1. General Hospital “Novi Pazar” , Novi Pazar , Serbia , Department of Gastroenterohepatology
2. University of Kragujevac, Faculty of Medical Sciences , Department of Internal medicine , Serbia
3. University of Kragujevac, Faculty of Medical Sciences , Center for Molecular Medicine and Stem Cell Research , Serbia
4. University of Kragujevac, Faculty of Medical Sciences , Department of Surgery , Serbia
5. Health Center Tutin , Serbia
6. University of Kragujevac, Faculty of Medical Sciences , Department of Pathophysiology , Serbia
7. University of Kragujevac, Faculty of Medical Sciences , Department of Pathology , Serbia