1. Kyushu University, Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Fukuoka, Fukuoka, Japan
2. Nihon University, Division of Gastroenterology and Hepatology, Department of Medicine, Chiyoda-ku, Tokyo, Japan
3. Kyushu University, 3. Department of Gastroenterology and Metabolism, Graduate School of Medical Sciences, Fukuoka, Fukuoka, Japan