1. Department of Surgery, Aleppo University Hospital, Aleppo, Syria
2. Medicine, Weill Cornell Medical College, Qatar
3. Faculty of Medicine, Syrian Private University, Damascus, Syria
4. Faculty of Medicine, Aleppo University, Aleppo, Syria
5. Faculty of Medicine of Algiers, University Algiers
6. Internal Medicine Department, Hamad Medical Corporation, Doha, Qatar
7. Department of surgery, Aleppo University Hospital, Aleppo, Syria.