1. From the Division of Biofunctional Science, Tohoku University Biomedical Engineering Research Organization, Sendai, Japan; the
2. From the Division of Biofunctional Science, Tohoku University Biomedical Engineering Research Organization, Sendai, Japan; the2Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan; and the
3. Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan; and the
4. Department of Neurology, University of Go¨ttingen, Germany.