1. First Department of Propaedeutic Medicine, University of Athens Medical School, Laiko General Hospital, 17 Ag. Thoma Street, 11527 Athens, Greece
2. Research Laboratory “Christeas Hall” and Evgenideion Hospital, Athens University Medical School, 5 Doryleou Street, 11521 Athens, Greece
3. Department of Medicine, University of Manchester, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL, UK