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  1 / 19204 MEDLINE  
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[PMID]:29214538
[Au] Autor:Akbarzade S; Chamsaz M; Rounaghi GH; Ghorbani M
[Ad] Endereço:Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.
[Ti] Título:Zero valent Fe-reduced graphene oxide quantum dots as a novel magnetic dispersive solid phase microextraction sorbent for extraction of organophosphorus pesticides in real water and fruit juice samples prior to analysis by gas chromatography-mass spectrometry.
[So] Source:Anal Bioanal Chem;410(2):429-439, 2018 Jan.
[Is] ISSN:1618-2650
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:A selective and sensitive magnetic dispersive solid-phase microextraction (MDSPME) coupled with gas chromatography-mass spectrometry was developed for extraction and determination of organophosphorus pesticides (Sevin, Fenitrothion, Malathion, Parathion, and Diazinon) in fruit juice and real water samples. Zero valent Fe-reduced graphene oxide quantum dots (rGOQDs@ Fe) as a new and effective sorbent were prepared and applied for extraction of organophosphorus pesticides using MDSPME method. In order to study the performance of this new sorbent, the ability of rGOQDs@ Fe was compared with graphene oxide and magnetic graphene oxide nanocomposite by recovery experiments of the organophosphorus pesticides. Several affecting parameters in the microextraction procedure, including pH of donor phase, donor phase volume, stirring rate, extraction time, and desorption conditions such as the type and volume of solvents and desorption time were thoroughly investigated and optimized. Under the optimal conditions, the method showed a wide linear dynamic range with R-square between 0.9959 and 0.9991. The limit of detections, the intraday and interday relative standard deviations (n = 5) were less than 0.07 ngmL , 4.7, and 8.6%, respectively. The method was successfully applied for extraction and determination of organophosphorus pesticides in real water samples (well, river and tap water) and fruit juice samples (apple and grape juice). The obtained relative recoveries were in the range of 82.9%-113.2% with RSD percentages of less than 5.8% for all the real samples.
[Mh] Termos MeSH primário: Sucos de Frutas e Vegetais/análise
Grafite/química
Compostos Organofosforados/análise
Praguicidas/análise
Microextração em Fase Sólida/métodos
Poluentes Químicos da Água/análise
Água/análise
[Mh] Termos MeSH secundário: Cromatografia Gasosa-Espectrometria de Massas/métodos
Ferro/química
Limite de Detecção
Compostos Organofosforados/isolamento & purificação
Oxirredução
Óxidos/química
Praguicidas/isolamento & purificação
Pontos Quânticos/química
Poluentes Químicos da Água/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (Organophosphorus Compounds); 0 (Oxides); 0 (Pesticides); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); 7782-42-5 (Graphite); E1UOL152H7 (Iron)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171208
[St] Status:MEDLINE
[do] DOI:10.1007/s00216-017-0732-9


  2 / 19204 MEDLINE  
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[PMID]:29175403
[Au] Autor:Liang Y; Liu X; Allen MR
[Ad] Endereço:Oak Ridge Institute for Science and Education Participant at U.S. Environmental Protection Agency, USA.
[Ti] Título:Measuring and modeling surface sorption dynamics of organophosphate flame retardants on impervious surfaces.
[So] Source:Chemosphere;193:754-762, 2018 Feb.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Understanding the sorption mechanisms for organophosphate flame retardants (OPFRs) on impervious surfaces is important to improve our knowledge of the fate and transport of OPFRs in indoor environments. The sorption processes of semivolatile organic compounds (SVOCs) on indoor surfaces are heterogeneous (multilayer sorption) or homogeneous (monolayer sorption). In this study, we adopted simplified Langmuir isotherm and Freundlich isotherm in a dynamic sink model to characterize the sorption dynamics of OPFRs on impervious surfaces such as stainless steel and made comparisons between the two models through a series of empty chamber studies. The tests involve two types of stainless steel chambers (53-L small chambers and 44-mL micro chambers) using tris(2-chloroethyl)phosphate (TCEP) and tris(1-chloro-2-propyl)phosphate (TCPP) as target compounds. Our test results show that the dynamic sink model using Freundlich isotherm can better represent the sorption process in the empty small chamber. Micro chamber test results from this study show that the sink model using both simplified Langmuir isotherm and Freundlich isotherm can well fit the measured gas-phase concentrations of OPFRs. We further applied both models and the parameters obtained to predict the gas phase concentrations of OPFRs in a small chamber with an emission source. Comparisons between model predictions and measurements demonstrate the reliability and applicability of the sorption parameters.
