URSpider alerts us to two separate research reports published in the Proceedings of the National Academy of Sciences pointing to the rapid breakdown of nitric oxide in donated blood as a reason why such blood loses its ability to transfer oxygen, and is sometime implicated in problems such as strokes and heart attacks. Nitric oxide depletion is significant after 3 hours of storage; yet current guidelines allow for storing donated blood for up to 42 days. The article notes: "Several of the researchers, including Stamler, have consulting and/or equity relationships with Nitrox/N30, a company developing nitric oxide based therapies."