[1] Keio Univ, Sch Med, Dept Physiol, Tokyo 160, Japan
[2] Keio Univ, Sch Med, Dept Orthopaed Surg, Tokyo, Japan
[3] Ichikawa Gen Hosp, Tokyo Dent Coll, Dept Orthopaed Surg, Chiba, Japan
[4] Tokyo Med & Dent Univ, Grad Sch Med, Dept Neurol & Neurol Sci, Tokyo, Japan
[5] Namegata Dist Gen Hosp, Dept Clin Lab, Ibaraki, Japan
[6] Osaka Natl Hosp, Natl Hosp Org, Inst Clin Res, Div Regenerat Med, Osaka, Japan
[7] Osaka Natl Hosp, Natl Hosp Org, Dept Neurosurg, Osaka, Japan
[8] RIKEN, BioResource Ctr, Subteam Manipulat Cell Fate, Ibaraki, Japan
[9] Keio Univ, Sch Med, Bridgestone Lab Dev & Regenerat Neurobiol, Tokyo, Japan
[10] Nagoya City Univ, Grad Sch Med Sci, Dept Dev & Regenerat Biol, Aichi, Japan