1 Academic Department of Gastroenterology, Medical School of National and Kapodistrian University of Athens, General Hospital of Athens "Laiko", Zografou, Greece.
2 Department of Pathology, Aretaieion Hospital, Medical School, National and Kapodistrian University of Athens, Zografou, Greece.
3 Translational Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.