University of Genova
Italy
Federal University of Minas Gerais
Brazil
University of Minnesota
United States
Cavan General Hospital
Ireland
General Hospital of Piraeus “Tzaneio”
Greece
Fayoum University
Egypt
Shanghai Ninth People's Hospital Director of Gastroenterology
China
Federal University of Minas Gerais
Brazil
University of Belgrade
Serbia
Shandong university of medicine
China
University of Gharyan
Lebanon
Mamata Medical College/
Mamata General and Super-speciality Hospitals,
India