The Bronx VA is participating in a research study to explore the beneficial effect of lowering homocysteine levels in patients with chronic renal failure. Chronic renal failure is associated with elevated levels of homocysteine which can be significantly reduced by treatment with folate, B6, and B12. It is thought that elevated levels of homocysteine may lead to vascular events that cause increase risk of arterial thrombosis, coronary disease of cerebrovascular events. This study will follow these clinical endpoints. Dr. Langhoff's basic research interests are HIV-1, Cytomegalovirus, and Polyoma Virus.