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R Gouider

Publications and source records attributed to R Gouider.

At least 19 recordsLinked to original sources
PubMed2006

A recommended treatment algorithm in relapsing multiple sclerosis: report of an international consensus meeting.

An International Working Group for Treatment Optimization in MS met to recommend evidence-based therapeutic options for the management of suboptimal responses or intolerable side-effects in patients treated with disease-modifying drugs (DMDs) for multiple sclerosis (MS). Several DMDs are now available for the treatment of MS that have been shown to alter the clinical course of the disease by decreasing disease activity and delaying the progression of disability. Nevertheless, many patients continue to experience disease activity whilst on treatment, and recommendations have been made on how the success of therapy in an individual patient can be assessed. However, even after having identified criteria for a suboptimal response to current treatments, clinicians require guidance on how to improve the outcomes. This report summarizes the conclusions from a workshop at which this issue was addressed. We suggest treatment pathways for optimizing therapy for those patients with suboptimal responses to DMDs, and therapeutic options for patients with unacceptable side-effects on their current therapy.

Algorithms↗
PubMed2006

Autosomal-recessive forms of demyelinating Charcot-Marie-Tooth disease.

Autosomal-recessive forms of Charcot-Marie-Tooth (ARCMT) account for less than 10% of the families in the European CMT population but are more frequent in the Mediterranean basin and the Middle East because of more widespread consanguinity. Until now, demyelinating ARCMT was more extensively studied at the genetic level than the axonal form. Since 1999, the number of localized or identified genes responsible for demyelinating ARCMT has greatly increased. Eight genes, EGR2, GDAP1, KIAA1985, MTMR2, MTMR13, NDRG1, PRX, and CTDP1, have been identified and two new loci mapped to chromosomes 10q23 and 12p11-q13. In this review, we will focus on the particular clinical and/or neuropathological features of the phenotype caused by mutations in each of these genes, which might guide molecular diagnosis.

Cataract↗
PubMed2003

Mutations in MTMR13, a new pseudophosphatase homologue of MTMR2 and Sbf1, in two families with an autosomal recessive demyelinating form of Charcot-Marie-Tooth disease associated with early-onset glaucoma.

Charcot-Marie-Tooth disease (CMT) with autosomal recessive (AR) inheritance is a heterogeneous group of inherited motor and sensory neuropathies. In some families from Japan and Brazil, a demyelinating CMT, mainly characterized by the presence of myelin outfoldings on nerve biopsies, cosegregated as an autosomal recessive trait with early-onset glaucoma. We identified two such large consanguineous families from Tunisia and Morocco with ages at onset ranging from 2 to 15 years. We mapped this syndrome to chromosome 11p15, in a 4.6-cM region overlapping the locus for an isolated demyelinating ARCMT (CMT4B2). In these two families, we identified two different nonsense mutations in the myotubularin-related 13 gene, MTMR13. The MTMR protein family includes proteins with a phosphoinositide phosphatase activity, as well as proteins in which key catalytic residues are missing and that are thus called "pseudophosphatases." MTM1, the first identified member of this family, and MTMR2 are responsible for X-linked myotubular myopathy and Charcot-Marie-Tooth disease type 4B1, an isolated peripheral neuropathy with myelin outfoldings, respectively. Both encode active phosphatases. It is striking to note that mutations in MTMR13 also cause peripheral neuropathy with myelin outfoldings, although it belongs to a pseudophosphatase subgroup, since its closest homologue is MTMR5/Sbf1. This is the first human disease caused by mutation in a pseudophosphatase, emphasizing the important function of these putatively inactive enzymes. MTMR13 may be important for the development of both the peripheral nerves and the trabeculum meshwork, which permits the outflow of the aqueous humor. Both of these tissues have the same embryonic origin.

Adolescent↗
PubMed2003

[Cerebral tuberculomas].

We report eight cases of brain tuberculoma. The clinical presentation was polymorphous: partial epilepsy (n=4), headache (n=3), hemiplegia (n=1), meningitis (n=1), cerebellar syndrome (n=1). Six patients also had pulmonary tuberculosis, one had tuberculosis of the genital organs, and one had HIV co-infection. The brain CT scan and MRI were highly contributive to diagnosis and follow-up. Despite good compliance with an anti-tuberculosis regimen for at least 14 months, the course was favorable in only six patients. Adjunction of corticosteroids led to radiological improvement. Assessment of cell immunity demonstrated a diminished immunomodulator ratio. Cerebral tuberculoma should be searched for in patients with unexplained neurological manifestations and several intracerebral lesions, particularly if pulmonary or visceral tuberculosis and/or immunodepression is part of the clinical picture.

Adrenal Cortex Hormones↗
PubMed2001

The frequency of 17p11.2 duplication and Connexin 32 mutations in 282 Charcot-Marie-Tooth families in relation to the mode of inheritance and motor nerve conduction velocity.

The 17p11.2 duplication and Connexin 32 (Cx32) mutations are the most frequent gene mutations responsible for Charcot-Marie-Tooth diseases. We classified 282 Charcot-Marie-Tooth families according to the median motor nerve conduction velocity of the index patient and the mode of inheritance, and screened them for 17p11.2 duplication and Cx32 mutations. Forty-seven percent of the Charcot-Marie-Tooth families had median motor nerve conduction velocity under 30 m/s (group 1), 15% between 30 and 40 m/s (group 2), and 28% over 40 m/s (group 3). Spinal Charcot-Marie-Tooth (group 4) was observed in 7% of the families. Modes of inheritance were not similarly represented among the different groups. The 17p11.2 duplication was detected in index patients of group 1 only, and accounted for 83% of the familial cases and 36% of the isolated cases. In contrast, 21 Cx32 mutations were detected to variable degrees in groups 1-3, but were most numerous by far in dominant families of group 2 (44%). This systematic approach was taken to estimate the frequency of 17p11.2 duplication and Cx32 mutations in the different Charcot-Marie-Tooth subgroups, in order to propose a practical strategy for molecular analysis.

Adult↗
PubMed2001

Clinical, electrophysiological and molecular genetic characteristics of 93 patients with X-linked Charcot-Marie-Tooth disease.

X-linked dominant Charcot-Marie-Tooth (CMTX) disease is a motor and sensory neuropathy caused by mutations in the connexin 32 (CX32) gene. In this study we report the clinical, electrophysiological and genetic features of 93 patients (41 males, 52 females) from 37 unrelated families with CMTX. Age at onset was 15.4 +/- 9.6 years in males (range 1-40 years) and 18.7 +/- 13.1 years in females (range 1-56 years) (P = 0.22) and the duration of disease at the time of examination was 18.3 +/- 14.6 years in males and 23.9 +/- 13.7 years in females (P = 0.11). Males were more severely affected than females, with significantly more frequent muscle weakness, amyotrophy, proprioception loss, upper limb areflexia and pes cavus. Females were more frequently asymptomatic, whereas high functional disability scores were more frequently encountered in males. The electrophysiological studies showed that motor nerve conduction velocities in CMTX females, but not males, were heterogeneous between nerves compared with Charcot-Marie-Tooth type 1A (CMT1A) patients and controls. The terminal latency index (TLI) for the median nerve was 0.37 +/- 0.08; it was similar in men and in women and a little higher than those observed in CMT1A and controls. The range of values for median TLI was wider in both male and female CMTX patients than in controls, but was similar to that of CMT1A patients, suggesting that motor conduction was relatively homogeneous within a given nerve. Twenty-seven different CX32 mutations, including missense (n = 23), nonsense (n = 2) and frameshift mutations (n = 1) and one entire deletion of the CX32 coding sequence, were observed in the 37 families. Four of these mutations are described for the first time. The phenotype of the patients, especially age at onset, is discussed in relation to the functional consequences of CX32 mutations, analysed in vitro in Xenopus oocytes and mammalian cells. CMTX patients with age at onset in the first decade mostly presented non-functional mutations, suggesting that the physiological consequences of the mutations affect age at onset in CMTX.

Adolescent↗
PubMed1999

Spectrum of clinical and electrophysiologic features in HNPP patients with the 17p11.2 deletion.

OBJECTIVE: To study the clinical and electrophysiologic features of a large series of carriers of the 17p11.2 deletion. BACKGROUND: The 17p11.2 deletion is associated in most patients with recurrent acute nerve palsies, which is the typical presentation of hereditary neuropathy with liability to pressure palsies (HNPP). Nevertheless, a few other phenotypes have been reported. METHODS: On the basis of clinical and electrophysiologic data, the authors conducted a retrospective study of 99 individuals with the 17p11.2 deletion referred to their neurogenetic department between 1993 and 1997. RESULTS: In addition to the typical presentation of HNPP, they describe five other phenotypes in 15 patients: recurrent positional short-term sensory symptoms, progressive mononeuropathy, Charcot-Marie-Tooth disease-like polyneuropathy, chronic sensory polyneuropathy, and chronic inflammatory demyelinating polyneuropathy-like, recurrent subacute polyneuropathy; and 14 asymptomatic patients. In all the deletion carriers, regardless of their phenotype and by the second decade, the authors found a characteristic, multifocal electrophysiologic neuropathy consisting of a diffuse increase in distal motor latencies contrasting with normal or moderately reduced motor nerve conduction velocities, a diffuse reduction in sensory nerve action potential, and multiple focal slowing of nerve conduction at the usual sites of entrapment. The key diagnostic criterion is a bilateral slowing of sensory and motor nerve conduction at the carpal tunnel with at least one abnormal parameter for motor conduction in one peroneal nerve. CONCLUSION: The authors confirm the clinical phenotypic heterogeneity of the 17p11.2 deletion and suggest that electrophysiologic examination is a reliable tool for screening suspected HNPP patients in its various clinical presentations.

