1. Gastroenterology, Robert Wood Johnson University, New Brunswick, New Jersey, United States
2. Gastroenterology, Methodist Hospital, Dallas, Texas, United States
3. Borland-Groover Clinic, Jacksonville, Florida, United States
4. Gastroenterology, Mount Sinai Hospital, New York, New York, United States
5. Gastroenterology, Mytilene Hospital, Mytilene, Greece
6. Gastroenterology, Latpikin, Athens, Greece
7. Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan
8. Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
9. Gastroenterology, University of Sao Paulo Medical School, Sao Paulo, Brazil