1. Department of Medicine; National University Hospital; Singapore
2. Department of Medicine and Therapeutics; The Chinese University of Hong Kong; Hong Kong China
3. Helen and Arthur E. Johnson Beth-El College of Nursing and Health Sciences; University of Colorado; Colorado Springs Colorado USA
4. Department of Pulmonology; University Medical Center Groningen; Groningen The Netherlands
5. Department of Medicine, Research Centre of Heart, Brain, Hormone and Healthy Aging; The University of Hong Kong; Hong Kong
6. Department of Pharmacology and Pharmacy, Research Centre of Heart, Brain, Hormone and Healthy Aging; The University of Hong Kong; Hong Kong