PubMed Health⌕ Search

Biomedical subjects

G Le Moël

Publications and source records attributed to G Le Moël.

At least 19 recordsLinked to original sources
PubMed2006

Serum carotenoids, vitamins A and E, and 8 year lung function decline in a general population.

BACKGROUND: Oxidative stress is thought to have a major role in the pathogenesis of airway obstruction. A study was undertaken to determine whether subjects with low levels of antioxidants (serum beta-carotene, alpha-carotene, vitamins A and E) would be at a higher risk of accelerated decline in forced expiratory volume in 1 second (FEV1) as their lungs would be less protected against oxidative stress. METHODS: 1194 French subjects aged 20-44 years were examined in 1992 as part of the European Community Respiratory Health Survey (ECRHS); 864 were followed up in 2000 and 535 (50% men, 40% lifelong non-smokers) had complete data for analysis. RESULTS: During the 8 year study period the mean annual decrease in FEV1 (adjusted for sex, centre, baseline FEV1, age, smoking, body mass index and low density lipoprotein cholesterol) was 29.8 ml/year. The rate of decrease was lower for the subjects in tertile I of beta-carotene at baseline than for those in the two other tertiles (-36.5 v -27.6 ml/year; p = 0.004). An increase in beta-carotene between the two surveys was associated with a slower decline in FEV1. No association was observed between alpha-carotene, vitamin A, or vitamin E and FEV(1) decline. However, being a heavy smoker (> or =20 cigarettes/day) in combination with a low level of beta-carotene or vitamin E was associated with the steepest decline in FEV1 (-52.5 ml/year, p = 0.0002 and -50.1 ml/year, p = 0.010, respectively). CONCLUSIONS: These results strongly suggest that beta-carotene protects against the decline in FEV1 over an 8 year period in the general population, and that beta-carotene and vitamin E are protective in heavy smokers.

Adult↗
PubMed2001

Diagnostic value of ferritin and glycosylated ferritin in adult onset Still's disease.

OBJECTIVE: To determine the usefulness of serum ferritin and glycosylated ferritin (GF) levels in diagnosing adult onset Still's disease (AOSD). METHODS: We performed a retrospective multicenter study of 205 patients who had ferritin and GF assays in one hospital laboratory. Records of all patients were reviewed, and a standardized questionnaire used to extract all data available at the time of the assay. The clinicians' final diagnosis was also recorded. Patients were classified as having "certain AOSD" (based on Yamaguchi's criteria) or a control disease. The concordance of ferritin and GF levels with final diagnosis was evaluated. RESULTS: In total 49 AOSD and 120 control patients were eligible. The mean ferritin value was significantly higher in the AOSD group (4,752 +/- 9,599 microg/l) than in the control group (1,571 +/- 3,807 microg/l), p = 0.029. GF was significantly lower in AOSD patients (15.9 +/- 11.9%) than in the control group (31.5 +/- 18.7%), p < 0.001. The combination of a GF level of < or = 20% with ferritin above the upper limit of normal yielded a sensitivity of 70.5% and specificity of 83.2%. The combination of a GF level < or = 20% with ferritin 5 times normal produced a sensitivity of 43.2% and specificity of 92.9%. This latter combination allowed an AOSD diagnosis to be ruled out for 6 of the 8 control patients who met Yamaguchi's positive criteria. CONCLUSION: Ferritin and GF levels are powerful diagnostic markers of AOSD. They may be helpful in clinical practice for excluding differential diagnoses.

Adult↗
PubMed2001

[Quality control of capillary blood measurements in clinical services: follow up by the biologist].

In Bichat-Claude Bernard Hospital, the study of capillary glucose analyzers in the aim of uniformizing the selection of glucose meters, has shown the relevance of a standardized handling in order to obtain clinically interpretable results. It has been necessary to implement a quality follow up by the biologist. In the first stage, the biochemistry laboratory, with the clinical service supervisor and the supplier, has assured the training of the medical staff habilitated to use the meters and to carry out a quality control. In the second stage, the biologist implemented a monthly control on a total blood control sample, the stability of which has been checked after the necessary addition of glucose. Dosing of that sample, which is used as an external control, is carried out in parallel by the QID Precision glucose analyzer (Abbott) and by the portable Hemocue B Glucose (Vermed), which is selected as a comparison standard. This allows a monthly control of the accuracy of the meter. The condition of the equipment, as well as the weekly control follow up, validated by the nurse, is registered on a sheet prepared by the biologist. In partnership with Vermed, we have developed a processing software of the data stored in the Hemocue, allowing the automatic issue of a report summarizing the equipment condition and the data of weekly and monthly controls follow up. This report, signed by the biologist, is sent to every Service Manager and Supervising Nurse. On the basis of our one year experience, this practice has generated an efficient collaboration between the clinical services and the biochemistry laboratory, allowing to keep the quality of the capillary glucose measurements performed in inpatients.

Blood Chemical Analysis↗
PubMed2000

Percentage of glycosylated serum ferritin remains low throughout the course of adult onset Still's disease.

OBJECTIVE: To determine the evolution of levels of total serum ferritin and percentage of the glycosylated form in patients with adult onset Still's disease (AOSD) at the time of diagnosis and during follow up. METHODS: All patients with AOSD were tested at the time of diagnosis and during follow up. Total serum ferritin levels were analysed by immunoassay, and the percentage of glycosylated ferritin was determined by methods using Sepharose-Con A. RESULTS: 14 patients (eight women, six men) with AOSD were enrolled. At the time of diagnosis, mean (SD) age was 36 (16) years. Mean initial total serum ferritin was 6350 (1300) microg/l (normal <250 microg/l). The mean initial percentage of glycosylated ferritin was 14.7 (13)% (normal >50%). Mean follow up time was 37 (35) months. At the time of the last examination all patients were in remission except one, who presented a chronic articular form. Total serum ferritin remained high in this single patient and was normal in the 13 others, with a mean of 98 (73) microg/l. In all patients the percentage of glycosylated ferritin remained low, with a mean of 16 (16)%. CONCLUSION: Total serum ferritin is a marker of the active phase of AOSD. The percentage of glycosylated ferritin is low both in the active phase and in remission. Further studies are needed to confirm these data and to determine their specificity for AOSD before considering any possible use of a low percentage of glycosylated ferritin as a diagnostic tool in suspected AOSD, especially when atypical or previously treated.

Adolescent↗
PubMed1999

[Acute respiratory Chlamydia pneumoniae infections in adults. Value of direct gene amplification diagnosis].

Chlamydia pneumoniae has been established recently as an important human respiratory pathogen. The aim of this study was to define the incidence of Chlamydia pneumoniae in acute respiratory infections by evaluating its presence in posterior nasopharyngeal aspirates or broncho-alveolar lavage specimens by polymerase chain reaction-hybridization (PCR-EIA) as well as the titres of specific antibodies in serum by a rELISA test and a micro-immunofluorescence (MIF) test. 68 adults patients were investigated. Eight patients (11.8%) were positive by either rELISA or PCR-EIA or both, with an infection rate of 5 patients with community-acquired pneumonia, 2 asthmatic patients and 1 patients with an exacerbation of chronic obstructive pulmonary disease. Serological evidence of acute infection was found in four of these patients with rELISA test and in three others with MIF test. PCR-EIA detected Chlamydia pneumoniae DNA in four patients, but there were concordant results with rELISA and PCR-EIA in only one patient. In conclusion, Chlamydia pneumoniae appears to be a common etiologic agent of acute respiratory infections in adults. The discrepancy between serological test and PCR-EIA results reflects the difficulties in routine laboratory diagnosis of Chlamydia pneumoniae. The ambiguous results of serological tests from a single serum sample assess the utility of PCR for prompt diagnosis. When PCR is negative or no feasible, a second serology to 15/21 days of interval is necessary. Further studies with optimised techniques must be developed.

Acute Disease↗
PubMed1995

[Factors of gastroesophageal acid reflux in severe obesity].

