1. Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
2. Department of Biochemistry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
3. Department of Neurosurgery, Graduate school of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan