ELISAs (Quantikine kits; R&D Systems, Inc., Minneapolis, MN, USA) were used to quantify levels of uMMP-2, uMMP-9, uTIMP-1 and uTIMP-2 as previously reported (Smith et al, 2007 (link), 2008 (link)). Specimens, standards and reagents were prepared according to the manufacturer's instructions. Protein concentration in urine was determined by the Bradford method using bovine serum albumin as the standard as previously described by us (Moses et al, 1998 (link); Roy et al, 2004 (link); Pories et al, 2008 (link); Roy et al, 2008 (link)).