1. Department of Anesthesiology; Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
2. Siriraj GI Endoscopy Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
3. Section of Gastroenterology, Loma Linda University Medical Center, Loma Linda, CA 92354, United States of America
4. Siriraj GI Endoscopy Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand Thailand
5. Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
6. Siriraj GI Endoscopy Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand. Thailand