1. Department of Histology and General Embryology, University La Sapienza, 00161 Rome, Italy
2. Department of Experimental Medicine, University La Sapienza, 00161 Rome, Italy
3. Departments of Orthopaedics and of Cell Biology, Yale University, New Haven, Connecticut 06510
4. Department of Experimental Medicine, University of L'Aquila, 00161 L'Aquila, Italy
5. Department of Medical Physiopathology, University La Sapienza, 00161 Rome, Italy
6. Istituto Dermopatico dell'Immacolata, 00167 Rome, Italy
7. Division of Endocrinology and Metabolism, University of Texas Health Science Center, San Antonio, Texas 78284-7877
8. Department of Pathology, University of Texas Health Science Center, San Antonio, Texas 78284-7877