1. Institute of Gerontology, The University of Tokyo, Tokyo 113-8656, Japan
2. R&D Department, Sunstar Inc., Tokyo 105-0014, Japan
3. Tokyo Metropolitan Institute for Geriatrics and Gerontology, Tokyo 173-0015, Japan
4. Gerodontology, Department of Oral Health Science, Faculty of Dental Medicine, Hokkaido University, Sapporo 060-8586, Japan
5. Institute for Future Initiatives, The University of Tokyo, Tokyo 113-0033, Japan