1. Department of Biochemistry, Kawasaki Medical School, Okayama, Japan
2. Laboratory of Microbiology, Showa Pharmaceutical University, Machida, Japan
3. Department of Cerebrovascular Disease and Neurology, Hakujyuji Hospital, Fukuoka, Japan
4. Department of Otorhinolaryngology, Faculty of medicine, Fukuoka University, Fukuoka, Japan