Affiliation: | 1. Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea;2. Digestive disease center, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea;3. Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Korea;4. Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea |