1. Department of Metabolism and Endocrinology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka 810-8563, Japan
2. Department of Cardiology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka 810-8563, Japan
3. Department of Internal Medicine, Itoshima Medical Association Hospital, Fukuoka 819-1112, Japan
4. Department of Pathology and Cell Biology, Faculty of Medicine, University of the Ryukyus, Okinawa 903-0215, Japan