Heat strain in chemical protective clothing is an important factor in industrial and military practice. Various improvements to the clothing to alleviate strain while maintaining protection have been attempted. More recently, selectively permeable membranes have been introduced to improve protection, but questions are raised regarding their effect on heat strain. In this paper the use of select...

Polymer membranes used in separation applications exhibit a tradeoff between permeability and selectivity. That is, that are highly permeable tend to have low selectivity vice versa. For ion-exchange such as electrodialysis reverse electrodialysis, this is expressed terms of membrane permselectivity (i.e., ability selectively permeate counter-ions over co-ions) ionic conductivity transport ions...

Amphotericin B (AmB) exerts its antifungal activity by forming ion-permeable assemblies across lipid bilayers. To investigate AmB-AmB bimolecular interactions in the assembly, we carried out (13)C{(19)F}REDOR experiments using 14-(19)F- and (13)C41-labeled AmBs in sterol-containing and sterol-free palmitoyloleoylphosphatidylcholine (POPC) membranes and measured the average distance between the ...

The fine structures of nuclear envelopes known to have different permeability properties were compared. Membranes of salivary gland cell nuclei of Drosophila (third instar) and Chironomus (prepupae), which are strong barriers to ion diffusion, and membranes of oocyte nuclei (germinal vesicle) of Xenopus and Triturus, which are much more ion-permeable, show no essential difference in size, frequ...

KcsA is a tetrameric K(+) channel that is activated by acidic pH. Under open conditions of the helix bundle crossing, the selectivity filter undergoes an equilibrium between permeable and impermeable conformations. Here we report that the population of the permeable conformation (p(perm)) positively correlates with the tetrameric stability and that the population in reconstituted high density l...

Biological ion channels in membranes are selectively permeable to specific ionic species. They maintain the resting membrane potential, generate propagated action potentials, and control a wide variety of cell functions. Here it is demonstrated theoretically that boron nitride nanotubes have the ability to carry out some of the important functions of biological ion channels. Boron nitride nanot...

The protective effect of stable nitroxide radicals against oxidative damage was studied using cardiomyocyte cultures obtained from newborn rats. Monolayered cardiomyocytes were exposed to H2O2 and the effect on spontaneous beating and leakage of LDH was determined. Hydrogen peroxide irreversibly blocked rhythmic beating and resulted in a significant membrane injury as shown by release of LDH. T...

Regulatory T cells (T(reg)) are believed to suppress conventional T cell (T(conv)) proliferation in vitro in a contact-dependent, cytokine-independent manner, based in part on experiments in which T(reg) and T(conv) are separated by a permeable membrane. We show that the production of IL-35, a novel inhibitory cytokine expressed by natural T(reg), increases substantially following contact with ...

The permeability of the midgut of the fleshfly, Sarcophagafalculata, to the orally toxic polypeptide (Mr~7000), a cobra venom-cardiotoxin, was investigated by LM and EM autoradiography, using the radio-iodinated toxin. The histology of the normal and toxin affected midgut was also investigated. 1. The midgut could be classified into segments that were permeable, partially-permeable and non-perm...

Calcium-permeable channels with a slope conductance of 9 pS were revealed in excised inside-out patches of cultured HeLa cells. Over a potential range from -80 to -10 mV, unitary inward currents were recorded with 110 Ca2+ in the pipette in artificial "intracellular" solutions containing impermeant anions. Channel activity was not considerably affected by varying free calcium concentration betw...