Base de dados : MEDLINE
Pesquisa : D02.033.755.600 [Categoria DeCS]
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[PMID]:29223046
[Au] Autor:Charisiadis P; Makris KC
[Ad] Endereço:Cyprus International Institute for Environmental and Public Health, Cyprus University of Technology, Limassol, Cyprus.
[Ti] Título:Cohort-friendly protocol for a sensitive and fast method for trihalomethanes in urine using gas chromatography-Triple quadrupole mass spectrometry.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1072:336-340, 2018 Jan 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A cohort-friendly biomonitoring protocol has been developed for measuring biomarkers of exposure to disinfection by-products (trihalomethanes, THM) in urine using small initial volume (3mL) and short analysis time (∼10min) that facilitates the throughput of a large number of samples. The objective of this study was to optimise a cohort-friendly biomonitoring protocol for the determination of four THM analytes in human urine using gas chromatography coupled with triple quadrupole mass spectrometry (GC-QqQ-MS/MS). The proposed methodology will facilitate the inclusion of such urinary THM measurements into large population health studies.
[Mh] Termos MeSH primário: Cromatografia Gasosa-Espectrometria de Massas/métodos
Espectrometria de Massas em Tandem/métodos
Trialometanos/urina
[Mh] Termos MeSH secundário: 1-Propanol
Acetona
Seres Humanos
Limite de Detecção
Modelos Lineares
Reprodutibilidade dos Testes
Trialometanos/química
Trialometanos/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Trihalomethanes); 1364PS73AF (Acetone); 96F264O9SV (1-Propanol)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171210
[St] Status:MEDLINE


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[PMID]:28760847
[Au] Autor:Xu Z; Wang M; Ye BC
[Ad] Endereço:Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.
[Ti] Título:TetR Family Transcriptional Regulator PccD Negatively Controls Propionyl Coenzyme A Assimilation in Saccharopolyspora erythraea.
[So] Source:J Bacteriol;199(20), 2017 Oct 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Propanol stimulates erythromycin biosynthesis by increasing the supply of propionyl coenzyme A (propionyl-CoA), a starter unit of erythromycin production in Propionyl-CoA is assimilated via propionyl-CoA carboxylase to methylmalonyl-CoA, an extender unit of erythromycin. We found that the addition of -propanol or propionate caused a 4- to 16-fold increase in the transcriptional levels of the SACE_3398-3400 locus encoding propionyl-CoA carboxylase, a key enzyme in propionate metabolism. The regulator PccD was proved to be directly involved in the transcription regulation of the SACE_3398-3400 locus by EMSA and DNase I footprint analysis. The transcriptional levels of SACE_3398-3400 were upregulated 15- to 37-fold in the gene deletion strain (Δ ) and downregulated 3-fold in the overexpression strain (WT/pIB- ), indicating that PccD was a negative transcriptional regulator of SACE_3398-3400. The Δ strain has a higher growth rate than that of the wild-type strain (WT) on Evans medium with propionate as the sole carbon source, whereas the growth of the WT/pIB- strain was repressed. As a possible metabolite of propionate metabolism, methylmalonic acid was identified as an effector molecule of PccD and repressed its regulatory activity. A higher level of erythromycin in the Δ strain was observed compared with that in the wild-type strain. Our study reveals a regulatory mechanism in propionate metabolism and suggests new possibilities for designing metabolic engineering to increase erythromycin yield. Our work has identified the novel regulator PccD that controls the expression of the gene for propionyl-CoA carboxylase, a key enzyme in propionyl-CoA assimilation in PccD represses the generation of methylmalonyl-CoA through carboxylation of propionyl-CoA and reveals an effect on biosynthesis of erythromycin. This finding provides novel insight into propionyl-CoA assimilation, and extends our understanding of the regulatory mechanisms underlying the biosynthesis of erythromycin.
[Mh] Termos MeSH primário: Acil Coenzima A/biossíntese
Proteínas de Bactérias/metabolismo
Regulação Bacteriana da Expressão Gênica
Proteínas Repressoras/metabolismo
Saccharopolyspora/genética
[Mh] Termos MeSH secundário: 1-Propanol/metabolismo
Proteínas de Bactérias/genética
Pegada de DNA
DNA Bacteriano/metabolismo
Ensaio de Desvio de Mobilidade Eletroforética
Deleção de Genes
Expressão Gênica
Perfilação da Expressão Gênica
Propionatos/metabolismo
Ligação Proteica
Proteínas Repressoras/genética
Saccharopolyspora/metabolismo
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acyl Coenzyme A); 0 (Bacterial Proteins); 0 (DNA, Bacterial); 0 (Propionates); 0 (Repressor Proteins); 317-66-8 (propionyl-coenzyme A); 96F264O9SV (1-Propanol)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171015
[Lr] Data última revisão:
171015
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170802
[St] Status:MEDLINE


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[PMID]:28542503
[Au] Autor:Létoffé S; Chalabaev S; Dugay J; Stressmann F; Audrain B; Portais JC; Letisse F; Ghigo JM
[Ad] Endereço:Institut Pasteur, Genetics of Biofilms Laboratory. 25-28 rue du Docteur Roux, France.
[Ti] Título:Biofilm microenvironment induces a widespread adaptive amino-acid fermentation pathway conferring strong fitness advantage in Escherichia coli.
[So] Source:PLoS Genet;13(5):e1006800, 2017 May.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial metabolism has been studied primarily in liquid cultures, and exploration of other natural growth conditions may reveal new aspects of bacterial biology. Here, we investigate metabolic changes occurring when Escherichia coli grows as surface-attached biofilms, a common but still poorly characterized bacterial lifestyle. We show that E. coli adapts to hypoxic conditions prevailing within biofilms by reducing the amino acid threonine into 1-propanol, an important industrial commodity not known to be naturally produced by Enterobacteriaceae. We demonstrate that threonine degradation corresponds to a fermentation process maintaining cellular redox balance, which confers a strong fitness advantage during anaerobic and biofilm growth but not in aerobic conditions. Whereas our study identifies a fermentation pathway known in Clostridia but previously undocumented in Enterobacteriaceae, it also provides novel insight into how growth in anaerobic biofilm microenvironments can trigger adaptive metabolic pathways edging out competition with in mixed bacterial communities.
[Mh] Termos MeSH primário: Adaptação Fisiológica
Biofilmes
Escherichia coli/metabolismo
Fermentação
Treonina/metabolismo
[Mh] Termos MeSH secundário: 1-Propanol/metabolismo
Escherichia coli/crescimento & desenvolvimento
Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
2ZD004190S (Threonine); 96F264O9SV (1-Propanol); S88TT14065 (Oxygen)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170615
[Lr] Data última revisão:
170615
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006800


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[PMID]:28433208
[Au] Autor:Verardo E; Atteia O; Prommer H
[Ad] Endereço:ENSEGID, EA4592 G&E, 1 allée Daguin, 33607, Pessac, France. Electronic address: elicia.verardo@ipb.fr.
[Ti] Título:Elucidating the fate of a mixed toluene, DHM, methanol, and i-propanol plume during in situ bioremediation.
[So] Source:J Contam Hydrol;201:6-18, 2017 Jun.
[Is] ISSN:1873-6009
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Organic pollutants such as solvents or petroleum products are widespread contaminants in soil and groundwater systems. In-situ bioremediation is a commonly used remediation technology to clean up the subsurface to eliminate the risks of toxic substances to reach potential receptors in surface waters or drinking water wells. This study discusses the development of a subsurface model to analyse the performance of an actively operating field-scale enhanced bioremediation scheme. The study site was affected by a mixed toluene, dihydromyrcenol (DHM), methanol, and i-propanol plume. A high-resolution, time-series of data was used to constrain the model development and calibration. The analysis shows that the observed failure of the treatment system is linked to an inefficient oxygen injection pattern. Moreover, the model simulations also suggest that additional contaminant spillages have occurred in 2012. Those additional spillages and their associated additional oxygen demand resulted in a significant increase in contaminant fluxes that remained untreated. The study emphasises the important role that reactive transport modelling can play in data analyses and for enhancing remediation efficiency.
[Mh] Termos MeSH primário: 1-Propanol/análise
Metanol/análise
Monoterpenos/análise
Octanóis/análise
Tolueno/análise
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Biodegradação Ambiental
França
Água Subterrânea/química
Modelos Teóricos
Petróleo
Solo/química
Poluentes do Solo/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Monoterpenes); 0 (Octanols); 0 (Petroleum); 0 (Soil); 0 (Soil Pollutants); 0 (Water Pollutants, Chemical); 3FPU23BG52 (Toluene); 46L1B02ND9 (dihydromyrcenol); 96F264O9SV (1-Propanol); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170424
[St] Status:MEDLINE


  5 / 2673 MEDLINE  
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[PMID]:28320283
[Au] Autor:Ashraf R; Rashid N; Basheer S; Aziz I; Akhtar M
[Ad] Endereço:School of Biological Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan. naeem.ff.sbs@pu.edu.pk.
[Ti] Título:Glutathione-Dependent Formaldehyde Dehydrogenase Homolog from Bacillus subtilis Strain R5 is a Propanol-Preferring Alcohol Dehydrogenase.
[So] Source:Biochemistry (Mosc);82(1):13-23, 2017 Jan.
[Is] ISSN:1608-3040
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Genome search of Bacillus subtilis revealed the presence of an open reading frame annotated as glutathione-dependent formaldehyde dehydrogenase/alcohol dehydrogenase. The open reading frame consists of 1137 nucleotides corresponding to a polypeptide of 378 amino acids. To examine whether the encoded protein is glutathione-dependent formaldehyde dehydrogenase or alcohol dehydrogenase, we cloned and characterized the gene product. Enzyme activity assays revealed that the enzyme exhibits a metal ion-dependent alcohol dehydrogenase activity but no glutathione-dependent formaldehyde dehydrogenase or aldehyde dismutase activity. Although the protein is of mesophilic origin, optimal temperature for the enzyme activity is 60°C. Thermostability analysis by circular dichroism spectroscopy revealed that the protein is stable up to 60°C. Presence or absence of metal ions in the reaction mixture did not affect the enzyme activity. However, metal ions were necessary at the time of protein production and folding. There was a marked difference in the enzyme activity and CD spectra of the proteins produced in the presence and absence of metal ions. The experimental results obtained in this study demonstrate that the enzyme is a bona-fide alcohol dehydrogenase and not a glutathione-dependent formaldehyde dehydrogenase.
[Mh] Termos MeSH primário: 1-Propanol/química
Aldeído Oxirredutases/química
Bacillus subtilis/enzimologia
Proteínas de Bactérias/genética
[Mh] Termos MeSH secundário: Aldeído Oxirredutases/genética
Bacillus subtilis/genética
Proteínas de Bactérias/química
Estabilidade Enzimática
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 96F264O9SV (1-Propanol); EC 1.1.1.284 (formaldehyde dehydrogenase (glutathione)); EC 1.2.- (Aldehyde Oxidoreductases)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170322
[Lr] Data última revisão:
170322
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170322
[St] Status:MEDLINE
[do] DOI:10.1134/S0006297917010023


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[PMID]:27965715
[Au] Autor:Cafarelli A; Miloro P; Verbeni A; Carbone M; Menciassi A
[Ad] Endereço:The BioRobotics Institute, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggio 34, 56025 Pontedera, Pisa, Italy.
[Ti] Título:Speed of sound in rubber-based materials for ultrasonic phantoms.
[So] Source:J Ultrasound;19(4):251-256, 2016 Dec.
[Is] ISSN:1876-7931
[Cp] País de publicação:Italy
[La] Idioma:eng
[Ab] Resumo:PURPOSE: In this work we provide measurements of speed of sound ( ) and acoustic impedance ( ) of some doped/non-doped rubber-based materials dedicated to the development of ultrasound phantoms. These data are expected to be useful for speeding-up the preparation of multi-organ phantoms which show similar echogenicity to real tissues. METHODS: Different silicones (Ecoflex, Dragon-Skin Medium) and polyurethane rubbers with different liquid (glycerol, commercial detergent, -propanol) and solid (aluminum oxide, graphene, steel, silicon powder) inclusions were prepared. of materials under investigation was measured in an experimental setup and was obtained by multiplying the density and the of each material. Finally, an anatomically realistic liver phantom has been fabricated selecting some of the tested materials. RESULTS: and evaluation for different rubber materials and formulations are reported. The presence of liquid additives appears to increase the , while solid inclusions generally reduce the . The ultrasound images of realized custom fabricated heterogeneous liver phantom and a real liver show remarkable similarities. CONCLUSIONS: The development of new materials' formulations and the knowledge of acoustic properties, such as speed of sound and acoustic impedance, could improve and speed-up the development of phantoms for simulations of ultrasound medical procedures.
[Mh] Termos MeSH primário: Imagens de Fantasmas
Borracha
Silicones
Som
Ultrassonografia/instrumentação
[Mh] Termos MeSH secundário: 1-Propanol
Óxido de Alumínio
Detergentes
Desenho de Equipamento
Glicerol
Grafite
Seres Humanos
Fígado/diagnóstico por imagem
Modelos Biológicos
Poliuretanos
Silício
Aço
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Detergents); 0 (Polyurethanes); 0 (Silicones); 12597-69-2 (Steel); 7782-42-5 (Graphite); 9006-04-6 (Rubber); 96F264O9SV (1-Propanol); LMI26O6933 (Aluminum Oxide); PDC6A3C0OX (Glycerol); Z4152N8IUI (Silicon)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170224
[Lr] Data última revisão:
170224
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161215
[St] Status:MEDLINE


  7 / 2673 MEDLINE  
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[PMID]:27498831
[Au] Autor:Di Giulio M; Genovese S; Fiorito S; Epifano F; Nostro A; Cellini L
[Ad] Endereço:a Department of Pharmacy , University "G. d'Annunzio" Chieti-Pescara , Chieti , Italy.
[Ti] Título:Antimicrobial evaluation of selected naturally occurring oxyprenylated secondary metabolites.
[So] Source:Nat Prod Res;30(16):1870-4, 2016 Aug.
[Is] ISSN:1478-6427
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study tested the antimicrobial activity of eight selected naturally occurring oxyprenylated secondary metabolites against Staphylococcus aureus ATCC 29213, S. epidermidis ATCC 35984, Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 9027 and Candida albicans ATCC 10231. Results showed a moderate antimicrobial activity. The most active compounds were 3-(4-geranyloxyphenyl)-1-ethanol (4) and 3-(4-isopentenyloxyphenyl)-1-propanol (5) that were tested on mature and in-formation biofilms of all micro-organisms, moreover the cytotoxic activity was evaluated. Except for S. epidermidis, both compounds reduced significantly (p < 0.05) the microbial biofilm formation at 1/2 MIC and 1/4 MIC, in particular, compounds 4 and 5 at each concentration, inhibited E. coli biofilm formation to a greater extent, the biofilm formation was never more than 44% in respect to the control, moreover both compounds showed a low cytotoxic effect. Oxyprenylated derivatives may be of great interest for the development of novel antimicrobial therapeutic strategies and the synthesis of semi-synthetic analogues with anti-biofilm efficacy.
[Mh] Termos MeSH primário: Anti-Infecciosos/farmacologia
Avaliação Pré-Clínica de Medicamentos/métodos
Metabolismo Secundário
[Mh] Termos MeSH secundário: 1-Propanol/química
1-Propanol/farmacologia
Antibacterianos/farmacologia
Anti-Infecciosos/química
Biofilmes/efeitos dos fármacos
Candida albicans/efeitos dos fármacos
Escherichia coli/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Pseudomonas aeruginosa/efeitos dos fármacos
Pseudomonas aeruginosa/fisiologia
Staphylococcus aureus/efeitos dos fármacos
Staphylococcus aureus/fisiologia
Staphylococcus epidermidis/efeitos dos fármacos
Staphylococcus epidermidis/fisiologia
Terpenos/química
Terpenos/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Anti-Infective Agents); 0 (Terpenes); 96F264O9SV (1-Propanol)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160809
[St] Status:MEDLINE
[do] DOI:10.1080/14786419.2015.1079908


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[PMID]:27497899
[Au] Autor:Weiss K; Kroschewski B; Auerbach H
[Ad] Endereço:Humboldt Universität zu Berlin, Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences, D-10115 Berlin, Germany. Electronic address: kirsten.weiss@agrar.hu-berlin.de.
[Ti] Título:Effects of air exposure, temperature and additives on fermentation characteristics, yeast count, aerobic stability and volatile organic compounds in corn silage.
[So] Source:J Dairy Sci;99(10):8053-8069, 2016 Oct.
[Is] ISSN:1525-3198
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Ensiling conditions strongly influence fermentation characteristics, yeast count, and aerobic stability. Numerous volatile organic compounds including esters are produced, which may negatively affect feed intake and animal performance and air quality. In addition to a farm survey, 3 laboratory experiments were carried out to study the effects of air (by delayed sealing or by air infiltration during anaerobic storage), temperature (20 and 35°C), and various types of additives [blends of either sodium benzoate and sodium propionate (SBSP) or of sodium benzoate and potassium sorbate (SBPS); buffered mixture of formic and propionic acids (FAPA); homofermentative inoculant (LAB)]. After additive treatment, chopped whole corn plants were packed into 1.5-L glass jars and stored for several months. For treatments with air infiltration, glass jars with holes in the lid and body were used. The farm survey in 2009 revealed large variation in lactate, acetate, ethanol, n-propanol, and 1,2-propanediol concentrations. Whereas ethyl esters were detected in all silages, the mean ethyl lactate concentrations were higher than those for ethyl acetate (474 vs. 38mg/kg of dry matter). In the ensiling experiments, few unequivocal effects of the tested factors on the analyzed parameters were observed due to many interactions. Delayed ensiling without additives decreased lactic acid production but, in one trial, increased acetic acid and had no effect on ethanol. The effect of delayed sealing on yeast counts and aerobic stability differed widely among experiments. Air infiltration during fermentation tested in one trial did not alter lactic acid production, but resulted in more acetic acid in delayed and more ethanol than in promptly sealed untreated silages. Greater ethanol production was associated with increased yeast numbers. Storage at high temperature resulted in lower lactic acid and n-propanol, and a trend toward reduced ethanol production was observed. The additive FAPA consistently caused increased ethanol and reduced n-propanol levels with no effect on yeast counts and aerobic stability. When the additives SBSP and SBPS decreased n-propanol and ethanol, reduced yeast counts were also found. Ethyl ester formation was strongly correlated with those of ethanol and to a lesser degree with those of the respective acid.
[Mh] Termos MeSH primário: Ração Animal/análise
Silagem/análise
Compostos Orgânicos Voláteis/análise
Leveduras/metabolismo
Zea mays/química
[Mh] Termos MeSH secundário: 1-Propanol/análise
Acetatos/análise
Ração Animal/microbiologia
Animais
Bovinos
Dieta/veterinária
Etanol/análise
Fermentação
Concentração de Íons de Hidrogênio
Ácido Láctico/análise
Modelos Lineares
Propionatos/análise
Propilenoglicol/análise
Silagem/microbiologia
Benzoato de Sódio/análise
Ácido Sórbico/análise
Temperatura Ambiente
Zea mays/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetates); 0 (Propionates); 0 (Volatile Organic Compounds); 33X04XA5AT (Lactic Acid); 3K9958V90M (Ethanol); 6DC9Q167V3 (Propylene Glycol); 96F264O9SV (1-Propanol); DK6Y9P42IN (sodium propionate); OJ245FE5EU (Sodium Benzoate); X045WJ989B (Sorbic Acid)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160808
[St] Status:MEDLINE


  9 / 2673 MEDLINE  
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[PMID]:27488829
[Au] Autor:Chun HJ; Poklis JL; Poklis A; Wolf CE
[Ad] Endereço:Department of Forensic Science, Virginia Commonwealth University, Richmond, VA 23284, USA.
[Ti] Título:Development and Validation of a Method for Alcohol Analysis in Brain Tissue by Headspace Gas Chromatography with Flame Ionization Detector.
[So] Source:J Anal Toxicol;40(8):653-658, 2016 Oct.
