1. Department of Gastroenterology, Shrewsbury & Telford Hospitals NHS Trust, Princess Royal Hospital, Apley Castle, Telford, Shropshire, UK
2. Neurogastroenterology Group, Blizard Institute of Cell & Molecular Science, Wingate Institute of Neurogastroenterology, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK