1. Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
2. Division of Molecular Microbiology, Iwate Medical University, Yahaba, Iwate, Japan
3. Division of Periodontology, Iwate Medical University School of Dentistry, Morioka, Iwate, Japan
4. Department of Oral Hygiene, Kansai Women's College, Kashiwara, Osaka, Japan