The blockade of CLC-0 chloride channels by p-chlorophenoxy acetate (CPA) has been thought to be state dependent; the conformational change of the channel pore during the "fast gating" alters the CPA binding affinity. Here, we examine the mechanism of CPA blocking in pore-open mutants of CLC-0 in which the residue E166 was replaced by various amino acids. We find that the CPA-blocking affinities...

In this study, neat HDPE and HDPE/PE-g-MA/EVA blend membranes were fabricated via thermally induced phase separation (TIPS) method and their fouling behaviors were examined using filtration of BSA protein. Membranes were characterized using FESEM, AFM, ATR-FTIR analyses and porosity measurement. Fouling behavior of membranes was analyzed using the resistance-in-series (RIS), classic and combine...

Inward rectification induced by mono- and diaminoalkane application to inside-out membrane patches was studied in Kir2.1 (IRK1) channels expressed in Xenopus oocytes. Both monoamines and diamines block Kir2.1 channels, with potency increasing as the alkyl chain length increases (from 2 to 12 methylene groups), indicating a strong hydrophobic interaction with the blocking site. For diamines, but...

Inward rectifier K(+) channels (Kir2.1) exhibit an extraordinary rectifying feature in the current-voltage relationship. We have previously showed that the bundle-crossing region of the transmembrane domain constitutes the crucial segment responsible for the polyamine block. In this study, we demonstrated that the major blocking effect of intracellular Mg(2+) on Kir2.1 channels is also closely ...

Tetrodotoxin-resistant (TTX-R) Na(+) channels are much less susceptible to external TTX but more susceptible to external Cd(2+) block than tetrodotoxin-sensitive (TTX-S) Na(+) channels. Both TTX and Cd(2+) seem to block the channel near the "DEKA" ring, which is probably part of a multi-ion single-file region adjacent to the external pore mouth and is involved in the selectivity filter of the c...

For solid–liquid separation, filter meshes are still used across large areas today, as they offer a cost-effective alternative, for example, compared to membranes. However, particle interaction leads continuous blocking of the pores, which lowers flow rate mesh and reduces its lifetime. This can be remedied by aids. In precoat filtration, these provide an already fully formed cake on fabric, ac...

in this work, sio2 –zro2 mixed oxides was prepared by the polymeric sol–gel route. the characterization of pore structure, which determines the permeation process of membrane, is of great importance. so far, most investigations have focused on such pore structure as specific surface area and pore size distribution, but the surface fractal, the important parameter reflecting the roughness of por...

Using a special double-layer membrane to avoid interaction among flow fields generated by different pores, we have, for the first time, observed the predicted discontinuous first-order transition in ultrafiltration of flexible linear polymer chains. Namely, the chain could pass through a pore much smaller than its unperturbed radius only when the flow rate is higher than a certain value. When o...