The membrane density of L-type voltage-sensitive Ca(2+) channels (L-VSCCs) of rat hippocampal neurons increases over age [days in vitro (DIV)] in long-term primary cultures, apparently contributing both to spontaneous cell death and to enhanced excitotoxic vulnerability. Similar increases in L-VSCCs occur during brain aging in vivo in rat and rabbit hippocampal neurons. However, unraveling both...

Through an assembly of interacting GPCRs, heterodimers and high-order heteromers (termed receptor mosaics) are formed and lead to changes in the agonist recognition, signaling, and trafficking of participating receptors via allosteric mechanisms, sometimes involving the appearance of cooperativity. This field has now become a major research area, and this review deals with their physiology bein...

Activation of G protein-coupled receptors (GPCRs) may bring about their disappearance from the cell membrane, and it is commonly accepted that G protein-coupled receptor kinases (GRKs) play a key function in this mechanism. Opioid receptors belong to the family of GPCRs and are substrates of GRKs. We examined the fate of and -opioid receptors and GRK2 and 3 in living cells during the process of...

Staphylococcal enterotoxins are exotoxins produced by Staphylococcus aureus that possess emetic and superantigenic properties. Prior to this research there were six characterized enterotoxins, staphylococcal enterotoxin types A to E and H (referred to as SEA to SEE and SEH). Two new staphylococcal enterotoxin genes have been identified and designated seg and sei (staphylococcal enterotoxin type...

In M/G/1 retrial queueing system with two types of customers and feedback, we derived the joint generating function of the number of customers in two groups by using the supplementary variable method. It is shown that our results are consistent with those already known in the literature when δk = 0(k = 1, 2), λ1 = 0 or λ2 = 0.

A molecule of rabbit yG-globulin’ evidently consists of four polypeptide chains held together by interchain disulfide bonds and noncovalent interactions. Each molecule comprises a pair of similar or identical “light” chains having an approximate molecular weight of 20,000, and another pair of “heavy” chains of weight 50,000 to 55,000 (2-7). Each light chain is linked to a heavy chain and the tw...

Activation of G protein-coupled receptors (GPCRs) may bring about their disappearance from the cell membrane, and it is commonly accepted that G protein-coupled receptor kinases (GRKs) play a key function in this mechanism. Opioid receptors belong to the family of GPCRs and are substrates of GRKs. We examined the fate of delta- and mu-opioid receptors and GRK2 and 3 in living cells during the p...

Using a combination of different oligonucleotides and restriction enzymes we have examined the gross organisation of repeats within the most distal region of human chromosomes. We demonstrate here that human telomeres do not contain a pure uniform 6 base pair repeat unit but that there are at least three types of repeat. These three types of repeat are present at the ends of most or all human c...

In this paper we study polynomial and geometric (exponential) ergodicity forM/G/1-type Markov chains and Markov processes. First, practical criteria for M/G/1-type Markov chains are obtained by analyzing the generating function of the first return probability to level 0. Then the corresponding criteria for M/G/1-type Markov processes are given, using their h-approximation chains. Our method yie...