al. Comparison of two strategies for administering nevirapine to prevent perinatal HIV transmission in high-prevalence, resource-poor settings. Simultaneous quantitative assay of six HIV protease inhibitors, one metab-olite, and two non-nucleoside reverse transcriptase inhibitors in human plasma by isocratic reversed-phase liquid chromatography. High-performance liquid chromatographic assay to ...

The ras family consists of three evolutionarily conserved genes, H-ras, N-ras, and K-ras. The ras genes code for 21-kDa proteins that mediate signal transduction between cell surface receptors and intracellular regulatory molecules. The proteins attach to the inner surface of the cytoplasmic membrane via a posttranslationally added farnesyl group. This lipid modification is essential for functi...

Introduction: The aim of this study was to evaluate the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV) in patients with recurrent aphthous stomatitis (RAS).   Materials and Methods: Eighty patients who were diagnosed with RAS between January 2014 and January 2016 were included in this study. Eighty age- and gender-matched healthy subject...

The three mammalian ras proteins associate specifically with the plasma membrane and this is essential for their biological activity. Two signals encoded within the extreme COOH terminus of the proteins specify this cellular localization; a CAAX box in combination with either a polybasic domain (p21K-~B) or a palmitoylation site (p21 m-~ and p21N-~). All members of the ras-like and rho-like sub...

The Gram-negative bacterium Myxococcus xanthus glides on solid surfaces and periodically reverses the direction of movement. Work published in this issue of The EMBO Journal (Leonardy et al, 2010) reports on the small GTPase MglA that ensures the correct polarity of the motility engines through its GTP/GDP cycle in conjunction with its cognate GAP, MglB. MglA has also been shown to interact wit...

Ras GTPases include the isoforms H-Ras, K-Ras, and N-Ras. Despite their great biochemical and biological similarities, evidence is mounting suggesting that Ras proteins may not be functionally redundant. A widespread strategy for studying small GTPases is the utilization of dominant inhibitory mutants that specifically block the activation of their respective wild-type proteins. As such, H-Ras ...

R-Ras promotes cell adhesion and activation of integrins through a process that is yet unknown. We show here that active R-Ras (38V) promotes the formation of focal adhesions and a spread cell shape. By contrast, the dominant-negative mutant of R-Ras (43N) reduces the number of focal adhesions, leading to the formation of refractile cells. In adherent cells wild-type R-Ras, activated (38V) R-Ra...