1. Endocrine Unit, 2nd Propaedeutic Department of Internal Medicine, School of Medicine, Research Institute and Diabetes Center, Attikon University Hospital, National and Kapodistrian University of Athens, 12641 Athens, Greece
2. 3rd Department of Internal Medicine, School of Medicine, Sotiria General Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece
3. 3rd Department of Surgery, School of Medicine, Attikon University Hospital, National and Kapodistrian University of Athens, 12641 Athens, Greece