نتایج جستجو برای: vaca protein
تعداد نتایج: 1235901 فیلتر نتایج به سال:
PURPOSE Helicobacter pylori causes gastric damage and is involved in gastric carcinogenesis. Vascular endothelial growth factor (VEGF) plays a major role in gastric mucosa repair and is overexpressed in gastric cancer. We investigated: (a) whether H. pylori, and in particular H. pylori VacA toxin, affected VEGF expression in gastric epithelial cells in culture; and (b) the signal transduction p...
BACKGROUND Helicobacter pylori (H. pylori)-specific genotypes have been closely correlated with an increased risk of gastric cancer (GC). The present study aimed to determine the distribution of H. pylori pathogenic genotypes amongst Iranians infected with strains representing European ancestry in areas with different GC incidence. METHODS A total of 138 H. pylori isolates from ten districts...
Recently, we reported that the patterns of antibodies to Helicobacter pylori protein antigens in serum may be useful for screening patients at high risk for ulcers (P. Aucher et al., J. Clin. Microbiol. 36:931-936, 1998). Here we report the identification, by a combination of electrophoretic, immunochemical, and protein sequencing methods, of five antigens that correspond to this antibody patte...
The VacA toxin secreted by Helicobacter pylori is considered to be an important virulence factor in the pathogenesis of peptic ulcer disease and gastric cancer. VacA monomers self-assemble into water-soluble oligomeric structures and can form anion-selective membrane channels. The goal of this study was to characterize VacA-VacA interactions that may mediate assembly of VacA monomers into highe...
BACKGROUND & AIMS The Helicobacter pylori toxin vacuolating cytotoxin (VacA) promotes gastric colonization, and its presence (VacA(+)) is associated with more-severe disease. The exact mechanisms by which VacA contributes to infection are unclear. We previously found that limited exposure to VacA induces autophagy of gastric cells, which eliminates the toxin; we investigated whether autophagy s...
Naturally occurring noncytotoxic vacA type s2 strains of Helicobacter pylori have a 12-residue extension to the vacuolating cytotoxin (VacA) compared with cytotoxic type s1 strains. We show that adding the region encoding this extension to type s1 vacA completely abolishes vacuolating cytotoxin activity but has no effect on VacA production.
Vacuolating cytotoxin A, VacA, is one of the major virulence factors produced by H. pylori and its gene polymorphism might play a major role in strain virulence of H. pylori itself. VacA is produced as a 140 kDa protoxin which undergoes multiple cleavage reactions to give an 88 kDa mature toxin. The 88 kDa protoxin is further cleaved by unknown proteases into 55 kDa C terminal domain (p55) and ...
Allelic variation among Helicobacter pylori vacA occurs in the signal and middle region of the gene. The aim of the study was to investigate alleleic variation of vacA among H. pylori strains from three regional areas of China and the relationship between vacA alleles and PUD. DNA extracted from 88 clinical isolates of H. pylori was analyzed by type-specific PCR and reverse hybridization line p...
Colonization of the mucosa of the stomach and the duodenum by Helicobacter pylori is the major cause of acute and chronic gastroduodenal pathologies in humans. Duodenal ulcer formation strongly correlates with the expression of an antigen (CagA) that is usually coeexpressed with the vacuolating cytotoxin (VacA), a protein that causes ulceration in the stomach of mice. However, the relationship ...
Background: Helicobacter pylori has been classified as the class I carcinogenic agent by world health organization. Colonization of the human stomach with H. pylori is a risk factor for gastroduodenal diseases. The secreted vacA toxin is an important H. pylori virulence factor that causes multiple alterations in gastric epithelial cells and T cells. Several families of vacA alleles have been de...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید