1. Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
2. Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
3. Department of Basic and Clinical Sciences, Nicosia University Medical School, Nicosia 2408, Cyprus
4. Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany