Volume 6 Issue 1, January 2010

Gene therapies have entered clinical trials for several neurological disorders, most notably Parkinson disease. A study in a nonhuman primate model of Parkinson disease has reported motor deficit improvements following the use of a lentiviral vector to restore extracellular dopamine levels. A clinical trial is now underway to evaluate the effectiveness of this approach in humans.

Clinical trials comparing surgical and endovascular interventions for carotid artery stenosis have produced inconclusive and conflicting results. Companion studies now provide data on the long-term efficacy and durability of these therapies for treating carotid artery stenosis. What do these findings tell us about the relative merits of the two techniques?

Prion diseases are fatal and untreatable neurodegenerative brain diseases that can mimic other brain illnesses. Therapies for these conditions are most likely to work in the early stages of the disease, but no simple, early diagnostic tests are currently available. New findings, however, indicate that brain MRI could aid diagnosis.

Genome-wide association studies (GWAS) have uncovered over two dozen candidate Alzheimer disease susceptibility genes; however, the results of these studies showed limited overlap. Two independently performed GWAS involving cohorts from Europe and the US have now identified three additional putative Alzheimer disease genes that show modest but remarkably consistent effects across data sets.

Ultrasound-based technologies are emerging as promising noninvasive approaches to treat brain disorders. Researchers in Switzerland have shown that chronic pain can be alleviated through thermal ablation of thalamic tissue by high-intensity focused ultrasound.

Traditionally, researchers have studied brain function in terms of physiological responses to environmental demands, yet much of the brain's energy is actually devoted to intrinsic neuronal signaling, or 'dark energy'. Zhang and Raichle describe the imaging strategies that are being used to explore intrinsic neuronal activity and examine the relationship between alterations in the functional architecture of intrinsic activity and neurological disease.

Movement disorders are frequently encountered in the clinic, but establishing the correct diagnosis can be problematic, especially if the clinical presentation is complex. In this article, Adbo et al. provide a practical guide to pattern recognition in movement disorders and discuss how a clinically classified syndrome might be translated into an etiological diagnosis.

The DNA repair enzymeO⁶-methylguanine-DNA methyltransferase (MGMT) antagonizes the effects of alkylating agents, and its expression is associated with resistance to cancer therapy based on these compounds. Weller et al. consider the prognostic and predictive value of MGMT gene silencing in gliomas and describe the assays that are commonly used to evaluate MGMT status, focusing particularly on MGMT promoter methylation, which is the key mechanism of MGMTgene silencing.

Practicing clinicians can experience difficulty in differentiating between Parkinson disease and idiopathic normal pressure hydrocephalus. In this article, Morishita and colleagues consider the clinical features that might differentiate Parkinson disease from idiopathic normal pressure hydrocephalus, and highlight the usefulness of the levodopa challenge test in distinguishing between these two conditions.