SACRAMENTO, Calif. (AP) — Two California neurosurgeons who infected brain-cancer patients with bowel bacteria in an unsuccessful effort to save their lives have resigned their positions at the University of California, Davis.

Dr. J. Paul Muizelaar and Dr. Rudolph J. Schrot resigned after a university investigation concluded their experimental treatment violated the school's faculty code of conduct.

The Sacramento Bee ( reports that the doctors disagree with the findings but decided to resign because they doubt an appeal would prompt a fair hearing.

Muizelaar, who headed the university's neurosurgery department, left in June.

Schrot is leaving at the end of this month.

The three patients who were infected each granted permission for the treatment.

Two patients died soon after. The other died more than a year later.

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