Preliminary evidence published in the March 15 Journal of Molecular Neuroscience suggests that one day doctors may be able to diagnose multiple sclerosis (MS) using a simple blood test. Researchers obtained serum from 25 patients with newly diagnosed relapsing-remitting MS and 25 controls. Serum “was subjected to matrix-assisted laser desorption/ionization-time of flight mass spectrometry following albumin depletion and desalting.” Researchers found a distinct proteomic pattern with three biomarkers at 8637, 8773, and 8818 m/z ratios in patients with MS. Additional studies are needed to identify distinct proteomic patterns that are characteristic of relapsing-remitting, primary progressive, and secondary progressive variants of MS.

Combined treatment with folate and vitamin B¹² is both safe and effective in reducing a risk of hip fracture in elderly patients following ischemic stroke, according to a study in the March 2 JAMA. At least one year following a first ischemic stroke, 628 Japanese patients with residual hemiplegia were randomized to receive folate (5 mg) and mecobalamin (1,500 μg) or a double placebo. At the two-year follow-up, researchers found that plasma homocysteine levels decreased by 38% in the treatment group and increased by 31% in the placebo group. In addition, the number of hip fractures per 1,000 patient-years was 10 and 43 in the treatment and placebo groups, respectively.

Researchers have discovered that insulin and its related proteins are produced in the brain and that reduced levels of both are linked to Alzheimer’s disease. By examining a gene abnormality in rats, researchers found that insulin and insulin-like growth factor type I and type II are expressed in neurons in several regions of the brain. They also found that a reduction in insulin production in the brain contributes to the degeneration of brain cells, an early symptom of Alzheimer’s disease. “These abnormalities do not correspond to type 1 or type 2 diabetes, but reflect a different and more complex disease process that originates in the central nervous system,” researchers said. “This raises the possibility of a type 3 diabetes.” Results of the study are published in the February Journal of Alzheimer’s Disease.

Conformation-dependent immunoassay could be used to determine a postmortem diagnosis of Creutzfeldt-Jakob disease (CJD) with greater accuracy than immunohistochemistry, suggested a study in the March 1 Proceedings of the National Academy of Sciences. Researchers extracted brain tissue from 28 individuals who died of CJD. They found that conformation-dependent immunoassay detected abnormal prions in all of the sampled brain regions, while immunohistochemistry detected abnormal prions in only 25% of the sampled brain regions. The researchers are now exploring ways to use conformation-dependent immunoassay to detect CJD or bovine spongiform encephalopathy in presymptomatic living people and in animals.

Awareness and knowledge about stroke is suboptimal among women, especially among racial/ethnic minorities, according to a report in the March 15 Circulation. Investigators conducted a telephone survey of 1,024 women age 25 and older (68% white, 12% black, 12% Hispanic). They found that only 26% of women age 65 or older reported being well informed about stroke. Furthermore, 37% of women ages 25 to 34 reported that they were not at all informed about stroke, compared with 13% of women ages 45 to 65 and 14% of women age 65 and older. More Hispanic women reported being not at all informed about stroke compared with white and black women. In addition, correct identification of the warning signs of stroke was low among all racial/ ethnic and age groups. The researchers highlighted the need for targeted educational programs about stroke risk and symptoms of stroke in women.

Higher education seems to protect against cognitive decline in older adults, according to a study in the March Neuropsychology. Researchers studied individuals from two age groups—those ages 18 to 30 with 11 to 20 years of education, and those age 65 and older with eight to 21 years of education. Each participant underwent MRI while taking several memory tests. The investigators found that in young adults, more education was associated with less use of the frontal lobes and more use of the temporal lobes. In older adults, more education was associated with less use of the temporal lobes and more use of the frontal lobes. The researchers said these findings suggest that older adults, especially those with higher education, use the frontal cortex as an alternative network to aid cognition.

Investigators have discovered a genetic marker that may lead to a blood test that would predict risk of stroke from a ruptured brain aneurysm. According to a report in the March Journal of Neurosurgery, investigators compared 49 patients with unruptured brain aneurysms with 58 emergency department patients with ruptured aneurysms. They found that people with tandem endothelial nitric oxide synthase gene polymorphisms were 10 times more likely to suffer a stroke from a ruptured brain aneurysm than were people who have aneurysms but lack these genetic variations.

Darifenacin does not have an effect on cognitive function, according to a study in the February Journal of Urology. A total of 129 patients age 65 or older with mild or no cognitive impairment were randomized to receive three of five treatments for overactive bladder: darifenacin controlled release (3.75, 7.5, or 15 mg once daily), darifenacin immediate release (5 mg three times per day), or matching placebo for 14 days. Each treatment period was separated by a washout period of seven days. Investigators found that darifenacin had no effect on memory-scanning sensitivity, speed of choice reaction time, word recognition sensitivity, simple reaction time, digit vigilance speed, or word recognition speed. Memory scanning speed increased in all groups.

Cocaine eye drops may one day be used to diagnose Parkinson’s disease, suggested a research letter in the February 23 JAMA. In order to study sympathetic dysfunction in the pupils as a possible diagnostic marker of Parkinson’s disease, researchers applied 40 μL of 1% phenylephrine solution to both eyes of 38 patients with Parkinson’s disease, 20 controls, and 10 patients with multiple-system atrophy (MSA). After 72 hours, researchers applied 40 μL of 5% cocaine solution to both eyes. Mean pupil diameter was recorded an hour after each solution was applied. Researchers found no difference in dilation caused by phenylephrine between patients with Parkinson’s disease and those in the control or MSA groups. However, dilation caused by cocaine was significantly less than in the control or MSA groups, with little difference in dilation between the control and MSA groups.

African-Americans who are obese and who have had a stroke are at a greater risk of having a second stroke, due to increased risk of a metabolic syndrome, according to a study in the March Archives of Neurology. Investigators determined the body mass index (BMI) of 1,711 African-American patients who were then categorized into six groups: underweight (BMI greater than 18.5), normal weight (BMI of 18.5 to 24.9), overweight (BMI of 25.0 to 29.9), class I obesity (BMI of 30.0 to 34.9), class II obesity (BMI of 35.0 to 39.9), and class III obesity (BMI less than 40.0). They found that a metabolic syndrome was present in 26.1% of men and 34.7% of women with class I obesity, in 29.4% of men and 31.3% of women with class II obesity, and in 43.3% of men and 29.1% of women with class III obesity.

Axonal defects may occur earlier than previously thought in the development of Alzheimer’s disease, according to a study in the February 25 Science. Researchers identified axonal defects in mouse models of Alzheimer’s disease that preceded known disease-related pathology by more than one year and also observed similar axonal defects in the tissue of patients with early-stage Alzheimer’s disease. They found that “impairing axonal transport by reducing the dosage of a kinesin molecular motor protein enhanced the frequency of axonal defects and increased amyloid-beta peptide levels and amyloid deposition.” A reduction in a microtubule-dependent transport may stimulate production of beta-amyloid precursor protein, resulting in the development of senile plaques and Alzheimer’s disease.

Researchers might eventually be able to use MRI to screen patients for Alzheimer’s disease before the onset of symptoms, according to a report in the March 20 online edition of Nature Neuroscience. By injecting mice with a compound known to bind to amyloid plaques, researchers were able to create images with contrast high enough to identify the plaques. Imaging amyloid plaques in patients would offer doctors a chance to diagnose and treat Alzheimer’s disease years earlier than is possible at present. The team added that “this approach could be used in longitudinal studies in mouse models of Alzheimer’s disease to search for biomarkers associated with amyloid beta pathology as well as to track disease course after treatment with candidate medications.”

Researchers have developed a measure of neurobehavioral functioning during coma from severe brain injury that predicts the recovery of consciousness up to one year after injury with up to 86% accuracy. The Disorders of Consciousness Scale (DOCS) consists of eight subscales: social knowledge, taste and swallowing, olfactory, proprioceptive and vestibular, auditory, visual, tactile, and testing-readiness. The investigators evaluated military veterans and civilians older than 18 who were unconscious after a severe brain injury. They found that DOCS accurately detected improvements, declines, and plateaus in neurobehavioral functioning among unconscious patients. Results of the study were published in the January/February Journal of Rehabilitation Research and Development.

An anesthetic regimen of midazolam, sodium thiopental, and isoflurane used during surgery on pregnant women does not seem to be injurious to the fetal brain, according to a report in the March 9 online edition of the Journal of Cerebral Blood Flow and Metabolism. Researchers exposed pregnant sheep to the anesthetic regimen and found that four hours of general anesthesia “produced an initial increase in fetal systemic oxygenation and a sustained increase in fetal cerebral oxygenation.” These increases are likely due to the effects of isoflurane, they said. When comparing sheep exposed to anesthesia with those not exposed, researchers found no negative effects of anesthesia on the fetal brain. Because exposure studies are difficult to conduct in humans, large, retrospective, epidemiological studies are needed to determine whether there are cognitive or developmental problems in children whose mothers received anesthesia during pregnancy, they concluded.

NR