1 Department of Physiology, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece.
2 Fourth Department of Internal Medicine, School of Medicine, University Hospital Attikon, National and Kapodistrian University of Athens, Haidari, 12462 Athens, Greece.
3 Joint Academic Rheumatology Program, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece.