Learn More
Infection with Helicobacter pylori strains containing the cag Pathogenicity Island (cag PAI) is strongly correlated with the development of severe gastric disease, including gastric and duodenal ulceration, mucosa-associated lymphoid tissue lymphoma, and gastric carcinoma. Although in vitro studies have demonstrated that the expression of genes within the(More)
Prostaglandins (PGs) are potent lipid mediators that are produced during infections and whose synthesis and signaling networks present potential pharmacologic targets for immunomodulation. PGE(2) acts through the ligation of four distinct G protein-coupled receptors, E-prostanoid (EP) 1-4. Previous in vitro and in vivo studies demonstrated that the(More)
Chronic inflammation in the stomach induces metaplasia, the pre-cancerous lesion that precedes inflammation-driven neoplastic transformation. While Hedgehog signaling contributes to the initiation of some cancers, its role in gastric transformation remains poorly defined. We found that Helicobacter-infected C57BL/6 mice develop extensive mucous cell(More)
'Flexispira rappini' is a provisional name given to gram-negative, microaerophilic, motile, spindle-shaped micro-organisms with spiral periplasmic fibres and bipolar tufts of sheathed flagella. Several investigators, including Kirkbride, Romero, and Archer isolated strains possessing this morphology. Previously, the phylogenetic position of three(More)
Enterohemorrhagic Escherichia coli (EHEC), particularly serotype O157:H7, causes hemorrhagic colitis, hemolytic uremic syndrome, and even death. In vitro studies showed that Shiga toxin 2 (Stx2), the primary virulence factor expressed by EDL933 (an O157:H7 strain), is encoded by the 933W prophage. And the bacterial subpopulation in which the 933W prophage(More)
Gastritis due to Helicobacter pylori is induced by a Th1-mediated response that is CD4 cell and gamma interferon (IFN-gamma) dependent. T-bet is a transcription factor that directs differentiation of and IFN-gamma secretion by CD4+ Th1 T cells. The goal of this study was to use two mouse models to elucidate the role of T-bet in gastritis due to H. pylori.(More)
Thirty-seven gnotobiotic piglets from seven litters were infected with either Helicobacter pylori N6 or urease-negative H. pylori N6ureG::Km which contains an insertion in the ureG gene and produces inactive urease. To produce achlorhydria, piglets were treated throughout the experiment with omeprazole (5 mg intravenously every 12 h) and ranitidine (75 mg(More)
The current study tests the hypothesis that chronic atrophic gastritis from hypochlorhydria in the gastrin-deficient mouse predisposes the stomach to gastric cancer. Gross morphology and histology of 12-month-old wild-type (WT), gastrin-deficient (G-/-) and somatostatin-deficient (SOM-/-) mice were examined. Parietal and G cells, Ki67, TUNEL, villin and(More)
Helicobacterpylori possesses two flagellin molecules, MA, the major species, and FlaB, which is expressed in minor amounts. This study sought to determine if one or both flagellin species are necessary for colonization or persistence by H. pylon. Thirty-six gnotobiotic piglets from six litters were given one of four isogenic strains of H. pylon orally. The(More)