1. Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine,1-1-20 Daiko Minami, Higashi-ku, Nagoya, Aichi 461-8673, Japan
2. Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine,3-1-1 Asahi, Matsumoto, Nagano 390-8621, Japan
3. Laboratory of Bacteriology, Aichi Prefectural Institute of Public Health,7-6 Nagare, Tsuji-machi, Kita-ku, Nagoya, Aichi 462-8576, Japan
4. Department of Bacteriology, Nagoya University Graduate School of Medicine,65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan