Doctors at Kyoto University Hospital completed an overnight operation Tuesday to transplant a liver into a comatose woman who had donated part of her own liver to her daughter last summer and later suffered liver failure.

The operation, which concluded at 4 a.m., lasted more than 11 hours.

Doctors said the condition of the woman is stable, and that the transplanted liver was functioning properly.

However, the woman will continue to be treated in the intensive care unit with the aid of an artificial respirator, they said, adding that she may have suffered brain damage because she had been in a deep coma.