The rate of Ca influx into ghosts containing arsenazo III changes with time, being most rapid during the first 5 min after Ca is added to the outside and declining thereafter. The rate of Ca influx is a nonlinear function ofextracellular Ca and plateaus as the latter is increased above 1 mM. The rate of Ca influx was measured as a function of the transmembrane gradients of Na and K and changes ...

Scanning electrochemical microscopy (SECM) is a powerful technique that can provide chemical identity, quantification, and spatiotemporal information on biosurfaces. The ability of SECM for noninvasive high-resolution imaging has made it valuable the study cell phenotypes functions. This review focuses latest advances biosurface imaging. measurements different biomarkers, including oxygen consu...

The novel oriented electrospun nanofiber membrane composed of MOFs and SPPESK has been synthesized for proton exchange membrane fuel cell operating at high temperature and anhydrous conditions. It is clear that the oriented nanofiber membrane displays the higher proton conductivity than that of the disordered nanofiber membrane or the membrane prepared by conventional solvent-casting method (wi...

The transport of sterols incorporated into the lecithin bilayer of small unilamellar liposomes through a model membrane was studied. A two-chamber diffusion cell containing liposomes with incorporated [4-14C)cholesterol or beta-[4-14C]sitosterol in the donor chamber and liposomes with unlabeled cholesterol in the receiver chamber was used. The permeability coefficients of the sterols through si...

The role of zinc (Zn) in enhancing defense capacity of several plants against salinity has been demonstrated but there is limited information on the impact of Zn nutrition on alleviating salinity-induced oxidative damage in olive. One-year-old seedlings of two varieties of olive (Olea europaea L. cvs. Frontoio and Conservolea) supplied with three Zn levels (0, 1 and 5 mM in the form of ZnSO4.7H...

Although water, small nonelectrolytes, and gases are freely permeable through most biological membranes, apical membranes of certain barrier epithelia exhibit extremely low permeabilities to these substances. The role of integral membrane proteins in this barrier function has been unclear. To study this problem, we have ablated the mouse gene encoding uroplakin III (UPIII), one of the major pro...

UNLABELLED Two different analytical methods were evaluated for their capacity to provide quantitative information on onion cell membrane permeability and integrity after high pressure and thermal processing and to study the impact of these processing treatments on cell compartmentalization and texture quality. To determine changes in cell membrane permeability and/or integrity the methodologies...

It is possible to develop a method of analyzing membrane pore sizes based on quite different principles from those so elegantly described by Dr. Solomon in this Symposium. This depends upon an assumption that ions in aqueous solution will not penetrate through a membrane with pores of less than I o A in radius unless the size of the ion and the size of the pore are almost equal (1). Such a situ...

Mitochondria possess a semipermeable membrane with properties similar to the cell membrane. Despite the presence of a limiting membrane, mitochondria swell approximately 4 to 5 times their original volume without lysis or loss of internal solute. For this reason, it has been argued that the membrane might be convoluted. The present kinetic study of the permeability of isolated mitochondria was ...