1. Gastroenterology Unit, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy;
2. Centre for Oesophageal Diseases, Guy's and St. Thomas Hospital, Westminster Bridge Road, London, UK;
3. Division of Gastroenterology, Department of Surgery, Oncology and Gastroenterology, University of Padua, Padua, Italy;
4. Institute of Information Science and Technologies “A. Faedo,” National Research Council of Italy (CNR), Pisa, Italy;
5. Department of Dietetics, Guy's and St Thomas' NHS Foundation Trust, London, UK;
6. Peter Gorer Department of Immunobiology, School of Immunology and Microbial Sciences, School of Medicine, Guys Hospital, Kings College London, London, UK.