Base de dados : MEDLINE
Pesquisa : G01.202.750 [Categoria DeCS]
Referências encontradas : 57 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 6 ir para página                

  1 / 57 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29235590
[Au] Autor:Niether D; Di Lecce S; Bresme F; Wiegand S
[Ad] Endereço:ICS-3 Soft Condensed Matter, Forschungszentrum Jülich GmbH, D-52428 Jülich, Germany. s.wiegand@fz-juelich.de.
[Ti] Título:Unravelling the hydrophobicity of urea in water using thermodiffusion: implications for protein denaturation.
[So] Source:Phys Chem Chem Phys;20(2):1012-1020, 2018 Jan 03.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Urea is widely used as a protein denaturant in aqueous solutions. Experimental and computer simulation studies have shown that it dissolves in water almost ideally at high concentrations, introducing little disruption in the water hydrogen bonded structure. However, at concentrations of the order of 5 M or higher, urea induces denaturation in a wide range of proteins. The origin of this behaviour is not completely understood, but it is believed to stem from a balance between urea-protein and urea-water interactions, with urea becoming possibly hydrophobic at a specific concentration range. The small changes observed in the water structure make it difficult to connect the denaturation effects to the solvation properties. Here we show that the exquisite sensitivity of thermodiffusion to solute-water interactions allows the identification of the onset of hydrophobicity of urea-water mixtures. The hydrophobic behaviour is reflected in a sign reversal of the temperature dependent slope of the Soret coefficient, which is observed, both in experiments and non-equilibrium computer simulations at ∼5 M concentration of urea in water. This concentration regime corresponds to the one where abrupt changes in the denaturation of proteins are commonly observed. We show that the onset of hydrophobicity is intrinsically connected to the urea-water interactions. Our results allow us to identify correlations between the Soret coefficient and the partition coefficient, log P, hence establishing the thermodiffusion technique as a powerful approach to study hydrophobicity.
[Mh] Termos MeSH primário: Desnaturação Proteica
Ureia/química
Água/química
[Mh] Termos MeSH secundário: Simulação por Computador
Interações Hidrofóbicas e Hidrofílicas
Temperatura Ambiente
Difusão Térmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
059QF0KO0R (Water); 8W8T17847W (Urea)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180209
[Lr] Data última revisão:
180209
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp05843h


  2 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:27510743
[Au] Autor:Boukari F; Makrogiannis S
[Ad] Endereço:Department of Physics and Engineering, Delaware State Univ., 1200 N. DuPont Hwy, Dover, 19901, DE, USA.
[Ti] Título:Joint level-set and spatio-temporal motion detection for cell segmentation.
[So] Source:BMC Med Genomics;9 Suppl 2:49, 2016 Aug 10.
[Is] ISSN:1755-8794
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Cell segmentation is a critical step for quantification and monitoring of cell cycle progression, cell migration, and growth control to investigate cellular immune response, embryonic development, tumorigenesis, and drug effects on live cells in time-lapse microscopy images. METHODS: In this study, we propose a joint spatio-temporal diffusion and region-based level-set optimization approach for moving cell segmentation. Moving regions are initially detected in each set of three consecutive sequence images by numerically solving a system of coupled spatio-temporal partial differential equations. In order to standardize intensities of each frame, we apply a histogram transformation approach to match the pixel intensities of each processed frame with an intensity distribution model learned from all frames of the sequence during the training stage. After the spatio-temporal diffusion stage is completed, we compute the edge map by nonparametric density estimation using Parzen kernels. This process is followed by watershed-based segmentation and moving cell detection. We use this result as an initial level-set function to evolve the cell boundaries, refine the delineation, and optimize the final segmentation result. RESULTS: We applied this method to several datasets of fluorescence microscopy images with varying levels of difficulty with respect to cell density, resolution, contrast, and signal-to-noise ratio. We compared the results with those produced by Chan and Vese segmentation, a temporally linked level-set technique, and nonlinear diffusion-based segmentation. We validated all segmentation techniques against reference masks provided by the international Cell Tracking Challenge consortium. The proposed approach delineated cells with an average Dice similarity coefficient of 89 % over a variety of simulated and real fluorescent image sequences. It yielded average improvements of 11 % in segmentation accuracy compared to both strictly spatial and temporally linked Chan-Vese techniques, and 4 % compared to the nonlinear spatio-temporal diffusion method. CONCLUSIONS: Despite the wide variation in cell shape, density, mitotic events, and image quality among the datasets, our proposed method produced promising segmentation results. These results indicate the efficiency and robustness of this method especially for mitotic events and low SNR imaging, enabling the application of subsequent quantification tasks.
[Mh] Termos MeSH primário: Técnicas Citológicas
Movimento (Física)
[Mh] Termos MeSH secundário: Algoritmos
Ciclo Celular
Movimento Celular
Separação Celular
Diagnóstico por Imagem
Células HeLa
Seres Humanos
Microscopia de Fluorescência
Modelos Biológicos
Difusão Térmica
Imagem com Lapso de Tempo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160812
[St] Status:MEDLINE
[do] DOI:10.1186/s12920-016-0206-5


  3 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27384914
[Au] Autor:Kondo A; Nishizawa Y; Ito M; Saito N; Fujii S; Akamoto S; Fujiwara M; Okano K; Suzuki Y
[Ad] Endereço:Department of Gastroenterological Surgery, Faculty of Medicine, Kagawa University, Kagawa, Japan.
[Ti] Título:Relationship between tissue tension and thermal diffusion to peripheral tissue using an energy device.
[So] Source:Asian J Endosc Surg;9(3):226-30, 2016 Aug.
[Is] ISSN:1758-5910
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The aim of the study was to assess the relationship between tissue tension and thermal diffusion to peripheral tissues using an electric scalpel, ultrasonically activated device, or a bipolar sealing system. The mesentery of pigs was excised with each energy device (ED) at three tissue tensions (0, 300, 600 g). The excision time and thermal diffusion area were monitored with thermography, measured for each ED, and then histologically examined. Correlations between tissue tension and thermal diffusion area were examined. The excision time was inversely correlated with tissue tension for all ED (electric scalpel, r = 0.718; ultrasonically activated device, r = 0.949; bipolar sealing system, r = 0.843), and tissue tension was inversely correlated with the thermal diffusion area with the electric scalpel (r = 0.718) and bipolar sealing system (r = 0.869). Histopathologically, limited deep thermal denaturation occurred at a tension of 600 g with all ED. We conclude that thermal damage can be avoided with adequate tissue tension when any ED is used.
[Mh] Termos MeSH primário: Eletrocirurgia/instrumentação
Mesentério/cirurgia
Estresse Mecânico
Difusão Térmica
Procedimentos Cirúrgicos Ultrassônicos/instrumentação
[Mh] Termos MeSH secundário: Animais
Fenômenos Biomecânicos
Mesentério/patologia
Mesentério/fisiologia
Suínos
Termografia
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170327
[Lr] Data última revisão:
170327
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160708
[St] Status:MEDLINE
[do] DOI:10.1111/ases.12283


  4 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:27064575
[Au] Autor:Noroozi M; Zakaria A; Radiman S; Abdul Wahab Z
[Ad] Endereço:Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
[Ti] Título:Environmental Synthesis of Few Layers Graphene Sheets Using Ultrasonic Exfoliation with Enhanced Electrical and Thermal Properties.
[So] Source:PLoS One;11(4):e0152699, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.
[Mh] Termos MeSH primário: Grafite/química
Difusão Térmica
Ultrassom/métodos
[Mh] Termos MeSH secundário: Condutividade Elétrica
Grafite/síntese química
Microscopia Eletrônica de Varredura/métodos
Microscopia Eletrônica de Transmissão
Povidona/química
Pós/química
Sabões/química
Sonicação
Espectrofotometria Ultravioleta
Análise Espectral Raman
Água/química
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Powders); 0 (Soaps); 059QF0KO0R (Water); 7782-42-5 (Graphite); FZ989GH94E (Povidone)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160412
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0152699


  5 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27059558
[Au] Autor:Tiwary P; Berne BJ
[Ad] Endereço:Department of Chemistry, Columbia University, New York, New York 10027, USA.
[Ti] Título:Kramers turnover: From energy diffusion to spatial diffusion using metadynamics.
[So] Source:J Chem Phys;144(13):134103, 2016 Apr 07.
[Is] ISSN:1089-7690
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We consider the rate of transition for a particle between two metastable states coupled to a thermal environment for various magnitudes of the coupling strength using the recently proposed infrequent metadynamics approach [P. Tiwary and M. Parrinello, Phys. Rev. Lett. 111, 230602 (2013)]. We are interested in understanding how this approach for obtaining rate constants performs as the dynamics regime changes from energy diffusion to spatial diffusion. Reassuringly, we find that the approach works remarkably well for various coupling strengths in the strong coupling regime, and to some extent even in the weak coupling regime.
[Mh] Termos MeSH primário: Modelos Teóricos
Difusão Térmica
[Mh] Termos MeSH secundário: Fricção
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Em] Mês de entrada:1612
[Cu] Atualização por classe:170407
[Lr] Data última revisão:
170407
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160410
[St] Status:MEDLINE
[do] DOI:10.1063/1.4944577


  6 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27021655
[Au] Autor:Kredentser S; Eremin A; Davidson P; Reshetnyak V; Stannarius R; Reznikov Y
[Ad] Endereço:Institute of Physics of National Academy of Sciences of Ukraine, Pr. Nauky 46, 03028, Kyiv, Ukraine. sergeykredenser@gmail.com.
[Ti] Título:Light-induced Soret effect and adsorption of nanocrystals in organic solvents.
[So] Source:Eur Phys J E Soft Matter;39(3):38, 2016 Mar.
[Is] ISSN:1292-895X
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:A light-induced Soret effect accompanied by photoinduced adsorption of pigment nanoparticles is described in organic solvents. We report an unexpected inversion of the nanoparticle flux which is directed along the temperarture gradient at short exposures to the light and switches against the gradient at longer exposures. This change of flux direction is due to light-induced adsorption of the nanocrystals onto the substrates of the cell.
[Mh] Termos MeSH primário: Alcanos/química
Luz
Nanopartículas/química
Solventes/química
Difusão Térmica
[Mh] Termos MeSH secundário: Adsorção
Corantes
Estabilidade de Medicamentos
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Alkanes); 0 (Coloring Agents); 0 (Solvents); 11A386X1QH (n-dodecane)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:171014
[Lr] Data última revisão:
171014
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160330
[St] Status:MEDLINE
[do] DOI:10.1140/epje/i2016-16038-1


  7 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:26871127
[Au] Autor:Daddi-Moussa-Ider A; Guckenberger A; Gekle S
[Ad] Endereço:Biofluid Simulation and Modeling, Fachbereich Physik, Universität Bayreuth, Universitätsstraße 30, Bayreuth 95440, Germany.
[Ti] Título:Long-lived anomalous thermal diffusion induced by elastic cell membranes on nearby particles.
[So] Source:Phys Rev E;93(1):012612, 2016 Jan.
[Is] ISSN:2470-0053
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The physical approach of a small particle (virus, medical drug) to the cell membrane represents the crucial first step before active internalization and is governed by thermal diffusion. Using a fully analytical theory we show that the stretching and bending of the elastic membrane by the approaching particle induces a memory in the system, which leads to anomalous diffusion, even though the particle is immersed in a purely Newtonian liquid. For typical cell membranes the transient subdiffusive regime extends beyond 10 ms and can enhance residence times and possibly binding rates up to 50%. Our analytical predictions are validated by numerical simulations.
[Mh] Termos MeSH primário: Membrana Celular/metabolismo
Elasticidade
Modelos Biológicos
Difusão Térmica
[Mh] Termos MeSH secundário: Simulação por Computador
Endocitose/fisiologia
Eritrócitos/fisiologia
Seres Humanos
Pinças Ópticas
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; VALIDATION STUDIES
[Em] Mês de entrada:1608
[Cu] Atualização por classe:160213
[Lr] Data última revisão:
160213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160213
[St] Status:MEDLINE
[do] DOI:10.1103/PhysRevE.93.012612


  8 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
PubMed Central Texto completo
Texto completo
[PMID]:26863001
[Au] Autor:Chung CY; Wang JC; Chuang HS
[Ad] Endereço:Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.
[Ti] Título:Rapid Bead-Based Antimicrobial Susceptibility Testing by Optical Diffusometry.
[So] Source:PLoS One;11(2):e0148864, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study combined optical diffusometry and bead-based immunoassays to develop a novel technique for quantifying the growth of specific microorganisms and achieving rapid AST. Diffusivity rises when live bacteria attach to particles, resulting in additional energy from motile microorganisms. However, when UV-sterilized (dead) bacteria attach to particles, diffusivity declines. The experimental data are consistent with the theoretical model predicted according to the equivalent volume diameter. Using this diffusometric platform, the susceptibility of Pseudomonas aeruginosa to the antibiotic gentamicin was tested. The result suggests that the proliferation of bacteria is effectively controlled by gentamicin. This study demonstrated a sensitive (one bacterium on single particles) and time-saving (within 2 h) platform with a small sample volume (~0.5 µL) and a low initial bacteria count (50 CFU per droplet ~ 105 CFU/mL) for quantifying the growth of microorganisms depending on Brownian motion. The technique can be applied further to other bacterial strains and increase the success of treatments against infectious diseases in the near future.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Gentamicinas/farmacologia
Imunoensaio/métodos
Testes de Sensibilidade Microbiana/métodos
Pseudomonas aeruginosa/efeitos dos fármacos
[Mh] Termos MeSH secundário: Carga Bacteriana
Divisão Celular
Resistência a Medicamentos
Microscopia Eletrônica de Varredura
Microscopia de Fluorescência
Microesferas
Movimento (Física)
Tamanho da Partícula
Pseudomonas aeruginosa/crescimento & desenvolvimento
Pseudomonas aeruginosa/fisiologia
Difusão Térmica
Fatores de Tempo
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Gentamicins)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160211
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0148864


  9 / 57 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:26566109
[Au] Autor:Hamid D; Casnedi S
[Ad] Endereço:AGYL, 86, avenue des Vosges, 67000 Strasbourg, France. Electronic address: D-hamid@live.fr.
[Ti] Título:[Tissue effect of Greenlight(®) laser on uterine fibroids].
[Ti] Título:Évaluation des effets tissulaires du laser Greenlight(®) pour la prise en charge des fibromes utérins..
[So] Source:J Gynecol Obstet Biol Reprod (Paris);45(2):124-8, 2016 Feb.
[Is] ISSN:1773-0430
[Cp] País de publicação:France
[La] Idioma:fre
[Ab] Resumo:OBJECTIVE: We evaluated the efficacy and the safety parameters for Greenlight(®) laser to vaporise myoma. MATERIALS AND METHODS: We studied 6 utero after hysterectomies for myoma and used the Greenlight(®) laser with different level of power and duration on myoma and normal myometer. We compared the tissue effect with the monopolar and bipolar resection. We studied the tissue effect by histological exam. RESULTS: The Greenlight(®) laser is able to vaporize myoma with a low side effect on normal myometer of 85µm (199µm with bipolar and 254µm with monopolar). CONCLUSION: The laser Greenlight(®) is efficient to vaporize myoma in vitro and presents some safety parameter. This study could lead to a clinical prospective study to demonstrate its ability to treat symptomatic myoma.
[Mh] Termos MeSH primário: Terapia a Laser/efeitos adversos
Leiomioma/cirurgia
Neoplasias Uterinas/cirurgia
[Mh] Termos MeSH secundário: Adulto
Endométrio/patologia
Feminino
Seres Humanos
Histerectomia/efeitos adversos
Histerectomia/métodos
Leiomioma/patologia
Meia-Idade
Órgãos em Risco/patologia
Complicações Pós-Operatórias/etiologia
Difusão Térmica
Resultado do Tratamento
Neoplasias Uterinas/patologia
[Pt] Tipo de publicação:CLINICAL TRIAL; JOURNAL ARTICLE
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151114
[St] Status:MEDLINE


  10 / 57 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:26530465
[Au] Autor:Das PK
[Ad] Endereço:Global R&D Tata Steel, Jamshedpur, India.
[Ti] Título:Effect of thermodiffusion on pH-regulated surface charge properties of nanoparticle.
[So] Source:Electrophoresis;37(2):347-55, 2016 Jan.
[Is] ISSN:1522-2683
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Surface properties of nanoparticle are of high importance in the field of biotechnology, drug delivery and micro/nanofabrication. In this article, we developed a comprehensive theoretical model and subsequently solved that numerically to study the effect of thermodiffusion of ions on surface charge properties of nanoparticle. The theoretical study has been done considering silica nanoparticle for two aqueous solutions NaCl and KCl. The effect of solution pH in conjunction with nanoparticle temperature on surface charge density has been obtained for different salt concentrations (1, 10 and 100 mM) and nanoparticle size (diameter of 2 and 100 nm). It is observed from the results that with increasing temperature of the nanoparticle, the negative surface charge density gets higher due to increasing thermodiffusion effect. It is also found out that the magnitude of surface charge density is higher for KCl solution than NaCl solution under same condition which is attributed mostly due to less thermodiffusion of counterions for KCl than NaCl. Present study also shows that magnitude of surface charge density decreases with increasing nanoparticle size until it reaches a limiting value (called critical size) above which the effect of nanoparticle size on surface charge density is insignificant.
[Mh] Termos MeSH primário: Nanopartículas/química
Dióxido de Silício/química
Eletricidade Estática
Difusão Térmica
[Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio
Cloreto de Potássio/química
Cloreto de Sódio/química
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
451W47IQ8X (Sodium Chloride); 660YQ98I10 (Potassium Chloride); 7631-86-9 (Silicon Dioxide)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151105
[St] Status:MEDLINE
[do] DOI:10.1002/elps.201500374



página 1 de 6 ir para página                
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde