1. Department of Neural Regenerative Medicine, Research Institute for Frontier Medicine, and Sapporo Medical University School of Medicine, Sapporo, Japan.
2. Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
3. Department of Neurology, and Yale University School of Medicine, New Haven, Connecticut, USA.
4. Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA.
5. Center for Neuroscience and Regeneration Research, VA Connecticut Healthcare System, West Haven, Connecticut, USA.