1. Department of Gastroenterology and Neurology, Faculty of Medicine, Kagawa University, Takamatsu 761-0793, Japan
2. Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan
3. Department of Gastroenterology, Saitama Medical University International Medical Center, Saitama 350-1298, Japan
4. Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
5. Department of Gastroenterology, Tane General Hospital, Osaka 550-0025, Japan
6. Department of Gastroenterology, Kochi Red Cross Hospital, Kochi 780-0026, Japan
7. Department of Gastroenterological Surgery, Faculty of Medicine, Kagawa University, Takamatsu 761-0793, Japan
8. Division of Gastroenterology and Nephrology, Faculty of Medicine, Tottori University, Tottori 683-8504, Japan