1. Tohoku University School of Medicine, Sendai, Japan. E-mails: itoi-eiji@med.tohoku.ac.jp, koyomoe@med.tohoku.ac.jp, jun_gene@yahoo.co.jp
2. Kurihara Central Hospital, Kurihara, Japan. E-mail: nagamoto@med.tohoku.ac.jp
3. Sendai City Hospital, Sendai, Japan. E-mail: sanohirotaka@med.tohoku.ac.jp