Storch and colleagues conducted a multicenter, randomized, double-blind, placebo-controlled, stratified, parallel-group, single-dose trial of coenzyme Q10 (CoQ10) to determine whether nanoparticular CoQ10 is safe and displays symptomatic effects in patients with midstage Parkinson disease (PD) without motor fluctuations. One hundred thirty-one patients were entered into the study. Statistical analysis according to the stratification did not result in significant changes of the primary outcome variable. The frequency and quality of adverse events were similar in both treatment groups. This is the first trial systematically investigating the safety and symptomatic efficacy of high doses of CoQ10 in patients with PD. This study does not support the hypothesis that restoring the impaired energy metabolism of the diseased dopaminergic neurons leads to symptomatic benefits in PD. The study does allow the implementation of future studies with patients with PD to explore the protective effects of CoQ10 at the highest effective dose over a long treatment period.
In a well-focused and detailed review, Minshew and Williams outline the new insights into the biology and behavioral features of autism. The evidence presented supports autism as a disorder of association cortex, both its neurons and their projections. The focus of impaired connectivity has been on white matter, but alterations in functional magnetic resonance imaging activation suggest that intracortical connectivity is also disturbed. These features are discussed and provide a conceptual framework to appreciate the complexities and subtleties of this major disorder of impaired cognition in children.
Markesbery and Lovell point out that free radical–mediated oxidative damage plays a role in the pathogenesis of Alzheimer disease (AD). Previous studies have shown oxidative damage to lipids, proteins, DNA, and RNA in multiple brain regions in late-stage AD. They review the evidence that similar oxidative damage occurs in the brains of patients with amnestic mild cognitive impairment (MCI) who have undergone autopsy. Importantly, early presence of oxidative damage in MCI can serve as a therapeutic target to slow the progression or perhaps the onset of the disease.
Chao and colleagues investigated the skin innervation and pathology of the cutaneous vasculature and their clinical significance in patients with eosinophilia-associated neuropathy (Figure). They report that skin denervation with cutaneous vasculitis is a major manifestation of eosinophilia-associated neuropathy. Editorial perspective is provided by David E. Pleasure, MD.
Skin denervation and motor disability in eosinophilia-associated neuropathy. A, Comparison of intraepidermal nerve fiber (IENF) densities between patients with eosinophilia and age- and sex-matched control subjects. Horizontal lines indicate mean. B, Correlation between IENF density and disability grade. Solid line indicates regression line; dashed lines, 95% confidence intervals.
Miltenberger-Miltenyi et al report the clinical features of 11 patients with Charcot-Marie-Tooth disease (CMT) with neurofilament light chain polypeptide gene (NEFL) mutations and explore genotype-phenotype correlations. They found that no simple genotype-phenotype correlation exists, and they suggest the existence of modifiers in NEFL-related CMT. Editorial perspective is provided by David E. Pleasure, MD. ext-link xlink:href="ned60014"/
Evaluating a family with a frameshift (Leu7fs) mutation in the PMP22 gene with clinical hereditary neuropathy with liability to pressure palsies (HNPP), Li and colleagues studied whether any mutation (missense, frameshift, or truncation) within the coding region of the PMP22 gene ultimately causes HNPP by reducing the amount of PMP22 expressed in myelin. They also studied whether other genes or proteins within the 17p11.2-12 domain contribute to the phenotype of HNPP. They report that PMP22 levels were reduced in the peripheral nervous system in dermal skin biopsy specimens from patients with Leu7fs. They also found that patients with Leu7fs were indistinguishable from patients with HNPP deletion. These results confirm that the phenotypic expression of patients with Leu7fs is identical to HNPP. The reduction of PMP22 is sufficient to cause the full HNPP phenotype.Editorial perspective is provided by David E. Pleasure, MD.
Boecker et al conducted positron emission tomography (PET) measurements using fluorodeoxyglucose F18 (FDG) in patients with Parkinson disease (PD) with and without visual hallucinations. Patients with PD with hallucinations compared with those without were characterized by reductions in the regional cerebral metabolic rate for glucosein occipitotemporalparietal regions sparing the occipital pole.
Epidemiologic studies have reported previously that cigarette smoking is inversely associated with Parkinson disease (PD). Ritz and colleagues extend these findings by studying whether race/ethnicity, sex, education, age at diagnosis, and type of tobacco modify the observed effects of smoking on PD. They found that the risk reductions observed correlated with pack-years smoked and the reduction of risk lessened with years since quitting smoking. The risk reductions were observed for white and Asian patients but were not seen in Hispanic and African American patients. They also found an inverse association for smoking cigars and pipes and chewing tobacco in male subjects.
Baloh et al describe the clinical phenotype and genetic basis of a family with autosomal dominant progressive external ophthalmoplegia and parkinsonism from a Twinkle mutation. Their findings broaden the clinical spectrum of Twinkle gene mutations and further implicate loss of mitochondrial DNA integrity in the pathogenesis of Parkinson disease.
Kraff and colleagues studied whether permutation expansions of the FMR1 gene are associated with parkinsonism in their banked DNA samples associated with their clinic. Three permutation carriers (61, 69, and 80 CGG repeats) were identified from 903 banked samples (0.33%). These findings were not significantly higher than the frequency of permutation alleles in the general population. Thus, broad screening for permutation alleles in PD populations is unlikely to be productive in the absence of additional clinical or family history data suggesting involvement of the FMR1 gene.
Schupf et al examined plasma levels of β-amyloid 42 (Aβ42) and Aβ40 in patients with Down syndrome as a means to determine risk for developing dementia in nondemented participants and for all-cause mortality. They report that elevations in plasma Aβ42 levels are associated with the earlier onset of Alzheimer disease type of dementia and increased risk of death.
Marshall and colleagues examined the relationship between apathy and cortical metabolic rate with positron emission tomography in patients with Alzheimer disease (AD) with and without clinical apathy. They found that apathy in AD is associated with reduced metabolic activity in the bilateral anterior cingulate gyrus and medial orbitofrontal cortex and also in the medial thalamus.
This Month in Archives of Neurology. Arch Neurol. 2007;64(7):932-933. doi:10.1001/archneur.64.7.932