Neonatal beta-adrenoceptors (beta-ARs) are resistant to agonist-induced desensitization. We examined the functioning of G(i) and G(s) after repeated administration of beta-AR agonists to newborn rats. Isoproterenol (beta(1)/beta(2) agonist) obtunded G(i) function in the heart but not the liver; in contrast, terbutaline, a beta(2)-selective agonist, enhanced G(i) function. Isoproterenol, but not...

The location of membrane-associated proteins of vesicular stomatitis virus was investigated by using two monofunctional and three bifunctional probes that differ in the degree to which they partition into membranes and in their specific group reactivity. Two hydrophobic aryl azide probes, [(125)I]5-iodonaphthyl-1-azide and [(3)H]pyrenesulfonylazide, readily partitioned into virion membrane and,...

There is increasing evidence that a class of cell membrane glycolipids, gangliosides, can mediate the fibrillogenesis and toxicity of Alzheimer's disease amyloid-beta peptide (Abeta). Using lipid monolayers and vesicles as model membranes, we measured the insertion of Abeta into 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-ganglioside GM1 monolayers to probe Abeta-GM1 interactions, imaged...

During the course of studies on the morphological changes that occur in rat liver mitochondria during certain ion movements (1), it was found that some extremely large structures formed when mitochon-dria were incubated in a reaction mixture that contained glutamate, phosphate, EDTA, and su-crose. Since the initial electron microscope studies revealed the presence of an unusual membranous struc...

This study aims to explore potential clinical relevance of sHLA-G to premature rupture of membrane. 75 samples of pregnancy were enrolled, including patients with preterm premature rupture of membranes (PPROM), patients with term premature rupture of membranes (TPROM) and normal pregnancy women. Level of sHLA-G in multiple sites were examined with ELISA. Lymphocytes were isolated from periphera...

MDCK cells maintain the polarized distribution of surface proteins mainly by sorting the newly synthesized proteins in the trans-Golgi network (TGN). In order to identify the components of the putative sorting machinery and to study factors that affect the sorting process, we have developed an in vitro system that reconstitutes the transport of viral glycoproteins from the TGN to the apical or ...

Although colistin's clinical use is limited due to its nephrotoxicity, colistin is considered to be an antibiotic of last resort because it is used to treat patients infected with multidrug-resistant bacteria. In an effort to provide molecular details about colistin's ability to kill Gram-negative (G(-)) but not Gram-positive (G(+)) bacteria, we investigated the biophysics of the interaction be...

This study shows markedly different isotype distributions of antibodies to asexual blood stages of Plasmodium falciparum and to merozoite surface protein 1 in clinically immune Senegalese adults depending on the study site. The relationships between immunoglobulin M (IgM) and IgG and between IgG3 and IgG1 antibodies differed in settings where transmission is perennial compared to settings where...

Introduction: The functional effects of orexin-B on the calcium spikes and excitability of the neuronal soma membrane of garden snail, Helix aspersa were studied. Methods: Conventional intracellular recording, under the current clamp conditions was performed to examine the effects of orexin-B on the configuration and electrophysiological properties of calcium spikes. Results: Application o...

Bacterial outer membrane porins have a robust beta-barrel structure and therefore show potential for use as stochastic sensors based on single-molecule detection. The monomeric porin OmpG is especially attractive compared with multisubunit proteins because appropriate modifications of the pore can be easily achieved by mutagenesis. However, the gating of OmpG causes transient current blockades ...