Study Supports Parkinson’s Treatment That Destroys Part of Brain
Destruction of a small part of the brain called the globus pallidus is an effective treatment for patients with advanced Parkinson’s disease, Dutch researchers say. Many neurosurgeons are already performing the procedure, called a pallidotomy, and the new research provides support for that approach.
Dr. Rob de Bie and his colleagues at the Academic Medical Center in Amsterdam studied 37 patients with Parkinson’s who, despite optimal drug treatment, still showed at least one of the major symptoms of the disorder, such as tremors or stiffness. Half received a pallidotomy immediately and half received the surgery six months later. The latter patients were assessed immediately before treatment so they could serve as a control group for comparison with results from those who had undergone surgery.
The team reported in Saturday’s Lancet that the patients who underwent surgery showed a significant improvement in symptoms as measured on the unified Parkinson’s disease rating scale, with their scores improving from an average of 47 to 32.5. In contrast, the scores of the control group deteriorated over the six-month period, from 52.5 to 56.5.
Another Cause of Retardation Detected
Mental retardation affects about 3% of the population. Some forms are genetic in origin and others are caused by insults in the womb, such as drug abuse, but about two-thirds have an unknown cause. British scientists now say they have found a subtle genetic problem that can account for many of those unexplained cases.
The problem is a rearrangement of segments of DNA on the ends of some chromosomes, the large bundles of genes that carry the human genetic blueprint, according to molecular biologist Samantha J.L. Knight and her colleagues at the John Radcliffe Hospital in Oxford. Large rearrangements of chromosomes have previously been linked to retardation, but the newly discovered changes are much more subtle and do not show up in conventional screening tests, the researchers said.
The team studied 284 children with unexplained moderate to severe retardation and 182 with mild retardation, as well as 75 healthy adults. They reported in Saturday’s Lancet that they found the subtle rearrangements in 7.4% of the children with moderate to severe retardation and 0.5% of those with mild retardation. The rearrangements were not present in any of the healthy adults.
Further studies showed that 10 of the 22 children with the rearrangements had a parent with a symptomless form of the genetic defect. In nine of those families, all other mentally disabled members tested also had the rearrangements.
Breast Cancer Screening From a Blood Test?
Louisiana researchers have found a new marker for breast cancer that could be used to screen women, especially those undergoing treatment for the disease, with a simple blood test. Although the results are still very preliminary, the test could be the breast cancer equivalent of the PSA test used in screening men for prostate cancer.
Drs. Prakash Rao, Madhwa Raj and their colleagues at the Louisiana State University Health Sciences Center discovered increased levels of riboflavin carrier protein, or RCP, in the blood of women with breast cancer. Riboflavin is part of the B-vitamin complex and is essential to cell growth and development.
The team then did blind blood tests on 52 women with breast cancer and 50 healthy women in a control group. They report in the November issue of Cancer Epidemiology, Biomarkers and Prevention that RCP tests detected 88% of tumors in women with early stage tumors and 100% of those in advanced stages.
MS Drug Appears to Reduce Brain Atrophy
Multiple sclerosis patients suffer a significant amount of brain atrophy (shrinkage), even in the early stages of the disease, but that atrophy can be slowed with drugs, according to New York researchers. Most researchers had thought that such atrophy usually occurred only in later stages of the disease.
Dr. Lawrence Jacobs of the State University of New York at Buffalo and his colleagues at Buffalo General Hospital studied 70 MS patients who were treated with interferon beta-1a, trade-named Avonex, and 70 who received a placebo. They used magnetic resonance imaging to measure the amount of brain tissue in relation to the volume of the skull.
The team reported in Wednesday’s Neurology that the patients lost about 0.75% of their brain volume in the first year of the study--even patients at an early stage of the disease--and 0.53% more in the second year. Treatment with Avonex, which had previously been reported to mitigate MS symptoms in the patients, had no effect on atrophy in the first year of treatment, but reduced it by more than half in the second year.
New Form of Interferon Fights Liver Disease
A long-lasting form of interferon alpha-2a is much more effective than conventional forms of the drug in treating hepatitis C infections in patients with cirrhosis of the liver. Cirrhosis is a scarring of the liver that reduces the amount of functioning liver tissue and the flow of blood through the organ. An estimated 4 million Americans are permanently infected with the hepatitis C virus, and about 20% of them will eventually develop cirrhosis. Such patients have proved resistant to treatment.
Dr. E. Jenny Heathcote and her colleagues at the University of Toronto studied 87 hepatitis-C patients with cirrhosis who received the long-lasting drug, trade named Pegasys, and 88 patients who received conventional interferon alpha-2a. They reported Nov. 8 at a Dallas meeting of the American Assn. for the Study of Liver Diseases that 29% of those receiving Pegasys showed a sustained response of undetectable levels of the hepatitis C virus, compared with only 6% of those receiving the conventional drug. Pegasys is injected once a week, while the conventional drug is injected three times per week.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.