OBJECTIVE: To study in morbid obesity the relationship between the degree of gastro-oesophageal reflux (GER) and the excess of body weight, or the related factors such as the energy intake or the fat distribution (waist-hip ratio). METHODS: In 20 morbid obese subjects (body weight: 125 +/- 32 kg) consulting in a weight-loss programme, anthropometric measurements, 3-hr oesophageal pHmetry, double isotope labelled meal for studying gastric emptying, study of gastric acid and pepsin secretions using PEG 4,000 as marker, and upper endoscopy were performed. RESULTS: Nine out of the 20 patients had more than 10 GER per 3-hr period. Seven patients had at least one GER symptom per day. In 6 patients, pH was under 4 for more than 10% of the time. The total number of GER and the number of GER of more than 5 min duration were correlated to the body mass index (P = 0.016 and P < 0.05 respectively). The number of GER was also correlated to the android type of overweight (P < 0.03). These relationships persisted when sex, age, smoking, and obesity complications (such as diabetes) were taken into account. There was a positive correlation between the number of GER and energy and lipid intake (energy intake: 3,119 +/- 1,082 kcal/day; P < 0.003 for both). The degree of GER was positively related to basal acid output (P = 0.049), and to sham feeding-stimulated acid output (P = 0.05); it was negatively related to gastric emptying half time, but was not correlated with basal or stimulated pepsin output. A relationship was found between body mass index (BMI) and gastric emptying half time for solid (P = 0.002) and liquid phases (P = 0.001). CONCLUSION: GER seems to be common in long lasting morbid obesity. The number of refluxes increased with waist/hip ratio, BMI and energy or fat intake. GER was also increased by decreased gastric emptying rate, which was in part determined by BMI. The real prevalence of GER in morbid obeses must be determined by a large prospective study.

Adult↗
PubMed1995

[Determination of serum or plasma alpha-tocopherol by high performance liquid chromatography: optimization of operative models].

A previous multicentric study set up by the Société française de biologie clinique has emphasized the usefulness of a standardized procedure for the determination by high performance liquid chromatography of alpha-tocopherol in serum or plasma. In our study, we have tested every step of the different published procedures: internal standard adduct, lipoprotein denaturation and vitamin extraction. Reproducibility of results was improved by the use of tocol as an internal standard when compared to retinol or alpha-tocopherol acetates. Lipoprotein denaturation was more efficient with ethanol addition than with methanol and when the ethanol/water ratio was > or = 0.7. Use of n-hexane or n-heptane gave the same recovery of alpha-tocopherol. When organic solvent/water ratio was > or = 1, n-hexane enabled to efficiently extract, in a one-step procedure, the alpha-tocopherol from both normo and hyperlipidemic sera. Performances of the selected procedure were: detection limit: 0.5 microM--linear range: 750 microM--within run coefficient of variation: 2.03%--day to day: 4.76%. Finally, this pluricentric study allows us to propose an optimised procedure for the determination of alpha-tocopherol in serum or plasma.

Chromatography, High Pressure Liquid↗
PubMed1994

[Stability of alpha-tocopherol: pre-analytical conditions in its determination in blood samples].

Incomplete and controversial data exist concerning vitamin E or alpha-tocopherol stability in biological samples. Recent clinical interest in the protective function of alpha-tocopherol provided another reason for the setting-up of a multicenter study by the Sociéte Française de Biologie Clinique. Our purpose was to examine the effects on alpha-tocopherol stability, firstly, of collection and transportation of blood samples, and, secondly, of the temperature (-20 degrees C and -80 degrees C) and period of storage of serum or plasma. alpha-tocopherol was determined in serum or plasma by isocratic liquid chromatography with UV detection at 292 nm. Our results established that alpha-tocopherol was extremely stable in blood, serum or plasma over 8 hours without special handling conditions (light, temperature). Pools of serum or plasma were stable for at least 3 months at -20 degrees C and -80 degrees C. They are suitable for use in the quality control of alpha-tocopherol. On the other hand, in some samples, we observed great variability in the rate of alpha-tocopherol degradation. However, there was lesser degradation when these plasma samples were stored at -80 degrees C instead of -20 degrees C. We therefore do not advise storing serum or plasma for more than 1 month at -20 degrees C for more than 3 months at -80 degrees C. This latter temperature is recommended in epidemiological studies.

