Anti-GM1 antibodies are not associated with cerebral atrophy in patients with multiple sclerosis.

OBJECTIVES: The aim of this study was to correlate the brain atrophy with serum levels of anti-GM1 antibodies in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: Plasma sample from 52 patients with RRMS and 65 healthy controls were examined for anti-GM1 antibodies. Patients with RRMS underwent to MRI study with automated method called SIENAX that calculated an estimate of gray matter (GM(V)) and white matter (WM(V)) volumes. RESULTS: The percentage of RRMS patients with increased anti-GM1 was 37.8%. Elevated levels of anti-GM1 antibodies did not correlate with brain atrophy. CONCLUSIONS: Anti-GM1 antibodies do not represent a marker of axonal damage in patients with RRMS.

Anti-GM1 ganglioside antibodies in Parkinson's disease.

OBJECTIVES: To determine whether anti-GM1 antibodies are increased in Parkinson's disease (PD). METHODS: Serum immunoglobulin M (IgM) and IgG anti-GM1 antibodies were detected by enzyme-linked immunosorbent assay (ELISA) in 147 patients with PD and in 186 age-matched normal control subjects. Sera were assayed at initial dilution of 1:800 for IgM and 1:200 for IgG and were considered positive at absorbance values exceeding the value of 0.05 for IgM and 0.1 for IgG. RESULTS: Forty patients with PD (27.2%) had sera positive for IgM anti-GM1 antibodies, whereas only five normal controls (2.7%) resulted positive (P < 0.0001). Most of patients (75%) with positive sera had a tremor-dominant form of PD. Only two patients with PD (1.4%) and none of normal controls had sera positive for IgG anti-GM1 antibodies. CONCLUSION: A consistent portion of parkinsonians, mainly with a tremor-dominant form of PD, may have increased circulating IgM anti-GM1 antibodies.

Body weight, levodopa pharmacokinetics and dyskinesia in Parkinson's disease.

We conducted a pharmacokinetic study in 164 patients with sporadic Parkinson's disease (PD) to address the relationship between body weight and levodopa pharmacokinetics. Patients underwent an oral acute levodopa test with 250 mg levodopa and pharmacokinetic variables were further assessed. Plasmatic levodopa area under the curve (AUC-l) and body weight were significantly and inversely correlated. Women were significantly lighter and more dyskinetic than men, and had greater AUC-l values. Our data suggest that during long-term treatment, lighter PD patients, especially women, may receive a greater cumulative dosage of levodopa per kilogram of body weight. This could explain gender differences for the development of levodopa-induced peak-dose dyskinesias observed during the course of the disease.

Plasma levels of vitamin E in Parkinson's disease.

Oxidative stress has been implicated as a major contributor to selective neuronal death in Parkinson's disease (PD). Vitamin E is an antioxidant that may protect the brain from free radical-induced oxidative damage. It is, therefore, reasonable to hypothesize that low levels of vitamin E concentrations may increase the risk of developing PD. To elucidate the possible role of vitamin E in the pathogenesis of PD, we assessed the plasma levels of vitamin E, measured by high-performance liquid chromatography (HPLC), in 54 patients with PD. Vitamin E concentrations were also assessed in 93 age and sex matched normal individuals. The mean plasma levels of vitamin E did not differ significantly between these two groups (22.5+/-8.15 &mgr;mol/l for PD patients and 21.0+/-7.9 &mgr;mol/l for controls). The results of our study suggest that plasma vitamin E concentrations do not play a major role in the pathogenesis of PD.

Vitamin E deficiency due to chylomicron retention disease in Marinesco-Sjögren syndrome.

We report on 2 brothers (aged 19 and 12 years) with Marinesco-Sjögren syndrome who also had very low serum vitamin E concentrations with an absence of postprandial chylomicrons. The molecular study ruled out ataxia with isolated vitamin E deficiency, abetalipoproteinemia, and hypobetalipoproteinemia. The electron microscopy of the intestinal mucosa was consistent with a chylomicron retention disease. We speculate that both chylomicron retention disease and Marinesco-Sjögren syndrome are related to defects in a gene crucial for the assembly or secretion of the chylomicron particles, leading to very low serum levels of vitamin E.

Loss of long-duration response to levodopa over time in PD: implications for wearing-off.

OBJECTIVE: To determine the modifications of the long-duration response to levodopa in PD over a 1-year period. BACKGROUND: The development of predictable motor fluctuations in PD has been attributed mainly to modifications over time of the short-duration response to levodopa, whereas the role of the long-duration response has not been widely investigated. METHODS: In 17 patients with PD the authors examined prospectively both the short-duration response and the long-duration response to levodopa under standardized conditions on two different occasions separated by a period of approximately 1 year (11.7 +/- 3.6 months). RESULTS: At the end of the follow-up period, the short-duration response increased in magnitude but did not change significantly in duration. A total of 24% of patients lost the long-duration response 1 year after their first examination, but a sustained long-duration response could be reestablished by shortening the interdose interval for levodopa intake. Moreover, the duration of the long-duration response after discontinuation of treatment became significantly shorter during 1 year. CONCLUSION: Modifications of the long-duration response may have a pivotal role in generating a fluctuating response, and suggest that therapeutic strategies based on maintenance of the long-duration response should be sought to avoid the appearance of motor fluctuations.

EcoRI-RFLP of the Apo B gene: a study in a sample group from south Italy.

EcoRI restriction analysis at codon 4154 of the Apo B gene was performed in a sample of 90 subjects from southern Italy (sample S), using total blood cell DNA amplified by PCR. A group of 46 subjects from northern Italy (sample N) was also investigated for comparison. Southern Italians showed an incidence of the R2 allele (absence of the cutting site) twice as high as that found in northern Italians (48 v. 21%). By ASPCR the mutation which abolishes the restriction site was confirmed as being G----A at the first base of the 4154 codon of the Apo B gene (Glu----Lys) in both S and N samples. By studying the variability of cholesterolaemia among different EcoRI genotypes in the S sample, it was estimated that the average effect of the R2 allele is to lower serum cholesterol by 8.5 mg/dl.

XbaI-RFLP of the APOB gene in a sample group from southern Italy.

The XbaI Restriction Fragment Length Polymorphism (RFLP) of the APOB gene at codon 2488 was investigated in a sample group from Southern Italy (165 subjects), taken from a population characterized by a low average level of cholesterolemia. The X2 allele (presence of XbaI cutting site), that in several groups was found to be associated with increased cholesterolemia, showed in Southern Italians a frequency of 39% which is significantly (P much less than 0.001) lower than that found in the majority of the Caucasoid groups so far tested (50%). However, an analysis of both cholesterol and APOB serum levels performed in a sample of 82 subjects, homogeneous for sex and age did not reveal any significant association between lipidemic parameters and APOB-XbaI genotypes.

Hb F-Cosenza or G gamma 25(B7)Gly----Glu: a new fast-moving fetal hemoglobin variant.

A fast-moving gamma chain variant was discovered in the cord blood of a newborn during a screening program carried out in the northern region of Calabria, Southern Italy. The structural analysis showed a Gly----Glu substitution at position 25 of the G gamma chain indicating a new fetal hemoglobin variant that was named Hb F-Cosenza.