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C Tranchant

Publications and source records attributed to C Tranchant.

At least 55 records · Page 3Linked to original sources
PubMed2000

[Other symptoms of advanced stage Parkinson's disease].

Autonomic dysfunction, neuropsychiatric problems, axial signs and sleep disorders are common complications of advanced Parkinson's disease (PD). Urinary disturbance due to detrusor hyperreflexia and iatrogenic orthostatic hypotension are prominent dysautonomic signs. Depression and anxiety are frequent but can occur exclusively during off periods. A fronto-sub cortical dementia occurs in 30% of PD patients, but anti-parkinsoniens drugs (APD) can cause hallucinations even in non demented PD patients. Axial signs, such as freezing, postural instabily or dysarthria become doparesistant. Insomnia, REM sleep disorders. At least, pain is very frequent. Exact analysis of these signs is important for an adequate treatement: most of them are improved by APD but some of them, like orthostatic hypotension or hallucinations, are increased by these drugs.

Antiparkinson Agents↗
PubMed2000

[Focal dystonia: clinical, etiologic and therapeutic aspects].

Blepharospasm, spasmodic torticoli, and writer's cramp are the most frequently observed forms of focal dystonia. Primary dystonia is often a hereditary condition with a dominant autosomal mode of transmission and variable penetrance. Secondary conditions are generally the expression of a lesion to the basal ganglia due to an iatrogenic cause or exceptionally the inaugural sign of a metabolic disease. The basal ganglia play an important role in the pathophysiology of this reciprocal innervation disorder but progress in genetics may help better understand the different molecular mechanisms involved. Treatment relies on botulin toxin associated with physical therapy depending on the localization. Drug therapy is often disappointing due to minimal efficacy and poor tolerance.

Blepharospasm↗
PubMed2000

[Genetic tests: how far should we go? A case of late-onset Friedreich's disease].

Two sisters developed isolated cerebellar ataxia with pyramidal signs and preservation of reflexes at 49 and 63 years of age. Presence of two abnormal expansions GAA on both allels of the frataxine gene led to the diagnosis of Friedreich ataxia. These cases demonstrate the place of genetic tests in the diagnosis of late onset autosomal recessive ataxia.

Adult↗
PubMed1999

Basis of phenotypic variability in sporadic Creutzfeldt-Jakob disease.

OBJECTIVE: To determine the correlation of clinical and pathologic features with prion protein (PrP) gene polymorphism at codon 129 and with biochemical characteristics of the protease-resistant PrP (PrPres) in sporadic Creutzfeldt-Jakob disease (CJD). METHODS: Clinical data acquisition, determination of the codon 129 genotype of the PrP gene, brain pathologic study, and immunoblot analysis of crude brain extracts were carried out in 14 patients. RESULTS: The first group of 10 subjects showed the classic clinical triad, with dementia, myoclonus, and periodic sharp waves on EEG. None of the subjects had amyloid plaques, but PrP immunoreactivity was of diffuse synaptic type in the cerebellar cortex. All subjects were methionine-methionine at codon 129 and the PrPres had a biochemical profile of type 1 (unglycosylated band of 21.5 kD). A second group of three patients showed cerebellar ataxia and later dementia. Periodic sharp waves on EEG were absent. PrP amyloid plaques predominated in the cerebellar cortex, along with diffuse PrP immunoreactivity. These subjects were valine-valine at codon 129 and had a type 2 PrPres (unglycosylated band of 19.4 kD). In the last patient cerebellar ataxia and dementia appeared simultaneously. Many Kuru-type plaques were present in the cerebellar cortex; many PrP amyloid plaques were present in the basal ganglia. This patient was methionine-valine at codon 129 and the PrPres was of type 1. CONCLUSIONS: The codon 129 genotype is only one of the factors determining CJD phenotype, and the biochemical pattern of PrP has no direct correlation with this phenotype.

Aged↗
PubMed1999

[Spinocerebellar ataxia and polyneuropathy secondary to vitamin E deficiency].

BACKGROUND: Cerebellar ataxia or peripheral neuropathy can be signs of vitamin E deficiency. We report two cases. CASE REPORTS: Two patients developed vitamin E deficiency subsequent to intestinal malabsorption. The first patient had a duodenogastric communication and dilatation of the first jejunal loop. The second patient had deficient pancreas secretion and dilatation of the biliary tree. DISCUSSION: Vitamin E deficiency is generally secondary to acquired or hereditary malabsorption syndrome. It can also occur in the absence of malabsorption by hereditary deficiency in alpha-tocopherol transporter. Vitamin E supplements are required for malabsorption. The etiology work-up of neuropathy or cerebellar ataxia should include vitamin E assay.

