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Biomedical subjects

M Leroy

Publications and source records attributed to M Leroy.

At least 37 records · Page 2Linked to original sources
PubMed1997

Clinical and biological heterogeneity in pseudohypoparathyroidism syndrome. Results of a multicenter study.

Pseudohypoparathyroidism (PHP) is a rare inherited syndrome frequently associated with Albright's hereditary osteodystrophy (AHO). We conducted a multicenter study including 71 PHP children and 77 relatives. Erythrocyte Gsalpha biological activity was measured in each patient (normal range 85-110%). 61 patients were classified into four subtypes based on clinical and endocrine data and Gsalpha activity: 45 PHP Ia, 8 PHP Ib, 2 PHP II, and 6 PHP Ic. PHP Ia had decreased Gsalpha (58 +/- 9%), PHP Ib patients had PTH resistance, no AHO and normal Gsalpha (96 +/- 9%), PHP Ic patients had PTH resistance, AHO and no decreased Gsalpha (97 +/- 13%). The 10 remaining patients were considered to have pseudo-pseudohypoparathyroid (Pseudo-PHP) and were divided into two subtypes. One subtype had decreased Gsalpha and the second subtype had normal Gsalpha activity. The heterogeneous expression of Pseudo-PHP and thyrotropin resistance, which preceded parathyroid hormone resistance in 24% of the children, suggested that PHP might be a gradually evolving disease. GRF resistance was found in 4 out of 9 children investigated. The pedigree analysis showed PHP Ia had a dominant mode of inheritance with increased severity through generations. Pedigree analysis did not support a genomic imprinting hypothesis. Two children out of 9 had a chromosome 2 abnormality. This study confirms that Gsalpha activity is a significant marker in the diagnosis and classification of PHP.

Adolescent↗
PubMed1996

Short-term variability of blood pressure during sleep in snorers with or without apnea.

In normal subjects, the level and variability of blood pressure decrease during non-rapid eye movement (non-REM) sleep. In contrast, sleep apnea is associated with large swings in nocturnal pressure. In this study, we evaluated a computer-derived index of all-night blood pressure variability in normotensive snorers with or without sleep apnea. We also examined this index in snorers receiving medical treatment for coexistent ischemic heart disease. Beat-to-beat blood pressure was recorded with a photoplethysmographic device (Finapres) throughout polysomnography. Subjects were categorized into four groups: those without cardiovascular disease without or with sleep apnea (> or = 15 apnea plus hypopnea per hour of sleep), and those with ischemic heart disease without or with sleep apnea. A frequency distribution histogram of all increases and decreases of blood pressure according to their amplitudes was drawn and the SD of the distribution used as an estimation of variability. Mean systolic and diastolic pressures during the total sleep time were not different among the four groups. In contrast, the SD of the distribution of systolic and diastolic pressure variations that were higher in the apneic than in the nonapneic groups (P < .05) correlated with apnea plus hypopnea (P < .0001) and transient electroencephalographic arousal number per hour of sleep (P < .0001). In both apneic and nonapneic subjects, blood pressure variability as assessed by SD decreased during stages 3 and 4 of non-REM sleep compared with stages 1 and 2 and REM sleep (P < .001). Blood pressure variability was similarly increased in apneic subjects with or without ischemic heart disease. We speculate that in apneic individuals with coexistent ischemic heart disease, pressure variability that is increased despite treatment with beta-blockers or calcium antagonists may be a risk factor for acute coronary events.

Adult↗
PubMed1996

[Bronchial anastomotic complications after pulmonary transplantation. X-ray computed tomographic evaluation].

PURPOSE: To determine the sensitivity and specificity of CT in depicting bronchial anastomotic complications after lung transplantation. MATERIALS AND METHODS: A retrospective, blinded review of 105 CT scans obtained after single (n = 17) or double (n = 10) lung transplantation in 27 patients was done by two radiologists in consensus. CT images, were analyzed with respect to the status of bronchial anastomoses, with three possible answers given to the readers: normal, dehiscence, or stenosis. CT features were correlated to bronchoscopic and follow-up findings, which were considered as standard of reference. RESULTS: CT had a 60% sensitivity and 98% specificity for the diagnosis of bronchial dehiscence, and 40% and 99% for the diagnosis of anastomotic stenosis. One case of bronchial disruption was diagnosed on CT scan only and subsequently confirmed by repeated bronchoscopy. CONCLUSION: In our study, CT has a low sensitivity but a high specificity in the detection of bronchial anastomotic complications after lung transplantation. However, CT remains useful in some cases, as it can show complications not seen bronchoscopically.

Adult↗
PubMed1996

[Contribution of Doppler color ultrasonography to the screening and surveillance of ovarian hyperstimulation syndrome].

Color and power Doppler producing ovarian vascular mapping allows to realize a new functional approach of ovarian hyperstimulation syndrome (OHS); local vascular factors (ovarian angiogenesis, increase in cappillary permeability) released by hCG injection (LH effect) have in fact an important part in this syndrome. Vaginal Doppler sonography allows: -before induction, to predict potential risk of hyperstimulation: polycystic ovaries, spontaneous stromal hypervascularization; -in monitoring of ovulation stimulation, to reduce risk of multiple pregnancy and to detect early hyperstimulation, decision of hCG injection depends on number of follicles able to be fertilized (> 15 mm) and luteinized (> 10 mm); -to assess severity of OHS and search complications: ascites, hydrothorax, ovarian torsion and deep venous thrombosis. So OHS prevention imposes a monitoring by Doppler sonography and estradiol assay of all cycles induced by gonadotropins.

Female↗
PubMed1996

Determination of total mercury in estuary, lake and river sediments.

In order to improve the quality of the results in sediment analysis, the Community Bureau of Reference (BCR) of the European Communities has developed 3 sediment reference materials (CRM) from estuarine, lake and river origins. Certification of mercury content in these materials was achieved by 3 methods (cold vapor atomic absorption spectrometry, plasma emission spectrometry, neutron activation analysis with radiochemical separation). The values finally certified in the CRM estuarine, lake and river sediments are 1.77 +/- 0.06, 0.67 +/- 0.02, 1.03 +/- 0.13 mg/kg respectively.

Geologic Sediments↗
PubMed1995

Effect of manganese on the development of glial cells cultured from prenatally alcohol exposed rats.

Maternal alcohol abuse is known to produce retardation in brain maturation and brain functions. Using cultured glial cells as a model system to study these effects of alcohol we found an alcohol antagonizing property for manganese (Mn). Mn was added to the alcohol diet (MnCl2 25 mg/l of 20% v/v ethanol) of pregnant rats. Glial cells were cultured during 4 weeks from cortical brain cells of pups born to these mothers. Several biochemical parameters were examined: protein levels, enzymatic markers of glial cell maturation (enolase and glutamine synthetase), superoxide dismutase a scavenger of free radicals produced during alcohol degradation. The results were compared to appropriate controls. A beneficent effect of Mn was observed for the pups weight which was no more significantly different from the control values. Protein levels, enolase and glutamine synthetase activities were increased mainly during the proliferative period when Mn was added to the alcohol diet compared to the only alcohol treated animals. This Mn effect was not found for superoxide dismutase in cultured glial cells but exists in the total brain of the 2 week-old offspring. In the total 2 and 4 week-old brain the alcohol induced decrease of enolase and glutamine synthetase was also antagonized by the Mn supplementation. Our data suggest that Mn may act as a factor overcoming at least partially some aspects of alcohol induced retardation of nerve cell development.

Animals↗
PubMed1995

[Indications and surveillance of platelet transfusions in surgery].

Surgery, after hematology, is the biggest consumer of homologous platelet concentrates. Platelet transfusion is indicated to prevent or control bleeding associated with deficiencies in platelet number or function. In surgery, general patterns (in function of pre-surgery platelet count) can be adopted in most of the indications for platelets. In emergency situations, and in some particular cases (related to the patient, the type of operation, etc.), the transfusion procedure depends on the team's experience, the results of the available clinical and biological tests, and the drugs. Strict monitoring is required during the transfusion procedure. The efficacy of the transfusion must be controlled 1 h and 24 hours after the transfusion, and a number of factors must be assessed, namely the immunological impact of the transfusion (on red blood cells, leukocytes and platelets) and the occurrence of infectious diseases transmitted via transfusion. In addition, for a possible future transfusion, a strategy must be proposed.

Blood Loss, Surgical↗
PubMed1995

Evaluation of an ambulatory device, CID 102, in the diagnosis of obstructive sleep apnoea syndrome.

Diagnosis of obstructive sleep apnoea syndrome (OSAS) is usually performed during overnight polysomnography in the sleep laboratory. In an attempt to simplify the diagnostic strategy, we compared an ambulatory device, CID 102, with polysomnography during the same night in the laboratory in 50 consecutive patients referred for polysomnography. The CID 102 device monitors oxygen saturation, heart rate, body position and tracheal breath sounds. An acoustic pressure sensor is placed on the suprasternal notch. Signals coming from this sensor are amplified and analysed in three different channels, according to their frequency and energy. CID respiratory disturbance index is defined as the number, per hour of analysis time, of apnoeas lasting more than 10 s plus episodes of desaturation by 4% or more associated with pauses lasting from 7-10 s or snores. The polysomnographic data were recorded on paper (Reega 2000, Alvar) and analysed manually. Polysomnographic apnoea-hypopnoea index (AHIp) was defined as the number of apnoeas plus hypopnoeas per hour of sleep. The sensitivity, specificity, positive predictive value and negative predictive value of various CID respiratory disturbance index (> or = 5, > or = 10, > or = 15 and > or = 20 per hour) in diagnosing obstructive sleep apnoea syndrome were determined. When OSAS was diagnosed as AHIp > or = 15, sensitivity and specificity of a CID respiratory disturbance index > or = 5 were 73 and 62%, respectively. Positive predictive value of CID respiratory disturbance index > or = 10 for AHIp > or = 10 was 94%. CID 102 false negative patients had only hypopnoeas without any desaturation.(ABSTRACT TRUNCATED AT 250 WORDS)

Equipment Design↗
PubMed1994

Bilateral pulmonary lobe transplantation: left lower and right middle and lower lobes.

It is difficult to find lungs of appropriate size for double-lung transplantation in teenagers and small adults. Nevertheless, many young patients suffering from cystic fibrosis are waiting for lung transplantation. We have performed two bilateral lobar transplantations (left lower lobe plus right middle and lower lobe) with good recovery. Details of the technique are described.

Adolescent↗
PubMed1993

[Reproducibility of the nyctohemeral cycle of blood pressure in patients with severe Parkinson disease].

UNLABELLED: Nineteen hospitalised, severe and treated parkinsonians (9 males, 10 females), stage IV and V of Hoehn and Yahr's classification, underwent 2 days running ambulatory blood pressure monitoring (ABPM) by ABPM 630 Nippon-Colin device, during a period of therapeutic stability. Hospitalisation allowed reproducibility of daily activity. Diurnal, nocturnal and 24 hours systolic blood pressure (SBP), as well as nocturnal and 24 hours diastolic blood pressure (DBP) were reproducible with a good correlation for each patient. Diurnal diastolic BP was the lone not reproducible value but had a good day 1-day 2 correlation. [table: see text] CONCLUSION: Parkinsonian ABPM data, except diurnal DBP, are reproducible.

Adult↗
PubMed1993

[Healing of bronchial anastomoses in single and double pulmonary transplantations].

Bilateral single lung transplantation (BSLT) (the procedure of choice for double lung replacement) and single lung transplantation (SLT) have at present a low incidence of anastomotic problems. In our experience, we have recorded no death related to anastomotic problems and 4 complications occurred for 33 anastomoses with a follow up of at least 2 months. A stent was temporarily inserted for two patients. The decrease of anastomotic complications is confirmed in the literature. It is one of the reasons why the number of SLT and BSLT performed all over the world increases rapidily to the detriment of heart lung transplantation.

Adult↗
PubMed1992

Vitamin B12 among parturients and their newborns and its relationship with birthweight.

Vitamin B12 (Cobalamin) is an essential nutrient in the diet of humans, particularly during pregnancy, nevertheless very few epidemiological studies have been reported, particularly concerning variation factors. The purpose of this study is to assess the role of vitamin B12 on birthweight after taking into account potential confounders, such as obstetrical, socioeconomic, and biological factors which will be identified. This study was conducted on 188 single births occurring during a 5-month period in an obstetrical care unit in Paris. Vitamin B12 plasma levels and folate plasma levels of mothers and cords along with haematological parameters were measured. Social and obstetrical features of the mothers as well as their tobacco exposure and alcohol consumption were recorded. Cord blood vitamin B12 levels were highly correlated with maternal levels (r = 0.63, P less than 0.001) and were 2-3-fold higher. Three variation factors of vitamin B12 were identified: maternal age, ethnicity and tobacco exposure. Negative correlations between birthweight and vitamin B12 levels were observed only among the smoker group (r mothers = -0.46, P less than 0.05 and r cords = -0.42, P less than 0.05). After adjustment for ethnicity and parity, birthweight remained negatively linked to vitamin B12 in smokers. This relationship could suggest that the availability of vitamin B12 for fetal development depends on certain biological factors present only in mothers who smoked. We hypothesized this relationship could be explained, in part, by lipid metabolism, particular to smokers.

Adult↗
PubMed1992

Bilateral single lung transplantation. Complications and results in 14 patients.

Between November 1989 and April 1991, 14 bilateral single lung transplantations (BSLT) were performed at our institution using the technique we have described without omentoplasty and rarely cardiopulmonary bypass. The indications included emphysema (8), cystic fibrosis (3), infected fibrosis (1), alveolar microlithiasis (1) and lymphocytic interstitial pneumonitis (1). Maximum mean pulmonary artery pressure was 53 mmHg and minimal right ventricular ejection fraction was 15%. Two patients experienced bronchial complications: 1 complete left bronchial dehiscence, 1 late partial stenosis which required a temporary insertion of a stent. One patient had a posterior dehiscence which healed spontaneously. Five patients died postoperatively (3 of infection, 1 after a volume mismatch and 1 after a circulating anticoagulant). BSLT is the technique of choice for double lung transplantation in adults and heart lung transplantation has very few indications in infected end-stage pulmonary disease. We hope that modification of our immunosuppressive regimen will decrease postoperative mortality.

Adult↗
PubMed1992

Bronchial provocation tests in small animals: a quantified and automated procedure.

Bronchial provocation tests using aerosols in laboratory animals are difficult to standardize and quantify, because the amount of drug actually reaching the airways is unknown. To improve the quantification of aerosolized inhaled stimuli, we designed an apparatus that allows, in anesthetized intubated ventilated animals, control of temperature and hygrometry of inspired air, computerized measurement of pulmonary resistance, and fully automated delivery of a known amount of aerosolized drug directly into the trachea. Calibration of the aerosol delivery involved direct measurement of liquid delivered at the tip of the tracheal cannula. Despite all our efforts at standardization and full automation of all steps, reproducibility of aerosol delivery was poor, with stroke-by-stroke differences of 26 or 42%, according to whether an air-jet or an ultrasonic nebulizer was used. Histamine dose-response curves performed in 15 guinea pigs with this device confirmed marked differences among animals and also disclosed large intraindividual changes in bronchial responsiveness.

Aerosols↗
PubMed1992

[Donor-recipient lung volume matching in double lung transplantation. Value of left lower lobe graft].

For double lung transplantation, lung volume matching is easier comparing the predicted total lung capacities of the donor and recipient and the recipient's true TLC. The major concern in the inability to close the chest when the donor lungs are too large. The technique reported of left lower lobe implantation during bilateral single lung transplantation might be of great value in patients with small lung volume.

Adult↗
PubMed1992

[Obstructive sleep apnea syndrome in adults and cardiovascular risk].

Sleep obstructive apnea syndrome (SOAS) is a common condition with a strong male predominance. Its incidence is more than 1 percent in the population as a whole. It exists in snorers. Both snoring and SOAS are linked to the presence of abnormalities (congenital or acquired) of the upper respiratory tract. The nocturnal cardiovascular consequences of SOAS are directly linked to apnea. Bradycardia occurs during apnea and tachycardia when ventilation restarts. Paroxysmal nocturnal hypertension is a constant feature. Even in individuals who are normotensive during the day, each restarting of ventilation is accompanied by peaking of blood pressure. The pulmonary artery pressure curve follows that of systemic blood pressure. Complications begin when SOAS has been present for several years: 1) Chronic: permanent systemic hypertension is common (56 percent of SOAS). It is often refractory to antihypertensive treatment. 2) Acute: the onset of myocardial infarction and of cerebrovascular accidents explains the heavy mortality of SOAS (37 percent at 8 years in untreated individuals with a number of episodes of apnea exceeding 20 per hour of sleep). Other acute complications are less common: acute pulmonary edema, nocturnal sudden death. These events may be prevented by treatment suppressing apnea: actuarial survival curves are then superimposable upon those of the population as a whole. Thus SOAS is a cardiovascular risk factor which is remarkably reversible by specific treatment, though which most often passes unrecognized.

Cardiovascular Diseases↗