1. From the Department of Anatomy, Hiroshima University School of Dentistry, Hiroshima 734-8553, Japan
2. From the Department of Orthodontics, Hiroshima University School of Dentistry, Hiroshima 734-8553, Japan
3. Department of Pharmacology, School of Dentistry, Showa University, Tokyo 142-8555, Japan
4. Department of Molecular Genetics, Faculty of Medicine, Kyoto University, Kyoto 606-8507, Japan
5. Research Center Kyoto, Bayer Yakuhin, Ltd., Kyoto 619-0216, Japan