Adolescent↗
PubMed1999

Gerstmann-Sträussler-Scheinker disease and the French-Alsatian A117V variant.

Gerstmann-Sträussler-Scheinker disease is a rare familial form of prion disease. This autosomal dominant disorder is constantly associated with a point mutation on the PrP gene. Eight mutations affecting respectively codons 102, 105, 117, 145, 202, 212 and 218, have been so far described. Symptoms are variable and include ataxia and dementia. They generally appear between the fourth and sixth decade. Mean duration of the disease (5 years) is on the whole longer than that of other familial forms of prion diseases. Gerstmann-Sträussler-Scheinker disease is neuropathologically characterized by the presence of numerous multicentric or unicentric PrP amyloid deposits widespread throughout the encephalon. Spongiform change is inconstant. Neurofibrillary tangles have been described in some families. Clinicopathological features show considerable variability. Pathogenesis of amyloidosis and associated lesions as well as factors underlying the phenotypic polymorphism of the disease remain only partially known.

Adult↗
PubMed1998

[Hereditary neurological diseases caused by amplification of triplet repetitions].

NEW TYPE OF MUTATION: Repeated sequences of nucleotide triplets can cause two groups of diseases. GROUP I DISEASES: These diseases result from an expansion of a noncoding portion of a gene which may be repeated more than 1000 times. This group includes several multisystem diseases such as the fragile X syndrome and its variants, Steinert's disease and Friedreich's disease in which nervous system disorders are not always predominant. The molecular mechanism of the cellular disorder is probably related to a nonfunctional abnormal protein. GROUP II DISEASES: Huntington's disease, spinobulbar amyotrophy or Kennedy's disease, dentato-rubo-pallidolusian atrophy and spinocerebellar ataxias 1, 2, 3, 6, and 7 are characterized by local expansion of the coding part of a gene. This low-amplitude expansion always involves the CAG triplet and leads to expression of a protein with an abnormal number of glutamines, producing typical neurodegenerative disease almost exclusively limited to the nervous system. The underlying mechanism of the neuronal suffering is probably the production of an abnormal but functional protein. The causes of this type of mutation remain unclear. PERSPECTIVES: Positive diagnosis is now possible with DNA sequencing. While antenatal diagnosis offers essential information for family genetic counselling there is no perspective of therapeutic propositions for the near future. The problems raised by presymptomatic diagnosis must not be underestimated.

DNA Mutational Analysis↗
PubMed1998

[Gerstmann-Straüssler-Scheinker syndrome].

The Gerstmann-Sträussler-Scheinker syndrome, is a disease transmitted by autosomal dominant inheritance characterized by nonsense mutations of the prion protein associated with specific neuropathological lesions-multicentric amyloid plaques labelled by antibodies directed against the prion protein. This restrictive definition justifies retaining the name of Gerstmann-Sträussler-Scheinder syndrome and excludes observations of hereditary prion diseases without multicentric amyloid plaques and sporadic forms with multicentric plaques. The main feature of these different observations is their polymorphous clinical presentation which varies not only between families with the same mutation but also with a given family. The underlying mechanisms of the phenotypic polymorphism remain uncertain.

Brain↗
PubMed1997

Clinical trial of plasma exchange and high-dose intravenous immunoglobulin in myasthenia gravis. Myasthenia Gravis Clinical Study Group.

We have conducted a trial to randomly assess the efficacy and tolerance of intravenous immunoglobulin (i.v.Ig) or plasma exchange (PE) in myasthenia gravis (MG) exacerbation and to compare two doses of i.v.Ig. Eighty-seven patients with MG exacerbation were randomized to receive either three PE (n = 41), or i.v.Ig (n = 46) 0.4 gm/kg daily further allocated to 3 (n = 23) or 5 days (n = 23). The main end point was the variation of a myasthenic muscular score (MSS) between randomization and day 15. The MSS variation was similar in both groups (median value, +18 in the PE group and +15.5 in the i.v.Ig group, p = 0.65). Similar efficacy, although slightly reduced in the 5-day group was observed with both i.v.Ig schedules. The tolerance of i.v.Ig was better than that of PE with a total of 14 side effects observed in 9 patients, 8 in the PE group and 1 in the i.v.Ig group (p = 0.01). Although our trial failed to show a pronounced difference in the efficacy of both treatments, it exhibited a very limited risk for i.v.Ig. i.v.Ig is an alternative for the treatment of myasthenic crisis. The small sample sizes in our trial, however, could explain why a difference in efficacy was not observed. Further studies are needed to compare PE with i.v.Ig and to determine the optimal dosage of i.v.Ig.

