Base de dados : MEDLINE
Pesquisa : G01.202 [Categoria DeCS]
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[PMID]:28865349
[Au] Autor:Li X; Zhang D; Sheng F; Qing H
[Ad] Endereço:Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Conservancy, Chengdu 610041, China.
[Ti] Título:Adsorption characteristics of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡) by four kinds of immobilized fungi residues.
[So] Source:Ecotoxicol Environ Saf;147:357-366, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:This study investigated the adsorption characteristics of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡) by immobilized Flammulina velutipes, Auricularia polytricha, Pleurotus eryngii and Pleurotus ostreatus residues. Lagergren model, elovich and intraparticle diffusion model were used to present the adsorption kinetics, and it was proved that Langmuir isotherm model and pseudo-second order kinetics are the best suitable model with high correlation coefficient to characterize the adsorption process of Copper (â…¡), Zinc (â…¡) and Mercury (â…¡). The results showed that adsorption process finished in 120min at pH 6.0. The adsorption rate of Cu , Zn and Hg were reached to 53.8-84.1% of total in the initial 60min, and finished in 120min. Ion exchange and complexation of F. velutipes were the main mechanisms for adsorption of metal ions by characterizations of Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). In addition the functional group of cell walls such as hydroxyl, amide, carbonyl, phosphoric played a critical role in ions adsorption of edible mushroom residues. Cu , Zn and Hg in wastewater could be efficiently removed by F. velutipes residue with removal ratio of 73.11%, 66.67% and 69.35%, respectively.
[Mh] Termos MeSH primário: Agaricales/química
Cobre/análise
Mercúrio/análise
Modelos Teóricos
Poluentes Químicos da Água/análise
Zinco/análise
[Mh] Termos MeSH secundário: Adsorção
Cobre/química
Difusão
Concentração de Íons de Hidrogênio
Íons
Cinética
Mercúrio/química
Resíduos Sólidos/análise
Termodinâmica
Águas Residuais/química
Poluentes Químicos da Água/química
Purificação da Água/métodos
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Solid Waste); 0 (Waste Water); 0 (Water Pollutants, Chemical); 789U1901C5 (Copper); FXS1BY2PGL (Mercury); J41CSQ7QDS (Zinc)
[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:170903
[St] Status:MEDLINE


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[PMID]:29402931
[Au] Autor:Bianchi F; Syga L; Moiset G; Spakman D; Schavemaker PE; Punter CM; Seinen AB; van Oijen AM; Robinson A; Poolman B
[Ad] Endereço:Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9700AB, Groningen, The Netherlands.
[Ti] Título:Steric exclusion and protein conformation determine the localization of plasma membrane transporters.
[So] Source:Nat Commun;9(1):501, 2018 02 05.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The plasma membrane (PM) of Saccharomyces cerevisiae contains membrane compartments, MCC/eisosomes and MCPs, named after the protein residents Can1 and Pma1, respectively. Using high-resolution fluorescence microscopy techniques we show that Can1 and the homologous transporter Lyp1 are able to diffuse into the MCC/eisosomes, where a limited number of proteins are conditionally trapped at the (outer) edge of the compartment. Upon addition of substrate, the immobilized proteins diffuse away from the MCC/eisosomes, presumably after taking a different conformation in the substrate-bound state. Our data indicate that the mobile fraction of all integral plasma membrane proteins tested shows extremely slow Brownian diffusion through most of the PM. We also show that proteins with large cytoplasmic domains, such as Pma1 and synthetic chimera of Can1 and Lyp1, are excluded from the MCC/eisosomes. We hypothesize that the distinct localization patterns found for these integral membrane proteins in S. cerevisiae arises from a combination of slow lateral diffusion, steric exclusion, and conditional trapping in membrane compartments.
[Mh] Termos MeSH primário: Sistemas de Transporte de Aminoácidos Básicos/química
Membrana Celular/metabolismo
ATPases Translocadoras de Prótons/química
Proteínas de Saccharomyces cerevisiae/química
Saccharomyces cerevisiae/metabolismo
[Mh] Termos MeSH secundário: Sistemas de Transporte de Aminoácidos Básicos/metabolismo
Membrana Celular/ultraestrutura
Difusão
Recuperação de Fluorescência Após Fotodegradação
Cinética
Microdomínios da Membrana
Conformação Proteica
Transporte Proteico
ATPases Translocadoras de Prótons/metabolismo
Saccharomyces cerevisiae/ultraestrutura
Proteínas de Saccharomyces cerevisiae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acid Transport Systems, Basic); 0 (CAN1 protein, S cerevisiae); 0 (LYP1 protein, S cerevisiae); 0 (Saccharomyces cerevisiae Proteins); EC 3.6.1.- (PMA1 protein, S cerevisiae); EC 3.6.3.14 (Proton-Translocating ATPases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-018-02864-2


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[PMID]:27775923
[Au] Autor:Ortuño-Lizarán I; Vilariño-Feltrer G; Martínez-Ramos C; Pradas MM; Vallés-Lluch A
[Ad] Endereço:Centre for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Cno. de Vera s/n, E-46022, Valencia, Spain. Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Spain.
[Ti] Título:Influence of synthesis parameters on hyaluronic acid hydrogels intended as nerve conduits.
[So] Source:Biofabrication;8(4):045011, 2016 10 24.
[Is] ISSN:1758-5090
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Hydrogels have widely been proposed lately as strategies for neural tissue regeneration, but there are still some issues to be solved before their efficient use in tissue engineering of trauma, stroke or the idiopathic degeneration of the nervous system. In a previous work of the authors a novel Schwann-cell structure with the shape of a hollow cylinder was obtained using a three-dimensional conduit based in crosslinked hyaluronic acid as template. This original engineered tissue of tightly joined Schwann cells obtained in a conduit lumen having 400 µm in diameter is a consequence of specific cell-material interactions. In the present work we analyze the influence of the hydrogel concentration and of the drying process on the physicochemical and biological performance of the resulting tubular scaffolds, and prove that the cylinder-like cell sheath obtains also in scaffolds of a larger inner diameter. The diffusion of glucose and of the protein BSA through the scaffolds is studied and characterized, as well as the enzymatic degradation kinetics of the lyophilized conduits. This can be modulated from a couple of weeks to several months by varying the concentration of hyaluronic acid in the starting solution. These findings allow to improve the performance of hyaluronan intended for neural conduits, and open the way to scaffolds with tunable degradation rate adapted to the site and severity of the injury.
[Mh] Termos MeSH primário: Ácido Hialurônico/química
Hidrogéis/química
Tecidos Suporte/química
[Mh] Termos MeSH secundário: Animais
Bovinos
Linhagem Celular
Proliferação Celular
Sobrevivência Celular
Difusão
Glucose/metabolismo
Hidrogéis/síntese química
Regeneração Nervosa
Porosidade
Ratos
Células de Schwann/citologia
Células de Schwann/metabolismo
Células de Schwann/patologia
Soroalbumina Bovina/metabolismo
Engenharia Tecidual
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Hydrogels); 27432CM55Q (Serum Albumin, Bovine); 9004-61-9 (Hyaluronic Acid); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE


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[PMID]:29028599
[Au] Autor:Kotzakoulakis K; George SC
[Ad] Endereço:Department of Earth and Planetary Sciences and Macquarie University Marine Research Centre, Macquarie University, North Ryde, NSW, 2109, Australia. Electronic address: konstantinos.kotzakoulakis@gmail.com.
[Ti] Título:Predicting the weathering of fuel and oil spills: A diffusion-limited evaporation model.
[So] Source:Chemosphere;190:442-453, 2018 Jan.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The majority of the evaporation models currently available in the literature for the prediction of oil spill weathering do not take into account diffusion-limited mass transport and the formation of a concentration gradient in the oil phase. The altered surface concentration of the spill caused by diffusion-limited transport leads to a slower evaporation rate compared to the predictions of diffusion-agnostic evaporation models. The model presented in this study incorporates a diffusive layer in the oil phase and predicts the diffusion-limited evaporation rate. The information required is the composition of the fluid from gas chromatography or alternatively the distillation data. If the density or a single viscosity measurement is available the accuracy of the predictions is higher. Environmental conditions such as water temperature, air pressure and wind velocity are taken into account. The model was tested with synthetic mixtures, petroleum fuels and crude oils with initial viscosities ranging from 2 to 13,000 cSt. The tested temperatures varied from 0 °C to 23.4 °C and wind velocities from 0.3 to 3.8 m/s. The average absolute deviation (AAD) of the diffusion-limited model ranged between 1.62% and 24.87%. In comparison, the AAD of a diffusion-agnostic model ranged between 2.34% and 136.62% against the same tested fluids.
[Mh] Termos MeSH primário: Difusão
Modelos Teóricos
Poluição por Petróleo/análise
Poluentes Químicos da Água/análise
Tempo (Meteorologia)
[Mh] Termos MeSH secundário: Cromatografia Gasosa
Temperatura Ambiente
Vento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Water Pollutants, Chemical)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171014
[St] Status:MEDLINE


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[PMID]:29276081
[Au] Autor:Uchiyama S; Sasaki T; Ishihara R; Fujiwara K; Sugo T; Umeno D; Saito K
[Ad] Endereço:Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan.
[Ti] Título:High-resolution separation of neodymium and dysprosium ions utilizing extractant-impregnated graft-type particles.
[So] Source:J Chromatogr A;1533:10-16, 2018 Jan 19.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:An efficient method for rare metal recovery from environmental water and urban mines is in high demand. Toward rapid and high-resolution rare metal ion separation, a novel bis(2-ethylhexyl) phosphate (HDEHP)-impregnated graft-type particle as a filler for a chromatography column is proposed. To achieve rapid and high-resolution separation, a convection-flow-aided elution mode is required. The combination of 35 µm non-porous particles and a polymer-brush-rich particle structure minimizes the distance from metal ion binding sites to the convection flow in the column, resulting in minimized diffusional mass transfer resistance and the convection-flow-aided elution mode. The HDEHP-impregnated graft-type non-porous-particle-packed cartridge developed in this study exhibited a higher separation performance for model rare metals, neodymium (III) and dysprosium (III) ions, and a narrower peak at a higher linear velocity, than those of previous HDEHP-impregnated fiber-packed and commercially available Lewatit VP OC 1026-packed cartridges.
[Mh] Termos MeSH primário: Técnicas de Química Analítica/métodos
Disprósio/isolamento & purificação
Neodímio/isolamento & purificação
[Mh] Termos MeSH secundário: Cromatografia
Difusão
Disprósio/química
Íons/química
Íons/isolamento & purificação
Metais/química
Neodímio/química
Polímeros/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Metals); 0 (Polymers); 1D4N45714Q (Dysprosium); 2I87U3734A (Neodymium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171226
[St] Status:MEDLINE


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[PMID]:29388752
[Au] Autor:Zhang M; Sai B; Cao P; Li Z; Zhang L; Shuai C; Wang X; Wang J; Li G; Xiang J; Tang J
[Ti] Título:Iron Oxide Nanoparticles Synergize with Erlotinib to Suppress Refractory Non-Small Cell Lung Cancer Cell Proliferation Through the Inhibition of ErbB/PI3K/AKT and PTEN Activation.
[So] Source:J Biomed Nanotechnol;13(4):458-68, 2017 Apr.
[Is] ISSN:1550-7033
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Non-small cell lung cancer (NSCLC) accounts for 85% of lung cancer cases. EGFR tyrosine kinase inhibitors (EGFR-TKIs) such as erlotinib and gefitinib, are currently approved for the management of NSCLC. However, primary and acquired resistances to EGFR-TKIs are the major obstacles in the treatment of NSCLC. These resistances have been associated with the development of secondary mutations in EGFR or continued oncogenic signaling despite TKI treatment. In this study, NSCLC cells with wild-type EGFR, A549, H460, H358, H157 which do not respond to EGFR-TKIs, were used. We investigated whether a combination therapy of erlotinib plus iron oxide nanoparticles (IONPs) could sensitize NSCLC cells to erlotinib-induced cancer inhibition. In the 4 NSCLC cells investigated, erlotinib and IONPs combination therapy obviously inhibited NSCLC proliferation in vitro and in vivo, compared with erlotinib treatment alone. This effect was not dependent on erlotinib dose. Activation of ErbB3 was observed in these refractory NSCLC cells. Combined with IONPs, erlotinib could block ErbB3 activity and induce the expression of PTEN, which in turn inhibited the downstream PI3KAKT signaling pathway. These data demonstrate the therapeutic potential of biocompatible IONPs in combination with EGFR-TKIs in NSCLC, thus expanding and repurposing the current therapy for NSCLC.
[Mh] Termos MeSH primário: Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico
Carcinoma Pulmonar de Células não Pequenas/metabolismo
Neoplasias Pulmonares/tratamento farmacológico
Neoplasias Pulmonares/metabolismo
PTEN Fosfo-Hidrolase/metabolismo
[Mh] Termos MeSH secundário: Células A549
Apoptose/efeitos dos fármacos
Carcinoma Pulmonar de Células não Pequenas/patologia
Proliferação Celular/efeitos dos fármacos
Difusão
Regulação para Baixo/efeitos dos fármacos
Combinação de Medicamentos
Cloridrato de Erlotinib/administração & dosagem
Cloridrato de Erlotinib/química
Seres Humanos
Neoplasias Pulmonares/patologia
Nanopartículas de Magnetita/administração & dosagem
Nanocápsulas/administração & dosagem
Nanocápsulas/química
Proteína Oncogênica v-akt/metabolismo
Fosfatidilinositol 3-Quinases/metabolismo
Receptor do Fator de Crescimento Epidérmico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Drug Combinations); 0 (Magnetite Nanoparticles); 0 (Nanocapsules); DA87705X9K (Erlotinib Hydrochloride); EC 2.7.1.- (Phosphatidylinositol 3-Kinases); EC 2.7.10.1 (EGFR protein, human); EC 2.7.10.1 (Receptor, Epidermal Growth Factor); EC 2.7.11.1 (Oncogene Protein v-akt); EC 3.1.3.67 (PTEN Phosphohydrolase); EC 3.1.3.67 (PTEN protein, human)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180202
[St] Status:MEDLINE


