Duodenal mucosal defense was assessed by measuring blood flow and epithelial intracellular pH (pHi) of rat proximal duodenum in vivo. Fluorescence microscopy was used to measure epithelial pHi using the trapped, pHi-indicating dye 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein-AM. Blood flow was measured with laser-Doppler flowmetry. The mucosa was briefly superfused with NH4Cl, pH 2.2 buffe...

Although it is beyond doubt that mammary cells accumulate iodide via a Na+-dependent transport mechanism, it is not clear if this is the only pathway for iodide transport in mammary tissue. In view of this, experiments were designed to test for the presence of an anion-exchange pathway which could mediate the transport of iodide into mammary cells; thus, the effect of external iodide on sulfate...

Sertoli cells from mammalian testis are key cells involved in the development and maintenance of stem cell spermatogonia as well as in the secretion of a Cl(-) and K(+)-rich fluid into the lumen of seminiferous tubules. The pharmacology and contribution of Cl(-) channels to the physiology of Sertoli cells were investigated using whole-cell patch clamp and iodide efflux experiments applied to cu...

The ping-pong model for the red cell anion exchange system postulates that the transport protein band 3 can exist in two different conformations, one in which the transport site faces the cytoplasm (Ei) and another in which it faces the outside medium (Eo). This model predicts that an increase in intracellular chloride should increase the fraction of sites in the outward-facing, unloaded form (...

Decision support for 24/7 enterprises requires 24/7 available Data Warehouses (DWs). In this context, web-based connections to DWs are used by business management applications demanding continuous availability. Given that DWs store highly sensitive business data, a web-based connection provides a door for outside attackers and thus, creates a main security issue. Database Intrusion Detection Sy...

BK polyomavirus (BKPyV) is a member of a family of potentially oncogenic viruses, whose reactivation can cause severe pathological conditions in transplant patients, leading to graft rejection. As with many non-enveloped viruses, it is assumed that virus release occurs through lysis of the host cell. We now show the first evidence for a non-lytic release pathway for BKPyV and that this pathway ...

Collaboration and information sharing has obliged participating parties to look for improved detection accuracy and reaction speed in Distributed Intrusion Detection Systems (DIDS) solutions. This is mainly due to the increasing number of attacks as well as increasingly sophisticated intrusions and more alarmingly various critical components of a system can be targeted. This is further exaspera...

The mechanism of adrenergic swelling and associated pH changes was investigated in avian (goose) and teleost (striped bass and rainbow trout) erythrocytes. The swelling of goose red cells was probably caused by Na/K/Cl~ cotransport and consecutive osmotic flow of water into the cell. Goose red cells swelled when exposed to isoproterenol in the presence of elevated extracellular K, but not at ph...

We have described previously a novel Ca2+-induced Ca2+-release (CICR) mechanism in permeabilized A7r5 cells (embryonic rat aorta) and 16HBE14o-cells (human bronchial mucosa) cells (J Biol Chem 278:27548-27555, 2003). This CICR mechanism was activated upon the elevation of the free cytosolic calcium concentration [Ca2+]c and was not inhibited by pharmacological inhibitors of the inositol-1,4,5-t...

Progesterone, a putative in vivo initiator of the human sperm acrosome reaction (AR), has previously been shown to act at the sperm plasma membrane to initiate the AR in vitro. Here, we have investigated whether bicarbonate (HCO3-) was required for the progesterone-initiated human AR and whether HCO3(-)-dependent cAMP activation might be involved. Capacitated human sperm were suspended in the p...