Hepatitis C

Epidemiology, treatment, and outcomes research in chronic hepatitis C. Division investigators are studying the prevalence and treatment of hepatitis C in special populations, such as patients with HIV, those with comorbid psychiatric disease, substance abusers, and veterans. We are also evaluating health-related quality of life and fatigue in patients with hepatitis C virus infection and the impact of treatment on outcomes.

Colorectal Cancer

Screening for colorectal cancer. Members of the division are evaluating colorectal cancer screening in special populations (women, veterans, immigrants, minorities, and patients with HIV) and investigating the use of CT colonography (virtual colonoscopy) for the detection of colorectal polyps and cancers.

Immune Systems with Pathogenic Organisms

Interaction of the mucosal and hepatic immune systems with pathogenic organisms. Division investigators are studying the effect of HIV-1 infection on innate immune cells in the gastrointestinal tract and periphery. Under particular examination is the interaction between HIV-1 and mucosal and hepatic populations of NKT cells and cdT cells. Additional studies have focused on natural and synthetic ligands for the innate immune system, such as NKT cells and toll-like receptors (TLRs). We are also studying the effect of HIV-1 on conventional T-cell populations in the gastrointestinal tract throughout the course of HIV-1 disease, but most interestingly during the primary infection period.

Acid-Mediated Esophageal Diseases

Evaluation of host and bacterial factors involved in the development of acid-mediated esophageal diseases. Members of the division have demonstrated the negative association between H. pylori colonization and the presence of esophageal disease among veterans. We have also demonstrated the presence of bacteria in the esophagus other than oropharyngeal flora and are looking to discern differences in esophageal bacterial colonization based on different acid-mediated disease states. Division investigators continue to explore the interplay between polymorphisms in IL1-beta and bacterial colonization in the development of GI pathology.

Other Active Research Areas

Animal models for gastroesophageal reflux disease.

The protective role of H. pylori infection in the development of Barrett's esophagus and esophageal adeno-carcinoma.

Outcomes and indications of bariatric surgery for obesity.

The application of simulators and animal models to endoscopic training.

Conscious sedation for endoscopy.

Alternate pathways of metabolism of normal intermediates in cholesterol synthesis and their biologic role as oxysteroid ligands for nuclear receptors.