The federal government is ending its contract with a Kentucky nonprofit that it says pressured medical workers to remove organs from patients who were getting better.

Brain immune cells appear to drive reversible sleep loss in mice with Alzheimer’s-like disease. A fire starts in one room, but instead of containing the danger, the sprinkler system floods the entire house. The response causes far more damage than the original threat. Something similar may happen in Alzheimer’s disease. Amyloid plaques, the sticky protein [...]