1. Division of Microbiology, Department of Pathology and Microbiology Nihon University School of Medicine, Tokyo, Japan
2. Department of Pediatrics and Child Health Nihon University School of Medicine, Tokyo, Japan
3. Department of Obstetrics and Gynecology Keck School of Medicine, University of Southern California, Los Angeles, California, USA
4. Department of Physiology Nihon University School of Medicine, Tokyo, Japan