Biomedical subjects

J Pouget

Publications and source records attributed to J Pouget.

At least 73 records · Page 4Linked to original sources

PubMed1999

[Superficial siderosis of the central nervous system].

We report five cases of superficial siderosis of the central nervous system. All patients developed progressive deafness and cerebellar ataxia associated with pyramidal tract signs or mental deterioration. The cerebrospinal fluid examinations usually revealed an elevated protein level, without other abnormalities. Magnetic resonance imaging typically showed a hypointense rim around the cerebral and cerebellar hemispheres, the brainstem and the spinal cord on T2-weighted images. A definite source of bleeding was only found in two patients. The literature on superficial siderosis is reviewed. The etiologies and the pathogenesis are discussed.

Adult↗

PubMed1999

[Epilepsy in an adult with chromosome 22q11 micro-deletion].

Chromosome 22q11 deletion is a frequent genetic anomaly, recently discovered, responsible for DiGeorge syndrome and velo-cardio-facial syndrome. The spectrum of clinical features is large: dysmorphic syndrome, mental delay, conotroncal cardiopathy; neurologic manifestations are not rare. Case report is a 28 year old man who presented a symptomatic epilepsy caused by stroke, associated with conotroncal cardiopathy, mental delay, hypocalcemia and facial dysmorphy. A cytogenetic study confirmed the chromosome 22q11 deletion.

Adult↗

PubMed1999

[Posture and gait modulation using sensory or attentional cues in Parkinson's disease. A possible approach to the mechanism of episodic freezing].

Parkinsonian patients have difficulties for walking as well as for adapting their posture following a voluntary or automatic movement that will disturb their equilibrium. Furthermore, in Parkinson's disease, the patients can suffer for motor blockades (or freezing) in which the movement is like frozen during its execution. These motor blockades can occur during gait initiation, turning round, as well as during the walking through apertures or small passages, but with a high variability as inter-individual as intra-individual. Cognitive, attentional or sensory stimulation--especially visual information--can interact directly on these motor blockades, either positively inhibiting them or negatively inducing them. The different modulation factors of locomotion as well as posture, in Parkinsonian patient and in healthy elderly, and the special case of the motor blockades in Parkinsonian patients are reviewed here. We also examine the effects of L-DOPA with respect to each of these factors. In the conclusion, the modulation of gait, posture, and freezing are discussed in term of mechanisms involved or hypothesis recently proposed.

Adaptation, Physiological↗

PubMed1998

Acute transverse myelitis and primary urticarial vasculitis.

We report the case of a 56-year-old man with severe normocomplementaemic primary urticarial vasculitis for 16 years. Nine and 11 years after the onset of the symptoms, he developed two severe neurological complications, seizure and transverse myelitis, that must be attributed to the vasculitis. Transverse myelitis has been reported in other systemic diseases, particularly lupus erythematosus, but this is the first case of transverse myelitis complicating urticarial vasculitis.

Acute Disease↗

PubMed1998

Adenosine and migraine.

BACKGROUND: Adenosine is a powerful natural vasodilator that participates in the control of cerebral and meningeal blood flow. In this context, it could be involved in the pathophysiology of migraine, since it was previously reported that intravenous adenosine can precipitate crises in migraine patients. METHODS: We have investigated circulating adenosine levels in 12 patients suffering from migraine without aura, during crises and in crisis-free periods, and have compared the levels noted to those of a population of 10 controls. To determine if there are interactions between adenosine and serotonin, we examined the effect of adenosine and antagonists on the uptake and the release of (14C) serotonin by platelets. RESULTS AND CONCLUSION: We have reached a dual conclusion: 1) during migraine headaches there is an increase (mean 68%) in circulating adenosine levels and this increase may participate in cephalalgia; 2) activation of A2 receptors by adenosine causes a dose-dependent serotonin uptake by platelets. This inhibition of uptake could participate in the rapid elimination of serotonin in migraine sufferers. As a result of this, the use of adenosine antagonists could be an effective complementary treatment for migraine.

Adenosine↗

PubMed1998

Mapping of a complicated familial spastic paraplegia to locus SPG4 on chromosome 2p.

Autosomal dominant familial spastic paraplegia (AD-FSP) is a degenerative disorder of the central motor system characterised by progressive spasticity of the lower limbs. AD-FSP has been divided into pure and complicated forms. Pure AD-FSP is genetically heterogeneous; three loci have been mapped to chromosomes 14q (SPG3), 2p (SPG4), and 15q (SPG6), whereas no loci responsible for complicated forms have been identified to date. Here we report linkage to the SPG4 locus in a three generation family with AD-FSP complicated by dementia and epilepsy. Assuming that both forms of AD-FSP are caused by mutations involving the same FSP gene, analysis of recombination events in this family positions the SPG4 gene within a 0 cM interval flanked by loci D2S2255 and D2S2347.

Adult↗

PubMed1998

Brain metabolic profiles obtained by proton MRS in two forms of mitochondriopathies: Leber's hereditary optic neuropathy and chronic progressive external ophthalmoplegia.

The status of brain metabolism has been evaluated using monovoxel short echo time (20 ms) 1H magnetic resonance spectroscopy in 6 patients with two forms of mitochondrial disorders without clinical cerebral involvement: 2 patients with Leber's hereditary optic neuropathy (LHON) and 4 patients with chronic progressive external ophthalmoplegia (CPEO). Patients with LHON displayed normal spectra. In all patients with CPEO, the brain metabolic profiles were abnormal, with no single uniform pattern. No typical cerebral metabolic profile was found even when these disorders were classified either by syndrome or by biochemical defect. No lactate signal was detected. The metabolic alterations observed in CPEO patients contrasted with the absence of clinical signs of encephalopathy. The absence of a typical metabolic profile reflects the large variability in the clinical expression of biochemical defects in mitochondriopathies, and the lack of convergence between genetic deletions, biochemical anomalies and clinical syndromes.

Adult↗

PubMed1998

Novel muscle chloride channel (CLCN1) mutations in myotonia congenita with various modes of inheritance including incomplete dominance and penetrance.

Autosomal-dominant and -recessive myotonia congenita are caused by mutations in the skeletal muscle voltage-gated chloride channel gene (CLCN1). We searched for mutations in this gene in 20 unrelated families with myotonia congenita. We identified 11 different mutations in 10 families. Two of five new mutations (Ala313Thr and Ile556Asn) were both autosomal recessive and dominant with either reduced penetrance or incomplete dominance. Mutations in the CLCN1 gene do not therefore necessarily behave in a classic Mendelian manner.

Adult↗

PubMed1997

Mutations in the X-linked form of Charcot-Marie-Tooth disease in the French population.

The present study reports eight additional mutations in the connexin32 gene associated with the X-linked form of Charcot-Marie-Tooth disease. One of these mutations was found twice in two apparently unrelated families. This form of the disease is demyelinating and dominant. However, patient selection for mutational screening should not be limited to these criteria since presentation can either be familial or sporadic, and some patients may be incorrectly classified as suffering from an 'axonal' form. These new mutations complete our previously published work on 12 other mutations and enable meaningful observation in a representative sample of the French population. Mutations are found in all regions of the gene. The most frequently observed mutations were those affecting arginines and mainly involved CpG sequences. Compared with other sources, some of the mutations were present at a higher frequency in the French population.

Adolescent↗

PubMed1997

SMN gene analysis of the spinal form of Charcot-Marie-Tooth disease.

The spinal form of Charcot-Marie-Tooth disease (spinal CMT) is a rare genetic disorder of the peripheral nervous system, the genetic basis of which remains unknown. To test the hypothesis that a defect of survival motor neuron (SMN), the determining gene for spinal muscular atrophy (SMA), would result in spinal CMT, 18 unrelated spinal CMT patients were studied. Nine of them were sporadic cases and the other nine belonged to unrelated autosomal dominant pedigrees. None of the 18 patients showed deletions involving SMN exons 7 or 8, the most frequent gene alteration found in SMA. In addition, haplotype analysis in two large autosomal dominant pedigrees showed that the 5q13 locus was not segregating with the spinal CMT locus. Therefore, neither the sporadic nor the familial cases of spinal CMT are associated with a SMN gene deletion, nor are the familial cases linked to the 5q13 region, indicating that this neuropathy is genetically different from SMA.

Charcot-Marie-Tooth Disease↗

PubMed1997

Long term follow up of multifocal motor neuropathy with conduction block under treatment.

