1. Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University/Sinai Hospital Program in Internal Medicine, Baltimore, Maryland.
2. Division of Gastroenterology and Hepatology, University of Arkansas for Medical Sciences, Little Rock, Arkansas.
3. Division of Gastroenterology, Department of Medicine, Walter Reed National Military Medical Center, Bethesda, Maryland.
4. Division of Veterinary Medicine, Department of Veterinary Surgery, Uniformed Services University, Bethesda, Maryland.
5. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
6. Division of Gastroenterology, Sinai Hospital of Baltimore, Baltimore, Maryland.