1. Department of Surgery, Osaka Metropolitan University School of Medicine, Osaka, Japan
2. Department of Pathology, National Center for Child Health and Development, Setagaya-ku, Tokyo, Japan
3. Department of Pediatric Surgery, National Center for Child Health and Development, Setagaya-ku, Tokyo, Japan
4. Department of Pediatric Surgery, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan