1. University of Kragujevac, Faculty of Medical Sciences , Department of Dentistry , Kragujevac , Serbia
2. University of Kragujevac, Faculty of Medical Sciences , Department of Microbiology and Immunology, Center for Molecular Medicine and Stem Cell Research , Kragujevac , Serbia
3. University of Defence, Faculty of Medicine , Military Medical Academy , Belgrade , Serbia
4. University of Kragujevac, Faculty of Medical Sciences , Department of Internal Medicine , Kragujevac , Serbia