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M Vidailhet

Publications and source records attributed to M Vidailhet.

At least 19 recordsLinked to original sources
PubMed2006

Mixing pro- and antisaccades in patients with parkinsonian syndromes.

Prosaccades and antisaccades were investigated in three groups of patients with parkinsonian syndromes, Parkinson's disease, corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP), and in a control group. Saccade tasks were performed in single-task blocks (i.e. either blocks of prosaccades or blocks of antisaccades) and in mixed-task blocks (i.e. in blocks of randomly interleaved pro- and antisaccades). Saccade latencies and directional errors (misdirected saccades) were analysed in each subject, and we concentrated more specifically on the comparison of error rates in single tasks and in repeated trials of mixed tasks (i.e. mixing costs). The performance of each group in single tasks was largely consistent with previous studies, with normal antisaccade error rates in Parkinson's disease and CBD patients and increased antisaccade error rates in PSP patients. In contrast, a double dissociation was observed in mixed tasks. Parkinson's disease and CBD patients showed a marked increase in prosaccade and antisaccade error rates in repeated trials of mixed tasks, illustrated by increased mixing costs, whereas PSP patients showed similar error rates in single and repeated trials of mixed tasks, i.e. normal mixing costs. These results demonstrate that: (i) antisaccade performances may be differentially affected in mixed tasks and single tasks; (ii) the region of the dorsolateral prefrontal cortex which is crucial for reflexive saccade inhibition does not seem to be involved in the additional processes required in mixed-task conditions; (iii) the study of interleaved pro- and antisaccades may increase the accuracy of the differential diagnosis between these parkinsonian syndromes.

Aged↗
PubMed2006

[Omega 3: is there a situation of deficiency in young children?].

This paper starts with a review of the metabolism of n-6 (omega6) and n-3 (omega3) fatty acids, the resulting eicosanoids (prostaglandins, leucotrienes, and thromboxanes), and the physiological functions they are involved in, with special emphasis on effects during pregnancy (such as possible benefits on fetal growth, prevention of hypertension of pregnancy, and prevention of premature labor). Attention is then turned to the key role for long-chain polyunsaturated fatty acids (LCPUFAs), most notably docosahexaenoic acid (DHA), in central nervous system and retinal cell membrane structure and in cerebral and retinal development. Massive maternofetal transfer of LCPUFAs occurs during the third trimester of pregnancy, so that maintaining an adequate intake of DHA during pregnancy is crucial. Preterm babies must receive sufficient amounts of DHA, either via breast milk or via formula supplemented with LCPUFAs, both of which prevent DHA levels from declining in blood and cerebral phospholipids. These two methods of achieving an adequate DHA intake ensure normal maturation of visual acuity and cognitive function, as shown by randomized controlled trials. Formula supplemented with fish oils rich in n-3 LCPUFAs but lacking a proportionate supply of arachidonic acid (ArA, 20: 4n-6) negatively affects somatic growth, confirming the need for an adequate ArA supply. Eicosapentaenoic acid (EPA) can also exert negative effects. Therefore, the best source of supplemental LCPUFAs may be oil from single-cell algae and microscopic fungi, which contains adequate amounts of DHA and ArA. In full term neonates, strong arguments support LCPUFA supplementation, despite continuing controversy generated by conflicting results from interventional studies. These discrepancies in study results may be ascribable to differences in study design, patient age, intervention duration, assessment tool sensitivity, and LCPUFA sources. In 1996, an amendment to the European Directive on infant formulas and follow-on formulas was developed to authorize LCPUFA supplementation and to specify appropriate ranges. As a result, formulas supplemented with DHA and ArA were introduced on the market. Pregnant and nursing women should be advised to maintain an adequate dietary intake of DHA in order to meet their increased needs and those of the fetus or infant.

Animals↗
PubMed2006

Preservation of cognitive function in dystonia treated by pallidal stimulation.

