Arginine was the only amino acid used by Clostridium difficile that permitted cytotoxin synthesis in a peptone-based medium. Synthesis of cytotoxin was delayed when glucose was used as the substrate. Addition of rifampin or puromycin to cultures prior to release of cytotoxin inhibited the release of cytotoxin, suggesting that a protein essential for cytotoxin release is synthesized after cytoto...

PURPOSE Helicobacter pylori infection by virulent strains is associated with gastric adenocarcinoma. We aimed to determine whether infection with virulent H. pylori preceded precancerous gastric hypochlorhydria and atrophy in gastric cancer relatives and quantify the extent of virulence factor evolution. EXPERIMENTAL DESIGN H. pylori strains from 51 Scottish gastric cancer relatives were char...

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 strains have two classical virulence genes, the cytotoxinassociated a ( caga ) gene and the vacuolating cytotoxin a ( vaca ) gene, which are located in the cag pathogenicity island ( cag pai). serum immunoglobulin g (igg) antibodies to h. pylori , especially, the caga antigen may be a reliable marker for selection of dyspeptic patients for upper endoscopy. method...

Panton-Valentine Leukocidin (PVL) is a cytotoxin produced by Staphylococcus aureus that causes leukocyte destruction and tissue necrosis. Therefore, this study aimed to detect the rate, antimicrobial susceptibility, associated risk factors, phylogenetic relationship of PVL-positive S. nasal carriers among patients nurses. The research methods included collection 315 specimens obtained from inpa...

Apoptosis is not only essential for homeostasis in normal cells but also in cancer cells, in which it is associated with cell death mechanisms caused by novel therapeutics. We have previously reported that interleukin-13 receptors (IL-13R) are constitutively overexpressed on a majority of human malignant glioma cell lines and primary cell cultures. In addition, we have reported that IL-13 cytot...

When axenic mice fed a commercial diet were monoassociated with two toxigenic strains of Clostridium difficile, 100% of them died 3 days after inoculation and both enterotoxin and cytotoxin were produced in their intestinal tract. However, when axenic mice were fed various semisynthetic diets before C. difficile challenge, some of them survived and their fecal cytotoxin and enterotoxin producti...

Bacillus cytotoxicus belongs to the cereus group that also comprises foodborne pathogen sensu stricto, anthracis causing anthrax, as well biopesticide thuringiensis. The first B. was isolated in context of a severe food poisoning outbreak leading fatal cases diarrheal disease. Subsequent characterization strain led conclusion this highly cytotoxic and eventually resulted description novel speci...

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...