Knowing the overall solute flux and the partial fluxes expressed by every single transport layer, the membrane internal interface concentrations can separately be expressed. Both the overall transport coefcient and the driving force strongly depend, among others, on the value of the structural parameter and the water permeability. Study of the interface concentrations as ...

It is shown that Streptococcus pneumoniae possesses a Ca2+ transporter, sensitive to the amiloride derivative 2',4'-dimethylbenzamil (DMB), which is essential for grown at high Ca(2+)-concentrations, and which mediates the triggering by Ca2+ of competence for genetic transformation in the exponential phase and autolysis in the late exponential phase. DMB inhibited both Ca2+ transport and the Ca...

We have used the technique of somatic cell hybridization to study the regulation of the neutral amino acid transport system L in Chinese hamster ovary (CHO) cells. The cell line CHO-ts025C1 has a temperature-sensitive mutation in leucyl-tRNA synthetase. At the nonpermissive temperature of 39 degrees C, CHO-ts025C1 cells are unable to charge leucyl-tRNA and behave as though starved for leucine b...

In this paper, we propose a quality-of-service (QOS)guaranteed transport system (QTS), which offers various QOS’s at the transport layer for broad-band multimedia communications. The QTS, composed of a bandwidth allocator and a transport protocol module, supports three classes of applications requiring different bit rates, delay sensitivity, and loss sensitivity. The bandwidth allocator intelli...

background: leishmaniasis is a parasitic disease caused by different species of leishmania parasites with a wide range of clinical manifestations . antimonial compounds such as meglumine antimoniate (glucantime) are the first line drugs for the treatment of leishmaniasis. however, according to reports of the drug resistance of parasites, the efficacy of antimonial compounds is low. the atp-bind...

Exchange factors for ARF GTPases (ARF-GEFs) regulate vesicle trafficking in a variety of organisms. The Arabidopsis protein GNOM is a brefeldin A (BFA) sensitive ARF-GEF that is required for the proper polar localization of PIN1, a candidate transporter of the plant hormone auxin. Mutations in GNOM lead to developmental defects that resemble those caused by interfering with auxin transport. Bot...

Cellular sodium transport via the Na+, K+-ATPase contributes significantly to daily energy expenditure. The effect of a meal on leucocyte Na+ transport and intracellular electrolytes was therefore investigated in lean normal subjects at room temperatures of 23 degrees and 33 degrees, to determine if the Na pump responds to the need for thermogenesis. In the fasting state, the ouabain-sensitive ...

Studies of ion transport pathophysiology in hematological disorders and tests of possible new therapeutic agents for these disorders have been carried out in various mouse models because of close functional similarities between mouse and human red cells. We have explored strain-specific differences in erythrocyte membrane physiology in 10 inbred mouse strains by determining erythrocyte contents...

Mechanisms of copper transport into purified mitochondrial suspensions prepared from the hepatopancreas of the Atlantic lobster Homarus americanus were investigated. Mitochondria were purified by combining methods of differential and Percoll-gradient centrifugation, and copper transport was studied using the copper-sensitive fluorescent dye Phen Green. Copper transport by this mitochondrial pre...