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[PMID]:28678435
[Au] Autor:Niaz K; Mabqool F; Khan F; Ismail Hassan F; Baeeri M; Navaei-Nigjeh M; Hassani S; Gholami M; Abdollahi M
[Ad] Endereço:International Campus-Tehran University of Medical Sciences (IC-TUMS), Tehran, Iran.
[Ti] Título:Molecular mechanisms of action of styrene toxicity in blood plasma and liver.
[So] Source:Environ Toxicol;32(10):2256-2266, 2017 Oct.
[Is] ISSN:1522-7278
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Styrene is an aromatic colorless hydrocarbon available in liquid form and highly volatile. In its pure form, it gives a sweet smell. The primary source of exposure in the environment is from plastic materials, rubber industries, packaging materials, insulations, and fiber glass and carpet industry. Natural sources of styrene include: few metabolites in plants which are transferred through food chain. The current study was designed to evaluate styrene toxicity, including: superoxide dismutase (SOD) and protein carbonyl, oxidative stress, glucose-6-phosphatase (G6Pase), glycogen phosphorylase (GP), and phosphoenolpyruvate carboxykinase (PEPCK) activities, adenosine triphosphate (ATP) to adenosine diphosphate (ADP) ratio, and changes in gene expressions such as glutamate dehydrogenase 1 (GLUD1), glucose transporter 2 (GLUT2), and glucokinase (GCK) in the rat liver tissue. For this purpose, styrene was dissolved in corn oil and was administered via gavage, at doses 250, 500, 1000, 1500, 2000, mg/kg/day per mL and control (corn oil) to each rat with one day off in a week, for 42 days. Plasma SOD and protein carbonyl of plasma were significantly up-regulated in 1000, 1500, and 2000 mg/kg/day styrene administrated groups (P < .001). In addition, styrene caused an increase in lipid peroxidation (LPO) and reactive oxygen species (ROS) in the dose-dependent manners in liver tissue (P < .001). Furthermore, the ferrous reducing antioxidant power (FRAP) and total thiol molecules (TTM) in styrene-treated groups were significantly decreased in liver tissue (P < .001) with increasing doses. In treated rats, styrene significantly increased G6Pase activity (P < .001) and down-regulated GP activity (P < .001) as compared to the control group. The PEPCK activity was significantly raised in a dose-dependent manner (P < .001). The ATP/ADP ratio of live cells was significantly raised by increasing the dose (P < .001). There was significantly an up-regulation of GLUD1 and GCK at 2000 mg/kg group (P < .01) and a down-regulation for GLUT2 at the same dose. While in the rest of group, GLUT2 showed up-regulation of relative fold change. By targeting genes such as GLUD1, GLUT2, and GCK, disruption of hepatic gluconeogenesis, glycogenolysis, and insulin secretory functions are obvious. The present study illustrates that induction of oxidative stress followed by changes in G6Pase, GP, and PEPCK activities and the genes responsible for glucose metabolism are the mechanisms of styrene's action in the liver.
[Mh] Termos MeSH primário: Poluentes Ambientais/toxicidade
Fígado/efeitos dos fármacos
Estireno/toxicidade
Superóxido Dismutase/sangue
[Mh] Termos MeSH secundário: Difosfato de Adenosina/metabolismo
Trifosfato de Adenosina/metabolismo
Animais
Regulação da Expressão Gênica
Glucose/metabolismo
Glucose-6-Fosfatase/metabolismo
Glicogênio Fosforilase/metabolismo
Insulina/secreção
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
Peroxidação de Lipídeos
Fígado/metabolismo
Masculino
Estresse Oxidativo
Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo
Carbonilação Proteica
Ratos Wistar
Espécies Reativas de Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Environmental Pollutants); 0 (Insulin); 0 (Intracellular Signaling Peptides and Proteins); 0 (Reactive Oxygen Species); 44LJ2U959V (Styrene); 61D2G4IYVH (Adenosine Diphosphate); 8L70Q75FXE (Adenosine Triphosphate); EC 1.15.1.1 (Superoxide Dismutase); EC 2.4.1.- (Glycogen Phosphorylase); EC 3.1.3.9 (Glucose-6-Phosphatase); EC 4.1.1.32 (Phosphoenolpyruvate Carboxykinase (GTP)); EC 4.1.1.32 (phosphoenolpyruvate carboxykinase 1 (soluble) protein, rat); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171005
[Lr] Data última revisão:
171005
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170706
[St] Status:MEDLINE
[do] DOI:10.1002/tox.22441


  2 / 1632 MEDLINE  
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[PMID]:28478237
[Au] Autor:Lee J; Hong S; Yoon SJ; Kwon BO; Ryu J; Giesy JP; Allam AA; Al-Khedhairy AA; Khim JS
[Ad] Endereço:School of Earth and Environmental Sciences & Research Institute of Oceanography, Seoul National University, Seoul, Republic of Korea.
[Ti] Título:Long-term changes in distributions of dioxin-like and estrogenic compounds in sediments of Lake Sihwa, Korea: Revisited mass balance.
[So] Source:Chemosphere;181:767-777, 2017 Aug.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In the late 1990s, severe pollution by persistent organic contaminants (POCs) was observed in Lake Sihwa by use of a combination of instrumental analyses and in vitro bioassays. To determine long-term changes (>15-year gaps) in distributions of POCs and their potential toxic potencies in the given region, sediment assessments were reconducted. Target chemicals include polycyclic aromatic hydrocarbons (PAHs), alkylphenols (APs), and recently reported emerging chemicals, styrene oligomers (SOs). We employed in vitro bioassays (such as H4IIE-luc and MVLN) to determine potential sediment toxicities. The reduction rates of mean concentrations of APs and SOs in sediments between the two sampling years (1998 vs. 2015) were estimated to be 99% and 67%, respectively. Although APs and SOs significantly declined over the 15-year period, concentrations of PAHs were consistent. Results of the bioassays were consistent with the instrumental data, with relatively great concentrations of all target compounds being detected, particularly in inland creeks. Compositions of all target compounds exhibited changes in homologue patterns over the 15 years considered. This result indicated varying and/or continuing sources in this region. In particular, PAHs were dominated by higher-molecular-weight PAHs (e.g., benzo[g,h,i]perylene and benzo[b]fluoranthene) in recent years. This result might indicate consumption of oil-related fuels. Quantitative potency balance analysis revealed that concentrations of instrumentally-derived equivalents accounted for as little as 18.5% of bioassay-derived equivalents, which indicated significant amounts of unknown and/or unmeasured compounds were present. The present study documented the continuing severe pollution by selected POCs in the Lake Sihwa region over the last 15 years, indicating a lack of management in the area studied.
[Mh] Termos MeSH primário: Dioxinas/análise
Monitoramento Ambiental/métodos
Estrogênios/análise
Sedimentos Geológicos/química
[Mh] Termos MeSH secundário: Poluição Ambiental/análise
Lagos/análise
Compostos Orgânicos
Hidrocarbonetos Aromáticos Policíclicos/análise
República da Coreia
Estireno/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Dioxins); 0 (Estrogens); 0 (Organic Chemicals); 0 (Polycyclic Aromatic Hydrocarbons); 44LJ2U959V (Styrene)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170508
[St] Status:MEDLINE


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[PMID]:28412618
[Au] Autor:Mandegari M; Fashandi H
[Ad] Endereço:Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
[Ti] Título:Untapped potentials of acrylonitrile-butadiene-styrene/polyurethane (ABS/PU) blend membrane to purify dye wastewater.
[So] Source:J Environ Manage;197:464-475, 2017 Jul 15.
[Is] ISSN:1095-8630
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Production of acrylonitrile-butadiene-styrene/polyurethane (ABS/PU) blend membrane with high rejection efficiency for disperse and vat dyes, is introduced as a facile and cost effective technique to purify textile wastewater. In this respect, membranes are produced using commercially available polymers, i.e. ABS and PU, with different compositions (ABS/PU: 100/0, 80/20, 70/30, 60/40 and 50/50 w/w) through wet casting. Casting solutions with concentration of 30 wt% are prepared using two different solvents, i.e. dimethylformamide (DMF) and N-methyl-2- pyrrolidone (NMP). The prepared membranes are characterized using a variety of analytical techniques including SEM imaging, FTIR spectroscopy, dry and wet gas permeation, evaluation of reusability, antifouling and mechanical properties, photostability, surface hydrophilicity and pure water permeability (PWP) of the produced membranes. According to the results, irrespective of solvent type, ABS/PU membranes with higher PU content have lower porosity and smaller pore size both of which contribute to enhanced dye rejection efficiency. This is while the impact of PU content on the photostability of ABS/PU membranes was found to be negligible. Additionally, the produced ABS/PU membranes exhibit good reusability and antifouling properties. However, the mechanical properties of ABS/PU membranes with higher PU contents are inferior to those with lower PU contents. This contrast highlights the prominence of optimum PU content to make a trade-off between dye rejection efficiency and mechanical properties. In this regard, ABS/PU (60/40 w/w) membrane is recognized as the one with optimum composition. Furthermore, it was found that regardless of PU content, membranes cast from DMF-based solutions exhibit superior rejection performance over those cast from NMP-based solutions. Overall, one can witness that employing ABS/PU membranes provides a meritorious and clean approach to refine disperse and vat dye wastewaters, a great threat to the environment and human health.
[Mh] Termos MeSH primário: Águas Residuais
Poluentes Químicos da Água
[Mh] Termos MeSH secundário: Acrilonitrila
Butadienos
Seres Humanos
Poliuretanos
Estireno
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Butadienes); 0 (Polyurethanes); 0 (Waste Water); 0 (Water Pollutants, Chemical); 44LJ2U959V (Styrene); MP1U0D42PE (Acrylonitrile)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170417
[St] Status:MEDLINE


  4 / 1632 MEDLINE  
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[PMID]:28325446
[Au] Autor:Hernández-Morera P; Travieso-González CM; Castaño-González I; Mompeó-Corredera B; Ortega-Santana F
[Ad] Endereço:IUMA Information and Communication Systems, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira, 35017 - Las Palmas de Gran Canaria, Spain; Department of Telematic Engineering, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira, 35017 - Las Palmas de Gran C
[Ti] Título:Segmentation of elastic fibres in images of vessel wall sections stained with Weigert's resorcin-fuchsin.
[So] Source:Comput Methods Programs Biomed;142:43-54, 2017 Apr.
[Is] ISSN:1872-7565
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:BACKGROUND AND OBJECTIVE: The elastic fibres are an essential component of the extracellular matrix in blood vessel walls that allows a long-range of deformability and passive recoil without energy input. The quantitative determination of elastic fibres will provide information on the state of the vascular wall and to determine the role and behaviour of this key structural element in different physiological and pathological vascular processes. METHODS: We present a segmentation method to identify and quantify elastic fibres based on a local threshold technique and some morphological characteristics measured on the segmented objects that facilitate the discrimination between elastic fibres and other image components. The morphological characteristics analysed are the thickness and the length of an object. RESULTS: The segmentation method was evaluated using an image database of vein sections stained with Weigert's resorcin-fuchsin. The performance results are based on a ground truth generated manually resulting in values of sensitivity greater than 80% with the exception in two samples, and specificity values above 90% for all samples. Medical specialists carried out a visual evaluation where the observations indicate a general agreement on the segmentation results' visual quality, and the consistency between the methodology proposed and the subjective observation of the doctors for the evaluation of pathological changes in vessel wall. CONCLUSIONS: The proposed methodology provides more objective measurements than the qualitative methods traditionally used in the histological analysis, with a significant potential for this method to be used as a diagnostic aid for many other vascular pathological conditions and in similar tissues such as skin and mucous membranes.
[Mh] Termos MeSH primário: Tecido Elástico/diagnóstico por imagem
Veia Safena/patologia
Coloração e Rotulagem/métodos
Doenças Vasculares/diagnóstico
[Mh] Termos MeSH secundário: Algoritmos
Cadáver
Feminino
Histologia
Seres Humanos
Processamento de Imagem Assistida por Computador
Masculino
Modelos Estatísticos
Plastificantes/química
Resorcinóis/química
Corantes de Rosanilina/química
Sensibilidade e Especificidade
Software
Estireno/química
Xilenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Plasticizers); 0 (Resorcinols); 0 (Rosaniline Dyes); 0 (Xylenes); 44LJ2U959V (Styrene); YUL4LO94HK (resorcinol)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE


  5 / 1632 MEDLINE  
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[PMID]:28276244
[Au] Autor:Lligadas G; Grama S; Percec V
[Ad] Endereço:Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104-6323, United States.
[Ti] Título:Recent Developments in the Synthesis of Biomacromolecules and their Conjugates by Single Electron Transfer-Living Radical Polymerization.
[So] Source:Biomacromolecules;18(4):1039-1063, 2017 Apr 10.
[Is] ISSN:1526-4602
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Single electron transfer-living radical polymerization (SET-LRP) represents a robust and versatile tool for the synthesis of vinyl polymers with well-defined topology and chain end functionality. The crucial step in SET-LRP is the disproportionation of the Cu(I)X generated by activation with Cu(0) wire, powder, or nascent Cu(0) generated in situ into nascent, extremely reactive Cu(0) atoms and nanoparticles and Cu(II)X . Nascent Cu(0) activates the initiator and dormant chains via a homogeneous or heterogeneous outer-sphere single-electron transfer mechanism (SET-LRP). SET-LRP provides an ultrafast polymerization of a plethora of monomers (e.g., (meth)-acrylates, (meth)-acrylamides, styrene, and vinyl chloride) including hydrophobic and water insoluble to hydrophilic and water soluble. Some advantageous features of SET-LRP are (i) the use of Cu(0) wire or powder as readily available catalysts under mild reaction conditions, (ii) their excellent control over molecular weight evolution and distribution as well as polymer chain ends, (iii) their high functional group tolerance allowing the polymerization of commercial-grade monomers, and (iv) the limited purification required for the resulting polymers. In this Perspective, we highlight the recent advancements of SET-LRP in the synthesis of biomacromolecules and of their conjugates.
[Mh] Termos MeSH primário: Transporte de Elétrons
Elétrons
Substâncias Macromoleculares/síntese química
Polimerização
[Mh] Termos MeSH secundário: Acrilamidas/química
Acrilatos/química
Cobre/química
Interações Hidrofóbicas e Hidrofílicas
Peso Molecular
Nanopartículas/química
Estireno/química
Compostos de Vinila/química
Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acrylamides); 0 (Acrylates); 0 (Macromolecular Substances); 0 (Vinyl Compounds); 059QF0KO0R (Water); 44LJ2U959V (Styrene); 789U1901C5 (Copper)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170310
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biomac.7b00197


  6 / 1632 MEDLINE  
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[PMID]:28169473
[Au] Autor:Song YK; Kim B; Lee TH; Kim JC; Nam JH; Noh SM; Park YI
[Ad] Endereço:Research Center for Green Fine Chemicals, Korea Research Institute of Chemical Technology, Ulsan, 44412, Republic of Korea.
[Ti] Título:Fluorescence Detection of Microcapsule-Type Self-Healing, Based on Aggregation-Induced Emission.
[So] Source:Macromol Rapid Commun;38(6), 2017 Mar.
[Is] ISSN:1521-3927
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:An extrinsic self-healing coating system containing tetraphenylethylene (TPE) in microcapsules was monitored by measuring aggregation-induced emission (AIE). The core healing agent comprised of methacryloxypropyl-terminated polydimethylsiloxane, styrene, benzoin isobutyl ether, and TPE was encapsulated in a urea-formaldehyde shell. The photoluminescence of the healing agent in the microcapsules was measured that the blue emission intensity dramatically increased and the storage modulus also increased up to 10 Pa after the photocuring. These results suggested that this formulation might be useful as a self-healing material and as an indicator of the self-healing process due to the dramatic change in fluorescence during photocuring. To examine the ability of the healing agent to repair damage to a coating, a self-healing coating containing embedded microcapsules was scribed with a razor. As the healing process proceeded, blue light fluorescence emission was observed at the scribed regions. This observation suggested that self-healing could be monitored using the AIE fluorescence.
[Mh] Termos MeSH primário: Dimetilpolisiloxanos/química
Éteres/química
Fluorescência
Estilbenos/análise
Estilbenos/química
Estireno/química
[Mh] Termos MeSH secundário: Cápsulas
Formaldeído/química
Estrutura Molecular
Tamanho da Partícula
Processos Fotoquímicos
Propriedades de Superfície
Ureia/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Capsules); 0 (Dimethylpolysiloxanes); 0 (Ethers); 0 (Stilbenes); 0 (tetraphenylethylene); 1HG84L3525 (Formaldehyde); 44LJ2U959V (Styrene); 63148-62-9 (baysilon); 8W8T17847W (Urea)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170417
[Lr] Data última revisão:
170417
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170208
[St] Status:MEDLINE
[do] DOI:10.1002/marc.201600657


  7 / 1632 MEDLINE  
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[PMID]:28161337
[Au] Autor:Liu G; Liao Y; Ma X
[Ad] Endereço:Guangdong Key Laboratory of Efficient and Clean Energy Utilization Institutes, School of Electric Power, South China University of Technology, Guangzhou 510640, PR China.
[Ti] Título:Thermal behavior of vehicle plastic blends contained acrylonitrile-butadiene-styrene (ABS) in pyrolysis using TG-FTIR.
[So] Source:Waste Manag;61:315-326, 2017 Mar.
[Is] ISSN:1879-2456
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:As important plastic blends in End-of-Life vehicles (ELV), pyrolysis profiles of ABS/PVC, ABS/PA6 and ABS/PC were investigated using thermogravimetric-Fourier transform infrared spectrometer (TG-FTIR). Also, CaCO was added as plastic filler to discuss its effects on the pyrolysis of these plastics. The results showed that the interaction between ABS and PVC made PVC pyrolysis earlier and HCl emission slightly accelerated. The mixing of ABS and PA6 made their decomposition temperature closer, and ketones in PA6 pyrolysis products were reduced. The presence of ABS made PC pyrolysis earlier, and phenyl compounds in PC pyrolysis products could be transferred into alcohol or H O. The interaction between ABS and other polymers in pyrolysis could be attributed to the intermolecular radical transfer, and free radicals from the polymer firstly decomposed led to a fast initiation the decomposition of the other polymer. As plastic filler, CaCO promoted the thermal decomposition of PA6 and PC, and had no obvious effects on ABS and PVC pyrolysis process. Also, CaCO made the pyrolysis products from PA6 and PC further decomposed into small-molecule compounds like CO . The kinetics analysis showed that isoconversional method like Starink method was more suitable for these polymer blends. Starink method showed the average activation energy of ABS50/PVC50, ABS50/PA50 and ABS50/PC50 was 186.63kJ/mol, 239.61kJ/mol and 248.95kJ/mol, respectively, and the interaction among them could be reflected by the activation energy variation.
[Mh] Termos MeSH primário: Acrilonitrila/química
Automóveis
Butadienos/química
Plásticos/química
Estireno/química
Gerenciamento de Resíduos/métodos
[Mh] Termos MeSH secundário: Carbonato de Cálcio/química
Plásticos/análise
Espectroscopia de Infravermelho com Transformada de Fourier
Termogravimetria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Butadienes); 0 (Plastics); 44LJ2U959V (Styrene); H0G9379FGK (Calcium Carbonate); MP1U0D42PE (Acrylonitrile)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170703
[Lr] Data última revisão:
170703
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170206
[St] Status:MEDLINE


  8 / 1632 MEDLINE  
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[PMID]:28153386
[Au] Autor:Crabo AG; Singh B; Nguyen T; Emami S; Gassner GT; Sazinsky MH
[Ad] Endereço:Department of Chemistry, Pomona College, Claremont, CA, United States.
[Ti] Título:Structure and biochemistry of phenylacetaldehyde dehydrogenase from the Pseudomonas putida S12 styrene catabolic pathway.
[So] Source:Arch Biochem Biophys;616:47-58, 2017 Feb 15.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Phenylacetaldehyde dehydrogenase catalyzes the NAD -dependent oxidation of phenylactealdehyde to phenylacetic acid in the styrene catabolic and detoxification pathway of Pseudomonas putida (S12). Here we report the structure and mechanistic properties of the N-terminally histidine-tagged enzyme, NPADH. The 2.83 Å X-ray crystal structure is similar in fold to sheep liver cytosolic aldehyde dehydrogenase (ALDH1), but has unique set of intersubunit interactions and active site tunnel for substrate entrance. In solution, NPADH occurs as 227 kDa homotetramer. It follows a sequential reaction mechanism in which NAD serves as both the leading substrate and homotropic allosteric activator. In the absence of styrene monooxygenase reductase, which regenerates NAD from NADH in the first step of styrene catabolism, NPADH is inhibited by a ternary complex involving NADH, product, and phenylacetaldehyde, substrate. Each oligomerization domain of NPADH contains a six-residue insertion that extends this loop over the substrate entrance tunnel of a neighboring subunit, thereby obstructing the active site of the adjacent subunit. This feature could be an important factor in the homotropic activation and product inhibition mechanisms. Compared to ALDH1, the substrate channel of NPADH is narrower and lined with more aromatic residues, suggesting a means for enhancing substrate specificity.
[Mh] Termos MeSH primário: Aldeído Oxirredutases/química
Proteínas de Bactérias/química
Proteínas de Escherichia coli/química
Pseudomonas putida/enzimologia
[Mh] Termos MeSH secundário: Aldeídos/química
Sítio Alostérico
Animais
Catálise
Domínio Catalítico
Bovinos
Clonagem Molecular
Cristalografia por Raios X
Cinética
Conformação Molecular
NAD/química
Domínios Proteicos
Pseudomonas
Ovinos
Espectrometria de Fluorescência
Estireno/química
Especificidade por Substrato
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aldehydes); 0 (Bacterial Proteins); 0 (Escherichia coli Proteins); 0U46U6E8UK (NAD); 44LJ2U959V (Styrene); EC 1.2.- (Aldehyde Oxidoreductases); EC 1.2.1.39 (phenylacetaldehyde dehydrogenase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170515
[Lr] Data última revisão:
170515
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170204
[St] Status:MEDLINE


  9 / 1632 MEDLINE  
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[PMID]:28107715
[Au] Autor:Montagnolli RN; Lopes PR; Cruz JM; Claro MT; Quiterio GM; Bidoia ED
[Ad] Endereço:Departamento de Bioquímica e Microbiologia, Instituto de Biociências, UNESP - São Paulo State University, Avenida 24 A, 1515 - Bela Vista, 13506-900, Rio Claro, SP, Brazil.
[Ti] Título:Metabolical shifts towards alternative BTEX biodegradation intermediates induced by perfluorinated compounds in firefighting foams.
[So] Source:Chemosphere;173:49-60, 2017 Apr.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The type and concentration of perfluorinated compounds (PFCs) can induce different types of enzymes and promote alternate patterns of BTEX transformation. However, it is not known how the presence of active fluorocarbon-degrading microbial populations affects the transformation of BTEX. In addition to chemical analysis at the molecular level, our research approached the aqueous film forming fire-fighting foams (AFFF) and BTEX co-contamination at a large-scale with respirometers to quantify the total microbial metabolism of soil via CO output levels. The intended outcome of this research was to obtain and characterize shifts in BTEX degradation at a set realistic environmental condition while measuring byproducts and CO production. Both methodologies complimentarily provided an in-depth knowledge of the environmental behavior of fire-fighting foams. The biodegradation was monitored using headspace sampling and two types of gas chromatography: thermal conductivity detector and flame ionization detector. Headspace samples were periodically withdrawn for BTEX biodegradation and CO production analysis. Our research suggests the discovery of an altered metabolic pathway in aromatic hydrocarbons biodegradation that is directly affected by fluorinated substances. The fluorinated compounds affected the BTEX biodegradation kinetics, as PFCs may contribute to a shift in styrene and catechol concentrations in co-contamination scenarios. A faster production of styrene and catechol was detected. Catechol is also rapidly consumed, thus undergoing further metabolic stages earlier under the presence of PFCs. The release of AFFF compounds not only changes byproducts output but also drastically disturbs the soil microbiota according to the highly variable CO yields. Therefore, we observed a high sensitivity of microbial consortia due to PFCs in the AFFF formulation, therefore shifting their BTEX degradation routes in terms of intermediate products concentration.
[Mh] Termos MeSH primário: Bactérias/metabolismo
Derivados de Benzeno/metabolismo
Biodegradação Ambiental
Retardadores de Chama/farmacologia
Fluorcarbonetos/farmacologia
Microbiologia do Solo
[Mh] Termos MeSH secundário: Bactérias/efeitos dos fármacos
Derivados de Benzeno/química
Catecóis/metabolismo
Monitoramento Ambiental
Fluorcarbonetos/química
Solo/química
Estireno/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Benzene Derivatives); 0 (Catechols); 0 (Flame Retardants); 0 (Fluorocarbons); 0 (Soil); 44LJ2U959V (Styrene); LF3AJ089DQ (catechol)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170121
[St] Status:MEDLINE


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[PMID]:27993394
[Au] Autor:Mao Z; Chen Z
[Ad] Endereço:Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China; State Key Laboratory of Transducer Technology, Chinese Academy of Sciences, Beijing 10080, China.
[Ti] Título:Monolithic column modified with bifunctional ionic liquid and styrene stationary phases for capillary electrochromatography.
[So] Source:J Chromatogr A;1480:99-105, 2017 Jan 13.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A novel monolithic column with ionic liquid and styrene-modified bifunctional group was prepared for capillary electrochromatography (CEC) by in situ copolymerization in a ternary porogenic solvent. Ionic liquid (1-allyl-methylimidazolium chloride, AlMeIm Cl ) and styrene served as the bifunctional monomer, while ethylene dimethacrylate (EDMA) was used as the cross-linker. The monomer of AlMeIm Cl was introduced as anion-exchange group, while styrene as hydrophobic and aromatic group; the similar conjugated structure in AlMeIm Cl and styrene was beneficial for offeing obvious synergistic effect. The bifunctional stationary phase possessed powerful selectivity for the separation of neutral compounds, acidic analytes and phenols. The highest column efficiency was 2.70×10 platesm (theoretical plates, N) for toluene. A relatively strong electroosmotic flow (EOF) was obtained in a wide range of pH values from 2.0 to 12.0, which could successfully achieve the rapid separation of the analytes within 10min. The proposed monolithic column was characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). The results indicated that the resultant monolithic column had good permeability and excellent mechanical stability. Good reproducibility was obtained with relative standard deviations (RSDs) of the retention time in the range of 0.24-0.47% and 0.81-2.17% for run-to-run (n=5) and day-to-day (n=5), while 1.09-2.70% and 0.98-1.70% for column-to-column (n=3) and batch-to-batch (n=3), respectively. The combination of AlMeIm Cl and styrene was a promising option in the fabrication of the organic polymer monolithic column.
[Mh] Termos MeSH primário: Eletrocromatografia Capilar/métodos
Líquidos Iônicos/química
Estireno/química
[Mh] Termos MeSH secundário: Eletro-Osmose
Concentração de Íons de Hidrogênio
Interações Hidrofóbicas e Hidrofílicas
Metacrilatos/química
Microscopia Eletrônica de Varredura
Fenóis/química
Fenóis/isolamento & purificação
Polímeros/química
Reprodutibilidade dos Testes
Solventes
Espectroscopia de Infravermelho com Transformada de Fourier
Tolueno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ionic Liquids); 0 (Methacrylates); 0 (Phenols); 0 (Polymers); 0 (Solvents); 3FPU23BG52 (Toluene); 44LJ2U959V (Styrene); 7BK5G69305 (ethylene dimethacrylate)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161221
[St] Status:MEDLINE



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