“Episodic marijuana use may represent a risk factor for stroke in childhood, particularly in the posterior circulation,” according to a report in the April Pediatrics. Investigators reported on three of eight male adolescent patients with ischemic cerebellar stroke after the use of marijuana. For the cohort, three patients received CT scans, one received MRI, one received cerebral arteriography, cerebellar biopsy was conducted on one patient, and autopsies were performed on two patients. In a retrospective case and chart review, the researchers found that “three adolescent males had similar presentations of headache, fluctuating level of consciousness or lethargy, visual disturbance, and variable ataxia after self-administration of marijuana.” These patients developed primary cerebellar infarctions within days after the exposure “that could not be attributed to supratentorial herniation syndromes and only minimally involved brainstem structures,” the authors reported. “Early recognition of the cerebellar stroke syndrome may allow prompt neurosurgical intervention, reducing morbidity,” they concluded.

Researchers at Albany Medical College in New York successfully induced neural stem cells to generate large numbers of neurons in animal studies. The stem cells, when cocultured with endothelial cells from blood vessels in a mouse model, produced large amounts of both neurons and glial cells, whereas previous studies had produced large quantities of glial cells but few neurons, the investigators explained. They conjectured that the endothelial cells may play a role in the production of neural stem cells and ultimately in the production of neurons. The technique could prove to be an important step towards developing treatments for Alzheimer’s disease, Parkinson’s disease, and other neurologic injuries, the researchers noted. Their findings were published in the April 1 Science.

The FDA has approved Apokyn (apomorphine) as an injectable drug for treating Parkinson’s disease patients during episodes of hypomobility. The effectiveness of apomorhine in the acute symptomatic treatment of recurring episodes of hypomobility associated with advanced Parkinson’s disease was established in three randomized, controlled trials. On average, patients participating in these trials had had Parkinson’s disease for 11.3 years and were being treated with levodopa and at least one other agent, usually an oral dopamine agonist. Apomorphine must be taken with an antiemetic drug. It must not be taken with the 5HT3 antagonists because the combination can lead to very low blood pressure and loss of consciousness. It is intended for subcutaneous injection. Apokyn is marketed by Bertek Pharmaceuticals.

Targeted preoperative antiplatelet therapy can significantly reduce carotid endarterectomy patients’ postoperative risk of thromboembolism without increasing the risk of bleeding, according to a study in the March 30 Circulation. British researchers randomized 100 carotid endarterectomy patients on routine (150 mg) aspirin therapy to 75 mg clopidogrel or placebo on the night prior to surgery. Postsurgical analysis revealed that “clopidogrel produced a small (8.8%) but significant reduction in the platelet response to adenosine 5’-diphosphate”—a marker of high risk of thromboembolism—“while conferring a 10-fold reduction in the relative risk of those patients having greater than 20 emboli in the postoperative period,” they reported. Clopidogrel increased the time from flow restoration to skin closure, but there was no increase in bleeding complications or blood transfusions, they noted.

Wine is protective against Alzheimer’s disease, researchers from the Washington Heights Inwood-Columbia Aging Project reported. After four years of follow-up, 260 of 980 community-dwelling individuals 65 and older developed dementia. After adjusting for age, gender, apolipoprotein E (APOE) epsilon4 status, education, and alcoholic beverage consumption, the investigators found that only intake of up to three daily servings of wine was associated with a lower risk of Alzheimer’s disease. Intake of beer, liquor, and total alcohol was not associated with a lower risk of Alzheimer’s disease. Further analysis revealed that the association was confined to participants without the APOE epsilon4 allele. The study was published in the April Journal of the American Geriatrics Society.

vioxx (rofecoxib) has been approved by the FDA for the treatment of migraine pain. The drug was previously approved for arthritis pain. It is the only COX-2–specific inhibitor approved to relieve migraine pain and migraine symptoms. The new indication was based on two double-blind, placebo-controlled multicenter studies that enrolled approximately 1,600 patients who were treated for a single migraine attack of moderate to severe intensity. A single dose of rofecoxib (25 mg or 50 mg) provided significant migraine headache pain relief compared to placebo. Both doses also reduced the incidence of migraine symptoms including photophobia, phonophobia, and nausea. Vioxx is marketed by Merck & Co, Inc.

