Search

This is a translation of the paper “Recommendations for the application and follow-up of quality controls in medical biology laboratories” published in French in the journal Annales de Biologie Clinique (Recommandations pour la mise en place et le suivi des contrôles de qualité dans les laboratoires de biologie médicale. Ann Biol Clin (Paris). 2019;77:577-97.). The recommendations proposed in this document are the result of work conducted jointly by the Network of Accredited Medical Laboratories (LABAC), the French Society of Medical Biology (SFBC) and the Federation of Associations for External Quality Assessment (FAEEQ). The different steps of the implementation of quality controls, based on a risk analysis, are described. The changes of reagent or internal quality control (IQC) materials batches, the action to be taken in case of non-conform IQC results, the choice of external quality assessment (EQA) scheme and interpretation of their results as well as the new issue of analyses performed on several automatic systems available in the same laboratory are discussed. Finally, the concept of measurement uncertainty, the robustness of the methods as well as the specificities of near-patient testing and rapid tests are described. These recommendations cannot apply for all cases we can find in medical laboratories. The implementation of an objective alternative strategy, supported with documented evidence, might be equally considered.

The recommendations that we formulate in this document come from LABAC, SFBC and FAEEQ. They describe the different steps from the initial application of quality controls, based on risk analysis: the changes of reagent batches or internal quality controls (IQC) batches, the course when IQC are not in accordance with references, the choice of external quality evaluation and the interpretation of its results, the comparability of results obtained in several analysers used in the same laboratory. Lastly, measurement uncertainty, robustness of methods and specificities of near-patient biology and rapid tests are described. Note that these recommendations cannot develop all cases that we could find in laboratories. It remains necessary to carry out an objective strategy, supported with documentary evidences.

BACKGROUND: Hemolysis, Icterus, and Lipemia constituting the HIL index, are the most common causes of interference with accurate measurement in biochemistry. This study focuses on bilirubin interference, aiming to identify the analyses impacted and proposing a way to predict nominal interference‐free analyte concentrations, based on both analyte level and Icterus Index (I (ict)). METHODS: Sixteen common analytes were studied: alanine aminotransferase (ALT), albumin (ALB), alkaline phosphatase (ALP), amylase (AMY), aspartate aminotransferase (AST), total cholesterol (CHOLT), creatinine (CREA, enzymatic method), fructosamine (FRUC), gamma‐glutamyl transferase (GGT), HDL cholesterol (HDLc), total iron (Iron), lipase (LIP), inorganic phosphorus (Phos), total protein (PROT), triglycerides (TG), and uric acid (UA). Both the traditional 10% change in concentrations from baseline and the Total Change Level (TCL) were taken as acceptance limits. Nineteen pools of sera covering a wide range of values were tested on the Cobas® 6000 (Roche Diagnostics). I (ict) ranged from 0 to 60. RESULTS: Eight analytes increased (FRUC and Phos) or decreased (CHOLT, CREA, HDLc, PROT, TG, and UA) significantly when I (ict) increased. FRUC, HDLc, PROT, and UA showed a linear relationship when I (ict) increased. A non‐linear relationship was found for TG, CREA, and for CHOLT; this also depended on analyte levels. Others were not impacted, even at high I (ict). CONCLUSIONS: A method of estimating an interference‐free value for FRUC, HDLc, PROT, Phos, UA, TG, and CREA, and for CHOLT in cases of cholestasis, is proposed. I (ict) levels are identified based on analytical performance goals, and equations to recalculate interference‐free values are also proposed.

The main objective of this study was to evaluate the contamination by mercury (Hg), methylmercury (Me-Hg), cadmium (Cd), selenium (Se), zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn) in dolphins stranded on the French Mediterranean coast. The distributions of these contaminants in the organs of dolphins have also been studied. Overall, contamination levels varied according to the following sequence: liver > kidney > lung > muscle, except for cadmium (kidney > liver > lung > muscle). Size and sex of animals were also considered. Young dolphins were less impacted with trace elements than adults, except for copper. Among the studied parameters, the most important appeared to be the size of mammals. In addition, in the case of mercury and selenium, the sex of mammals seemed to be also relevant. The correlations between the concentrations of trace elements suggest the existence of detoxification processes. Since 1990s, using dolphins for tracing marine pollution, a slight reduction in the burden of the considered trace elements could be noted.

International audience; Background: Most people require dietaryvitamin D to achieve the recommended concentration of 25-hydroxyvitamin D [25(OH)D] in the blood. However, the response to vitamin D supplementation is highly variable among individuals. Objective: We assessed whether the variability in cholecalciferol bioavailability was associated with single-nucleotide polymorphisms (SNPs) in candidate genes. Methods: In a single-group design, 39 healthy adult men with a mean +/- SD age of 33 +/- 2 y and mean +/- SD body mass index lid kg/m(2)) of 22.9 +/- 0.3 were genotyped with the use of whole-genome microarrays. After an overnight fast, plasma 25(OH)D status was measured, and the subjects then consumed a meal that provided 5 mg cholecalciferol as a supplement. Plasma chylomicron cholecalciferol concentration was measured over 8 h, and cholecalciferol response was assessed by calculating the postprandial area under the curve. Partial least squares regression was used to test the association of SNPs in or near candidate genes (61 genes representing 3791 SNPs) with the postprandial cholecalciferol response. Results: The postprandial chylomicron cholecalciferol concentration peaked at 5.4 h. The cholecalciferol response was extremely variable among individuals (CV: 47%). It correlated with the chylomicron triglyceride (TG) response (r = 0.60; P < 0.001) but not with the fasting plasma 25(OH)D concentration (r = 0.04; P = 0.83). A significant (P = 1.32 x 10(-4)) partial least squares regression model that included 17 SNPs in 13 genes (including 5 that have been associated with chylomicron TG response) was associated with the variance in the cholecalciferol response. Conclusion: In healthy men, there is a high interindividual variability in cholecalciferol bioavailability that is associated with a combination of SNPs located in or near genes involved in both vitamin D and lipid metabolism. This trial was registered at clinicaltrials.gov as NCT02100774.

Introduction et but de l’etude Une part significative de la vitamine D presente dans l’organisme humain est produite au niveau de la peau par exposition a la lumiere ultraviolette. Neanmoins, pour obtenir ou maintenir un statut en vitamine D satisfaisant, une majorite d’individus doit consommer de la vitamine D, soit incluse dans l’alimentation, soit sous forme de supplements. Il a ete montre que la reponse sanguine a la supplementation en vitamine D presentait une forte variabilite interindividuelle. En outre, le transport de la vitamine D est en partie dependant de proteines. Enfin, nous avons montre que la biodisponibilite d’autres micronutriments lipidiques (tocopherol, luteine, lycopene et beta-carotene), qui possedent des mecanismes d’absorption en commun avec le cholecalciferol (D3), etait en partie modulee par des polymorphismes mononucleotidiques (SNPs) dans des genes impliques dans le transport intestinal de ces micronutriments et dans le metabolisme des chylomicrons. L’objectif principal de cette etude etait donc d’identifier des SNPs associes avec la variabilite interindividuelle de la biodisponibilite de la D3. Materiel et methodes Trente-neuf hommes adultes en bonne sante ont ete genotypes a l’aide de puces a ADN genome entier. Ils ont consomme un repas contenant 5 g de D3 sous forme de supplement. La concentration en D3 et en calcifediol (25(OH)D) dans les chylomicrons plasmatiques a ete mesuree a intervalles de temps reguliers jusqu’a 8 h apres le repas. L’association entre des SNPs dans des genes impliques dans le metabolisme de la vitamine D et des lipides (61 genes candidats representant 3791 SNPs) et la reponse postprandiale en D3 dans les chylomicrons a ete analysee par regression des moindres carres partiels (regression PLS). Resultats La concentration postprandiale en D3 des chylomicrons a atteint son maximum 5,4 h apres le repas. Nous n’avons pas observe de variation significative de la concentration postprandiale en 25(OH)D des chylomicrons. La reponse postprandiale en D3 dans les chylomicrons presentait une forte variabilite interindividuelle (CV = 47 %). Cette reponse etait positivement correlee a la reponse postprandiale en triglycerides (r = 0,60, p Conclusion Chez des hommes adultes en bonne sante, on observe une forte variabilite interindividuelle de la biodisponibilite de la D3. Cette variabilite est associee avec une combinaison de SNPs dans des genes impliques dans le metabolisme de la vitamine D et des lipides.

This study evaluated the distribution of polychlorinated biphenyls (PCBs) in 39 surface sediment samples and four cores collected in Toulon Bay, a semiclosed area submitted to various anthropogenic inputs. The concentration of PCBs in the superficial sediment samples ranged from 1.7 to 2530 ng g−1 dry weight. The spatial distribution of these compounds suggested that the high concentrations of these contaminants are located in the small bay and are related to human activities. In the larger bay, the concentrations were in the same order of magnitude than those reported in others locations around the world. Comparison of the levels with target values from the French legislation shows that, except for four polluted sites with critical values (N2: values ≥1 mg kg−1 dry weight) in the smaller bay, PCBs levels throughout the larger and the smaller bay are lower than the accepted values (N1: values

We described a simple and rapid method to quantify simultaneously chlorhexidine (CHD) and its major metabolite, para Chloroaniline (pCA) by HPLC with UV detection without the additional need of mobile-phase amine modifiers or ion-pairing reagents, with good resolution between pCA and CHD, symmetry peak of the compound and short run time. HPLC-UV analyses were performed using a Dionex® Summit liquid chromatograph (Dionex Corp, Sunnyvale, CA, USA). Chromatographic separations were carried out on a Luna® 150 mm×3 mm i.d. column packed with 3 µm CN (cyano) particles (Phenomenex®), guarded by an on-line filter. Mobile phase consist of methanol:water with sodium chloride with 0.02% of formic acid (55:45). Wavelengths for pCA and for CHD are 238 and 255 nm respectively. Influence of methanol and of sodium chloride content in the eluant has been studied. Linearity of CHD is very good, from 0.5 up to 21.2 µg/l while linearity of pCA is in the range of 0.05 to 10 µg/l with correlation coefficients above 0.999. Resolution between the components is above 4, asymmetry is about 1.3 and 1.7 for pCA and CHD respectively and the run time is less than 5 minutes. This method has been applied to CHD solution of different medical devices. No interference has been reported, and the analysis of direct injection of solution, without any treatment is achieved in less than five minutes.In conclusion, we present a validated method for dosage of CHD and its major impurity pCA, known to be carcinogen, available into medical products or medicinal device for in-vitro diagnostic.

Aims To determine plasma levels of apoprotein (apo) C-II and apoprotein C-III in Type 2 diabetic patients and to examine the clinical and biological factors that are associated with elevated apoC concentrations. Methods We measured apoC-II and apoC-III in total plasma and in non-high-density lipoprotein fractions by an immunoturbidimetric assay in 88 Caucasian Type 2 diabetic patients and in 138 healthy control subjects. Results Plasma levels of both apoC-II and apoC-III were increased in Type 2 diabetic patients. The clinical conditions associated with an increase of plasma apoC-II and apoC-III were abdominal obesity, body mass index, poor glycaemic control and lack of insulin treatment. However, when multivariate analysis was used, plasma apoCs levels correlated with triglyceride levels only. The apoC-III ⁄ apoC-II ratio was similar in the Type 2 diabetic and control subjects. Conclusions Our study shows the parallel increase of apoC-II and C-III in Type 2 diabetic patients. This parallel increase is related to hypertriglyceridaemia only. Diabet. Med. 26, 736–739 (2009)

The high density lipoprotein Anionic Peptide Factor (HDL(3)-APF) was previously described as an apolipoprotein that promotes the reverse cholesterol transport. Since phospholipid transfer protein (PLTP) is involved in such mechanism we attempted to focus on the two APF and PLTP proteins.We recruited 56 type 2 diabetic patients with (n=36) or without (n=20) coronary artery disease (CAD) and 19 CAD patients. The three groups were compared to 39 healthy control subjects. In all groups, lipid profile was determined and plasma APF concentrations and PLTP activity were measured.In all patients, the PLTP activity was significantly increased in comparison with controls (p0.01), in concomitance with a plasma APF level decrease in groups with CAD (with and without type 2 diabetes) (p0.01). Multiple linear regression analysis demonstrated that, when apoA-I, HDL-C, HDL-phospholipids and PLTP activity were taken into account as independent variables (after univariate regression analysis), HDL-PL was positively and independently related to APF (p0.0001 in whole population; p=0.0090 in controls) and PLTP activity was negatively and independently related to APF in whole population and all patients' groups (all p0.05), but positively and independently associated to APF in controls (p=0.0005).APF could be considered as a specific marker against CAD and type 2 diabetes mellitus and our results confirm the atherogenic behavior of PLTP in CAD. Thus, these two proteins are likely to be regulated in a reverse manner.

This study was designed to determine if bronchoalveolar lavage (BAL) quantitative culture results can be used confidently for the diagnosis of bacterial ventilator-associated pneumonia (VAP) without taking dilution into account.Prospective observational cohort study.A 12-bed medical ICU in a teaching hospital.A total of 241 BAL (three 50-mL aliquots) were performed in 127 patients presenting a suspicion of VAP.All consecutive adults who were ventilated more than 48 h were included if VAP was clinically suspected. A dilution factor, k, was developed according to the formula: dilution factor k = concentration of urea in plasma/concentration of urea in lavage fluid recovered. Using this dilution factor, the quantitative bacterial counts were interpreted accordingly with a corrected positive threshold at 10(5) colony forming unit (CFU) mL(-1).Eighty-nine BAL with at least one micro-organismor = 10(4) CFU mL(-1) were identified (37%). In 176 BAL (73%), k ranged from 10 to 100. Median k was 24.4 (9.7-40.2) in VAP group and 24.6 (13.1-57.8) in patients without pneumonia (NS). Among the 25 BAL with micro-organism counts of 10(4) CFU mL(-1), 3 had a dilution factor lower than 10, resulting in corrected counts below the threshold of 10(5) CFU mL(-1). Two out of 15 patients with micro-organism counts of 10(3) CFU mL(-1) had corrected micro-organism counts of 10(5) CFU mL(-1). Finally, only five BAL (2.1%) were misclassified when the dilution correction factor was applied.Using urea as dilution factor, we showed that BAL dilution variations did not alter the interpretation of BAL quantitative bacterial culture when administrating three aliquots of 50 mL of saline.

The interindividual variation in ApoE plasma concentration is considerable, mainly determined byapoEgenotype and sex. However, a large amount of variability remains unexplained by these factors. We have evaluated whether the quantity and quality of dietary fat interacts with theapoEgenotype and sex modifying ApoE plasma levels in young healthy subjects. Eighty-four volunteers (sixty-six apoE3/3, eight apoE4/3 and ten apoE3/2) were subjected to three dietary periods, each lasting 4 weeks. The first was a SFA-enriched diet (38 % fat and 20 % SFA), which was followed by a carbohydrate (CHO)-rich diet (30 % fat, apoE2carriers have the highest ApoE levels, whereasapoE4individuals show the lowest concentration after the SFA, CHO and MUFA diets. Women had significantly higher ApoE concentration than men only after the consumption of the SFA diet. The SFA diet increased the ApoE plasma concentration when compared with the CHO- and MUFA-rich diets in women, but not in men. In women, but not in men, the shift from the SFA- to CHO- or MUFA-rich diets significantly decreased the ApoE concentration in apoE3/2 and apoE3/3 subjects, whereas no differences were observed in women with the apoE4/3 genotype. Sex andapoEgenotype determine ApoE plasma levels; however, this effect is dependent on dietary fat.

Background There is a reluctance to use cardiac troponins (cTn) for the monitoring of acute coronary syndrome (ACS) in hemodialysis (HD) patients because renal failure per se is thought to lead to increased cTn levels. The aim of this study was to analyse the proportion of patients with increased cTn levels in HD patients without ACS. Methods cTnI was measured with the AccuTnI ™ from Beckman (cTnI-B) and Troponin I Stat ™ from Dade Behring (cTnI-DB) assays; cTnT was measured with the third generation assay from Roche. The study included 105 HD patients. The clinical outcomes were determined after 2.5 years. Results Considering the receiver operator characteristic (ROC) cutoff, the proportion of patients with elevated cTnI-B, cTnI-DB and cTnT levels was respectively 2%, 3% and 27%. The proportion of patients with abnormal cTn values increased when a lower cutoff value was considered, based on the 99th percentile of a reference population with a coefficient of variation of less than 10% (99th percentile–10% CV cutoff). The proportion of patients with elevated values did not differ before and after the HD session. The 2.5 years mortality was associated with increased levels of cTnT but not with increased levels of cTnI. Conclusions When the ROC cutoff is applied, cTnI assays are suitable for the monitoring of ACS in HD patients. cTnT could lead to false positive diagnosis of myocardial infarction, however it is predictive of long-term mortality. The 99th percentile–10% CV cutoff does not seem appropriate in HD patients.

The 4,6-bis[2′(diethylamino)ethoxy]2,8,10-trimethylpyrido[3,2-g]quinoline (BG 637) is one of the compound from the pyrido[3,2-g] quinolines family. This compound had in vitro activity against the resistant cells and can reverse the multidrug resistance developed during the chemotherapeutic treatments.

