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PITTSBURGH (AP) – An appeals court has upheld the conviction of a former University of Pittsburgh medical researcher in what prosecutors said was the 2013 cyanide poisoning death of his wife.

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Defense attorneys had asked the Pennsylvania Superior Court for a new trial for Robert Ferrante, who was convicted of first-degree murder in 2014 and is serving a life sentence.

Allegheny County prosecutors said he killed Autumn Klein by putting cyanide in her energy drink, which text messages show he urged her to drink to enhance fertility.

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The defense attorney cited the transplant of Klein’s liver after she died and argued it would have been unable to be donated had she been poisoned. The appeals court said Thursday the transplant wasn’t new evidence.

Eyster vowed an appeal to the state Supreme Court.

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