Adolescent↗
PubMed1999

[Neurological manifestations indicative of brucellosis].

Eight patients presented neurological signs secondary to Brucella infection. The clinical presentation was a meningoencephalitis in three cases, a meningoencephalomyelitis in one case, an epiduritis with spinal cord compression in one case, an acute polyradiculoneuritis in two cases and a chronic polyradiculoneuritis in one case. Acoustic nerve was impaired in seven cases. Cerebrospinal fluid (CSF) analysis revealed a lymphocytic meningitis and a high protein concentration in all cases. The agglutination test titers were elevated in the serum and in the CSF of seven patients (> or = 1/80) and two patients respectively. Brucella melitensis culture was disclosed in the blood of one patient and in the CSF of two patients. Three patients were treated by the association cycline and rifampicin whereas a tritherapy including cycline, rifampicin and TMP-SMZ was used in the other cases. Outcome was favorable in seven cases. This study outlines the polymorphism of neurological manifestations due to brucellosis, even in familial cases and this diagnostic must be especially done in Middle East and South Mediterranean countries.

Acute Disease↗
PubMed1999

[Polyneuropathy due to glue-sniffing intoxication. Report of a case].

We report a case of a 24 years old female who presented a glue sniffing neuropathy. Symptoms began with progressive weakness which initially involves the lower extremities. Neurological examination noted a decreased Achille reflexes. Nerve conduction studies showed a slowing nerve conduction velocities, a delayed F waves and distal latencies and diffuse nerve conduction blocks. The disease continued to worsen beyond two weeks after stopping intoxication with persistent evidence of ongoing demyelination. 40 days later we have noted an improvement in nerve conduction velocities and in conduction blocks, neuropathy is the most frequent glue sniffing complications, there is a clinic and electric improvement of the polyneuropathy after stopping intoxication.

Adult↗
PubMed1998

A PCR amplification method reveals instability of the dodecamer repeat in progressive myoclonus epilepsy (EPM1) and no correlation between the size of the repeat and age at onset.

Progressive myoclonus epilepsy of the Unverricht-Lundborg type (EPM1) is a rare, autosomal recessive disorder characterized by onset at age 6-16 years, generalized seizures, incapacitating myoclonus, and variable progression to cerebellar ataxia. The gene that causes EPM1, cystatin B, encodes a cysteine proteinase inhibitor. Only a minority of EPM1 patients carry a point mutation within the transcription unit. The majority of EPM1 alleles contain large expansions of a dodecamer repeat, CCC CGC CCC GCG, located upstream of the 5' transcription start site of the cystatin B gene; normal alleles contain two or three copies of this repeat. All EPM1 alleles with an expansion were resistant to standard PCR amplification. To precisely determine the size of the repeat in affected individuals, we developed a detection protocol involving PCR amplification and subsequent hybridization with an oligonucleotide containing the repeat. The largest detected expansion was approximately 75 copies; the smallest was approximately 30 copies. We identified affected siblings with repeat expansions, of different sizes, on the same haplotype, which confirms the repeat's instability during transmissions. Expansions were observed directly; contractions were deduced by comparison of allele sizes within a family. In a sample of 28 patients, we found no correlation between age at onset of EPM1 and the size of the expanded dodecamer. This suggests that once the dodecamer repeat expands beyond a critical threshold, cystatin B expression is reduced in certain cells, with pathological consequences.

Adolescent↗
PubMed1998

X-linked Charcot-Marie-Tooth disease with connexin 32 mutations: clinical and electrophysiologic study.

OBJECTIVE: To relate X-linked Charcot-Marie-Tooth disease (CMTX) phenotypes to gender and type of neuropathy by the study of a large series of CMTX patients with proven Cx32 point mutations. BACKGROUND: CMTX is an X-linked form of Charcot-Marie-Tooth disease, caused by mutations in the connexin 32 gene. Males are usually more severely affected and have slower nerve conduction velocities than females. METHODS: Forty-eight patients from 10 families with Cx32 mutations were examined clinically and electrophysiologically. Mutations were characterized in index cases by automatic sequencing and detected in at-risk individuals by polymerase chain reaction (PCR)-restriction or single strand conformation polymorphism (SSCP) analysis. Two patients from different families had light and electron microscopy examination of a sural nerve biopsy. RESULTS: Males (n = 21) were more severely affected than females (n = 27), although six of the females were severely disabled. In the majority of males, the median motor nerve conduction velocity (MNCV) was between 30 and 40 m/s, whereas in females it ranged from 30 to normal values. Two children with mutation, a 6-year-old boy and a 7-year-old girl, were normal clinically and electrophysiologically. In most patients, the amplitude of motor nerve compound muscle action potentials (CMAP) was reduced in all nerves tested. MNCV was reduced as a function of the degree of axonal loss. A significant correlation was found between the decrease in CMAP amplitude and MNCV in the median, ulnar, and peroneal nerves. Sural nerve biopsies in one patient with a missense and one with a nonsense mutation both showed axonal neuropathy. CONCLUSION: Electrophysiologic and histologic findings support primary axonal neuropathy in CMTX with Cx32 mutations. Clinical and electrophysiologic data in males with different missense mutations in the of Cx32 gene differed significantly. Furthermore, males with a nonsense mutation (Arg22Stop) had earlier onset and a more severe phenotype than males with missense mutations.

Adolescent↗
PubMed1998

[Unverricht-Lündborg disease: clinical and electrophysiologic study of 19 Maghreb families].

We describe clinical, electrophysiological and genetic features in 44 patients with Unverricht-Lündborg disease from 19 families living in North African countries (Tunisia, Algeria and Morocco). The mean age of patients was 25.3 years; mean age was at onset 11.3 years. The disease began more frequently with seizures (91 per cent) or myoclonus (80 p. 100) than ataxia (16 p. 100). Subsequently myoclonus and generalized seizures were present in all patients, cerebellar signs were absent in four cases. EEG findings included normal background activity (90 p. 100), spontaneous fast generalized spikes (93 p. 100) and photosensitivity (70 p. 100). Antiepileptic polytherapy (clonazepam and/or phenobarbital and/or valporic acid) was used in 84 per cent of cases. Antiepileptic drugs were more effective in controlling epileptic seizures (less than one seizure/month in 60 p. 100) than myocloni which persisted daily in 64 p. 100 of cases. Mean duration of the disease was 13.5 years. One patient died of status epilepticus. Consanguinity was noted in 17 families (first degree in 15 families). Linkage to chromosome 21q 22.3 was confirmed in 11 families. We noted an inter and intrafamilial variability of clinical signs and disease course.

Adolescent↗
PubMed1997

Charcot-Marie-Tooth disease with intermediate motor nerve conduction velocities: characterization of 14 Cx32 mutations in 35 families.

Charcot-Marie-Tooth disease can be inherited either autosomal dominantly or recessively or linked to the X chromosome. X-linked dominant Charcot-Marie-Tooth disease (CMTX) is a sensorimotor peripheral neuropathy in which males have usually more severe clinical symptoms and decreased nerve conduction velocities than do females. CMTX is usually associated with mutations in exon 2 of the connexin 32 (Cx32) gene. DNA from 35 unrelated CMT patients, without the 17p11.2 duplication, but with median nerve conduction between 30 and 40 m/s, were tested for the presence of Cx32 mutations. The entire coding sequence of the Cx32 gene was explored using a rapid nonradioactive technique to detect single-strand conformation polymorphisms (SSCP) on large PCR fragments. Thirteen abnormal SSCP profiles were detected and characterized by sequencing. In addition, systematic sequencing of the entire Cx32 coding region in the remaining index cases revealed another mutation that was not detected by SSCP. A total of 14 mutations were found, five of which were not previously reported. These results demonstrate the high frequency (40%) of mutations in the coding region of the Cx32 gene in CMT patients with intermediate MNCV, without 17p11.2 duplications. Most of these mutations (93%) can be detected by SSCP.

Amino Acid Sequence↗
PubMed1997

Patients homozygous for the 17p11.2 duplication in Charcot-Marie-Tooth type 1A disease.

Charcot-Marie-Tooth type 1A disease is an inherited sensorimotor neuropathy that is most often associated with a duplication of chromosome 17p11.2. This region contains the gene of the peripheral myelin protein 22 (PMP22), which is responsible by a gene dosage effect for the Charcot-Marie-Tooth type 1A phenotype with 17p11.2 duplication. We performed a clinical, electrophysiological, and genetic study of a consanguinous Charcot-Marie-Tooth type 1A family with 4 affected siblings, 3 of whom were homozygous for the 17p11.2 duplication, the other a heterozygote. Comparison of phenotypes showed that the severity of the disease was variable among the homozygotes, one of whom was no more severely affected than the heterozygous sibling who was paucisymptomatic. These results suggest that the severity of the disease is not determined solely by the number of copies of the PMP22 gene.

Adult↗