1. 1Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
2. 2Department of Urologic Surgery, School of Medicine, University of California Davis, Sacramento, California, USA
3. 3Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, California, USA
4. 4Department of Veterans Affairs, Northern California Health Care System, Mather, California, USA