The type IV secretion system (T4SS) is a major virulence determinant of the gastric pathogen Helicobacter pylori. The CagL protein is a specialized adhesin of the corresponding T4SS pilus, which establishes initial contact with the integrin β1 receptor on host target cells. Recent studies proposed that Y58 and E59 amino acid polymorphisms in CagL increase the virulence of H. pylori strains by e...

BACKGROUND Helicobacter pylori is a vertically inherited gut commensal that is carcinogenic if it possesses the cag pathogenicity island (cag PaI); infection with H.pylori is the major risk factor for gastric cancer, the second leading cause of death from cancer worldwide (WHO). The cag PaI locus encodes the cagA gene, whose protein product is injected into stomach epithelial cells via a Type I...

BACKGROUND The cagA gene is a marker for the presence of the cag pathogenicity island, and the presence of cagA positive strains of Helicobacter pylori can identify individuals with a higher risk of developing gastrointestinal diseases. AIMS To study the interaction between H. pylori cagA(+) and cagA(-) strains and the gastric mucosa. METHODS Patients with H. pylori associated gastritis and...

BACKGROUND There are few literatures evaluating the association between cytotoxin-associated gene A (CagA) positive strains of Helicobacter pylori (HP) and the severity of coronary heart disease (CHD). This study was designed to investigate this association. METHODS Medical and drug history of 112 consecutive patients who were candidate for coronary angiography were taken. Fasting blood sampl...

helicobacter pylori (h. pylori) is classified as a class i carcinogen. the low infection rate seen in developed countries (8.9%) compared with a high infection rate (52%-98%) in developing countries indicates a strong association between infection prevalence and socioeconomic status. adhesion of h. pylori to gastric epithelial cells is an important aggressive factor. one of the genes that encod...

AIMS To investigate: (1) whether Helicobacter pylori directly induces interleukin-8 (IL-8) message expression and protein secretion in established gastric epithelial cell lines; and (2) if CagA/cytotoxin positive and negative strains of H pylori differ in their ability to induce epithelial IL-8. METHODS Gastric epithelial cell lines were co-cultured with H pylori NCTC 11637 and 10 clinical is...

AIM To evaluate serum paraoxonase(PON)-1 activity and carotid intima-media thickness (CIMT) in patients with Cytotoxin-associated antigen(CagA)-positive and negative Helicobacter pylori strains. PATIENTS AND METHODS The study group included a total of 134 individuals, of whom 103 were H. pylori positive, and 31 were H. pylori negative. Five biopsies were collected from each patient for histol...

Helicobacter pylori persists in the human stomach despite eliciting both cellular and humoral immune responses and inducing proinflammatory cytokines. To determine whether local humoral and cytokine responses are related to each other and to histologic responses, we studied 66 Japanese patients who underwent gastroscopy. Using specific enzyme-linked immunosorbent assays, we examined gastric ant...

BACKGROUND Helicobacter pylori is a pathogenic bacterium that causes various gastrointestinal diseases. The most common gastric malignancies associated with H. pylori are gastric cancer and lymphoma of mucosa associated lymphoid tissue (MALT). Helicobacter pylori virulence genes, namely cagA and vacA, are known to be associated with malignancy development. Conventionally, cagA and vacA were cla...

BACKGROUND/AIMS Infection with Helicobacter pylori strains harbouring the cagA gene (cagA+) is associated with an increased risk of developing peptic ulcer and gastric cancer. The aim of this study was to assess whether H pylori isolates with different cagA status were present in patients with non-ulcer dyspepsia, and whether a variable cagA status is relevant to histological gastric mucosal da...