OBJECTIVE: To assess the effects of bilateral pallidal deep brain stimulation (DBS) on mood and cognitive performance in patients with dystonia before surgery (at baseline, while patients received their usual treatment) and 12 months postoperatively (while patients received neurostimulation and their medications) in a multicenter prospective study. METHODS: Twenty-two patients with primary generalized dystonia were evaluated with tests focused on executive functions. The authors considered the patients' severe disability and selected the following tests: Raven Progressive Matrices 38, Similarities and Arithmetic subtests of the Wechsler Adult Intelligence Scale-R, Grober and Buschke, Wisconsin Card Sorting Test (WCST), verbal fluency, Trail Making Test, and the Beck Depression Inventory. Median age at surgery was 30 years (range = 14 to 54 years), median duration of disease was 18.5 years (range = 4 to 37 years). RESULTS: Before surgery, no patients showed cognitive decline or depression. The surgical procedure appeared to be benign cognitively. One year after surgery, free recall improved. There was a significant reduction in the number of errors in the WCST. No behavioral or mood changes were found. CONCLUSIONS: Bilateral pallidal stimulation has a good benefit-to-risk ratio as it did not negatively affect cognitive performance and mood in primary dystonia, while a significant motor improvement was obtained. Moreover, a significant mild improvement in executive functions was observed, which may have been related either to the surgical treatment or to the marked decrease in anticholinergic drugs.

Adolescent↗
PubMed2006

Randomised controlled trial of essential fatty acid supplementation in phenylketonuria.

OBJECTIVE: The long-chain polyunsaturated fatty acids (LC-PUFA) status of children with PKU is often compromised. LC-PUFA, which are important fatty acids in the development of the CNS, can be synthesised endogenously from the parent essential fatty acids (EFA) provided dietary intakes are adequate. This study was designed to assess the biochemical effect over a 20-week period of a phe-free protein substitute that has been supplemented with a balanced blend of n-3 and n-6 EFAs on LC-PUFA status of children with PKU. DESIGN, SETTING AND SUBJECTS: Fifty three community-living children aged 1-10 years diagnosed with PKU in the newborn period were recruited from seven tertiary centres in the UK and France and randomised to a fat-free control formula or the EFA-supplemented test-treatment formula in an open, prospective study. Forty four children completed the study (20 controls, 24 test-treatments). Fatty acid status was assessed at entry and 20-weeks follow-up. Three day dietary diaries were recorded at 20 weeks' follow-up. The safety, efficacy and palatability of the test-treatment formula were also assessed. RESULTS: The test-treatment group had significantly higher intakes of fat and EFA than the control group. There was a significant between group difference (P=0.04) in increases in median docosahexaenoic acid (DHA) concentrations in erythrocyte phospholipids, which increased by 19% in the test-treatment group and by 0.5% in the control group over the study period. Growth and phe control were satisfactory in all subjects. CONCLUSIONS: Supplementing the diets of children with PKU with a balanced blend of n-6 and n-3 EFA improves DHA status without compromising AA status.

Child↗
PubMed2006

[Resolution of choreic movements associated with HIV encephalitis with anti-retroviral therapy].

INTRODUCTION: Infection of the central nervous system with human immunodeficiency virus (HIV) can be associated with movement disorders. CASE REPORT: A case of chorea during HIV encephalitis which responded well to antiretroviral therapy is reported. Choreic movements disappeared with a decrease of MRI lesions observed in basal ganglia. CONCLUSION: The efficacy of anti-retroviral therapy in choreic movements, a rare syndrome with HIV encephalitis, can be underlined.

AIDS Dementia Complex↗
PubMed2005

Epsilon sarcoglycan mutations and phenotype in French patients with myoclonic syndromes.

