Database : MEDLINE
Search on : D02.455.426.559.389.023 [DeCS Category]
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  1 / 7303 MEDLINE  
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PMID:29175406
Author:Sohn SY; Kuntze K; Nijenhuis I; Häggblom MM
Address:Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, 76 Lipman Drive, New Brunswick, NJ 08901, USA.
Title:Evaluation of carbon isotope fractionation during anaerobic reductive dehalogenation of chlorinated and brominated benzenes.
Source:Chemosphere; 193:785-792, 2018 Feb.
ISSN:1879-1298
Country of publication:England
Language:eng
Abstract:Compound specific stable isotope analysis (CSIA) has been established as a useful tool to evaluate in situ biodegradation. Here, CSIA was used to determine microbial dehalogenation of chloro- and bromobenzenes in microcosms derived from Hackensack River sediments. Gas chromatography-isotope ratio mass spectrometry (GC-IRMS) was used to measure carbon isotope fractionation during reductive dehalogenation of hexachlorobenzene (HCB), pentachlorobenzene (PeCB), 1,2,3,5-tetrachlorobenzene (TeCB), 1,2,3,5-tetrabromobenzene (TeBB), and 1,3,5-tribromobenzene (TriBB). Strong evidence of isotope fractionation coupled to dehalogenation was not observed in the substrate, possibly due to the low solubilities of the highly halogenated benzene substrates and a dilution of the isotope signal. Nonetheless, we could measure a depletion of the δ C value in the dichlorobenzene product during dechlorination of HCB, the sequential depletion and enrichment of δ C value for trichlorobenzene in TeCB dechlorinating cultures, and the enrichment of δ C during debromination of TriBB. This indicates that a measurable isotope fractionation occurred during reductive dehalogenation of highly halogenated chloro- and bromobenzenes in aquatic sediments. Thus, although more quantitative measurements will be needed, the data suggests that CSIA may have application for monitoring in situ microbial reductive dehalogenation of highly halogenated benzenes.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Bromobenzenes); 0 (Carbon Isotopes); 0 (Chlorobenzenes); J64922108F (Benzene)


  2 / 7303 MEDLINE  
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PMID:29180221
Author:Gritti F; Cormier S
Address:Waters Corporation, 34 Maple Street, Milford, MA 01757, USA. Electronic address: Fabrice_Gritti@waters.com.
Title:Performance optimization of ultra high-resolution recycling liquid chromatography.
Source:J Chromatogr A; 1532:74-88, 2018 Jan 12.
ISSN:1873-3778
Country of publication:Netherlands
Language:eng
Abstract:The optimization of a twin-column recycling separation process (TCRSP) for maximum resolution or maximum speed-resolution was investigated. The general optimization method was based on the construction of kinetic plots by assuming an ideal TCRSP (no efficiency loss upon recycling). For the optimization, we examined three chromatographic parameters: operation pressure (3000, 6000, 9000, and 12,000psi), column length (10, 15, and 25cm), and column inner diameter (i.d.) (2.1, 3.0, and 4.6mm). Accordingly, the highest TCRSP resolution level is expected for 25cm long columns packed with 2.5, 2.0, 1.7, and 1.6µm particles at pressures of 3000, 6000, 9000, and 12,000psi, respectively. The maximum speed-resolution performance is expected for 10cm columns packed with 3.7, 3.0, 2.6, and 2.4µm particles. 3.0mm i.d. columns are best to minimize the negative impacts of thermal and inter-column dispersion effects on the TCRSP performance. The method was illustrated for the challenging separation (selectivity factor α<1.02) of small molecules in RPLC at a maximum pressure of 6000psi using commercially available columns. Accordingly, 3.0×150mm columns packed with 2.5µm cellulose-1 Trefoil particles (chiral separation, γ-phenylbutyrolactone, α=1.01, efficiency N=4500) and 2.7µm Cortecs-C particles (isotope separation, α=1.02, N=14, 500) particles were found to be the most suitable columns to maximize speed-resolution performance. Further optimization of the TCRSP performance was required by reducing the inter-column sample dispersion that could cause undesirable peak tailing. A standard 2.4µL Rheodyne valve and 100µm i.d. tubes were replaced with a home-made 0.5µL low-dispersion prototype valve and 75µm i.d. perfect connection tubes. As a result, the experimental resolution factors were increased by +60% (γ-phenylbutyrolactone, 25 cycles, R =0.7→1.1) and +80% (deuterated benzenes, 22 cycles, R =1.1→2.0). Direct comparison between the experimental and the predicted TCRSP performance unambiguously demonstrated that the resolution gain was explained by the significant reduction of the peak tailing after a large number of cycles (n>20).
Publication type:JOURNAL ARTICLE
Name of substance:J64922108F (Benzene)


