1. From the Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
2. Center for Regenerative Medicine Research, Faculty of Medicine, SAGA University, Saga, Japan
3. Faculty of Medicine, Department of Thoracic and Cardiovascular Surgery, Saga University, Saga, Japan
4. Department of Surgery, Division of Gastroenterological, General and Transplant Surgery Jichi Medical University, Tochigi, Japan