1 State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong; CUHK Shenzhen Research Institute, Shenzhen, China. Electronic address: wonghei@cuhk.edu.hk.
2 State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences and Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong; Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Hong Kong; CUHK Shenzhen Research Institute, Shenzhen, China. Electronic address: wukakei@cuhk.edu.hk.