1 Gastroenterology Department, Faculty of Medicine, Hospital de São João, Porto, Portugal; Department of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, Portugal.
2 Gastroenterology Department, Faculty of Medicine, Hospital de São João, Porto, Portugal; Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Portugal; Institute for Molecular and Cell Biology, Porto, Portugal. Electronic address: fm@med.up.pt.
3 Gastroenterology Department, Faculty of Medicine, Hospital de São João, Porto, Portugal.