1. Graduate Institute of Physiology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan;
2. Department of Pediatrics, National Taiwan University College of Medicine, Taipei, Taiwan;
3. Graduate Institute of Anatomy and Cell Biology, National Taiwan University College of Medicine, Taipei, Taiwan;
4. Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan; and
5. Department of Pathology, University of Chicago, Chicago, Illinois