RIM1-alpha—a protein involved in the release of neurotransmitters in the brain—is essential to learning and memory in mice, according to researchers at the University of Texas Southwestern Medical Center in Dallas. “We found that when you delete this molecule, the mice essentially become incredibly stupid,” the investigators said after comparing the behavior of normal mice and three sets of genetically altered mice, each of which was missing a specific protein involved in the release of neurotransmitters. Of these, only the mice lacking RIM1-alpha were unable to learn the location of an escape platform in a pool of water despite repeated attempts over several days. “The brain was able to compensate for the loss of these other two proteins, but it was not able to compensate for the lack of RIM1-alpha,” the researchers said. The results of the study were published in the April 7 Neuron; the investigators hope further study will lead to potential treatments for neuropsychiatric disorders.

A study testing the effect of statin treatment on ß-amyloid metabolism in humans questioned whether this method of Alzheimer’s disease prevention is in fact effective. Researchers reported that patients treated with statins had plasma cholesterol levels that were reduced by 56%, but there was no significant change in the levels of plasma ß-amyloid. Thus, if statins have a protective effect against Alzheimer’s disease, it does not come from the processing of plasma amyloid precursor protein, they said—though they acknowledged that statins may still affect amyloid precursor protein processing in the brain or be protective by other mechanisms. The study was published in the March Archives of Neurology.

Recombinant growth hormone eliminates the risk of Creutzfeldt-Jakob disease, but not the risk of mortality from “potentially preventable” conditions in patients who received pituitary-derived growth hormone, according to a report in the April Journal of Pediatrics. A cohort of 6,107 pituitary-derived growth hormone recipients (treated between 1963 and 1985) was studied. Investigators reported 433 deaths in the cohort—nearly four times the expected number. Twenty-six cases of Creutzfeldt-Jakob disease were found, but hypoglycemia and adrenal insufficiency “accounted for far more mortality than Creutzfeldt-Jakob disease,” the investigators said. A quarter of all deaths were sudden and unexpected, they noted. “The large number of potentially preventable deaths in patients with adrenal insufficiency and hypoglycemia underscores the importance of early intervention when infection occurs in patients with adrenal insufficiency, and aggressive treatment of panhypopituitarism,” they concluded.

Carotid artery intima-media thickness—a predictor of heart attack and stroke—is significantly higher in patients with HIV infection compared with healthy controls, according to a study by researchers at the University of California, San Francisco. Published in the April 6 Circulation, the study found that HIV infection was an independent predictor of carotid artery intima-media thickness. Age, LDL-cholesterol levels, and smoking were also independent predictors. The duration of protease-inhibitor therapy was not associated with thicker carotid intima-media thickness, the investigators reported. Carotid intima-media progression was greater among patients with HIV at one-year follow-up; progression was associated with older age, Latino race, and a history of a low CD4 cell count, the researchers reported. “Our findings suggest that it would be reasonable to consider HIV infection a cardiac risk factor. Other cardiovascular risk factors … need to be aggressively treated in HIV patients—even if it means changing their HIV medications,” the authors concluded.

“Patent foramen ovale is not associated with increased risk of subsequent stroke or death among medically treated patients with cryptogenic stroke,” according to a practice parameter compiled by the Quality Standards Subcommittee of the American Academy of Neurology. The new guideline refuted the current thinking that persons with a patent foramen ovale who have had a stroke are at greater risk of having a second stroke. In a review of two Class I and one Class II studies, investigators also found an increased risk of recurrent stroke in patients with patent foramen ovale and atrial septal aneurysm (relative risk, 2.98) in medically treated patients younger than 55, but not an increased risk of a composite of stroke and death. The guideline encouraged neurologists to communicate about future health risks with patients who have had a stroke and are receiving aspirin or warfarin therapies. There was a consensus that patients should know that the presence of a patent foramen ovale does not necessarily signify an increased risk for subsequent stroke compared to stroke patients without atrial abnormalities.

Curry may be protective against brain oxidation, researchers reported at the annual scientific conference of the American Physiological Society. Curcumin, the yellow pigment in curry, was previously determined to be neuroprotective due to its ability to induce hemeoxygenase-1 protein—a fundamental defense mechanism for neurons exposed to an oxidant challenge —on hippocampal neurons. The investigators exposed rat type 1 astrocytes and hippocampal neurons to various concentrations of curcumin and found increased expression of hemeoxygenase-1 protein at both cytoplasmic and nuclear levels on immunofluorescence analysis. Higher concentrations of curcumin (50 to 100 µM) caused a substantial cytotoxic effect with no changes in hemeoxygenase-1 protein expression, they noted. Additional in vivo and in vitro studies are necessary to determine whether curcumin can be used as a preventive agent against acute neurodegenerative conditions.

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