PubMed Health⌕ Search

Biomedical subjects

M Raynaud

Publications and source records attributed to M Raynaud.

At least 19 recordsLinked to original sources
PubMed2006

[Non traumatic high flow priapism: arterial embolization treatment].

PURPOSE: To report cases of non traumatic high flow priapism treated by arterial embolization. MATERIAL AND METHODS: Six men presented with non traumatic high flow priapism, the diagnosis was based on colour Doppler ultrasound, cavernous blood gas analysis with arterial blood saturation levels and failed medical or surgical therapy. Four patients had sickle cell disease. The embolization was performed with Gelfoam and was unilateral in one case, bilateral in the other cases. RESULTS: Detumescence occurred in a few hours in all cases. One patient had recurrent priapism two years after and was treated by embolization. Transient erectile dysfunction was observed in five cases, permanent in one case. CONCLUSION: Arterial embolization is the treatment of choice in high flow priapism with low rate of permanent erectile dysfunction.

Adolescent↗
PubMed2005

Screening of ARX in mental retardation families: Consequences for the strategy of molecular diagnosis.

Mutations in the human ARX gene have been shown to cause nonsyndromic X-linked mental retardation (MRX) as well as syndromic forms such as X-linked lissencephaly with abnormal genitalia (XLAG), Partington syndrome and X-linked infantile spasm. The most common causative mutation, a duplication of 24 bp, was found in families with a variety of phenotypes, but not in the more severe XLAG phenotypes. The aim of the study was to access the frequency of ARX mutations in families with established or putative X-linked mental retardation (XLMR) collected by the European XLMR Consortium. We screened the entire coding region of ARX for mutations in 197 novel XLMR families by denaturing high-performance liquid chromatography, and we identified eight mutations (six c.428_451dup24, one insertion and one novel missense mutation p.P38S). To better define the prevalence of ARX mutations, we included previously reported results of 157 XLMR families. Together, these data showed the relatively high rate (9.5%) of ARX mutations in X-linked MR families and an expectedly low rate in families with affected brother pairs (2.2%). This study confirms that the frequency of ARX mutations is high in XLMR, and the analysis of ARX in MRX should not be limited to duplication.

Amino Acid Sequence↗
PubMed2005

Anomalous multiphoton photoelectric effect in ultrashort time scales.

In a multiphoton photoelectric process, an electron needs to absorb a given number of photons to escape the surface of a metal. It is shown for the first time that this number is not a constant depending only on the characteristics of the metal and light, but varies with the interaction duration in ultrashort time scales. The phenomenon occurs when electromagnetic energy is transferred, via ultrafast excitation of electron collective modes, to conduction electrons in a duration less than the electron energy damping time. It manifests itself through a dramatic increase of electron production.

Journal Article↗
PubMed2003

A third MRX family (MRX68) is the result of mutation in the long chain fatty acid-CoA ligase 4 (FACL4) gene: proposal of a rapid enzymatic assay for screening mentally retarded patients.

BACKGROUND: The gene encoding fatty acid CoA ligase 4 (FACL4) is mutated in families with non-specific X linked mental retardation (MRX) and is responsible for cognitive impairment in the contiguous gene syndrome ATS-MR (Alport syndrome and mental retardation), mapped to Xq22.3. This finding makes this gene a good candidate for other mental retardation disorders mapping in this region. METHODS: We have screened the FACL4 gene in eight families, two MRX and six syndromic X linked mental retardation (MRXS), mapping in a large interval encompassing Xq22.3. RESULTS: We have found a missense mutation in MRX68. The mutation (c.1001C>T in the brain isoform) cosegregates with the disease and changes a highly conserved proline into a leucine (p.P375L) in the first luciferase domain, which markedly reduces the enzymatic activity. Furthermore, all heterozygous females showed completely skewed X inactivation in blood leucocytes, as happens in all reported females with other FACL4 point mutations or deletions. CONCLUSIONS: Since the FACL4 gene is highly expressed in brain, where it encodes a brain specific isoform, and is located in hippocampal and cerebellar neurones, a role for this gene in cognitive processes can be expected. Here we report the third MRX family with a FACL4 mutation and describe the development of a rapid enzymatic assay on peripheral blood that we propose as a sensitive, robust, and efficient diagnostic tool in mentally retarded males.

Adolescent↗
PubMed2001

Ponderomotive acceleration of photoelectrons in surface-plasmon-assisted multiphoton photoelectric emission.

Photoelectrons emitted from a gold target via a surface-plasmon-assisted multiphoton photoelectric process under a femtosecond laser pulse of moderate intensity are much more energetic than in an ordinary photoeffect without electron collective excitation. The phenomenon is interpreted in terms of time-dependent ponderomotive acceleration of the particles by the resonant field localized at the metal surface. The amplitude of the plasmon resonance may be directly estimated by means of the electron energy spectra.

Journal Article↗
PubMed2000

Systematic analysis of X-inactivation in 19XLMR families: extremely skewed profiles in carriers in three families.

It has been demonstrated in several X-linked disorders, both with and without mental retardation, that the X-inactivation process plays a significant role in the expression of X-linked diseases in females. Moreover, in some disorders extremely skewed inactivation of the X chromosome is constant in carriers, and this is thought to result from a proliferation or a survival advantage for cells expressing the normal allele at this locus over cells expressing the mutated allele. X-linked mental retardation (XLMR) is heterogeneous, and cloning and characterization of the mutated genes are in progress. XLMR can be expressed in carrier females but often with milder manifestations. We report the systematic study of the X-inactivation profile of obligate carriers and other females in 19 multiplex XLMR pedigrees, using leucocyte-extracted DNA. Extremely skewed profiles were observed in carriers in three of 19 families.

Dosage Compensation, Genetic↗
PubMed2000

Severe cognitive impairment in DMD: obvious clinical indication for Dp71 isoform point mutation screening.

Duchenne muscular dystrophy is associated with variable degrees of selective cognitive defect with lower scores for verbal intelligence and reading abilities. A number of findings have shown that rearrangements located in the second part of the gene seem to be preferentially associated with cognitive impairment. Several dystrophin transcripts are expressed in the brain. The more distal of them, Dp71, is predominant. We have carried out a mutational analysis of Dp71 transcript in 12 DMD patients severely, mildly or not retarded, all without detectable deletion or duplication. We have detected five point mutations causing Dp71 premature translation termination. All were found among the more severely mentally retarded patients of this group (VIQ < 50 and/or no reading acquisition).

Adolescent↗
PubMed1999

Significance of late ventricular potentials in myotonic dystrophy.

In 39 patients with myotonic dystrophy, we found a high percentage of infrahissian cardiac conduction abnormalities (51%) and late potentials (46%), whereas spontaneous and inducible ventricular arrhythmias were rare. These results suggest that the prolongation of QRSD and the duration of the low-amplitude signal on the signal-averaged electrocardiogram were related to delayed activation of the His and Purkinje tissue rather than true late potentials.

Adult↗
PubMed1999

X-linked nonspecific mental retardation (MRX16) mapping to distal Xq28: linkage study and neuropsychological data in a large family.

A genetic linkage study was performed on a large four-generation family with variable nonspecific X-linked mental retardation (MRX16), speech abnormalities, and retardation of all milestones. Significant linkage was found in the Xq28 region with loci DXS52, DXS15, BGN, and DXS1108 with maximum LOD scores of 4.86, 4.01, 4.83, and 5.43, respectively, at theta = 0.00. Recombination was observed at the locus DXS1113, thus mapping the gene in an 8-Mb interval between this marker and the Xq telomere. Linkage intervals of three other MRX families overlap with this interval in Xq28 where the RABGDIA gene, mutated in the MRX41 and MRX48 families, is also located. In MRX3, MRX28, but also in MRX16, no alteration of RABGDIA has been found, thus suggesting the existence of at least two MRX genes in distal Xq28.

Chromosome Mapping↗
PubMed1999

Evidence for a new X-linked mental retardation gene in Xp21-Xp22: clinical and molecular data in one family.

Linkage analysis was performed in three generations of a French family segregating a syndromal form of X-linked mental retardation. All affected males had neonatal hypotonia, seizures, muscular hypodevelopment, and severe mental deficiency. A peak lod score of 2.90 at a recombination fraction of theta = 0 was detected for DXS 1052 and DXS 451 (Xp22.13). Recombination between the disease locus and the polymorphic markers in DXS7163 and DXS1238 suggested a gene mapping to the Xp22.13-Xp21.2 region. Three candidate genes in this region were investigated: the cDNA for kinase Rsk-2 involved in Coffin-Lowry syndrome, the brain-specific exon of a transcript in the DMD locus (DP140 isoform of dystrophin), and exon 18 of the glycerol kinase gene, which is specific to fetal brain transcripts. All three sequences were normal.

Adult↗
PubMed1999

Is it possible to identify infrahissian cardiac conduction abnormalities in myotonic dystrophy by non-invasive methods?

OBJECTIVE: To identify intracardiac conduction abnormalities in patients with myotonic dystrophy from their clinical, ECG, and genetic features. METHODS: 39 consecutive patients (mean (SD) age 42. 9 (12.1) years; 16 female, 23 male) underwent clinical examination, genetic studies, resting and 24 hour ambulatory ECG, signal averaged ECG, and electrophysiological studies. RESULTS: 23 patients suffered from cardiac symptoms, 23 had one or more cardiac conduction abnormality on resting ECG, one had sinus deficiency, and 21 (53.8%) had prolonged HV intervals. No correlation was found between the severity of the neurological symptoms, onset of disease, cardiac conduction abnormalities on ECG, and the intracardiac conduction abnormalities on electrophysiological study. The size of the DNA mutation was longer in the abnormal HV interval group than in the normal HV interval group (3.5 (1.8) v 2.2 (1.0) kb, p < 0.02). Signal averaged ECG parameters (total QRS duration (QRSD) and duration of low amplitude signals </= 40 microV (LAS 40)) were greater in patients with an abnormal HV interval than in those with a normal HV interval (123.4 (24.6) v 102.8 (12.3) ms and 47.5 (12.8) v 35.3 (8.8) ms, respectively; p < 0.005). Only the association of QRSD >/= 100 ms with LAS 40 >/= 36 ms identified patients with an abnormal HV interval with good sensitivity (80%) and specificity (83. 3%). CONCLUSIONS: Infrahissian conduction abnormalities are common in myotonic dystrophy and can be identified using signal averaged electrocardiography.

Adult↗
PubMed1998

Ossification of the ligamenta flava with severe myelopathy in a black patient. A case report.

STUDY DESIGN: A case of symptomatic ossification of ligamenta flava in a black man from Martinique (French West Indies) is reported. OBJECTIVES: To show that ossification of ligamenta flava may be observed in racial groups other than Japanese people and that the postoperative prognosis of symptomatic ossification of ligamenta flava is not always excellent. SUMMARY OF BACKGROUND DATA: Ossification of ligamenta flava causing slowly progressive myelopathy or radiculopathy is rare. It usually occurs in the lower thoracic spine. Ossification of ligamenta flava has mainly been described as occurring in Japanese people and very rarely in Caucasians. Diagnosis is based on a computed tomographic scan or magnetic resonance imaging, and postoperative prognosis is usually good. METHODS: Low thoracic ossification of ligamenta flava was diagnosed in a black man from Martinique, based on the computed tomographic scan data and on the histopathologic examination of the removed tissue. The patient was clinically evaluated before and 1 year after the operation. A postoperative computed tomographic scan was performed. A magnetic resonance image was not available in this case. RESULTS: The patient exhibited severe subacute myelopathy. After decompression, the neurologic recovery was incomplete. A postoperative computed tomographic scan showed complete excision of ossification of ligamenta flava and decompression of the spinal cord. CONCLUSIONS: Ossification of ligamenta flava may occur in black people. An incomplete postoperative recovery may be observed in such cases of unusual subacute compressive myelopathy.

Aged↗
PubMed1998

X-linked mental retardation with isolated growth hormone deficiency is mapped to Xq22-Xq27.2 in one family.

X-linked mental retardation (XLMR) includes distinct entities in which mental deficiency is either associated with specific abnormalities (syndromal) or not (nonsyndromal). We report on the clinical, neuropsychological, and laboratory findings and linkage analysis in one family with XLMR and isolated growth hormone deficiency (IGHD). Mental retardation was associated in 3 males and 5 females with short stature, microcephaly, and particular facial traits, i.e., high curved forehead, midface hypoplasia, and concave nasal bridge with nasal end of normal size and broad traits. Significant lod scores (Zmax >2) at a recombination fraction of theta = 0 were detected for 6 marker loci between DXS178 (Xq22.1) and DXS292 (Xq27.2). This mapping region overlaps that of XLMR with IGHD, recently reported by Hamel et al. [1996: Am J Med Genet 64:35-41] (Xq24-q27.3), and that of agammaglobulinemia with IGHD (Xq21.33-q22.2). This observation may confirm the suspicion of a gene involved in growth hormone regulation being localized in Xq.

Adult↗
PubMed1998

Isolated medial orbital blow-out fracture with medial rectus entrapment.

PURPOSE: The authors report on three cases of isolated medial orbital blow-out fracture with medial rectus entrapment which occurred in black males. Only a few similar cases have been reported in the literature. METHODS: The diagnosis was established with the help of tomography and CT scan of the orbit. RESULTS: The diagnosis could be expected from the clinical signs occurring after blow-out trauma mechanisms: eyelid emphysema, nasal subconjunctival haemorrhage, motility disturbance, enophthalmos. CONCLUSION: An ethnic anatomic hypothesis could explain the predominance of this fracture in blacks. This fracture often remains undiagnosed. The diagnosis was based on axial and especially coronal CT scan of the orbit. The physician should be alerted by some clinical signs that justify these radiographic techniques.

Adult↗
PubMed1997

[Extensive cerebral venous thrombosis resistant to heparin: local fibrinolysis with urokinase].

A 37 year-old man had headaches for 10 days, then a single tonic-clonic seizure and coma due to an extensive cerebral venous thrombosis. In spite of full-dose heparin treatment for 7 days, the clinical picture worsened along with increasing edema on CT-Scan. Direct thrombolytic treatment was then performed using transvenous catheterization and instillation of Urokinase (2.6 MU over 4 days). A near complete repermeabilization of the sinuses was obtained and the patient improved dramatically in a few days. The only adverse effect of Urokinase was hematuria. Based on our experience and review of the literature which includes 26 previous cases, direct thrombolytic therapy appears to be a relatively safe procedure. This treatment should be considered in a patient with extensive dural sinus thrombosis which fails to respond to heparin treatment.

Adult↗
PubMed1996

X chromosome and infantile autism.

Family studies and epidemiologic data in autism show the involvement of genetic factors in the etiology of this syndrome. The frequent association of X chromosome with mental retardation and behavior disturbances raises the question of its implication in the etiology of autism. Several markers of X chromosome were tested in autistic and control populations by association study. The autistic population was submitted to an extensive clinical examination. For the DXS287 marker, chi 2 analysis showed a different allele distribution between control and patient groups. This difference was enhanced when children with the most severe autistic behaviors and the least serious cognitive disorders were selected for statistical comparison. To our knowledge, this is the first association study described using markers of X chromosome in infantile autism. These preliminary results encourage our research on this chromosome, which could be considered as a significant genetic component of the multifactorial etiology of autism.

Adolescent↗
PubMed1996

X-linked mental retardation with neonatal hypotonia in a French family (MRX15): gene assignment to Xp11.22-Xp21.1.

Linkage analysis was performed in a family with non-specific X-linked mental retardation (MRX 15). Hypotonia in infancy was the most remarkable physical manifestation. The severity of mental deficiency was variable among the patients, but all of them had poor or absent speech. Significant lod scores at a recombination fraction of zero were detected with the marker loci DXS1126, DXS255, and DXS573 (Zmax = 2.01) and recombination was observed with the two flanking loci DXS164 (Xp21.1) and DXS988 (Xp11.22), identifying a 17 cM interval. This result suggests a new gene localization in the proximal Xp region. In numerous families with non-specific X-linked mental retardation (MRX), the corresponding gene has been localized to the paracentromeric region in which a low recombination rate impairs the precision of mapping.

Adult↗