The vacuolating toxin A (VacA) is one of the most important virulence factors in Helicobacter pylori-induced damage to human gastric epithelium. Using human gastric epithelial cells in culture and broth culture filtrate from a VacA-producing H. pylori strain, we studied 1) the delivery of VacA to cells, 2) the localization and fate of internalized toxin, and 3) the persistence of toxin inside t...

Human infection by the bacterium Helicobacter pylori (Hp) may lead to severe gastric diseases by an ill-understood process involving several virulence factors. Among these, the cytotoxin VacA is associated with higher tissue damage. In this study, the isolated frog stomach model was used to characterize the acute effects of VacA on the gastric epithelium. Our results show that VacA partially in...

صلاخلا ــ ة : مت ةقرولا هذه يف ءاشنإ يف هدعاسملل مدقتم ماظن بناوج ذيفنتو ميمصت ضرع قتو و مي ءادأ حيحصت تارفش لأا ءاطخ ةليلق لا ةناتم ، ةينبم ىلع ءوفاكتلا رايتخا . موقي امه نيتيسيئر نيتفيظوب ةساردلا هذه يف مدقتملا ماظنلا : 1 ادأ باسحل ةيزاوتملا هاآاحملا ء تارفش حيحصت لأا ءاطخ ةليلق نمزب ةفاثكلا ادج ريصق ةنراقم ةمظنأب ةاآاحملا ةدوجوملا . 2 ةليلق ءاطخلأا حيحصت تارفشو فعضلا قطانم صحف نع ة...

La eficiencia reproductiva de los hatos bovinos carne es el factor preponderante, que determina la productividad las empresas ganaderas, a su vez, depende utilización métodos disponibles en biotecnología reproducción; cuales incluyen congelación semen, inseminación artificial, sincronización y/o inducción ovulación y estro, superovulación, transferencia embriones, bisección inyección intra-cito...

We describe two subclones of Helicobacter pylori, isolated contemporaneously from a human stomach, which differ markedly in the vacuolating cytotoxin gene, vacA, but whose near identity in sequences outside this locus implies a very recent common origin. The differences are consistent with homologous recombination with DNA from another strain and result in a changed vacA midregion and, importan...

We evaluated a new immunoblot assay (Helicoblot 2.1) for Helicobacter pylori infection and CagA and VacA status by using serum samples from 222 patients. The test accurately detected H. pylori infection and VacA status, but improvements in the interpretation criteria are required before it can be recommended for determination of CagA status.

Helicobacter pylori, a common pathogen that causes chronic gastritis and cancer, has evolved to establish persistent infections in the human stomach. Epidemiological evidence suggests that H. pylori with both highly active vacuolating cytotoxin A (VacA) and cytotoxin-associated gene A (CagA), the major virulence factors, has an advantage in adapting to the host environment. However, the mechani...

Helicobacter pylori has been strongly associated with gastritis, gastric and duodenal ulcers, and it is a risk factor for gastric cancer. Two major virulence factors of H. pylori have been described: the cytotoxin-associated gene product (cagA) and the vacuolating toxin (vacA). Since considerable geographic diversity in the prevalence of H. pylori virulence factors has been reported, the aim of...