background : helicobacter pylori ( h. pylori ) infection is known as a major etiologic factor for a variety of gastroduodenal diseases. in iran, with a high rate of h. pylori infection close to 90%, numerous studies have revealed many aspects of interaction between the bacterium, mucosal surface and induction of disease outcome. the organism is genetically diverse and several virulence factors ...

Abstract Background The cytotoxin-associated gene A ( cagA ) is one of the most important virulence factors Helicobacter pylori H. ). There a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in C-terminal CagA protein. This thought to play an role pathogenesis gastrointestinal diseases. aim this study was investigate diversity 3? variable and amino acid polymorphisms EPIYA segments ...

The prevalence of clarithromycin resistance-associated mutations, the cytotoxin-associated gene (cagA), and the various vacuolating cytotoxin (vacA) genotypes was determined in 50 gastric biopsy specimens from Helicobacter pylori-infected patients, using line probe assays. The clarithromycin resistance-associated mutation A2143G was detected in H. pylori strains from 26% of the specimens, which...

BACKGROUND VacA and CagA proteins have been reported to be major virulence factors of Helicobacter pylori. However, antibodies against these proteins are frequently found in the sera of Japanese patients regardless of their gastroduodenal status. AIM To evaluate the expression of VacA and CagA proteins by H pylori strains isolated in Japan. METHODS By using specific antibodies raised agains...

Helicobacter pylori, a gram-negative bacterium, possesses two important virulence factors: the vacuolating toxin (vacA), and the cytotoxin-associated gene product (cagA). The aim of the present study was to evaluate the presence of H. pylori in the stomach and oral cavity of humans and compare the cagA and vacA genotypes of H. pylori found in different samples (stomach, saliva and dental plaque...

BACKGROUND AND OBJECTIVES Helicobacter pylori has been strongly associated with peptic ulcer diseases, chronic gastritis, ulcers, and reported as a risk factor for gastric cancer, too. The vaculating cytotoxin (vacA), the cytotoxin associated genes (cagA), the induced by contact with epithelium factor antigen (iceA gene), blood adhesion binding antigen (babA2), and outer membrane protein oipA h...

BACKGROUND The development of clinically significant disease in South Africa is associated with the vacuolating cytotoxin gene (vacA) s1 genotype but not with the presence of the cytotoxin associated gene cagA. cagA occurs in >95% of South African isolates and is a variable marker for the entire cag pathogenicity island (PAI). AIM To characterise the cagPAI in South African isolates and to in...

Chronic infection with the Gram-negative bacterium Helicobacter pylori is a major risk factor for the development of gastric cancer. Accumulating evidence indicates that the H. pylori virulence determinant cytotoxin-associated gene A (CagA) has a key oncogenic role in the process. Certain biological activities of CagA require its tyrosine phosphorylation by host cell kinases. In this issue of t...

conclusions the most predominant vaca genotypes in our areas were s1/m2 and s1/m1, which regard as the genotypes with more virulence intensity. the h. pylori vacas1a, caga genotypes have a significant relationship with the presence of pud and gc in iranian patients with dyspepsia. results in this study, vaca genotypes s1/m2, s1/m1, s2/m2 and s2/m1 were determined in 43.4%, 19.3%, 13.2% and 6% o...