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[PMID]:29384621
[Au] Autor:Jasim R; Schneider EK; Han M; Azad MAK; Hussein M; Nowell C; Baker MA; Wang J; Li J; Velkov T
[Ti] Título:A Fresh Shine onCystic Fibrosis Inhalation Therapy: Antimicrobial Synergy of Polymyxin B in Combination with Silver Nanoparticles.
[So] Source:J Biomed Nanotechnol;13(4):447-57, 2017 Apr.
[Is] ISSN:1550-7033
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This in vitro study aimed to investigate the synergistic antibacterial activity of polymyxin B in combination with 2 nm silver nanoparticles (NPs) against Gram-negative pathogens commonly isolated from the cystic fibrosis (CF) lung. The in vitro synergistic activity of polymyxin B with silver NPs was assessed using the checkerboard assay against polymyxinsusceptible and polymyxin-resistant Pseudomonas aeruginosa isolates from the lungs of CF patients. The combination was also examined against the Gram-negative species Haemophilus influenzae, Burkholderia cepacia, Burkholderia pseudomallei, Stenotrophomonas maltophilia, Klebsiella pneumoniae and Acinetobacter baumannii that are less common in the CF lung. The killing kinetics of the polymyxin B-silver NPs combinations was assessed against P. aeruginosa by static time-kill assays over 24 h. Polymyxin B and silver NPs alone were not active against polymyxin-resistant (MIC ≥4 mg/L) P. aeruginosa. Whereas, the combination of a clinically-relevant concentration of polymyxin B (2 mg/L) with silver NPs (4 mg/L) successfully inhibited the growth of polymyxin-resistant P. aeruginosa isolates from CF patients as demonstrated by ≥2 log10 decrease in bacterial count (CFU/mL) after 24 h. Treatment of P. aeruginosa cells with the combination induced cytosolic GFP release and an increase of cellular reactive oxygen species. In the nitrocefin assay, the combination displayed a membrane permeabilizing activity superior to each of the drugs alone. The combination of polymyxin B and silver NPs displays excellent synergistic activity against highly polymyxin-resistant P. aeruginosa and is potentially of considerable clinical utility for the treatment of problematic CF lung infections.
[Mh] Termos MeSH primário: Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos
Fibrose Cística/tratamento farmacológico
Fibrose Cística/microbiologia
Nanopartículas Metálicas/administração & dosagem
Pneumonia Bacteriana/diagnóstico por imagem
Polimixina B/administração & dosagem
Prata/administração & dosagem
[Mh] Termos MeSH secundário: Administração por Inalação
Anti-Infecciosos/administração & dosagem
Anti-Infecciosos/química
Sobrevivência Celular/efeitos dos fármacos
Fibrose Cística/patologia
Difusão
Relação Dose-Resposta a Droga
Combinação de Medicamentos
Sinergismo Farmacológico
Seres Humanos
Nanopartículas Metálicas/química
Pneumonia Bacteriana/microbiologia
Polimixina B/química
Terapia Respiratória/métodos
Prata/química
Resultado do Tratamento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Infective Agents); 0 (Drug Combinations); 1404-26-8 (Polymyxin B); 3M4G523W1G (Silver)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE


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[PMID]:29384619
[Au] Autor:Zhao H; Wang YL; Peng JR; Zhang L; Qu Y; Chu BY; Dong ML; Tan LW; Qian ZY
[Ti] Título:Biodegradable Self-Assembled Micelles Based on MPEG-PTMC Copolymers: An Ideal Drug Delivery System for Vincristine.
[So] Source:J Biomed Nanotechnol;13(4):427-36, 2017 Apr.
[Is] ISSN:1550-7033
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Despite advantageous properties, micelles using methoxy poly(ethylene glycol)-poly(trimethylene carbonate) (MPEGPTMC) have not been widely studied. In this work, we aim to develop a novel vehicle for vincristine (VCR) based on a MPEG-PTMC micelle system. MPEG-PTMC with a series of molecular weights were synthesized and screened for the appropriate range for forming stable VCR micelles. The prepared micelles were then characterized in vitro and in vivo . VCR micelles presented high stability and ideal sustained release profile. The passive targeting effect was also enhanced compared with liposomal VCR. These results provide critical data to give the first clues regarding novel VCR micelles which exhibit potential for clinical application.
[Mh] Termos MeSH primário: Implantes Absorvíveis
Dioxanos/química
Implantes de Medicamento/química
Nanocápsulas/química
Polietilenoglicóis/química
Vincristina/administração & dosagem
Vincristina/química
[Mh] Termos MeSH secundário: Cristalização/métodos
Difusão
Composição de Medicamentos/métodos
Implantes de Medicamento/administração & dosagem
Micelas
Nanocápsulas/administração & dosagem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Dioxanes); 0 (Drug Implants); 0 (Micelles); 0 (Nanocapsules); 0 (monomethoxy poly(ethylene glycol)-block-poly(trimethylene carbonate)); 30IQX730WE (Polyethylene Glycols); 5J49Q6B70F (Vincristine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180201
[St] Status:MEDLINE


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[PMID]:29284045
[Au] Autor:Bialecki S; Kazmierczak B; Lipniacki T
[Ad] Endereço:Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland.
[Ti] Título:Polarization of concave domains by traveling wave pinning.
[So] Source:PLoS One;12(12):e0190372, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pattern formation is one of the most fundamental yet puzzling phenomena in physics and biology. We propose that traveling front pinning into concave portions of the boundary of 3-dimensional domains can serve as a generic gradient-maintaining mechanism. Such a mechanism of domain polarization arises even for scalar bistable reaction-diffusion equations, and, depending on geometry, a number of stationary fronts may be formed leading to complex spatial patterns. The main advantage of the pinning mechanism, with respect to the Turing bifurcation, is that it allows for maintaining gradients in the specific regions of the domain. By linking the instant domain shape with the spatial pattern, the mechanism can be responsible for cellular polarization and differentiation.
[Mh] Termos MeSH primário: Modelos Biológicos
[Mh] Termos MeSH secundário: Difusão
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171229
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190372


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[PMID]:27770747
[Au] Autor:Lee H
[Ad] Endereço:Department of Chemical Engineering, Dankook University, Yongin, 448-701, South Korea. Electronic address: leeh@dankook.ac.kr.
[Ti] Título:Effect of polyelectrolyte size on multilayer conformation and dynamics at different temperatures and salt concentrations.
[So] Source:J Mol Graph Model;70:246-252, 2016 11.
[Is] ISSN:1873-4243
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Polyelectrolyte bilayers, which consist of poly-l-lysine (PLL) and hyaluronic acid (HA) were simulated with lipid membranes at different temperatures and ion concentrations. Starting with the sequential deposition of PLL and HA above the membrane surface, PLL and HA become completely mixed, leading to the formation of stable bilayers. PLL/HA bilayers are thicker at higher salt concentration because of weakened electrostatic interactions between PLLs and membrane lipids, in agreement with experiments. This salt effect decreases as PLL size increases. Also, bilayers become thinner at higher temperature because of the increased surface area of membrane. In particular, regardless of temperature and salt concentration, larger PLLs induce thicker bilayers, although larger PLLs have lower diffusivities than do smaller ones. Bilayers with larger PLLs show larger vacancy (more water) inside the bilayer, indicating that larger PLLs are less densely stacked on membrane surface than do smaller ones and thus form the thicker bilayer. These findings show the lower diffusivity of larger polyelectrolytes, which supports the experimental observation regarding the restricted diffusion of large polymers, and also imply the dependence of bilayer thickness on the polymer size.
[Mh] Termos MeSH primário: Conformação Molecular
Polieletrólitos/química
Cloreto de Sódio/química
Temperatura Ambiente
[Mh] Termos MeSH secundário: Ânions
Difusão
Ácido Hialurônico/química
Bicamadas Lipídicas/química
Lipídeos/química
Simulação de Dinâmica Molecular
Fosfatidilcolinas/química
Polilisina/química
Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anions); 0 (Lipid Bilayers); 0 (Lipids); 0 (Phosphatidylcholines); 0 (Polyelectrolytes); 059QF0KO0R (Water); 25104-18-1 (Polylysine); 451W47IQ8X (Sodium Chloride); 9004-61-9 (Hyaluronic Acid); TE895536Y5 (1-palmitoyl-2-oleoylphosphatidylcholine)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161023
[St] Status:MEDLINE



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