1 Department of Laboratory Medicine, Cliniques Universitaires St-Luc and Université Catholique de Louvain, Brussels, Belgium.
2 Diabète et Nutrition, Pôle de Recherche en Endocrinologie, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires St-Luc and Université Catholique de Louvain, Brussels, Belgium.
3 Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy.
4 Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy.