[1] Univ Sassari, Inst Internal Med, I-07100 Sassari, Italy
[2] Dept Pathol, Pittsburgh, PA USA
[3] Osped SS Annunziata, Lab Pluridisciplinare, Sassari, Italy
[4] Univ Sassari, Dept Vasc Surg, I-07100 Sassari, Italy
[5] Baylor Coll Med, Houston, TX 77030 USA
[6] VA Med Ctr, Houston, TX USA