  3 / 7303 MEDLINE  
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PMID:28992483
Author:Ma J; Yang Y; Jiang X; Xie Z; Li X; Chen C; Chen H
Address:State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China. Electronic address: rubpmj@sina.com.
Title:Impacts of inorganic anions and natural organic matter on thermally activated persulfate oxidation of BTEX in water.
Source:Chemosphere; 190:296-306, 2018 Jan.
ISSN:1879-1298
Country of publication:England
Language:eng
Abstract:The present study investigated the impacts of water matrix constituents (CO , HCO , Cl , Br , PO , HPO , H PO , NO , SO and natural organic matters (NOM) on the oxidation of a mixture of benzene, toluene, ethylbenzene, and xylenes (BTEX) by thermally activated persulfate (PS). In the absence of matrix constituents, the BTEX oxidation rates decreased in the following order: xylenes > toluene ≈ ethylbenzene > benzene. HCO /CO and NOM inhibited the BTEX oxidation and the inhibiting effects became more pronounced as the HCO /CO /NOM concentration increased. SO , NO , PO and H PO did not affect the BTEX oxidation while HPO slightly inhibited the reaction. The impacts of Cl and Br were complex. Cl inhibited the benzene oxidation while 100 mM and 500 mM of Cl promoted the oxidation of m-xylene and p-xylene. Br completely suppressed the benzene oxidation while 500 mM of Br strongly promoted the oxidation of xylenes. Detailed explanations on the influence of each matrix constituent were discussed. In addition, various halogenated degradation byproducts were detected in the treatments containing Cl and Br . Overall, this study indicates that some matrix constituents such as NOM, HCO , CO , H PO , Cl and Br may reduce the BTEX removal efficiency of sulfate radical-based advanced oxidation process (SR-AOP) and the presence of Cl and Br may even lead to the formation of toxic halogenated byproducts.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Benzene Derivatives); 0 (Humic Substances); 0 (Inorganic Chemicals); 0 (Ions); 0 (Sulfates); 0 (Water Pollutants, Chemical); 0 (Xylenes); 0 (sulfate radical); 059QF0KO0R (Water); 3FPU23BG52 (Toluene); J64922108F (Benzene); L5I45M5G0O (ethylbenzene)


  4 / 7303 MEDLINE  
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PMID:29303694
Author:Bae SS; Jung J; Chung D; Baek K
Address:National Marine Biodiversity Institute of Korea, Chungchungnam-do, 33662, Republic of Korea.
Title:Marinobacterium aestuarii sp. nov., a benzene-degrading marine bacterium isolated from estuary sediment.
Source:Int J Syst Evol Microbiol; 68(2):651-656, 2018 Feb.
ISSN:1466-5034
Country of publication:England
Language:eng
Abstract:A Gram-stain-negative, aerobic, motile, flagellated rod-shaped bacterium, designated ST58-10 , was isolated from an estuarine sediment in the Republic of Korea. The strain was able to degrade benzene. Growth of strain ST58-10 was observed at 4-35 °C (optimum, 20-25 °C), pH 5-9 (optimum, pH 7-8) and 1-8 % NaCl (optimum, 3 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain ST58-10 formed a phyletic lineage within the genus Marinobacterium of the family Oceanospirillaceae. Strain ST58-10 was most closely related to Marinobacterium profundum PAMC 27536 (99.6 %) and Marinobacterium rhizophilum CL-YJ9 (98.3 %), and to other members of the genus Marinobacterium(94.5-91.5 %). However, the mean value estimated by using the Genome-to-Genome Distance Calculator was 50.6±7.4 % with M. profundum PAMC 27536 and 30.9±2.8 with M. rhizophilum CL-YJ9 , respectively. An average nucleotide identity value was 89.0 % with M. profundum PAMC 27536 and 85.6 % with M. rhizophilum CL-YJ9 , respectively. The major fatty acids of strain ST58-10 were summed feature 3 (comprising C16 : 1ω7c/C16 : 1ω6c), summed feature 8 (comprising C18 : 1 ω7c/C18 : 1ω6c), C16 : 0 and C10 : 0 3-OH, and contained ubiquinone (Q-8) as the sole isoprenoid quinone. Phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminolipids, an unidentified glycolipid and an unidentified lipid were detected as polar lipids. The DNA G+C content of strain ST58-10 was 58.78 mol%. On the basis of the phenotypic, chemotaxonomic and molecular properties, strain ST58-10 represents a novel species of the genus Marinobacterium, for which the name Marinobacterium aestuarii sp. nov. is proposed. The type strain is ST58-10 (=KCTC 52193 =NBRC 112103 ).
Publication type:JOURNAL ARTICLE
Name of substance:0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S); 1339-63-5 (Ubiquinone); CQA993F7P8 (ubiquinone 8); J64922108F (Benzene)


  5 / 7303 MEDLINE  
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PMID:29235601
Author:Mandal P; Kundu BK; Vyas K; Sabu V; Helen A; Dhankhar SS; Nagaraja CM; Bhattacherjee D; Bhabak KP; Mukhopadhyay S
Address:Department of Chemistry, School of Basic Sciences, Indian Institute of Technology Indore, Indore 453552, India. suman@iiti.ac.in.
Title:Ruthenium(ii) arene NSAID complexes: inhibition of cyclooxygenase and antiproliferative activity against cancer cell lines.
Source:Dalton Trans; 47(2):517-527, 2018 Jan 02.
ISSN:1477-9234
Country of publication:England
Language:eng
Abstract:Non-steroidal anti-inflammatory drugs (NSAIDs) are a group of molecules which have been found to be active against cancer cells with chemopreventive properties by targeting cyclooxygenase (COX-1 and COX-2) and lipoxygenase (LOX), commonly upregulated (particularly COX-2) in malignant tumors. Arene ruthenium(ii) complexes with a pseudo-octahedral coordination environment containing different ancillary ligands have shown remarkable activity against primary and metastatic tumors as reported earlier. This work describes the synthesis of four novel ruthenium(ii)-arene complexes viz. [Ru(η -p-cymene)(nap)Cl] 1 [Hnap = naproxen or (S)-2-(6-methoxy-2-naphthyl)propionic acid], [Ru(η -p-cymene)(diclo)Cl] 2 [Hdiclo = diclofenac or 2-[(2,6-dichlorophenyl)amino] benzeneacetic acid, [Ru(η -p-cymene)(ibu)Cl] 3 [Hibu = ibuprofen or 2-(4-isobutylphenyl)propanoic acid] and [Ru(η -p-cymene)(asp)Cl] 4 [Hasp = aspirin or 2-acetoxy benzoic acid] using different NSAIDs as chelating ligands. Complexes 1-3 have shown promising antiproliferative activity against three different cell lines with GI (concentration of drug causing 50% inhibition of cell growth) values comparable to adriamycin. At the concentration of 50 µM, complex 3 is more effective in the inhibition of cyclooxygenase and lipooxygenase enzymes, followed by complex 2 and complex 1 in comparison to their respective free NSAID ligands indicating a possible correlation between the inhibition of COX and/or LOX and anticancer properties. Molecular docking studies with COX-2 reveal that complexes 1 and 2 having naproxen and diclofenac ligands exhibit stronger interactions with COX-2 than their respective free NSAIDs and these results are in good agreement with their relative experimentally observed COX inhibition as well as anti-proliferative activities.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Anti-Inflammatory Agents, Non-Steroidal); 0 (Cyclooxygenase Inhibitors); 0 (Lipoxygenase Inhibitors); 0 (Organometallic Compounds); 27432CM55Q (Serum Albumin, Bovine); 7UI0TKC3U5 (Ruthenium); 9007-49-2 (DNA); EC 1.13.11.12 (Lipoxygenase); EC 1.14.99.1 (Cyclooxygenase 1); EC 1.14.99.1 (Cyclooxygenase 2); EC 1.14.99.1 (Prostaglandin-Endoperoxide Synthases); J64922108F (Benzene); YOW8V9698H (Dimethyl Sulfoxide)


  6 / 7303 MEDLINE  
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PMID:28941718
Author:Healy RM; Chen Q; Bennett J; Karellas NS
Address:Environmental Monitoring and Reporting Branch, Ontario Ministry of the Environment and Climate Change, 125 Resources Rd, Toronto, Ontario M9P 3V6, Canada. Electronic address: robert.healy@ontario.ca.
Title:A multi-year study of VOC emissions at a chemical waste disposal facility using mobile APCI-MS and LPCI-MS instruments.
Source:Environ Pollut; 232:220-228, 2018 Jan.
ISSN:1873-6424
Country of publication:England
Language:eng
Abstract:Real-time analysis of volatile organic compounds (VOCs) in air is useful both for source identification and emissions compliance applications. In this work, two complementary triple quadrupole mass spectrometers, fitted with an atmospheric pressure chemical ionization (APCI) and a low pressure chemical ionization (LPCI) source, respectively, were deployed simultaneously to investigate emissions of VOCs associated with an Ontario-based chemical waste disposal facility. Mobile measurements performed upwind and downwind of the facility enabled selection of the best locations for stationary sampling. Seven separate field studies were undertaken between 2000 and 2016 to assess how emissions of VOCs have changed at the site as a function of time. Up to twenty-nine VOCs were successfully identified and quantified using MS/MS in each study. Simultaneous deployment of the two mass spectrometers enabled the detection of polar VOCs including alcohols, esters, amines and ketones as well as non-polar aromatic VOCs including benzene and naphthalene in real time. Concentrations of VOCs were found to decrease significantly in the vicinity of the facility over the sixteen year period, in particular since 2007. Concentration values for each year are compared with odour thresholds and provincial guidelines and implications of future expansion of on-site solid waste landfill volumes are also discussed.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Air Pollutants); 0 (Volatile Organic Compounds); J64922108F (Benzene)


  7 / 7303 MEDLINE  
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PMID:29191894
Author:Mulvey RE
Address:WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK. r.e.mulvey@strath.ac.uk.
Title:Benzene submits to main-group power.
Source:Science; 358(6367):1132, 2017 12 01.
ISSN:1095-9203
Country of publication:United States
Language:eng
Publication type:JOURNAL ARTICLE; COMMENT
Name of substance:J64922108F (Benzene)


  8 / 7303 MEDLINE  
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PMID:28886060
Author:Abplanalp W; DeJarnett N; Riggs DW; Conklin DJ; McCracken JP; Srivastava S; Xie Z; Rai S; Bhatnagar A; O'Toole TE
Address:Diabetes and Obesity Center, University of Louisville, Louisville, Kentucky, United States of America.
Title:Benzene exposure is associated with cardiovascular disease risk.
Source:PLoS One; 12(9):e0183602, 2017.
ISSN:1932-6203
Country of publication:United States
Language:eng
Abstract:Benzene is a ubiquitous, volatile pollutant present at high concentrations in toxins (e.g. tobacco smoke) known to increase cardiovascular disease (CVD) risk. Despite its prevalence, the cardiovascular effects of benzene have rarely been studied. Hence, we examined whether exposure to benzene is associated with increased CVD risk. The effects of benzene exposure in mice were assessed by direct inhalation, while the effects of benzene exposure in humans was assessed in 210 individuals with mild to high CVD risk by measuring urinary levels of the benzene metabolite trans,trans-muconic acid (t,t-MA). Generalized linear models were used to assess the association between benzene exposure and CVD risk. Mice inhaling volatile benzene had significantly reduced levels of circulating angiogenic cells (Flk-1+/Sca-1+) as well as an increased levels of plasma low-density lipoprotein (LDL) compared with control mice breathing filtered air. In the human cohort, urinary levels of t,t-MA were inversely associated several populations of circulating angiogenic cells (CD31+/34+/45+, CD31+/34+/45+/AC133-, CD34+/45+/AC133+). Although t,t-MA was not associated with plasma markers of inflammation or thrombosis, t,t-MA levels were higher in smokers and in individuals with dyslipidemia. In smokers, t,t-MA levels were positively associated with urinary metabolites of nicotine (cotinine) and acrolein (3-hydroxymercapturic acid). Levels of t,t-MA were also associated with CVD risk as assessed using the Framingham Risk Score and this association was independent of smoking. Thus, benzene exposure is associated with increased CVD risk and deficits in circulating angiogenic cells in both smokers and non-smokers.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Lipoproteins, HDL); 0 (Lipoproteins, LDL); 3KD92ZL2KH (muconic acid); J64922108F (Benzene); K5161X06LL (Cotinine); X045WJ989B (Sorbic Acid)


  9 / 7303 MEDLINE  
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PMID:28873471
Author:Rasse DP; Budai A; O'Toole A; Ma X; Rumpel C; Abiven S
Address:Department of Soil Quality and Climate Change, Norwegian Institute of Bioeconomy Research, Ås, Norway.
Title:Persistence in soil of Miscanthus biochar in laboratory and field conditions.
Source:PLoS One; 12(9):e0184383, 2017.
ISSN:1932-6203
Country of publication:United States
Language:eng
Abstract:Evaluating biochars for their persistence in soil under field conditions is an important step towards their implementation for carbon sequestration. Current evaluations might be biased because the vast majority of studies are short-term laboratory incubations of biochars produced in laboratory-scale pyrolyzers. Here our objective was to investigate the stability of a biochar produced with a medium-scale pyrolyzer, first through laboratory characterization and stability tests and then through field experiment. We also aimed at relating properties of this medium-scale biochar to that of a laboratory-made biochar with the same feedstock. Biochars were made of Miscanthus biomass for isotopic C-tracing purposes and produced at temperatures between 600 and 700°C. The aromaticity and degree of condensation of aromatic rings of the medium-scale biochar was high, as was its resistance to chemical oxidation. In a 90-day laboratory incubation, cumulative mineralization was 0.1% for the medium-scale biochar vs. 45% for the Miscanthus feedstock, pointing to the absence of labile C pool in the biochar. These stability results were very close to those obtained for biochar produced at laboratory-scale, suggesting that upscaling from laboratory to medium-scale pyrolyzers had little effect on biochar stability. In the field, the medium-scale biochar applied at up to 25 t C ha-1 decomposed at an estimated 0.8% per year. In conclusion, our biochar scored high on stability indices in the laboratory and displayed a mean residence time > 100 years in the field, which is the threshold for permanent removal in C sequestration projects.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Biomarkers); 0 (Carboxylic Acids); 0 (Organic Chemicals); 0 (Soil); 0 (biochar); 142M471B3J (Carbon Dioxide); 16291-96-6 (Charcoal); 7440-44-0 (Carbon); J64922108F (Benzene)


  10 / 7303 MEDLINE  
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Silveira, Josianne Nicácio
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PMID:28863335
Author:Mendes MPR; Silveira JN; Andre LC
Address:Department of Clinical and Toxicological Analysis, Faculty of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, Brazil. Electronic address: micheleprm@yahoo.com.br.
Title:An efficient analytical method for determination of S-phenylmercapturic acid in urine by HPLC fluorimetric detector to assessing benzene exposure.
Source:J Chromatogr B Analyt Technol Biomed Life Sci; 1063:136-140, 2017 Sep 15.
ISSN:1873-376X
Country of publication:Netherlands
Language:eng
Abstract:Benzene is an important occupational and environmental contaminant, naturally present in petroleum and as by-product in the steel industry. Toxicological studies showed pronounced myelotoxic action, causing leukemic and others blood cells disorders. Assessing of benzene exposure is performed by biomarkers as trans, trans-muconic acid (AttM) and S-phenylmercapturic acid (S-PMA) in urine. Due to specificity of S-PMA, this biomarker has been proposed to asses lower levels of benzene in air. The aim of this study was to validate an analytical method for the quantification of S-PMA by High-Performance Liquid Chromatography with fluorometric detector. The development of an analytical method of S-PMA in urine was carried out by solid phase extraction (SPE) using C-18 phase. The eluated were submitted to water bath at 75°C and nitrogen to analyte concentration, followed by alkaline hydrolysis and derivatization with monobromobimane. The chromatography conditions were reverse phase C-18 column (240mm, 4mm and 5µm) at 35°C; acetonitrile and 0.5% acetic acid (50:50) as mobile phase with a flow of 0.8mL/min. The limits of detection and quantification were 0.22µg/L and 0.68µg/L, respectively. The linearity was verified by simple linear regression, and the method exhibited good linearity in the range of 10-100µg/L. There was no matrix effect for S-PMA using concentrations of 40, 60, 80 and 100µg/L. The intra- and interassay precision showed coefficient of variation of less than 10% and the recovery ranged from 83.4 to 102.8% with an average of 94.4%. The stability of S-PMA in urine stored at -20°C was of seven weeks. The conclusion is that this method presents satisfactory results per their figures of merit. This proposed method for determining urinary S-PMA showed adequate sensitivity for assessment of occupational and environmental exposure to benzene using S-PMA as biomarker of exposure.
Publication type:JOURNAL ARTICLE
Name of substance:4775-80-8 (S-phenyl-N-acetylcysteine); J64922108F (Benzene); WYQ7N0BPYC (Acetylcysteine)



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