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Thickening of the cardiac valves leads to congestive heart failure, chest pain, sudden loss of consciousness and often death. Experiments in mice now link this condition to dysregulation of an endogenous inhibitor of angiogenesis (1151–1159).
HIV causes a chronic infection that overwhelms the immune system and leads to T-cell exhaustion. Three groups now report that a signaling molecule that dampens immune responses may tucker out the T cells (1198–1202).