recurrent aphthous stomatitis (ras) is known as the most common chronic disease of the oral cavity, which affects a range of 5-25% of the population. ras appears to be associated with some human leukocyte antigen (hla) class ii alleles and haplotypes. this study attempts to survey the distribution of hla-drb and -dqb alleles among iranian ras patients and healthy controls. in order to evaluate ...

Small GTP-binding proteins (G-proteins) exist in eukaryotes from yeast to human and constitute a superfamily consisting of more than 100 members. This superfamily is structurally classified into at least five families: the Ras, Rho/Rac/Cdc42, Rab, Sar1/ Arf, and Ran families. They play key roles not only in temporal but also in spatial determination of specific cell functions. It has become cle...

Angiotensin (Ang) II is capable of producing inflammatory changes by signals through its AT1 receptor. Reactive oxygen species production, adhesion molecule expression, chemokines, and other mediators are involved. Nuclear factor-kappaB (NK-kappaB) and activator protein 1 (AP-1) are two of the transcription factors activating the responsible genes. We have studied Ang II-independent modulating ...

Fluid shear stress caused by blood flow is a major determinant of vascular remodeling and arterial tone and can lead to development of atherosclerosis. The endothelial monolayer in vivo acts as a signal transduction interface for hemodynamic forces; these forces determine the shape, cytoskeletal organization, and function of endothelial cells, allowing the vessels to cope with physiological or ...

0962-8924/00/$ – see front matter © 2000 Elsevier Science Ltd. All rights reserved. 85 PII: S0962-8924(99)01710-9 The Ras superfamily of small GTPases contains over 80 members. Although the function of many of these remains obscure, they can be grouped into six broad subfamilies – Ras, Ran, Rad, Rab, Arf and Rho – according to a combination of protein homology and function. Proteins in each sub...

Ypt/Rab proteins constitute the largest subfamily of the Ras superfamily of monomeric GTPases and are regulators of vesicular protein transport. Their slow intrinsic GTPase activity (10(-4)-10(-3) min(-1) at 30 degrees C) has to be accelerated to switch the active to the inactive conformation. We have identified the catalytic domain within the C-terminal halves of two yeast GTPase-activating pr...