1. Department of Gastroenterology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow India
2. Department of Microbiology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow India
3. Department of Gastroenterology Sheikh Russel National Gastroliver Institute and Hospital Dhaka Bangladesh
4. Department of Gastroenterology Mugda Medical College Dhaka Bangladesh
5. Department of Medicine Dhaka Medical College and Hospital Dhaka Bangladesh