Urine samples were placed on ice, aliquoted and then centrifuged at 12000 g for 5 min at 4uC. Measurements of urinary albumin were performed on supernatant fractions, using an ELISA kit (Exocell Inc., Philadelphia, PA, USA). Results were corrected for urinary Cr concentration, using a kit specific for human Cr (Creatinine Companion, Exocell Inc.).