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P M Gonnaud

Publications and source records attributed to P M Gonnaud.

At least 19 recordsLinked to original sources
PubMed2001

Regional differences and metabolic changes in normal aging of the human brain: proton MR spectroscopic imaging study.

BACKGROUND AND PURPOSE: Aging is recognized to originate from a diversity of mechanisms that blur the limits between normal and pathologic processes. The purpose of this study was to determine the early effect of normal aging on the regional distribution of brain metabolite concentrations, including N-acetylaspartate (NAA), a major neuronal marker, choline (Cho), and creatine (Cr). METHODS: Thirty-two healthy participants, ages 21 to 61 years, were examined by proton MR spectroscopic (1H MRS) imaging. 1H MRS imaging acquisitions were performed in two brain locations: the centrum semiovale and the temporal lobe. Thirty voxels were selected in four cerebral regions, cortical, semioval, temporal, and hippocampal, and 1H MR spectra were processed to determine the metabolite ratios. RESULTS: With advancing age of the participants, the ratios of %NAA, NAA:Cho, and NAA:Cr were significantly decreased, whereas the ratios of %Cho and %Cr were significantly increased in the cortical, semioval, and temporal regions. On the basis of the significant metabolic difference determined by cluster analysis, two groups of 16 participants with ages ranging from 21 to 39 years (younger group) and 40 to 61 years (older group) were compared. Repeated measures analysis of variance tests, with multiple comparison procedures between the two age groups and among the four brain region groups, showed significant decreases of the %NAA, NAA:Cho, and NAA:Cr ratios in the semioval and temporal regions of the older group compared with the younger group. When compared with other cerebral regions, %NAA and %Cho ratios were significantly decreased in the hippocampal and cortical regions, respectively. CONCLUSION: These metabolic changes suggest that brain aging is characterized by a reduction in neuronal viability or function associated with an accelerated membrane degradation and/or an increase in glial cell numbers.

Adult↗
PubMed2000

Exercise test in muscle channelopathies and other muscle disorders.

We studied the percentage change in compound muscle action potential (CMAP) amplitude and area during and after a 5-min maximal contraction of the muscle. The exercise test (ET) was performed on 64 patients with different muscle disorders and on 46 normal controls. The range of normal ET values was defined as the mean + 2 SD of the control values. The mean sensitivity of the test was 63% in the whole group with ion channel muscle disorders, the highest sensitivity being seen in primary periodic paralysis (81%) and the lowest in chloride channelopathies (17%). In thyrotoxic periodic paralysis, the ET was abnormal in the three of the four patients studied. In patients with myotonic dystrophy, a smaller than normal increase in CMAP amplitude occurred during and after exercise, whereas in proximal myotonic myopathy a normal initial increase in CMAP amplitude was followed by an abnormal decrement. We conclude that the ET can be of use in confirming abnormal muscle membrane excitability in patients with calcium and sodium channelopathies and thyrotoxic periodic paralysis. In chloride channelopathy, the test may also be abnormal, but shows no, or only a small, increase in amplitude or area in the immediate postexercise period. The test may also be abnormal in proximal myotonic myopathy, but is normal in myotonic dystrophy.

Action Potentials↗
PubMed1999

Painful seizures with allodynia in an 11-year-old boy.

An 11-year-old boy's epileptic seizures started with a feeling of impending crisis, dizziness, headache, and a bad taste in the mouth. This was followed by swallowing and a burning sensation in the left hand. At the same time, other parts of the body experienced allodynia. MRI and CT scans showed a right anteromesial temporal lesion which proved at neuropathology to be a ganglioglioma. Lesionectomy resulted in complete cessation of seizures. Seizures were absent at an 18-month follow-up. Allodynia is discussed in relation to the locality of the lesion.

Child↗
PubMed1998

Sympathetic skin responses and psychogenic erections in spinal cord injured men.

Sympathetic skin responses (SSR) are a simple procedure to investigate sympathetic activity. More specifically, SSR elicited from median nerve stimulation and recorded from the feet and genitals assess sympathetic activity resulting from thoracic-lumbar (TL) innervation. Since TL innervation is also involved in the mediation of psychogenic erection in spinal cord injured men, this study investigated the relationship between SSR and psychogenic erection in spinal cord injured subjects. The results support a general association between SSR and psychogenic erection and show that subjects who maintain SSR responses in the feet and genitals generally maintain psychogenic erections as well. Inconsistent cases are discussed from a theoretical and clinical perspective and overall results are discussed in terms of their clinical application in the evaluation of sexual function in spinal cord injured men.

Adolescent↗
PubMed1997

[Paraneoplastic intestinal pseudo-occlusion and sensory neuronopathy disclosing small-cell bronchial cancer].

This report describes a case of paraneoplastic neurological syndrome associating a subacute sensory neuronopathy and an intestinal pseudo-obstruction in a 64-year old man with a small cell lung cancer. Various paraneoplastic neurological syndromes have been described in association with small cell lung cancer. In our patient anti-Hu antibodies were identified by indirect immunohistochemistry and western-blot analysis. This antibody constitutes an informative tool in assessing the paraneoplastic origin of neurologic symptoms when the etiological inquiry is negative. Its positivity is important in promoting the search for an underlying malignancy and should lead to repeat investigations if the first investigations are normal.

Carcinoma, Small Cell↗
PubMed1996

Modelization of motor nerve conduction velocities for Charcot-Marie-Tooth (Type-1) patients. CMT-France Network.

Charcot-Marie-Tooth (CMT) type-1 (CMT1) neuropathy is characterized by peripheral nerve demyelination and has been divided into several subtypes. The most frequent among these, subtype 1A, is related to a microduplication of the region p11.2 of chromosome 17. This region contains the PMP-22 gene which is involved in peripheral nerve myelination. Since motor nerve conduction velocity (MNCV) is closely related to nerve myelination, we compared type-1A patient MNCVs versus non-A CMT1 patient MNCVs, in 57 CMT1A patients and 21 non-A type-1 patients. Patients with the 17p11.2 duplication have MNCVs that are significantly more reduced (about 20 m/s) compared to patients without the 17p11.2 duplication (about 30 m/s). This study also permits a model of the MNCV in the median nerve (MedMNCV) of CMT1 patients, with age, gender and molecular status as parameters. Furthermore, in order to help clinicians to diagnose subtypes of CMT1 patients, the probability for type 1A is modeled as a function of MedMNCV only.

Adolescent↗
PubMed1995

[Hereditary motor and sensory neuropathy of Charcot-Marie-Tooth disease].

Charcot-Marie-Tooth disease (Hereditary Motor and Sensory Neuropathy) sometimes begins during childhood and can lead to learning and/or orthopedic disabilities. Due to the genetic and clinical heterogeneity of the disease, the diagnosis is based on a familial study of clinical, electromyographic and pathological abnormalities. Two major types of Charcot-Marie-Tooth disease have been described. Type 1 is characterized by a decrease in nerve conduction velocities and by a peripheral nerve hypertrophy due to myelinic alterations, while type 2 is the consequence of axonal alterations. Although type 1 and type 2 patients share similar clinical symptoms, type 2 patients have normal nerve conduction velocities and histological signs of axonal damage. Several genes involved in this disease have been recently located, and, in certain cases, an individual and direct diagnosis is available if the familial abnormality is related to chromosome 17.

Adolescent↗
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

[Progressive lupus dementia. 2 cases with or without antiphospholipid antibodies].

Two cases of lupus dementia presented many points of particular interest: 1) the progressive installation of intellectual deterioration, inaugural for the first observation; 2) the diagnostic difficulties of neurolupus with the ARA criteria; 3) the appearance of cerebral magnetic resonance imaging with confluent hypersignals of the periventricular white matter on T2-weighted images; 4) the patholophysiological hypotheses: vascular disease? immunologic disease?; 5) the clinical improvement and SPECT amelioration for the second patient with corticosteroids.

Antibodies, Antiphospholipid↗
PubMed1994

Detection of deletion within 17p11.2 in 7 French families with hereditary neuropathy with liability to pressure palsies (HNPP).

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant peripheral neuropathy which is characterized by recurrent episodes of truncular palsies. We have analyzed the D17S122 locus in 7 French families, including 18 affected members, with microsatellite RM11GT and the RFLP probe VAW409R3a. Only one allele could be detected in all affected individuals with the highly polymorphic RM11GT marker. Allele segregation at D17S122 showed no contribution from the affected parent to the affected child, demonstrating that an interstitial deletion within the 17p11.2 region is associated with HNPP in the 7 families studied. This same region is duplicated, however, in another inherited neuropathy, Charcot-Marie-Tooth 1A disease. This would be the first example of two dominantly inherited diseases caused by a 'in mirror image' deletion/duplication mechanism where a gene dosage effect would be sufficient to produce two different phenotypes characterized by abnormal myelination of the peripheral nerves. The RM11GT microsatellite is an informative tool for the molecular diagnosis of HNPP.

Alleles↗
PubMed1992

[Bilateral thalamic glioma. A clinicopathological study of 2 cases].

Two cases of bilateral thalamic glioma in a 70 year-old man and a 8 year-old boy, documented by MRI and pathological data are reported. Such tumors are rare. Early symptoms may be misleading, with intellectual impairment or psychiatric disorders together with a normal CT scan. MRI and pathological findings support the view that bilateral thalamic gliomas represent a particular clinico-pathological entity among thalamic tumors.

Aged↗
PubMed1990

Ultrastructural study of the skin in a case of juvenile ceroid-lipofuscinosis.

Ceroid-lipofuscinosis (CL) is a neurometabolic disorder due to an as yet unknown enzymatic deficiency. The electron-microscopic study of various organs shows a storage of a lipofuscin-like material. The ultrastructural study of clinically uninvolved skin in a typical case of juvenile CL is reported. Granular osmiophilic deposits were found in several cell types in the dermis, including fibroblasts, endothelial cells, macrophages, Schwann cells, pericytes, and muscle cells. Neither fingerprint nor curvilinear profiles could be observed. These findings demonstrate the involvement of clinically normal skin in CL and confirm the usefulness of the EM study of the skin in the diagnosis of this rare disorder.

Adult↗
PubMed1989

[Chronic peripheral neuropathies with corticosensitive heredodegenerative aspects: 2 cases].

Two cases of peripheral neuropathy beginning in childhood are reported. Both had features suggestive of HMSN with pes cavus and kyphoscoliosis. Familial history of HMSN type I was present in 9 members of the kinship in case 1. In case 2, a mild neuropathy without pes cavus was present in the father. Case 1 developed four relapses of ascending sensory-motor deficit with conduction blocks suggestive of a superimposed chronic inflammatory polyneuropathy (CIP) which improved under prednisone. In case 2, the course was progressive with a severe proximal and distal motor weakness and sensitive disturbances. CSF protein concentration was high. Nerve biopsy showed rare onion bulbs and intense demyelination. These results joint to the unspecificity of the father's neuropathy are consistent with a probable childhood. CIP which improved under prednisone. These two cases indicated that in some patients with unusual symptoms for HMSN, prednisone should be considered and that the physiopathology of these neuropathies is probably heterogeneous.

Child↗