1 Department of Gastroenterology and Hepatology, Research Institute Amsterdam Gastroenterology and Metabolism, Amsterdam University Medical Center, Amsterdam, The Netherlands.
2 Wolfson Unit for Endoscopy, St Mark's Hospital, London, UK; Department of Surgery and Cancer, Imperial College London, London, UK.
3 Wolfson Unit for Endoscopy, St Mark's Hospital, London, UK; Department of Surgery and Cancer, Imperial College London, London, UK; Department of Metabolism, Digestion, and Reproduction, Imperial College London, London, UK.