1. Fujisaki Cell Center, Hayashibara Biochemical Labs. Inc., 675-1 Fujisaki, Okayama 702-8006, Japan
2. DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig D-38124, Germany
3. Department of Internal Medicine, National Minami Okayama Hospital, Okayama 701-0304, Japan