1. Department of Stem Cell Biology and Histology, Tohoku University Graduate School of Medicine, Sendai, Japan.
2. Department of Anatomy and Anthropology, Tohoku University Graduate School of Medicine, Sendai, Japan.
3. Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan.
4. Medical College of Georgia, Georgia Regents University, Augusta, Georgia.
5. Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California.