Biomedical subjects

P Rondot

Publications and source records attributed to P Rondot.

At least 19 recordsLinked to original sources

PubMed1995

A new mutation in the HEXA gene associated with a spinal muscular atrophy phenotype.

We describe two adult siblings who had had mild GM2 gangliosidosis since childhood. They presented with spinal muscular atrophy and dysarthria, and one sibling also had mental disturbances. Laboratory studies established the diagnosis of the B1 variant of GM2 gangliosidosis, because the hexosaminidase (Hex) A deficiency was not present upon testing with the unsulfated synthetic substrate 4-methylumbelliferyl N-acetylglucosaminide. HEXA gene analysis proved that the patients are compound heterozygotes for the previously identified G533-->A mutation and for a new mutation, G1171-->A, at exon 11. This new mutation affects a conserved amino acid and results in a Val-->Met substitution at position 391 of the HEXA gene. Full sequence of the alpha-subunit cDNA of Hex A revealed no other mutation. Assays for Hex A activities in patients suspected of having GM2 gangliosidosis should be performed with the sulfated substrate 4-methylumbelliferyl N-acetylglucosamine 6-sulfate.

Adult↗

PubMed1992

Activity and acceptability of piribedil in Parkinson's disease: a multicentre study.

Several controlled trials have shown that the dopamine agonist, Trivastal (piribedil), is active in the treatment of Parkinson's disease, particularly with regard to tremor. To determine its efficacy as monotherapy in patients previously untreated with levodopa, a 3-month multicentre study was conducted with Trivastal 50 mg LP in 113 patients with idiopathic Parkinson's disease. The study population consisted of 66 men and 47 women, aged 63.1, SD 0.6 (43-79) years with a 2.1, SD 0.2 (1-15) year history of Parkinson's disease. Mean disease stage was 1.82 (1-4) by the Hoehn and Yahr classification. Tremor was the predominant clinical feature in 42 patients; the remaining 71 patients displayed the full parkinsonian syndrom. Trivastal 50 mg LP was prescribed stepwise up to doses of 150-250 (207, SD 6.4) mg/day at the end of 3 months. No concomitant anti-parkinsonian medication was given. Patients were clinically assessed at 1, 2 and 3 months on the Webster scale, a specific tremor scale and the HARD depression scale. Mean results were as follows in the 90 patients completing the study. On the Webster scale, tremor fell from 1.7 to 1 (-41%, P less than 0.001), bradykinesia from 1.5 to 0.8 (-47%, P less than 0.001) and rigidity from 1.3 to 0.9 (-31%, P less than 0.001); on the specific scale, rest tremor decreased in daily duration and amplitude from 3.9 to 2.4 (-39%, P less than 0.001) and from 2.9 to 2.1 (-35%, P less than 0.001), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Postural disturbances due to homonymous hemianopic visual ataxia.

Patients with visual defects often complain of disturbances of equilibrium. In order to measure the influence of visual stimulation on posture, a study was made comparing the posture of hemianopic patients with that of healthy volunteers before and after occlusion of half of the monocular visual field. Hemianopia increases lateral oscillations in patients in the standing position and the projection of the body's centre of gravity shifts towards the hemianopia: in the volunteers, the same shift is noted after masking half the visual field. A tonic effect of visual information is discussed.

Adult↗

PubMed1992

Chronic administration of L-dopa affects the movement-related cortical potentials of patients with Parkinson's disease.

The chronic effect of L-Dopa administration on the movement-related cortical potentials (MRCPs) was studied in two groups of patients with Parkinson's disease (PD): patients de novo (DN) and patients with on-off fluctuations. The BP and NS' premovement components of MRCPs associated with wrist flexion were assessed by their gradients and by their distribution on the midline (CZ) and the ipsilateral and contralateral hand sensorimotor areas. The treatment efficacy was controlled by a decrease in PD score (Columbia University Rating Scale). The BP component was absent in four out of nine patients DN. After 3 months of treatment, BP and NS' were recorded in six out of seven patients, and the NS' slope was significantly increased in all patients. In the off phase, MRCPs from patients with on-off fluctuations did not present a BP component. In the on phase, the NS' slope was increased and the BP was recorded in two out of nine patients. These patients exhibited an earlier PD stage (Hoehn and Yahr, stage 3). These two patterns of changes in the MRCPs induced by L-Dopa treatment suggest that the BP component was recorded in patients DN when a partial resolution of the nigrostriatal activity could occur. In patients with severe fluctuations, the dopaminergic striatal pathway was more severely affected and the increase of the NS' component demonstrated the activation of extrastriatal dopamine sites within the central nervous system (limbic and cortical structures, in particular).

Adult↗

PubMed1992

[Dopa-sensitive dystonia].

Dopa-sensitive dystonia has been recognised for twenty years. It may occur in the first years of life. It first affects the lower limbs, then generalized becomes, as in torsion dystonia. Eight clinical cases are presented in five boys and three girls. The absence of the disorder in the parents, but its presence in siblings in three cases suggests that it might be recessively inherited. The symptoms are severe enough to cause major functional disability. In some cases, the intensity of the motor disorder varies during the days being, less pronounced in the morning or after a nap and more marked in the evening. Nonetheless, this feature is not constant and thus cannot be considered as an essential diagnostic criterion. Treatment with levodopa gives remarkable and durable results, but it must be continued indefinitely. Abnormal movements accompany an overdose but regress when the dosage is decreased. Unlike Parkinson's disease, it is not necessary to increase or fragment doses to avoid fluctuations in the efficacy of treatment during the day. On the contrary, after several years of the illness a decrease in daily dosage sometimes to a single dose is possible. Discontinuing treatment leads to reappearance of dystonia after two or three days. There are no established biological criteria to aid diagnosis. However, a decrease in urine levels of homovanillic acid was observed in two cases. Dopa-sensitive dystonia should be regarded as distinct from juvenile Parkinson's disease, firstly because of its symptomatology and secondly, and more importantly, because of its particular course, since fluctuations in therapeutic efficacy are never observed. It is the only known example of dopaminergic insufficiency that is chronically almost completely controlled by a modest exogenous supply of levodopa.

Carbidopa↗

PubMed1991

A comparative technetium 99m hexamethylpropylene amine oxime SPET study in different types of dementia.

Regional cerebral perfusion was evaluated by single photon emission computed tomography (SPET) using technetium 99m hexamethylpropylene amine oxime (99mTc-HMPAO) as a tracer, in 13 control subjects and 44 age-matched patients suffering from dementia of the Alzheimer's type (DAT, n = 19), presumed Pick's disease (n = 5), idiopathic Parkinson's disease with dementia (DPD, n = 15) and progressive supranuclear palsy (PSP, n = 5). HMPAO uptake was measured in the superior frontal, inferior frontal, parietal, temporal and occipital cortices, and the perfusion values were expressed as cortical/cerebellar activity ratios. As compared with controls, tracer uptake ratios in the DAT group were significantly reduced over all cortical regions, with the largest defects in the parieto-temporal and superior frontal cortices. A marked hypoperfusion affecting the superior and inferior frontal cortices was found in Pick's disease, whereas a mild but significant hypoperfusion was observed only in the superior frontal cortex of patients with PSP. In the DPD group, HMPAO uptake was significantly reduced in the parietal, temporal and occipital cortices, but not in the frontal cortex. These results show that DAT and DPD share an opposite anteroposterior HMPAO uptake defect as compared with the Pick's and PSP groups.

Aged↗

PubMed1991

The shadow of movement.

Movement is preceded, accompanied and followed by reactions which give to the primary action its correct execution and ensure that the body's axis, together with the limbs, maintains the right balance. If these reactions are interfered with, incoordination of movement, lack of balance, hypertonia or dystonia may all appear. In the case of dystonia, postural mechanisms tend to become dominant and take over from the kinetic component of movement. In the upper limbs, the dystonic posture follows patterns analogous to those used by monkeys for postural purposes. Thus, while the initial mechanisms of movement represent highly sophisticated processes thoroughly adapted to living in an upright state, the reactions that go with the movement are more primitive and probably have a less helpful role.

Animals↗

PubMed1991

Intravascular lymphomatosis (neoplastic angioendotheliosis) of the central nervous system: case report and literature review.

A 63-year-old woman developed gradual slowness, recurrent multifocal deficits, severe constitutional symptoms and hypopituitarism which progressed to death over 2.5 months. Elevation in lactico dehydrogenases was the main biological abnormality. Necropsy showed an intravascular malignant proliferation which proved to be a lymphoma of B-lineage. In order to better define diagnostic criteria, we reviewed previously reported cases of intravascular lymphomatosis of the central nervous system. A strategy for establishing the diagnosis is proposed.

Blood Vessels↗

PubMed1991

[Changes in movement-related cortical potentials in Parkinson's patients before and after treatment with levodopa].

Cortical potentials associated with voluntary, self-paced wrist flexion (MRPs) were recorded from 3 scalp locations (Cz and psi contralateral hand motor area) in patients with Parkinson's disease (9 de novo patients and 30 L-Dopa treated patients). The analysis concerned 3 components of the MRPs: the 2 slow negative shifts (NS1 and N1) before the movement onset and the motor potential (MP). The NSI amplitude was measured at Cz, the peak negativity N1 and MP from contralateral hand motor area location. The potential distribution was also studied. The amplitude of the MRPs components was the same as in the normals. But in de novo patients, the potential distribution of the NS1 component was different; a Cz preponderance of the NS1 amplitude was not found. In patients treated with L-Dopa, there is a negative correlation between the changes in amplitude and the changes in clinical rating for NS1, N1 and MP components. The decrease in the MRPs components was significant from stage III and IV of the Hoehn and Yahr scales. After L-Dopa therapy, the NS1 component from de novo patients was increased in amplitude. The amplitude of the MRPs components from patients with L-Dopa induced clinical fluctuations was reduced during "off" period in comparison to "on" period. The findings suggest that the NS1 potential and the N1 and MP components share 2 distinct systems for the control of voluntary movement. Their mechanism in Parkinson's disease is discussed.

Adult↗

PubMed1991

[Movement-related cortical potentials in aged subjects].

Cortical potentials related to freely-executed voluntary wrist flexion (MRPs) were studied in 35 subjects aged 23-80 years. The characteristics of the MPRs in aged subjects were determined in comparison data from 14 young subjects aged 23-40 years. The analysis concerned 3 components of the MRPs: the slow negative shifts (NS1 and NS2) before the movement onset and the motor potential (MP). In the aged subject, the latencies measured at Cz show a significant lengthening of the NS1 and of the duration of NS2 (NS' of Shibasaki et al, 1980). The mean amplitude of the NS1 peak at Cz is decreased, and those of N1 (the negative peak before the movement) and MP are not significantly different from those of the young subjects. The NS2 component in the aged subject (between NS1 and N1) is thus increased. In contrast to the young subjects, who present a predominance of N1 and MP amplitudes of the contralateral motor cortex over the ipsilateral cortex, the aged subjects lose lateralization of these components. Recording of MRPs with subdural electrodes (Neshige et al, 1988) shows taht NS1 results from the activity of the supplementary motor area and from the ipsi-contralateral primary motor cortex. The increase in NS2 might be interpreted as an expression of activity coming from other structures to compensate for the reduction in NS1 in the aged subject and to maintain the level of the motor potential MP.

Adult↗

PubMed1991

Spasmodic torticollis--review of 220 patients.

220 patients with isolated and idiopathic spasmodic torticollis were followed and treated over a 14 year period. Each patient was given a short questionnaire leading to the present retrospective data analysis. In most areas, including female preponderance and frequency of postural tremor, the findings confirmed previous studies and highlighted particular points: importance of psychopathological antecedents and association with stressful life-events. The discussion deals with some of the conflicting debates surrounding this unusual disorder. What is the role of psychopathological factors? What is the therapeutic prognosis? The best therapeutic results were obtained by combining anticholinergic drugs, local injections and rehabilitation.

Adolescent↗

PubMed1991

TGF-beta-like activity produced during regression of exacerbations in multiple sclerosis.

Samples representative of different stages of disease from a longitudinal study of multiple sclerosis patients were tested in the anchorage-independent growth assay for TGF-beta and an increased activity was detected in the supernatants from 2-day blood cell cultures from patients with active disease compared to patients without active disease and healthy donors. Within the group of patients with active disease, the TGF-beta like activity was significantly increased in the subgroup of patients tested during the period of regression of the symptoms where it appeared in 86.9% of the samples. These results suggest that TGF-beta or a TGF-beta like factor may play a role in regeneration processes in multiple sclerosis.

Adrenal Cortex Hormones↗

PubMed1991

(99mTc)-HM-PAO SPECT and cognitive impairment in Parkinson's disease: a comparison with dementia of the Alzheimer type.

Regional cerebral perfusion was evaluated by single photon emission tomography (SPECT) using (99mTc)-HM-PAO as a tracer, in thirty Parkinsonian patients with (n = 15) or without (n = 15) dementia, nineteen patients with dementia of the Alzheimer type (DAT) and thirteen control subjects. HM-PAO uptake was measured in the frontal, parietal, temporal and occipital cortex and tracer perfusion was expressed as cortical/cerebellar activity ratios. Regional HM-PAO ratios in nondemented Parkinsonian patients did not differ from controls, whereas in demented patients with Parkinson's disease (DPD) a significant reduction was found in the parietal, temporal and occipital cortex. Tracer uptake ratios were significantly reduced in all regions in the DAT group. Thus DPD and DAT shared a common pattern of marked posterior hypoperfusion, although the perfusion defect was greater and more extensive in the DAT patients.

Aged↗

PubMed1990

[Akinesia and associated motor involvement in Parkinson's disease and basal ganglia lesions].

The paralysis due to lesions of the cortico-spinal tract disturb movements in their different modes while dissociated paralysis result from cortical and particular biopercular lesions. Movements cannot be executed on command whereas they are accomplished in their total complexity when they accompanied certain emotional states or when they are part of an automatic activity. Such a dissociation suggest that the motor program which does not respond to voluntary command will eventually be applied thanks to emotional or affective stimuli. Basal ganglia lesions induce other symptoms. The first to be observed concern the movements and postures implied in automatic series after learning. Akinesias which results from these lesions can be partially controlled by a voluntary command, particularly when helped by sensori stimuli. Such symptoms are observed sometimes from its beginning in the Parkinson's disease. Emotion and sleep are also able to improve these akinesias: therefore they appear either on a deficitary form implying a sensitive reinforcement or on a hyperactive form, which is alleviated by hypotonia and sleep. The localized lesions of striatum or of pallidum provoke identical symptoms but at the interruption of akinesia, a distortion of movement appears, contrary to what is observed in Parkinson's disease. Mechanisms of anticipation and adjustment of postural reaction are disturbed concerning not only the body axis but also the different segments of the limbs. This disturbance provokes unsteadiness and sometimes falls. At the level of the limbs the anomaly of postural reactions slows down the movement and disturbs specially the repetitive gestures.(ABSTRACT TRUNCATED AT 250 WORDS)

Basal Ganglia Diseases↗

PubMed1989

Effect of controlled-release carbidopa/levodopa on motor performance in advanced Parkinson's disease.

Twenty parkinsonian patients were treated with controlled-release carbidopa/levodopa (Sinemet CR). All were affected by therapeutic response fluctuations related to the timing of drug administration. The daily dosage after 1 year, 766 mg +/- 250 mg, was increased by 23% compared with standard Sinemet dosage, without additional secondary effects. Parkinsonian scores improved by 43%; the prolongation of "on" periods was 63%. Nevertheless, 7 patients withdrew from this study during the 1st month of treatment. Only 1 withdrew due to an adverse reaction to the formulation, a recurrence of hallucinations. The progressive effect of the 1st morning dose and the often unpredictable time at which the product first takes effect were found to be frustrating for the other patients who withdrew. We believe that this disappointment can be avoided by giving new patients the controlled-release formulation from the start of therapy.

Administration, Oral↗

PubMed1989

[X-ray computed tomography of lumbosacral roots and primary hypertrophic neuritis (Dejerine-Sottas disease)].

