1. Research Institute for Elderly Health, Waseda University, 2-579-15 Mikashima, Tokorozawa, Saitama 359-1192, Japan
2. Department of Biology, Waseda University, 2-2 Wakamatsucho, Shinjuku, Tokyo 162-8480, Japan
3. Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Sanmin, Kaohsiung 80708, Taiwan