gram stains submitted from revision arthroplasty cases during a 3-month interval using microbiologic cultures of the same samples as the gold standard. Methods of specimen harvesting, handling, transport, distribution, specimen processing including tissue grinding/macerating, Gram staining, and interpretation were studied. After a test modification, results of specimens were prospectively collected for a second 3-month interval, and the sensitivity and specificity of intraoperative Gram stains were calculated. The retrospective review of 269 Gram stains submitted from revision arthroplasties indicated historic sensitivity and specificity values of 23% and 92%, respectively. Systematic analysis of all steps of the procedure identified Gram-stained but nonviable bacteria in commercial broth reagents used as diluents for maceration of periprosthetic membranes before Gram staining and culture. Polymerase chain reaction and sequencing showed mixed bacterial DNA. Evaluation of 390 specimens after initiating standardized Millipore filtering of diluent fluid revealed a reduced number of positive Gram stains, yielding 9% sensitivity and 99% specificity. Clusters of false-positive Gram stains have been reported in other clinical conditions. They are apparently rare related to diagnosing periprosthetic infections but have severe consequences if used to guide treatment. Even occasional false-positive Gram stains should prompt review of laboratory methods. Our observations implicate dead bacteria in microbiologic reagents as potential sources of false-positive Gram stains.

Bacterial Diversity and Mycotoxin Reduction During Maize Fermentation (Steeping) for Ogi Production

PubMed Central

Okeke, Chiamaka A.; Ezekiel, Chibundu N.; Nwangburuka, Cyril C.; Sulyok, Michael; Ezeamagu, Cajethan O.; Adeleke, Rasheed A.; Dike, Stanley K.; Krska, Rudolf

2015-01-01

Bacterial diversity and community structure of two maize varieties (white and yellow) during fermentation/steeping for ogi production, and the influence of spontaneous fermentation on mycotoxin reduction in the gruel were studied. A total of 142 bacterial isolates obtained at 24–96 h intervals were preliminarily identified by conventional microbiological methods while 60 selected isolates were clustered into 39 OTUs consisting of 15 species, 10 genera, and 3 phyla by 16S rRNA sequence analysis. Lactic acid bacteria constituted about 63% of all isolated bacteria and the genus Pediococcus dominated (white maize = 84.8%; yellow maize = 74.4%). Pediococcus acidilactici and Lactobacillus paraplantarum were found at all steeping intervals of white and yellow maize, respectively, while P. claussenii was present only at the climax stage of steeping white maize. In both maize varieties, P. pentosaceus was found at 24–72 h. Mycotoxin concentrations (μg/kg) in the unsteeped grains were: white maize (aflatoxin B1 = 0.60; citrinin = 85.8; cyclopiazonic acid = 23.5; fumonisins (B1/B2/B3) = 68.4–483; zearalenone = 3.3) and yellow maize (aflatoxins (B1/B2/M1) = 22.7–513; citrinin = 16,800; cyclopiazonic acid = 247; fumonisins (B1/B2/B3) = 252–1,586; zearalenone = 205). Mycotoxins in both maize varieties were significantly (p < 0.05) reduced across steeping periods. This study reports for the first time: (a) the association of L. paraplantarum, P. acidilactici, and P. claussenii with ogi production from maize, (b) citrinin occurrence in Nigerian maize and ogi, and (c) aflatoxin M1, citrinin and cyclopiazonic acid degradation/loss due to fermentation in traditional cereal-based fermented food. PMID:26697001

Microbial Contamination of Human Milk Purchased Via the Internet

PubMed Central

Hogan, Joseph S.; McNamara, Kelly A.; Gudimetla, Vishnu; Dillon, Chelsea E.; Kwiek, Jesse J.; Geraghty, Sheela R.

2013-01-01

OBJECTIVE: To quantify microbial contamination of human milk purchased via the Internet as an indicator of disease risk to recipient infants. METHODS: Cross-sectional sample of human milk purchased via a popular US milk-sharing Web site (2012). Individuals advertising milk were contacted to arrange purchase, and milk was shipped to a rented mailbox in Ohio. The Internet milk samples (n = 101) were compared with unpasteurized samples of milk donated to a milk bank (n = 20). RESULTS: Most (74%) Internet milk samples were colonized with Gram-negative bacteria or had >104 colony-forming units/mL total aerobic count. They exhibited higher mean total aerobic, total Gram-negative, coliform, and Staphylococcus sp counts than milk bank samples. Growth of most species was positively associated with days in transit (total aerobic count [log10 colony-forming units/mL] β = 0.71 [95% confidence interval: 0.38–1.05]), and negatively associated with number of months since the milk was expressed (β = −0.36 [95% confidence interval: −0.55 to −0.16]), per simple linear regression. No samples were HIV type 1 RNA-positive; 21% of Internet samples were cytomegalovirus DNA-positive. CONCLUSIONS: Human milk purchased via the Internet exhibited high overall bacterial growth and frequent contamination with pathogenic bacteria, reflecting poor collection, storage, or shipping practices. Infants consuming this milk are at risk for negative outcomes, particularly if born preterm or are medically compromised. Increased use of lactation support services may begin to address the milk supply gap for women who want to feed their child human milk but cannot meet his or her needs. PMID:24144714

Dissolved organic nitrogen (DON) profile during backwashing cycle of drinking water biofiltration.

PubMed

Liu, Bing; Gu, Li; Yu, Xin; Yu, Guozhong; Zhang, Huining; Xu, Jinli

2012-01-01

A comprehensive investigation was made in this study on the variation of dissolved organic nitrogen (DON) during a whole backwashing cycle of the biofiltration for drinking water treatment. In such a cycle, the normalized DON concentration (C(effluent)/C(influent)) was decreased from 0.98 to 0.90 in the first 1.5h, and then gradually increased to about 1.5 in the following 8h. Finally, it remained stable until the end of this 24-hour cycle. This clearly 3-stage profile of DON could be explained by three aspects as follows: (1) the impact of the backwashing on the biomass and the microbial activity; (2) the release of soluble microbial products (SMPs) during the biofiltration; (3) the competition between heterotrophic bacteria and nitrifying bacteria. All the facts supported that more DON was generated during later part of the backwashing cycle. The significance of the conclusion is that the shorter backwashing intervals between backwashing for the drinking water biofilter should further decrease the DON concentration in effluent of biofilter. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Predicting Bacteria Removal by Enhanced Stormwater Control Measures (SCMs) at the Watershed Scale

NASA Astrophysics Data System (ADS)

Wolfand, J.; Bell, C. D.; Boehm, A. B.; Hogue, T. S.; Luthy, R. G.

2017-12-01

Urban stormwater is a major cause of water quality impairment, resulting in surface waters that fail to meet water quality standards and support their designated uses. Fecal indicator bacteria are present in high concentrations in stormwater and are strictly regulated in receiving waters; yet, their fate and transport in urban stormwater is poorly understood. Stormwater control measures (SCMs) are often used to treat, infiltrate, and release urban runoff, but field measurements show that the removal of bacteria by these structural solutions is limited (median log removal = 0.24, n = 370). Researchers have therefore looked to improve bacterial removal by enhancing SCMs through alterations in flow regimes or adding geomedia such as biochar. The present research seeks to develop a model to predict removal of fecal indicator bacteria by enhanced SCMs at the watershed scale in a semi-arid climate. Using the highly developed Ballona Creek watershed (290 km2) located in Los Angeles County as a case study, a hydrologic model is coupled with a stochastic water quality model to predict E. coli concentration near the outfall of the Ballona Creek, Santa Monica Bay. A hydrologic model was developed using EPA SWMM, calibrated for flow from water year 1998-2006 (NSE = 0.94; R2 = 0.94), and validated from water year 2007-2015 (NSE = 0.90; R2 = 0.93). This bacterial loading model was then linked to EPA SUSTAIN and a SCM bacterial removal script to simulate log removal of bacteria by various SCMs and predict bacterial concentrations in Ballona Creek. Preliminary results suggest small enhancements to SCMs that improve bacterial removal (<0.5 log removal) may offer large benefits to surface water quality and enable communities such as Los Angeles to meet their regulatory requirements.

Improved oil recovery using bacteria isolated from North Sea petroleum reservoirs

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

Davey, R.A.; Lappin-Scott, H.

1995-12-31

During secondary oil recovery, water is injected into the formation to sweep out the residual oil. The injected water, however, follows the path of least resistance through the high-permeability zones, leaving oil in the low-permeability zones. Selective plugging of these their zones would divert the waterflood to the residual oil and thus increase the life of the well. Bacteria have been suggested as an alternative plugging agent to the current method of polymer injection. Starved bacteria can penetrate deeply into rock formations where they attach to the rock surfaces, and given the right nutrients can grow and produce exo-polymer, reducingmore » the permeability of these zones. The application of microbial enhanced oil recovery has only been applied to shallow, cool, onshore fields to date. This study has focused on the ability of bacteria to enhance oil recovery offshore in the North Sea, where the environment can be considered extreme. A screen of produced water from oil reservoirs (and other extreme subterranean environments) was undertaken, and two bacteria were chosen for further work. These two isolates were able to grow and survive in the presence of saline formation waters at a range of temperatures above 50{degrees}C as facultative anaerobes. When a solution of isolates was passed through sandpacks and nutrients were added, significant reductions in permeabilities were achieved. This was confirmed in Clashach sandstone at 255 bar, when a reduction of 88% in permeability was obtained. Both isolates can survive nutrient starvation, which may improve penetration through the reservoir. Thus, the isolates show potential for field trials in the North Sea as plugging agents.« less

Fast transfer of crossmodal time interval training.

PubMed

Chen, Lihan; Zhou, Xiaolin

2014-06-01

Sub-second time perception is essential for many important sensory and perceptual tasks including speech perception, motion perception, motor coordination, and crossmodal interaction. This study investigates to what extent the ability to discriminate sub-second time intervals acquired in one sensory modality can be transferred to another modality. To this end, we used perceptual classification of visual Ternus display (Ternus in Psychol Forsch 7:81-136, 1926) to implicitly measure participants' interval perception in pre- and posttests and implemented an intra- or crossmodal sub-second interval discrimination training protocol in between the tests. The Ternus display elicited either an "element motion" or a "group motion" percept, depending on the inter-stimulus interval between the two visual frames. The training protocol required participants to explicitly compare the interval length between a pair of visual, auditory, or tactile stimuli with a standard interval or to implicitly perceive the length of visual, auditory, or tactile intervals by completing a non-temporal task (discrimination of auditory pitch or tactile intensity). Results showed that after fast explicit training of interval discrimination (about 15 min), participants improved their ability to categorize the visual apparent motion in Ternus displays, although the training benefits were mild for visual timing training. However, the benefits were absent for implicit interval training protocols. This finding suggests that the timing ability in one modality can be rapidly acquired and used to improve timing-related performance in another modality and that there may exist a central clock for sub-second temporal processing, although modality-specific perceptual properties may constrain the functioning of this clock.

A case of hyperammonemia with obstructive urinary tract infection by urease-producing bacteria.

PubMed

Goda, Toshiaki; Watanabe, Kotaro; Kobayashi, Junya; Nagai, Yasuharu; Ohara, Nobuyuki; Takahashi, Daisuke

2017-03-28

A 79-year-old woman was admitted emergently for disturbance of consciousness. Her consciousness level was Japan coma scale 20, and she presented with hypermyotonia. Brain magnetic resonance imaging and cerebrospinal fluid examination showed normal findings. Her blood tests showed an increased ammonia level of 291 μg/dl with normal liver function. We catheterized the bladder for urinary retention. Eight hours after admission, the blood level of ammonia decreased to 57 μg/dl and the patient's consciousness level improved. Corynebacterium pseudodiphtheriticum, which is a bacteria producing urease, was detected from a urine culture. It is important to recognize that obstructive urinary tract infection caused by urease-producing bacteria can cause hyperammonemia.

Sub-Optimal Treatment of Bacterial Biofilms

PubMed Central

Song, Tianyan; Duperthuy, Marylise; Wai, Sun Nyunt

2016-01-01

Bacterial biofilm is an emerging clinical problem recognized in the treatment of infectious diseases within the last two decades. The appearance of microbial biofilm in clinical settings is steadily increasing due to several reasons including the increased use of quality of life-improving artificial devices. In contrast to infections caused by planktonic bacteria that respond relatively well to standard antibiotic therapy, biofilm-forming bacteria tend to cause chronic infections whereby infections persist despite seemingly adequate antibiotic therapy. This review briefly describes the responses of biofilm matrix components and biofilm-associated bacteria towards sub-lethal concentrations of antimicrobial agents, which may include the generation of genetic and phenotypic variabilities. Clinical implications of bacterial biofilms in relation to antibiotic treatments are also discussed. PMID:27338489

Development of bioconcrete material using an enrichment culture of novel thermophilic anaerobic bacteria.

PubMed

Ghosh, P; Mandal, S; Pal, S; Bandyopadhyaya, G; Chattopadhyay, B D

2006-04-01

In the biosphere, bacteria can function as geo-chemical agents, promoting the dispersion, fractionation and/or concentration of materials. Microbial mineral precipitation is resulted from metabolic activities of microorganisms. Based on this biomineralogy concept, an attempt has been made to develop bioconcrete material incorporating of an enrichment culture of thermophilic and anaerobic bacteria within cement-sand mortar/concrete. The results showed a significant increase in compressive strength of both cement-sand mortar and concrete due to the development of filler material within the pores of cement sand matrix. Maximum strength was observed at concentration 10(5)cell/ml of water used in mortar/concrete. Addition of Escherichia coil or media composition on mortar showed no such improvement in strength.

Molecular diversity, cultivation, and improved detection by fluorescent in situ hybridization of a dominant group of human gut bacteria related to Roseburia spp. or Eubacterium rectale.

PubMed

Aminov, Rustam I; Walker, Alan W; Duncan, Sylvia H; Harmsen, Hermie J M; Welling, Gjalt W; Flint, Harry J

2006-09-01

Phylogenetic analysis was used to compare 16S rRNA sequences from 19 cultured human gut strains of Roseburia and Eubacterium rectale with 356 related sequences derived from clone libraries. The cultured strains were found to represent five of the six phylotypes identified. A new oligonucleotide probe, Rrec584, and the previous group probe Rint623, when used in conjunction with a new helper oligonucleotide, each recognized an average of 7% of bacteria detected by the eubacterial probe Eub338 in feces from 10 healthy volunteers. Most of the diversity within this important group of butyrate-producing gut bacteria can apparently be retrieved through cultivation.

Molecular Diversity, Cultivation, and Improved Detection by Fluorescent In Situ Hybridization of a Dominant Group of Human Gut Bacteria Related to Roseburia spp. or Eubacterium rectale

PubMed Central

Aminov, Rustam I.; Walker, Alan W.; Duncan, Sylvia H.; Harmsen, Hermie J. M.; Welling, Gjalt W.; Flint, Harry J.

2006-01-01

Phylogenetic analysis was used to compare 16S rRNA sequences from 19 cultured human gut strains of Roseburia and Eubacterium rectale with 356 related sequences derived from clone libraries. The cultured strains were found to represent five of the six phylotypes identified. A new oligonucleotide probe, Rrec584, and the previous group probe Rint623, when used in conjunction with a new helper oligonucleotide, each recognized an average of 7% of bacteria detected by the eubacterial probe Eub338 in feces from 10 healthy volunteers. Most of the diversity within this important group of butyrate-producing gut bacteria can apparently be retrieved through cultivation. PMID:16957265

The effect of a multidisciplinary obstetric emergency team training program, the In Time course, on diagnosis to delivery interval following umbilical cord prolapse - A retrospective cohort study.

PubMed

Copson, Sean; Calvert, Katrina; Raman, Puvaneswary; Nathan, Elizabeth; Epee, Mathias

2017-06-01

Cord prolapse is an uncommon obstetric emergency, with potentially fatal consequences for the baby if prompt action is not taken. Simulation training provides a means by which uncommon emergencies can be practised, with the aim of improving teamwork and clinical outcomes. This study aimed to determine if the introduction of a simulation-based training course was associated with an improvement in the management of cord prolapse, in particular the diagnosis to delivery interval. We also aimed to investigate if an improvement in perinatal outcomes could be demonstrated. A retrospective cohort study was performed. All cases of cord prolapse in the designated time period were identified and reviewed and a comparison of outcome measures pre- and post-training was undertaken. Thirty-one cases were identified in the pre-training period, and compared to 64 cases post-training. Documentation improved significantly post-training. There were non-significant improvements in use of spinal anaesthetic, and in the length of stay in the special care neonatal unit. There was a significant increase in the number of babies with Apgar scores less than seven at 5 min. There were no differences in the diagnosis to delivery interval, or in perinatal mortality rates. Obstetric emergency training was associated with improved teamwork, as evidenced by the improved documentation post-training in this study, but not with improved diagnosis to delivery interval. Long-term follow-up studies are required to ascertain whether training has an impact on longer-term paediatric outcomes, such as cerebral palsy rates. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Using operations research to plan improvement of the transport of critically ill patients.

PubMed

Chen, Jing; Awasthi, Anjali; Shechter, Steven; Atkins, Derek; Lemke, Linda; Fisher, Les; Dodek, Peter

2013-01-01

Operations research is the application of mathematical modeling, statistical analysis, and mathematical optimization to understand and improve processes in organizations. The objective of this study was to illustrate how the methods of operations research can be used to identify opportunities to reduce the absolute value and variability of interfacility transport intervals for critically ill patients. After linking data from two patient transport organizations in British Columbia, Canada, for all critical care transports during the calendar year 2006, the steps for transfer of critically ill patients were tabulated into a series of time intervals. Statistical modeling, root-cause analysis, Monte Carlo simulation, and sensitivity analysis were used to test the effect of changes in component intervals on overall duration and variation of transport times. Based on quality improvement principles, we focused on reducing the 75th percentile and standard deviation of these intervals. We analyzed a total of 3808 ground and air transports. Constraining time spent by transport personnel at sending and receiving hospitals was projected to reduce the total time taken by 33 minutes with as much as a 20% reduction in standard deviation of these transport intervals in 75% of ground transfers. Enforcing a policy of requiring acceptance of patients who have life- or limb-threatening conditions or organ failure was projected to reduce the standard deviation of air transport time by 63 minutes and the standard deviation of ground transport time by 68 minutes. Based on findings from our analyses, we developed recommendations for technology renovation, personnel training, system improvement, and policy enforcement. Use of the tools of operations research identifies opportunities for improvement in a complex system of critical care transport.

Process improvement to enhance existing stroke team activity toward more timely thrombolytic treatment.

PubMed

Cho, Han-Jin; Lee, Kyung Yul; Nam, Hyo Suk; Kim, Young Dae; Song, Tae-Jin; Jung, Yo Han; Choi, Hye-Yeon; Heo, Ji Hoe

2014-10-01

Process improvement (PI) is an approach for enhancing the existing quality improvement process by making changes while keeping the existing process. We have shown that implementation of a stroke code program using a computerized physician order entry system is effective in reducing the in-hospital time delay to thrombolysis in acute stroke patients. We investigated whether implementation of this PI could further reduce the time delays by continuous improvement of the existing process. After determining a key indicator [time interval from emergency department (ED) arrival to intravenous (IV) thrombolysis] and conducting data analysis, the target time from ED arrival to IV thrombolysis in acute stroke patients was set at 40 min. The key indicator was monitored continuously at a weekly stroke conference. The possible reasons for the delay were determined in cases for which IV thrombolysis was not administered within the target time and, where possible, the problems were corrected. The time intervals from ED arrival to the various evaluation steps and treatment before and after implementation of the PI were compared. The median time interval from ED arrival to IV thrombolysis in acute stroke patients was significantly reduced after implementation of the PI (from 63.5 to 45 min, p=0.001). The variation in the time interval was also reduced. A reduction in the evaluation time intervals was achieved after the PI [from 23 to 17 min for computed tomography scanning (p=0.003) and from 35 to 29 min for complete blood counts (p=0.006)]. PI is effective for continuous improvement of the existing process by reducing the time delays between ED arrival and IV thrombolysis in acute stroke patients.

Effects of Short-Interval and Long-Interval Swimming Protocols on Performance, Aerobic Adaptations, and Technical Parameters: A Training Study.

PubMed

Dalamitros, Athanasios A; Zafeiridis, Andreas S; Toubekis, Argyris G; Tsalis, George A; Pelarigo, Jailton G; Manou, Vasiliki; Kellis, Spiridon

2016-10-01

Dalamitros, AA, Zafeiridis, AS, Toubekis, AG, Tsalis, GA, Pelarigo, JG, Manou, V, and Kellis, S. Effects of short-interval and long-interval swimming protocols on performance, aerobic adaptations, and technical parameters: A training study. J Strength Cond Res 30(10): 2871-2879, 2016-This study compared 2-interval swimming training programs of different work interval durations, matched for total distance and exercise intensity, on swimming performance, aerobic adaptations, and technical parameters. Twenty-four former swimmers were equally divided to short-interval training group (INT50, 12-16 × 50 m with 15 seconds rest), long-interval training group (INT100, 6-8 × 100 m with 30 seconds rest), and a control group (CON). The 2 experimental groups followed the specified swimming training program for 8 weeks. Before and after training, swimming performance, technical parameters, and indices of aerobic adaptations were assessed. ΙΝΤ50 and ΙΝΤ100 improved swimming performance in 100 and 400-m tests and the maximal aerobic speed (p ≤ 0.05); the performance in the 50-m swim did not change. Posttraining V[Combining Dot Above]O2max values were higher compared with pretraining values in both training groups (p ≤ 0.05), whereas peak aerobic power output increased only in INT100 (p ≤ 0.05). The 1-minute heart rate and blood lactate recovery values decreased after training in both groups (p < 0.01). Stroke length increased in 100 and 400-m swimming tests after training in both groups (p ≤ 0.05); no changes were observed in stroke rate after training. Comparisons between groups on posttraining mean values, after adjusting for pretraining values, revealed no significant differences between ΙΝΤ50 and ΙΝΤ100 for all variables; however, all measures were improved vs. the respective values in the CON (p < 0.001-0.05). In conclusion, when matched for distance and exercise intensity, the short-interval (50 m) and long-interval (100 m) protocols confer analogous improvements in swimming performance, in stroke cycle parameters, and in indices of aerobic adaptations after 8 weeks of training.

Volatile compounds from beneficial or pathogenic bacteria differentially regulate root exudation, transcription of iron transporters, and defense signaling pathways in Sorghum bicolor.

PubMed

Hernández-Calderón, Erasto; Aviles-Garcia, Maria Elizabeth; Castulo-Rubio, Diana Yazmín; Macías-Rodríguez, Lourdes; Ramírez, Vicente Montejano; Santoyo, Gustavo; López-Bucio, José; Valencia-Cantero, Eduardo

2018-02-01

Our results show that Sorghum bicolor is able to recognize bacteria through its volatile compounds and differentially respond to beneficial or pathogens via eliciting nutritional or defense adaptive traits. Plants establish beneficial, harmful, or neutral relationships with bacteria. Plant growth promoting rhizobacteria (PGPR) emit volatile compounds (VCs), which may act as molecular cues influencing plant development, nutrition, and/or defense. In this study, we compared the effects of VCs produced by bacteria with different lifestyles, including Arthrobacter agilis UMCV2, Bacillus methylotrophicus M4-96, Sinorhizobium meliloti 1021, the plant pathogen Pseudomonas aeruginosa PAO1, and the commensal rhizobacterium Bacillus sp. L2-64, on S. bicolor. We show that VCs from all tested bacteria, except Bacillus sp. L2-64, increased biomass and chlorophyll content, and improved root architecture, but notheworthy A. agilis induced the release of attractant molecules, whereas P. aeruginosa activated the exudation of growth inhibitory compounds by roots. An analysis of the expression of iron-transporters SbIRT1, SbIRT2, SbYS1, and SbYS2 and genes related to plant defense pathways COI1 and PR-1 indicated that beneficial, pathogenic, and commensal bacteria could up-regulate iron transporters, whereas only beneficial and pathogenic species could induce a defense response. These results show how S. bicolor could recognize bacteria through their volatiles profiles and highlight that PGPR or pathogens can elicit nutritional or defensive traits in plants.

Validating tyrosinase homologue MelA as a photoacoustic reporter gene for imaging Escherichia coli

NASA Astrophysics Data System (ADS)

Paproski, Robert J.; Li, Yan; Barber, Quinn; Lewis, John D.; Campbell, Robert; Zemp, Roger

2015-03-01

Antibiotic drug resistance is a major worldwide issue. Development of new therapies against pathogenic bacteria requires appropriate research tools for replicating and characterizing infections. Previously fluorescence and bioluminescence modalities have been used to image infectious burden in animal models but scattering significantly limits imaging depth and resolution. We hypothesize that photoacoustic imaging, which has improved depth-toresolution ratio, could be useful for visualizing MelA-expressing bacteria since MelA is a bacterial tyrosinase homologue involved in melanin production. Using an inducible expression system, E. coli expressing MelA were visibly black in liquid culture. Phosphate buffered saline (PBS), MelA-expressing bacteria (at different dilutions in PBS), and chicken embryo blood were injected in plastic tubes which were imaged using a VisualSonics Vevo LAZR system. Photoacoustic imaging at 6 different wavelengths (680, 700, 750, 800, 850 and 900nm) enabled spectral de-mixing to distinguish melanin signals from blood. The signal to noise ratio of 9x diluted MelA bacteria was 55, suggesting that ~20 bacteria cells could be detected with our system. When MelA bacteria were injected as a 100 μL bolus into a chicken embryo, photoacoustic signals from deoxy- and oxy- hemoglobin as well as MelA-expressing bacteria could be separated and overlaid on an ultrasound image, allowing visualization of the bacterial location. Photoacoustic imaging may be a useful tool for visualizing bacterial infections and further work incorporating photoacoustic reporters into infectious bacterial strains is warranted.

Effect of bovine colostrum, cheese whey, and spray-dried porcine plasma on the in vitro growth of probiotic bacteria and Escherichia coli.

PubMed

Champagne, Claude P; Raymond, Yves; Pouliot, Yves; Gauthier, Sylvie F; Lessard, Martin

2014-05-01

The aim of this study is to evaluate the effects of defatted colostrum (Col), defatted decaseinated colostrum whey, cheese whey, and spray-dried porcine plasma (SDPP) as supplements of a growth medium (de Man - Rogosa - Sharpe (MRS) broth) on the multiplication of lactic acid bacteria, probiotic bacteria, and potentially pathogenic Escherichia coli. Using automated spectrophotometry (in vitro system), we evaluated the effect of the 4 supplements on maximum growth rate (μ(max)), lag time (LagT), and biomass (OD(max)) of 12 lactic acid bacteria and probiotic bacteria and of an E. coli culture. Enrichment of MRS broth with a Col concentration of 10 g/L increased the μ(max) of 5 of the 12 strains by up to 55%. Negative effects of Col or SDPP on growth rates were also observed with 3 probiotic strains; in one instance μ(max) was reduced by 40%. The most effective inhibitor of E. coli growth was SDPP, and this effect was not linked to its lysozyme content. The positive effect of enrichment with the dairy-based ingredient might be linked to enrichment in sugars and increased buffering power of the medium. These in vitro data suggest that both Col and SDPP could be considered as supplements to animal feeds to improve intestinal health because of their potential to promote growth of probiotic bacteria and to inhibit growth of pathogenic bacteria such as E. coli.

Distribution and decline of human pathogenic bacteria in soil after application in irrigation water and the potential for soil-splash-mediated dispersal onto fresh produce.

PubMed

Monaghan, J M; Hutchison, M L

2012-05-01

To improve our understanding of the survival and splash-mediated transfer of zoonotic agents and faecal indicator bacteria introduced into soils used for crop cultivation via contaminated irrigation waters. Zoonotic agents and an Escherichia coli marker bacterium were inoculated into borehole water, which was applied to two different soil types in early-, mid- and late summer. Decline of the zoonotic agents was influenced by soil type. Marker bacteria applied to columns of two soil types in irrigation water did not concentrate at the surface of the soils. Decline of zoonotic agents at the surface was influenced by soil type and environmental conditions. Typically, declines were rapid and bacteria were not detectable after 5 weeks. Selective agar strips were used to determine that the impact of water drops 24-87 μl could splash marker bacteria from soil surfaces horizontal distances of at least 25 cm and heights of 20 cm. Soil splash created by rain-sized water droplets can transfer enteric bacteria from soil to ready-to-eat crops. Persistence of zoonotic agents was reduced at the hottest part of the growing season when irrigation is most likely. Soil splash can cause crop contamination. We report the penetration depths and seasonally influenced declines of bacteria applied in irrigation water into two soil types. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Airborne bacterial dispersal during and after dressing and bed changes on burns patients.

PubMed

Bache, Sarah E; Maclean, Michelle; Gettinby, George; Anderson, John G; MacGregor, Scott J; Taggart, Ian

2015-02-01

It is acknowledged that activities such as dressing changes and bed sheet changes are high-risk events; creating surges in levels of airborne bacteria. Burns patients are particularly high dispersers of pathogens; due to their large, often contaminated, wound areas. Prevention of nosocomial cross-contamination is therefore one of the major challenges faced by the burns team. In order to assess the contribution of airborne spread of bacteria, air samples were taken repeatedly throughout and following these events, to quantify levels of airborne bacteria. Air samples were taken at 3-min intervals before, during and after a dressing and bed change on a burns patient using a sieve impaction method. Following incubation, bacterial colonies were enumerated to calculate bacterial colony forming units per m(3) (cfu/m(3)) at each time point. Statistical analysis was performed, whereby the period before the high-risk event took place acted as a control period. The periods during and after the dressing and bed sheet changes were examined for significant differences in airborne bacterial levels relative to the control period. The study was carried out four times, on three patients with burns between 35% total burn surface area (TBSA) and 51% TBSA. There were significant increases in airborne bacteria levels, regardless of whether the dressing change or bed sheet change took place first. Of particular note, is the finding that significantly high levels (up to 2614cfu/m(3)) of airborne bacteria were shown to persist for up to approximately 1h after these activities ended. This is the most accurate picture to date of the rapidly changing levels of airborne bacteria within the room of a burns patient undergoing a dressing change and bed change. The novel demonstration of a significant increase in the airborne bacterial load during these events has implications for infection control on burns units. Furthermore, as these increased levels remained for approximately 1h afterwards, persons entering the room both during and after such events may act as vectors of transmission of infection. It is suggested that appropriate personal protective equipment should be worn by anyone entering the room, and that rooms should be quarantined for a period of time following these events. Airborne bacteria significantly increase during dressing and sheet changes on moderate size burns, and remain elevated for up to an hour following their cessation. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Multibacterial Growth From a Surgical Renal Stone Culture: A Case Report and Literature Review

PubMed Central

Mufarrij, Patrick W; Lange, Jessica N; Assimos, Dean G; Mirzazadeh, Majid; Holmes, Ross P

2012-01-01

Urinary calculi may harbor bacteria, and this may lead to deleterious events during stone fragmentation and removal. The isolation of such bacteria from surgically extracted calculi allows for the specific tailoring of antimicrobial therapy. Here, we describe a case involving percutaneous stone removal from which the stone culture demonstrated growth of five different microorganisms. The results of this culture prompted a change in the antibiotic coverage, resulting in a more targeted treatment and improved patient care. PMID:23524537

Applications Research of Microbial Ecological Preparation in Sea Cucumber Culture

NASA Astrophysics Data System (ADS)

Jiang, Jiahui; Wang, Guangyu

2017-12-01

At present, micro ecological preparation is widely applied in aquaculture with good effect. The application of micro ecological preparation in sea cucumber culture can effectively improve the economic benefits. The micro ecological preparation can play the role of inhibiting harmful bacteria, purifying water quality and saving culture cost in the process of sea cucumber culture. We should select appropriate bacteria, guarantee stable environment and use with long-term in the applications of microbial ecological preparation in sea cucumber culture to obtain good effects.

Effects of Gelling Agent and Extracellular Signaling Molecules on the Culturability of Marine Bacteria

PubMed Central

Rygaard, Anita Mac; Thøgersen, Mariane Schmidt; Nielsen, Kristian Fog; Gram, Lone

2017-01-01

ABSTRACT Only 1% of marine bacteria are currently culturable using standard laboratory procedures, and this is a major obstacle for our understanding of the biology of marine microorganisms and for the discovery of novel microbial natural products. Therefore, the purpose of this study was to investigate if improved cultivation conditions, including the use of an alternative gelling agent and supplementation with signaling molecules, improve the culturability of bacteria from seawater. Replacing agar with gellan gum improved viable counts 3- to 40-fold, depending on medium composition and incubation conditions, with a maximum of 6.6% culturability relative to direct cell counts. Through V4 amplicon sequencing we found that culturable diversity was also affected by a change in gelling agent, facilitating the growth of orders not culturable on agar-based substrates. Community analyses showed that communities grown on gellan gum substrates were significantly different from communities grown on agar and that they covered a larger fraction of the seawater community. Other factors, such as incubation temperature and time, had less obvious effects on viable counts and culturable diversity. Supplementation with acylated homoserine lactones (AHLs) did not have a positive effect on total viable counts or a strong effect on culturable diversity. However, low concentrations of AHLs increased the relative abundance of sphingobacteria. Hence, with alternative growth substrates, it is possible to significantly increase the number and diversity of cultured marine bacteria. IMPORTANCE Serious challenges to human health, such as the occurrence and spread of antibiotic resistance and an aging human population in need of bioactive pharmaceuticals, have revitalized the search for natural microbial products. The marine environment, representing the largest ecosystem in the biosphere, harbors an immense and virtually untapped microbial diversity producing unique bioactive compounds. However, we are currently able to cultivate only a minute fraction of this diversity. The lack of cultivated microbes is hampering not only bioprospecting efforts but also our general understanding of marine microbes. In this study, we present a means to increase the number and diversity of cultured bacteria from seawater, showing that relatively simple changes to medium components may facilitate the isolation and growth of hitherto unknown bacterial orders. PMID:28213548

Improvement in grade of minerals using simultaneous Bio-oxidation of invisible gold concentrate and deep-sea manganese crust

NASA Astrophysics Data System (ADS)

Myung, EunJi; Cho, Kang Hee; Kim, Hyun Soo; Park, Cheon Young

2016-04-01

Many sulfides of metal such as galena, sphalerite, chalcopyrite, and pyrite, are semiconductors. When two kinds of such minerals contact each other in an electrolyte, a galvanic couple, where the mineral of lower rest potential as anode, and that of higher rest potential as cathode forms. Manganese dioxide is also a semiconductor with much higher rest potential than all sulfides mentioned above, so that a galvanic couple in which both the minerals would dissolve simultaneously can form, when it contacts with any of the sulfides. The aim of this study was to investigate the improvement in grade of minerals using the simultaneous bio-oxidation of deep-sea manganese crust and invisible gold concentrate. The samples(deep-sea manganese crust and invisible gold concentrate) were characterized by chemical and XRD analysis. The primary components of the invisible gold concentrate was pyrite and quartz and the deep-sea manganese crust was amorphous material, as detected using XRD. The result of chemical analysis showed that Au, Ag, Te contents in the invisible gold concentrate 130.2, 954.1 and 1,043.6 mg/kg, respectively. and that Mn, Ni, Co contents in the deep-sea manganese crust 19,501.5, 151.9, 400.4 mg/kg, respectively. In order to increase the bacteria's tolerance of heavy metals, the bacteria using bio-oxidation experiments were repeatedly subcultured in an Cu adaptation-medium containing of 382.98 mg/l for 20 periods of 21 days. The improvement in grade of samples of in present adapted bacteria condition was greater than another conditions(control and in present non-adapted bacteria). The Au-Ag-Te contents in the invisible gold concentrate was enhanced in the order of physical oxidation, simultaneous/non-adaptive bio-oxidation, adaptive/bio-oxidation, simultaneous/adaptive bio-oxidation. If the bacteria is adapted to heavy metal ions and an optimization of conditions is found in future bio-oxidation-leaching processes. Acknowledgment : "This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(NRF-2013R1A1A2004898)"

A 100-Year Review: Microbiology and safety of milk handling.

PubMed

Boor, Kathryn J; Wiedmann, Martin; Murphy, Sarah; Alcaine, Sam

2017-12-01

Microbes that may be present in milk can include pathogens, spoilage organisms, organisms that may be conditionally beneficial (e.g., lactic acid bacteria), and those that have not been linked to either beneficial or detrimental effects on product quality or human health. Although milk can contain a full range of organisms classified as microbes (i.e., bacteria, viruses, fungi, and protozoans), with few exceptions (e.g., phages that affect fermentations, fungal spoilage organisms, and, to a lesser extent, the protozoan pathogens Cryptosporidium and Giardia) dairy microbiology to date has focused predominantly on bacteria. Between 1917 and 2017, our understanding of the microbes present in milk and the tools available for studying those microbes have changed dramatically. Improved microbiological tools have enabled enhanced detection of known microbes in milk and dairy products and have facilitated better identification of pathogens and spoilage organisms that were not known or well recognized in the early 20th century. Starting before 1917, gradual introduction and refinement of pasteurization methods throughout the United States and many other parts of the world have improved the safety and quality of milk and dairy products. In parallel to pasteurization, others strategies for reducing microbial contamination throughout the dairy chain (e.g., improved dairy herd health, raw milk tests, clean-in-place technologies) also played an important role in improving microbial milk quality and safety. Despite tremendous advances in reducing microbial food safety hazards and spoilage issues, the dairy industry still faces important challenges, including but not limited to the need for improved science-based strategies for safety of raw milk cheeses, control of postprocessing contamination, and control of sporeforming pathogens and spoilage organisms. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antibacterial properties of silver nanoparticles as a root canal irrigant against Enterococcus faecalis biofilm and infected dentinal tubules.

PubMed

Rodrigues, C T; de Andrade, F B; de Vasconcelos, L R S M; Midena, R Z; Pereira, T C; Kuga, M C; Duarte, M A H; Bernardineli, N

2018-02-03

To evaluate the antimicrobial action of an irrigant containing silver nanoparticles in an aqueous vehicle (AgNp), sodium hypochlorite and chlorhexidine against Enterococcus faecalis biofilm and infected dentinal tubules. Bovine dentine blocks were used for E. faecalis biofilm development for 21 days and irrigated with 94 ppm AgNp solution, 2.5% NaOCl and 2% chlorhexidine for 5, 15 and 30 min. For infection of dentinal tubules with E. faecalis, dentine specimens from bovine incisors were submitted to a contamination protocol over 5 days, with eight centrifugation cycles on every alternate day, and irrigated with the same solutions and time intervals used for the biofilm. The specimens were stained with the Live/Dead technique and evaluated using a confocal laser scanning microscope (CLSM). The bioImage_L software was used for measurement of the total biovolume of biofilm in μm 3 and percentage of viable bacteria (green cells) in biofilm and in dentinal tubules found after the irrigation. Statistical analyses were performed using Kruskal-Wallis and Dunn's tests for quantification of viable cells in biofilm, the Friedman test for comparisons of viable bacteria in dentinal tubules in different areas of the root canal and the Mann-Whitney U-test to compare the action of the irrigants between the two methods (P < 0.05). The AgNp solution eliminated fewer bacteria, but was able to dissolve more biofilm compared with chlorhexidine (P < 0.05). NaOCl had the greatest antimicrobial activity and biofilm dissolution capacity. AgNp solution had less antimicrobial action in infected dentinal tubules compared with NaOCl (P < 0.05). The AgNp solution after 5 min was more effective in eliminating planktonic bacteria in dentinal tubules than in biofilm, but at 30 min fewer viable bacteria were observed in the biofilm compared with intratubular dentine (P < 0.05). AgNp irrigant was not as effective against E. faecalis compared to solutions commonly used in root canal treatment. NaOCl is appropriate as an irrigant because it was effective in disrupting biofilm and in eliminating bacteria in biofilms and in dentinal tubules. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Clinical characteristics and outcomes of prosthetic joint infection caused by small colony variant staphylococci.

PubMed

Tande, Aaron J; Osmon, Douglas R; Greenwood-Quaintance, Kerryl E; Mabry, Tad M; Hanssen, Arlen D; Patel, Robin

2014-09-30

Small colony variants (SCVs) are naturally occurring subpopulations of bacteria. The clinical characteristics and treatment outcomes of patients with prosthetic joint infection (PJI) caused by staphylococcal SCVs are unknown. This study was a retrospective series of 113 patients with staphylococcal PJI, with prospective testing of archived sonicate fluid samples. SCVs were defined using two-investigator review. Treatment failure was defined as (i) subsequent revision surgery for any reason, (ii) PJI after the index surgery, (iii) prosthesis nonreimplantation due to ongoing infection, or (iv) amputation of the affected limb. There were 38 subjects (34%) with SCVs and 75 (66%) with only normal-phenotype (NP) bacteria. Subjects with SCVs were more likely to have been on chronic antimicrobials prior to surgery (P = 0.048), have had prior surgery for PJI (P = 0.03), have had a longer duration of symptoms (P = 0.0003), and have had a longer time since joint implantation (P = 0.007), compared to those with only NP bacteria. Over a median follow-up of 30.6 months, 9 subjects (24%) with SCVs and 23 (32%) with only NP bacteria experienced treatment failure (P = 0.51). Subjects infected with Staphylococcus aureus were more likely to fail than were those infected with Staphylococcus epidermidis (hazard ratio [HR], 4.03; 95% confidence interval [CI], 1.80 to 9.04). While frequently identified in subjects with PJI and associated with several potential predisposing factors, SCVs were not associated with excess treatment failure compared to NP infections in this study, where they were primarily managed with two-stage arthroplasty exchange. Bacteria with the small colony variant (SCV) phenotype are described in small case series as causing persistent or relapsing infection, but there are insufficient data to suggest that they should be managed differently than infection with normal-phenotype bacteria. In an effort to investigate the clinical importance of this phenotype, we determined whether SCVs were present in biofilms dislodged from the surfaces of arthroplasties of patients with staphylococcal prosthetic joint infection and assessed the clinical outcomes associated with detection of SCVs. We found that prosthetic joint infection caused by SCV staphylococci was associated with a longer duration of symptoms and more prior treatment for infection but not with an increased rate of treatment failure, compared to infection caused by normal-phenotype staphylococci. Copyright © 2014 Tande et al.

Enhanced Retention of Chemotactic Bacteria in a Pore Network with Residual NAPL Contamination

NASA Astrophysics Data System (ADS)

Ford, R.; Wang, X.

2013-12-01

Nonaqueous phase liquid (NAPL) contaminants are difficult to eliminate from natural aquifers due, in part, to the heterogeneous structure of the soil matrix. Residual NAPL ganglia remain trapped in regions where the hydraulic conductivity is relatively low. Bioremediation processes depend on adequate mixing of microbial populations and the groundwater contaminants that they degrade. The ability of bacteria to sense a chemical gradient and swim preferentially toward locations of higher concentration, known as chemotaxis, can enhance the mixing of bacteria with contaminant sources that may not be readily accessible by advection and dispersion alone. The impact of chemotaxis on bacterial abundance within a low conductivity NAPL-contaminated region of a well-characterized porous matrix was investigated. A microfluidic device was designed to mimic heterogeneous features of a contaminated groundwater system. NAPL ganglia (toluene) were trapped within a fine pore network, and bacteria were injected into the system through a highly conductive adjacent channel. Chemotactic bacteria (P. putida F1) migrated preferentially towards and accumulated in the vicinity of NAPL contaminant sources. The accumulation of chemotactic bacteria was 15% greater in comparison to a nonchemotactic mutant (P. putida F1 CheA). Bacteria in the microfluidic device were subjected to different flow velocities from 0.25 to 5 m/d encompassing the range of typical groundwater flow rates. Chemotactic bacteria exhibited greater accumulation near the intersection between the macrochannel and the porous network at a flow velocity of 0.5 m/d than both the nonchemotactic mutant control and the chemotactic bacteria at a higher flow velocity of 5 m/d. Breakthrough curves observed at the outlet provided indirect evidence that chemotactic bacteria were retained within the contaminated low permeable region for a longer time than the nonchemotactic bacteria at a flow velocity of 0.25 m/d. This retention was diminished at a higher flow velocity of 5 m/d. Numerical solutions of the governing equations for bacterial transport yielded outcomes that were consistent with the experimental results, and statistical analysis also supported the experimental comparisons. The chemotactic response aided efficient delivery of bacteria to NAPL contaminant sources within the low conductivity pore network. Because toluene is degraded by P. putida F1, the greater accumulation of chemotactic bacteria around the NAPL sources is also expected to increase contaminant consumption and improve the efficiency of bioremediation.

Department of Defense Precise Time and Time Interval program improvement plan

NASA Technical Reports Server (NTRS)

Bowser, J. R.

1981-01-01

The United States Naval Observatory is responsible for ensuring uniformity in precise time and time interval operations including measurements, the establishment of overall DOD requirements for time and time interval, and the accomplishment of objectives requiring precise time and time interval with minimum cost. An overview of the objectives, the approach to the problem, the schedule, and a status report, including significant findings relative to organizational relationships, current directives, principal PTTI users, and future requirements as currently identified by the users are presented.

Population-Based Pediatric Reference Intervals in General Clinical Chemistry: A Swedish Survey.

PubMed

Ridefelt, Peter

2015-01-01

Very few high quality studies on pediatric reference intervals for general clinical chemistry and hematology analytes have been performed. Three recent prospective community-based projects utilising blood samples from healthy children in Sweden, Denmark and Canada have substantially improved the situation. The Swedish survey included 701 healthy children. Reference intervals for general clinical chemistry and hematology were defined.

An algorithm for calculating the contour Voigt and its improvement and refinement for some ranges of parameters

NASA Astrophysics Data System (ADS)

Sukhanov, AY

2017-02-01

We present an approximation Voigt contour for some parameters intervals such as the interval with y less than 0.02 and absolute value x less than 1.6 gives a simple formula for calculating and relative error less than 0.1%, and for some of the intervals suggetsted to use Hermite quadrature.

a New Approach for Accuracy Improvement of Pulsed LIDAR Remote Sensing Data

NASA Astrophysics Data System (ADS)

Zhou, G.; Huang, W.; Zhou, X.; He, C.; Li, X.; Huang, Y.; Zhang, L.

2018-05-01

In remote sensing applications, the accuracy of time interval measurement is one of the most important parameters that affect the quality of pulsed lidar data. The traditional time interval measurement technique has the disadvantages of low measurement accuracy, complicated circuit structure and large error. A high-precision time interval data cannot be obtained in these traditional methods. In order to obtain higher quality of remote sensing cloud images based on the time interval measurement, a higher accuracy time interval measurement method is proposed. The method is based on charging the capacitance and sampling the change of capacitor voltage at the same time. Firstly, the approximate model of the capacitance voltage curve in the time of flight of pulse is fitted based on the sampled data. Then, the whole charging time is obtained with the fitting function. In this method, only a high-speed A/D sampler and capacitor are required in a single receiving channel, and the collected data is processed directly in the main control unit. The experimental results show that the proposed method can get error less than 3 ps. Compared with other methods, the proposed method improves the time interval accuracy by at least 20 %.

Alternative bacteriophage life cycles: the carrier state of Campylobacter jejuni

PubMed Central

Siringan, Patcharin; Connerton, Phillippa L.; Cummings, Nicola J.; Connerton, Ian F.

2014-01-01

Members of the genus Campylobacter are frequently responsible for human enteric disease, often through consumption of contaminated poultry products. Bacteriophages are viruses that have the potential to control pathogenic bacteria, but understanding their complex life cycles is key to their successful exploitation. Treatment of Campylobacter jejuni biofilms with bacteriophages led to the discovery that phages had established a relationship with their hosts typical of the carrier state life cycle (CSLC), where bacteria and bacteriophages remain associated in equilibrium. Significant phenotypic changes include improved aerotolerance under nutrient-limited conditions that would confer an advantage to survive in extra-intestinal environments, but a lack in motility eliminated their ability to colonize chickens. Under these circumstances, phages can remain associated with a compatible host and continue to produce free virions to prospect for new hosts. Moreover, we demonstrate that CSLC host bacteria can act as expendable vehicles for the delivery of bacteriophages to new host bacteria within pre-colonized chickens. The CSLC represents an important phase in the ecology of Campylobacter bacteriophage. PMID:24671947

Alternative bacteriophage life cycles: the carrier state of Campylobacter jejuni.

PubMed

Siringan, Patcharin; Connerton, Phillippa L; Cummings, Nicola J; Connerton, Ian F

2014-03-26

Members of the genus Campylobacter are frequently responsible for human enteric disease, often through consumption of contaminated poultry products. Bacteriophages are viruses that have the potential to control pathogenic bacteria, but understanding their complex life cycles is key to their successful exploitation. Treatment of Campylobacter jejuni biofilms with bacteriophages led to the discovery that phages had established a relationship with their hosts typical of the carrier state life cycle (CSLC), where bacteria and bacteriophages remain associated in equilibrium. Significant phenotypic changes include improved aerotolerance under nutrient-limited conditions that would confer an advantage to survive in extra-intestinal environments, but a lack in motility eliminated their ability to colonize chickens. Under these circumstances, phages can remain associated with a compatible host and continue to produce free virions to prospect for new hosts. Moreover, we demonstrate that CSLC host bacteria can act as expendable vehicles for the delivery of bacteriophages to new host bacteria within pre-colonized chickens. The CSLC represents an important phase in the ecology of Campylobacter bacteriophage.

[A Case of Hyperammonemia Caused by Urinary Tract Infection Due to Urease-Producing Bacteria].

PubMed

Emura, Masahiro; Tsuchihashi, Kazunari; Shimizu, Yosuke; Kanamaru, Sojun; Matoba, Shun; Ito, Noriyuki

2016-08-01

We present here a rare case of hyperammonemia without liver dysfunction or portal-systemic shunting. The patient was an 80-year-old woman with a history of neurogenic bladder. She was admitted to a nearby hospital for vomiting, diarrhea and consciousness disturbance. Two days after admission, she was transferred to our hospital because of persistant consciousness disturbance. Laboratory data revealed hyperammonemia, but there was no indication of liver dysfunction. Moreover abdominal computed tomography did not reveal any clear finding of liver disease or portal-systemic shunting, but we noted multiple large bladder diverticula. Antibiotic therapy, tracheal intubation, ventilator management and bladder catheterization were performed. The patient's level of consciousness improved rapidly. Urinary culture revealed Bacteroides ureolyticus (urease-producing bacteria). The patient was diagnosed with hyperammonemia and a urinary tract infection due to urease-producing bacteria. Thus, physicians should be aware that obstructive urinary tract infections due to urease-producing bacteria can also be the cause of hyperammonemia.

Review - Lactic acid bacteria in traditional fermented Asian foods.

PubMed

Azam, Mariya; Mohsin, Mashkoor; Ijaz, Hira; Tulain, Ume Ruqia; Ashraf, Muhammad Adnan; Fayyaz, Ahad; Abadeen, Zainul; Kamran, Qindeel

2017-09-01

Lactic acid bacteria play vital roles in various fermented foods in Asia. This paper reviews many types of the world's lactic acid fermented foods and discusses the beneficial effects of lactic acid fermentation of food. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella. Lactic acid bacteria (LAB) are involved in many fermentation processes of Asian traditional foods, demonstrating their profound effects on improving food quality and food safety. During the past few decades' interest has arisen in the use of the varied antagonistic activities of LAB to extent the shelf-life of protein-rich products such as meats and fish. This review article outlines the main types of LAB fermentation as well as their typical fermented foods such as idli, kishk, sauerkraut, koumiss, Suan-tsai, stinky tofu, Chinese sausage and kefir. The roles of LAB and the reasons for their common presence are also discussed.

Advanced nutrient removal from surface water by a consortium of attached microalgae and bacteria: A review.

PubMed

Liu, Junzhuo; Wu, Yonghong; Wu, Chenxi; Muylaert, Koenraad; Vyverman, Wim; Yu, Han-Qing; Muñoz, Raúl; Rittmann, Bruce

2017-10-01

Innovative and cost-effective technologies for advanced nutrient removal from surface water are urgently needed for improving water quality. Conventional biotechnologies, such as ecological floating beds, or constructed wetlands, are not effective in removing nutrients present at low-concentration. However, microalgae-bacteria consortium is promising for advanced nutrient removal from wastewater. Suspended algal-bacterial systems can easily wash out unless the hydraulic retention time is long, attached microalgae-bacteria consortium is more realistic. This critical review summarizes the fundamentals and status of attached microalgae-bacteria consortium for advanced nutrient removal from surface water. Key advantages are the various nutrient removal pathways, reduction of nutrients to very low concentration, and diversified photobioreactor configurations. Challenges include poor identification of functional species, poor control of the community composition, and long start-up times. Future research should focus on the selection and engineering of robust microbial species, mathematical modelling of the composition and functionality of the consortium, and novel photobioreactor configurations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Precision genome engineering in lactic acid bacteria

PubMed Central

2014-01-01

Innovative new genome engineering technologies for manipulating chromosomes have appeared in the last decade. One of these technologies, recombination mediated genetic engineering (recombineering) allows for precision DNA engineering of chromosomes and plasmids in Escherichia coli. Single-stranded DNA recombineering (SSDR) allows for the generation of subtle mutations without the need for selection and without leaving behind any foreign DNA. In this review we discuss the application of SSDR technology in lactic acid bacteria, with an emphasis on key factors that were critical to move this technology from E. coli into Lactobacillus reuteri and Lactococcus lactis. We also provide a blueprint for how to proceed if one is attempting to establish SSDR technology in a lactic acid bacterium. The emergence of CRISPR-Cas technology in genome engineering and its potential application to enhancing SSDR in lactic acid bacteria is discussed. The ability to perform precision genome engineering in medically and industrially important lactic acid bacteria will allow for the genetic improvement of strains without compromising safety. PMID:25185700

Six Sessions of Sprint Interval Training Improves Running Performance in Trained Athletes.

PubMed

Koral, Jerome; Oranchuk, Dustin J; Herrera, Roberto; Millet, Guillaume Y

2018-03-01

Koral, J, Oranchuk, DJ, Herrera, R, and Millet, GY. Six sessions of sprint interval training improves running performance in trained athletes. J Strength Cond Res 32(3): 617-623, 2018-Sprint interval training (SIT) is gaining popularity with endurance athletes. Various studies have shown that SIT allows for similar or greater endurance, strength, and power performance improvements than traditional endurance training but demands less time and volume. One of the main limitations in SIT research is that most studies were performed in a laboratory using expensive treadmills or ergometers. The aim of this study was to assess the performance effects of a novel short-term and highly accessible training protocol based on maximal shuttle runs in the field (SIT-F). Sixteen (12 male, 4 female) trained trail runners completed a 2-week procedure consisting of 4-7 bouts of 30 seconds at maximal intensity interspersed by 4 minutes of recovery, 3 times a week. Maximal aerobic speed (MAS), time to exhaustion at 90% of MAS before test (Tmax at 90% MAS), and 3,000-m time trial (TT3000m) were evaluated before and after training. Data were analyzed using a paired samples t-test, and Cohen's (d) effect sizes were calculated. Maximal aerobic speed improved by 2.3% (p = 0.01, d = 0.22), whereas peak power (PP) and mean power (MP) increased by 2.4% (p = 0.009, d = 0.33) and 2.8% (p = 0.002, d = 0.41), respectively. TT3000m was 6% shorter (p < 0.001, d = 0.35), whereas Tmax at 90% MAS was 42% longer (p < 0.001, d = 0.74). Sprint interval training in the field significantly improved the 3,000-m run, time to exhaustion, PP, and MP in trained trail runners. Sprint interval training in the field is a time-efficient and cost-free means of improving both endurance and power performance in trained athletes.

Six Sessions of Sprint Interval Training Improves Running Performance in Trained Athletes

PubMed Central

Oranchuk, Dustin J.; Herrera, Roberto; Millet, Guillaume Y.

2018-01-01

Abstract Koral, J, Oranchuk, DJ, Herrera, R, and Millet, GY. Six sessions of sprint interval training improves running performance in trained athletes. J Strength Cond Res 32(3): 617–623, 2018—Sprint interval training (SIT) is gaining popularity with endurance athletes. Various studies have shown that SIT allows for similar or greater endurance, strength, and power performance improvements than traditional endurance training but demands less time and volume. One of the main limitations in SIT research is that most studies were performed in a laboratory using expensive treadmills or ergometers. The aim of this study was to assess the performance effects of a novel short-term and highly accessible training protocol based on maximal shuttle runs in the field (SIT-F). Sixteen (12 male, 4 female) trained trail runners completed a 2-week procedure consisting of 4–7 bouts of 30 seconds at maximal intensity interspersed by 4 minutes of recovery, 3 times a week. Maximal aerobic speed (MAS), time to exhaustion at 90% of MAS before test (Tmax at 90% MAS), and 3,000-m time trial (TT3000m) were evaluated before and after training. Data were analyzed using a paired samples t-test, and Cohen's (d) effect sizes were calculated. Maximal aerobic speed improved by 2.3% (p = 0.01, d = 0.22), whereas peak power (PP) and mean power (MP) increased by 2.4% (p = 0.009, d = 0.33) and 2.8% (p = 0.002, d = 0.41), respectively. TT3000m was 6% shorter (p < 0.001, d = 0.35), whereas Tmax at 90% MAS was 42% longer (p < 0.001, d = 0.74). Sprint interval training in the field significantly improved the 3,000-m run, time to exhaustion, PP, and MP in trained trail runners. Sprint interval training in the field is a time-efficient and cost-free means of improving both endurance and power performance in trained athletes. PMID:29076961

Infection with high proportion of multidrug-resistant bacteria in conflict-related injuries is associated with poor outcomes and excess resource consumption: a cohort study of Syrian patients treated in Jordan.

PubMed

Älgå, Andreas; Wong, Sidney; Shoaib, Muhammad; Lundgren, Kalle; Giske, Christian G; von Schreeb, Johan; Malmstedt, Jonas

2018-05-22

Armed conflicts are a major contributor to injury and death globally. Conflict-related injuries are associated with a high risk of wound infection, but it is unknown to what extent infection directly relates to sustainment of life and restoration of function. The aim of this study was to investigate the outcome and resource consumption among civilians receiving acute surgical treatment due to conflict-related injuries. Patients with and without wound infections were compared. We performed a cohort study using routinely collected data from 457 consecutive Syrian civilians that received surgical treatment for acute conflict-related injuries during 2014-2016 at a Jordanian hospital supported by Médecins Sans Frontières. We defined wound infection as clinical signs of infection verified by a positive culture. We used logistic regression models to evaluate infection-related differences in outcome and resource consumption. Wound infection was verified in 49/457 (11%) patients. Multidrug-resistance (MDR) was detected in 36/49 (73%) of patients with infection. Among patients with infection, 11/49 (22%) were amputated, compared to 37/408 (9%) without infection, crude relative risk = 2.62 (95% confidence interval 1.42-4.81). Infected patients needed 12 surgeries on average, compared to five in non-infected patients (p < .00001). Mean length of stay was 77 days for patients with infection, and 35 days for patients without infection (p = .000001). Among Syrian civilians, infected conflict-related wounds had a high prevalence of MDR bacteria. Wound infection was associated with poor outcomes and high resource consumption. These results could guide the development of antibiotic protocols and adaptations of surgical management to improve care for wound infections in conflict-related injuries. ClinicalTrials.gov ( NCT02744144 ). Registered April 13, 2016. Retrospectively registered.

Effect of Various Organic Matter stimulates Bacteria and Arbuscular Mycorrhizal Fungi Plantations on Eroded Slopes in Nepal

NASA Astrophysics Data System (ADS)

Shrestha Vaidya, G.; Shrestha, K.; Wallander, H.

2009-04-01

Erosion resulting from landslides is a serious problem in mountainous countries such as Nepal. To restore such sites it is essential to establish plant cover that protects the soil and reduces erosion. Trees and shrubs on the lower hillsides in Nepal form symbiosis with arbuscular mycorrhizal (AM) fungi and these fungi are important for the uptake of mineral nutrients from the soil. In addition, the mycelia formed by these fungi have an important function in stabilizing the soil. The success of plantations of these eroded slopes is therefore highly dependent on the extent of mycorrhizal colonization of the plants. Mycorrhizal fungi growing in symbiosis with plants are essential in this respect because they improve both plant and nutrient uptake and soil structure. We investigated the influence of organic matter and P amendment on recently produced biomass of bacteria and arbuscular mycorrhizal (AM) fungi in eroded slopes in Nepal. Eroded soil mixed with different types of organic matter was placed in mesh bags which were buried around the trees of Bauhinia purpurea and Leucaena diversifolia .This experiment were done in two seasons ( (the wet and the dry season). Signature fatty acids were used to determine bacterial and AM fungal biomass after the six month intervals. The amount and composition of AM fungal spores were analyzed in the mesh bags from the wet and dry seasons. More microbial biomass was produced during wet season than during dry season. Further more, organic matter addition enhanced the production of AM fungal and bacterial biomass during both seasons. The positive influence of organic matter addition on AM fungi could be an important contribution to plant survival, growth and nutrient composition in the soil in plantations on eroded slopes. Different AM spore communities and bacterial profiles were obtained with different organic amendments and this suggests a possible way of selecting for specific microbial communities in the management of eroded sites.

Incidence, etiology, and outcome of bacterial meningitis in infants aged <90 days in the United kingdom and Republic of Ireland: prospective, enhanced, national population-based surveillance.

PubMed

Okike, Ifeanyichukwu O; Johnson, Alan P; Henderson, Katherine L; Blackburn, Ruth M; Muller-Pebody, Berit; Ladhani, Shamez N; Anthony, Mark; Ninis, Nelly; Heath, Paul T

2014-11-15

Bacterial meningitis remains a major cause of morbidity and mortality in young infants. Understanding the epidemiology and burden of disease is important. Prospective, enhanced, national population-based active surveillance was undertaken to determine the incidence, etiology, and outcome of bacterial meningitis in infants aged <90 days in the United Kingdom and Ireland. During July 2010-July 2011, 364 cases were identified (annual incidence, 0.38/1000 live births; 95% confidence interval [CI], .35-.42). In England and Wales, the incidence of confirmed neonatal bacterial meningitis was 0.21 (n = 167; 95% CI, .18-.25). A total of 302 bacteria were isolated in 298 (82%) of the cases. The pathogens responsible varied by route of admission, gestation at birth, and age at infection. Group B Streptococcus (GBS) (150/302 [50%]; incidence, 0.16/1000 live births; 95% CI, .13-.18) and Escherichia coli (41/302 [14%]; incidence, 0.04/1000; 95% CI, .03-.06) were responsible for approximately two-thirds of identified bacteria. Pneumococcal (28/302 [9%]) and meningococcal (23/302 [8%]) meningitis were rare in the first month, whereas Listeria meningitis was seen only in the first month of life (11/302 [4%]). In hospitalized preterm infants, the etiology of both early- and late-onset meningitis was more varied. Overall case fatality was 8% (25/329) and was higher for pneumococcal meningitis (5/26 [19%]) than GBS meningitis (7/135 [5%]; P = .04) and for preterm (15/90 [17%]) compared with term (10/235 [4%]; P = .0002) infants. The incidence of bacterial meningitis in young infants remains unchanged since the 1980s and is associated with significant case fatality. Prevention strategies and guidelines to improve the early management of cases should be prioritized. © 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.

Nasopharyngeal colonization by potentially pathogenic bacteria found in healthy semi-captive wild-born chimpanzees in Uganda.

PubMed

Mugisha, Lawrence; Köndgen, Sophie; Kaddu-Mulindwa, Deogratias; Gaffikin, Lynne; Leendertz, Fabian H

2014-02-01

Information on the chimpanzee nasopharygeal colonization in captive sanctuaries and in the wild is rare. This study was undertaken to establish the nasopharygeal colonization and potential bacterial pathogens in sanctuary chimpanzees as a basis for improving chimpanzee and employee health. Nasopharygeal colonization of 39 healthy chimpanzees were analyzed by microbiological cultivation method and polymerase chain reaction (PCR) targeting the bacterial 16S rRNA gene. We report four major phyla dominated by Proteobacteria (50%), Fermicutes (35.7%), Bacteriodes (7.1%), and Cynobacteria (7.1%) in healthy semi-captive chimpanzees. Further classification based on 7-base oligomers revealed the following genera: Streptococcus, Veillonella, Neisseria, Prevotella, Kingella and unclassified Cynobacteria, Actinobacillus, Bacteriodes and Pasteurellaceae. On microbiological cultivation we were able to identify and characterize some of the bacteria to species level as Klebsiella pneumonie and Pseudomonas aeruginosa being dominant bacteria with 54.7% and 50% colonization, respectively. Of these, Streptococcus, Neisseria, Klebsiella, and Haemophillus have representatives known to potentially cause severe respiratory disease. Our data present important information on chimpanzee nasopharygeal colonization as a guide to understanding disease processes and pharmaceutical therapies required for improving the health of chimpanzees. The results from this study will guide the processes to improve procedures for routine management of sanctuary chimpanzees and use it as a basis for evaluation of future reintroduction possibilities. © 2013 Wiley Periodicals, Inc.

Current status and emerging role of glutathione in food grade lactic acid bacteria

PubMed Central

2012-01-01

Lactic acid bacteria (LAB) have taken centre stage in perspectives of modern fermented food industry and probiotic based therapeutics. These bacteria encounter various stress conditions during industrial processing or in the gastrointestinal environment. Such conditions are overcome by complex molecular assemblies capable of synthesizing and/or metabolizing molecules that play a specific role in stress adaptation. Thiols are important class of molecules which contribute towards stress management in cell. Glutathione, a low molecular weight thiol antioxidant distributed widely in eukaryotes and Gram negative organisms, is present sporadically in Gram positive bacteria. However, new insights on its occurrence and role in the latter group are coming to light. Some LAB and closely related Gram positive organisms are proposed to possess glutathione synthesis and/or utilization machinery. Also, supplementation of glutathione in food grade LAB is gaining attention for its role in stress protection and as a nutrient and sulfur source. Owing to the immense benefits of glutathione, its release by probiotic bacteria could also find important applications in health improvement. This review presents our current understanding about the status of glutathione and its role as an exogenously added molecule in food grade LAB and closely related organisms. PMID:22920585

Systems solutions by lactic acid bacteria: from paradigms to practice

PubMed Central

2011-01-01

Lactic acid bacteria are among the powerhouses of the food industry, colonize the surfaces of plants and animals, and contribute to our health and well-being. The genomic characterization of LAB has rocketed and presently over 100 complete or nearly complete genomes are available, many of which serve as scientific paradigms. Moreover, functional and comparative metagenomic studies are taking off and provide a wealth of insight in the activity of lactic acid bacteria used in a variety of applications, ranging from starters in complex fermentations to their marketing as probiotics. In this new era of high throughput analysis, biology has become big science. Hence, there is a need to systematically store the generated information, apply this in an intelligent way, and provide modalities for constructing self-learning systems that can be used for future improvements. This review addresses these systems solutions with a state of the art overview of the present paradigms that relate to the use of lactic acid bacteria in industrial applications. Moreover, an outlook is presented of the future developments that include the transition into practice as well as the use of lactic acid bacteria in synthetic biology and other next generation applications. PMID:21995776

Bacterial swimmers that infiltrate and take over the biofilm matrix

PubMed Central

Houry, Ali; Gohar, Michel; Deschamps, Julien; Tischenko, Ekaterina; Aymerich, Stéphane; Gruss, Alexandra; Briandet, Romain

2012-01-01

Bacteria grow in either planktonic form or as biofilms, which are attached to either inert or biological surfaces. Both growth forms are highly relevant states in nature and of paramount scientific focus. However, interchanges between bacteria in these two states have been little explored. We discovered that a subpopulation of planktonic bacilli is propelled by flagella to tunnel deep within a biofilm structure. Swimmers create transient pores that increase macromolecular transfer within the biofilm. Irrigation of the biofilm by swimmer bacteria may improve biofilm bacterial fitness by increasing nutrient flow in the matrix. However, we show that the opposite may also occur (i.e., swimmers can exacerbate killing of biofilm bacteria by facilitating penetration of toxic substances from the environment). We combined these observations with the fact that numerous bacteria produce antimicrobial substances in nature. We hypothesized and proved that motile bacilli expressing a bactericide can also kill a heterologous biofilm population, Staphylococcus aureus in this case, and then occupy the newly created space. These findings identify microbial motility as a determinant of the biofilm landscape and add motility to the complement of traits contributing to rapid alterations in biofilm populations. PMID:22773813

Dual-coated lactic acid bacteria: an emerging innovative technology in the field of probiotics.

PubMed

Alvarez-Calatayud, Guillermo; Margolles, Abelardo

2016-01-01

Probiotics are living micro-organisms that do not naturally have shelf life, and normally are weakly protected against the digestive action of the GI tract. A new dual coating technology has been developed in an effort to maximize survival, that is, to be able to reach the intestine alive and in sufficient numbers to confer the beneficial health effects on the host. Dual-coating of lactic acid bacteria (LAB) is the result of fourth-generation coating technology for the protection of these bacteria at least 100-fold or greater than the uncoated LAB. This innovative technique involves a first pH-dependent protein layer that protects bacteria from gastric acid and bile salt, and a second polysaccharide matrix that protects bacteria from external factors, such as humidity, temperature and pressure, as well as the digestive action during the passage through the GI tract. Dual-coated probiotic formulation is applicable to different therapeutic areas, including irritable bowel syndrome, atopic dermatitis, acute diarrhea, chronic constipation, Helicobacter pylori eradication, and prevention of antibiotic-associated diarrhea. An updated review of the efficacy of doubly coated probiotic strains for improving bacterial survival in the intestinal tract and its consequent clinical benefits in humans is here presented.

Thermostable 𝜶-Amylase Activity from Thermophilic Bacteria Isolated from Bora Hot Spring, Central Sulawesi

NASA Astrophysics Data System (ADS)

Gazali, F. M.; Suwastika, I. N.

2018-03-01

α-Amylase is one of the most important enzyme in biotechnology field, especially in industrial application. Thermostability of α-Amylase produced by thermophilic bacteria improves industrial process of starch degradation in starch industry. The present study were concerned to the characterization of α-Amylase activity from indigenous thermophilic bacteria isolated from Bora hot spring, Central Sulawesi. There were 18 isolates which had successfully isolated from 90°C sediment samples of Bora hot spring and 13 of them showed amylolytic activity. The α-Amylase activity was measured qualitatively at starch agar and quantitatively based on DNS (3,5-Dinitrosalicylic acid) methods, using maltose as standard solution. Two isolates (out of 13 amylolytic bacteria), BR 002 and BR 015 showed amylolytic index of 0.8 mm and 0.5 mm respectively, after being incubated at 55°C in the 0.002% Starch Agar Medium. The α-Amylase activity was further characterized quantitatively which includes the optimum condition of pH and temperature of α-Amylase crude enzyme from each isolate. To our knowledge, this is the first report on isolation and characterization of a thermostable α-Amylase from thermophilic bacteria isolated from Central Sulawesi particularly from Bora hot spring.

Contrasting microbial community changes during mass extinctions at the Middle/Late Permian and Permian/Triassic boundaries

NASA Astrophysics Data System (ADS)

Xie, Shucheng; Algeo, Thomas J.; Zhou, Wenfeng; Ruan, Xiaoyan; Luo, Genming; Huang, Junhua; Yan, Jiaxin

2017-02-01

Microbial communities are known to expand as a result of environmental deterioration during mass extinctions, but differences in microbial community changes between extinction events and their underlying causes have received little study to date. Here, we present a systematic investigation of microbial lipid biomarkers spanning ∼20 Myr (Middle Permian to Early Triassic) at Shangsi, South China, to contrast microbial changes associated with the Guadalupian-Lopingian boundary (GLB) and Permian-Triassic boundary (PTB) mass extinctions. High-resolution analysis of the PTB crisis interval reveals a distinct succession of microbial communities based on secular variation in moretanes, 2-methylhopanes, aryl isoprenoids, steranes, n-alkyl cyclohexanes, and other biomarkers. The first episode of the PTB mass extinction (ME1) was associated with increases in red algae and nitrogen-fixing bacteria along with evidence for enhanced wildfires and elevated soil erosion, whereas the second episode was associated with expansions of green sulfur bacteria, nitrogen-fixing bacteria, and acritarchs coinciding with climatic hyperwarming, ocean stratification, and seawater acidification. This pattern of microbial community change suggests that marine environmental deterioration was greater during the second extinction episode (ME2). The GLB shows more limited changes in microbial community composition and more limited environmental deterioration than the PTB, consistent with differences in species-level extinction rates (∼71% vs. 90%, respectively). Microbial biomarker records have the potential to refine our understanding of the nature of these crises and to provide insights concerning possible outcomes of present-day anthropogenic stresses on Earth's ecosystems.

Extended-spectrum β-lactamase-producing bacteria causing community-acquired urinary tract infections in children.

PubMed

Megged, Orli

2014-09-01

Extended-spectrum β-lactamase (ESBL)-producing bacteria are infrequent pathogens of community-acquired (CA) urinary tract infections (UTIs) in children. The aim of this study was to assess the frequency of and identify risk factors for CA-UTIs due to ESBL-producing microorganisms (CA-ESBL-UTI). The medical records of all children diagnosed with CA-ESBL-UTI at our medical center between 2003 and 2013 were reviewed. Patients with non-ESBL-UTIs during the same period were included as controls. Eighty cases of CA-ESBL-UTI were identified. The incidence of ESBL-UTI increased from 2 to 3.8% during the study period. Compared to children with non-ESBL-UTI, those with ESBL were more likely to be of Arab descent, to have underlying medical conditions, to have received antibiotics in the month prior to the UTI and to have been previously hospitalized. The mean duration of hospitalization for patients with an ESBL-UTI was significantly longer than that for patients with a non-ESBL UTI (3.6 vs. 2 days; P = 0.01). In multivariate analysis, Arab ethnicity [odds ratio (OR) 6.1; 95 % confidence interval (CI) 2.7-13.6] and recent antibiotic treatment (OR 4.0; 95 % CI 1.6-10.4) were risk factors for CA-ESBL-UTI. The incidence of CA-ESBL-UTI is rising. The empiric treatment for suspected UTI in children who had been previously hospitalized and who had received antibiotics in the last month should cover ESBL-producing bacteria.

A Three-Year Follow-Up Study of Antibiotic and Metal Residues, Antibiotic Resistance and Resistance Genes, Focusing on Kshipra-A River Associated with Holy Religious Mass-Bathing in India: Protocol Paper.

PubMed

Diwan, Vishal; Purohit, Manju; Chandran, Salesh; Parashar, Vivek; Shah, Harshada; Mahadik, Vijay K; Stålsby Lundborg, Cecilia; Tamhankar, Ashok J

2017-05-29

Antibiotic resistance (ABR) is one of the major health emergencies for global society. Little is known about the ABR of environmental bacteria and therefore it is important to understand ABR reservoirs in the environment and their potential impact on health. Quantitative and qualitative data will be collected during a 3-year follow-up study of a river associated with religious mass-bathing in Central India. Surface-water and sediment samples will be collected from seven locations at regular intervals for 3 years during religious mass-bathing and in absence of it to monitor water-quality, antibiotic residues, resistant bacteria, antibiotic resistance genes and metals. Approval has been obtained from the Ethics Committee of R.D. Gardi Medical College, Ujjain, India (No. 2013/07/17-311). The results will address the issue of antibiotic residues and antibiotic resistance with a focus on a river environment in India within a typical socio-behavioural context of religious mass-bathing. It will enhance our understanding about the relationship between antibiotic residue levels, water-quality, heavy metals and antibiotic resistance patterns in Escherichia coli isolated from river-water and sediment, and seasonal differences that are associated with religious mass-bathing. We will also document, identify and clarify the genetic differences/similarities relating to phenotypic antibiotic resistance in bacteria in rivers during religious mass-bathing or during periods when there is no mass-bathing.

An in vitro study of adherence of coagulase-negative staphylococci to bone chip columns.

PubMed

Lazarovich, Zilia; Boldur, Ida; Reifer, Rachel; Nitzan, Yeshayahu

2006-09-01

Coagulase-negative staphylococci (CNS) have become a dominant cause of bone infections and their adherence to the infected bones is a prerequisite for the initiation of these infections. In the present study we investigated and compared the adherence of CNS bacteria to human, chicken and rabbit bones. The study was performed using columns made of bone powder from the three different sources, and measurement of the extent of adhesion to bones of CNS bacteria as an in vitro model which is based on particles of matrix that are closely related to the natural matrix. The adhesion to rabbit bone was relatively high, while adhesion to both human and chicken bone columns was lower and almost identical. Pretreatment of the CNS bacteria with sodium periodate, beta-galactosidase or proteinase K significantly inhibited by 50-60% the adhesion to human bones. Pretreatment of CNS bacteria with subinhibitory concentrations of vancomycin or tunicamycin increased their adherence to human bones several-fold. When the bones were pretreated with vancomycin a considerable increase in the adhesion rate of the bacteria to human and chicken bones was seen. A smaller increase in adherence was observed after pretreatment of human bones with the antibiotic tunicamycin. Salicylic acid or benzalkonium chloride (BZC) also resulted in an increase in adhesion to these pretreated bones. From the results obtained it seems that pretreatment of the CNS bacteria with certain reagents exposes adhesins on the surface of the CNS bacteria. On the other hand, pretreatment of the bones with other reagents may enable a better exposure of receptors located on the bone cells and, as a consequence, may improve the adhesion of the CNS bacteria to the treated bones.

Nitrogen signalling in plant interactions with associative and endophytic diazotrophic bacteria.

PubMed

Carvalho, T L G; Balsemão-Pires, E; Saraiva, R M; Ferreira, P C G; Hemerly, A S

2014-10-01

Some beneficial plant-interacting bacteria can biologically fix N2 to plant-available ammonium. Biological nitrogen fixation (BNF) is an important source of nitrogen (N) input in agriculture and represents a promising substitute for chemical N fertilizers. Diazotrophic bacteria have the ability to develop different types of root associations with different plant species. Among the highest rates of BNF are those measured in legumes nodulated by endosymbionts, an already very well documented model of plant-diazotrophic bacterial association. However, it has also been shown that economically important crops, especially monocots, can obtain a substantial part of their N needs from BNF by interacting with associative and endophytic diazotrophic bacteria, that either live near the root surface or endophytically colonize intercellular spaces and vascular tissues of host plants. One of the best reported outcomes of this association is the promotion of plant growth by direct and indirect mechanisms. Besides fixing N, these bacteria can also produce plant growth hormones, and some species are reported to improve nutrient uptake and increase plant tolerance against biotic and abiotic stresses. Thus, this particular type of plant-bacteria association consists of a natural beneficial system to be explored; however, the regulatory mechanisms involved are still not clear. Plant N status might act as a key signal, regulating and integrating various metabolic processes that occur during association with diazotrophic bacteria. This review will focus on the recent progress in understanding plant association with associative and endophytic diazotrophic bacteria, particularly on the knowledge of the N networks involved in BNF and in the promotion of plant growth. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Validating tyrosinase homologue melA as a photoacoustic reporter gene for imaging Escherichia coli

NASA Astrophysics Data System (ADS)

Paproski, Robert J.; Li, Yan; Barber, Quinn; Lewis, John D.; Campbell, Robert E.; Zemp, Roger

2015-10-01

To understand the pathogenic processes for infectious bacteria, appropriate research tools are required for replicating and characterizing infections. Fluorescence and bioluminescence imaging have primarily been used to image infections in animal models, but optical scattering in tissue significantly limits imaging depth and resolution. Photoacoustic imaging, which has improved depth-to-resolution ratio compared to conventional optical imaging, could be useful for visualizing melA-expressing bacteria since melA is a bacterial tyrosinase homologue which produces melanin. Escherichia coli-expressing melA was visibly dark in liquid culture. When melA-expressing bacteria in tubes were imaged with a VisualSonics Vevo LAZR system, the signal-to-noise ratio of a 9× dilution sample was 55, suggesting that ˜20 bacteria cells could be detected with our system. Multispectral (680, 700, 750, 800, 850, and 900 nm) analysis of the photoacoustic signal allowed unmixing of melA-expressing bacteria from blood. To compare photoacoustic reporter gene melA (using Vevo system) with luminescent and fluorescent reporter gene Nano-lantern (using Bruker Xtreme In-Vivo system), tubes of bacteria expressing melA or Nano-lantern were submerged 10 mm in 1% Intralipid, spaced between <1 and 20 mm apart from each other, and imaged with the appropriate imaging modality. Photoacoustic imaging could resolve the two tubes of melA-expressing bacteria even when the tubes were less than 1 mm from each other, while bioluminescence and fluorescence imaging could not resolve the two tubes of Nano-lantern-expressing bacteria even when the tubes were spaced 10 mm from each other. After injecting 100-μL of melA-expressing bacteria in the back flank of a chicken embryo, photoacoustic imaging allowed visualization of melA-expressing bacteria up to 10-mm deep into the embryo. Photoacoustic signal from melA could also be separated from deoxy- and oxy-hemoglobin signal observed within the embryo and chorioallantoic membrane. Our results suggest that melA is a useful photoacoustic reporter gene for visualizing bacteria, and further work incorporating photoacoustic reporters into infectious bacterial strains is warranted.

Modelling and regulating of cardio-respiratory response for the enhancement of interval training

PubMed Central

2014-01-01

Background The interval training method has been a well known exercise protocol which helps strengthen and improve one’s cardiovascular fitness. Purpose To develop an effective training protocol to improve cardiovascular fitness based on modelling and analysis of Heart Rate (HR) and Oxygen Uptake (VO2) dynamics. Methods In order to model the cardiorespiratory response to the onset and offset exercises, the (K4b2, Cosmed) gas analyzer was used to monitor and record the heart rate and oxygen uptake for ten healthy male subjects. An interval training protocol was developed for young health users and was simulated using a proposed RC switching model which was presented to accommodate the variations of the cardiorespiratory dynamics to running exercises. A hybrid system model was presented to describe the adaptation process and a multi-loop PI control scheme was designed for the tuning of interval training regime. Results By observing the original data for each subject, we can clearly identify that all subjects have similar HR and VO2 profiles. The proposed model is capable to simulate the exercise responses during onset and offset exercises; it ensures the continuity of the outputs within the interval training protocol. Under some mild assumptions, a hybrid system model can describe the adaption process and accordingly a multi-loop PI controller can be designed for the tuning of interval training protocol. The self-adaption feature of the proposed controller gives the exerciser the opportunity to reach his desired setpoints after a certain number of training sessions. Conclusions The established interval training protocol targets a range of 70-80% of HRmax which is mainly a training zone for the purpose of cardiovascular system development and improvement. Furthermore, the proposed multi-loop feedback controller has the potential to tune the interval training protocol according to the feedback from an individual exerciser. PMID:24499131

Bacterial community structure in the hyperarid core of the Atacama Desert, Chile

USGS Publications Warehouse

Drees, Kevin P.; Neilson, Julia W.; Betancourt, Julio L.; Quade, Jay; Henderson, David A.; Pryor, Barry M.; Maier, Raina M.

2006-01-01

Soils from the hyperarid Atacama Desert of northern Chile were sampled along an east-west elevational transect (23.75 to 24.70 degrees S) through the driest sector to compare the relative structure of bacterial communities. Analysis of denaturing gradient gel electrophoresis (DGGE) profiles from each of the samples revealed that microbial communities from the extreme hyperarid core of the desert clustered separately from all of the remaining communities. Bands sequenced from DGGE profiles of two samples taken at a 22-month interval from this core region revealed the presence of similar populations dominated by bacteria from the Gemmatimonadetes and Planctomycetes phyla.

Impact of Rehabilitation on Outcomes in Patients With Ischemic Stroke: A Nationwide Retrospective Cohort Study in Japan.

PubMed

Yagi, Maiko; Yasunaga, Hideo; Matsui, Hiroki; Morita, Kojiro; Fushimi, Kiyohide; Fujimoto, Masashi; Koyama, Teruyuki; Fujitani, Junko

2017-03-01

We aimed to examine the concurrent effects of timing and intensity of rehabilitation on improving activities of daily living (ADL) among patients with ischemic stroke. Using the Japanese Diagnosis Procedure Combination inpatient database, we retrospectively analyzed consecutive patients with ischemic stroke at admission who received rehabilitation (n=100 719) from April 2012 to March 2014. Early rehabilitation was defined as that starting within 3 days after admission. The average rehabilitation intensity per day was calculated as the total units of rehabilitation during hospitalization divided by the length of hospital stay. A multivariable logistic regression analysis with multiple imputation and an instrumental variable analysis were performed to examine the association of early and intensive rehabilitation with the proportion of improved ADL score. The proportion of improved ADL score was higher in the early and intensive rehabilitation group. The multivariable logistic regression analysis showed that significant improvements in ADL were observed for early rehabilitation (odds ratio: 1.08; 95% confidence interval: 1.04-1.13; P <0.01) and intensive rehabilitation of >5.0 U/d (odds ratio: 1.87; 95% confidence interval: 1.69-2.07; P <0.01). The instrumental variable analysis showed that an increased proportion of improved ADL was associated with early rehabilitation (risk difference: 2.8%; 95% confidence interval: 2.0-3.4%; P <0.001) and intensive rehabilitation (risk difference: 5.6%; 95% confidence interval: 4.6-6.6%; P <0.001). The present results suggested that early and intensive rehabilitation improved ADL during hospitalization in patients with ischemic stroke. © 2017 American Heart Association, Inc.

Short-Term Effect of Vermicompost Application on Biological Properties of an Alkaline Soil with High Lime Content from Mediterranean Region of Turkey

PubMed Central

Uz, Ilker; Tavali, Ismail Emrah

2014-01-01

This study was conducted to investigate direct short-term impact of vermicompost on some soil biological properties by monitoring changes after addition of vermicompost as compared to farmyard manure in an alkaline soil with high lime content from semiarid Mediterranean region of Turkey. For this purpose, mixtures of soil and organic fertilizers in different doses were incubated under greenhouse condition. Soil samples collected in regular intervals were analyzed for biological parameters including dehydrogenase, β-glucosidase, urease, alkaline phosphatase activities, and total number of aerobic mesophilic bacteria. Even though soil dehydrogenase activity appeared to be dose-independent based on overall evaluation, organic amendments were found to elevate dehydrogenase activity when sampling periods are evaluated individually. β-glucosidase, urease, alkaline phosphatase activity, and aerobic mesophilic bacterial numbers in vermicompost treatments fluctuated but remained significantly above the control. A slight but statistically significant difference was detected between organic amendments in terms of urease activity. Vermicompost appeared to more significantly increase bacterial number in soil. Clearly, vermicompost has a potential to be used as an alternative to farmyard manure to improve and maintain soil biological activity in alkaline calcareous soils from the Mediterranean region of Turkey. Further studies are needed to assess its full potential for these soils. PMID:25254238

Ventricular Cycle Length Characteristics Estimative of Prolonged RR Interval during Atrial Fibrillation

PubMed Central

CIACCIO, EDWARD J.; BIVIANO, ANGELO B.; GAMBHIR, ALOK; EINSTEIN, ANDREW J.; GARAN, HASAN

2014-01-01

Background When atrial fibrillation (AF) is incessant, imaging during a prolonged ventricular RR interval may improve image quality. It was hypothesized that long RR intervals could be predicted from preceding RR values. Methods From the PhysioNet database, electrocardiogram RR intervals were obtained from 74 persistent AF patients. An RR interval lengthened by at least 250 ms beyond the immediately preceding RR interval (termed T0 and T1, respectively) was considered prolonged. A two-parameter scatterplot was used to predict the occurrence of a prolonged interval T0. The scatterplot parameters were: (1) RR variability (RRv) estimated as the average second derivative from 10 previous pairs of RR differences, T13–T2, and (2) Tm–T1, the difference between Tm, the mean from T13 to T2, and T1. For each patient, scatterplots were constructed using preliminary data from the first hour. The ranges of parameters 1 and 2 were adjusted to maximize the proportion of prolonged RR intervals within range. These constraints were used for prediction of prolonged RR in test data collected during the second hour. Results The mean prolonged event was 1.0 seconds in duration. Actual prolonged events were identified with a mean positive predictive value (PPV) of 80% in the test set. PPV was >80% in 36 of 74 patients. An average of 10.8 prolonged RR intervals per 60 minutes was correctly identified. Conclusions A method was developed to predict prolonged RR intervals using two parameters and prior statistical sampling for each patient. This or similar methodology may help improve cardiac imaging in many longstanding persistent AF patients. PMID:23998759

Antigenotoxic properties of lactic acid bacteria in the S. typhimurium mutagenicity assay.

PubMed

Pool-Zobel, B L; Münzner, R; Holzapfel, W H

1993-01-01

A high percentage of human tumors is reported to be related to dietary habits. One way to improve the nutritional impact is to increase the intake of protective factors, such as inhibitors of DNA damage and other types of anticarcinogens. Specific strains of lactic acid bacteria used to ferment milk are promising candidates that may be antimutagenic and anticarcinogenic. We have studied the antimutagenicity of 10 isolated strains of beneficial lactic acid bacteria. Four types of fermented milk products were also studied for their protective properties. The effect of these bacteria on the yield of revertants induced by nitrosated beef extract was investigated in the Salmonella typhimurium mutagenicity assay. Eight of 10 isolated Lactobacillus strains reduced the yield of his+ revertants almost back to the levels of the untreated controls. Different fermented fresh yogurts containing viable bacteria (probably Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus or Lactobacillus acidophilus and Bifidobacteria) showed protective effects as well. The degree of suppressing revertants was independent of the yogurt's fat content. In contrast, yogurt products that had been heat treated were not inhibitory. The other fresh fermented milk products (e.g., buttermilk, kefir, and "Dickmilch") were not antimutagenic in this study. The results imply that some bacteria used in milk processing have an antimutagenic potential and that this property is specific for the bacterial strain.

A novel co-culture model of murine K12 osteosarcoma cells and S. aureus on common orthopedic implant materials: 'the race to the surface' studied in vitro.

PubMed

McConda, David B; Karnes, Jonathan M; Hamza, Therwa; Lindsey, Brock A

2016-07-01

Infection is a major cause of orthopedic implant failure. There are few studies assessing both tissue cell and bacterial adherence on common orthopedic implant materials in a co-culture environment. An in vitro co-culture model was created using K12 osteosarcoma cells and Staphylococcus aureus in a medium incubated over metal disks for 48 h. The results showed that, in the presence of S. aureus, there were fewer osteosarcoma cells attached to the disks for all substrata tested. There were significantly more osteosarcoma cells adhering to the cobalt chrome than the stainless steel and titanium disks. Overall, in the presence of osteosarcoma cells, there were more bacteria adhering to the disks for all the substrata tested, with significantly more bacteria adhering to the stainless steel disks compared to cobalt chrome and titanium disks. Scanning electron microscopy verified that osteosarcoma cells and bacteria were adherent to the metal disks after incubation for 48 h. Furthermore, the observation that more bacteria were in the co-culture than in the control sample suggests that the osteosarcoma cells serve as a nutrient source for the bacteria. Future models assessing the interaction of osteogenic cells with bacteria on a substratum would be improved if the model accounted for the role of the immune system in secondary bone healing.

Coupled effects of methane monooxygenase and nitrogen source on growth and poly-β-hydroxybutyrate (PHB) production of Methylosinus trichosporium OB3b.

PubMed

Zhang, Tingting; Zhou, Jiti; Wang, Xiaowei; Zhang, Yu

2017-02-01

The coupled effects of nitrogen source and methane monooxygenase (MMO) on the growth and poly-β-hydroxybutyrate (PHB) accumulation capacity of methanotrophs were explored. The ammonia-supplied methanotrophs expressing soluble MMO (sMMO) grew at the highest rate, while N 2 -fixing bacteria expressing particulate MMO (pMMO) grew at the lowest rate. Further study showed that more hydroxylamine and nitrite was formed by ammonia-supplied bacteria containing pMMO, which might cause their slightly lower growth rate. The highest PHB content (51.0%) was obtained under nitrogen-limiting conditions with the inoculation of nitrate-supplied bacteria containing pMMO. Ammonia-supplied bacteria also accumulated a higher content of PHB (45.2%) with the expression of pMMO, while N 2 -fixing bacteria containing pMMO only showed low PHB production capacity (32.1%). The maximal PHB contents of bacteria expressing sMMO were low, with no significant change under different nitrogen source conditions. The low MMO activity, low cell growth rate and low PHB production capacity of methanotrophs continuously cultivated with N 2 with the expression of pMMO were greatly improved in the cyclic NO 3 - N 2 cultivation regime, indicating that long-term deficiency of nitrogen sources was detrimental to the activity of methanotrophs expressing pMMO. Copyright © 2016. Published by Elsevier B.V.

Activation of multiple chemotherapeutic prodrugs by the natural enzymolome of tumour-localised probiotic bacteria.

PubMed

Lehouritis, Panos; Stanton, Michael; McCarthy, Florence O; Jeavons, Matthieu; Tangney, Mark

2016-01-28

Some chemotherapeutic drugs (prodrugs) require activation by an enzyme for efficacy. We and others have demonstrated the ability of probiotic bacteria to grow specifically within solid tumours following systemic administration, and we hypothesised that the natural enzymatic activity of these tumour-localised bacteria may be suitable for activation of certain such chemotherapeutic drugs. Several wild-type probiotic bacteria; Escherichia coli Nissle, Bifidobacterium breve, Lactococcus lactis and Lactobacillus species, were screened against a panel of popular prodrugs. All strains were capable of activating at least one prodrug. E. coli Nissle 1917 was selected for further studies because of its ability to activate numerous prodrugs and its resistance to prodrug toxicity. HPLC data confirmed biochemical transformation of prodrugs to their toxic counterparts. Further analysis demonstrated that different enzymes can complement prodrug activation, while simultaneous activation of multiple prodrugs (CB1954, 5-FC, AQ4N and Fludarabine phosphate) by E. coli was confirmed, resulting in significant efficacy improvement. Experiments in mice harbouring murine tumours validated in vitro findings, with significant reduction in tumour growth and increase in survival of mice treated with probiotic bacteria and a combination of prodrugs. These findings demonstrate the ability of probiotic bacteria, without the requirement for genetic modification, to enable high-level activation of multiple prodrugs specifically at the site of action. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of levan-type fructan on growth performance, nutrient digestibility, diarrhoea scores, faecal shedding of total lactic acid bacteria and coliform bacteria, and faecal gas emission in weaning pigs.

PubMed

Lei, Xin Jian; Kim, Yong Min; Park, Jae Hong; Baek, Dong Heon; Nyachoti, Charles Martin; Kim, In Ho

2018-03-01

The use of antibiotics as growth promoters in feed has been fully or partially banned in several countries. The objective of this study was to evaluate effects of levan-type fructan on growth performance, nutrient digestibility, faecal shedding of lactic acid bacteria and coliform bacteria, diarrhoea scores, and faecal gas emission in weaning pigs. A total of 144 weaning pigs [(Yorkshire × Landrace) × Duroc] were randomly allocated to four diets: corn-soybean meal-based diets supplemented with 0, 0.1, 0.5, or 1.0 g kg -1 levan-type fructan during this 42-day experiment. During days 0 to 21 and 0 to 42, average daily gain and average daily feed intake were linearly increased (P < 0.01) with increasing dietary levan-type fructan inclusion. The apparent total tract digestibility of dry matter, crude protein, and gross energy were linearly increased (P < 0.001) with increasing dietary levan-type fructan content. With increasing levels of levan-type fructan, faecal lactic acid bacteria counts were linearly increased (P = 0.001). The results indicate that dietary supplementation with increasing levan-type fructan enhanced growth performance, improved nutrient digestibility, and increased faecal lactic acid bacteria counts in weaning pigs linearly. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Military Applicability of Interval Training for Health and Performance.

PubMed

Gibala, Martin J; Gagnon, Patrick J; Nindl, Bradley C

2015-11-01

Militaries from around the globe have predominantly used endurance training as their primary mode of aerobic physical conditioning, with historical emphasis placed on the long distance run. In contrast to this traditional exercise approach to training, interval training is characterized by brief, intermittent bouts of intense exercise, separated by periods of lower intensity exercise or rest for recovery. Although hardly a novel concept, research over the past decade has shed new light on the potency of interval training to elicit physiological adaptations in a time-efficient manner. This work has largely focused on the benefits of low-volume interval training, which involves a relatively small total amount of exercise, as compared with the traditional high-volume approach to training historically favored by militaries. Studies that have directly compared interval and moderate-intensity continuous training have shown similar improvements in cardiorespiratory fitness and the capacity for aerobic energy metabolism, despite large differences in total exercise and training time commitment. Interval training can also be applied in a calisthenics manner to improve cardiorespiratory fitness and strength, and this approach could easily be incorporated into a military conditioning environment. Although interval training can elicit physiological changes in men and women, the potential for sex-specific adaptations in the adaptive response to interval training warrants further investigation. Additional work is needed to clarify adaptations occurring over the longer term; however, interval training deserves consideration from a military applicability standpoint as a time-efficient training strategy to enhance soldier health and performance. There is value for military leaders in identifying strategies that reduce the time required for exercise, but nonetheless provide an effective training stimulus.

Native plant growth promoting bacteria Bacillus thuringiensis and mixed or individual mycorrhizal species improved drought tolerance and oxidative metabolism in Lavandula dentata plants.

PubMed

Armada, E; Probanza, A; Roldán, A; Azcón, R

2016-03-15

This study evaluates the responses of Lavandula dentata under drought conditions to the inoculation with single autochthonous arbuscular mycorrhizal (AM) fungus (five fungal strains) or with their mixture and the effects of these inocula with a native Bacillus thuringiensis (endophytic bacteria). These microorganisms were drought tolerant and in general, increased plant growth and nutrition. Particularly, the AM fungal mixture and B. thuringiensis maximized plant biomass and compensated drought stress as values of antioxidant activities [superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase APX)] shown. The AMF-bacteria interactions highly reduced the plant oxidative damage of lipids [malondialdehyde (MDA)] and increased the mycorrhizal development (mainly arbuscular formation representative of symbiotic functionality). These microbial interactions explain the highest potential of dually inoculated plants to tolerate drought stress. B. thuringiensis "in vitro" under osmotic stress does not reduce its PGPB (plant growth promoting bacteria) abilities as indole acetic acid (IAA) and ACC deaminase production and phosphate solubilization indicating its capacity to improve plant growth under stress conditions. Each one of the autochthonous fungal strains maintained their particular interaction with B. thuringiensis reflecting the diversity, intrinsic abilities and inherent compatibility of these microorganisms. In general, autochthonous AM fungal species and particularly their mixture with B. thuringiensis demonstrated their potential for protecting plants against drought and helping plants to thrive in semiarid ecosystems. Copyright © 2015 Elsevier GmbH. All rights reserved.

Wheat Bran Enhances the Cytotoxicity of Immobilized Alcaligenes aquatilis F8 against Microcystis aeruginosa

PubMed Central

Sun, Pengfei; Lin, Hui; Wang, Guan; Zhang, Ximing; Zhang, Qichun; Zhao, Yuhua

2015-01-01

Algicidal bacteria offer a promising option for killing cyanobacteria. Therefore, a new Alcaligenes aquatilis strain F8 was isolated to control Microcystis aeruginosa in this study. The algicidal activity of strain F8 was dependent on the cell density of M. aeruginosa, and the maximal algicidal rate of the free bacterium reached 88.45% within 72 h. With a view to its application to the control of M. aeruginosa in the natural environment, strain F8 was immobilized in sodium alginate beads, but immobilization of the strain decreased its algicidal rate compared to that of the free bacterium. However, addition of wheat bran to the sodium alginate matrix used to immobilize strain F8 not only eliminated the adverse effects of immobilization on the bacteria but also resulted in an 8.83% higher algicidal rate of the immobilized than free bacteria. Exclusion and recovery methods were used to identify key ingredients of wheat bran and gain insight into the mechanism underlying the observed enhancement of algicidal activity. This analysis indicated that certain factors in wheat bran, including vitamins B1, B2, B9, and E were responsible for promoting bacterial growth and thereby improving the algicidal rate of immobilized strain F8. Our findings indicate that wheat bran is able to improve the algicidal efficiency of A. aquatilis strain F8 for killing M. aeruginosa and is a good source of not only carbon and nitrogen but also vitamins for bacteria. PMID:26295573

Impact of probiotic administration on the health and fecal microbiota of young calves: a meta-analysis of randomized controlled trials of lactic acid bacteria.

PubMed

Signorini, M L; Soto, L P; Zbrun, M V; Sequeira, G J; Rosmini, M R; Frizzo, L S

2012-08-01

Before weaning, dairy calves are susceptible to many pathogens which can affect their subsequent performance. The use of lactic acid bacteria (LAB) has been identified as a tool to maintain the intestinal microbial balance and to prevent the establishment of opportunistic pathogenic bacterial populations. However, a consensus has not been reached as to whether probiotics may be effective in reducing the prevalence of gastrointestinal diseases in young calves. The aim of this meta-analysis was to assess the effect of probiotics on diarrhea incidence and the intestinal microbial balance. LAB supplementation has been shown to exert a protective effect and to reduce the incidence of diarrhea (relative risk, RR=0.437, 95% confidence interval (CI) 0.251-0.761). In the subanalysis, this protective effect of the probiotics against diarrhea was observed only in trials that used whole milk (RR=0.154, 95% CI 0.079-0.301) and trials that used multistrain inocula (RR=0.415, 95% CI 0.227-0.759). Probiotics did not improve the fecal characteristics (standardized mean difference, SMD=-0.4904, 95% CI -1.011-0.035) and were unable to change the LAB:coliforms ratio (SMD=0.016, 95% CI -0.701-0.733). Probiotics showed a beneficial impact on the LAB:coliforms ratio in the subanalysis that included trials that used whole milk (SMD=0.780, 95% CI 0.141-1.418) and monostrain inocula (SMD=0.990, 95% CI 0.340-1.641). The probability of significant effects (probiotic positive effect) in a new study was >0.70 for diarrhea and fecal consistency. Whole milk feeding improved the action of the probiotic effect on the incidence of diarrhea and LAB:coliforms ratio. The probability to find significant effects in the diarrhea frequency and LAB:coliforms ratio was higher (P>0.85) if the new studies were conducted using whole milk to feed calves. This paper defines the guidelines to standardize the experimental designs of future trials. LAB can be used as growth promoters in calves instead of antibiotics to counteract the negative effects of their widespread use. Copyright © 2011 Elsevier Ltd. All rights reserved.

Interval Exercise Therapy for Type 2 Diabetes.

PubMed

Hamasaki, Hidetaka

2018-01-01

Regular exercise improves glycemic control and reduces cardiovascular risk and mortality in patients with type 2 diabetes. Continuous moderate- to high-intensity exercise has been recommended to manage type 2 diabetes; however, only approximately 30% of diabetic patients achieve the recommended levels of physical activity. The reasons for not engaging in regular exercise vary; however, one of the common reasons is lack of time. Recently, the effectiveness of shortduration interval exercise such as high-intensity interval training and interval walking has been observed. Thus, the author aimed to summarize the current knowledge and discuss recent literature regarding the effects of interval exercise therapy in type 2 diabetes. The author searched the English literature on interval training and type 2 diabetes using Pub- Med. A total of 8 studies met the criteria. Interval exercise is feasible and effective in obtaining glycemic control in patients with type 2 diabetes. It may also improve body composition, insulin sensitivity, aerobic capacity, and oxidative stress more effectively than continuous exercise. As a novel exercise therapy, interval training appears to be effective in managing type 2 diabetes. However, the safety and efficacy of this exercise modality in patients with progressed diabetic complications or a history of cardiovascular disease and in extremely older individuals remain unknown. Additionally, there is considerable heterogeneity in exercise interventions (intensity and duration) between clinical studies. Further studies are needed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

[Effect of high-intensity interval training on the reduction of glycosylated hemoglobin in type-2 diabetic adult patients].

PubMed

Aguilera Eguía, Raúl Alberto; Russell Guzmán, Javier Antonio; Soto Muñoz, Marcelo Enrique; Villegas González, Bastián Eduardo; Poblete Aro, Carlos Emilio; Ibacache Palma, Alejandro

2015-03-05

Type 2 diabetes mellitus is one of the major non-communicable chronic diseases in the world. Its prevalence in Chile is significant, and complications associated with this disease involve great costs, which is why prevention and treatment of this condition are essential. Physical exercise is an effective means for prevention and treatment of type 2 diabetes mellitus. The emergence of new forms of physical training, such as "high intensity interval training", presents novel therapeutic alternatives for patients and health care professionals. To assess the validity and applicability of the results regarding the effectiveness of high intensity interval training in reducing glycosylated hemoglobin in adult patients with type 2 diabetes mellitus and answer the following question: In subjects with type 2 diabetes, can the method of high intensity interval training compared to moderate intensity exercise decrease glycosylated hemoglobin? We performed a critical analysis of the article "Feasibility and preliminary effectiveness of high intensity interval training in type 2 diabetes". We found no significant differences in the amount of glycosylated hemoglobin between groups of high intensity interval training and moderate-intensity exercise upon completion of the study (p>0.05). In adult patients with type 2 diabetes mellitus, high intensity interval training does not significantly improve glycosylated hemoglobin levels. Despite this, the high intensity interval training method shows as much improvement in body composition and physical condition as the moderate intensity exercise program.

The effects of context and musical training on auditory temporal-interval discrimination.

PubMed

Banai, Karen; Fisher, Shirley; Ganot, Ron

2012-02-01

Non sensory factors such as stimulus context and musical experience are known to influence auditory frequency discrimination, but whether the context effect extends to auditory temporal processing remains unknown. Whether individual experiences such as musical training alter the context effect is also unknown. The goal of the present study was therefore to investigate the effects of stimulus context and musical experience on auditory temporal-interval discrimination. In experiment 1, temporal-interval discrimination was compared between fixed context conditions in which a single base temporal interval was presented repeatedly across all trials and variable context conditions in which one of two base intervals was randomly presented on each trial. Discrimination was significantly better in the fixed than in the variable context conditions. In experiment 2 temporal discrimination thresholds of musicians and non-musicians were compared across 3 conditions: a fixed context condition in which the target interval was presented repeatedly across trials, and two variable context conditions differing in the frequencies used for the tones marking the temporal intervals. Musicians outperformed non-musicians on all 3 conditions, but the effects of context were similar for the two groups. Overall, it appears that, like frequency discrimination, temporal-interval discrimination benefits from having a fixed reference. Musical experience, while improving performance, did not alter the context effect, suggesting that improved discrimination skills among musicians are probably not an outcome of more sensitive contextual facilitation or predictive coding mechanisms. Copyright © 2011 Elsevier B.V. All rights reserved.

Preparation of melt-spun antimicrobially modified LDH/polyolefin nanocomposite fibers.

PubMed

Kutlu, Burak; Schröttner, Percy; Leuteritz, Andreas; Boldt, Regine; Jacobs, Enno; Heinrich, Gert

2014-08-01

Layered double hydroxide (LDH) was synthesized and organically modified with camphorsulfonic acid (CSA) and ciprofloxacin. The thermal stability of CSA was improved remarkably under LDH shielding. A minimal inhibitory concentration of free CSA against tested bacteria was determined in order to define the essential quantity in LDH modification. The modified LDHs were melt-compounded with high density polyethylene and the prepared nanocomposites were further melt-spun using a piston-type spinning device. The melt-spun fibers were tested for their antimicrobial activity against Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Enterobacter cloacae, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. CSA integrated fibers show susceptibility against Gram-positive bacteria and ciprofloxacin integrated fibers showed activity against both Gram-positive and Gram-negative bacteria. Copyright © 2014 Elsevier B.V. All rights reserved.

Marshall Barber and the century of microinjection: from cloning of bacteria to cloning of everything.

PubMed

Korzh, Vladimir; Strähle, Uwe

2002-08-01

A hundred years ago, Dr. Marshall A. Barber proposed a new technique - the microinjection technique. He developed this method initially to clone bacteria and to confirm the germ theory of Koch and Pasteur. Later on, he refined his approach and was able to manipulate nuclei in protozoa and to implant bacteria into plant cells. Continuous improvement and adaptation of this method to new applications dramatically changed experimental embryology and cytology and led to the formation of several new scientific disciplines including animal cloning as one of its latest applications. Interestingly, microinjection originated as a method at the crossroad of bacteriology and plant biology, demonstrating once again the unforeseen impact that basic research in an unrelated field can have on the development of entirely different disciplines.

Microbial Community Structures and Dynamics in the O3/BAC Drinking Water Treatment Process

PubMed Central

Tian, Jian; Lu, Jun; Zhang, Yu; Li, Jian-Cheng; Sun, Li-Chen; Hu, Zhang-Li

2014-01-01

Effectiveness of drinking water treatment, in particular pathogen control during the water treatment process, is always a major public health concern. In this investigation, the application of PCR-DGGE technology to the analysis of microbial community structures and dynamics in the drinking water treatment process revealed several dominant microbial populations including: α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Bacteroidetes, Actinobacteria Firmicutes and Cyanobacteria. α-Proteobacteria and β-Proteobacteria were the dominant bacteria during the whole process. Bacteroidetes and Firmicutes were the dominant bacteria before and after treatment, respectively. Firmicutes showed season-dependent changes in population dynamics. Importantly, γ-Proteobacteria, which is a class of medically important bacteria, was well controlled by the O3/biological activated carbon (BAC) treatment, resulting in improved effluent water bio-safety. PMID:24937529

Design requirements for ERD in diffusion-dominated media: how do injection interval, bioactive zones and reaction kinetics affect remediation performance?

NASA Astrophysics Data System (ADS)

Chambon, J.; Lemming, G.; Manoli, G.; Broholm, M. M.; Bjerg, P.; Binning, P. J.

2011-12-01

Enhanced Reductive Dechlorination (ERD) has been successfully used in high permeability media, such as sand aquifers, and is considered to be a promising technology for low permeability settings. Pilot and full-scale applications of ERD at several sites in Denmark have shown that the main challenge is to get contact between the injected bacteria and electron donor and the contaminants trapped in the low-permeability matrix. Sampling of intact cores from the low-permeability matrix has shown that the bioactive zones (where degradation occurs) are limited in the matrix, due to the slow diffusion transport processes, and this affects the timeframes for the remediation. Due to the limited ERD applications and the complex transport and reactive processes occurring in low-permeability media, design guidelines are currently not available for ERD in such settings, and remediation performance assessments are limited. The objective of this study is to combine existing knowledge from several sites with numerical modeling to assess the effect of the injection interval, development of bioactive zones and reaction kinetics on the remediation efficiency for ERD in diffusion-dominated media. A numerical model is developed to simulate ERD at a contaminated site, where the source area (mainly TCE) is located in a clayey till with fractures and interbedded sand lenses. Such contaminated sites are common in North America and Europe. Hydro-geological characterization provided information on geological heterogeneities and hydraulic parameters, which are relevant for clay till sites in general. The numerical model couples flow and transport in the fracture network and low-permeability matrix. Sequential degradation of TCE to ethene is modeled using Monod kinetics, and the kinetic parameters are obtained from laboratory experiments. The influence of the reaction kinetics on remediation efficiency is assessed by varying the biomass concentration of the specific degraders. The injected reactants (donor and bacteria) are assumed to spread in horizontal injection zones of various widths, depending on the development of bioactive zones. These injection zones are spaced at various intervals over depth, corresponding to the injection interval chosen. The results from the numerical model show that remediation timeframes can be reduced significantly by using closely spaced injection intervals and by ensuring the efficient spreading of the reactants into the clay till matrix. In contrast the reaction kinetics affect mass removal only up to a point where diffusive transport becomes limiting. Based on these results, guidelines on when ERD can be an effective remediation strategy in practice are provided. These take the form of dimensionless groupings (such as the Damkohler number), which combine site specific (physical and biogeochemical) and design parameters, and graphs showing how the main parameters affect remediation timeframes. Finally it is shown how model results can be used as input to other decision making tools such as life cycle assessment to guide remedial choices.

Phytosynthetic bacteria (PSB) as a water quality improvement mechanism in saline-alkali wetland ponds.

PubMed

Liu, Fu-jun; Hu, Weng-Ying; Li, Quan-Yi

2002-07-01

The efficiency of phytosynthetic bacteria (PSB) to improve the water quality in saline-alkali ponds was studied, the result showed that (1) PSB application could increase the content of DO, NO3-(-)N and effective phosphorus (EP) in ponds; (2) the changes of COD were not evident, just effective in later period after PSB application; (3) PSB application could decrease the contents of NH4-(-)N (NH3-N), NO2-(-)N; (4) PSB application could improve the structure of the effective nitrogen (EN) and EP, stimulate the growth of phytoplankton, and increase primary productivity, and finally increase the commercial profits of ponds because of the increase of EP and the decrease of EN contents; (5) the effect-exerting speed of PSB was slower, but the effect-sustaining time was longer; (6) the appropriate concentration of PSB application in saline-alkali wetland ponds was 10 x 10(-6) mg/L, one-time effective period was more than 15 days. So PSB was an efficient water quality improver in saline-alkali ponds.

Compressive Sensing of Foot Gait Signals and Its Application for the Estimation of Clinically Relevant Time Series.

