Over 30% were suicidal at some point, and a few experienced problems with physical movement known as parkinsonism.

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Mr. Levine also has a form of Parkinsonism, related to Parkinson's disease, that, along with the medication used to treat it, has contributed to shaking in his left hand.

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The stem cells were taken from these and, in a laboratory culture, and body chemicals used to "persuade" them to shift, stage by stage, from this state into the type of brain cells that their Parkinsonism mice were lacking.

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