BACKGROUND: Myoclonus dystonia syndrome (MDS) is an autosomal dominant movement disorder caused by mutations in the epsilon-sarcoglycan gene (SGCE) on chromosome 7q21. METHODS: We have screened for SGCE mutations in index cases from 76 French patients with myoclonic syndromes, including myoclonus dystonia (M-D), essential myoclonus (E-M), primary myoclonic dystonia, generalised dystonia, dystonia with tremor, and benign hereditary chorea. All coding exons of the SGCE gene were analysed. The DYT1 mutation was also tested. RESULTS: Sixteen index cases had SGCE mutations while one case with primary myoclonic dystonia carried the DYT1 mutation. Thirteen different mutations were found: three nonsense mutations, three missense mutations, three splice site mutations, three deletions, and one insertion. Eleven of the SGCE index cases had M-D and five E-M. No SGCE mutations were detected in patients with other phenotypes. The total number of mutation carriers in the families was 38, six of whom were asymptomatic. Penetrance was complete in paternal transmissions and null in maternal transmissions. MDS patients with SGCE mutation had a significantly earlier onset than the non-carriers. None of the patients had severe psychiatric disorders. CONCLUSION: This large cohort of index patients shows that SGCE mutations are primarily found in patients with M-D and to a lesser extent E-M, but are present in only 30% of these patients combined (M-D and E-M).

Adolescent↗
PubMed2005

Disorganized somatotopy in the putamen of patients with focal hand dystonia.

OBJECTIVE: To explore the selectivity of neuronal somatotopic representation in the striatum of patients with unilateral task-specific dystonia of the right arm. MATERIALS AND METHODS: The authors used fMRI in 14 right-handed dystonic subjects to examine putaminal organization. Subjects performed flexion/extension of the right and left fingers and toes, and contraction of the lips. RESULTS: Compared to healthy volunteer subjects, dystonic subjects had altered somatotopic organization in the left putamen, contralateral to the affected hand. Disease severity correlated with underactivation and decreased distance between right hand and lip representations. In the right putamen, ipsilateral to the affected hand, the somatotopic organization was not altered but disease severity also correlated with reduced distances between limbs. CONCLUSION: In dystonia there may be a dedifferentiation of the normally segregated cortico-subcortical sensorimotor maps in the putamen, which may contribute to the loss of functional selectivity of muscle activity observed in these dystonic subjects.

Adult↗
PubMed2004

[Symptomatic rickets in adolescents].

Although systematic vitamin D supplementation in adolescents remains debated, rickets is nevertheless a well recognized pathology in this age group. Adolescence is an at-risk period because of rapid growth, insufficient calcium intake and/or vitamin D status. Surveys have shown that calcium intake is insufficient (< 1000 mg a day) in 45% of boys and 71% of girls and that vitamin D status is deficient (25-OH-D < 10 ng/ml). The aims of the study carried out by the Calcium Group of the Société Française de Pédiatrie, were to evaluate the frequency of rickets, and to define the criteria for the adolescent population at risk. Forty-one adolescents with rickets were hospitalized between 1985 and 2000. Most of the cases were from the Northern France: 20 from Paris and suburbs, eight from the North-West, four from the North, four from the North-East; five were from the Center of France. The mean age was 13 years and two months for the 28 girls, and 14 years and four months for the 13 boys. Eighty per cent of the adolescents were from immigrant families (33/41): 15 were from sub-Saharan Africa, ten from North Africa, six from Pakistan and two from Turkey. Two thirds of the adolescents were hospitalized in the 2nd quarter of the year. Some adolescents suffered from lower limb pain, 16 had deformations of lower limbs, particularly genu valgum, associated with pain; seven others had either muscle spasms (4), tetany (3). Serum calcium level was low (average 1.84 mmol/l: [1.1-2.5]), and serum 25-OH D level was extremely low. Radiographic characteristics observed were metaphyseal strips on the knees, with condensed edges at times, with the presence of bone demineralization. The treatment combined calcium and vitamin D, and was often administered intravenously when a hypocalcemia was detected. Rickets is not frequent in adolescents, but nonetheless this pathology is not exceptional, and the number of cases is probably under-estimated. Rickets affects immigrant adolescents in particular but nevertheless could also present a certain risk period for the general population.

Adolescent↗
PubMed2004

[Delayed diagnosis of homocystinuria by major deficiency in cystathionine beta synthase].

INTRODUCTION: Homocystinuria due to cystathionine beta synthase (CBS) deficiency is a special type of hyperhomocysteinemia because of its clinical expression (thrombotic events, ectopic lens and mental retardation). It's a rare, hereditary recessive autosomic disease generally diagnosed during childhood. EXEGESIS: Thrombophilia examination in a 50-year-old man found a dramatically increase homocysteinemia. Homocystinuria, profile of plasmatic amino acids and reduced CBS activity, (0.05 microkat/kg protein; N = 1.5 +/- 0.8) confirmed homocystinuria's diagnosis. Family study demonstrates that three siblings suffer from homocystinuria. Vitamin enriched diet with pyridoxin, vitamin B12 and folates induced reducing hyperhomocysteinemia and homocystinuria. CONCLUSION: This case report, original because of the diagnosis age, suggests a hyperhomocysteinemia's screening in patients with recurrent thrombotic events.

Cystathionine beta-Synthase↗
PubMed2004

Factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin.

OBJECTIVE: To identify factors predicting improvement in motor disability in writer's cramp treated with botulinum toxin (BTX). METHODS: 47 patients with writer's cramp were treated with BTX and were evaluated by the same neurologists at initial referral, after each BTX injection, and when the effect of BTX was maximal at the time of the study. Patients and examiners simultaneously and independently rated the efficacy of BTX injections. Self assessment was a global clinical impression of the impact of treatment on writing quality, writing speed, writing errors, and legibility of handwriting; for objective assessment, the examiners used the Burke-Fahn-Marsden (BFM) scale. RESULTS: On the BFM scale, there was a significant improvement (p<0.0001) in both severity and disability scores. Patients with a pronation/flexion pattern of dystonia showed the best and the most sustained improvement. Primary writing tremor was little improved. There was a correlation between the self assessment score and the Burke-Fahn-Marsden score. Benefit was maintained over time CONCLUSIONS: These results have implications for the identification of patients most likely to benefit from BTX injections.

Adult↗
PubMed2003

Candidate gene studies in focal dystonia.

BACKGROUND: Genetic susceptibility factors for focal idiopathic torsion dystonia (F-ITD) are not established. Mutations in the DYT1 gene can cause focal dystonia, and an association with a polymorphism in the D5 receptor gene (DRD5) has been reported but not confirmed. OBJECTIVE: To investigate a possible role of DYT1 polymorphisms, a CA repeat in the D5 receptor gene (DRD5), the human leukocyte antigen (HLA)-DRB locus, and four polymorphisms in the homocysteine metabolism in the pathogenesis of F-ITD. METHODS: Initially, 100 German patients and 100 matched control subjects were investigated. A second French population with 121 F-ITD patients and matched control subjects was also studied. RESULTS: Two polymorphisms of the beta-cystathionine synthase gene were associated with F-ITD in the German population, but this finding was not replicated in a second independent F-ITD patient and control group of French origin. None of the other investigated polymorphisms was associated with F-ITD. The authors failed to confirm a previously reported association with a polymorphism in DRD5. CONCLUSION: No evidence for an involvement of DYT1, DRD5, HLA-DRB, or polymorphisms in the homocysteine pathway in the pathogenesis of F-ITD was found.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMed2003

Adult presentation of MCAD deficiency revealed by coma and severe arrythmias.

We report the case of a 33-year-old man who presented with headaches and vomiting. Soon after admission he became drowsy and agitated, developed ventricular tachycardia and his neurological state worsened (Glasgow coma score 6). Blood analysis showed respiratory alkalosis, hyperlactacidemia (8 mmol/l), hyperammonemia (390 micro mol/l) and hypoglycaemia (2.4 mmol/l). Subsequently, he developed supraventricular tachycardia, ventricular tachycardia and ultimately ventricular fibrillation resulting in cardiac arrest, which was successfully treated. A CT scan of the head revealed cerebral oedema. Whilst in the intensive care unit, he developed renal failure and rhabdomyolysis. The metabolic abnormalities seen at the time of admission normalised within 48 h with IV glucose infusion. Biological investigations, including urinary organic acids and plasma acylcarnitines, showed results compatible with MCAD deficiency. Mutation analysis revealed the patient was homozygous for the classical mutation A985G. This is one of only a few reports of severe cardiac arrhythmia in an adult due to MCAD deficiency. This condition is probably under-diagnosed in adult patients with acute neurological and/or cardiac presentations.

Acyl-CoA Dehydrogenase↗