[Is] ISSN:1945-2403
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Ethanol is the most widely used and abused drug. While blood is the preferred specimen for analysis, tissue specimens such as brain serve as alternative specimens for alcohol analysis in post-mortem cases where blood is unavailable or contaminated. A method was developed using headspace gas chromatography with flame ionization detection (HS-GC-FID) for the detection and quantification of ethanol, acetone, isopropanol, methanol and n-propanol in brain tissue specimens. Unfixed volatile-free brain tissue specimens were obtained from the Department of Pathology at Virginia Commonwealth University. Calibrators and controls were prepared from 4-fold diluted homogenates of these brain tissue specimens, and were analyzed using t-butanol as the internal standard. The chromatographic separation was performed with a Restek BAC2 column. A linear calibration was generated for all analytes (mean r > 0.9992) with the limits of detection and quantification of 100-110 mg/kg. Matrix effect from the brain tissue was determined by comparing the slopes of matrix prepared calibration curves with those of aqueous calibration curves; no significant differences were observed for ethanol, acetone, isopropanol, methanol and n-propanol. The bias and the CVs for all volatile controls were ≤10%. The method was also evaluated for carryover, selectivity, interferences, bench-top stability and freeze-thaw stability. The HS-GC-FID method was determined to be reliable and robust for the analysis of ethanol, acetone, isopropanol, methanol and n-propanol concentrations in brain tissue, effectively expanding the specimen options for post-mortem alcohol analysis.
[Mh] Termos MeSH primário: Intoxicação Alcoólica/diagnóstico
Química Encefálica
Cromatografia Gasosa
Etanol/análise
Ionização de Chama
[Mh] Termos MeSH secundário: 1-Propanol/análise
2-Propanol/análise
Acetona/análise
Calibragem
Diagnóstico
Seres Humanos
Limite de Detecção
Modelos Lineares
Metanol/análise
Reprodutibilidade dos Testes
Manejo de Espécimes
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
1364PS73AF (Acetone); 3K9958V90M (Ethanol); 96F264O9SV (1-Propanol); ND2M416302 (2-Propanol); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171001
[Lr] Data última revisão:
171001
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160805
[St] Status:MEDLINE


  10 / 2673 MEDLINE  
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[PMID]:27351338
[Au] Autor:Lopes JL; Yoneda JS; Martins JM; DeMarco R; Jameson DM; Castro AM; Bossolan NR; Wallace BA; Araujo AP
[Ad] Endereço:Instituto de Física, Universidade de São Paulo, São Paulo, Brazil.
[Ti] Título:Environmental Factors Modulating the Stability and Enzymatic Activity of the Petrotoga mobilis Esterase (PmEst).
[So] Source:PLoS One;11(6):e0158146, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Enzymes isolated from thermophilic organisms found in oil reservoirs can find applications in many fields, including the oleochemical, pharmaceutical, bioenergy, and food/dairy industries. In this study, in silico identification and recombinant production of an esterase from the extremophile bacteria Petrotoga mobilis (designated PmEst) were performed. Then biochemical, bioinformatics and structural characterizations were undertaken using a combination of synchrotron radiation circular dichroism (SRCD) and fluorescence spectroscopies to correlate PmEst stability and hydrolytic activity on different substrates. The enzyme presented a high Michaelis-Menten constant (KM 0.16 mM) and optimum activity at ~55°C for p-nitrophenyl butyrate. The secondary structure of PmEst was preserved at acid pH, but not under alkaline conditions. PmEst was unfolded at high concentrations of urea or guanidine through apparently different mechanisms. The esterase activity of PmEst was preserved in the presence of ethanol or propanol and its melting temperature increased ~8°C in the presence of these organic solvents. PmEst is a mesophilic esterase with substrate preference towards short-to medium-length acyl chains. The SRCD data of PmEst is in agreement with the prediction of an α/ß protein, which leads us to assume that it displays a typical fold of esterases from this family. The increased enzyme stability in organic solvents may enable novel applications for its use in synthetic biology. Taken together, our results demonstrate features of the PmEst enzyme that indicate it may be suitable for applications in industrial processes, particularly, when the use of polar organic solvents is required.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Esterases/metabolismo
Células Fotorreceptoras Retinianas Bastonetes/enzimologia
[Mh] Termos MeSH secundário: 1-Propanol/química
Proteínas de Bactérias/química
Estabilidade Enzimática
Esterases/química
Etanol/química
Concentração de Íons de Hidrogênio
Dobramento de Proteína
Especificidade por Substrato
Ureia/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 3K9958V90M (Ethanol); 8W8T17847W (Urea); 96F264O9SV (1-Propanol); EC 3.1.- (Esterases)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160629
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0158146



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