Public education about the symptoms and risks of transient ischemic attack (TIA) is needed, according to the results of the first large study of the topic. The study, published in the May 13 Neurology, found that only 9% of more than 10,000 people surveyed by phone could define or identify symptoms of TIA. Investigators noted that 3.2% of the study participants had symptoms of TIA but never consulted a physician about them. Among those with a TIA diagnosis, 16% visited a doctor more than a week after symptoms occurred. “People think that because these symptoms go away quickly, they don’t need to worry about them, but that’s definitely not the case,” noted S. Claiborne Johnson, MD, PhD. “People who’ve had a TIA are at high risk of having a stroke, particularly in the first few days after the TIA.”

A study at Mount Everest has shown that acetaminophen is as effective as ibuprofen in treating high-altitude headache. A severe, throbbing headache is the primary symptom of acute mountain sickness, which can have potentially fatal complications characterized by edema in the lungs or brain. Researchers enrolled 74 hikers who reported symptoms of high-altitude headache and asked them to complete a survey for headache symptoms and severity. The hikers were given identical capsules containing either ibuprofen or acetaminophen. Both groups reported similar levels of pain relief and slightly decreased levels of nausea during the two-hour study period, and there were no reports of more serious altitude sickness symptoms. However, the researchers noted that acetaminophen had fewer side effects. The findings appeared in the May Journal of Emergency Medicine.

Sodium concentrations in malignant brain tumors can be measured using MRI, according to a study in the May 1 Radiology. Investigators determined sodium concentrations in malignant tumors, gray matter, white matter, cerebrospinal fluid, and vitreous humor in 20 patients with confirmed brain malignancies and nine controls. Intensities in the sodium images were compared with the signals from a sample with known sodium content, making it possible to directly calculate sodium concentrations. The researchers found sodium concentrations in cancer cells were elevated by an average of 50% compared with other noncancerous tissues or those tissues in subjects with no tumors. Because cancer growth is linked to elevated sodium levels, investigators believe that an easy way to measure them may improve diagnosis and treatment monitoring.

The tau proteins found in Alzheimer’s disease and the alpha-synuclein proteins found in Parkinson’s disease can facilitate each other to form amyloid lesions, according to a report in the April 25 Science. Researchers demonstrated that the alpha-synuclein proteins that form Lewy bodies in Parkinson’s disease can induce tau proteins to form the fiber aggregates found in Alzheimer’s disease. Moreover, interactions between the tau and the alpha-synuclein proteins can dramatically induce the formation of fibrous clumps of both proteins. The investigators believe that these findings may provide insights into the mechanisms underlying both diseases and suggest that therapeutic agents developed for one disease might be efficacious for both.

Researchers at the National Human Genome Research Institute and at the National Institute of Neurological Disorders and Stroke have identified the gene responsible for two related inherited neurologic disorders. The gene responsible for Charcot-Marie-Tooth (CMT) disease type 2D and distal spinal muscular atrophy type V is located on chromosome 7; the investigators speculate that a mutated copy of the gene, called GARS, leads to a reduction in the activity of the gene’s enzyme product. More research into why this disruption produces the specific symptoms of CMT type 2D and distal spinal muscular atrophy type V will be necessary. The study was published in the May American Journal of Human Genetics.

Prenatal exposure to mercury from fish is not associated with impaired neurodevelopment in young children, according to results from the Seychelles Childhood Development Study. Researchers examined 779 mother-infant pairs for the study, which was published in the May 17 Lancet. Mothers reported high fish consumption—12 meals a week, compared with an average of one meal a week in the US—and prenatal MeHg exposure was determined. The investigators assessed neurocognitive, language, memory, motor, perceptual-motor, and behavioral functions in children at age 9. Out of 21 end points, only two tests were associated with methylmercury exposure, suggesting to researchers that there is no evidence of neurodevelopmental risk from prenatal methylmercury exposure solely from fish consumption.

Having a family history of cardiovascular disease is a risk factor for having ischemic stroke at a young age, according to a study in the April 24 rapid access Stroke. Researchers compared 1,000 patients (average age, 65) with ischemic stroke with 800 controls matched for age and sex. Conventional stroke risk factors were assessed, as was family history of heart attack and stroke. When analyzing patients who had a large-vessel stroke prior to age 65, the investigators found that those participants were almost three times as likely as controls to have an immediate family member who had suffered stroke before 65 or a family member who had a heart attack. Those with small-vessel stroke were more than three times as likely to have this family history compared with controls.

Garlic may have a variety of health benefits, including possible protective effects against cancer, Alzheimer’s disease, and cardiovascular disease, according to research presented at the Experimental Biology Meeting in San Diego. Investigators followed nine cardiac patients who were given regular dosages of aged garlic extract and 10 patients who were given placebo. At the end of the study, patients taking the garlic extract had significantly less coronary plaque formation and had lower blood homocysteine levels than did those in the placebo group. Additionally, researchers discovered that aged garlic extract inhibited ß-amyloid generation in neurons, suggesting a possible benefit for patients with Alzheimer’s disease.

More than 10% of residents in nursing homes are taking antiepileptic drugs (AEDs), though only about 5% suffer from epilepsy, reported a study in the May 5 online edition of Annals of Neurology. Researchers studied the records of elderly patients in more than 500 nursing homes around the US. They noted that 8% of the residents had been taking AEDs prior to admission to the homes but were surprised to discover that another 3% were placed on the drugs within three months of admission. Of the patients already taking AEDs, 60% were taking the drugs for seizures. However, only 20% of those placed on AEDs after admission received the drugs to prevent seizures.

Investigators have created a modified adenovirus that more readily attaches to brain tumor cells, thereby infecting them and causing antitumor effects. The therapy, known as Delta-24-RGD, may potentially offer a more effective approach to treating aggressive brain tumors. Delta-24-RGD is designed to reproduce only in cancer cells, killing the host and continuing on to contaminate other tumor cells; when there are no more cancer cells left to infect, the virus itself dies. In repeated experiments with mice, researchers found that 60% of the mice with human glioblastoma tumors implanted in their brains and treated with Delta-24-RGD survived for more than four months, whereas untreated mice lived for less than three weeks. The investigators stress that more research is needed to determine how the human immune system will react to the virus. The study was published in the May 7 Journal of the National Cancer Institute.

Researchers have determined that supplementation with a-melanocyte-stimulating hormone (a-MSH), which modulates inflammatory and immune responses, may be beneficial in patients with brain injury. In a study published in the March 27 Journal of Neurotrauma, investigators measured the levels of a-MSH and of the proinflammatory cytokine tumor necrosis factor-a (TNF-a). Patients with traumatic brain injury or subarachnoid hemorrhage had similar a-MSH concentrations, and the peptide remained consistently low after four days post-injury. There was a negative correlation between plasma TNF-a and a-MSH, leading researchers to believe that “controlling inflammation through administration of an endogenous anti-inflammatory molecule” may reduce the magnitude of the injury.

Fasting every other day can help fend off diabetes and protect neurons as well as or better than either vigorous exercise or caloric restriction, reported a study in the May 13 Proceedings of the National Academy of Sciences. Investigators discovered that mice that were fasted every other day but were allowed to eat unlimited amounts on intervening days had lower blood glucose and insulin levels than either a control group, which was allowed to feed freely, or a calorically restricted group, which was fed 30% fewer calories daily than the control group. The mice were also given the neurotoxin kainate, which damages nerve cells in the hippocampus. The nerve cells of the fasting mice were more resistant to neurotoxin injury or death than nerve cells of the mice on either of the other diets.

A specific nerve cell receptor—vanilloid receptor type 1 (VR-1)—is necessary to initiate the development of inflammatory bowel disease, according to research in the May Gut. The study used three groups of rats and focused on the receptor, which can be activated by heat, acid, and capsaicin, the ingredient that gives chili peppers their heat. The first group of rats was given capsaicin at birth, which inactivated the VR-1 receptors; as adults, the second group was given capsazepine, a VR-1 antagonist which blocks the receptor. The third group of rats served as controls. Investigators induced colitis in all three groups and made detailed studies of the rats’ intestinal tracts. They found that the first two groups of rats showed significantly lower levels of the disease and were protected from its damaging effects, providing evidence that colitis requires neurons containing VR-1.

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