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Biomedical subjects

P Rondot

Publications and source records attributed to P Rondot.

At least 55 records · Page 3Linked to original sources
PubMed1987

Auditory perception of music measured by brain electrical activity mapping.

The brain electrical activity of right-handed normal subjects was studied while they were exposed to auditory stimulation of the music type. The material presented was a note, a scale and a melody, recorded on magnetic tape. Each stimulus condition lasted 45 sec. The first 30 sec were analysed using brain electrical activity mapping in the delta (1-4 Hz), alpha (8-12 Hz) and beta 2 (18-24 Hz) frequency bands. The results showed significant bilateral reaction differences for all conditions, showing a left midtemporal activation predominance for the note and scale conditions, but a right midtemporal and frontal predominance for the melody. The results are discussed in terms of functional specialization for different levels of processing.

Adult↗
PubMed1987

Therapeutic response to progabide in neuroleptic- and L-dopa-induced dyskinesias.

The results of two trials conducted in human dyskinesia with progabide, a specific gamma-aminobutyric acid (GABA) receptor agonist, are reviewed. In one trial, 13 parkinsonian patients with L-DOPA-induced dyskinesia (LDD) and "on-off" fluctuations were included in a double-blind controlled trial progabide versus placebo. No change was observed during this trial in the severity of dyskinesia on progabide treatment but the drug significantly extended the "on" period as compared with placebo. In the second trial, 20 patients with neuroleptic-induced dyskinesia (TD) entered an open dose ranging trial with progabide. Fourteen of the 16 patients who completed the trial had a good-to-excellent therapeutic response. According to these results, progabide does not seem to have the same therapeutic benefit in LDD as TD. These data suggest that the hypothesis of a dopaminergic supersensitivity as a similar pathogenic substrate for both clinical conditions should be reconsidered. If this hypothesis remains the most consistent to explain the occurrence of LDD, the therapeutic effect of progabide in TD is an argument for an implication of the GABAergic system in the appearance of TD.

Adult↗
PubMed1987

A comparative evaluation of the short orientation memory concentration test of cognitive impairment.

In order to assess the relative sensitivity and specificity of Katzman's short orientation memory concentration test (OMCT), 89 non demented patients and 44 patients affected by vascular or degenerative dementia were consecutively evaluated by three different mental status tests. The OMCT appeared equivalent to the Mini Mental State Examination in identifying dementia. Optimum sensitivity and specificity, respectively 88% and 94%, were achieved by a 10/11 cut-off score, giving a 11% false positive rate. Among patients with Alzheimer's disease, the OMCT score was correlated with mean values of a simple reaction time. It was also correlated with the Wechsler global MQ and the orientation, logical memory and paired associates items of the scale. There was no relationship between the OMCT score and the coloured Progressive Matrices IQ. The OMCT was reliable when given at 1 month interval. Serial evaluations did not show any significant practice effect.

Adult↗
PubMed1987

Clinical trial of Madopar HBS in parkinsonian patients with fluctuating drug response after long-term levodopa therapy.

23 parkinsonian patients, 11 men and 12 women with an average age of 62 +/- 10 years, were recruited for an open substitution study of standard Madopar by Madopar HBS (hydrodynamically balanced system). All patients were presenting fluctuations in efficacy associated or not with abnormal involuntary movements. The patients in this study had been suffering from Parkinson's disease for 16 +/- 6 years and were severely disabled (Hoehn and Yahr grade III-V). The substitution was carried out dose for dose from one day to another. During the first month the dosage titration was aimed at finding the optimal therapeutic effect. After 120 days 13 patients were continuing the treatment while 10 had stopped it because of lack of therapeutic advantage. After 120 days, as compared to the initial state, end-of-dose fluctuations improved by 47%, the parkinsonian symptomatology by 54% and the abnormal involuntary movements improved by 33%. The daily dose of Levodopa had to be increased from 580 +/- 230 to 710 +/- 240 mg. The results obtained were excellent in 5 cases, good in 6 and moderate in 2 cases.

Aged↗
PubMed1987

Peripheral neuropathies during hypoxaemic chronic obstructive airways disease.

Peripheral nervous system alterations during chronic obstructive airways disease (COAD) with respiratory insufficiency seem more frequent than usual neurological practice would suggest. Almost a third of COAD patients have clinical evidence of peripheral neuropathy and two thirds have electrophysiological abnormalities. The presentation consists of a polyneuropathy often subclinical or with predominantly sensory signs, which has the neurophysiological and pathological features of predominantly axonal neuropathy. The presumed etiopathogenic factors are multiple: chronic hypoxia, tobacco smoke (which contains at least three neurotoxic constituents) alcoholism, malnutrition and adverse effects of certain drugs. Hypoxia probably plays the leading part, either by direct action on nerves fibres or by enhancing the effects of other neurotoxic factors or deficiencies.

Alcohol Drinking↗
PubMed1987

[Controlled release levodopa-benserazide and changes in efficacy during treatment of Parkinson's disease].

Twenty-five patients, 12 men and 13 women, 42 to 79 years (mean 62) were studied to determine possible interest of a controlled release preparation of L. dopa combined with benserazide. All patients were experiencing fluctuations in efficacy over the last 8 +/- 4 years. Their Parkinson disease was of long duration, (16 +/- 5 years), severe (Hoehn and Yahr's stages III to V) and treated with L. dopa for 12 +/- 4 years. Results were evaluated in the short, medium and long term. During the initial period the new treatment was substituted for previous therapy on a dose for dose basis. Long term (300 days) results showed that "end of dose" fluctuations had been improved in 40 p. 100 of cases without concomitant reduction in therapeutic effects, duration of "ON" periods progressing by 60%. The frequency of drug intake was unaltered but daily dosage could be increased by 30% without increasing severity of abnormal movements to a similar degree. The administration of this new presentation can be recommended, especially when frequent fluctuations compromise long term therapeutic effects.

Adult↗
PubMed1987

Postural adjustments associated with rapid voluntary arm movements in patients with Parkinson's disease.

To determine the extent to which deficits in coordination between posture and movement are influenced by postural disorders, postural adjustments associated with rapid voluntary arm movement were studied in PD patients and controls. EMG activity in postural muscles of the lower limbs and the trunk and local anteroposterior accelerations of the upper part of the leg were recorded in subjects who rapidly raised their arms to a horizontal position in response to a visual signal. The arm movement was characterized electromyographically by EMG activity from the deltoid muscle (anterior portion) and kinetically by acceleration of the arm. Study of characteristics of voluntary movement showed a nonsignificant increase in RT (simple-reaction time task) and an important increase in MT. There were important differences between PD patients and control subjects with regard to postural adjustments. Timing between voluntary movement and postural movement was anticipatory in 5% of PD patients, whereas it was anticipatory in 100% of control subjects. In PD patients, organization of early postural adjustments was not specific to voluntary movement; in control subjects, organization of early postural adjustments was specific to the forthcoming movement. Last, a possible functional relation between the "quality" of postural adjustments and a reduction in motor performance of normal subjects is suggested.

Adult↗
PubMed1986

Patients with Alzheimer's disease show an increased content of 15 Kdalton somatostatin precursor and a lowered level of tetradecapeptide in their cerebrospinal fluid.

The relative proportions of both somatostatin-14 and its precursors somatostatin-28 and the 15 Kdalton prosomatostatin were evaluated by radioimmunoassay in the cerebrospinal fluid of patients with Alzheimer's disease. It was observed that the patients have a lowered content in the tetradecapeptide somatostatin while they exhibit a significant increase in unprocessed 15 Kda precursor. These results indicate that these patients possess impaired processing mechanisms which may be responsible for the lowered content in mature somatostatin-14. These observations may provide a valuable test for the ante-mortem diagnosis of the disease. They are discussed in connection with others suggesting that Alzheimer's patients may be selectively altered in their somatostatinergic neurones of their cerebral cortex (Morrison et al. (1985) Nature 314, 90-92. Roberts et al. (1985) Nature 314, 92-94).

Aged↗
PubMed1986

[Assay of anti-acetylcholine receptor antibodies in myasthenic syndromes of newborn infants].

Eighteen neonates were investigated for antibodies directed against acetylcholine receptors. No antibody was detected in 3 cases of congenital myasthenic syndrome, whereas positive results (3.5 to 250 nM) were obtained in 7 cases of transitory neonatal myasthenia and in 7 of 8 asymptomatic infants born to myasthenic mothers. The neonatal antibodies are fully cleared within 1 to 6 months (half-life: 9 days to 2 and a half months). The prognostic value of the maternal and infantile antibody titers is limited: maternal titer at the end of pregnancy, though usually higher in the mothers of myasthenic children, do not predict or preclude the occurrence of transitory myasthenia, and there is no clear correlation between the severity and duration of the myasthenia and the initial titer or the level of the child's antibodies. The assay which measures antibodies against acetylcholine receptors is useful in that it confirms the diagnosis of transitory myasthenia and excludes congenital myasthenic syndromes.

Amniotic Fluid↗
PubMed1986

EEG mapping of left hemisphere dysfunction during motor performance in schizophrenia.

With a newly developed system of brain electrical activity mapping we studied 10 right-handed, neuroleptic-treated schizophrenics (five of the disorganized, five of the paranoid type, corresponding to 295.1 and .3 in DSM-III), compared with 10 normal controls. Increasingly complex motor tasks were used for cortical activation, all functional states being referenced to resting states recorded after a special relaxation program. We found higher delta and theta amplitudes during rest, as noted in previous studies, and lower beta power values. As a major result, however, we found a widespread left hemisphere dysfunction in schizophrenics, predominantly in the left primary sensory and motor areas. Additionally, we found signs of a "compensatory" overactivation in patients in motor tasks, when this hemisphere is not "used" by normal persons. The results support our findings obtained with this method during multisensory motor coordination in schizophrenia. The results in these patients suggest that these are not merely vigilance, attention, or motivation dysfunctions, but rather specific cortical correlates of impaired motor performance.

Acute Disease↗
PubMed1986

Somatostatin-like immunoreactivity and acetylcholinesterase activities in cerebrospinal fluid of patients with Alzheimer disease and senile dementia of the Alzheimer type.

Somatostatin-like immunoreactivity (SLI) and acetylcholinesterase (AchE) activities were measured in the cerebrospinal fluid of 25 patients with senile dementia of the Alzheimer type (SDAT). Both SLI levels and AchE activities were reduced in the CSF of SDAT patients. The SLI levels and AchE activities were not correlated with the duration and the dementia score. However, in two patients the CSF SLI concentration was in agreement with the SLI levels in the frontal cortex obtained by biopsy. Our findings suggest that CSF SLI may be a good index of cortical SLI activities.

Acetylcholinesterase↗
PubMed1986

Motor responses measured by brain electrical activity mapping.

The brain electrical activity of right-handed normal subjects was studied while they were exposed to motor performance tasks that were of increasing difficulty. Each task lasted 45-60 s, and a 30-s period of each task was analyzed by a spectrum analyzer. Data are presented in topographic maps showing the electrical activity for each task, in delta (1-4 cycles [c]/s), alpha (8-12 c/s), and beta 2 (18-24 c/s). The results showed a bilateral decrease in amplitude in sensorimotor areas relative to baseline, for a single hand movement. Tasks that required the programming of movement showed baseline/task differences in amplitude in additional areas; the right frontal area, the prefrontal area, the posterior parietal area, and the left temporal area. The results obtained suggest that different topographical areas are involved in motor tasks that require increased level of programming.

Brain Mapping↗
PubMed1986

Severe chorea after acute carbon monoxide poisoning.

Ten days after an acute exposure to carbon monoxide, a 33-year-old woman exhibited severe chorea. CT scan revealed bilateral lucencies of the pallidum and anterior arm of the internal capsule. Chorea was successfully treated by chlorpromazine and did not relapse after treatment withdrawal. The mechanism of chorea in acute carbon monoxide poisoning is discussed.

Adult↗
PubMed1986

Ageing and Parkinson's disease.

Based on the examination of 400 patients suffering from Parkinson's disease, the main symptoms of motor and brain ageing have been underlined. Motor ageing is evidenced by the importance of akinesis, while rigor and quaking are limited, and by the arrival of dystonic attitudes which tend to last. Brain ageing is revealed by memory disturbances, mental disorders and delusions without phasic or praxis troubles. The comparative study of different types of dementia did not allow clinical or anatomopathological confirmation.

Aged↗
PubMed1986

[Bilateral thalamic infarcts with abnormal movements and permanent amnesia].

A 45 year-old woman with mitral valve disease developed bilateral thalamic infarcts presenting as vigilance disorders, with mutism and downwards gaze paralysis during several days, followed by involuntary rhythmic movements over 13 days. These movements affected the four limbs with a rhythm variable with time as alternate or synchronized agonist-antagonist periods. Subsequent examinations demonstrated global, lasting amnesia and a subclinical disorder of vertical ocular movements. Repeat CT scan confirmed the presence of bilateral anterior thalamic infarcts affecting polar and/or paramedian territories. Emphasis is placed on the similarity of the abnormal movements in this case with L-dopa induced involuntary movements.

Amnesia↗
PubMed1986

[Clinical recovery from Isaacs' syndrome].

A patient with Isaacs' syndrome (previously reported in 1966) has been clinically normal since 1972. The possibility of an outcome of this type has been reported by Isaacs and Heffron (1974) and in subsequent reports. This does not provide an explanation for the syndrome of continuous muscle fiber activity but constitutes an additional clinical feature.

Adult↗
PubMed1985

[Agenesis of the corpus callosum in a man with complete mosaic trisomy 8].

The coexistence in an epileptic patient of a radiologically confirmed agenesis of the corpus callosum and other somatic abnormalities, notably skeletal, prompted us to perform a karyotype which showed an extra chromosome 8. The trisomy 8-callosal agenesis association is not exceptional, but it may easily be missed owing to the absence or scarcity of clinical signs of the cerebral malformation. We would suggest that patients with confirmed agenesis of the corpus callosum should be investigated for trisomy 8 and conversely, that patients with trisomy 8 detected during examination for a characteristic malformative syndrome should be systematically investigated for abnormality of the neocortical commissure.

Adult↗