Eighteen patients (15 men, three women; age range 30 to 71 years, mean 45.8 years) with multifocal motor neuropathy treated with high dose intravenous immunoglobulin (IVIg) were evaluated for nine to 48 months (mean follow up 25.3 months). The median time between onset of multifocal motor neuropathy and treatment was 5.8 years. The dose of IVIg was 0.4 g/day for three to five days. The interval between each treatment was determined for each patient by the evaluation of the effect of the first course. Muscle strength was evaluated by a computerised analyser. Clinical improvement was seen in 12 patients treated with IVIg (67%). Isometric strength increased from 32% to 97% (mean 54.5%) of the initial value. Functional scales corroborated these findings. No clear predictive factors of response to IVIg was found except the presence of high titres of IgM anti-GM1 antibodies. Often, patients needed repeated courses of IVIg to maintain the improvement. In two patients, IVIg infusions were stopped without signs of relapse after one year. Four patients were initially treated with prednisone (1 mg/kg/day), without any clear improvement. Five patients with no response to IVIg or who were IVIg dependent were treated with cyclophosphamide, but only one showed improvement. These results show the long term benefits and safety of IVIg in multifocal motor neuropathy but also the transient effect of this expensive treatment in most patients.

Adult↗

PubMed1997

Molecular analysis of the androgen receptor gene in Kennedy's disease. Report of two families and review of the literature.

We have performed a molecular analysis of the androgen receptor gene in two families with suspected Kennedy's disease (spinal and bulbar muscular atrophy, SBMA) with the aim of making a firm diagnosis of the disease. The 2 patients studied were sporadic cases. Both presented clinical signs compatible with the diagnosis of SBMA: limb and facial muscular weakness of adult onset progressing toward muscular atrophy. Clinical signs of partial androgen insensitivity syndrome usually observed in SBMA were present only in patient 2. Enzymatic amplification of the CAG repeat region of exon 1 of the androgen receptor gene was performed on genomic DNA. PCR products were submitted to agarose or acrylamide electrophoresis for size evaluation. Precise determination of the CAG number was performed by direct sequencing of purified amplification products. Androgen receptor gene analysis was also performed in 2 sisters of patient 1 and in the mother, sisters and daughter of patient 2. Androgen receptor-binding activity was also determined on cultured genital skin fibroblasts of patient 1. Analysis of PCR products showed in both patients a single band that was much larger in size than the control. The expansion of the CAG repeat number was confirmed by direct sequencing: the exact number of CAG was 47 in patient 1 and 42 in patient 2 (n = 12-32). The 2 studied sisters of patient 1 did not present the abnormal fragment, demonstrating they are not carriers for the disease. Conversely, the mother, sisters and daughter of patient 2 presented both normal and mutated alleles. The migration of the labelled PCR products on a sequencing gel revealed a meiotic instability of expanded CAG repeat in family 2. Moreover, patient 1 had a decreased androgen-binding capacity on cultured genital skin fibroblasts. In both families, analysis of the androgen receptor gene permitted us to diagnose SBMA in the patients and to establish the carrier status in siblings. These results correspond to the literature data and confirm the usefulness of CAG repeat evaluation in the diagnosis of Kennedy's disease. They highlight the relationship between the androgen receptor and motoneuron growth, development and regeneration.

Base Sequence↗

PubMed1997

Phenotypic expression of diabetes secondary to a T14709C mutation of mitochondrial DNA. Comparison with MIDD syndrome (A3243G mutation): a case report.

OBJECTIVE: To analyze the clinical and biochemical features of a recently described point mutation of mitochondrial DNA associated with diabetes. This mutation, characterized by a T14709C transition of a highly conserved nucleotide in the region coding for the glutamic acid tRNA, is heteroplasmic. RESEARCH DESIGN AND METHODS: The phenotypic expression in the insulin-requiring diabetic proband from the pedigree was compared to that of diabetic probands from three families with the classic A3243G mtDNA mutation (maternally inherited diabetes and deafness [MIDD] syndrome). The same investigations to evaluate pancreatic neurosensorial and muscle involvement were performed in all four patients. RESULTS: The natural courses of the diabetes and the hearing defects were not different between the two mutations. The patient with the 14,709 mutation, however, exhibited a milder alteration of pigmentary epithelium of retina and a much more severe muscle involvement, as attested by the clinical expression and the concurrent anomalies of muscle energy production evidenced by 31P magnetic resonance spectroscopy, confirming the profound impairment of oxidative processes. CONCLUSIONS: This novel mutation has to be added to the other known mtDNA anomalies in order to ascribe some diabetes suspected to arise from mitochondrial defects to this nosological framework.

Adult↗

PubMed1997

[Late onset myasthenia: 34 cases in patients over 65 years of age].

This study, a retrospective view of 34 patients with myasthenia gravis, compared the course of the disease for patients with onset before 65 and after 65 years. 70% of those under 65 were female while 55.8% of those over 65 were male. Bulbar symptoms were more frequent in older patients. Only 3 patients had another immune disease (rheumatoid arthritis, diabetes mellitus, thyroid pathology), and two a thymoma. All patients were treated with anticholinesterases. Prednisone was used in 44% of cases and rarely Azathioprine. In our cases and in the review of the literature there is no significant difference between age groups except for the sex ratio and the outcome in the older group in case of thymoma or respiratory failure.

Aged↗

PubMed1997

[Variable and recurrent ptosis and ophthalmoplegia in chronic polyradiculoneuritis].

Fluctuating ptosis and diplopia are typical features of myasthenia gravis. This report describes four patients who developed these symptoms and in whom the investigations have demonstrated typical features of chronic inflammatory polyradiculoneuropathy. Ptosis and ophtalmoplegia were in most the cases unilateral and were sometimes painful. The evolution was fluctuant with episodic exacerbations. These unusual clinical features have responded like other features of CIDP to corticosteroids or to intravenous immune globulin but relapses are always possible. We did not find in the serum of three patients anti-GQ1b IgG antibodies as previously found in Miller-Fisher syndrome or in Guillain-Barré syndrome associated with ophtalmoplegia. Considering these results, on can argue that other immune mechanisms are involved.

Adrenal Cortex Hormones↗

PubMed1997

[Guillain-Barré syndrome of axonal type, Campylobacter jejuni infection and anti-ganglioside GM1 antibodies].

Infection by Campylobacter jejuni (C. jejuni) has been reported in 17 to 55 p. 100 of the GBS. The "axonal" GBS has been recently attributed to such an association. It is characterized by rapid progression to severe widespread paralysis, respiratory failure, poor and delayed recovery. The acute "axonal" form of Guillain-Barré syndrome has been and remains a matter of controversy. A typical case of GBS with serological evidence of recent C. jejuni infection and increased antibodies to GM1 is reported. An immune mechanism remains most likely. Recent studies have suggested the hypothesis of "shared epitope" between C. jejuni and peripheral nervous system cell (Gal beta 1-3 N Acetylgalactosamine epitope). Such a cross-reactivity could provoke a severe form of GBS with a poor recovery in some predisposed hosts (antiganglioside antibodies, HLA "immunogenic" groups such as B8, B35 or DR3).

Antibodies↗

PubMed1996

[Acute myopathy in an asthmatic patient treated with corticoids and muscle relaxants in the intensive care unit].

Acute myopathy occurred in a 49-year-old woman hospitalized in the intensive care unit for status asthmaticus. She was given high-dose intravenous steroid therapy and intubated. Pancuronium bromide was used for prolonged curarization. Flaccid quadriplegia developed with preservation of the deep tendon reflexes. Muscle biopsy showed a myogenic process with disorganized myofibrils and selective loss of thick myosin filaments. This mainly myogenic process would result from the toxic effect of corticosteroids favored by prolonged curarization although the effect of other factors still remains unknown.

Acute Disease↗

PubMed1996

Immunoassays fail to detect antibodies against neuronal calcium channels in amyotrophic lateral sclerosis serum.

Recent studies suggested that autoantibodies that bind to voltage-dependent calcium channels and activate calcium entry may play a role in the progressive degeneration of motoneurons in sporadic amyotrophic lateral sclerosis. Immunoassays were performed to assess autoantibody titer in patients with amyotrophic lateral sclerosis or Lambert-Eaton myasthenic syndrome, a disease in which the presence of anti-calcium channel antibodies is well documented. Based on immunoprecipitation assays for antibodies against N-type calcium channels, only 8% (2/25) of amyotrophic lateral sclerosis patients had marginally positive titers, whereas 58% (18/31) of patients with Lambert-Eaton myasthenic syndrome had positive titers. Enzyme-linked immunosorbent assays with purified neuronal N-type calcium channels revealed immunoreactivity in 2 of 25 amyotrophic lateral sclerosis sera and 12 of 31 Lambert-Eaton myasthenic syndrome sera, which is not compatible with suggestions that enzyme-linked immunosorbent assay is a more sensitive technique for the detection of autoantibodies in amyotrophic lateral sclerosis. Furthermore, based on immunoprecipitation assays, amyotrophic lateral sclerosis sera were totally negative for antibodies against L-type calcium channels from skeletal muscle or brain. These data do not support the hypothesis that an autoimmune response against calcium channels plays a primary role in amyotrophic lateral sclerosis.

Amyotrophic Lateral Sclerosis↗