Habib, M Rowshahul; Karim, M Rezaul
2011-10-01
To investigate experimentally the possible antitumor effect of methanol extract (ME) of Calotropis gigantea L. (C. gigantean) root bark and its petroleum ether (PEF) and chloroform (CF) soluble fractions against Ehrlich ascites carcinoma (EAC) in Swiss albino mice. The effects of ME (10 and 20 mg/kg), PEF (40 and 80 mg/kg) and CF (20 and 40 mg/kg) on the growth of EAC and life span of EAC bearing mice were studied. Hematological profile and biochemical parameters (SALP, SGPT and SGOT) were also estimated. Results of in vivo study showed a significant decrease in viable tumor cell count and a significant increase of life span in the ME and CF treated group compared to untreated one. The life span of ME and CF treated animals was significantly (P<0.05) increased by 43.90% (20 mg ME/kg) and 57.07% (40 mg CF/kg). ME and CF brought back the hematological parameter more or less normal level. ME and CF also restored the altered levels of serum alkaline phosphatase (SALP) and serum glutamate oxaloacetate transaminase (SGOT). Methanol extract (ME) of C. gigantea root bark and its chloroform soluble fraction (CF) possesses significant antitumor activity. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.
Cholet, Céline; Delsart, Cristèle; Petrel, Mélina; Gontier, Etienne; Grimi, Nabil; L'hyvernay, Annie; Ghidossi, Remy; Vorobiev, Eugène; Mietton-Peuchot, Martine; Gény, Laurence
2014-04-02
Pulsed electric field (PEF) treatment is an emerging technology that is arousing increasing interest in vinification processes for its ability to enhance polyphenol extraction performance. The aim of this study was to investigate the effects of PEF treatment on grape skin histocytological structures and on the organization of skin cell wall polysaccharides and tannins, which, until now, have been little investigated. This study relates to the effects of two PEF treatments on harvested Cabernet Sauvignon berries: PEF1 (medium strength (4 kV/cm); short duration (1 ms)) and PEF2 (low intensity (0.7 kV/cm); longer duration (200 ms)). Histocytological observations and the study of levels of polysaccharidic fractions and total amounts of tannins allowed differentiation between the two treatments. Whereas PEF1 had little effect on the polyphenol structure and pectic fraction, PEF2 profoundly modified the organization of skin cell walls. Depending on the PEF parameters, cell wall structure was differently affected, providing variable performance in terms of polyphenol extraction and wine quality.
Senni, Michele; Paulus, Walter J.; Gavazzi, Antonello; Fraser, Alan G.; Díez, Javier; Solomon, Scott D.; Smiseth, Otto A.; Guazzi, Marco; Lam, Carolyn S. P.; Maggioni, Aldo P.; Tschöpe, Carsten; Metra, Marco; Hummel, Scott L.; Edelmann, Frank; Ambrosio, Giuseppe; Stewart Coats, Andrew J.; Filippatos, Gerasimos S.; Gheorghiade, Mihai; Anker, Stefan D.; Levy, Daniel; Pfeffer, Marc A.; Stough, Wendy Gattis; Pieske, Burkert M.
2014-01-01
The management of heart failure with reduced ejection fraction (HF-REF) has improved significantly over the last two decades. In contrast, little or no progress has been made in identifying evidence-based, effective treatments for heart failure with preserved ejection fraction (HF-PEF). Despite the high prevalence, mortality, and cost of HF-PEF, large phase III international clinical trials investigating interventions to improve outcomes in HF-PEF have yielded disappointing results. Therefore, treatment of HF-PEF remains largely empiric, and almost no acknowledged standards exist. There is no single explanation for the negative results of past HF-PEF trials. Potential contributors include an incomplete understanding of HF-PEF pathophysiology, the heterogeneity of the patient population, inadequate diagnostic criteria, recruitment of patients without true heart failure or at early stages of the syndrome, poor matching of therapeutic mechanisms and primary pathophysiological processes, suboptimal study designs, or inadequate statistical power. Many novel agents are in various stages of research and development for potential use in patients with HF-PEF. To maximize the likelihood of identifying effective therapeutics for HF-PEF, lessons learned from the past decade of research should be applied to the design, conduct, and interpretation of future trials. This paper represents a synthesis of a workshop held in Bergamo, Italy, and it examines new and emerging therapies in the context of specific, targeted HF-PEF phenotypes where positive clinical benefit may be detected in clinical trials. Specific considerations related to patient and endpoint selection for future clinical trials design are also discussed. PMID:25104786
Culetu, Alina; Fernandez-Gomez, Beatriz; Ullate, Monica; del Castillo, Maria Dolores; Andlauer, Wilfried
2016-04-15
The antiglycoxidative properties of theanine (TEF) and polyphenols enriched fractions (PEF) prepared from tea dust were tested in a model system composed of bovine serum albumin (BSA) and methylglyoxal (MGO). PEF caused a decrease in available free amino groups of BSA in presence and absence of MGO, suggesting the simultaneous occurrence of glycoxidation reaction and phenols-protein interaction. The presence of PEF and TEF inhibited formation of fluorescent advanced glycation end-products (AGEs). Moreover, theanine (TB) and polyphenol-enriched bread (PB) were formulated. A significant increase in free amino groups was observed in TBs with a dose-response effect, while addition of PEF in bread produced a significant decrease (p<0.05). PEF efficiently reduced fluorescent AGE formation in breads compared with TEF. The results are in line with the simplified model systems. PEF used as food ingredient allows obtaining a tasty food possessing health promoting properties and lower content of potential harmful compounds (AGEs). Copyright © 2015 Elsevier Ltd. All rights reserved.
Shah, Ravi V; Desai, Akshay S; Givertz, Michael M
2010-03-01
Although renin-angiotensin system (RAS) inhibitors have little demonstrable effect on mortality in patients with heart failure and preserved ejection fraction (HF-PEF), some trials have suggested a benefit with regard to reduction in HF hospitalization. Here, we systematically review and evaluate prospective clinical studies of RAS inhibitors enrolling patients with HF-PEF, including the 3 major trials of RAS inhibition (Candesartan in Patients with Chronic Heart Failure and Preserved Left Ventricular Ejection Fraction [CHARM-Preserved], Irbesartan in Patients with Heart Failure and Preserved Ejection Fraction [I-PRESERVE], and Perindopril in Elderly People with Chronic Heart Failure [PEP-CHF]). We also conducted a pooled analysis of 8021 patients in the 3 major randomized trials of RAS inhibition in HF-PEF (CHARM-Preserved, I-PRESERVE, and PEP-CHF) in fixed-effect models, finding no clear benefit with regard to all-cause mortality (odds ratio [OR] 1.03, 95% confidence interval [CI], 0.92-1.15; P=.62), or HF hospitalization (OR 0.90, 95% CI 0.80-1.02; P=.09). Although RAS inhibition may be valuable in the management of comorbidities related to HF-PEF, RAS inhibition in HF-PEF is not associated with consistent reduction in HF hospitalization or mortality in this emerging cohort. Copyright (c) 2010 Elsevier Inc. All rights reserved.
Jackson, Colette E; Castagno, Davide; Maggioni, Aldo P; Køber, Lars; Squire, Iain B; Swedberg, Karl; Andersson, Bert; Richards, A Mark; Bayes-Genis, Antoni; Tribouilloy, Christophe; Dobson, Joanna; Ariti, Cono A; Poppe, Katrina K; Earle, Nikki; Whalley, Gillian; Pocock, Stuart J; Doughty, Robert N; McMurray, John J V
2015-05-07
Low pulse pressure is a marker of adverse outcome in patients with heart failure (HF) and reduced ejection fraction (HF-REF) but the prognostic value of pulse pressure in patients with HF and preserved ejection fraction (HF-PEF) is unknown. We examined the prognostic value of pulse pressure in patients with HF-PEF [ejection fraction (EF) ≥ 50%] and HF-REF. Data from 22 HF studies were examined. Preserved left ventricular ejection fraction (LVEF) was defined as LVEF ≥ 50%. All-cause mortality at 3 years was evaluated in 27 046 patients: 22 038 with HF-REF (4980 deaths) and 5008 with HF-PEF (828 deaths). Pulse pressure was analysed in quintiles in a multivariable model adjusted for the previously reported Meta-Analysis Global Group in Chronic Heart Failure prognostic variables. Heart failure and reduced ejection fraction patients in the lowest pulse pressure quintile had the highest crude and adjusted mortality risk (adjusted hazard ratio 1.68, 95% confidence interval 1.53-1.84) compared with all other pulse pressure groups. For patients with HF-PEF, higher pulse pressure was associated with the highest crude mortality, a gradient that was eliminated after adjustment for other prognostic variables. Lower pulse pressure (especially <53 mmHg) was an independent predictor of mortality in patients with HF-REF, particularly in those with an LVEF < 30% and systolic blood pressure <140 mmHg. Overall, this relationship between pulse pressure and outcome was not consistently observed among patients with HF-PEF. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.
Dias, Germana Bueno; Gomes, Valdirene Moreira; Pereira, Umberto Zottich; Ribeiro, Suzanna F Ferreira; Carvalho, André O; Rodrigues, Rosana; Machado, Olga L Tavares; Fernandes, Kátia Valevski Sales; Ferreira, André Teixeira S; Perales, Jonas; Da Cunha, Maura
2013-01-01
Capsicum species belong to the Solanaceae family and have great social, economic and agronomical significance. The present research presents data on the isolation and characterization of Capsicum chinense Jacq. peptides which were scrutinized in relation to their toxicity towards a diverse set of yeast species. The protein extract was separated with C18 reverse-phase chromatography in high performance liquid chromatography, resulting in three different peptide enriched fractions (PEFs) termed PEF1, PEF2 and PEF3. Tricine-SDS-PAGE of the PEF2 revealed peptides with molecular masses of approximately 5.0 and 8.5 kDa. These PEFs also exhibited strong antifungal activity against different yeasts. In the presence of the PEF2, Candida tropicalis exhibited morphological changes, including cellular agglomeration and formation of pseudohyphae. Determined N-terminal sequences of PEF2 and PEF3 were proven to be highly homologous to serine proteinase inhibitors, when analysed by comparative database sequence tools. For this reason were performed protease inhibitory activity assay. The PEFs displayed high inhibitory activity against trypsin and low inhibitory activity against chymotrypsin. PEF2 and PEF3 were considerably unsusceptible to a broad interval of pH and temperatures. Due to the myriad of application of Proteinase inhibitors (PIs) in fields ranging from plant protection against pathogens and pests to medicine such as in cancer and virus replication inhibition, the discovery of new PIs with new properties are of great interest.
Oskoueian, Ehsan; Abdullah, Norhani; Zulkifli, Idrus; Ebrahimi, Mahdi; Karimi, Ehsan; Goh, Yong Meng; Oskoueian, Armin; Shakeri, Majid
2015-10-30
Palm kernel cake (PKC), a by-product of the palm oil industry is abundantly available in many tropical and subtropical countries. The product is known to contain high levels of phenolic compounds that may impede the deleterious effects of fungal mycotoxins. This study focused on the evaluation of PKC phenolics as a potential cytoprotective agent towards aflatoxin B1 (AFB1)-induced cell damage. The phenolic compounds of PKC were obtained by solvent extraction and the product rich in phenolic compounds was labeled as phenolic-enriched fraction (PEF). This fraction was evaluated for its phenolic compounds composition. The antioxidant activity of PEF was determined by using 1,1-diphenyl-2-picryl-hydrazil scavenging activity, ferric reducing antioxidant power, inhibition of ß-carotene bleaching, and thiobarbituric acid reactive substances assays. The cytotoxicity assay and molecular biomarkers analyses were performed to evaluate the cytoprotective effects of PEF towards aflatoxin B1 (AFB1)-induced cell damage. The results showed that PEF contained gallic acid, pyrogallol, vanillic acid, caffeic acid, syringic acid, epicatechin, catechin and ferulic acid. The PEF exhibited free radical scavenging activity, ferric reducing antioxidant power, ß-carotene bleaching inhibition and thiobarbituric acid reactive substances inhibition. The PEF demonstrated cytoprotective effects in AFB1-treated chicken hepatocytes by reducing the cellular lipid peroxidation and enhancing antioxidant enzymes production. The viability of AFB1-treated hepatocytes was improved by PEF through up-regulation of oxidative stress tolerance genes and down-regulation of pro-inflammatory and apoptosis associated genes. The present findings supported the proposition that the phenolic compounds present in PKC could be a potential cytoprotective agent towards AFB1 cytotoxicity.
Joshi, Bhuwan Chandra; Prakash, Atish; Kalia, Ajudhia N
2015-01-01
The aim of the present study was to isolate hepatoprotective component from Urtica dioica Linn. (whole plant) against CCl 4 -induced hepatotoxicity in-vitro (HepG2 cells) and in-vivo (rats) model. Antioxidant activity of hydro alcoholic extract and its fractions petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n -butanol fraction (NBF) and aqueous fraction (AF) were determined by DPPH and NO radicals scavenging assay. Fractions were subjected to in-vitro HepG2 cell line study. Further, the most potent fraction (EAF) was subjected to in-vivo hepatoprotective potential against CCl 4 challenged rats. The in-vivo hepatoprotective active fraction was chromatographed on silica column to isolate the bioactive constituent(s). Structure elucidation was done by using various spectrophotometric techniques like UV, IR, 1 H NMR, 13 C NMR and MS spectroscopy. Ethyl acetate fraction (EAF) of hydro-alcoholic extract of U. dioica possessed the potent antioxidant activity viz. DPPH (IC 50 78.99 ± 0.17 μg/ml) and NO (IC 50 101.39 ± 0.30 μg/ml). The in-vitro HepG2 cell line study showed that the EAF prevented the cell damage. The EAF significantly attenuated the increased liver enzymes activities in serum and oxidative parameters in tissue of CCl 4 -induced rats, suggesting hepatoprotective and anti-oxidant action respectively. Column chromatography of most potent antioxidant fraction (EAF) lead to the isolation of 4-hydroxy-3-methoxy cinnamic acid (ferulic acid) which is responsible for its hepatoprotective potential. Hence, the present study suggests that EAF of hydro-alcoholic extract has significant antioxidant and hepatoprotective potential on CCl 4 induced hepatotoxicity in-vitro and in-vivo .
Watanabe, Masanari; Kurai, Jun; Sano, Hiroyuki; Shimizu, Eiji
2015-01-01
Epidemiological investigations indicate that an Asian dust storm (ADS) can aggravate respiratory disorders. However, the effects of ADS on airway inflammation remain unclear. The aim of this study was to investigate the association of exposure to ADS with airway inflammation. The subjects were 33 adult patients with asthma who measured daily peak flow expiratory (PEF) from March to May 2012. Fractional exhaled nitric oxide (FeNO) was measured before and after ADS. The FeNO values were 13.8±13.7 ppb before the ADS and 20.3±19.0 ppb after the ADS, with no significant difference. There was also no significant association of PEF with ADS exposure. However, the increase of FeNO after ADS exposure was proportional to the decrease of PEF (R=-0.78, P<0.0001). These results suggest that airway inflammation aggravated by ADS exposure may induce a decrease in pulmonary function in some adult patients with asthma.
Turner, Katy M. E.; Leung, Stella; Yu, B. Nancy; Frølund, Maria; Benfield, Thomas; Blanchard, James; Westh, Henrik; Ward, Helen
2017-01-01
Background The impact of Chlamydia trachomatis (chlamydia) control on the incidence of pelvic inflammatory disease (PID) is theoretically limited by the proportion of PID caused by chlamydia. We estimate the population excess fraction (PEF) of treated chlamydia infection on PID at 12-months in settings with widespread chlamydia control (testing and treatment) and compare this to the estimated PEF of untreated chlamydia. Methods We used two large retrospective population-based cohorts of women of reproductive age from settings with widespread chlamydia control to calculate the PEF of treated chlamydia on PID at 12-months. We undertook a systematic review to identify further studies that reported the risk of PID in women who were tested for chlamydia (infected and uninfected). We used the same method to calculate the PEF in eligible studies then compared all estimates of PEF. Results The systematic review identified a single study, a randomised controlled trial of chlamydia screening (POPI-RCT). In the presence of testing and treatment <10% of PID at 12-months was attributable to treated (baseline) chlamydia infections (Manitoba: 8.86%(95%CI 7.15–10.75); Denmark: 3.84%(3.26–4.45); screened-arm POPI-RCT: 0.99%(0.00–29.06)). In the absence of active chlamydia treatment 26.44%(11.57–46.32) of PID at 12-months was attributable to untreated (baseline) chlamydia infections (deferred-arm POPI-RCT). The PEFs suggest that eradicating baseline chlamydia infections could prevent 484 cases of PID at 12-months per 100,000 women in the untreated setting and 13–184 cases of PID per 100,000 tested women in the presence of testing and treatment. Conclusion Testing and treating chlamydia reduced the PEF of chlamydia on PID by 65% compared to the untreated setting. But in the presence of testing and treatment over 90% of PID could not be attributed to a baseline chlamydia infection. More information is needed about the aetiology of PID to develop effective strategies for improving the reproductive health of women. PMID:28199392
Alahakoon, A U; Oey, I; Silcock, P; Bremer, P
2017-10-01
Brisket is a low value/tough meat cut that contains a large amount of connective tissue. Conversion of collagen into gelatin during heating reduces the toughness of the connective tissue however this conversion is slow at low cooking temperatures (around 60°C). The objective of this project was to determine the ability of pulsed electric field (PEF) processing to reduce the thermal stability of connective tissue. To achieve this, a novel model system was designed in which connective tissue obtained from beef deep pectotalis muscle (brisket) was exposed to PEF at combinations of electric field strength (1.0 and 1.5kV/cm) and specific energy (50 and 100kJ/kg) within an agar matrix at electrical conductivities representing the electrical conductivity found in brisket. Differential scanning calorimetry showed that PEF treatment significantly (p<0.05) decreased the denaturation temperature of connective tissue compared to untreated samples. Increasing electric field strength and the specific energy increased the Ringer soluble collagen fraction. PEF treated samples showed higher solubilization compared to the untreated samples at both 60°C and 70°C in heat solubility test. SEM examination of PEF treated (at 1.5kV/cm and 100kJ/kg) and untreated samples revealed that PEF appeared to increase the porosity of the connective tissue structure. These finding suggest that PEF processing is a technology that could be used to improve the tenderness and decrease the cooking time of collagen rich, meat cuts. Copyright © 2017 Elsevier Ltd. All rights reserved.
Moreira, Francisca C; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P
2015-05-15
Apart from a high biodegradable fraction consisting of organic acids, sugars and alcohols, winery wastewaters exhibit a recalcitrant fraction containing high-molecular-weight compounds as polyphenols, tannins and lignins. In this context, a winery wastewater was firstly subjected to a biological oxidation to mineralize the biodegradable fraction and afterwards an electrochemical advanced oxidation process (EAOP) was applied in order to mineralize the refractory molecules or transform them into simpler ones that can be further biodegraded. The biological oxidation led to above 97% removals of dissolved organic carbon (DOC), chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5), but was inefficient on the degradation of a bioresistant fraction corresponding to 130 mg L(-1) of DOC, 380 mg O2 L(-1) of COD and 8.2 mg caffeic acid equivalent L(-1) of total dissolved polyphenols. Various EAOPs such as anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) were then applied to the recalcitrant effluent fraction using a 2.2 L lab-scale flow plant containing an electrochemical cell equipped with a boron-doped diamond (BDD) anode and a carbon-PTFE air-diffusion cathode and coupled to a photoreactor with compound parabolic collectors (CPCs). The influence of initial Fe(2+) concentration and current density on the PEF process was evaluated. The relative oxidative ability of EAOPs increased in the order AO-H2O2 < EF < PEF ≤ SPEF. The SPEF process using an initial Fe(2+) concentration of 35 mg L(-1), current density of 25 mA cm(-2), pH of 2.8 and 25 °C reached removals of 86% on DOC and 68% on COD after 240 min, regarding the biologically treated effluent, along with energy consumptions of 45 kWh (kg DOC)(-1) and 5.1 kWh m(-3). After this coupled treatment, color, odor, COD, BOD5, NH4(+), NO3(-) and SO4(2-) parameters complied with the legislation targets and, in addition, a total dissolved polyphenols content of 0.35 mg caffeic acid equivalent L(-1) was found. Respirometry tests revealed low biodegradability enhancement along the SPEF process. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sun, Louise Y; Tu, Jack V; Bader Eddeen, Anan; Liu, Peter P
2018-06-16
Heart failure (HF) with reduced ejection fraction (rEF) is a widely regarded prognosticator after coronary artery bypass grafting. HF with preserved ejection fraction (pEF) accounts for up to half of all HF cases and is associated with considerable morbidity and mortality in hospitalized cohorts. However, HFpEF outcomes have not been elucidated in cardiac surgical patients. We investigated the prevalence and outcomes of HFpEF and HFrEF in women and men following coronary artery bypass grafting. We conducted a retrospective cohort study in Ontario, Canada, between October 1, 2008, and March 31, 2015, using Cardiac Care Network and Canadian Institute of Health Information data. HF is captured through a validated population-based database of all Ontarians with physician-diagnosed HF. We defined pEF as ejection fraction ≥50% and rEF as ejection fraction <50%. The primary outcome was all-cause mortality. Analyses were stratified by sex. Mortality rates were calculated using Kaplan-Meier method. The relative hazard of death was assessed using multivariable Cox proportional hazard models. Of 40 083 patients (20.6% women), 55.5% had pEF without HF, 25.7% had rEF without HF, 6.9% had HFpEF, and 12.0% had HFrEF. Age-standardized HFpEF mortality rates at 4±2 years of follow-up were similar in women and men. HFrEF standardized HFpEF mortality rates were higher in women than men. We found a higher prevalence and poorer prognosis of HFpEF in women. A history of HF was a more important prognosticator than ejection fraction. Preoperative screening and extended postoperative follow-up should be focused on women and men with HF rather than on rEF alone. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Berry, C; Poppe, K K; Gamble, G D; Earle, N J; Ezekowitz, J A; Squire, I B; McMurray, J J V; McAlister, F A; Komajda, M; Swedberg, K; Maggioni, A P; Ahmed, A; Whalley, G A; Doughty, R N; Tarantini, L
2016-06-01
Anaemia is common among patients with heart failure (HF) and is an important prognostic marker. We sought to determine the prognostic importance of anaemia in a large multinational pooled dataset of prospectively enrolled HF patients, with the specific aim to determine the prognostic role of anaemia in HF with preserved and reduced ejection fraction (HF-PEF and HF-REF, respectively). Individual person data meta-analysis. Patients with haemoglobin (Hb) data from the MAGGIC dataset were used. Anaemia was defined as Hb < 120 g/l in women and <130 g/l in men. HF-PEF was defined as EF ≥ 50%; HF-REF was EF < 50%. Cox proportional hazard modelling, with adjustment for clinically relevant variables, was undertaken to investigate factors associated with 3-year all-cause mortality. Thirteen thousand two hundred and ninety-five patients with HF from 19 studies (9887 with HF-REF and 3408 with HF-PEF). The prevalence of anaemia was similar among those with HF-REF and HF-PEF (42.8 and 41.6% respectively). Compared with patients with normal Hb values, those with anaemia were older, were more likely to have diabetes, ischaemic aetiology, New York Heart Association class IV symptoms, lower estimated glomerular filtration rate and were more likely to be taking diuretic and less likely to be taking a beta-blocker. Patients with anaemia had higher all-cause mortality (adjusted hazard ratio [aHR] 1.38, 95% confidence interval [CI] 1.25-1.51), independent of EF group: aHR 1.67 (1.39-1.99) in HF-PEF and aHR 2.49 (2.13-2.90) in HF-REF. Anaemia is an adverse prognostic factor in HF irrespective of EF. The prognostic importance of anaemia was greatest in patients with HF-REF. © The Author 2015. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Deng, Yunxia; Shi, Dongxia; Yin, Zhongqiong; Guo, Jianhong; Jia, Renyong; Xu, Jiao; Song, Xu; Lv, Cheng; Fan, Qiaojia; Liang, Xiaoxia; Shi, Fei; Ye, Gang; Zhang, Wei
2012-04-01
The petroleum ether extract of neem oil and its four fractions separated by column chromatography was diluted at different concentrations with liquid paraffin. The acaricidal bioassay was conducted using a dipping method. The results indicated that the median lethal concentration (LC50) of the petroleum ether extract (at the concentration of 500.0ml/l) was 70.9ml/l, 24h after treatment. At concentrations of 500.0, 250.0, 125.0, 62.5 and 31.2ml/l, the median lethal times (LT50) of the petroleum ether extract were 8.7, 8.8, 10.8, 11.5 and 13.1h, respectively. Thin-layer chromatography (TLC) showed that the petroleum ether extract of neem oil separated into four fractions (F1-F4). Acaricidal activity of 68.3% and 100.0% in the F2 and F4 was confirmed. These results suggest that petroleum ether extracts of neem oil and its four fractions possess useful acaricidal activity in vitro. Copyright © 2012 Elsevier Inc. All rights reserved.
Santos, Francisco José Borges Dos; Moura, Dinara Jaqueline; Péres, Valéria Flores; Sperotto, Angelo Regis de Moura; Caramão, Elina Bastos; Cavalcante, Ana Amélia de Carvalho Melo; Saffi, Jenifer
2012-12-18
Bauhinia platypetala Burch. is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates the safety of its use. The aim of this study was to investigate the safety of the ethanolic extract and the ethereal fraction of B. platypetala leaves. The identification of chemical compounds from the B. platypetala ethanolic extract and its ethereal fraction was performed by GC/MS and ESI-MS/MS. The plant's toxicological, cytotoxic, mutagenic and genotoxic properties were determined in Saccharomyces cerevisiae strains and V79 cell culture by survival assays and comet assay. The major compound identified in the B. platypetala ethanolic extract is palmitic acid, kaempferitirin and quercitrin, while the B. platypetala ethereal fraction was found to be rich in phytol, gamma-sitosterol and vitamin E. Moreover, the results indicated that the B. platypetala ethanolic extract has an anti-oxidative effect against H(2)O(2) in yeast. In addition, the B. platypetala ethanolic extract did not induce mutagenic effects on the S. cerevisiae N123 strain, but the ethereal fraction of B. platypetala at higher concentrations (250-500 μg/mL) induced cytotoxicity and mutagenicity. A slight cytotoxic effect was observed in mammalian V79 cells; however, both the B. platypetala ethanolic extract and its ethereal fraction were able to induce DNA strand breaks in V79 cells, as detected by the alkaline comet assay. The B. platypetala ethanolic extract has antioxidant action and showed absence of mutagenic effects in yeast S. cerevisiae. On the other hand B. platypetala ethereal fraction is mutagenic and does not show antioxidant activity in yeast. In mammalian cells B. platypetala ethanolic extract and it's ethereal fraction induce cyotoxic and genotoxic action. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
McAlister, Finlay A; Ezekowitz, Justin; Tarantini, Luigi; Squire, Iain; Komajda, Michel; Bayes-Genis, Antoni; Gotsman, Israel; Whalley, Gillian; Earle, Nikki; Poppe, Katrina K; Doughty, Robert N
2012-05-01
Prior studies in heart failure (HF) have used the Modification of Diet in Renal Disease (MDRD) equation to calculate estimated glomerular filtration rate (eGFR). The Chronic Kidney Disease-Epidemiology Collaboration Group (CKD-EPI) equation provides a more-accurate eGFR than the MDRD when compared against the radionuclide gold standard. The prevalence and prognostic import of renal dysfunction in HF if the CKD-EPI equation is used rather than the MDRD is uncertain. We used individual patient data from 25 prospective studies to stratify patients with HF by eGFR using the CKD-EPI and the MDRD equations and examined survival across eGFR strata. In 20 754 patients (15 962 with HF with reduced ejection fraction [HF-REF] and 4792 with HF with preserved ejection fraction [HF-PEF]; mean age, 68 years; deaths per 1000 patient-years, 151; 95% CI, 146-155), 10 589 (51%) and 11 422 (55%) had an eGFR <60 mL/min using the MDRD and CKD-EPI equations, respectively. Use of the CKD-EPI equation resulted in 3760 (18%) patients being reclassified into different eGFR risk strata; 3089 (82%) were placed in a lower eGFR category and exhibited higher all-cause mortality rates (net reclassification improvement with CKD-EPI, 3.7%; 95% CI, 1.5%-5.9%). Reduced eGFR was a stronger predictor of all-cause mortality in HF-REF than in HF-PEF. Use of the CKD-EPI rather than the MDRD equation to calculate eGFR leads to higher estimates of renal dysfunction in HF and a more-accurate categorization of mortality risk. Renal function is more closely related to outcomes in HF-REF than in HF-PEF.
Larvicidal Activity of Centaurea bruguierana ssp. belangerana Against Anopheles stephensi Larvae.
Khanavi, Mahnaz; Rajabi, Afsaneh; Behzad, Masoud; Hadjiakhoondi, Abbas; Vatandoost, Hassan; Abaee, Mohammad Reza
2011-01-01
In this study, the total 80% of MeOH extract and also petroleum ether, CHCl3, EtOAc, n-BuOH, and the remaining MeOH fractions obtained by solvent-solvent fractionation of the whole flowering samples of Centaurea bruguierana (DC.) Hand.-Mzt. ssp. belangerana (DC.) Bornm. (Asteraceae), namely "Baad-Avard", collected from Borazjan in Bushehr Province (Bushehr, Iran) were investigated for larvicidal activity against malaria vector, Anopheles stephensi Liston, according to WHO methods. The mortality rate of total extract and petroleum ether fraction in concentration of 40 ppm were 28% and 86% respectively and the other fractions were inactive. The probit regression analysis for the dose-response to petroleum ether fraction treatment of larvae exhibited the LC50 and LC90 values of 15.7 ppm and 48.3 ppm, respectively. As results showed, the larvicidal activity of the petroleum ether fraction would be due to the nonpolar compounds in the plant which further isolation and purification would obtain the more active compounds in lower concentrations useful for preparation of biological insecticides.
Larvicidal Activity of Centaurea bruguierana ssp. belangerana Against Anopheles stephensi Larvae
Khanavi, Mahnaz; Rajabi, Afsaneh; Behzad, Masoud; Hadjiakhoondi, Abbas; Vatandoost, Hassan; Abaee, Mohammad Reza
2011-01-01
In this study, the total 80% of MeOH extract and also petroleum ether, CHCl3, EtOAc, n-BuOH, and the remaining MeOH fractions obtained by solvent-solvent fractionation of the whole flowering samples of Centaurea bruguierana (DC.) Hand.-Mzt. ssp. belangerana (DC.) Bornm. (Asteraceae), namely “Baad-Avard”, collected from Borazjan in Bushehr Province (Bushehr, Iran) were investigated for larvicidal activity against malaria vector, Anopheles stephensi Liston, according to WHO methods. The mortality rate of total extract and petroleum ether fraction in concentration of 40 ppm were 28% and 86% respectively and the other fractions were inactive. The probit regression analysis for the dose-response to petroleum ether fraction treatment of larvae exhibited the LC50 and LC90 values of 15.7 ppm and 48.3 ppm, respectively. As results showed, the larvicidal activity of the petroleum ether fraction would be due to the nonpolar compounds in the plant which further isolation and purification would obtain the more active compounds in lower concentrations useful for preparation of biological insecticides. PMID:24250419
Geographic differences in heart failure trials.
Ferreira, João Pedro; Girerd, Nicolas; Rossignol, Patrick; Zannad, Faiez
2015-09-01
Randomized controlled trials (RCTs) are essential to develop advances in heart failure (HF). The need for increasing numbers of patients (without substantial cost increase) and generalization of results led to the disappearance of international boundaries in large RCTs. The significant geographic differences in patients' characteristics, outcomes, and, most importantly, treatment effect observed in HF trials have recently been highlighted. Whether the observed regional discrepancies in HF trials are due to trial-specific issues, patient heterogeneity, structural differences in countries, or a complex interaction between factors are the questions we propose to debate in this review. To do so, we will analyse and review data from HF trials conducted in different world regions, from heart failure with preserved ejection fraction (HF-PEF), heart failure with reduced ejection fraction (HF-REF), and acute heart failure (AHF). Finally, we will suggest objective and actionable measures in order to mitigate regional discrepancies in future trials, particularly in HF-PEF where prognostic modifying treatments are urgently needed and in which trials are more prone to selection bias, due to a larger patient heterogeneity. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.
[Study on the constituents of petroleum ether fraction of Buxus microphylla].
Dai, Zhi-Kai; Liang, Jun; Su, Xiao-Jian; Xu, Qing; Zhang, Hui-Qin
2009-07-01
To study the chemical constituents from the petroleum ether fraction of Buxus microphylla. The petroleum ether fraction of Buxus microphylla was isolated and identified by silica gel column chromatography. And the anticancer activity of different chemical constituents was measured by MTT reduction test. Eight compounds were isolated and identified as lupeol (1), butulin (3), beta-sitosterol (4), stigmasterol (5), dibutyl phthalate (6), 3beta, 30-dihydroxy-lup-20 (29) ene (7), daucosterol (8). Compound 7 inhibited KB cells' proliferation in a dose-dependent manner. Compounds 2 - 5, 7, 8 are isolated from this genus for the first time. Compound 7 has certainly anticancer effects.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.
1984-05-08
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, Jr., Lawrence A.; Jones, Jr., Edward M.; Hearn, Dennis
1984-01-01
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150.degree. to 250.degree. F. at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C.sub.3 to C.sub.6 and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom.
Yucra, Sandra; Gasco, Manuel; Rubio, Julio; Nieto, Jessica; Gonzales, Gustavo F
2008-05-01
To evaluate the effect of different fractions of Black Maca (Lepidium meyenii), obtained from the hydroalcoholic extract, on spermatogenesis. Animal study. Animal and laboratory facilities at a university. Forty two adult male rats from the Holtzman strain (3 months old). Hydroalcoholic extract of Black Maca was partitioned with the following solvents: petroleum ether, chloroform, ethyl acetate, n-butanol, and water to obtain each fraction. Forty-two rats were divided in different groups according the fraction administered and vehicle. The hydroalcoholic extract of Black Maca and its fractions and vehicle were given orally by gavage for 7 days. Daily sperm production, epididymal sperm count, and sperm count in the vas deferens. Daily sperm production was higher in the ethyl acetate group compared with all other groups. The epididymal sperm count was higher in rats treated with ethyl acetate fraction compared with rats treated with vehicle (control), petroleum ether, n-butanol, or water fractions. The sperm count in vas deferens was lower in rats treated with ethyl acetate, petroleum ether, or water fractions compared with the control group; thus, the sperm count in vas deferens in rats treated with chloroform and n-butanol fractions was higher than in the petroleum ether group. The greatest effect on spermatogenesis was observed in the ethyl acetate fraction from the hydroalcoholic extract of Black Maca, suggesting that the compounds related to the beneficial effect on sperm production of Black Maca are presented in this fraction. Antioxidant components could play a role in the effect of increased epididymal sperm concentration observed in the model.
2014-01-01
Background Antioxidant compounds like phenols and flavonoids scavenge free radicals and thus inhibit the oxidative mechanisms that lead to control degenerative and other diseases. The aim of this study was to investigate the antioxidant activity in vitro, total phenolic and flavonoid contents in ethanol extracts and fractions of Crescentia cujete leaves and stem bark. Methods Crescentia cujete leaves and bark crude ethanol extract (CEE) and their partitionates petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF) and aqueous (AQF) were firstly prepared. Different established testing methods, such as 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical, ferric reducing power (FRP), and total antioxidant capacity (TAC) assays were used to detect the antioxidant activity. Further, the total yield, total phenolic (TPC) and total flavonoid contents (TFC) of CEE and all the fractions were determined. Ethanol extracts of both leaves and stem bark were also subjected to preliminary phytochemical screening to detect the presence of secondary metabolites, using standard phytochemical methods (Thin layer chromatography and spray reagents). Results Phytochemical screening of crude ethanol extract of both leaves and stem bark revealed the presence of steroids, flavonoids, saponins, tannins, glycosides and terpenoids. All the fractions and CEE of leaves and bark exhibited antioxidant activities, however, EAF of leaves showing the highest antioxidant activity based on the results of DPPH, FRP and TAC assay tests. The above fraction has shown the significant DPPH scavenging activity (IC50 = 8.78 μg/ml) when compared with standard ascorbic acid (IC50 =7.68 μg/ml). The TAC and FRP activities increased with increasing crude extract/fractions content. The TPC (371.23 ± 15.77 mg GAE/g extract) and TFC (144.64 ± 5.82 mg QE/g extract) of EAF of leaves were found significantly higher as compared to other solvent fractions for both leaves and bark. TPC were highly correlated with the antioxidant activity (R2 = 0.9268 and 0.8515 in DPPH test for leaves and bark, respectively). Conclusion The results of the study show that leaves of C. cujete possesses significant free radical scavenging properties compared with stem bark and a clear correlation exists between the antioxidant activity and phenolic content. PMID:24495381
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Phillips Petroleum Co. is poised to license its high conversion process to produce fuel ethers for blending in reformulated gasolines. The technology has been proven in a Phillips semiworks at Bartlesville, Okla. The process can produce methyl tertiary butyl ether, ethyl tertiary butyl ether, tertiary amyl methyl ether, or tertiary amyl ethyl ether with typical refinery process equipment and techniques. Phillips said it can achieve conversion levels of 92-99%, depending on the ether. The ether produced is determined by which hydrocarbon fraction is used for feedstock and which alcohol is chosen for reaction. The process is described.
NASA Astrophysics Data System (ADS)
Kuz'mina, I. A.; Usacheva, T. R.; Kuz'mina, K. I.; Volkova, M. A.; Sharnin, V. A.
2015-01-01
The Gibbs energies of the transfer of 18-crown-6 ether from methanol to its mixtures with acetonitrile (χAN = 0.0-1.0 mole fraction) are determined by means of interphase distribution at 298 K. The effect the solvent composition has on the thermodynamic characteristics of the solvation of 18-crown-6 ether is analyzed. An increase in the content of acetonitrile in the mixed solvent enhances the solvation of crown ether due to changes in the energy of the solution. Resolvation of the macrocycle is assumed to be complete at acetonitrile concentrations higher than 0.6 mole fraction.
Antimicrobial and cytotoxic constituents from leaves of Sapium baccatum.
Ahmed, Yunus; Sohrab, Md Hossain; Al-Reza, Sharif M; Tareq, Faqir Shahidulla; Hasan, Choudhury M; Sattar, M A
2010-02-01
Six compounds, namely, Lupeol (1), Betulin (2), beta-Taraxerol (3), Taraxerone (4), Stigmasterol (5) and beta-Sitosterol (6) were isolated from the petroleum ether extract of the leaves of Sapium baccatum based on spectroscopic evidence. Lupeol (1), Betulin (2) and Stigmasterol (5) were isolated for the first time from this plant. The cytotoxic potential of the different solvent extracts (methanol, petroleum ether, carbon-tetrachloride and dichloromethane); six column fractions (F-4, F-7, F-10, F-12, F-18 and F-22) of petroleum ether extract and three pure compounds 1, 4 and 6 were determined by using brine shrimp lethality bioassay. The LC50 of all the tested samples were showed to be lethal to brine shrimp nauplii. However, petroleum ether, carbon-tetrachloride extract, column fractions F-4 and F-18 of petroleum ether extract and pure compound 6 showed quite potent activity in brine shrimp lethality bioassay with LC50 1.33, 1.35, 1.40, 1.58 and 1.58 microg/ml, respectively. These result suggested that they might be contain antitumor or pesticidal activity. Further, the methanol extract and four column fractions (F-7, F-12, F-18 and F-22) of petroleum ether showed significant activity against the tested microorganisms. Copyright 2009 Elsevier Ltd. All rights reserved.
Li, Dong; Secher, Jan O.; Mashayekhi, Kaveh; Nielsen, Troels T.; Hyttel, Poul; Freude, Kristine K.
2017-01-01
ABSTRACT Previous research has shown that a subpopulation of cells within cultured human dermal fibroblasts, termed multilineage-differentiating stress enduring (Muse) cells, are preferentially reprogrammed into induced pluripotent stem cells. However, controversy exists over whether these cells are the only cells capable of being reprogrammed from a heterogeneous population of fibroblasts. Similarly, there is little research to suggest such cells may exist in embryonic tissues or other species. To address if such a cell population exists in pigs, we investigated porcine embryonic fibroblast populations (pEFs) and identified heterogeneous expression of several key cell surface markers. Strikingly, we discovered a small population of stage-specific embryonic antigen 1 positive cells (SSEA-1+) in Danish Landrace and Göttingen minipig pEFs, which were absent in the Yucatan pEFs. Furthermore, reprogramming of SSEA-1+ sorted pEFs led to higher reprogramming efficiency. Subsequent transcriptome profiling of the SSEA-1+ vs. the SSEA-1neg cell fraction revealed highly comparable gene signatures. However several genes that were found to be upregulated in the SSEA-1+ cells were similarly expressed in mesenchymal stem cells (MSCs). We therefore termed these cells SSEA-1 Expressing Enhanced Reprogramming (SEER) cells. Interestingly, SEER cells were more effective at differentiating into osteocytes and chondrocytes in vitro. We conclude that SEER cells are more amenable for reprogramming and that the expression of mesenchymal stem cell genes is advantageous in the reprogramming process. This data provides evidence supporting the elite theory and helps to delineate which cell types and specific genes are important for reprogramming in the pig. PMID:28426281
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morotomi-Yano, Keiko; Akiyama, Hidenori; Yano, Ken-ichi, E-mail: yanoken@kumamoto-u.ac.jp
Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in severalmore » cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs.« less
Peak flowmeter resistance decreases peak expiratory flow in subjects with COPD.
Miller, M R; Pedersen, O F
2000-07-01
Previous studies have shown that the added resistance of a mini-Wright peak expiratory flow (PEF) meter reduced PEF by approximately 8% in normal subjects because of gas compression reducing thoracic gas volume at PEF and thus driving elastic recoil pressure. We undertook a body plethysmographic study in 15 patients with chronic obstructive pulmonary disease (COPD), age 65.9 +/- 6.3 yr (mean +/- SD, range 53-75 yr), to examine whether their recorded PEF was also limited by the added resistance of a PEF meter. The PEF meter increased alveolar pressure at PEF (Ppeak) from 3.7 +/- 1.4 to 4.7 +/- 1.5 kPa (P = 0.01), and PEF was reduced from 3.6 +/- 1.3 l/s to 3.2 +/- 0.9 l/s (P = 0.01). The influence of flow limitation on PEF and Ppeak was evaluated by a simple four-parameter model based on the wave-speed concept. We conclude that added external resistance in patients with COPD reduced PEF by the same mechanisms as in healthy subjects. Furthermore, the much lower Ppeak in COPD patients is a consequence of more severe flow limitation than in healthy subjects and not of deficient muscle strength.
Bouti, Khalid; Benamor, Jouda; Bourkadi, Jamal Eddine
2017-08-01
Peak Expiratory Flow (PEF) has never been characterised among healthy Moroccan school children. To study the relationship between PEF and anthropometric parameters (sex, age, height and weight) in healthy Moroccan school children, to establish predictive equations of PEF; and to compare flowmetric and spirometric PEF with Forced Expiratory Volume in 1 second (FEV1). This cross-sectional study was conducted between April, 2016 and May, 2016. It involved 222 (122 boys and 100 girls) healthy school children living in Ksar el-Kebir, Morocco. We used mobile equipments for realisation of spirometry and peak expiratory flow measurements. SPSS (Version 22.0) was used to calculate Student's t-test, Pearson's correlation coefficient and linear regression. Significant linear correlation was seen between PEF, age and height in boys and girls. The equation for prediction of flowmetric PEF in boys was calculated as 'F-PEF = -187+ 24.4 Age + 1.61 Height' (p-value<0.001, r=0.86), and for girls as 'F-PEF = -151 + 17Age + 1.59Height' (p-value<0.001, r=0.86). The equation for prediction of spirometric PEF in boys was calculated as 'S-PEF = -199+ 9.8Age + 2.67Height' (p-value<0.05, r=0.77), and for girls as 'S-PEF = -181 + 8.5Age + 2.5Height' (p-value<0.001, r=0.83). The boys had higher values than the girls. The performance of the Mini Wright Peak Flow Meter was lower than that of a spirometer. Our study established PEF predictive equations in Moroccan children. Our results appeared to be reliable, as evident by the high correlation coefficient in this sample. PEF can be an alternative of FEV1 in centers without spirometry.
Deashing macroalgae biomass by pulsed electric field treatment.
Robin, Arthur; Sack, Martin; Israel, Alvaro; Frey, Wolfgang; Müller, Georg; Golberg, Alexander
2018-05-01
Among all biomass constituents, the ashes are major hurdles for biomass processing. Ashes currently have low market value and can make a non-negligible fraction of the biomass dry weight significantly impacting its further processing by degrading equipment, lowering process yield, inhibiting reactions and decreasing products qualities. However, most of the current treatments for deashing biomass are of poor efficiency or industrial relevance. This work is the first report on the use of Pulsed Electric Field (PEF) to enhance deashing of biomass from a high ash content green marine macroalga, Ulva sp., using hydraulic pressing. By inducing cell permeabilization of the fresh biomass, PEF was able to enhance the ash extraction from 18.4% (non-treated control) to 37.4% of the total ash content in average, significantly enhancing the extraction of five of the major ash elements (K, Mg, Na, P and S) compared to pressing alone. Copyright © 2018 Elsevier Ltd. All rights reserved.
Antimicrobial activities of the rhizome extract of Zingiber zerumbet Linn.
Kader, Golam; Nikkon, Farjana; Rashid, Mohammad Abdur; Yeasmin, Tanzima
2011-10-01
To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet (Z. zerumbet) (L.) Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and fungi. The fresh rhizomes of Zingiber zerumbet were extracted in cold with ethanol (4.0 L) after concentration. The crude ethanol extract was fractionated by petroleum ether and chloroform to form a suspension of ethanol extract (15.0 g), petroleum ether fraction (6.6 g) and chloroform soluble fraction (5.0 g). The crude ethanol extract and its petroleum ether and chloroform fractions were evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and three fungi by the disc diffusion method. Commercially available kanamycin (30 µg/disc) was used as standard disc and blank discs impregnated with the respective solvents were used as negative control. At a concentration of 400 µg/disc, all the samples showed mild to moderate antibacterial and antifungal activity and produced the zone of inhibition ranging from 6 mm to 10 mm. Among the tested samples, the crude ethanol extract showed the highest activity against Vibrio parahemolyticus (V. parahemolyticus). The minimum inhibitory concentration (MIC) of the crude ethanol extract and its fractions were within the value of 128-256 µg/mL against two Gram positive and four Gram negative bacteria and all the samples showed the lowest MIC value against V. parahemolyticus (128 µg/mL). It can be concluded that, potent antibacterial and antifungal phytochemicals are present in ethanol extract of Z. zerumbet (L).
Gas compression in lungs decreases peak expiratory flow depending on resistance of peak flowmeter.
Pedersen, O F; Pedersen, T F; Miller, M R
1997-11-01
It has recently been shown (O. F. Pedersen T. R. Rasmussen, O. Omland, T. Sigsgaard, P. H. Quanjer. and M. R. Miller. Eur. Respir. J. 9: 828-833, 1996) that the added resistance of a mini-Wright peak flowmeter decreases peak expiratory flow (PEF) by approximately 8% compared with PEF measured by a pneumotachograph. To explore the reason for this, 10 healthy men (mean age 43 yr, range 33-58 yr) were examined in a body plethysmograph with facilities to measure mouth flow vs. expired volume as well as the change in thoracic gas volume (Vb) and alveolar pressure (PA). The subjects performed forced vital capacity maneuvers through orifices of different sizes and also a mini-Wright peak flowmeter. PEF with the meter and other added resistances were achieved when flow reached the perimeter of the flow-Vb curves. The mini-Wright PEF meter decreased PEF from 11.4 +/- 1.5 to 10.3 +/- 1.4 (SD) l/s (P < 0.001), PA increased from 6.7 +/- 1.9 to 9.3 +/- 2.7 kPa (P < 0.001), an increase equal to the pressure drop across the meter, and caused Vb at PEF to decrease by 0.24 +/- 0.09 liter (P < 0.001). We conclude that PEF obtained with an added resistance like a mini-Wright PEF meter is a wave-speed-determined maximal flow, but the added resistance causes gas compression because of increased PA at PEF. Therefore, Vb at PEF and, accordingly, PEF decrease.
Frequency response of portable PEF meters.
Hankinson, J L; Das, M K
1995-08-01
Peak expiratory flow (PEF) is a dynamic parameter and therefore requires a measuring device with a high-frequency response. This study evaluated the frequency-response characteristics of eight commercially available PEF meters, using simulated forced-expiratory maneuvers with a computer-controlled mechanical pump. Three different PEF levels were used (200, 400, and 600 L/min) at six levels of harmonic-frequency content similar to those observed in human subjects. For waveforms with higher frequency content (at the high end or above the physiologic range), the Assess, Vitalograph, Pocket Peak, and Spir-O-Flow PEF meters all overread PEF (greater than 15% difference from target values) at all three PEF levels. These results suggest that the frequency response of PEF meters is an important consideration in the selection of such meters and should be included in device requirements. The current practice of using various levels of American Thoracic Society (ATS) waveform 24 with its low-frequency content may not adequately evaluate the frequency characteristics of PEF meters. An upper range (5% of the fundamental frequency) of 12 Hz, within the range observed in normal subjects, appears to be more practical than an upper limit of 20 Hz.
Ngan, Dai Hue; Hoai, Ho Thi Cam; Huong, Le Mai; Hansen, Poul Erik; Vang, Ole
2008-01-01
Five crude extracts were made from leaves and stems of Jasminum subtriplinerve Blume (Oleaceae) and investigated for antimicrobial, antioxidant and cytotoxic activities. The extractions were done with petroleum ether, ethyl acetate, ethanol, methanol or water. All extracts exhibited anti-bacterial activity except the water fraction. On the other hand, all extracts exhibit antioxidant activity except the petroleum ether fraction using the DPPH radical scavenging assay. Only the petroleum ether fraction showed a cytotoxicity activity against tested cell-lines, Hep-G2 and RD with IC(50) values of 19.2 and 20 microg mL(-1), respectively. From the petroleum ether and ethyl acetate extracts, two triterpenes namely 3beta-acetyl-oleanolic acid and lup-20-en-3beta-ol and a sterol, stigmast-5-en-3beta-ol were isolated. The structure of those compounds were elucidated by spectrometric methods IR, MS, 1D-NMR, 2D-NMR and simulated ACD/NMR spectra. The data presented here indicate that J. subtriplinerve do contain compounds with interesting biological activity.
NASA Astrophysics Data System (ADS)
Takamasa, OKUMURA; Taro, YAEGASHI; Takahiro, FUJIWARA; Katsuyuki, TAKAHASHI; Koichi, TAKAKI; Tomo, KUDO
2018-04-01
A pulsed electric field (PEF) was applied to unpasteurized sake at constant temperatures, at which α-amylase was not inactivated. We adjusted the input energy to be identical for the temperatures by changing the number of PEF application, because the current significantly increased with the temperature, even the amplitude of the applied voltage was identical. As a result, the α-amylase was seemed to be inactivated by PEF application, not due to thermal effect. The glucoamylase was significantly inactivated by PEF. Moreover, the acid carboxypeptidase was inactivated by PEF at 4 °C but significantly activated at 25 °C. These results show that the sensitivity of enzyme to PEF application differs depending on the types of enzyme and treatment temperature. On the other hand, the colony number of bacteria was remarkably decreased, but the amount of the volatile flavor compounds was not decreased by PEF application.
Liu, Tingting; Burritt, David John; Eyres, Graham T; Oey, Indrawati
2018-04-15
The aims of this research were to investigate if pulsed electric field (PEF) treatments caused cellular/structural alterations in Oxalis tuberosa (oca) tubers and if PEF treatment could reduce tuber oxalate levels. Whole oca tubers were treated with PEF at different electric field strengths up to 1.2 kV/cm. PEF treatments above 0.5 kV/cm caused tubers to soften, but differences in the electrical properties of the tuber tissues led to an uneven PEF effect with the tuber inner cores softening more than the middle regions. Cell viability tests confirmed the unevenness of the PEF effect, however PEF caused no changes in overall tuber/tissue structure. Even at high electric field strengths the cell remained largely intact and most starch grains were retained within the cells. Despite the retention of starch, PEF treatment reduced tuber oxalate contents by almost 50% in some tissues and could potentially aid the development of low oxalate oca-based foods. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effect of Pulsed Electric Field on Membrane Lipids and Oxidative Injury of Salmonella typhimurium
Yun, Ou; Zeng, Xin-An; Brennan, Charles S.; Han, Zhong
2016-01-01
Salmonella typhimurium cells were subjected to pulsed electric field (PEF) treatment at 25 kV/cm for 0–4 ms to investigate the effect of PEF on the cytoplasmic membrane lipids and oxidative injury of cells. Results indicated that PEF treatment induced a decrease of membrane fluidity of Salmonella typhimurium (S. typhimuriumi), possibly due to the alterations of fatty acid biosynthesis-associated gene expressions (down-regulation of cfa and fabA gene expressions and the up-regulation of fabD gene expression), which, in turn, modified the composition of membrane lipid (decrease in the content ratio of unsaturated fatty acids to saturated fatty acids). In addition, oxidative injury induced by PEF treatment was associated with an increase in the content of malondialdehyde. The up-regulation of cytochrome bo oxidase gene expressions (cyoA, cyoB, and cyoC) indicated that membrane damage was induced by PEF treatment, which was related to the repairing mechanism of alleviating the oxidative injury caused by PEF treatment. Based on these results, we achieved better understanding of microbial injury induced by PEF, suggesting that micro-organisms tend to decrease membrane fluidity in response to PEF treatment and, thus, a greater membrane fluidity might improve the efficiency of PEF treatment to inactivate micro-organisms. PMID:27556460
NASA Astrophysics Data System (ADS)
Guo, Jinsong; Dang, Jie; Wang, Kaile; Zhang, Jue; Fang, Jing
2018-05-01
Candida albicans is the leading human fungal pathogen that causes many life-threatening infections. Notably, the current clinical trial data indicate that Candida species shows the emerging resistance to anti-fungal drugs. The aim of this study was to evaluate the antifungal effects of nanosecond pulsed electric fields (nsPEFs) as a novel drug-free strategy in vitro. In this study, we investigated the inactivation and permeabilization effects of C. albicans under different nsPEFs exposure conditions (100 pulses, 100 ns in duration, intensities of 20, 40 kV cm‑1). Cell death was studied by annexin-V and propidium iodide staining. The changes of intracellular Ca2+ concentration after nsPEFs treatment were observed using Fluo-4 AM. Results show that C. albicans cells and biofilms were both obviously inhibited and destroyed after nsPEFs treatment. Furthermore, C. albicans cells were significantly permeabilized after nsPEFs treatment. Additionally, nsPEFs exposure led to a large amount of DNA and protein leakage. Importantly, nsPEFs induced a field strength-dependent apoptosis in C. albicans cells. Further experiments revealed that Ca2+ involved in nsPEFs induced C. albicans apoptosis. In conclusion, this proof-of-concept study provides a potential alternative drug-free strategy for killing pathogenic Candida species.
Ritti-Dias, Raphael Mendes; Cucato, Gabriel Grizzo; de Mello Franco, Fábio Gazelato; Cendoroglo, Maysa Seabra; Nasri, Fábio; Monteiro-Costa, Maria Luiza; de Carvalho, José Antonio Maluf; de Matos, Luciana Diniz Nagem Janot
2016-09-01
The aim of the present study was to verify if there is sex difference in the associations among handgrip strength, peak expiratory flow (PEF) and timed up and go (TUG) test results. The sample included 288 consecutive elderly men (n=93) and women (n=195). Functional capacity was measured using the TUG test, and muscle strength was measured based on handgrip. Moreover, as a measure of current health status, PEF was evaluated. Linear regression procedures were performed to analyze the relationships between handgrip and both PEF and TUG test results, with adjustment for confounders, and to identify the possible mediating role of PEF in the association between handgrip strength and TUG test results. In men, handgrip strength was associated with both PEF and TUG performance (p<0.01). After adjustment for PEF, the relationship between handgrip strength and TUG performance remained significant. In women, handgrip strength was also associated with both PEF and TUG performance (p<0.01). However, after adjustment for PEF, the relationship between handgrip strength and TUG performance was no longer significant. Mobility in the elderly is sex dependent. In particular, PEF mediates the relationship between handgrip strength and TUG performance in women, but not in men.
Walkling-Ribeiro, Markus; Anany, Hany; Griffiths, Mansel W
2015-01-01
Pulsed electric fields (PEF), heat-assisted PEF (H-PEF), and virulent bacteriophage (VP) are non-thermal techniques for pathogen inactivation in liquids that were investigated individually, and in combination (PEF/VP, H-PEF/VP) to control enterohemorrhagic Escherichia coli (EHEC) O157:H7 in Luria-Bertani broth (LBB) and Ringer's solution (RS). Treated cells were subsequently incubated at refrigeration (4°C) and temperature-abuse conditions (12°C) for 5 days. When EHEC cells grown in LBB were subjected to non-thermal processing and subsequently stored at 12°C for 5 days, reductions in count of between 0.1 and 0.6 log cycles were observed and following storage at 4°C the decrease in counts varied between 0.2 and 1.1 log10 . For bacteria cells suspended in RS values ranged from 0.1 to ≥3.9 log cycles at both storage temperatures. The most effective treatments were H-PEF and H-PEF/VP, both producing a >3.4 log cycle reduction of cells suspended in non-nutrient RS. Analysis of EHEC recovery on selective and non-selective media indicated no occurrence of sub-lethal damage for VP, PEF/VP, and H-PEF/VP-treated cells. The findings indicate that combining PEF and lytic phage may represent a suitable alternative to conventional fluid decontamination following further process optimization. © 2014 American Institute of Chemical Engineers.
Impact of PEF and thermal processing on apple juice shelf life
Torkamani, AE
2011-01-01
Background and Objectives Pulsed electric field (PEF) is a novel emerging technology which is believed to have the potential to substitute conventional thermal pasteurization (HTST). In the current study PEF was compared with HTST based on microbial inactivation and quality attributes. Materials and Methods Juice was prepared by extracting it from Semirum apples. They were chilled to 4°C over night. Then were divided into two lots, one was treated by PEF and the other by HTST. The treated juices were cultured on tryphtic soy broth (TSB) and results were recorded for 168 days. Quality changes were characterized by color and sensory test. Color changes were quantified using Hunter Lab equipment and equation. Sensory changes were evaluated by test panelists. Results: Using selective media E. Coli was enumerated, the total count of the organism was noticeably lower than PEF treated specimen and after 168. The count didn't reach the initial population. Whereas in PEF treated juice bacterial count bounced back to the initial count and exceeds. Results from Hunter Lab indicated a of 3.04 and 3.08 system for PEF and HTST treated juices. Sensory panel showed that PEF is superior to thermal treatment. Conclusion The study indicated HTST is more suitable based on food safety encounters. However PEF treated are closer to fresh juices based on quality factors. It can be concluded that PEF has the potential to become a suitable replacement to conventional process if improvements in design are applied. PMID:22347599
Impact of PEF and thermal processing on apple juice shelf life.
Torkamani, Ae
2011-09-01
Pulsed electric field (PEF) is a novel emerging technology which is believed to have the potential to substitute conventional thermal pasteurization (HTST). In the current study PEF was compared with HTST based on microbial inactivation and quality attributes. Juice was prepared by extracting it from Semirum apples. They were chilled to 4°C over night. Then were divided into two lots, one was treated by PEF and the other by HTST. The treated juices were cultured on tryphtic soy broth (TSB) and results were recorded for 168 days. Quality changes were characterized by color and sensory test. Color changes were quantified using Hunter Lab equipment and equation. Sensory changes were evaluated by test panelists. Using selective media E. Coli was enumerated, the total count of the organism was noticeably lower than PEF treated specimen and after 168. The count didn't reach the initial population. Whereas in PEF treated juice bacterial count bounced back to the initial count and exceeds. Results from Hunter Lab indicated a of 3.04 and 3.08 system for PEF and HTST treated juices. Sensory panel showed that PEF is superior to thermal treatment. The study indicated HTST is more suitable based on food safety encounters. However PEF treated are closer to fresh juices based on quality factors. It can be concluded that PEF has the potential to become a suitable replacement to conventional process if improvements in design are applied.
Effects of nanosecond pulsed electrical fields (nsPEFs) on the cell cycle of CHO and Jurkat cells
NASA Astrophysics Data System (ADS)
Mahlke, Megan A.; Navara, Christopher; Ibey, Bennett L.
2014-03-01
Exposure to nano-second pulsed electrical fields (nsPEFs) can cause poration of external and internal cell membranes, DNA damage, and disassociation of cytoskeletal components, all of which are capable of disrupting a cell's ability to replicate. Variations between cell lines in membrane and cytoskeletal structure as well as in survival of nsPEF exposure should correspond to unique line-dependent cell cycle effects. Additionally, phase of cell cycle during exposure may be linked to differential sensitivities to nsPEFs across cell lines, as DNA structure, membrane elasticity, and cytoskeletal structure change dramatically during the cell cycle. Populations of Jurkat and Chinese Hamster Ovary (CHO) cells were examined post-exposure (10 ns pulse trains at 150kV/cm) by analysis of DNA content via propidium iodide staining and flow cytometric analysis at various time points (1, 6, and 12h post-exposure) to determine population distribution in cell cycle phases. Additionally, CHO and Jurkat cells were synchronized in G1/S and G2/M phases, pulsed, and analyzed to evaluate role of cell cycle phase in survival of nsPEFs. CHO populations recovered similarly to sham populations postnsPEF exposure and did not exhibit a phase-specific change in response. Jurkat cells exhibited considerable apoptosis/necrosis in response to nsPEF exposure and were unable to recover and proliferate in a manner similar to sham exposed cells. Additionally, Jurkat cells appear to be more sensitive to nsPEFs in G2/M phases than in G1/S phases. Recovery of CHO populations suggests that nsPEFs do not inhibit proliferation in CHO cells; however, inhibition of Jurkat cells post-nsPEF exposure coupled with preferential cell death in G2/M phases suggest that cell cycle phase during exposure may be an important factor in determining nsPEF toxicity in certain cell lines. Interestingly, CHO cells have a more robust and rigid cytoskeleton than Jurkat cells which is thought to contribute to their ability to survive nsPEFs. The ability of the CHO cytoskeleton to recover and complete mitosis after nsPEF-induced damage in G2/M phase may be integral to the cell line's higher tolerance of nsPEF exposure.
Proceedings: pellet fuels conference
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1995-12-31
The conference brought together professionals from the process- engineered-fuels (PEF), utility, paper, plastics, and boiler industries. Although the last two decades have produced technical breakthroughs, efforts to advance PEF must now focus on increasing commercial breakthroughs. Successful commercialization will depend on increasing supplier, consumer, and regulator confidence and support by demonstrating the performance and value of PEF products. Speakers provided updates on how PEF technology is evolving with respect to technical, economic, and regulatory challenges. Actions critical toward full commercialization of PEF were then considered. Discussion groups addressed materials sourcing, fuel processing and transportation, combustion, and ash handling.
Moreira, Francisca C; Soler, J; Fonseca, Amélia; Saraiva, Isabel; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P
2015-09-15
The current study has proved the technical feasibility of including electrochemical advanced oxidation processes (EAOPs) in a multistage strategy for the remediation of a sanitary landfill leachate that embraced: (i) first biological treatment to remove the biodegradable organic fraction, oxidize ammonium and reduce alkalinity, (ii) coagulation of the bio-treated leachate to precipitate humic acids and particles, followed by separation of the clarified effluent, and (iii) oxidation of the resulting effluent by an EAOP to degrade the recalcitrant organic matter and increase its biodegradability so that a second biological process for removal of biodegradable organics and nitrogen content could be applied. The influence of current density on an UVA photoelectro-Fenton (PEF) process was firstly assessed. The oxidation ability of various EAOPs such as electro-Fenton (EF) with two distinct initial total dissolved iron concentrations ([TDI]0), PEF and solar PEF (SPEF) was further evaluated and these processes were compared with their analogous chemical ones. A detailed assessment of the two first treatment stages was made and the biodegradability enhancement during the SPEF process was determined by a Zahn-Wellens test to define the ideal organics oxidation state to stop the EAOP and apply the second biological treatment. The best current density was 200 mA cm(-2) for a PEF process using a BDD anode, [TDI]0 of 60 mg L(-1), pH 2.8 and 20 °C. The relative oxidation ability of EAOPs increased in the order EF with 12 mg [TDI]0 L(-1) < EF with 60 mg [TDI]0 L(-1) < PEF with 60 mg [TDI]0 L(-1) ≤ SPEF with 60 mg [TDI]0 L(-1), using the abovementioned conditions. While EF process was much superior to the Fenton one, the superiority of PEF over photo-Fenton was less evident and SPEF attained similar degradation to solar photo-Fenton. To provide a final dissolved organic carbon (DOC) of 163 mg L(-1) to fulfill the discharge limits into the environment after a second biological process, 6.2 kJ L(-1) UV energy and 36 kWh m(-3) electrical energy were consumed using SPEF with a BDD anode at 200 mA cm(-2), 60 mg [TDI]0 L(-1), pH 2.8 and 20 °C. Copyright © 2015 Elsevier Ltd. All rights reserved.
Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thompson, Gary L., E-mail: gary.l.thompson.3@gmail.com; Roth, Caleb C.; Kuipers, Marjorie A.
2016-01-29
Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known tomore » be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.« less
Histopathology of normal skin and melanomas after nanosecond pulsed electric field treatment.
Chen, Xinhua; James Swanson, R; Kolb, Juergen F; Nuccitelli, Richard; Schoenbach, Karl H
2009-12-01
Nanosecond pulsed electric fields (nsPEFs) can affect the intracellular structures of cells in vitro. This study shows the direct effects of nsPEFs on tumor growth, tumor volume, and histological characteristics of normal skin and B16-F10 melanoma in SKH-1 mice. A melanoma model was set up by injecting B16-F10 into female SKH-1 mice. After a 100-pulse treatment with an nsPEF (40-kV/cm field strength; 300-ns duration; 30-ns rise time; 2-Hz repetition rate), tumor growth and histology were studied using transillumination, light microscopy with hematoxylin and eosin stain and transmission electron microscopy. Melanin and iron within the melanoma tumor were also detected with specific stains. After nsPEF treatment, tumor development was inhibited with decreased volumes post-nsPEF treatment compared with control tumors (P<0.05). The nsPEF-treated tumor volume was reduced significantly compared with the control group (P<0.01). Hematoxylin and eosin stain and transmission electron microscopy showed morphological changes and nuclear shrinkage in the tumor. Fontana-Masson stain indicates that nsPEF can externalize the melanin. Iron stain suggested nsPEF caused slight hemorrhage in the treated tissue. Histology confirmed that repeated applications of nsPEF disrupted the vascular network. nsPEF treatment can significantly disrupt the vasculature, reduce subcutaneous murine melanoma development, and produce tumor cell contraction and nuclear shrinkage while concurrently, but not permanently, damaging peripheral healthy skin tissue in the treated area, which we attribute to the highly localized electric fields surrounding the needle electrodes.
NASA Astrophysics Data System (ADS)
Dai, Jie; Wu, Shan; Kong, Yan; Chi, Zhihong; Si, Lu; Sheng, Xinan; Cui, Chuanliang; Fang, Jing; Zhang, Jue; Guo, Jun
2017-01-01
The PI3K/mTOR/AKT pathway is activated in most melanomas, but mTOR inhibitors used singly have limited activity against advanced melanomas. The application of nanosecond pulsed electric fields (nsPEFs) is a promising cancer therapy approach. In this study, we evaluated the synergistic anti-tumour efficacy of the mTOR inhibitor everolimus in conjunction with nsPEFs against melanoma. The combined treatment of nsPEFs and everolimus gradually decreased cell growth concurrent with nsPEF intensity. nsPEFs alone or combined with everolimus could promote melanoma cell apoptosis, accompanied with a loss in cellular mitochondrial membrane potential and an increase in Ca2+ levels. In vivo experiments showed that a combination of the mTOR inhibitor everolimus and nsPEFs improved the inhibitory effect, and all skin lesions caused by nsPEFs healed in 1 week without any observed adverse effect. Combination treatment induced caspase-dependent apoptosis through the upregulation of the pro-apoptotic factor Bax and downregulation of the anti-apoptotic factor Bcl-2. Everolimus and nsPEFs synergistically inhibited angiogenesis by decreasing the expression of vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR), and CD34. Our findings indicate that nsPEFs in combination with an mTOR inhibitor can be used as a potential treatment approach for advanced melanoma.
Somolinos, M; García, D; Condón, S; Mañas, P; Pagán, R
2008-07-01
The aim was to evaluate the biosynthetic requirements for the repair of sublethal membrane damages in Saccharomyces cerevisiae cells after exposure to pulsed electric fields (PEF). The partial loss of the integrity and functionality of the cytoplasmic membrane was assessed by adding sodium chloride to the recovery medium. More than 2 log(10) cycles of survivors were sublethally injured after PEF. Repair of sublethal membrane damages occurred when survivors to PEF were incubated in Sabouraud Broth for 4 h at room temperature. The addition of inhibitors, such as chloramphenicol, rifampicin, 5-fluorocytosine, nalidixic acid, cycloheximide, cerulenin, miconazol and sodium azide to the liquid repair medium showed that the repair of PEF-injured cells required energy and protein synthesis. The extent of the sublethal damages was greater in PEF-treated cells at pH 4.0 than at pH 7.0. This work confirms that membrane damage is an important event in the PEF-inactivation of yeast. The mechanism of yeast inactivation by PEF seems to differ from that of bacteria, as the repair of sublethal damages requires protein synthesis. Knowledge about the damages inflicted by PEF leads to a better description of the mechanism of yeast inactivation.
Induction of apoptosis of liver cancer cells by nanosecond pulsed electric fields (nsPEFs).
He, Ling; Xiao, Deyou; Feng, Jianguo; Yao, Chenguo; Tang, Liling
2017-02-01
The application of nanosecond pulsed electric fields (nsPEFs) is a novel method to induce the death of cancer cells. NsPEFs could directly function on the cell membrane and activate the apoptosis pathways, then induce apoptosis in various cell lines. However, the nsPEFs-inducing-apoptosis action sites and the exact pathways are not clear now. In this study, nsPEFs were applied to the human liver cancer cells HepG2 with different parameters. By apoptosis assay, morphological observation, detecting the mitochondrial membrane potential (ΔΨ m ), intracellular calcium ion concentration ([Ca 2+ ]i) and the expressions of key apoptosis factors, we demonstrated that nsPEFs could induce the morphology of cell apoptosis, the change in ΔΨ m , [Ca 2+ ]i and the upregulation of some key apoptosis factors, which revealed the responses of liver cancer cells and indicated that cells may undergo apoptosis through the mitochondria-dependent pathway after nsPEFs were applied.
In vitro antioxidant activity of pet ether extract of black pepper
Singh, Ramnik; Singh, Narinder; Saini, B.S.; Rao, Harwinder Singh
2008-01-01
Objective: To investigate the in vitro antioxidant activity of different fractions (R1, R2 and R3) obtained from pet ether extract of black pepper fruits (Piper nigrum Linn.) Materials and Methods: The fractions R1, R2 and R3 were eluted from pet ether and ethyl acetate in the ratio of 6:4, 5:5 and 4:6, respectively. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. Results: The free radical scavenging activity of the different fractions of pet ether extract of P. nigrum (PEPN) increased in a concentration dependent manner. The R3 and R2 fraction of PEPN in 500 µg/ml inhibited the peroxidation of a linoleic acid emulsion by 60.48±3.33% and 58.89±2.51%, respectively. In DPPH free radical scavenging assay, the activity of R3 and R2 were found to be almost similar. The R3 (100µg/ml) fraction of PEPN inhibited 55.68±4.48% nitric oxide radicals generated from sodium nitroprusside, whereas curcumin in the same concentration inhibited 84.27±4.12%. Moreover, PEPN scavenged the superoxide radical generated by the Xanthine/Xanthine oxidase system. The fraction R2 and R3 in the doses of 1000µg/ml inhibited 61.04±5.11% and 63.56±4.17%, respectively. The hydroxyl radical was generated by Fenton's reaction. The amounts of total phenolic compounds were determined and 56.98 µg pyrocatechol phenol equivalents were detected in one mg of R3. Conclusions: P. nigrum could be considered as a potential source of natural antioxidant. PMID:20040947
Kebebe, Dereje; Mulisa, Eshetu; Gashe, Fanta
2017-01-01
Background Currently, antimalarial drug resistance poses a serious challenge. This stresses the need for newer antimalarial compounds. Carica papaya is used traditionally and showed in vitro antimalarial activity. This study attempted to evaluate in vivo antimalarial activity of C. papaya in mice. Methods In vivo antimalarial activity of solvent fractions of the plant was carried out against early P. berghei infection in mice. Parasitemia, temperature, PCV, and body weight of mice were recorded. Windows SPSS version 16 (one-way ANOVA followed by Tukey's post hoc test) was used for data analysis. Results The pet ether and chloroform fractions of C. papaya fruit rind and root produced a significant (p < 0.001) chemosuppressive effect. A maximum parasite suppression of 61.78% was produced by pet ether fraction of C. papaya fruit rind in the highest dose (400 mg/kg/day). Only 400 mg/kg/day dose of chloroform fraction of C. papaya root exhibited a parasite suppression effect (48.11%). But, methanol fraction of the plant parts produced less chemosuppressive effect. Conclusion Pet ether fraction of C. papaya fruit rind had the highest antimalarial activity and could be a potential source of lead compound. Further study should be done to show the chemical and metabolomic profile of active ingredients. PMID:29391947
Smith, Caroline Mary; Jones, Abigail; Dass, Dipankar; Murthi, Govind; Lindley, Richard
2015-02-01
The use of fibrin sealant in the management of pilonidal sinus disease has not previously been described in children. We present our experience of primary pit excision and use of fibrin sealant (PEF) and compare outcomes with lateralising flap procedures (LFP). A single centre retrospective case note review of all children who had undergone a definitive procedure for pilonidal sinus from August 2006 to Dec 2013 was performed using data expressed as median (range) and compared using Fisher's exact test. P<0.05 was regarded as significant. Forty-one children were identified having undergone 49 procedures, with median age 15 (12-16 years) and follow up 32 (8-92) months. Groups were comparable for disease severity. Ten children underwent primary PEF and twenty-six LFP. Two children had recurrence following primary PEF and had repeat PEF which was curative. Overall recurrence rates following PEF procedure were comparable to LFP (17% vs 21%; P=1.0). There were no wound dehiscences in the PEF group and one wound infection. There was one wound dehiscence and one wound infection in the LFP group. Median operative time for PEF was lower than LFP (20 vs 60 min, P=0.001). 83% of PEF procedures were performed as day cases. One child was lost to follow up, and two children progressed to adult services. We recommend PEF in children with pilonidal sinus disease as primary treatment and for recurrence. PEF has comparable recurrence and wound infection rates to LFPs, is performed as day case, has shorter anaesthetic times, and the risk of wound dehiscence is avoided. Copyright © 2015 Elsevier Inc. All rights reserved.
Najim, N; Aryana, Kayanush J
2013-06-01
Pulsed electric field (PEF) processing involves the application of pulses of voltage for less than 1 s to fluid products placed between 2 electrodes. The effect of mild PEF on beneficial characteristics of probiotic bacteria Lactobacillus acidophilus and Lactobacillus delbrueckii ssp. bulgaricus is not clearly understood. The objective of this study was to determine the influence of mild PEF conditions on acid tolerance, growth, and protease activity of Lb. acidophilus LA-K and Lactobacillus delbrueckii ssp. bulgaricus LB-12. A pilot plant PEF system (OSU-4M; The Ohio State University, Columbus) was used. The PEF treatments were positive square unipolar pulse width of 3 µs, pulse period of 0.5s, electric field strength of 1 kV/cm, delay time of 20 µs, flow rate of 60 mL/min, and 40.5°C PEF treatment temperature. Both Lb. acidophilus LA-K and Lb. bulgaricus LB-12 subjected to mild PEF conditions were acid tolerant until the end of the 120 min of incubation, unlike the Lb. bulgaricus control, which was not acid tolerant after 30 min. The mild PEF-treated Lb. acidophilus LA-K and Lb. bulgaricus LB-12 reached the logarithmic phase of growth an hour earlier than the control. Mild PEF conditions studied significantly improved acid tolerance, exponential growth, and protease activity of both Lb. acidophilus LA-K and Lb. bulgaricus LB-12 compared with the control. The mild PEF conditions studied can be recommended for pretreating cultures to enhance these desirable attributes. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Anees, W; Blainey, D; Moore, V C; Robertson, K; Burge, P S
2011-05-01
Serial peak expiratory flow (PEF) records have been recommended as a first-line investigation in workers suspected as having occupational asthma (OA). To determine which PEF variability index best differentiates workers with OA from non-occupational asthmatics and unaffected irritant-exposed workers. PEF was measured at least four times daily for at least 3 weeks in three groups of subjects: (i) forty healthy grain-exposed farmers and dockers, (ii) forty-two consecutive workers with independently confirmed OA and (iii) forty-eight non-occupational asthmatics. Indices of PEF variability were compared between groups. The difference in mean PEF between rest and work periods best separated the occupational asthmatic workers from the others. The upper 95% confidence limit of this index for grain-exposed workers was 2.8% of predicted PEF (16 l/min) and 3.3% (15 l/min) for non-occupational asthmatics. Sensitivity for diagnosing OA using this index was 70%. An increase in diurnal variation on workdays of >7% had a sensitivity of only 27% for the diagnosis of OA. The difference between maximum PEF on workdays and minimum PEF on rest days had a sensitivity of <10% against non-occupational asthmatic controls. Difference in mean PEF between workdays and rest days is the best simple index for differentiating subjects with OA from those with non-OA or irritant-exposed healthy subjects. Differences >16 l/min are unlikely to be due to significant irritant exposure in healthy workers.
de Dios Alvarado, J; Villacís, F E; Zamora, G F
1983-06-01
A study was carried out wherein during the period August 1979 to January 1980, samples of raw and fermented cacao were analyzed monthly. These included two varieties: Arriba, taken from a farm in "Quevedo", and the EET-19, grown in "Pichilingüe" by the Instituto Nacional de Investigaciones Agropecuarias (INIAP). Taking the ear of cacao as a basis, the weight of its main parts was determined. The proximal composition was established in the cotyledons, with significant statistical differences in regard to moisture, protein, and ether extract content according to the month of harvest. As to the fermentation process, differences in moisture, ether extract and ash content were detected; differences in the ether extract and ash content were found between the two varieties. The fat extracted from the cotyledons presented different iodine, saponification and acidity index values between the raw and fermented samples, but none were determined between the varieties; as far as the month of harvest is concerned, differences in the acidity index were observed. The percentage composition of the main fatty acids is reported (palmitic, stearic, oleic, and linoleic acids). In order to suggest possible industrial ways of utilizing the cacao shell by-product which is discarded by the shelling machine, the chemical characteristics of five fractions were determined based on the functioning of the shelling machine. The moisture, protein, ether extract, ash, crude fiber, theobromine, and caffeine contents varied among the fractions, and it was dependent on the broken "nibs" content. Differences in the protein, ether extract, and ash content, according to the months of production, were found. Obviously, the high fat content in fractions A (fine dust) and B (fine ground), which varied from 30 to 11 g/100 g, merits its extraction; the remainder meal has a valuable protein and alkaloid content. The chemical characteristics of the fat extracted from the shell of two fractions were similar to the fat extracted from the cotyledons.
Hossain, Mohammed Munawar; Kabir, Mohammad Shah Hafez; Dinar, Md Abu Monsur; Arman, Md Saiful Islam; Rahman, Md Mominur; Hosen, S M Zahid; Dash, Raju; Uddin, Mir Muhammad Nasir
2017-09-26
The objective of the study was to evaluate the antidiarrheal and antinociceptive activities of ethanol extract and its chloroform and pet ether fraction of Phrynium imbricatum (Roxb.) leaves in mice. In the present study, the dried leaves of P. imbricatum were subjected to extraction with ethanol, and then it was fractioned by chloroform and pet ether solvent. Antidiarrheal effects were tested by using castor oil-induced diarrhea, castor oil-induced enteropooling, and gastrointestinal transit test. Antinociceptive activity was evaluated by using the acetic acid-induced writhing test and formalin-induced paw licking test. The standard drug loperamide (5 mg/kg) showed significant (p<0.001) inhibitory activity against castor oil-induced diarrhea, in which all the examined treatments decreased the frequency of defecation and were found to possess an anti-castor oil-induced enteropooling effect in mice by reducing both weight and volume of intestinal content significantly, and reducing the propulsive movement in castor oil-induced gastrointestinal transit using charcoal meal in mice. The results showed that the ethanol extract of P. imbricatum leaves has significant dose-dependent antinociceptive activity, and among its two different fractions, the pet ether fraction significantly inhibited the abdominal writhing induced by acetic acid and the licking times in formalin test at both phases. These findings suggest that the plant may be a potential source for the development of a new antinociceptive drug and slightly suitable for diarrhea, as it exhibited lower activity. Our observations resemble previously published data on P. imbricatum leaves.
Effect of pulsed electric field on the rheological and colour properties of soy milk.
Xiang, Bob Y; Simpson, Marian V; Ngadi, Michael O; Simpson, Benjamin K
2011-12-01
The effects of pulsed electric field (PEF) treatments on rheological and colour properties of soy milk were evaluated. Flow behaviour, viscosity and rheological parameters of PEF-treated soy milk were monitored using a controlled stress rheometer. For PEF treatments, electric field intensity of 18, 20 and 22 kV cm(-1) and number of pulses of 25, 50, 75 and 100 were used. For the measurements of rheological properties of soy milk shear rates between 0 and 200 s(-1) was used. The rheological behaviour of control and the PEF-treated soy milk were described using a power law model. The PEF treatments affected the rheological properties of soy milk. Apparent viscosity of soy milk increased from 6.62 to 7.46 (10(-3) Pa s) with increase in electric field intensity from 18 to 22 kV cm(-1) and increase in the number of pulses from 0 to 100. The consistency index (K) of soy milk also changed with PEF treatments. Lightness (L*), red/greenness (a*) and yellowness/blueness (b*) of soy milk were affected by PEF treatments.
PEF and UV combined system for pathogen microorganisms inactivation in liquid food products
NASA Astrophysics Data System (ADS)
Cramariuc, R.; Popa, M.; Tudorache, A.; Brînduşe, E.; Kontek, A.; Mitelut, A.; Fotescu, L.; Cramariuc, B.; Geicu, M.; Nisiparu, L.
2011-06-01
Pulsed electrical field (PEF) treatment is a non-thermal food preservation technology based on the use of the electrical field in impulses applied in order to inactivate and control pathogen microorganisms in foods. This technology is highly appreciated for its ability to prolong the shelf life of the treated product without the use of heat and also for its ability to preserve the product's sensory qualities and nutritional value as well as for the microbiological control of the treated products. This paper presents the PEF and UV treatment methods, or a combination between the two, for microbe inactivation in liquid products. The experiments were carried out using yeasts, lactic bacteria and acetic bacteria in the following systems: stand-alone treatments (PEF or UV) or in combination (UV+PEF or PEF+UV). The results of these experiments showed that one can obtain total inactivation of microorganisms using the combined UV+PEF system, thus leading to the possibility of increasing liquid food products quality as compared to the quality obtained using thermal pasteurization.
Product environmental footprint in policy and market decisions: Applicability and impact assessment.
Lehmann, Annekatrin; Bach, Vanessa; Finkbeiner, Matthias
2015-07-01
In April 2013, the European Commission published the Product and Organisation Environmental Footprint (PEF/OEF) methodology--a life cycle-based multicriteria measure of the environmental performance of products, services, and organizations. With its approach of "comparability over flexibility," the PEF/OEF methodology aims at harmonizing existing methods, while decreasing the flexibility provided by the International Organization for Standardization (ISO) standards regarding methodological choices. Currently, a 3-y pilot phase is running, aiming at testing the methodology and developing product category and organization sector rules (PEFCR/OEFSR). Although a harmonized method is in theory a good idea, the PEF/OEF methodology presents challenges, including a risk of confusion and limitations in applicability to practice. The paper discusses the main differences between the PEF and ISO methodologies and highlights challenges regarding PEF applicability, with a focus on impact assessment. Some methodological aspects of the PEF and PEFCR Guides are found to contradict the ISO 14044 (2006) and ISO 14025 (2006). Others, such as prohibition of inventory cutoffs, are impractical. The evaluation of the impact assessment methods proposed in the PEF/OEF Guide showed that the predefined methods for water consumption, land use, and abiotic resources are not adequate because of modeling artefacts, missing inventory data, or incomplete characterization factors. However, the methods for global warming and ozone depletion perform very well. The results of this study are relevant for the PEF (and OEF) pilot phase, which aims at testing the PEF (OEF) methodology (and potentially adapting it) as well as addressing challenges and coping with them. © 2015 SETAC.
Pulsed electric fields for pasteurization: defining processing conditions
USDA-ARS?s Scientific Manuscript database
Application of pulsed electric fields (PEF) technology in food pasteurization has been extensively studied. Optimal PEF treatment conditions for maximum microbial inactivation depend on multiple factors including PEF processing conditions, production parameters and product properties. In order for...
NASA Astrophysics Data System (ADS)
Guo, Jinsong; Ma, Ruonan; Su, Bo; Li, Yinglong; Zhang, Jue; Fang, Jing
2016-05-01
Avermectins, a group of anthelmintic and insecticidal agents produced from Streptomyces avermitilis, are widely used in agricultural, veterinary, and medical fields. This study presents the first report on the potential of using nanosecond pulsed electric fields (nsPEFs) to improve avermectin production in S. avermitilis. The results of colony forming units showed that 20 pulses of nsPEFs at 10 kV/cm and 20 kV/cm had a significant effect on proliferation, while 100 pulses of nsPEFs at 30 kV/cm exhibited an obvious effect on inhibition of agents. Ultraviolet spectrophotometry assay revealed that 20 pulses of nsPEFs at 15 kV/cm increased avermectin production by 42% and reduced the time for reaching a plateau in fermentation process from 7 days to 5 days. In addition, the decreased oxidation reduction potential (ORP) and increased temperature of nsPEFs-treated liquid were evidenced to be closely associated with the improved cell growth and fermentation efficiency of avermectins in S. avermitilis. More importantly, the real-time RT-PCR analysis showed that nsPEFs could remarkably enhance the expression of aveR and malE in S. avermitilis during fermentation, which are positive regulator for avermectin biosynthesis. Therefore, the nsPEFs technology presents an alternative strategy to be developed to increase avermectin output in fermentation industry.
Saldaña, Guillermo; Cebrián, Guillermo; Abenoza, María; Sánchez-Gimeno, Cristina; Álvarez, Ignacio; Raso, Javier
2017-02-01
The influence of the electric field intensity and pulse width on the improvement of total polyphenol index (TPI) and colour intensity (CI) during extraction in an ethanolic solution (30%) and during fermentation-maceration has been investigated in different grape varieties: Grenache from two harvesting times, Syrah and Tempranillo. The aim of this study was to develop a procedure to establish the PEF treatment conditions that cause enough permeabilization in the skin cells of different grape varieties to obtain a significant improvement in the vinification process in terms of increment on the polyphenol content or reduction of maceration time. Results obtained in this investigation indicate that extraction of polyphenols in a solution of ethanol (30%) for 2 h could be a suitable procedure to know if the PEF technology is effective for improving extraction of polyphenols from the grapes during vinification and to determine the most suitable PEF treatment conditions to obtain this objective. Improvement in the extraction during vinification only was observed with those grapes and under treatment conditions in which the improvement of the polyphenol extraction was higher than 40%. Other interesting observation from this research is the highest efficacy of PEF when treatments of the same duration are applied using longer pulses. Therefore, in a continuous process, where the flow processed is determined by the frequency applied by the PEF generator, it is possible to increase the processing capacity of the PEF installation. Benefits from PEF treatment of the grapes before the maceration step in the vinification process have been demonstrated. Nevertheless, the characteristics of the grapes may change in different vintages and grape varieties. Therefore, it is of high importance to be able to determine the optimum PEF conditions in order to obtain the desired benefit during the vinification. The rapid method developed permits to determine PEF process parameters before the application of the PEF treatment with the objective of facilitating the phenolic extraction and therefore, reducing the maceration time. In these cases, it would be possible to remove the skins from the rest of the wine earlier, and therefore, increase the processing capacity of the winery.
Kasture, V S; Chopde, C T; Deshmukh, V K
2000-07-01
The ethanolic extracts of leaves of Albizzia lebbeck and flowers of Hibiscus rosa sinesis and the petroleum ether extract of flowers of Butea monosperma exhibited anticonvulsant activity. The bioassay guided fractionation indicated that the anticonvulsant activity lies in the methanolic fraction of chloroform soluble part of ethanolic extract of the leaves of A. lebbeck, acetone soluble part of ethanolic extract of H. rosa sinesis flowers and acetone soluble part of petroleum ether extract of B. monosperma flowers. The fractions protected animals from maximum electro shock, electrical kindling and pentylenetetrazole-induced convulsions in mice. The fractions also inhibited convulsions induced by lithium-pilocarpine and electrical kindling. However, they failed to protect animals from strychnine-induced convulsions. The fractions antagonised the behavioral effects of D-amphetamine and potentiated the pentobarbitone-induced sleep. The fractions raised brain contents of gamma-aminobutyric acid (GABA) and serotonin. These fractions were found to be anxiogenic and general depressant of central nervous system.
[Column chromatography purification and analysis of biodiesel by transesterification].
Liu, Yang; Yi, Huai-feng; Chen, Yu; Wu, Yu-long; Yang, Ming-de; Chen, Zeng; Tong, Jun-mao
2012-02-01
In the present paper, crude biodiesel prepared with sorbifolia oil as raw material by transesterification was purified by column chromatography, then the composition of biodiesel was analyzed by gas chromatography, FTIR, GC-MS and 1H NMR. Column chromatography can separate the crude biodiesel into two fractions: petroleum ether eluted fraction (A1) and methanol eluted fraction (A2). Petroleum ether eluted fraction was mainly biodiesel fraction, which was produced from sorbifolia oil by transesterification, including methyl linoleate, methyl cis-9-octadecenoate and so on; methanol eluted fraction was mainly glycerol fraction, which came from the side reaction of transesterification. The results show that the purity of refined biodiesel increased from 77.51% to 93.872, and the product recovery rate reached up to 91.04% after the purification by column chromatography. The results obtained by FTIR and 1H NMR further showed that the column chromatography can effectively improve the purity of biodiesel. This paper provides a basis for industrialization of purification of biodiesel.
Behavior of yeast cells in aqueous suspension affected by pulsed electric field.
El Zakhem, H; Lanoisellé, J-L; Lebovka, N I; Nonus, M; Vorobiev, E
2006-08-15
This work discusses pulsed electric fields (PEF) induced effects in treatment of aqueous suspensions of concentrated yeast cells (S. cerevisiae). The PEF treatment was done using pulses of near-rectangular shape, electric field strength was within E=2-5 kV/cm and the total time of treatment was t(PEF)=10(-4)-0.1 s. The concentration of aqueous yeast suspensions was in the interval of C(Y)=0-22 (wt%), where 1% concentration corresponds to the cellular density of 2x10(8) cells/mL. Triton X-100 was used for studying non-ionic surfactant additive effects. The electric current peak value I was measured during each pulse application, and from these data the electrical conductivity sigma was estimated. The PEF-induced damage results in increase of sigma with t(PEF) increasing and attains its saturation level sigma approximately sigma(max) at long time of PEF treatment. The value of sigma(max) reflects the efficiency of damage. The reduced efficiency of damage at suspension volume concentration higher than phi(Y) approximately 32 vol% is explained by the percolation phenomenon in the randomly packed suspension of near-spherical cells. The higher cytoplasmic ions leakage was observed in presence of surfactant. Experiments were carried out in the static and continuous flow treatment chambers in order to reveal the effects of mixing in PEF-treatment efficiency. A noticeable aggregation of the yeast cells was observed in the static flow chamber during the PEF treatment, while aggregation was not so pronounced in the continuous flow chamber. The nature of the enhanced aggregation under the PEF treatment was revealed by the zeta-potential measurements: these data demonstrate different zeta-potential signs for alive and dead cells. The effect of the electric field strength on the PEF-induced extraction of the intracellular components of S. cerevisiae is discussed.
2013-01-01
Background Caesalpinia bonducella is an important medicinal plant for its traditional uses against different types of diseases. Therefore, the present study investigated the antimicrobial, antidiarrhoeal, and cytotoxic activities of the methanol extract and ethyl acetate, chloroform, and petroleum ether (pet. ether) fractions of C. bonducella leaves. Methods The antibacterial potentialities of methanol extract and its fractions of C. bonducella leaves were investigated by the disc diffusion method against four gram-positive and five gram-negative bacteria at 300, 500 and 800 μg/disc. Kanamycin (30 μg/disc) was used as the standard drug. Antidiarrhoeal activities of leaf extracts were evaluated at two doses (200 and 400 mg/kg) and compared with loperamide in a castor oil-induced diarrhoeal model in rat. The fractions were subjected to a brine shrimp lethality test to evaluate their cytotoxicity. Results The methanol extract and other three fractions exhibited better activities at higher concentrations. Amongst, the chloroform fraction showed maximum activity at all three concentrations (300, 500, and 800 μg/disc) against almost all bacteria. S. aureus and P. aeruginosa showed better sensitivities to all extracts at all three concentrations excluding the pet. ether fraction. Bacillus megaterium and Klebsiella spp. were two bacteria amongst nine that showed lowest sensitivity to the extracts. Maximum zone of inhibition (25-mm) was obtained by the methanol extract at an 800 μg/disc concentration against S. aureus. In the antidiarrhoeal test, all fractions exhibited dose-dependent actions, which were statistically significant (p < 0.05). Ethyl acetate fraction exerted maximum inhibition (51.11%) against defecation, whereas 57.75% inhibition was obtained for loperamide. Moderate cytotoxicity was found for the methanol extract and its three fractions compared with the standard drug vincristine sulfate in the brine shrimp bioassay. In the present study, the LC50 values of the methanol crude extract and ethyl acetate, chloroform, pet. ether fractions and vincristine sulfate were 223.87, 281.84, 112.2, 199.53, and 12.59 μg/mL, respectively. Therefore, the ethyl acetate fraction showed maximum cytotoxicity, whereas minimum cytotoxicity was observed for the chloroform fraction. Conclusion The present study revealed that the ethyl acetate fraction of the C. bonducella leaves has significant antidiarrhoeal properties. The methanol extract and other three fractions of the C. bonducella leaves possess potent antibacterial activities along with moderate cytotoxicities that may lead to new drug development. PMID:23663985
Billah, Muhammad Mutassim; Islam, Rafikul; Khatun, Hajera; Parvin, Shahnaj; Islam, Ekramul; Islam, Sm Anisul; Mia, Akbar Ali
2013-05-12
Caesalpinia bonducella is an important medicinal plant for its traditional uses against different types of diseases. Therefore, the present study investigated the antimicrobial, antidiarrhoeal, and cytotoxic activities of the methanol extract and ethyl acetate, chloroform, and petroleum ether (pet. ether) fractions of C. bonducella leaves. The antibacterial potentialities of methanol extract and its fractions of C. bonducella leaves were investigated by the disc diffusion method against four gram-positive and five gram-negative bacteria at 300, 500 and 800 μg/disc. Kanamycin (30 μg/disc) was used as the standard drug. Antidiarrhoeal activities of leaf extracts were evaluated at two doses (200 and 400 mg/kg) and compared with loperamide in a castor oil-induced diarrhoeal model in rat. The fractions were subjected to a brine shrimp lethality test to evaluate their cytotoxicity. The methanol extract and other three fractions exhibited better activities at higher concentrations. Amongst, the chloroform fraction showed maximum activity at all three concentrations (300, 500, and 800 μg/disc) against almost all bacteria. S. aureus and P. aeruginosa showed better sensitivities to all extracts at all three concentrations excluding the pet. ether fraction. Bacillus megaterium and Klebsiella spp. were two bacteria amongst nine that showed lowest sensitivity to the extracts. Maximum zone of inhibition (25-mm) was obtained by the methanol extract at an 800 μg/disc concentration against S. aureus. In the antidiarrhoeal test, all fractions exhibited dose-dependent actions, which were statistically significant (p < 0.05). Ethyl acetate fraction exerted maximum inhibition (51.11%) against defecation, whereas 57.75% inhibition was obtained for loperamide. Moderate cytotoxicity was found for the methanol extract and its three fractions compared with the standard drug vincristine sulfate in the brine shrimp bioassay. In the present study, the LC50 values of the methanol crude extract and ethyl acetate, chloroform, pet. ether fractions and vincristine sulfate were 223.87, 281.84, 112.2, 199.53, and 12.59 μg/mL, respectively. Therefore, the ethyl acetate fraction showed maximum cytotoxicity, whereas minimum cytotoxicity was observed for the chloroform fraction. The present study revealed that the ethyl acetate fraction of the C. bonducella leaves has significant antidiarrhoeal properties. The methanol extract and other three fractions of the C. bonducella leaves possess potent antibacterial activities along with moderate cytotoxicities that may lead to new drug development.
Cheng, Sheung-Tak; Leung, Edward M F; Chan, Trista Wai Sze
2014-06-01
This study examined the associations between social network types and peak expiratory flow (PEF), and whether these associations were mediated by social and physical activities and mood. Nine hundred twenty-four community-dwelling Chinese older adults, who were classified into five network types (diverse, friend-focused, family-focused, distant family, and restricted), provided data on demographics, social and physical activities, mood, smoking, chronic diseases, and instrumental activities of daily living. PEF and biological covariates, including blood lipids and glucose, blood pressure, and height and weight, were assessed. Two measures of PEF were analyzed: the raw reading in L/min and the reading expressed as percentage of predicted normal value on the basis of age, sex, and height. Diverse, friend-focused, and distant family networks were hypothesized to have better PEF values compared with restricted networks, through higher physical and/or social activities. No relative advantage was predicted for family-focused networks because such networks tend to be associated with lower physical activity. Older adults with diverse, friend-focused, and distant family networks had significantly better PEF measures than those with restricted networks. The associations between diverse network and PEF measures were partially mediated by physical exercise and socializing activity. The associations between friend-focused network and PEF measures were partially mediated by socializing activity. No significant PEF differences between family-focused and restricted networks were found. Findings suggest that social network types are associated with PEF in older adults, and that network-type differences in physical and socializing activity is partly responsible for this relationship. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Frelinger, A L; Torres, A S; Caiafa, A; Morton, C A; Berny-Lang, M A; Gerrits, A J; Carmichael, S L; Neculaes, V B; Michelson, A D
2016-01-01
Therapeutic use of activated platelet-rich plasma (PRP) has been explored for wound healing, hemostasis and antimicrobial wound applications. Pulse electric field (PEF) stimulation may provide more consistent platelet activation and avoid complications associated with the addition of bovine thrombin, the current state of the art ex vivo activator of therapeutic PRP. The aim of this study was to compare the ability of PEF, bovine thrombin and thrombin receptor activating peptide (TRAP) to activate human PRP, release growth factors and induce cell proliferation in vitro. Human PRP was prepared in the Harvest SmartPreP2 System and treated with vehicle, PEF, bovine thrombin, TRAP or Triton X-100. Platelet activation and procoagulant markers and microparticle generation were measured by flow cytometry. Released growth factors were measured by ELISA. The releasates were tested for their ability to stimulate proliferation of human epithelial cells in culture. PEF produced more platelet-derived microparticles, P-selectin-positive particles and procoagulant annexin V-positive particles than bovine thrombin or TRAP. These differences were associated with higher levels of released epidermal growth factor after PEF than after bovine thrombin or TRAP but similar levels of platelet-derived, vascular-endothelial, and basic fibroblast growth factors, and platelet factor 4. Supernatant from PEF-treated platelets significantly increased cell proliferation compared to plasma. In conclusion, PEF treatment of fresh PRP results in generation of microparticles, exposure of prothrombotic platelet surfaces, differential release of growth factors compared to bovine thrombin and TRAP and significant cell proliferation. These results, together with PEF's inherent advantages, suggest that PEF may be a superior alternative to bovine thrombin activation of PRP for therapeutic applications.
Jarald, E. E.; Joshi, S. B.; Jain, D. C.; Edwin, S.
2013-01-01
Various extracts of flowers of Cassia fistula Linn (Leguminosae) such as petroleum ether (60-80°), chloroform, acetone, ethanol, aqueous, and crude aqueous extracts and two fractions of ethanol extract were tested for antihyperglycemic activity in glucose-overloaded hyperglycemic rats. The effective antihyperglycemic extracts and fraction were tested for their hypoglycemic activity at two dose levels, 200 and 400 mg/kg, respectively. To confirm their utility in higher models, the effective extracts and fraction of C. fistula were subjected to antidiabetic study in an alloxan-induced diabetic model at two dose levels, 200 and 400 mg/kg, respectively. Biochemical parameters like glucose, urea, creatinine, serum cholesterol, serum triglyceride, high-density lipoprotein, low-density lipoprotein, hemoglobin, and glycosylated hemoglobin were also assessed in experimental animals. The petroleum ether and ethanol extracts of C. fistula and the water-soluble fraction of ethanol extract were found to exhibit significant antihyperglycemic activity. The extracts, at the given doses, did not produce hypoglycemia in fasted normal rats, and the fraction exhibited weak hypoglycemic effect after 2 h of the treatment. Treatment of diabetic rats with ethanol extract and water-soluble fraction of this plant restored the elevated biochemical parameters significantly (P<0.05) to the normal level. No activity was found in the petroleum ether extract of the plant. Comparatively, the water-soluble fraction of ethanol extract was found to be more effective than the ethanol extract, and the activity was comparable with that of the standard, glibenclamide (5 mg/kg). PMID:24302797
Nanosecond pulsed electric fields and the cell cycle
NASA Astrophysics Data System (ADS)
Mahlke, Megan A.
Exposure to nanosecond pulsed electrical fields (nsPEFs) can cause poration of external and internal cell membranes, DNA damage, and disassociation of cytoskeletal components, all of which are capable of disrupting a cell's ability to replicate. The phase of the cell cycle at the time of exposure is linked to differential sensitivities to nsPEFs across cell lines, as DNA structure, membrane elasticity, and cytoskeletal structure change dramatically during the cell cycle. Additionally, nsPEFs are capable of activating cell cycle checkpoints, which could lead to apoptosis or slow population growth. NsPEFs are emerging as a method for treating tumors via apoptotic induction; therefore, investigating the relevance of nsPEFs and the cell cycle could translate into improved efficacy in tumor treatment. Populations of Jurkat and Chinese Hamster Ovary (CHO) cells were examined post-exposure (10 ns pulse trains at 150kV/cm) by analysis of DNA content via propidium iodide staining and flow cytometric analysis at various time points (1, 6, and 12h post-exposure) to determine population distribution in cell cycle phases. Additionally, CHO and Jurkat cells were synchronized in G1/S and G2/M phases, pulsed, and analyzed to evaluate the role of cell cycle phase in survival of nsPEFs. CHO populations appeared similar to sham populations post-nsPEFs but exhibited arrest in the G1 phase at 6h after exposure. Jurkat cells exhibited increased cell death after nsPEFs compared to CHO cells but did not exhibit checkpoint arrest at any observed time point. The G1/S phase checkpoint is partially controlled by the action of p53; the lack of an active p53 response in Jurkat cells could contribute to their ability to pass this checkpoint and resist cell cycle arrest. Both cell lines exhibited increased sensitivity to nsPEFs in G2/M phase. Live imaging of CHO cells after nsPEF exposure supports the theory of G1/S phase arrest, as a reduced number of cells undergo mitosis within 24 h when compared to sham treated cells. CHO cells undergoing mitosis after exposure also exhibit improper separation of chromatids which could indicate loss of function of the mitotic spindle checkpoint. Activation and loss of function of checkpoints in CHO but not Jurkat cells after nsPEF exposure suggests that activation of cell cycle checkpoints could be important in defining the character of cell line specific recovery after nsPEF exposure. Moreover, the increased sensitivity in G2/M phase exhibited by both cell lines indicates that cell cycle phase is an important consideration during nsPEF exposure, particularly when aiming to induce apoptosis.
Sun, Ying-Ying; Liu, Xiao-Xiao; Wang, Chang-Hai
2010-06-01
To study the effects of extracts of Enteromorpha prolifera on the growth of the four species of red tide microalgae (Amphidinium hoefleri, Karenia mikimitoi, Alexandrium tamarense and Skeletonema costatum), the extracts were extracted with five solvents (methanol, acetone, ethyl acetate, chloroform and petroleum ether), respectively. Based on the observation of algal morphology and the measurement of algal density, cell size and the contents of physiological indicators (chlorophyll, protein and polysaccharide), the results showed methanol extracts of E. prolifera had the strongest action. The inhibitory effects of A. hoefleri, K. mikimitoi, A. tamarense and S. costatum by the methanol extracts were 54.0%, 48.1%, 44.0% and 37.5% in day 10, respectively. The extracts of E. prolifera extracted with methanol, acetone and ethyl acetate caused cavities, pieces and pigment reduction in cells, and those with chloroform and petroleum ether caused goffers on cells. The extracts of E. prolifera extracted with all the five solvents decreased athletic ability of the cells, among which those extracted with ethyl acetate, chloroform and petroleum ether decreased cell size of test microalgae. The further investigation found that the methanol extracts significantly decreased contents of chlorophyll, protein and polysaccharide in the cells of those microalgae. The inhibitory effect of chlorophyll, protein and polysaccharide contents of four species of microalgae by the methanol extracts was about 51%. On the basis of the above experiments, dry powder of E. prolifera were extracts with methanol, and extracts were obtained. The methanol extracts were partitioned to petroleum ether phase, ethyl acetate phase, n-butanol phase and distilled water phase by liquid-liquid fractionation, and those with petroleum ether and ethyl acetate significantly inhibited the growth of all test microalgae, and the inhibitory effect of four species of microalgae by those two extracts was above 25% in day 10. Our researches expressed that antialgal substances in E. prolifera extracted with methanol were obtained. And two fractions (petroleum ether phase and ethyl acetate phase) that inhibited the growth of all test microalgae were obtained when the methanol extracts was fractionated by liquid-liquid fractionation.
Development of array piezoelectric fingers towards in vivo breast tumor detection
NASA Astrophysics Data System (ADS)
Xu, Xin; Chung, Youngsoo; Brooks, Ari D.; Shih, Wei-Heng; Shih, Wan Y.
2016-12-01
We have investigated the development of a handheld 4 × 1 piezoelectric finger (PEF) array breast tumor detector system towards in vivo patient testing, particularly, on how the duration of the DC applied voltage, the depression depth of the handheld unit, and breast density affect the PEF detection sensitivity on 40 patients. The tests were blinded and carried out in four phases: with DC voltage durations 5, 3, 2, to 0.8 s corresponding to scanning a quadrant, a half, a whole breast, and both breasts within 30 min, respectively. The results showed that PEF detection sensitivity was unaffected by shortening the applied voltage duration from 5 to 0.8 s nor was it affected by increasing the depression depth from 2 to 6 mm. Over the 40 patients, PEF detected 46 of the 48 lesions (46/48)—with the smallest lesion detected being 5 mm in size. Of 28 patients (some have more than one lesion) with mammography records, PEF detected 31/33 of all lesions (94%) and 14/15 of malignant lesions (93%), while mammography detected 30/33 of all lesions (91%) and 12/15 of malignant lesions (80%), indicating that PEF could detect malignant lesions not detectable by mammography without significantly increasing false positives. PEF's detection sensitivity is also shown to be independent of breast density, suggesting that PEF could be a potential tool for detecting breast cancer in young women and women with dense breasts.
Guionet, Alexis; David, Fabienne; Zaepffel, Clément; Coustets, Mathilde; Helmi, Karim; Cheype, Cyril; Packan, Denis; Garnier, Jean-Pierre; Blanckaert, Vincent; Teissié, Justin
2015-06-01
One of the different ways to eradicate microorganisms, and particularly bacteria that might have an impact on health consists in the delivery of pulsed electric fields (PEFs). The technologies of millisecond (ms) or microsecond (μs) PEF are still well known and used for instance in the process of fruit juice sterilization. However, this concept is costly in terms of delivered energy which might be too expensive for some other industrial processes. Nanosecond pulsed electric fields (nsPEFs) might be an alternative at least for lower energetic cost. However, only few insights were available and stipulate a gain in cost and in efficiency as well. Using Escherichia coli, the impact of frequency and low rate on eradication and energy consumption by msPEF, μsPEF and nsPEF have been studied and compared. While a 1 log10 was reached with an energy cost of 100 and 158 kJ/L with micro- and millisecond PEFs respectively, nsPEF reached the reduction for similar energy consumption. The best condition was obtained for a 1 log10 deactivation in 0.5h, for energy consumption of 143 kJ/L corresponding to 0.04 W · h when the field was around 100 kV/cm. Improvement can also be expected by producing a generator capable to increase the electric field. Copyright © 2014 Elsevier B.V. All rights reserved.
Papageorgiou, George Z; Tsanaktsis, Vasilios; Bikiaris, Dimitrios N
2014-05-07
Poly(ethylene-2,5-furandicarboxylate) (PEF) is a new alipharomatic polyester that can be prepared from monomers derived from renewable resources like furfural and hydroxymethylfurfural. For this reason it has gained high interest recently. In the present work it was synthesized from the dimethylester of 2,5-furandicarboxylic acid and ethylene glycol by applying the two-stage melt polycondensation method. The thermal behavior of PEF was studied in comparison to its terephthalate and naphthalate homologues poly(ethylene terephthalate) (PET) and poly(ethylene naphthalate) (PEN), which were also synthesized following the same procedure. The equilibrium melting point of PEF was found to be 265 °C while the heat of fusion for the pure crystalline PEF was estimated to be about 137 J g(-1). The crystallization kinetics was analyzed using various models. PET showed faster crystallization rates than PEN and this in turn showed faster crystallization than PEF, under both isothermal and non-isothermal conditions. The spherulitic morphology of PEF during isothermal crystallization was investigated by polarized light microscopy (PLM). A large nucleation density and a small spherulite size were observed for PEF even at low supercoolings, in contrast to PET or PEN. Thermogravimetric analysis indicated that PEF is thermally stable up to 325 °C and the temperature for the maximum degradation rate was 438 °C. These values were a little lower than those for PET or PEN.
Schilling, Susanne; Schmid, Sandra; Jäger, Henry; Ludwig, Michael; Dietrich, Helmut; Toepfl, Stefan; Knorr, Dietrich; Neidhart, Sybille; Schieber, Andreas; Carle, Reinhold
2008-06-25
As an alternative to thermal pasteurization, pulsed electric fields (PEF) were applied to apple juices on laboratory and pilot plant scale, investigating the effects on juice quality. PEF application still falls under the EU Novel Food Regulation. Consequently, extensive investigation of quality parameters is a prerequisite to prove substantial equivalence of juices resulting from the novel process and conventional production, respectively. Juice composition was not affected by PEF treatment. However, browning of the juices provided evidence of residual enzyme activities. On laboratory scale, complete deactivation of peroxidase (POD) and polyphenoloxidase (PPO) was achieved when PEF treatment and preheating of the juices to 60 degrees C were combined. Under these conditions, a synergistic effect of heat and PEF was observed. On pilot plant scale, maximum PPO deactivation of 48% was achieved when the juices were preheated to 40 degrees C and PEF-treated at 30 kV/cm (100 kJ/kg). Thus, minimally processed juices resulted from PEF processing, when applied without additional conventional thermal preservation. Since this product type was characterized by residual native enzyme activities and nondetectable levels of 5-hydroxymethylfurfural, also when preheating up to 40 degrees C was included, it ranged between fresh and pasteurized juices regarding consumers' expectation of freshness and shelf life. Consistent with comparable iron contents among all juice samples, no electrode corrosion was observed under the PEF conditions applied.
Development of an accurate portable recording peak-flow meter for the diagnosis of asthma.
Hitchings, D J; Dickinson, S A; Miller, M R; Fairfax, A J
1993-05-01
This article describes the systematic design of an electronic recording peak expiratory flow (PEF) meter to provide accurate data for the diagnosis of occupational asthma. Traditional diagnosis of asthma relies on accurate data of PEF tests performed by the patients in their own homes and places of work. Unfortunately there are high error rates in data produced and recorded by the patient, most of these are transcription errors and some patients falsify their records. The PEF measurement itself is not effort independent, the data produced depending on the way in which the patient performs the test. Patients are taught how to perform the test giving maximal effort to the expiration being measured. If the measurement is performed incorrectly then errors will occur. Accurate data can be produced if an electronically recording PEF instrument is developed, thus freeing the patient from the task of recording the test data. It should also be capable of determining whether the PEF measurement has been correctly performed. A requirement specification for a recording PEF meter was produced. A commercially available electronic PEF meter was modified to provide the functions required for accurate serial recording of the measurements produced by the patients. This is now being used in three hospitals in the West Midlands for investigations into the diagnosis of occupational asthma. In investigating current methods of measuring PEF and other pulmonary quantities a greater understanding was obtained of the limitations of current methods of measurement, and quantities being measured.(ABSTRACT TRUNCATED AT 250 WORDS)
Improving Electrode Durability of PEF Chamber by selecting suitable material
USDA-ARS?s Scientific Manuscript database
Corrosion resistance of four materials - titanium, platinized titanium, stainless steel, and boron carbide - as electrodes in a Pulsed Electric Field (PEF) system was studied to reduce electrode material migration into the food by electrode corrosion. The PEF process conditions were 28 kV/cm field s...
Characterization of nanosecond pulse electrical field shock waves using imaging techniques
NASA Astrophysics Data System (ADS)
Mimun, L. Chris; Ibey, Bennett L.; Roth, Caleb C.; Barnes, Ronald A.; Sardar, Dhiraj K.; Beier, Hope T.
2015-03-01
Nanosecond pulsed electric fields (nsPEF) cause the formation of small pores, termed nanopores, in the membrane of cells. Current nanoporation models treat nsPEF exposure as a purely electromagnetic phenomenon, but recent publications showing pressure transients, ROS production, temperature gradients, and pH waves suggest the stimulus may be physically and chemically multifactorial causing elicitation of diverse biological conditions and stressors. Our research group's goal is to quantify the breadth and participation of these stressors generated during nsPEF exposure and determine their relative importance to the observed cellular response. In this paper, we used advanced imaging techniques to identify a possible source of nsPEF-induced acoustic shock waves. nsPEFs were delivered in an aqueous media via a pair of 125 μm tungsten electrodes separated by 100 μm, mirroring our previously published cellular exposure experiments. To visualize any pressure transients emanating from the electrodes or surrounding medium, we used the Schlieren imaging technique. Resulting images and measurements confirmed that mechanical pressure waves and electrode-based stresses are formed during nsPEF, resulting in a clearer understanding of the whole exposure dosimetry. This information will be used to better quantify the impact of nsPEF-induced acoustic shock waves on cells, and has provided further evidence of non-electrical-field induced exposures for elicitation of bioieffects.
Zhang, Sha; Yang, Ruijin; Zhao, Wei; Hua, Xiao; Zhang, Wenbin; Zhang, Zhong
2011-01-01
Effects of pulsed electric field (PEF) treatments on the volatile profiles of milk were studied and compared with pasteurized treatment of high temperature short time (HTST) (75 °C, 15 s). Volatile compounds were extracted by solid-phase micro-extraction (SPME) and identified by gas chromatography/mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). A total of 37 volatile compounds were determined by GC-MS, and 19 volatile compounds were considered to be major contributors to the characteristic flavor of milk samples. PEF treatment resulted in an increase in aldehydes. Milk treated with PEF at 30 kV/cm showed the highest content of pentanal, hexanal, and nonanal, while heptanal and decanal contents were lower than in pasteurized milk, but higher than in raw milk. All the methyl ketones detected in PEF milk were lower than in pasteurized milk. No significant differences in acids (acetic acid, butanoic acid, hexanoic acid, octanoic acid, and decanoic acid), lactones, and alcohols were observed between pasteurized and PEF-treated samples; however, 2(5H)-furanone was only detected in PEF-treated milk. Although GC-MS results showed that there were some volatile differences between pasteurized and PEF-treated milk, GC-O data showed no significant difference between the 2 samples.
Hua, Yuan-Yuan; Wang, Xiao-Shu; Zhang, Yu; Yao, Chen-Guo; Zhang, Xi-Ming; Xiong, Zheng-Ai
2012-04-01
The application of pulsed electric fields (PEF) is emerging as a new technique for tumor therapy. Picosecond pulsed electric fields (psPEF) can be transferred to target deep tissue non-invasively and precisely, but the research of the biological effects of psPEF on cells is limited. Electric theory predicts that intense psPEF will target mitochondria and lead to changes in transmembrane potential, therefore, it is hypothesized that it can induce mitochondrial-mediated apoptosis. HeLa cells were exposed to psPEF in this study to investigate this hypothesis. MTT assay demonstrated that intense psPEF significantly inhibited the proliferation of HeLa cells in a dose-dependent manner. Typical characteristics of apoptosis in HeLa cells were observed, using transmission electron microscopy. Loss of mitochondrial transmembrane potential was explored using laser scanning confocal microscopy with Rhodamine-123 (Rh123) staining. Furthermore, the mitochondrial apoptotic events were also confirmed by western blot analysis for the release of cytochrome C and apoptosis-inducing factor from mitochondria into the cytosol. In addition, activation of caspase-3, caspase-9, upregulation of Bax, p53 and downregulation of Bcl-2 were observed in HeLa cells also indicating apoptosis. Taken together, these results demonstrate that intense psPEF induce cell apoptosis through a mitochondrial-mediated pathway.
Agcam, E; Akyıldız, A; Evrendilek, G Akdemir
2014-12-15
The inactivation kinetics of pectin methyl esterase (PME) during the shelf life (4°C-180 days) of freshly squeezed orange juice samples processed by both pulsed electric fields (PEF) and heat pasteurization (HP) was evaluated in the study. The PME inactivation level after the PEF (25.26 kV/cm-1206.2 μs) and HP (90°C-20s) treatments were 93.8% and 95.2%, respectively. The PME activity of PEF-processed samples decreased or did not change, while that of HP samples increased during storage (p<0.01). A kinetic model was developed expressing PME inactivation as a function of the PEF treatment conditions, and this enabled the estimation of the reaction rate constant (587.8-2375.4s(-1)), and the time required for a 90% reduction (De, 3917.7-969.5s). Quantification of the increase in PEF energy to ensure a ten-fold reduction in De (ze, 63.7 J), activation electric fields (-921.2 kV cm(-1)mol(-1)), and electrical activation energy (12.9 kJ mol(-1)) was also carried out. Consequently, PEF processing was very effective for the inactivation of PME and for providing stability of orange juice during storage. Copyright © 2014. Published by Elsevier Ltd.
Practice-based learning: the role of practice education facilitators in supporting mentors.
Carlisle, Caroline; Calman, Lynn; Ibbotson, Tracy
2009-10-01
Central to the provision of high quality clinical placements for nursing and midwifery students are mentors who help engender a positive learning environment. In 2004 the Scottish Executive Health Department (now Scottish Government Health Directorates), NHS Scotland, NHS Education for Scotland, NHS Boards and Higher Education Institutions initiated and supported the establishment of the Practice Education Facilitator (PEF) role whose purpose is to ensure that the student experience, at both pre- and post-registration level, is of the highest quality, primarily through the support of mentors. A 3-year project evaluated the implementation and impact of the PEF role across Scotland. The study utilised both quantitative and qualitative data collection, with a sample comprising mentors, PEFs, students and other key stakeholders. This paper reports on selected findings from that study, specifically the perceived impact of the PEF in supporting mentors. Findings indicate that the PEF role has been accepted widely across Scotland and is seen as valuable to the development of quality clinical learning environments. PEFs provide support and guidance for mentors when dealing with 'failing' students, and encourage the identification of innovative learning opportunities. PEFs play an active part in student evaluation of their placements, but further work is needed in order that the feedback to clinical areas and mentors is timely.
Wong, Chun Kwan; Hung, Patricia; Lee, Kellie L H; Kam, Kai Man
2009-02-01
Florisil solid-phase extraction (SPE) cartridges were used for purifying ciguatoxin (CTX)-contaminated coral fish extracts, with the aim of removing extracted lipid but retaining optimal level of CTXs in the purified fractions. The CTX-containing fraction (target fraction) in fish ether extract was isolated and purified by eluting through a commercially available Florisil cartridge with hexane-acetone-methanol solvent mixtures of increasing polarity (hexane-acetone (4:1, v/v) < acetone-methanol (7:3, v/v) < 100% methanol). Application of Florisil SPE using acetone-methanol (7:3, v/v) condition facilitated the separation of 4.2 +/- 0.4 mg (mean +/- standard error of the mean (SEM)) of purified target fraction from 20 mg ether extract with good retention of CTXs. The mouse bioassay was used to demonstrate that the average CTX recovery of the target fraction from CTX-spiked samples was 75.8% +/- 3.3%, which was significantly increased by 96.7% +/- 15% when compared with CTX recovery from ether extracts (44.8% +/- 5.2%) without performing SPE purification. Over 70% of non-target lipids were removed in which no CTX toxicity was found. Moreover, the target fractions of both CTX-spiked and naturally CTX-contaminated samples gave more prominent toxic responses of hypothermia and/or induced more rapid death of the mice. The use of acetone-methanol (7:3, v/v) condition in the elution could significantly improve overall recovery of CTXs, while minimizing the possible interferences of lipid matrix from co-extractants on mice.
Bin Karim, Mohammed Faisal; Imam, Hasan; Sarker, Md Moklesur-Rahman; Uddin, Nizam; Hasan, Nahid; Paul, Nirmala; Haque, Tahmina
2015-05-01
In this phyto-pharmacological screening of Pistia stratiotes L leaf and root extracts each separately in two different solvents demonstrated its potential medicinal value. Apparent antioxidant value is demonstrated by DPPH, Nitric oxide scavenging and Ferric ion reducing method. Additionally, total flavonoid and phenolic compounds were measured. The leaf methanolic extract scavenged both nitric oxide (NO) and DPPH radical with a dose dependent manner. But the pet ether fraction of root was found to have highest efficacy in Fe(3±) reducing power assay. Flavonoid was found to contain highest in the pet ether fraction of root (411.35mg/g) in terms of quercetin equivalent, similarly highest amount (34.96mg/g) of total phenolic compounds (assayed as gallic acid equivalents) were found to contain in the same fraction. The methanolic fractions appeared less cytotoxic compared to pet ether extracts. The plant extracts caused a dose dependent decrease in faecal droppings in both castor oil and magnesium sulphate induced diarrhea, where as leaf extracts in each solvent appeared most effective. Also, the plant extracts showed anthelmintic activity in earthworm by inducing paralysis and death in a dose dependent manner. At highest doses (50 mg/ml) all fractions were almost effective as the positive control piperazine citrate (10 mg/ml). Thus, besides this cytotoxic effect it's traditional claim for therapeutic use can never be overlooked.
Influence of Pulsed Electric Fields and Mitochondria-Cytoskeleton Interactions on Cell Respiration.
Goswami, Ishan; Perry, Justin B; Allen, Mitchell E; Brown, David A; von Spakovsky, Michael R; Verbridge, Scott S
2018-06-19
Pulsed electric fields with microsecond pulse width (μsPEFs) are used clinically; namely, irreversible electroporation/Nanoknife is used for soft tissue tumor ablation. The μsPEF pulse parameters used in irreversible electroporation (0.5-1 kV/cm, 80-100 pulses, ∼100 μs each, 1 Hz frequency) may cause an internal field to develop within the cell because of the disruption of the outer cell membrane and subsequent penetration of the electric field. An internal field may disrupt voltage-sensitive mitochondria, although the research literature has been relatively unclear regarding whether such disruptions occur with μsPEFs. This investigation reports the influence of clinically used μsPEF parameters on mitochondrial respiration in live cells. Using a high-throughput Agilent Seahorse machine, it was observed that μsPEF exposure comprising 80 pulses with amplitudes of 600 or 700 V/cm did not alter mitochondrial respiration in 4T1 cells measured after overnight postexposure recovery. To record alterations in mitochondrial function immediately after μsPEF exposure, high-resolution respirometry was used to measure the electron transport chain state via responses to glutamate-malate and ADP and mitochondrial membrane potential via response to carbonyl cyanide-p-trifluoromethoxyphenylhydrazone. In addition to measuring immediate mitochondrial responses to μsPEF exposure, measurements were also made on cells permeabilized using digitonin and those with compromised cytoskeleton due to actin depolymerization via treatment with the drug latrunculin B. The former treatment was used as a control to tease out the effects of plasma membrane permeabilization, whereas the latter was used to investigate indirect effects on the mitochondria that may occur if μsPEFs impact the cytoskeleton on which the mitochondria are anchored. Based on the results, it was concluded that within the pulse parameters tested, μsPEFs alone do not hinder mitochondrial physiology but can be used to impact the mitochondria upon compromising the actin. Mitochondrial susceptibility to μsPEF after actin depolymerization provides, to our knowledge, a novel avenue for cancer therapeutics. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Effect of altitude on spirometric parameters and the performance of peak flow meters.
Pollard, A. J.; Mason, N. P.; Barry, P. W.; Pollard, R. C.; Collier, D. J.; Fraser, R. S.; Miller, M. R.; Milledge, J. S.
1996-01-01
BACKGROUND: Portable peak flow meters are used in clinical practice for measurement of peak expiratory flow (PEF) at many different altitudes throughout the world. Some PEF meters are affected by gas density. This study was undertaken to establish which type of meter is best for use above sea level and to determine changes in spirometric measurements at altitude. METHODS: The variable orifice mini-Wright peak flow meter was compared with the fixed orifice Micro Medical Microplus turbine microspirometer at sea level and at Everest Base Camp (5300 m). Fifty one members of the 1994 British Mount Everest Medical Expedition were studied (age range, 19-55). RESULTS: Mean forced vital capacity (FVC) fell by 5% and PEF rose by 25.5%. However, PEF recorded with the mini-Wright peak flow meter underestimated PEF by 31%, giving readings 6.6% below sea level values. FVC was lowest in the mornings and did not improve significantly with acclimatisation. Lower PEF values were observed on morning readings and were associated with higher acute mountain sickness scores, although the latter may reflect decreased effort in those with acute mountain sickness. There was no change in forced expiratory volume in one second (FEV1) at altitude when measured with the turbine microspirometer. CONCLUSIONS: The cause of the fall in FVC at 5300 m is unknown but may be attributed to changes in lung blood volume, interstitial lung oedema, or early airways closure. Variable orifice peak flow meters grossly underestimate PEF at altitude and fixed orifice devices are therefore preferable where accurate PEF measurements are required above sea level. PMID:8711651
DOE Office of Scientific and Technical Information (OSTI.GOV)
Partha, Sarathy K.; Ravulapalli, Ravikiran; Allingham, John S.
2014-08-21
Calpains are Ca 2+dependent intracellular cysteine proteases that cleave a wide range of protein substrates to help implement Ca 2+ signaling in the cell. The major isoforms of this enzyme family, calpain-1 and calpain-2, are heterodimers of a large and a small subunit, with the main dimer interface being formed through their C-terminal penta-EF hand (PEF) domains. Calpain-3, or p94, is a skeletal muscle-specific isoform that is genetically linked to limb-girdle muscular dystrophy. Biophysical and modeling studies with the PEF domain of calpain-3 support the suggestion that full-length calpain-3 exists as a homodimer. Here, we report the crystallization of calpain-3'smore » PEF domain and its crystal structure in the presence of Ca 2+, which provides evidence for the homodimer architecture of calpain-3 and supports the molecular model that places a protease core at either end of the elongated dimer. Unlike other calpain PEF domain structures, the calpain-3 PEF domain contains a Ca 2+ bound at the EF5-hand used for homodimer association. Three of the four Ca 2+-binding EF-hands of the PEF domains are concentrated near the protease core, and have the potential to radically change the local charge within the dimer during Ca 2+ signaling. Examination of the homodimer interface shows that there would be steric clashes if the calpain-3 large subunit were to try to pair with a calpain small subunit.« less
USDA-ARS?s Scientific Manuscript database
Bioassay-guided fractionation of the marine sponge Lendenfeldia dendyi and the soft coral Sinularia dura resulted in the isolation of five polybrominated diphenyl ethers (1-5). The structures of the isolated compounds were determined using spectroscopic methods(lD and 2D NMR) and HRMS analyses. The ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kalika, D.S.; Krishnaswamy, R.K.
1993-12-31
The relaxation behavior of poly (ether ether ketone) [PEEK] has been investigated using dielectric relaxation spectroscopy; the glass-rubber ({alpha}) relaxation and a sub-glass ({beta}) relaxation were examined for the amorphous material and both cold-crystallized and melt-crystallized specimens. Analysis of the data using the Cole-Cole modification of the Debye equation allowed determination of the dielectric relaxation strength and relaxation broadening parameter for both transitions as a function of material crystallization history. The crystallized specimens displayed a positive offset in isochronal loss temperature for both the {alpha} and {beta} relaxations, with the {alpha} relaxation broadened significantly. The measured dipolar response was interpretedmore » using a three-phase morphological model encompassing a crystalline phase, a mobile amorphous phase, and a rigid amorphous phase. Determination of phase fractions based on dipolar mobilization across the glass-rubber relaxation revealed a finite rigid amorphous phase fraction for both the cold-crystallized specimens which was relatively insensitive to thermal history and degree of crystallinity (W{sub RAP}40.20).« less
Pasteurization of strawberry puree using a pilot plant pulsed electric fields (PEF) system
USDA-ARS?s Scientific Manuscript database
The processing of strawberry puree by pulsed electric fields (PEF) in a pilot plant system has never been evaluated. In addition, a method does not exist to validate the exact number and shape of the pulses applied during PEF processing. Both buffered peptone water (BPW) and fresh strawberry puree (...
Pankiewicz, Urszula; Sujka, Monika; Kowalski, Radosław; Mazurek, Artur; Włodarczyk-Stasiak, Marzena; Jamroz, Jerzy
2017-04-15
The cultures of Saccharomyces cerevisiae were treated with pulsed electric fields (PEF) in order to obtain a maximum accumulation of selenium and zinc ions (simultaneously) in the biomass. The following concentrations: 100μgSe/ml and 150μgZn/ml medium were assumed to be optimal for the maximum accumulation of these ions, that is 43.07mg/gd.m. for selenium and 14.48mg/gd.m. for zinc, in the cultures treated with PEF. At optimal PEF parameters: electric field strength of 3kV/cm and pulse width of 10μs after the treatment of 20-h culture for 10min, the maximum accumulation of both ions in the yeast cells was observed. Application of PEF caused the increase of ions accumulation by 65% for selenium and 100% for zinc. Optimization of PEF parameters led to the further rise in the both ions accumulation resulting in over 2-fold and 2.5-fold higher concentration of selenium and zinc. Copyright © 2016 Elsevier Ltd. All rights reserved.
González-Arenzana, Lucía; López-Alfaro, Isabel; Garde-Cerdán, Teresa; Portu, Javier; López, Rosa; Santamaría, Pilar
2018-03-23
This study was performed with the aim of reducing the microbial communities of wines after alcoholic fermentation to improve the establishment of commercial Oenococcus oeni inoculum for developing the malolactic fermentation. Microbial community reduction was accomplished by applying Pulsed Electric Field (PEF) technology to four different wines. Overall, significant reductions in yeast population were observed. To a lesser extent, lactic acid bacteria were reduced while acetic acid bacteria were completely eliminated after the PEF treatment. In three out of the four tested wines, a decrease in the competitive pressure between microorganisms due to the detected reduction led to a general but slight shortening of the malolactic fermentation duration. In the wine with the most adverse conditions to commercial starter establishment, the shortest malolactic fermentation was reached after PEF treatment. Finally, the sensorial quality of three out of the four treated wines was considered better after the PEF treatment. Therefore, PEF technology meant an important tool for improving the malolactic fermentation performance. Copyright © 2018 Elsevier B.V. All rights reserved.
Arroyo, Cristina; Eslami, Sara; Brunton, Nigel P; Arimi, Joshua M; Noci, Francesco; Lyng, James G
2015-05-01
Pulsed electric fields (PEF) is a novel nonthermal technology that has the potential to cause physical disruption to muscle tissue which in turn could alter the sensorial aspects of meat in both a positive (e.g., enhanced tenderization) and a negative way (e.g., off-flavor development). If there is a risk of off-flavor development it should be identified prior to embarking on an extensive investigation on PEF in meat tenderization and turkey meat was chosen for this purpose as it is particularly prone to oxidation. The objective of this study was to investigate the effect of various PEF treatments on the quality attributes of turkey breast meat. Turkey breast meat obtained 1 d postslaughter was treated in a batch PEF chamber with increasing electric field strength up to 3 kV/cm and analyzed for lipid oxidation by thiobarbituric acid reactive substances assay (TBARS) with up to 5 d storage at 4°C in aerobic conditions. In a separate experiment, turkey breast meat samples were exposed to PEF under various combinations of pulse number, frequency, and voltage. Following PEF treatments weight loss, cook loss, lipid oxidation, texture, and color were assessed by instrumental methods. A sensory analysis was also performed to determine consumer acceptability for color, texture, and odor of the samples. Lipid oxidation in all PEF-treated samples progressed at the same rate with storage as the untreated samples and was not found to be significantly different to the control. Under the conditions examined PEF treatments did not induce differences in instrumentally measured weight loss, cook loss, lipid oxidation, texture, and color (raw and cooked) either on fresh or frozen samples. However, the sensory evaluation suggested that panelists could detect slight differences between the PEF-treated samples and the controls in terms of texture and odor. © 2015 Poultry Science Association Inc.
Chen, Wen-Juan; Xiong, Zheng-Ai; Zhang, Min; Yao, Chen-Guo; Zhao, Zhong-Yong; Hua, Yuan-Yuan; Zhou, Wei
2013-03-01
The non-invasive treatment of tumors with preserved fertility holds great promise. The application of pulsed electric field (PEF) is a new biomedical engineering technique for tumor therapy. Picosecond pulsed electric fields (psPEF) can be transferred to target deep tissue non-invasively and precisely; however, research of the biological effects of psPEF on cells is limited. Electric theory predicts that when the pulse duration decreases to nanoseconds and picoseconds, it will mainly affect organelles and lead to intracellular electromanipulations. Previous studies have shown that psPEF targets the mitochondria and induces apoptosis through a mitochondrial-mediated pathway in HeLa cells. The endoplasmic reticulum is also involved in the intrinsic pathways of apoptosis. In the present study, HeLa cells were exposed to psPEF to investigate the underlying mechanisms of apoptosis. MTT assay demonstrated that psPEF displayed strong growth inhibitory effects on HeLa cells. Treatment with psPEF led to marked cell apoptosis and cell cycle arrest at the G2/M phase. In addition, psPEF affected the phosphorylation levels of endoplasmic reticulum sensors and upregulated the expression of glucose-regulated protein 78 (GRP78), glucose-regulated protein 94 (GRP94) and CCAAT enhancer-binding protein (C/EBP) homologous protein (CHOP). These changes were accompanied by the elevation of intracellular Ca2+ concentrations. Furthermore, the activation of caspase-12, -9 and -3, led to the release of cytochrome c, as well as the upregulation of Bax and the downregulation of Bcl-2, as observed in the HeLa cells. Taken together, these data suggest that psPEF is an efficient apoptosis-inducing agent for HeLa cells, which exerts its effects, at least partially, via the endoplasmic reticulum stress and caspase-dependent signaling pathways.
Khanday, M A; Mallick, B N
2015-11-12
Rapid eye movement sleep (REMS) is regulated by the interaction of the REM-ON and REM-OFF neurons located in the pedunculo-pontine-tegmentum (PPT) and the locus coeruleus (LC), respectively. Many other brain areas, particularly those controlling non-REMS (NREMS) and waking, modulate REMS by modulating these REMS-related neurons. Perifornical (PeF) orexin (Ox)-ergic neurons are reported to increase waking and reduce NREMS as well as REMS; dysfunction of the PeF neurons are related to REMS loss-associated disorders. Hence, we were interested in understanding the neural mechanism of PeF-induced REMS modulation. As a first step we have recently reported that PeF Ox-ergic neurons modulate REMS by influencing the LC neurons (site for REM-OFF neurons). Thereafter, in this in vivo study we have explored the role of PeF inputs on the PPT neurons (site for REM-ON neurons) for the regulation of REMS. Chronic male rats were surgically prepared with implanted bilateral cannulae in PeF and PPT and electrodes for recording sleep-waking patterns. After post-surgical recovery sleep-waking-REMS were recorded when bilateral PeF neurons were stimulated by glutamate and simultaneously bilateral PPT neurons were infused with either saline or orexin receptor1 (OX1R) antagonist. It was observed that PeF stimulation increased waking and decreased NREMS as well as REMS, which were prevented by OX1R antagonist into the PPT. We conclude that the PeF stimulation-induced reduction in REMS was likely to be due to inhibition of REM-ON neurons in the PPT. As waking and NREMS are inversely related, subject to confirmation, the reduction in NREMS could be due to increased waking or vice versa. Based on our findings from this and earlier studies we have proposed a model showing connections between PeF- and PPT-neurons for REMS regulation. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.
Cheng, Dandan; Zhang, Yingying; Gao, Demin; Zhang, Hongmeng
2014-09-11
Pyrrosia petiolosa is commonly used as a traditional Chinese medicine for treatment of acute pyelonephritis, chronic bronchitis and bronchial asthma. This study aims to evaluate the antibacterial activity of the ethanol extract and its derived fractions of Pyrrosia petiolosa obtained with solvents of different polarities and to perform the anti-inflammatory screening. The powdered aerial parts of Pyrrosia petiolosa were used to extract various fractions with ethanol, petroleum ether, ethyl acetate, N-butanol and aqueous. Qualitative phytochemical screening was performed on the ethanol extract, petroleum ether fraction, ethyl acetate fraction, N-butanol fraction and aqueous fraction. The agar diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were employed to evaluate antibacterial activity of the ethanol extract and fractions. The in vitro cytotoxicity of ethanol extract and fractions was determined using MTT assay. The anti-inflammatory activity was analyzed using the mouse ear swelling induced by xylene. The phytochemical screening revealed the presence of anthraquinones, flavonoids, terpenoids, steroids, saponins, phenols and reducing sugars in the extract and fractions. Antibacterial results showed that petroleum ether fraction and N-butanol fraction inhibited all the tested microorganisms with the maximum inhibition zone of 15.25±0.35 mm. Ethyl acetate fraction also exhibited good antibacterial activity except Pseudomonas aeruginosa ATCC 27853, while extract and aqueous fraction inhibited 8 out of 13 (61.5%) of the tested microorganisms. The MIC values of ethanol extract and fractions ranged from 1.25 to 10.00 mg/mL and most of the MBC values were equal or twice as high as the corresponding MIC values. The in vitro cytotoxicity showed the ethanol extract and fractions exhibited non-toxic or low toxic activity against lung cancer cell lines A549 and mouse spleen cells. In anti-inflammatory experiment, ethanol extract at 5.0 and 10.0 mg/kg exhibited significant anti-inflammatory activity against the mouse ear swelling induced by xylene and the maximum inhibition rate reached as high as 67%. Pyrrosia petiolosa could be a potential candidate for future development of a novel antibacterial and anti-inflammatory agent. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Phytochemical Characterization of an Adaptogenic Preparation from Rhodiola heterodonta
Grace, Mary H.; Yousef, Gad G.; Kurmukov, Anvar G.; Raskin, Ilya; Lila, Mary Ann
2013-01-01
The phytochemical constituents of a biologically active, standardized, 80% ethanol extract of Rhodiola heterodonta were characterized. The extract was fractionated over a Sephadex LH-20 column to afford two main fractions representing two classes of secondary metabolites: phenylethanoids and proanthocyanidins. This fractionation facilitated the identification and quantification of individual compounds in the fractions and sub-fractions using HPLC, and LC-MS. The major compounds in the phenylethanoid fraction were heterodontoside, tyrosol methyl ether, salidroside, viridoside, mongrhoside, tyrosol, and the cyanogenic glucoside rhodiocyanoside A. These seven compounds comprised 17.4% of the EtOH extract. Proanthocyanidins ranged from oligomers to polymers based on epigallocatechin and gallate units. The main identified oligomeric compounds in the proanthocyanidin fraction were epigallocatechin gallate, epigallocatechin-epigallocatechin-3-O-gallate and 3-O-galloylepigallocatechin-epigallocatechin-3-O-gallate, which constituted 1.75% of the ethanol extract. Tyrosol methyl ether, mongrhoside, and the two proanthocyanidin dimers were reported for the first time from this species in this study. Intraperitoneal injection of the 80% ethanol extract increased survival time of mice under hypoxia by 192%, as an indication of adaptogenic activity. PMID:19768982
Mass dependence of calcium isotope fractionations in crown-ether resin chromatography.
Fujii, Yasuhiko; Nomura, Masao; Kaneshiki, Tositaka; Sakuma, Yoichi; Suzuki, Tatsuya; Umehara, Saori; Kishimoto, Tadahumi
2010-06-01
Benzo 18-crown-6-ether resin was synthesised by the phenol condensation polymerisation process in porous silica beads, of which particle diameter was ca 60micro Calcium adsorption chromatography was performed with the synthesised resin packed in a glass column. The effluent was sampled in fractions, and the isotopic abundance ratios of (42)Ca, (43)Ca, (44)Ca, and (48)Ca against (40)Ca were measured by a thermo-ionisation mass spectrometer. The enrichment of heavier calcium isotopes was observed at the front boundary of calcium adsorption chromatogram. The mass dependence of mutual separation of calcium isotopes was analysed by using the three-isotope-plots method. The slopes of three-isotope-plots indicate the relative values of mutual separation coefficients for concerned isotopic pairs. The results have shown the normal mass dependence; isotope fractionation is proportional to the reduced mass difference, (M - M')/MM', where M and M' are masses of heavy and light isotope, respectively. The mass dependence clarifies that the isotope fractionations are originated from molecular vibration. The observed separation coefficient epsilon is 3.1x10(-3) for the pair of (40)Ca and (48)Ca. Productivity of enriched (48)Ca by crown-ether-resin was discussed as the function of the separation coefficient and the height equivalent to the theoretical plate.
Tian, Mei-ling; Fang, Ting; Du, Mu-ying; Zhang, Fu-sheng
2016-04-01
To explore an efficient, safe, and speedy application of pulsed electric field (PEF) technology for enzymatic modification, effects of PEF treatment on the enzymatic activity, property and kinetic parameters of α-amylase were investigated. Conformational transitions were also studied with the aid of circular dichroism (CD) and fluorescence spectra. The maximum enzymatic activity of α-amylase was obtained under 15 kV/cm electric field intensity and 100 mL/min flow velocity PEF treatment, in which the enzymatic activity increased by 22.13 ± 1.14% compared with control. The activation effect could last for 18 h at 4 °C. PEF treatment could widen the range of optimum temperature for α-amylase, however, it barely exerted any effect on the optimum pH. On the other hand, α-amylase treated by PEF showed an increase of Vmax, t1/2 and ΔG, whereas a decrease of Km and k were observed. Furthermore, it can be observed from fluorescence and CD spectra that PEF treatment had increased the number of amino acid residues, especially that of tryptophan, on α-amylase surface with enhanced α-helices by 34.76% and decreased random coil by 12.04% on α-amylase when compared with that of untreated. These changes in structure had positive effect on enhancing α-amylase activity and property.
Rodríguez-González, Oscar; Walkling-Ribeiro, Markus; Jayaram, Shesha; Griffiths, Mansel W
2011-08-01
Prior to processing milk and cream were standardised and homogenised. Skim milk was cross-flow microfiltered (CFMF) prior to treatment with pulsed electric fields (PEF) or high temperature short time (HTST) pasteurization. The effect of temperature of the skim milk and product composition on the efficacy of PEF treatment was determined. The electrical conductivity of the product was related to fat and solids content and increased 5% for every g/kg increase of solids and decreased by nearly 0·7% for every g/kg increase of fat. From the three microbial groups analyzed (mesophilic, coliform, and psychrotroph) in milks differences (P<0·05) in the inactivation of mesophilic microorganisms were observed between the counts following PEF treatment, while HTST pasteurization resulted in higher reductions in all different counts than those obtained after PEF. Increasing the skim milk temperature prior to PEF treatment to about 34°C showed equivalent reductions in microbial counts to skim milk treated at 6°C in half the time. The reductions achieved by a combination of CFMF and PEF treatments were comparable to those achieved when CFMF was combined with HTST pasteurization. A higher reduction in coliform counts was observed in homogenised products subjected to PEF than in products that were only standardised for fat content.
Miller, M R; Atkins, P R; Pedersen, O F
2003-05-01
Recent evidence suggests that the frequency response requirements for peak expiratory flow (PEF) meters are higher than was first thought and that the American Thoracic Society (ATS) waveforms to test PEF meters may not be adequate for the purpose. The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters was tested by delivering two differently shaped flow-time profiles from a computer controlled explosive decompression device fitted with a fast response solenoid valve. These profiles matched population 5th and 95th centiles for rise time from 10% to 90% of PEF and dwell time of flow above 90% PEF. Profiles were delivered five times with identical chamber pressure and solenoid aperture at PEF. Any difference in recorded PEF for the two profiles indicates a poor dynamic response. The absolute (% of mean) flow differences in l/min for the V, MW, and PT PEF meters were 25 (4.7), 20 (3.9), and 2 (0.3), respectively, at PEF approximately 500 l/min, and 25 (10.5), 20 (8.7) and 6 (3.0) at approximately 200 l/min. For TZ and MS meters at approximately 500 l/min the differences were 228 (36.1) and 257 (39.2), respectively, and at approximately 200 l/min they were 51 (23.9) and 1 (0.5). All the meters met ATS accuracy requirements when tested with their waveforms. An improved method for testing the dynamic response of flow meters detects marked overshoot (underdamping) of TZ and MS responses not identified by the 26 ATS waveforms. This error could cause patient misclassification when using such meters with asthma guidelines.
Three-Dimensional Printing with Biomass-Derived PEF for Carbon-Neutral Manufacturing.
Kucherov, Fedor A; Gordeev, Evgeny G; Kashin, Alexey S; Ananikov, Valentine P
2017-12-11
Biomass-derived poly(ethylene-2,5-furandicarboxylate) (PEF) has been used for fused deposition modeling (FDM) 3D printing. A complete cycle from cellulose to the printed object has been performed. The printed PEF objects created in the present study show higher chemical resistance than objects printed with commonly available materials (acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), glycol-modified poly(ethylene terephthalate) (PETG)). The studied PEF polymer has shown key advantages for 3D printing: optimal adhesion, thermoplasticity, lack of delamination and low heat shrinkage. The high thermal stability of PEF and relatively low temperature that is necessary for extrusion are optimal for recycling printed objects and minimizing waste. Several successive cycles of 3D printing and recycling were successfully shown. The suggested approach for extending additive manufacturing to carbon-neutral materials opens a new direction in the field of sustainable development. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Comprehensive pulsed electric field (PEF) system analysis for microalgae processing.
Buchmann, Leandro; Bloch, Robin; Mathys, Alexander
2018-06-07
Pulsed electric field (PEF) is an emerging nonthermal technique with promising applications in microalgae biorefinery concepts. In this work, the flow field in continuous PEF processing and its influencing factors were analyzed and energy input distributions in PEF treatment chambers were investigated. The results were obtained using an interdisciplinary approach that combined multiphysics simulations with ultrasonic Doppler velocity profiling (UVP) and rheological measurements of Arthrospira platensis suspensions as a case study for applications in the biobased industry. UVP enabled non-invasive validation of multiphysics simulations. A. platensis suspensions follow a non-Newtonian, shear-thinning behavior, and measurement data could be fitted with rheological functions, which were used as an input for fluid dynamics simulations. Within the present work, a comprehensive system characterization was achieved that will facilitate research in the field of PEF processing. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Golberg, Alexander; Sack, Martin; Teissie, Justin; Pataro, Gianpiero; Pliquett, Uwe; Saulis, Gintautas; Stefan, Töpfl; Miklavcic, Damijan; Vorobiev, Eugene; Frey, Wolfgang
2016-01-01
Fossil resources-free sustainable development can be achieved through a transition to bioeconomy, an economy based on sustainable biomass-derived food, feed, chemicals, materials, and fuels. However, the transition to bioeconomy requires development of new energy-efficient technologies and processes to manipulate biomass feed stocks and their conversion into useful products, a collective term for which is biorefinery. One of the technological platforms that will enable various pathways of biomass conversion is based on pulsed electric fields applications (PEF). Energy efficiency of PEF treatment is achieved by specific increase of cell membrane permeability, a phenomenon known as membrane electroporation. Here, we review the opportunities that PEF and electroporation provide for the development of sustainable biorefineries. We describe the use of PEF treatment in biomass engineering, drying, deconstruction, extraction of phytochemicals, improvement of fermentations, and biogas production. These applications show the potential of PEF and consequent membrane electroporation to enable the bioeconomy and sustainable development.
Microbiological aspects related to the feasibility of PEF technology for food pasteurization.
Saldaña, G; Álvarez, I; Condón, S; Raso, J
2014-01-01
Processing unit operations that seek to inactivate harmful microorganisms are of primary importance in ascertaining the safety of food. The capability of pulsed electric fields (PEF) to inactivate vegetative cells of microorganisms at temperatures below those used in thermal processing makes this technology very attractive as a nonthermal pasteurization process for the food industry. Commercial exploitation of this technology for food pasteurization requires the identification of the most PEF-resistant microorganisms that are of concern to public health. Then, the treatment conditions applicable at industrial scale that would reduce the population of these microorganisms to a level that guarantees food safety must be defined. The objective of this paper is to critically compile recent, relevant knowledge with the purpose of enhancing the feasibility of using PEF technology for food pasteurization and underlining the required research for designing PEF pasteurization processes.
Protoscolicidal and immunomodulatory activity of Ziziphora tenuior extract and its fractions.
Shahnazi, Mojtaba; Azadmehr, Abbas; Andalibian, Ammar; Hajiaghaee, Reza; Saraei, Mehrzad; Alipour, Mahmood
2016-11-01
To evaluate the scolicidal and immunomodulatory effect of the Ziziphora tenuior (Z. tenuior) extract and its fractions. Protoscolices were treated with six concentrations (3, 5, 10, 25, 50, and 100 mg/mL) of Z. tenuior extract and its fractions (ethanol, petroleum ether, ethyl acetate and chloroform) in periods of 10, 20, 30, 40, 50 and 60 min, and viability of protoscolices was evaluated using the 1.0% eosin. To examine the immunomodulatory effects of Ziziphora and its fractions on macrophage cells, the non-toxic concentration of extract and different fractions determined by MTT assay, and the Griess reaction was used to measure the level of nitrite as an indicator of nitric oxide by the macrophage cells in 10, 100 and 200 μg/mL in 24 h at 37 °C. In this study, the Z. tenuior extract at 10 mg/mL concentration was able to kill all protoscolices during 20 min. By increasing the concentration to 25 mg/mL, the scolicidal time reduced to 10 min. Regarding the effect of different fractions of Z. tenuior, the ethanolic fraction showed the highest scolicidal activity. The extract demonstrated an inhibitory effect on the activity of macrophages and reduced nitric oxide production. Although the petroleum ether and ethanolic fractions of the extract reduced nitric oxide production, nevertheless, this effect was only significant at 10 and 100 μg/mL concentrations (P < 0.05). The Z. tenuior extract and its fractions were effective against protoscolices yet the effect of total extract was considerable. Our findings indicates that the extract and its ethanolic and petroleum ether fractions could have anti-inflammatory properties. Copyright © 2016 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.
In vitro antimicrobial activity of ethanolic fractions of Cryptolepis sanguinolenta
2012-01-01
Background Following claims that some plants have antimicrobial activities against infectious microbes, the in vitro antimicrobial activities of different solvent fractions of ethanolic extract of Cryptolepis sanguinolenta were evaluated against eight standard bacteria and clinical isolates. Methods The solvent partitioning protocol involving ethanol, petroleum ether, chloroform, ethyl acetate and water, was used to extract various fractions of dried pulverized Cryptolepis sanguinolenta roots. Qualitative phyto-constituents screening was performed on the ethanol extract, chloroform fraction and the water fraction. The Kirby Bauer disk diffusion method was employed to ascertain the antibiogram of the test organisms while the agar diffusion method was used to investigate the antimicrobial properties of the crude plant extracts. The microplate dilution method aided in finding the MICs while the MBCs were obtained by the method of Nester and friends. The SPSS 16.0 version was used to analyze the percentages of inhibitions and bactericidal activities. Results The phytochemical screening revealed the presence of alkaloids, reducing sugars, polyuronides, anthocyanosides and triterpenes. The ethanol extract inhibited 5 out of 8 (62.5%) of the standard organisms and 6 out of 8 (75%) clinical isolates. The petroleum ether fraction inhibited 4 out of 8 (50%) of the standard microbes and 1 out of 8 (12.5%) clinical isolates. It was also observed that the chloroform fraction inhibited the growth of all the organisms (100%). Average inhibition zones of 14.0 ± 1.0 mm to 24.67 ± 0.58 mm was seen in the ethyl acetate fraction which halted the growth of 3 (37.5%) of the standard organisms. Inhibition of 7 (87.5%) of standard strains and 6 (75%) of clinical isolates were observed in the water fraction. The chloroform fraction exhibited bactericidal activity against all the test organisms while the remaining fractions showed varying degrees of bacteriostatic activity. Conclusion The study confirmed that fractions of Cryptolepis sanguinolenta have antimicrobial activity. The chloroform fraction had the highest activity, followed by water, ethanol, petroleum ether and ethyl acetate respectively. Only the chloroform fraction exhibited bactericidal activity and further investigations are needed to ascertain its safety and prospects of drug development. PMID:22709723
Anti-Helicobacter pylori activity of bioactive components isolated from Hericium erinaceus.
Liu, Jian-Hui; Li, Liang; Shang, Xiao-Dong; Zhang, Jun-Ling; Tan, Qi
2016-05-13
The fungus Hericium erinaceus (Bull.) Pers is used in Chinese traditional medicine to treat symptoms related to gastric ulcers. Different extracts from the fungus were assessed for anti-Helicobacter pylori activity to investigate the antibacterial activity of the ethanol extracts from H. erinaceus and verify the traditional indication of use. The fruiting bodies of H. erinaceus were concentrated with ethanol by HPD-100 macroporous resin and the whole extract was partitioned by petroleum ether and chloroform to afford fractions with using a silica gel column. Several pure compounds of petroleum ether extracts were obtained and analyzed using nuclear magnetic resonance (NMR). The activity of the extracts and fractions towards H. pylori was assessed by the microdilution assay and by the disk diffusion assay in vitro. From the most active fraction, two pure compounds were isolated and identified as the main components with anti-H. pylori activity from the fungus H. erinaceus. The cytotoxicity of these two compounds against the human erythroleu-kemia cell line K562 was also evaluated. The crude ethanol extracts from the fungus H. erinaceus were inhibitory to H. pylori. The petroleum ether extracts (PE1s, PE2s) and the chloroform extracts (TEs) demonstrated strong inhibition to H. pylori. The inhibition of H. pylori was observed through an agar dilution test with minimal inhibition concentration (MIC) values from 400μg/mL to 12.5µg/mL. Two pure compounds, 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone and 2,5-bis(methoxycarbonyl)terephthalic acid were isolated from the petroleum ether fractions and identified using (1)H NMR and (13)C NMR spectra analysis. The MIC value for 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone was 12.5-50µg/mL and the MIC value for 2,5-bis(methoxycarbonyl)terephthalic acid was 6.25-25µg/mL. Both two compounds showed weak cytotoxicity against K562 with IC50<200mM. This study revealed that the extracts from petroleum ether contribute to the anti-H. pylori activity. The compounds obtained from petroleum ether extracts, 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone and 2,5-bis(methoxycarbonyl)terephthalic acid, inhibit the growth of H. pylori. Copyright © 2016. Published by Elsevier Ireland Ltd.
Wouters, Patrick C.; Bos, Ad P.; Ueckert, Joerg
2001-01-01
Membrane permeabilization due to pulsed electric field (PEF) treatment of gram-positive Lactobacillus cells was investigated by using propidium iodide uptake and single-cell analysis with flow cytometry. Electric field strength, energy input, treatment time, and growth phase affected membrane permeabilization of Lactobacillus plantarum during PEF treatment. A correlation between PEF inactivation and membrane permeabilization of L. plantarum cells was demonstrated, whereas no relationship was observed between membrane permeabilization and heat inactivation. The same results were obtained with a Lactobacillus fermentum strain, but the latter organism was more PEF resistant and exhibited less membrane permeabilization, indicating that various bacteria have different responses to PEF treatment. While membrane permeabilization was the main factor involved in the mechanism of inactivation, the growth phase and the acidity of the environment also influenced inactivation. By using flow cytometry it was possible to sort cells in the L. plantarum population based on different cell sizes and shapes, and the results were confirmed by image analysis. An apparent effect of morphology on membrane permeabilization was observed, and larger cells were more easily permeabilized than smaller cells. In conclusion, our results indicate that the ability of PEF treatment to cause membrane permeabilization is an important factor in determining inactivation. This finding should have an effect on the final choice of the processing parameters used so that all microorganisms can be inactivated and, consequently, on the use of PEF treatment as an alternative method for preserving food products. PMID:11425727
Biophysical Studies of Nanosecond Pulsed Electric Field Induced Cell Membrane Permeabilization
NASA Astrophysics Data System (ADS)
Wu, Yu-Hsuan
Nanosecond megavolts-per-meter pulsed electric field (nsPEF) offers a non-invasive manipulation of intracellular organelles and functions of biological cells. Accordingly, nsPEF is a potential technique for biophysical research and cancer therapy, and is of growing interest. Although, the application of nsPEF has shown electroperturbation on cell plasma membranes and intracellular membranes as well, the mechanisms underlying the electropermeabilization are still not clear. In this thesis, we systematically study nsPEFs (5 and 30 ns) induced membrane permeability change in biological cell in-vitro with different pulse parameters. In Chapter 3, we investigate the nsPEF-induced intracellular membrane permeabilization of mitochondria which play key roles in activating apoptosis in mammalian cells. The results show the evidences of nsPEF-induced membrane permeability increase in mitochondria, and suggest that nsPEF is a potential technology for cancer cell ablation without delivery of drug or gene into cells. In Chapter 2, 4 and 6, we study the properties of nsPEF-induced plasma membrane permeabilization. In the beginning, the change of plasma membrane permeability is studied by uptake of YO-PRO-1 and propidium iodide, fluorescent dyes specifically used as indicators of plasma membrane permeabilization. However, the detection is limited by the fluorescent emission efficiency and detector capability. To increase the detection sensitivity, we later develop a method based on cell volume change due to regulation of osmotic balance that causes water and small ions transport through plasma membrane. We find that even a single 10 MV/m pulse of 5 ns duration produces measureable cell swelling. The results demonstrate that cell swelling is susceptible to nsPEF and can detect membrane permeabilization more easily and precisely than fluorescent dyes. We compare the effects of different pulse parameters (pulse duration, pulse number, electric field amplitude and pulse repetition rate) on electropermeabilization. The effects of chemical agents that either promote (H2O2) or inhibit (lanthanide ions and Hg2+) electropermeabilization are also studied. To characterize the population of pores created by nsPEFs, we isoosmotically substitute different size of neutral molecules in the pulsing medium, and estimate pore size by analyzing cell volume changes that result from the permeation of these substituted molecules through the plasma membrane of Jurkat T lymphoblasts. The basis of this method is regulation of osmotic balance across the plasma membrane as well. We find that most pores opened by 5-100 5 ns pulses in plasma memebrane of Jurkat T lymphoblasts have diameter between 0.7-0.9 nm. In Chapter 5, we report the design and construction of a delivery system for nsPEF. We integrate a pair of delicately fabricated tungsten wire electrodes spaced 100 mum, a solid-state high-voltage nanosecond pulse generator and a fluorescent microscope coupling with a fast and sensitive digital recording camera. This system enables real-time biophotonic investigations of the nsPEF-induced biological responses of living mammalian cells in-vitro.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sulaeman, M. Y.; Widita, R.
2014-09-30
Purpose: Non-ionizing radiation therapy for cancer using pulsed electric field with high intensity field has become an interesting field new research topic. A new method using nanosecond pulsed electric fields (nsPEFs) offers a novel means to treat cancer. Not like the conventional electroporation, nsPEFs able to create nanopores in all membranes of the cell, including membrane in cell organelles, like mitochondria and nucleus. NsPEFs will promote cell death in several cell types, including cancer cell by apoptosis mechanism. NsPEFs will use pulse with intensity of electric field higher than conventional electroporation, between 20–100 kV/cm and with shorter duration of pulsemore » than conventional electroporation. NsPEFs requires a generator to produce high voltage pulse and to achieve high intensity electric field with proper pulse width. However, manufacturing cost for creating generator that generates a high voltage with short duration for nsPEFs purposes is highly expensive. Hence, the aim of this research is to obtain the low cost generator design that is able to produce a high voltage pulse with nanosecond width and will be used for nsPEFs purposes. Method: Cockcroft-Walton multiplier circuit will boost the input of 220 volt AC into high voltage DC around 1500 volt and it will be combined by a series of power MOSFET as a fast switch to obtain a high voltage with nanosecond pulse width. The motivation using Cockcroft-Walton multiplier is to acquire a low-cost high voltage DC generator; it will use capacitors and diodes arranged like a step. Power MOSFET connected in series is used as voltage divider to share the high voltage in order not to damage them. Results: This design is expected to acquire a low-cost generator that can achieve the high voltage pulse in amount of −1.5 kV with falltime 3 ns and risetime 15 ns into a 50Ω load that will be used for nsPEFs purposes. Further detailed on the circuit design will be explained at presentation.« less
Delsart, C; Grimi, N; Boussetta, N; Miot Sertier, C; Ghidossi, R; Vorobiev, E; Mietton Peuchot, M
2016-01-01
In this study, pulsed-electric fields (PEF) and high-voltage electrical discharges (HVED) are proposed as new techniques for the microbial stabilization of red wines before bottling. The efficiency of the treatment was then evaluated. PEF and HVED-treatments have been applied to wine for the inactivation of Oenococcus oeni CRBO 9304, O. oeni CRBO 0608, Pediococcus parvulus CRBO 2.6 and Brettanomyces bruxellensis CB28. Different treatment times (1, 2, 4, 6, 8 and 10 ms) were used at 20 kV cm(-1) for the PEF treatments and at 40 kV for the HVED treatments, which correspond to applied energies from 80 to 800 kJ l(-1) . The effects of the treatments on the microbial inactivation rate and on various characteristics of red wines (phenolic composition, chromatic characteristics and physico-chemical parameters) were measured. The application of PEF or HVED treatments on red wine allowed the inactivation of alteration yeasts (B. bruxellensis CB28) and bacteria (O. oeni CRBO 9304, O. oeni CRBO 0608 and P. parvulus CRBO 2.6). The electric discharges at 40 kV were less effective than the PEF even after 10 ms of treatments. Indeed, 4 ms of PEF treatment at 20 kV cm(-1) were sufficient to inactivate all micro-organisms present in the wines. Also, the use of PEF had no negative impact on the composition of wines compared to the HVED treatments. Contrary to PEF, the phenolics compounds were degraded after the HVED treatment and the physico-chemical composition of wine were modified with HVED. PEF technology seems to be an interesting alternative to stabilize microbiologically wines before bottling and without modifying their composition. This process offers many advantages for winemakers: no chemical inputs, low energy consumption (320 kJ l(-1) ), fast (treatment time of 4 ms) and athermal (ΔT ≈ 10°C). © 2015 The Society for Applied Microbiology.
Del Río, José C; Prinsen, Pepijn; Cadena, Edith M; Martínez, Ángel T; Gutiérrez, Ana; Rencoret, Jorge
2016-05-01
Two types of lignins occurred in different lignin-carbohydrate fractions, a lignin enriched in syringyl units, less condensed, preferentially associated with xylans, and a lignin with more guaiacyl units, more condensed, associated with glucans. Lignin-carbohydrate complexes (LCC) were isolated from the fibers of sisal (Agave sisalana) and abaca (Musa textilis) according to a plant biomass fractionation procedure recently developed and which was termed as "universally" applicable to any type of lignocellulosic material. Two LCC fractions, namely glucan-lignin (GL) and xylan-lignin (XL), were isolated and differed in the content and composition of carbohydrates and lignin. In both cases, GL fractions were enriched in glucans and comparatively depleted in lignin, whereas XL fractions were depleted in glucans, but enriched in xylans and lignin. Analysis by two-dimensional Nuclear Magnetic Resonance (2D-NMR) and Derivatization Followed by Reductive Cleavage (DFRC) indicated that the XL fractions were enriched in syringyl (S)-lignin units and β-O-4' alkyl-aryl ether linkages, whereas GL fractions have more guaiacyl (G)-lignin units and less β-O-4' alkyl-aryl ether linkages per lignin unit. The data suggest that the structural characteristics of the lignin polymers are not homogeneously distributed within the same plant and that two different lignin polymers with different composition and structure might be present. The analyses also suggested that acetates from hemicelluloses and the acyl groups (acetates and p-coumarates) attached to the γ-OH of the lignin side chains were extensively hydrolyzed and removed during the LCC fractionation process. Therefore, caution must be paid when using this fractionation approach for the structural characterization of plants with acylated hemicelluloses and lignins. Finally, several chemical linkages (phenylglycosides and benzyl ethers) could be observed to occur between lignin and xylans in these plants.
PHYSICAL AND BIOLOGICAL PROPERTIES OF INFLUENZA VIRUS COMPONENTS OBTAINED AFTER ETHER TREATMENT
Davenport, Fred M.; Rott, Rudolf; Schäfer, Werner
1960-01-01
The Rostock strain of fowl plague, the swine, A, A', and Asian strains of influenza A as well as their hemagglutinin and internal s antigen subunits obtained after ether splitting, were found to be morphologically indistinguishable when examined simultaneously. Hemagglutinin fractions reacted in a highly strain specific manner when tested by hemagglutination inhibition or by complement fixation using sera obtained after infection. With the same sera internal s antigen fractions were shown to be serologically distinguishable by complement fixation. This observation may stimulate interest in the feasibility of employing immunologic techniques for the study of nucleoproteins. The significance of the findings reported is discussed. PMID:13719952
Moreira, Francisca C; Soler, J; Alpendurada, M F; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P
2016-11-15
This study focuses on the degradation of pharmaceuticals from a municipal wastewater after secondary treatment by applying various advanced oxidation processes (AOPs) and electrochemical AOPs (EAOPs) like UVC, H 2 O 2 /UVC, anodic oxidation (AO), AO with electrogenerated H 2 O 2 (AO-H 2 O 2 ), AO-H 2 O 2 /UVC and photoelectro-Fenton (PEF) using either UVC radiation (PEF-UVC) or UVA radiation (PEF-UVA). The municipal wastewater after secondary treatment was spiked with 5.0 mg L -1 of trimethoprim (TMP) antibiotic. The efficiency of processes to remove TMP followed the order UVC < AO-H 2 O 2 < PEF-UVA < AO ≈ PEF-UVC < AO-H 2 O 2 /UVC < PEF-UVA (pH = 2.8) < H 2 O 2 /UVC ≈ PEF-UVC (pH = 2.8), using neutral pH, except when identified. While the UVC radiation alone led to a very low TMP removal, the H 2 O 2 /UVC process promoted a very high TMP degradation due to the production of hydroxyl radicals (OH) by H 2 O 2 cleavage. In the AO-H 2 O 2 /UVC process, the electrogeneration of H 2 O 2 can avoid the risks associated with the transportation, storage and manipulation of this oxidant and, furthermore, OH at the anode surface are also formed. Nevertheless, low contents of H 2 O 2 were detected mainly at the beginning of the reaction, leading to a lower initial reaction rate when compared with the H 2 O 2 /UVC system. In the PEF-UVC, the addition of iron at neutral pH led to the visible formation of insoluble iron oxides that can filter the light. At pH 2.8, the iron remained dissolved, thereby promoting the Fenton's reaction and increasing the organics removal. The UVA-driven processes showed limited efficiency when compared with those using UVC light. For all processes with H 2 O 2 electrogeneration, the active chlorine species can be scavenged by the H 2 O 2 , diminishing the efficiency of the processes. This can explain the lower efficiency of AO-H 2 O 2 when compared with AO. Moreover, the degradation of the MWWTP effluent spiked with 18 pharmaceuticals in μg L -1 during AO process was assessed as well as the influence of the following operational variables on the process efficiency: (i) H 2 O 2 concentration on H 2 O 2 /UVC, (ii) current density on AO, AO-H 2 O 2 , AO-H 2 O 2 /UVC, PEF-UVC and PEF-UVA, and (iii) pH on PEF-UVA. Copyright © 2016 Elsevier Ltd. All rights reserved.
Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties.
Zhang, Zhi-Hong; Zeng, Xin-An; Brennan, Charles S; Brennan, Margaret; Han, Zhong; Xiong, Xia-Yu
2015-10-13
In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests.
Puértolas, Eduardo; Martínez de Marañón, Iñigo
2015-01-15
The impact of the use of pulsed electric field (PEF) technology on Arroniz olive oil production in terms of extraction yield and chemical and sensory quality has been studied at pilot scale in an industrial oil mill. The application of a PEF treatment (2 kV/cm; 11.25 kJ/kg) to the olive paste significantly increased the extraction yield by 13.3%, with respect to a control. Furthermore, olive oil obtained by PEF showed total phenolic content, total phytosterols and total tocopherols significantly higher than control (11.5%, 9.9% and 15.0%, respectively). The use of PEF had no negative effects on general chemical and sensory characteristics of the olive oil, maintaining the highest quality according to EU legal standards (EVOO; extra virgin olive oil). Therefore, PEF could be an appropriate technology to improve olive oil yield and produce EVOO enriched in human-health-related compounds, such as polyphenols, phytosterols and tocopherols. Copyright © 2014 Elsevier Ltd. All rights reserved.
Yu, Yuanshan; Jin, Tony Z; Fan, Xuetong; Wu, Jijun
2018-01-15
Fresh blueberries were pretreated by pulsed electric fields (PEF) or thermal pretreatment and then were subject to osmotic dehydration. The changes in contents of anthocyanins, predominantly phenolic acids and flavonols, total phenolics, polyphenol oxidase (PPO) activity and antioxidant activity in the blueberry samples during pretreatment and osmotic dehydration were investigated. Biochemical degradation and physical migration of these nutritive compounds from fruits to osmotic solutions were observed during the pretreatments and osmotic dehydration. PEF pretreated samples had the least degradation loss but the most migration loss of these compounds compared to thermally pretreated and control samples. Higher rates of water loss and solid gain during osmotic dehydration were also obtained by PEF pretreatment, reducing the dehydration time from 130 to 48h. PEF pretreated and dehydrated fruits showed superior appearance to thermally pretreated and control samples. Therefore, PEF pretreatment is a preferred technology that balances nutritive quality, appearance, and dehydration rate. Published by Elsevier Ltd.
Pankiewicz, Urszula; Sujka, Monika; Włodarczyk-Stasiak, Marzena; Mazurek, Artur; Jamroz, Jerzy
2014-08-15
Cultures of Saccharomyces cerevisiae were treated with PEF to improve simultaneous accumulation of magnesium and zinc ions in the biomass. The results showed that the ions concentration in the medium and their mutual interactions affect accumulation in cells. Increasing the concentration of one ion in the medium reduced the accumulation of the second one, in the control as well as in the cells treated with PEF. Under optimized conditions, that is, on 15 min exposure of the 20 h grown culture to PEF of 5.0 kV/cm and 20 μs pulse width, accumulation of magnesium and zinc in yeast biomass reached maximum levels of 2.85 and 11.41 mg/gd.m., respectively, To summarize, optimization of ion pair concentration and PEF parameters caused a 1.5 or 2-fold increase of magnesium and zinc accumulation, respectively, in S. cerevisiae. Copyright © 2014 Elsevier Ltd. All rights reserved.
Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties
Zhang, Zhi-Hong; Zeng, Xin-An; Brennan, Charles S.; Brennan, Margaret; Han, Zhong; Xiong, Xia-Yu
2015-01-01
In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests. PMID:26473846
USDA-ARS?s Scientific Manuscript database
This paper investigated the feasibility for pasteurizing raw pomegranate juice in a commercial scale pulsed electric field (PEF) system. The juice was processed in a commercial scale PEF processing system at 35 and 38 kV/cm for 281 µs at 55 degree C with a flow rate of 100 L/h. Effect of PEF process...
Pulsed Electromagnetic Field Assisted in vitro Electroporation: A Pilot Study
NASA Astrophysics Data System (ADS)
Novickij, Vitalij; Grainys, Audrius; Lastauskienė, Eglė; Kananavičiūtė, Rūta; Pamedytytė, Dovilė; Kalėdienė, Lilija; Novickij, Jurij; Miklavčič, Damijan
2016-09-01
Electroporation is a phenomenon occurring due to exposure of cells to Pulsed Electric Fields (PEF) which leads to increase of membrane permeability. Electroporation is used in medicine, biotechnology, and food processing. Recently, as an alternative to electroporation by PEF, Pulsed ElectroMagnetic Fields (PEMF) application causing similar biological effects was suggested. Since induced electric field in PEMF however is 2-3 magnitudes lower than in PEF electroporation, the membrane permeabilization mechanism remains hypothetical. We have designed pilot experiments where Saccharomyces cerevisiae and Candida lusitaniae cells were subjected to single 100-250 μs electrical pulse of 800 V with and without concomitant delivery of magnetic pulse (3, 6 and 9 T). As expected, after the PEF pulses only the number of Propidium Iodide (PI) fluorescent cells has increased, indicative of membrane permeabilization. We further show that single sub-millisecond magnetic field pulse did not cause detectable poration of yeast. Concomitant exposure of cells to pulsed electric (PEF) and magnetic field (PMF) however resulted in the increased number PI fluorescent cells and reduced viability. Our results show increased membrane permeability by PEF when combined with magnetic field pulse, which can explain electroporation at considerably lower electric field strengths induced by PEMF compared to classical electroporation.
Pulsed Electromagnetic Field Assisted in vitro Electroporation: A Pilot Study
Novickij, Vitalij; Grainys, Audrius; Lastauskienė, Eglė; Kananavičiūtė, Rūta; Pamedytytė, Dovilė; Kalėdienė, Lilija; Novickij, Jurij; Miklavčič, Damijan
2016-01-01
Electroporation is a phenomenon occurring due to exposure of cells to Pulsed Electric Fields (PEF) which leads to increase of membrane permeability. Electroporation is used in medicine, biotechnology, and food processing. Recently, as an alternative to electroporation by PEF, Pulsed ElectroMagnetic Fields (PEMF) application causing similar biological effects was suggested. Since induced electric field in PEMF however is 2–3 magnitudes lower than in PEF electroporation, the membrane permeabilization mechanism remains hypothetical. We have designed pilot experiments where Saccharomyces cerevisiae and Candida lusitaniae cells were subjected to single 100–250 μs electrical pulse of 800 V with and without concomitant delivery of magnetic pulse (3, 6 and 9 T). As expected, after the PEF pulses only the number of Propidium Iodide (PI) fluorescent cells has increased, indicative of membrane permeabilization. We further show that single sub-millisecond magnetic field pulse did not cause detectable poration of yeast. Concomitant exposure of cells to pulsed electric (PEF) and magnetic field (PMF) however resulted in the increased number PI fluorescent cells and reduced viability. Our results show increased membrane permeability by PEF when combined with magnetic field pulse, which can explain electroporation at considerably lower electric field strengths induced by PEMF compared to classical electroporation. PMID:27634482
Yin, Shengyong; Chen, Xinhua; Xie, Haiyang; Zhou, Lin; Guo, Danjing; Xu, Yuning; Wu, Liming; Zheng, Shusen
2016-08-15
Previous studies showed nanosecond pulsed electric field (nsPEF) can ablate solid tumors including hepatocellular carcinoma (HCC) but its effect on cell membrane is not fully understood. We hypothesized nsPEF disrupt the microdomains on outer-cellular membrane with direct mechanical force and as a result the plasma membrane permeability increases to facilitate the small molecule intake. Three HCC cells were pulsed one pulse per minute, an interval longer than nanopore resealing time. The cationized ferritin was used to mark up the electronegative microdomains, propidium iodide (PI) for membrane permeabilization, energy dispersive X-ray spectroscopy (EDS) for the negative cell surface charge and cisplatin for inner-cellular cytotoxicity. We demonstrated that the ferritin marked-microdomain and negative cell surface charge were disrupted by nsPEF caused-mechanical force. The cell uptake of propidium and cytotoxicity of DNA-targeted cisplatin increased with a dose effect. Cisplatin gains its maximum inner-cellular cytotoxicity when combining with nsPEF stimulation. We conclude that nsPEF disrupt the microdomains on the outer cellular membrane directly and increase the membrane permeabilization for PI and cisplatin. The microdomain disruption and membrane infiltration changes are caused by the mechanical force from the changes of negative cell surface charge. Copyright © 2016 Elsevier Inc. All rights reserved.
Chen, Xinhua; Zhang, Ruiqing; Aji, Tuerganaili; Shao, Yingmei; Chen, Yonggang; Wen, Hao
2017-07-03
The nanosecond pulsed electric field (nsPEF) is investigated as an alternative plan for benign hepatic hydatid cyst. Altogether 72 C57B6 mice were included. Normal group (n = 12) had no parasite injection and the other 60 mice were used to induce hydatid cyst in liver by injecting protoscolices in portal vein. The liver hydatid cysts were exposed to nsPEF with different doses and then follow up. The standard surgery was performed as positive control. The hydatid cyst growth was monitored by ultrasound; the morphology was checked by gross anatomy and pathology was tested by H&E stain. In nsPEF-treated groups no hepatic failure nor bleeding were observed. As a comparison, in the surgery group, high post-treatment complications occurred (50%). Significant parasite growth inhibition was seen in high nsPEF dose group as compared with control group (P < 0.05). Pathological analysis confirmed destruction of hydatid cyst with sharp demarcation defined by the electrodes. Laboratory analysis showed nsPEF stimulated a time-dependent infection and recoverable liver function. The traumatic reactions defined by white blood count was significant lower than surgery groups (P < 0.05).Preliminary studies demonstrate nsPEF ablation can be applied on hepatic hydatid by inhibiting parasite growth, destructing the cyst and stimulating infections.
NASA Astrophysics Data System (ADS)
Golovnev, Nicolay N.; Molokeev, Maxim S.; Lesnikov, Maxim K.; Sterkhova, Irina V.; Atuchin, Victor V.
2017-12-01
Three new salts of pefloxacin (PefH) with thiobarbituric (H2tba) and barbituric (H2ba) acids, pefloxacinium 2-thiobarbiturate trihydrate, PefH2(Htba)·3H2O (1), pefloxacinium 2-thiobarbiturate, PefH2(Htba) (2) and bis(pefloxacinium barbiturate) hydrate, (PefH2)2(Hba)2·2.56H2O (3) are synthesized and structurally characterized by the X-ray single-crystal diffraction. The structures of 1-3 contain intramolecular hydrogen bonds Csbnd H⋯F, Osbnd H⋯O. Intermolecular hydrogen bonds Nsbnd H⋯O and Osbnd H⋯O form a 2D plane network in 1. In 2 and 3, intermolecular hydrogen bonds Nsbnd H⋯O form the infinite chains. In 1-3, the Htba- and Hba- ions are connected with PefH2+ only by one intermolecular hydrogen bond Nsbnd H⋯O. In 2 and 3, two Htba- and Hba- ions are connected by two hydrogen bonds Nsbnd H⋯O. These pairs form infinite chains. All three structures are stabilized by the π-π interactions of the head-to-tail type between PefH2+ ions. Compounds 2 and 3 are characterized by powder XRD, TG-DSC and FT-IR.
Wei, Kai; Li, Wei; Gao, Shan; Ji, Bin; Zang, Yating; Su, Bo; Wang, Kaile; Yao, Maosheng; Zhang, Jue; Wang, Jinglin
2016-01-05
Ricin is one of the most toxic and easily produced plant protein toxin extracted from the castor oil plant, and it has been classified as a chemical warfare agent. Here, nanosecond pulsed electric fields (nsPEFs) at 30 kV/cm (pulse durations: 10 ns, 100 ns, and 300 ns) were applied to inactivating ricin up to 4.2 μg/mL. To investigate the efficacy, cells and mice were tested against the ricin treated by the nsPEFs via direct intraperitoneal injection and inhalation exposure. Results showed that nsPEFs treatments can effectively reduce the toxicity of the ricin. Without the nsPEFs treatment, 100% of mice were killed upon the 4 μg ricin injection on the first day, however 40% of the mice survived the ricin treated by the nsPEFs. Compared to injection, inhalation exposure even with higher ricin dose required longer time to observe mice fatality. Pathological observations revealed damages to heart, lung, kidney, and stomach after the ricin exposure, more pronounced for lung and kidney including severe bleeding. Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) and circular dichroism (CD) analyses revealed that although the primary structure of ricin was not altered, its secondary structures (beta-sheet and beta-turn) underwent transition upon the nsPEFs treatment.
Tsurikisawa, Naomi; Saito, Akemi; Oshikata, Chiyako; Yasueda, Hiroshi; Akiyama, Kazuo
2016-10-01
We investigated the best strategy for adult asthmatics to avoid exposure to Dermatophagoides group (Der-1) allergens. Adult atopic asthmatics (n = 111) followed a 32-item checklist for avoiding Der-1 allergen exposure. Twenty-five patients were excluded through incomplete sampling; 50 remaining patients encased their pillows/futons/mattresses in microfine-fiber covers, 13 used vacuum cleaners with dust-mite-collection nozzles, and 23 acted as non-intervention controls. During August-October 2010 and August-October 2011, dust samples were collected in Petri dishes placed in bedrooms for 2 weeks and from mattresses/futons by using adhesive tape on one morning. A Der-1 level decrease was defined as a mean 2011 Der-1 level of <1 as a ratio of the 2010 level on tape or Petri dish samples. We analyzed the associations between Der-1 level change (by ELISA) and % weekly variability in peak expiratory flow (PEF) or fraction of exhaled nitric oxide (FeNO) after intervention. Der-1 levels decreased significantly in the covers group but not the vacuuming group. FeNO levels and PEF variability were unchanged in both groups. In patients whose Petri dish or tape samples showed decreased Der-1 levels, the % PEF variability was lower in 2011 than in 2010, but FeNO levels were unchanged. Three interventions (vacuuming all family members' mattress/futon surfaces at least weekly or after exposure of the futons to sunlight, and floor wiping before vacuuming), plus using covers, were the most effective management strategy in reducing Der-1 levels. This environmental and bedding maintenance program may help manage adult atopic asthma.
Bobinaitė, Ramunė; Pataro, Gianpiero; Lamanauskas, Nerijus; Šatkauskas, Saulius; Viškelis, Pranas; Ferrari, Giovanna
2015-09-01
The influence of Pulsed Electric Field (PEF) pre-treatment of blueberry fruits (Vaccinium myrtillus L.), both on the extraction yield and antioxidant properties of juice obtained by pressing and on the on the recovery of bioactive compounds from berry by-products (press cake) by extraction with solvent, was investigated. PEF treatments carried out at field strengths of 1, 3, and 5 kV/cm and an energy input of 10 kJ/kg achieved a cell disintegration index (Z p ) of 0.70, 0.80, and 0.87, respectively. Mechanical pressing (1.32 bar for 8 min) of PEF-treated berries (1, 3, and 5 kV/cm at 10 kJ/kg) significantly increased the juice yield (+28 %) compared with the untreated sample. The juice obtained from PEF pre-treated berries also had a significantly higher total phenolic content (+43 %), total anthocyanin content (+60 %) and antioxidant activity (+31 %). However, PEF treatment intensity higher than 1 kV/cm did not significantly improve the quantitative or qualitative characteristics of the juice. Compared to the untreated sample, higher amounts of total phenolics (+63 %), total athocyanins (+78 %) and antioxidant activity (+65 %) were detected in the press cake extracts. PEF treatment of higher intensity resulted in better extractability of bioactive compounds from blueberry press cake. The results obtained from this study demonstrate the potential of PEF as a mild pre-treatment method to improve the efficiency of the industrial processing of berry fruits.
The accuracy of portable peak flow meters.
Miller, M R; Dickinson, S A; Hitchings, D J
1992-11-01
The variability of peak expiratory flow (PEF) is now commonly used in the diagnosis and management of asthma. It is essential for PEF meters to have a linear response in order to obtain an unbiased measurement of PEF variability. As the accuracy and linearity of portable PEF meters have not been rigorously tested in recent years this aspect of their performance has been investigated. The response of several portable PEF meters was tested with absolute standards of flow generated by a computer driven, servo controlled pump and their response was compared with that of a pneumotachograph. For each device tested the readings were highly repeatable to within the limits of accuracy with which the pointer position can be assessed by eye. The between instrument variation in reading for six identical devices expressed as a 95% confidence limit was, on average across the range of flows, +/- 8.5 l/min for the Mini-Wright, +/- 7.9 l/min for the Vitalograph, and +/- 6.4 l/min for the Ferraris. PEF meters based on the Wright meter all had similar error profiles with overreading of up to 80 l/min in the mid flow range from 300 to 500 l/min. This overreading was greatest for the Mini-Wright and Ferraris devices, and less so for the original Wright and Vitalograph meters. A Micro-Medical Turbine meter was accurate up to 400 l/min and then began to underread by up to 60 l/min at 720 l/min. For the low range devices the Vitalograph device was accurate to within 10 l/min up to 200 l/min, with the Mini-Wright overreading by up to 30 l/min above 150 l/min. Although the Mini-Wright, Ferraris, and Vitalograph meters gave remarkably repeatable results their error profiles for the full range meters will lead to important errors in recording PEF variability. This may lead to incorrect diagnosis and bias in implementing strategies of asthma treatment based on PEF measurement.
The accuracy of portable peak flow meters.
Miller, M R; Dickinson, S A; Hitchings, D J
1992-01-01
BACKGROUND: The variability of peak expiratory flow (PEF) is now commonly used in the diagnosis and management of asthma. It is essential for PEF meters to have a linear response in order to obtain an unbiased measurement of PEF variability. As the accuracy and linearity of portable PEF meters have not been rigorously tested in recent years this aspect of their performance has been investigated. METHODS: The response of several portable PEF meters was tested with absolute standards of flow generated by a computer driven, servo controlled pump and their response was compared with that of a pneumotachograph. RESULTS: For each device tested the readings were highly repeatable to within the limits of accuracy with which the pointer position can be assessed by eye. The between instrument variation in reading for six identical devices expressed as a 95% confidence limit was, on average across the range of flows, +/- 8.5 l/min for the Mini-Wright, +/- 7.9 l/min for the Vitalograph, and +/- 6.4 l/min for the Ferraris. PEF meters based on the Wright meter all had similar error profiles with overreading of up to 80 l/min in the mid flow range from 300 to 500 l/min. This overreading was greatest for the Mini-Wright and Ferraris devices, and less so for the original Wright and Vitalograph meters. A Micro-Medical Turbine meter was accurate up to 400 l/min and then began to underread by up to 60 l/min at 720 l/min. For the low range devices the Vitalograph device was accurate to within 10 l/min up to 200 l/min, with the Mini-Wright overreading by up to 30 l/min above 150 l/min. CONCLUSION: Although the Mini-Wright, Ferraris, and Vitalograph meters gave remarkably repeatable results their error profiles for the full range meters will lead to important errors in recording PEF variability. This may lead to incorrect diagnosis and bias in implementing strategies of asthma treatment based on PEF measurement. PMID:1465746
Crescenti, Anna; Puiggròs, Francesc; Colomé, Arnau; Poch, Josep Antón; Caimari, Antoni; Bas, Josep Maria; Boqué, Noemí; Arola, Lluís
2015-12-01
To determine the effect of a botanical formulation of Herniaria glabra, Agropyron repens, Equisetum arvense, and Sambucus nigra as a preventive agent in an experimentally induced nefrolithiasis model in rats. Six groups of six Wistar male rats each were induced for nefrolithiasis by treatment with 0.75% ethylene glycol (EG) and 1% ammonium chloride for three days and then EG only for 15 days. One group was treated with placebo (control group) and the other groups (treated groups) were treated with 30 mg/Kg, 60 mg/Kg, 125 mg/Kg, 250 mg/Kg and 500 mg/Kg of the plant extract formulation (PEF). 24-h urine and water samples were collected one day before EG administration and at 7, 13 and 18 days to determine diuresis, crystalluria and urine biochemistry. The kidneys were removed for histological analysis. The phytochemical characterization of PEF and each of its component plant extracts was performed using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Animals treated with 125 mg/Kg of the PEF had statistically significantly lower calcium oxalate crystals deposits content compared to the control group. All PEF doses statistically significantly decreased the number of microcalcifications compared to the control group. Furthermore, the number of kidneys affected by subcapsular fibrosis was statistically significantly higher in control group than in treated groups with the PEF. The diuresis of the 125 mg/Kg and 500 mg/Kg PEF-treated groups was statistically significantly higher than that of the control group. A phytochemical analysis demonstrated the presence of flavonoids, dicarboxylic acids and saponins. Treatment with PEF prevents deposits of calcium oxalate crystals formation and of microcalcifications in the kidney, and reduces the risk of fibrosis subcapsular. 125 mg/Kg of PEF is the dose that has a greater effect on the studied parameters.
Cationic peptide exposure enhances pulsed-electric-field-mediated membrane disruption.
Kennedy, Stephen M; Aiken, Erik J; Beres, Kaytlyn A; Hahn, Adam R; Kamin, Samantha J; Hagness, Susan C; Booske, John H; Murphy, William L
2014-01-01
The use of pulsed electric fields (PEFs) to irreversibly electroporate cells is a promising approach for destroying undesirable cells. This approach may gain enhanced applicability if the intensity of the PEF required to electrically disrupt cell membranes can be reduced via exposure to a molecular deliverable. This will be particularly impactful if that reduced PEF minimally influences cells that are not exposed to the deliverable. We hypothesized that the introduction of charged molecules to the cell surfaces would create regions of enhanced transmembrane electric potential in the vicinity of each charged molecule, thereby lowering the PEF intensity required to disrupt the plasma membranes. This study will therefore examine if exposure to cationic peptides can enhance a PEF's ability to disrupt plasma membranes. We exposed leukemia cells to 40 μs PEFs in media containing varying concentrations of a cationic peptide, polyarginine. We observed the internalization of a membrane integrity indicator, propidium iodide (PI), in real time. Based on an individual cell's PI fluorescence versus time signature, we were able to determine the relative degree of membrane disruption. When using 1-2 kV/cm, exposure to >50 μg/ml of polyarginine resulted in immediate and high levels of PI uptake, indicating severe membrane disruption, whereas in the absence of peptide, cells predominantly exhibited signatures indicative of no membrane disruption. Additionally, PI entered cells through the anode-facing membrane when exposed to cationic peptide, which was theoretically expected. Exposure to cationic peptides reduced the PEF intensity required to induce rapid and irreversible membrane disruption. Critically, peptide exposure reduced the PEF intensities required to elicit irreversible membrane disruption at normally sub-electroporation intensities. We believe that these cationic peptides, when coupled with current advancements in cell targeting techniques will be useful tools in applications where targeted destruction of unwanted cell populations is desired.
Agu, Kingsley C; Okolie, Paulinus N
2017-09-01
Numerous bioactive compounds and phytochemicals have been reported to be present Annona muricata (Soursop). Some of these chemical compounds have been linked to the ethnomedicinal properties of the plant and its antioxidant properties. The aim of this study was to assess the proximate composition, phytochemical constituents and in vitro antioxidant properties of A. muricata using standard biochemical procedures. The defatted Annona muricata crude methanolic extracts of the different parts of the plant were used for the estimation of proximate composition and phytochemical screening. The crude methanolic extracts of the different parts of the plant were also fractionated using solvent-solvent partitioning. Petroleum ether, chloroform, ethyl acetate, methanol, and methanol-water (90:10) were the solvents used for the fractionation. The different fractions obtained were then used to perform in vitro antioxidant analyses including, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, ferric reducing properties, and hydroxyl radical scavenging ability. The leaf methanolic extract had a higher lipid content, whereas its chloroform fraction demonstrated a better ability to quench DPPH free radical. The root-bark methanol-water, leaf methanol, fruit pulp chloroform, and leaf petroleum ether fractions demonstrated potent ferric reducing properties. The leaf and stem-bark petroleum ether fractions demonstrated better hydroxyl-free radical scavenging abilities. The leaf and fruit pulp of Annona muricata have a very potent antioxidant ability compared to the other parts of the plant. This can be associated with the rich phytochemicals and other phytoconstituents like phenols, flavonoids, alkaloids, and essential lipids, etc. Significant correlations were observed between the antioxidant status and phytochemicals present. These results thus suggest that some of the reported ethnomedicinal properties of this plant could be due to its antioxidant potentials.
Diphytanyl glycerol ether distributions in sediments of the Orca Basin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pease, T.K.; VanVleet, E.S.; Barre, J.S.
1992-09-01
Archaebacterially produced diphytanyl glycerol ether (DPGE) was examined in core sediments from the Orca Basin, an anoxic hypersaline basin in the northwestern Gulf of Mexico, to observe its spatial variability and potential origin. A differential extraction protocol was employed to quantify the isopranyl glycerol ethers associated with unbound, intermediate-bound, and kerogen-bound lipid fractions. Archaebacterial lipids were evident at all depths for the unbound and intermediate-bound fractions. Concentrations of DPGE ranged from 0.51 to 2.91 [mu]g/g dry sediment at the surface and showed secondary maxima deeper in basin sediments. Intermediate-bound DPGE concentrations exhibited an inverse relationship to unbound DPGE concentrations. Kerogen-boundmore » DPGE concentrations were normally below detection limits. Earlier studies describing the general homogeneity of lipid components within the overlying brine and at the brine/seawater interface suggest that the large-scale sedimentary DPGE variations observed in this study result from spatial and temporal variations in in-situ production by methanogenic or extremely halophilic archaebacteria.« less
NASA Astrophysics Data System (ADS)
Ramani, R.; Alam, S.
2015-06-01
High performance polymer blend of poly(ether ether ketone) (PEEK) and poly(ether imide) (PEI) was examined for their free volume behaviour using positron annihilation lifetime spectroscopy and dynamic mechanical thermal analysis methods. The fractional free volume obtained from PALS shows a negative deviation from linear additivity rule implying good miscibility between PEEK and PEI. The dynamic modulus and loss tangent were obtained for the blends at three different frequencies 1, 10 and 100 Hz at temperatures close to and above their glass transition temperature. Applying Time-Temperature-Superposition (TTS) principle to the DMTA results, master curves were obtained at a reference temperature To and the WLF coefficients c01 and c02 were evaluated. Both the methods give similar results for the dependence of fractional free volume on PEI content in this blend. The results reveal that free volume plays an important role in determining the visco-elastic properties in miscible polymer blends.
[Inhibition effects of Houttuynia cordata Thunb. on Microcystis aeruginosa].
Liu, Lu; Li, Cheng; Xia, Wentong; Yang, Xiaohui; Zhang, Tingting
2014-05-01
To research the inhibitory effect of Houttuynia cordata Thunb. on Microcystis aeruginosa. M. aeruginosat were treated respectively by H. cordata leaching solution or H. cordata extracts. H. cordata leaching solution extracted by water and the H. cordata extracts extracted by organic solvent (acetone, ethyl acetate, petroleum ether and ethanol, respectively). The inhibition ratios were calculated according to the M. aeruginosa densities, and the allelochemicals of the extract that had the best inhibitiory effect on M. aeruginosa were identified by GC-MS analysis. It was proved that leaching solution of H. cordata and four crude extracts had good inhibitory effect on M. aeruginosa. The inhibitory effects of the four crude extracts were the fraction extracted by ethyl acetate, the fraction extracted by ethanol, the fraction extracted by acetone and the fraction extracted by petroleum ether form strong to weak in turn. Then, the allelochemicals of the fraction extracted by ethyl acetate were indentified, mainly including acetonyldimethylcarbinol, 2,2-dimethyl-3-hexanone, 6-chlorohexanoic and 4-cyanophenyl ester. H. cordata has strong inhibitory effect on water-blooming cyanobacteria and the potential to develop into an ecological M. aeruginosa inhibiting agent.
Cretu, Elena; Karonen, Maarit; Salminen, Juha-Pekka; Mircea, Cornelia; Trifan, Adriana; Charalambous, Christiana; Constantinou, Andreas I; Miron, Anca
2013-11-01
A crude hydromethanolic extract from Pinus brutia bark and its fractions (diethyl ether, ethyl acetate, n-butanol, and aqueous fractions) were studied with regard to their phenolic content and antioxidant activities. The total phenolics and proanthocyanidins in each extract were quantified by spectrophotometric methods; the polyphenolic profile was analyzed by RP-HPLC-DAD-ESI-MS. All extracts were tested with regard to their ability to scavenge free radicals (ABTS radical cation, superoxide and hydroxyl radicals), reduce ferric ions, and inhibit 15-lipoxygenase. P. brutia bark extracts had high phenolic contents (303.79±7.34-448.90±1.39 mg/g). Except diethyl ether extract, all other extracts contained proanthocyanidins ranging from 225.79±3.94 to 250.40±1.44 mg/g. Several polyphenols were identified by RP-HPLC-DAD-ESI-MS: taxifolin in diethyl ether extract, a taxifolin-O-hexoside, catechin, procyanidin dimers, and trimers in ethyl acetate extract. Except diethyl ether extract, all other extracts were effective scavengers of superoxide and hydroxyl radicals (EC₅₀=33.5±1.1-54.93±2.85 μg/mL and 0.47±0.06-0.6±0.0 mg/mL, respectively). All extracts had noticeable 15-lipoxygenase inhibitory effects (EC₅₀=22.47±0.75-34.43±2.25 μg/mL). We conclude that P. brutia bark is very promising for the dietary supplements industry due to its high free radical scavenging and 15-lipoxygenase inhibitory effects.
Cryosurgery with pulsed electric fields.
Daniels, Charlotte S; Rubinsky, Boris
2011-01-01
This study explores the hypothesis that combining the minimally invasive surgical techniques of cryosurgery and pulsed electric fields will eliminate some of the major disadvantages of these techniques while retaining their advantages. Cryosurgery, tissue ablation by freezing, is a well-established minimally invasive surgical technique. One disadvantage of cryosurgery concerns the mechanism of cell death; cells at high subzero temperature on the outer rim of the frozen lesion can survive. Pulsed electric fields (PEF) are another minimally invasive surgical technique in which high strength and very rapid electric pulses are delivered across cells to permeabilize the cell membrane for applications such as gene delivery, electrochemotherapy and irreversible electroporation. The very short time scale of the electric pulses is disadvantageous because it does not facilitate real time control over the procedure. We hypothesize that applying the electric pulses during the cryosurgical procedure in such a way that the electric field vector is parallel to the heat flux vector will have the effect of confining the electric fields to the frozen/cold region of tissue, thereby ablating the cells that survive freezing while facilitating controlled use of the PEF in the cold confined region. A finite element analysis of the electric field and heat conduction equations during simultaneous tissue treatment with cryosurgery and PEF (cryosurgery/PEF) was used to study the effect of tissue freezing on electric fields. The study yielded motivating results. Because of decreased electrical conductivity in the frozen/cooled tissue, it experienced temperature induced magnified electric fields in comparison to PEF delivered to the unfrozen tissue control. This suggests that freezing/cooling confines and magnifies the electric fields to those regions; a targeting capability unattainable in traditional PEF. This analysis shows how temperature induced magnified and focused PEFs could be used to ablate cells in the high subzero freezing region of a cryosurgical lesion.
Meneses, Nicolas; Jaeger, Henry; Knorr, Dietrich
2011-10-01
A co-linear pulsed electric field (PEF) treatment chamber was analyzed and optimized considering electrical process conditions, temperature, and retention of heat-sensitive compounds during a continuous PEF treatment of peach juice. The applicability of a jacket heat-exchanger device surrounding the ground electrode was studied in order to provide active cooling and to avoid temperature peaks within the treatment chamber thus reducing the total thermal load to which the product is exposed. Simulation of the PEF process was performed using a finite element method prior to experimental verification. Inactivation of polyphenoloxydase (PPO) and peroxidase (POD) as well as the degradation of ascorbic acid (AA) in peach juice was quantified and used as indirect indicators for the temperature distribution. Peaks of product temperature within the treatment chamber were reduced, that is, from 98 to 75 °C and retention of the indicators PPO, POD, and AA increased by more than 10% after application of the active electrode cooling device. Practical Application: The co-linear PEF treatment chamber is widely used for continuous PEF treatment of liquid products and also suitable for industrial scale application; however, Joule heating in combination with nonuniform electric field distribution may lead to unwanted thermal effects. The proposed design showed potential to reduce the thermal load, to which the food is exposed, allowing the retention of heat-sensitive components. The design is applicable at laboratory or industrial scale to perform PEF trials avoiding temperature peaks, which is also the basis for obtaining inactivation kinetic models with minimized thermal impact on the kinetic variables. © 2011 Institute of Food Technologists®
NASA Astrophysics Data System (ADS)
Wei, Kai; Li, Wei; Gao, Shan; Ji, Bin; Zang, Yating; Su, Bo; Wang, Kaile; Yao, Maosheng; Zhang, Jue; Wang, Jinglin
2016-01-01
Ricin is one of the most toxic and easily produced plant protein toxin extracted from the castor oil plant, and it has been classified as a chemical warfare agent. Here, nanosecond pulsed electric fields (nsPEFs) at 30 kV/cm (pulse durations: 10 ns, 100 ns, and 300 ns) were applied to inactivating ricin up to 4.2 μg/mL. To investigate the efficacy, cells and mice were tested against the ricin treated by the nsPEFs via direct intraperitoneal injection and inhalation exposure. Results showed that nsPEFs treatments can effectively reduce the toxicity of the ricin. Without the nsPEFs treatment, 100% of mice were killed upon the 4 μg ricin injection on the first day, however 40% of the mice survived the ricin treated by the nsPEFs. Compared to injection, inhalation exposure even with higher ricin dose required longer time to observe mice fatality. Pathological observations revealed damages to heart, lung, kidney, and stomach after the ricin exposure, more pronounced for lung and kidney including severe bleeding. Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) and circular dichroism (CD) analyses revealed that although the primary structure of ricin was not altered, its secondary structures (beta-sheet and beta-turn) underwent transition upon the nsPEFs treatment.
Wei, Kai; Li, Wei; Gao, Shan; Ji, Bin; Zang, Yating; Su, Bo; Wang, Kaile; Yao, Maosheng; Zhang, Jue; Wang, Jinglin
2016-01-01
Ricin is one of the most toxic and easily produced plant protein toxin extracted from the castor oil plant, and it has been classified as a chemical warfare agent. Here, nanosecond pulsed electric fields (nsPEFs) at 30 kV/cm (pulse durations: 10 ns, 100 ns, and 300 ns) were applied to inactivating ricin up to 4.2 μg/mL. To investigate the efficacy, cells and mice were tested against the ricin treated by the nsPEFs via direct intraperitoneal injection and inhalation exposure. Results showed that nsPEFs treatments can effectively reduce the toxicity of the ricin. Without the nsPEFs treatment, 100% of mice were killed upon the 4 μg ricin injection on the first day, however 40% of the mice survived the ricin treated by the nsPEFs. Compared to injection, inhalation exposure even with higher ricin dose required longer time to observe mice fatality. Pathological observations revealed damages to heart, lung, kidney, and stomach after the ricin exposure, more pronounced for lung and kidney including severe bleeding. Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) and circular dichroism (CD) analyses revealed that although the primary structure of ricin was not altered, its secondary structures (beta-sheet and beta-turn) underwent transition upon the nsPEFs treatment. PMID:26728251
Nanosecond pulsed electric fields have differential effects on cells in the S-phase.
Hall, Emily H; Schoenbach, Karl H; Beebe, Stephen J
2007-03-01
Nanosecond pulsed electric fields (nsPEFs) are a type of nonthermal, nonionizing radiation that exhibit intense electric fields with high power, but low energy. NsPEFs extend conventional electroporation (EP) to affect intracellular structures and functions and depending on the intensity, can induce lethal and nonlethal cell signaling. In this study, HCT116 human colon carcinoma cells were synchronized to the S-phase or remained unsynchronized, exposed to electric fields of 60 kV/cm with either 60-ns or 300-ns durations, and analyzed for apoptosis and proliferative markers. Several nsPEF structural and functional targets were identified. Unlike unsynchronized cells, S-phase cells under limiting conditions exhibited greater membrane integrity and caspase activation and maintained cytoskeletal structure. Regardless of synchronization, cells exposed to nsPEFs under these conditions primarily survived, but exhibited some turnover and delayed proliferation in cell populations, as well as reversible increases in phosphatidylserine externalization, membrane integrity, and nuclei size. These results show that nsPEFs can act as a nonligand agonist to modulate plasma membrane (PM) and intracellular structures and functions, as well as differentially affect cells in the S-phase, but without effect on cell survival. Furthermore, nsPEF effects on the nucleus and cytoskeleton may provide synergistic therapeutic actions with other agents, such as ionizing radiation or chemotherapeutics that affect these same structures.
Pakhomov, Andrei G; Xiao, Shu; Pakhomova, Olga N; Semenov, Iurii; Kuipers, Marjorie A; Ibey, Bennett L
2014-12-01
Disruption of the actin cytoskeleton structures was reported as one of the characteristic effects of nanosecond-duration pulsed electric field (nsPEF) in both mammalian and plant cells. We utilized CHO cells that expressed the monomeric fluorescent protein (mApple) tagged to actin to test if nsPEF modifies the cell actin directly or as a consequence of cell membrane permeabilization. A train of four 600-ns pulses at 19.2 kV/cm (2 Hz) caused immediate cell membrane poration manifested by YO-PRO-1 dye uptake, gradual cell rounding and swelling. Concurrently, bright actin features were replaced by dimmer and uniform fluorescence of diffuse actin. To block the nsPEF-induced swelling, the bath buffer was isoosmotically supplemented with an electropore-impermeable solute (sucrose). A similar addition of a smaller, electropore-permeable solute (adonitol) served as a control. We demonstrated that sucrose efficiently blocked disassembly of actin features by nsPEF, whereas adonitol did not. Sucrose also attenuated bleaching of mApple-tagged actin in nsPEF-treated cells (as integrated over the cell volume), although did not fully prevent it. We conclude that disintegration of the actin cytoskeleton was a result of cell swelling, which, in turn, was caused by cell permeabilization by nsPEF and transmembrane diffusion of solutes which led to the osmotic imbalance. Copyright © 2014 Elsevier B.V. All rights reserved.
Derivative-free generation and interpolation of convex Pareto optimal IMRT plans
NASA Astrophysics Data System (ADS)
Hoffmann, Aswin L.; Siem, Alex Y. D.; den Hertog, Dick; Kaanders, Johannes H. A. M.; Huizenga, Henk
2006-12-01
In inverse treatment planning for intensity-modulated radiation therapy (IMRT), beamlet intensity levels in fluence maps of high-energy photon beams are optimized. Treatment plan evaluation criteria are used as objective functions to steer the optimization process. Fluence map optimization can be considered a multi-objective optimization problem, for which a set of Pareto optimal solutions exists: the Pareto efficient frontier (PEF). In this paper, a constrained optimization method is pursued to iteratively estimate the PEF up to some predefined error. We use the property that the PEF is convex for a convex optimization problem to construct piecewise-linear upper and lower bounds to approximate the PEF from a small initial set of Pareto optimal plans. A derivative-free Sandwich algorithm is presented in which these bounds are used with three strategies to determine the location of the next Pareto optimal solution such that the uncertainty in the estimated PEF is maximally reduced. We show that an intelligent initial solution for a new Pareto optimal plan can be obtained by interpolation of fluence maps from neighbouring Pareto optimal plans. The method has been applied to a simplified clinical test case using two convex objective functions to map the trade-off between tumour dose heterogeneity and critical organ sparing. All three strategies produce representative estimates of the PEF. The new algorithm is particularly suitable for dynamic generation of Pareto optimal plans in interactive treatment planning.
Shiraishi, Eri; Hosseini, Hamid; Kang, Dong K; Kitano, Takeshi; Akiyama, Hidenori
2013-01-01
Application of nanosecond pulsed electric fields (nsPEFs) has attracted rising attention in various scientific fields including medical, pharmacological, and biological sciences, although its effects and molecular mechanisms leading to the effects remain poorly understood. Here, we show that a single, high-intensity (10-30 kV/cm), 60-ns PEF exposure affects gene expression and impairs development of eyes and germ cells in medaka (Oryzias latipes). Exposure of early blastula stage embryos to nsPEF down-regulated the expression of several transcription factors which are essential for eye development, causing abnormal eye formation. Moreover, the majority of the exposed genetic female embryos showed a fewer number of germ cells similar to that of the control (unexposed) genetic male at 9 days post-fertilization (dpf). However, all-trans retinoic acid (atRA) treatment following the exposure rescued proliferation of germ cells and resumption of normal eye development, suggesting that the phenotypes induced by nsPEF are caused by a decrease of retinoic acid levels. These results confirm that nsPEFs induce novel effects during embryogenesis in medaka.
Advantages and disadvantages of pinless external fixation.
Thomas, S R; Giele, H; Simpson, A H
2000-12-01
The AO pinless external fixator (PEF) uses trocar tipped clamps to grip the outer tibial cortex rather than pins to transfix it. Its main advantage is to avoid further contamination of the medullary canal in open tibial fractures where a nail may subsequently be used. We tested the anatomical safety of this device and its effect on plastic surgical procedures compared with a standard unilateral external fixator (UEF).The PEF and UEF were placed on two amputated limbs which were then dissected. Structures at risk were traced on ten cadaver limbs. We found that important anatomical structures were endangered by the PEF and that safe zones could not always be defined. The UEF avoided these structures. Plastic surgical approaches were made more difficult by the PEF which imposed limitations on local flap design and endangered the arterial perforators which supply them. We conclude that safety is compromised by the PEF because margins for error are small. It poses additional problems in soft tissue reconstruction and highlights the need for co-operation between plastic surgical and orthopaedic teams in choice of fixation device.
Catalytic distillation process
Smith, Jr., Lawrence A.
1982-01-01
A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.
Catalytic distillation process
Smith, L.A. Jr.
1982-06-22
A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.
Anti-fertility effects of different fractions of Anethum graveolens L. extracts on female rats.
Malihezaman, Monsefi; Mojaba, Masoudi; Elham, Hosseini; Farnaz, Gramifar; Ramin, Miri
2012-01-01
Our previous studies showed the effects of aqueous and ethanol extracts of Anethum graveolens L. (dill) on female infertility. In the present study we investigated whether different fractions of this herb extract can cause infertility in rats. Female rats were divided into the control groups, the groups receiving either a low (0.5 g/kg)) or a high dose (5g/kg) of water, N-butanol, chloroform and ether fractions of the aqueous plant extract, and the groups receiving either a low (0.045 g/kg) or a high dose (0.45 g/kg) of the same fractions of ethanol extract. The mentioned doses were gavaged in 1mL for 10 days. Vaginal smears were prepared daily. Estradiol and progesterone levels were measured. The left oviduct and ovary were removed, their tissue subsequently being prepared in form of histology slides and stained using haematoxylin-eosin and Masson's trichrome. Female rats assigned to each group were mated with males; after that, crown-rump lengths and weights of newborn rats were measured. Results showed that each fraction produced some changes such as hormonal level reduction (chloroform fraction), diestrus phase prolongation and infertility (water fraction), and increase in pregnancy duration (chloroform and ether fractions). We concluded that each fraction comprises only some of the mentioned components and therefore recommended the usage of crude extract, especially the aqueous one, in case infertility aims to be induced.
Feung, Chao-Shieung; Hamilton, Robert H.; Witham, Francis H.; Mumma, Ralph O.
1972-01-01
Soybean (Glycine max L.) cotyledon callus grown on radioactive 2,4-dichlorophenoxyacetic acid (2,4-D-1-14C) as an auxin produced 2,4-D metabolites, which qualitatively and quantitatively changed with time. Water soluble fractions from the tissue exhibited a steady increase in radioactivity during the course of 24 days. Following β-glucosidase treatment, at least eight aglycones were obtained from the water soluble fraction of the tissue after 8 days. The metabolite, 4-hydroxy-2,5-dichlorophenoxyacetic acid was the most abundant aglycone during the entire 32 day growth period while 4-hydroxy-2,3-dichlorophenoxyacetic acid was detected as a minor metabolite. Radioactivity in the ether soluble acidic fractions reached a maximum of 82% of the total in the tissue after 2 days. The level then decreased to 44% by the end of 24 days. A total of seven ether soluble components were detected. In addition to 2,4-D glutamic acid, which was detected in high amounts after 24 hours, 2,4-D aspartic acid was found to be the most abundant ether soluble metabolite after longer time periods. Mass spectral data and a fragmentation pattern are presented for 2,4-D aspartic acid. PMID:16658138
Hepatoprotective activity of Trichilia roka on carbon tetrachloride-induced liver damage in rats.
Germanò, M P; D'Angelo, V; Sanogo, R; Morabito, A; Pergolizzi, S; De Pasquale, R
2001-11-01
Trichilia roka Chiov. (Meliaceae) is a tree widely distributed in tropical Africa. It has been used in Mali folk medicine for the treatment of various illnesses. A decoction of the roots is taken as a remedy for colds and pneumonia, and it is used as a diuretic and in hepatic disorders. We have evaluated the hepatoprotective effects of a decoction of Trichilia roka root on CCl4-induced acute liver damage in rats. Treatment with the decoction showed a significant protective action made evident by its effect on the levels of glutamate oxalacetate transaminase and glutamate pyruvate transaminase in the serum, on the protein content and lipid peroxidation levels in the liver homogenate. Histopathological changes produced by CCl4, such as necrosis, fatty change, ballooning degeneration and inflammatory infiltration of lymphocytes around the central veins, were clearly recovered by the treatment with Trichilia root decoction. On fractionating this extract into diethyl ether-soluble and water-soluble fractions, the activity was retained in the diethyl ether-soluble fraction. Moreover, the administration of decoction prevented a preferential deposition of collagen around the sinusoidal cell layer, which is responsible for the perisinusoidal fibrosis in the early stage of CCl4 damage. This study showed that treatment with Trichilia roka extracts or silymarin (as reference) appeared to enhance the recovery from CCl4-induced hepatotoxicity. The hepatoprotective properties of Trichilia roka may be correlated to polyphenol content of the decoction and its diethyl ether-soluble fraction.
Kılıc, Hatice; Kanbay, Asiye; Karalezlı, Ayşegul; Babaoglu, Elif; Hasanoglu, H Canan; Erel, Ozcan; Ates, Can
2018-01-01
To investigate the relationship between serum values of magnesium and the parameters of the pulmonary function tests (PFT) in patients with chronic asthma. This study recruited 50 patients with chronic stable asthma and 40 healthy individuals as a control group. Data on age, sex, severity of asthma, PFT, and details of drug therapy were obtained from each group. Serum magnesium, potassium, phosphorus, calcium, and sodium levels were also measured. To evaluate differences between groups, the Student t test or Mann-Whitney U test was performed for continuous variables, and the χ2 test for categorical variables. In the asthma group, 10% (n = 9) of the patients had hypomagnesemia and 5.5% (n = 5) had hypophosphatemia. Patients with asthma were divided into two groups: the hypomagnesemic group (n = 9) and the normomagnesemic group (n = 41). Forced expiratory volume in 1 s (FEV1), FEV1%, peak expiratory flow (PEF), and PEF% were lower in the hypomagnesemic group than in the normomagnesemic group (p = 0.02). Multiple logistic regression analysis revealed a statistically significant association between hypomagnesemia and PFT in the hypomagnesemic asthmatic group. The correlations of age with FEV1, FEV1%, PEF, and PEF% were as follows: p = 0.00, r = 0.29; p = 0.00, r = 0.43; p = 0.03, r = 0.22; p = 0.00, r = 0.38; and p = 0.03, r = 0.22, respectively. The correlation of serum magnesium levels with PFT (FEV1, FEV1%, PEF, PEF%) were as follows: p = 0.001, r = 0.29; p = 0.001, r = 0.43; p = 0.03, r = 0.22; and p = 0.001, r = 0.38, respectively. The other electrolytes were within the normal range in both groups. In this study, hypomagnesemia and hypophosphatemia were found to be the most common electrolyte abnormalities in patients with chronic stable asthma. FEV1, FEV1%, PEF, and PEF% were significantly lower in asthmatic patients with hypomagnesemia compared to asthmatic patients with normomagnesemia. ©2018 The Author(s). Published by S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Semelsberger, Troy A.; Borup, Rodney L.
The production of a hydrogen-rich fuel-cell feed by dimethyl ether (DME) steam reforming was investigated using calculations of thermodynamic equilibrium as a function of steam-to-carbon ratio (0.00-4.00), temperature (100-600 °C), pressure (1-5 atm), and product species. Species considered were acetone, acetylene, carbon dioxide, carbon monoxide, dimethyl ether, ethane, ethanol, ethylene, formaldehyde, formic acid, hydrogen, isopropanol, methane, methanol, methyl-ethyl ether, n-propanol and water. Thermodynamic equilibrium calculations of DME steam reforming indicate complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide at temperatures greater than 200 °C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure ( P = 1 atm). Increasing the operating pressure shifts the equilibrium toward the reactants; increasing the pressure from 1 to 5 atm decreases the conversion of dimethyl ether from 99.5 to 76.2%. The trend of thermodynamically stable products in decreasing mole fraction is methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol-formaldehyde, formic acid, and acetylene were not observed. Based on the equilibrium calculations, the optimal processing conditions for dimethyl ether steam reforming occur at a steam-to-carbon ratio of 1.50, a pressure of 1 atm, and a temperature of 200 °C. These thermodynamic equilibrium calculations show dimethyl ether processed with steam will produce hydrogen-rich fuel-cell feeds—with hydrogen concentrations exceeding 70%. The conversion of dimethyl ether via hydrolysis (considering methanol as the only product) is limited by thermodynamic equilibrium. Equilibrium conversion increases with temperature and steam-to-carbon ratio. A maximum dimethyl ether conversion of 62% is achieved at a steam-to-carbon ratio of 5.00 and a processing temperature of 600 °C.
Effect of pulsed electric fields upon accumulation of zinc in Saccharomyces cerevisiae.
Pankiewicz, Urszula; Jamroz, Jerzy
2011-06-01
Cultures of Saccharomyces cerevisiae were treated with pulsed electric fields to improve accumulation of zinc in the biomass. Under optimized conditions, that is, on 15 min exposure of the 20 h grown culture to PEFs of 1500 V and 10 microns pulse width, accumulation of zinc in the yeast biomass reached a maximum of 15.57 mg/g d.m. Under optimum zinc concentration (100 microgram/ml nutrient medium), its accumulation in the cells was higher by 63% in comparison with the control (without PEFs). That accumulation significantly correlated against zinc concentration in the medium. Neither multiple exposure of the cultures to PEFs nor intermittent supplementation of the cultures with zinc increased the zinc accumulation. The intermittent supplementation of the cultures with zinc and multiple exposures on PEFs could even reduce the accumulation efficiency, respectively, by 57% and 47%.
Temperature Modulation of Electric Fields in Biological Matter
Daniels, Charlotte S.; Rubinsky, Boris
2011-01-01
Pulsed electric fields (PEF) have become an important minimally invasive surgical technology for various applications including genetic engineering, electrochemotherapy and tissue ablation. This study explores the hypothesis that temperature dependent electrical parameters of tissue can be used to modulate the outcome of PEF protocols, providing a new means for controlling and optimizing this minimally invasive surgical procedure. This study investigates two different applications of cooling temperatures applied during PEF. The first case utilizes an electrode which simultaneously delivers pulsed electric fields and cooling temperatures. The subsequent results demonstrate that changes in electrical properties due to temperature produced by this configuration can substantially magnify and confine the electric fields in the cooled regions while almost eliminating electric fields in surrounding regions. This method can be used to increase precision in the PEF procedure, and eliminate muscle contractions and damage to adjacent tissues. The second configuration considered introduces a third probe that is not electrically active and only applies cooling boundary conditions. This second study demonstrates that in this probe configuration the temperature induced changes in electrical properties of tissue substantially reduce the electric fields in the cooled regions. This novel treatment can potentially be used to protect sensitive tissues from the effect of the PEF. Perhaps the most important conclusion of this investigation is that temperature is a powerful and accessible mechanism to modulate and control electric fields in biological tissues and can therefore be used to optimize and control PEF treatments. PMID:21695144
Liu, Ya-Fei; Oey, Indrawati; Bremer, Phil; Carne, Alan; Silcock, Pat
2017-01-01
The effect of either pulsed electric fields (PEF) or thermal processing on protein aggregation of ovomucin-depleted egg white (OdEW) solutions at different pH was assessed by solution turbidity and SDS-PAGE. Heating to 60°C for 10min caused marked protein aggregation of OdEW at pH5, 7, and 9. At constant electric field strength (E=1.4-1.8kV/cm), PEF processing under high specific energy input (W spec =260-700kJ/kg) induced some protein aggregation at pH5 and 7, but not at either pH4 or 9. Similar effects of pH on protein aggregation were observed upon PEF processing at varied E (from 0.7 to 1.7kV/cm) but with constant W spec (713kJ/kg). Analysis by SDS-PAGE revealed that proteins in the OdEW solution at pH5 were most susceptible to both PEF- and heat-induced protein aggregation and lysozyme was only involved in the formation of insoluble aggregates under PEF. The present study shows that PEF treatment has considerable potential for minimizing protein aggregation in the processing of heat-labile egg white proteins. Retaining the OdEW proteins in solution during processing has potential industry application, for example, protein fortification of drinks with OdEW, where minimizing solution turbidity would be advantageous. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Riera, Marc; Mardirossian, Narbe; Bajaj, Pushp; Götz, Andreas W.; Paesani, Francesco
2017-10-01
This study presents the extension of the MB-nrg (Many-Body energy) theoretical/computational framework of transferable potential energy functions (PEFs) for molecular simulations of alkali metal ion-water systems. The MB-nrg PEFs are built upon the many-body expansion of the total energy and include the explicit treatment of one-body, two-body, and three-body interactions, with all higher-order contributions described by classical induction. This study focuses on the MB-nrg two-body terms describing the full-dimensional potential energy surfaces of the M+(H2O) dimers, where M+ = Li+, Na+, K+, Rb+, and Cs+. The MB-nrg PEFs are derived entirely from "first principles" calculations carried out at the explicitly correlated coupled-cluster level including single, double, and perturbative triple excitations [CCSD(T)-F12b] for Li+ and Na+ and at the CCSD(T) level for K+, Rb+, and Cs+. The accuracy of the MB-nrg PEFs is systematically assessed through an extensive analysis of interaction energies, structures, and harmonic frequencies for all five M+(H2O) dimers. In all cases, the MB-nrg PEFs are shown to be superior to both polarizable force fields and ab initio models based on density functional theory. As previously demonstrated for halide-water dimers, the MB-nrg PEFs achieve higher accuracy by correctly describing short-range quantum-mechanical effects associated with electron density overlap as well as long-range electrostatic many-body interactions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yin, Shengyong; Chen, Xinhua; Xie, Haiyang
Previous studies showed nanosecond pulsed electric field (nsPEF) can ablate solid tumors including hepatocellular carcinoma (HCC) but its effect on cell membrane is not fully understood. We hypothesized nsPEF disrupt the microdomains on outer-cellular membrane with direct mechanical force and as a result the plasma membrane permeability increases to facilitate the small molecule intake. Three HCC cells were pulsed one pulse per minute, an interval longer than nanopore resealing time. The cationized ferritin was used to mark up the electronegative microdomains, propidium iodide (PI) for membrane permeabilization, energy dispersive X-ray spectroscopy (EDS) for the negative cell surface charge and cisplatinmore » for inner-cellular cytotoxicity. We demonstrated that the ferritin marked-microdomain and negative cell surface charge were disrupted by nsPEF caused-mechanical force. The cell uptake of propidium and cytotoxicity of DNA-targeted cisplatin increased with a dose effect. Cisplatin gains its maximum inner-cellular cytotoxicity when combining with nsPEF stimulation. We conclude that nsPEF disrupt the microdomains on the outer cellular membrane directly and increase the membrane permeabilization for PI and cisplatin. The microdomain disruption and membrane infiltration changes are caused by the mechanical force from the changes of negative cell surface charge.« less
Optimising the inactivation of grape juice spoilage organisms by pulse electric fields.
Marsellés-Fontanet, A Robert; Puig, Anna; Olmos, Paola; Mínguez-Sanz, Santiago; Martín-Belloso, Olga
2009-04-15
The effect of some pulsed electric field (PEF) processing parameters (electric field strength, pulse frequency and treatment time), on a mixture of microorganisms (Kloeckera apiculata, Saccharomyces cerevisiae, Lactobacillus plantarum, Lactobacillus hilgardii and Gluconobacter oxydans) typically present in grape juice and wine were evaluated. An experimental design based on response surface methodology (RSM) was used and results were also compared with those of a factorially designed experiment. The relationship between the levels of inactivation of microorganisms and the energy applied to the grape juice was analysed. Yeast and bacteria were inactivated by the PEF treatments, with reductions that ranged from 2.24 to 3.94 log units. All PEF parameters affected microbial inactivation. Optimal inactivation of the mixture of spoilage microorganisms was predicted by the RSM models at 35.0 kV cm(-1) with 303 Hz pulse width for 1 ms. Inactivation was greater for yeasts than for bacteria, as was predicted by the RSM. The maximum efficacy of the PEF treatment for inactivation of microorganisms in grape juice was observed around 1500 MJ L(-1) for all the microorganisms investigated. The RSM could be used in the fruit juice industry to optimise the inactivation of spoilage microorganisms by PEF.
Reflex cough PEF as a predictor of successful extubation in neurological patients*
Kutchak, Fernanda Machado; Debesaitys, Andressa Maciel; Rieder, Marcelo de Mello; Meneguzzi, Carla; Skueresky, Amanda Soares; Alberto, Luiz; Bianchin, Marino Muxfeldt
2015-01-01
Abstract Objective: To evaluate the use of reflex cough PEF as a predictor of successful extubation in neurological patients who were candidates for weaning from mechanical ventilation. Methods: This was a cross-sectional study of 135 patients receiving mechanical ventilation for more than 24 h in the ICU of Cristo Redentor Hospital, in the city of Porto Alegre, Brazil. Reflex cough PEF, the rapid shallow breathing index, MIP, and MEP were measured, as were ventilatory, hemodynamic, and clinical parameters. Results: The mean age of the patients was 47.8 ± 17 years. The extubation failure rate was 33.3%. A reflex cough PEF of < 80 L/min showed a relative risk of 3.6 (95% CI: 2.0-6.7), and the final Glasgow Coma Scale score showed a relative risk of 0.64 (95% CI: 0.51-0.83). For every 1-point increase in a Glasgow Coma Scale score of 8, there was a 36% reduction in the risk of extubation failure. Conclusions: Reflex cough PEF and the Glasgow Coma Scale score are independent predictors of extubation failure in neurological patients admitted to the ICU. PMID:26398756
Lin, Songyi; Liang, Rong; Li, Xingfang; Xing, Jie; Yuan, Yuan
2016-12-15
Recently, high-intensity pulsed electric field (PEF) has successfully used in improvement of antioxidant activity. Ser-His-Cys-Met-Asn (SHCMN) obtained from soybean protein was chosen to investigate the phenomenon of antioxidant activity improvement. Effects of PEF treatment on antioxidant activity of SHCMN were evaluated by DPPH radical inhibition. Nuclear magnetic resonance (NMR), mid-infrared (MIR), circular dichroism (CD) were used to analyze structures of SHCMN. Two-factor-at-a-time results show that DPPH radical inhibition of SHCMN is significantly (P<0.05) increased to 94.35±0.03% at conditions of electric field intensity of 5kV/cm, pulse frequency of 2400Hz, and retention time of 2h. In addition, MIR and NMR spectra show that the basic structure of peptides SHCMN is stable by PEF treatment. But the secondary structures (α-helix, β-turn, and random coil) can be affected and zeta potential of PEF-treated SHCNM was reduced to 0.59±0.03mV. The antioxidant activity improvement of SHCMN might result from the changes of secondary structures and zeta potential. Copyright © 2016 Elsevier Ltd. All rights reserved.
Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure.
Thompson, Gary L; Roth, Caleb C; Kuipers, Marjorie A; Tolstykh, Gleb P; Beier, Hope T; Ibey, Bennett L
2016-01-29
Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus - histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. Copyright © 2015 Elsevier Inc. All rights reserved.
Suwandy, Via; Carne, Alan; van de Ven, Remy; Bekhit, Alaa El-Din A; Hopkins, David L
2015-02-01
The effects of pulsed electric field (PEF) and ageing (3, 7, 14 and 21 days) on the shear force, protein profile, and post-mortem proteolysis of beef loins (M. Longissimus lumborum, LL) and topsides (M. Semimembranosus, SM) were investigated using a range of pulsed electric field treatments [voltages (5 and 10 kV) and frequencies (20, 50, and 90 Hz)]. PEF treatment decreased the shear force of beef LL and SM muscles by up to 19%. The reduction in the shear force in the LL was not affected by the treatment intensity whereas the reduction in the SM was dependent on PEF frequency. PEF treated beef loins showed increased proteolysis, both early post-mortem and during subsequent post-mortem storage reflected by increased degradation of troponin-T and desmin. The most prominent troponin-T degradation was found in samples treated with 5 kV-90 Hz, 10 kV-20 Hz at day 3 and day 7 post-treatment in addition to 10 kV-50 Hz in subsequent post-treatment times. The degradation of desmin in PEF treated beef loins increased with ageing time.
Fardin, K M; Young, M C M
2015-07-01
There is significant interest in research to develop plant extracts with fungicidal activities that are less harmful to the environment and human health than synthetic fungicides. This study aimed to evaluate the antifungal activity of the extracts of Avicennia schaueriana against Colletotrichum and Cladosporium species and to identify the compounds responsible for the activity. Leaves and stems of A. schaueriana were extracted with ethanol and partitioned with petroleum ether, chloroform and ethyl acetate. The antifungal activity of such extracts was tested by bioautography against Cladosporium sphaerospermum, Cladosporium cladosporioides and Colletotrichum lagenarium. Ethanolic extracts, petroleum ether and chloroform fractions of stems had the highest antifungal activity with several active bands (Rf = 0·72 and Rf = 0·55). In the agar dilution assay, ethanolic extract, petroleum ether and chloroform fractions of stems were the most efficacious, presenting 85, 62 and 63% growth inhibition of Colletotrichum gloeopsporioides and minimum inhibitory concentration values between 1 and 1·5 mg ml(-1) , respectively. Analysis carried out using gas chromatography coupled to a mass spectrometry of petroleum ether and chloroform fractions allowed the identification of fatty acids methyl esters, lupeol and naphthoquinones such as lapachol, α-lapachone, naphtho[2,3-b]furan-4,9-dione, 2-isopropyl- and avicenol-C. We may infer that the antifungal activity of A. schaueriana is due to the abundance of these compounds. This study shows that Avicennia schaueriana extracts have a high potential for the growth inhibition of Colletotrichum and Cladosporium ssp. and will provide a starting point for discovering new natural products with antifungal activity. Their development is of particular interest to organic production systems where synthetic fungicides cannot be used. © 2015 The Society for Applied Microbiology.
Platz, Elke; Jhund, Pardeep S; Campbell, Ross T; McMurray, John J
2015-09-01
Pulmonary oedema is a common and important finding in acute heart failure (AHF). We conducted a systematic review to describe the methods used to assess pulmonary oedema in recent randomized AHF trials and report its prevalence in these trials. Of 23 AHF trials published between 2002 and 2013, six were excluded because they were very small or not randomized, or missing full-length publications. Of the remaining 17 (n = 200-7141) trials, six enrolled patients with HF and reduced ejection fraction (HF-REF) and 11, patients with both HF-REF and HF with preserved ejection fraction (HF-PEF). Pulmonary oedema was an essential inclusion criterion, in most trials, based upon findings on physical examination ('rales'), radiographic criteria ('signs of congestion'), or both. The prevalence of pulmonary oedema in HF-REF trials ranged from 75% to 83% and in combined HF-REF and HF-PEF trials from 51% to 100%. Five trials did not report the prevalence or extent of pulmonary oedema assessed by either clinical examination or chest x-ray. Improvement of pulmonary congestion with treatment was inconsistently reported and commonly grouped with other signs of congestion into a score. One trial suggested that patients with rales over >2/3 of the lung fields on admission were at higher risk of adverse outcomes than those without. Although pulmonary oedema is a common finding in AHF, represents a therapeutic target, and may be of prognostic importance, recent trials used inconsistent criteria to define it, and did not consistently report its severity at baseline or its response to treatment. Consistent and ideally quantitative, methods for the assessment of pulmonary oedema in AHF trials are needed. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.
Cationic Peptide Exposure Enhances Pulsed-Electric-Field-Mediated Membrane Disruption
Kennedy, Stephen M.; Aiken, Erik J.; Beres, Kaytlyn A.; Hahn, Adam R.; Kamin, Samantha J.; Hagness, Susan C.; Booske, John H.; Murphy, William L.
2014-01-01
Background The use of pulsed electric fields (PEFs) to irreversibly electroporate cells is a promising approach for destroying undesirable cells. This approach may gain enhanced applicability if the intensity of the PEF required to electrically disrupt cell membranes can be reduced via exposure to a molecular deliverable. This will be particularly impactful if that reduced PEF minimally influences cells that are not exposed to the deliverable. We hypothesized that the introduction of charged molecules to the cell surfaces would create regions of enhanced transmembrane electric potential in the vicinity of each charged molecule, thereby lowering the PEF intensity required to disrupt the plasma membranes. This study will therefore examine if exposure to cationic peptides can enhance a PEF’s ability to disrupt plasma membranes. Methodology/Principal Findings We exposed leukemia cells to 40 μs PEFs in media containing varying concentrations of a cationic peptide, polyarginine. We observed the internalization of a membrane integrity indicator, propidium iodide (PI), in real time. Based on an individual cell’s PI fluorescence versus time signature, we were able to determine the relative degree of membrane disruption. When using 1–2 kV/cm, exposure to >50 μg/ml of polyarginine resulted in immediate and high levels of PI uptake, indicating severe membrane disruption, whereas in the absence of peptide, cells predominantly exhibited signatures indicative of no membrane disruption. Additionally, PI entered cells through the anode-facing membrane when exposed to cationic peptide, which was theoretically expected. Conclusions/Significance Exposure to cationic peptides reduced the PEF intensity required to induce rapid and irreversible membrane disruption. Critically, peptide exposure reduced the PEF intensities required to elicit irreversible membrane disruption at normally sub-electroporation intensities. We believe that these cationic peptides, when coupled with current advancements in cell targeting techniques will be useful tools in applications where targeted destruction of unwanted cell populations is desired. PMID:24671150
Cryosurgery with Pulsed Electric Fields
Daniels, Charlotte S.; Rubinsky, Boris
2011-01-01
This study explores the hypothesis that combining the minimally invasive surgical techniques of cryosurgery and pulsed electric fields will eliminate some of the major disadvantages of these techniques while retaining their advantages. Cryosurgery, tissue ablation by freezing, is a well-established minimally invasive surgical technique. One disadvantage of cryosurgery concerns the mechanism of cell death; cells at high subzero temperature on the outer rim of the frozen lesion can survive. Pulsed electric fields (PEF) are another minimally invasive surgical technique in which high strength and very rapid electric pulses are delivered across cells to permeabilize the cell membrane for applications such as gene delivery, electrochemotherapy and irreversible electroporation. The very short time scale of the electric pulses is disadvantageous because it does not facilitate real time control over the procedure. We hypothesize that applying the electric pulses during the cryosurgical procedure in such a way that the electric field vector is parallel to the heat flux vector will have the effect of confining the electric fields to the frozen/cold region of tissue, thereby ablating the cells that survive freezing while facilitating controlled use of the PEF in the cold confined region. A finite element analysis of the electric field and heat conduction equations during simultaneous tissue treatment with cryosurgery and PEF (cryosurgery/PEF) was used to study the effect of tissue freezing on electric fields. The study yielded motivating results. Because of decreased electrical conductivity in the frozen/cooled tissue, it experienced temperature induced magnified electric fields in comparison to PEF delivered to the unfrozen tissue control. This suggests that freezing/cooling confines and magnifies the electric fields to those regions; a targeting capability unattainable in traditional PEF. This analysis shows how temperature induced magnified and focused PEFs could be used to ablate cells in the high subzero freezing region of a cryosurgical lesion. PMID:22087224
Dynamic effects and applications for nanosecond pulsed electric fields in cells and tissues
NASA Astrophysics Data System (ADS)
Beebe, Stephen J.; Blackmore, Peter F.; Hall, Emily; White, Jody A.; Willis, Lauren K.; Fauntleroy, Laura; Kolb, Juergen F.; Schoenbach, Karl H.
2005-04-01
Nanosecond, high intensity pulsed electric fields [nsPEFs] that are below the plasma membrane [PM] charging time constant have decreasing effects on the PM and increasing effects on intracellular structures and functions as the pulse duration decreases. When human cell suspensions were exposed to nsPEFs where the electric fields were sufficiently intense [10-300ns, <=300 kV/cm.], apoptosis signaling pathways could be activated in several cell models. Multiple apoptosis markers were observed in Jurkat, HL-60, 3T3L1-preadipocytes, and isolated rat adipocytes including decreased cell size and number, caspase activation, DNA fragmentation, and/or cytochrome c release into the cytoplasm. Phosphatidylserine externalization was observed as a biological response to nsPEFs in 3T3-L1 preadipocytes and p53-wildtype and -null human colon carcinoma cells. B10.2 mouse fibrosarcoma tumors that were exposed to nsPEFs ex vivo and in vivo exhibited DNA fragmentation, elevated caspase activity, and reduced size and weight compared to contralateral sham-treated control tumors. When nsPEF conditions were below thresholds for apoptosis and classical PM electroporation, non-apoptotic responses were observed similar to those initiated through PM purinergic receptors in HL-60 cells and thrombin in human platelets. These included Ca2+ mobilization from intracellular stores [endoplasmic reticulum] and subsequently through store-operated Ca2+ channels in the PM. In addition, platelet activation measured as aggregation responses were observed in human platelets. Finally, when nsPEF conditions followed classical electroporation-mediated transfection, the expression intensity and number of GFP-expressing cells were enhanced above cells exposed to electroporation conditions alone. These studies demonstrate that application of nsPEFs to cells or tissues can modulate cell-signaling mechanisms with possible applications as a new basic science tool, cancer treatment, wound healing, and gene therapy.
Walkling-Ribeiro, M; Noci, F; Cronin, D A; Lyng, J G; Morgan, D J
2008-10-01
Moderate heat in combination with pulsed electric fields (PEF) was investigated as a potential alternative to thermal pasteurization of a tropical fruit smoothie based on pineapple, banana, and coconut milk, inoculated with Escherichia coli K12. The smoothie was heated from 25 degrees C to either 45 or 55 degrees C over 60 s and subsequently cooled to 10 degrees C. PEF was applied at electric field strengths of 24 and 34 kV/cm with specific energy inputs of 350, 500, and 650 kJ/L. Both processing technologies were combined using heat (45 or 55 degrees C) and the most effective set of PEF conditions. Bacterial inactivation was estimated on standard and NaCl-supplemented tryptone soy agar (TSA) to enumerate sublethally injured cells. By increasing the temperature from 45 to 55 degrees C, a higher reduction in E. coli numbers (1 compared with 1.7 log(10) colony forming units {CFU} per milliliter, P < 0.05) was achieved. Similarly, as the field strength was increased during stand-alone PEF treatment from 24 to 34 kV/cm, a greater number of E. coli cells were inactivated (2.8 compared with 4.2 log(10) CFU/mL, P < 0.05). An increase in heating temperature from 45 to 55 degrees C during a combined heat/PEF hurdle approach induced a higher inactivation (5.1 compared with 6.9 log(10) CFU/mL, respectively [P < 0.05]) with the latter value comparable to the bacterial reduction of 6.3 log(10) CFU/mL (P> or = 0.05) achieved by thermal pasteurization (72 degrees C, 15 s). A reversed hurdle processing sequence did not affect bacterial inactivation (P> or = 0.05). No differences were observed (P> or = 0.05) between the bacterial counts estimated on nonselective and selective TSA, suggesting that sublethal cell injury did not occur during single PEF treatments or combined heat/PEF treatments.
Opioidergic mechanisms underlying the actions of Vitex agnus-castus L
Webster, Donna E.; He, Ying; Chen, Shao.-Nong; Pauli, Guido F.; Farnsworth, Norman R.; Wang, Zaijie Jim
2010-01-01
Vitex agnus-castus (VAC) has been used since ancient Greek times and has been shown clinically to be effective for the treatment of pre-menstrual syndrome. However, its mechanism of action has only been partially determined. Compounds, fractions, and extracts isolated from VAC were used in this study to thoroughly investigate possible opioidergic activity. First, an extract of VAC was found to bind and activate μ- and δ-, but not κ- opioid receptor subtypes (MOR, DOR, and KOR respectively). The extract was then resuspended in 10% methanol and partitioned sequentially with petroleum ether, CHCl3, and EtOAc to form four fractions including a water fraction. The highest affinity for MOR was concentrated in the CHCl3 fraction, whereas the highest affinity for DOR was found in the CHCl3 and EtOAc fractions. However, the petroleum ether fraction had the highest agonist activity at MOR and DOR. Several flavonoids from VAC were found to bind to both MOR and DOR in a dose-dependent manner; however only casticin, a marker compound for genus Vitex, was found to have agonist activity selective for DOR at high concentrations. These results suggest VAC may exert its therapeutic effects through the activation of MOR, DOR, but not KOR. PMID:20854795
Opioidergic mechanisms underlying the actions of Vitex agnus-castus L.
Webster, Donna E; He, Ying; Chen, Shao-Nong; Pauli, Guido F; Farnsworth, Norman R; Wang, Zaijie Jim
2011-01-01
Vitex agnus-castus (VAC) has been used since ancient Greek times and has been shown clinically to be effective for the treatment of pre-menstrual syndrome. However, its mechanism of action has only been partially determined. Compounds, fractions, and extracts isolated from VAC were used in this study to thoroughly investigate possible opioidergic activity. First, an extract of VAC was found to bind and activate μ- and δ-, but not κ-opioid receptor subtypes (MOR, DOR, and KOR respectively). The extract was then resuspended in 10% methanol and partitioned sequentially with petroleum ether, CHCl(3), and EtOAc to form four fractions including a water fraction. The highest affinity for MOR was concentrated in the CHCl(3) fraction, whereas the highest affinity for DOR was found in the CHCl(3) and EtOAc fractions. The petroleum ether fraction had the highest agonist activity at MOR and DOR. Several flavonoids from VAC were found to bind to both MOR and DOR in a dose-dependent manner; however only casticin, a marker compound for genus Vitex, was found to have agonist activity selective for DOR at high concentrations. These results suggest VAC may exert its therapeutic effects through the activation of MOR, DOR, but not KOR. Copyright © 2010 Elsevier Inc. All rights reserved.
Bardet, Sylvia M; Carr, Lynn; Soueid, Malak; Arnaud-Cormos, Delia; Leveque, Philippe; O'Connor, Rodney P
2016-10-04
Despite the biomedical advances of the last century, many cancers including glioblastoma are still resistant to existing therapies leaving patients with poor prognoses. Nanosecond pulsed electric fields (nsPEF) are a promising technology for the treatment of cancer that have thus far been evaluated in vitro and in superficial malignancies. In this paper, we develop a tumor organoid model of glioblastoma and apply intravital multiphoton microscopy to assess their response to nsPEFs. We demonstrate for the first time that a single 10 ns, high voltage electric pulse (35-45 kV/cm), collapses the perfusion of neovasculature, and also alters the diameter of capillaries and larger vessels in normal tissue. These results contribute to the fundamental understanding of nsPEF effects in complex tissue environments, and confirm the potential of nsPEFs to disrupt the microenvironment of solid tumors such as glioblastoma.
Turk, Mohammad F; Baron, Alain; Vorobiev, Eugene
2010-09-08
This study explored the effect of pulsed electric field (PEF) treatment (E=450 V/cm; tt=10 ms; E<3 kJ/kg) and apple mash size on juice yield, polyphenolic compounds, sugars, and malic acid. Juice yield increased significantly after PEF treatment of large mash (Y=71.4%) and remained higher than the juice yield obtained for a control small mash (45.6%). The acid sweet balance was not altered by PEF. A correlation was established between the decrease of light absorbance (control: 1.43; treated: 1.10) and the decline of native polyphenols yield due to PEF treatment (control: 9.6%; treated: 5.9% for small mash). An enhanced oxidation of phenolic compounds in cells due to electroporation of the inner cell membrane and the adsorption of the oxidized products on the mash may explain both the lower light absorbance and the lower native polyphenol concentration.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kravit, Nancy G.; Schmidt, Katherine A.
The patent application relates to isolated polypeptides that specifically cleave non-glycosidic ether bonds between lignins or derivatives thereof and saccharides, and to cDNAs encoding the polypeptides. The patent application also relates to nucleic acid constructs, expression vectors and host cells comprising the cDNAs, as well as methods of producing and using the isolated polypeptides for treating pulp and biomass to increase soluble saccharide yield and enrich lignin fractions.
Epov, Vladimir N
2011-08-07
A novel approach is suggested to investigate the mechanisms of chemical complexation reactions based on the results of Fujii with co-workers; they have experimentally observed that several metals and metalloids demonstrate mass-independent isotope fractionation during the reactions with the DC18C6 crown ether using solvent-solvent extraction. In this manuscript, the isotope fractionation caused by the magnetic isotope effect is used to understand the mechanisms of chemical exchange reactions. Due to the rule that reactions are allowed for certain electron spin states, and forbidden for others, magnetic isotopes show chemical anomalies during these reactions. Mass-independent fractionation is suggested to take place due to the hyperfine interaction of the nuclear spin with the electron spin of the intermediate product. Moreover, the sign of the mass-independent fractionation is found to be dependent on the element and its species, which is also explained by the magnetic isotope effect. For example, highly negative mass-independent isotope fractionation of magnetic isotopes was observed for reactions of DC18C6 with SnCl(2) species and with several Ru(III) chloro-species, and highly positive for reactions of this ether with TeCl(6)(2-), and with several Cd(II) and Pd(II) species. The atomic radius of an element is also a critical parameter for the reaction with crown ether, particularly the element ions with [Kr]4d(n)5s(m) electron shell fits the best with the DC18C6 crown ring. It is demonstrated that the magnetic isotope effect in combination with the theory of orbital hybridization can help to understand the mechanism of complexation reactions. The suggested approach is also applied to explain previously published mass-independent fractionation of Hg isotopes in other types of chemical exchange reactions. This journal is © the Owner Societies 2011
Validity of peak expiratory flow measurement in assessing reversibility of airflow obstruction.
Dekker, F W; Schrier, A C; Sterk, P J; Dijkman, J H
1992-01-01
BACKGROUND: Assessing the reversibility of airflow obstruction by peak expiratory (PEF) measurements would be practicable in general practice, but its usefulness has not been investigated. METHODS: PEF measurements were performed (miniWright peak flow meter) in 73 general practice patients (aged 40 to 84) with a history of asthma or chronic obstructive lung disease before and after 400 micrograms inhaled sulbutamol. The change in PEF was compared with the change in forced expiratory volume in one second (FEV1). Reversible airflow obstruction was analysed in two ways according to previous criteria. When defined as a 9% or greater increase in FEV1 expressed as a percentage of predicted values reversibility was observed in 42% of patients. Relative operating characteristic analysis showed that an absolute improvement in PEF of 60 l/min or more gave optimal discrimination between patients with reversible and irreversible airflow obstruction (the sensitivity and specificity of an increase of 60 l/min in detecting a 9% or more increase in FEV1 as a percentage of predicted values were 68% and 93% respectively, with a positive predictive value of 87%). When defined as an increase of 190 ml or more in FEV1, reversible airflow obstruction was observed in 53% of patients. Again an absolute improvement in PEF of 60 l/min or more gave optimal discrimination between patients with reversible and irreversible airflow obstruction (sensitivity 56%, specificity 94%, and positive predictive value 92%). CONCLUSION: Absolute changes in PEF can be used as a simple technique to diagnose reversible airflow obstruction in patients from general practice. PMID:1519192
Burgos-Castillo, Rutely C; Sirés, Ignasi; Sillanpää, Mika; Brillas, Enric
2018-03-01
Electrochemical oxidation with electrogenerated H 2 O 2 (EO- H 2 O 2 ), electro-Fenton (EF), photoelectro-Fenton (PEF) and solar PEF (SPEF) have been applied to mineralize bisphenol A solutions in 0.050 M Na 2 SO 4 or 0.008 M NaCl + 0.047 M Na 2 SO 4 at pH 3.0. The assays were performed in an undivided cell with a boron-doped diamond (BDD) anode and an air-diffusion cathode for continuous H 2 O 2 production. The PEF and SPEF processes yielded almost total mineralization due to the potent synergistic action of generated hydroxyl radicals and active chlorine, in conjunction with the photolytic action of UV radiation. The higher intensity of UV rays from sunlight explained the superior oxidation ability of SPEF. The effect of applied current density was studied in all treatments, whereas the role of bisphenol A concentration was examined in PEF. Bisphenol A abatement followed a pseudo-first-order kinetics, which was very quick in SPEF since UV light favored a large production of hydroxyl radicals from Fenton's reaction. Eight non-chlorinated and six chlorinated aromatics were identified as primary products in the chloride matrix. Ketomalonic, tartronic, maleic and oxalic acids were detected as final short-chain aliphatic carboxylic acids. The large stability of Fe(III)-oxalate complexes in EF compared to their fast photomineralization in PEF and PEF accounted for by the superior oxidation power of the latter processes. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
The cytotoxic effect of Elephantopus scaber Linn extract against breast cancer (T47D) cells
NASA Astrophysics Data System (ADS)
Sulistyani, N.; Nurkhasanah
2017-11-01
Breast cancer is one of the main cause of death. Elephantopus scaber Linn (ES) which has been used as a traditional medicine contains an antitumor compounds. This study aimed to explore the active fraction from ethanolic extract of ES as anticancer and to determine its inhibition effect on the cell proliferation cycle of breast cancer (T47D) cells. The ES leaf was macerated with ethanol and then evaporated to get the concentrated extract. The extract was fractionated using petroleum ether, chloroform, and methanol respectively. The cytotoxic activity of each fraction was carried out with MTT method, and the inhibition of cell cycle test were observed by flowcytometry method. The result showed that ES and the fractions have cytotoxic activity against T47D cell lines with IC50 values of extract, petroleum ether, chloroform, and methanol fractions were 58.36±2.38, 132.17±9.69, 7.08±2.11, and 572.89±69.23 µg/mL. The inhibition effect of ethanol extract on the lifecycle of cells was occured in sub G1 phase. There was no prolonging of G1, S, G2/M and polyploidy phase of T47D cell lines. The chloroform fraction of ES is the most cytotoxic fraction against T47D cells without prolonging the cell lifecycle.
Shebaby, Wassim N; Mroueh, Mohamad A; Boukamp, Petra; Taleb, Robin I; Bodman-Smith, Kikki; El-Sibai, Mirvat; Daher, Costantine F
2017-01-10
Previous studies in our laboratory showed that the Lebanese Daucus carota ssp. carota (wild carrot) oil extract possesses in vitro and in vivo anticancer activities. The present study aims to examine the cytotoxic effect of Daucus carota oil fractions on human epidermal keratinocytes and evaluate the chemopreventive activity of the pentane diethyl ether fraction on DMBA/TPA induced skin carcinogenesis in mice. Wild carrot oil extract was chromatographed to yield four fractions (F1, 100% pentane; F2, 50:50 pentane:diethyl ether; F3, 100% diethyl ether; F4 93:7 chloroform:methanol). The cytotoxic effect of fractions (10, 25, 50 and 100 μg/mL) was tested on human epidermal keratinocytes (non-tumorigenic HaCaT cells and tumorigenic HaCaT-ras variants) using WST a ssay. Cell cycle phase distribution of tumorigenic HaCaT-ras variants was determined by flow cytometry post-treatment with F2 fraction. Apoptosis related proteins were also assessed using western blot. The antitumor activity of F2 fraction was also evaluated using a DMBA/TPA induced skin carcinoma in Balb/c mice. All fractions exhibited significant cytotoxicity, with HaCaT cells being 2.4-3 times less sensitive than HaCaT-ras A5 (benign tumorigenic), and HaCaT-ras II4 (malignant) cells. GC-MS analysis revealed the presence of a major compound (around 60%) in the pentane/diethylether fraction (F2), identified as 2-himachalen-6-ol. Treatment of HaCaT-ras A5 and HaCaT-ras II4 cells with F2 fraction resulted in the accumulation of cells in the sub-G1 apoptotic phase and decreased the population of cells in the S and G2/M phases. Additionally, F2 fraction treatment caused an up-regulation of the expression of pro-apoptotic (Bax) and down-regulation of the expression of anti-apoptotic (Bcl2) proteins. A decrease in the phosphorylation of AKT and ERK was also observed. Intraperitoneal treatment with F2 fraction (50 or 200 mg/kg) in the DMBA/TPA skin carcinogenesis mouse model showed a significant inhibition of papilloma incidence (mice with papilloma), yield (number of papilloma/mouse) and volume (tumor relative size) at weeks 15, 18 and 21. The present data reveal that F2 fraction has a remarkable antitumor activity against DMBA/TPA-induced skin carcinogenesis, an effect that may be mediated through inhibition of the MAPK/ERK and PI3K/AKT pathways.
Lam, Jeun-Yan; Shih, Chien-Chung; Lee, Wen-Ya; Chueh, Chu-Chen; Jang, Guang-Way; Huang, Cheng-Jyun; Tung, Shih-Huang; Chen, Wen-Chang
2018-05-30
Exploiting biomass has raised great interest as an alternative to the fossil resources for environmental protection. In this respect, polyethylene furanoate (PEF), one of the bio-based polyesters, thus reveals a great potential to replace the commonly used polyethylene terephthalate (PET) on account of its better mechanical, gas barrier, and thermal properties. Herein, a bio-based, flexible, conductive film is successfully developed by coupling a PEF plastic substrate with silver nanowires (Ag NWs). Besides the appealing advantage of renewable biomass, PEF also exhibits a good transparency around 90% in the visible wavelength range, and its constituent polar furan moiety is revealed to enable an intense interaction with Ag NWs to largely enhance the adhesion of Ag NWs grown above, as exemplified by the superior bending and peeling durability than the currently prevailing PET substrate. Finally, the efficiency of conductive PEF/Ag NWs film in fabricating efficient flexible organic thin-film transistor and organic photovoltaic (OPV) is demonstrated. The OPV device achieves a power conversion efficiency of 6.7%, which is superior to the device based on ITO/PEN device, manifesting the promising merit of the bio-based PEF for flexible electronic applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Role of cytoskeleton and elastic moduli in cellular response to nanosecond pulsed electric fields
NASA Astrophysics Data System (ADS)
Thompson, Gary L.; Roth, Caleb; Tolstykh, Gleb; Kuipers, Marjorie; Ibey, Bennett L.
2013-02-01
Nanosecond pulsed electric fields (nsPEFs) are known to increase cell membrane permeability to small molecules in accordance with dosages. As previous work has focused on nsPEF exposures in whole cells, electrodeformation may contribute to this induced-permeabilization in addition to other biological mechanisms. Here, we hypothesize that cellular elasticity, based upon the cytoskeleton, affects nsPEF-induced decrease in cellular viability. Young's moduli of various types of cells have been calculated from atomic force microscopy (AFM) force curve data, showing that CHO cells are stiffer than non-adherent U937 and Jurkat cells, which are more susceptible to nsPEF exposure. To distinguish any cytoskeletal foundation for these observations, various cytoskeletal reagents were applied. Inhibiting actin polymerization significantly decreased membrane integrity, as determined by relative propidium uptake and phosphatidylserine externalization, upon exposure at 150 kV/cm with 100 pulses of 10 ns pulse width. Exposure in the presence of other drugs resulted in insignificant changes in membrane integrity and 24-hour viability. However, Jurkat cells showed greater lethality than latrunculin-treated CHO cells of comparable elasticity. From these results, it is postulated that cellular elasticity rooted in actin-membrane interaction is only a minor contributor to the differing responses of adherent and non-adherent cells to nsPEF insults.
Buckow, Roman; Semrau, Julius; Sui, Qian; Wan, Jason; Knoerzer, Kai
2012-01-01
A computational fluid dynamics (CFD) model describing the flow, electric field and temperature distribution of a laboratory-scale pulsed electric field (PEF) treatment chamber with co-field electrode configuration was developed. The predicted temperature increase was validated by means of integral temperature studies using thermocouples at the outlet of each flow cell for grape juice and salt solutions. Simulations of PEF treatments revealed intensity peaks of the electric field and laminar flow conditions in the treatment chamber causing local temperature hot spots near the chamber walls. Furthermore, thermal inactivation kinetics of lactoperoxidase (LPO) dissolved in simulated milk ultrafiltrate were determined with a glass capillary method at temperatures ranging from 65 to 80 °C. Temperature dependence of first order inactivation rate constants was accurately described by the Arrhenius equation yielding an activation energy of 597.1 kJ mol(-1). The thermal impact of different PEF processes on LPO activity was estimated by coupling the derived Arrhenius model with the CFD model and the predicted enzyme inactivation was compared to experimental measurements. Results indicated that LPO inactivation during combined PEF/thermal treatments was largely due to thermal effects, but 5-12% enzyme inactivation may be related to other electro-chemical effects occurring during PEF treatments. Copyright © 2012 American Institute of Chemical Engineers (AIChE).
Evaluation of pulsed electric fields technology for liquid whole egg pasteurization.
Monfort, S; Gayán, E; Raso, J; Condón, S; Alvarez, I
2010-10-01
This investigation evaluated the lethal efficiency of pulsed electric fields (PEFs) to pasteurize liquid whole egg (LWE). To achieve this aim, we describe the inactivation of Salmonella Enteritidis and the heat resistant Salmonella Senftenberg 775 W in terms of treatment time and specific energy at electric field strengths ranging from 20 to 45 kV/cm. Based on our results, the target microorganism for this technology in LWE varied with intensity of the PEF treatment. For electric field strengths greater than 25 kV/cm, Salmonella Enteritidis was the most PEF-resistant strain. For this Salmonella serovar the level of inactivation depended only on the specific energy applied: i.e., 106, 272, and 472 kJ/kg for 1, 2, and 3 Log(10) reductions, respectively. The developed mathematical equations based on the Weibull distribution permit estimations of maximum inactivation level of 1.9 Log(10) cycles of the target Salmonella serovar in the best-case scenario: 250 kJ/kg and 25 kV/cm. This level of inactivation indicates that PEF technology by itself cannot guarantee the security of LWE based on USDA and European regulations. The occurrence of cell damage due to PEF in the Salmonella population opens the possibility of designing combined processes enabling increased microbial lethality in LWE. 2010 Elsevier Ltd. All rights reserved.
Dynamics of Voluntary Cough Maneuvers
NASA Astrophysics Data System (ADS)
Naire, Shailesh
2008-11-01
Voluntary cough maneuvers are characterized by transient peak expiratory flows (PEF) exceeding the maximum expiratory flow-volume (MEFV) curve. In some cases, these flows can be well in excess of the MEFV, generally referred to as supramaximal flows. Understanding the flow-structure interaction involved in these maneuvers is the main goal of this work. We present a simple theoretical model for investigating the dynamics of voluntary cough and forced expiratory maneuvers. The core modeling idea is based on a 1-D model of high Reynolds number flow through flexible-walled tubes. The model incorporates key ingredients involved in these maneuvers: the expiratory effort generated by the abdominal and expiratory muscles, the glottis and the flexibility and compliance of the lung airways. Variations in these allow investigation of the expiratory flows generated by a variety of single cough maneuvers. The model successfully reproduces PEF which is shown to depend on the cough generation protocol, the glottis reopening time and the compliance of the airways. The particular highlight is in simulating supramaximal PEF for very compliant tubes. The flow-structure interaction mechanisms behind these are discussed. The wave speed theory of flow limitation is used to characterize the PEF. Existing hypotheses of the origin of PEF, from cough and forced expiration experiments, are also tested using this model.
Wang, Aimin; Zhang, Yanyu; Zhong, Huihui; Chen, Yu; Tian, Xiujun; Li, Desheng; Li, Jiuyi
2018-01-15
In this study, a novel photoelectro-Fenton (PEF) process using microwave discharge electrodeless lamp (MDEL) as a UV irradiation source was developed for the removal of antibiotic ciprofloxacin (CIP) in water. Comparative degradation of 200mgL -1 CIP was studied by direct MDEL photolysis, anodic oxidation (AO), AO in presence of electrogenerated H 2 O 2 (AO-H 2 O 2 ), AO-H 2 O 2 under MDEL irradiation (MDEL-AO-H 2 O 2 ), electro-Fenton (EF) and MDEL-PEF processes. Higher oxidation power was found in the sequence: MDEL photolysis < AO < AO-H 2 O 2 < MDEL-AO-H 2 O 2 < EF < MDEL-PEF. Effects of current density, pH, initial Fe 2+ concentration and initial CIP concentration on TOC removal in MDEL-PEF process were examined, and the optimal conditions were ascertained. The releases of three inorganic ions (F - , NH 4 + and NO 3 - ) and two carboxylic acids (oxalic and formic acids) were qualified. Seven aromatic intermediates mainly generated from hydroxylation, dealkylation and defluorination of CIP were detected by UPLC-QTOF-MS/MS technology. Therefore, plausible degradation sequences for CIP degradation in MDEL-PEF process including all detected products were proposed. Copyright © 2017 Elsevier B.V. All rights reserved.
Li, Jiao-yuan; Ma, Lu; Liu, Li-zhi; Zhou, Jie; He, Ming-quan; Shima, Masayuki; Tamura, Kenji
2013-02-01
To evaluate the effects of indoor and outdoor PM2.5 (fine particulate matter, particulate matter with an aerodynamic diameter ≤ 2.5 µm) on lung function of college students in autumn and winter in Wuhan. In this panel study, 37 college students (excluded subject of respiratory disease and smoking history) aged 19 - 21 were investigated by cluster sampling in a university in Wuhan. The follow-up study lasted for 28 days in total, including two study periods, Oct. 29 to Nov. 11, 2009 (autumn) and Dec. 23, 2009 to Jan.5, 2010 (winter), the peak expiratory flow (PEF) of the college students were measured daily in the morning and evening in the university. PM10 and PM2.5 were monitored indoors and outdoors. The effects of PM on lung function of college students were analyzed by using generalized estimating equation (GEE). Average daily concentrations of indoor, outdoor PM2.5 in autumn were (91.3 ± 43.7) and (104.2 ± 49.4) µg/m(3) respectively, while in winter the concentrations of indoor and outdoor PM2.5 were (110.6 ± 42.3) and (143.5 ± 51.2) µg/m(3). The single pollutant model showed that in winter, the evening PEF decrement was significantly associated with increasing outdoor PM2.5. With an increase of 10 µg/m(3) outdoor PM2.5, the PEF measured in the evening decreased 1.27 L/min (95%CI: 0.02 - 2.52 L/min, respectively). Meanwhile, the results showed that 2-days lagged outdoor PM2.5 was also significantly associated with morning PEF. An increase of 10 µg/m(3) 2-days lagged outdoor PM2.5 caused the decrease of 1.82 L/min (95%CI: -3.53 - -0.11 L/min) of PEF measured in the morning. Controlling the influence of gaseous pollutants and building the two pollutants models, the results indicated that no significant changes of PEF of students being exposed to PM2.5 on same day (lag 0) were observed. However, under consideration of SO2 effect, significant association between an increase of 10 µg/m(3) 2-days lagged outdoor PM2.5 and changes of morning PEF (-1.81 L/min, 95%CI: -3.51 - -0.11 L/min, P = 0.037) was found. The relationship between changes of concentrations and PEF was not observed in autumn in this study. In our panel study, exposure to outdoor PM2.5 is significantly associated with PEF among college students in winter, but not in autumn.
Bers, A Valeria; D'Souza, Fraddry; Klijnstra, Job W; Willemsen, Peter R; Wahl, Martin
2006-01-01
Shells of the blue mussel Mytilus edulis remain free of fouling organisms as long as they possess an intact periostracum, and a multiple antifouling defence that comprises a ripple-like microtopography and the production of chemical antifouling compounds has been suggested previously. This study investigates the chemical defence strategy of blue mussels for the first time. Six crude extracts of the periostracum of intact shells were made using solvents of increasing polarity. These extracts were tested against common fouling organisms in laboratory based bioassays. Non-polar and moderately polar fractions showed the highest activities: the diethyl ether fraction strongly inhibited attachment of Balanus amphitrite cyprids and the marine bacteria Cobetia marina and Marinobacter hydrocarbonoclasticus. Attachment of the benthic diatom Amphora coffeaeformis was significantly reduced by the dichloromethane extract, whereas both ethyl acetate and diethyl ether fractions slowed diatom growth. These results provide the first evidence of surface bound compounds that may moderate surface colonisation.
NASA Astrophysics Data System (ADS)
Steelman, Zachary A.; Tolstykh, Gleb P.; Estlack, Larry E.; Roth, Caleb C.; Ibey, Bennett L.
2015-03-01
Phosphatidylinositol4,5-biphosphate (PIP2) is a membrane phospholipid of particular importance in cell-signaling pathways. Hydrolysis of PIP2 releases inositol-1,4,5-triphosphate (IP3) from the membrane, activating IP3 receptors on the smooth endoplasmic reticulum (ER) and facilitating a release of intracellular calcium stores and activation of protein kinase C (PKC). Recent studies suggest that nanosecond pulsed electric fields (nsPEF) cause depletion of PIP2 in the cellular membrane, activating the IP3 signaling pathway. However, the exact mechanism(s) causing this observed depletion of PIP2 are unknown. Complicating the matter, nsPEF create nanopores in the plasma membrane, allowing calcium to enter the cell and thus causing an increase in intracellular calcium. While elevated intracellular calcium can cause activation of phospholipase C (PLC) (a known catalyst of PIP2 hydrolysis), PIP2 depletion has been shown to occur in the absence of both extracellular and intracellular calcium. These observations have led to the hypothesis that the high electric field itself may be playing a direct role in the hydrolysis of PIP2 from the plasma membrane. To support this hypothesis, we used edelfosine to block PLC and prevent activation of the IP3/DAG pathway in Chinese Hamster Ovarian (CHO) cells prior to applying nsPEF. Fluorescence microscopy was used to monitor intracellular calcium bursts during nsPEF, while MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) survivability assays were utilized to determine whether edelfosine improved cell survival during nsPEF exposure. This work is critical to refine the role of PIP2 in the cellular response to nsPEF, and also to determine the fundamental biological effects of high electric field exposures.
NASA Astrophysics Data System (ADS)
Devecioğlu, İsmail; Güçlü, Burak
2017-02-01
Objective. Recent studies showed that intracortical microstimulation (ICMS) generates artificial sensations which can be utilized as somatosensory feedback in cortical neuroprostheses. To mimic the natural psychophysical response, ICMS parameters are modulated according to psychometric equivalence functions (PEFs). PEFs match the intensity levels of ICMS and mechanical stimuli, which elicit equal detection probabilities, but they typically do not include the frequency as a control variable. We aimed to establish frequency-dependent PEFs for vibrotactile stimulation of the glabrous skin and ICMS in the primary somatosensory cortex of awake freely behaving rats. Approach. We collected psychometric data for vibrotactile and ICMS detection at three stimulation frequencies (40, 60 and 80 Hz). The psychometric data were fitted with a model equation of two independent variables (stimulus intensity and frequency) and four subject-dependent parameters. For each rat, we constructed a separate PEF which was used to estimate the ICMS current amplitude for a given displacement amplitude and frequency. The ICMS frequency was set equal to the vibrotactile frequency. We validated the PEFs in a modified task which included randomly selected probe trials presented either with a vibrotactile or an ICMS stimulus, and also at frequencies and intensity levels not tested before. Main results. The PEFs were generally successful in estimating the ICMS current intensities (no significant differences between vibrotactile and ICMS trials in Kolmogorov-Smirnov tests). Specifically, hit rates from both trial conditions were significantly correlated in 86% of the cases, and 52% of all data had perfect match in linear regression. Significance. The psychometric correspondence model presented in this study was constructed based on surface functions which define psychophysical detection probability as a function of stimulus intensity and frequency. Therefore, it may be used for the real-time modulation of the frequency and intensity of ICMS pulses in somatosensory neuroprostheses.
The association between ambient temperature and children's lung function in Baotou, China
NASA Astrophysics Data System (ADS)
Li, Shanshan; Guo, Yuming; Williams, Gail; Baker, Peter; Ye, Xiaofang; Madaniyazi, Lina; Kim, Dae-Seon; Pan, Xiaochuan
2015-07-01
The objective of this study is to examine the association between ambient temperature and children's lung function in Baotou, China. We recruited 315 children (8-12 years) from Baotou, China in the spring of 2004, 2005, and 2006. They performed three successive forced expiratory measurements three times daily (morning, noon, and evening) for about 5 weeks. The highest peak expiratory flow (PEF) was recorded for each session. Daily data on ambient temperature, relative humidity, and air pollution were monitored during the same period. Mixed models with a distributed lag structure were used to examine the effects of temperature on lung function while adjusting for individual characteristics and environmental factors. Low temperatures were significantly associated with decreases in PEF. The effects lasted for lag 0-2 days. For all participants, the cumulative effect estimates (lag 0-2 days) were -1.44 (-1.93, -0.94) L/min, -1.39 (-1.92, -0.86) L/min, -1.40 (-1.97, -0.82) L/min, and -1.28 (-1.69, -0.88) L/min for morning, noon, evening, and daily mean PEF, respectively, associated with 1 °C decrease in daily mean temperature. Generally, the effects of temperature were slightly stronger in boys than in girls for noon, evening, and daily mean PEF, while the effects were stronger in girls for morning PEF. PM2.5 had joint effects with temperature on children's PEF. Higher PM2.5 increased the impacts of low temperature. Low ambient temperatures are associated with lower lung function in children in Baotou, China. Preventive health policies will be required for protecting children from the cold weather.
Devecioğlu, İsmail; Güçlü, Burak
2017-02-01
Recent studies showed that intracortical microstimulation (ICMS) generates artificial sensations which can be utilized as somatosensory feedback in cortical neuroprostheses. To mimic the natural psychophysical response, ICMS parameters are modulated according to psychometric equivalence functions (PEFs). PEFs match the intensity levels of ICMS and mechanical stimuli, which elicit equal detection probabilities, but they typically do not include the frequency as a control variable. We aimed to establish frequency-dependent PEFs for vibrotactile stimulation of the glabrous skin and ICMS in the primary somatosensory cortex of awake freely behaving rats. We collected psychometric data for vibrotactile and ICMS detection at three stimulation frequencies (40, 60 and 80 Hz). The psychometric data were fitted with a model equation of two independent variables (stimulus intensity and frequency) and four subject-dependent parameters. For each rat, we constructed a separate PEF which was used to estimate the ICMS current amplitude for a given displacement amplitude and frequency. The ICMS frequency was set equal to the vibrotactile frequency. We validated the PEFs in a modified task which included randomly selected probe trials presented either with a vibrotactile or an ICMS stimulus, and also at frequencies and intensity levels not tested before. The PEFs were generally successful in estimating the ICMS current intensities (no significant differences between vibrotactile and ICMS trials in Kolmogorov-Smirnov tests). Specifically, hit rates from both trial conditions were significantly correlated in 86% of the cases, and 52% of all data had perfect match in linear regression. The psychometric correspondence model presented in this study was constructed based on surface functions which define psychophysical detection probability as a function of stimulus intensity and frequency. Therefore, it may be used for the real-time modulation of the frequency and intensity of ICMS pulses in somatosensory neuroprostheses.
Effect of adjusting the combination of budesonide/formoterol on the alleviation of asthma symptoms.
Souma, Ryosuke; Sugiyama, Kumiya; Masuda, Hiroyuki; Arifuku, Hajime; Nakano, Kentaro; Watanabe, Hiroyoshi; Wakayama, Tomoshige; Tokita, Shingo; Tatewaki, Masamitsu; Satoh, Hideyuki; Koyama, Kenya; Hayashi, Yumeko; Fukushima, Fumiya; Hirata, Hirokuni; Arima, Masafumi; Kurasawa, Kazuhiro; Fukuda, Takeshi; Fukushima, Yasutsugu
2018-01-01
The combination of budesonide + formoterol (BFC) offers the advantages of dose adjustment in a single inhaler according to asthma symptoms. We analyzed the relationship between asthma symptoms in terms of peak expiratory flow (PEF) and dose adjustment by the patient. Twenty-eight patients with asthma who used BFC for alleviation of their symptoms (12 men, 16 women; 60 years old) were instructed that the inhaled BFC dose could be increased to a maximum of 8 inhalations per day according to symptom severity. Patients measured and recorded PEF every morning and evening in their asthma diary along with their symptoms and the dose of drugs taken. Sixteen of the 28 patients increased their dose for asthma symptoms. The time to recovery from the asthma symptoms was significantly shorter when cough was the only symptom present compared with dyspnea or wheeze (1.4 vs. 5.3 or 6.6 days, p < 0.05) and when they had only one symptom compared with two or three symptoms (1.3 vs. 5.7 or 10.5, p < 0.01). The relationship between PEF (% of personal best) when the dose was increased (Y) and the days for the increased dose to achieve a PEF greater than PEF in the symptom-free state (X) was determined to be Y = - 0.591X + 89.2 (r 2 = 0.299, p < 0.001). As a guide for increasing the BFC dose when patients with mild asthma have asthma symptoms, the dose should be increased when cough is present or PEF is decreased to 88.9% (i.e., X = 0.5).
Perifornical orexinergic neurons modulate REM sleep by influencing locus coeruleus neurons in rats.
Choudhary, R C; Khanday, M A; Mitra, A; Mallick, B N
2014-10-24
Activation of the orexin (OX)-ergic neurons in the perifornical (PeF) area has been reported to induce waking and reduce rapid eye movement sleep (REMS). The activities of OX-ergic neurons are maximum during active waking and they progressively reduce during non-REMS (NREMS) and REMS. Apparently, the locus coeruleus (LC) neurons also behave in a comparable manner as that of the OX-ergic neurons particularly in relation to waking and REMS. Further, as PeF OX-ergic neurons send dense projections to LC, we argued that the former could drive the LC neurons to modulate waking and REMS. Studies in freely moving normally behaving animals where simultaneously neuro-chemo-anatomo-physio-behavioral information could be deciphered would significantly strengthen our understanding on the regulation of REMS. Therefore, in this study in freely behaving chronically prepared rats we stimulated the PeF neurons without or with simultaneous blocking of specific subtypes of OX-ergic receptors in the LC while electrophysiological recording characterizing sleep-waking was continued. Single dose of glutamate stimulation as well as sustained mild electrical stimulation of PeF (both bilateral) significantly increased waking and reduced REMS as compared to baseline. Simultaneous application of OX-receptor1 (OX1R) antagonist bilaterally into the LC prevented PeF stimulation-induced REMS suppression. Also, the effect of electrical stimulation of the PeF was long lasting as compared to that of the glutamate stimulation. Further, sustained electrical stimulation significantly decreased both REMS duration as well as REMS frequency, while glutamate stimulation decreased REMS duration only. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.
Barrows, F.T.; Lellis, W.A.
1999-01-01
A study was conducted to determine the effect of dietary protein and lipid source on dorsal fin erosion in rainbow trout. Seven diets were each fed to four replicate lots of 300 first-feeding fry cultured in 75 1 aluminum troughs for 8 weeks. Two basal diets were manufactured with approximately equal nutrient content, one using krill and squid meals and the other anchovy meal as the primary protein-containing ingredients. The meals used to manufacture the diets were separated into two fractions: lipid (ether-extractable); and protein/ash (non-ether-extractable) using a large soxhlet. The fractions were then recombined to create two additional diets; one containing anchovy protein/ash with krill/squid lipid, the other krill/squid protein/ash with fish lipid. A fifth diet recombined krill/squid protein/ash with krill/squid lipid to evaluate effects of the extraction process. Two additional treatments included a diet with a portion of the krill meal replaced by poultry by-product meal, and the basal anchovy meal diet supplemented with sodium, magnesium, and copper. Fish consuming diets containing anchovy meal as the primary protein source gained more weight (P < 0.05) than fish consuming krill/squid meal-based diets. Dorsal fin index (DFI, measured as mean dorsal fin height x 100/total fish length) was greater (P < 0.05) for fish consuming diets containing krill/squid meal protein/ash fraction (DFI = 9.9%-10.0%) than for fish consuming diets containing anchovy meal protein/ash fraction (DFI = 4.9%-5.3%), regardless of lipid source. Supplementation of the anchovy meal diet with sodium, magnesium, and copper improved (P < 0.05) DFI by approximately 20%, but not to the level supported by the krill/squid meal protein/ash fraction diets. The cost of the krill meal diet was reduced by inclusion of poultry by-product meal without affecting dorsal fin condition. These data indicate that the dietary agent contributing to dorsal fin erosion in rainbow trout is not present in the ether-extractable fraction of the diet, but rather in the protein or mineral fraction.
Process to convert biomass and refuse derived fuel to ethers and/or alcohols
Diebold, James P.; Scahill, John W.; Chum, Helena L.; Evans, Robert J.; Rejai, Bahman; Bain, Richard L.; Overend, Ralph P.
1996-01-01
A process for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols.
Ki, Dongwon; Parameswaran, Prathap; Popat, Sudeep C; Rittmann, Bruce E; Torres, César I
2015-11-01
The aim of this study was to investigate the combination of two technologies - pulsed electric field (PEF) pre-treatment and semi-continuous pre-fermentation of primary sludge (PS) - to produce volatile fatty acids (VFAs) as the electron donor for microbial electrolysis cells (MECs). Pre-fermentation with a 3-day solids retention time (SRT) led to the maximum generation of VFAs, with or without pretreatment of the PS through pulsed-electric-fields (PEF). PEF treatment before fermentation enhanced the accumulation of the preferred VFA, acetate, by 2.6-fold. Correspondingly, MEC anodes fed with centrate from 3-day pre-fermentation of PEF-treated PS had a maximum current density ∼3.1 A/m(2), which was 2.4-fold greater than the control pre-fermented centrate. Over the full duration of batch MEC experiments, using pre-fermented centrate led to successful performance in terms of Coulombic efficiency (95%), Coulombic recovery (80%), and COD-removal efficiency (85%). Copyright © 2015 Elsevier Ltd. All rights reserved.
Inactivation of Mycobacterium paratuberculosis by Pulsed Electric Fields
Rowan, Neil J.; MacGregor, Scott J.; Anderson, John G.; Cameron, Douglas; Farish, Owen
2001-01-01
The influence of treatment temperature and pulsed electric fields (PEF) on the viability of Mycobacterium paratuberculosis cells suspended in 0.1% (wt/vol) peptone water and in sterilized cow's milk was assessed by direct viable counts and by transmission electron microscopy (TEM). PEF treatment at 50°C (2,500 pulses at 30 kV/cm) reduced the level of viable M. paratuberculosis cells by approximately 5.3 and 5.9 log10 CFU/ml in 0.1% peptone water and in cow's milk, respectively, while PEF treatment of M. paratuberculosis at lower temperatures resulted in less lethality. Heating alone at 50°C for 25 min or at 72°C for 25 s (extended high-temperature, short-time pasteurization) resulted in reductions of M. paratuberculosis of approximately 0.01 and 2.4 log10 CFU/ml, respectively. TEM studies revealed that exposure to PEF treatment resulted in substantial damage at the cellular level to M. paratuberculosis. PMID:11375202
Wu, Li; Zhao, Wei; Yang, Ruijin; Yan, Wenxu
2015-05-15
The aggregation of multi-proteins is of great interest in food processing and a good understanding of the formation of aggregates during PEF processing is needed for the application of the process to pasteurize protein-based foods. The aggregates formation of a multi-protein system (containing ovalbumin, ovotransferrin and lysozyme) was studied through turbidity, size exclusion chromatography and SDS-PAGE patterns for interaction studies and binding forces. Results from size exclusion chromatography indicated that there was no soluble aggregates formed during PEF processing. The existence of lysozyme was important to form insoluble aggregates in the chosen ovalbumin solution. The results of SDS-PAGE patterns indicated that lysozyme was prone to precipitate, and was relatively the higher component of aggregates. Citric acid could be effective in inhibiting lysozyme from interacting with other proteins during PEF processing. Blocking the free sulphydryl by N-ethylmaleimide (NEM) did not affect aggregation inhibition. Copyright © 2014 Elsevier Ltd. All rights reserved.
Abdel-Sattar, Essam; Maes, Louis; Salama, Maha Mahmoud
2010-09-01
The in vitro activity of the methanol extracts of 51 plants randomly collected from the Kingdom of Saudi Arabia and some of their fractions (petroleum ether, chloroform, ethyl acetate and aqueous) were evaluated against Plasmodium falciparum, Trypanosoma brucei brucei, T. cruzi and Leishmania infantum, as well as toxicity against MRC-5 fibroblast cells. Ten crude methanolic extracts that demonstrated potent and adequately selective antiprotozoal activity were subjected to solvent fractionation using petroleum ether, ethyl acetate and chloroform. Only three samples showed promising antiprotozoal activity. Argemone ochroleuca (CHCl(3) fraction) showed pronounced activity against P. falciparum(GHA) (IC(50) 0.32 microg/mL) and T. cruzi (IC(50) 0.30 microg/mL) with low cytotoxicity against MRC-5 cells (CC(50) 11.6 microg/mL). Capparis spinosa (EtOAc fraction) showed pronounced activity against P. falciparum(GHA) with an IC(50) 0.50 microg/mL in the absence of toxicity against MRC-5 cell line (CC(50) > 30 microg/mL). Heliotropium curassavicum (CHCl(3) fraction) showed similar activity against P. falciparum (IC(50) 0.65 microg/mL; MRC-5 CC(50) > 30 microg /mL). These three extracts will be subjected for further extensive studies to isolate and identify their active constituents. Copyright 2010 John Wiley & Sons, Ltd.
Separation of mutagenic components in synthetic crudes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guerin, M. R.; Ho, C. H.; Clark, B. R.
1978-01-01
Mutagenic, basic constituents of a synthetic coal oil and a shale oil were isolated from the crude mixtures. In arriving at an efficient isolation procedure, several liquid chromatographic packing-eluent combinations were tried and the fractions bioassayed to determine the distributions of the mutagenic components. The most effective separation was achieved using a sequential elution scheme with first an alumina-benzene combination followed by a Sephadex LH-20 gel-isopropanol-acetone system. About 75 to 80% of an ether soluble base is eluted with benzene through alumina (activity I). Analysis of this fraction has revealed a wide range of alkyl substituted quinolines and pyridines. Materialmore » remaining on the alumina column was eluted with ethanol, dried and placed on the Sephadex column. Isopropanol (approximately 250 ml) and acetone (approximately 600 ml) were used in that order to elute the material quantitatively. About 12% of the ether-soluble base is eluted with the isopropanol while the rest (approximately 10%) is eluted with the acetone. Additional alkyl pyridine compounds are eluted with isopropanol while the acetone fractions are predominantly multi-ring nitrogen heterocyclic compounds, according to mass spectral analyses. Bioassay data show excellent isolation of the mutagenic activities into the acetone fractions. Negligible activity is found in the sum of the other (90% wt) fractions.« less
Hamdan, Dalia; El-Readi, Mahmoud Zaki; Tahrani, Ahmad; Herrmann, Florian; Kaufmann, Dorothea; Farrag, Nawal; El-Shazly, Assem; Wink, Michael
2011-01-01
Column chromatography of the dichloromethane fraction from an aqueous methanolic extract of fruit peel of Citrus pyriformis Hassk. (Rutaceae) resulted in the isolation of seven compounds including one coumarin (citropten), two limonoids (limonin and deacetylnomilin), and four sterols (stigmasterol, ergosterol, sitosteryl-3-beta-D-glucoside, and sitosteryl-6'-O-acyl-3-beta-D-glucoside). From the ethyl acetate fraction naringin, hesperidin, and neohesperidin were isolated. The dichloromethane extract of the defatted seeds contained three additional compounds, nomilin, ichangin, and cholesterol. The isolated compounds were identified by MS (EI, CI, and ESI), 1H, 13C, and 2D-NMR spectral data. The limonoids were determined qualitatively by LC-ESI/MS resulting in the identification of 11 limonoid aglycones. The total methanolic extract of the peel and the petroleum ether, dichloromethane, and ethyl acetate fractions were screened for their antioxidant and anti-inflammatory activities. The ethyl acetate fraction exhibited a significant scavenging activity for DPPH free radicals (IC50 = 132.3 microg/mL). The petroleum ether fraction inhibited 5-lipoxygenase with IC50 = 30.6 microg/mL indicating potential anti-inflammatory properties. Limonin has a potent cytotoxic effect against COS7 cells [IC50 = (35.0 +/- 6.1) microM] compared with acteoside as a positive control [IC50 = (144.5 +/- 10.96) microM].
Intense picosecond pulsed electric fields inhibit proliferation and induce apoptosis of HeLa cells.
Zhang, Min; Xiong, Zheng-Ai; Chen, Wen-Juan; Yao, Cheng-Guo; Zhao, Zhong-Yong; Hua, Yuan-Yuan
2013-06-01
A picosecond pulsed electric field (psPEF) is a localized physical therapy for tumors that has been developed in recent years, and that may in the future be utilized as a targeted non‑invasive treatment. However, there are limited studies regarding the biological effects of psPEF on cells. Electric field amplitude and pulse number are the main parameters of psPEF that influence its biological effects. In this study, we exposed HeLa cells to a psPEF with a variety of electric field amplitudes, from 100 to 600 kV/cm, and various pulse numbers, from 1,000 to 3,000. An MTT assay was used to detect the growth inhibition, while flow cytometry was used to determine the occurrence of apoptosis and the cell cycle of the HeLa cells following treatment. The morphological changes during cell apoptosis were observed using transmission electron microscopy (TEM). The results demonstrated that the cell growth inhibition rate gradually increased, in correlation with the increasing electric field amplitude and pulse number, and achieved a plateau of maximum cell inhibition 12 h following the pulses. In addition, typical characteristics of HeLa cell apoptosis in the experimental groups were observed by TEM. The results demonstrated that the rate of apoptosis in the experimental groups was significantly elevated in comparison with the untreated group. In the treatment groups, the rate of apoptosis was greater in the higher amplitude groups than in the lower amplitude groups. The same results were obtained when the variable was the pulse number. Flow cytometric analysis indicated that the cell cycle of the HeLa cells was arrested at the G2/M phase following psPEF treatment. Overall, our results indicated that psPEF inhibited cell proliferation and induced cell apoptosis, and that these effects occurred in a dose-dependent manner. In addition, the results demonstrated that the growth of the HeLa cells was arrested at the G2/M phase following treatment. This study may provide a foundation for further in vivo experiments, and for the potential clinical application of psPEF in the treatment of cervical cancer.
Validation of a pulsed electric field process to pasteurize strawberry puree
USDA-ARS?s Scientific Manuscript database
An inexpensive data acquisition method was developed to validate the exact number and shape of the pulses applied during pulsed electric fields (PEF) processing. The novel validation method was evaluated in conjunction with developing a pasteurization PEF process for strawberry puree. Both buffered...
Bakhshabadi, Hamid; Mirzaei, HabibOllah; Ghodsvali, Alireza; Jafari, Seid Mahdi; Ziaiifar, Aman Mohammad
2018-01-01
Application of novel technologies such as microwave and pulsed electric fields (PEF) might increase the speed and efficiency of oil extraction. In the present research, PEF (3.25 kV/cm electric field intensity and 30 pulse number) and microwave (540 W for 180 s) pretreatments were used to study the process of oil extraction from black cumin ( Nigella sativa ) seeds. After applying the selected pretreatments, the oil of seeds was extracted with the use of a screw press and the extraction efficiency, refractive index, oil density, color index, oxidative stability, and chemical components of oil and protein of meal were evaluated. The achieved results expressed that PEF and microwave pretreatments increased the oil extraction efficiency and its oxidative stability. Different pretreatments didn't have any significant influence on the refractive index of black cumin seed oil ( p >.05). When microwave and PEF were used, the oil density showed an enhancement as the following: 1.51% and 0.96%, respectively in comparison with the samples with no pretreatments. Evaluation of the extracted oils, using GC/MS analysis indicated that thymoquinone was the dominant phenolic component in the black cumin oil. Finally, the SEM analysis revealed that microwave and PEF can be useful in the extraction of oil from black cumin seeds since these treatments damaged cell walls and facilitated the oil extraction process.
NASA Astrophysics Data System (ADS)
Thompson, Gary Lee; Roth, Caleb C.; Dalzell, Danielle R.; Kuipers, Marjorie; Ibey, Bennett L.
2014-05-01
The cellular response to subtle membrane damage following exposure to nanosecond pulsed electric fields (nsPEF) is not well understood. Recent work has shown that when cells are exposed to nsPEF, ion permeable nanopores (<2 nm) are created in the plasma membrane in contrast to larger diameter pores (>2 nm) created by longer micro- and millisecond duration pulses. Nanoporation of the plasma membrane by nsPEF has been shown to cause a transient increase in intracellular calcium concentration within milliseconds after exposure. Our research objective is to determine the impact of nsPEF on calcium-dependent structural and repair systems in mammalian cells. Chinese hamster ovary (CHO-K1) cells were exposed in the presence and absence of calcium ions in the outside buffer to either 1 or 20, 600-ns duration electrical pulses at 16.2 kV/cm, and pore size was determined using propidium iodide and calcium green. Membrane organization was observed with morphological changes and increases in FM1-43 fluorescence. Migration of lysosomes, implicated in membrane repair, was followed using confocal microscopy of red fluorescent protein-tagged LAMP1. Microtubule structure was imaged using mEmerald-tubulin. We found that at high 600-ns PEF dosage, calcium-induced membrane restructuring and microtubule depolymerization coincide with interruption of membrane repair via lysosomal exocytosis.
Estimation of the effects of heavy Asian dust on respiratory function by definition type.
Kurai, Jun; Watanabe, Masanari; Noma, Hisashi; Iwata, Kyoko; Taniguchi, Jumpei; Sano, Hiroyuki; Tohda, Yuji; Shimizu, Eiji
2017-01-01
The adverse effects of Asian dust (AD) on health have been demonstrated in earlier studies, but there is no standardized definition for heavy-AD. This study aimed to examine which definition of heavy-AD has the most adverse effect on respiratory function. One-hundred-and-thirty-seven adults with asthma, and 384 school children self-measured their morning peak expiratory flow (PEF). The four definitions of heavy-AD are: (1) the definition provided by the Japan Meteorological Agency (JMA), (2) daily median AD particle level ≥ 0.07 km -1 , obtained through light detection and ranging (LIDAR) (3) hourly AD particle level ≥ 0.1 km -1 , and (4) hourly level ≥ 0.07 km -1 . Linear mixed models were used to estimate the effects of heavy-AD, by definition type, on daily PEF values. In adults with asthma, as per the JMA's definition, significantly reduced PEF were observed on heavy-AD days (lag 0), lag 0-1, and lag 0-3. In school children, after a heavy-AD event, as defined by the JMA, PEF significantly decreased on lag 0-1, lag 0-2, and lag 0-3. However, as per the other definitions, there was no significant decrease in the PEF in the adults and children. The associations between heavy-AD and respiratory function differed between these definitions.
Thompson, Gary Lee; Roth, Caleb C; Dalzell, Danielle R; Kuipers, Marjorie; Ibey, Bennett L
2014-05-01
The cellular response to subtle membrane damage following exposure to nanosecond pulsed electric fields (nsPEF) is not well understood. Recent work has shown that when cells are exposed to nsPEF, ion permeable nanopores (<2 nm) are created in the plasma membrane in contrast to larger diameter pores (>2 nm) created by longer micro- and millisecond duration pulses. Nanoporation of the plasma membrane by nsPEF has been shown to cause a transient increase in intracellular calcium concentration within milliseconds after exposure. Our research objective is to determine the impact of nsPEF on calcium-dependent structural and repair systems in mammalian cells. Chinese hamster ovary (CHO-K1) cells were exposed in the presence and absence of calcium ions in the outside buffer to either 1 or 20, 600-ns duration electrical pulses at 16.2 kV/cm, and pore size was determined using propidium iodide and calcium green. Membrane organization was observed with morphological changes and increases in FM1-43 fluorescence. Migration of lysosomes, implicated in membrane repair, was followed using confocal microscopy of red fluorescent protein-tagged LAMP1. Microtubule structure was imaged using mEmerald-tubulin. We found that at high 600-ns PEF dosage, calcium-induced membrane restructuring and microtubule depolymerization coincide with interruption of membrane repair via lysosomal exocytosis.
The longitudinal relationship of work stress with peak expiratory flow: a cohort study.
Loerbroks, Adrian; Karrasch, Stefan; Lunau, Thorsten
2017-10-01
Research has suggested that psychological stress is associated with reduced lung function and with the development of respiratory disease. Among the major potential sources of stress in adulthood are working conditions. We aimed to examine the relationship of work stress with lung function. We drew on 4-year prospective data from the Survey of Health, Ageing and Retirement in Europe. The analyzed sample comprised 2627 workers aged 50 years or older who were anamnestically free of respiratory disease. Work stress at baseline was operationalized by abbreviated instruments measuring the well-established effort-reward imbalance model (seven items) and the control component of the job-demand control (two items). Peak expiratory flow (PEF) was determined at baseline and at follow-up. Continuous and categorized (i.e., by the tertile) work stress variables were employed in multivariable linear regression models to predict PEF change. Work stress did not show statistically significant associations with PEF change. For instance, the unstandardized regression coefficient for PEF decline according to high versus low effort-reward imbalance was -1.41 (95% confidence interval = -3.75, 0.94). Our study is the first to examine prospective relationships between work stress and PEF. Overall, we did not observe meaningful associations. Future studies should consider a broader spectrum of spirometric parameters and should expand research to younger and possibly less-selected working populations (i.e., aged <50 years).
Cost analysis of commercial pasteurization of orange juice by pulsed electric fields
USDA-ARS?s Scientific Manuscript database
The cost of pulsed electric field (PEF) pasteurization of orange juice was estimated. The cost analysis was based on processing conditions that met the US FDA (5 log reduction) requirement for fruit juice pasteurization and that achieved a 2 month microbial shelf-life. PEF-treated samples processed ...
Ahmed, Farhana; Rahman, Mohammad Sharifur
2016-07-26
Callistemon citrinus (Curtis.) (Family- Myrtaceae) is a popular evergreen shrub in Bangladesh. In the present study, the leaves of this plant have been assessed comprehensively for free radical scavenging, thrombolytic and membrane stabilizing activities. The leaves were collected, powdered and extracted with methanol. The extract was then concentrated and successively fractionated into petroleum ether, carbon tetrachloride, chloroform and aqueous soluble fractions. The extractives were investigated for free radical scavenging, thrombolytic and membrane stabilizing activities. In case of 1,1 diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide radical scavenging assays, the crude methanol extract of the leaves showed the highest free radical scavenging activity among the tested materials including standard ascorbic acid (p = 0.0000). Besides, this extract was also found significantly rich (p = 0.0000) in phenolics and flavonoids compared to other organic fractions. In thrombolytic study, the petroleum ether fraction exhibited significantly stronger thrombolysis (p = 0.024) than other leaf extractives but was weaker than the standard streptokinase. In membrane stabilizing assay, the activity of chloroform fraction was similar to that of standard acetylsalicylic acid (p = 1.000) in hypotonic solution induced hemolysis. However, membrane stabilization activity of this chloroform fraction was found significantly stronger than that of the standard (p = 0.0000) in heat induced hemolysis. This study has revealed the medicinal capabilities of different organic fractions of C. citrinus displaying free radical scavenging, thrombolysis and membrane stabilizing antiinflammatory potentials. Further bioactivity guided isolation is required to obtain pharmacologically secondary metabolites.
Aldana, Jennyfer; Téllez, Nohemí; Gamboa, Fredy
2013-01-01
Dental caries is a multifactorial infectious disease that leads to the destruction of dental hard tissue. The main goal of research into medicinal plants is to seek compounds with antimicrobial activity for subsequent use in prevention strategies and control of infectious diseases. The aim of this study was to evaluate the antimicrobial activity of fractions and subfractions obtained from Elaeagia utilis against Streptococcus mutans, Streptococcus sobrinus and Lactobacillus acidophilus. The plant material was collected in the town of Alban (Cundinamarca, Colombia), which is located at an altitude of 2245 meters above sea level. Two extracts were obtained by cold maceration of E. utilis leaves in (a) petroleum ether extract and (b) ethanol extract. Fractions were obtained from the petroleum ether extract by column vacuum chromatography, and from the ethanol extract by continuous liquid/liquid partitioning. The antimicrobial activity of fractions and subfractions was evaluated by the well diffusion method. At a concentration of 10 mg/well, several fractions from both extracts showed antimicrobial activity against S. mutans, S. sobrinus and L. acidophilus. Among the ethanol extract fractions, the dichloromethane fraction had notably greater antimicrobial activity. It was sub-partitioned, yielding three subfractions with inhibitory activity, of which the most active was MeOH: H2O (Bp) with minimum inhibitory concentration 0.1 mg/well on the 3 study bacteria. Terpenes, sesquiterpenlactones and simple phenolic compounds were identified in it. In conclusion, this study shows the antimicrobial potential of fractions and subfractions obtained from extracts of E. utilis leaves against bacteria that are important in dental caries.
Process to convert biomass and refuse derived fuel to ethers and/or alcohols
Diebold, J.P.; Scahill, J.W.; Chum, H.L.; Evans, R.J.; Rejai, B.; Bain, R.L.; Overend, R.P.
1996-04-02
A process is described for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols. 35 figs.
Genovese, Laura; Lotti, Nadia; Siracusa, Valentina; Munari, Andrea
2017-09-04
In the last decade, there has been an increased interest from the food packaging industry toward the development and application of bioplastics, to contribute to the sustainable economy and to reduce the huge environmental problem afflicting the planet. In the present work, we focus on a new furan-based polyester, poly(neopentyl glycol 2,5-furanoate) (PNF) to be used for sustainable food packaging applications. The aromatic polyester was successfully synthesized with high molecular weight, through a solvent-free process, starting directly from 2,5-furandicarboxylic acid. PNF was revealed to be a material with good thermal stability, characterized by a higher T g and T m and a lower RAF fraction compared to poly(propylene 2,5-furanoate) (PPF), ascribable to the two methyl side groups present in PNF glycol-sub-unit. PNF's mechanical characteristics, i.e., very high elastic modulus and brittle fracture, were found to be similar to those of PPF and PEF. Barrier properties to different gases, temperatures and relative humidity were evaluated. From the results obtained, PNF was showed to be a material with very smart barrier performances, significantly superior with respect to PEF's ones. Lastly, PNF's permeability behavior did not appreciably change after contact with food simulants, whereas it got worse with increasing RH, due to the polar nature of furan ring.
Katsunuma, Toshio; Fujisawa, Takao; Mizuho, Nagao; Akira, Akasawa; Nomura, Ichiro; Yamaoka, Akiko; Kondo, Hisashi; Masuda, Kei; Yamaguchi, Koichi; Terada, Akihiko; Ikeda, Masanori; Nishioka, Kenji; Adachi, Yuichi; Kurihara, Kazuyuki
2013-01-01
Few studies have examined the efficacy or safety of a transdermal β2 agonist as add-on medicationto long-term leukotriene receptor antagonist (LTRA) therapy in pediatric asthma patients. In this randomized, open-label, multicenter clinical trial, children aged 4-12 years on long-term LTRA therapy were treated with tulobuterol patches (1-2 mg daily) or oral sustained-release theophylline (usual dose, 4-5 mg_kg daily) for 4 weeks. LTRAs were continued throughout the trial. Outcomes included volume peak expiratory flow (% PEF), fractional exhaled nitric oxide (FeNO), clinical symptoms and adverse events. Thirty-three and 31 patients were treated with tulobuterol patches and theophylline, respectively. % PEF measured in the morning and before bedtime was significantly higher at all times in the treatment period compared with baseline in the tulobuterol patch group (p < 0.001), and was significantly higher in the tulobuterol patch group compared with the theophylline group. FeNO was similar and unchanged from baseline in both groups. There were no drug-related adverse events in either group. These results suggest that short-term use of a transdermal β2 agonist is an effective therapy for pediatric asthma without inducing airway inflammation in children on long-term LTRA therapy. © 2013 Japanese Society of Allergology.
Nakamura, Yuko; Saito, Yoshiaki; Kubota, Norika; Matsumura, Wataru; Hosoda, Chika; Tamasaki-Kondo, Akiko; Nishimura, Yoko; Sunada, Yoshihide; Fukada, Masuyuki; Ohno, Takako; Maegaki, Yoshihiro; Matsuo, Masafumi; Tokita, Yasuko
2018-03-08
To report on sleep hypercapnia in Becker muscular dystrophy (BMD) at earlier stages than ever recognized. This retrospective study examined nocturnal hypercapnia in six young Becker muscular dystrophy (BMD) patients with deletions of one or more exons of DMD gene. Clinical information, consecutive data on forced vital capacity (FVC%), forced expiratory volume in one second (FEV1%), peak expiratory flow (PEF%), peak cough flow (PCF), average PCO 2 in all-night monitoring, and left ventricular ejection fraction (LVEF) were reviewed. In five BMD patients, including three who were still ambulant, nocturnal average PCO 2 was elevated to >45 mmHg at 12-31 years of age. Noninvasive positive pressure ventilation was initiated in four patients. Gradual declines in FVC% and PEF% were evident in one BMD patient with exon 3-7 deletion, whereas these functions did not change in the remaining BMD patients. PCF, FEV1%, and LVEF were less informative for the assessment of respiratory function in this patient series. Sleep hypercapnia was present in certain BMD patients, which was unexpected from the routine pulmonary function tests. Individualized assessment of nocturnal PCO 2 , partly based on the deletion types, should be further explored in the clinical practice of BMD patients. Copyright © 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Shelf-Life Study of an Orange Juice-Milk Based Beverage after PEF and Thermal Processing
USDA-ARS?s Scientific Manuscript database
The effect of thermal and pulsed electric field (PEF) processing on the shelf-life of an orange juice-milk beverage (OJMB) was studied. The intensities of the treatments were selected to produce similar inactivation of pectin methyl esterase (PME), an enzyme responsible for the jellification and los...
The Relationship among Creative (Mis) Fit, College Culture, Creative and Academic Self-Efficacy
ERIC Educational Resources Information Center
Cayirdag, Nur
2016-01-01
Although person-environment fit (PEF) has been extensively studied in organizational psychology and business literature, its application to educational context has been limited. The current study used PEF framework in terms of creativity within the context of higher education. The nature of relationship between person-environment fit, college…
NASA Astrophysics Data System (ADS)
Ghanshyam, C.; Kaur, Manpreet; Singh, Harjodh; Kapur, Pawan
2011-12-01
Pulsed Electric Field (PEF) is an emerging nonthermal food processing technology being effective in microbial inactivation without impairing the food quality. This paper demonstrates characterization of microbiota present in liquid food so that effective range of PEF can be set accordingly thus depicting the type of microorganism present, its morphology and its cell wall chemistry. The investigated microorganisms included E.coli, Staphylococcus aureus and Listeria monocytogenes, isolated from spoiled orange juice samples. These were characterized through a series of biochemical tests following microscopic (SEM) & spectroscopic (FTIR) characterization. The results were confirmed with respect to Standard MTCC (Microbial Type Culture Collection) strains (MTCC 614, MTCC 96, and MTCC 657). In comparison to Gram negative bacteria, the Gram positive bacteria are more resistant towards PEF. Larger microbial cells require less intense field strength to undergo an equivalent inactivation as compared to smaller cells. Cells in the exponential growth phase are more sensitive than the cells in lag or stationary phase, so it is necessary to identify the predominant bacteria in particular liquid foods.
Buniowska, Magdalena; Carbonell-Capella, Juana M; Frigola, Ana; Esteve, Maria J
2017-04-15
A comparative study of the bioaccessibility of bioactive compounds and antioxidant capacity in a fruit juice-Stevia rebaudiana mixture processed by pulsed electric fields (PEF), high voltage electrical discharges (HVED) and ultrasound (USN) technology at two equivalent energy inputs (32-256kJ/kg) was made using an in vitro model. Ascorbic acid was not detected following intestinal digestion, while HVED, PEF and USN treatments increased total carotenoid bioaccessibility. HVED at an energy input of 32kJ/kg improved bioaccessibility of phenolic compounds (34.2%), anthocyanins (31.0%) and antioxidant capacity (35.8%, 29.1%, 31.9%, for TEAC, ORAC and DPPH assay, respectively) compared to untreated sample. This was also observed for PEF treated samples at an energy input of 256kJ/kg (37.0%, 15.6%, 29.4%, 26.5%, 23.5% for phenolics, anthocyanins, and antioxidant capacity using TEAC, ORAC and DPPH method, respectively). Consequently, pulsed electric technologies (HVED and PEF) show good prospects for enhanced bioaccessibility of compounds with putative health benefit. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Werhahn, Jasper C.; Miliordos, Evangelos; Xantheas, Sotiris S.
2015-01-05
We introduce new generalized (reverting to the original) and extended (not reverting to the original) 4-parameter forms of the (B-2) Potential Energy Function (PEF) of Wang etal. (L.-P. Wang, J. Chen and T. van Voorhis, J. Chem. Theor. Comp. 9, 452 (2013)), which is itself a modification of the Buckingham exponential-6 PEF. The new forms have a tunable, singularity-free short-range repulsion and an adjustable long-range attraction. They produce fits to high quality ab initio data for the X–(H2O), X=F, Cl, Br, I and M+(H2O), M=Li, Na, K, Rb, Cs dimers that are between 1 and 2 orders of magnitude bettermore » than the original 3-parameter (B-2) and modified Buckingham exponential-6 PEFs. They are also slightly better than the 4-parameter generalized Buckingham exponential-6(gBe-6) and of comparable quality with the 4-parameter extended Morse (eM) PEFs introduced recently by us.« less
Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun
2015-01-01
We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk. PMID:26877640
Lee, Gun Joon; Han, Bok Kung; Choi, Hyuk Joon; Kang, Shin Ho; Baick, Seung Chun; Lee, Dong-Un
2015-01-01
We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 μs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk.
Vidal, Jorge; Huiliñir, Cesar; Santander, Rocío; Silva-Agredo, Javier; Torres-Palma, Ricardo A; Salazar, Ricardo
2018-05-15
The elimination of the antibiotic Nafcillin (NAF), which is usually used in hospitals and veterinary clinics around the world, was assessed through a combination of three advanced electrochemical oxidation processes followed by anaerobic digestion process. In the first stage different electrochemical advanced oxidation processes (EAOPs) were used: electro-oxidation with hydrogen peroxide (EO-H 2 O 2 ), electro-Fenton (EF) and Photo electro-Fenton (PEF). After PEF, almost complete and highly efficient degradation and elimination of NAF was achieved, with the concomitant elimination of the associated antimicrobial activity. The fast degradation rate produced by PEF is explained by the oxidative action of hydroxyl radicals (•OH) together with the direct UV photolysis of complexes formed between Fe 3+ and some organic intermediates. Total removal of NAF occurs after 90min of electrolysis by PEF, with the generation of organic intermediates that remain in solution. However, when this post PEF process solution was treated with an anaerobic biological process, the intermediates generated in the electrochemical degradation of NAF were completely eliminated after 24h. The kinetic degradation of NAF as well as the identification/quantification of products and intermediates formed during the degradation of antibiotic, such as inorganic ions, carboxylic acids and aromatic compounds, were determined by chromatographic and photometric methods. Finally, an oxidation pathway is proposed for the complete conversion to CO 2 . Copyright © 2017 Elsevier B.V. All rights reserved.
Personality and Lung Function in Older Adults.
Terracciano, Antonio; Stephan, Yannick; Luchetti, Martina; Gonzalez-Rothi, Ricardo; Sutin, Angelina R
2017-10-01
Lung disease is a leading cause of disability and death among older adults. We examine whether personality traits are associated with lung function and shortness of breath (dyspnea) in a national cohort with and without chronic obstructive pulmonary disease (COPD). Participants (N = 12,670) from the Health and Retirement Study were tested for peak expiratory flow (PEF) and completed measures of personality, health behaviors, and a medical history. High neuroticism and low extraversion, openness, agreeableness, and conscientiousness were associated with lower PEF, and higher likelihood of COPD and dyspnea. Conscientiousness had the strongest and most consistent associations, including lower risk of PEF less than 80% of the predicted value (OR = 0.67; 0.62-0.73) and dyspnea (OR = 0.52; 0.47-0.57). Although attenuated, the associations remained significant when accounting for smoking, physical activity, and chronic diseases including cardiovascular and psychiatric disorders. The associations between personality and PEF or dyspnea were similar among those with or without COPD, suggesting that psychological links to lung function are not disease dependent. In longitudinal analyses, high neuroticism (β = -0.019) and low conscientiousness (β = 0.027) predicted steeper declines in PEF. A vulnerable personality profile is common among individuals with limited lung function and COPD, predicts shortness of breath and worsening lung function. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Palta, Mari; Sadek-Badawi, Mona; Madden, Kathleen; Green, Christopher
2007-09-01
We determined lung function at age 10 years in very low birthweight (VLBW,
Cossio-Bolaños, Marco; Lee-Andruske, Cynthia; de Arruda, Miguel; Luarte-Rocha, Cristian; Almonacid-Fierro, Alejandro; Gómez-Campos, Rossana
2018-03-02
Maintaining and building healthy bones during the lifetime requires a complicated interaction between a number of physiological and lifestyle factors. Our goal of this study was to analyze the association between hand grip strength and the maximum peak expiratory flow with bone mineral density and content in adolescent students. The research team studied 1427 adolescent students of both sexes (750 males and 677 females) between the ages of 11.0 and 18.9 years in the Maule Region of Talca (Chile). Weight, standing height, sitting height, hand grip strength (HGS), and maximum peak expiratory flow (PEF) were measured. Furthermore, bone mineral density (BMD) and total body bone mineral content (BMC) were determined by using the Dual-Energy X-Ray Absorptiometry (DXA). Hand grip strength and PEF were categorized in tertiles (lowest, middle, and highest). Linear regression was performed in steps to analyze the relationship between the variables. Differences between categories were determined through ANOVA. In males, the hand grip strength explained 18-19% of the BMD and 20-23% of the BMC. For the females, the percentage of variation occurred between 12 and 13% of the BMD and 17-18% of the BMC. The variation of PEF for the males was observed as 33% of the BMD and 36% of the BMC. For the females, both the BMD and BMC showed a variation of 19%. The HGS and PEF were divided into three categories (lowest, middle, and highest). In both cases, significant differences occurred in bone density health between the three categories. In conclusion, the HGS and the PEF related positively to the bone density health of both sexes of adolescent students. The adolescents with poor values for hand grip strength and expiratory flow showed reduced values of BMD and BMC for the total body. Furthermore, the PEF had a greater influence on bone density health with respect to the HGS of the adolescents of both sexes.
NASA Technical Reports Server (NTRS)
Call, Jared A.; Kwok, John H.; Fisher, Forest W.
2013-01-01
This innovation is a tool used to verify and validate spacecraft sequences at the predicted events file (PEF) level for the GRAIL (Gravity Recovery and Interior Laboratory, see http://www.nasa. gov/mission_pages/grail/main/index. html) mission as part of the Multi-Mission Planning and Sequencing Team (MPST) operations process to reduce the possibility for errors. This tool is used to catch any sequence related errors or issues immediately after the seqgen modeling to streamline downstream processes. This script verifies and validates the seqgen modeling for the GRAIL MPST process. A PEF is provided as input, and dozens of checks are performed on it to verify and validate the command products including command content, command ordering, flight-rule violations, modeling boundary consistency, resource limits, and ground commanding consistency. By performing as many checks as early in the process as possible, grl_pef_check streamlines the MPST task of generating GRAIL command and modeled products on an aggressive schedule. By enumerating each check being performed, and clearly stating the criteria and assumptions made at each step, grl_pef_check can be used as a manual checklist as well as an automated tool. This helper script was written with a focus on enabling the user with the information they need in order to evaluate a sequence quickly and efficiently, while still keeping them informed and active in the overall sequencing process. grl_pef_check verifies and validates the modeling and sequence content prior to investing any more effort into the build. There are dozens of various items in the modeling run that need to be checked, which is a time-consuming and errorprone task. Currently, no software exists that provides this functionality. Compared to a manual process, this script reduces human error and saves considerable man-hours by automating and streamlining the mission planning and sequencing task for the GRAIL mission.
Raffrenato, E; Fievisohn, R; Cotanch, K W; Grant, R J; Chase, L E; Van Amburgh, M E
2017-10-01
The objective of this study was to correlate in vitro and in vivo neutral detergent fiber (NDF) digestibility (NDFD) with the chemical composition of forages and specific chemical linkages, primarily ester- and ether-linked para-coumaric (pCA) and ferulic acids (FA) in forages fed to dairy cattle. The content of acid detergent lignin (ADL) and its relationship with NDF does not fully explain the observed variability in NDFD. The ferulic and p-coumaric acid linkages between ADL and cell wall polysaccharides, rather than the amount of ADL, might be a better predictor of NDFD. Twenty-three forages, including conventional and brown midrib corn silages and grasses at various stages of maturity were incubated in vitro for measurement of 24-h and 96-h NDFD. Undigested and digested residues were analyzed for NDF, acid detergent fiber (ADF), ADL, and Klason lignin (KL); ester- and ether-linked pCA and FA were determined in these fractions. To determine whether in vitro observations of ester- and ether-linked pCA and FA and digestibility were similar to in vivo observations, 3 corn silages selected for digestibility were fed to 6 ruminally fistulated cows for 3 wk in 3 iso-NDF diets. Intact samples and NDF and ADF residues of diet, rumen, and feces were analyzed for ester- and ether-linked pCA and FA. From the in vitro study, the phenolic acid content (total pCA and FA) was highest for corn silages, and overall the content of ester- and ether-linked pCA and FA in both NDF and ADF residues were correlated with NDF digestibility parameters, reflecting the competitive effect of these linkages on digestibility. Also, Klason lignin and ADL were negatively correlated with ether-linked ferulic acid on an NDF basis. Overall, esterified FA and esterified pCA were negatively correlated with all of the measured fiber fractions on both a dry matter and an NDF basis. The lignin content of the plant residues and chemical linkages explained most of the variation in both rate and extent of NDF digestion but not uniformly among forages, ranging from 56 to 99%. The results from the in vivo study were similar to the in vitro data, demonstrating the highest total-tract aNDF digestibility (70%; NDF analysis conducted with α-amylase and sodium sulfite) for cows fed the corn silage with the lowest ester- and ether-linked pCA content in the NDF fraction. In this study, digestibility of forage fiber was influenced by the linkages among lignin and the carbohydrate moieties, which vary by hybrid and species and most likely vary by the agronomic conditions under which the plant was grown. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Chen, LiPing; Shen, XuanRi; Chen, GuoHua; Cao, XianYing; Yang, Jian
2015-01-01
Three-Spot seahorse is a traditional medicine in Asian countries. However, the alcohol extract is largely unknown for its anti-inflammatory activity. This study aimed at elucidating fraction of potent anti-inflammatory activity of seahorse. A systematic solvent extraction method of liquid-liquid fractionation of ethanol crude extract gave four fractions petroleum ether (PE), and ethyl acetate (EtOAc), water saturated butanol (n-BuOH), water (H2O). In this study, PE extract was selected for further study after preliminary screening test, and was connected to silica column chromatography and eluted with different polarity of mobile phases, and obtained four active fractions (Fr I, Fr II, Fr III, Fr IV). Effect of separated fractions on inflammation was investigated in lipopolysaccharide (LPS) stimulated murine RAW264.7 cells in vitro. The result shows that seahorse extract was capable of inhibiting the production of nitric oxide (NO) significantly in a dose dependent manner and exhibited no notable cytotoxicity on cell viability. IC50 of fraction IV was 36.31 μg/mL, indicating that separated fraction possessed potent NO inhibitory activity against LPS-induced inflammatory response, thus, demonstrated its in vitro anti-inflammatory potentiality, it may be at least partially explained by the presence of anti-inflammation active substances, phenolic compounds, phospholipids and polyunsaturated fatty acids, especially phospholipids and polyunsaturated fatty acids. It could be suggested that seahorse lipid-soluble components could be used in functional food and anti-inflammatory drug preparations.
USDA-ARS?s Scientific Manuscript database
Fresh blueberries were pretreated by pulsed electric fields (PEF) at 3 kV/cm or thermal pretreatment at 90 degrees C for 5 min after which they were subject to osmotic dehydration. The changes in contents of anthocyanins, predominantly phenolic acids and flavonols, total phenolics, polyphenol oxidas...
Penobscot Experimental Forest: 60 years of research and demonstration in Maine, 1950-2010
Laura S. Kenefic; John C. Brissette
2014-01-01
The Penobscot Experimental Forest (PEF) in Maine has been the site of U.S. Department of Agriculture, Forest Service, Northern Research Station (previously Northeastern Forest Experiment Station) research on northern conifer silviculture and ecology since 1950. Purchased by forest industry and leased to the Forest Service for long-term experimentation, the PEF was...
Pankiewicz, Urszula; Sujka, Monika; Jamroz, Jerzy
2015-12-01
The obtained results demonstrated an influence of PEF on increase in accumulation of various ions in S. cerevisiae cells. Optimization of particular PEF parameters and ions concentrations in the medium caused twofold increase in accumulation of magnesium and zinc ions and 3.5-fold higher accumulation of calcium ions in the cells. In the case of ion couple, accumulation of magnesium and zinc was, respectively, 1.5-fold and twofold higher in comparison to the control cultures. Yeast cells biomass enriched with Mg(2+), Zn(2+), Ca(2+) as well as Mg(2+) and Zn(2+) (simultaneously) may be an alternative for pharmacological supplementation applied in deficiency of these cations.
CONDUCT AN INVESTIGATION OF CIGUATERA POISON
Research on ciguatera toxin has resulted in the development of an efficient method for extracting the toxin from the musculature of fish. Procedures...solution and adsorption of ciguatera toxin on silicic ac d. More precise fractionation of ciguatera toxin is accomplished on a silicic acid column...developed in stepwise fashion by ether containing small percentages of methanol.As a method for fractionation and as the basis for a test for ciguatera
Enteromorpha compressa Exhibits Potent Antioxidant Activity
Shanab, Sanaa M. M.; Shalaby, Emad A.; El-Fayoumy, Eman A.
2011-01-01
The green macroalgae, Enteromorpha compressa (Linnaeus) Nees, Ulva lactuca, and E. linza, were seasonally collected from Abu Qir bay at Alexandria (Mediterranean Sea) This work aimed to investigate the seasonal environmental conditions, controlling the green algal growth, predominance, or disappearance and determining antioxidant activity. The freshly collected selected alga (E. compressa) was subjected to pigment analysis (chlorophyll and carotenoids) essential oil and antioxidant enzyme determination (ascorbate oxidase and catalase). The air-dried ground alga was extracted with ethanol (crude extract) then sequentially fractionated by organic solvents of increasing polarity (petroleum ether, chloroform, ethyl acetate, and water). Antioxidant activity of all extracts was assayed using different methods (total antioxidant, DPPH [2, 2 diphenyl-1-picrylhydrazyl], ABTS [2, 2 azino-bis ethylbenzthiazoline-6-sulfonic acid], and reducing power, and β-carotene linoleic acid bleaching methods). The results indicated that the antioxidant activity was concentration and time dependent. Ethyl acetate fraction demonstrated higher antioxidant activity against DPPH method (82.80%) compared to the synthetic standard butylated hydroxyl toluene (BHT, 88.5%). However, the crude ethanolic extract, pet ether, chloroform fractions recorded lower to moderate antioxidant activities (49.0, 66.0, and 78.0%, resp.). Using chromatographic and spectroscopic analyses, an active compound was separated and identified from the promising ethyl acetate fraction. PMID:21869863
Hsieh, Chih-Hsiung; Lu, Chueh-Hsuan; Chen, Wei-Ting; Ma, Bo-Lun
2017-01-01
Traditional therapies for pancreatic cancer are usually expensive and likely to cause side effects, and most patients have the risk of recurrence and suffering pain. Here, we investigated combination treatment of epigallocatechin-3-gallate (EGCG) and non-invasive low strength pulsed electric field (PEF) on the human pancreatic cell line PANC-1. Cells were cultured in various concentrations of EGCG and exposed to trains of PEF. The results showed that the low strength PEF alone or single treatment with low concentration of EGCG did not obviously affect the cell proliferation and migration in PANC-1. However, the EGCG-induced inhibitions of cell viability and migration ability in PANC-1 were dramatically enhanced by the further exposure of low strength PEF (60 V/cm). In particular, the same combination treatment caused less inhibition of cell viability in non-malignant HEK293 cells. We also found the combination treatment significantly decreased the ratio of Bcl-2/Bax protein and increased caspase activity in PANC-1 cells, resulting in the promotion of apoptotic responses, evidenced by chromatin condensation. The findings of the present study reveal the synergistic reactions in the combination treatment may severely disturb mitochondria, enhance the intrinsic pathway transduction, and effectively induce apoptosis; moreover, the migration and invasion of PANC-1 cancer cells were also significantly suppressed. Since normal cells are less sensitive to this combination treatment, and the non-invasive PEF could be modified to focus on a specific location, this treatment may serve as a promising method for anti-cancer therapy. PMID:29186186
Hsieh, Chih-Hsiung; Lu, Chueh-Hsuan; Chen, Wei-Ting; Ma, Bo-Lun; Chao, Chih-Yu
2017-01-01
Traditional therapies for pancreatic cancer are usually expensive and likely to cause side effects, and most patients have the risk of recurrence and suffering pain. Here, we investigated combination treatment of epigallocatechin-3-gallate (EGCG) and non-invasive low strength pulsed electric field (PEF) on the human pancreatic cell line PANC-1. Cells were cultured in various concentrations of EGCG and exposed to trains of PEF. The results showed that the low strength PEF alone or single treatment with low concentration of EGCG did not obviously affect the cell proliferation and migration in PANC-1. However, the EGCG-induced inhibitions of cell viability and migration ability in PANC-1 were dramatically enhanced by the further exposure of low strength PEF (60 V/cm). In particular, the same combination treatment caused less inhibition of cell viability in non-malignant HEK293 cells. We also found the combination treatment significantly decreased the ratio of Bcl-2/Bax protein and increased caspase activity in PANC-1 cells, resulting in the promotion of apoptotic responses, evidenced by chromatin condensation. The findings of the present study reveal the synergistic reactions in the combination treatment may severely disturb mitochondria, enhance the intrinsic pathway transduction, and effectively induce apoptosis; moreover, the migration and invasion of PANC-1 cancer cells were also significantly suppressed. Since normal cells are less sensitive to this combination treatment, and the non-invasive PEF could be modified to focus on a specific location, this treatment may serve as a promising method for anti-cancer therapy.
Vijayalakshmi, Subramanian; Nadanasabhapathi, Shanmugam; Kumar, Ranganathan; Sunny Kumar, S
2018-03-01
The presence of aflatoxin, a carcinogenic and toxigenic secondary metabolite produced by Aspergillus species, in food matrix has been a major worldwide problem for years now. Food processing methods such as roasting, extrusion, etc. have been employed for effective destruction of aflatoxins, which are known for their thermo-stable nature. The high temperature treatment, adversely affects the nutritive and other quality attributes of the food, leading to the necessity of application of non-thermal processing techniques such as ultrasonication, gamma irradiation, high pressure processing, pulsed electric field (PEF), etc. The present study was focused on analysing the efficacy of the PEF process in the reduction of the toxin content, which was subsequently quantified using HPLC. The process parameters of different pH model system (potato dextrose agar) artificially spiked with aflatoxin mix standard was optimized using the response surface methodology. The optimization of PEF process effects on the responses aflatoxin B1 and total aflatoxin reduction (%) by pH (4-10), pulse width (10-26 µs) and output voltage (20-65%), fitted 2FI model and quadratic model respectively. The response surface plots obtained for the processes were of saddle point type, with the absence of minimum or maximum response at the centre point. The implemented numerical optimization showed that the predicted and actual values were similar, proving the adequacy of the fitted models and also proved the possible application of PEF in toxin reduction.
Comparison of five portable peak flow meters.
Takara, Glaucia Nency; Ruas, Gualberto; Pessoa, Bruna Varanda; Jamami, Luciana Kawakami; Di Lorenzo, Valéria Amorim Pires; Jamami, Mauricio
2010-05-01
To compare the measurements of spirometric peak expiratory flow (PEF) from five different PEF meters and to determine if their values are in agreement. Inaccurate equipment may result in incorrect diagnoses of asthma and inappropriate treatments. Sixty-eight healthy, sedentary and insufficiently active subjects, aged from 19 to 40 years, performed PEF measurements using Air Zone, Assess, Galemed, Personal Best and Vitalograph peak flow meters. The highest value recorded for each subject for each device was compared to the corresponding spirometric values using Friedman's test with Dunn's post-hoc (p<0.05), Spearman's correlation test and Bland-Altman's agreement test. The median and interquartile ranges for the spirometric values and the Air Zone, Assess, Galemed, Personal Best and Vitalograph meters were 428 (263-688 L/min), 450 (350-800 L/min), 420 (310-720 L/min), 380 (300-735 L/min), 400 (310-685 L/min) and 415 (335-610 L/min), respectively. Significant differences were found when the spirometric values were compared to those recorded by the Air Zone(R) (p<0.001) and Galemed (p<0.01) meters. There was no agreement between the spirometric values and the five PEF meters. The results suggest that the values recorded from Galemed meters may underestimate the actual value, which could lead to unnecessary interventions, and that Air Zone meters overestimate spirometric values, which could obfuscate the need for intervention. These findings must be taken into account when interpreting both devices' results in younger people. These differences should also be considered when directly comparing values from different types of PEF meters.
NASA Astrophysics Data System (ADS)
Bajaj, Pushp; Wang, Xiao-Gang; Carrington, Tucker; Paesani, Francesco
2018-03-01
Full-dimensional vibrational spectra are calculated for both X-(H2O) and X-(D2O) dimers (X = F, Cl, Br, I) at the quantum-mechanical level. The calculations are carried out on two sets of recently developed potential energy functions (PEFs), namely, Thole-type model energy (TTM-nrg) and many-body energy (MB-nrg), using the symmetry-adapted Lanczos algorithm with a product basis set including all six vibrational coordinates. Although both TTM-nrg and MB-nrg PEFs are derived from coupled-cluster single double triple-F12 data obtained in the complete basis set limit, they differ in how many-body effects are represented at short range. Specifically, while both models describe long-range interactions through the combination of two-body dispersion and many-body classical electrostatics, the relatively simple Born-Mayer functions employed in the TTM-nrg PEFs to represent short-range interactions are replaced in the MB-nrg PEFs by permutationally invariant polynomials to achieve chemical accuracy. For all dimers, the MB-nrg vibrational spectra are in close agreement with the available experimental data, correctly reproducing anharmonic and nuclear quantum effects. In contrast, the vibrational frequencies calculated with the TTM-nrg PEFs exhibit significant deviations from the experimental values. The comparison between the TTM-nrg and MB-nrg results thus reinforces the notion that an accurate representation of both short-range interactions associated with electron density overlap and long-range many-body electrostatic interactions is necessary for a correct description of hydration phenomena at the molecular level.
Gurtler, Joshua B; Rivera, Rebecca B; Zhang, Howard Q; Geveke, David J
2010-04-30
Pulsed electric field (PEF) technology has been used for the inactivation of microorganisms and to prevent flavor loss in liquid foods and beverages in place of thermal pasteurization. When used to pasteurize orange juice, PEF may prevent loss of volatile sensory attributes. Enterohemorrhagic E. coli O157:H7 (EHEC), two strains of Salmonella Typhimurium, and twenty strains of non-pathogenic bacteria were screened for inactivation in orange juice by PEF at 22 and 20kV/cm at 45 and 55 degrees C, respectively. Higher populations of both salmonellae were inactivated (2.81 and 3.54 log CFU/ml) at 55 degrees C, in comparison with the reduction of EHEC (2.22 log). When tested under the same conditions, inactivation of EHEC was slightly greater than that of a non-pathogenic E. coli (NPEC) ATCC 35218 (2.02 log). NPEC was further tested as a surrogate for EHEC by comparing inactivation kinetics at 45, 50 and 55 degrees C at field strengths of between 7.86 and 32.55kV/cm. Statistical comparison of revealed that EHEC and NPEC inactivation curves were homogeneous at outlet temperatures of 45 and 50 degrees C; however, EHEC was slightly more sensitive to PEF than the surrogate NPEC at 55 degrees C. The higher PEF resistance of non-pathogenic E. coli 35218 at 55 degrees C may provide a desirable margin of safety when used in pilot plant challenge studies in place of E. coli O157:H7. Published by Elsevier B.V.
Flores, Nelly; Cabot, Pere Lluís; Centellas, Francesc; Garrido, José Antonio; Rodríguez, Rosa María; Brillas, Enric; Sirés, Ignasi
2017-01-05
The degradation of 4-hydroxyphenylacetic acid, a ubiquitous component of olive oil mill wastewater (OOMW), has been studied by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed in either a 0.050M Na 2 SO 4 solution or a real OOMW at pH 3.0, using a cell with a boron-doped diamond (BDD) anode and an air-diffusion cathode for H 2 O 2 generation. Hydroxyl radicals formed at the BDD surface from water oxidation in all processes and/or in the bulk from Fenton's reaction between added Fe 2+ and generated H 2 O 2 in EF and PEF were the main oxidants. In both matrices, the oxidation ability of the processes increased in the order AO-H 2 O 2
Impulse oscillometry: a measure for airway obstruction.
Vink, Geraldine R; Arets, Hubertus G M; van der Laag, Johan; van der Ent, Cornelis K
2003-03-01
The impulse oscillometry system (IOS) was introduced as a new technique to assess airflow obstruction in patients who are not able to perform forced breathing maneuvers, e.g., subjects with cerebral palsy or severe mental retardation, and young children. This study evaluates the sensitivity and specificity of IOS parameters to quantify changes in airflow obstruction in comparison with forced expiratory volume in the first second (FEV(1)) and peak expiratory flow (PEF) measurements. Measurements of FEV(1), PEF, and resistance (R) and reactance (X) at frequencies of 5-35 Hz were performed in 19 children with asthma before, during, and after methacholine challenge and subsequent bronchodilatation. All parameters changed significantly during tests. Values of R5 and R10 correlated with FEV(1) (r = -0.71 and -0.73, respectively, P < 0.001), as did values of X5 and X10 (r = 0.52 and 0.57, respectively, P < 0.01). Changes in R preceded changes in PEF and FEV(1) during methacholine challenge. The area under the receiver operating characteristic (ROC) curve to predict a 15% fall in FEV(1) showed better sensitivity and specificity for R5 (area under the curve, 0.85) compared to PEF (0.79) or R10 (0.73). We conclude that IOS parameters can be easily used as an indirect measure of airflow obstruction. This might be helpful in patients who are not able to perform forced breathing maneuvers. In individual subjects, R values measured at 5 Hz showed to be superior to PEF measurements in the detection of a 15% fall in FEV(1). Copyright 2003 Wiley-Liss, Inc.
Effect of Personal Exposure to PM2.5 on Respiratory Health in a Mexican Panel of Patients with COPD
Cortez-Lugo, Marlene; Ramírez-Aguilar, Matiana; Sansores-Martínez, Raúl; Pérez-Padilla, Rogelio; Ramírez-Venegas, Alejandra; Barraza-Villarreal, Albino
2015-01-01
Background: Air pollution is a problem, especially in developing countries. We examined the association between personal exposure to particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5) on respiratory health in a group of adults with chronic obstructive pulmonary disease (COPD). Methods: All participants resided in Mexico City and during follow-up, personal exposure to PM2.5, respiratory symptoms, medications, and daily activity were registered daily. Peak expiratory flow (PEF) was measured twice daily, from February through December, 2000, in 29 adults with moderate, severe, and very severe COPD. PEF changes were estimated for each 10 µg/m3 increment of PM2.5, adjustment for severity of COPD, minimum temperature, and day of the sampling. Results: For a 10-µg/m3 increase in the daily average of a two-day personal exposure to PM2.5, there was a significant 33% increase in cough (95% CI, range, 5‒69%), and 23% in phlegm (95% CI, range, 2‒54%), a reduction of the PEF average in the morning of −1.4 L/min. (95% CI , range, −2.8 to −0.04), and at night of −3.0 L/min (95% CI, range, −5.7 to −0.3), respectively. Conclusions: Exposure to PM2.5 was associated with reductions in PEF and increased respiratory symptoms in adults with COPD. The PEF reduction was observed both at morning and at night. PMID:26343703
USDA-ARS?s Scientific Manuscript database
Whole fresh blueberries were treated using a parallel pulsed electric field (PEF) treatment chamber and a sanitizer solution (60 ppm peracetic acid [PAA]) as PEF treatment medium with square wave bipolar pulses at 2 kV/cm electric field strength, 1us pulse width, and 100 pulses per second for 2, 4, ...
Gonzalez, Maria E; Barrett, Diane M
2010-01-01
Advanced food processing methods that accomplish inactivation of microorganisms but minimize adverse thermal exposure are of great interest to the food industry. High pressure (HP) and pulsed electric field (PEF) processing are commercially applied to produce high quality fruit and vegetable products in the United States, Europe, and Japan. Both microbial and plant cell membranes are significantly altered following exposure to heat, HP, or PEF. Our research group sought to quantify the degree of damage to plant cell membranes that occurs as a result of exposure to heat, HP, or PEF, using the same analytical methods. In order to evaluate whether new advanced processing methods are superior to traditional thermal processing methods, it is necessary to compare them. In this review, we describe the existing state of knowledge related to effects of heat, HP, and PEF on both microbial and plant cells. The importance and relevance of compartmentalization in plant cells as it relates to fruit and vegetable quality is described and various methods for quantification of plant cell membrane integrity are discussed. These include electrolyte leakage, cell viability, and proton nuclear magnetic resonance (1H-NMR). PMID:20492210
Impact of nanosecond pulsed electric fields on primary hippocampal neurons
NASA Astrophysics Data System (ADS)
Roth, Caleb C.; Payne, Jason A.; Kuipers, Marjorie A.; Thompson, Gary L.; Wilmink, Gerald J.; Ibey, Bennett L.
2012-02-01
Cellular exposure to nanosecond pulsed electric fields (nsPEF) are believed to cause immediate creation of nanopores in the plasma membrane. These nanopores enable passage of small ions, but remain impermeable to larger molecules like propidium iodide. Previous work has shown that nanopores are stable for minutes after exposure, suggesting that formation of nanopores in excitable cells could lead to prolonged action potential inhibition. Previously, we measured the formation of nanopores in neuroblastoma cells by measuring the influx of extracellular calcium by preloading cells with Calcium Green-AM. In this work, we explored the impact of changing the width of a single nsPEF, at constant amplitude, on uptake of extracellular calcium ions by primary hippocampal neurons (PHN). Calcium Green was again used to measure the influx of extracellular calcium and FM1-43 was used to monitor changes in membrane conformation. The observed thresholds for nanopore formation in PHN by nsPEF were comparable to those measured in neuroblastoma. This work is the first study of nsPEF effects on PHN and strongly suggests that neurological inhibition by nanosecond electrical pulses is highly likely at doses well below irreversible damage.
Gonzalez, Maria E; Barrett, Diane M
2010-09-01
Advanced food processing methods that accomplish inactivation of microorganisms but minimize adverse thermal exposure are of great interest to the food industry. High pressure (HP) and pulsed electric field (PEF) processing are commercially applied to produce high quality fruit and vegetable products in the United States, Europe, and Japan. Both microbial and plant cell membranes are significantly altered following exposure to heat, HP, or PEF. Our research group sought to quantify the degree of damage to plant cell membranes that occurs as a result of exposure to heat, HP, or PEF, using the same analytical methods. In order to evaluate whether new advanced processing methods are superior to traditional thermal processing methods, it is necessary to compare them. In this review, we describe the existing state of knowledge related to effects of heat, HP, and PEF on both microbial and plant cells. The importance and relevance of compartmentalization in plant cells as it relates to fruit and vegetable quality is described and various methods for quantification of plant cell membrane integrity are discussed. These include electrolyte leakage, cell viability, and proton nuclear magnetic resonance (¹H-NMR).
Exploring Membrane Dynamics during Electric Pulse Exposure with Second Harmonic Generation
NASA Astrophysics Data System (ADS)
Moen, Erick; Ibey, Bennett; Beier, Hope; Armani, Andrea
Optical second harmonic generation (SHG) is a powerful tool for investigating the nanostructure of symmetry-breaking materials and interfacial layers. Recently, we developed an imaging technique based on SHG for quantifying and localizing nanoporation in the plasma membrane of living cells. Nanosecond pulsed electric fields (nsPEF) were used to controllably disrupt the membrane, and the observed changes were validated against an extensible cell circuit model. In this talk, I will discuss the development of this method and its application to various cell types and stimuli, with a specific focus on bipolar (BP) nsPEF. BP nsPEF hold special interest as a cellular insult because they allow for a unique exposition of transmembrane potential and membrane charging/relaxation. Using this approach, we examine the structural response of the membrane as the temporal spacing between pulse phases was varied over several orders of magnitude and compare these results to the response when the cell is exposed to a monopolar (MP) nsPEF. Disagreement of the experimental results with the model demonstrates that biological processes may play a larger role than previously thought. These findings could lead to a greater understanding of the fundamental processes essential to all electroporation.
