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PARKINSON'S DISEASE NEWS 5th September 2009 - New research RETINAL STEM CELLS DISAPPEAR AFTER SURGERY FOR PARKINSON'S DISEASE Neurology [2009] Sep 2. [Epub ahead of print] (Farag ES, Vinters HV, Bronstein J.) Complete abstract Retinal pigment epithelial cells have been found to disappear after being used in a form of surgery intended for use in Parkinson's Disease. For years, the use of implanted stem cells have been claimed to have the potential to rid Parkinson's Disease. One of these means is the use of RPE (retinal pigment epithelium) cells. These cells are found in the eyes and can also produce dopamine, the substance whose deficiency causes Parkinson's Disease. A 68-year-old man underwent surgical implantation of 325,000 RPE cells in Spheramine (gelatin microcarriers) for the treatment of Parkinson's Disease. He happened to die six months after the surgery took place. This enabled the researchers to see what happened to retinal stem cells after surgical implantation. Over 99.9% of the cells had disappeared after only six months. Implanted cells simply failed to survive. A previous study using the same methods demonstrated only a moderate benefit for six months. For more details see the Complete abstract. Despite different forms of stem cell surgery now being carried out in countries around the world, there is not even one study in the entire medical literature showing that anybody has ever been rid of Parkinson's Disease by this means. In order to refer to this article on its own click here. 2nd September 2009 - News report PIMAVANSERIN FAILS CLINICAL TRIAL FOR PARKINSON'S DISEASE Pimavanserin, a drug in development for psychosis related to Parkinson's Disease failed to have any beneficial effect in clinical trials. Psychotic episodes, such as hallucinations and delusions, sometimes occur in Parkinson's Disease. The drug was being developed by Arcadia and Biovail. For more information go to Biovail. Parkinson's Disease is largely due to insufficient dopamine. Psychosis appears to be due to almost the opposite - an excess or an accumulation of dopamine. This is why anti-psychotic drugs can cause Parkinson's Disease symptoms, and why Parkinson's Disease drugs can sometimes cause symptoms of psychosis. Pimavanserin is a "5-HT 2A receptor inverse agonist". Biochemically that could have no effect on the excessive dopamine found in psychosis. So the failure of Pimavanserin in clinical trials is almost predictable. The psychosis sometimes experienced in Parkinson's Disease is normally due to the excessive use of dopaminergic drugs. So a reduction in the use of those drugs is a more rational approach than using an additional drug to combat the effects of dopaminergic drugs. In order to refer to this article on its own click here. Rayilyn Brown Director AZNPF Arizona Chapter National Parkinson Foundation [log in to unmask] ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn