Glial cells have been considered to play unexciting roles in the nervous system compared with neurons. In recent years, however, glia have been rediscovered to be key players in major biochemical and physiologic functions, including integrating neuronal input, modulating synaptic activity, and processing signals related to learning and memory. Glia play a dominant role in several important neurologic diseases, and therapies are being designed to affect glia. This dynamic and rapidly evolving field is reviewed by Kurosinski and Götz.
The diagnostic value of nerve biopsy depends on a number of factors, including the selection of patients, the expertise of the laboratory, and the techniques used. Gérard Said examines the main indications and factors that can increase the usefulness of nerve biopsy. He provides a clear and concise review for the physician, citing the realistic expectations from this procedure.
Coenzyme Q10 was found to be safe and well tolerated at doses up to 1200 mg/d in patients with early Parkinson disease (PD). Of considerable interest, Shults and colleagues, in the Parkinson Study Group, found that subjects assigned to coenzyme Q10 developed less disability than those assigned to the placebo. This convincing study shows that coenzyme Q10 slows the progressive deterioration of function in PD. Mitochondrial therapy may play a direct role in selected patients with PD. Editorial comment is provided by Roger N. Rosenberg, MD.
Unified Parkinson's Disease Rating Scale (UPDRS) scores. The scores for the total UPDRS (last observation carried forward) are expressed as mean (SEM). Higher scores indicate more severe features of Parkinson disease.
Hypocretin-1 levels lower than 110 pg/mL in the cerebrospinal fluid (CSF) are diagnostic for the narcolepsy-cataplexy syndrome, as shown in this study by Mignot et al. Narcolepsy-cataplexy accompanied by low levels of CSF hypocretin-1 is a genuine disease entity, and CSF hypocretin-1 is a highly useful diagnostic marker to identify this segment of patients with sleep disorders.
Brain levels of N-acetylaspartate (NAA) were measured by magnetic resonance spectroscopy to determine axonal integrity in patients with early multiple sclerosis (MS) without clinical disability and in age-matched controls. De Stefano et al show that NAA/Cr (creatine) values were diffusely decreased in patients with very early MS without symptoms of disease. Thus, neuronal and axonal disease begins early in the MS process, perhaps independent of demyelination. Magnetic resonance spectroscopy is a useful clinical indicator to follow the degree of neuronal and axonal pathologic characteristics during the course of disease and a means to evaluate therapeutic intervention.
Kalkers et al report that the rate of development of brain atrophy is largely independent of the course of multiple sclerosis (MS). The degree of atrophy in relapsing-remitting, secondary progressive, and primary progressive MS was found to be equivalent over time. The relentless loss of tissue in MS was not restricted to later phases of the disease; thus, early neuroprotective therapy is important.
Kang and colleaguespoint out that embolism and the low-flow phenomenon are the 2 main stroke mechanisms in internal carotid artery (ICA) occlusive disease. The mechanism of border-zone infarction is still controversial, and diffusion-weighted imaging (DWI) can be useful to define the pattern of the ischemic and infarct lesions. Using DWI, they found 3 distinctive stroke lesion patterns in ICA occlusive disease. The authors emphasize that embolism is a predominant cause of this disease.
Weimar and colleagues define the risk factors, distribution, causes, and prognosis of short- and long-duration transient ischemic attacks (TIAs) and of ischemic stroke, based on their experience at 15 German medical centers. Their study compares and contrasts differences in comorbidity and etiologic factors among patients with TIAs of different durations and ischemic stroke.
Edland et al report, contrary to European and Asian populations, that women in Rochester, Minn, were not at increased risk of incident Alzheimer disease (AD). Their findings were consistent across study designs, which suggests that gender or gender-related exposures do not play a major role in AD causation in populations in the United States. These data are of considerable importance to define gender-related issues involved in the pathogenesis of AD.
Josephs and colleagues report 4 cases of vascular progressive supranuclear palsy (PSP), in which the signs and symptoms were similar to the degenerative form of PSP. Asymmetric signs, falls after 1 year of symptom onset, vascular lesions on magnetic resonance imaging, and an H2 τ haplotype help to differentiate vascular PSP from PSP. Thalamic and basal ganglia infarcts are common in vascular PSP.
Knopman et al evaluated 482 incident cases of dementia and found that overall, in 10% of the patients, the onset or worsening of dementia occurred within 3 months of a stroke. Eleven percent of the incident dementia cases had bilateral gray matter lesions on imaging. The incidence rate of vascular dementia increased steeply with age and was similar in men and women.
Cook et al show that modest brain volumes of subclinical structural brain disease are associated with decrements in cognitive performance within the normal range in healthy subjects. These measurements are important to define the type and degree of structural brain changes in normal aging in contrast with Alzheimer disease and related disorders.
This Month in Archives of Neurology. Arch Neurol. 2002;59(10):1517-1518. doi:10.1001/archneur.59.10.1517