1. Department of Internal Medicine, Center for Liver Diseases, Seizankai Kiyokawa Hospital
2. Department of Virology II, National Institute of Infectious Diseases
3. Department of Internal Medicine, Division of Gastroenterology and Hepatology, St. Marianna University School of Medicine
4. Department of Gastroenterology and Hepatology, Tokyo Medical University Hachioji Medical Center
5. Department of Internal Medicine, Graduate School of Medicine, The University of Tokyo