Methylation patterns of aquatic humic substances determined by 13C NMR spectroscopy
Thorn, K.A.; Steelink, C.; Wershaw, R. L.
1987-01-01
13C NMR spectroscopy is used to examine the hydroxyl group functionality of a series of humic and fulvic acids from different aquatic environments. Samples first are methylated with 13C-labeled diazomethane. The NMR spectra of the diazomethylated samples allow one to distinguish between methyl esters of carboxylic acids, methyl ethers of phenolic hydroxyls, and methyl ethers of phenolic hydroxyls adjacent to two substituents. Samples are then permethylated with 13C-labeled methyl iodide/NaH. 13C NMR spectra of permethylated samples show that a significant fraction of the hydroxyl groups is not methylated with diazomethane alone. In these spectra methyl ethers of carbohydrate and aliphatic hydroxyls overlap with methyl ethers of phenolic hydroxyls. Side reactions of the methyltion procedure including carbon methylation in the CH3I/NaH procedure, are also examined. Humic and fulvic acids from bog, swamp, groundwater, and lake waters showssome differences in their distribution of hydroxyl groups, mainly in the concentrations of phenolic hydroxyls, which may be attributed to their different biogeochemical origins. ?? 1987.
Anticonvulsive activity of Butea monosperma flowers in laboratory animals.
Kasture, Veena S; Kasture, S B; Chopde, C T
2002-07-01
The bioassay-guided fractionation of dried flowers of Butea monosperma (BM) was carried out to isolate the active principle responsible for its anticonvulsant activity. The petroleum ether extract was fractionated by column chromatography using solvents of varying polarity such as n-hexane, n-hexane:ethyl acetate, ethyl acetate, and methanol. The anticonvulsive principle of B. monosperma was found to be a triterpene (TBM) present in the n-hexane:ethyl acetate (1:1) fraction of the petroleum ether extract. TBM exhibited anticonvulsant activity against seizures induced by maximum electroshock (MES) and its PD(50) was found to be 34.2+/-18.1 mg/kg. TBM also inhibited seizures induced by pentylenetetrazol (PTZ), electrical kindling, and the combination of lithium sulfate and pilocarpine nitrate (Li-Pilo). However, TBM was not effective against seizures induced by strychnine and picrotoxin. TBM exhibited depressant effect on the central nervous system. After repeated use for 7 days, the PD(50) (MES) of TBM increased to 51.5+/-12.1 mg/kg. Similarly, after repeated use of TBM, the duration of sleep induced by pentobarbital was not reduced significantly. Further studies are required to investigate its usefulness in the treatment of epilepsy.
Capillary break-up, gelation and extensional rheology of hydrophobically modified cellulose ethers
NASA Astrophysics Data System (ADS)
Sharma, Vivek; Haward, Simon; Pessinet, Olivia; Soderlund, Asa; Threlfall-Holmes, Phil; McKinley, Gareth
2012-02-01
Cellulose derivatives containing associating hydrophobic groups along their hydrophilic polysaccharide backbone are used extensively in the formulations for inks, water-borne paints, food, nasal sprays, cosmetics, insecticides, fertilizers and bio-assays to control the rheology and processing behavior of multi-component dispersions. These complex dispersions are processed and used over a broad range of shear and extensional rates. The presence of hydrophobic stickers influences the linear and nonlinear rheology of cellulose ether solutions. In this talk, we systematically contrast the difference in the shear and extensional rheology of a cellulose ether: ethy-hydroxyethyl-cellulose (EHEC) and its hydrophobically-modified analog (HMEHEC) using microfluidic shear rheometry at deformation rates up to 10^6 inverse seconds, cross-slot flow extensional rheometry and capillary break-up during jetting as a rheometric technique. Additionally, we provide a constitutive model based on fractional calculus to describe the physical gelation in HMEHEC solutions.
Antioxidant Activity in the Extracts of Two Edible Aroids
Mandal, P.; Misra, T. K.; Singh, I. D.
2010-01-01
Two neglected species of Araceae, Alocasia macrorhiza (Linn.) G. Don and Alocasia fornicata (Roxb.) Schott are important as food and ethno medicine in Asia and Africa. Their bioefficacy is documented in the Ayurveda. The solvent extracts of different edible parts of these two species like rhizomes, leaves, roots and stolons were screened for in vitro antioxidant properties using standard procedures. The successive extracts in hexane, benzene, toluene, chloroform, diethyl ether, ethyl acetate and water fraction exhibited IC50 values in the following order, roots>rhizome>leaves for Alocasia macrorhiza and leaves>stolon for Alocasia fornicate, respectively in 2,2-diphenyl-1-picryl hydrazyl antioxidant inhibition assay. Maximum antioxidant activity was observed in diethyl ether extracts for both species. The IC50 values were comparable with those of quercetine and ascorbic acid as standards. These results suggest that the two aroid species have antioxidant activity in their edible parts and should be extracted using diethyl ether solvent. PMID:20582198
Reineke, Kai; Schottroff, Felix; Meneses, Nicolas; Knorr, Dietrich
2015-01-01
The intention of this study was to investigate the inactivation of endospores by a combined thermal and pulsed electric field (PEF) treatment. Therefore, self-cultivated spores of Bacillus subtilis and commercial Geobacillus stearothermophilus spores with certified heat resistance were utilized. Spores of both strains were suspended in saline water (5.3 mS cm(-1)), skim milk (0.3% fat; 5.3 mS cm(-1)) and fresh prepared carrot juice (7.73 mS cm(-1)). The combination of moderate preheating (70-90°C) and an insulated PEF-chamber, combined with a holding tube (65 cm) and a heat exchanger for cooling, enabled a rapid heat up to 105-140°C (measured above the PEF chamber) within 92.2-368.9 μs. To compare the PEF process with a pure thermal inactivation, each spore suspension was heat treated in thin glass capillaries and D-values from 90 to 130°C and its corresponding z-values were calculated. For a comparison of the inactivation data, F-values for the temperature fields of both processes were calculated by using computational fluid dynamics (CFD). A preheating of saline water to 70°C with a flow rate of 5 l h(-1), a frequency of 150 Hz and an energy input of 226.5 kJ kg(-1), resulted in a measured outlet temperature of 117°C and a 4.67 log10 inactivation of B. subtilis. The thermal process with identical F-value caused only a 3.71 log10 inactivation. This synergism of moderate preheating and PEF was even more pronounced for G. stearothermophilus spores in saline water. A preheating to 95°C and an energy input of 144 kJ kg(-1) resulted in an outlet temperature of 126°C and a 3.28 log10 inactivation, whereas nearly no inactivation (0.2 log10) was achieved during the thermal treatment. Hence, the PEF technology was evaluated as an alternative ultra-high temperature process. However, for an industrial scale application of this process for sterilization, optimization of the treatment chamber design is needed to reduce the occurring inhomogeneous temperature fields.
Improving asthma control through telemedicine: a study of short-message service.
Ostojic, Vedran; Cvoriscec, Branimir; Ostojic, Sanja Barsic; Reznikoff, Dimitry; Stipic-Markovic, Asja; Tudjman, Zdenko
2005-02-01
Home peak expiratory flow (PEF) measurement is recommended by asthma guidelines. In a 16-week randomized controlled study on 16 subjects with asthma (24.6 6.5 years old, asthma duration small ze, Cyrillic 6 months), we examined Global System for Mobile Communications (GSM) mobile telephone short-message service (SMS) as a novel means of telemedicine in PEF monitoring. All subjects received asthma education, self-management plan, and standard treatment. All measured PEF three times daily and kept a symptom diary. In the study group, therapy was adjusted weekly by an asthma specialist according to PEF values received daily from the patients. There was no significant difference between the groups in absolute PEF, but PEF variability was significantly smaller in the study group (16.12 +/- 6.93% vs. 27.24 +/- 10.01%, p = 0.049). forced expiratory flow in 1 second (FEV1; % predicted) in the study group was slightly but significantly increased (81.25 +/- 17.31 vs. 77.63 +/- 14.80, p = 0.014) and in the control group, unchanged (78.25 +/- 21.09 vs. 78.88 +/- 22.02, p = 0.497). Mean FEV1 was similar in the two groups both before and after the study. Controls had significantly higher scores for cough (1.85 +/- 0.43 vs. 1.42 +/- 0.28, p < 0.05) and night symptoms (1.22 +/- 0.23 vs. 0.85 +/- 0.32, p < 0.05). There was no significant difference between the groups in daily consumption of inhaled medicine, forced vital capacity, or compliance. Per patient, per week, the additional cost of follow-up by SMS was Euros 1.67 (equivalent to approximately $1.30 per 1 Euro), and SMS transmission required 11.5 minutes. Although a study group of 40 patients is needed for the follow-up study to achieve the power of 80% within the 95% confidence interval, we conclude that SMS is a convenient, reliable, affordable, and secure means of telemedicine that may improve asthma control when added to a written action plan and standard follow-up.
Al-Musayeib, Nawal; Ebada, Sherif S; Gad, Haidy A; Youssef, Fadia S; Ashour, Mohamed Lotfy
2017-10-01
Genus Ficus (Moraceae) constitutes more than 850 species and about 2000 varieties and it acts as a golden mine that could afford effective and safe remedies combating many health disorders. Discrimination of Ficus cordata , Ficus ingens , and Ficus palmata using chemometric analysis and assessment of their role in combating oxidative stress. Phytochemical profiling of the methanol extracts of the three Ficus species and their successive fractions was performed using high-performance liquid chromatography/electrospray ionization mass spectrometry. Their discrimination was carried out using the obtained spectral data applying chemometric unsupervised pattern-recognition techniques, namely, principal component analysis and hierarchical cluster analysis. In vitro hepatoprotective and antioxidant evaluation of the samples was performed using human hepatocellular carcinoma cells challenged by carbon tetrachloride (CCl 4 ). Altogether, 22 compounds belonging to polyphenolics, flavonoids, and furanocoumarins were identified in the three Ficus species. Aviprin is the most abundant compound in F. cordata while chlorogenic acid and psoralen were present in high percentages in F. ingens and F. palmata , respectively. Chemometric analyses showed that F. palmata and F. cordata are more closely related chemically to each other rather than F. ingens . The ethyl acetate fractions of all the examined species showed a marked hepatoprotective efficacy accounting for 54.78%, 55.46%, and 56.42% reduction in serum level of alanine transaminase and 56.82%, 54.16%, and 57.06% suppression in serum level of aspartate transaminase, respectively, at 100 μg/mL comparable to CCl 4 -treated cells. Ficus species exhibited a no table antioxidant and hepatoprotective activity owing to their richness in polyphenolics and furanocoumarins. Ficus cordata , Ficus ingens , and Ficus palmata were analyzed using high-performance liquid chromatography/electrospray ionization mass spectrometry that revealed their richness with polyphenolics and furanocoumarinsDiscrimination of the three species was performed using spectral data coupled with chemometrics that showed that F. palmata and F. cordata are chemically related to each other rather than F. ingens In vitro hepatoprotective and antioxidant evaluation was performed using human hepatocellular carcinoma cells. The ethyl acetate fractions of all the examined species showed a marked hepatoprotective efficacy Ficus species exhibited notable activities due to polyphenolics and furanocoumarins. Abbreviations used: ALT: Alanine transaminase, AST: Aspartate transaminase, CCl 4: Carbon tetrachloride, DMEM: Dulbecco's Modified Eagle's medium, DMSO: Dimethyl sulfoxide, EDTA: Ethylenediaminetetraacetic acid, FBS: Fetal bovine serum, FCA: Ficus cordata remaining aqueous fraction, FCB: Ficus cordata n -butanol fraction, FCE: Ficus cordata ethyl acetate fraction, FCP: Ficus cordata petroleum ether fraction, FCT: Ficus cordata total methanol extract, FIA: Ficus ingens remaining aqueous fraction, FIB: Ficus ingens n -butanol fraction, FIE: Ficus ingens ethyl acetate fraction, FIP: Ficus ingens petroleum ether fraction, FIT: Ficus ingens total methanol extract, FPA: Ficus palmata remaining aqueous fraction, FPB: Ficus palmata n -butanol fraction, FPE: Ficus palmata ethyl acetate fraction, FPP: Ficus palmata petroleum ether fraction, FPT: Ficus palmata total methanol extract, GSH: Reduced glutathione, HepG2 cells: Human hepatocellular carcinoma, HPLC-ESI-MS: High-performance liquid chromatography/electrospray ionization mass spectrometry, and SOD: Superoxide dismutase.
Comparison of five portable peak flow meters
Takara, Glaucia Nency; Ruas, Gualberto; Pessoa, Bruna Varanda; Jamami, Luciana Kawakami; Di Lorenzo, Valéria Amorim Pires; Jamami, Mauricio
2010-01-01
OBJECTIVE To compare the measurements of spirometric peak expiratory flow (PEF) from five different PEF meters and to determine if their values are in agreement. Inaccurate equipment may result in incorrect diagnoses of asthma and inappropriate treatments. METHODS Sixty-eight healthy, sedentary and insufficiently active subjects, aged from 19 to 40 years, performed PEF measurements using Air Zone®, Assess®, Galemed®, Personal Best® and Vitalograph® peak flow meters. The highest value recorded for each subject for each device was compared to the corresponding spirometric values using Friedman’s test with Dunn’s post-hoc (p<0.05), Spearman’s correlation test and Bland-Altman’s agreement test. RESULTS The median and interquartile ranges for the spirometric values and the Air Zone®, Assess®, Galemed®, Personal Best® and Vitalograph® meters were 428 (263–688 L/min), 450 (350–800 L/min), 420 (310–720 L/min), 380 (300–735 L/min), 400 (310–685 L/min) and 415 (335–610 L/min), respectively. Significant differences were found when the spirometric values were compared to those recorded by the Air Zone® (p<0.001) and Galemed ® (p<0.01) meters. There was no agreement between the spirometric values and the five PEF meters. CONCLUSIONS The results suggest that the values recorded from Galemed® meters may underestimate the actual value, which could lead to unnecessary interventions, and that Air Zone® meters overestimate spirometric values, which could obfuscate the need for intervention. These findings must be taken into account when interpreting both devices’ results in younger people. These differences should also be considered when directly comparing values from different types of PEF meters. PMID:20535364
Evaluation of the turbine pocket spirometer.
Gunawardena, K A; Houston, K; Smith, A P
1987-01-01
A compact electronic spirometer, the turbine pocket spirometer, which measures the FEV1, forced vital capacity (FVC), and peak expiratory flow (PEF) in a single expiration, was compared with the Vitalograph and the Wright peak flow meter in 99 subjects (FEV1 range 0.40-5.50 litres; FVC 0.58-6.48 l; PEF 40-650 l min-1). The mean differences between the machines were small--0.05 l for FEV1, 0.05 l for FVC, and 11.6 l min-1 for PEF, with the limits of agreement at +/- 0.25 l, +/- 0.48 l, and +/- 52.2 l min-1 respectively. The wide limits of agreement for the PEF comparison were probably because of the difference in the technique of blowing: a fast, long blow was used for the pocket spirometer and a short, sharp one for the Wright peak flow meter. The FEV1 and FVC showed a proportional bias of around 4-5% in favour of the Vitalograph. The repeatability coefficient for the pocket spirometer FEV1 was 0.18 l, for FVC 0.22 l, and for PEF 31 l min-1. These compared well with the repeatability coefficients of the Vitalograph and the Wright peak flow meter, which gave values of 0.18 l, 0.28 l, and 27 l min-1 respectively. At flow rates of over 600 l min-1 the resistance of the pocket spirometer marginally exceeded the American Thoracic Society recommendations. The machine is easy to operate and portable, and less expensive than the Vitalograph and Wright peak flow meter combined. It can be recommended for general use. Images PMID:3686460
Villegas-Guzman, Paola; Hofer, Florian; Silva-Agredo, Javier; Torres-Palma, Ricardo A
2017-12-01
Taking ciprofloxacin (CIP) as a fluoroquinolone antibiotic model, this work explores the role of common anions (sulfate, nitrate, and chloride) during the application of photoelectro-Fenton (PEF) at natural pH to degrade this type of compound in water. The system was composed of an IrO 2 anode, Ti, or gas diffusion electrode (GDE) as cathode, Fe 2+ , and UV (254 nm). To determine the implications of these anions, the degradation pathway and efficiency of the PEF sub-processes (UV photolysis, anodic oxidation, and electro-Fenton at natural pH) were studied in the individual presence of the anions. The results highlight that degradation routes and kinetics are strongly dependent on electrolytes. When chloride and nitrate ions were present, indirect electro-chemical oxidation was identified by electro-generated HOCl and nitrogenated oxidative species, respectively. Additionally, direct photolysis and direct oxidation at the anode surface were identified as degradation routes. As a consequence of the different pathways, six primary CIP by-products were identified. Therefore, a scheme was proposed representing the pathways involved in the degradation of CIP when submitted to PEF in water with chloride, nitrate, and sulfate ions, showing the complexity of this process. Promoted by individual and synergistic actions of this process, the PEF system leads to a complete elimination of CIP with total removal of antibiotic activity against Staphylococcus aureus and Escherichia coli, and significant mineralization. Finally, the role of the anions was tested in seawater containing CIP, in which the positive contributions of the anions were partially suppressed by its OH radical scavenger action. The findings are of interest for the understanding of the degradation of antibiotics via the PEF process in different matrices containing sulfate, nitrate, and chloride ions.
Wu, Limei; Yao, Chenguo; Xiong, Zhengai; Zhang, Ruizhe; Wang, Zhiliang; Wu, Yutong; Qin, Qin; Hua, Yuanyuan
2016-04-01
The application of picosecond pulsed electric field (psPEF) is a new biomedical engineering technique used in cancer therapy. However, its effects on cervical cancer angiogenesis are not clear. Therefore, the aim of the present study is to investigate the effects of psPEF on angiogenesis in cervical cancer xenograft models. Xenograft tumors were created by subcutaneously inoculating nude mice (athymic BALB/c nu/nu mice) with HeLa cells, then were placed closely between tweezer-type plate electrodes and subjected to psPEF with a gradually increased electric field intensity (0kV/cm, 50kV/cm, 60kV/cm, 70kV/cm). The direct effect on tumor tissue was observed by hematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM). The changes of blood vessels and oxygen saturation (sO2) of tumors were monitored in vivo by photoacoustic tomography (PAT). The microvessel density (MVD), vascular endothelial growth factor (VEGF) and hypoxia-inducible transcription factors (HIF-1α and HIF-2α) were detected by immunohistochemical technique (IHC). Their protein expressions and gene transcription levels were evaluated using western blot (WB) and quantitative reverse transcription and polymerase chain reaction (RT-PCR). PsPEF induced obvious necrosis of cervical cancer tissue; with the increasing of electric field intensity, the MVD, vascular PA signal and sO2 values declined significantly. The protein expression and gene transcription levels of VEGF, HIF1α and HIF2α were significantly decreased at the same time. PsPEF exhibited dramatic anti-tumor and anti-angiogenesis effects in cervical cancer xenograft models by exerting direct effect on cancer cells and vascular endothelial cells and indirect effect on tumor angiogenesis-related factors. Copyright © 2016 Elsevier Inc. All rights reserved.
Puértolas, E; Saldaña, G; Condón, S; Alvarez, I; Raso, J
2009-01-01
The effect of the addition of 2 enzymatic preparations and the application of a pulsed electric fields treatment (PEF) on the phenolic content and color of Cabernet Sauvignon wine has been compared. The evolution of color intensity (CI), anthocyanic content (AC), and total polyphenol index (TPI) from crushing to 3 mo of aging in bottle was studied. The results demonstrated that both treatments promoted greater extraction of phenolic compounds, compared to the untreated wine. However, PEF technology was more effective. After 3 mo of storage, CI, AC, and TPI were 28%, 26%, and 11%, respectively, higher in PEF-wine than in control wine. By contrast, while both enzymatic preparations increased the CI of the wine around 5%, only one of them increased the AC and TPI by 11% and 3%, respectively, in comparison with the control. After 3 mo of aging in bottle, the phenolic composition was also analyzed by high-performance liquid chromatography (HPLC). The content of nonanthocyanic families was higher in PEF-wine than in the rest of the wines. In wines treated by enzymes, only an increase in phenolic acids and flavonols with respect to the control was detected. Practical Application: Pulsed electric fields is a novel food processing technology that poses a very promising future to the enological field, due to its capacity to improve the mass transfer phenomenon. The continuous development of this technology allows nowadays the application of treatments at the semi-industrial scale. In this article, it has been demonstrated that the application of a PEF treatment to the grape pomace before maceration/fermentation is more effective, in terms of color intensity and phenolic content, than the addition of macerating enzymes.
Kon, Takahide; Nemoto, Naoki; Oshima, Tairo; Yamagishi, Akihiko
2002-01-01
The archaeal plasma membrane consists mainly of diether lipids and tetraether lipids instead of the usual ester lipids found in other organisms. Although a molecule of tetraether lipid is thought to be synthesized from two molecules of diether lipids, there is no direct information about the biosynthetic pathway(s) or intermediates of tetraether lipid biosynthesis. In this study, we examined the effects of the fungal squalene epoxidase inhibitor terbinafine on the growth and ether lipid biosyntheses in the thermoacidophilic archaeon Thermoplasma acidophilum. Terbinafine was found to inhibit the growth of T. acidophilum in a concentration-dependent manner. When growing T. acidophilum cells were pulse-labeled with [2-14C]mevalonic acid in the presence of terbinafine, incorporation of radioactivity into the tetraether lipid fraction was strongly suppressed, while accumulation of radioactivity was noted at the position corresponding to diether lipids, depending on the concentration of terbinafine. After the cells were washed with fresh medium and incubated further without the radiolabeled substrate and the inhibitor, the accumulated radioactivity in the diether lipid fraction decreased quickly while that in the tetraether lipids increased simultaneously, without significant changes in the total radioactivity of ether lipids. These results strongly suggest that terbinafine inhibits the biosynthesis of tetraether lipids from a diether-type precursor lipid(s). The terbinafine treatment will be a tool for dissecting tetraether lipid biosynthesis in T. acidophilum. PMID:11844769
USDA-ARS?s Scientific Manuscript database
Bioassay-guided fractionation of Cladosporium cladosporioides crude extracts led to the isolation of four compounds, including cladosporin (1), isocladosporin (2), 5'-hydroxyasperentin (3), cladosporin-8-methyl ether (4). The compound 6, 5'-diacetyl cladosporin (5) was synthesized by acetylation of ...
Identification of the toxic compounds produced by Sargassum thunbergii to red tide microalgae
NASA Astrophysics Data System (ADS)
Wang, Renjun; Wang, You; Tang, Xuexi
2012-09-01
The inhibitory effects of methanol extracts from the tissues of three macroalgal species on the growths of three marine red tide microalgae were assessed under laboratory conditions. Extracts of Sargassum thunbergii (Mertens ex Roth) Kuntz tissue had stronger inhibitory effects than those of either Sargassum pallidum (Turner) C. Agardh or Sargassum kjellmanianum Yendo on the growths of Heterosigma akashiwo (Hada) Hada, Skeletonema costatum (Grev.) Grev, and Prorocentrum micans Ehrenberg. Methanol extracts of S. thunbergii were further divided into petroleum ether, ethyl acetate, butanol, and distilled water phases by liquid-liquid fractionation. The petroleum ether and ethyl acetate fractions had strong algicidal effects on the microalgae. Gas chromatography-mass spectrometry analyses of these two phases identified nine fatty acids, most of which were unsaturated fatty acids. In addition, pure compounds of four of the nine unsaturated fatty acids had effective concentrations below 5 mg/L. Therefore, unsaturated fatty acids are a component of the allelochemicals in S. thunbergii tissue.
USDA-ARS?s Scientific Manuscript database
Pulse Electric Field (PEF) treatment has been used to inactivate bacteria in liquid foods. However, information on the behavior of PEF injured Escherichia coli bacteria in media during storage at 5 and 23C are limited. In this study, we investigated the fate of E. coli O157:H7 cells at 6.8 log CFU/m...
Targeted cellular ablation based on the morphology of malignant cells
NASA Astrophysics Data System (ADS)
Ivey, Jill W.; Latouche, Eduardo L.; Sano, Michael B.; Rossmeisl, John H.; Davalos, Rafael V.; Verbridge, Scott S.
2015-11-01
Treatment of glioblastoma multiforme (GBM) is especially challenging due to a shortage of methods to preferentially target diffuse infiltrative cells, and therapy-resistant glioma stem cell populations. Here we report a physical treatment method based on electrical disruption of cells, whose action depends strongly on cellular morphology. Interestingly, numerical modeling suggests that while outer lipid bilayer disruption induced by long pulses (~100 μs) is enhanced for larger cells, short pulses (~1 μs) preferentially result in high fields within the cell interior, which scale in magnitude with nucleus size. Because enlarged nuclei represent a reliable indicator of malignancy, this suggested a means of preferentially targeting malignant cells. While we demonstrate killing of both normal and malignant cells using pulsed electric fields (PEFs) to treat spontaneous canine GBM, we proposed that properly tuned PEFs might provide targeted ablation based on nuclear size. Using 3D hydrogel models of normal and malignant brain tissues, which permit high-resolution interrogation during treatment testing, we confirmed that PEFs could be tuned to preferentially kill cancerous cells. Finally, we estimated the nuclear envelope electric potential disruption needed for cell death from PEFs. Our results may be useful in safely targeting the therapy-resistant cell niches that cause recurrence of GBM tumors.
Chen, Xinhua; Ren, Zhigang; Zhu, Tongyin; Zhang, Xiongxin; Peng, Zhiyi; Xie, Haiyang; Zhou, Lin; Yin, Shengyong; Sun, Junhui; Zheng, Shusen
2015-01-01
Irreversible electroporation (IRE) with microsecond-pulsed electric fields (μsPEFs) can effectively ablate hepatocellular carcinomas in animal models. This preclinical study evaluates the feasibility and safety of IRE on porcine livers. Altogether, 10 pigs were included. Computed tomography (CT) was used to guide two-needle electrodes that were inserted near the hilus hepatis and gall bladder. Animals were followed-up at 2 hours and at 2, 7 and 14 days post-treatment. During and after μsPEF ablation, electrocardiographs found no cardiovascular events, and contrast CT found no portal vein thrombosis. There was necrosis in the ablation zone. Mild cystic oedema around the gall bladder was found 2 hours post-treatment. Pathological studies showed extensive cell death. There was no large vessel damage, but there was mild endothelial damage in some small vessels. Follow-up liver function tests and routine blood tests showed immediate liver function damage and recovery from the damage, which correlated to the pathological changes. These results indicate that μsPEF ablation affects liver tissue and is less effective in vessels, which enable μsPEFs to ablate central tumour lesions close to the hilus hepatis and near large vessels and bile ducts, removing some of the limitations and contraindications of conventional thermal ablation. PMID:26549662
Chen, Xinhua; Ren, Zhigang; Zhu, Tongyin; Zhang, Xiongxin; Peng, Zhiyi; Xie, Haiyang; Zhou, Lin; Yin, Shengyong; Sun, Junhui; Zheng, Shusen
2015-11-09
Irreversible electroporation (IRE) with microsecond-pulsed electric fields (μsPEFs) can effectively ablate hepatocellular carcinomas in animal models. This preclinical study evaluates the feasibility and safety of IRE on porcine livers. Altogether, 10 pigs were included. Computed tomography (CT) was used to guide two-needle electrodes that were inserted near the hilus hepatis and gall bladder. Animals were followed-up at 2 hours and at 2, 7 and 14 days post-treatment. During and after μsPEF ablation, electrocardiographs found no cardiovascular events, and contrast CT found no portal vein thrombosis. There was necrosis in the ablation zone. Mild cystic oedema around the gall bladder was found 2 hours post-treatment. Pathological studies showed extensive cell death. There was no large vessel damage, but there was mild endothelial damage in some small vessels. Follow-up liver function tests and routine blood tests showed immediate liver function damage and recovery from the damage, which correlated to the pathological changes. These results indicate that μsPEF ablation affects liver tissue and is less effective in vessels, which enable μsPEFs to ablate central tumour lesions close to the hilus hepatis and near large vessels and bile ducts, removing some of the limitations and contraindications of conventional thermal ablation.
Targeted cellular ablation based on the morphology of malignant cells
Ivey, Jill W.; Latouche, Eduardo L.; Sano, Michael B.; Rossmeisl, John H.; Davalos, Rafael V.; Verbridge, Scott S.
2015-01-01
Treatment of glioblastoma multiforme (GBM) is especially challenging due to a shortage of methods to preferentially target diffuse infiltrative cells, and therapy-resistant glioma stem cell populations. Here we report a physical treatment method based on electrical disruption of cells, whose action depends strongly on cellular morphology. Interestingly, numerical modeling suggests that while outer lipid bilayer disruption induced by long pulses (~100 μs) is enhanced for larger cells, short pulses (~1 μs) preferentially result in high fields within the cell interior, which scale in magnitude with nucleus size. Because enlarged nuclei represent a reliable indicator of malignancy, this suggested a means of preferentially targeting malignant cells. While we demonstrate killing of both normal and malignant cells using pulsed electric fields (PEFs) to treat spontaneous canine GBM, we proposed that properly tuned PEFs might provide targeted ablation based on nuclear size. Using 3D hydrogel models of normal and malignant brain tissues, which permit high-resolution interrogation during treatment testing, we confirmed that PEFs could be tuned to preferentially kill cancerous cells. Finally, we estimated the nuclear envelope electric potential disruption needed for cell death from PEFs. Our results may be useful in safely targeting the therapy-resistant cell niches that cause recurrence of GBM tumors. PMID:26596248
Antioxidant and Nephroprotective Activities of the Extract and Fractions of Homonoia riparia Lour.
Xavier, Seena Kanniparambil; Haneefa, Shoja Muhammed; Anand, Devkar Raviraj; Polo, Picheswara Rao; Maheshwari, Rajalekshmi; Shreedhara, Chandrashekara Shastry; Setty, Manganahalli Manjunath
2017-01-01
Homonoia riparia is a plant, which is widely used in the indigenous system of medicine for the treatment of urolithiasis, renal disorders and inflammatory conditions. This is the first report on the antioxidant and nephroprotective activities of whole plant of H. riparia . The present study aims at investigating the in vitro antioxidant and nephroprotective activity of the methanol extract and its different fractions of H. riparia . Petroleum ether (HRPE), Ethyl acetate (HREA), Butanol (HRBU), aqueous fractions (HRAQ) were prepared from the crude methanol extract of H. riparia (HRM) using liquid partitioning. Total phenolic content, flavonoid content and antioxidant activity assay were performed according to suitable methods. Nephroprotective activities were evaluated by MTT assay using Human Embryonic Kidney cells against cisplatin induced toxicity. Quantification of gallic acid was performed using validated HPTLC method. The studies showed that extract and fractions possess significant nephroprotective activity against cisplatin induced renal toxicity. All the extracts/fractions of whole plant of Homonoia riparia was found to be significantly reducing cisplatin induced toxicity (< 0.05). The highest activity was observed with HRBU and HRAQ with a percentage viability of 293.09 ± 4.3 and 345.07 ± 3.2 at a concentration of 200 µg/ml. Gallic acid was detected in the HRM/fractions using HPTLC. Cisplatin (8 μg/ml) exhibited 50 % inhibition in cell viability in HEK 293 cellsButanol and aqueous fractions of Homonoia riparia showed significant nephroprotective activity against cisplatin induced cell damage in HEK cells.Gallic acid was detected and quantified in the extract and fractions of whole plant of Homonoia riparia Abbreviations used: HPTLC: High Performance Thin Layer Chromatography, DPPH: 1,1-diphenyl-2-picrylhydrazyl, ABTS: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, MTT: 3-(4,5-dimethylthiazolyl-2-yl)-2,5- diphenyl tetrazolium bromide, GAE: Gallic acid equivalents, QE: Quercetin equivalents, HEK: Human Embryonic Kidney, HRM: Methanol extract of H. riparia, HRPE: Petroleum ether fraction of H. riparia, HREA: ethyl acetate fraction of H. riparia, HRBU: Butanol fraction of H. riparia, HRAQ: Aqueous fraction of H. riparia, DMEM: Dulbecco's minimum essential medium, FBS: Foetal bovine serum, DMSO: Dimethyl sulfoxide, ANOVA: One way analysis of variance.
Rodrigo, D; Barbosa-Cánovas, G V; Martínez, A; Rodrigo, M
2003-12-01
The effects of pulsed electric fields (PEFs) on pectin methyl esterase (PME), molds and yeast, and total flora in fresh (nonpasteurized) mixed orange and carrot juice were studied. The PEF effect was more extensive when juices with high levels of initial PME activity were subjected to treatment and when PEF treatment (at 25 kV/cm for 340 micros) was combined with a moderate temperature (63 degrees C), with the maximum level of PME inactivation being 81.4%. These conditions produced 3.7 decimal reductions in molds and yeast and 2.4 decimal reductions in total flora. Experimental inactivation data for PME, molds and yeast, and total flora were fitted to Bigelow, Hülsheger, and Weibull inactivation models by nonlinear regression. The best fit (lowest mean square error) was obtained with the Weibull model.
Improving mass transfer to soften tissues by pulsed electric fields: fundamentals and applications.
Puértolas, E; Luengo, E; Álvarez, I; Raso, J
2012-01-01
The mass transfer phenomenon occurs in many operations of the food industry with the purpose of obtaining a given substance of interest, removing water from foods, or introducing a given substance into the food matrix. Pretreatments that modify the permeability of the cell membranes, such as grinding, heating, or enzymatic treatment, enhance the mass transfer. However, these techniques may require a significant amount of energy and can cause losses of valuable food compounds. Pulsed electric field (PEF) technology is a nonthermal processing method that causes permeabilization of cell membranes using low energy requirements and minimizing quality deterioration of the food compounds. Many practical applications of PEF for enhancing mass transfer in the food industry have been investigated. The purpose of this chapter is to give an overview of the state of the art of application of PEF for improving mass transfer in the food industry.
Fractionation of radioactivity in the milk of goats administered UC-aflatoxin B1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goto, T.; Hsieh, D.P.
A detailed fractionation of radioactivity in the milk of goats administered UC-aflatoxin B1 at low doses was performed. The milk collected in the first 24 h following dosing contained radioactivity equivalent to 0.45-1.1% of the dose given. The radioactivity in each sample was partitioned into 4 fractions: ether, protein, dichloromethane, and water-alcohol. Over 80% of the radioactivity was detected in the dichloromethane fraction, of which over 95% was attributable to aflatoxin M1. No aflatoxin B1 or other known aflatoxin metabolites were detected in any fraction. The results indicate that the major metabolite of aflatoxin B1 in goat milk is aflatoxinmore » M1 and that other metabolites, including conjugates, are of minor significance.« less
Timmermans, R A H; Nederhoff, A L; Nierop Groot, M N; van Boekel, M A J S; Mastwijk, H C
2016-08-02
Pulsed electrical field (PEF) technology offers an alternative to thermal pasteurisation of high-acid fruit juices, by extending the shelf life of food products, while retaining its fresh taste and nutritional value. Substantial research has been performed on the effect of electrical field strength on the inactivation kinetics of spoilage and pathogenic micro-organisms and on the outgrowth of spoilage micro-organisms during shelf life. However, studies on the effect of electrical field strength on the inactivation and outgrowth of surviving populations during shelf life are missing. In this study, we assessed the influence of electrical field strength applied by PEF processing and storage temperature on the outgrowth of surviving yeast and mould populations naturally present in fresh fruit smoothie in time. Therefore, an apple-strawberry-banana smoothie was treated in a continuous-flow PEF system (130L/h), using similar inlet and outlet conditions (preheating temperature 41°C, maximum temperature 58°C) to assure that the amount of energy across the different conditions was kept constant. Smoothies treated with variable electrical field strengths (13.5, 17.0, 20.0 and 24.0kV/cm) were compared to smoothies without treatment for outgrowth of yeasts and moulds. Outgrowth of yeasts and moulds stored at 4°C and 7°C was analysed by plating and visual observation and yeast growth was modelled using the modified logistic growth model (Zwietering model). Results showed that the intensity of the electrical field strength had an influence on the degree of inactivation of yeast cells, resulting in a faster outgrowth over time at lower electrical field strength. Outgrowth of moulds over time was not affected by the intensity of the electrical field strength used. Application of PEF introduces a trade-off between type of spoilage: in untreated smoothie yeasts lead to spoilage after 8days when stored at 4 or 7°C, whereas in PEF treated smoothie yeasts were (partly) inactivated and provided outgrowth opportunities for moulds, which led to spoilage by moulds after 14days (7°C) or 18days (4°C). Copyright © 2016 Elsevier B.V. All rights reserved.
Sterilization of liquid foods by pulsed electric fields–an innovative ultra-high temperature process
Reineke, Kai; Schottroff, Felix; Meneses, Nicolas; Knorr, Dietrich
2015-01-01
The intention of this study was to investigate the inactivation of endospores by a combined thermal and pulsed electric field (PEF) treatment. Therefore, self-cultivated spores of Bacillus subtilis and commercial Geobacillus stearothermophilus spores with certified heat resistance were utilized. Spores of both strains were suspended in saline water (5.3 mS cm−1), skim milk (0.3% fat; 5.3 mS cm−1) and fresh prepared carrot juice (7.73 mS cm−1). The combination of moderate preheating (70–90°C) and an insulated PEF-chamber, combined with a holding tube (65 cm) and a heat exchanger for cooling, enabled a rapid heat up to 105–140°C (measured above the PEF chamber) within 92.2–368.9 μs. To compare the PEF process with a pure thermal inactivation, each spore suspension was heat treated in thin glass capillaries and D-values from 90 to 130°C and its corresponding z-values were calculated. For a comparison of the inactivation data, F-values for the temperature fields of both processes were calculated by using computational fluid dynamics (CFD). A preheating of saline water to 70°C with a flow rate of 5 l h−1, a frequency of 150 Hz and an energy input of 226.5 kJ kg−1, resulted in a measured outlet temperature of 117°C and a 4.67 log10 inactivation of B. subtilis. The thermal process with identical F-value caused only a 3.71 log10 inactivation. This synergism of moderate preheating and PEF was even more pronounced for G. stearothermophilus spores in saline water. A preheating to 95°C and an energy input of 144 kJ kg−1 resulted in an outlet temperature of 126°C and a 3.28 log10 inactivation, whereas nearly no inactivation (0.2 log10) was achieved during the thermal treatment. Hence, the PEF technology was evaluated as an alternative ultra-high temperature process. However, for an industrial scale application of this process for sterilization, optimization of the treatment chamber design is needed to reduce the occurring inhomogeneous temperature fields. PMID:25999930
Bermúdez-Aguirre, Daniela; Fernández, Sulmer; Esquivel, Heracleo; Dunne, Patrick C; Barbosa-Cánovas, Gustavo V
2011-01-01
Pulsed electric fields (PEF) technology was used to pasteurize raw milk under selected treatments. Processing conditions were: temperature 20, 30, and 40 °C, electric field 30.76 to 53.84 kV/cm, and pulse numbers 12, 24, and 30 for skim milk (SM), and 12, 21, and 30 for whole milk (WM) (2 μs pulse width, monopolar). Physicochemical parameters (pH, electrical conductivity, density, color, solids nonfat [SNF]) and composition (protein and fat content) were measured after processing. Shelf life of SM and WM was assessed after processing at 46.15 kV/cm, combined with temperature (20 to 60 °C) and 30 pulses. Mesophilic and psychrophilic loads and pH were evaluated during storage at 4 and 21 °C. Results showed minor variations in physicochemical properties after processing. There was an interesting trend in SM in SNF, which decreased as treatment became stronger; similar behavior was observed for fat and protein, showing a 0.18% and 0.17% decrease, respectively, under the strongest conditions. Protein and fat content decreased in WM samples treated at 40 °C, showing a decrease in protein (0.11%), and an even higher decrease in fat content. During storage, PEF-treated milk samples showed higher stability at 4 °C with minor variations in pH; after 33 d, pH was higher than 6. However samples at 21 °C showed faster spoilage and pH dropped to 4 after 5 d. Growth of mesophilic bacteria was delayed in both milks after PEF processing, showing a 6- and 7-log cycles for SM and WM, respectively, after day 25 (4 °C); however, psychrophilic bacteria grew faster in both cases. Pulsed electric fields (PEF) technology in the pasteurization of liquid food products has shown positive results. Processing times can be reduced considerably, which in turn reduces the loss of nutrients and offers important savings in energy. PEF has been used successfully to pasteurize some liquid foods, but it is still not used commercially in milk pasteurization, although several trials have shown the positive effects of PEF milk pasteurization, which could allow for its future use at the industrial level. © 2011 Institute of Food Technologists®
Momordica charantia constituents and antidiabetic screening of the isolated major compounds.
Harinantenaina, Liva; Tanaka, Michi; Takaoka, Shigeru; Oda, Munehiro; Mogami, Orie; Uchida, Masayuki; Asakawa, Yoshinori
2006-07-01
Bioguided fractionation of the methanol extract of Momordica charantia dried gourds led to the isolation of three new cucurbitane triterpenoids (1-3), together with eight known compounds (4-11). The aglycone of momordicoside I was isolated from the ether soluble fraction in a high amount. The structures of the metabolites were established on the basis of one and two dimensional NMR spectroscopic evidence, X-ray analysis, and comparison with the reported data in the literature. A number of phytochemicals have been isolated from Momordica charantia but the constituents responsible for the hypoglycaemic/antihyperglycaemic activities have not been determined. Therefore, in order to evaluate the contribution of the cucurbitane triterpenoids of the ether fraction of M. charantia methanol extract to in vivo anti-diabetic effects, the major compounds, 5beta,19-epoxy-3beta,25-dihydroxycucurbita-6,23(E)-diene (4), and 3beta,7beta,25-trihydroxycucurbita-5,23(E)-dien-19-al (5) have been tested and have shown blood hypoglycaemic effects in the diabetes-induced male ddY mice strain at 400 mg/kg. The two aglycones of charantin did not show any hypoglycaemic effects. Our finding is the first demonstration that major pure cucurbutanoid compounds of M. charantia have in vivo hypoglycaemic effects.
Endocannabinoid signaling in hypothalamic circuits regulates arousal from general anesthesia in mice
Zhong, Haixing; Tong, Li; Gu, Ning; Gao, Fang; Lu, Yacheng; Liu, Jingjing; Li, Xin; Bergeron, Richard; Pomeranz, Lisa E.; Wang, Feng; Luo, Chun-Xia; Ren, Yan; Wu, Sheng-Xi; Xie, Zhongcong; Xu, Lin; Li, Jinlian; Dong, Hailong; Xiong, Lize
2017-01-01
Consciousness can be defined by two major attributes: awareness of environment and self, and arousal, which reflects the level of awareness. The return of arousal after general anesthesia presents an experimental tool for probing the neural mechanisms that control consciousness. Here we have identified that systemic or intracerebral injection of the cannabinoid CB1 receptor (CB1R) antagonist AM281 into the dorsomedial nucleus of the hypothalamus (DMH) — but not the adjacent perifornical area (Pef) or the ventrolateral preoptic nucleus of the hypothalamus (VLPO) — accelerates arousal in mice recovering from general anesthesia. Anesthetics selectively activated endocannabinoid (eCB) signaling at DMH glutamatergic but not GABAergic synapses, leading to suppression of both glutamatergic DMH-Pef and GABAergic DMH-VLPO projections. Deletion of CB1R from widespread cerebral cortical or prefrontal cortical (PFC) glutamatergic neurons, including those innervating the DMH, mimicked the arousal-accelerating effects of AM281. In contrast, CB1R deletion from brain GABAergic neurons or hypothalamic glutamatergic neurons did not affect recovery time from anesthesia. Inactivation of PFC-DMH, DMH-VLPO, or DMH-Pef projections blocked AM281-accelerated arousal, whereas activation of these projections mimicked the effects of AM281. We propose that decreased eCB signaling at glutamatergic terminals of the PFC-DMH projection accelerates arousal from general anesthesia through enhancement of the excitatory DMH-Pef projection, the inhibitory DMH-VLPO projection, or both. PMID:28463228
Nanosecond pulsed electric field thresholds for nanopore formation in neural cells
NASA Astrophysics Data System (ADS)
Roth, Caleb C.; Tolstykh, Gleb P.; Payne, Jason A.; Kuipers, Marjorie A.; Thompson, Gary L.; DeSilva, Mauris N.; Ibey, Bennett L.
2013-03-01
The persistent influx of ions through nanopores created upon cellular exposure to nanosecond pulse electric fields (nsPEF) could be used to modulate neuronal function. One ion, calcium (Ca), is important to action potential firing and regulates many ion channels. However, uncontrolled hyper-excitability of neurons leads to Ca overload and neurodegeneration. Thus, to prevent unintended consequences of nsPEF-induced neural stimulation, knowledge of optimum exposure parameters is required. We determined the relationship between nsPEF exposure parameters (pulse width and amplitude) and nanopore formation in two cell types: rodent neuroblastoma (NG108) and mouse primary hippocampal neurons (PHN). We identified thresholds for nanoporation using Annexin V and FM1-43, to detect changes in membrane asymmetry, and through Ca influx using Calcium Green. The ED50 for a single 600 ns pulse, necessary to cause uptake of extracellular Ca, was 1.76 kV/cm for NG108 and 0.84 kV/cm for PHN. At 16.2 kV/cm, the ED50 for pulse width was 95 ns for both cell lines. Cadmium, a nonspecific Ca channel blocker, failed to prevent Ca uptake suggesting that observed influx is likely due to nanoporation. These data demonstrate that moderate amplitude single nsPEF exposures result in rapid Ca influx that may be capable of controllably modulating neurological function.
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Kitano, Hiroya; Saito, Rumiko; Kimura, Yutaka; Aiba, Setsuya; Oshimura, Mitsuo; Shimizu, Eiji
2015-11-09
This study aimed to investigate the effects of particulate matter (PM) on pulmonary function in schoolchildren, as well as the relationships of these effects with interleukin-8. Morning peak expiratory flow (PEF) was measured daily in 399 children during April-May 2012, and in 384 of these children during March-May 2013. PEF's association with the daily levels of suspended particulate matter (SPM) and PM < 2.5 mm (PM2.5) was estimated using a linear mixed model. Interleukin-8 promoter activity was assessed in THP-G8 cells stimulated by fallen PM collected at Tottori University Hospital during four periods (two in 2012 and two in 2013). An increase of 14.0 mg/m³ in SPM led to PEF changes of -2.16 L/min in 2012 and -0.81 L/min in 2013, respectively. An increment of 10.7 mg/m³ in PM2.5 was associated with PEF changes of -2.58 L/min in 2012 and -0.55 L/min in 2013, respectively. These associations were only significant in 2012. Interleukin-8 promoter activity was significantly higher in both periods of 2012 than in 2013. There was a significant association between pulmonary function in schoolchildren and daily levels of SPM and PM2.5, but this association may differ depending on the PM's ability to elicit interleukin-8 production.
Sharma, Pankaj; Oey, Indrawati; Everett, David W
2016-09-15
Thermodynamics of milk components (milk fat, xanthine oxidase, caseins and whey proteins) in pulsed electric field (PEF)-treated milk were compared with thermally treated milk (63 °C for 30 min and 73 °C for 15s). PEF treatments were applied at 20 or 26 kV cm(-1) for 34 μs with or without pre-heating of milk (55 °C for 24s), using bipolar square wave pulses in a continuous mode of operation. PEF treatments did not affect the final temperatures of fat melting (Tmelting) or xanthine oxidase denaturation (Tdenaturation), whereas thermal treatments increased both the Tmelting of milk fat and the Tdenaturation for xanthine oxidase by 2-3 °C. Xanthine oxidase denaturation was ∼13% less after PEF treatments compared with the thermal treatments. The enthalpy change (ΔH of denaturation) of whey proteins decreased in the treated-milk, and denaturation increased with the treatment intensity. New endothermic peaks in the calorimetric thermograms of treated milk revealed the formation of complexes due to interactions between MFGM (milk fat globule membrane) proteins and skim milk proteins. Evidence for the adsorption of complexes onto the MFGM surface was obtained from the increase in surface hydrophobicity of proteins, revealing the presence of unfolded hydrophobic regions. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Werhahn, Jasper C.; Akase, Dai; Xantheas, Sotiris S.
2014-08-14
The scaled versions of the newly introduced [S. S. Xantheas and J. C. Werhahn, J. Chem. Phys.141, 064117 (2014)] generalized forms of some popular potential energy functions (PEFs) describing intermolecular interactions – Mie, Lennard-Jones, Morse, and Buckingham exponential-6 – have been used to fit the ab initio relaxed approach paths and fixed approach paths for the halide-water, X -(H 2O), X = F, Cl, Br, I, and alkali metal-water, M +(H 2O), M = Li, Na, K, Rb, Cs, interactions. The generalized forms of those PEFs have an additional parameter with respect to the original forms and produce fits tomore » the ab initio data that are between one and two orders of magnitude better in the χ 2 than the original PEFs. They were found to describe both the long-range, minimum and repulsive wall of the respective potential energy surfaces quite accurately. Overall the 4-parameter extended Morse (eM) and generalized Buckingham exponential-6 (gBe-6) potentials were found to best fit the ab initio data for these two classes of ion-water interactions. Finally, the fitted values of the parameter of the (eM) and (gBe-6) PEFs that control the repulsive wall of the potential correlate remarkably well with the ionic radii of the halide and alkali metal ions.« less
[Study on Chemical Constituents of Petroleum Ether Fraction from Rubus alceaefolius].
Chen, Pan; Fang, Zhi-jian; Yan, Han-jing; Zhou, Hong-bo; Mei, Quan-xi
2015-01-01
To investigate the chemical constituents of Rubus alceaefolius. Nine compounds were isolated and purified from the petroleum ether extract of 95% alcohol extract of Rubus alceaefolius by repeated column chromatography on silica, Sephadex LH-20 and structurally identified by spectral analysis. The compounds were identified as chrysophanol(1), physcion (2), β-sitosterol(3), 3-oxotirucalla-7, 24-dien-21-oic acid(4), myricadiol(5), 19-α-hydroxy-3-acetyl-ursolic acid(6), N-benzoylphenylalaninyl-N-benzoylphenylalaninate(7), aurantiamide acetate(8) and euscaphic acid(9). Compounds land 4~8 are isolated from this plant for the first time, and compounds 4 - 8 are found in plants of Rubus genus for the first time.
Pyrrolidone - a new solvent for the methylation of humic acid
Wershaw, R. L.; Pinckney, D.J.; Booker, S.E.
1975-01-01
In the past, humic acid has been methylated by suspending it in a solution of diazomethane in diethyl ether, and degrading the partly methylated humic acid to release those parts of the molecule that were methylated. Only small fragments of the molecule have been identified by this technique. In the procedure described here the humic acid is dissolved in 2-pyrrolidone and methylated by the addition of diazomethane in diethyl ether and ethanol to the solution. Because the humic acid is completely dissolved in the reaction medium, disaggregation of the humic acid particles takes place and much more complete methylation is obtained. The methylated products may be fractionated by countercurrent distribution and analyzed by mass spectrometry.
Hammann, Simon; Conrad, Jürgen; Vetter, Walter
2015-06-12
Countercurrent chromatography (CCC) is a technique, which uses two immiscible liquid phases for a separation process in a long and hollow tube. The technique allows the separation of high amounts of sample (50mg to several grams) with a low consumption of solvents. In this study, we fractionated 50mg technical octabromodiphenyl ether (DE-79) and analyzed the fractions by gas chromatography with mass spectrometry (GC/MS) and proton nuclear magnetic resonance ((1)H NMR) spectroscopy. CCC separations were performed with n-hexane/acetonitrile as solvent system in tail-to-head (i.e. the upper phase is mobile) mode. Twelve CCC fractions were studied for the PBDE composition. CCC elution of PBDE congeners was dependent both on the degree of bromination and substitution pattern. Higher brominated congeners eluted faster than lower brominated congeners and isomers with vicinal hydrogen atoms eluted last. In addition to several known PBDE congeners in DE-79, we were able to unequivocally identify BDE 195 in DE-79 and we could verify the presence of BDE 184. Finally, we also established the online hyphenation of CCC with (1)H NMR. The use of deuterated solvents could be avoided by using n-hexane/acetonitrile as two-phase system. By online CCC-(1)H NMR in stop-flow mode we were able to detect eight PBDE congeners in the mixture. Copyright © 2015 Elsevier B.V. All rights reserved.
Kriegeskorte, Nikolaus
2012-01-01
The two major functions of a scientific publishing system are to provide access to and evaluation of scientific papers. While open access (OA) is becoming a reality, open evaluation (OE), the other side of the coin, has received less attention. Evaluation steers the attention of the scientific community and thus the very course of science. It also influences the use of scientific findings in public policy. The current system of scientific publishing provides only journal prestige as an indication of the quality of new papers and relies on a non-transparent and noisy pre-publication peer-review process, which delays publication by many months on average. Here I propose an OE system, in which papers are evaluated post-publication in an ongoing fashion by means of open peer review and rating. Through signed ratings and reviews, scientists steer the attention of their field and build their reputation. Reviewers are motivated to be objective, because low-quality or self-serving signed evaluations will negatively impact their reputation. A core feature of this proposal is a division of powers between the accumulation of evaluative evidence and the analysis of this evidence by paper evaluation functions (PEFs). PEFs can be freely defined by individuals or groups (e.g., scientific societies) and provide a plurality of perspectives on the scientific literature. Simple PEFs will use averages of ratings, weighting reviewers (e.g., by H-index), and rating scales (e.g., by relevance to a decision process) in different ways. Complex PEFs will use advanced statistical techniques to infer the quality of a paper. Papers with initially promising ratings will be more deeply evaluated. The continual refinement of PEFs in response to attempts by individuals to influence evaluations in their own favor will make the system ungameable. OA and OE together have the power to revolutionize scientific publishing and usher in a new culture of transparency, constructive criticism, and collaboration. PMID:23087639
Garcia, Paulo A.; Davalos, Rafael V.; Miklavcic, Damijan
2014-01-01
Electroporation-based therapies are powerful biotechnological tools for enhancing the delivery of exogeneous agents or killing tissue with pulsed electric fields (PEFs). Electrochemotherapy (ECT) and gene therapy based on gene electrotransfer (EGT) both use reversible electroporation to deliver chemotherapeutics or plasmid DNA into cells, respectively. In both ECT and EGT, the goal is to permeabilize the cell membrane while maintaining high cell viability in order to facilitate drug or gene transport into the cell cytoplasm and induce a therapeutic response. Irreversible electroporation (IRE) results in cell kill due to exposure to PEFs without drugs and is under clinical evaluation for treating otherwise unresectable tumors. These PEF therapies rely mainly on the electric field distributions and do not require changes in tissue temperature for their effectiveness. However, in immediate vicinity of the electrodes the treatment may results in cell kill due to thermal damage because of the inhomogeneous electric field distribution and high current density during the electroporation-based therapies. Therefore, the main objective of this numerical study is to evaluate the influence of pulse number and electrical conductivity in the predicted cell kill zone due to irreversible electroporation and thermal damage. Specifically, we simulated a typical IRE protocol that employs ninety 100-µs PEFs. Our results confirm that it is possible to achieve predominant cell kill due to electroporation if the PEF parameters are chosen carefully. However, if either the pulse number and/or the tissue conductivity are too high, there is also potential to achieve cell kill due to thermal damage in the immediate vicinity of the electrodes. Therefore, it is critical for physicians to be mindful of placement of electrodes with respect to critical tissue structures and treatment parameters in order to maintain the non-thermal benefits of electroporation and prevent unnecessary damage to surrounding healthy tissue, critical vascular structures, and/or adjacent organs. PMID:25115970
Sánchez-Moreno, Concepción; Plaza, Lucía; Elez-Martínez, Pedro; De Ancos, Begoña; Martín-Belloso, Olga; Cano, M Pilar
2005-06-01
Bioactive compounds (vitamin C, carotenoids, and flavanones) and DPPH* radical scavenging capacity (RSC) were measured in orange juice (OJ) subjected to different technologies. High pressure (HP) (400 MPa/40 degrees C/1 min), pulsed electric fields (PEF) (35 kVcm(-1)/750 micros), low pasteurization (LPT) (70 degrees C/30 s), high pasteurization (HPT) (90 degrees C/1 min), HPT plus freezing (HPT+F) (-38 degrees C/15 min), and freezing (F) were studied. Among the treatments assayed, even though the losses in total vitamin C were < 9%, treatments with the higher temperatures tended to show the higher decrease in the content of both forms of vitamin C. HP treatment led to an increased (P < 0.05) carotenoid release (53.88%) and vitamin A value (38.74%). PEF treatment did not modify individual or total carotenoids content. Traditional thermal treatments did not exert any effect on total carotenoid content or vitamin A value. With regard to individual carotenoid extraction, HPT and HPT+F led to different releases of carotenoids. With respect to flavanones, HP treatment led to increased (P < 0.05) naringenin (20.16%) and hesperetin (39.88%) contents, whereas PEF treatment did not modify flavanone content. In general, pasteurization and freezing process led to a diminished (P < 0.05) naringenin content (16.04%), with no modification in hesperetin. HP and PEF treatments did not modify DPPH* RSC. In the case of traditional thermal technologies, HPT treatment showed a decrease (P < 0.05) in RSC (6.56%), whereas LPT, HPT+F, and F treatments did not modify RSC. Vitamin C modulated RSC, in terms of antioxidant concentration (EC50) and kinetics (AE = 1/EC50TEC50), in the treated and untreated OJ. In summary, HP and PEF technologies were more effective than HPT treatment in preserving bioactive compounds and RSC of freshly squeezed orange juice.
Antidiabetic activity of aqueous extract and non polysaccharide fraction of Cynodon dactylon Pers.
Jarald, E E; Joshi, S B; Jain, D C
2008-09-01
Petroleum ether (60 degrees-80 degrees C), chloroform, acetone, ethanol, aqueous and crude hot water extracts of the whole plant of C. dactylon and the two fractions of aqueous extract were tested for antihyperglycaemic activity in glucose overloaded hyperglycemic rats and in alloxan induced diabetic model at two-dose levels, 200 and 400 mg/kg (po) respectively. The aqueous extract of C. dactylon and the non polysaccharide fraction of aqueous extract were found to exhibit significant antihyperglycaemic activity and only the non polysaccharide fraction was found to produce hypoglycemia in fasted normal rats. Treatment of diabetic rats with aqueous extract and non polysaccharide fraction of the plant decreased the elevated biochemical parameters, glucose, urea, creatinine, serum cholesterol, serum triglyceride, high density lipoprotein, low density lipoprotein, haemoglobin and glycosylated haemoglobin significantly. Comparatively, the non polysaccharide fraction of aqueous extract was found to be more effective than the aqueous extract.
Contact sex pheromone components of the cowpea weevil, Callosobruchus maculatus.
Nojima, Satoshi; Shimomura, Kenji; Honda, Hiroshi; Yamamoto, Izuru; Ohsawa, Kanju
2007-05-01
The cowpea weevil, Callosobruchus maculatus, is a major pest of stored pulses. Females of this species produce a contact sex pheromone that elicits copulation behavior in males. Pheromone was extracted from filter-paper shelters taken from cages that housed females. Crude ether extract stimulated copulation in male C. maculatus. Initial fractionation showed behavioral activity in acidic and neutral fractions. Furthermore, bioassay-guided fractionation and gas chromatography-mass spectroscopy (GC-MS) analysis of active fractions revealed that the active components of the acidic fraction were 2,6-dimethyloctane-1,8-dioic acid and nonanedioic acid. These components along with the hydrocarbon fraction, a mixture of C(27)-C(35) straight chain and methyl branched hydrocarbons, had a synergistic effect on the behavior of males. Glass dummies treated with an authentic pheromone blend induced copulation behavior in males. The potential roles of the contact sex pheromone of C. maculatus are discussed.
Triacetin as food additive in gummy candy and other foodstuffs on the market.
Ogawa, T; Moriwaki, N; Fujii, R; Tanaka, K; Mori, E; Saitou, M; Yoshizawa, H; Sakaguchi, H
1992-04-01
The qualitative and quantitative analytical methods were proposed for the simple and rapid determination of triacetin (TAc) in commercial gummy candies and other foodstuffs by gas chromatography (GC), thin layer chromatography (TLC) and infrared spectroscopy (IR). Each extract from the samples was obtained by pretreatment of the foodstuffs as follows: (A) Gummy candy was dissolved in warm water and the solution was extracted with chloroform. The organic (chloroform) layer was separated. (B) Samples (such as ice cream) containing substantial water were mixed with anhydrous Na2SO4 and stirred to sandy appearance and dried. The residue was homogenized with ether, followed by centrifuging, and the organic (ether) layer was separated. (C) Dried samples (such as chocolate and cookie) were smashed, homogenized with ether, and followed by centrifuging, and the organic (ether) layer was separated. (D) Candy was dissolved in warm water and the solution was extracted with ether. The organic (ether) layer was separated. Each organic layer from (A)-(D) was washed with 10% NaHCO3 and evaporated. The residue containing TAc was dissolved in dichloromethane. The extract obtained was subjected to column chromatography on silica gel. The fractions containing TAc were employed in GC with 25% PEG-20M column, TLC, and IR analyses. Recovery of TAc from gummy candy was 99.1 +/- 3.0% and those from other foodstuffs ranged from was 82.1 to 99.4% by GC. Detection limit by this method was 10 ppm. TAc was found to contain at a level as high as 550 ppm in one domestic gummy candy. On the other hand, one imported gummy candy contained no more than 20 ppm of TAc gummy candy.
Environment Partitioning and Reactivity of Polybrominated Diphenylethers
NASA Technical Reports Server (NTRS)
Hua, Inez; Iraci, Laura T.; Jafvert, Chad; Bezares-Cruz, Juan
2004-01-01
Polybrominated diphenyl ethers (PBDEs) are an important class of flame retardants. Annual global demand for these compounds was over 67,000 metric tons in 2001. PBDEs have recently been extensively investigated as environmental contaminants because they have been detected in air, sediment, and tissue samples from urban and remote areas. Important issues include quantifying PBDE partitioning in various environmental compartments, and elucidating transformation pathways. The partitioning of PBDE congeners to aerosols was estimated for 16 sites in the United States, Canada, and Mexico. The aerosol particles were PM2.5, the total suspended particle (TSP) concentration varied between 3.0 - 55.4 micro g/cubic meter, and the organic fraction ranged from 11 - 41%; these data are published values for each site. It is estimated that the largest fraction of each PBDE associated with the aerosol particles occurs in Mexico City, and the smallest fraction in Colorado Plateau. Although the organic fraction in Mexico City is about 60% of that observed in the Colorado Plateau, the TSP is larger by a factor of about 18.5, and it is the difference in TSP that strongly influences the fraction of particle-bound PBDE in this case. PBDE partitioning to PM2.5 particles also varies seasonally because of temperature variations. For the less brominated congeners the percentage that is particle-bound is relatively low, regardless of air temperature. In contrast, the heavier congeners exhibit a significant temperature dependence: as the temperature decreases (fall, winter) the percentage of PBDE that is particle-bound increases. The partitioning calculations complement experimental data indicating that decabromodiphenyl ether (DBDE) dissolved in hexane transforms very rapidly when irradiated with solar light. DBDE is the most highly brominated PBDE congener (10 bromine atoms) and occurs in the commercial formulation which is subject to the largest global demand.
Environmental Partitioning and Reactivity of Polybrominated Diphenylethers
NASA Astrophysics Data System (ADS)
Hua, I.; Iraci, L.; Jafvert, C.; Bezares-Cruz, J.
2004-05-01
Polybrominated diphenyl ethers (PBDEs) are an important class of flame retardants. Annual global demand for these compounds was over 67,000 metric tons in 2001. PBDEs have recently been extensively investigated as environmental contaminants because they have been detected in air, sediment, and tissue samples from urban and remote areas. Important issues include quantifying PBDE partitioning in various environmental compartments, and elucidating transformation pathways. The partitioning of PBDE congeners to aerosols was estimated for 16 sites in the United States, Canada, and Mexico. The aerosol particles were PM2.5, the total suspended particle (TSP) concentration varied between 3.0 - 55.4 μ g m-3, and the organic fraction ranged from 11 - 41%; these data are published values for each site. It is estimated that the largest fraction of each PBDE associated with the aerosol particles occurs in Mexico City, and the smallest fraction in Colorado Plateau. Although the organic fraction in Mexico City is about 60% of that observed in the Colorado Plateau, the TSP is larger by a factor of about 18.5, and it is the difference in TSP that strongly influences the fraction of particle-bound PBDE in this case. PBDE partitioning to PM2.5 particles also varies seasonally because of temperature variations. For the less brominated congeners, the percentage that is particle-bound is relatively low, regardless of air temperature. In contrast, the heavier congeners exhibit a significant temperature dependence: as the temperature decreases (fall, winter) the percentage of PBDE that is particle-bound increases. The partitioning calculations complement experimental data indicating that decabromodiphenyl ether (DBDE) dissolved in hexane transforms very rapidly when irradiated with solar light. DBDE is the most highly brominated PBDE congener (10 bromine atoms) and occurs in the commercial formulation which is subject to the largest global demand.
Bhatnagar, Manisha; Sarkar, Nandan; Gandharv, Nigam; Apang, Ona; Singh, Sarman; Ghosal, Sabari
2017-08-01
The ethnic population of Arunachal Pradesh uses a number of orchids as such, or in decoction for various ailments. Three untapped orchids namely, Rhynchostylis retusa, Tropidia curculioides and Satyrium nepalense, traditionally used in tuberculosis, asthma and cold stage of malaria in folk medicine, were selected for the present study. Dried material of each plant was divided into three parts. Solvent extraction and fractionation afforded altogether 30 extracts and fractions, which were evaluated against Mycobacterium tuberculosis (H37Rv and MDR strain) for antimycobacterial activity; promastigotes and amastigotes of Leishmania donovani for leishmanicidal activity and two gram positive and three gram negative clinical isolates for antibacterial activity. The most significant antimycobacterial activity was observed with n-hexane fraction of the flower of Satyrium nepalense with MIC of 15.7 μg/mL. The most promising leishmanicidal activity was observed with diethyl ether fraction of the roots of Rhynchostylis retusa with IC 50 values of 56.04 and 18.4 μg/mL against promastigotes and intracellular amastigotes respectively. Evaluation of antibacterial activity identified S. nepalense flower n-hexane and R. retusa roots diethyl ether as potential fractions with MIC values of ≤100 μg/mL against selected clinical isolates. This is the first report of the plants possessing antimycobacterial and leishmanicidal activity. The investigation resulted in identification of S. nepalense as the most promising plant, which possessed all three activities in significant proportion. This laboratory outcome could be translated to marketable pharmaceutical products and also to produce maximum benefits to the local of nearby area. Antimycobacterial and leishmanicidal activity of medicinal orchids.
El Darra, Nada; Rajha, Hiba N; Ducasse, Marie-Agnès; Turk, Mohammad F; Grimi, Nabil; Maroun, Richard G; Louka, Nicolas; Vorobiev, Eugène
2016-12-15
This work studies the effect of pulsed electric field (PEF) treatment at moderate and high field strengths (E=0.8kV/cm & 5kV/cm) prior and during alcoholic fermentation (AF) of red grapes on improving different parameters of pre-treated extracts: pH, °Brix, colour intensity (CI), total polyphenols content (TPI) of Cabernet Sauvignon red wine. Similar trends were observed for treating grapes using moderate and high electric field strength on the enhancement of CI and TPI of the wine after AF. The application of PEF using moderate strengths at different times during cold maceration (CM) (0, 2 and 4days) was more efficient for treatment during CM. The treatment during AF showed lower extraction rate compared to treating during CM and prior to AF. Our results clearly show that the best time for applying the PEF-treatment through the red fermentation is during the CM step. Copyright © 2016. Published by Elsevier Ltd.
Zhuang, Jie; Kolb, Juergen F
2015-06-01
The dielectric spectra of fresh pig whole blood in the β-dispersion range after exposure to 300-nanosecond pulsed electric fields (nsPEFs) with amplitude higher than the supra-electroporation threshold for erythrocytes were recorded by time domain reflectometry dielectric spectroscopy. The implications of the dielectric parameters on the dynamics of post-pulse pore development were discussed in light of the Cole-Cole relaxation model. The temporal development of the Cole-Cole parameters indicates that nsPEFs induced significant poration and swelling of erythrocytes within the first 5 min. The results also show that the majority of erythrocytes could not fully recover from supra-electroporation up to 30 min. The findings of this study suggest that time domain dielectric spectroscopy is a promising label-free and real-time physiological measuring technique for nsPEF-blood related biomedical applications, capable of following the conformational and morphological changes of cells. Copyright © 2014 Elsevier B.V. All rights reserved.
Renovation of the hot press in the Plutonium Experimental Facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Congdon, J.W.; Nelson, G.H.
1990-03-05
The Plutonium Experimental Facility (PEF) will be used to develop a new fuel pellet fabrication process and to evaluate equipment upgrades. The facility was used from 1978 until 1982 to optimize the parameters for fuel pellet production using a process which was developed at Los Alamos National Laboratory. The PEF was shutdown and essentially abandoned until mid-1987 when the facility renovations were initiated by the Actinide Technology Section (ATS) of SRL. A major portion of the renovation work was related to the restart of the hot press system. This report describes the renovations and modifications which were required to restartmore » the PEF hot press. The primary purpose of documenting this work is to help provide a basis for Separations to determine the best method of renovating the hot press in the Plutonium Fuel Fabrication (PuFF) facility. This report also includes several SRL recommendations concerning the renovation and modification of the PuFF hot press. 4 refs.« less
Photosynthesis energy factory: analysis, synthesis, and demonstration. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
This quantitative assessment of the potential of a combined dry-land Energy Plantation, wood-fired power plant, and algae wastewater treatment system demonstrates the cost-effectiveness of recycling certain by-products and effluents from one subsystem to another. Designed to produce algae up to the limit of the amount of carbon in municipal wastewater, the algae pond provides a positive cash credit, resulting mainly from the wastewater treatment credit, which may be used to reduce the cost of the Photosynthesis Energy Factory (PEF)-generated electricity. The algae pond also produces fertilizer, which reduces the cost of the biomass produced on the Energy Plantation, and somemore » gas. The cost of electricity was as low as 35 mills per kilowatt-hour for a typical municipally-owned PEF consisting of a 65-MWe power plant, a 144-acre algae pond, and a 33,000-acre Energy Plantation. Using only conventional or near-term technology, the most cost-effective algae pond for a PEF is the carbon-limited secondary treatment system. This system does not recycle CO/sub 2/ from the flue gas. Analysis of the Energy Plantation subsystem at 15 sites revealed that plantations of 24,000 to 36,000 acres produce biomass at the lowest cost per ton. The following sites are recommended for more detailed evaluation as potential demonstration sites: Pensacola, Florida; Jamestown, New York; Knoxville, Tennessee; Martinsville, Virginia, and Greenwood, South Carolina. A major possible extension of the PEF concept is to include the possibility for irrigation.« less
Yamada, Shinichiro; Hashizume, Atsushi; Hijikata, Yasuhiro; Inagaki, Tomonori; Suzuki, Keisuke; Kondo, Naohide; Kawai, Kaori; Noda, Seiya; Nakanishi, Hirotaka; Banno, Haruhiko; Hirakawa, Akihiro; Koike, Haruki; Halievski, Katherine; Jordan, Cynthia L.; Katsuno, Masahisa; Sobue, Gen
2016-01-01
The aim of this study was to characterize the respiratory function profile of subjects with spinal and bulbar muscular atrophy (SBMA), and to explore the underlying pathological mechanism by comparing the clinical and biochemical indices of this disease with those of amyotrophic lateral sclerosis (ALS). We enrolled male subjects with SBMA (n = 40) and ALS (n = 25) along with 15 healthy control subjects, and assessed their respiratory function, motor function, and muscle strength. Predicted values of peak expiratory flow (%PEF) and forced vital capacity were decreased in subjects with SBMA compared with controls. In SBMA, both values were strongly correlated with the trunk subscores of the motor function tests and showed deterioration relative to disease duration. Compared with activities of daily living (ADL)-matched ALS subjects, %PEF, tongue pressure, and grip power were substantially decreased in subjects with SBMA. Both immunofluorescence and RT-PCR demonstrated a selective decrease in the expression levels of the genes encoding the myosin heavy chains specific to fast-twitch fibers in SBMA subjects. The mRNA levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha and peroxisome proliferator-activated receptor delta were up-regulated in SBMA compared with ALS and controls. In conclusion, %PEF is a disease-specific respiratory marker for the severity and progression of SBMA. Explosive muscle strength, including %PEF, was selectively affected in subjects with SBMA and was associated with activation of the mitochondrial biogenesis-related molecular pathway in skeletal muscles. PMID:28005993
Subcutaneous adrenaline versus terbutaline in the treatment of acute severe asthma.
Spiteri, M A; Millar, A B; Pavia, D; Clarke, S W
1988-01-01
Subcutaneous adrenaline and terbutaline have been compared in a double blind study of 20 patients with acute severe asthma presenting to an accident and emergency department. Ten patients received adrenaline 0.5 mg (0.5 ml) and 10 terbutaline 0.5 mg (0.5 ml) subcutaneously. Further treatment with nebulised salbutamol (5 mg), hydrocortisone (200 mg), and aminophylline (0.9 mg/kg/hour) was started 15 minutes later. All patients reported a reduction in chest tightness within three minutes of receiving both adrenaline and terbutaline and reported no adverse effects. Mean baseline values of peak expiratory flow (PEF) and forced expiratory volume in one second (FEV1) did not differ significantly between the adrenaline group (130 1 min-1 and 0.83 l) and the terbutaline group (111 1 min-1 and 0.63 l). After administration of adrenaline PEF had increased by 21% and FEV1 by 40% five minutes after the injection, and by 35% and 64% at 15 minutes. Terbutaline caused a 23% increase in PEF and a 37% increase in FEV1 at five minutes, and a 40% and 58% increase at 15 minutes. There was no significant difference in PEF, FEV1, heart rate, blood pressure, or pulsus paradoxus between the two groups at any time. Continuous electrocardiographic recording showed no abnormalities in either group. Thus in this study subcutaneous adrenaline (0.5 mg) and terbutaline (0.5 mg) produced effective rapid bronchodilatation without serious side effects. PMID:3281307
de M Correia-Deur, Joya Emilie; Claudio, Luz; Imazawa, Alice Takimoto; Eluf-Neto, Jose
2012-01-01
Background In the last 20 years, there has been an increase in the incidence of allergic respiratory diseases worldwide and exposure to air pollution has been discussed as one of the factors associated with this increase. The objective of this study was to investigate the effects of air pollution on peak expiratory flow (PEF) and FEV1 in children with and without allergic sensitization. Methods Ninety-six children were followed from April to July, 2004 with spirometry measurements. They were tested for allergic sensitization (IgE, skin prick test, eosinophilia) and asked about allergic symptoms. Air pollution, temperature and relative humidity data were available. Results Decrements in PEF were observed with previous 24-h average exposure to air pollution, as well as with 3 to 10 day average exposure and were associated mainly with PM10, NO2 and O3. in all three categories of allergic sensitization. Even though allergic sensitized children tended to present larger decrements in the PEF measurements they were not statistically different from the non-allergic sensitized. Decrements in FEV1 were observed mainly with previous 24-h average exposure and 3-day moving average. Conclusions Decrements in PEF associated with air pollution were observed in children independent from their allergic sensitization status. Their daily exposure to air pollution can be responsible for a chronic inflammatory process that might impair their lung growth and later their lung function in adulthood. PMID:22544523
Chugh, Anupam; Khanal, Dipendra; Walkling-Ribeiro, Markus; Corredig, Milena; Duizer, Lisa; Griffiths, Mansel W
2014-04-23
Non-thermal processing methods, such as pulsed electric field (PEF) and tangential-flow microfiltration (TFMF), are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST) pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF) was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF). HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk ( p ≥ 0.05) but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing ( p ≥ 0.05), but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds ( p < 0.05). The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments.
Thiam, Abdoulaye; Sirés, Ignasi; Garrido, José A; Rodríguez, Rosa M; Brillas, Enric
2015-06-15
The decolorization and mineralization of solutions containing 230 mg L(-1) of the food azo dye Allura Red AC at pH 3.0 have been studied upon treatment by electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with a stirred tank reactor containing a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode to generate H2O2. The main oxidants were hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between H2O2 and added Fe(2+). The oxidation ability increased in the sequence EO-H2O2 < EF < PEF and faster degradation was always obtained using BDD. PEF process with BDD yielded almost total mineralization following similar trends in SO4(2-), ClO4(-) and NO3(-) media, whereas in Cl(-) medium, mineralization was inhibited by the formation of recalcitrant chloroderivatives. GC-MS analysis confirmed the cleavage of the −N=N− bond with formation of two main aromatics in SO4(2-) medium and three chloroaromatics in Cl(-) solutions. The effective oxidation of final oxalic and oxamic acids by BDD along with the photolysis of Fe(III)-oxalate species by UVA light accounted for the superiority of PEF with BDD. NH4(+), NO3(-) and SO4(2-) ions were released during the mineralization. Copyright © 2015 Elsevier B.V. All rights reserved.
Obaseiki-Ebor, E E; Odukoya, K; Telikepalli, H; Mitscher, L A; Shankel, D M
1993-06-01
Organic solvent extracts of leaves of 4 common edible vegetable plants--Bryophyllum pinnatum, Dialium guincense, Ocimum gratissimum and Vernonia amygdalina--had inhibitory activity for His- to His+ reverse-mutations induced by ethyl methanesulfonate acting on Salmonella typhimurium TA100. The concentrated ethyl acetate, methanol and petroleum ether extracts were heat-stable when dissolved in dimethyl sulfoxide. The Bryophyllum ethyl acetate extract was fractionated into alkaloidal/water-soluble, acids, polar lipid and non-polar lipid fractions. The polar and non-polar lipid fractions inhibited reversion mutations induced by ethyl methanesulfonate acting on TA100 or TA102, and were also active against reversions induced by 4-nitro-O-phenylenediamine and 2-aminofluorene in TA98. The alkaloidal/water-soluble and the acid fractions had no appreciable antimutagenic activities.
Dumesic, James A.; Martin Alonso, David; Luterbacher, Jeremy Scott
2016-06-07
Described is a method of processing biomass to separate it into a liquid fraction enriched in solubilized C5-sugar-containing oligomers and C-5 sugar monomers and a solid fraction enriched in substantially insoluble cellulose and C6-sugar-containing oligomers. The method includes the steps of reacting biomass with a solvent system comprising water, at least one lactone, or at least one furan, or at least one cyclic ether, and at least one acid, for a time and at a temperature to yield the liquid and solid fractions. The liquid and solid fractions may then be separated. Gamma-valeroloactone is a preferred lactone for use in the solvent system. Tetrahydrofuran is a preferred furan species for use in the solvent system.
Cheng, Ming-Ching; Lin, Li-Yun; Yu, Tung-Hsi; Peng, Robert Y
2008-06-11
Mountain celery seed essential oils (MC-E) contained 109 compounds, including mainly nine kinds of monoterpenoids, 31 kinds of of sesquiterpenoids, and 22 kinds of alcohols. A successive gel column adsorption with solvent fractionation yielded four fractionates. The pentane fractionate revealed potent hypolipidemic but poor antioxidant activities. The ether fractionate exhibited strong hypolipidemic activity in addition to excellent 1,1-diphenyl-2-picrylhydrazyl free radical- and superoxide anion-scavenging capabilities. The third acetone fractionate only showed moderate superoxide anion-scavenging activity. Finally, the fourth methanol fractionate having a rather high content of gamma-selinene, 2-methylpropanal, and Z-9-octadecenamide uniquely revealed very strong superoxide anion-scavenging capability. All MC diets except the MC-E-added diet simultaneously exhibited both significant hypolipidemic and high-density lipoprotein-cholesterol (HDL-C)-elevating capabilities. However, all diets totally failed to affect the hepatic phospholipid levels. Conclusively, the MC-E can be fractionated by such a separation technology to produce products uniquely possessing hypolipidemic and HDL-C-elevating activities.
Huang, Ai-Guo; Yi, Yang-Lei; Ling, Fei; Lu, Lin; Zhang, Qi-Zhong; Wang, Gao-Xue
2013-12-01
With the aim of finding natural anthelmintic agents against Dactylogyrus intermedius (Monogenea) in goldfish (Carassius auratus), 26 plants were screened for antiparasitic properties using in vivo anthelmintic efficacy assay. The results showed that Caesalpinia sappan, Lysima chiachristinae, Cuscuta chinensis, Artemisia argyi, and Eupatorium fortunei were found to have 100% anthelmintic efficacy at 125, 150, 225, 300, and 500 mg L(-1) after 48 h of exposure. Crude extract of the five plants were further partitioned with petroleum ether, chloroform, ethyl acetate, methanol, and water to obtain anthelmintically active fractions with various polarity. Among these fractions tested, the ethyl acetate extract of L. chiachristinae was found to be the most effective with a 50% effective concentration (EC50) value of 5.1 mg/L after 48 h of exposure. This was followed by ethyl acetate extract of C. chinensis (48 h-EC50 = 8.5 mg L(-1)), chloroform extracts of C. sappan (48 h-EC50 = 15.6 mg L(-1)), methanol extract of C. chinensis (48 h-EC50 = 15.9 mg L(-1)), and chloroform and petroleum ether extract of L. chiachristinae (EC50 values of 17.2 and 21.1 mg/L, respectively), suggesting that these plants, as well as the active fractions, provide potential sources of botanic drugs for the control of D. intermedius in aquaculture.
Osman, Samir M.; El-Haddad, Alaadin E.; El-Raey, Mohamed A.; Abd El-Khalik, Soad M.; Koheil, Mahmoud A.; Wink, Michael
2016-01-01
Background: Caesalpinia gilliesii Hook is an ornamental shrub with showy yellow flowers. It was used in folk medicine due to its contents of different classes of secondary metabolites. In our previous study, dichloromethane extract of C. gilliesii flowers showed a good antioxidant activity. Aim of the Study: Isolation and identification of bioactive hepatoprotective compounds from C. gilliesii flowers dichloromethane fraction. Materials and Methods: The hepatoprotective activity of dichloromethane fraction and isolated compounds were studied in CCl4-intoxicated rat liver slices by measuring liver injury markers (alanine aminotransferase, aspartate aminotransferase and glutathione [GSH]). All compounds were structurally elucidated on the basis of electron ionization-mass spectrometry, one- and two-dimensional nuclear magnetic resonance. Results: A new 12,13,16-trihydroxy-14(Z)-octadecenoic acid was identified in addition to the known β-sitosterol-3-O-butyl, daucosterol, isorhamnetin, isorhamnetin-3-O-rhamnoside, luteolin-7,4’-dimethyl ether, genistein-5-methyl ether, luteolin-7-O-rhamnoside, isovanillic acid, and p-methoxybenzoic acid. Dichloromethane fraction and isorhamnetin were able to significantly protect the liver against intoxication. Moreover, the dichloromethane fraction and the isolated phytosterols induced GSH above the normal level. Conclusion: The hepatoprotective activity of C. gilliesii may be attributed to its high content of phytosterols and phenolic compounds. SUMMARY Bioactive Hepatoprotective phytosterols and phenolics from chloroform extract of Caesalpinia gilliesii Abbreviations used: ALT: Alanine Aminotransferase; AST: Aspartate aminotransferase; GSH: Glutathione; SC50: Scavenging Capacity 50 (SC 50); COSY: Correlation spectroscopy; NMR: Nuclear Magnetic Resonance; CC: Column chromatography; EI-MS: Electron-impact mass spectrometry; HSQC: Heteronuclear single-quantum correlation. PMID:27563221
Jechalke, Sven; Rosell, Mònica; Martínez-Lavanchy, Paula M; Pérez-Leiva, Paola; Rohwerder, Thore; Vogt, Carsten; Richnow, Hans H
2011-02-01
Multidimensional compound-specific stable isotope analysis (CSIA) was applied in combination with RNA-based molecular tools to characterize methyl tertiary (tert-) butyl ether (MTBE) degradation mechanisms occurring in biofilms in an aerated treatment pond used for remediation of MTBE-contaminated groundwater. The main pathway for MTBE oxidation was elucidated by linking the low-level stable isotope fractionation (mean carbon isotopic enrichment factor [ε(C)] of -0.37‰ ± 0.05‰ and no significant hydrogen isotopic enrichment factor [ε(H)]) observed in microcosm experiments to expression of the ethB gene encoding a cytochrome P450 monooxygenase able to catalyze the oxidation of MTBE in biofilm samples both from the microcosms and directly from the ponds. 16S rRNA-specific primers revealed the presence of a sequence 100% identical to that of Methylibium petroleiphilum PM1, a well-characterized MTBE degrader. However, neither expression of the mdpA genes encoding the alkane hydroxylase-like enzyme responsible for MTBE oxidation in this strain nor the related MTBE isotope fractionation pattern produced by PM1 could be detected, suggesting that this enzyme was not active in this system. Additionally, observed low inverse fractionation of carbon (ε(C) of +0.11‰ ± 0.03‰) and low fractionation of hydrogen (ε(H) of -5‰ ± 1‰) in laboratory experiments simulating MTBE stripping from an open surface water body suggest that the application of CSIA in field investigations to detect biodegradation may lead to false-negative results when volatilization effects coincide with the activity of low-fractionating enzymes. As shown in this study, complementary examination of expression of specific catabolic genes can be used as additional direct evidence for microbial degradation activity and may overcome this problem.
Jechalke, Sven; Rosell, Mònica; Martínez-Lavanchy, Paula M.; Pérez-Leiva, Paola; Rohwerder, Thore; Vogt, Carsten; Richnow, Hans H.
2011-01-01
Multidimensional compound-specific stable isotope analysis (CSIA) was applied in combination with RNA-based molecular tools to characterize methyl tertiary (tert-) butyl ether (MTBE) degradation mechanisms occurring in biofilms in an aerated treatment pond used for remediation of MTBE-contaminated groundwater. The main pathway for MTBE oxidation was elucidated by linking the low-level stable isotope fractionation (mean carbon isotopic enrichment factor [ɛC] of −0.37‰ ± 0.05‰ and no significant hydrogen isotopic enrichment factor [ɛH]) observed in microcosm experiments to expression of the ethB gene encoding a cytochrome P450 monooxygenase able to catalyze the oxidation of MTBE in biofilm samples both from the microcosms and directly from the ponds. 16S rRNA-specific primers revealed the presence of a sequence 100% identical to that of Methylibium petroleiphilum PM1, a well-characterized MTBE degrader. However, neither expression of the mdpA genes encoding the alkane hydroxylase-like enzyme responsible for MTBE oxidation in this strain nor the related MTBE isotope fractionation pattern produced by PM1 could be detected, suggesting that this enzyme was not active in this system. Additionally, observed low inverse fractionation of carbon (ɛC of +0.11‰ ± 0.03‰) and low fractionation of hydrogen (ɛH of −5‰ ± 1‰) in laboratory experiments simulating MTBE stripping from an open surface water body suggest that the application of CSIA in field investigations to detect biodegradation may lead to false-negative results when volatilization effects coincide with the activity of low-fractionating enzymes. As shown in this study, complementary examination of expression of specific catabolic genes can be used as additional direct evidence for microbial degradation activity and may overcome this problem. PMID:21148686
Influence of the brewing process on furfuryl ethyl ether formation during beer aging.
Vanderhaegen, Bart; Neven, Hedwig; Verstrepen, Kevin J; Delvaux, Freddy R; Verachtert, Hubert; Derdelinckx, Guy
2004-11-03
In beer, the development of a solvent-like stale flavor is associated with the formation of furfuryl ethyl ether. The synthesis rate of this important flavor compound is proportional to the concentration of furfuryl alcohol in beer. This study shows that furfuryl alcohol in beer is mainly formed by Maillard reactions initiated during wort boiling and malt production. A mechanism for its formation from alpha-(1,4)-oligoglucans and amino acids in wort and beer is proposed. During wort boiling, a quadratic relationship was found between the wort extract concentration, on the one hand, and the increase of furfuryl alcohol and furfural, on the other. The reduction of furfural by yeast during fermentation further increases the furfuryl alcohol content. In pale beers, the furfuryl alcohol concentration is essentially determined by the thermal load on wort during brewing operations. In dark beers, a considerable fraction of furfuryl alcohol may, however, come from the dark malts used. These results lead to important practical conclusions concerning the control over furfuryl ethyl ether in beer.
Product environmental footprint of strawberries: Case studies in Estonia and Germany.
Soode-Schimonsky, Eveli; Richter, Klaus; Weber-Blaschke, Gabriele
2017-12-01
The environmental impacts of strawberries have been assessed in several studies. However, these studies either present dissimilar results or only focus on single impact categories without offering a comprehensive overview of environmental impacts. We applied the product environmental footprint (PEF) methodology to broadly indicate the environmental impacts of various strawberry production systems in Germany and Estonia by 15 impact categories. Data for the 7 case studies were gathered from two farms with organic and two farms with conventional open field production systems in Estonia and from one farm with conventional open field and one farm with a polytunnel and greenhouse production system in Germany. The greenhouse production system had the highest environmental impact with a PEF of 0.0040. In the field organic production systems, the PEF was 0.0029 and 0.0028. The field conventional production systems resulted in a PEF of 0.0008, 0.0009 and 0.0002. Polytunnel PEF was 0.0006. Human toxicity cancer effects, particulate matter and human toxicity non-cancer effects resulted in the highest impact across all analysed production systems. The main contributors were electricity for cooling, heating the greenhouse and the use of agricultural machinery including fuel burning. While production stage contributed 85% of the total impact in the greenhouse, also other life cycle stages were important contributors: pre-chain resulted in 71% and 90% of impact in conventional and polytunnels, respectively, and cooling was 47% in one organic system. Environmental impact from strawberry cooling can be reduced by more efficient use of the cooling room, increasing the strawberry yield or switching from oil shale electricity to other energy sources. Greenhouse heating is the overall impact hotspot even if it based on renewable resources. A ranking of production systems based on the environmental impact is possible only if all relevant impacts are included. Future studies should aim for detailed results across a variety of impact categories and follow product category rules in defining the life cycle stages. Copyright © 2017 Elsevier Ltd. All rights reserved.
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Ueda, Yasuto; Mikami, Masaaki; Yamamoto, Hiroyuki; Tokuyasu, Hirokazu; Kato, Kazuhiro; Konishi, Tatsuya; Tatsukawa, Toshiyuki; Shimizu, Eiji; Kitano, Hiroya
2016-01-01
Background Asian dust (AD) exposure exacerbates pulmonary dysfunction in patients with asthma. Asthma–chronic obstructive pulmonary disease overlap syndrome (ACOS), characterized by coexisting symptoms of asthma and chronic obstructive pulmonary disease, is considered a separate disease entity. Previously, we investigated the effects of AD on pulmonary function in adult patients with asthma. Here, we present the findings of our further research on the differences in the effects of AD exposure on pulmonary function between patients with asthma alone and those with ACOS. Methods Between March and May 2012, we conducted a panel study wherein we monitored daily peak expiratory flow (PEF) values in 231 adult patients with asthma. These patients were divided into 190 patients with asthma alone and 41 patients with ACOS in this study. Daily AD particle levels were measured using light detection and ranging systems. Two heavy AD days (April 23 and 24) were determined according to the Japan Meteorological Agency definition. A linear mixed model was used to estimate the association between PEF and AD exposure. Results Increments in the interquartile range of AD particles (0.018 km−1) led to PEF changes of −0.50 L/min (95% confidence interval, −0.98 to −0.02) in patients with asthma alone and −0.11 L/min (−0.11 to 0.85) in patients with ACOS. The PEF changes after exposure to heavy AD were −2.21 L/min (−4.28 to −0.15) in patients with asthma alone and −2.76 L/min (−6.86 to 1.35) in patients with ACOS. In patients with asthma alone, the highest decrease in PEF values was observed on the heavy AD day, with a subsequent gradual increase over time. Conclusion Our results suggest that the effects of AD exposure on pulmonary function differ between patients with asthma alone and ACOS, with the former exhibiting a greater likelihood of decreased pulmonary function after AD exposure. PMID:26869784
Leong, Sze Ying; Burritt, David John; Oey, Indrawati
2016-04-01
This study evaluated the health-promoting properties of Pinot Noir juices (Vitis vinifera L.) obtained at different maceration times after pulsed electric fields (PEF) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and human intestinal Caco-2 cells assays. Juice quality, anthocyanins, total phenolics and vitamin C were also determined. The evaluation of bioprotective capacity of the juice against H2O2-induced oxidative stress in Caco-2 cells was determined using biomarkers for cellular health and integrity: cell viability and lactate dehydrogenase (LDH) leakage. Compared to untreated grape juice, PEF pre-treatment on grapes enhanced the release of the major anthocyanin found in Pinot Noir, i.e. malvidin-3-O-glucoside (+224%). Increase in the content of total phenolic (+61%) and vitamin C (+19%) as well as improvement in the DPPH scavenging activity (+31%) and bioprotective capacity (+25% for cell viability and +30% for LDH leakage) were observed in grape juices following PEF treatment. Bioprotective capacity determined by the cellular biomarkers had significant linear correlations with malvidin-3-O-glucoside content (0.71⩽r⩽0.73) whereas DPPH scavenging activity was not well correlated with malvidin-3-O-glucoside (r=0.30) and total phenolics (r=0.30). Therefore, evaluation of the bioprotective capacities using Caco-2 cell assay performed in this study makes a novel contribution to the current knowledge that demonstrates the capability of PEF technology to produce plant-based foods with better phytochemical composition and exhibiting the capacity to protect cells from oxidative stress. Copyright © 2015 Elsevier Ltd. All rights reserved.
Three-photon imaging of ovarian cancer
NASA Astrophysics Data System (ADS)
Barton, Jennifer K.; Amirsolaimani, Babak; Rice, Photini; Hatch, Kenneth; Kieu, Khanh
2016-02-01
Optical imaging methods have the potential to detect ovarian cancer at an early, curable stage. Optical imaging has the disadvantage that high resolution techniques require access to the tissue of interest, but miniature endoscopes that traverse the natural orifice of the reproductive tract, or access the ovaries and fallopian tubes through a small incision in the vagina wall, can provide a minimally-invasive solution. We have imaged both rodent and human ovaries and fallopian tubes with a variety of endoscope-compatible modalities. The recent development of fiber-coupled femtosecond lasers will enable endoscopic multiphoton microscopy (MPM). We demonstrated two- and three-photon excited fluorescence (2PEF, 3PEF), and second- and third-harmonic generation microscopy (SHG, THG) in human ovarian and fallopian tube tissue. A study was undertaken to understand the mechanisms of contrast in these images. Six patients (normal, cystadenoma, and ovarian adenocarcinoma) provided ovarian and fallopian tube biopsies. The tissue was imaged with three-dimensional optical coherence tomography, multiphoton microscopy, and frozen for histological sectioning. Tissue sections were stained with hematoxylin and eosin, Masson's trichrome, and Sudan black. Approximately 1 μm resolution images were obtained with an excitation source at 1550 nm. 2PEF signal was absent. SHG signal was mainly from collagen. 3PEF and THG signal came from a variety of sources, including a strong signal from fatty connective tissue and red blood cells. Adenocarcinoma was characterized by loss of SHG signal, whereas cystic abnormalities showed strong SHG. There was limited overlap of two- and three- photon signals, suggesting that three-photon imaging can provide additional information for early diagnosis of ovarian cancer.
Numerical Simulation of Non-Thermal Food Preservation
NASA Astrophysics Data System (ADS)
Rauh, C.; Krauss, J.; Ertunc, Ö.; Delgado, a.
2010-09-01
Food preservation is an important process step in food technology regarding product safety and product quality. Novel preservation techniques are currently developed, that aim at improved sensory and nutritional value but comparable safety than in conventional thermal preservation techniques. These novel non-thermal food preservation techniques are based for example on high pressures up to one GPa or pulsed electric fields. in literature studies the high potential of high pressures (HP) and of pulsed electric fields (PEF) is shown due to their high retention of valuable food components as vitamins and flavour and selective inactivation of spoiling enzymes and microorganisms. for the design of preservation processes based on the non-thermal techniques it is crucial to predict the effect of high pressure and pulsed electric fields on the food components and on the spoiling enzymes and microorganisms locally and time-dependent in the treated product. Homogenous process conditions (especially of temperature fields in HP and PEF processing and of electric fields in PEF) are aimed at to avoid the need of over-processing and the connected quality loss and to minimize safety risks due to under-processing. the present contribution presents numerical simulations of thermofluiddynamical phenomena inside of high pressure autoclaves and pulsed electric field treatment chambers. in PEF processing additionally the electric fields are considered. Implementing kinetics of occurring (bio-) chemical reactions in the numerical simulations of the temperature, flow and electric fields enables the evaluation of the process homogeneity and efficiency connected to different process parameters of the preservation techniques. Suggestions to achieve safe and high quality products are concluded out of the numerical results.
Chugh, Anupam; Khanal, Dipendra; Walkling-Ribeiro, Markus; Corredig, Milena; Duizer, Lisa; Griffiths, Mansel W.
2014-01-01
Non-thermal processing methods, such as pulsed electric field (PEF) and tangential-flow microfiltration (TFMF), are emerging processing technologies that can minimize the deleterious effects of high temperature short time (HTST) pasteurization on quality attributes of skim milk. The present study investigates the impact of PEF and TFMF, alone or in combination, on color and volatile compounds in skim milk. PEF was applied at 28 or 40 kV/cm for 1122 to 2805 µs, while microfiltration (MF) was conducted using membranes with three pore sizes (lab-scale 0.65 and 1.2 µm TFMF, and pilot-scale 1.4 µm MF). HTST control treatments were applied at 75 or 95 °C for 20 and 45 s, respectively. Noticeable color changes were observed with the 0.65 µm TFMF treatment. No significant color changes were observed in PEF-treated, 1.2 µm TFMF-treated, HTST-treated, and 1.4 µm MF-treated skim milk (p ≥ 0.05) but the total color difference indicated better color retention with non-thermal preservation. The latter did not affect raw skim milk volatiles significantly after single or combined processing (p ≥ 0.05), but HTST caused considerable changes in their composition, including ketones, free fatty acids, hydrocarbons, and sulfur compounds (p < 0.05). The findings indicate that for the particular thermal and non-thermal treatments selected for this study, better retention of skim milk color and flavor components were obtained for the non-thermal treatments. PMID:28234317
The influence of medium conductivity on cells exposed to nsPEF
NASA Astrophysics Data System (ADS)
Moen, Erick K.; Ibey, Bennett L.; Roth, Caleb C.; Barnes, Ronald A.; Beier, Hope T.; Armani, Andrea M.
2017-02-01
Nanosecond pulsed electric fields (nsPEF) have proven useful for transporting cargo across cell membranes and selectively activating cellular pathways. The chemistry and biophysics governing this cellular response, however, are complex and not well understood. Recent studies have shown that the conductivity of the solution cells are exposed in could play a significant role in plasma membrane permeabilization and, thus, the overall cellular response. Unfortunately, the means of detecting this membrane perturbation has traditionally been limited to analyzing one possible consequence of the exposure - diffusion of molecules across the membrane. This method has led to contradictory results with respect to the relationship between permeabilization and conductivity. Diffusion experiments also suffer from "saturation conditions" making multi-pulse experiments difficult. As a result, this method has been identified as a key stumbling block to understanding the effects of nsPEF exposure. To overcome these limitations, we recently developed a nonlinear optical imaging technique based on second harmonic generation (SHG) that allows us to identify nanoporation in live cells during the pulse in a wide array of conditions. As a result, we are able to explore and fully test whether lower conductivity extracellular solutions could induce more efficient nanoporation. This hypothesis is based on membrane charging and the relative difference between the extracellular solution and the cytoplasm. The experiments also allow us to test the noise floor of our methodology against the effects of ion leakage. The results emphasize that the electric field, not ionic phenomenon, are the driving force behind nsPEF-induced membrane nanoporation.
Sun, Chen; Hou, Jian; Pan, Guangming; Xia, Zhizeng
2016-01-01
A successful cross-linked polymer flooding has been implemented in JD reservoir, an ordinary heavy oil reservoir with high permeability zones. For all that, there are still significant volumes of continuous oil remaining in place, which can not be easily extracted due to stronger vertical heterogeneity. Considering selective plugging feature, polymer enhanced foam (PEF) flooding was taken as following EOR technology for JD reservoir. For low cost and rich source, natural gas was used as foaming gas in our work. In the former work, the surfactant systems CEA/FSA1 was recommended as foam agent for natural gas foam flooding after series of compatibility studies. Foam performance evaluation experiments showed that foaming volume reached 110 mL, half-life time reached 40 min, and dimensionless filter coefficient reached 1.180 when CEA/FSA1 reacted with oil produced by JD reservoir. To compare the recovery efficiency by different EOR technologies, series of oil displacement experiments were carried out in a parallel core system which contained cores with relatively high and low permeability. EOR technologies concerned in our work include further cross-linked polymer (C-P) flooding, surfactant-polymer (S-P) flooding, and PEF flooding. Results showed that PEF flooding had the highest enhanced oil recovery of 19.2 % original oil in place (OOIP), followed by S-P flooding (9.6 % OOIP) and C-P flooding (6.1 % OOIP). Also, produced liquid percentage results indicated PEF flooding can efficiently promote the oil recovery in the lower permeability core by modifying the injection profile.
Walkling-Ribeiro, M; Noci, F; Cronin, D A; Lyng, J G; Morgan, D J
2009-01-01
The impact of a combined hurdle treatment of heat and pulsed electric fields (PEF) was studied on native microbiota used for the inoculation of low-fat ultra-high temperature (UHT) milk and whole raw milk. Microbiological shelf-life of the latter following hurdle treatment or thermal pasteurization was also investigated. UHT milk was preheated to 30 degrees C, 40 degrees C or 50 degrees C over a 60-s period, pulsed for 50 micros or 60 micros at a field strength of 40 kV cm(-1) or for 33 micros at 50 kV cm(-1). Heat and PEF reduced the microbial count by a maximum of 6.4 log in UHT milk (50 degrees C; 50 kV cm(-1), 33 micros) compared to 6.0 log (P > or = 0.05) obtained by thermal pasteurization (26 s, 72 degrees C). When raw milk was treated with a combination of hurdles (50 degrees C; 40 kV cm(-1), 60 micros) a 6.0 log inactivation of microbiota was achieved and microbiological milk shelf-life was extended to 21 days under refrigeration (4 degrees C) vs 14 days in thermally pasteurized milk. Native microbiota was decreased by 6.7 log following conventional pasteurization. The findings suggest that heat and PEF achieved similar inactivation of native microbiota in milk and longer stabilization of microbiological shelf-life than thermal pasteurization. A hurdle approach of heat and PEF could represent a valid milk processing alternative to conventional pasteurization. Hurdle treatment might also preserve native milk quality better due to less thermal exposure.
Conformational effect of dicyclo-hexano-18-crown-6 on isotopic fractionation of zinc: DFT approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boda, A.; Singha Deb, A. K.; Ali, Sk. M.
2014-04-24
Generalized gradient approximated BP86 density functional employing triple zeta valence plus polarization (TZVP) basis set has been used to compute the reduced partition function ratio and isotopic separation factor for zinc isotopes. The isotopic separation factor was found to be in good agreement with the experimental results. The isotopic separation factor was found to depend on the conformation of the crown ether ligand. The trans-trans conformation shows the highest fractionation compared to cis-cis conformer. The present theoretical results can thus be used to plan the isotope separation experiments.
Carr, Lynn; Bardet, Sylvia M; Arnaud-Cormos, Delia; Leveque, Philippe; O'Connor, Rodney P
2018-02-01
Cytosolic, synthetic chemical calcium indicators are typically used to visualise the rapid increase in intracellular calcium ion concentration that follows nanosecond pulsed electric field (nsPEF) application. This study looks at the application of genetically encoded calcium indicators (GECIs) to investigate the spatiotemporal nature of nsPEF-induced calcium signals using fluorescent live cell imaging. Calcium responses to 44kV/cm, 10ns pulses were observed in U87-MG cells expressing either a plasma membrane targeted GECI (GCaMP5-G), or one cytosolically expressed (GCaMP6-S), and compared to the response of cells loaded with cytosolic or plasma membrane targeted chemical calcium indicators. Application of 100 pulses, to cells containing plasma membrane targeted indicators, revealed a wave of calcium across the cell initiating at the cathode side. A similar spatial wave was not observed with cytosolic indicators with mobile calcium buffering properties. The speed of the wave was related to pulse application frequency and it was not propagated by calcium induced calcium release. Copyright © 2017 Elsevier B.V. All rights reserved.
Aguiló-Aguayo, Ingrid; Suarez, Manuel; Plaza, Lucia; Hossain, Mohammad B; Brunton, Nigel; Lyng, James G; Rai, Dilip K
2015-07-01
The effect of pulsed electric field (PEF) treatment variables (electric field strength and treatment time) on the glucosinolate content of broccoli flowers and stalks was evaluated. Samples were subjected to electric field strengths from 1 to 4 kV cm(-1) and treatment times from 50 to 1000 µs at 5 Hz. Data fitted significantly (P < 0.0014) the proposed second-order response functions. The results showed that PEF combined treatment conditions of 4 kV cm(-1) for 525 and 1000 µs were optimal to maximize glucosinolate levels in broccoli flowers (ranging from 187.1 to 212.5%) and stalks (ranging from 110.6 to 203.0%) respectively. The predicted values from the developed quadratic polynomial equation were in close agreement with the actual experimental values, with low average mean deviations (E%) ranging from 0.59 to 8.80%. The use of PEF processing at moderate conditions could be a suitable method to stimulate production of broccoli with high health-promoting glucosinolate content. © 2014 Society of Chemical Industry.
Ortiz, X; Martí, R; Montaña, M J; Gasser, M; Margarit, L; Broto, F; Díaz-Ferrero, J
2010-09-01
The analysis of persistent organic pollutants in foodstuffs has become necessary for control of their levels in products for human and animal consumption. These analytical procedures usually require a fractionation step in order to separate the different families of pollutants to avoid interferences during the instrumental determination. In this study the separation was carried out on a 2-(1-pyrenyl)ethyl silica column, where analyte fractionation was based on differences in planarity and aromaticity. The fractionation of several types of persistent organic pollutants found in fish oil samples was studied; the pollutants included polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls, polybrominated diphenyl ethers, and some organochlorine pesticides. Fractions were analyzed by high-resolution gas chromatography with electron-capture detection and high-resolution gas chromatography-high resolution mass spectroscopy. Finally, the whole method (including the purification, fractionation, and instrumental determination steps) was validated and successfully applied to the analysis of several samples of fish oil.
Yu, Kai; Gu, Cheng; Boyd, Stephen A; Liu, Cun; Sun, Cheng; Teppen, Brian J; Li, Hui
2012-08-21
Subnanoscale zerovalent iron (ZVI) synthesized using smectite clay as a template was utilized to investigate reduction of decabromodiphenyl ether (DBDE). The results revealed that DBDE was rapidly debrominated by the prepared smectite-templated ZVI with a reaction rate 10 times greater than that by conventionally prepared nanoscale ZVI. This enhanced reduction is plausibly attributed to the smaller-sized smectite-templated ZVI clusters (∼0.5 nm) vs that of the conventional nanoscale ZVI (∼40 nm). The degradation of DBDE occurred in a stepwise debromination manner. Pentabromodiphenyl ethers were the terminal products in an alkaline suspension (pH 9.6) of smectite-templated ZVI, whereas di-, tri-, and tetrabromodiphenyl ethers formed at the neutral pH. The presence of tetrahydrofuran (THF) as a cosolvent at large volume fractions (e.g., >70%) in water reduced the debromination rates due to enhanced aggregation of clay particles and/or diminished adsorption of DBDE to smectite surfaces. Modification of clay surfaces with tetramethylammonium (TMA) attenuated the colsovent effect on the aggregation of clay particles, resulting in enhanced debromination rates. Smectite clay provides an ideal template to form subnanoscale ZVI, which demonstrated superior debromination reactivity with DBDE compared with other known forms of ZVIs. The ability to modify the nature of smectite clay surface by cation exchange reaction utilizing organic cations can be harnessed to create surface properties compatible with various contaminated sites.
NASA Astrophysics Data System (ADS)
Usacheva, T. R.; Sharnin, V. A.; Chernov, I. V.; Matteoli, E.; Terekhova, I. V.; Kumeev, R. S.
2012-08-01
The influence of water-ethanol mixture composition on the complex formation between 18-crown-6 ether and L-phenylalanine was studied by titration calorimetry at Т = 298.15 K. The standard thermodynamic parameters (ΔrGо, ΔrHо, ТΔrSо) of formation of [Phe18C6] molecular complex were calculated from data obtained by means of the microcalorimetric system TAM III (TA Instruments, USA) at X(EtOH) = 0.0/0.6 mol fraction. The stability of [Phe18C6] and the mechanism of complexation in water were investigated using the 1Н and 13С NMR spectroscopy. The increase of EtOH concentration results in an increase of the complex stability and of the exothermicity of complexation.
You, Rong-Rong; Chen, Xue-Qing; He, Dan-Dan; Huang, Chang-Gao; Jin, Yang; Qian, Shi-Hui; Ju, Jian-Ming; Fan, Jun-Ting
2017-10-01
The present work is to study the chemical constituents from petroleum ether fraction of Tibetan medicine Swertia chirayita by column chromatography and recrystallization. The structures were identified by physical and chemical properties and spectral data as swerchirin (1), decussatin (2), 1,8-dihydroxy-3,5,7-trimethoxyxanthone (3), 1-hydroxy-3,5,7,8-tetramethoxyxanthone (4), bellidifolin (5), 1-hydroxy-3, 7-dimethoxyxanthone (6), methylswertianin (7), 1-hydroxy-3,5-dimethoxyxanthone (8), erythrodiol (9), oleanolic acid (10), gnetiolactone (11), scopoletin (12), sinapaldehyde (13), syringaldehyde (14), and β-sitosterol (15). Compounds 3, 4, 9, 11-14 were isolated from S. chirayita for the first time. Compounds 9 and 12 were firstly isolated from the genus Swertia. The cytotoxic activities of compounds 1, 2, 5, 7 and 8 against human pancreatic cancer cell lines SW1990 and BxPC-3,and the protective effects of these compounds against hydrogen peroxide (H2O2)-induced oxidative stress in human endothelium-derived EA.hy926 were investigated in vitro. The results showed no obvious effect at the high concentration of 50 μmol•L⁻¹. Copyright© by the Chinese Pharmaceutical Association.
Larvicidal activity against Aedes aegypti of pacharin from Bauhinia acuruana.
da Silva Góis, Roberto Wagner; de Sousa, Leôncio Mesquita; Santiago, Gilvandete Maria Pinheiro; Romero, Nirla Rodrigues; Lemos, Telma Leda Gomes; Arriaga, Angela Martha Campos; Braz-Filho, Raimundo
2013-07-01
The aim of the present study was to evaluate the activity of pacharin isolated from the ethanol extract from roots of Bauhinia acuruana on third-instar larvae of Aedes aegypti Linn. (Diptera: Culicidae). The crude ethanol extract showed larvicidal activity at the concentration of 500 μg/mL. Given this larvicidal activity, this extract was submitted to chromatographic fractionation on a silica gel column eluted with n-hexane, dichloromethane, ethyl ether, ethyl acetate, and methanol in order to isolate the active compound(s). Pacharin, obtained in pure form from fraction eluted with ethyl ether, was evaluated for their larvicidal effects against A. aegypti. In these bioassays, the larvae were exposed at concentrations of 500, 250, 100, 50, and 25 μg/mL of the crude ethanol extract or pacharin. After 24 h, the number of dead larvae was counted and the LC₅₀ values for larval mortality were calculated. Pacharin showed LC50 value of 78.9 ± 1.8 μg/mL. The structure of isolated compound was identified on the basis of their spectral data (IR, 1D- and 2D-NMR) and by comparison with literature spectral data. The results indicate pacharin as a potential natural larvicide.
Poet, Torka; Ball, Nicholas; Hays, Sean M
2016-01-01
Glycol ethers are a widely used class of solvents that may lead to both workplace and general population exposures. Biomonitoring studies are available that have quantified glycol ethers or their metabolites in blood and/or urine amongst exposed populations. These biomonitoring levels indicate exposures to the glycol ethers, but do not by themselves indicate a health hazard risk. Biomonitoring Equivalents (BEs) have been created to provide the ability to interpret human biomonitoring data in a public health risk context. The BE is defined as the concentration of a chemical or metabolite in a biological fluid (blood or urine) that is consistent with exposures at a regulatory derived safe exposure limit, such as a tolerable daily intake (TDI). In this exercise, we derived BEs for general population exposures for selected E- and P-series glycol ethers based on their respective derived no effect levels (DNELs). Selected DNELs have been derived as part of respective Registration, Evaluation, Authorisation and Regulation of Chemicals (REACh) regulation dossiers in the EU. The BEs derived here are unique in the sense that they are the first BEs derived for urinary excretion of compounds following inhalation exposures. The urinary mass excretion fractions (Fue) of the acetic acid metabolites for the E-series GEs range from approximately 0.2 to 0.7. The Fues for the excretion of the parent P-series GEs range from approximately 0.1 to 0.2, with the exception of propylene glycol methyl ether and its acetate (Fue = 0.004). Despite the narrow range of Fues, the BEs exhibit a larger range, resulting from the larger range in DNELs across GEs. The BEs derived here can be used to interpret human biomonitoring data for inhalation exposures to GEs amongst the general population. Copyright © 2015 Elsevier GmbH. All rights reserved.
Inhibition of urease by extracts derived from 15 Chinese medicinal herbs.
Shi, Da-Hua; Liu, Yu-Wei; Liu, Wei-Wei; Gu, Zhi-Feng
2011-07-01
Helicobacter pylori is a major causative factor in gastritis-like disorders, and urease plays a key role in Helicobacter pylori colonizing and persisting in the mucous layer of the human stomach. In China, a variety of Chinese medicinal herbs have been prescribed to attenuate or eradicate gastritis-like disorders. However, little is known about the urease inhibition of Chinese medicinal herbs. The present study was conducted to investigate the urease inhibition activities of the ethanol and water extracts of 15 Chinese medicinal herbs. The ethanol and water extracts derived from 15 medicinal herbs, traditionally used for the treatment of gastritis-like disorders in China, were tested for urease-inhibition activity using the phenol red method. Screened at 10 µg/mL, 14 ethanol extracts and 10 water extracts showed urease inhibition. The ethanol extracts of Magnolia officinalis Rehd. et Wils. (Magnoliaceae) and Cassia obtusifolia L. (Leguminosae) possessed inhibition rates higher than 50% with IC₅₀ values of 6.5 and 12.3 µg/mL, respectively. After fractionating successively, the petroleum ether fraction of the ethanol extracts of Magnolia officinalis showed the best activity with 90.8% urease inhibition at a concentration of 10 µg/mL. The bioautography of the petroleum ether fraction indicated the existence of the urease inhibitors in the herb. The present results indicated that some Chinese medicinal herbs might treat gastritis-like disorders via the inhibition of Helicobacter pylori urease and the further possibility for discovering useful novel urease inhibitors from the Chinese medicinal herbs.
Chatatikun, Moragot; Chiabchalard, Anchalee
2017-11-09
Ultraviolet radiation from sunlight induces overproduction of reactive oxygen species (ROS) resulting in skin photoaging and hyperpigmentation disorders. Novel whitening and anti-wrinkle compounds from natural products have recently become of increasing interest. The purpose of this study was to find products that reduce ROS in 14 Thai plant extracts. To determine total phenolic and flavonoid content, antioxidant activity, anti-tyrosinase activity and anti-collagenase activity, we compared extracts of 14 Thai plants prepared using different solvents (petroleum ether, dichloromethane and ethanol). Antioxidant activities were determined by DPPH and ABTS assays. Total phenolic content of the 14 Thai plants extracts was found at the highest levels in ethanol followed by dichloromethane and petroleum ether extracts, respectively, while flavonoid content was normally found in the dichloromethane fraction. Scavenging activity ranged from 7 to 99% scavenging as assessed by DPPH and ABTS assays. The ethanol leaf extract of Ardisia elliptica Thunb. had the highest phenolic content, antioxidant activity and collagenase inhibition, while Cassia alata (L.) Roxb. extract had the richest flavonoid content. Interestingly, three plants extracts, which were the ethanolic fractions of Annona squamosa L., Ardisia elliptica Thunb. and Senna alata (L.) Roxb., had high antioxidant content and activity, and significantly inhibited both tyrosinase and collagenase. Our finding show that the ethanol fractions of Annona squamosa L., Ardisia elliptica Thunb. and Senna alata (L.) Roxb. show promise as potential ingredients for cosmetic products such as anti-wrinkle agents and skin whitening products.
Ether- and Ester-Bound iso-Diabolic Acid and Other Lipids in Members of Acidobacteria Subdivision 4
Rijpstra, W. Irene C.; Hopmans, Ellen C.; Foesel, Bärbel U.; Wüst, Pia K.; Overmann, Jörg; Tank, Marcus; Bryant, Donald A.; Dunfield, Peter F.; Houghton, Karen; Stott, Matthew B.
2014-01-01
Recently, iso-diabolic acid (13,16-dimethyl octacosanedioic acid) has been identified as a major membrane-spanning lipid of subdivisions 1 and 3 of the Acidobacteria, a highly diverse phylum within the Bacteria. This finding pointed to the Acidobacteria as a potential source for the bacterial glycerol dialkyl glycerol tetraethers that occur ubiquitously in peat, soil, lakes, and hot springs. Here, we examined the lipid composition of seven phylogenetically divergent strains of subdivision 4 of the Acidobacteria, a bacterial group that is commonly encountered in soil. Acid hydrolysis of total cell material released iso-diabolic acid derivatives in substantial quantities (11 to 48% of all fatty acids). In contrast to subdivisions 1 and 3 of the Acidobacteria, 6 out of the 7 species of subdivision 4 (excepting “Candidatus Chloracidobacterium thermophilum”) contained iso-diabolic acid ether bound to a glycerol in larger fractional abundance than iso-diabolic acid itself. This is in agreement with the analysis of intact polar lipids (IPLs) by high-performance liquid chromatography-mass spectrometry (HPLC-MS), which showed the dominance of mixed ether-ester glycerides. iso-Diabolic acid-containing IPLs were not identified, because these IPLs are not released with a Bligh-Dyer extraction, as observed before when studying lipid compositions of subdivisions 1 and 3 of the Acidobacteria. The presence of ether bonds in the membrane lipids does not seem to be an adaptation to temperature, because the five mesophilic isolates contained a larger amount of ether lipids than the thermophile “Ca. Chloracidobacterium thermophilum.” Furthermore, experiments with Pyrinomonas methylaliphatogenes did not reveal a major influence of growth temperature over the 50 to 69°C range. PMID:24928878
Wang, Cuiping; Ma, Chuanxin; Jia, Weili; Wang, Dong; Sun, Hongwen; Xing, Baoshan
2017-12-01
In order to investigate the effects of dissolved humic acid (DHA) and tourmaline on uptake of 2, 2', 4, 4', 5, 5'- hexabrominated diphenyl ether (BDE-153) by Lactuca sativa, different fractions of DHA, including DHA 1 and DHA 4 , as well as different doses of tourmaline were introduced into BDE-153 contaminated solutions for plant growth. The levels of BDE-153 in L. sativa tissues were positively correlated with the Fe levels (R 2 = 0.9264) in seedings of the treatments with different doses of tourmaline. However, when adding DHA 1 and DHA 4 into the system, the correlation coefficients (R 2 ) decreased to 0.6976 and 0.5451 from 0.9264, respectively. In contrast with the Fe contents, the presence of DHAs didn't affect the R 2 between the levels of BDE-153 and the lipid contents in plant tissues. Our results indicated that both DHA 1 and DHA 4 could severely alter the BDE-153 uptake by L. sativa through reducing the Fe uptake instead of the lipid contents. Additionally, DHA 4 exhibited much stronger abilities to alter the BDE-153 accumulation than DHA 1 . Transmission electron microscopy (TEM) observations indicated that either DHA 1 or tourmaline or co-treatment with DHA and tourmaline had no negative impact on L. sativa at the cellular level. The present study provides important information for the impacts of different fractions of DHA extracted from soil on the BDE-153 migration in plant systems. Moreover, we elucidated the importance of the iron in tourmaline for migration of the polybrominated diphenyl ethers (PBDEs) in plant systems. Copyright © 2017 Elsevier Ltd. All rights reserved.
Li, Hongyu; Wu, Shaowei; Pan, Lu; Xu, Junhui; Shan, Jiao; Yang, Xuan; Dong, Wei; Deng, Furong; Chen, Yahong; Shima, Masayuki; Guo, Xinbiao
2018-01-01
Short-term exposure to ambient air pollution has been associated with lower pulmonary function and higher blood pressure (BP). However, controversy remains regarding the relationship between ambient multiple daily ozone (O 3 ) metrics and cardiopulmonary health outcomes, especially in the developing countries. To investigate and compare the short-term effects of various O 3 metrics on pulmonary function, fractional exhaled nitric oxide (FeNO) and BP in a panel study of COPD patients. We measured pulmonary function, FeNO and BP repeatedly in a total of 43 patients with COPD for 215 home visits. Daily hourly ambient O 3 concentrations were obtained from central-monitoring stations close to subject residences. We calculated various O 3 metrics [daily 1-h maximum (O 3 -1 h max), maximum 8-h average (O 3 -8 h max) and 24-h average (O 3 -24 h avg)] based on the hourly data. Daily indoor O 3 concentrations were estimated based on estimated indoor/outdoor O 3 ratios. Linear mixed-effects models were used to estimate associations of various O 3 metrics with cardiopulmonary function variables. An interquartile range (IQR) increase in ambient O 3 -8 h max (80.5 μg/m 3 , 5-d) was associated with a 5.9% (95%CI: -11.0%, -0.7%) reduction in forced expiratory volume in 1 s (FEV 1 ) and a 6.2% (95%CI: -10.9%, -1.5%) reduction in peak expiratory flow (PEF). However, there were no significant negative associations between ambient O 3 -1 h max, O 3 -24 h avg and FEV 1 , PEF. An IQR increase in ambient O 3 -1 h max (85.3 μg/m 3 , 6-d) was associated with a 6.7 mmHg (95%CI: 0.7, 12.7) increase in systolic BP. The estimated indoor O 3 were still significantly associated with reduction of FEV 1 and PEF. No significant associations were found between various O 3 metrics and FeNO. Our results provide clues for the adverse cardiopulmonary effects associated with various O 3 metrics in COPD patients and highlight that O 3 -8 h max was more closely associated with respiratory health variables. Copyright © 2017 Elsevier Ltd. All rights reserved.
Cleaning products and short-term respiratory effects among female cleaners with asthma.
Vizcaya, David; Mirabelli, Maria C; Gimeno, David; Antó, Josep-Maria; Delclos, George L; Rivera, Marcela; Orriols, Ramon; Arjona, Lourdes; Burgos, Felip; Zock, Jan-Paul
2015-11-01
We evaluated the short-term effects of exposure to cleaning products on lung function and respiratory symptoms among professional cleaning women. Twenty-one women with current asthma and employed as professional cleaners participated in a 15-day panel study. During 312 person-days of data collection, participants self-reported their use of cleaning products and respiratory symptoms in daily diaries and recorded their forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) three times per day using a handheld spirometer. We evaluated associations of cleaning product use with upper and lower respiratory tract symptoms using Poisson mixed regression models and with changes in FEV1 and PEF using linear mixed regression analyses. Participants reported using an average of 2.4 cleaning products per day, with exposure to at least one strong irritant (eg, ammonia, bleach, hydrochloric acid) on 56% of person-days. Among participants without atopy, lower respiratory tract symptoms were associated with the use of hydrochloric acid and detergents. Measurements of FEV1 and PEF taken in the evening were 174 mL (95% CI 34 to 314) and 37 L/min (CI 4 to 70), respectively, lower on days when three or more sprays were used. Evening and next morning FEV1 were both lower following the use of hydrochloric acid (-616 and -526 mL, respectively) and solvents (-751 and -1059 mL, respectively). Diurnal variation in FEV1 and PEF increased on days when ammonia and lime-scale removers were used. The use of specific cleaning products at work, mainly irritants and sprays, may exacerbate asthma. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Investigation of a direct effect of nanosecond pulse electric fields on mitochondria
NASA Astrophysics Data System (ADS)
Estlack, Larry E.; Roth, Caleb C.; Cerna, Cesario Z.; Wilmink, Gerald J.; Ibey, Bennett L.
2014-03-01
The unique cellular response to nanosecond pulsed electric field (nsPEF) exposure, as compared to longer pulse exposure, has been theorized to be due to permeabilization of intracellular organelles including the mitochondria. In this investigation, we utilized a high-throughput oxygen and pH sensing system (Seahorse® XF24 extracellular flux analyzer) to assess the mitochondrial activity of Jurkat and U937 cells after nsPEF. The XF Analyzer uses a transient micro-chamber of only a few μL in specialized cell culture micro-plates to enable oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) to be monitored in real-time. We found that for nsPEF exposures of 10 pulses at 10-ns pulse width and at 50 kV/cm e-field, we were able to cause an increase in OCR in both U937 and Jurkat cells. We also found that high pulse numbers (>100) caused a significant decrease in OCR. Higher amplitude 150 kV/cm exposures had no effect on U937 cells and yet they had a deleterious effect on Jurkat cells, matching previously published 24 hour survival data. These results suggest that the exposures were modulating metabolic activity in cells possibly due to direct effects on the mitochondria themselves. To validate this hypothesis, we isolated mitochondria from U937 cells and exposed them similarly and found no significant change in metabolic activity for any pulse number. In a final experiment, we removed calcium from the buffer solution that the cells were exposed in and found that no significant enhancement in metabolic activity was observed. These results suggest that direct permeabilization of the mitochondria is unlikely a primary effect of nsPEF exposure and calcium-mediated intracellular pathway activation is likely responsible for observed pulse-induced mitochondrial effects.
Vable, Anusha M; Kiang, Mathew V; Basu, Sanjay; Rudolph, Kara E; Kawachi, Ichiro; Subramanian, S V; Glymour, M Maria
2018-03-02
Military service is associated with smoking initiation, but U.S. veterans are also eligible for special social, financial, and healthcare benefits, which are associated with smoking cessation. A key public health question is how these offsetting pathways affect health disparities; we assessed the net effects of military service on later life pulmonary function among Korean War era veterans by childhood socio-economic status (cSES). Data came from U.S.-born male Korean War era veteran (service: 1950-1954) and non-veteran participants in the observational U.S. Health and Retirement Study who were alive in 2010 (average age = 78). Veterans (N = 203) and non-veterans (N = 195) were exactly matched using coarsened exact matching on birth year, race, coarsened height, birthplace, childhood health, and parental and childhood smoking. Results were evaluated by cSES (defined as maternal education <8 yr/unknown or ≥8 yr), in predicting lung function, as assessed by peak expiratory flow (PEF), measured in 2008 or 2010. While there was little overall association between veterans and PEF [β = 12.8 L/min; 95% confidence interval (CI): (-12.1, 37.7); p = 0.314; average non-veteran PEF = 379 L/min], low-cSES veterans had higher PEF than similar non-veterans [β = 81.9 L/min; 95% CI: (25.2, 138.5); p = 0.005], resulting in smaller socio-economic disparities among veterans compared to non-veterans [difference in disparities: β = -85.0 L/min; 95% CI: (-147.9, -22.2); p = 0.008]. Korean War era military service appears to disproportionately benefit low-cSES veteran lung functioning, resulting in smaller socio-economic disparities among veterans compared with non-veterans.
Rätsep, Matthew T; Hickman, Andrew F; Croy, B Anne
2016-12-01
Preeclampsia (PE) is a significant gestational disorder affecting 3-5% of all human pregnancies. In many PE pregnancies, maternal plasma is deficient in placental growth factor (PGF), a placentally-produced angiokine. Beyond immediate fetal risks associated with acute termination of the pregnancy, offspring of PE pregnancies (PE-F1) have higher long-term risks for hypertension, stroke, and cognitive impairment compared to F1s from uncomplicated pregnancies. At present, mechanisms that explain PE-F1 gains in postpartum risks are poorly understood. Our laboratory found that mice genetically-deleted for Pgf have altered fetal and adult brain vascular development. This is accompanied by sexually dimorphic alterations in anatomic structure in the adult Pgf -/- brain and impaired cognitive functions. We hypothesize that cerebrovascular and neurological aberrations occur in fetuses exposed to the progressive development of PE and that these brain changes impair cognitive functioning, enhance risk for stroke, elevate severity of stroke, and lead to worse stroke outcomes. These brain and placental outcomes may be linked to down-regulated PGF gene expression in early pre-implantation embryos, prior to gastrulation. This review explores our hypothesis that there are mechanistic links between low PGF detection in maternal plasma prodromal to PE, PE, and altered brain vascular, structural, and functional development amongst PE-F1s. We also include a summary of preliminary outcomes from a pilot study of 7-10 year old children that is the first to report magnetic resonance imaging, magnetic resonance angiography, and functional brain region assessment by eye movement control studies in PE-F1s. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tosounidis, Theodoros H; Sheikh, Hassaan Qaiser; Kanakaris, Nikolaos K; Giannoudis, Peter V
2017-06-01
To analyse the complications and outcomes (functional/radiographic) of Pelvic External Fixators applied as part of the definitive fixation in polytrauma patients. A single center retrospective chart review. A level-1 trauma center. We reviewed all the polytrauma patients (ISS>16) between 2007 and 2012 that had a PEF applied more than 30days. Complications including infection, aseptic loosening, neurological injury, loss of reduction, non-union and mal-union were recorded. Pelvic asymmetry and Deformity Index (DI) were measured at the immediate postoperative radiographs and final follow-up. The functional outcome at final follow up was estimated using a scale previously reported by Chiou et al. 59 patients with mean age of 38.4 (16 - 81) years and mean ISS score 28 (16- 66) were included. The PEFs were applied for mean duration of 56 (30-104) days. The average follow-up was 403days. 22 injuries were type B and 37 type C (AO/OTA). The most common symptomatic complications were pin site infection in 11 (18.6%) and loosening in 5 (8.5%) cases. 44 (74.5%) patients had satisfactory functional outcome. The immediate post-operative and final asymmetry and DI were compared between the two pelvic injury groups (type B and C fractures). The difference in displacement progression was more for type C injuries (p=0.034) but no correlation to the functional outcome was evident. PEF can be used as definitive alternative stabilization method in specific situations at polytrauma setting. Radiological displacement occurred in both type B and C injuries but the clinical outcome was not correlated to this displacement. Complications related to PEF do not affect the final clinical outcome. Therapeutic Level III. Copyright © 2017 Elsevier Ltd. All rights reserved.
Changes in protein expression of U937 and Jurkat cells exposed to nanosecond pulsed electric fields
NASA Astrophysics Data System (ADS)
Moen, Erick K.; Roth, Caleb C.; Cerna, Caesar; Estalck, Larry; Wilmink, Gerald; Ibey, Bennett L.
2013-02-01
Application of nanosecond pulsed electric fields (nsPEF) to various biological cell lines has been to shown to cause many diverse effects, including poration of the plasma membrane, depolarization of the mitochondrial membrane, blebbing, apoptosis, and intracellular calcium bursts. The underlying mechanism(s) responsible for these diverse responses are poorly understood. Of specific interest in this paper are the long-term effects of nsPEF on cellular processes, including the regulation of genes and production of proteins. Previous studies have reported transient activation of select signaling pathways involving mitogen-activated protein kinases (MAPKs), protein phosphorylation and downstream gene expression following nsPEF application. We hypothesize that nsPEF represents a unique stimulus that could be used to externally modulate cellular processes. To validate our hypothesis, we performed a series of cuvette-based exposures at 10 and 600ns pulse widths using a custom Blumlien line pulser system. We measured acute changes in the plasma membrane structure using flow cytometry by tracking phosphatidylserine externalization via FITC-Annexin V labeling and poration via propidium iodide uptake. We then compared these results to viability of the cells at 24 hours post exposure using MTT assay and changes in the MAPK family of proteins at 8 hours post-exposure using Luminex assay. By comparing exposures at 10 and 600ns duration, we found that most MAPK family-protein expression increased in Jurkat and U937 cell lines following exposure and compared well with drops in viability and changes in plasma membrane asymmetry. What proved interesting is that some MAPK family proteins (e.g. p53, STAT1), were expressed in one cell line, but not the other. This difference may point to an underlying mechanism for observed difference in cellular sensitivity to nsPEFinduced stresses.
Pipi, Angelo R F; Sirés, Ignasi; De Andrade, Adalgisa R; Brillas, Enric
2014-08-01
Here, solutions with 0.185mM of the herbicide diuron of pH 3.0 have been treated by electrochemical advanced oxidation processes (EAOPs) like electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF) or solar PEF (SPEF). Trials were performed in stirred tank reactors of 100mL and in a recirculation flow plant of 2.5L using a filter-press reactor with a Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H2O2 electrogeneration. Oxidant hydroxyl radicals were formed from water oxidation at the anode and/or in the bulk from Fenton's reaction between added Fe(2+) and generated H2O2. In both systems, the relative oxidation ability of the EAOPs increased in the sequence EO-H2O2
Medial orbital wall landmarks in three different North American populations.
Mehta, Milap P; Perry, Julian D
2015-04-01
We sought to measure the medial orbital wall foramina distances in two previously unstudied populations, to describe a new bony medial wall feature, and to validate the accuracy of a new coordinate measurement device within the orbit. Dried, well-preserved, complete human skulls without orbital defects were studied. Age, gender, birthplace, ethnicity, and laterality of the orbit were recorded for each skull. Supranumerary ethmoidal foramina were recorded, and the fronto-ethmoidal groove depth was measured. The distances between the anterior lacrimal crest (ALC) - anterior ethmoidal foramen (AEF), AEF - posterior ethmoidal foramen (PEF), and PEF - optic canal (OC) were measured first by surgical ruler and wire and then by the Microscribe coordinate measurement device. One hundred and forty-six orbits were studied. Fifty-seven orbits were of European or Caucasian descent, 68 orbits of African American descent, 2 orbits of West African descent, 11 orbits of Eskimo descent, and 8 orbits of unknown origin. No significant differences existed between the manual and Microscribe measurements for the ALC-AEF, AEF-PEF, and PEF-OF distances (p < 0.0001). A significant frontoethmoidal groove was observed in 27/146 (19%) orbits, in 6/57 (11%) Caucasian orbits, in 17/70 (24%) African American orbits, and in 4/11 (36%) Eskimo orbits. Supranumerary ethmoidal foramina were found in 50/146 orbits (34.2%) and in 17/27 (63%) orbits with a significant frontoethmoidal grooves. No significant differences in medial wall foramina distances exist between African American and Caucasian orbits; however, a frontoethmoidal groove occurs more commonly in African American orbits. This groove often occurs in the presence of supernumerary ethmoidal foramina. The Microscribe coordinate measurement system represents a valid tool to measure distances within the orbit.
C-phycocyanin extraction assisted by pulsed electric field from Artrosphira platensis.
Martínez, Juan Manuel; Luengo, Elisa; Saldaña, Guillermo; Álvarez, Ignacio; Raso, Javier
2017-09-01
This paper assesses the application of pulsed electric fields (PEF) to the fresh biomass of Artrhospira platensis in order to enhance the extraction of C-phycocyanin into aqueous media. Electroporation of A. platensis depended on both electric field strength and treatment duration. The minimum electric field intensity for detecting C-phycocyanin in the extraction medium was 15kV/cm after the application of a treatment time 150μs (50 pulses of 3μs). However higher electric field strength were required when shorter treatment times were applied. Response surface methodology was used in order to investigate the influence of electric field strength (15-25kV/cm), treatment time (60-150μs), and temperature of application of PEF (10-40°C) on C-phycocyanin extraction yield (PEY). The increment of the temperature PEF treatment reduced the electric field strength and the treatment time required to obtain a given PEY and, consequently decreased the total specific energy delivered by the treatment. For example, the increment of temperature from 10°C to 40°C permitted to reduce the electric field strength required to extract 100mg/g d w of C-phycocyanin from 25 to 18kV/cm, and the specific energy input from 106.7 to 67.5kJ/Kg. Results obtained in this investigation demonstrated PEF's potential for selectively extraction C-phycocyanin from fresh A. platensis biomass. The purity of the C-phycocyanin extract obtained from the electroporated cells was higher than that obtained using other techniques based on the cell complete destruction. Copyright © 2016 Elsevier Ltd. All rights reserved.
Maity, Soumya; Chatterjee, Suchandra; Variyar, Prasad Shekhar; Sharma, Arun; Adhikari, Soumyakanti; Mazumder, Santasree
2013-04-10
The antioxidant property of the 70% aqueous ethanol extract of Phyllanthus amarus roots and its ether-soluble, ethyl acetate-soluble, and aqueous fractions were investigated by various in vitro assays. The root extracts showed higher DPPH, hydroxyl, superoxide, and nitric oxide radical scavenging and reducing power activity. Among all the samples, the ethyl acetate-soluble fraction demonstrated highest radical scavenging activity and total phenolics content. Twenty-eight different phenolic compounds were identified by LCMS/MS analysis of the ethyl acetate-soluble fraction. The majority of the compounds were found to exist as their glycosides, and many of these were gallic acid derivatives. Free epicatechin and gallic acid were also identified in the ethyl acetate-soluble fraction. The present investigation suggested that P. amarus root is a potent antioxidant and can be used for the prevention of diseases related to oxidative stress.
Kristensen, Søren L; Jhund, Pardeep S; Køber, Lars; McKelvie, Robert S; Zile, Michael R; Anand, Inder S; Komajda, Michel; Cleland, John G F; Carson, Peter E; McMurray, John J V
2015-06-01
The aim of this study was to investigate N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and recent heart failure (HF) hospitalization as predictors of future events in heart failure - preserved ejection fraction (HF-PEF). Recently, doubt has been expressed about the value of a history of HF hospitalization as a predictor of adverse cardiovascular outcomes in patients with HF and HF-PEF. We estimated rates and adjusted hazard ratios (HRs) for the composite endpoint of cardiovascular death or HF hospitalization, according to history of recent HF hospitalization and baseline NT-proBNP level in the I-PRESERVE (Irbesartan in Heart Failure with Preserved systolic function) trial. Rates of composite endpoints in patients with (n = 804) and without (n = 1,963) a recent HF hospitalization were 12.78 (95% confidence interval [CI]: 11.47 to 14.24) and 4.49 (95% CI: 4.04 to 4.99) per 100 person-years, respectively (HR: 2.71; 95% CI: 2.33 to 3.16). For patients with NT-proBNP concentrations >360 pg/ml (n = 1,299), the event rate was 11.51 (95% CI: 10.54 to 12.58) compared to 3.04 (95% CI: 2.63 to 3.52) per 100 person-years in those with a lower level of NT-proBNP (n = 1468) (HR: 3.19; 95% CI: 2.68 to 3.80). In patients with no recent HF hospitalization and NT-proBNP ≤360 pg/ml (n = 1,187), the event rate was 2.43 (95% CI: 2.03 to 2.90) compared with 17.79 (95% CI: 15.77 to 20.07) per 100 person-years when both risk predictors were present (n = 523; HR: 6.18; 95% CI: 4.96 to 7.69). Recent hospitalization for HF or an elevated level of NT-proBNP identified patients at higher risk for cardiovascular events, and this risk was increased further when both factors were present. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
A DIETHER ANALOG OF PHOSPHATIDYL GLYCEROPHOSPHATE IN HALOBACTERIUM CUTIRUBRUM,
The major phosphatide in the extremely halophilic bacterium, Halobacterium cutirubrum, was isolated by a combination of solvent fractionation...precipitation through the barium salt, and final purification as the sodium salt. Analytical and degradative data showed the phosphatide to be a...phosphatidyl glycerophosphate with two long-chain ether groups instead of fatty acid ester groups. Both long-chain groups were found to be identical and were
Abraham, G; Yadav, R K; Kaushik, G K
2015-04-01
Azolla microphylla Kaulf. is an aquatic nitrogen fixing pteridophyte commonly found in aquatic habitats including paddy fields. Methanolic extract of the fronds of A. microphylla was subjected to partial purification by solvent partitioning with diethyl ether and ethyl acetate followed by hydrolysis, and further partitioning with ethyl acetate. The two fractions, thus obtained were tested for antibacterial activity. It was observed that the ethyl acetate fraction inhibited the growth of the pathogenic bacterium Xanthomonas oryzae. The GC-MS analysis of the ethyl acetate fraction showed several prominent peaks with retention time ranging from 8.83 to 45.54 min. A comparison of these peaks with the GC-MS libraries revealed that it could be eicosenes and heptadecanes with potential of antimicrobial activity.
Characterization of pigments from different high speed countercurrent chromatography wine fractions.
Salas, Erika; Dueñas, Montserrat; Schwarz, Michael; Winterhalter, Peter; Cheynier, Véronique; Fulcrand, Hélène
2005-06-01
A red wine, made from Cabernet Sauvignon (60%) and Tannat (40%) cultivars, was fractionated by high speed countercurrent chromatography (HSCCC). The biphasic solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water (2/2/1/5, acidified with 0.1% trifluoroacetic acid) was chosen for its demonstrated efficiency in separating anthocyanins. The different native and derived anthocyanins were identified on the basis of their UV-visible spectra, their elution time on reversed-phase high-performance liquid chromatography (HPLC), and their mass spectra, before and after thiolysis. The HSCCC method allowed the separation of different families of anthocyanin-derived pigments that were eluted in different fractions according to their structures. The hydrosoluble fraction was almost devoid of native anthocyanins. Further characterization (glucose quantification, UV-visible absorbance measurements) indicated that it contained flavanol and anthocyanin copolymers in which parts of the anthocyanin units were in colorless forms. Pigments in the hydrosoluble fraction showed increased resistance to sulfite bleaching and to the nucleophilic attack of water.
[Chemical Constituents of Ethyl Acetate Fraction of Suaeda glauca].
Qiu, Ping; Wang, Qi-zhi; Yin, Min; Wang, Ming; Zhao, You-yi; Shan, Yu; Feng, Xu
2015-04-01
To study the chemical constituents of Suaeda glauca. The chemical constituents were isolated and purified with several separation and purification techniques. Their structures were identified by physicochemical properties and various spectroscopic methods. Ten compounds were isolated from the ethyl acetate fraction as lignoceric acid (1), β-amyrin-n-nonyl ether(2), β-sitosterol(3), β-daucosterol(4), quercetin(5), luteolin(6), luteolin-7-O-β-D-glucoside(7), isorhamnetin(8), scopoletin (9) and stigmasterol(10). Compounds 1, 2, 6, 7, 8, 9 and 10 are isolated from Suaeda genus for the first time and compounds 3 - 5 are isolated from this plant for the first time.
Nonlinear model for offline correction of pulmonary waveform generators.
Reynolds, Jeffrey S; Stemple, Kimberly J; Petsko, Raymond A; Ebeling, Thomas R; Frazer, David G
2002-12-01
Pulmonary waveform generators consisting of motor-driven piston pumps are frequently used to test respiratory-function equipment such as spirometers and peak expiratory flow (PEF) meters. Gas compression within these generators can produce significant distortion of the output flow-time profile. A nonlinear model of the generator was developed along with a method to compensate for gas compression when testing pulmonary function equipment. The model and correction procedure were tested on an Assess Full Range PEF meter and a Micro DiaryCard PEF meter. The tests were performed using the 26 American Thoracic Society standard flow-time waveforms as the target flow profiles. Without correction, the pump loaded with the higher resistance Assess meter resulted in ten waveforms having a mean square error (MSE) higher than 0.001 L2/s2. Correction of the pump for these ten waveforms resulted in a mean decrease in MSE of 87.0%. When loaded with the Micro DiaryCard meter, the uncorrected pump outputs included six waveforms with MSE higher than 0.001 L2/s2. Pump corrections for these six waveforms resulted in a mean decrease in MSE of 58.4%.
Vidal, Jorge; Huiliñir, Cesar; Santander, Rocío; Silva-Agredo, Javier; Torres-Palma, Ricardo A; Salazar, Ricardo
2018-05-17
Ampicillin (AMP) is an antibiotic widely used in hospitals and veterinary clinics around the world for treating infections caused by bacteria. Therefore, it is common to find traces of this antibiotic in wastewater from these entities. In this work, we studied the mineralization of this antibiotic in solution as well as the elimination of its antimicrobial activity by comparing different electrochemical advanced oxidation processes (EAOPs), namely electro-oxidation with hydrogen peroxide (EO-H 2 O 2 ), electro-Fenton (EF), and photo electro-Fenton (PEF). With PEF process, a high degradation, mineralization, and complete elimination of antimicrobial activity were achieved in 120-min electrolysis with high efficiency. In the PEF process, fast mineralization rate is caused by hydroxyl radicals (·OH) that are generated in the bulk, on the anode surface, by UV radiation, and most importantly, by the direct photolysis of complexes formed between Fe 3+ and some organic intermediates. Moreover, some products and intermediates formed during the degradation of the antibiotic Ampicillin, such as inorganic ions, carboxylic acids, and aromatic compounds, were determined by photometric and chromatographic methods. An oxidation pathway is proposed for the complete conversion to CO 2 .
Effects of a specially pulsed electric field on an animal model of wound healing.
Cinar, Kenan; Comlekci, Selcuk; Senol, Nurgul
2009-09-01
The possible beneficial effects of a specially pulsed electric field (PEF) on wound healing were investigated in this study. We made a pair of triangular, full-thickness, dorsal incisions in the skin of 32 healthy male mice (one control group and three exposure groups). The treatment groups were kept between parallel plates in a partially insulated exposed environment. Group I was exposed to an electric field intensity of 10 kV/m, group II was exposed to 1.9 kV/m, and group III was exposed to 0.9 kV/m. PEFs were applied to the subjects for 20-22 h and 8 consecutive days. We determined the differences in wound recovery between the groups based on the following parameters: collagen fiber density, inflammatory infiltration density, capillary proliferation, and existence of exudates. We found that a 0.9 kV/m-1.9 kV/m chopped direct current (DC) electric field with a 30 micros repetition time favorably affected collagen synthesis and wound recovery. Despite the intensity of 0.9-1.9 kV/m, PEF accelerated healing, but 10 kV/m decelerated this recovery process.
Komtchou, Simon; Dirany, Ahmad; Drogui, Patrick; Robert, Didier; Lafrance, Pierre
2017-11-15
Atrazine (ATZ) is one of the most common pesticides detected in surface water in Quebec (Canada). The present study was mainly focused on the degradation of ATZ and its by-products using electrochemical advanced oxidation processes such as photo-electro-Fenton (PEF), electro-Fenton (EF) and anodic-oxidation with simultaneous H 2 O 2 formation (AO - H 2 O 2 ). The comparison of these processes showed that PEF process was found to be the most effective process in removing ATZ and its by-products from both synthetic solution (ATZ 0 = 100 μg L -1 ) and real agricultural surface water enriched with ATZ (ATZ 0 = 10 μg L -1 ). Different operating parameters, including wavelength of the light, pH, current density and the presence of natural organic matter (humic acids) were investigated for PEF process using boron-doped diamond (BDD) anode and graphite cathode. The current density and the wavelength of the light were the most important parameters in the ATZ degradation efficiency. The best operating conditions were recorded for the synthetic samples at a current density of 18.2 mA cm -2 , a pH of 3.0 and treatment time of 45 min. Results showed that atrazine-desethyl-desisopropyl (DEDIA) was the most important by-product recorded. More than 99% of ATZ oxidation was recorded after 15 min of treatment and all the concentrations of major by-products were less than the limit of detection after 45 min of treatment. The PEF process was also tested for real surface water contaminated by ATZ: i) with and without addition of iron; ii) without pH adjustment (pH ∼ 6.7) and with pH adjustment (pH ∼ 3.1). In spite of the presence of radical scavenger and iron complexation the PEF process was more effective to remove ATZ from real surface water when the pH value was adjusted near to 3.0. The ATZ removal was 96.0% with 0.01 mM of iron (k app = 0.13 min -1 ) and 100% with 0.1 mM of iron (k app = 0.17 min -1 ). Copyright © 2017 Elsevier Ltd. All rights reserved.
A New Approach for Identifying Patients with Undiagnosed Chronic Obstructive Pulmonary Disease
Mannino, David; Leidy, Nancy Kline; Malley, Karen G.; Bacci, Elizabeth D.; Barr, R. Graham; Bowler, Russ P.; Han, MeiLan K.; Houfek, Julia F.; Make, Barry; Meldrum, Catherine A.; Rennard, Stephen; Thomashow, Byron; Walsh, John; Yawn, Barbara P.
2017-01-01
Rationale: Chronic obstructive pulmonary disease (COPD) is often unrecognized and untreated. Objectives: To develop a method for identifying undiagnosed COPD requiring treatment with currently available therapies (FEV1 <60% predicted and/or exacerbation risk). Methods: We conducted a multisite, cross-sectional, case-control study in U.S. pulmonary and primary care clinics that recruited subjects from primary care settings. Cases were patients with COPD and at least one exacerbation in the past year or FEV1 less than 60% of predicted without exacerbation in the past year. Control subjects were persons with no COPD or with mild COPD (FEV1 ≥60% predicted, no exacerbation in the past year). In random forests analyses, we identified the smallest set of questions plus peak expiratory flow (PEF) with optimal sensitivity (SN) and specificity (SP). Measurements and Main Results: PEF and spirometry were recorded in 186 cases and 160 control subjects. The mean (SD) age of the sample population was 62.7 (10.1) years; 55% were female; 86% were white; and 16% had never smoked. The mean FEV1 percent predicted for cases was 42.5% (14.2%); for control subjects, it was 82.5% (15.7%). A five-item questionnaire, CAPTURE (COPD Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk), was used to assess exposure, breathing problems, tiring easily, and acute respiratory illnesses. CAPTURE exhibited an SN of 95.7% and an SP of 44.4% for differentiating cases from all control subjects, and an SN of 95.7% and an SP of 67.8% for differentiating cases from no-COPD control subjects. The PEF (males, <350 L/min; females, <250 L/min) SN and SP were 88.0% and 77.5%, respectively, for differentiating cases from all control subjects, and they were 88.0% and 90.8%, respectively, for distinguishing cases from no-COPD control subjects. The CAPTURE plus PEF exhibited improved SN and SP for all cases versus all control subjects (89.7% and 78.1%, respectively) and for all cases versus no-COPD control subjects (89.7% and 93.1%, respectively). Conclusions: CAPTURE with PEF can identify patients with COPD who would benefit from currently available therapy and require further diagnostic evaluation. Clinical trial registered with clinicaltrials.gov (NCT01880177). PMID:27783539
Buyse, Gunnar M; Voit, Thomas; Schara, Ulrike; Straathof, Chiara S M; D'Angelo, M Grazia; Bernert, Günther; Cuisset, Jean-Marie; Finkel, Richard S; Goemans, Nathalie; McDonald, Craig M; Rummey, Christian; Meier, Thomas
2015-05-02
Cardiorespiratory failure is the leading cause of death in Duchenne muscular dystrophy. Based on preclinical and phase 2 evidence, we assessed the efficacy and safety of idebenone in young patients with Duchenne muscular dystrophy who were not taking concomitant glucocorticoids. In a multicentre phase 3 trial in Belgium, Germany, the Netherlands, Switzerland, France, Sweden, Austria, Italy, Spain, and the USA, patients (age 10-18 years old) with Duchenne muscular dystrophy were randomly assigned in a one-to-one ratio with a central interactive web response system with a permuted block design with four patients per block to receive idebenone (300 mg three times a day) or matching placebo orally for 52 weeks. Study personnel and patients were masked to treatment assignment. The primary endpoint was change in peak expiratory flow (PEF) as percentage predicted (PEF%p) from baseline to week 52, measured with spirometry. Analysis was by intention to treat (ITT) and a modified ITT (mITT), which was prospectively defined to exclude patients with at least 20% difference in the yearly change in PEF%p, measured with hospital-based and weekly home-based spirometry. This study is registered with ClinicalTrials.gov, number NCT01027884. 31 patients in the idebenone group and 33 in the placebo group comprised the ITT population, and 30 and 27 comprised the mITT population. Idebenone significantly attenuated the fall in PEF%p from baseline to week 52 in the mITT (-3·05%p [95% CI -7·08 to 0·97], p=0·134, vs placebo -9·01%p [-13·18 to -4·84], p=0·0001; difference 5·96%p [0·16 to 11·76], p=0·044) and ITT populations (-2·57%p [-6·68 to 1·54], p=0·215, vs -8·84%p [-12·73 to -4·95], p<0·0001; difference 6·27%p [0·61 to 11·93], p=0·031). Idebenone also had a significant effect on PEF (L/min), weekly home-based PEF, FVC, and FEV1. The effect of idebenone on respiratory function outcomes was similar between patients with previous corticosteroid use and steroid-naive patients. Treatment with idebenone was safe and well tolerated with adverse event rates were similar in both groups. Nasopharyngitis and headache were the most common adverse events (idebenone, eight [25%] and six [19%] of 32 patients; placebo, nine [26%] and seven [21%] of 34 patients). Transient and mild diarrhoea was more common in the idebenone group than in the placebo group (eight [25%] vs four [12%] patients). Idebenone reduced the loss of respiratory function and represents a new treatment option for patients with Duchenne muscular dystrophy. Santhera Pharmaceuticals. Copyright © 2015 Elsevier Ltd. All rights reserved.
Seiber, J N; Glotfelty, D E; Lucas, A D; McChesney, M M; Sagebiel, J C; Wehner, T A
1990-01-01
A multiresidue analytical method is described for pesticides, transformation products, and related toxicants based upon high performance liquid chromatographic (HPLC) fractionation of extracted residue on a Partisil silica gel normal phase column followed by selective-detector gas chromatographic (GC) determination of components in each fraction. The HPLC mobile phase gradient (hexane to methyl t-butyl ether) gave good chromatographic efficiency, resolution, reproducibility and recovery for 61 test compounds, and allowed for collection in four fractions spanning polarities from low polarity organochlorine compounds (fraction 1) to polar N-methylcarbamates and organophosphorus oxons (fraction 4). The multiresidue method was developed for use with air samples collected on XAD-4 and related trapping agents, and water samples extracted with methylene chloride. Detection limits estimated from spiking experiments were generally 0.3-1 ng/m3 for high-volume air samples, and 0.01-0.1 microgram/L for one-liter water samples. Applications were made to determination of pesticides in fogwater and air samples.
van de Ven, W J; Vermorken, A J; Onnekink, C; Bloemers, H P; Bloemendal, H
1978-01-01
A preparative method for isolating pure viral envelopes from a type-C RNA tumor virus, Rauscher murine leukemia virus, is described. Fractionation of virions of Rauscher murine leukemia virus was studied after disruption of the virions with the detergents sodium dodecyl sulfate of Nonidet P-40 in combination with ether. Fractionation was performed through flotation in a discontinuous sucrose gradient and, as appeared from electron microscopic examination, a pure viral envelope fraction was obtained in this way. By use of sensitive competition radioimmunoassays or sodium dodecyl sulfate-polyacrylamide gel electrophoresis after immunoprecipitation with polyvalent and monospecific antisera directed against Rauscher murine leukemia virus proteins, the amount of the gag and env gene-encoded structural polypeptides in the virions and the isolated envelope fraction was compared. The predominant viral structural polypeptides in the purified envelope fraction were the env gene-encoded polypeptides gp70, p15(E), and p12(E), whereas, except for p15, there was only a relatively small amount of the gag gene-encoded structural polypeptides in this fraction. Images PMID:702639
Radiocarbon (14C) measurements provide an estimate of the fraction of carbon in a sample that is biogenic. In September 1997 during SCOS97 a series of 3-h canister samples of ambient air were collected at the Azusa air monitoring station during morning and afternoon periods. ...
Moshammer, Kai; Jasper, Ahren W; Popolan-Vaida, Denisia M; Wang, Zhandong; Bhavani Shankar, Vijai Shankar; Ruwe, Lena; Taatjes, Craig A; Dagaut, Philippe; Hansen, Nils
2016-10-04
This work provides new temperature-dependent mole fractions of elusive intermediates relevant to the low-temperature oxidation of dimethyl ether (DME). It extends the previous study of Moshammer et al. [ J. Phys. Chem. A 2015 , 119 , 7361 - 7374 ] in which a combination of a jet-stirred reactor and molecular beam mass spectrometry with single-photon ionization via tunable synchrotron-generated vacuum-ultraviolet radiation was used to identify (but not quantify) several highly oxygenated species. Here, temperature-dependent concentration profiles of 17 components were determined in the range of 450-1000 K and compared to up-to-date kinetic modeling results. Special emphasis is paid toward the validation and application of a theoretical method for predicting photoionization cross sections that are hard to obtain experimentally but essential to turn mass spectral data into mole fraction profiles. The presented approach enabled the quantification of the hydroperoxymethyl formate (HOOCH 2 OCH 2 O), which is a key intermediate in the low-temperature oxidation of DME. The quantification of this keto-hydroperoxide together with the temperature-dependent concentration profiles of other intermediates including H 2 O 2 , HCOOH, CH 3 OCHO, and CH 3 OOH reveals new opportunities for the development of a next-generation DME combustion chemistry mechanism.
NASA Astrophysics Data System (ADS)
Semelsberger, Troy A.; Borup, Rodney L.
Thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the combined processes of dimethyl ether (DME) partial oxidation and steam reforming were investigated as a function of oxygen-to-carbon ratio (0.00-2.80), steam-to-carbon ratio (0.00-4.00), temperature (100 °C-600 °C), pressure (1-5 atm) and product species. Thermodynamically, dimethyl ether processed with air and steam generates hydrogen-rich fuel-cell feeds; however, the hydrogen concentration is less than that for pure DME steam reforming. Results of the thermodynamic processing of dimethyl ether indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 °C, oxygen-to-carbon ratios greater than 0.00 and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure has negligible effects on the hydrogen content. Thermodynamically, dimethyl ether can produce concentrations of hydrogen and carbon monoxide of 52% and 2.2%, respectively, at a temperature of 300 °C, and oxygen-to-carbon ratio of 0.40, a pressure of 1 atm and a steam-to-carbon ratio of 1.50. The order of thermodynamically stable products (excluding H 2, CO, CO 2, DME, NH 3 and H 2O) in decreasing mole fraction is methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol and methyl-ethyl ether; trace amounts of formaldehyde, formic acid and methanol are observed. Ammonia and hydrogen cyanide are also thermodynamically favored products. Ammonia is favored at low temperatures in the range of oxygen-to-carbon ratios of 0.40-2.50 regardless of the steam-to-carbon ratio employed. The maximum ammonia content (i.e., 40%) occurs at an oxygen-to-carbon ratio of 0.40, a steam-to-carbon ratio of 1.00 and a temperature of 100 °C. Hydrogen cyanide is favored at high temperatures and low oxygen-to-carbon ratios with a maximum of 3.18% occurring at an oxygen-to-carbon ratio of 0.40 and a steam-to-carbon ratio of 0.00 in the temperature range of 400 °C-500 °C. Increasing the system pressure shifts the equilibrium toward ammonia and hydrogen cyanide.
NASA Astrophysics Data System (ADS)
Nebipasagil, Ali
Poly(arylene ether sulfone)s are high-performance engineering thermoplastics that have been investigated extensively over the past several decades due to their outstanding mechanical properties, high glass transition temperatures (Tg), solvent resistance and exceptional thermal, oxidative and hydrolytic stability. Their thermal and mechanical properties are highly suited to a variety of applications including membrane applications such as reverse osmosis, ultrafiltration, and gas separation. This dissertation covers structure-property-performance relationships of poly(arylene ether sulfone) and poly(ethylene oxide)-containing random and segmented copolymers for reverse osmosis and gas separation membranes. The second chapter of this dissertation describes synthesis of disulfonated poly(arylene ether sulfone) random copolymers with oligomeric molecular weights that contain hydrophilic and hydrophobic segments for thin film composite (TFC) reverse osmosis membranes. These copolymers were synthesized and chemically modified to obtain novel crosslinkable poly(arylene ether sulfone) oligomers with acrylamide groups on both ends. The acrylamideterminated oligomers were crosslinked with UV radiation in the presence of a multifunctional acrylate and a UV initiator. Transparent, dense films were obtained with high gel fractions. Mechanically robust TFC membranes were prepared from either aqueous or water-methanol solutions cast onto a commercial UDELRTM foam support. This was the first example that utilized a water or alcohol solvent system and UV radiation to obtain reverse osmosis TFC membranes. The membranes were characterized with regard to composition, surface properties, and water uptake. Water and salt transport properties were elucidated at the department of chemical engineering at the University of Texas at Austin. The gas separation membranes presented in chapter three were poly(arylene ether sulfone) and poly(ethylene oxide) (PEO)-containing polyurethanes. Poly(arylene ether sulfone) copolymers with controlled molecular weights were synthesized and chemically modified to obtain poly(arylene ether sulfone) polyols with aliphatic hydroxyethyl terminal functionality. The hydroxyethyl-terminated oligomers and a,u-hydroxy-terminated PEO were chain extended with a diisocyanate to obtain polyurethanes. Compositions with high poly(arylene ether sulfone) content relative to the hydrophilic PEO blocks were of interest due to their mechanical integrity. The membranes were characterized to analyze their compositions, thermal and mechanical properties, water uptake, and molecular weights. These membranes were also evaluated by collaborators at the University of Texas at Austin to explore single gas transport properties. The results showed that both polymer and transport properties closely related to PEO-content. The CO2/CH4 gas selectivity of our membranes were improved from 25 to 34 and the CO2/N2 gas selectivity nearly doubled from 25 to 46 by increasing PEO-content from 0 to 30 wt.% in polyurethanes. Chapter four also focuses on polymers for gas separation membranes. Disulfonated poly(arylene ether sulfone) and poly(ethylene oxide)-containing polyurethanes were synthesized for potential applications as gas separation membranes. Disulfonated polyols containing 20 and 40 mole percent of disulfonated repeat units with controlled molecular weights were synthesized. Poly(arylene ether sulfone) polyols and alpha,o-hydroxy-terminated poly(ethylene oxide) were subsequently chain extended with a diisocyanate to obtain polyurethanes. Thermal and mechanical characterization revealed that the polyurethanes had a phase-mixed complex morphology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singer, Brett C.; Destaillat, Hugo; Hodgson, Alfred T.
2005-08-01
Experiments were conducted to quantify emissions and concentrations of glycol ethers and terpenoids from cleaning product and air freshener use in a 50-m{sup 3} room ventilated at {approx}0.5 h{sup -1}. Five cleaning products were applied full-strength (FS); three were additionally used in dilute solution. FS application of pine-oil cleaner (POC) yielded 1-h concentrations of 10-1300 {micro}g m{sup -3} for individual terpenoids, including {alpha}-terpinene (90-120), d-limonene (1000-1100), terpinolene (900-1300), and {alpha}-terpineol (260-700). One-hour concentrations of 2-butoxyethanol and/or dlimonene were 300-6000 {micro}g m{sup -3} after FS use of other products. During FS application including rinsing with sponge and wiping with towels, fractionalmore » emissions (mass volatilized/dispensed) of 2-butoxyethanol and d-limonene were 50-100% with towels retained, {approx}25-50% when towels were removed after cleaning. Lower fractions (2-11%) resulted from dilute use. Fractional emissions of terpenes from FS use of POC were {approx}35-70% with towels retained, 20-50% with towels removed. During floor cleaning with dilute solution of POC, 7-12% of dispensed terpenes were emitted. Terpene alcohols were emitted at lower fractions: 7-30% (FS, towels retained), 2-9% (FS, towels removed), and 2-5% (dilute). During air-freshener use, d-limonene, dihydromyrcenol, linalool, linalyl acetate, and {beta}-citronellol were emitted at 35-180 mg d{sup -1} over three days while air concentrations averaged 30-160 {micro}g m{sup -3}.« less
Singer, B C; Destaillats, H; Hodgson, A T; Nazaroff, W W
2006-06-01
Experiments were conducted to quantify emissions and concentrations of glycol ethers and terpenoids from cleaning product and air freshener use in a 50-m3 room ventilated at approximately 0.5/h. Five cleaning products were applied full-strength (FS); three were additionally used in dilute solution. FS application of pine-oil cleaner (POC) yielded 1-h concentrations of 10-1300 microg/m3 for individual terpenoids, including alpha-terpinene (90-120), d-limonene (1000-1100), terpinolene (900-1300), and alpha-terpineol (260-700). One-hour concentrations of 2-butoxyethanol and/or d-limonene were 300-6000 microg/m3 after FS use of other products. During FS application including rinsing with sponge and wiping with towels, fractional emissions (mass volatilized/dispensed) of 2-butoxyethanol and d-limonene were 50-100% with towels retained, and approximately 25-50% when towels were removed after cleaning. Lower fractions (2-11%) resulted from dilute use. Fractional emissions of terpenes from FS use of POC were approximately 35-70% with towels retained, and 20-50% with towels removed. During floor cleaning with dilute solution of POC, 7-12% of dispensed terpenes were emitted. Terpene alcohols were emitted at lower fractions: 7-30% (FS, towels retained), 2-9% (FS, towels removed), and 2-5% (dilute). During air-freshener use, d-limonene, dihydromyrcenol, linalool, linalyl acetate, and beta-citronellol) were emitted at 35-180 mg/day over 3 days while air concentrations averaged 30-160 microg/m3. While effective cleaning can improve the healthfulness of indoor environments, this work shows that use of some consumer cleaning agents can yield high levels of volatile organic compounds, including glycol ethers--which are regulated toxic air contaminants--and terpenes that can react with ozone to form a variety of secondary pollutants including formaldehyde and ultrafine particles. Persons involved in cleaning, especially those who clean occupationally or often, might encounter excessive exposures to these pollutants owing to cleaning product emissions. Mitigation options include screening of product ingredients and increased ventilation during and after cleaning. Certain practices, such as the use of some products in dilute solution vs. full-strength and the prompt removal of cleaning supplies from occupied spaces, can reduce emissions and exposures to 2-butoxyethanol and other volatile constituents. Also, it may be prudent to limit use of products containing ozone-reactive constituents when indoor ozone concentrations are elevated either because of high ambient ozone levels or because of the indoor use of ozone-generating equipment.
Enhanced methane production from pig slurry with pulsed electric field pre-treatment.
Safavi, Seyedeh Masoumeh; Unnthorsson, Runar
2018-02-01
Intensive amount of manure produced in pig breeding sectors represents negative impact on the environment and requires optimal management. Anaerobic digestion as a well-known manure management process was optimized in this experimental study by pulsed electric field (PEF) pre-treatment. The effect of PEF on methane production was investigated at three different intensities (15, 30 and 50 kWh/m 3 ). The results indicate that the methane production and chemical oxygen demand (COD) removal was improved by continuous escalation of applied intensity, up to 50 kWh/m 3 . In comparison with untreated slurry, methane production and COD removal were increased up to 58% and 44%, respectively.
A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors
Sun, Qining; Khunsupat, Ratayakorn; Akato, Kokouvi; ...
2016-06-16
Lignins from various poplar genotypes were isolated by using organosolv fractionation and subjected to rheological treatment at various temperatures. Physicochemical characterization of the lignin variants shows a broad distribution of glass transition temperatures, melt viscosity, and pyrolysis char residues. Rheological treatment at 170 °C induces lignin repolymerization accompanied with an increase in condensed linkages, molecular weights, and viscosities. In contrast, rheology testing at 190 °C results in the decrease in lignin aliphatic and phenolic hydroxyl groups, β-O-aryl ether linkages, molecular weights, and viscosity values. Lignin under air cooling generates more oxygenated and condensed compounds, but lower amounts of ether linkagesmore » than lignin cooled under nitrogen. Here, lignin with a lower syringyl/guaiacyl ratio tends to form more cross-linkages along with higher viscosity values, higher molecular weight and larger amounts of condensed bonds.« less
Loconto, Paul R; Isenga, David; O'Keefe, Michael; Knottnerus, Mark
2008-01-01
Polybrominated diphenyl ethers (PBDEs) are isolated and recovered with acceptable percent recoveries from human serum via liquid-liquid extraction and column chromatographic cleanup and fractionation with quantitation using capillary gas chromatography-mass spectrometry with electron capture negative ion and selected ion monitoring. PBDEs are found in unspiked serum. An alternative sample preparation approach is developed using sheep serum that utilizes a formic acid pre-treatment followed by reversed-phase solid-phase disk extraction and normal-phase solid-phase cleanup using acidified silica gel that yields>50% recoveries. When these percent recoveries are combined with a minimized phase ratio for human serum and very low instrument detection limits, method detection limits below 500 parts-per-trillion are realized.
Cellular Lipids of a Nocardia Grown on Propane and n-Butane
Davis, J. B.
1964-01-01
Lipid fractions of propane- and n-butane-grown nocardial cells each contain a chloroform-soluble, ether-insoluble polymer not observed previously in liquid n-alkane-grown cells. The polymer in propane-grown cells is poly-β-hydroxybutyrate. The polymer in n-butane-grown cells apparently contains unsaturation in the molecule, and is identified tentatively as a co-polymer of β-hydroxybutyric and β-hydroxybutenoic (specifically 3-hydroxy 2-butenoic) acids. The other major component of the lipid fraction consists of triglycerides containing principally palmitic and stearic acids. There seems to be little qualitative distinction in the glycerides of propane- or n-butane-grown cells. Oxidative assimilation of n-butane is described. PMID:14199017
NASA Astrophysics Data System (ADS)
Poumellec, B.; Kraizman, V.; Aifa, Y.; Cortès, R.; Novakovich, A.; Vedrinskii, R.
1998-09-01
Angular dependence of the vanadium K-edge x-ray appearance near-edge structure (XANES) for the VOPO4.2H2O xerogel is thoroughly studied both experimentally and theoretically. The main attention is paid to the pre-edge fine structure (PEFS) of the spectra which was shown earlier to be a useful tool for the atomic short order investigations. Good quantitative agreement between theory and experiment obtained for both dipole and quadrupole contributions to the spectra proves validity of the calculation method developed and enables us to ascertain the nature of all the features in the PEFS's. The p-d mixture effect due to distortion of the central coordination octahedron and the quadrupole transitions are proved to be the only mechanisms responsible for the PEFS formation in the case considered. We show that in order to achieve quantitative agreement between experimental and theoretical spectra, it is necessary to include the effect of atomic vibrations, which makes the forbidden transitions to molecular orbitals of the central octahedron (MOCO's) dipole allowed, and to take into account deviation of the crystal layers from the substrate plane, which is not a single crystal but a texture.
Tobacco Use and Its Health Effects among Professional Athletes in Qatar
Chaabane, Zaina; Mahfoud, Ziyad
2016-01-01
The objective of the study was to determine the effects of tobacco use on selected markers of health and lung function in professional athletes. A total of 108 male professional athletes participated in the study from ten ball game teams in the same sport league in Qatar (age = 26.4 ± 5.1 yrs, height = 190.6 ± 11.9 cm, and weight = 91.5 ± 16.4 kg). The athletes have been playing professionally for about 6.3 years on average. In addition to demographic and tobacco use status, the following clinical variables were measured: resting blood pressure, heart rate, FVC, FEV1 sec, and PEF. The prevalence of tobacco use among the athletes was 27.7%. The FVC, FVC%, and FEV1% were significantly lower among the smokers compared to the nonsmokers (p = 0.003, 0.044, and 0.001, resp.). There were no significant differences between cigarettes smokers and nonsmokers in BP, HR, FEV1, FEV1/FVC, PEF, and PEF%. Similarly, those who smoked shisha had lower FEV1% values as compared to those who did not smoke shisha (p = 0.001). The decrease of FEV1 and FVC among smokers compared to nonsmokers is similar to what has been reported in the literature about other populations. PMID:28025593
Energy Factor Analysis for Gas Heat Pump Water Heaters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gluesenkamp, Kyle R
2016-01-01
Gas heat pump water heaters (HPWHs) can improve water heating efficiency with zero GWP and zero ODP working fluids. The energy factor (EF) of a gas HPWH is sensitive to several factors. In this work, expressions are derived for EF of gas HPWHs, as a function of heat pump cycle COP, tank heat losses, burner efficiency, electrical draw, and effectiveness of supplemental heat exchangers. The expressions are used to investigate the sensitivity of EF to each parameter. EF is evaluated on a site energy basis (as used by the US DOE for rating water heater EF), and a primary energy-basismore » energy factor (PEF) is also defined and included. Typical ranges of values for the six parameters are given. For gas HPWHs, using typical ranges for component performance, EF will be 59 80% of the heat pump cycle thermal COP (for example, a COP of 1.60 may result in an EF of 0.94 1.28). Most of the reduction in COP is due to burner efficiency and tank heat losses. Gas-fired HPWHs are theoretically be capable of an EF of up to 1.7 (PEF of 1.6); while an EF of 1.1 1.3 (PEF of 1.0 1.1) is expected from an early market entry.« less
2014-01-01
Background Spirometry is commonly accepted as the gold standard for the diagnosis of COPD, but the reality remains that quality assured spirometry is not or cannot be provided universally around the globe. Adding PEF measurement to a screening questionnaire may rule out airflow limitation compatible with COPD rationalizing spirometry testing. Methods We conducted a cross-sectional survey in a sample of individuals 40–80 yrs. old in Dubai, UAE. They were invited to answer a short socio-demographic questionnaire including a report on current, past history of smoking, and had PEF measured, then they conducted spirometry to identify airflow limitation compatible with COPD. Results Overall, 525 (91.0%) participants performed PEF and spirometry (68% male, with a mean age of 59 years, 17% UAE Nationals), 24% reported smoking of different sorts. Overall, 68 participants (12.9%, 95% C.I. 10.3% to 16.1%) had airflow limitation compatible with COPD. PEFR alone identified 141participants with airflow limitation compatible with COPD, with specificity of 80% and sensitivity of 73.5%. Conclusions PEFR could be an easy, cheap, and non-biased tool to assist with the case-finding of COPD before confirmation with spirometry. PMID:24739210
Development of a nonlinear fiber-optic spectrometer for human lung tissue exploration
Peyrot, Donald A.; Lefort, Claire; Steffenhagen, Marie; Mansuryan, Tigran; Ducourthial, Guillaume; Abi-Haidar, Darine; Sandeau, Nicolas; Vever-Bizet, Christine; Kruglik, Sergei G.; Thiberville, Luc; Louradour, Frédéric; Bourg-Heckly, Geneviève
2012-01-01
Several major lung pathologies are characterized by early modifications of the extracellular matrix (ECM) fibrillar collagen and elastin network. We report here the development of a nonlinear fiber-optic spectrometer, compatible with an endoscopic use, primarily intended for the recording of second-harmonic generation (SHG) signal of collagen and two-photon excited fluorescence (2PEF) of both collagen and elastin. Fiber dispersion is accurately compensated by the use of a specific grism-pair stretcher, allowing laser pulse temporal width around 70 fs and excitation wavelength tunability from 790 to 900 nm. This spectrometer was used to investigate the excitation wavelength dependence (from 800 to 870 nm) of SHG and 2PEF spectra originating from ex vivo human lung tissue samples. The results were compared with spectral responses of collagen gel and elastin powder reference samples and also with data obtained using standard nonlinear microspectroscopy. The excitation-wavelength-tunable nonlinear fiber-optic spectrometer presented in this study allows performing nonlinear spectroscopy of human lung tissue ECM through the elastin 2PEF and the collagen SHG signals. This work opens the way to tunable excitation nonlinear endomicroscopy based on both distal scanning of a single optical fiber and proximal scanning of a fiber-optic bundle. PMID:22567579
Aurora A kinase contributes to a pole-based error correction pathway
Ye, Anna A.; Deretic, Jovana; Hoel, Christopher M.; Hinman, Albert W.; Cimini, Daniela; Welburn, Julie P.; Maresca, Thomas J.
2015-01-01
Summary Chromosome biorientation, where sister kinetochores attach to microtubules (MTs) from opposing spindle poles, is the configuration that best ensures equal partitioning of the genome during cell division. Erroneous kinetochore-microtubule (kt-MT) attachments are commonplace but often corrected prior to anaphase [1, 2]. Error correction, thought to be mediated primarily by the centromere-enriched Aurora B kinase (ABK) [3-5], typically occurs near spindle poles [6]; albeit, the relevance of this locale is unclear. Furthermore, polar ejection forces (PEFs), highest near poles [7], can stabilize improper attachments by pushing mal-oriented chromosome arms away from spindle poles [8, 9]. Hence, a conundrum: erroneous kt-MT attachments are weakened where PEFs are most likely to strengthen them. Here, we report that Aurora A kinase (AAK) opposes the stabilizing effect of PEFs. AAK activity contributes to phosphorylation of kinetochore substrates near poles and its inhibition results in chromosome mis-alignment and an increased incidence of erroneous kt-MT attachments. Furthermore, AAK directly phosphorylates a site in the N-terminal tail of Ndc80/Hec1 that has been implicated in reducing the affinity of the Ndc80 complex for MTs when phosphorylated [10-12]. We propose that an AAK activity gradient contributes to correcting mal-oriented kt-MT attachments in the vicinity of spindle poles. PMID:26166783
Lung function impact from working in the pre-revolution Libyan quarry industry.
Draid, Marwan M; Ben-Elhaj, Khaled M; Ali, Ashraf M; Schmid, Kendra K; Gibbs, Shawn G
2015-05-07
The purpose of this study was to determine the lung impact from working within the Libyan quarry industry, and if the length of work impacted the degree of degradation. Eighty three workers from eight silica quarries in the Nafusa Mountains of Libya opted to participate. These quarries were working the upper cretaceous geological structure. Eighty-five individuals who lived in Gharyan City with no affiliation to quarry operations participated as controls. Spirometry variables evaluated were Forced Vital Capacity (FVC), Forced Expiratory Volume at 1.0 second (FEV1), FVC/FEV1 and Peak Expiratory Flow (PEF). Control and exposed groups had no differences in terms of height, weight, or smoking status (p = 0.18, 0.20, 0.98, respectively). Prior to adjustment for other variables, FVC, FEV1, and PEF are all significantly lower in the exposed group (p = 0.003, 0.009, 0.03, respectively). After adjustment for age, height, weight, and smoking status, there remain significant differences between the control and exposed groups for FVC, FEV1, and PEF. This analysis demonstrated that exposure to quarry dust has a detrimental effect on lung function, and that pre-revolution Libyan quarry workers were being exposed. This study shows that any exposure is harmful, as the reduction in lung function was not significantly associated with years of exposure.
The role of membrane dynamics in electrical and infrared neural stimulation
NASA Astrophysics Data System (ADS)
Moen, Erick K.; Beier, Hope T.; Ibey, Bennett L.; Armani, Andrea M.
2016-03-01
We recently developed a nonlinear optical imaging technique based on second harmonic generation (SHG) to identify membrane disruption events in live cells. This technique was used to detect nanoporation in the plasma membrane following nanosecond pulsed electric field (nsPEF) exposure. It has been hypothesized that similar poration events could be induced by the thermal gradients generated by infrared (IR) laser energy. Optical pulses are a highly desirable stimulus for the nervous system, as they are capable of inhibiting and producing action potentials in a highly localized but non-contact fashion. However, the underlying mechanisms involved with infrared neural stimulation (INS) are not well understood. The ability of our method to non-invasively measure membrane structure and transmembrane potential via Two Photon Fluorescence (TPF) make it uniquely suited to neurological research. In this work, we leverage our technique to understand what role membrane structure plays during INS and contrast it with nsPEF stimulation. We begin by examining the effect of IR pulses on CHO-K1 cells before progressing to primary hippocampal neurons. The use of these two cell lines allows us to directly compare poration as a result of IR pulses to nsPEF exposure in both a neuron-derived cell line, and one likely lacking native channels sensitive to thermal stimuli.
Photochemical Degradation of Composition B and Its Components
2007-09-01
recorded on the toluene (5.7 mg yield ), ether I (35 mg), and aceto- nitrile (17.8 mg) fractions. Irradiation of solution explosives in soils A...the soil was Soxhlet extracted with acetonitrile for 93 hours. The acetonitrile was removed with a rotary evaporator and the residue redissolved in...ionization to yield an anion of m/z 226. The traces show differences observed in samples with different initial preparation protocols at 15 days. Distance
8,14-Secopregnane glycosides from the aerial parts of Asclepias tuberosa.
Warashina, Tsutomu; Noro, Tadataka
2009-07-01
Twenty pregnane glycosides, tuberoside A(1)-L(5), were isolated from the diethyl ether-soluble fraction of the MeOH extract from the aerial parts of Asclepias tuberosa (Asclepiadaceae). The pregnane glycosides were composed of 8,12;8,20-diepoxy-8,14-secopregnane as aglycon, and D-cymarose, D-oleandrose, D-digitoxose and/or D-glucose as the component sugars. Their structures were established using NMR spectroscopic analysis and chemical methodologies.
Wu, Su-Hua; Li, Yi; Zhang, Yong-Quan; Li, Xiao-Kang; Yuan, Chao-Fan; Hao, Yu-Lin; Zhang, Zhi-Yong; Guo, Zheng
2013-12-01
Interbody fusion cages made of poly-ether-ether-ketone (PEEK) have been widely used in clinics for spinal disorders treatment; however, they do not integrate well with surrounding bone tissue. Ti-6Al-4V (Ti) has demonstrated greater osteoconductivity than PEEK, but the traditional Ti cage is generally limited by its much greater elastic modulus (110 GPa) than natural bone (0.05-30 GPa). In this study, we developed a porous Ti cage using electron beam melting (EBM) technique to reduce its elastic modulus and compared its spinal fusion efficacy with a PEEK cage in a preclinical sheep anterior cervical fusion model. A porous Ti cage possesses a fully interconnected porous structure (porosity: 68 ± 5.3%; pore size: 710 ± 42 μm) and a similar Young's modulus as natural bone (2.5 ± 0.2 GPa). When implanted in vivo, the porous Ti cage promoted fast bone ingrowth, achieving similar bone volume fraction at 6 months as the PEEK cage without autograft transplantation. Moreover, it promoted better osteointegration with higher degree (2-10x) of bone-material binding, demonstrated by histomorphometrical analysis, and significantly higher mechanical stability (P < 0.01), shown by biomechanical testing. The porous Ti cage fabricated by EBM could achieve fast bone ingrowth. In addition, it had better osseointegration and superior mechanical stability than the conventional PEEK cage, demonstrating great potential for clinical application. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.
Meltzer, Eli O; Pearlman, David S; Eckerwall, Gӧran; Uryniak, Tom; DePietro, Michael; Lampl, Kathy
2015-12-01
Budesonide is approved for delivery using a nebulized solution and dry-powder inhaler, but its use through a pressurized metered-dose inhaler (pMDI) in pediatric patients with asthma has not been determined. To examine the efficacy and safety of 160 μg twice daily of budesonide through a pMDI vs placebo in children 6 to younger than 12 years with asthma and a demonstrated need for inhaled corticosteroids. A 6-week, international, multicenter, double-blinded, parallel-group, phase 2 study randomized 304 pediatric patients (mean age, 9 years; 21.7% <8 years) 1:1 to 160 μg (80 μg × 2 inhalations) twice daily of budesonide through a pMDI or placebo after a 7- to 21-day run-in period. The primary efficacy end point was change from baseline in morning peak expiratory flow (PEF); safety end points included adverse events, vital signs, and discontinuations. Budesonide treatment significantly improved morning PEF vs placebo; mean treatment effect (budesonide vs placebo) was 13.6 L/min (P < .0001). Budesonide also showed significant improvements vs placebo for forced expiratory volume in 1 second, evening PEF, forced expiratory flow at 25% to 75% of pulmonary volume, reliever medication use, nighttime awakenings, awakenings with reliever use, and percentage of patients with at least 15- and at least 30-L/min increase in morning PEF from baseline. The numbers of patients experiencing adverse events and discontinuations were smaller in the budesonide than in the placebo group. No serious adverse events were reported. Budesonide at 160 μg twice daily through a pMDI was generally well tolerated and significantly improved lung function, symptoms, rescue medication use, and nighttime awakenings vs placebo in children 6 to younger than 12 years with asthma and a demonstrated need for inhaled corticosteroids. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Saouter, Erwan; Aschberger, Karin; Fantke, Peter; Hauschild, Michael Z; Bopp, Stephanie K; Kienzler, Aude; Paini, Alicia; Pant, Rana; Secchi, Michela; Sala, Serenella
2017-12-01
The scientific consensus model USEtox ® is recommended by the European Commission as the reference model to characterize life cycle chemical emissions in terms of their potential human toxicity and freshwater aquatic ecotoxicity impacts in the context of the International Reference Life Cycle Data System Handbook and the Environmental Footprint pilot phase looking at products (PEF) and organizations (OEF). Consequently, this model has been systematically used within the PEF/OEF pilot phase by 25 European Union industry sectors, which manufacture a wide variety of consumer products. This testing phase has raised some questions regarding the derivation of and the data used for the chemical-specific freshwater ecotoxicity effect factor in USEtox. For calculating the potential freshwater aquatic ecotoxicity impacts, USEtox bases the effect factor on the chronic hazard concentration (HC50) value for a chemical calculated as the arithmetic mean of all logarithmized geometric means of species-specific chronic median lethal (or effect) concentrations (L[E]C50). We investigated the dependency of the USEtox effect factor on the selection of ecotoxicological data source and toxicological endpoints, and we found that both influence the ecotoxicity ranking of chemicals and may hence influence the conclusions of a PEF/OEF study. We furthermore compared the average measure (HC50) with other types of ecotoxicity effect indicators, such as the lowest species EC50 or no-observable-effect concentration, frequently used in regulatory risk assessment, and demonstrated how they may also influence the ecotoxicity ranking of chemicals. We acknowledge that these indicators represent different aspects of a chemical's ecotoxicity potential and discuss their pros and cons for a comparative chemical assessment as performed in life cycle assessment and in particular within the PEF/OEF context. Environ Toxicol Chem 2017;36:3450-3462. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Kato, Kazuhiro; Sano, Hiroyuki; Tatsukawa, Toshiyuki; Nakazaki, Hirofumi; Yamasaki, Akira; Shimizu, Eiji
2016-01-01
An important aspect of sand dust emissions in association with respiratory disorders is the quantity of particulate matter. This is usually expressed as particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, the composition of PM10 and PM2.5 varies. Light detection and ranging is used to monitor sand dust particles originating in East Asian deserts and distinguish them from air pollution aerosols. The objective of this study was to investigate the association between the daily levels of sand dust particles and pulmonary function in schoolchildren in western Japan. In this panel study, the peak expiratory flow (PEF) of 399 schoolchildren was measured daily from April to May 2012. A linear mixed model was used to estimate the association of PEF with the daily levels of sand dust particles, suspended particulate matter (SPM), and PM2.5. There was no association between the daily level of sand dust particles and air pollution aerosols, while both sand dust particles and air pollution aerosols had a significant association with SPM and PM2.5. An increment of 0.018 km(-1) in sand dust particles was significantly associated with a decrease in PEF (-3.62 L/min; 95% confidence interval, -4.66 to -2.59). An increase of 14.0 μg/m(3) in SPM and 10.7 μg/m(3) in PM2.5 led to a significant decrease of -2.16 L/min (-2.88 to -1.43) and -2.58 L/min (-3.59 to -1.57), respectively, in PEF. These results suggest that exposure to sand dust emission may relate to pulmonary dysfunction in children in East Asia. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
Effect of Asian dust on pulmonary function in adult asthma patients in western Japan: A panel study.
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Mikami, Masaaki; Yamamoto, Hiroyuki; Ueda, Yasuto; Touge, Hirokazu; Fujii, Yoshihiro; Ikeda, Toshikazu; Tokuyasu, Hirokazu; Konishi, Tatsuya; Yamasaki, Akira; Igishi, Tadashi; Shimizu, Eiji
2016-04-01
Asian dust (AD) has become a major health concern. The concentration of AD is typically expressed in particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, PM10 and PM2.5 consist of various substances besides AD. Light detection and ranging (LIDAR) systems can selectively measure the quantity of AD particles to distinguish non-spherical airborne particles from spherical airborne particles. The objective of this study was to investigate the relationship between pulmonary function in adult asthma patients and AD using LIDAR data. Subjects were 231 adult asthma patients who had their morning peak expiratory flow (PEF) measured from March to May 2012. A linear mixed model was used to estimate the association of PEF with sand dust particles detected by LIDAR. Increases in the interquartile range of AD particles (0.018 km(-1)) led to changes in PEF of -0.42 L/min (95% confidence interval [CI], -0.85 to 0.01). An increase of 11.8 μg/m(3) in suspended particulate matter and 6.9 μg/m(3) in PM2.5 led to decreases of -0.17 L/min (-0.53 to 0.21) and 0.03 L/min (-0.35 to 0.42), respectively. A heavy AD day was defined as a day with a level of AD particles >0.032 km(-1), which was the average plus one standard deviation during the study period, and six heavy AD days were identified. Change in PEF after a heavy AD day was -0.97 L/min (-1.90 to -0.04). Heavy exposure to AD particles was significantly associated with decreased pulmonary function in adult asthma patients. Copyright © 2015 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.
Basri, Aida Maryam; Taha, Hussein; Ahmad, Norhayati
2017-01-01
The rhizomes of Alpinia officinarum Hance have been used conventionally for the treatment of various ailments, triggering a wide interest from the scientific research community on this ethnomedicinal plant. This review summarizes the phytochemical and pharmacological properties of the extracts and fractions from A. officinarum, a plant species of the Zingiberaceae family. Different parts of the plant – leaves, roots, rhizomes, and aerial parts – have been extracted in various solvents – methanol, ethanol, ethyl acetate, hexane, dichloromethane, aqueous, chloroform, and petroleum ether, using various techniques – Soxhlet extraction, maceration, ultrasonication, and soaking, whereas fractionation of the plant extracts involves the solvent–solvent partition method. The extracts, fractions, and isolated compounds have been studied for their biological activities – antioxidant, antibacterial, anti-inflammatory, anticancer, antiproliferative, inhibition of enzymes, as well as the inhibition of nitric oxide production. More findings on A. officinarum are certainly important to further develop potential bioactive drug compounds. PMID:28503054
Lv, Jitao; Zhang, Shuzhen; Wang, Songshan; Luo, Lei; Cao, Dong; Christie, Peter
2016-03-01
Adsorption by minerals is a common geochemical process of dissolved organic matter (DOM) which may induce fractionation of DOM at the mineral-water interface. Here, we examine the molecular fractionation of DOM induced by adsorption onto three common iron oxyhydroxides using electrospray ionization coupled with Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS). Ferrihydrite exhibited higher affinity to DOM and induced more pronounced molecular fractionation of DOM than did goethite or lepidocrocite. High molecular weight (>500 Da) compounds and compounds high in unsaturation or rich in oxygen including polycyclic aromatics, polyphenols and carboxylic compounds had higher affinity to iron oxyhydroxides and especially to ferrihydrite. Low molecular weight compounds and compounds low in unsaturation or containing few oxygenated groups (mainly alcohols and ethers) were preferentially maintained in solution. This study confirms that the double bond equivalence and the number of oxygen atoms are valuable parameters indicating the selective fractionation of DOM at mineral and water interfaces. The results of this study provide important information for further understanding the behavior of DOM in the natural environment.
Ganesan, P; Kumar, Chandini S; Bhaskar, N
2008-05-01
In vitro antioxidant activities of three selected Indian red seaweeds - viz., Euchema kappaphycus, Gracilaria edulis and Acanthophora spicifera were evaluated. Total phenolic content and reducing power of crude methanol extract were determined. The antioxidant activities of total methanol extract and five different solvent fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane (DCM), butanol (BuOH) and aqueous) were also evaluated. EA fraction of A. spicifera exhibited higher total antioxidant activity (32.01 mg ascorbic acid equivalent/g extract) among all the fractions. Higher phenolic content (16.26 mg gallic acid equivalent/g extract) was noticed in PE fraction of G. edulis. Reducing power of crude methanol extract increased with increasing concentration of the extract. Reducing power and hydroxyl radical scavenging activity of E. kappaphycus were higher compared to standard antioxidant (alpha-tocopherol). The total phenol content of all the seaweeds was significantly different (P<0.05). In vitro antioxidant activities of methanol extracts of all the three seaweeds exhibited dose dependency; and increased with increasing concentration of the extract.
Kukafka, D S; Lang, D M; Porter, S; Rogers, J; Ciccolella, D; Polansky, M; D'Alonzo, G E
1998-12-01
Exercise-induced bronchospasm (EIB) affects up to 35% of athletes and up to 90% of asthmatics. Asthma morbidity and mortality have increased over the past several decades among residents of Philadelphia, PA. It is possible that a simple free running test for EIB may serve as a tool to study the factors contributing to recent trends in asthma, and to screen for asthma in athletes in the urban setting. The purposes of this study were to (1) assess a free running test to screen for EIB, and (2) examine prevalence of and epidemiologic factors associated with EIB in high school athletes. Cross-sectional observational study on the incidence and risk factors for EIB. To validate our method and criteria for the diagnosis of EIB, a repeat test was performed on a portion of the athletes. In a randomized single-blinded fashion, 15 athletes who had demonstrated EIB initially received albuterol or placebo prior to a repeat exercise test. Community high school athletic facilities. We studied 238 male high school varsity football players. All athletes underwent an acquaintance session with a questionnaire, followed by a 1-mile outdoor run (6 to 8 mins). Peak expiratory flow (PEF) measurements were determined prior to and 5, 15, and 30 min after exercise. Heart rates (HRs) and dyspnea scores were measured. EIB was defined as a decrease of 15% in PEF at any time point after exercise. Associations of EIB with demographic factors were assessed by univariate and multivariate analyses. Two hundred thirty-eight athletes participated: 92 European-Americans (EA), 140 African-Americans (AA), 5 Hispanics, and 1 Native American. Mean age was 16+/-1 years. Average HR postexercise was 156+/-24 beats/min. Twenty-four (10%) reported a history of treated asthma. The prevalence of EIB among the remaining 214 athletes was 19 of 214 (9%). The rate of EIB among AA athletes was higher than among EA athletes: (17/126 [13%] AA vs 2/82 [2%] EA, p = 0.01). During the validation portion of the study, the placebo-treated group (n = 7) demonstrated a consistent drop in PEF after exercise on repeat testing, with a 16+/-5% fall in PEF on initial testing and a 14+/-13 drop with placebo. In contrast, the fall in airflow in the albuterol-treated athletes (n = 8) following exercise reversed with albuterol treatment, from a 15+/-6% fall in PEF at initial testing to an increase in PEF of 6+/-9% from baseline following albuterol administration. A history of wheezing (p < 0.001), residence in a poverty area (p < 0.0001), race (p = 0.01), remote history of asthma (p < 0.001), and absolute water content of the air on the day tested (p = 0.04) were significantly associated with EIB. By stepwise regression, EIB was most closely associated with a history of wheezing (p = 0.001) and poverty area residence (p = 0.003). Our findings indicate a substantial rate of unrecognized EIB exists among urban varsity athletes, and suggest that active screening for EIB, especially for students residing in poverty areas, may be indicated to identify individuals at risk for EIB and asthma.
Weekly Personal Ozone Exposure and Respiratory Health in a Panel of Greek Schoolchildren.
Karakatsani, Anna; Samoli, Evangelia; Rodopoulou, Sophia; Dimakopoulou, Konstantina; Papakosta, Despina; Spyratos, Dionisios; Grivas, Georgios; Tasi, Sofia; Angelis, Nikolaos; Thirios, Athanasios; Tsiotsios, Anastasios; Katsouyanni, Klea
2017-07-21
The association of ozone exposure with respiratory outcomes has been investigated in epidemiologic studies mainly including asthmatic children. The findings reported had methodological gaps and inconsistencies. We aimed to investigate effects of personal ozone exposure on various respiratory outcomes in school-age children generally representative of the population during their normal activities. We conducted a panel study in a representative sample of school-age children in the two major cities of Greece, Athens and Thessaloniki. We followed 188, 10- to 11-y-old, elementary school students for 5 wk spread throughout the 2013–2014 academic year, during which ozone was measured using personal samplers. At the end of each study week, spirometry was performed by trained physicians, and the fractional concentration of nitric oxide in exhaled air ( F eNO ) was measured. Students kept a daily time–activity–symptom diary and measured PEF (peak expiratory flow) using peak flow meters. Mixed models accounting for repeated measurements were applied. An increase of 10 μg/m 3 in weekly ozone concentration was associated with a decrease in FVC (forced vital capacity) and FEV 1 (forced expiratory volume in 1 s) of 0.03 L [95% confidence interval (CI): −0.05, −0.01] and 0.01 L (95% CI: −0.03, 0.003) respectively. The same increase in exposure was associated with a 11.10% (95% CI: 4.23, 18.43) increase in F eNO and 19% (95% CI: −0.53, 42.75) increase in days with any symptom. The effect estimates were robust to PM 10 adjustment. No inverse association was found between ozone exposure and PEF. The study provides evidence that airway inflammation and the frequency of respiratory symptoms increase, whereas lung function decreases with increased ozone exposure in schoolchildren. https://doi.org/10.1289/EHP635.
Patel, Amit R.; Fatemi, Omid; Norton, Patrick T.; West, J. Jason; Helms, Adam S.; Kramer, Christopher M.; Ferguson, John D.
2008-01-01
Background Left atrial volume (LAV) determines prognosis and response to therapy in atrial fibrillation. Integration of electro-anatomical maps with 3D-images rendered from CT and MRI is used to facilitate atrial fibrillation ablation. Objectives We measured LAV changes and regional motion during the cardiac cycle that might affect the accuracy of image integration and determined their relationship to standard LAV measurements. Methods MRI was performed in thirty patients with paroxysmal atrial fibrillation. Left atrial time-volume curves were generated and used to divide the left atrial function (LAEF) into pumping (PEF) and conduit (CEF) fractions and to determine the maximum LAV (LAMAX) and the pre-atrial contraction volume (PACV). LAV was measured using an MRI angiogram and traditional geometric models from echocardiography (area-length and ellipsoid). The in-plane displacement of the pulmonary veins, anterior left atrium, mitral annulus, and left atrial appendage was measured. Results LAMAX was 107±36ml and occurred at 42±5% of the RR interval. PACV was 86 ±34ml and occurred at 81±4% of the RR interval. LAEF was 45±10% and PEF was 31±10%. LAV measurements made from the MRI angiogram, area-length and ellipsoid models underestimated LAMAX by 21±25ml, 16±26ml, and 35±22ml, respectively. The anterior LA, mitral annulus, and left atrial appendage were significantly displaced during the cardiac cycle (8.8±2.0mm, 13.2±3.8mm, and 10.2±3.4mm, respectively); the pulmonary veins were not. Conclusions LAV changes significantly during the cardiac cycle and substantial regional variation in left atrial motion exists. Standard measurements of left atrial volume significantly underestimate LAMAX when compared to the gold standard measure of 3D-volumetrics. PMID:18486563
Reporter gene assay for fish-killing activity produced by Pfiesteria piscicida.
Fairey, E R; Edmunds, J S; Deamer-Melia, N J; Glasgow, H; Johnson, F M; Moeller, P R; Burkholder, J M; Ramsdell, J S
1999-01-01
Collaborative studies were performed to develop a functional assay for fish-killing activity produced by Pfiesteria piscicida. Eight cell lines were used to screen organic fractions and residual water fraction by using a 3-[4, 5-dimethylthiazol-(2-4)]-diphenyltetrazolium bromide cytotoxicity assay. Diethyl ether and a residual water fraction were cytotoxic to several cell lines including rat pituitary (GH(4)C(1)) cells. Residual water as well as preextracted culture water containing P. piscicida cells induced c-fos-luciferase expressed in GH(4)C(1) cells with a rapid time course of induction and sensitive detection. The reporter gene assay detected activity in toxic isolates of P. piscicida from several North Carolina estuaries in 1997 and 1998 and may also be suitable for detecting toxic activity in human and animal serum. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:10464070
Bioactive phenolic derivatives from Acaena splendens methanol extract.
Backhouse, N; Delporte, C; Negrete, R; Feliciano, S A San; López-Pérez, J L
2002-09-01
Acaena splendens H. et A. has been used in Chilean folk medicine for the treatment of fever and inflammation. A description of the in vivo reduction of bacterial pyrogen-induced fever in rabbits and carrageenan-induced paw oedema in guinea pigs is presented. The methanol extract named ME-1, obtained after succesive extractions with petroleum ether and dichloromethane, showed a strong antipyretic action (45.7% of effect), though the antiinflammatory activity was only observed after submitting this extract to column fractionation, giving a crude mixture of flavonoids named C4 with both activities (55.7% and 98.9% of antiinflammatory and antipyretic effect respectively at a dose of 600 mg/kg). The bioassay-guided fractionation by column chromatography afforded the active fraction, which contained (-,-)-epicatechin, tiliroside, 7-O-acetyl-3-O-beta-D-glucosyl-kaempferol and 7-beta-D-glucosyloxy-5-hydroxy-chromone. Copyright 2002 John Wiley & Sons, Ltd.
Human cytochrome P450 isozymes in metabolism and health effects of gasoline ethers.
Hong, J Y; Wang, Y Y; Mohr, S N; Bondoc, F Y; Deng, C
2001-05-01
To reduce the production of carbon monoxide and other pollutants in motor vehicle exhaust, methyl tert-butyl ether (MTBE*), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME) are added to gasoline as oxygenates for more complete combustion. Among them, MTBE is the most widely used. The possible adverse effect of MTBE in humans is a public concern, but the human enzymes responsible for metabolism of these gasoline ethers and the causes or factors for increased sensitivity to MTBE in certain individuals are totally unknown. This information is important to understanding the health effects of MTBE in humans and to assessing the human relevance of pharmacokinetics and toxicity data obtained from animals. In the present study, we demonstrated that human liver is active in metabolizing MTBE to tert-butyl alcohol (TBA), a major circulating metabolite and an exposure marker of MTBE. The activity is localized in the microsomal fraction but not in the cytosol. Formation of TBA in human liver microsomes is NADPH-dependent and is significantly inhibited by carbon monoxide, which inhibits cytochrome P450 (CYP) enzymes. These results provide strong evidence that CYP enzymes play a critical role in the metabolism of MTBE in human livers. Human liver is also active in the oxidative metabolism of 2 other gasoline ethers, ETBE and TAME. We observed a large interindividual variation in metabolizing these gasoline ethers in 15 microsomal samples prepared from normal human livers. The activity level (pmol metabolite/min/mg) ranged from 204 to 2,890 for MTBE; 179 to 3,134 for ETBE; and 271 to 8,532 for TAME. The microsomal activities in metabolizing MTBE, ETBE, and TAME correlated highly with each other (r = 0.91 to 0.96), suggesting that these ethers are metabolized by the same enzyme(s). Correlation analysis of the ether-metabolizing activities with individual CYP enzyme activities in the human liver microsomes showed that the highest degree of correlation was with CYP isoform 2A6 (CYP2A6)+ (r = 0.94 for MTBE, 0.95 for ETBE, and 0.90 for TAME), which is constitutively expressed in human livers and known to be polymorphic. CYP2A6 displayed the highest turnover number in metabolizing gasoline ethers among a battery of human CYP enzymes expressed in human B-lymphoblastoid cells. CYP2A6 coexpressed with human CYP reductase by a baculovirus expression system was also more active than CYP isoform 2E1 (CYP2E1) in the metabolism of MTBE, ETBE, and TAME. Kinetic studies on MTBE metabolism with human liver microsomes (n = 3) exhibited an apparent Michaelis constant (Km) of 28 to 89 microM and a maximum rate of metabolism (Vmax) of 215 to 783 pmol/min/mg. Metabolism of MTBE, ETBE, and TAME by human liver microsomes was inhibited by coumarin, a known substrate of human CYP2A6, in a concentration-dependent manner. Monoclonal antibody against human CYP2A6 caused a significant inhibition (75% to 95%) of the metabolism of MTBE, ETBE, and TAME in human liver microsomes. Taken together, these results clearly indicate that, in human liver, CYP2A6 is a major enzyme responsible for metabolism of MTBE, ETBE, and TAME. Although CYP2E1 metabolizes diethyl ether and was previously suggested to be involved
Metabolic inactivation of five glycidyl ethers in lung and liver of humans, rats and mice in vitro.
Boogaard, P J; de Kloe, K P; Bierau, J; Kuiken, G; Borkulo, P E; Watson, W P; van Sittert, N J
2000-05-01
1. Some glycidyl ethers (GE) have been shown to be direct mutagens in short-term in vitro tests and consequently GE are considered to be potentially mutagenic in vivo. However, GE may be metabolically inactivated in the body by two different enzymatic routes: conjugation of the epoxide moiety with the endogenous tripeptide glutathione (GSH) catalysed by glutathione S-transferase (GST) or hydrolysis of the epoxide moiety catalysed by epoxide hydrolase (EH). 2. The metabolic inactivation of five different GE, the diglycidyl ethers of bisphenol A (BADGE), 4,4'-dihydroxy-3,3',5,5'-tetramethylbiphenyl (Epikote YX4000) and 1,6-hexanediol (HDDGE) and the GE of 1-dodecanol (C12GE) and o-cresol (o-CGE), has been studied in subcellular fractions of human, C3H mouse and F344 rat liver and lung. 3. All GE were chemically very stable and resistant to aqueous hydrolysis, but were rapidly hydrolysed by EH in cytosolic and microsomal fractions of liver and lung. The aromatic GE were very good substrates for EH. In general, microsomal EH is more efficient than cytosolic EH in hydrolysis of GE, and human microsomes are more efficient than rodent microsomes. 4. The more water-soluble GE, o-CGE and HDDGE, were good substrates for GST whereas the more lipophilic GE, YX4000 and C12GE, were poor substrates for GST. In general, rodents are more efficient in GSH conjugation of GE than humans. 5. In general, the epoxide groups of YX4000 are the most and those of HDDGE the least efficiently inactivated of the five GE under study. For the other three GE no general trend was observed: the relative efficiency of inactivation varied with organ and species. 6. The large variation in metabolism observed with five representative GE indicate that GE have variable individual properties and should not be considered as a single, homogenous class of compounds.
/sup 45/Ca distribution and transport in saponin skinned vascular smooth muscle
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stout, M.A.; Diecke, F.P.
1983-04-01
/sup 45/Ca distribution and transport were studied in chemically skinned strips of caudal artery from Kyoto Wistar rats. Sarcolemmal membranes were made hyperpermeable by exposure for 60 min to solutions containing 0.1 mg/ml of saponin. Skinned helical strips responded with graded contractions to changes in ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid buffered free Ca solutions (10(-7) to 10(-5) M) and were sensitive to the Mg-ATP concentration. Tissues loaded in the presence of 10(-7) M Ca contracted in response to 10 mM caffeine. These experiments indicate the strips are skinned and possess a functional regulatory and contractile system and an intact Camore » sequestering system. /sup 45/Ca distributes in three compartments in skinned caudal artery strips. The Ca contents of two components are linear functions of the Ca-ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid concentration and desaturate at rapid rates. They correspond to the extracellular and cytoplasmic spaces. A significantly smaller component releases Ca at comparatively slower rates. /sup 45/Ca uptake by the slow component consists of an ATP-dependent and an ATP-independent fraction. The /sup 45/Ca content of the ATP-dependent fraction is a function of the free Ca concentration and is independent of the Ca-ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid concentration. Its content was enhanced by oxalate and was abolished by Triton X-100 skinning solutions. The ATP-independent component was not affected by Triton X-100 skinning and may represent Ca binding to cytoplasmic molecules and structures. The sequestered Ca was released with caffeine or Ca but not by epinephrine. The observations indicate that the sarcoplasmic reticulum and mitochondria of vascular smooth muscle strips skinned with saponin retain their functional integrity after saponin skinning.« less
In vitro antioxidant and cytotoxic properties of ethanol extract of Alpinia oxyphylla fruits.
Wang, Cheng-zhong; Yuan, Hui-hui; Bao, Xiao-li; Lan, Min-bo
2013-11-01
Alpinia oxyphylla Miquel (Zingiberaceae) is a traditional Chinese herbal medicine widely used for the treatment of intestinal disorders, urosis and diuresis. However, information about antioxidant and cytotoxic properties of its fruits remains to be elucidated. The ethanol crude extract (CE) and its fractions [petroleum ether fraction (PF), ethyl acetate fraction (EF), n-butanol fraction (BF) and water fraction (WF) extracted by petroleum ether, ethyl acetate, n-butanol and water, respectively] of A. oxyphylla fruits were investigated for their antioxidant activity and cytotoxicity. The total phenolic content (TPC) and antioxidant activity of the extracts were determined by Folin-Ciocalteu reagent, 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)), Trolox equivalent antioxidant capacity and reducing power assay. Cytotoxicity of the extracts (0-200 μg/mL) was tested on six human cancer cell lines (breast cancer cell line, cervix carcinoma cell line, lung adenocarcinoma cell line, liver carcinoma cell line, gastric cancer cell line and colon cancer cell line) using the sulforhodamine B assay. The TPC of extracts varied from 8.2 to 20.3 mg gallic acid equivalents/g dry weight. DPPH radical scavenging effect of extracts decreased in the order of EF > BF > CE > PF > WF, with IC50 values ranging from 74.7 to 680.8 μg/mL. 2,2-azo-bis(3-Ethylbenzothiazoline-6-sulfoic acid) diammonium salt scavenging activity ranged from 0.118 to 0.236 mmol Trolox equivalence/mg extract. The extracts exhibited concentration-dependent reducing power, and EF showed the highest reducing ability. A satisfactory correlation (R(2) > 0.826) between TPC and antioxidant activity was observed. In addition, EF, PF and CE exhibited potent anticancer effects on six cancer cell lines with IC50 values ranging from 40.1 to 166.3 μg/mL. The ethanol extract of A. oxyphylla fruit, especially the EF, was found to possess potent antioxidant and anticancer activities, and thus a great potential for the application in food and drug products.
Zhu, Jingbo; Liu, Baoyue; Shan, Shibo; Ding, Yanl; Kou, Zinong; Xiao, Wei
2015-08-01
In order to meet the needs of efficient purification of products from natural resources, this paper developed an automatic vacuum liquid chromatographic device (AUTO-VLC) and applied it to the component separation of petroleum ether extracts of Schisandra chinensis (Turcz) Baill. The device was comprised of a solvent system, a 10-position distribution valve, a 3-position changes valve, dynamic axis compress chromatographic columns with three diameters, and a 10-position fraction valve. The programmable logic controller (PLC) S7- 200 was adopted to realize the automatic control and monitoring of the mobile phase changing, column selection, separation time setting and fraction collection. The separation results showed that six fractions (S1-S6) of different chemical components from 100 g Schisandra chinensis (Turcz) Baill. petroleum ether phase were obtained by the AUTO-VLC with 150 mm diameter dynamic axis compress chromatographic column. A new method used for the VLC separation parameters screened by using multiple development TLC was developed and confirmed. The initial mobile phase of AUTO-VLC was selected by taking Rf of all the target compounds ranging from 0 to 0.45 for fist development on the TLC; gradient elution ratio was selected according to k value (the slope of the linear function of Rf value and development times on the TLC) and the resolution of target compounds; elution times (n) were calculated by the formula n ≈ ΔRf/k. A total of four compounds with the purity more than 85% and 13 other components were separated from S5 under the selected conditions for only 17 h. Therefore, the development of the automatic VLC and its method are significant to the automatic and systematic separation of traditional Chinese medicines.
Brine shrimp lethality assay of Bacopa monnieri.
D'Souza, Prashanth; Deepak, Mundkinajeddu; Rani, Padmaja; Kadamboor, Sandhya; Mathew, Anjana; Chandrashekar, Arun P; Agarwal, Amit
2002-03-01
Successive petroleum ether, chloroform, ethanol and water extracts, a saponin rich fraction (SRF) and bacoside A isolated from Bacopa monnieri were tested for brine shrimp lethality. Successive ethanol extracts and SRF showed potent activity. Bacoside A showed the maximum activity with a LC(50) of 38.3 microg/mL. The results confirmed the previous reports of an anticancer effect of Bacopa monnieri and suggest bacoside A as the active constituent. Copyright 2002 John Wiley & Sons, Ltd.
Nandy, Debdurlav; Mitra, Rajib K; Paul, Bidyut K
2007-06-01
The phase diagrams of the pseudo-quaternary systems poly(oxyethylene) (10) stearyl ether (Brij-76)/1-butanol/isooctane/water (with equal amounts of oil and water in the presence of two nonaqueous polar solvents (NPS), ethylene glycol (EG), and tetraethylene glycol (TEG)), have been constructed at 30 degrees C. Regular fish-tail diagrams were obtained up to psi (weight fraction of EG or TEG in the mixture of polar solvents) equal to 0.5, confirming the establishment of hydrophile-lipophile balance (HLB) of the systems. The maximum solubilization capacity passed through a minimum at psi=0.2. No HLB was obtained at higher psi. The usual fish-tail diagrams were also obtained in temperature-induced phase mapping at fixed W(1) (weight fraction of 1-butanol in total amphiphile). Solubilization capacity and HLB temperature (T(HLB)) decreased with increasing psi at a fixed W(1), the effect being more pronounced for TEG than EG. A correlation between HLB temperature (T(HLB)) and HLB number (N(HLB)) of mixed amphiphiles (Brij-76+Bu) in pseudo-quaternary systems (in the presence of water and partial substitution of water with both NPS) has been established. The novelty of the work with respect to possible applications has been discussed.
Effects of decabromodiphenyl ether on lead mobility and microbial toxicity in soil.
Zhang, Wei; Chen, Lei; Zhang, Rong; Lin, Kuangfei
2015-03-01
Lead (Pb) and decabromodiphenyl ether (BDE209) are the main pollutants at e-waste recycling sites (EWRSs). Focus on joint toxicological effects of the two chemicals has increasingly gained a great amount of interest. Therefore, the lab study was performed to determine the Pb mobility and microbial toxicity in a Pb-polluted soil in the presence of BDE209 for the first time. The results showed that BDE209 was barely degraded and could elicit the combined effects with Pb exposure during the entire incubation period. The exchangeable (EXCH) and carbonates fractions of Pb were transformed to organic, Fe/Mn oxides and residual fractions, and the addition of an appropriate amount (100mgkg(-1)) of BDE209 facilitated the transformation compared with Pb alone. In addition, soil microbial biomass C (Cmic), soil basal respiration (SBR) and metabolic quotient (qCO2) increased in the beginning of the experiment and then declined with the incubation period extension, and BDE209 addition might cause notable different response relative to the control. Significant correlations between EXCH or mobility factor (MF) of Pb and SBR, Cmic, or qCO2 in soil treated with BDE209 can be clearly observed. Results of the observations provide a better understanding of ecotoxicological effects of Pb and BDE209 joint exposure on indigenous microorganisms in soil at EWRSs. Copyright © 2014 Elsevier Ltd. All rights reserved.
Bombach, Petra; Nägele, Norbert; Rosell, Mònica; Richnow, Hans H; Fischer, Anko
2015-04-09
Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated, thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA), and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed insignificant carbon isotope fractionation, but low hydrogen isotope fractionation of up to +14‰ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [(13)C6]-ETBE (BACTRAP(®)s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant (13)C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation. Copyright © 2014 Elsevier B.V. All rights reserved.
Kasote, D M; Badhe, Y S; Zanwar, A A; Hegde, M V; Deshmukh, K K
2012-07-01
to investigate the hepatoprotective potential of ether insoluble phenolic components of n-butanol fraction (EPC-BF) of flaxseed against CCl(4) -induced liver damage in rats. Hepatotoxicity was induced to Wistar rats by administration of 0.2% CCl(4) in olive oil (8 mL/kg, i.p.) on the seventh day of treatment. Hepatoprotective potential of EPC-BF at doses, 250 and 500 mg/kg, p.o. was assessed through biochemical and histological parameters. EPC-BF and silymarin pretreated animal groups showed significantly decreased activities of Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and level of total bilirubin, elevated by CCl(4) intoxication. Hepatic lipid peroxidation elevated by CCl(4) intoxication were also found to be alleviated at almost normal level in the EPC-BF and silymarin pretreated groups. Histological studies supported the biochemical findings and treatment of EPC-BF at doses 250 and 500 mg/kg, p.o. was found to be effective in restoring CCl(4) -induced hepatic damage. However, EPC-BF did not show dose-dependent hepatoprotective potential. EPC-BF depicted maximum protection against CCl(4) -induced hepatic damage at lower dose 250 mg/kg than higher dose (500 mg/ kg). EPC-BF possesses the significant hepatoprotective activity against CCl(4) induced liver damage, which could be mediated through increase in antioxidant defenses.
Hassani, Solmaz; Asghari, Gholamreza; Yousefi, Hossseinali; Kazemian, Afsaneh; Rafieiean, Mahmood; Darani, Hossein Yousofi
2013-01-01
Background: Trichomonas vaginalis is considered one of the main causes of vulvovaginitis in women. Metronidazole with vast side effects is now the drug of choice for treatment of this infection. In an attempt to find an alternative drug, the effect of Eucalyptus camaldulensis on this parasite was shown in previous studies. In this investigation, the effect of different extracts of this plant on T. vaginalis in culture medium has been investigated. Materials and Methods: Five different extracts including total extract, diethyl ether, chloroform, ethyl acetate, and water fractions were prepared. The extracts were dried using vacuum rotary evaporator and then they were used for in vitro anti-trichomonas experiments. Results: Crude extract of E. camaldulensis showed 80% growth inhibition (GI) in a concentration of 12.5 mg/ml during 24 h. Diethyl ether extract in a concentration of 25 mg/ml showed 100% GI during 24 h. With ethyl acetate extract, 100% GI was detected with the minimum concentration of 12.5 mg/ml in the first 24 h. Finally, water extract in a concentration of 50 mg/ml showed 80% and 100% GI after 48 and 72 h, respectively. Conclusion: Ethyl acetate fraction is the extract which showed the highest percentage of GI (100%) with the least concentration (12.5 mg/ml) after 24 and 48 h. PMID:24516847
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goren, A.I.; Brenner, S.; Hellmann, S.
During the summer of 1984 a health survey was carried out among the population of six rural settlements, three in a polluted and three in a low polluted area. Residents of these settlements between 6 and 65 years of age filled out an ATS-NHLI health questionnaire and performed the following pulmonary function tests (PFT): FVC, FEV/sub 1/, FEV/sub 1//FVC, PEF, FEF/sub 50/, and FEF/sub 75/. A trend of higher prevalence of reported respiratory symptoms and diseases characterizes children growing up in a polluted rural as compared with a low polluted rural area. The relative risks (calculated from logistic models) formore » children from the polluted area to have sputum with cold is 2.13, cough accompanied by sputum 3.89, and for their siblings to have respiratory diseases 3.02, as compared with 1.00 in the low polluted area. A trend of lower PFT characterizes children from the polluted area, with significantly reduced PEF. The trends for adults in the two areas were similar to those for the children. The relative risks for adults from the polluted area to have sputum is 1.7 and cough accompanied by sputum 2.6, as compared with 1.0 in the low polluted area. PEF is significantly lower among adults from the polluted area, while FEF/sub 50/ and FEF/sub 75/ are lower (not significantly) among adults from the low polluted area.« less
Babaei, Ali Akbar; Ghanbari, Farshid; Yengejeh, Reza Jalilzadeh
2017-04-01
Photoelectro-Fenton (PEF) was carried out for concurrent removals of inorganic and organic pollutants with simultaneous applications of two different anodes (iron and copper). Cadmium and Direct Orange 26 (DO26) were selected as samples of the contaminants of textile wastewater and influential parameters (pH, current density, H 2 O 2 dosage and electrolysis time) of PEF were evaluated on Cd and DO26 removals. Both mechanisms of coagulation and oxidation affected the removal of both pollutants. Optimal conditions were achieved with pH = 4.0, current density of 5 mA/cm 2 , 3 mM H 2 O 2 and 40 min electrolysis time, and under these conditions, the dye was completely removed and the Cd removal efficiency was about 80%. Unlike H 2 O 2 , persulfate had no scavenging effect in high dosages. The effects of different anions and two matrixes (tap water and wastewater) on Cd and dye removals were investigated. The results showed that decolorization was reduced by the phosphate and nitrate ions while chloride ion accelerated the decolorization rate. In terms of Cd removal, no significant change was observed in the presence of the anions except for phosphate ion. The sludge of PEF was assessed by Fourier transform infrared, field emission scanning electron microscope and energy-dispersive X-ray spectroscopy.
Lung Function Impact from Working in the Pre-Revolution Libyan Quarry Industry
Draid, Marwan M.; Ben-Elhaj, Khaled M.; Ali, Ashraf M.; Schmid, Kendra K.; Gibbs, Shawn G.
2015-01-01
The purpose of this study was to determine the lung impact from working within the Libyan quarry industry, and if the length of work impacted the degree of degradation. Eighty three workers from eight silica quarries in the Nafusa Mountains of Libya opted to participate. These quarries were working the upper cretaceous geological structure. Eighty-five individuals who lived in Gharyan City with no affiliation to quarry operations participated as controls. Spirometry variables evaluated were Forced Vital Capacity (FVC), Forced Expiratory Volume at 1.0 second (FEV1), FVC/FEV1 and Peak Expiratory Flow (PEF). Control and exposed groups had no differences in terms of height, weight, or smoking status (p = 0.18, 0.20, 0.98, respectively). Prior to adjustment for other variables, FVC, FEV1, and PEF are all significantly lower in the exposed group (p = 0.003, 0.009, 0.03, respectively). After adjustment for age, height, weight, and smoking status, there remain significant differences between the control and exposed groups for FVC, FEV1, and PEF. This analysis demonstrated that exposure to quarry dust has a detrimental effect on lung function, and that pre-revolution Libyan quarry workers were being exposed. This study shows that any exposure is harmful, as the reduction in lung function was not significantly associated with years of exposure. PMID:25961801
Air pollution and fuel vapour induced changes in lung functions: are fuel handlers safe?
Chawla, Anuj; Lavania, A K
2008-01-01
Automobile exhaust derived air pollutants have become a major health hazard. Coupled with the inhalation of fuel vapour, as occurs in petrol station workers, this may lead to significant impairment of lung function. Spirometric lung functions were studied in 58 petrol station workers to examine this possibility. The forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory flow 25%-75% (FEF25-75) and peak expiratory flow (PEF) were recorded and analysed separately for smokers and non-smokers. The workers were divided into 5 groups for analysis of data based on the number of years of work in the petrol pumps. Outdoor air analysis was also carried out. The FVC, FEV1 and PEF declined significantly with increasing years of work in petrol stations in both smokers and non-smokers. Smoking as an independent variable was found to affect the FEV1 significantly but not FVC or PEF. The FEF25-75 was found to be the most affected spirometric value with a significant reduction with increasing years of work. Smoking as such did not affect it. Oxides of nitrogen (NOx), suspended particulate matter (SPM) and particulate matter less than 10 microns (PM10) in outdoor air were higher than the national ambient air quality standards. Exposure to automobile exhaust and fuel vapour impairs lung function in a time-dependent manner. Cigarette smoking appears to accelerate the decline.
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Shimizu, Atsushi; Sano, Hiroyuki; Kato, Kazuhiro; Mikami, Masaaki; Ueda, Yasuto; Tatsukawa, Toshiyuki; Ohga, Hideki; Yamasaki, Akira; Igishi, Tadashi; Kitano, Hiroya; Shimizu, Eiji
2015-01-01
Light detection and ranging (LIDAR) can estimate daily volumes of sand dust particles from the East Asian desert to Japan. The objective of this study was to investigate the relationship between sand dust particles and pulmonary function, and respiratory symptoms in adult patients with asthma. One hundred thirty-seven patients were included in the study. From March 2013 to May 2013, the patients measured their morning peak expiratory flow (PEF) and kept daily lower respiratory symptom diaries. A linear mixed model was used to estimate the correlation of the median daily levels of sand dust particles, symptoms scores, and PEF. A heavy sand dust day was defined as an hourly concentration of sand dust particles of >0.1 km−1. By this criterion, there were 8 heavy sand dust days during the study period. Elevated sand dust particles levels were significantly associated with the symptom score (0.04; 95% confidence interval (CI); 0.03, 0.05), and this increase persisted for 5 days. There was no significant association between PEF and heavy dust exposure (0.01 L/min; 95% CI, −0.62, 0.11). The present study found that sand dust particles were significantly associated with worsened lower respiratory tract symptoms in adult patients with asthma, but not with pulmonary function. PMID:26501307
El-Ghenymy, Abdellatif; Garrido, José Antonio; Centellas, Francesc; Arias, Conchita; Cabot, Pere Lluís; Rodríguez, Rosa María; Brillas, Enric
2012-04-05
The mineralization of sulfanilic acid has been studied by electro-Fenton (EF) and photoelectro-Fenton (PEF) reaction with UVA light using an undivided electrochemical cell with a boron-doped diamond (BDD) anode and an air diffusion cathode able to generate H(2)O(2). Organics were then oxidized by hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between generated H(2)O(2) and added Fe(2+). The UVA irradiation in PEF enhanced the production of hydroxyl radicals in the bulk, accelerating the removal of organics and photodecomposed intermediates like Fe(III)-carboxylate complexes. Partial decontamination of 1.39 mM sulfanilic acid solutions was achieved by EF until 100 mA cm(-2) at optimum conditions of 0.4 mM Fe(2+) and pH 3.0. The increase in current density and substrate content led to an almost total mineralization. In contrast, the PEF process was more powerful, yielding almost complete mineralization in less electrolysis time under comparable conditions. The kinetics for sulfanilic acid decay always followed a pseudo-first-order reaction. Hydroquinone and p-benzoquinone were detected as aromatic intermediates, whereas acetic, maleic, formic, oxalic, and oxamic acids were identified as generated carboxylic acids. NH(4)(+) ion was preferentially released in both treatments, along with NO(3)(-) ion in smaller proportion.
Asher, W.E.; Luo, W.; Campo, K.W.; Bender, D.A.; Robinson, K.W.; Zogorski, J.S.; Pankow, J.F.
2007-01-01
Position-dependent concentrations of trichloroethylene and methyl-tert-butyl ether are considered for a 2.81-km section of the Aberjona River in Massachusetts, USA. This river flows through Woburn and Winchester (Massachusetts, USA), an area that is highly urbanized, has a long history of industrial activities dating to the early 1800s, and has gained national attention because of contamination from chlorinated solvent compounds in Woburn wells G and H. The river study section is in Winchester and begins approximately five stream kilometers downstream from the Woburn wells superfund site. Approximately 300 toxic release sites are documented in the watershed upstream from the terminus of the study section. The inflow to the river study section is considered one source of contamination. Other sources are the atmosphere, a tributary flow, and groundwater flows entering the river; the latter are categorized according to stream zone (1, 2, 3, etc.). Loss processes considered include outflows to groundwater and water-to-atmosphere transfer of volatile compounds. For both trichloroethylene and methyl-rerf-butyl ether, degradation is neglected over the timescale of interest. Source apportionment fractions with assigned values ??inflow, ??1, ??2, ??3, etc. are tracked by a source apportionment model. The strengths of the groundwater and tributary sources serve as fitting parameters when minimizing a reduced least squares statistic between water concentrations measured during a synoptic study in July 2001 versus predictions from the model. The model fits provide strong evidence of substantial unknown groundwater sources of trichloroethylene and methyl-tert-butyl ether amounting to tens of grams per day of trichloroethylene and methyl-tert-butyl ether in the river along the study section. Modeling in a source apportionment manner can be useful to water quality managers allocating limited resources for remediation and source control. ?? 2007 SETAC.
Lemieux, Christine L; Long, Alexandra S; Lambert, Iain B; Lundstedt, Staffan; Tysklind, Mats; White, Paul A
2015-02-03
Here we evaluate the excess lifetime cancer risk (ELCR) posed by 10 PAH-contaminated soils using (i) the currently advocated, targeted chemical-specific approach that assumes dose additivity for carcinogenic PAHs and (ii) a bioassay-based approach that employs the in vitro mutagenic activity of the soil fractions to determine levels of benzo[a]pyrene equivalents and, by extension, ELCR. Mutagenic activity results are presented in our companion paper.1 The results show that ELCR values for the PAH-containing fractions, determined using the chemical-specific approach, are generally (i.e., 8 out of 10) greater than those calculated using the bioassay-based approach; most are less than 5-fold greater. Only two chemical-specific ELCR estimates are less than their corresponding bioassay-derived values; differences are less than 10%. The bioassay-based approach, which permits estimation of ELCR without a priori knowledge of mixture composition, proved to be a useful tool to evaluate the chemical-specific approach. The results suggest that ELCR estimates for complex PAH mixtures determined using a targeted, chemical-specific approach are reasonable, albeit conservative. Calculated risk estimates still depend on contentious PEFs and cancer slope factors. Follow-up in vivo mutagenicity assessments will be required to validate the results and their relevance for human health risk assessment of PAH-contaminated soils.
Suzuki, Ryuichiro; Hasuike, Yuka; Hirabayashi, Moeka; Fukuda, Tatsuo; Okada, Yoshihito; Shirataki, Yoshiaki
2013-10-01
We demonstrate that NMR-based metabolomics studies can be used to identify xanthine oxidase-inhibitory compounds in the diethyl ether soluble fraction prepared from a methanolic extract of Sophora flavescens. Loading plot analysis, accompanied by direct comparison of 1H NMR spectraexhibiting characteristic signals, identified compounds exhibiting inhibitory activity. NMR analysis indicated that these characteristic signals were attributed to flavanones such as sophoraflavanone G and kurarinone. Sophoraflavanone G showed inhibitory activity towards xanthine oxidase in an in vitro assay.
Dron, Julien; Garcia, Rosa; Millán, Esmeralda
2002-07-19
A procedure for determination of methyl tert.-butyl ether (MTBE) in water by headspace solid-phase microextraction (HS-SPME) has been developed. The analysis was carried out by gas chromatography with flame ionization detection. The extraction procedure, using a 65-microm poly(dimethylsiloxane)-divinylbenzene SPME fiber, was optimized following experimental design. A fractional factorial design for screening and a central composite design for optimizing the significant variables were applied. Extraction temperature and sodium chloride concentration were significant variables, and 20 degrees C and 300 g/l were, respectively chosen for the best extraction response. With these conditions, an extraction time of 5 min was sufficient to extract MTBE. The calibration linear range for MTBE was 5-500 microg/l and the detection limit 0.45 microg/l. The relative standard deviation, for seven replicates of 250 microg/l MTBE in water, was 6.3%.
Uematsu, Y; Hirata, K; Suzuki, K; Iida, K; Saito, K
2001-02-01
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GC-MS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1 mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl anti BFDGE.HCl.H2O at a level of 1.5 mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.
Aiello, Anna; Fattorusso, Ernesto; Menna, Marialuisa; Vitalone, Rocco; Schröder, Heinz C.; Müller, Werner E. G.
2011-01-01
Mumijo is a widely used traditional medicine, especially in Russia, Altai Mountains, Mongolia, Iran Kasachstan and in Kirgistan. Mumijo preparations have been successfully used for the prevention and treatment of infectious diseases; they display immune-stimulating and antiallergic activity as well. In the present study, we investigate the chemical composition and the biomedical potential of a Mumijo(-related) product collected from the Antarctica. The yellow material originates from the snow petrels, Pagodroma nivea. Extensive purification and chemical analysis revealed that the fossil samples are a mixture of glycerol derivatives. In vitro experiments showed that the Mumijo extract caused in cortical neurons a strong neuroprotective effect against the apoptosis-inducing amyloid peptide fragment β-fragment 25–35 (Aβ25–35). In addition, the fraction rich in glycerol ethers/wax esters displayed a significant growth-promoting activity in permanent neuronal PC12 cells. It is concluded that this new Mumijo preparation has distinct and marked neuroprotective activity, very likely due to the content of glycerol ether derivatives. PMID:18996940
40 CFR Table 6 to Subpart Jj of... - VHAP of Potential Concern
Code of Federal Regulations, 2011 CFR
2011-07-01
... glycol butyl ether, ethylene glycol ethyl ether (2-ethoxy ethanol), ethylene glycol hexyl ether, ethylene..., ethylene glycol mono-2-ethylhexyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether... glycol propyl ether, triethylene glycol butyl ether, triethylene glycol ethyl ether, triethylene glycol...
Antioxidant and antimutagenic potential of Psidium guajava leaf extracts.
Zahin, Maryam; Ahmad, Iqbal; Aqil, Farrukh
2017-04-01
Fruits, vegetables and medicinal herbs rich in phenolics antioxidants contribute toward reduced risk of age-related diseases and cancer. In this study, Psidium guajava leaf extract was fractionated in various organic solvents viz. petroleum ether, benzene, ethyl acetate, ethanl and methanol and tested for their antioxidant and antimutagenic properties. Methanolic fraction showed maximum antioxidant activity comparable to ascorbic acid and butylated hydroxyl toluene (BHT) as tested by DPPH free radical scavenging, phosphomolybdenum, FRAP (Fe3 + reducing power) and CUPRAC (cupric ions (Cu 2+ ) reducing ability) assays. The fraction was analyzed for antimutagenic activities against sodium azide (NaN 3 ), methylmethane sulfonate (MMS), 2-aminofluorene (2AF) and benzo(a)pyrene (BP) in Ames Salmonella tester strains. The methanol extracted fraction at 80 μg/ml concentration inhibited above 70% mutagenicity. Further, phytochemical analysis of methanol fraction that was found to be most active revealed the presence of nine major compounds by gas chromatography-mass spectrometry (GC-MS). This data suggests that guava contains high amount of phenolics responsible for broad-spectrum antimutagenic and antioxidant properties in vitro and could be potential candidates to be explored as modern phytomedicine.
Ramjan, Ali; Hossain, Marjan; Runa, Jannatul Ferdous; Md, Hasanuzzaman; Mahmodul, Islam
2014-11-01
The present study is aimed to investigate in vitro thrombolytic activity of three Bangladeshi medicinal plants Averrhoa bilimbi (Oxalidiaceae), Clerodendrum viscosum (Verbanaceae) and Drynaria quercifolia (Polypodiaceae). Each the plant was extracted with methanol at room temperature and the concentrated methanolic extracts (MEF) were fractionated by the modified Kupchan partitioning method to render pet-ether soluble fraction (PESF), carbon tetrachloride soluble fraction (CTSF), chloroform soluble fraction (CSF) and aqueous soluble fraction (AQSF). To observe their thrombolytic potential, a prompt and swift method was involved where streptokinase and water were used as positive and negative control, respectively. Among the three plants, AQSF and PESF of D. quercifolia with CTSF of C. viscosum exhibited highest thrombolytic activity by clot lysis of 34.38%, 34.27% and 28.64%, respectively. Among other extracts A. bilimbi, C. viscosun and D.quercifolia showed significant percentage (%) of clot lysis compared to standard streptokinase (41.05%) while the negative control water revealed 3.31 % lysis of clot. From our findings it is observed that all the plants revealed remarkable thrombolytic activity. Therefore, steps should be taken to observe in vivo clot dissolving potential and to isolate active component(s) of these extracts.
Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess
2015-01-01
Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time.
Tofighi, Zahra; Molazem, Maryam; Doostdar, Behnaz; Taban, Parisa; Shahverdi, Ahmad Reza; Samadi, Nasrin; Yassa, Narguess
2015-01-01
Rosa damascena, Tripleurospermum disciforme and Securigera securidaca were used as disinfectant agents and for treatment of some disease in folk medicine of Iran. The antimicrobial effects of different fractions of seeds extract of S. securidaca, petals extract of R. damascena and aerial parts extract of T. disciforme were examined against some gram positive, gram negative and fungi by cup plate diffusion method. The petroleum ether and chloroform fractions of S. securidaca showed antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa, while its methanol fraction had no antibacterial effects. R. damascena petals extract demonstrated antibacterial activities against Bacillus cereus, Staphylococcus epidermidis, S. aureus and Pseudomonas aeruginosa. T. disciforme aerial parts extract exhibited antimicrobial effects only against S. aureus and S. epidermidis. None of the fractions had any antifungal activities. Therefore, present study confirmed utility of these plants as disinfectant agents. Six flavonoids were isolated from T. disciforme: Luteolin, Quercetin-7-O-glucoside, Kaempferol, Kaempferol-7-O-glucoside, Apigenin and Apigenin-7-O-glucoside. The flavonoids and the antimicrobial activity of T. disciforme are reported for the first time. PMID:25561928
Study of Antibacterial Activity and Bacteriology of Latex from Asclepias syriaca L
McCay, Steven; Mahlberg, Paul
1973-01-01
Whole and fractionated latex of Asclepias syriaca was tested for antimicrobial or growth-promoting activity with 16 genera and species of bacteria. Latex and extracted fractions (distilled water, acetic acid, sodium bicarbonate, sulfuric acid, and ethyl ether) possessed no detectable antimicrobial activity. Comparison of growth curves of selected bacteria incubated with serum and rubber fractions, as well as controls, revealed no detectable inhibition of growth, except for a slight inhibitory response to autoclaved serum. Most bacteria were capable of utilizing latex for a substrate as indicated by the increased growth rate in the exponential phase. The stationary phase was entered simultaneously by both the treated cultures and the controls. Various bacteria cultured in a litmus latex mixture yielded populations which ranged from <104 organisms/ml for Lactobacillus casei, Staphylococcus aureus and Micrococcus lysodeikticus to 1.1 × 1010 organisms/ml for Clostridium acetobutylicum. Whole latex, as well as the serum and rubber fractions, support the growth of various bacteria, but under field conditions there is no evidence for systemic infection of this type of cell by bacteria. PMID:4790590
Dhouafli, Zohra; Ben Jannet, Hichem; Mahjoub, Borhane; Leri, Manuela; Guillard, Jérôme; Saidani Tounsi, Moufida; Stefani, Massimo; Hayouni, El Akrem
2017-12-29
Mounting evidence indicates free radicals as toxic species causing damage to human cells leading to the pathogenesis of many diseases such as neurodegenerative disease. Plant derived antioxidants are considered as promising strategy to prevent free radical toxicity. In this study, the crude extract (CE), 50%MeOH, Petroleum Ether (PE) and Ethyl acetate (EA) fractions of Lawsonia inermis leaves were investigated for their antioxidant activity and their ability to counteract amyloid-β 42 (Aβ 42 ) aggregation. Elution of the most bioactive fraction (EA) on silica gel column chromatography led to six sub-fractions. The most active sub-fraction (1) was further resolved on silica gel column chromatography. A new compound with powerful antioxidant and anti-Aβ 42 aggregation properties was purified and characterised by spectroscopic methods as 1,2,4-trihydroxynaphthalene-2-O-β-D-glucopyranoside (THNG). This finding suggests that the antioxidant and anti-Aβ 42 aggregation activities of L. inermis leaves are strongly correlated to this compound.
[Effects of anxiety on cardiorespiratory function].
Dimitriev, D A; Saperova, E V; Dimitriev, A D; Karpenko, Iu D
2014-01-01
The present study was undertaken to investigate the effect of anxiety on pulmonary function parameters and respiratory sinus arrhythmia (RSA) in healthy people under real-life conditions. This study consisted of two interrelated parts. During the first stage, eighty healthy students were examined in the following sequence: recording of heart rate variability (HRV) and respiration parameters at rest and shortly before real life stress. In a longitudinal study (the second stage), we assessed the profile of cardiorespiratory activity over 50 days in ten healthy women. Pulmonary function parameters like breath rate, tidal volume, forced expiratory volume in ones (FEV1), peak expiratory flow (PEF), forced expired flow at 25%, 50%, 75% of FVC, forced expired flow from 25-75% of FVC (FEF25-75%) and HRV measures (SDNN, RMSSD, pNN50, LF, HF, HFnorm, LF/HF ratio) of all subjects were tested. State anxiety was measured by Spielberger state anxiety inventory. Higher levels of state anxiety were associated with higher levels of breath rate, tidal volume and reduced HRV parameters, especially indicators of the RSA (HF and HFnorm) at baseline. These changes depend on the category of state anxiety: the group of students with a qualitative increase in state anxiety before examination has increased level of FEV1, PEF, forced expired flow at 25%, 50%, 75% of FVC, FEF25-75%. Less reactive students have no difference in respiratory parameters. We found a strong negative correlation between the level of HF at rest and state anxiety scores before examination. Longitudinal study found a negative correlation between RSA parameters and PEF, positive correlation between state anxiety and PEF of the majority those surveyed, except for two women with low levels of state anxiety and RSA indicators were in a narrow range. The variations of cardiorespiratory parameters during a longitudinal study depend on the changes of state anxiety. The higher level of state anxiety was associated with significant changes in RSA and the respiratory parameters. These results lend strong support to the notion that parasympathetic function is a critical physiological component of emotional processes.
Thrivikraman, Greeshma; Lee, Poh S; Hess, Ricarda; Haenchen, Vanessa; Basu, Bikramjit; Scharnweber, Dieter
2015-10-21
The influences of physical stimuli such as surface elasticity, topography, and chemistry over mesenchymal stem cell proliferation and differentiation are well investigated. In this context, a fundamentally different approach was adopted, and we have demonstrated the interplay of inherent substrate conductivity, defined chemical composition of cellular microenvironment, and intermittent delivery of electric pulses to drive mesenchymal stem cell differentiation toward osteogenesis. For this, conducting polyaniline (PANI) substrates were coated with collagen type 1 (Coll) alone or in association with sulfated hyaluronan (sHya) to form artificial extracellular matrix (aECM), which mimics the native microenvironment of bone tissue. Further, bone marrow derived human mesenchymal stem cells (hMSCs) were cultured on these moderately conductive (10(-4)-10(-3) S/cm) aECM coated PANI substrates and exposed intermittently to pulsed electric field (PEF) generated through transformer-like coupling (TLC) approach over 28 days. On the basis of critical analysis over an array of end points, it was inferred that Coll/sHya coated PANI (PANI/Coll/sHya) substrates had enhanced proliferative capacity of hMSCs up to 28 days in culture, even in the absence of PEF stimulation. On the contrary, the adopted PEF stimulation protocol (7 ms rectangular pulses, 3.6 mV/cm, 10 Hz) is shown to enhance osteogenic differentiation potential of hMSCs. Additionally, PEF stimulated hMSCs had also displayed different morphological characteristics as their nonstimulated counterparts. Concomitantly, earlier onset of ALP activity was also observed on PANI/Coll/sHya substrates and resulted in more calcium deposition. Moreover, real-time polymerase chain reaction results indicated higher mRNA levels of alkaline phosphatase and osteocalcin, whereas the expression of other osteogenic markers such as Runt-related transcription factor 2, Col1A, and osteopontin exhibited a dynamic pattern similar to control cells that are cultured in osteogenic medium. Taken together, our experimental results illustrate the interplay of multiple parameters such as substrate conductivity, electric field stimulation, and aECM coating on the modulation of hMSC proliferation and differentiation in vitro.
Characterization and origin of polar dissolved organic matter from the Great Salt Lake
Leenheer, J.A.; Noyes, T.I.; Rostad, C.E.; Davisson, M.L.
2004-01-01
Polar dissolved organic matter (DOM) was isolated from a surface-water sample from the Great Salt Lake by separating it from colloidal organic matter by membrane dialysis, from less-polar DOM fractions by resin sorbents, and from inorganic salts by a combination of sodium cation exchange followed by precipitation of sodium salts by acetic acid during evaporative concentration. Polar DOM was the most abundant DOM fraction, accounting for 56% of the isolated DOM. Colloidal organic matter was 14C-age dated to be about 100% modern carbon and all of the DOM fractions were 14C-age dated to be between 94 and 95% modern carbon. Average structural models of each DOM fraction were derived that incorporated quantitative elemental and infrared, 13C-NMR, and electrospray/mass spectrometric data. The polar DOM model consisted of open-chain N-acetyl hydroxy carboxylic acids likely derived from N-acetyl heteropolysaccharides that constituted the colloidal organic matter. The less polar DOM fraction models consisted of aliphatic alicyclic ring structures substituted with carboxyl, hydroxyl, ether, ester, and methyl groups. These ring structures had characteristics similar to terpenoid precursors. All DOM fractions in the Great Salt Lake are derived from algae and bacteria that dominate DOM inputs in this lake.
Mecozzi, M; Amici, M; Romanelli, G; Pietrantonio, E; Deluca, A
2002-07-19
This paper reports an analytical procedure based on ultrasound to extract lipids in marine mucilage samples. The experimental conditions of the ultrasound procedure (solvent and time) were identified by a FT-IR study performed on different standard samples of lipids and of a standard humic sample, before and after the sonication treatment. This study showed that diethyl ether was a more suitable solvent than methanol for the ultrasonic extraction of lipids from environmental samples because it allowed to minimize the possible oxidative modifications of lipids due to the acoustic cavitation phenomena. The optimized conditions were applied to the extraction of total lipid amount in marine mucilage samples and TLC-flame ionization detection analysis was used to identify the relevant lipid sub-fractions present in samples.
Hofmann, Michael A.
2006-11-14
The present invention is directed to sulfonimide-containing polymers, specifically sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, and processes for making the sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, for use conductive membranes and fuel cells.
Detection of 1-nitropyrene in yakitori (grilled chicken).
Kinouchi, T; Tsutsui, H; Ohnishi, Y
1986-01-01
Pieces of raw chicken with or without a marinating sauce were grilled over a city gas flame, extracted with benzene-ethanol (4:1) by ultrasonication and fractionated into diethyl ether-soluble neutral, acidic and basic fractions. The mutagenicity of these fractions was measured with Salmonella typhimurium strains TA100, TA98, TA98NR and TA98/1,8-DNP6 in the presence and absence of a 9000 X g post-mitochondrial supernatant from Aroclor 1254-treated Sprague-Dawley rat liver (S9 mix). The basic fraction of yakitori without the sauce was more mutagenic than the other fractions for S. typhimurium strain TA98 in the presence of S9 mix. This is probably due to the presence of amino acid or protein pyrolysates. However, when the chicken was grilled with the sauce, the basic fraction showed lower mutagenicity for strain TA98 in the presence of S9 mix than did the same fraction without the sauce. The neutral fraction of yakitori with sauce showed high mutagenicity for strain TA98 in the absence of S9 mix, but low mutagenicity for strains TA98NR and TA98/1,8-DNP6, suggesting that this fraction might contain nitropyrenes (NPs). The neutral fraction of yakitori was analyzed by high-performance liquid chromatography (HPLC). The neutral fraction of the chicken grilled with the sauce for 3, 5 and 7 min contained 3.8, 19 and 43 ng, respectively, of 1-NP per gram of yakitori accounting for 3.0, 2.7 and 1.3%, respectively, of the total mutagenicity.(ABSTRACT TRUNCATED AT 250 WORDS)
In Vitro Enzymatic Depolymerization of Lignin with Release of Syringyl, Guaiacyl, and Tricin Units
Gall, Daniel L.; Kontur, Wayne S.; Lan, Wu; Kim, Hoon; Li, Yanding; Ralph, John
2017-01-01
ABSTRACT New environmentally sound technologies are needed to derive valuable compounds from renewable resources. Lignin, an abundant polymer in terrestrial plants comprised predominantly of guaiacyl and syringyl monoaromatic phenylpropanoid units, is a potential natural source of aromatic compounds. In addition, the plant secondary metabolite tricin is a recently discovered and moderately abundant flavonoid in grasses. The most prevalent interunit linkage between guaiacyl, syringyl, and tricin units is the β-ether linkage. Previous studies have shown that bacterial β-etherase pathway enzymes catalyze glutathione-dependent cleavage of β-ether bonds in dimeric β-ether lignin model compounds. To date, however, it remains unclear whether the known β-etherase enzymes are active on lignin polymers. Here we report on enzymes that catalyze β-ether cleavage from bona fide lignin, under conditions that recycle the cosubstrates NAD+ and glutathione. Guaiacyl, syringyl, and tricin derivatives were identified as reaction products when different model compounds or lignin fractions were used as substrates. These results demonstrate an in vitro enzymatic system that can recycle cosubstrates while releasing aromatic monomers from model compounds as well as natural and engineered lignin oligomers. These findings can improve the ability to produce valuable aromatic compounds from a renewable resource like lignin. IMPORTANCE Many bacteria are predicted to contain enzymes that could convert renewable carbon sources into substitutes for compounds that are derived from petroleum. The β-etherase pathway present in sphingomonad bacteria could cleave the abundant β–O–4-aryl ether bonds in plant lignin, releasing a biobased source of aromatic compounds for the chemical industry. However, the activity of these enzymes on the complex aromatic oligomers found in plant lignin is unknown. Here we demonstrate biodegradation of lignin polymers using a minimal set of β-etherase pathway enzymes, the ability to recycle needed cofactors (glutathione and NAD+) in vitro, and the release of guaiacyl, syringyl, and tricin as depolymerized products from lignin. These observations provide critical evidence for the use and future optimization of these bacterial β-etherase pathway enzymes for industrial-level biotechnological applications designed to derive high-value monomeric aromatic compounds from lignin. PMID:29180366
Publications of the Penobscot Experiment Forest, 1950-2010
Laura S. Kenefic; John C. Brissette
2014-01-01
This bibliography includes all journal articles, technical reports, proceedings, U.S. Forest Service publications, and theses published about or using data from the Penobscot Experimental Forest (PEF) during its first 60 years.
Guionet, Alexis; Hosseini, Bahareh; Akiyama, Hidenori; Hosano, Hamid
2018-04-25
The green algae Botryococcus braunii produces a high amount of extracellular hydrocarbon, making it a promising algae in the field of bio-fuels production. As it mainly produces squalene like hydrocarbons, cosmetic industries are also interested in its milking. Pulsed electric fields (PEF) are an innovative method allowing oil extraction from micro-algae. In common algae accumulating hydrocarbon inside cytoplasm (Chlorella vulgaris, Nannochloropsis sp., etc), electric fields can destroy cell membranes, allowing the release of hydrocarbon. However, for B.braunii, hydrocarbons adhere to the cell wall outside of cells as a matrix. In a previous article we reported that electric fields can unstick cells from a matrix, allowing hydrocarbon harvesting. In this work, we deeper investigated this phenomenon of cell hatching by following 2 parameters: the conductivity of the medium and the cultivation duration of the culture. Cell hatching is accurately evaluated by both microscopic and macroscopic observations. For high conductivity and a short time of cultivation, almost no effect is observed even after up to 1000 PEF pulses are submitted to the cells. While lower conductivity and a longer cultivation period allow strong cell hatching after 200 PEF pulses are applied to the cells. We identify 2 new crucial parameters, able to turn the method from inefficient to very efficient. It might help companies to save energy and money in case of mass production. Copyright © 2018. Published by Elsevier B.V.
Van de Weg, F B; Van der Windt, D A W M
2005-12-01
The objectives were to investigate the effect of three different interface types on consumer satisfaction and perceived problems among trans-tibial amputees in the Netherlands. A postal questionnaire (based on the Prosthesis Evaluation Questionnaire) was sent to 353 patients. Responders were classified in three groups of interface types: polyethylene foam (PEF) inserts, silicone liners (SIL), and polyurethane liners (PUL). Differences concerning satisfaction and problems between interface types were computed and adjusted for potential confounding by age, gender, reason for amputation and time since first prosthesis. A total of 220 patients responded (62%). Patients wearing liners reported a significantly poorer durability and higher maintenance time compared with patients using PEF inserts. Sum-scores for satisfaction or problems did not show any significant differences between groups. Analysis of individual items showed a significant difference only for satisfaction with sitting and with walking on uneven terrain in favour of PEF inserts. In contrast to most studies, interface type was included as a possible determinant of customer use, satisfaction, and perceived problems. The perceived differences between the three suspension types are to a large extent small and non-significant. The findings do not support liner prescription as a matter of course for all trans-tibial amputees. A careful analysis of patients' preferences should be made to determine the best course of action. Further studies, preferably prospective, need to be conducted to determine which systems are most comfortable and offer least complaints.
Short-term effect of winter air pollution on respiratory health of asthmatic children in Paris.
Segala, C; Fauroux, B; Just, J; Pascual, L; Grimfeld, A; Neukirch, F
1998-03-01
There is controversy as to whether low levels of air pollution affect the symptoms and lung function in asthma. We addressed this by examining the short-term effects of winter air pollution on childhood asthma in Paris. We performed a 6 month follow-up of 84 medically diagnosed asthmatic children classified into two groups of severity. The outcomes included incidence and prevalence of asthma attacks, symptoms and use of supplementary beta2-agonists, peak expiratory flow (PEF) value and its variability. The statistical analysis controlled the lack of independence between daily health outcomes, trends and meteorology. Air pollution was associated with an increase in reports and duration of asthma attacks and asthma-like symptoms in mild asthmatic children. The strongest association was the risk of asthma attack for an increase of 50 microg x m(-3) of sulphur dioxide (SO2) on the same day (odds ratio (OR)=2.86). Maximum reduction in morning peak expiratory flow (PEF) (5%) and maximum increase in PEF variability (2%) were observed at a lag of 3 days for an increase of 50 microg x m(-3) of SO2 in the subgroup of mild asthmatics receiving no regular inhaled medication. In moderate asthmatic children, the duration of supplementary beta2-agonist use was strongly associated with air pollution. The general pattern of our results provides evidence of the effect of the low levels of air pollution encountered in Western Europe on symptoms and lung function in childhood asthma.
Al, Behcet; Yildirim, Cuma; Zengin, Suat; Cavdar, Murat; Togun, Ismail
2009-06-01
To determine the effect of chronic carbon-monoxide (CO) exposure on blood carboxy-hemoglobin (COHb) values in grill-kebab chefs, and if there is any subsequent airway obstruction. The study was carried out in Sahinbey Hospital, Medical School of Gaziantep University, Gaziantep, Turkey, between March 2007 and November 2007. Forty male grill-kebab chefs, working in restaurants for at least 3 years, and 48 non-smoker, male healthy volunteers were gathered for this study. The ages, body mass indexes (BMI), blood pressure (BP), COHb, N-terminal pro brain natriuretic peptide (NT-proBNP), and peak expiratory flow (PEF) values of the grill-kebab chefs and controls was measured. Statistical analysis was carried out using the SSPS 13.0 software. The average age for the study group was 33.0 +/- 9.1, and for the control group was 34.7+/- 6.5 years. The average occupation time for the study group was 16.1+/-7.3 years. The clinical attributes, ages, BMI, BP, and NT-proBNP values of both groups were similar. The COHb (6.5+/-1.5/2.0+/-1.1%) values were higher in grill-kebab chefs compared with the control group. The NT-proBNP values were determined as normal (<60 microg/L) in both groups. A higher decrease in PEF speed (average: 65.1/7.1 L/min) was recorded in the grill-kebab chefs. Chronic exposure to CO decreases PEF, with narrowing of the airway in grill-kebab chefs.
Flores, Nelly; Thiam, Abdoulaye; Rodríguez, Rosa María; Centellas, Francesc; Cabot, Pere Lluís; Garrido, José Antonio; Brillas, Enric; Sirés, Ignasi
2017-03-01
Acidic solutions of trans-cinnamic acid at pH 3.0 have been comparatively treated by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF), and photoelectro-Fenton (PEF). The electrolytic experiments were carried out with a boron-doped diamond (BDD)/air-diffusion cell. The substrate was very slowly abated by AO-H 2 O 2 because of its low reaction rate with oxidizing • OH produced from water discharge at the BDD anode. In contrast, its removal was very rapid and at similar rate by EF and PEF due to the additional oxidation by • OH in the bulk, formed from Fenton's reaction between cathodically generated H 2 O 2 and added Fe 2+ . The AO-H 2 O 2 treatment yielded the lowest mineralization. The EF process led to persistent final products like Fe(III) complexes, which were quickly photolyzed upon UVA irradiation in PEF to give an almost total mineralization with 98 % total organic carbon removal. The effect of current density and substrate concentration on all the mineralization processes was examined. Gas chromatography-mass spectrometry (GC-MS) analysis of electrolyzed solutions allowed identifying five primary aromatics and one heteroaromatic molecule, whereas final carboxylic acids like fumaric, acetic, and oxalic were quantified by ion exclusion high-performance liquid chromatography (HPLC). From all the products detected, a degradation route for trans-cinnamic acid is proposed.
Timmermans, R A H; Nierop Groot, M N; Nederhoff, A L; van Boekel, M A J S; Matser, A M; Mastwijk, H C
2014-03-03
Pulsed electrical field (PEF) technology can be used for the inactivation of micro-organisms and therefore for preservation of food products. It is a mild technology compared to thermal pasteurization because a lower temperature is used during processing, leading to a better retention of the quality. In this study, pathogenic and spoilage micro-organisms relevant in refrigerated fruit juices were studied to determine the impact of process parameters and juice composition on the effectiveness of the PEF process to inactivate the micro-organisms. Experiments were performed using a continuous-flow PEF system at an electrical field strength of 20 kV/cm with variable frequencies to evaluate the inactivation of Salmonella Panama, Escherichia coli, Listeria monocytogenes and Saccharomyces cerevisiae in apple, orange and watermelon juices. Kinetic data showed that under the same conditions, S. cerevisiae was the most sensitive micro-organism, followed by S. Panama and E. coli, which displayed comparable inactivation kinetics. L. monocytogenes was the most resistant micro-organism towards the treatment conditions tested. A synergistic effect between temperature and electric pulses was observed at inlet temperatures above 35 °C, hence less energy for inactivation was required at higher temperatures. Different juice matrices resulted in a different degree of inactivation, predominantly determined by pH. The survival curves were nonlinear and could satisfactorily be modeled with the Weibull model. Copyright © 2013 Elsevier B.V. All rights reserved.
Occupational asthma in the furniture industry: is it due to styrene?
Oner, Ferda; Mungan, Dilşad; Numanoglu, Numan; Demirel, Yavuz
2004-01-01
Styrene, a volatile monomer, has been reported as a cause of occupational asthma in a few case reports. The aim of this study was to investigate the risk for asthma in relation to exposure to styrene in a large number of workers. A total of 47 workers with a history of exposure to styrene were included in the study. To establish whether asthma was present, each patient underwent a clinical interview, pulmonary function testing and bronchial challenge with methacholine. Specific bronchial challenges with styrene and serial peak expiratory flow (PEF) measurement at home and at work were carried out in subjects with a diagnosis of asthma to evaluate the relationship between their asthma and exposure to styrene in the workplace. Among the 47 subjects, 5 workers had given a history of work-related symptoms, and 3 of them had a positive methacholine challenge test. Specific bronchial challenges with styrene and serial PEF measurement were subsequently carried out in these 3 subjects. Although provocation tests with styrene were negative in the 3 workers, 1 worker had PEF rate records compatible with occupational asthma. We established one patient with occupational asthma from a group of people who have excessive styrene exposure. This finding may be suggestive but is not conclusive about the causative role of styrene in occupational asthma. Since styrene is a frequently used substance in the furniture industry, it is worth performing further studies to investigate the relationship between styrene and occupational asthma. Copyright 2004 S. Karger AG, Basel
Guelfi, Diego Roberto Vieira; Gozzi, Fábio; Sirés, Ignasi; Brillas, Enric; Machulek, Amílcar; de Oliveira, Silvio César
2017-03-01
A solution with 0.38 mM of the pesticide propoxur (PX) at pH 3.0 has been comparatively treated by electrochemical oxidation with electrogenerated H 2 O 2 (EO-H 2 O 2 ), electro-Fenton (EF), and photoelectro-Fenton (PEF). The trials were carried out with a 100-mL boron-doped diamond (BDD)/air-diffusion cell. The EO-H 2 O 2 process had the lowest oxidation ability due to the slow reaction of intermediates with • OH produced from water discharge at the BDD anode. The EF treatment yielded quicker mineralization due to the additional • OH formed between added Fe 2+ and electrogenerated H 2 O 2 . The PEF process was the most powerful since it led to total mineralization by the combined oxidative action of hydroxyl radicals and UVA irradiation. The PX decay agreed with a pseudo-first-order kinetics in EO-H 2 O 2 , whereas in EF and PEF, it obeyed a much faster pseudo-first-order kinetics followed by a much slower one, which are related to the oxidation of its Fe(II) and Fe(III) complexes, respectively. EO-H 2 O 2 showed similar oxidation ability within the pH range 3.0-9.0. The effect of current density and Fe 2+ and substrate contents on the performance of the EF process was examined. Two primary aromatic products were identified by LC-MS during PX degradation.
Watanabe, Masanari; Kurai, Jun; Sano, Hiroyuki; Saito, Rumiko; Kimura, Yutaka; Aiba, Setsuya; Oshimura, Mitsuo; Yamasaki, Akira; Shimizu, Eiji
2015-01-01
The objective of the study was to investigate the influence of Asian dust storms (ADS) on pulmonary function of school children and the relationship of this effect with interleukin-8. Morning peak expiratory flow (PEF) was measured daily in 399 children from April to May 2012 and in 384 of these children from March to May 2013. The data were analyzed for an association between ADS events and PEF by linear mixed models. Interleukin-8 transcriptional activity was assessed in THP-G8 cells stimulated by airborne particles collected on ADS days. Seven ADS days were identified: April 23 and 24, 2012; March 8 to 10, 2013; and March 19 and 20, 2013. Changes in PEF after ADS exposure were −8.17 L/min (95% confidence interval, −11.40 to −4.93) in 2012 and −1.17 L/min (−4.07 to 1.74) in 2013, and there was a significant difference between 2012 and 2013. Interleukin-8 transcriptional activity was significantly higher in 2012 at 10.6 ± 2.9-fold compared to 3.7 ± 0.4 in March 8 to 10, 2013, and 2.3 ± 0.2 in March 19 and 20, 2013. The influence of ADS events on pulmonary function of children differs with each ADS event and may be related to interleukin-8 production. PMID:26060816
Watanabe, Masanari; Noma, Hisashi; Kurai, Jun; Sano, Hiroyuki; Kitano, Hiroya; Saito, Rumiko; Kimura, Yutaka; Aiba, Setsuya; Oshimura, Mitsuo; Shimizu, Eiji
2015-01-01
This study aimed to investigate the effects of particulate matter (PM) on pulmonary function in schoolchildren, as well as the relationships of these effects with interleukin-8. Morning peak expiratory flow (PEF) was measured daily in 399 children during April–May 2012, and in 384 of these children during March–May 2013. PEF’s association with the daily levels of suspended particulate matter (SPM) and PM < 2.5 μm (PM2.5) was estimated using a linear mixed model. Interleukin-8 promoter activity was assessed in THP-G8 cells stimulated by fallen PM collected at Tottori University Hospital during four periods (two in 2012 and two in 2013). An increase of 14.0 μg/m3 in SPM led to PEF changes of −2.16 L/min in 2012 and −0.81 L/min in 2013, respectively. An increment of 10.7 μg/m3 in PM2.5 was associated with PEF changes of −2.58 L/min in 2012 and −0.55 L/min in 2013, respectively. These associations were only significant in 2012. Interleukin-8 promoter activity was significantly higher in both periods of 2012 than in 2013. There was a significant association between pulmonary function in schoolchildren and daily levels of SPM and PM2.5, but this association may differ depending on the PM’s ability to elicit interleukin-8 production. PMID:26569272
Kasote, D. M.; Badhe, Y. S.; Zanwar, A. A.; Hegde, M. V.; Deshmukh, K. K.
2012-01-01
Objective: to investigate the hepatoprotective potential of ether insoluble phenolic components of n-butanol fraction (EPC-BF) of flaxseed against CCl4 -induced liver damage in rats. Materials and Methods: Hepatotoxicity was induced to Wistar rats by administration of 0.2% CCl4 in olive oil (8 mL/kg, i.p.) on the seventh day of treatment. Hepatoprotective potential of EPC-BF at doses, 250 and 500 mg/kg, p.o. was assessed through biochemical and histological parameters. Results: EPC-BF and silymarin pretreated animal groups showed significantly decreased activities of Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and level of total bilirubin, elevated by CCl4 intoxication. Hepatic lipid peroxidation elevated by CCl4 intoxication were also found to be alleviated at almost normal level in the EPC-BF and silymarin pretreated groups. Histological studies supported the biochemical findings and treatment of EPC-BF at doses 250 and 500 mg/kg, p.o. was found to be effective in restoring CCl4 -induced hepatic damage. However, EPC-BF did not show dose-dependent hepatoprotective potential. EPC-BF depicted maximum protection against CCl4 -induced hepatic damage at lower dose 250 mg/kg than higher dose (500 mg/ kg). Conclusion: EPC-BF possesses the significant hepatoprotective activity against CCl4 induced liver damage, which could be mediated through increase in antioxidant defenses. PMID:22923966
Hu, Ting; He, Xiao-Wei; Jiang, Jian-Guo
2014-08-27
Ilex latifolia Thunb., widely distributed in China, has been used as a functional food and drunk for a long time. This study was aimed to identify the bioactive constituents with antioxidant, antitumor, and anti-inflammatory properties. I. latifolia was extracted with 95% ethanol and then partitioned into four fractions: petroleum ether fraction, ethyl acetate fraction, n-butanol fraction, and water fraction. Results showed that the ethyl acetate fraction was found to have significant ferric reducing antioxidant power activity, DPPH radical scavenging activity, and oxygen radical absorbance capacity, cytotoxicity against human cervix carcinoma HeLa cells, and inhibitory effect on NO production in macrophage RAW 264.7 cells. Five compounds were isolated from the ethyl acetate fraction, and they were identified as ethyl caffeate (1), ursolic acid (2), chlorogenic acid (3), 3,4-di-O-caffeoylquinic acid methyl ester (4), and 3,5-di-O-caffeoylquinic acid methyl ester (5), the last two of which were isolated for the first time from I. latifolia. Compounds 4 and 5 exhibited cytotoxicity actions against tumor cell line. Compound 3 showed the strongest anti-inflammatory activity of all the compounds. The results obtained in this work might contribute to the understanding of biological activities of I. latifolia and further investigation on its potential application values for food and drug.
Khan, Alam; Islam, Md Hedayetul; Islam, Md Ekramul; Al-Bari, Md Abdul Alim; Parvin, Mst Shahnaj; Sayeed, Mohammed Abu; Islam, Md Nurul; Haque, Md Ekramul
2014-10-01
Tribolium castaneum (Herbst) is a harmful pest of stored grain and flour-based products in tropical and subtropical region. In the present study, rhizome of Drynaria quercifolia (J. Smith) was evaluated for pesticidal and pest repellency activities against T. castaneum, using surface film method and filter paper disc method, respectively. In addition, activity of the isolated compound 3,4-dihydroxybenzoic acid was evaluated against the pest. Chloroform soluble fraction of ethanol extract of rhizome of D. quercifolia showed significant pesticidal activity at doses 0.88 to 1.77 mg/cm(2) and significant pest repellency activity at doses 0.94 to 0.23 mg/cm(2). No pesticidal and pest repellency activity was found for petroleum ether, ethyl acetate and methanol soluble fractions of ethanol extract as well as for 3,4-dihydroxybenzoic acid. Considering our findings it can be concluded that chloroform soluble fraction of rhizome of D. quercifolia is useful in controlling T. castaneum of stored grain and flour-based products.
Kamran, Muhammad; Khan, Abdul L; Ali, Liaqat; Hussain, Javid; Waqas, Muhammad; Al-Harrasi, Ahmed; Imran, Qari M; Kim, Yoon-Ha; Kang, Sang-Mo; Yun, Byung-Wook; Lee, In-Jung
2017-01-01
Plant-derived smoke has been known to play an important role in distribution and growth of vegetation. Using a proficiently designed furnace, we extracted smoke from the leaves of four plant viz. Helianthus annuus , Aloe vera , Ginkgo biloba , and Cymbopogon jwarancusa . Smoke dilutions obtained from these plants were obtained in different concentrations to identify potential lettuce growth promoting smoke solution. Results revealed that smoke obtained from G. biloba significantly enhanced the lettuce seed germination. This solution was then partitioned into ethyl acetate, dichloromethane, n -hexane, chloroform and ether fractions. Ethyl acetate fraction was found to be potent to enhance seed germination. This fraction was subjected to column chromatography and spectroscopic techniques to obtain compound 1 . This compound was identified as hydroquinone using 1D and 2D NMR techniques. At low concentrations (5, 10, and 20 ppm), compound 1 enhanced the lettuce seed germination; however, higher concentrations inhibited its growth as compared to control.
New phenolic grape skin products from Vitis vinifera cv. Pinot Noir.
Kneknopoulos, Petros; Skouroumounis, George K; Hayasaka, Yoji; Taylor, Dennis K
2011-02-09
Anthocyanins and their related compounds were extracted from grape skins of Pinot noir, using 50% aqueous methanol, and purified by solid phase extraction chromatography using XAD-7 resin to obtain a pigment-rich fraction. This fraction was subjected to multilayer coil countercurrent chromatography (MLCCC) using a quaternary solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water acidified with 0.01% trifluoroacetic acid (2:2:0.1-1.8:5) (v/v/v/v) in a step gradient elution to separate anthocyanin oligomers from grape anthocyanins. In the process of the characterization of the MLCCC fractions by electrospray mass spectrometry, two noncolored anthocyanin derivatives were found and characterized on the basis of their mass spectral data. As a result, these compounds have been tentatively identified as coupling products between both hydrated malvidin-3-glucoside and peonidin-3-glucoside, with 2-S-glutathionyl caffeoyl tartaric acid (GRP). It is therefore proposed that grape skins contain this new class of coupling product, and a possible chemical pathway for their formation is suggested.
NASA Astrophysics Data System (ADS)
Kamran, Muhammad; Khan, Abdul L.; Ali, Liaqat; Hussain, Javid; Waqas, Muhammad; Al-Harrasi, Ahmed; Imran, Qari M.; Kim, Yoon-Ha; Kang, Sang-Mo; Yun, Byung-Wook; Lee, In-Jung
2017-05-01
Plant-derived smoke has been known to play an important role in distribution and growth of vegetation. Using a proficiently designed furnace, we extracted smoke from the leaves of four plant viz. Helianthus annuus, Aloe vera, Ginkgo biloba, and Cymbopogon jwarancusa. Smoke dilutions obtained from these plants were obtained in different concentrations to identify potential lettuce growth promoting smoke solution. Results revealed that smoke obtained from Ginkgo biloba significantly enhanced the lettuce seed germination. This solution was then partitioned into ethyl acetate, dichloromethane, n-hexane, chloroform and ether fractions. Ethyl acetate fraction was found to be potent to enhance seed germination. This fraction was subjected to column chromatography and spectroscopic techniques to obtain compound 1. This compound was identified as hydroquinone using 1D and 2D NMR techniques. At low concentrations (5, 10 and 20 ppm), compound 1 enhanced the lettuce seed germination; however, higher concentrations inhibited its growth as compared to control.
Kamran, Muhammad; Khan, Abdul L.; Ali, Liaqat; Hussain, Javid; Waqas, Muhammad; Al-Harrasi, Ahmed; Imran, Qari M.; Kim, Yoon-Ha; Kang, Sang-Mo; Yun, Byung-Wook; Lee, In-Jung
2017-01-01
Plant-derived smoke has been known to play an important role in distribution and growth of vegetation. Using a proficiently designed furnace, we extracted smoke from the leaves of four plant viz. Helianthus annuus,Aloe vera,Ginkgo biloba, and Cymbopogon jwarancusa. Smoke dilutions obtained from these plants were obtained in different concentrations to identify potential lettuce growth promoting smoke solution. Results revealed that smoke obtained from G. biloba significantly enhanced the lettuce seed germination. This solution was then partitioned into ethyl acetate, dichloromethane, n-hexane, chloroform and ether fractions. Ethyl acetate fraction was found to be potent to enhance seed germination. This fraction was subjected to column chromatography and spectroscopic techniques to obtain compound 1. This compound was identified as hydroquinone using 1D and 2D NMR techniques. At low concentrations (5, 10, and 20 ppm), compound 1 enhanced the lettuce seed germination; however, higher concentrations inhibited its growth as compared to control. PMID:28553632
Ethnopharmacological investigation of the aerial part of Phragmites karka (Poaceae).
Sultan, Ramiz Ahmed; Kabir, Mohammad Shah Hafez; Uddin, Mir Muhammad Nasir; Uddin, Mohi; Mahmud, Zobaer Al; Raihan, Sheikh Zahir; Qais, Nazmul
2017-05-01
In this ethnopharmacological study, methanolic extract of the aerial plant parts of Phragmites karka (Family: Poaceae) and its petroleum ether and carbon tetrachloride fractions were investigated for bioactivities in Swiss-albino mice, namely, analgesic, central nervous system (CNS) depressant, hypoglycemic, and antidiarrheal activity. The cold methanolic extract of the aerial plant parts of Phragmites karka (MEPK) was first prepared, and it was then further fractionated as petroleum ether (PEFMEPK) and carbon tetrachloride (CTFMEPK) fractions. Analgesic activity was performed employing acidic acid-induced writhing test, central analgesic effect by radiant heat tail-flick method. CNS depressant activity was evaluated by phenobarbitone-induced sleeping time test. Hypoglycemic activity was tested by glucose tolerance test (GTT). Antidiarrheal activity was evaluated by castor oil-induced diarrhea method. For all in vivo tests, doses of 200 and 400 mg/kg body weight were used. In the mice model, the MEPK, PEFMEPK, and CTFMEPK fractions showed significant peripheral analgesic activity at a dose of 400 mg/kg body weight with percentage of inhibition of acetic acid-induced writhing 77.67 (p<0.001), 33.50 (p<0.001), and 40.29 (p<0.001), respectively, compared to the standard dichlofenac (60.68%, p<0.001) group. The hypoglycemic properties of MEPK, PEFMEPK, and CTFMEPK extracts were evaluated in normoglycemic mice where the reduction of blood glucose level after 30 min of glucose load were 69.85%, 78.91%, and 72.73%, respectively, and for standard glibenclamide, the reduction was 72.85%. All results were significant (p<0.05). In the case of the CNS depressant activity by phenobarbitone-induced sleeping time test, the crude ME significantly reduced sleep latency by 57.14% and increased the duration of sleep by 63.29% compared to the control, which were comparable to that of standard diazepam (65.71% and 77.62%, respectively). Among all the extract and fractions, methanolic extract showed the maximum antidiarrheal effect. The methanolic extract at 200 mg/kg dose induced a significant decrease in the total number of defecation in 4 h (69.05% of inhibition, p<0.001) and at 400 mg/kg dose showed 76.19% of inhibition (p<0.001). In light of the available literature, these findings represent the first experimental investigation of biological activities of P. karka in the perspective of their traditional use.
Nonlinear microscopy of collagen fibers
NASA Astrophysics Data System (ADS)
Strupler, M.; Pena, A.-M.; Hernest, M.; Tharaux, P.-L.; Fabre, A.; Marchal-Somme, J.; Crestani, B.; Débarre, D.; Martin, J.-L.; Beaurepaire, E.; Schanne-Klein, M.-C.
2007-02-01
We used intrinsic Second Harmonic Generation (SHG) by fibrillar collagen to visualize the three-dimensional architecture of collagen fibrosis at the micrometer scale using laser scanning nonlinear microscopy. We showed that SHG signals are highly specific to fibrillar collagen and provide a sensitive probe of the micrometer-scale structural organization of collagen in tissues. Moreover, recording simultaneously other nonlinear optical signals in a multimodal setup, we visualized the tissue morphology using Two-Photon Excited Fluorescence (2PEF) signals from endogenous chromophores such as NADH or elastin. We then compared different methods to determine accurate indexes of collagen fibrosis using nonlinear microscopy, given that most collagen fibrils are smaller than the microscope resolution and that second harmonic generation is a coherent process. In order to define a robust method to process our three-dimensional images, we either calculated the fraction of the images occupied by a significant SHG signal, or averaged SHG signal intensities. We showed that these scores provide an estimation of the extension of renal and pulmonary fibrosis in murine models, and that they clearly sort out the fibrotic mice.
Models of metal binding structures in fulvic acid from the Suwannee River, Georgia
Leenheer, J.A.; Brown, G.K.; MacCarthy, P.; Cabaniss, S.E.
1998-01-01
Fulvic acid, isolated from the Suwannee River, Georgia, was assessed for its ability to bind Ca2+, Cd2+, Cu2+, Ni2+, and Zn2+ ions at pH 6 before and after extensive fractionation that was designed to reveal the nature of metal binding functional groups. The binding constant for Ca2+ ion had the greatest increase of all the ions in a metal binding fraction that was selected for intensive characterization for the purpose of building quantitative average model structures. The 'metal binding' fraction was characterized by quantitative 13C NMR, 1H NMR, and FT-1R spectrometry and elemental, titrimetric, and molecular weight determinations. The characterization data revealed that carboxyl groups were clustered in short- chain aliphatic dibasic acid structures. The Ca2+ binding data suggested that ether-substituted oxysuccinic acid structures are good models for the metal binding sites at pH 6. Structural models were derived based upon oxidation and photolytic rearrangements of cutin, lignin, and tannin precursors. These structural models rich in substituted dibasic acid structures revealed polydentate binding sites with the potential for both inner-sphere and outer-sphere type binding. The majority of the fulvic acid molecule was involved with metal binding rather than a small substructural unit.Fulvic acid, isolated from the Suwannee River, Georgia, was assessed for its ability to bind Ca2+, Cd2+, Cu2+, Ni2+, and Zn2+ ions at pH 6 before and after extensive fractionation that was designed to reveal the nature of metal binding functional groups. The binding constant for Ca2+ ion had the greatest increase of all the ions in a metal binding fraction that was selected for intensive characterization for the purpose of building quantitative average model structures. The `metal binding' fraction was characterized by quantitative 13C NMR, 1H NMR, and FT-IR spectrometry and elemental, titrimetric, and molecular weight determinations. The characterization data revealed that carboxyl groups were clustered in short-chain aliphatic dibasic acid structures. The Ca2+ binding data suggested that ether-substituted oxysuccinic acid structures are good models for the metal binding sites at pH 6. Structural models were derived based upon oxidation and photolytic rearrangements of cutin, lignin, and tannin precursors. These structural models rich in substituted dibasic acid structures revealed polydentate binding sites with the potential for both inner-sphere and outer-sphere type binding. The majority of the fulvic acid molecule was involved with metal binding rather than a small substructural unit.
New Polyacetylenes, DGAT inhibitors from the roots of Panax ginseng.
Lee, Seung Woong; Kim, Koanhoi; Rho, Mun-Chual; Chung, Mi Yeon; Kim, Young Ho; Lee, Sangku; Lee, Hyun Sun; Kim, Young Kook
2004-03-01
The petroleum ether extract of Panax ginseng showed a significant inhibition of the diacylglycerol acyltransferase (DGAT) enzyme from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of two new polyacetylenic compounds, (9 R,10 S)-epoxyheptadecan-4,6-diyn-3-one ( 1) and 1-methoxy-(9 R,10 S)-epoxyheptadecan-4,6-diyn-3-one ( 2). Their chemical structures were elucidated on the basis of spectroscopic evidence and asymmetric synthesis. IC50 values of 9 microg/mL ( 1) and 32 microg/mL ( 2) were obtained.
Physical and chemical properties of the transmissible mink encephalopathy agent.
Marsh, R F; Hanson, R P
1969-02-01
The size of the transmissible mink encephalopathy (TME) agent is estimated to be less than 50 nm on the basis of its passage through membrane filters. The agent is sensitive to ether, relatively resistant to 10% Formalin, resistant to ultraviolet irradiation, and susceptible to proteolytic digestion with Pronase. Attempts to extract an infectious nucleic acid fraction with hot phenol were unsuccessful. The results of these studies indicate that the TME agent has biochemical properties which are similar to those described for the transmissible agent of scrapie.
Simulation studies for surfaces and materials strength
NASA Technical Reports Server (NTRS)
Halicioglu, T.
1985-01-01
From intermolecular force studies, it is now known that the overall non-additive contribution to the lattice enegy is positive so that analysis based on only pairwise additivity suggests a shallower intermolecular potential than the true value. Two body contributions alone are also known to be categorically unable to even qualitatively describe some configurations of molecular clusters in the gas phase or the general relaxation and reconstruction of fcc crystal surfaces. In addition, the many-body contribution was shown to play a key role in the stability of certain crystal structures. In these recent analyses, a relatively simple potential energy function (PEF), comprising only a two-body Mie-type potential plus a three-body Axilrod-Teller-type potential, was found to be extremely effective. This same parametric PEF is applied to describe the bulk stability and surface energy for the diamond cubic structure. To test the stability condition, the FCC, BCC, diamond cubic, graphite and beta-tin structures were considered.
Respiratory effects among rubberwood furniture factory workers in Thailand.
Sriproed, Salakjit; Osiri, Pramuk; Sujirarat, Dusit; Chantanakul, Suttinun; Harncharoen, Kitiphong; Ong-artborirak, Parichat; Woskie, Susan R
2013-01-01
Respiratory symptoms and pulmonary function were examined among 89 rubberwood furniture factory workers. Acute and chronic irritant symptoms were assessed, lung function was measured both pre- and post-shift and personal inhalable dust exposure determined. The only symptoms with a significant increase among high dust level-exposed workers (>1 mg/m(3)) were those related to nasal irritation. High dust level-exposed workers had a significant cross-shift decrease in forced expiratory volume in 1 second/forced vital capacity (FEV(1)/FVC) compared with low dust level-exposed workers and increases in inhalable dust concentration levels (mg/m(3)) were significantly associated with decreases in the peak expiratory flow (PEF) across the work shift. For percent predicted pulmonary function levels, a significant decrement in PEF was found for high versus low rubberwood dust level-exposed workers, after controlling for confounders. These findings suggest the need for an occupational standard for rubberwood dust in Thailand.
Optimizing ultrafast illumination for multiphoton-excited fluorescence imaging
Stoltzfus, Caleb R.; Rebane, Aleksander
2016-01-01
We study the optimal conditions for high throughput two-photon excited fluorescence (2PEF) and three-photon excited fluorescence (3PEF) imaging using femtosecond lasers. We derive relations that allow maximization of the rate of imaging depending on the average power, pulse repetition rate, and noise characteristics of the laser, as well as on the size and structure of the sample. We perform our analysis using ~100 MHz, ~1 MHz and 1 kHz pulse rates and using both a tightly-focused illumination beam with diffraction-limited image resolution, as well loosely focused illumination with a relatively low image resolution, where the latter utilizes separate illumination and fluorescence detection beam paths. Our theoretical estimates agree with the experiments, which makes our approach especially useful for optimizing high throughput imaging of large samples with a field-of-view up to 10x10 cm2. PMID:27231620
[Lung dysfunction in patients with severe chronic obstructive bronchitis].
Nefedov, V B; Popova, L A; Shergina, E A
2005-01-01
VC, FVC, FEV1, FEV1/VC%, PEF, MEF25, MEF50, MEF75, TCL, TGV, RV, Raw, Rin, Rex, DLCO-SS, PaO2, and PaCO2 were determined in 36 patients with severe chronic obstructive lung disease (FEV1 < 50% of the normal value). All the patients were found to have impaired bronchial patency and changes in lung volumes and capacities; 83.3% of the patients had pulmonary gas exchange dysfunction. Impaired bronchial patency mainly appeared as decreased FEV1, FEV1/VC%, PEF, MEF25, MEF50, MEF75, Raw, Rin, Rex; altered lung volumes and capacities manifested by increased RV, TGV, and TLC, and by decreased VC and FVC; pulmonary gas exchange dysfunction showed up as lowered PaO2 and DLCO-SS, as decreased or increased PaCO2. The observed bronchial patency disorders varied from significant to severe; functional changes in lung volumes and capacities were mild to severe.
Poly(arylene ether)s containing pendent ethynyl groups
NASA Technical Reports Server (NTRS)
Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)
1996-01-01
Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350.degree. C. to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.
Poly(arylene ether)s containing pendent ethynyl groups
NASA Technical Reports Server (NTRS)
Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)
1994-01-01
Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350 C to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.
The identity of Romanian amber (rumanite) with Baltic amber (succinite).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stout, E. C.; Beck, C. W.; Anderson, K. B.
Romanian amber (rumanite) has been considered to be a separate species of fossil resin for more than a century. While earlier investigators held it to be very similar to succinite (Baltic amber), modern scholars have assigned it a distinctly different botanical origin. We have found that almost all of the constituents of the ether-soluble fractions of 13 specimens of authentic rumanite identified by gas chromatography-mass spectrometry have previously been reported in the soluble fraction of succinite, including succinic acid and its monoterpene esters. Additionally and significantly, the soluble fraction of rumanite contains a number defunctionalized compounds that do not preexistmore » in succinite, but that are produced by pyrolysis of whole succinite or of its insoluble polymeric fraction. Simultaneous methylation pyrolysis-gas chromatography-mass spectrometry of the polymeric fraction of seven of the rumanite specimens yielded further copious amounts of dimethyl succinate, a number of diterpene resin acid methyl esters, and additional defunctionalized compounds known to be pyrolysis products of succinite. The evidence shows conclusively that the botanical origin of rumanite is not distinct from that of succinite. Rather, rumanite is a succinite that has suffered partial thermal degradation in the course of the folding of the Oligocene Kliwa sandstone formation in which it is most commonly found.« less
Cao, Xiaoyan; Drosos, Marios; Leenheer, Jerry A; Mao, Jingdong
2016-02-16
A lignite humic acid (HA) was separated from inorganic and non-HA impurities (i.e., aluminosilicates, metals) and fractionated by a combination of dialysis and XAD-8 resin. Fractionation revealed a more homogeneous structure of lignite HA. New and more specific structural information on the main lignite HA fraction is obtained by solid-state nuclear magnetic resonance (NMR) spectroscopy. Quantitative (13)C multiple cross-polarization (multiCP) NMR indicated oxidized phenyl propane structures derived from lignin. MultiCP experiments, conducted on potassium HA salts titrated to pH 10 and pH 12, revealed shifts consistent with carboxylate and phenolate formation, but structural changes associated with enolate formation from aromatic beta keto acids were not detected. Two-dimensional (1)H-(13)C heteronuclear correlation (2D HETCOR) NMR indicated aryl-aliphatic ketones, aliphatic and aromatic carboxyl groups, phenol, and methoxy phenyl ethers. Acidic protons from carboxyl groups in both the lignite HA fraction and a synthetic HA-like polycondensate were found to be hydrogen-bonded with electron-rich aromatic rings. Our results coupled with published infrared spectra provide evidence for the preferential hydrogen bonding of acidic hydrogens with electron-rich aromatic rings rather than adjacent carbonyl groups. These hydrogen-bonding interactions likely result from stereochemical arrangements in primary structures and folding.
Ramjan, Ali; Hossain, Marjan; Runa, Jannatul Ferdous; Md, Hasanuzzaman; Mahmodul, Islam
2014-01-01
Objective: The present study is aimed to investigate in vitro thrombolytic activity of three Bangladeshi medicinal plants Averrhoa bilimbi (Oxalidiaceae), Clerodendrum viscosum (Verbanaceae) and Drynaria quercifolia (Polypodiaceae). Materials and methods: Each the plant was extracted with methanol at room temperature and the concentrated methanolic extracts (MEF) were fractionated by the modified Kupchan partitioning method to render pet-ether soluble fraction (PESF), carbon tetrachloride soluble fraction (CTSF), chloroform soluble fraction (CSF) and aqueous soluble fraction (AQSF). To observe their thrombolytic potential, a prompt and swift method was involved where streptokinase and water were used as positive and negative control, respectively. Result: Among the three plants, AQSF and PESF of D. quercifolia with CTSF of C. viscosum exhibited highest thrombolytic activity by clot lysis of 34.38%, 34.27% and 28.64%, respectively. Among other extracts A. bilimbi, C. viscosun and D.quercifolia showed significant percentage (%) of clot lysis compared to standard streptokinase (41.05%) while the negative control water revealed 3.31 % lysis of clot. Conclusion: From our findings it is observed that all the plants revealed remarkable thrombolytic activity. Therefore, steps should be taken to observe in vivo clot dissolving potential and to isolate active component(s) of these extracts. PMID:25386407
Bone Marrow Lipids in Rats Exposed to Total-Body Irradiation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Snyder, Fred; Cress, Edgar A.
1963-05-01
ABS>Thin-layer chromatography was used to demonstrate that bone marrow lipids of rats were primarily triglycerides; gas-liquid chromatography of the fraction revealed that palmitic and oleic acids account for more than 80% of the fatty acids. Minor lipid components present in the control and irradiated marrow are glyceryl ethers, cholesterol, fatty acids, and phospholipids. Cholesterol esters were not found. Total-body irradiation (800 r) increases the femur marrow triglyceride fraction approximately six times by 1 week after irradiation, and it remains elevated for many weeks. The relationship between dose and increase in marrow triglycerides appears to fit the equation y = bxmore » a. The water and lipid content of bone marrow bear a reciprocal relation to each other, while both water and residue are significantly reduced in the irradiated femur marrow.« less
Abu-Gharbieh, Eman; Shehab, Naglaa Gamil
2017-04-18
Hyperglycemia is a complicated condition accompanied with high incidence of infection and dyslipidemia. This study aimed to explore the phyto-constituents of Crataegus azarolus var. eu- azarolus Maire leaves, and to evaluate the therapeutic potentials particularly antimicrobial, antihyperglycemic and antihyperlipidemic of the extract and the isolated compound (3β-O-acetyl ursolic acid). Total phenolics and flavonoidal contents were measured by RP-HPLC analysis. Free radicals scavenging activity of different extraction solvents was tested in-vitro on DPPH free radicals. The antimicrobial activity of the ethanolic extract and its fractions as well as the isolated compounds were evaluated in-vitro on variable microorganisms. Animal models were used to evaluate the antihyperglycemic and antihyperlipidemic activities of the ethanolic extract along with the isolated compound (3β-O acetyl ursolic acid). RP- HPLC analysis of the phenolics revealed high content of rutin, salicylic and ellagic acids. Six compounds belonging to triterpenes and phenolics were isolated from chloroform and n-butanol fractions namely: ursolic acid, 3β-O-acetyl ursolic acid, ellagic acid, quercetin 3-O-β methyl ether, rutin and apigenin7-O-rutinoside. Ethanolic extract showed the highest DPPH radical scavenger activity compared to other solvents. Ethanolic extract, hexane fraction, ursolic acid, 3β-O acetyl ursolic acid and quercetin 3-O-methyl ether showed variable antimicrobial activity against E. coli, P. aeruginosa, S. aureus, and C. albicans. Administration of the ethanolic extract or 3β-O acetyl ursolic acid orally to the mice reduced blood glucose significantly in a time- and dose-dependent manner. Ethanolic extract significantly reduced LDL-C, VLDL-C, TC and TG and increased HDL-C in rats. Ethanolic extract and 3β-O acetyl ursolic acid reduced in-vitro activity of pancreatic lipase. This study reveals that Crataegus azarolus var. eu- azarolus Maire has the efficiency to control hyperglycemia with its associated complications. This study is the first to evaluate antihyperglycemic and antihyperlipidemic potentials of 3β-O acetyl ursolic acid.
Radiolabeled cholesteryl ethers: A need to analyze for biological stability before use.
Manual Kollareth, Denny Joseph; Chang, Chuchun L; Hansen, Inge H; Deckelbaum, Richard J
2018-03-01
Radiolabeled cholesteryl ethers are widely used as non-metabolizable tracers for lipoproteins and lipid emulsions in a variety of in vitro and in vivo experiments. Since cholesteryl ethers do not leave cells after uptake and are not hydrolyzed by mammalian cellular enzymes, these compounds can act as markers for cumulative cell uptakes of labeled particles. We have employed [ 3 H]cholesteryl oleoyl ether to study the uptake and distribution of triglyceride-rich emulsion particles on animal models. However, questionable unexpected results compelled us to analyze the stability of these ethers. We tested the stability of two commercially available radiolabeled cholesteryl ethers - [ 3 H]cholesteryl oleoyl ether and [ 3 H]cholesteryl hexadecyl ether from different suppliers, employing in vitro , in vivo and chemical model systems. Our results show that, among the two cholesteryl ethers tested, one ether was hydrolyzed to free cholesterol in vitro , in vivo and chemically under alkaline hydrolyzing agent. Free cholesterol, unlike cholesteryl ether, can then re-enter the circulation leading to confounding results. The other ether was not hydrolyzed to free cholesterol and remained as a stable ether. Hence, radiolabeled cholesteryl ethers should be analyzed for biological stability before utilizing them for in vitro or in vivo experiments.
Method to produce American Thoracic Society flow-time waveforms using a mechanical pump.
Hankinson, J L; Reynolds, J S; Das, M K; Viola, J O
1997-03-01
The American Thoracic Society (ATS) recently adopted a new set of 26 standard flow-time waveforms for use in testing both diagnostic and monitoring devices. Some of these waveforms have a higher frequency content than present in the ATS-24 standard volume-time waveforms, which, when produced by a mechanical pump, may result in a pump flow output that is less than the desired flow due to gas compression losses within the pump. To investigate the effects of gas compression, a mechanical pump was used to generate the necessary flows to test mini-Wright and Assess peak expiratory flow (PEF) meters. Flow output from the pump was measured by two different independent methods, a pneumotachometer and a method based on piston displacement and pressure measured within the pump. Measuring output flow based on piston displacement and pressure has been validated using a pneumotachometer and mini-Wright PEF meter, and found to accurately measure pump output. This method introduces less resistance (lower back-pressure) and dead space volume than using a pneumotachometer in series with the meter under test. Pump output flow was found to be lower than the desired flow both with the mini-Wright and Assess meters (for waveform No. 26, PEFs 7.1 and 10.9% lower, respectively). To compensate for losses due to gas compression, we have developed a method of deriving new input waveforms, which, when used to drive a commercially available mechanical pump, accurately and reliably produces the 26 ATS flow-time waveforms, even those with the fastest rise-times.
Leidy, Nancy K; Kim, Katherine; Bacci, Elizabeth D; Yawn, Barbara P; Mannino, David M; Thomashow, Byron M; Barr, R Graham; Rennard, Stephen I; Houfek, Julia F; Han, Meilan K; Meldrum, Catherine A; Make, Barry J; Bowler, Russ P; Steenrod, Anna W; Murray, Lindsey T; Walsh, John W; Martinez, Fernando
2015-01-01
Background: Many cases of chronic obstructive pulmonary disease (COPD) are diagnosed only after significant loss of lung function or during exacerbations. Aims: This study is part of a multi-method approach to develop a new screening instrument for identifying undiagnosed, clinically significant COPD in primary care. Methods: Subjects with varied histories of COPD diagnosis, risk factors and history of exacerbations were recruited through five US clinics (four pulmonary, one primary care). Phase I: Eight focus groups and six telephone interviews were conducted to elicit descriptions of risk factors for COPD, recent or historical acute respiratory events, and symptoms to inform the development of candidate items for the new questionnaire. Phase II: A new cohort of subjects participated in cognitive interviews to assess and modify candidate items. Two peak expiratory flow (PEF) devices (electronic, manual) were assessed for use in screening. Results: Of 77 subjects, 50 participated in Phase I and 27 in Phase II. Six themes informed item development: exposure (smoking, second-hand smoke); health history (family history of lung problems, recurrent chest infections); recent history of respiratory events (clinic visits, hospitalisations); symptoms (respiratory, non-respiratory); impact (activity limitations); and attribution (age, obesity). PEF devices were rated easy to use; electronic values were significantly higher than manual (P<0.0001). Revisions were made to the draft items on the basis of cognitive interviews. Conclusions: Forty-eight candidate items are ready for quantitative testing to select the best, smallest set of questions that, together with PEF, can efficiently identify patients in need of diagnostic evaluation for clinically significant COPD. PMID:26028486
Israel, E; Drazen, J M; Liggett, S B; Boushey, H A; Cherniack, R M; Chinchilli, V M; Cooper, D M; Fahy, J V; Fish, J E; Ford, J G; Kraft, M; Kunselman, S; Lazarus, S C; Lemanske, R F; Martin, R J; McLean, D E; Peters, S P; Silverman, E K; Sorkness, C A; Szefler, S J; Weiss, S T; Yandava, C N
2001-01-01
Regular use of inhaled beta-adrenergic agonists may have adverse effects in some asthma patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect its regulation; however, results of smaller studies of the effects of such polymorphisms on response to beta-agonist therapy have been inconsistent. We examined the possible effects of polymorphisms at codons 16 (beta(2)-AR-16) and 27 (beta(2)-AR-27) on response to albuterol by genotyping 190 asthmatics who had participated in a trial of regular versus as-needed albuterol use. During the 16-week treatment period, patients homozygous for arginine (Arg/Arg) at beta(2)-AR-16 who used albuterol regularly had a small decline in morning peak expiratory flow (AM PEF). This effect was magnified during a 4-week run-out period, when all patients returned to as-needed albuterol only. By the end of the study, Arg/Arg subjects who had used albuterol regularly had an AM PEF 30.5 +/- 12.1 liters/min lower (p = 0.012) than Arg/Arg patients who had used albuterol as needed only. Subjects homozygous for glycine at beta(2)-AR-16 showed no such decline. Evening PEF also declined in the Arg/Arg regular but not in as-need albuterol users. No significant differences between regular and as-needed treatment were associated with polymorphisms at beta(2)-AR-27. Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment. Copyright 2001 S. Karger AG, Basel
Effect of physical effectiveness on digestibility of ration for cows in early lactation.
Stojanovic, B; Grubic, G; Djordjevic, N; Bozickovic, A; Ivetic, A; Davidovic, V
2014-08-01
A study was conducted to investigate the effects of a diet particle size on nutrient digestibility in cows in early lactation. Treatments were diets with forage to concentrate ratio 43:57% in diet dry matter, with four different physically effective fibres (peNDF) content based on different cut length of corn silage and alfalfa haylage. The physical effectiveness factors (pef) and peNDF content of TMRs (total mixed ration) were determined using Penn State Particle Separator (PSPS) with two (pef8.0 , peNDF8.0) or three (pef1.18, peNDF1.18) sieves. The reducing of cut length of forages and particle size of diets did not affect on dry matter intake, while decreased peNDF intake by 16.34 and 8.83%, for peNDF8.0 and peNDF1.18 respectively. Apparent total tract digestibility of the nutrients was measured using two indicators: acid insoluble ash (AIA) and acid detergent insoluble lignin (ADL). Decreasing of forages cut length significantly increased apparent total tract digestibility of neutral detergent fibre (NDF) from 48.39% to 53.84% and from 53.9% to 58.66%, of crude protein from 73.96% to 79.24% and from 71.56% to 77.90%, with contemporary decreasing of non-fibre carbohydrate from 90.89% to 84.81% and from 91.99% to 86.80%, with AIA or ADL as indicator respectively. Dietary value of net energy for lactation (NEL) and energy intake was not affected by the peNDF content of the diet. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hurtubise, R.J.; Allen, T.W.; Hussain, A.
1981-03-29
Dry-column chromatography with an aluminum oxide stationary phase and a n-hexane-ether (19:1) mobile phase was used to separate polycyclic aromatic hydrocarbons (PAH) by ring size. Prior to the dry-column chromatography step, the coal derived solvents were added to an acid treated silica gel column and eluted with chloroform. This step removed pyridine-type nitrogen heterocycles. After separation of the individual ring fractions, the fractions were further separated by either thin layer chromatography (TLC) or high performance liquid chromatography (HPLC). If TLC was used, then after separation fluorescence profiles of each PAH ring fraction distributed on 30%-acetylated cellulose chromatoplates were obtained withmore » a spectrodensitometer. Measurement of fluorescence peak heights gave an approximate measure of the amount of the 3-, 4-, 5-, and 6- ring PAH. For HPLC separation, the 3- and 4- ring PAH fractions obtained from the dry-column chromatography step were separated with a ..mu..-Bondapak C/sub 18/ column and methanol:water (65:35) mobile phase. The HPLC separated PAH were characterized by chromatographic correlation factors and corrected fluorescence excitation spectra. Alkylphenols were identified in coal recycle solvent sample following separation by HPLC.« less
Kukula-Koch, Wirginia; Mroczek, Tomasz
2015-03-01
A rapid hydrostatic counter-current chromatography-thin-layer chromatography-electrospray-ionization time-of-flight mass spectrometry (CCC-TLC-ESI-TOF-MS) technique was established for use in seeking potent anti-Alzheimer's drugs among the acethylcholinesterase inhibitors in Argemone mexicana L. underground parts, with no need to isolate components in pure form. The dichloromethane extract from the roots of Mexican prickly poppy that was most rich in secondary metabolites was subjected to hydrostatic-CCC-based fractionation in descending mode, using a biphasic system composed of petroleum ether-ethyl acetate-methanol-water at the ratio of 1.5:3:2.1:2 (v/v). The obtained fractions were analyzed in a TLC-based AChE-inhibition "Fast Blue B" test. All active components in the fractions, including berberine, protopine, chelerithrine, sanguinarine, coptisine, palmatine, magnoflorine, and galanthamine, were identified in a direct TLC-HPLC-ESI-TOF-MS assay with high accuracy. This is the first time galanthamine has been reported in the extract of Mexican prickly poppy and the first time it has been identified in any member of the Papaveraceae family, in the significant quantity of 0.77%.
Sun, Yanjun; Sun, Yinshi; Chen, Hui; Hao, Zhiyou; Wang, Junmin; Guan, Yanbin; Zhang, Yanli; Feng, Weisheng; Zheng, Xiaoke
2014-10-15
Two new prenylated flavonoids, sinoflavonoids A-B, were isolated from the dried fruits of Sinopodophyllum emodi by silica gel column chromatography (SGCC) and high-speed counter-current chromatography (HSCCC). The 95% ethanol extract was partitioned with petroleum ether, dichloromethane, ethyl acetate, and n-butanol in water, respectively. The ethyl acetate fraction was pre-separated by SGCC with a petroleum ether-acetone gradient. The eluates containing target compounds were further separated by HSCCC with n-hexane-ethyl acetate-methanol-water (4:6:4:4, v/v). Finally, 17.3mg of sinoflavonoid A and 25.9mg of sinoflavonoid B were obtained from 100mg of the pretreated concentrate. The purities of sinoflavonoid A and sinoflavonoid B were 98.47% and 99.38%, respectively, as determined by HPLC. Their structures were elucidated on the basis of spectroscopic evidences (HR-ESI-MS, (1)H-NMR, (13)C-NMR, HSQC, HMBC). The separation procedures proved to be efficient, especially for trace prenylated flavonoids. Copyright © 2014 Elsevier B.V. All rights reserved.
On the radiation stability of crown ethers in ionic liquids.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shkrob, I.; Marin, T.; Dietz, M.
2011-04-14
Crown ethers (CEs) are macrocyclic ionophores used for the separation of strontium-90 from acidic nuclear waste streams. Room temperature ionic liquids (ILs) are presently being considered as replacements for traditional molecular solvents employed in such separations. It is desirable that the extraction efficacy obtained with such solvents should not deteriorate in the strong radiation fields generated by decaying radionuclides. This deterioration will depend on the extent of radiation damage to both the IL solvent and the CE solute. While radiation damage to ILs has been extensively studied, the issue of the radiation stability of crown ethers, particularly in an ILmore » matrix, has not been adequately addressed. With this in mind, we have employed electron paramagnetic resonance (EPR) spectroscopy to study the formation of CE-related radicals in the radiolysis of selected CEs in ILs incorporating aromatic (imidazolium and pyridinium) cations. The crown ethers have been found to yield primarily hydrogen loss radicals, H atoms, and the formyl radical. In the low-dose regime, the relative yield of these radicals increases linearly with the mole fraction of the solute, suggesting negligible transfer of the excitation energy from the solvent to the solute; that is, the solvent has a 'radioprotective' effect. The damage to the CE in the loading region of practical interest is relatively low. Under such conditions, the main chemical pathway leading to decreased extraction performance is protonation of the macrocycle. At high radiation doses, sufficient to increase the acidity of the IL solvent significantly, such proton complexes compete with the solvent cations as electron traps. In this regime, the CEs will rapidly degrade as the result of H abstraction from the CE ring by the released H atoms. Thus, the radiation dose to which a CE/IL system is exposed must be maintained at a level sufficiently low to avoid this regime.« less
McKernan, Moira A.; Rattner, Barnett A.; Hatfield, Jeff S.; Hale, Robert C.; Ottinger, Mary Ann
2010-01-01
We recently reported that air cell administration of penta-brominated diphenyl ether (penta-BDE; DE-71) evokes biochemical and immunologic effects in chicken (Gallus gallus) embryos at very low doses, and impairs pipping (i.e., stage immediately prior to hatching) and hatching success at 1.8 ug g-1 egg (actual dose absorbed) in American kestrels (Falco sparverius). I n the present study, absorption of polybrominated diphenyl ether (PBDE) congeners was measured following air cell administration of a penta-BDE mixture (11.1 ug DE-71 g-1 egg) or an octa-brominated diphenyl ether mixture (octa-BDE; DE-79; 15.4 ug DE-79 g-1 egg). Uptake of PBDE congeners was measured at 24 h post-injection, midway through incubation, and at pipping in chicken, mallard (Anas platyrhynchos), and American kestrel egg contents, and at the end of incubation in black-crowned night-heron (Nycticorax nycticorax) egg contents. Absorption of penta-BDE and octa-BDE from the air cell into egg contents occurred throughout incubation; at pipping, up to 29.6% of penta-BDE was absorbed, but only 1.40-6.48% of octa-BDE was absorbed. Higher brominated congeners appeared to be absorbed more slowly than lower brominated congeners, and uptake rate was inversely proportional to the log Kow of predominant BDE congeners. Six congeners or co-eluting pairs of congeners were detected in penta-BDE-treated eggs that were not found in the dosing solution suggesting debromination in the developing embryo, extraembryonic membranes, and possibly even in the air cell membrane. This study demonstrates the importance of determining the fraction of xenobiotic absorbed into the egg following air cell administration for estimation of the lowest-observed-effect level.
Trans-ethyl methyl ether, the struggle for the detection of a complex molecule in hot cores
NASA Astrophysics Data System (ADS)
Fuchs, G. W.; Fuchs, U.; Giesen, T. F.; Wyrowski, F.
Many large and complex molecules of prebiotic importance have been found as constituents of interstellar clouds but their detection remains difficult and sometimes doubtful (Snyder et al. 2005). The complex spectrum of trans-ethyl methyl ether (EME) has been investigated in the laboratory (Fuchs et al. 2003) up to 350 GHz and is now known with high frequency precision, see Figure 1. In this work we present an extensive search for EME towards G34.26, NGC6334(I), Orion KL, SgrB2(N) and W51e2 in the 1 to 3 mm wavelength region. These sources have previously been shown to have a rich chemistry of complex molecules. The IRAM 30m telescope at Pico Veleta, Spain and the SEST 15m radio telescope in La Silla, Chile have been used for the observations. We looked at 5 - 11 frequency bands where EME has strong transitions. All sources were examined using long integration times up to 220 min (on+off), elevations greater 40◦ and under good weather conditions. For our analysis of the data we used the method of rotational-temperature-diagrams but also the myXCLASS (written by Peter Schilke) extension program to the GILDAS (Grenoble Image and Line Data Analysis Software) software which enabled us to simulate spectra of several molecules including their linewidth and intensities at the same time, see Figure 2. With this program a consistency check of molecular abundances and overall composition is possible even in dense spectra with many overlapping lines. The effect of the source size on the measured intensities has been considered and cross checks with other important molecules such as methanol, ethanol and di-methyl ether have been performed. Charnley et al. (2001) assigned one line in W51 e1/e2 and one line in Orion KL at 160.1 GHz, as well as a line in SgrB2(N) at 79.6 GHz to trans-ethyl methyl ether. From their isolated measurements, the column density of EME was estimated to be in the range 1014-1015 cm-2 in Sgr B2(N) corresponding to a fractional abundance of 10-10-10-9 and in the W51 region they estimate a fractional abundance of 10-10. However, our observations cannot confirm the tentative detection of EME in Orion KL within their given column density limits. There is evidence for the existence of the trans-ethyl methyl ether towards W51e2 with a column density of N=2×1014 cm-2 based on the detection of 14 lines which coincide with EME transition frequencies. We present new upper limits of 7-8×1013 cm-2 for the column densities of EME toward Orion KL, G34.26, NGC6334(I) and estimate the column density of SgrB2(N) to be of the same order. The W51e2 observations are discussed in more detail.
Benneh, Charles Kwaku; Biney, Robert Peter; Mante, Priscilla Kolibea; Tandoh, Augustine; Adongo, Donatus Wewura; Woode, Eric
2017-07-31
Maerua angolensis DC (Capparaceae) has been employed in the management of several central nervous system (CNS) disorders including anxiety. This study evaluated the anxiolytic effects of the petroleum ether/ethyl acetate fraction stem bark extract and its possible mechanism(s) using zebrafish anxiety models. Adult zebrafish, tested in the novel tank and light dark tests, have shown by previous authors to be sensitive to the anxiolytic effects of known anxiolytic drugs. Adult zebrafish were treated with M. angolensis extract, fluoxetine, desipramine, and diazepam followed by testing in the novel tank and light dark tests. We further assessed the effect of the extract on anxiety after inducing an anxiogenic phenotype using the ethanol-withdrawal and chronic unpredictable stress (CUS) tests. The anxiolytic effect was further investigated after pretreatment with flumazenil, granisetron, cyproheptadine, methysergide and pizotifen. M. angolensis extract, similar to fluoxetine and desipramine, demonstrated significant anxiolytic behaviour at doses that did not reduce locomotor activity significantly. Similar anxiolytic effects were recorded in the ethanol withdrawal-induced anxiety test. Furthermore, the anxiogenic effects induced by the CUS paradigm were significantly reversed by treatment M. angolensis extract and fluoxetine. The anxiolytic effects of M. angolensis extract were however reversed after pre-treatment with flumazenil, granisetron, cyproheptadine, methysergide and pizotifen. Taken together, this suggests that the petroleum ether/ ethyl acetate fraction of M. angolensis possesses significant anxiolytic activity, which could partly be accounted for by an interaction with the serotoninergic system and the GABA A receptor. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Singh, Namrata; Bhattacharyya, Debasish
2016-04-15
An ether extract of nine different bacterial metabolites in combination with two solvent extract (ether followed by ethanol) of bile lipids from ox gall bladder is used as an immune stimulator drug. Over the years bile acids are discussed regarding their anti-oxidant and lipid peroxidation properties. Since some of the bile acids are known to be potent antioxidants, presence of similar activity in the solvent extract of ox bile lipid was investigated using TLC and reverse phase HPLC systems. Fractions from HPLC were analyzed with mass spectrometry using electrospray ionization. The presence of twelve different bile acids along with other substances in small proportions including fatty acids, sulfate conjugates and bile pigments were confirmed. The twelve separated peaks had similar retention times as those of tauroursodeoxycholic acid, glycoursodeoxycholic acid, taurocholic acid, glycocholic acid, glycochenodeoxycholic acid, taurochenodeoxycholic acid, taurodeoxycholic acid, cholic acid, ursodeoxycholic acid, chenodeoxycholic acid, deoxycholic acid, and lithocholic acid. Subsequently, all fractions were tested for their anti-oxidative property on HepG2 cells exposed to H2O2 that served as an oxidative injury model. Four fluorescent dyes H2DCF DA, MitoSOX red, Amplex red and DAF-2 DA were used for estimation of reactive radicals in the HepG2 cells. Among the separated bile acids, tauroursodeoxycholic acid, glycoursodeoxycholic acid and ursodeoxycholic acid prevented the HepG2 cells from H2O2-induced oxidative stress. Copyright © 2015 Elsevier B.V. All rights reserved.
Bouzidi, Amel; Benzarti, Anissa; Arem, Amira El; Mahfoudhi, Adel; Hammami, Saoussen; Gorcii, Mohamed; Mastouri, Maha; Hellal, Ahmed Noureddine; Mighri, Zine
2016-07-01
In the present investigation, extracts obtained from L. guyonianum Durieu ex Boiss. aerial parts were used to evaluate total phenolic, flavonoid and tannin contents. A study of antioxidant activities of the prepared samples was carried out on the basis of 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2-2'-azino-bis-(3-ethylbenz-thiazoline-6-sulfonic acid) (ABTS+.) and ferric reducing antioxidant power (FRAP) assays. Moreover, the efficiency of methanolic, chloroformic and petroleum ether extracts and the deriving fractions from the methanolic extract was tested against human bacterial and fungal pathogenic strains using micro dilution method in 96 multiwell microtiter plate. Furthermore, leaves and stems extracts were subjected to RP-HPLC for phenolic compounds identification. Results showed that polyphenolic contents and antioxidant activities varied considerably as function of solvent polarity. Moreover, antiradical capacities against DPPH, ABTS(+.) and reducing power were maxima in methanol aerial parts extract which showed the highest polyphenol contents (134mg CE/g DW). The antimicrobial activities showed that methanolic, chloroformic and petroleum ether extracts were found to be most potent against Pseudomonas aeruginosa and Staphylococcus aureus with MIC values of 23 and 46μ.mL(-1), respectively. The fractions F(13) and F(16) have a great antifungal potential against Candida glabrata, Candida krusei and Candida parapsilesis (MIC=39μ.mL(-1)). The RP-HPLC analysis lead the identification of gallic, procatechuic and trans-cinnamic acids, methyl-4-hydroxybenzoate, n-propyl-3,4,5-trihydroxybenzoate, epicatechin, naringin and myricetin in L. guyonianum Durieu ex Boiss. leaves and stems extracts.
40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Monomethyl Ether *Dimer Acids Dioxane Ethane Ethylene Glycol Monophenyl Ether *Ethoxylates, Misc. Ethylene Glycol Dimethyl Ether Ethylene Glycol Monobutyl Ether Ethylene Glycol Monoethyl Ether Ethylene Glycol...
Bano, Shaista; Siddiqui, Bina Shaheen; Farooq, Ahsana Dar; Begum, Sabira; Siddiqui, Faheema; Kashif, Muhammad; Azhar, Mudassar
2017-12-01
Several Euphorbia species have been used in folklore as cancer remedies, however, scientific studies on the cytotoxicity (in vitro studies) of Euphorbia caducifolia are lacking. In present study, anticancer potential of E. caducifolia aerial parts ethanol extract and its fractions were evaluated against human lung (NCI-H460), breast (MCF-7), prostate (PC-3) and cervical (HeLa) cancer cell lines, using sulphorhodamine-B in vitro cytotoxicity (in vitro studies) assay. The ethanol extract demonstrated growth inhibitory effect against all aforementioned cancer cell lines with IC 50 , 19-135 μg/mL and LC 50 , ~220 μg/mL, and its petroleum ether fraction obtained on bioactivity guided fraction showed highest activity with IC 50 , 28-70 μg/mL and LC 50 , 71 μg/mL against NCI-H460 and MCF-7 cell lines. Its phytochemicals were analysed by gas chromatography-mass spectrometry (GC-MS). The present study provides scientific justification for its traditional use against cancer.
Wang, Xiaohong; Liang, Yong; Peng, Cuilin; Xie, Huichun; Pan, Man; Zhang, Tianyou; Ito, Yoichiro
2010-01-01
Combined with medium-pressure liquid chromatography (MPLC) and preparative high-pressure liquid chromatography (Prep-HPLC), high-speed countercurrent chromatography (HSCCC) was successfully applied for separation and purification of isoflavonoids from the extract of belamcanda. HSCCC separation was performed on a two-phase solvent system composed of methyl tert-butyl ether -ethyl acetate - n-butyl alcohol – acetonitrile −0.1% aqueous trifluoroacetic acid at a volume radio of 1:2:1:1:5. Semi-purified peak fractions from HSCCC separation were further purified by Prep-HPLC. Nine well-separated fractions were analyzed by HPLC-UV absorption spectrometry to determine their purities and characterized with ESI-MSn. Except for peaksland VII (unknown) seven compounds were identified as apocynin (peak II), mangiferin (peak III), 7-O-methylmangiferin (peak IV), hispidulin (peak V), 3′-hydroxyltectoridin (peak VI), iristectorin B (peak VII), isoiridin (peak IX). PMID:21552369
Shen, Bingbing; Zhou, Rongrong; Yang, Yupei; Li, Jiayu; Liang, Xuejuan; Chen, Lin; Huang, Luqi; Zhang, Shuihan
2018-04-03
This paper intends to identify the antimicrobial activity compounds from the deciduous leaves of Malus doumeri (Dong Li Tea) by HPLC-ESI-QTOF-MS/MS. The ethanol extracts of Malus doumeri were partitioned into petroleum ether, dichloromethane, ethyl acetate, n-butanol and water fraction, respectively. The antimicrobial screening experiments showed that ethyl acetate fraction has a certain antibacterial activity by inhibition zone method in vitro. And then we used the HPLC-ESI-QTOF-MS/MS method to verify the identities of bioactive compounds. Finally, 41 compounds were determined and 11 of which were firstly reported in this plant. Notably, compounds (32, 34, 38) are new dihydrochalcones, and three chlorogenic acid analogues (10, 13, 17) may be potential antimicrobial active ingredient. Which is of great significance to the isolation of novel compounds and the discovery of new natural preservative candidates from the deciduous leaves of Malus doumeri.
Vit, Patricia; Santiago, B
2008-12-01
Venezuelan bee pollen has not been characterized, and marketing is not regulated. Pollen is consumed for apitherapeutical purposes for its nutritional and medicinal properties. This product of the hive is the most popular after honey; therefore it is necessary to characterize and to value it to initiate a database to support the proposal of a norm for bee pollen quality control. Samples of bee pollen collected by bees in the Misintá páramo of Mérida state were characterized accoridng to the chemical composition (moisture, ash, fat, pH, proteins) of four color fractions (yellow, orange, ochre, green). Yellow pollen was the most frequent fraction, with 2.18 g ash/100 g, 5.37 g ether extract/100 g, 14.88 g moisture/100 g, and 37.32 g proteins/100 g.
Molecular structure impacts on secondary organic aerosol formation from glycol ethers
NASA Astrophysics Data System (ADS)
Li, Lijie; Cocker, David R.
2018-05-01
Glycol ethers, a class of widely used solvents in consumer products, are often considered exempt as volatile organic compounds based on their vapor pressure or boiling points by regulatory agencies. However, recent studies found that glycol ethers volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents indicating the potential of glycol ethers to form secondary organic aerosol (SOA). This is the first work on SOA formation from glycol ethers. The impact of molecular structure, specifically -OH, on SOA formation from glycol ethers and related ethers are investigated in the work. Ethers with and without -OH, with methyl group hindrance on -OH and with -OH at different location are studied in the presence of NOX and under "NOX free" conditions. Photooxidation experiments under different oxidation conditions confirm that the processing of ethers is a combination of carbonyl formation, cyclization and fragmentation. Bulk SOA chemical composition analysis and oxidation products identified in both gas and particle phase suggests that the presence and location of -OH in the carbon bond of ethers determine the occurrence of cyclization mechanism during ether oxidation. The cyclization is proposed as a critical SOA formation mechanism to prevent the formation of volatile compounds from fragmentation during the oxidation of ethers. Glycol ethers with -CH2-O-CH2CH2OH structure is found to readily form cyclization products, especially with the presence of NOx, which is more relevant to urban atmospheric conditions than without NOx. Glycol ethers are evaluated as dominating SOA precursors among all ethers studied. It is estimated that the contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources. The contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources and will play a more important role in future anthropogenic SOA formation.
Cost analysis and environmental impact of nonthermal technologies
USDA-ARS?s Scientific Manuscript database
The cost of high pressure processing (HPP) orange juice and its environmental impact were estimated. In addition, the environmental impact of pulsed electric fields (PEF) and thermal pasteurization were assessed for comparison. The cost analysis was based on commercial processing conditions that wer...
Gibbilimbols A-D, cytotoxic and antibacterial alkenylphenols from Piper gibbilimbum.
Orjala, J; Mian, P; Rali, T; Sticher, O
1998-07-01
Fractionation of the petroleum ether extract from the leaves of Piper gibbilimbum collected in Papua New Guinea afforded four new alkenylphenols, gibbilimbols A-D (1-4). The structures of the isolates were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR spectroscopy. Gibbilimbols A-D were found to be toxic to brine shrimp with an LC50 of approximately 5 microg/mL. Gibbilimbols A-D were further found to be cytotoxic toward KB nasopharyngal carcinoma cells (ED50 7.8-2.1 microg/mL). All isolates also showed antibacterial activity toward Staphylococcus epidermidis and Bacillus cereus.
1990-10-16
washed with concentrated sulfuric acid , then with water, dried over anhydrous magnesium sulfate, refluxed over calcium hydride and freshly distilled...oxide, filtered, and fractionally distilled under reduced pressure. Trifluoromethane sulfonic acid (triflic acid , 98%, Aldrich) w s distilled under...flask. Then the flask was filled with argon, cooled to 0°C and the methylene chloride, dimethyl sulfide and triflic acid were added via a syringe. The
Zhuang, Yuan; Ahn, Sungwoo; Seyfferth, Angelia L.; Masue-Slowey, Yoko; Fendorf, Scott; Luthy, Richard G.
2011-01-01
Nanoscale zerovalent iron particles (nZVI), bimetallic nanoparticles (nZVI/Pd), and nZVI/Pd impregnated activated carbon (nZVI/Pd-AC) composite particles were synthesized and investigated for their effectiveness to remove polybrominated diphenyl ethers (PBDEs) and/or polychlorinated biphenyls (PCBs). Palladization of nZVI promoted the dehalogenation kinetics for mono- to tri-BDEs and 2,3,4-trichlorobiphenyl (PCB 21). Compared to nZVI, the iron-normalized rate constants for nZVI/Pd were about 2-, 3-, and 4-orders of magnitude greater for tri-, di-, and mono-BDEs, respectively, with diphenyl ether as a main reaction product. The reaction kinetics and pathways suggest an H-atom transfer mechanism. The reaction pathways with nZVI/Pd favor preferential removal of para-halogens on PBDEs and PCBs. X-ray fluorescence mapping of nZVI/Pd-AC showed that Pd mainly deposits on the outer part of particles, while Fe was present throughout the activated carbon particles. While BDE 21 was sorbed onto activated carbon composites quickly, debromination was slower compared to reaction with freely dispersed nZVI/Pd. Our XPS and chemical data suggest about 7% of the total iron within the activated carbon was zero-valent, which shows the difficulty with in-situ synthesis of a significant fraction of zero-valent iron in the micro-porous material. Related factors that likely hinder the reaction with nZVI/Pd-AC are the heterogenous distribution of nZVI and Pd on activated carbon and/or immobilization of hydrophobic organic contaminants at the adsorption sites thereby inhibiting contact with nZVI. PMID:21557574
Impact of airway gas exchange on the multiple inert gas elimination technique: theory.
Anderson, Joseph C; Hlastala, Michael P
2010-03-01
The multiple inert gas elimination technique (MIGET) provides a method for estimating alveolar gas exchange efficiency. Six soluble inert gases are infused into a peripheral vein. Measurements of these gases in breath, arterial blood, and venous blood are interpreted using a mathematical model of alveolar gas exchange (MIGET model) that neglects airway gas exchange. A mathematical model describing airway and alveolar gas exchange predicts that two of these gases, ether and acetone, exchange primarily within the airways. To determine the effect of airway gas exchange on the MIGET, we selected two additional gases, toluene and m-dichlorobenzene, that have the same blood solubility as ether and acetone and minimize airway gas exchange via their low water solubility. The airway-alveolar gas exchange model simulated the exchange of toluene, m-dichlorobenzene, and the six MIGET gases under multiple conditions of alveolar ventilation-to-perfusion, VA/Q, heterogeneity. We increased the importance of airway gas exchange by changing bronchial blood flow, Qbr. From these simulations, we calculated the excretion and retention of the eight inert gases and divided the results into two groups: (1) the standard MIGET gases which included acetone and ether and (2) the modified MIGET gases which included toluene and m-dichlorobenzene. The MIGET mathematical model predicted distributions of ventilation and perfusion for each grouping of gases and multiple perturbations of VA/Q and Qbr. Using the modified MIGET gases, MIGET predicted a smaller dead space fraction, greater mean VA, greater log(SDVA), and more closely matched the imposed VA distribution than that using the standard MIGET gases. Perfusion distributions were relatively unaffected.
Matsumiya, Y; Murata, N; Tanabe, E; Kubota, K; Kubo, M
2010-06-01
To degrade ether-type polyurethane (ether-PUR), ether-PUR-degrading micro-organism was isolated. Moreover, ether-PUR-degrading mechanisms were analysed using model compounds of ether-PUR. A fungus designated as strain PURDK2, capable of changing the configuration of ether-PUR, has been isolated. This isolated fungus was identified as Alternaria sp. Using a scanning electron microscope, the grid structure of ether-PUR was shown to be melted and disrupted by the fungus. The degradation of ether-PUR by the fungus was analysed, and the ether-PUR was degraded by the fungus by about 27.5%. To analyse the urethane-bond degradation by the fungus, a degraded product of ethylphenylcarbamate was analysed using GC/MS. Aniline and ethanol were detected by degradation with the supernatant, indicating that the fungus secreted urethane-bond-degrading enzyme(s). PURDK2 also degraded urea bonds when diphenylmethane-4,4'-dibutylurea was used as a substrate. The enzyme(s) from PURDK2 degraded urethane and urea bonds to convert the high molecular weight structure of ether-PUR to small molecules; and then the fungus seems to use the small molecules as an energy source. Ether-PUR-degrading fungus, strain PURDK2, was isolated, and the urethane- and urea-bonds-degrading enzymes from strain PURDK2 could contribute to the material recycling of ether-PUR.
[Physical activity and respiratory function: corporal composition and spirometric values analysis].
Paulo, Rui; Petrica, João; Martins, Júlio
2013-01-01
The main aim of this research project was to measure the effects of physical activity on corporal composition (BMI and waist circumference) on spirometric values and relate these indicators to the respiratory/ventilator function. The sample consisted of 86 individuals, higher education students, with an average age of 21.3 ± 2.4 years, who were divided into two groups: the control group consisted of 28 sedentary subjects (20.9 ± 1.3 years), and the experimental group consisting of 58 subjects (21.5 ± 2.8 years) who undertook supervised exercise. To characterize the sample of the type of physical activity, we used an adaptation of the questionnaire Telama et al.19 We assessed the value of spirometry (PEF, FVC and FEV₁) with a Microquark Cosmed spirometer and the BMI and waist circumference. The figures obtained were processed with the S.P.S.S. 19.0, the t-test, the Levene test, the Mann-Whitney test and the Spearman correlation test, adopting a significance level of 5%. The experimental group achieved significantly better BMI and waist circumference results (p = 0.05) and in all of the values assessed by spirometry (PEF, FVC and FEV₁) compared to the control group. We also found that there is a tendency for a negative correlation between the values of body composition and spirometric values, only observable in some variables (PEF, FEV₁), i.e., the higher the values of body composition, the lower the spirometric values. The students that performed supervised exercise had higher levels of body composition and lung function. Poor BMI and waist circumference values may lead to respiratory dysfunction in terms of ventilation and the respective lung volumes, limiting the practice of physical activity and increasing the probability of respiratory pathologies.
Toward two-photon excited fluorescence lifetime endomicroscopy (Conference Presentation)
NASA Astrophysics Data System (ADS)
Hage, Charles-Henri; Leclerc, Pierre; Fabert, Marc; Brevier, Julien; Habert, Rémi; Braud, Flavie; Kudlinski, Alexandre; Louradour, Frédéric
2017-02-01
Fluorescence lifetime imaging microscopy (FLIM) represents a powerful tool for biological studies. Endoscopic FLIM applied to the intracellular native biomarker NADH and FAD represents a promising mean for in vivo in situ malignant tissue diagnosis in the medical field. Else, 2-photon-excited fluorescence (2PEF) provides increased 3D resolution and imaging depth. But very few demonstrations about 2PEF lifetime measurement through a fiber have been reported and none about endoscopic 2P-FLIM through a practical fiber length (< 3m). Our group has recently demonstrated the possibility to efficiently deliver through a very long optical fiber the short and intense excitation pulses required for 2P-FLIM. Our goal is now to check that collecting fluorescence through the same endoscopic fiber does not deteriorate the lifetime measurement. Relying on the basis previously published in case of 1PEF by P. French and co-workers (J. Biophotonics, 2015), we have experimentally quantitatively evaluated the influence on the lifetime measurement of the fiber chromatic and intermodal dispersions. The main result is that the fiber contribution to the system impulse response function, even in the case of a 3-meter long double-clad optical fiber, does not hinder the separation between free and bound NADH states using FLIM. Related calibrations and measurements will be detailed. Ongoing experiments about the development of a 2P-FLIM endomicroscope on the basis of an previously reported 2P-endomicroscope (Ducourthial et al., Sc. Reports, 2015), used under various configurations (i.e. point measurement in the center of the 2P-endomicroscope image, averaged lifetime, binned endoscopic 2P-FLIM image), will be also presented.
Zhong, C; Yang, W; Li, Y; Zou, L; Deng, Z; Liu, M; Huang, X
2018-05-01
The efficacy and safety of sublingual immunotherapy (SLIT) in house dust mite-induced allergic asthma (AA) have yet to be firmly established, especially in adult patients. Our objective is to evaluate the efficacy of SLIT with Dermatophagoides farinae drops in adult patients with AA. One hundred and thirty-four adult patient data with house dust mite (HDM)-induced AA who had been treated for 2 years were collected. These patient data that we collected were divided into the SLIT group (n = 85) and control group (n = 49). All patients were treated with low to moderate dose of inhaled glucocorticoid and long-acting β2 agonists. Patients in the SLIT group were further treated with D. farinae drops. Clinical scores including the total asthma symptom score (TASS), total asthma medicine score (TAMS), asthma control test (ACT), and peak flow percentage (PEF%) were assessed before treatment and at yearly visits. The presence of adverse events (AEs) were recorded once a month. Before treatment, the PEF% in the SLIT group was significantly lower than that in the control group (p < 0.05). After 2 years, both treatments were effective in the clinical scores when compared with baseline values (all p < 0.001). Meanwhile, the SLIT group showed significantly lower TASS and TAMS (all p < 0.001) and higher ACT (p < 0.001) and PEF% (p < 0.05) when compared with the control group. No severe systemic AEs were reported. SLIT with D. farinae drops plus pharmacotherapy is more effective than routine drug treatment in adult patients with AA.
NASA Astrophysics Data System (ADS)
Min, Sun-Hong; Kwon, Ohjoon; Sattorov, Matlabjon; Baek, In-Keun; Kim, Seontae; Jeong, Jin-Young; Hong, Dongpyo; Park, Seunghyuk; Park, Gun-Sik
2017-01-01
Non-thermal irreversible electroporation (NTIRE) to avoid thermal damage to cells during intense DC ns pulsed electric fields (nsPEFs) is a recent modality for medical applications. This mechanism, related to bioelectrical dynamics of the cell, is linked to the effect of a DC electric field and a threshold effect with an electrically stimulated membrane for the charge distribution in the cell. To create the NTIRE condition, the pulse width of the nsPEF should be shorter than the charging time constant of the membrane related to the cell radius, membrane capacitance, cytoplasm resistivity, and medium resistivity. It is necessary to design and fabricate a very intense nanosecond DC electric field pulser that is capable of producing voltages up to the level of 100 kV/cm with an artificial pulse width (˜ns) with controllable repetition rates. Many devices to generate intense DC nsPEF using various pulse-forming line technologies have been introduced thus far. However, the previous Blumlein pulse-generating devices are clearly inefficient due to the energy loss between the input voltage and the output voltage. An improved two-stage stacked Blumlein pulse-forming line can overcome this limitation and decrease the energy loss from a DC power supply. A metal oxide silicon field-effect transistor switch with a fast rise and fall time would enable a high repetition rate (max. 100 kHz) and good endurance against very high voltages (DC ˜ 30 kV). The load is designed to match the sample for exposure to cell suspensions consisting of a 200 Ω resistor matched with a Blumlein circuit and two electrodes without the characteristic RC time effect of the circuit (capacitance =0.174 pF).
Li, Lin-Wei; Huang, Ying; Luo, Rong; Yan, Li; Li, Qu-Bei; Peng, Dong-Hong; Shu, Chang
2015-03-01
To observe the efficacy of regular or intermittent inhalation of salmeterol/fluticasone propionate (SM/FP) in the treatment of bronchial asthma and its effects on growth and development in children. A total of 112 children diagnosed with bronchial asthma between September 2012 and October 2013 were assigned to standardized treatment (standard group, n=56) and non-standardized treatment (intermittent group, n=56). Comparisons of clinical symptom scores and main pulmonary function indicators between the two groups were carried out before treatment and at 6 and 12 months after treatment. The growth velocity and changes in body mass index (BMI) were observed in the two groups. At 6 and 12 months after the treatment, the standard group had significantly reduced clinical symptom scores and significantly increased pulmonary function indicators (percentage of predicted peak expiratory flow, PEF%; percentage of forced expiratory volume in 1 second, FEV1%) (P<0.05); the intermittent group had significantly reduced clinical symptom scores and significantly increased FEV1% (P<0.05), but PEF% was significantly increased only at 6 months after treatment (P<0.05). At 12 months after treatment, the standard group had significantly lower clinical symptom scores and significantly higher PEF% and FEV1% when compared with the intermittent group (P<0.05). The growth velocity and BMI showed no significant differences between the two groups at 6 and 12 months after treatment (P>0.05). Compared with intermittent inhalation, long-term regular inhalation of SM/FP performs better in controlling clinical symptoms and enhancing pulmonary function in children with asthma. Inhalation of SM/FP for one year reveals no apparent effect on the growth and development of these children.
Flores, Nelly; Sharif, Farbod; Yasri, Nael; Brillas, Enric; Sirés, Ignasi; Roberts, Edward P L
2018-06-01
This work compares the ability of physical and chemical treatments, namely adsorption and electrochemical advanced oxidation processes, to remove tyrosol from aqueous medium. Adsorption on graphene nanoplatelets (GNPs) performed much better than that with a graphite intercalation compound. Adsorption isotherms were found to follow the Freundlich model (R 2 = 0.96), which is characteristic of a chemisorption process. Successful electrochemical regeneration enables 5 successive adsorption/regeneration cycles before corrosion of GNPs occurs. Other typical aromatic contaminants that may coexist with tyrosol can be also adsorbed on GNPs. Percentage of regeneration efficiency of GNPs showed a higher affinity towards Lewis acids group compounds and a lower one towards Lewis base. The treatment of 100 mL of 0.723 mM tyrosol solutions in non-chlorinated and chlorinated matrices at pH 3.0 was carried out by electrochemical oxidation with electrogenerated H 2 O 2 (EO-H 2 O 2 ), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF). Trials were made with a BDD anode and an air-diffusion cathode at 10-30 mA cm -2 . Hydroxyl radicals formed at the anode from water oxidation and/or in the bulk from Fenton's reaction between added Fe 2+ and generated H 2 O 2 , along with active chlorine produced in chlorinated medium, were the main oxidants. Tyrosol concentration always decayed following a pseudo-first-order kinetics and its mineralization rose as EO-H 2 O 2 < EF < PEF, more rapidly in the chlorinated matrix. The potent photolysis of intermediates under UVA radiation explained the almost total mineralization achieved by PEF in the latter medium. The effect of current density and tyrosol content on the performance of all processes was examined. Copyright © 2018 Elsevier Ltd. All rights reserved.
Shi, Jun-Wen; Liu, Wei; Zhang, Ting-Ting; Wang, Sheng-Chun; Lin, Xiao-Lin; Li, Jing; Jia, Jun-Shuang; Sheng, Hong-Fen; Yao, Zhi-Fang; Zhao, Wen-Tao; Zhao, Zun-Lan; Xie, Rao-Ying; Yang, Sheng; Gao, Fei; Fan, Quan-Rong; Zhang, Meng-Ya; Yue, Min; Yuan, Jin; Gu, Wei-Wang; Yao, Kai-Tai; Xiao, Dong
2013-04-01
In previous studies from other labs it has been well demonstrated that the ectopic expression of c-Myc in mammary epithelial cells can induce epithelial-mesenchymal transition (EMT), whereas in our pilot experiment, epithelial-like morphological changes were unexpectedly observed in c-Myc-expressing pig fibroblasts [i.e., porcine embryonic fibroblasts (PEFs) and porcine dermal fibroblasts (PDFs)] and pig mesenchymal stem cells, suggesting that the same c-Myc gene is entitled to trigger EMT in epithelial cells and mesenchymal-epithelial transition (MET) in fibroblasts. This prompted us to characterize the existence of a MET in c-Myc-expressing PEFs and PDFs at the molecular level. qRT-PCR, immunofluorescence and western blot analysis illustrated that epithelial-like morphological changes were accompanied by the increased expression of epithelial markers [such as cell adhesion proteins (E-cadherin, α-catenin and Bves), tight junction protein occludin and cytokeratins (Krt8 and Krt18)], the reduced expression of mesenchymal markers [vimentin, fibronectin 1 (FN1), snail1, collagen family of proteins (COL1A1, COL5A2) and matrix metalloproteinase (MMP) family (MMP12 and MMP14)] and the decreased cell motility and increased cell adhesion in c-Myc-expressing PEFs and PDFs. Furthermore, the ectopic expression of c-Myc in pig fibroblasts disrupted the stress fiber network, suppressed the formation of filopodia and lamellipodia, and resulted in RhoA/Rock pathway inactivation, which finally participates in epithelial-like morphological conversion. Taken together, these findings demonstrate, for the first time, that the enforced expression of c-Myc in fibroblasts can trigger MET, to which cytoskeleton depolymerization and RhoA/Rock pathway inactivation contribute.