A urine sample taken at the doctor’s office may be the first step in determining Alzheimer’s disease risk. As reported in the June Archives of Neurology, a urine test can reliably detect isoprostanes, fatty acids that are formed as the result of free radical damage associated with mild cognitive impairment, a recognized precursor to Alzheimer’s disease. Within four years of initial diagnosis of mild cognitive impairment, up to 50% of people progress to Alzheimer’s disease. Researchers found significantly higher levels of isoprostane in the cerebrospinal fluid, blood, and urine of patients with mild cognitive impairment and Alzheimer’s disease than in control subjects. Remarkably, the samples taken from the mild cognitive impairment subjects and the control subjects differed only in respect to their isoprostane levels.

Beta-blockers provide significant protection to the brain and its functions when given prior to or during coronary artery bypass surgery, according to an article published in the June 13 Journal of Cardiothoracic and Vascular Anesthesia. Researchers analyzed the medical records of 2,575 patients who underwent bypass surgery at Duke University during a three-year period. They found that only 3.9% of patients receiving beta-blockers suffered adverse neurologic events, compared with 8.2% of those who did not receive the medication. For the most severe events, stroke and coma, the beneficial effect of beta-blockers was even more telling—a 1.9% rate of adverse effects for those taking the drugs and a 4.3% rate for those who did not. This study is the first to examine the effects of beta-blockers on the brain when given before or during surgery.

Magnetic resonance imaging (MRI) scans of the brain may detect Alzheimer’s disease decades before clinical onset, according to results of a study published in the May 28 Neurology. By analyzing postmortem MRI brain scans of 56 participants of the Nun Study, researchers have found that shrinkage of the hippocampus occurs very early in the disease process. Investigators believe that the ability to identify those at high risk for Alzheimer’s disease will be an important step in its eventual prevention. The findings suggest hippocampal volume could be valuable in predicting who is likely to develop Alzheimer’s disease, but the researchers emphasize that application of such imaging will require further study.

Investigators at Yale University have developed a synthetic peptide that promotes new nerve fiber growth in the damaged spinal cords of laboratory rats. The rats received the peptide for four weeks through a catheter inserted into the spinal canal. Multiple nerve fibers regenerated, allowing the rats to walk better. The results confirmed which molecules block axon regeneration in the spinal cord and showed that a peptide can facilitate new growth. The findings, published in the May 30 Nature, could lead to the reversal of functional deficits resulting from brain and spinal cord injuries, stroke, and degenerative diseases. Researchers are now seeking to find whether the compound is safe and effective for human use.

Researchers have discovered that xenon gas may act as a neuroprotectant, helping to prevent damaged nerve cells from dying by blocking the effects of a glutamate receptor, according to a report in the June Anesthesiology. Based on preclinical trials, researchers think it could have human applications, possibly leading to treatments for people with nerve damaging illnesses, such as strokes, and brain and spinal cord injuries. “At present, nerve cells cannot regenerate when they die, but by using xenon we may be able to stop those cells from dying in the first place,” said anesthesiologist Mervyn Maze, MB, ChB. So far, xenon has been found effective only in preclinical trials; clinical trials in the USA and UK will begin shortly.

Women with polycystic ovaries, a common gynecologic disorder, develop stiff arteries that may increase their risk of heart disease and stroke, according to a report in the June 18 Circulation. Researchers used ultrasound to measure arterial stiffness and compliance in the common carotid artery and internal carotid artery in women with healthy ovaries, those with polycystic ovaries, and those with polycystic ovary syndrome. On average, women with polycystic ovary syndrome had arteries nearly twice as stiff as the arteries in women with healthy ovaries, indicating the possibility of more extensive artery disease throughout the body.

Researchers at the University of Minnesota and the University of Virginia have demonstrated the role of the cerebellum during motor skill learning and discovered that the cerebellum does not contribute to learning itself but is engaged primarily in the modification of performance. This distinction between learning activity and performance activity represents an important step toward understanding how the brain processes information. The investigators found they could train subjects to learn a movement task but prevent them from changing their performance by asking them to simultaneously perform a distractor task at the same time. After the distractor was removed, the subjects completed the task, showing evidence of having learned the movements. An MRI detected brain activity in the cerebellum during the performance of learned motor skills but not during the learning phase itself, it was reported in the June 14 Science.

Investigators have determined that some patients with sarcoidosis may have small fiber neuropathy, according to findings in the June 15 Lancet. The study, conducted from August 2000 to February 2001, examined 70 patients with chronic severe sarcoidosis. Some patients with sarcoidosis experience unexplained pain and dysesthesia, although this aspect of the disorder has received little attention. Peripheral pain and paresthesias were present in 77% and 65% of the patients, respectively. A skin biopsy from seven patients showed reduced intraepidermal nerve fiber density compared with the six controls, confirming the presence of small fiber neuropathy. According to the researchers, future studies need to consider the pathophysiology and treatment of this previously unrecognized feature of sarcoidosis.

Researchers have genetically engineered a mouse to show pathologic symptoms similar to those of patients with multiple system atrophy, also known as Shy-Drager syndrome. Investigators hope this model will help to develop new drugs to treat the disease. Although little is known about its pathology, multiple system atrophy is characterized by oligodendroglial cytoplasmic inclusions composed of alpha-synuclein. Since normal mature oligodendrocytes do not express alpha-synuclein, the pathology of multiple system atrophy may arise from this aberrant expression of alpha-synuclein. To test this theory, investigators implanted the human gene for the alpha-synuclein protein into the mouse genome and found insoluble inclusion bodies of the protein in the mouse’s oligodendrocytes. The study was published in the June EMBO Reports.

Cognitive rehabilitation programs should be incorporated into comprehensive care programs for patients with focal seizures, according to research findings published in the June Epilepsia. Investigators assigned 50 patients with focal seizures and attention impairments to either a retraining method group, a compensation method group, or a control group. Neuropsychological outcomes and self-reported quality of life were evaluated at pretraining, post-training, and after a six-month follow-up. Both the retraining method group and the compensation method group reported improved quality-of-life and neuropsychologic outcomes. Because attention plays a vital role in daily activities, cognitive rehabilitation can assist patients with attention impairment and complaints, particularly those with active epilepsy.

Researchers have determined that exposure to selective serotonin reuptake inhibitors (SSRIs) is not associated with an increased risk of intracerebral hemorrhage or ischemic stroke. Because SSRIs have been connected to bleeding complications, there has been concern as to whether SSRIs also increase the risk of hemorrhagic stroke. The study, in the June Stroke, identified 659 patients who had an intracerebral hemorrhage and 2,717 patients diagnosed with ischemic stroke between January 1994 and December 1999, and matched them to 40,000 controls. Researchers found that the risk of intracerebral hemorrhage in users of SSRIs was 1.0 compared to nonusers, while the risk of ischemic stroke among SSRI users was 1.1 compared to nonusers, showing no association between SSRI use and stroke.

Results of a new brain scan study may offer proof of fibromyalgia’s physical roots, according to findings in the June Arthritis & Rheumatism. Researchers used functional MRI on 16 fibromyalgia patients and 16 controls, scanning their brains for more than 10 minutes while a device applied various calibrated pressures to the base of their left thumbnail. Investigators found that it took only mild pressure to produce self-reported feelings of pain in the fibromyalgia patients, while the control subjects tolerated the same pressure with little pain. In addition, patients experiencing pain showed increased activity in 12 areas of the brain, although they shared only eight of these areas in common with the control subjects.

Small amounts of botulinum toxin type A are proving effective at treating debilitating headaches, and a success rate as high as 92% for patients who didn’t respond to headache medications has been reported. At a press conference prior to the annual meeting of the American Headache Society, Todd Troost, MD, stated, “When it is effective, the need for daily medications or acute medicines for severe attacks is significantly reduced or eliminated.” For the study, researchers evaluated 134 patients with migraine headaches, tension headaches, or chronic daily headaches. The subjects had one to four treatments every three months and were asked to evaluate the results on a five-point scale. Improvement was reported in 84% of patients overall; among patients who had four treatments, 92% reported improvement, with a mean score of 4.3. The researchers believe that botulinum toxin type A can be less expensive and will have fewer side effects than many medications used to prevent headaches.

Sudden, unexpected death in children with epilepsy is rare, unless there is a severe neurologic disorder accompanying the epilepsy, according to findings in the June 1 Lancet. A population-based cohort study conducted in Nova Scotia followed 692 children diagnosed with epilepsy between 1977 and 1985 and found that 26 (3.8%) died. Of the 26 deaths, only four were unexpected—the causes of death were listed as suicides in two, homicide in one, and sudden death in epilepsy in one. The remaining deaths resulted from severe disorders that caused functional neurologic deficit. Researchers hope to alleviate worries in families of children with epilepsy by demonstrating that if children with epilepsy have no other serious disorders, their risk of death is the same as that of the general population.

A 30-year-old woman who had lost 40 pounds in 11 months by following a slimming diet by Herbalife International of Europe (herbal supplements plus dietetic meals) developed ataxia and nystagmus and had great difficulty walking and balancing. A neurologic examination revealed the diagnosis of Wernicke’s encephalopathy, stemming from a deficiency of thiamine. “There is a possibility that a decreased intestinal absorption of thiamine, facilitated by the use of an herbal preparation, may have caused a deficiency of the vitamin in the patient,” said GianPietro Sechi, MD. The woman responded well to daily thiamine injections and, in the months that followed, had no neurologic complaints. The report appeared in the June 11 Neurology.

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