Light-responsive artificial ion channels are created using self-organized TiO(2) nanotubular arrays, whose ion transport properties can be regulated by external ultraviolet light. The formation of electrostatic traps within TiO(2) nanotubes by UV light contributes to the light-regulated ion transport.

In this tutorial review, recent developments in modeling and experimental studies on nanofludics were reported. Nanofluidic studies were categorized into two groups depending on the characteristic length scale. When the size of the nanochannels and pores is 5-100 nm, electrostatic interactions are dominant, and ion and fluid flow can be analyzed by continuum dynamics. Various nanofluidic device...

The addition of actively transported sugars to the solution bathing the mucosal surface of an in vitro preparation of distal rabbit ileum results in a rapid increase in the transmural potential difference, the short-circuit current, and the rate of active Na transport from mucosa to scrosa. These effects arc dependent upon the active transport of the sugar per se and arc independent of the meta...

Point mutations in WNK4 [for With No K (lysine)], a serine-threonine kinase that is expressed in the distal nephron of the kidney, are linked to familial hyperkalemic hypertension (FHH). The imbalanced electrolyte homeostasis in FHH has led to studies toward an understanding of WNK4-mediated regulation of ion transport proteins in the kidney. A growing number of ion transport proteins for Na(+)...

The passive binding of cations to submitochondrial fragments prepared by sonic oscillation of bovine heart mitochondria has been examined. At least two different types of binding sites can be distinguished. The first site appears to be phospholipid in nature and binds the following cations in the sequence indicated: La3+ > Ca2+ > Mg2+ > K+ and Na+. Each of these cations inhibits the binding of ...

The in vitro preparation of the small intestine of the rat is well suited for studies of ion transport. Data from this preparation indicate that the passage of water and electro-lytes across the intestinal epithelium depends on active transport. Glycolysis seems to be involved as a source of energy for the transport of ions from the mucosal to the serosal aspect of the intestinal wall. LITERATU...

The concentrations of K, Na, and CI in the cytoplasm and vacuole, the tracer fluxes of these ions into and out of the cenocyte, and the electrical potential difference between bathing solution and vacuole and cytoplasm, have been measured in Hydrodictyon africanum. If the ions were acted on solely by passive electrochemical forces, a net efflux of K and CI and a net influx of Na would be expect...

The distribution and rates of exchange of the ions sodium, potassium, and chloride in single internodal cells of the ecorticate characean, Nitellopsis obtusa, have been studied. In tracer experiments three kinetic compartments were found, the outermost "free space" of the cell, a compartment we have called "protoplasmic non-free space", and the cell sap. The concentrations in the vacuole were 5...