کچ ي هد دنب هعطق شور كي هلاقم نيا رد ي واصت ي گنر ر ي هقبط زا هدافتسا اب ريگداي ياتاموتا رب ينتبم يزاف هدننک يدنب م داهنشيپ يلولس ي ددرگ . نيا رد هقبط نيناوق و تيوضع عباوت يلولس ريگداي ياهاتاموتا زا يا هعومجم كمك هب هدننک يدنب يم ديلوت کيتاموتا روط هب يزاف دنوش . ا يلولس ريگداي ياتاموتا ز نِگمه ان مِاگمهان هب زاب نيرتهب نتفاي يارب يرازبا ناونع تسا هدش هدافتسا يزاف تيوضع عباوت راتخاس . رد اتاموت...

  Background and Objective: Helicobacter pylori has several strains with different degrees of virulence. The aim of this study was to detect two major important virulence factors, cagA/vacA genotypes, and to determine correlations among different cagA/vacA genotypes and histological features of chronic gastritis in Iranian patients. Methods: In this cross- sectional study, Gastric bi...

AIMS Helicobacter pylori infection is the major cause of peptic ulceration and gastric cancer, and an important virulence determinant is its vacuolating cytotoxin vacA. Previously, we have described allelic variation in vacA which determines toxin activity and disease risk. Here we aimed to quantify vacA mRNA expression in the human stomach, define its genetic determinants and assess how well i...

Chronic gastritis induced by Helicobacter pylori is a strong risk factor for the development of distal gastric adenocarcinoma. A specific host response to H. pylori that may contribute to gastric carcinogenesis is epithelial cell apoptosis. The aim of this study was to investigate the capacity of H. pylori vacuolating toxin (VacA) to induce gastric epithelial cell apoptosis. When cocultured wit...

Platelets were activated under the infection with H. pylori in human and mice. We investigated the role of VacA, an exotoxin released by H. pylori in this context. Acid-activated VacA, but not heated VacA, induced platelet CD62P expression. However, VacA reacted with none of the alleged VacA receptors present on platelet membranes. We therefore analyzed VacA associated proteins obtained through...

Helicobacter pylori VacA is a channel-forming toxin unrelated to other known bacterial toxins. Most H. pylori strains contain a vacA gene, but there is marked variation among strains in VacA toxin activity. This variation is attributable to strain-specific variations in VacA amino acid sequences, as well as variations in the levels of VacA transcription and secretion. In this review, we discuss...

The Helicobacter pylori VacA toxin is an 88-kDa secreted protein that causes multiple alterations in mammalian cells and is considered an important virulence factor in the pathogenesis of peptic ulcer disease and gastric cancer. We have shown previously that a VacA mutant protein lacking amino acids 6 to 27 (Delta6-27p88 VacA) is able to inhibit many activities of wild-type VacA in a dominant-n...

The Helicobacter pylori vacuolating toxin VacA causes several effects on mammalian cells in vitro, including intracellular vacuolation, formation of pores in the plasma membrane and apoptosis. When added to cells, VacA becomes associated with detergent-resistant membranes, indicating that it binds preferentially to lipid rafts. In the present study, we have used atomic force microscopy to exami...

AIM The cagA and vacA profiles and their association with clinical findings show a distinct geographical distribution. In the present study, we aimed to determine the cagA status and vacA allelic subtypes in strains isolated from a university hospital in Ankara and to evaluate their associations with histopathological and endoscopic findings. MATERIALS AND METHODS A total of 120 H. pylori str...

Vacuolating cytotoxin A (VacA) is a secreted pore-forming toxin and one of the major virulence factors of Helicobacter pylori (H. pylori), which actively supports the persistence and survival of the bacteria in the special ecological niche of the human stomach. H. pylori genomes harbor different allelic forms of the vacA gene, which translate into functionally distinct VacA toxin types. VacA in...