Colonization of gerbils with Helicobacter pylori O-chain-deficient mutant SS1 HP0826::Kan results in gastritis and is associated with de novo synthesis of extended homopolymers.

The O-chain polysaccharide of Helicobacter pylori is important for colonization and generation of chronic gastritis in mice. There are marked host differences in the development of H. pylori-induced gastric pathology in mice and gerbils.

Effects of EGFR Inhibitor on Helicobacter pylori Induced Gastric Epithelial Pathology in Vivo.

Helicobacter pylori transactivates the Epidermal Growth Factor Receptor (EGFR) and predisposes to gastric cancer development in humans and animal models. To examine the importance of EGFR signalling to gastric pathology, this study investigated whether treatment of Mongolian gerbils with a selective EGFR tyrosine kinase inhibitor, EKB-569, altered gastric pathology in chronic H. pylori infection.

The role of antigenic drive and tumor-infiltrating accessory cells in the pathogenesis of helicobacter-induced mucosa-associated lymphoid tissue lymphoma.

Gastric B-cell lymphoma of mucosa-associated lymphoid tissue type is closely linked to chronic Helicobacter pylori infection. Most clinical and histopathological features of the tumor can be reproduced by prolonged Helicobacter infection of BALB/c mice. In this study, we have addressed the role of antigenic stimulation in the pathogenesis of the lymphoma by experimental infection with Helicobacter felis, followed by antibiotic eradication therapy and subsequent re-infection.

The modern abdominoperineal excision: the next challenge after total mesorectal excision.

Objectives: Examine the cause of local recurrence (LR) and patient survival (S) following abdominoperineal resection (APR) and anterior resection (AR) for rectal carcinoma and the effect of introduction of total mesorectal excision (TME) on APR.

Methods: A total of 608 patients underwent surgery for rectal cancer in Leeds from 1986 to 1997. CRM status and follow-up data of local recurrence and patient survival were available for 561 patients, of whom 190 underwent APR (32.

Immunisation against Helicobacter felis infection protects against the development of gastric MALT Lymphoma.

Unlabelled: The formation of mucosa-associated lymphoid tissue (MALT) in response to Helicobacter pylori infection is closely associated with the development of primary gastric MALT lymphoma.

Aim: To examine whether immunisation against Helicobacter felis can protect against development of MALT lymphoma.

Results: The majority of control infected mice demonstrated MALT formation (13/15) and five developed lymphoma.

Gastric mucosal cytokine and epithelial cell responses to Helicobacter pylori infection in Mongolian gerbils.

Experimental infection with Helicobacter pylori in Mongolian gerbils results in chronic gastritis and gastric cancer. To investigate epithelial cell proliferation, apoptosis, and mucosal cytokine responses in gastritis, Mongolian gerbils were infected with the H pylori SS1 strain. At 4 weeks post-infection, gastritis was predominantly within the antrum, but extended to the corpus in approximately 50% of gerbils by 36 weeks.

Gastric marginal zone lymphoma is associated with polymorphisms in genes involved in inflammatory response and antioxidative capacity.

Gastric marginal zone lymphoma (GMZL) is strongly associated with Helicobacter pylori infection, which induces a chronic inflammatory response. Inflammation can result in DNA damage related to its severity, the cellular antioxidant capacity, and the integrity of DNA repair mechanisms. Interleukin-1 (IL-1) polymorphisms have been shown to be important mediators of inflammation, while glutathione S-transferase GST T1 and GST M1 polymorphisms are believed to affect cellular antioxidant capacity.

Catalase (KatA) and KatA-associated protein (KapA) are essential to persistent colonization in the Helicobacter pylori SS1 mouse model.

Helicobacter pylori infects the human gastric mucosa and elicits an aggressive inflammatory response. Despite the severity of the inflammatory response, the bacterium is able to persist and cause a chronic infection. It is believed that antioxidant defence mechanisms enable this organism to persist.

Distinct gene expression profiles characterize the histopathological stages of disease in Helicobacter-induced mucosa-associated lymphoid tissue lymphoma.

Long-term colonization of humans with Helicobacter pylori can cause the development of gastric B cell mucosa-associated lymphoid tissue lymphoma, yet little is known about the sequence of molecular steps that accompany disease progression. We used microarray analysis and laser microdissection to identify gene expression profiles characteristic and predictive of the various histopathological stages in a mouse model of the disease. The initial step in lymphoma development is marked by infiltration of reactive lymphocytes into the stomach and the launching of a mucosal immune response.

Altered intestinal morphology and immunity in patients with acute necrotizing pancreatitis.

Purpose/background: Impairment of gut barrier function has been demonstrated in patients with severe acute pancreatitis and may contribute to the development of local and systemic septic complications. The underlying mechanisms, however, remain unclear. Against this background, our aims were to investigate the small intestinal epithelial morphology and mucosal immunity in patients with severe acute pancreatitis.

Gastric Helicobacter species infection in murine and gerbil models: comparative analysis of effects of H. pylori and H. felis on gastric epithelial cell proliferation.

C57BL/6 mice and Mongolian gerbils were infected with Helicobacter felis and Helicobacter pylori SS1 strain to investigate the effects of different Helicobacter species on gastric inflammation and epithelial cell proliferation in different animal models. At 4 weeks, gerbils infected with H. pylori or H.

Rates of circumferential resection margin involvement vary between surgeons and predict outcomes in rectal cancer surgery.

Objective: To analyze the potential variability in rates of circumferential resection margin (CRM) involvement between different surgeons and time periods and to determine the suitability of using CRM status as an immediate predictor of outcome after rectal cancer surgery.

Summary Background Data: After disease stage has been taken into account, survival in rectal cancer has been shown to be very variable between surgeons and institutions. One of the major factors influencing survival is local recurrence, and this in turn is strongly related to inadequate tumor excision, particularly at the CRM.

ADAMs (a disintegrin and metalloproteinase) messenger RNA expression in Helicobacter pylori-infected, normal, and neoplastic gastric mucosa.

Helicobacter pylori is a risk factor for gastric cancer, and bacterial-epithelial interactions may be critical in this association. Studies using complementary DNA arrays indicated that the ADAM (A disintegrin and metalloproteinase) genes in gastric epithelial cells are differentially expressed after bacterial-epithelial interactions. Reverse-transcription polymerase chain reaction analysis of gastric biopsy specimens from patients with and without H.