CT without contrast of lumbosacral nerve roots was performed in 13 patients with peroneal atrophy and 28 control subjects. Two series of 5 mm serial sections parallel to the plane of the disk were examined at the L4-L5 and L5-S1 levels, and the transverse diameter of the S1 nerve roots measured at the lower part of the lateral recess. Results showed frank bilateral, grossly symmetrical hypertrophy of lumbosacral roots in 8 of the 13 patients. This hypertrophy involved all roots examined (L4, L5, S1), except in one case where only S1 roots were involved. Hypertrophy was often more marked on the distal part of the roots and on spinal nerves, contrasting with the sometimes normal or only slightly altered appearance of the nerve roots emerging from the dural sac. In these 8 cases, the diameter of the S1 nerve roots was 8 to 18 mm, in contrast to a mean of 3.5 +/- 1 mm in the 28 controls. CT scan images were normal in the remaining 5 patients. The presence of a CT image of nerve hypertrophy was in all cases associated with a marked fall in nerve conduction rate (median nerve motor conduction rate less than 25 msec-1), and a decrease in number of myelinated fibers with numerous onion bulbs. In contrast, the absence of CT nerve hypertrophy could not predict the results of electrophysiological and histological examinations.

Adult↗

PubMed1989

[Myasthenia and pregnancy: a clinical and immunologic study of 42 cases (21 neonatal myasthenia cases)].

Forty-two pregnancies in 39 myasthenic mothers were studied between 1978 and 1987. In 4 cases myasthenia gravis began during pregnancy and for 20 patients the clinical condition exacerbated in 15 cases, usually during the first 3 months, or during the postpartum. Except for 1 case, clinical exacerbation was controlled by anticholinesterase drug adjustment. Obstetrical problems were uncommon: abortion in 1 case and premature delivery in 4 cases. In 2 babies with severe fetal involvement polyhydramnios was present. Twenty-one babies had neonatal myasthenia gravis (NMG). In 17 cases, transient symptoms were present at delivery or shortly afterwards and full recovery occurred from a few days to 4 months. In 4 babies the clinical presentation was atypical: 1 showed a long evolution (15 months) and residual facial bilateral weakness, and three others presented fetal involvement (arthrogryposis). In these latter cases, presentation was severe with polyhydramnios, respiratory failure and long standing evolution in 2 cases (4 months and 1 year). Antiacetylcholine receptor antibodies (anti-AChR Ab) were found in all myasthenic babies and in 19 out of 20 asymptomatic babies. Maternal antibody titers were usually slightly higher than umbilical cord titers. There was a good correlation between maternal titer and onset or severity of disorder in baby. Among the 15 high titer mothers (greater than 60 nM), 13 had a myasthenic baby, 6 of them with serious disease. Conversely all low titer mothers (less than 10 nM) had a symptom-free baby. Therefore, anti-AChR Ab titration in the mother is predictive for NMG onset. Mother's myasthenia gravis severity and treatment were not correlated to the clinical condition of the newborns.

Acetylcholine↗

PubMed1988

Bilateral brain dysfunction during motor activation in type II schizophrenia measured by EEG mapping.

In this final electroencephalographic (EEG) mapping study of our series on motor dysfunction in neuroleptic-treated schizophrenic patients, we studied 10 right-handed patients with marked negative symptomatology [type II; raw score on the SANS (Munich version) 31.4 +/- 5.1]. Simple and multisensorimotor tasks involving both the dominant and nondominant hand were used for cortical activation. All tasks were referred to resting states obtained after specially designed relaxation procedures. In contrast to predominantly type I patients (SANS-MV score 12.3 +/- 4.9) of our previous EEG mapping studies, we found for resting states minor evidence (only) of increased power values in the frequency bands delta and theta. Furthermore, in contrast to signs of "left hemisphere dysfunction" and possible "compensatory right hemisphere overactivation" during motor tasks, which we discussed previously for our type I patients, we found for the type II schizophrenics a bilateral brain dysfunction. This consisted of "nonreactivity" in all frequency bands except alpha, in which, on the contrary, a "hyperreactivity" seemed to be present. In combination with evidence of bilateral hemispheric dysfunction in type II patients reported by other authors using EEG, evoked potentials, regional cerebral blood flow (rCBF) and magnetic resonance imaging (MRI) methods, this suggests that marked bilateral brain dysfunction may be correlated in schizophrenia with a clinical syndrome corresponding rather to the "negative pole" of the positive-negative dimension. In contrast, "left hemisphere dysfunction" and "signs of compensatory overactivation" seem to be linked more to a "positive" symptomatology. Finally, discrepancies of our EEG mapping and rCBF findings during motor activity suggest, speculatively, "uncoupling" between electrical and circulatory parameters in schizophrenia involving both hemispheres in type II, and predominantly the left hemisphere in type I, patients.

Adult↗