[Mh] Termos MeSH primário: Adsorção
Retardadores de Chama/farmacologia
Modelos Teóricos
Organofosfatos/química
[Mh] Termos MeSH secundário: Organofosfatos/farmacologia
Compostos Organofosforados
Reprodutibilidade dos Testes
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Flame Retardants); 0 (Organophosphates); 0 (Organophosphorus Compounds); 0 (tris(1-chloro-2-propyl)phosphate); 32IVO568B0 (tris(chloroethyl)phosphate)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE


  3 / 19204 MEDLINE  
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[PMID]:28743040
[Au] Autor:Furlong MA; Herring A; Buckley JP; Goldman BD; Daniels JL; Engel LS; Wolff MS; Chen J; Wetmur J; Barr DB; Engel SM
[Ad] Endereço:Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States. Electronic address: mfurlong@email.arizona.edu.
[Ti] Título:Prenatal exposure to organophosphorus pesticides and childhood neurodevelopmental phenotypes.
[So] Source:Environ Res;158:737-747, 2017 10.
[Is] ISSN:1096-0953
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Prenatal exposure to organophosphorus pesticides (OPs) has been associated with different neurodevelopmental outcomes across different cohorts. A phenotypic approach may address some of these differences by incorporating information across scales and accounting for the complex correlational structure of neurodevelopmental outcomes. Additionally, Bayesian hierarchical modeling can account for confounding by collinear co-exposures. We use this framework to examine associations between prenatal exposure to OPs and behavior, executive functioning, and IQ assessed at age 6-9 years in a cohort of 404 mother/infant pairs recruited during pregnancy. We derived phenotypes of neurodevelopment with a factor analysis, and estimated associations between OP metabolites and these phenotypes in Bayesian hierarchical models for exposure mixtures. We report seven factors: 1) Impulsivity and Externalizing, 2) Executive Functioning, 3) Internalizing, 4) Perceptual Reasoning, 5) Adaptability, 6) Processing Speed, and 7) Verbal Intelligence. These, along with the Working Memory Index, were standardized and scaled so that positive values reflected positive attributes and negative values represented adverse outcomes. Standardized dimethylphosphate metabolites were negatively associated with Internalizing factor scores (ß^ - 0.13, 95% CI - 0.26, 0.00) but positively associated with Executive Functioning factor scores (ß^ 0.18, 95% CI 0.04, 0.31). Standardized diethylphosphate metabolites were negatively associated with the Working Memory Index (ß^ - 0.17, 95% CI - 0.33, - 0.03). Associations with factor scores were generally stronger and more precise than associations with individual instrument-specific items. Factor analysis of outcomes may provide some advantages in etiological studies of childhood neurodevelopment by incorporating information across scales to reduce dimensionality and improve precision.
[Mh] Termos MeSH primário: Comportamento Infantil/efeitos dos fármacos
Desenvolvimento Infantil/efeitos dos fármacos
Poluentes Ambientais/toxicidade
Função Executiva/efeitos dos fármacos
Inteligência/efeitos dos fármacos
Compostos Organofosforados/toxicidade
Efeitos Tardios da Exposição Pré-Natal/epidemiologia
[Mh] Termos MeSH secundário: Adolescente
Adulto
Criança
Feminino
Seres Humanos
Testes de Inteligência
Estudos Longitudinais
Masculino
Exposição Materna
Cidade de Nova Iorque/epidemiologia
Praguicidas/toxicidade
Gravidez
Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Environmental Pollutants); 0 (Organophosphorus Compounds); 0 (Pesticides)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:180303
[Lr] Data última revisão:
180303
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE


  4 / 19204 MEDLINE  
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[PMID]:29428024
[Au] Autor:Powell RD; Goodenow DA; Christmas AB; Mckillop IH; Evans SL
[Ti] Título:Effect of Systemic Triphenylphosphonium on Organ Function and Oxidative Stress.
[So] Source:Am Surg;84(1):36-42, 2018 Jan 01.
[Is] ISSN:1555-9823
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Conditions of systemic stress can lead to increased reactive oxygen species production, mitochondrial dysfunction, systemic inflammation, and multiorgan dysfunction. Triphenylphosphonium (TPP+) is a lipophilic cation used to target therapeutics to mitochondria. We sought to determine the effects of TPP+ on mitochondrial integrity. Male rats were anesthetized and TPP+ (5 mg/kg) or vehicle (saline) was administered intravenously 30-minutes after anesthesia initiation and intraperitoneally (20 mg/kg) 60-minutes later. Rats were exsanguinated 2-hours postinjection. Cardiac, pulmonary, hepatic, splenic, and renal tissues were analyzed for inflammation, lipid peroxidation, endogenous antioxidant activity, cytokine expression, and mitochondrial function. In vitro modeling was performed using freshly isolated hepatocytes subjected to 8-hours hypoxia/30-minutes reoxygenation in the absence or presence of TPP+. TPP+ increased lipid peroxidation in the liver, lung, and kidney as well as antioxidant activity in the liver, kidney, and spleen. Conversely, antioxidant activity decreased in the lung with TPP+. In addition, TPP+ altered hepatic inflammatory mediators. In vitro, TPP+ attenuated oxygen consumption and, when combined with hypoxic injury, depolarized mitochondrial membranes in hepatocytes. TPP+ induces systemic responses associated with oxidative stress and worsening pathologies in animals. Caution should be exercised when employing TPP+ for therapeutics.
[Mh] Termos MeSH primário: Anti-Inflamatórios/farmacologia
Fígado/efeitos dos fármacos
Mitocôndrias/efeitos dos fármacos
Compostos Organofosforados/farmacologia
Estresse Oxidativo/efeitos dos fármacos
Estresse Psicológico/complicações
[Mh] Termos MeSH secundário: Animais
Seres Humanos
Técnicas In Vitro
Inflamação/tratamento farmacológico
Inflamação/etiologia
Masculino
Ratos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Inflammatory Agents); 0 (Organophosphorus Compounds); 0 (triphenylphosphonium methylide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180212
[St] Status:MEDLINE


  5 / 19204 MEDLINE  
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[PMID]:27771388
[Au] Autor:Martinez EC; Garg R; Shrivastava P; Gomis S; van Drunen Littel-van den Hurk S
[Ad] Endereço:Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, 107 Wiggins Road, S7N 5E5, Canada; Vaccine and Infectious Disease Organization-International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, Saskatchewan, 120 V
[Ti] Título:Intranasal treatment with a novel immunomodulator mediates innate immune protection against lethal pneumonia virus of mice.
[So] Source:Antiviral Res;135:108-119, 2016 11.
[Is] ISSN:1872-9096
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections in infants and young children. There are no licensed RSV vaccines available, and the few treatment options for high-risk individuals are either extremely costly or cause severe side effects and toxicity. Immunomodulation mediated by a novel formulation consisting of the toll-like receptor 3 agonist poly(I:C), an innate defense regulator peptide and a polyphosphazene (P-I-P) was evaluated in the context of lethal infection with pneumonia virus of mice (PVM). Intranasal delivery of a single dose of P-I-P protected adult mice against PVM when given 24 h prior to challenge. These animals experienced minimal weight loss, no clinical disease, 100% survival, and reduced lung pathology. Similar clinical outcomes were observed in mice treated up to 3 days prior to infection. P-I-P pre-treatment induced early mRNA and protein expression of key chemokine and cytokine genes, reduced the recruitment of neutrophils and eosinophils, decreased virus titers in the lungs, and modulated the delayed exacerbated nature of PVM disease without any short-term side effects. On day 14 post-infection, P-I-P-treated mice were confirmed to be PVM-free. These results demonstrate the capacity of this formulation to prevent PVM and possibly other viral respiratory infections.
[Mh] Termos MeSH primário: Imunidade Inata
Fatores Imunológicos/administração & dosagem
Vírus da Pneumonia Murina/imunologia
Compostos Organofosforados/administração & dosagem
Infecções por Pneumovirus/prevenção & controle
Poli I-C/administração & dosagem
Polímeros/administração & dosagem
[Mh] Termos MeSH secundário: Adjuvantes Imunológicos
Administração Intranasal
Animais
Citocinas/imunologia
Fatores Imunológicos/química
Fatores Imunológicos/imunologia
Pulmão/virologia
Camundongos
Camundongos Endogâmicos BALB C
Compostos Organofosforados/imunologia
Infecções por Pneumovirus/imunologia
Poli I-C/imunologia
Receptor 3 Toll-Like/agonistas
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Adjuvants, Immunologic); 0 (Cytokines); 0 (Immunologic Factors); 0 (Organophosphorus Compounds); 0 (Polymers); 0 (Toll-Like Receptor 3); 0 (poly(phosphazene)); O84C90HH2L (Poly I-C)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161108
[St] Status:MEDLINE


  6 / 19204 MEDLINE  
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[PMID]:29235765
[Au] Autor:Trush MM; Kovalishyn VV; Blagodatnyi VM; Brovarets VS; Pilyo SG; Prokopenko VM; Hodyna DM; Metelytsia LO
[Ti] Título:QSAR studies and antimicrobial potential of 1,3-thiazolylphosphonium salts.
[So] Source:Ukr Biochem J;88(4):57-65, 2016 Jul-Aug.
[Is] ISSN:2409-4943
[Cp] País de publicação:Ukraine
[La] Idioma:eng
[Ab] Resumo:The regression QSAR models were built to predict the antimicrobial activity of new thiazole derivatives. Compounds with high predicting activity were synthesized and evaluated against Gram-positive and Gram-negative bacteria and fungi. 1,3-Thiazole-4-ylphosphonium salts 4 and 5 displayed good antibacterial properties and high antifungal activity. The predictions are in a good agreement with the experiment results, which indicate the good predictive power of the created QSAR models.
[Mh] Termos MeSH primário: Antibacterianos/síntese química
Antifúngicos/síntese química
Compostos Organofosforados/síntese química
Tiazóis/síntese química
[Mh] Termos MeSH secundário: Antibacterianos/farmacologia
Antifúngicos/farmacologia
Bacillus subtilis/efeitos dos fármacos
Bacillus subtilis/crescimento & desenvolvimento
Candida/efeitos dos fármacos
Candida/crescimento & desenvolvimento
Candida albicans/efeitos dos fármacos
Candida albicans/crescimento & desenvolvimento
Candida glabrata/efeitos dos fármacos
Candida glabrata/crescimento & desenvolvimento
Escherichia coli/efeitos dos fármacos
Escherichia coli/crescimento & desenvolvimento
Testes de Sensibilidade Microbiana
Compostos Organofosforados/farmacologia
Pseudomonas aeruginosa/efeitos dos fármacos
Pseudomonas aeruginosa/crescimento & desenvolvimento
Relação Quantitativa Estrutura-Atividade
Tiazóis/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Antifungal Agents); 0 (Organophosphorus Compounds); 0 (Thiazoles)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE
[do] DOI:10.15407/ubj88.04.057


  7 / 19204 MEDLINE  
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[PMID]:28953930
[Au] Autor:Bai Z; Xia P; Wang R; Jiao J; Ru M; Liu J; Liang Z
[Ad] Endereço:College of Life Science, Northwest A&F University, Yangling, China.
[Ti] Título:Molecular cloning and characterization of five SmGRAS genes associated with tanshinone biosynthesis in Salvia miltiorrhiza hairy roots.
[So] Source:PLoS One;12(9):e0185322, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The gibberellin-responsive element binding factor (GRAS) family of proteins plays an important role in the transcriptional regulation of plant development and hormone signaling. To date, there are no reports on GRAS family proteins expressed in Salvia miltiorrhiza. In this study, 28 ESTs that contained the GRAS domain were identified from a S. miltiorrhiza cDNA library. Of these, full-length sequences of five genes were cloned and sequence analysis indicated that all five proteins contain only one GRAS domain and therefore, belong to the GRAS family. The five genes were designated S. miltiorrhiza GRAS1-5 (SmGRAS1-5), which belong to groups I (SmGRAS2 and SmGRAS4), II (SmGRAS3), III (SmGRAS1), and VIII (SmGRAS5) respectively. Additionally, SmGRAS1-5 have different expression patterns in the reed head, stems, leaves, flowers, and roots of S. miltiorrhiza. In this study, the expression of SmGRAS1-5 was sensitive to Gibberellin (GA) stress and that of SmGRAS1, SmGRAS4 and SmGRAS5 was sensitive to Ethephon (Eth) stress respectively. Moreover, S. miltiorrhiza copalyl diphosphate synthases 1 (SmCPS1) and S. miltiorrhiza kaurene synthase like 1 (SmKSL1), which are two key enzymes gene in the diterpenoid biosynthesis pathway, were also response to GA and Eth stress. In addition, Dihydrotanshinone (DT-I) and Tanshinone I (T-I) content were enhanced by GA and Eth stress, Tanshinone IIA (T-IIA) content was increased by GA stress, and the accumulation of Cryptotanshinone (CT) was insensitive to both GA and Eth stress. Together, these results provide insights into functional conservation and diversification of SmGRASs and are useful information for further elucidating SmGRAS functions.
[Mh] Termos MeSH primário: Vias Biossintéticas/genética
Diterpenos Abietanos/biossíntese
Genes de Plantas
Proteínas de Plantas/genética
Raízes de Plantas/genética
Salvia miltiorrhiza/genética
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Sequência de Aminoácidos
Sequência de Bases
Vias Biossintéticas/efeitos dos fármacos
Clonagem Molecular
Sequência Conservada/genética
Perfilação da Expressão Gênica
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
Giberelinas/farmacologia
Especificidade de Órgãos/efeitos dos fármacos
Especificidade de Órgãos/genética
Compostos Organofosforados/farmacologia
Fenantrenos/metabolismo
Filogenia
Proteínas de Plantas/química
Proteínas de Plantas/metabolismo
Raízes de Plantas/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Diterpenes, Abietane); 0 (Gibberellins); 0 (Organophosphorus Compounds); 0 (Phenanthrenes); 0 (Plant Proteins); 03UUH3J385 (tanshinone); XU5R5VQ87S (ethephon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170928
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185322


  8 / 19204 MEDLINE  
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[PMID]:28911104
[Au] Autor:Nußbaumer F; Juen MA; Gasser C; Kremser J; Müller T; Tollinger M; Kreutz C
[Ad] Endereço:Institute of Organic Chemistry, Leopold-Franzens-University of Innsbruck, and Center for Molecular Biosciences Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
[Ti] Título:Synthesis and incorporation of 13C-labeled DNA building blocks to probe structural dynamics of DNA by NMR.
[So] Source:Nucleic Acids Res;45(15):9178-9192, 2017 Sep 06.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We report the synthesis of atom-specifically 13C-modified building blocks that can be incorporated into DNA via solid phase synthesis to facilitate investigations on structural and dynamic features via NMR spectroscopy. In detail, 6-13C-modified pyrimidine and 8-13C purine DNA phosphoramidites were synthesized and incorporated into a polypurine tract DNA/RNA hybrid duplex to showcase the facile resonance assignment using site-specific labeling. We also addressed micro- to millisecond dynamics in the mini-cTAR DNA. This DNA is involved in the HIV replication cycle and our data points toward an exchange process in the lower stem of the hairpin that is up-regulated in the presence of the HIV-1 nucleocapsid protein 7. As another example, we picked a G-quadruplex that was earlier shown to exist in two folds. Using site-specific 8-13C-2'deoxyguanosine labeling we were able to verify the slow exchange between the two forms on the chemical shift time scale. In a real-time NMR experiment the re-equilibration of the fold distribution after a T-jump could be monitored yielding a rate of 0.012 min-1. Finally, we used 13C-ZZ-exchange spectroscopy to characterize the kinetics between two stacked X-conformers of a Holliday junction mimic. At 25°C, the refolding process was found to occur at a forward rate constant of 3.1 s-1 and with a backward rate constant of 10.6 s-1.
[Mh] Termos MeSH primário: DNA Cruciforme/química
DNA/química
Repetição Terminal Longa de HIV
Proteínas do Nucleocapsídeo/química
Compostos Organofosforados/química
RNA/química
[Mh] Termos MeSH secundário: Pareamento de Bases
Isótopos de Carbono
Quadruplex G
HIV-1/química
Marcação por Isótopo
Espectroscopia de Ressonância Magnética
Modelos Moleculares
Mimetismo Molecular
Conformação de Ácido Nucleico
Compostos Organofosforados/síntese química
Técnicas de Síntese em Fase Sólida
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carbon Isotopes); 0 (DNA, Cruciform); 0 (Nucleocapsid Proteins); 0 (Organophosphorus Compounds); 0 (phosphoramidite); 63231-63-0 (RNA); 9007-49-2 (DNA)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170916
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx592


  9 / 19204 MEDLINE  
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[PMID]:28857549
[Au] Autor:Mazzei L; Cianci M; Contaldo U; Musiani F; Ciurli S
[Ad] Endereço:Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna , Bologna, Italy.
[Ti] Título:Urease Inhibition in the Presence of N-(n-Butyl)thiophosphoric Triamide, a Suicide Substrate: Structure and Kinetics.
[So] Source:Biochemistry;56(40):5391-5404, 2017 Oct 10.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The nickel-dependent enzyme urease is a virulence factor for a large number of pathogenic and antibiotic-resistant bacteria, as well as a negative factor for the efficiency of soil nitrogen fertilization for crop production. The use of urease inhibitors to offset these effects requires knowledge, at a molecular level, of their mode of action. The 1.28 Å resolution structure of the enzyme-inhibitor complex obtained upon incubation of Sporosarcina pasteurii urease with N-(n-butyl)thiophosphoric triamide (NBPT), a molecule largely utilized in agriculture, reveals the presence of the monoamidothiophosphoric acid (MATP) moiety, obtained upon enzymatic hydrolysis of the diamide derivative of NBPT (NBPD) to yield n-butyl amine. MATP is bound to the two Ni(II) ions in the active site of urease using a µ -bridging O atom and terminally bound O and NH groups, with the S atom of the thiophosphoric amide pointing away from the metal center. The mobile flap modulating the size of the active site cavity is found in the closed conformation. Docking calculations suggest that the interaction between urease in the open flap conformation and NBPD involves a role for the conserved αArg339 in capturing and orienting the inhibitor prior to flap closure. Calorimetric and spectrophotometric determinations of the kinetic parameters of this inhibition indicate the occurrence of a reversible slow inhibition mode of action, characterized, for both bacterial and plant ureases, by a very small value of the dissociation constant of the urease-MATP complex. No need to convert NBPT to its oxo derivative NBPTO, as previously proposed, is necessary for urease inhibition.
[Mh] Termos MeSH primário: Inibidores Enzimáticos/metabolismo
Inibidores Enzimáticos/farmacologia
Compostos Organofosforados/metabolismo
Compostos Organofosforados/farmacologia
Urease/antagonistas & inibidores
Urease/metabolismo
[Mh] Termos MeSH secundário: Domínio Catalítico
Hidrólise
Cinética
Simulação de Acoplamento Molecular
Sporosarcina/enzimologia
Ureia/metabolismo
Urease/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (N-(n-butyl) thiophosphoric triamide); 0 (Organophosphorus Compounds); 8W8T17847W (Urea); EC 3.5.1.5 (Urease)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170901
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00750


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[PMID]:28851585
[Au] Autor:Worek F; Wosar A; Baumann M; Thiermann H; Wille T
[Ad] Endereço:Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany. Electronic address: franzworek@bundeswehr.org.
[Ti] Título:Development of a sensitive, generic and easy to use organophosphate skin disclosure kit.
[So] Source:Toxicol Lett;280:190-194, 2017 Oct 05.
[Is] ISSN:1879-3169
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Various organophosphorus compounds (OP), primarily the nerve agent VX and other V-agents, are highly toxic to humans after skin exposure. Percutaneous exposure by such OP results in a delayed onset of toxic signs which enables the initiation of specific countermeasures if contamination is detected rapidly. Presently available mobile detection systems can hardly detect skin exposure by low volatile OP. In order to fill this gap an OP skin disclosure kit was developed which should fulfill different requirements, i.e. a high sensitivity, coverage of human toxic OP, easy handling, rapid results, small dimension and weight. The kit includes a cotton swab to sample skin, human AChE as target and chemicals for a color reaction based on the Ellman assay which is recorded by visual inspection. OP is dissolved from the sampler in a test tube filled with phosphate buffer (0.1M, pH 7.4) and incubated with lyophilized human AChE for 1min. The reaction with acetylthiocholine and 5,5'-dithio-bis-2-nitrobenzoic acid (1min) results in a rich yellow color in the absence of OP and in contrast, in transparent or pale yellow buffer in the presence of OP. At the recommended conditions, the limit of detection is 100ng VX and Russian VX and 50ng Chinese VX on plain surface and 200ng VX on rat skin. With activated pesticides, paraoxon and malaoxon, a concentration of ∼10µg can be detected on plain surface. The ready-to-use kit has a weight of 16g and a size of 10×12×1cm. In the end, this kit has the potential to fill a major gap and to enable timely detection of OP skin exposure and initiation of life-saving countermeasures.
[Mh] Termos MeSH primário: Compostos Organofosforados/química
Compostos Organofosforados/toxicidade
Compostos Organotiofosforados/química
Compostos Organotiofosforados/toxicidade
Kit de Reagentes para Diagnóstico
[Mh] Termos MeSH secundário: Administração Cutânea
Animais
Substâncias para a Guerra Química/química
Colorimetria
Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chemical Warfare Agents); 0 (Organophosphorus Compounds); 0 (Organothiophosphorus Compounds); 0 (Reagent Kits, Diagnostic); 9A4381183B (VX)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE



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