1. Department of Medical Sciences, Azienda Ospedaliera Universitaria Senese, Siena, Italy
2. Department of Clinical Medicine and Surgery, Federico II University, Naples, Italy
3. Department of Medicine Surgery and Neurosciences, University of Siena, Siena, Italy
4. Experimental Research Laboratory on Bone Metabolism, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Istituto Auxologico Italiano, Milan, Italy