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Biomedical subjects

A Duhamel

Publications and source records attributed to A Duhamel.

At least 37 records · Page 2Linked to original sources
PubMed2001

Social and health status of arrivals in a French prison: a consecutive case study from 1989 to 1995.

BACKGROUND: To assess the demographic, socioeconomic and health status of male arrivals in French jails and to analyze the time trends of these characteristics. METHODS: The study was carried out in a prison for detained persons and short term prisoners. Using a standardized questionnaire, we recorded the characteristics of all male detainees and prisoners arriving in the prison between 1989 and 1995. The information collected concerned: demographic data, level of education and professional status, reasons for detention or imprisonment, social and family background, lifestyle, medical and psychiatric history, suicide attempts and illicit use of drugs. The characteristics of the study population were compared with those found in the general regional population. We analyzed developing trends in the health status of the prison population as well as their socio-economic profile over a period of seven years (1989 to 1995). RESULTS: A total of 14,785 questionnaires were analyzed. Of the study population, 56% had no professional qualification, and 62% was unemployed. About two-thirds of the inmates presented psychiatric problems or problems with illicit drug use (one or several drugs). Amongst these, 70% had not had any form of care -neither therapeutic nor educational- before their arrival in prison. Between 1989 and 1995, the proportion of drug users increased by 30%. A parallel increase was observed in the level of unemployment and in the frequency of mental problems. CONCLUSIONS: Our results suggest a need for therapeutic and educational care to be provided for prison inmates. This poses a problem which needs to be addressed in terms of public health. The study also illustrates the usefulness of a standardised questionnaire for each arrival. The systematic use of such a tool would make it possible to identify inmates'needs and to propose adapted care solutions.

Adolescent↗
PubMed2001

From data collection to knowledge data discovery: a medical application of data mining.

Prison inmates are exposed to a variety of major risk factors (psychiatric disorders, suicide attempts, illicit drug use). From 1986 to 1996, the USA prison population more than doubled while in France, it increased from 35655 in 1980 to 51623 in 1995. In spite of these findings, very little information concerning the inmates population is available. At the present time, there is a desire to adopt a policy based on the prevention of recidivism, on adequate release planning and referrals to community-based services. The aim of the RAPPEL project was to build an information system for assessing the social and health status of prison inmates. The pilot project was set up at the prison of Loos and allowed the collection and analysis of nearly 15000 records. The aim of this paper is to present the extension of the project consisting in developing a regional network grouping 11 jails. Information locally available will serve as the basis for the information system of regional jails. Data mining techniques will provide solutions for the extraction of new information. Three data mining tools were experimented : association rules, classification trees and clustering. Further extension consists in a distributed approach allowing direct access to the information system by WEB tools.

Classification↗
PubMed2000

Thoracic helical CT: influence of subsecond scan time and thin collimation on evaluation of peripheral pulmonary arteries.

The objective of this study was to analyze the influence of collimation on the identification of peripheral pulmonary arteries on helical CT scans. Three hundred sixty of 370 consecutive helical CT angiograms of the pulmonary circulation obtained during an 18-month investigation period were considered as technically acceptable for the detection of acute pulmonary embolism and were retrospectively analyzed. Patients in group A (n = 274) underwent CT with 2-mm collimation and pitch of 2; those in group B (n = 86) underwent CT with 3-mm collimation and pitch 1.7; a 0.75-s rotation time was systematically used. A total of 2160 segmental (six arterial zones per patient) and 2160 subsegmental (six arterial zones per patient) arterial zones were assessed. Whereas the percentage of segmental arteries was not significantly different between group A (86%) and group B (89%), the percentage of analyzable subsegmental arteries was greater in group A (65%) than in group B (43 %) (P<0.001). The causes of inadequately depicted subsegmental arterial zones were partial-volume effects (group A, n = 302; 52%; group B, n = 197; 67%; P<0.001), suboptimal enhancement (group A, n = 145; 25%; group B, n = 43; 15%; P<0.05), motion artifacts (group A, n = 113; 20%; group B, n = 30; 10%), and unincluded arteries (group A, n = 20; 3%; group B, n = 25; 8%). Helical CT with 2-mm collimation at 0.75 s per revolution enables marked improvement in the analysis of subsegmental arteries in routine clinical practice.

Adolescent↗
PubMed2000

Serum levels of inhibins are differentially altered in patients with polycystic ovary syndrome: effects of being overweight and relevance to hyperandrogenism.

OBJECTIVE: To explore the abnormalities of serum inhibin isoform concentrations in a large group of patients with polycystic ovary syndrome (PCOS) and to evaluate the influence of body mass index (BMI), age, LH, and androgens on serum inhibin levels. DESIGN: Prospective study. SETTING: Reproductive endocrinology unit of an academic medical center. PATIENT(S): Forty-one women with PCOS were compared with 24 healthy women. INTERVENTION(S): Blood sampling was performed in the early follicular phase in patients and in control women. MAIN OUTCOME MEASURE(S): Serum levels of inhibin A, inhibin B, alpha-inhibin, pro-alphaC (alpha-inhibin precursor proteins), LH, FSH, E(2), T, and androstenedione (A) were assessed in all subjects. RESULT(S): Serum alpha-inhibin levels together with LH, T, and A levels were significantly increased in women with PCOS. Serum inhibin A levels were lower in patients with PCOS than controls (median +/- SD: 7.35 +/- 2.9 vs. 9.4 +/- 4.7 pg/mL), pro-alphaC levels were higher (264 +/- 136.7 vs. 127 +/- 81.5 pg/mL), and inhibin B levels did not differ between the groups (110.5 +/- 51.5 vs. 108 +/- 47.5 pg/mL). Simple regression analysis showed that inhibin A and B levels were negatively correlated with BMI in patients with PCOS (r = -0.43 and r27 kg/m(2)) displayed significantly lower inhibin A and inhibin B levels and a higher pro-alphaC-inhibin A ratio than nonobese patients with PCOS (BMI </=27 kg/m(2)). In this last subgroup, the mean inhibin B level was significantly higher than in controls (median +/- SD: 144 +/- 53.5 vs. 108 +/- 47.5 pg/mL). Partial regression analysis, after controlling for age and BMI, demonstrated that in patients with PCOS, pro-alphaC levels were positively and independently correlated with LH and A levels. CONCLUSION(S): Among women with PCOS, the trend toward an excess serum inhibin B level is observed exclusively in nonobese patients. The higher pro-alphaC levels and the lower inhibin A levels might reflect a defect in the processing of inhibins specific to polycystic ovaries. In addition, our data suggest that pro-alphaC originates from the theca-interstitial cells and could participate in control of the androgen production by these cells.

Adolescent↗
PubMed2000

Alzheimer's disease and frontotemporal dementia are differentiated by discriminant analysis applied to (99m)Tc HmPAO SPECT data.

OBJECTIVE: Alzheimer's disease (AD) and frontotemporal dementia (FTD) are the most frequent neurodegenerative cognitive disorders. However, FTD remains poorly recognised clinically. The use of (99m)HmPAO-single photon emission computed tomography (SPECT) has been demonstrated in the differentiation of AD and FTD. Nethertheless, there are very few comparative studies designed to assess its precise value in this differential diagnosis. The aim was to determine a simple decision rule, deduced from statistical analysis, which, if applied to regions of interest (ROIs) and mini mental state examination (MMSE), could improve the predictive value of SPECT in differential diagnosis between AD and FTD. METHODS: Forty patients, 20 with probable AD and 20 with probable FTD were included. All patients underwent brain SPECT imaging, after an intravenous injection of (99m)Tc HmPAO-(555mBq). For each patient, 20 ROIs were determined on the Fleishig's slice and their activity was normalised to the mean cerebellar activity. Bivariate analysis (Wilcoxon rank tests) and multivariate analysis (stepwise discriminant analysis) were performed to determine the subgroup of variables able to give the highest predictive value for this differential diagnosis. A simple decision rule was built from a predictive score derived by factorial discriminant analysis. RESULTS: As previously described, the fixation defect was found in frontal regions of interest (ROIs) in FTD and in the left temporoparietal-occipital ROIs in AD. Among the 21 variables, five were finally selected: right median frontal, left lateral frontal, left tempoparietal, left temporoparietal-occipital areas, and MMSE. One hundred per cent of patients with FTD were correctly classified by the decision rule (20/20 patients) and 90% of patients with AD (18/20). CONCLUSION: AD and FTD are differentiated by SPECT. Automatic classification based on a decision rule deduced from factorial discriminant analysis could enhance its performance.

Alzheimer Disease↗
PubMed2000

Helical CT angiography of thoracic outlet syndrome: functional anatomy.

OBJECTIVE: The objective of this study is to determine the anatomic characteristics of the thoracic outlet in symptomatic patients before and after postural maneuver. SUBJECTS AND METHODS: Seventy-nine symptomatic patients (61 female patients [group 1]; 18 male patients [group 2]; mean age, 38 years) underwent helical CT angiography of the thoracic apices in the neutral position and after a postural maneuver, enabling the evaluation of the functional anatomy of the musculoskeletal and arterial structures of the ipsilateral thoracic outlet. RESULTS: A statistically significant difference was found between the distribution of the distances (maximum and costosubclavian) measured in the neutral position and after postural maneuver in groups 1 and 2. The median value of these distances was smaller after postural maneuver in groups 1 and 2. A statistically significant difference was found between the distribution of the distances (maximum and costosubclavian) measured in patients of group 1 with arterial stenosis and in patients of group 1 without arterial stenosis. A slight indentation of the anterior wall of the subclavian artery when it arches around the anterior scalene muscle was observed in 39 patients (64%) in group 1 and in 11 patients (61%) in group 2 in the neutral position, in 19 patients (31%) in group 1 and in six patients (33%) in group 2 after the postural maneuver. The predominant positional changes of the vascular structures were the posteroanterior displacement of the subclavian vessels observed in groups 1 and 2, the arch made by the subclavian artery above the first rib in 40 patients (66%) in group 1 and nine patients (50%) in group 2, and the posterior displacement of the axillary artery observed in 36 patients (59%) in group 1 and in 12 patients (67%) in group 2. CONCLUSION: Helical CT shows significant narrowing of the costoclavicular space after postural maneuver in symptomatic patients.

Adolescent↗
PubMed2000

Clinical value of thin collimation in the diagnostic workup of pulmonary embolism.

OBJECTIVE: We report our experience with thin-collimation helical CT in a population of patients suspected of having pulmonary embolism. CONCLUSION: Thin-collimation helical CT provided technically acceptable examinations for pulmonary embolism in 360 patients (97%). In this population, CT revealed pulmonary embolism in 104 patients (29%), negative findings in 217 patients (59%), indeterminate findings in 39 patients (10%), and alternative diagnoses in 65% of patients with negative or inconclusive findings. Ventilation-perfusion scanning and Doppler sonography of the lower extremities were performed in 158 (44%) and 133 patients (37%), respectively, whereas pulmonary angiography was performed in 27 patients (7.5%). The estimated false-negative rate of helical CT was 5%.

Adolescent↗
PubMed1999

Neuropsychological abnormalities in first degree relatives of patients with familial Parkinson's disease.

OBJECTIVE: To investigate the cognitive profile of first degree relatives of patients with familial Parkinson's disease to determine whether these subjects presented signs of neuropsychological dysfunction compared with healthy controls. Results of recent genetic and neuroimaging studies suggest a genetic contribution to the aetiology of Parkinson's disease and underline the interest in identifying preclinical signs of the disease. METHODS: A battery of tests evaluating executive function was administered to 41 first degree relatives of patients with well documented familial Parkinson's disease and 39 healthy controls. A factorial discriminant analysis allowed isolation of a subgroup of 15 first degree relatives who could be considered as impaired compared with the healthy controls. Among these 15 "deviant" relatives, nine performed globally worse than the control subjects on all tasks. The six other subjects had mean or even high scores on all task variables, except on those highly correlated with the discriminant score of the factorial discriminant analysis. RESULTS AND CONCLUSION: Among the first degree relatives of patients with familial Parkinson's disease, some manifested executive dysfunction comparable with that typically associated with the disease. Such impairment could represent a preclinical form of Parkinson's disease.

Adult↗
PubMed1999

Technetium HMPAO SPECT study in dementia with Lewy bodies, Alzheimer's disease and idiopathic Parkinson's disease.

UNLABELLED: The aim of this study was to compare the regional cerebral blood flow measurements studied by SPECT in dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) to determine the contribution of SPECT to the differential diagnosis of these two diseases. METHODS: SPECT analysis with 99mTc-hexamethyl propyleneamine oxime (HMPAO) was performed in 20 patients with probable DLB, 20 patients with probable AD and 20 patients with idiopathic Parkinson's disease (IPD). Ten pairs of regions of interest were analyzed. Tracer uptake was expressed as a corticocerebellar activity ratio. RESULTS: Compared with IPD, in the DLB group there was a global decrease of HMPAO uptake in cortical regions of interest except in the posterior frontal and occipital regions; in the AD group there was limited left temporal and parietal hypoperfusion. In the DLB group, frontal HMPAO uptake was significantly lower than in the AD group. Two predictive scores were established by a factorial discriminant analysis from six left cortical indices (medial frontal, lateral frontal, posterior frontal, temporoparietal, parietal and parietooccipital) and the Mini-Mental State Examination, which correctly classified 53 of 60 patients (88%) (DLB, 18 of 20; AD, 16 of 20; IPD, 19 of 20). CONCLUSION: These findings indicate the presence of diffuse cortical abnormalities in DLB and suggest that SPECT may be useful in discriminating in vivo DLB from AD, revealing mainly frontal hypoperfusion in the former group. We estimate that SPECT study increases the possibility of separating DLB and AD because both disorders share different patterns of cerebral blood flow abnormality.

Aged↗
PubMed1999

[Neurological examination and brain computed tomography in the initial staging of non-small-cell lung cancer: a prospective study].

Brain metastases occur in 17 to 40% of lung carcinoma and 30 to 60% of brain metastases originate from a lung carcinoma. Brain metastasis directly influences prognosis and treatment of lung cancer. The aim of this study was to prospectively compare the findings of the neurological examination performed by a neurologist and results of double dose delayed computed tomography (CT DDD). The neurologist and radiologist were blinded to each other's results. Patients included had non-small-cell lung cancer (NSCLC) and were neurologically asymptomatic with no other cancer. From November 1993 to May 1996, 135 patients were included (126 men and 9 women). Ninety neurological examinations were normal, 34 suggested brain metastasis and 11 were abnormal but did not suggest brain metastasis. One hundred thirteen CTs were normal, 1 showed a brain metastasis and 11 were abnormal but did not evidence brain metastasis. The sensitivity, specificity, positive predictive value and negative predictive value of the neurological examination were 73, 79, 23 and 97% respectively. The presence of brain metastasis was directly related to tumor stage but not to age or histology. We suggest that brain CT DDD should be performed in stage IIIA, IIIB, IV whereas in stage I or II, the neurological examination is sufficient. However, a larger number of patients would be required to confirm these findings.

Adult↗
PubMed1999

[112 cases of sporadic and genetically determined pheochromocytoma: a comparative pathologic study].

The aim of this study was to compare 64 genetically determined pheochromocytomas (PH) (49 MEN IIa, 3 MEN IIb, 6 Von Recklinghausen diseases, 1 von Hippel-Lindau disease, 5 familial pheochromocytomas) and 48 sporadic PH. Genetically determined PH were more often observed among men and more frequently bilateral and multicentric than sporadic PH. Sporadic tumors had more often adrenal capsular invasion, necrosis and pseudocysts. Genetically determined PH were more differentiated with an insular pattern, hyaline globules and a higher percentage of polyhedric cells. Sporadic tumors were less differentiated with more frequently a diffuse pattern and small cells. Adrenal medullar hyperplasia was significantly associated with genetically determined PH. Adrenal cortical hyperplasia was not associated with a particular type of PH. The PS100 and chromogranin immunodetection was equivalent in both groups.

Adrenal Cortex↗
PubMed1999

A prototype of an information system for assessing the health status of prison inmates.

A research-action program was established in 1996 between the Loos-Lez-Lille prison psychiatric unit and the Department of Medical Informatics of the University Hospital of Lille (France):--(1) to investigate the health status and the general characteristics of the prison population--(2) to develop an Information System for improving the prison health care and to facilitate social rehabilitation of convicts. Starting off 1988, all new prisoners are interviewed on their arrival using a standard questionnaire. The transfer of all the information recorded in this questionnaire into a computer base was initiated in 1996, when the research action program began. A statistical analysis was performed on 15,200 records (1989-1995) to identify the most informative parameters: 50% of inmates were less than 24 years old; 57% were unemployed; 60% had no professional qualification. 31% of inmates had a psychiatric history and 16% had made a previous suicide attempt. The rate of drug abuse has increased from 24% in 89 to 53% in 95. To analyze the time trends of these parameters, a prototype of Information System was then developed. The system uses the database to product standard reports in real time.

Adolescent↗
PubMed1998

Influence of chronic administration of L-DOPA on event-related desynchronization of mu rhythm preceding voluntary movement in Parkinson's disease.

The spatiotemporal pattern of event-related desynchronization (ERD) during the motor preparation period preceding a self-paced voluntary wrist-flexion was compared in two groups of 10 right and 10 left hemiparkinsonian patients, before and after chronic administration of L-DOPA. ERD was computed in the 9-11 Hz frequency band from 11 source derivations covering the medial frontocentral, central and parietocentral areas, during two successive left and right experimental conditions (100 self-paced wrist flexions). In the two groups ERD appeared with a shorter latency over the contralateral primary sensorimotor area, when the movements were performed with the akinetic hand. After L-DOPA administration, earlier ERD onset before the movement was observed in both groups over the contralateral and ipsilateral central and parietocentral areas. A medial frontocentral ERD distribution was also observed before the onset of movement, especially in the right hemiparkinsonian group. Delayed ERD onset, which shows that programming of movement is affected in Parkinson's disease, may be partially corrected by L-DOPA therapy.

Antiparkinson Agents↗
PubMed1998

No resuscitation orders and withdrawal of therapy in French paediatric intensive care units. Groupe Francophone de Réanimation et d'Urgences Pédiatriques.

OBJECTIVE: To determine the incidence of different modes of death in French paediatric intensive care units and to compare patients' characteristics, including a severity of illness score (Paediatric Risk of Mortality: PRISM score) and prior health status (Paediatric Overall Performance Category scale), according to the mode of death. DESIGN: A 4-month prospective cohort study. SETTING: Nine French multidisciplinary paediatric intensive care units. PATIENTS: All patients who died in PICUs, except premature babies. MAIN RESULTS: Among 712 admissions, 13% patients died. Brain death was declared in 20%, failure of cardiopulmonary resuscitation occurred in 26%, do-not-resuscitate status was identified in 27%, and withdrawal of supportive therapy was noted in 27%. The PRISM score and the baseline Paediatric Overall Performance Category were not different between the four groups. Brain-dead patients were older than those in whom a do-not-resuscitate order and withdrawal of therapy were made (median age 81 vs 7 and 4 months). CONCLUSIONS: Decisions to limit or to withdraw supportive care were made for a majority of patients dying in French paediatric intensive care units. Chronic health evaluation and severity of illness index are not sufficient to describe dead-patient populations.

Brain Death↗
PubMed1998

Brain-behaviour relationships. Some models and related statistical procedures for the study of brain-damaged patients.

The study of brain-damaged patients provides the opportunity to examine the anatomy of brain functions, and has been renewed by the development of structural neuroimaging. Despite the development of neuroimaging and neuropsychological assessment, major uncertainties persist on the exact delimitation of the brain areas involved in specific processes, and these contribute to the enduring controversies over the effective lesions associated with neuropsychological disorders. These uncertainties are mainly due to the methods used in the study of brain-behaviour relationships, which frequently rely on a group comparison design. The aim of this study was to provide models for the study of brain-behaviour relationships and to assess the reliability of related statistical procedures. In the present work, four theoretical modes of brain-behaviour relationship consistent with neuropsychological data are put forward: unicity, equivalence, association and summation. The first experimental study was based on a simulated population of patients. Lesions associated with the occurrence of a deficit were predetermined according to modes of brain-behaviour relationship and were compared with lesions selected by statistical analysis. The study showed that (i) the group comparison design did not allow determination of the effective lesion, (ii) stepwise regression analysis was sensitive to the relative frequency of lesions, especially when the occurrence of a deficit depended on two lesions, but did not allow determination of the mode of brain-behaviour relationship, and (iii) the classification tree test described the data very satisfactorily and permitted the determination of the mode of brain-behaviour relationships. In order to assess the validity of statistical analyses, a second study was performed in which lesion locations associated with motor weakness in stroke patients were examined. Selected lesions were compared with the anatomy of the human motor system. The study mainly showed that (i) the stepwise regression analysis of selected lesions was not related to the presence of a motor deficit, and (ii) the classification tree test provided perfect agreement with motor weakness predicted by lesion locations and suggested an equivalence mode of brain-behaviour relationship consistent with current neurological knowledge. These studies provide models of brain-behaviour relationships and related statistical procedures that may allow more precise documentation of the anatomy of brain functions and its pathology, and further investigation of the modalities of brain-behaviour relationships.

Behavior↗
PubMed1998

Volume rendering of the tracheobronchial tree: clinical evaluation of bronchographic images.

PURPOSE: To evaluate the application of the volume-rendering technique to airway disease. MATERIAL AND METHODS: Seventy-four spiral computed tomographic (CT) examination (1- to 5-mm section thickness; pitch, 1.7-20.0) were performed for known or suspected abnormality of the airways, including (a) benign tracheobronchial stenosis (group 1, n = 47), (b) complex airway lesions (group 2, n = 15), and (c) bronchiectasis (group 3, n - 12). Two radiologists independently compared overlapping transverse CT scans and volume-rendered bronchographic images for detection of airway abnormalities and identification of lesion morphology and extent, with bronchoscopic correlation. RESULTS: Bronchographic image quality was graded as excellent (73%) or good (24%), whereas motion-related artifacts led to poor image quality in 3% of cases (trapezoid parameters included window width of -700 to -350 HU, triangular trapezoid shape, parenchymal opacification of 70%, unshaded algorithm). Compared with transverse CT scans, volume-rendered images (a) provided supplemental group 3, even, seven), (b) improved confidence in the interpretation of congenital airway abnormalities in six cases (8%) (all from group 2), and (c) corrected interpretive errors in four cases (5%) (group 1, two cases; group 2, two). CONCLUSION: Volume-rendered images improved the recognition of mild changes in airway caliber and the understand of complex tracheobronchial anomalies.

Adolescent↗