1. Division of Pharmacotherapeutics, Faculty of Pharmacy, Keio University, Minato-ku, Tokyo 105-8512, Japan
2. Graduate School of Media and Governance, Keio University, Fujisawa, Kanagawa 252-0882, Japan
3. Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University, Shinjuku-ku, Tokyo 160-8582, Japan
4. Division of Gastroenterology, Department of Internal Medicine, The University of Michigan Medical School, Ann Arbor, MI, 48109, USA