Problem: To treat HIV-related neurological problems (such as cognitive disorder, dementia and opportunistic infections), doctors need to get drugs into the brain. But the gatekeeper protecting your gray matter, the blood-brain barrier (BBB), keeps out all but the most essential elements. (Some HIV meds do cross the BBB, but the pickings are slim and the drug levels achieved in the brain aren't high enough to reverse HIV's damage.)

Possible solution: Researchers at Cornell's College of Veterinary Medicine have found that a drug called Lexiscan can open the BBB door, allowing large molecules like those of HIV meds to enter. Only tested in mice so far, the experimental strategy is expected to work in humans too.