Adult↗
PubMed1984

[Renal clearance technic for individualizing lithium dosage in routine hospital care].

Lithium has a narrow therapeutic index and exhibits a wide pharmacokinetic variability. Individual dosage regimen adjustment is necessary to warrant the efficacy and safety of long-term treatment. We propose the "renal clearance method" for rapid determination of the lithium carbonate daily dose for chronic therapy. After the first intake of drug by a manic-depressive patient, a four-hour trial is performed. It involves two blood samplings and two urine collections, in which lithium and creatine are assayed. Comparison of observed creatinine with a value predicted according to age, morphological characteristics, sex and serum creatinine of the patients allows the interpretation of conflicting results. The estimation of lithium and creatinine clearances of each patient is performed using a computerized or manual method which unfolds a decision procedure. The daily dosage (1.5 to 6 250 mg tablets in two or three daily intakes) is deduced from the according lithium renal clearance (0.4 to over 2 l/h) by means of a nomogram established in previous studies on about 50 patients. The clearance method has been investigated in routine hospital care on a 40 patients sample. The range of satisfactory lithium serum levels during patients monitoring was 0.6-0.9 mmol/l. Accurate dosage regimen forecasting is obtained in 92% of the patients. The percentage observed in a subset of 13 patients with the C24 method, which relies on a unique blood sample 24 hours after the first dose, was much lower (54%). The renal clearance method appears as a robust and reliable technique for individual lithium dosage regimen adjustment in routine care.

Adult↗
PubMed1983

Study of carbohydrate material isolated from ultrafiltrates in patients with chronic renal failure.

We have isolated substances of molecular weight ranging between 350 and 2,000 daltons from ultrafiltrates of 3 patients treated by maintenance haemodialysis for chronic renal failure. Such substances might have a role in the genesis of uraemic toxicity. We have chiefly studied their carbohydrate content. Material was fractionated according to a procedure previously used to urine in healthy controls. Consecutive ion exchange, charcoal Celite and paper chromatography lead to the isolation and purification of oligosaccharides, glycopeptides, glucuronoconjugates and peptides. The different classes of carbohydrate material present in dialysis fluids from uraemic patients are close to those formed in normal urines. All the oligosaccharides in renal failure urine had have identified in normal urine. In a previous studies we have demonstrated that the levels of glucuronoconjugates are higher in the blood of uraemic patients. The glucuronoconjugates and their aglycones could have a toxic effect but a great part of them is removed by hemodialysis.

Carbohydrates↗
PubMedDate not supplied

[Carotenoids: 1. Metabolism and physiology].

Carotenoids are a family of pigments with at least 600 members. They derive from lycopene after steps of cyclisation, dehydrogenation and oxidation. It is their chemical structure that determines their physiochemical properties and, in part, their biological activities. About 50 carotenoids can be found in human diet and about 20 of them have been found in plasma and tissues. There is no RDA (Recommended Daily Allowance) for carotenoids. Quantities of carotenoids in diet are difficult to estimate, partly because methods used for the establishment of food composition tables were not specific and sensitive enough. Also, given values do not always take into account variations due to season and region of culture. Absorption of beta-carotene in humans has been the subject of numerous studies but only very little is known about other carotenoids. In general, absorption depends on bioavailability from the food matrix and solubility in micelles. After absorption through passive diffusion, carotenoids follow the chylomicrons metabolism. They are taken up by the liver and released in the blood stream in lipoproteins (VLDL). Carotenoids with no-substituted beta-ionone cycles (alpha and beta-carotene and beta-cryptoxanthin) have provitamin A activity. Highest activity has been found for all-trans beta-carotene. Not all steps of vitamin A biosynthesis and metabolism of other carotenoids have been clarified yet. Besides their provitamin A activity, carotenoids have numerous biological functions. They are efficient scavengers of free radicals, particularly of 1O2. In vitro they have been shown to protect LDL. However, results in vivo are inconsistent. Other functions include enhancement of gap junctions, immunomodulation and regulation of enzyme activity involved in carcinogenesis.

Absorption↗
PubMedDate not supplied

[Vitamins and aging].

Explore the source record for details and available documents.

Age Factors↗