PubMed

Pant, Jeevan K; Krishnan, Sridhar

2016-07-01

A new signal reconstruction algorithm for compressive sensing based on the minimization of a pseudonorm which promotes block-sparse structure on the first-order difference of the signal is proposed. Involved optimization is carried out by using a sequential version of Fletcher-Reeves' conjugate-gradient algorithm, and the line search is based on Banach's fixed-point theorem. The algorithm is suitable for the reconstruction of foot gait signals which admit block-sparse structure on the first-order difference. An additional algorithm for the estimation of stride-interval, swing-interval, and stance-interval time series from the reconstructed foot gait signals is also proposed. This algorithm is based on finding zero crossing indices of the foot gait signal and using the resulting indices for the computation of time series. Extensive simulation results demonstrate that the proposed signal reconstruction algorithm yields improved signal-to-noise ratio and requires significantly reduced computational effort relative to several competing algorithms over a wide range of compression ratio. For a compression ratio in the range from 88% to 94%, the proposed algorithm is found to offer improved accuracy for the estimation of clinically relevant time-series parameters, namely, the mean value, variance, and spectral index of stride-interval, stance-interval, and swing-interval time series, relative to its nearest competitor algorithm. The improvement in performance for compression ratio as high as 94% indicates that the proposed algorithms would be useful for designing compressive sensing-based systems for long-term telemonitoring of human gait signals.

Scale Dependence of Oak Woodland Historical Fire Intervals: Contrasting the Barrens of Tennessee and Cross Timbers of Oklahoma, USA

Treesearch

Michael C. Stambaugh; Richard P. Guyette; Joseph M. Marschall; Daniel C. Dey

2016-01-01

Characterization of scale dependence of fire intervals could inform interpretations of fire history and improve fire prescriptions that aim to mimic historical fire regime conditions. We quantified the temporal variability in fire regimes and described the spatial dependence of fire intervals through the analysis of multi-century fire scar records (8 study sites, 332...

Refinement of regression models to estimate real-time concentrations of contaminants in the Menomonee River drainage basin, southeast Wisconsin, 2008-11

USGS Publications Warehouse

Baldwin, Austin K.; Robertson, Dale M.; Saad, David A.; Magruder, Christopher

2013-01-01

In 2008, the U.S. Geological Survey and the Milwaukee Metropolitan Sewerage District initiated a study to develop regression models to estimate real-time concentrations and loads of chloride, suspended solids, phosphorus, and bacteria in streams near Milwaukee, Wisconsin. To collect monitoring data for calibration of models, water-quality sensors and automated samplers were installed at six sites in the Menomonee River drainage basin. The sensors continuously measured four potential explanatory variables: water temperature, specific conductance, dissolved oxygen, and turbidity. Discrete water-quality samples were collected and analyzed for five response variables: chloride, total suspended solids, total phosphorus, Escherichia coli bacteria, and fecal coliform bacteria. Using the first year of data, regression models were developed to continuously estimate the response variables on the basis of the continuously measured explanatory variables. Those models were published in a previous report. In this report, those models are refined using 2 years of additional data, and the relative improvement in model predictability is discussed. In addition, a set of regression models is presented for a new site in the Menomonee River Basin, Underwood Creek at Wauwatosa. The refined models use the same explanatory variables as the original models. The chloride models all used specific conductance as the explanatory variable, except for the model for the Little Menomonee River near Freistadt, which used both specific conductance and turbidity. Total suspended solids and total phosphorus models used turbidity as the only explanatory variable, and bacteria models used water temperature and turbidity as explanatory variables. An analysis of covariance (ANCOVA), used to compare the coefficients in the original models to those in the refined models calibrated using all of the data, showed that only 3 of the 25 original models changed significantly. Root-mean-squared errors (RMSEs) calculated for both the original and refined models using the entire dataset showed a median improvement in RMSE of 2.1 percent, with a range of 0.0–13.9 percent. Therefore most of the original models did almost as well at estimating concentrations during the validation period (October 2009–September 2011) as the refined models, which were calibrated using those data. Application of these refined models can produce continuously estimated concentrations of chloride, total suspended solids, total phosphorus, E. coli bacteria, and fecal coliform bacteria that may assist managers in quantifying the effects of land-use changes and improvement projects, establish total maximum daily loads, and enable better informed decision making in the future.

Engineering solutions to improve the removal of fecal indicator bacteria by bioinfiltration systems during intermittent flow of stormwater.

PubMed

Mohanty, Sanjay K; Torkelson, Andrew A; Dodd, Hanna; Nelson, Kara L; Boehm, Alexandria B

2013-10-01

Bioinfiltration systems facilitate the infiltration of urban stormwater into soil and reduce high flow events and flooding. Stormwater carries a myriad of pollutants including fecal indicator bacteria (FIB). Significant knowledge gaps exist about the ability of bioinfiltration systems to remove and retain FIB. The present study investigates the ability of model, simplified bioinfiltration systems containing quartz sand and iron oxide-coated quartz sand (IOCS) to remove two FIB (Enterococcus faecalis and Escherichia coli) suspended in synthetic stormwater with and without natural organic matter (NOM) as well as the potential for accumulated FIB to be remobilized during intermittent flow. The experiments were conducted in two phases: (1) the saturated columns packed with either sand or IOCS were contaminated by injecting stormwater with bacteria followed by injection of sterile stormwater and (2) the contaminated columns were subjected to intermittent infiltration of sterile stormwater preceded by a pause during which columns were either kept saturated or drained by gravity. During intermittent flow, fewer bacteria were released from the saturated column compared to the column drained by gravity: 12% of attached E. coli and 3% of attached Ent. faecalis were mobilized from the drained sand column compared to 3% of attached E. coli and 2% attached Ent. faecalis mobilized from the saturated sand column. Dry and wet cycles introduce moving air-water interfaces that can scour bacteria from grain surfaces. During intermittent flows, less than 0.2% of attached bacteria were mobilized from IOCS, which bound both bacteria irreversibly in the absence of NOM. Addition of NOM, however, increased bacterial mobilization from IOCS: 50% of attached E. coli and 8% of attached Ent. faecalis were released from IOCS columns during draining and rewetting. Results indicate that using geomedia such as IOCS that promote irreversible attachment of bacteria, and maintaining saturated condition, could minimize the mobilization of previous attached bacteria from bioinfiltration systems, although NOM may significantly decrease these benefits.

Revisiting the cape cod bacteria injection experiment using a stochastic modeling approach

USGS Publications Warehouse

Maxwell, R.M.; Welty, C.; Harvey, R.W.

2007-01-01

Bromide and resting-cell bacteria tracer tests conducted in a sandy aquifer at the U.S. Geological Survey Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach. Bacteria transport was coupled to colloid filtration theory through functional dependence of local-scale colloid transport parameters upon hydraulic conductivity and seepage velocity in a stochastic advection - dispersion/attachment - detachment model. Geostatistical information on the hydraulic conductivity (K) field that was unavailable at the time of the original test was utilized as input. Using geostatistical parameters, a groundwater flow and particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data. An optimization routine was employed over 100 realizations to adjust the mean and variance ofthe natural-logarithm of hydraulic conductivity (InK) field to achieve best fit of a simulated, average bromide breakthrough curve. A stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of mean bacteria breakthrough were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech (Environ. Sci. Technol. 2004, 38, 529-536) correlation equation for estimating single collector efficiency were compared to those using the older Rajagopalan and Tien (AIChE J. 1976, 22, 523-533) model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions. Simulations using a distribution of bacterial cell diameters available from original field notes yielded a slight improvement in the model and data agreement compared to simulations using an average bacterial diameter. The stochastic approach based on estimates of local-scale parameters for the bacteria-transport process reasonably captured the mean bacteria transport behavior and calculated an envelope of uncertainty that bracketed the observations in most simulation cases. ?? 2007 American Chemical Society.

The impact of labor-saving technology on first birth intervals in rural Ethiopia.

PubMed

Gibson, Mhairi; Mace, Ruth

2002-02-01

Across the developing world labor-saving technologies introduce considerable savings in the time and energy that women allocate to work. Hormonal studies on natural fertility populations indicate that such a reduction in energetic expenditure (rather than improved nutritional status alone) can lead to increased ovarian function. Other qualitative studies have highlighted a link between labor-saving technology and behavioral changes affecting subsequent age at marriage, which may affect fertility. This biodemographic study was designed to investigate whether these physiological and behavioral changes affect fertility at a population level by focusing on a recent water development scheme in Southern Ethiopia. The demographic consequences of a reduction in women's workload following the installation of water points, specifically the variation in length of first birth interval (time lapsed between marriage and first birth), are investigated. First birth interval length is closely associated with lifetime fertility in populations that do not practice contraception, longer intervals being associated with lower fertility. Using life tables and multivariate hazard modeling techniques a number of significant predictors of first birth interval length are identified. Covariates such as age at marriage, season of marriage, village ecology, and access to improved water supply have significant effects on variation in first birth intervals. When entered into models as a time-varying covariate, access to a water tap stand is associated with an immediate reduction in length of first birth intervals.

Identification of Some of the Major Groups of Bacteria in Efficient and Nonefficient Biological Phosphorus Removal Activated Sludge Systems

PubMed Central

Bond, Philip L.; Erhart, Robert; Wagner, Michael; Keller, Jürg; Blackall, Linda L.

1999-01-01

To investigate the bacteria that are important to phosphorus (P) removal in activated sludge, microbial populations were analyzed during the operation of a laboratory-scale reactor with various P removal performances. The bacterial population structure, analyzed by fluorescence in situ hybridization (FISH) with oligonucleotides probes complementary to regions of the 16S and 23S rRNAs, was associated with the P removal performance of the reactor. At one stage of the reactor operation, chemical characterization revealed that extremely poor P removal was occurring. However, like in typical P-removing sludges, complete anaerobic uptake of the carbon substrate occurred. Bacteria inhibiting P removal overwhelmed the reactor, and according to FISH, bacteria of the β subclass of the class Proteobacteria other than β-1 or β-2 were dominant in the sludge (58% of the population). Changes made to the operation of the reactor led to the development of a biomass population with an extremely good P removal capacity. The biochemical transformations observed in this sludge were characteristic of typical P-removing activated sludge. The microbial population analysis of the P-removing sludge indicated that bacteria of the β-2 subclass of the class Proteobacteria and actinobacteria were dominant (55 and 35%, respectively), therefore implicating bacteria from these groups in high-performance P removal. The changes in operation that led to the improved performance of the reactor included allowing the pH to rise during the anaerobic period, which promoted anaerobic phosphate release and possibly caused selection against non-phosphate-removing bacteria. PMID:10473419

Outer membrane vesicles as platform vaccine technology

PubMed Central

Stork, Michiel; van der Ley, Peter

2015-01-01

Abstract Outer membrane vesicles (OMVs) are released spontaneously during growth by many Gram‐negative bacteria. They present a range of surface antigens in a native conformation and have natural properties like immunogenicity, self‐adjuvation and uptake by immune cells which make them attractive for application as vaccines against pathogenic bacteria. In particular with Neisseria meningitidis, they have been investigated extensively and an OMV‐containing meningococcal vaccine has recently been approved by regulatory agencies. Genetic engineering of the OMV‐producing bacteria can be used to improve and expand their usefulness as vaccines. Recent work on meningitis B vaccines shows that OMVs can be modified, such as for lipopolysaccharide reactogenicity, to yield an OMV product that is safe and effective. The overexpression of crucial antigens or simultaneous expression of multiple antigenic variants as well as the expression of heterologous antigens enable expansion of their range of applications. In addition, modifications may increase the yield of OMV production and can be combined with specific production processes to obtain high amounts of well‐defined, stable and uniform OMV particle vaccine products. Further improvement can facilitate the development of OMVs as platform vaccine product for multiple applications. PMID:26912077

Metabolic Engineering for Probiotics and their Genome-Wide Expression Profiling.

PubMed

Yadav, Ruby; Singh, Puneet K; Shukla, Pratyoosh

2018-01-01

Probiotic supplements in food industry have attracted a lot of attention and shown a remarkable growth in this field. Metabolic engineering (ME) approaches enable understanding their mechanism of action and increases possibility of designing probiotic strains with desired functions. Probiotic microorganisms generally referred as industrially important lactic acid bacteria (LAB) which are involved in fermenting dairy products, food, beverages and produces lactic acid as final product. A number of illustrations of metabolic engineering approaches in industrial probiotic bacteria have been described in this review including transcriptomic studies of Lactobacillus reuteri and improvement in exopolysaccharide (EPS) biosynthesis yield in Lactobacillus casei LC2W. This review summaries various metabolic engineering approaches for exploring metabolic pathways. These approaches enable evaluation of cellular metabolic state and effective editing of microbial genome or introduction of novel enzymes to redirect the carbon fluxes. In addition, various system biology tools such as in silico design commonly used for improving strain performance is also discussed. Finally, we discuss the integration of metabolic engineering and genome profiling which offers a new way to explore metabolic interactions, fluxomics and probiogenomics using probiotic bacteria like Bifidobacterium spp and Lactobacillus spp. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Machine Reading for Extraction of Bacteria and Habitat Taxonomies

PubMed Central

Kordjamshidi, Parisa; Massa, Wouter; Provoost, Thomas; Moens, Marie-Francine

2015-01-01

There is a vast amount of scientific literature available from various resources such as the internet. Automating the extraction of knowledge from these resources is very helpful for biologists to easily access this information. This paper presents a system to extract the bacteria and their habitats, as well as the relations between them. We investigate to what extent current techniques are suited for this task and test a variety of models in this regard. We detect entities in a biological text and map the habitats into a given taxonomy. Our model uses a linear chain Conditional Random Field (CRF). For the prediction of relations between the entities, a model based on logistic regression is built. Designing a system upon these techniques, we explore several improvements for both the generation and selection of good candidates. One contribution to this lies in the extended exibility of our ontology mapper that uses an advanced boundary detection and assigns the taxonomy elements to the detected habitats. Furthermore, we discover value in the combination of several distinct candidate generation rules. Using these techniques, we show results that are significantly improving upon the state of art for the BioNLP Bacteria Biotopes task. PMID:27077141

A role for IL-22 in the relationship between intestinal helminths, gut microbiota and mucosal immunity.

PubMed

Leung, Jacqueline M; Loke, P'ng

2013-03-01

The intestinal tract is home to nematodes as well as commensal bacteria (microbiota), which have coevolved with the mammalian host. The mucosal immune system must balance between an appropriate response to dangerous pathogens and an inappropriate response to commensal microbiota that may breach the epithelial barrier, in order to maintain intestinal homeostasis. IL-22 has been shown to play a critical role in maintaining barrier homeostasis against intestinal pathogens and commensal bacteria. Here we review the advances in our understanding of the role of IL-22 in helminth infections, as well as in response to commensal and pathogenic bacteria of the intestinal tract. We then consider the relationship between intestinal helminths and gut microbiota and hypothesize that this relationship may explain how helminths may improve symptoms of inflammatory bowel diseases. We propose that by inducing an immune response that includes IL-22, intestinal helminths may enhance the mucosal barrier function of the intestinal epithelium. This may restore the mucosal microbiota populations from dysbiosis associated with colitis and improve intestinal homeostasis. Copyright © 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Potent antimicrobial and antibiofilm activities of bacteriogenically synthesized gold-silver nanoparticles against pathogenic bacteria and their physiochemical characterizations.

PubMed

Ramasamy, Mohankandhasamy; Lee, Jin-Hyung; Lee, Jintae

2016-09-01

The objective of this study was to develop a bimetallic nanoparticle with enhanced antibacterial activity that would improve the therapeutic efficacy against bacterial biofilms. Bimetallic gold-silver nanoparticles were bacteriogenically synthesized using γ-proteobacterium, Shewanella oneidensis MR-1. The antibacterial activities of gold-silver nanoparticles were assessed on the planktonic and biofilm phases of individual and mixed multi-cultures of pathogenic Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive bacteria (Enterococcus faecalis and Staphylococcus aureus), respectively. The minimum inhibitory concentration of gold-silver nanoparticles was 30-50 µM than that of other nanoparticles (>100 µM) for the tested bacteria. Interestingly, gold-silver nanoparticles were more effective in inhibiting bacterial biofilm formation at 10 µM concentration. Both scanning and transmission electron microscopy results further accounted the impact of gold-silver nanoparticles on biocompatibility and bactericidal effect that the small size and bio-organic materials covering on gold-silver nanoparticles improves the internalization and thus caused bacterial inactivation. Thus, bacteriogenically synthesized gold-silver nanoparticles appear to be a promising nanoantibiotic for overcoming the bacterial resistance in the established bacterial biofilms. © The Author(s) 2016.

High-Intensity Interval Training for Severe Left Ventricular Dysfunction Treated with Left Ventricular Assist Device.

PubMed

Ugata, Yusuke; Wada, Hiroshi; Sakakura, Kenichi; Ibe, Tatsuro; Ito, Miyuki; Ikeda, Nahoko; Fujita, Hideo; Momomura, Shin-Ichi

2018-01-27

Aerobic training based on anaerobic threshold (AT) is well-known to improve cardiac function, exercise capacity, and long-term outcomes of patients with heart failure. Recent reports suggested that high-intensity interval training (HIIT) for patients with cardiovascular disease may improve cardiopulmonary exercise capacity. We present a 61-year-old male patient of severe left ventricular dysfunction with left ventricular assisted device (LVAD). Following HIIT for 8 weeks, exercise capacity and muscle strength have improved without worsening left ventricular function. Our case showed the possibility that HIIT was feasible and effective even in patients with LVAD.

Some low homogenization pressures improve certain probiotic characteristics of yogurt culture bacteria and Lactobacillus acidophilus LA-K.

PubMed

Muramalla, T; Aryana, K J

2011-08-01

Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus salivarius ssp. thermophilus, and Lactobacillus acidophilus are dairy cultures widely used in the manufacture of cultured dairy products. Commonly used homogenization pressures in the dairy industry are 13.80 MPa or less. It is not known whether low homogenization pressures can stimulate bacteria to improve their probiotic characteristics. Objectives were to determine the effect of homogenization at 0, 3.45, 6.90, 10.34, and 13.80 MPa on acid tolerance, bile tolerance, protease activity, and growth of L. delbrueckii ssp. bulgaricus LB-12, S. salivarius ssp. thermophilus ST-M5, and L. acidophilus LA-K. The cultures were individually inoculated in cool autoclaved skim milk (4°C) and homogenized for 5 continuous passes. Growth and bile tolerance of samples were determined hourly for 10h of incubation. Acid tolerance was determined every 20 min for 120 min of incubation. Protease activity was determined at 0, 12, and 24h of incubation. All homogenization pressures studied improved acid tolerance of L. delbrueckii ssp. bulgaricus LB-12 but had no beneficial effect on protease activity and had negative effects on growth and bile tolerance. A pressure of 6.90 MPa improved acid tolerance, bile tolerance, and protease activity of S. salivarius ssp. thermophilus ST-M5, but none of the homogenization pressures studied had an effect on its growth. Homogenization pressures of 13.80 and 6.90 MPa improved acid tolerance and bile tolerance, respectively, of L. acidophilus LA-K but had no effect on protease activity and its growth. Some low homogenization pressures positively influenced some characteristics of yogurt culture bacteria and L. acidophilus LA-K. Culture pretreatment with some low homogenization pressures can be recommended for improvement of certain probiotic characteristics. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Elimination of Escherichia coli and Salmonella in Clam by Using Zeolite in a Station of Depuration.

PubMed

Gdoura, Morsi; Sellami, Hanen; Khannous, Lamia; Ketata, Najib; Neila, Idriss Ben; Traore, Al Ibrahim; Chekir, Zouhair; Gdoura, Radhouane

2017-09-01

  The application of natural zeolite for water and wastewater treatment has been carried out and is still a promising technique in environmental cleaning processes. Natural zeolite can be used to improve the purification process of clams (Ruditapes decussatus). Thus, our study aimed at improving the clam purification system in order to reduce Escherichia coli and eliminate Salmonella in samples artificially contaminated with this bacterium using a natural zeolite to replace the biological filter. The results showed that zeolite used in a depuration system improved the clam purification process. Moreover, natural zeolite exhibited high performance in the adsorption of bacteria and allowed to reduce the Escherichia coli abundance in 24 h, thus ensuring purified clams conformity with the ISO 16649-3 standard. These results indicate the beneficial effects of using zeolite in the adsorption of bacteria and the reduction in the abundance of Escherichia coli and set the Salmonella from marine organisms.

Progressive Colonization of Bacteria and Degradation of Rice Straw in the Rumen by Illumina Sequencing

PubMed Central

Cheng, Yanfen; Wang, Ying; Li, Yuanfei; Zhang, Yipeng; Liu, Tianyi; Wang, Yu; Sharpton, Thomas J.; Zhu, Weiyun

2017-01-01

The aim of this study was to improve the utilization of rice straw as forage in ruminants by investigating the degradation pattern of rice straw in the dairy cow rumen. Ground up rice straw was incubated in situ in the rumens of three Holstein cows over a period of 72 h. The rumen fluid at 0 h and the rice straw at 0.5, 1, 2, 4, 6, 12, 24, 48, and 72 h were collected for analysis of the bacterial community and the degradation of the rice straw. The bacterial community and the carbohydrate-active enzymes in the rumen fluid were analyzed by metagenomics. The diversity of bacteria loosely and tightly attached to the rice straw was investigated by scanning electron microscopy and Miseq sequencing of 16S rRNA genes. The predominant genus in the rumen fluid was Prevotella, followed by Bacteroides, Butyrivibrio, unclassified Desulfobulbaceae, Desulfovibrio, and unclassified Sphingobacteriaceae. The main enzymes were members of the glycosyl hydrolase family, divided into four categories (cellulases, hemicellulases, debranching enzymes, and oligosaccharide-degrading enzymes), with oligosaccharide-degrading enzymes being the most abundant. No significant degradation of rice straw was observed between 0.5 and 6 h, whereas the rice straw was rapidly degraded between 6 and 24 h. The degradation then gradually slowed between 24 and 72 h. A high proportion of unclassified bacteria were attached to the rice straw and that Prevotella, Ruminococcus, and Butyrivibrio were the predominant classified genera in the loosely and tightly attached fractions. The composition of the loosely attached bacterial community remained consistent throughout the incubation, whereas a significant shift in composition was observed in the tightly attached bacterial community after 6 h of incubation. This shift resulted in a significant reduction in numbers of Bacteroidetes and a significant increase in numbers of Firmicutes. In conclusion, the degradation pattern of rice straw in the dairy cow rumen indicates a strong contribution by tightly attached bacteria, especially after 6 h incubation, but most of these bacteria were not taxonomically characterized. Thus, these bacteria should be further identified and subjected to functional analysis to improve the utilization of crop residues in ruminants. PMID:29163444

A randomized clinical trial with two doses of an enteral diabetes-specific suplements in elderly patients with diabetes mellitus type 2.

PubMed

de Luis, D A; Izaola, O; de la Fuente, B; Terroba, M C; Cuellar, L; Cabezas, G

2013-06-01

The aim of our study was to investigate whether two different daily doses of a high monounsaturated fatty acid (MUFA) specific diabetes enteral formula could improve nutritional variables as well as metabolic parameters. We conducted a randomized, open-label, multicenter, parallel group study. 27 patients with diabetes mellitus type 2 with recent weight loss were randomized to one of two study groups: group 1 (two cans per day) and group 2 (three cans per day) for a ten week period. A significative decrease of HbA1c was detected in both groups. The decrease 0.98% (confidence interval 95% 0.19-1.88) was higher in group 2 than group 1 0.60% (confidence interval 95% 0.14-1.04). A significant increase of weight, body mass index, fat mass, albumin, prealbumin and transferrin was observed in both groups without statistical differences in this improvement between both groups. The increase of weight 4.59kg (confidence interval 95% 1.71-9.49) was higher in group 2 than group 1 1.46% (confidence interval 95% 0.39-2.54). Gastrointestinal tolerance (diarrhea episodes) with both formulas was good, without statistical differences (7.60% vs 7.14%: ns). A high monounsaturated fatty acid diabetes-specific supplement improved HbA1c and nutritional status. These improvements were higher with three supplements than with two per day.

Improved adjoin-list for quality-guided phase unwrapping based on red-black trees

NASA Astrophysics Data System (ADS)

Cruz-Santos, William; López-García, Lourdes; Rueda-Paz, Juvenal; Redondo-Galvan, Arturo

2016-08-01

The quality-guide phase unwrapping is an important technique that is based on quality maps which guide the unwrapping process. The efficiency of this technique depends in the adjoin-list data structure implementation. There exists several proposals that improve the adjoin-list; Ming Zhao et. al. proposed an Indexed Interwoven Linked List (I2L2) that is based on dividing the quality values into intervals of equal size and inserting in a linked list those pixels with quality values within a certain interval. Ming Zhao and Qian Kemao proposed an improved I2L2 replacing each linked list in each interval by a heap data structure, which allows efficient procedures for insertion and deletion. In this paper, we propose an improved I2L2 which uses Red-Black trees (RBT) data structures for each interval. Our proposal has as main goal to avoid the unbalanced properties of the head and thus, reducing the time complexity of insertion. In order to maintain the same efficiency of the heap when deleting an element, we provide an efficient way to remove the pixel with the highest quality value in the RBT using a pointer to the rightmost element in the tree. We also provide a new partition strategy of the phase values that is based on a density criterion. Experimental results applied to phase shifting profilometry are shown for large images.

Recent Advances in Root Canal Disinfection: A Review

PubMed Central

Mohammadi, Zahed; Jafarzadeh, Hamid; Shalavi, Sousan; Palazzi, Flavio

2017-01-01

The microbial biofilm is an important factor for human infection. Finding effective antimicrobial strategies should be considered for decreasing antimicrobial resistance and controlling the infectious diseases. Treatment of infected canal systems may not be able to remove all bacteria and so bacterial persistence after treatment may occur. Application of antibacterial nanoparticles may be a potential strategy to improve the elimination of bacteria from the canal. Furthermore, mechanism of action and applications of photodynamic therapy and Photon-induced photoacoustic streaming (PIPS) and GentleWave system was reviewed. PMID:29225632

Estimating reliable paediatric reference intervals in clinical chemistry and haematology.

PubMed

Ridefelt, Peter; Hellberg, Dan; Aldrimer, Mattias; Gustafsson, Jan

2014-01-01

Very few high-quality studies on paediatric reference intervals for general clinical chemistry and haematology analytes have been performed. Three recent prospective community-based projects utilising blood samples from healthy children in Sweden, Denmark and Canada have substantially improved the situation. The present review summarises current reference interval studies for common clinical chemistry and haematology analyses. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Influence of Pacing by Periodic Auditory Stimuli on Movement Continuation: Comparison with Self-regulated Periodic Movement

PubMed Central

Ito, Masanori; Kado, Naoki; Suzuki, Toshiaki; Ando, Hiroshi

2013-01-01

[Purpose] The purpose of this study was to investigate the influence of external pacing with periodic auditory stimuli on the control of periodic movement. [Subjects and Methods] Eighteen healthy subjects performed self-paced, synchronization-continuation, and syncopation-continuation tapping. Inter-onset intervals were 1,000, 2,000 and 5,000 ms. The variability of inter-tap intervals was compared between the different pacing conditions and between self-paced tapping and each continuation phase. [Results] There were no significant differences in the mean and standard deviation of the inter-tap interval between pacing conditions. For the 1,000 and 5,000 ms tasks, there were significant differences in the mean inter-tap interval following auditory pacing compared with self-pacing. For the 2,000 ms syncopation condition and 5,000 ms task, there were significant differences from self-pacing in the standard deviation of the inter-tap interval following auditory pacing. [Conclusion] These results suggest that the accuracy of periodic movement with intervals of 1,000 and 5,000 ms can be improved by the use of auditory pacing. However, the consistency of periodic movement is mainly dependent on the inherent skill of the individual; thus, improvement of consistency based on pacing is unlikely. PMID:24259932

Robotic fish tracking method based on suboptimal interval Kalman filter

NASA Astrophysics Data System (ADS)

Tong, Xiaohong; Tang, Chao

2017-11-01

Autonomous Underwater Vehicle (AUV) research focused on tracking and positioning, precise guidance and return to dock and other fields. The robotic fish of AUV has become a hot application in intelligent education, civil and military etc. In nonlinear tracking analysis of robotic fish, which was found that the interval Kalman filter algorithm contains all possible filter results, but the range is wide, relatively conservative, and the interval data vector is uncertain before implementation. This paper proposes a ptimization algorithm of suboptimal interval Kalman filter. Suboptimal interval Kalman filter scheme used the interval inverse matrix with its worst inverse instead, is more approximate nonlinear state equation and measurement equation than the standard interval Kalman filter, increases the accuracy of the nominal dynamic system model, improves the speed and precision of tracking system. Monte-Carlo simulation results show that the optimal trajectory of sub optimal interval Kalman filter algorithm is better than that of the interval Kalman filter method and the standard method of the filter.

Influence of Inter-Training Intervals on Intermanual Transfer Effects in Upper-Limb Prosthesis Training: A Randomized Pre-Posttest Study.

PubMed

Romkema, Sietske; Bongers, Raoul M; van der Sluis, Corry K

2015-01-01

Improvement in prosthetic training using intermanual transfer (the transfer of motor skills from the trained, “unaffected” hand to the untrained, “affected” hand) has been shown in previous studies. The aim of this study is to determine the influence of the inter-training interval on the magnitude of the intermanual transfer effects. This was done using a mechanistic, randomized, single-blinded pretest-posttest design. Sixty-four able-bodied, right-handed participants were randomly assigned to the Short and Long Interval Training Groups and the Short and Long Interval Control Groups. The Short and Long Interval Training Groups used a prosthesis simulator in their training program. The Short and Long Interval Control Groups executed a sham training program, that is, a dummy training program in which the same muscles were trained as with the prosthesis simulator. The Short Interval Training Group and the Short Interval Control Groups trained on consecutive days, while the Long Interval Training Group and Long Interval Control Group trained twice a week. To determine the improvement in skills, a test was administered before, immediately after, and at two points in time after the training. Training was performed with the “unaffected” arm; tests were performed with the “affected” arm. The outcome measurements were: the movement time (the time from the beginning of the movement until completion of the task); the duration of maximum hand opening, (the opening of the prosthetic hand while grasping an object); and the grip-force control (the error from the required grip-force during a tracking task). Intermanual transfer was found in movement times, but not in hand opening or grip-force control. The length of the inter-training interval did not affect the magnitude of intermanual transfer effects. No difference in the intermanual transfer effect in upper-limb prosthesis training was found for training on a daily basis as compared to training twice a week. Nederlands Trial Register NTR3888.

Influence of Inter-Training Intervals on Intermanual Transfer Effects in Upper-Limb Prosthesis Training: A Randomized Pre-Posttest Study

PubMed Central

Romkema, Sietske; Bongers, Raoul M.; van der Sluis, Corry K.

2015-01-01

Improvement in prosthetic training using intermanual transfer (the transfer of motor skills from the trained, “unaffected” hand to the untrained, “affected” hand) has been shown in previous studies. The aim of this study is to determine the influence of the inter-training interval on the magnitude of the intermanual transfer effects. This was done using a mechanistic, randomized, single-blinded pretest-posttest design. Sixty-four able-bodied, right-handed participants were randomly assigned to the Short and Long Interval Training Groups and the Short and Long Interval Control Groups. The Short and Long Interval Training Groups used a prosthesis simulator in their training program. The Short and Long Interval Control Groups executed a sham training program, that is, a dummy training program in which the same muscles were trained as with the prosthesis simulator. The Short Interval Training Group and the Short Interval Control Groups trained on consecutive days, while the Long Interval Training Group and Long Interval Control Group trained twice a week. To determine the improvement in skills, a test was administered before, immediately after, and at two points in time after the training. Training was performed with the “unaffected” arm; tests were performed with the “affected” arm. The outcome measurements were: the movement time (the time from the beginning of the movement until completion of the task); the duration of maximum hand opening, (the opening of the prosthetic hand while grasping an object); and the grip-force control (the error from the required grip-force during a tracking task). Intermanual transfer was found in movement times, but not in hand opening or grip-force control. The length of the inter-training interval did not affect the magnitude of intermanual transfer effects. No difference in the intermanual transfer effect in upper-limb prosthesis training was found for training on a daily basis as compared to training twice a week. Trial Registration Nederlands Trial Register NTR3888 PMID:26075396

Lactic acid bacteria in the quality improvement and depreciation of wine.

PubMed

Lonvaud-Funel, A

1999-01-01

The winemaking process includes two main steps: lactic acid bacteria are responsible for the malolactic fermentation which follows the alcoholic fermentation by yeasts. Both types of microorganisms are present on grapes and on cellar equipment. Yeasts are better adapted to growth in grape must than lactic acid bacteria, so the alcoholic fermentation starts quickly. In must, up to ten lactic acid bacteria species can be identified. They belong to the Lactobacillus, Pediococcus, Leuconostoc and Oenococcus genera. Throughout alcoholic fermentation, a natural selection occurs and finally the dominant species is O. oeni, due to interactions between yeasts and bacteria and between bacteria themselves. After bacterial growth, when the population is over 10(6) CFU/ml, malolactic transformation is the obvious change in wine composition. However, many other substrates can be metabolized. Some like remaining sugars and citric acid are always assimilated by lactic acid bacteria, thus providing them with energy and carbon. Other substrates such as some amino acids may be used following pathways restricted to strains carrying the adequate enzymes. Some strains can also produce exopolysaccharides. All these transformations greatly influence the sensory and hygienic quality of wine. Malic acid transformation is encouraged because it induces deacidification. Diacetyl produced from citric acid is also helpful to some extent. Sensory analyses show that many other reactions change the aromas and make malolactic fermentation beneficial, but they are as yet unknown. On the contrary, an excess of acetic acid, the synthesis of glucane, biogenic amines and precursors of ethylcarbamate are undesirable. Fortunately, lactic acid bacteria normally multiply in dry wines; moreover some of these activities are not widespread. Moreover, the most striking trait of wine lactic acid bacteria is their capacity to adapt to a hostile environment. The mechanisms for this are not yet completely elucidated. Molecular biology has provided some explanations for the behaviour and the metabolism of bacteria in wine. New tools are now available to detect the presence of desirable and undesirable strains. Even if much remains unknown, winemakers and oenologists can nowadays better control the process. By acting upon the diverse microflora and grape musts, they are more able to produce healthy and pleasant wines.

[Significance of bacteria detection with filter paper method on diagnosis of diabetic foot wound infection].

PubMed

Zou, X H; Zhu, Y P; Ren, G Q; Li, G C; Zhang, J; Zou, L J; Feng, Z B; Li, B H

2017-02-20

Objective: To evaluate the significance of bacteria detection with filter paper method on diagnosis of diabetic foot wound infection. Methods: Eighteen patients with diabetic foot ulcer conforming to the study criteria were hospitalized in Liyuan Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from July 2014 to July 2015. Diabetic foot ulcer wounds were classified according to the University of Texas diabetic foot classification (hereinafter referred to as Texas grade) system, and general condition of patients with wounds in different Texas grade was compared. Exudate and tissue of wounds were obtained, and filter paper method and biopsy method were adopted to detect the bacteria of wounds of patients respectively. Filter paper method was regarded as the evaluation method, and biopsy method was regarded as the control method. The relevance, difference, and consistency of the detection results of two methods were tested. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of filter paper method in bacteria detection were calculated. Receiver operating characteristic (ROC) curve was drawn based on the specificity and sensitivity of filter paper method in bacteria detection of 18 patients to predict the detection effect of the method. Data were processed with one-way analysis of variance and Fisher's exact test. In patients tested positive for bacteria by biopsy method, the correlation between bacteria number detected by biopsy method and that by filter paper method was analyzed with Pearson correlation analysis. Results: (1) There were no statistically significant differences among patients with wounds in Texas grade 1, 2, and 3 in age, duration of diabetes, duration of wound, wound area, ankle brachial index, glycosylated hemoglobin, fasting blood sugar, blood platelet count, erythrocyte sedimentation rate, C-reactive protein, aspartate aminotransferase, serum creatinine, and urea nitrogen (with F values from 0.029 to 2.916, P values above 0.05), while there were statistically significant differences among patients with wounds in Texas grade 1, 2, and 3 in white blood cell count and alanine aminotransferase (with F values 4.688 and 6.833 respectively, P <0.05 or P <0.01). (2) According to the results of biopsy method, 6 patients were tested negative for bacteria, and 12 patients were tested positive for bacteria, among which 10 patients were with bacterial number above 1×10(5)/g, and 2 patients with bacterial number below 1×10(5)/g. According to the results of filter paper method, 8 patients were tested negative for bacteria, and 10 patients were tested positive for bacteria, among which 7 patients were with bacterial number above 1×10(5)/g, and 3 patients with bacterial number below 1×10(5)/g. There were 7 patients tested positive for bacteria both by biopsy method and filter paper method, 8 patients tested negative for bacteria both by biopsy method and filter paper method, and 3 patients tested positive for bacteria by biopsy method but negative by filter paper method. Patients tested negative for bacteria by biopsy method did not tested positive for bacteria by filter paper method. There was directional association between the detection results of two methods ( P =0.004), i. e. if result of biopsy method was positive, result of filter paper method could also be positive. There was no obvious difference in the detection results of two methods ( P =0.250). The consistency between the detection results of two methods was ordinary (Kappa=0.68, P =0.002). (3) The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of filter paper method in bacteria detection were 70%, 100%, 1.00, 0.73, and 83.3%, respectively. Total area under ROC curve of bacteria detection by filter paper method in 18 patients was 0.919 (with 95% confidence interval 0-1.000, P =0.030). (4) There were 13 strains of bacteria detected by biopsy method, with 5 strains of Acinetobacter baumannii, 5 strains of Staphylococcus aureus, 1 strain of Pseudomonas aeruginosa, 1 strain of Streptococcus bovis, and 1 strain of bird Enterococcus . There were 11 strains of bacteria detected by filter paper method, with 5 strains of Acinetobacter baumannii, 3 strains of Staphylococcus aureus, 1 strain of Pseudomonas aeruginosa, 1 strain of Streptococcus bovis, and 1 strain of bird Enterococcus . Except for Staphylococcus aureus, the sensitivity and specificity of filter paper method in the detection of the other 4 bacteria were all 100%. The consistency between filter paper method and biopsy method in detecting Acinetobacter baumannii was good (Kappa=1.00, P <0.01), while that in detecting Staphylococcus aureus was ordinary (Kappa=0.68, P <0.05). (5) There was no obvious correlation between the bacteria number of wounds detected by filter paper method and that by biopsy method ( r =0.257, P =0.419). There was obvious correlation between the bacteria numbers detected by two methods in wounds with Texas grade 1 and 2 (with r values as 0.999, P values as 0.001). There was no obvious correlation between the bacteria numbers detected by two methods in wounds with Texas grade 3 ( r =-0.053, P =0.947). Conclusions: The detection result of filter paper method is in accordance with that of biopsy method in the determination of bacterial infection, and it is of great importance in the diagnosis of local infection of diabetic foot wound.

Effect of PR Interval on Outcomes Following Cardiac Resynchronization Therapy: A Secondary Analysis of the COMPANION Trial.

PubMed

Lin, Jeffrey; Buhr, Kevin A; Kipp, Ryan

2017-02-01

Prolonged PR intervals may impair atrioventricular mechanical coupling and adversely affect cardiac performance. We hypothesize that patients with advanced systolic heart failure, wide QRS complexes, and prolonged PR intervals will have improved survival from CRT-D regardless of whether left bundle branch block (LBBB) or non-LBBB is present. A total of 308 patients enrolled in the optimal pharmacologic therapy (OPT) and 595 patients in the cardiac resynchronization therapy with defibrillation (CRT-D) arms of the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure trial were stratified according to normal (≤230 ms) or prolonged PR interval (>230 ms). The incidence of all-cause mortality (ACM) or hospitalization (primary endpoint) and ACM (secondary endpoint) was compared using Kaplan-Meier curves. Cox proportional hazards models for the primary and secondary endpoints were fit with LBBB status and baseline PR interval. CRT-D treatment reduced both hospitalization/ACM (P = 0.002) and ACM (P = 0.003) compared to OPT. However, CRT-D was increasingly more effective in reducing ACM hazard in patients with longer baseline PR intervals (P = 0.002) regardless of LBBB status. In particular, in the prolonged baseline PR interval subgroup, ACM was reduced with CRT-D compared to OPT (P = 0.001) with little evidence of ACM reduction in the normal PR subgroup (P = 0.07). In patients with advanced systolic heart failure, wide QRS complexes, and prolonged PR intervals, restoration of atrioventricular mechanical coupling with CRT-D may improve survival regardless of LBBB status. In patients with non-LBBB, a benefit from CRT-D may occur with prolonged PR intervals. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

A pilot study examining the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular risk factors in cancer survivors.

PubMed

Toohey, Kellie; Pumpa, Kate L; Arnolda, Leonard; Cooke, Julie; Yip, Desmond; Craft, Paul S; Semple, Stuart

2016-01-01

The aim of this study was to evaluate the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular disease risk factors in cancer survivors. Cancer survivors within 24 months post-diagnosis were randomly assigned into the low-volume high-intensity interval training group ( n  = 8) or the continuous low to moderate intensity training group ( n  = 8) group for 36 sessions (12 weeks) of supervised exercise. The low-volume high-intensity interval training (LVHIIT) group performed 7 × 30 s intervals (≥85% maximal heart rate) and the continuous low to moderate intensity training (CLMIT) group performed continuous aerobic training for 20 min (≤55% maximal heart rate) on a stationary bike or treadmill. Significant improvements (time) were observed for 13 of the 23 dependent variables (ES 0.05-0.61, p  ≤ 0.05). An interaction effect was observed for six minute walk test (18.53% [32.43-4.63] ES 0.50, p  ≤ 0.01) with the LVHIIT group demonstrating greater improvements. These preliminary findings suggest that both interventions can induce improvements in quality of life, functional capacity and selected cardiovascular disease risk factors. The LVHIIT program was well tolerated by the participants and our results suggest that LVHIIT is the preferred modality to improve fitness (6MWT); it remains to be seen which intervention elicits the most clinically relevant outcomes for patients. A larger sample size with a control group is required to confirm the significance of these findings.

A pilot study examining the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular risk factors in cancer survivors

PubMed Central

Pumpa, Kate L.; Arnolda, Leonard; Cooke, Julie; Yip, Desmond; Craft, Paul S.; Semple, Stuart

2016-01-01

Purpose The aim of this study was to evaluate the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular disease risk factors in cancer survivors. Methods Cancer survivors within 24 months post-diagnosis were randomly assigned into the low-volume high-intensity interval training group (n = 8) or the continuous low to moderate intensity training group (n = 8) group for 36 sessions (12 weeks) of supervised exercise. The low-volume high-intensity interval training (LVHIIT) group performed 7 × 30 s intervals (≥85% maximal heart rate) and the continuous low to moderate intensity training (CLMIT) group performed continuous aerobic training for 20 min (≤55% maximal heart rate) on a stationary bike or treadmill. Results Significant improvements (time) were observed for 13 of the 23 dependent variables (ES 0.05–0.61, p ≤ 0.05). An interaction effect was observed for six minute walk test (18.53% [32.43–4.63] ES 0.50, p ≤ 0.01) with the LVHIIT group demonstrating greater improvements. Conclusion These preliminary findings suggest that both interventions can induce improvements in quality of life, functional capacity and selected cardiovascular disease risk factors. The LVHIIT program was well tolerated by the participants and our results suggest that LVHIIT is the preferred modality to improve fitness (6MWT); it remains to be seen which intervention elicits the most clinically relevant outcomes for patients. A larger sample size with a control group is required to confirm the significance of these findings. PMID:27781180

Inactivation of the Haemophilus ducreyi luxS gene affects the virulence of this pathogen in human subjects.

PubMed

Labandeira-Rey, Maria; Janowicz, Diane M; Blick, Robert J; Fortney, Kate R; Zwickl, Beth; Katz, Barry P; Spinola, Stanley M; Hansen, Eric J

2009-08-01

Haemophilus ducreyi 35000HP contains a homologue of the luxS gene, which encodes an enzyme that synthesizes autoinducer 2 (AI-2) in other gram-negative bacteria. H. ducreyi 35000HP produced AI-2 that functioned in a Vibrio harveyi-based reporter system. A H. ducreyi luxS mutant was constructed by insertional inactivation of the luxS gene and lost the ability to produce AI-2. Provision of the H. ducreyi luxS gene in trans partially restored AI-2 production by the mutant. The luxS mutant was compared with its parent for virulence in the human challenge model of experimental chancroid. The pustule-formation rate in 5 volunteers was 93.3% (95% confidence interval, 81.7%-99.9%) at 15 parent sites and 60.0% (95% confidence interval, 48.3%-71.7%) at 15 mutant sites (1-tailed P < .001). Thus, the luxS mutant was partially attenuated for virulence. This is the first report of AI-2 production contributing to the pathogenesis of a genital ulcer disease.

Long-term lifestyle intervention with optimized high-intensity interval training improves body composition, cardiometabolic risk, and exercise parameters in patients with abdominal obesity.

PubMed

Gremeaux, Vincent; Drigny, Joffrey; Nigam, Anil; Juneau, Martin; Guilbeault, Valérie; Latour, Elise; Gayda, Mathieu

2012-11-01

The aim of this study was to study the impact of a combined long-term lifestyle and high-intensity interval training intervention on body composition, cardiometabolic risk, and exercise tolerance in overweight and obese subjects. Sixty-two overweight and obese subjects (53.3 ± 9.7 yrs; mean body mass index, 35.8 ± 5 kg/m(2)) were retrospectively identified at their entry into a 9-mo program consisting of individualized nutritional counselling, optimized high-intensity interval exercise, and resistance training two to three times a week. Anthropometric measurements, cardiometabolic risk factors, and exercise tolerance were measured at baseline and program completion. Adherence rate was 97%, and no adverse events occurred with high-intensity interval exercise training. Exercise training was associated with a weekly energy expenditure of 1582 ± 284 kcal. Clinically and statistically significant improvements were observed for body mass (-5.3 ± 5.2 kg), body mass index (-1.9 ± 1.9 kg/m(2)), waist circumference (-5.8 ± 5.4 cm), and maximal exercise capacity (+1.26 ± 0.84 metabolic equivalents) (P < 0.0001 for all parameters). Total fat mass and trunk fat mass, lipid profile, and triglyceride/high-density lipoprotein ratio were also significantly improved (P < 0.0001). At program completion, the prevalence of metabolic syndrome was reduced by 32.5% (P < 0.05). Independent predictors of being a responder to body mass and waist circumference loss were baseline body mass index and resting metabolic rate; those for body mass index decrease were baseline waist circumference and triglyceride/high-density lipoprotein cholesterol ratio. A long-term lifestyle intervention with optimized high-intensity interval exercise improves body composition, cardiometabolic risk, and exercise tolerance in obese subjects. This intervention seems safe, efficient, and well tolerated and could improve adherence to exercise training in this population.

Killing of Staphylococcus aureus via Magnetic Hyperthermia Mediated by Magnetotactic Bacteria

PubMed Central

Chen, Changyou; Chen, Linjie; Yi, Yong; Chen, Chuanfang

2016-01-01

Staphylococcus aureus is a common hospital and household pathogen. Given the emergence of antibiotic-resistant derivatives of this pathogen resulting from the use of antibiotics as general treatment, development of alternative therapeutic strategies is urgently needed. Here, we assess the feasibility of killing S. aureus cells in vitro and in vivo through magnetic hyperthermia mediated by magnetotactic bacteria that possess magnetic nanocrystals and demonstrate magnetically steered swimming. The S. aureus suspension was added to magnetotactic MO-1 bacteria either directly or after coating with anti-MO-1 polyclonal antibodies. The suspensions were then subjected to an alternating magnetic field (AMF) for 1 h. S. aureus viability was subsequently assessed through conventional plate counting and flow cytometry. We found that approximately 30% of the S. aureus cells mixed with uncoated MO-1 cells were killed after AMF treatment. Moreover, attachment between the magnetotactic bacteria and S. aureus increased the killing efficiency of hyperthermia to more than 50%. Using mouse models, we demonstrated that magnetic hyperthermia mediated by antibody-coated magnetotactic MO-1 bacteria significantly improved wound healing. These results collectively demonstrated the effective eradication of S. aureus both in vitro and in vivo, indicating the potential of magnetotactic bacterium-mediated magnetic hyperthermia as a treatment for S. aureus-induced skin or wound infections. PMID:26873320

Nitrogen source effects on the denitrifying anaerobic methane oxidation culture and anaerobic ammonium oxidation bacteria enrichment process.

PubMed

Fu, Liang; Ding, Jing; Lu, Yong-Ze; Ding, Zhao-Wei; Zeng, Raymond J

2017-05-01

The co-culture system of denitrifying anaerobic methane oxidation (DAMO) and anaerobic ammonium oxidation (Anammox) has a potential application in wastewater treatment plant. This study explored the effects of permutation and combination of nitrate, nitrite, and ammonium on the culture enrichment from freshwater sediments. The co-existence of NO 3 - , NO 2 - , and NH 4 + shortened the enrichment time from 75 to 30 days and achieved a total nitrogen removal rate of 106.5 mg/L/day on day 132. Even though ammonium addition led to Anammox bacteria increase and a higher nitrogen removal rate, DAMO bacteria still dominated in different reactors with the highest proportion of 64.7% and the maximum abundance was 3.07 ± 0.25 × 10 8 copies/L (increased by five orders of magnitude) in the nitrite reactor. DAMO bacteria showed greater diversity in the nitrate reactor, and one was similar to M. oxyfera; DAMO bacteria in the nitrite reactor were relatively unified and similar to M. sinica. Interestingly, no DAMO archaea were found in the nitrate reactor. This study will improve the understanding of the impact of nitrogen source on DAMO and Anammox co-culture enrichment.

The Effects of Vaccination and Immunity on Bacterial Infection Dynamics In Vivo

PubMed Central

Coward, Chris; Restif, Olivier; Dybowski, Richard; Grant, Andrew J.; Maskell, Duncan J.; Mastroeni, Pietro

2014-01-01

Salmonella enterica infections are a significant global health issue, and development of vaccines against these bacteria requires an improved understanding of how vaccination affects the growth and spread of the bacteria within the host. We have combined in vivo tracking of molecularly tagged bacterial subpopulations with mathematical modelling to gain a novel insight into how different classes of vaccines and branches of the immune response protect against secondary Salmonella enterica infections of the mouse. We have found that a live Salmonella vaccine significantly reduced bacteraemia during a secondary challenge and restrained inter-organ spread of the bacteria in the systemic organs. Further, fitting mechanistic models to the data indicated that live vaccine immunisation enhanced both the bacterial killing in the very early stages of the infection and bacteriostatic control over the first day post-challenge. T-cell immunity induced by this vaccine is not necessary for the enhanced bacteriostasis but is required for subsequent bactericidal clearance of Salmonella in the blood and tissues. Conversely, a non-living vaccine while able to enhance initial blood clearance and killing of virulent secondary challenge bacteria, was unable to alter the subsequent bacterial growth rate in the systemic organs, did not prevent the resurgence of extensive bacteraemia and failed to control the spread of the bacteria in the body. PMID:25233077

Developing of a novel antibacterial agent by functionalization of graphene oxide with guanidine polymer with enhanced antibacterial activity

NASA Astrophysics Data System (ADS)

Li, Ping; Sun, Shiyu; Dong, Alideertu; Hao, Yanping; Shi, Shuangqiang; Sun, Zijia; Gao, Ge; Chen, Yuxin

2015-11-01

New materials with excellent antibacterial activity attract numerous research interests. Herein, a facile synthetic method of polyethylene glycol (PEG) and polyhexamethylene guanidine hydrochloride (PHGC) dual-polymer-functionalized graphene oxide (GO) (GO-PEG-PHGC), a novel antibacterial material, was reported. The as-prepared products were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), X-ray pattern (XRD) and elemental analysis. The antibacterial effect on the bacterial strain was investigated by incubating both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). The results show that GO-PEG-PHGC has enhanced antibacterial activity when compared to GO, GO-PEG or GO-PHGC alone. The improved antibacterial activity was described to be related to a better dispersion of GO-PEG-PHGC in the presence of PEG. This better dispersion leads to a greater contact between the bacteria membrane and nanomaterials, therefore leading to greater cell damage. Not only Gram-negative bacteria but also Gram-positive bacteria are greatly inhibited by this antibacterial agent. With the powerful antibacterial activity as well as its low cost and facile preparation, the GO-PEG-PHGC as a novel antibacterial agent can find potential application in the areas of healthcare and environmental engineering.

Short communication: Intestinal digestibility of amino acids in fluid- and particle-associated rumen bacteria determined using a precision-fed cecectomized rooster bioassay.

PubMed

Fonseca, A C; Fredin, S M; Ferraretto, L F; Parsons, C M; Utterback, P L; Shaver, R D

2014-01-01

Microbial protein represents the majority of metabolizable protein absorbed by ruminant animals. Enhanced understanding of the AA digestibility of rumen microbes will improve estimates of metabolizable protein. The objective of this experiment was to determine the digestibility of AA in fluid- (FAB) and particle-associated bacteria (PAB) using the precision-fed cecectomized rooster bioassay. Bacteria were isolated from 4 ruminally cannulated lactating Holstein cows by differential centrifugation, including particle suspension in 0.1% Tween-80 for increased removal of PAB from ruminal digesta. Samples of FAB and PAB were fed to 9 cecectomized roosters to determine standardized digestibility of AA. Total AA digestibility was 76.8 and 75.5% for FAB and PAB, respectively, but did not differ. Differences existed in AA digestibilities within bacterial type when compared with the mean essential AA digestibility value. Compared with previous literature estimates of AA digestibility in microbes (mean = 76%; range = 57-87%) and relative to National Research Council estimates of total AA from rumen bacteria (80%), the precision-fed cecectomized rooster assay is an acceptable in vivo model to determine AA digestibility of rumen bacteria. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Genetic analysis of stress responses in soil bacteria for enhanced bioremediation of mixed contaminants. 1997 annual progress report

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

Wong, K.K.

'To provide increased knowledge of stress responses of indigenous microbes at contaminated sites as well as using microbes as molecular probes for monitoring the performance and effectiveness of bioremediation, the authors propose to identify the stress-inducible genes and promoters from two soil bacteria, Deinococcus radiodurans and Sphingomonas F199. These organisms represent two phylogenetically distinct groups of soil bacteria, each of which has specific features of interest for bioremediation. D. radiodurans exhibits high resistance to external stress; F199 is a deep subsurface (Savannah River Site) organism with unique degradative capabilities. Research Statement To realize the full potential of bioremediation, an understandingmore » of microbial community and individual bacterial responses to the stresses encountered at contaminated sites is needed. Knowledge about genetic responses of soil and subsurface bacteria to environmental stresses, which include low nutrients, low oxygen, and mixed pollutants, will allow extrapolation of basic principles to field applications either using indigenous bacteria or genetically engineered microorganisms. Defining bacterial responses to those stresses presents an opportunity for improving bioremediation strategies, and should contribute to environmental management and restoration actions that would reduce the cost and time required to achieve DOE''s cleanup goals.'« less

Understanding How Commensal Obligate Anaerobic Bacteria Regulate Immune Functions in the Large Intestine

PubMed Central

Maier, Eva; Anderson, Rachel C.; Roy, Nicole C.

2014-01-01

The human gastrointestinal tract is colonised by trillions of commensal bacteria, most of which are obligate anaerobes residing in the large intestine. Appropriate bacterial colonisation is generally known to be critical for human health. In particular, the development and function of the immune system depends on microbial colonisation, and a regulated cross-talk between commensal bacteria, intestinal epithelial cells and immune cells is required to maintain mucosal immune homeostasis. This homeostasis is disturbed in various inflammatory disorders, such as inflammatory bowel diseases. Several in vitro and in vivo studies indicate a role for Faecalibacterium prausnitzii, Bacteroides thetaiotaomicron, Bacteroides fragilis, Akkermansia muciniphila and segmented filamentous bacteria in maintaining intestinal immune homeostasis. These obligate anaerobes are abundant in the healthy intestine but reduced in several inflammatory diseases, suggesting an association with protective effects on human health. However, knowledge of the mechanisms underlying the effects of obligate anaerobic intestinal bacteria remains limited, in part due to the difficulty of co-culturing obligate anaerobes together with oxygen-requiring human epithelial cells. By using novel dual-environment co-culture models, it will be possible to investigate the effects of the unstudied majority of intestinal microorganisms on the human epithelia. This knowledge will provide opportunities for improving human health and reducing the risk of inflammatory diseases. PMID:25545102

Potentiating the Activity of Nisin against Escherichia coli

PubMed Central

Zhou, Liang; van Heel, Auke J.; Montalban-Lopez, Manuel; Kuipers, Oscar P.

2016-01-01

Lantibiotics are antimicrobial (methyl)lanthionine-containing peptides produced by various Gram-positive bacteria. The model lantibiotic, nisin, binds lipid II in the cell membrane. Additionally, after binding it can insert into the membrane creating a pore. Nisin can efficiently inhibit the growth of Gram-positive bacteria and resistance is rarely observed. However, the activity of lantibiotics is at least 100-fold lower against certain Gram-negative bacteria. This is caused by the fact that Gram-negative bacteria have an outer membrane that hinders the peptides to reach lipid II, which is located in the inner membrane. Improving the activity of lantibiotics against Gram-negative bacteria could be achieved if the outer membrane traversing efficiency is increased. Here, several anti-Gram-negative peptides (e.g., apidaecin 1b, oncocin), or parts thereof, were fused to the C-terminus of either a truncated version of nisin containing the first three/five rings or full length nisin. The activities of these fusion peptides were tested against Gram-negative pathogens. Our results showed that when an eight amino acids (PRPPHPRL) tail from apidaecin 1b was attached to nisin, the activity of nisin against Escherichia coli CECT101 was increased more than two times. This research presents a new and promising method to increase the anti-Gram-negative activity of lantibiotics. PMID:26904542

Understanding how commensal obligate anaerobic bacteria regulate immune functions in the large intestine.

PubMed

Maier, Eva; Anderson, Rachel C; Roy, Nicole C

2014-12-24

The human gastrointestinal tract is colonised by trillions of commensal bacteria, most of which are obligate anaerobes residing in the large intestine. Appropriate bacterial colonisation is generally known to be critical for human health. In particular, the development and function of the immune system depends on microbial colonisation, and a regulated cross-talk between commensal bacteria, intestinal epithelial cells and immune cells is required to maintain mucosal immune homeostasis. This homeostasis is disturbed in various inflammatory disorders, such as inflammatory bowel diseases. Several in vitro and in vivo studies indicate a role for Faecalibacterium prausnitzii, Bacteroides thetaiotaomicron, Bacteroides fragilis, Akkermansia muciniphila and segmented filamentous bacteria in maintaining intestinal immune homeostasis. These obligate anaerobes are abundant in the healthy intestine but reduced in several inflammatory diseases, suggesting an association with protective effects on human health. However, knowledge of the mechanisms underlying the effects of obligate anaerobic intestinal bacteria remains limited, in part due to the difficulty of co-culturing obligate anaerobes together with oxygen-requiring human epithelial cells. By using novel dual-environment co-culture models, it will be possible to investigate the effects of the unstudied majority of intestinal microorganisms on the human epithelia. This knowledge will provide opportunities for improving human health and reducing the risk of inflammatory diseases.

Incidence of Staphylococcus aureus and analysis of associated bacterial communities on food industry surfaces.

PubMed

Gutiérrez, Diana; Delgado, Susana; Vázquez-Sánchez, Daniel; Martínez, Beatriz; Cabo, Marta López; Rodríguez, Ana; Herrera, Juan J; García, Pilar

2012-12-01

Biofilms are a common cause of food contamination with undesirable bacteria, such as pathogenic bacteria. Staphylococcus aureus is one of the major bacteria causing food-borne diseases in humans. A study designed to determine the presence of S. aureus on food contact surfaces in dairy, meat, and seafood environments and to identify coexisting microbiota has therefore been carried out. A total of 442 samples were collected, and the presence of S. aureus was confirmed in 6.1% of samples. Sixty-three S. aureus isolates were recovered and typed by random amplification of polymorphic DNA (RAPD). Profiles were clustered into four groups which were related to specific food environments. All isolates harbored some potential virulence factors such as enterotoxin production genes, biofilm formation-associated genes, antibiotic resistance, or lysogeny. PCR-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprints of bacterial communities coexisting with S. aureus revealed the presence of bacteria either involved in food spoilage or of concern for food safety in all food environments. Food industry surfaces could thus be a reservoir for S. aureus forming complex communities with undesirable bacteria in multispecies biofilms. Uneven microbiological conditions were found in each food sector, which indicates the need to improve hygienic conditions in food processing facilities, particularly the removal of bacterial biofilms, to enhance the safety of food products.

Role of granular activated carbon in the microalgal cultivation from bacteria contamination.

PubMed

Ni, Zhi-Yi; Li, Jing-Ya; Xiong, Zhao-Zhao; Cheng, Li-Hua; Xu, Xin-Hua

2018-01-01

Microalgal wastewater treatment has been considered as one of the most promising measures to treat nitrogen and phosphorus in the municipal wastewater. While the municipal wastewater provides sufficient nitrogen and phosphorus for microalgal growth, the microalgae still faces serious biological contamination caused by bacteria in wastewater. In this study, the commercial granular activated carbon (GAC) was added into the simulated municipal wastewater to avoid the influence of bacteria on the growth of microalgae. The extracellular organic matter (EOM) in microalgal broth was then characterized to enlighten the role of GAC in reducing the bioavailability of EOM. The results showed that the GAC addition could increase the dry weight of microalgae from 0.06mgL -1 to 0.46mgL -1 under the condition of bacterial inoculation. The GAC could mitigate bacterial contamination mainly due to its adsorption of both bacteria and EOM that might contain algicidal extracellular substances. Moreover, compared to the control group, the GAC addition could mitigate the microalgal lysis caused by bacteria and thus greatly reduce the bioavailability of EOM from 2.80mgL -1 to 0.61mgL -1 , which was beneficial for the improvement of biostability and reuse of effluent after the microalgal harvesting. Copyright © 2017 Elsevier Ltd. All rights reserved.

An improved method for generating axenic entomopathogenic nematodes.

PubMed

Yadav, Shruti; Shokal, Upasana; Forst, Steven; Eleftherianos, Ioannis

2015-09-19

Steinernema carpocapsae are parasitic nematodes that invade and kill insects. The nematodes are mutualistically associated with the bacteria Xenorhabdus nematophila and together form an excellent model to study pathogen infection processes and host anti-nematode/antibacterial immune responses. To determine the contribution of S. carpocapsae and their associated X. nematophila to the successful infection of insects as well as to investigate the interaction of each mutualistic partner with the insect immune system, it is important to develop and establish robust methods for generating nematodes devoid of their bacteria. To produce S. carpocapsae nematodes without their associated X. nematophila bacteria, we have modified a previous method, which involves the use of a X. nematophila rpoS mutant strain that fails to colonize the intestine of the worms. We confirmed the absence of bacteria in the nematodes using a molecular diagnostic and two rounds of an axenicity assay involving appropriate antibiotics and nematode surface sterilization. We used axenic and symbiotic S. carpocapsae to infect Drosophila melanogaster larvae and found that both types of nematodes were able to cause insect death at similar rates. Generation of entomopathogenic nematodes lacking their mutualistic bacteria provides an excellent tool to dissect the molecular and genetic basis of nematode parasitism and to identify the insect host immune factors that participate in the immune response against nematode infections.

Gluten-degrading bacteria are present in the human small intestine of healthy volunteers and celiac patients.

PubMed

Herrán, Alexandra R; Pérez-Andrés, Jénifer; Caminero, Alberto; Nistal, Esther; Vivas, Santiago; Ruiz de Morales, José María; Casqueiro, Javier

2017-09-01

Gluten is the only known environmental factor that triggers celiac disease. Several studies have described an imbalance between the intestinal microbiota of different individuals based on diagnoses. Moreover, recent studies have suggested that human bacteria may play an important role in gluten hydrolysis. However, there has been no research focusing on the small intestine. This study aimed to characterize the adult small intestine microbiota possibly implicated in gluten hydrolysis. Duodenal biopsies from different diagnosed individuals were cultured in a gluten-containing medium, and the grown microbiota was analyzed by culture dependent/independent methods. Results showed that gluten-degrading bacteria can be found in the human small intestine. Indeed, 114 bacterial strains belonging to 32 species were isolated; 85 strains were able to grow in a medium containing gluten as the sole nitrogen source, 31 strains showed extracellular proteolytic activity against gluten protein and 27 strains showed peptidolytic activity towards the 33 mer peptide, an immunogenic peptide for celiac disease patients. We found that there are no differences based on the diagnosis, but each individual has its own population of gluten-hydrolyzing bacteria. These bacteria or their gluten-degrading enzymes could help to improve the quality of life of celiac disease patients'. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

N-Acyl Homoserine Lactone-Mediated Quorum Sensing with Special Reference to Use of Quorum Quenching Bacteria in Membrane Biofouling Control

PubMed Central

Paul, Diby

2014-01-01

Membrane biofouling remains a severe problem to be addressed in wastewater treatment systems affecting reactor performance and economy. The finding that many wastewater bacteria rely on N-acyl homoserine lactone-mediated quorum sensing to synchronize their activities essential for biofilm formations; the quenching bacterial quorum sensing suggests a promising approach for control of membrane biofouling. A variety of quorum quenching compounds of both synthetic and natural origin have been identified and found effective in inhibition of membrane biofouling with much less environmental impact than traditional antimicrobials. Work over the past few years has demonstrated that enzymatic quorum quenching mechanisms are widely conserved in several prokaryotic organisms and can be utilized as a potent tool for inhibition of membrane biofouling. Such naturally occurring bacterial quorum quenching mechanisms also play important roles in microbe-microbe interactions and have been used to develop sustainable nonantibiotic antifouling strategies. Advances in membrane fabrication and bacteria entrapment techniques have allowed the implication of such quorum quenching bacteria for better design of membrane bioreactor with improved antibiofouling efficacies. In view of this, the present paper is designed to review and discuss the recent developments in control of membrane biofouling with special emphasis on quorum quenching bacteria that are applied in membrane bioreactors. PMID:25147787

Irritable Bowel Syndrome in Children

MedlinePlus

... and adjust the activity of the GI tract. Probiotics Probiotics are live microorganisms, usually bacteria, that are similar ... in the GI tract. Studies have found that probiotics, specifically Bifidobacteria and certain probiotic combinations, improve symptoms ...

4Pi-confocal microscopy of live cells

NASA Astrophysics Data System (ADS)

Bahlmann, Karsten; Jakobs, Stefan; Hell, Stefan W.

2002-06-01

By coherently adding the spherical wavefronts of two opposing lenses, two-photon excitation 4Pi-confocal fluorescence microscopy has achieved three-dimensional imaging with an axial resolution 3-7 times better than confocal microscopy. So far this improvement was possible only in glycerol-mounted, fixed cells. Here we report 4Pi-confocal microscopy of watery objects and its application to the imaging of live cells. Water immersion 4Pi-confocal microscopy of membrane stained live Escherichia coli bacteria attains a 4.3 fold better axial resolution as compared to the best water immersion confocal microscope. The resolution enhancement results into a vastly improved three-dimensional representation of the bacteria. The first images of live biological samples with an all-directional resolution in the 190-280 nm range are presented here, thus establishing a new resolution benchmark in live cell microscopy.

Growth and viability of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus in traditional yoghurt enriched by honey and whey protein concentrate.

PubMed

Glušac, J; Stijepić, M; Đurđević-Milošević, D; Milanović, S; Kanurić, K; Vukić, V

2015-01-01

The ability of whey protein concentrate (WPC) (1% w/v) and/or honey (2% and 4% w⁄v) to improve lactic acid bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) growth and viability in yoghurt during a 21 day period of storage was investigated. Another focus of this study was to examine fermentation kinetics and post-acidification rates through pH and lactic acid content measurements over the 21 day period. The addition of WPC and acacia honey accelerated fermentation and improved lactic acid bacteria (LAB) growth over the 21 days, but honey proportion did not significantly affect the viability of LAB. Moreover, adding honey and WPC did not support the overproduction of lactic acid, which positively influenced yoghurt stability during the 21 day storage period.