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The country’s top drug regulators on Wednesday pushed back on claims they move too slowly in approving new stem cell treatments and sought to temper expectations for the field’s potential to benefit patients, emphasizing the hazards and the unknowns that persist with developing such therapies. ... The authors make their argument in the staid language befitting both government regulators and academic journals. But their message is clear: Let’s all take a deep breath on the stem cell hype. (Joseph, 11/30)

A nonprofit research group is giving scientists a new way to study the secret lives of human cells. On Wednesday, the Allen Institute for Cell Science provided access to a collection of living stem cells that have been genetically altered to make internal structures like the nucleus and mitochondria glow. (Hamilton, 11/30)