1. Graduate School of Pharmaceutical SciencesTohoku University, 6-3, Aza-Aoba Aoba-ku Sendai 980-8578 Japan
2. Reseach Institute for Biological FunctionsChubu University 1200 Matsumoto-cho Kasugai Aichi 487-8501 Japan
3. Division of Infectious DiseasesInternational Research Institute of Disaster ScienceTohoku University and Tohoku Medical Megabank Organization Sendai 980-8575 Japan