1. First Department of Surgery, National and Kapodistrian University of Athens, Laikon General Hospital, Athens, Greece;
2. Third Department of Surgery, National and Kapodistrian University of Athens, Attikon University Hospital, Chaidari, Greece;
3. Laboratory of Experimental Surgery and Surgical Research N.S. Christeas, Athens Medical School, Athens, Greece;
4. Second Department of Surgery, Aristotle University of Thessaloniki, G.Gennimatas General Hospital, Thessaloniki, Greece;
5. Fourth Department of Surgery, National and Kapodistrian University of Athens, Attikon University Hospital, Chaidari, Greece