A new study done by Japanese researchers and published in the 'Journal of Clinical Investigation' today showed that stem cells harvested from monkey embryos and implanted in the brains of adult monkeys reversed some of the symptoms of Parkinson's disease in the monkeys.

While doctors leading the study cautioned that the results are preliminary, it is hopeful that similar techniques can be eventually used on humans to treat Parkinson's Disease and other conditions.

The stem cells are used to replace the damaged neurons that cause the trembling and other symptoms of Parkinson's. The transplanted cells actually grew in the brains of the monkeys and reversed the damage.

Doctor William Langston of the Parkinson's Institute in Sunnyvale, California was intrigued by the results of the study. 'Clearly the study reported here will advance research aimed at validating the use of stem cells to treat neurodegenerative disease,' he said.

Still, the results were preliminary and some of the new brain cells did not survive well.

The controversy over stem cells in this country is ongoing. The Bush administration has placed sharp limits on embryonic stem cell research, claiming it is immoral because of the use of human embryos. Meanwhile, many researchers claim that the limits placed on their work will prevent the United States from being at the forefront of the next great hope in medical research.