1. Department of Urology, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
2. Department of Chemistry, Graduate School of Science, Kyushu University, Fukuoka 819-0395, Japan
3. Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan
4. Keio University WPI Bio2Q Research Center and Central Institute for Experimental Animal, Kanagawa 210-0821, Japan