Biomembranes
Mostrando 13-24 de 46 artigos, teses e dissertações.
-
13. Avaliação da solubilização de membranas eritrocitarias e suas proteinas por novos surfantantes zwiterionicos
The choice of a surfactant is one of the most important steps for lipid and membrane proteins solubilization. A detailed knowledge of the surfactant properties is very useful for its application into membrane studies. In this work, we determined physicochemical properties of two novel zwitterionic amidosulfobetaine surfactants, ASB14 and ASB-16, and their so
Publicado em: 2004
-
14. EPR studies of the enzyme chlorocatechol 1,2-dioxygenase and of the dynamic structure of biomembranes / Estudos da enzima clorocatecol 1,2-dioxigenase por EPR convencional e da estrutura dinâmica de biomembranas por EPR pulsada bidimensional
Neste trabalho, usamos a técnica de Ressonância Paramagnética Eletrônica em seu modo convencional para o estudo da enzima clorocatecol 1,2-dioxigenase e em seu modo pulsado para o estudo da estrutura dinâmica de biomembranas. Clorocatecol 1,2-dioxigenase é uma enzima que catalisa a clivagem de estruturas aromáticas, como a do clorocatecol, via a a ati
Publicado em: 2001
-
15. ANÁLISIS NUMÉRICA DE MEMBRANAS Y BIOMEMBRANAS VISCOELÁSTICAS SUBMETIDAS A EXPANSIÓN ASIMÉTRICA / ANÁLISE NUMÉRICA DE MEMBRANAS E BIOMEMBRANAS VISCOELÁSTICAS SUBMETIDAS À EXPANSÃO AXISSIMÉTRICA / NUMERICAL ANALYSIS OF VISCOELASTIC MEMBRANES AND BIOMEMBRANES SUBJECTED TO AXIALLY-SYMMETRIC EXPANSION
Tissue expansion is a well-known plastic surgery technique, based on the ability of biologic membranes to increase its surface area when a deformation is imposed. It is used to repair a wound area (scars, burns), to remove tattoos, in breast reconstruction, etc. This involves inserting a silicon-rubber prosthesis (expander) in its collapsed state under the s
Publicado em: 1999
-
16. Commentary: surface tension of biomembranes.
-
17. On soliton propagation in biomembranes and nerves
The lipids of biological membranes and intact biomembranes display chain melting transitions close to temperatures of physiological interest. During this transition the heat capacity, volume and area compressibilities, and relaxation times all reach maxima. Compressibilities are thus nonlinear functions of temperature and pressure in the vicinity of the melt
National Academy of Sciences.
-
18. Intrinsic curvature hypothesis for biomembrane lipid composition: a role for nonbilayer lipids.
A rationale is presented for the mix of "bilayer" and "nonbilayer" lipids, which occurs in biomembranes. A theory for the L alpha-HII phase transition and experimental tests of the theory are reviewed. It is suggested that the phase behavior is largely the result of a competition between the tendency for certain lipid monolayers to curl and the hydrocarbon p
-
19. Proton-Enhanced 13C Nuclear Magnetic Resonance of Lipids and Biomembranes
A recently developed nuclear double resonance technique which permits sensitive detection, together with high resolution, of rare spins in solids or other dipolar-coupled nuclear systems [Pines, Gibby, and Waugh (1973) J. Chem. Phys. 59, 569] has been applied to the study of natural abundance 13C-nuclear magnetic resonance in lipid mesophases and of selectiv
-
20. Monitoring Biophysical Properties of Lipid Membranes by Environment-Sensitive Fluorescent Probes
We review the main trends in the development of fluorescence probes to obtain information about the structure, dynamics, and interactions in biomembranes. These probes are efficient for studying the microscopic analogs of viscosity, polarity, and hydration, as well as the molecular order, environment relaxation, and electrostatic potentials at the sites of t
The Biophysical Society.
-
21. Molecular mechanisms for proton transport in membranes.
Likely mechanisms for proton transport through biomembranes are explored. The fundamental structural element is assumed to be continuous chains of hydrogen bonds formed from the protein side groups, and a molecular example is presented. From studies in ice, such chains are predicted to have low impedance and can function as proton wires. In addition, conform
-
22. Understanding nature's design for a nanosyringe
Synthetic and natural peptide assemblies can possess transport or conductance activity across biomembranes through the formation of nanopores. The fundamental mechanisms of membrane insertion necessary for antimicrobial or synthetic pore formation are poorly understood. We observe a lipid-assisted mechanism for passive insertion into a model membrane from mo
National Academy of Sciences.
-
23. Spontaneous formation of interfacial lipid-protein monolayers during adsorption from vesicles.
Spread and adsorbed monolayers of lipid-protein mixtures have served as models for biomembranes and pulmonary surfactant, but their similarity was unclear. Epifluorescence microscopy of monolayers spontaneously adsorbed from vesicles of dipalmitoylphosphatidylcholine or dipalmitoylphosphatidylcholine plus surfactant protein C (SP-C) showed gas, liquid expand
-
24. Dynamics of pore growth in membranes and membrane stability.
Pores can form and grow in biomembranes because of factors such as thermal fluctuation, transmembrane electrical potential, and cellular environment. We propose a new statistical physics model of the pore growth treated as a non-Markovian stochastic process, with a free energy barrier and memory friction from the membrane matrix treated as a quasi-two-dimens