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M C Bourdel

Publications and source records attributed to M C Bourdel.

At least 37 records · Page 2Linked to original sources

[Method of simulation and choice of factors in the analysis of principal components].

OBJECTIVE: There are many methods to determine how many components should be retained in principal components analysis. This choice can be made on the basis of arbitrary (Kaiser) or subjective (Interpretable factors) criteria. This work presents the simulation criteria of Lébart e Dreyfus. The method create a matrix of randomized numbers and a principal component analysis is performed on the basis of this matrix. The components extracted from this data represent the cut off values. Those that exceed this cut off value should be retained. As an example, a principal component analysis is performed with the Hamilton depression rating scale (17 items) on a sample of 130 subjects. RESULTS AND CONCLUSION: The Simulation method is compared with the Kaiser method and is shown that the Simulation method maintains the components clinically significant.

Depression↗

Sensitive assay of thyroid stimulating hormone in depressed patients.

A decreased thyroid stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH) has been noted in major depression. Some authors found a positive correlation between baseline TSH levels and TSH response to TRH, especially with sensitive assays of TSH. Serum TSH was assayed by a sensitive method in 55 depressed patients and 38 healthy volunteers. Patients were subclassified according to DSM-III as suffering from major depression (n = 40) and non-major depression (n = 15). The patients' mean score on the Hamilton Rating Scale for Depression (HRSD) was 50 (SD = 10). The TSH value was significantly lower in depressed patients compared with healthy control subjects, and in major compared with non-major depression. No differences in TSH levels distinguished the various subtypes of major depression. There was a significant negative correlation between global HRSD scores and TSH concentrations. The most anxious patients tended to have significantly lower TSH values compared with the least anxious subjects. Total HRSD insomnia scores correlated negatively with TSH concentrations after log transformation. The sensitive determination of TSH may also provide an index of thyroid function in depression that is simpler to implement than measurements of the TSH response to TRH.

Adult↗

Factorial structure of the 17-item Hamilton Depression Rating Scale.

The Hamilton Depression Rating Scale was applied to 60 depressed inpatients diagnosed using the Composite International Diagnostic Interview. The information to rate the scale was obtained with a semistructured interview to standardize the scale administration method. Items were factorized using principal components analysis with Varimax rotation. Three factors were obtained with the simulation method, accounting for 47% of variance. The first includes the core symptoms of depression. The symptoms of patients having an isolated mood disorder were compared with those having comorbidity with other diagnoses. The comorbidity did not affect the first factor but modified the second factor (anxiety) and the third factor (insomnia).

Adult↗

Maintenance ECT in intractable manic-depressive disorders.

Twenty-two patients suffering from intractable recurrent unipolar or bipolar mood disorders were enrolled in a maintenance-ECT protocol (ECT-M) for more than 18 months, with a treatment at approximately monthly intervals. Eleven have continued treatment for > 2 years. Whereas 44% of the year had been spent in the hospital with at least three episodes a year prior to ECT-M, only 7% of the year was spent in the hospital during ECT-M with only one relapse every 16 months requiring admission (p < 0.001). Forty-five percent of the patients were in full remission and 27% in partial remission according to DSM-III-R criteria. ECT-M responsiveness of rapid-cyclers and delusional depressed patients usually drug refractory has been very encouraging with full or partial remission for 100% of rapid-cyclers and 80% of delusional depressed patients.

Adult↗

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↗

[Quantified EEG in the diagnosis of Alzheimer's type dementia].

79 subjects (mean age 70.2 ans, 31 males, 48 females) selected as probable dementia of the Alzheimer type, at the early stage of the disease and 17 normal aged people (mean age: 72.2, 5 males, 12 females) were recorded with a 16 channel computerized-EEG (C-EEG) with topographical analysis of the observed changes and with classical visual analysis of the EEG. Quite simple C-EEG parameters as mean dominant frequency (MF) and alpha to theta ratio are able to discriminate patients from normal with a greater accuracy than visual analysis. The values of 8.6 for the MF and 1.3 for the alpha/theta ratio are proposed as cut off values between normal and DAT patients. The topographical analysis appear to be of no additional usefulness in the discrimination of the two groups.

Aged↗

[Comparison of SPECT and quantified EEG features in Alzheimer's type dementia].

Forty-one patients with probable dementia of the Alzheimer type (DAT) have been studied by computerized EEg (C-EEG) and single photon emission tomography (SPECT) using 123-IMP. Four groups have been distinguished according to SPECT hypoperfusion topography: frontal, temporo-parietal, fronto-parietal and fronto-temporo-parietal. C-EEG parameters were much more disturbed in the 2 latter than in the 2 former groups. Thus a normal C-EEG could indicate a dominant frontal or temporo-parietal form of DAT. Therefore some bias due to duration or rate of disease progression cannot be excluded. So far the important finding is that EEG changes are diffuse and do not reflect the topography of SPECT hypoperfusion questioning the value of EEG topographical analysis in DTA.

Aged↗

[EEG value for the prediction of the evolution of Alzheimer's type dementia].

Twenty patients selected as probable dementia of the Alzheimer type (DAT) have been examined two times during a mean follow-up period of 14.5 months. Two groups have been distinguished at the end of this period: a cognitively impaired one and a stable one. EEG features at T1, at T2 or the difference T1-T2 does not allow an accurate and predictive discrimination between the two groups. But we cannot conclude that EEG is useless for prediction of the rate of progression of the disease in DAT because most of the cognitively stable patients are also stable for mean frequency. So mean frequency could be an interesting marker of evolutivity but this to be tested with more patients including more subjects reaching the severe stage of dementia.

Aged↗

[Topographical analysis of endogenous evoked potentials in depressed old people and in patients with Alzheimer's type dementia].

Latencies, amplitudes and localization of the maximum of the peaks of late onset evoked responses have been studied in 3 groups of elderly people: normal, depressed and demented (probable dementia of Alzheimer type DAT) at the early stage of the disease. Evoked responses with an auditory oddball paradigm have been recorded with 16 electrodes in 2 situations: counting the target sounds, and motor response with measurement of the reaction time. No difference in amplitude was observed between the 3 groups. Only a significant difference for P3 latency was observed between the DAT and the depressed groups and only in the counting situation. The maximum P3 response was most often found on the anterior areas in the DAT group and in the posterior areas in the normal and depressed groups. The topographic localization of the P3 peak could therefore be of some help in the characterize of subjects with probable DAT at the early stage of the disease.

Aged↗

(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↗

Comparison of acetorphan with clonidine for opiate withdrawal symptoms.

OBJECTIVE AND METHOD: The authors compared the effects of acetorphan, an enkephalinase inhibitor, with those of clonidine for the treatment of the opioid withdrawal syndrome. Nineteen patients addicted to heroin or synthetic opiates who were undergoing drug withdrawal and displayed a withdrawal syndrome according to DSM-III criteria were studied for 5 days in a hospital setting. In a double-blind trial, 10 subjects were given acetorphan intravenously and nine were given clonidine; objective signs and subjective symptoms of withdrawal were recorded. RESULTS: On several objective signs, the effect of acetorphan was more marked than that of clonidine, whereas the two drugs exhibited similar efficacy with respect to the subjective components of withdrawal. No side effect was noted in the subjects who received acetorphan. CONCLUSIONS: Enkephalinase inhibition may constitute a novel and safe therapeutic approach to the opioid withdrawal syndrome.

Adolescent↗

[Clinical, electrophysiologic and endocrine effects of the perfusion of high doses of TRH in amyotrophic lateral sclerosis].

Eight patients with amyotrophic lateral sclerosis received 500 mg TRH by IV infusion, at a progressive rate during 3 hours. Only 3 patients noted subjective improvement of strength. Clinical muscular testing and H response study failed to show any change. Moreover modifications of the prolactin, growth hormone, TSH and T3 serum levels raise a question concerning the tolerance with long term utilization of TRH.

Acetylcholinesterase↗

[Longitudinal study of the relation between environmental conditions and the health of patients in a long-stay hospital].

A longitudinal survey has been conducted for a 30-month period in the long-term care hospital of Ivry, in Paris urban area. 1500 people were medically monitored daily by the doctors who were in charge of each unit of the hospital; each individual pathological event was exactly recorded, with complete development. This follow-up permitted to report 6300 acute illnesses. Environmental physical parameters (NOx, SO2, particulates, temperature, humidity, atmospheric pressure) were recorded indoors and outdoors during the whole period. The relation of environmental conditions to health has been studied with the cross-correlations method, applied to respiratory disease incidence rates and physical parameters series. It appeared that only NOx was significantly related to an increase of respiratory disease incidence rates.

Aged↗

[Effect of atmospheric pollution (SO2--dust) and meteorological conditions on mortality in Paris between 1969 and 1976].

The short-term effect of environmental factors (atmospheric pollutants, meteorology) on mortality are studied with 8 years of continuous daily data collected in Paris (1969-1976). Mortality data are specified using daily-rate of death, according to diagnosis and age-range. Chosen pollutants are acidity and smoke. Meteorological conditions are identified by synoptic data and local parameters (pressure, temperature, humidity). Relations between mortality and pollution, and their interaction with meteorological conditions, have been described with several statistical methods. Among results, it is shown for example that relation of pollution levels with total daily deaths is not very clear but it becomes very significant for very old population; the strongest relation occurs for deaths connected with respiratory diseases, with a maximum 2 or 3 days after, but possibly later. Climatic factors such as synoptic situation and temperature have also influence on mortality but not so significant as pollution.

Aged↗