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hi all beware whiffs of the "tragic" and "devastating" science "reporting" by Gina Kolada in the NYT last year janet ----------------------------------------------------------------------- Retinal cell transplants show promise in relieving Parkinson's symptoms (04-17) 22:27 PDT DENVER (AP) -- Scientists say a handful of patients with advanced Parkinson's disease are showing notable improvement following the infusion of retinal cells into the damaged movement centers of their brains. The experimental procedure, which was limited to six patients, remains years away from government approval for clinical use, said neurologist Ray Watts, who is directing the study at Emory University in Atlanta. But patients' motor functions have improved and the intensity of their debilitating muscle tremors have been reduced by as much as 40 percent, Watts said Wednesday at the annual meeting of the American Academy of Neurology. The first transplant was made 21 months ago. While preliminary, the method so far shows none of the shortcomings and disturbing side effects of another experimental technique that uses neurological cells harvested from aborted human embryos. "If anything, this is an alternative," Watts said "So far, it appears to be safe and well-tolerated." The researchers went to a donor bank and took retinal pigment epithelial cells from human eye tissue. RPE cells are not brain cells, but they still produce dopamine, a neurotransmitter that controls movement. Patients with Parkinson's disease gradually lose motor control and suffer from increased stiffness, tremors and speech difficulties as their own dopamine-producing cells die. To compensate for these losses, researchers grew millions of duplicate RPE cells and mixed them with microscopic gelatin beads. The retinal cells, which normally are fixed in layers of the retina in the back of the eye, cling to the beads for stability. Surgeons drilled five small holes into a portion of the brain's movement control center known as the putamen; the holes were made in a grad pattern to diffuse the transplanted cells. Some 350,000 cells were infused in each patient. Within a month, researchers said the transplanted cells apparently began to produce dopamine and the patients' symptoms improved and they required less assistance, especially in the mornings. Meanwhile, the field's leading transplant method using hard-to-find brain tissue from aborted fetuses is still troubled by a devastating clinical setback last year. That approach pioneered during a University of Colorado trial has been successful in some patients for as long as eight years. But in 15 percent of the patients, the embryonic cells have generated excessive levels of dopamine, resulting in uncontrolled jerking movements and other side effects that researchers described as tragic. Those patients cannot have their transplants reversed and instead have been treated with medication. At least three have received electrical stimulators that work like pacemakers for the brain, said the study's director, neurologist Curt Freed. He said the new patients were receiving fewer fetal cells and those were being transplanted into more specific parts of the brain's movement center to minimize potential side effects. He said the best transplant candidates are younger than 60 and already respond well to drug therapy, qualifications that limit the procedure's effectiveness in the general population. Freed said his study's most remarkable patient is a 58-year old electrician who received the transplant three years ago. The man was working in the World Trade Center on Sept. 11 when the first hijacked jetliner struck. Freed said the man walked down 34 flights, ran several blocks, then walked three miles to Times Square without medical assistance. JOSEPH B. VERRENGIA, AP Science Writer http://www.sfgate.com/ janet paterson: an akinetic rigid subtype, albeit perky, parky pd: 55/41/37 cd: 55/44/43 tel: 613 256 8340 email: [log in to unmask] smail: 375 Country Street, Almonte, Ontario, Canada, K0A 1A0 a new voice: http://www.geocities.com/janet313/ ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn