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The synaptotoxic Aβ protein aggregates in the brains of individuals with Alzheimer's disease. Dennis Selkoe and his colleagues identify the size of the Aβ aggregate in the brains of individuals with Alzheimer's disease that is responsible for the deficits of learning and memory that characterize the disease.
Siliciano and his colleagues propose a new index for measuring the antiviral activity of anti-HIV drugs in vitro, which suggests that there are limitations to the efficacy of antiviral drugs on the basis of their mechanism of action. They suggest that the new index is a more accurate way of measuring antiviral activity and that it correlates well with clinical outcomes.
Polycystic kidney disease can be caused by germline mutations in the gene encoding PC2 followed by a second somatic 'hit' in the normal allele. Li and her colleagues now show that TNF-α can also act as a second hit and that disease progression can be blocked by anti–TNF-α treatment in an animal model.