1. Department of Comparative Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
2. Ralph H. Johnson VA Medical Center Department of Research Service, Charleston, South Carolina, USA
3. Department of Medicine, Nutrition Section, Division of Gastroenterology, Medical University of South Carolina, Charleston, South Carolina, USA
4. Department of Medicine, Infectious Disease Division, Medical University of South Carolina, Charleston, South Carolina, USA
5. Department of Psychiatry, Nutrition Section, Division of Gastroenterology, Medical University of South Carolina, Charleston, South Carolina, USA