Examinando por Materia "ELECTROPORACION"
Mostrando1 - 2 de 2
Resultados por página
Opciones de clasificación
- Artículo de Publicación PeriódicaAsymmetric patterns of small molecule transport after nanosecond and microsecond electropermeabilization(2018) Sözer, Esin B.; Pocetti, Florencia; Vernier, P. Thomas"Imaging of fluorescent small molecule transport into electropermeabilized cells reveals polarized patterns of entry, which must reflect in some way the mechanisms of the migration of these molecules across the compromised membrane barrier. In some reports, transport occurs primarily across the areas of the membrane nearest the positive electrode (anode), but in others cathode-facing entry dominates. Here we compare YO-PRO-1, propidium, and calcein uptake into U-937 cells after nanosecond (6 ns) and microsecond (220 ls) electric pulse exposures. Each of the three dyes exhibits a different pattern. Calcein shows no preference for anode- or cathode-facing entry that is detectable with our measurement system. Immediately after a microsecond pulse, YO-PRO-1 and propidium enter the cell roughly equally from the positive and negative poles, but transport through the cathode-facing side dominates in less than 1 s. After nanosecond pulse permeabilization, YO-PRO-1 and propidium enter primarily on the anode-facing side of the cell."
- Capítulo de libroLipid electropore stabilization(2017-08) Fernández, María Laura; Risk, Marcelo"The stabilization of pores can be studied by different approaches such as simulations in silico or experimental procedures in vivo or in vitro. The energy to open a pore in a lipid membrane can be delivered by different external stimuli. To disrupt the membrane and initiate the pore opening, this energy has to reach a threshold. Then, once the pore is open, the external stimulus can be modulated to maintain the pore stable in time. This chapter first describes the basics of electropermeabilization, a process also called electroporation, and the basics of molecular dynamics in electropermeabilization. The chapter then describes in detail the molecular changes that lead to the pore opening and evolution by molecular dynamics. The chapter focuses on molecular dynamics because this technique allows the study of pore stabilization at molecular level, the interpretation of the lipid and water molecule rearrangements that are behind this phenomenon, and the visualization of the pore at the scale of size and time, in the order of nanometers and nanoseconds, respectively. Finally, the chapter also describes other approaches where pores remain open or the permeabilized state remains stable for a period of time, such as continuum modeling, experiments in planar membranes, and experiments in cells. The objective of this selection is to relate the results obtained by molecular dynamics with those obtained experimentally, or by other types of modeling, aiming to connect the mechanisms of pore stabilization by molecular dynamics at different scales."