1. Department of Health and Environmental Sciences, Kyoto University Graduate School of Medicine, Yoshida, Kyoto 606-8501, Japan
2. Daiichi University of Pharmacy, Fukuoka 8150037, Japan
3. Department of Sanitary Technology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu 610061, China
4. Department of Preventive Medicine, St. Marianna University School of Medicine, Kawasaki 2168511, Japan