1. Shinozaki Medical Clinic, Utsunomiya, Japan
2. Division of Gastroenterology, Department of Medicine, Jichi Medical University, Shimotsuke, Japan
3. Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
4. Royal Free Unit for Endoscopy, The Royal Free Hospital, University College London Institute for Liver and Digestive Health, London, United Kingdom of Great Britain and Northern Ireland