1Departments of Biochemistry and Oral Anatomy, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142
2Department of Dental Research, National Institute of Health, 2-10-35 Kamiosaki, Shinagawa-ku, Tokyo 141, Japan
3Saint Vincent's Institute of Medical Research, 41 Victoria Parade, Melbourne 3065, Australia