Adult↗
PubMed1997

Neurofibrillary tangles in Gerstmann-Sträussler-Scheinker syndrome with the A117V prion gene mutation.

One patient of a French family with Gerstmann-Sträussler-Scheinker syndrome with the mutation in codon 117 of the prion protein (PrP) gene displayed unexpected neuritic degeneration around PrP plaques and numerous diffuse neurofibrillary tangles, whereas other members did not. The tau profile in this patient's brain was analysed and compared with one from another member of the Gerstmann-Sträussler-Scheinker family as well as with the Alzheimer's tau profile. A panel of well characterised antibodies against both normal tau protein and paired helical filaments-tau protein was used on immunoblots of brain proteins resolved by mono and two dimensional gels. The tau profile in the patient with Gerstmann-Sträussler-Scheinker syndrome without neurofibrillary tangles was normal. The tau profile from the patient with Gerstmann-Sträussler-Scheinker syndrome and neurofibrillary tangles was characterised by a hyperaggregation state of tau protein. This case illustrates the phenotypic heterogeneity of the GSS117 mutation not only from one family to another, but also between members of the same family. In this family, the presence of neurofibrillary tangles is still unexplained, but could be correlated with either the protracted duration of the disease or the old age of the patient.

Adult↗
PubMed1996

[Neuronal ceroid lipofuscinosis. An unknown overload disease].

Neuronal ceroid lipofuscinosis comprises a group of lysosomal diseases transmitted by autosomal recessive inheritance. Often unrecognized, this disease should be evoked in children or adolescents with blindness due to retinal pigmentation, dementia and myoclonal seizures. Retinal pigmentation is lacking in adults. The characteristic feature is an accumulation of fluorescent lipopigments deposited within cells, especially neurons. Histology examination gives the diagnosis based on the ultrastructure of skin biopsies and identification of the disease-specific lysosomal inclusions. The disease can also be identified in children by identification of mutations on genes CLN1, CLN3 and CLN5. The pathophysiology of these diseases remains unknown and treatment is limited to symptomatic care.

Adult↗
PubMed1996

[Amyloidosis, protein conformation dynamics and neurologic diseases].

The abnormal protein which accumulates in the extracellular space in the central nervous system in Alzheimer's disease and prion diseases could result from similar mechanisms. Many studies have demonstrated that the abnormal protein is resistant to proteolytic agents. This resistance is correlated with a modification in the conformation of the protein, inverting the ratio of alpha and beta helix structures. This change in conformation could be the cause of the central nervous system lesions. The mechanism of the modification in conformation could be related to a process of hydrophobisation of the protein resulting from mutation. A hydrophilic amino acid would be replaced by a hydrophobic amino acid or in sporadic forms, modifications in the environment of the peptide may lead to physical and chemical aggressions. Hydrophobisation of the two proteins could later lead to formation of polymers and then insoluble aggregates with the physical and chemical characteristics of the amyloid substance. Polymerisation could be triggered by the formation of protein dimers which would be, in one case, an endogenous protein, PrP, and in the other exogenous proteins coming from the environment.

Alzheimer Disease↗
PubMed1996

[Abnormal central nervous conduction in long-term treatments with retinoids].

INTRODUCTION: Neurological manifestations are uncommon among the undesirable effects of systemic retinoid therapy. We observed a case of axial rigidity imputable to acitretine. Somesthesic evoked potentials were also altered. We therefore searched for such abnormal findings in patients given long-term systemic retinoid therapy. PATIENTS AND METHODS: A neurological exploration was performed in two groups of patients, G1 and G2, with psoriasis and no neurological complaint. The exploration included a physical examination, a study of the somesthesic evoked potentials of all 4 limbs and an electromyogram in case of abnormal findings. There were 8 patients (3 women, 5 men, mean age 56 years, age range 39-71) in G1 treated with systemic retinoids for a mean 140 months (80-185). Cumulative dose was 50 to 280 g with a daily dose of 0.2 to 0.6 mg/kg/day, i.e 20 to 50 mg/d of etretinate or acitretine. In G2, there were 5 subjects (mean age 42 years, range 21-52) with psoriasis (mean duration 20 years range 14-25) who had never been treated with systemic retinoids. RESULTS: Alterations in somesthesic evoked potentials were observed in 7 of the 8 patients in G1. Bilateral disturbances were seen in 6 cases, demonstrating abnormal lemniscal central nervous conduction in the dorsal and/or cervical level in 3 cases and the cervical level alone in 3 cases. There was one asymmetrical case involving the lumbar level on the right and the dorsal and/or cervical level on the right. Only one of the 5 controls in G2 had a minimal unilateral reduction in somesthesic evoked potentials involving the lower limb. Direct effect of systemic retinoids was retained in absence of any other cause due to metabolic, toxic or deficient disorders or spinal compression. CONCLUSION: Long-term use of systemic retinoids induces frequent latent neurological anomalies expressed as lemniscal central nervous conduction. It is hypothesized that pathogenesis involves changes in the lipid composition of the nervous membranes.

Adult↗
PubMed1995

Movement disorders in multiple sclerosis.

Movement disorders (MD), other than tremor, associated with multiple sclerosis (MS) occur infrequently. We report 14 new cases of whom nine had dystonia, three parkinsonism, and two had myoclonus. We also reviewed 135 such cases from the literature. From an analysis of the individual MDs and the site of the lesions described, we conclude that paroxysmal dystonias (tonic spasms), ballism/chorea, and palatal myoclonus can be caused by demyelinating lesions. Parkinsonism, dystonia, and other types of myoclonus, however, often appear to be coincidental.

Adolescent↗
PubMed1995

Localization of Refsum disease with increased pipecolic acidaemia to chromosome 10p by homozygosity mapping and carrier testing in a single nuclear family.

Adult Refsum disease (ARD) is a rare autosomal recessive neurologic disorder associated with the accumulation in blood and tissues of phytanic acid, a natural compound of exogenous origin whose catabolism is impaired in patients. We present here genome wide linkage analysis of an atypical Refsum disease family where L-pipecolic acid level in blood was also increased, suggesting that the patients suffer from a new peroxisomal disorder intermediate between ARD and Infantile Refsum Disease (IRD, a peroxisomal deficiency disease). We were able to demonstrate significant linkage (lod score = 3.6) between Refsum Disease with increased Pipecolic Acidaemia (RDPA) and the interval defined by D10S249 and D10S466 on 10p in this single consanguineous family by combining lod score values obtained from analysis of the multiple affected sibs, haplotype homozygosity and from discrimination between healthy carriers and non carriers based on phytanate oxidase measurements. This illustrates the power of homozygosity mapping with a dense map of microsatellite markers. A similar strategy will allow testing for homogeneity/heterogeneity between RDPA and ARD or the rare complementation groups of IRD.

Cells, Cultured↗
PubMed1995

DNA analysis as a tool to confirm the diagnosis of asymptomatic hereditary neuropathy with liability to pressure palsies (HNPP) with further evidence for the occurrence of de novo mutations.

We performed DNA analysis in four families with hereditary neuropathy with liability to pressure palsy (HNPP). An interstitial deletion of the 17 p11.2 region was found in typically affected patients as well as in as yet asymptomatic patients. The opportunity for an individual genotyping permitted to ascertain a de novo deletion in one clinically affected case with no relevant familial history. DNA analysis thus becomes the most sensitive tool in diagnosing HNPP, since potentially affected patients may lack either informative familial history, or clinical symptoms or even suggestive EMG or histopathological data (tomaculas).

Adolescent↗
PubMed1995

[Neurologic manifestations following accidental exposure to pyralene and its thermal degradation products].

After five young women were exposed to pyralene and its thermal degradation products all developed a rich functional syndrome which could be explained by the traumatic effect of the accident. Nevertheless, in 3 of the women, abnormal somesthetic evoked potentials were observed including 2 with neurological lesions detectable radiologically. Polychlorobiphenyl derivates are toxic for the peripheral nervous system as has been observed in several recent exposure situations. Inversely, any effect on the central nervous system is still under debate.

Accidents, Occupational↗