Eukaryotic cell proliferation is controlled by specific growth factors and the availability of essential nutrients. If either of these signals is lacking, cells may enter into a specialized nondividing resting state, known as stationary phase or G(0). The entry into such resting states is typically accompanied by a dramatic decrease in the overall growth rate and an increased resistance to a va...

Cell-surface galactosyltransferase was studied in suspensions of intact baby hamster kidney fibroblasts with both endogenous and exogenous glycoprotein acceptors. The cell-surface location of galactosyltransferase was demonstrated in experiments with the enzyme modifier alpha-lactalbumin, which does not enter the cell. The addition of alpha-lactalbumin to the assay medium for galactosyltransfer...

Homeostatic proliferation (HSP) is a major mechanism by which long-lived naïve and memory CD4+ T cells are maintained in vivo and suggested to contribute to the persistence of the latent HIV-1 reservoir. However, while many in vitro latency models rely on CD4+ T cells that were initially differentiated via T-cell receptor (TCR) stimulation into memory/effector cells, latent infection of naïve r...

Activated NK cells lyse tumor cells and virus-infected cells and produce IFN-gamma upon contact with sensitive target cells. The regulation of these effector responses in resting NK cells is not well understood. We now describe a receptor, KIR2DL4, that has the unique property of inducing IFN-gamma production, but not cytotoxicity, by resting NK cells in the absence of cytokines. In contrast, t...

Comparisons between electrotronic potentials and certain predicted curves allow the identification of the membrane potential at which the sodium and potassium currents are switched on in frog sartorius. The activation potentials (the membrane potentials at which the ionic currents are great enough to be resolved by the method) are functions of the resting potential and time but not of ionic con...

background: secretory proteins of ige receptor activated mast cells and basophils play a pivotal role in the generation of immediate and long term immune responses in allergy and type i hypersensitivity. objective: the present study aims to generate a 2-d map and profile of proteins secreted from a high secretory variant of the rat basophilic leukemia cell line, rbl-2h3.1, which in view of the ...

The biodegradation kinetics of 4-chlorophenol (4-CP) and phenol microbial growth Pseudomonas putida (P. putida) cells were estimated in batch biofilm reactors. kinetic parameters on determined using the Haldane formula. maximum specific rate P. phenol, half-saturation constant self-inhibition 0.512 h−1, 78.38 mg/L 228.5 mg/L, respectively. yield (YP) was 0.618 mg phenol/mg cell. experimental re...

A KNOWLEDGE OF MOLECULAR BIOLOGY in health and disease has been a goal of the modern-day physician. Until recently , understanding of the electrocardio-gram has been based mostly on the sequence and duration of the myocardial activation process. The introduction of the Lmg-Gerard1 microcapillary electrode has permitted a study of the resting and action potential of an individual cell. Consequen...

BACKGROUND Decline immune function is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. Though T cell immune response was inhibited by microgravity, it is not clearly whether activation would be inhibited after a pre-exposure of microgravity on T lymphocytes at the resting state. METHODS We herein investigated the re...