The medical commission of the International Olympic Committee forbids the use of anabolic androgenic steroids to improve sporting performances. Nine anabolic steroids (androsterone (A), nandrolone, estradiol, testosterone propionate, nandrolone-17 propionate, dydrogesterone, testosterone, epitestosterone, boldenone) and alpha-cholestane as internal standard were studied by gas chromatography coupled with mass spectrometry (GC/MS). The derivatisation reagent employed for the derivatisation of anabolic steroids was a mixture of N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA), ammonium iodide and 2-mercaptoethanol (1000:2:6, v/w/v). Trimethylsilyl (TMS) derivatives were obtained. Anabolic steroids can be derivatised into one or two forms, mainly for androsterone into A-monoTMS and A-diTMS. The aim of this study was to research the optimization conditions of the derivatisation process (maximum yield of silylation reaction) of each anabolic steroid into only one form. A two-level factorial Doelhert design was used to determine the influence of different parameters and their interactions on each compound, thanks to response surface methodology. The parameters to be optimized were the reaction time and the temperature. The interaction "temperature-reaction time" is significant and has a positive effect on the improvement of the effectiveness of the derivatisation. Considering the large amount of information, often not convergent, a global desirability function was applied for multi-responses optimization. Thus, the optimized temperature and the reaction time of silylation were 85 degrees C and 24 min, respectively. Several GC/MS analytical parameters were also studied: linearity (regression coefficient upper than 0.99 for each compound, sensibility (range of concentration 0.05-0.30 microg/ml). Confirmatory experiments were applied to check the predicted values and to validate the model. The confirmatory assay responses are relatively close to the responses predicted. We observed satisfactory resolutions by GC/MS and a run lower than 12 min.

Background Anti-Xa activity is used as a clinical guide to anticoagulation with heparin, but heparin dosing regimens for hemodialysis were established before anti-Xa assays were developed; thus, the optimal regimen for heparin dosing was not determined. The aim is to confirm the interesting characteristics of unfractionated heparin pharmacokinetics for hemodialysis anticoagulation, provide insight into the hemorrhagic risk of hemodialysis patients, and determine the dose of unfractionated heparin and its adequate mode of administration. Study Design Cross-sectional study of the pharmacokinetics of unfractionated heparin performed during and after a 4-hour midweek hemodialysis session. Setting & Participants 35 long-term hemodialysis patients at the Sainte-Marguerite Unit of the Marseille University Hospital, Marseille, France. Predictor Hemodialysis anticoagulation with continuous unfractionated heparin infusion at a dose of 50 IU/kg/session (25 IU/kg/h during the first hour, 12.5 IU/kg during the second and third hours, and stop during the last hour). Outcome & Measurements Anti-Xa activity was monitored during the 10 hours after the beginning of the hemodialysis session. Levels of 0.3 to 0.7 IU/mL are considered sufficient for anticoagulation. Pharmacokinetics was determined by using a population approach (nonlinear mixed-effects modeling). The final model and corresponding parameter values (including interindividual and residual variability) were used to simulate 1,000 replicates. Results No case of clotting was recorded. A pharmacokinetic model with 1 compartment and first-order elimination best fitted the data. Terminal half-life was 54 minutes. Median anti-Xa activities were 0.55 IU/mL at peak, 0.25 IU/mL at end of the 4-hour session, and less than 0.1 IU/mL at 90 minutes after the session. We simulated a continuous infusion of the dose of 50 IU/kg for 1, 2, 3, and 4 hours. Peak values were 1.1, 0.8, 0.6, and 0.5 IU/mL, respectively. Values at the end of the session were 0.12, 0.18, 0.3, and 0.5 IU/mL, respectively. Values became less than 0.1 IU/mL at 15, 60, 105, and 120 minutes after the session, respectively. Limitations Interindividual variability in unfractionated heparin pharmacokinetics. Conclusions Unfractionated heparin administered by means of a 3-hour continuous infusion for hemodialysis anticoagulation provided an efficient and safe effect that quickly disappeared after the end of the session.

Plant sterols (phytosterols) are known to decrease plasma cholesterol, mainly the atherogenic LDL cholesterol. In an earlier study, the thermal stability of phytosterols in vegetable oils was reported. The aim of this present work was to investigate the potential effect of cooking (30 min in boiling water), for eight plant products (broad bean, celery, cabbage, courgette, carrot, cauliflower, onion, pepper), on the free phytosterol level. Sitosterol was the most abundant sterol, followed by campesterol. After cooking, the level of total sterols was higher in all vegetables than that before cooking, if dry matter is considered. Acid hydrolysis (active for glycosylated phytosterols) yielded a higher sterol value than alkaline hydrolysis alone (active for esterified phytosterols). This indicated that studied vegetables contained appreciable amounts of steryl glycosides. Their cooking induced higher values of free phytosterols. Cooked vegetables could give better protection against cardiovascular diseases thanks to higher phytosterol levels.

The Medical Commission of the International Olympic Committee forbids the use of anabolic androgenic steroids, -agonists, stimulant and narcotic compounds to improve athletic performance. In this work, we evaluated the thermal stability of 17 compounds by the use of the DSC for their potential GC-MS analysis either under free form or under TMS derivative form. In DSC, esterified and unesterified anabolic steroids were characterized by a true melting peak, followed by a large exothermic peak at about 251–316°C due to oxidative degradation. They could be analysed by GC-MS mainly under TMS derivatives. Hydroxylated and unhydroxylated stimulant compounds (xanthines) seemed to be more stable at high temperature. As unhydroxylated xanthines were not silylated with BSTFA – TMCS, their GC analysis would be done under their free forms. TMS derivatisation of albuterol hemisulfate and codeine phosphate is preferable. In our conditions, to analyse by GC-MS all 17 doping compounds in the same GC-MS run, the optimal silylation temperature and best column initial temperature were determined at both 60°C.

Hydrolats have the same pharmacological activities as essential oils, but more attenuated, because of lower concentrations in terpenoids. GC—MS was used in the chemical composition determination of four hydrolats: lavender (linalool, linalyl acetate), thyme (p-cymene, thymol), hydrolat of rosemary batch 1 (α-pinene, 1–8 cineole, linalool, camphor, linalyl acetate), hydrolat of rosemary batch 2 (1–8 cineole, linalool traces, camphor, borneol, α-terpineol, verbenone). Centesimal composition of each terpen was obtained by internal normalisation, concentration of each terpen was obtained by the use of internal standard method.

Vitamin E and carotenoids are fat-soluble micronutrients carried by plasma lipoproteins. Their plasma concentrations are governed by several factors, some of which are genetic, but data on these genetic factors remain scarce. We hypothesized that genes involved in lipid metabolism, i.e. the genes implicated in intestinal uptake, intracellular trafficking, and the lipoprotein distribution of lipids, play a role in the plasma concentrations of these micronutrients. To verify this hypothesis, we assessed whether the plasma status of vitamin E and carotenoids is related to genes involved in lipid metabolism. Fasting plasma vitamin E (alpha- and gamma-tocopherol) and carotenoid (alpha- and beta-carotene, lutein, lycopene, beta-cryptoxanthin, and zeaxanthin) concentrations were measured in 48 males and 80 females. The following genes were genotyped [single nucleotide polymorphisms (SNP)]: apolipoprotein (apo) A-IV, apo B, apo E, lipoprotein lipase, and scavenger-receptor class B type I (SR-BI). Plasma alpha-tocopherol concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV, apo E, and SR-BI. Plasma gamma-tocopherol concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV and SR-BI. Alpha-carotene concentrations were different (P < 0.05) in subjects bearing different SNP in SR-BI. Beta-carotene concentrations were different (P < 0.05) in subjects bearing different SNP in apo B and SR-BI. Lycopene concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV and apo B. Beta-cryptoxanthin concentrations were different (P < 0.05) in subjects bearing different SNP in SR-BI. Plasma lutein and zeaxanthin concentrations did not differ in subjects bearing different SNP. Most of the differences remained significant after the plasma micronutrients were adjusted for plasma triglycerides and cholesterol. These results suggest that genes involved in lipid metabolism influence the plasma concentrations of these fat-soluble micronutrients.

Cutaneous allergy occurs mainly as a result of the use of domestic products and cosmetics. Some fragrances, present in these products, may contain compounds that are responsible for allergy (allergens). The European Council offered a Directive limiting the level of 26 allergens found in cosmetics. GC-MS technique was used to determine the retention times of 25 allergens, determine detection and quantification limits and make calibration with standard solution of each allergen in concentrations ranging from 10 to 200 mgL -1 (21 allergens) and 50 to 200 mgL -1 (4 allergens). Quantification was performed by the use of 2 internal standards (tetradecane and hexadecane). Seven oils issued from plants were studied by GC-MS. For all of them, the concentration of potential allergens was lower than their minimum detectable level. The alcoholic solution of extracts issued from different samples of oil did not demonstrate the presence of any quantifiable allergen, even when was concentrated 25 times. GC-MS could be a useful technique in the identification and, if necessary, quantification of allergen in ingredients meant to cosmetics.

In hemodialysis patients, the relationships between serum PTH and phosphorus levels and mortality are debated because both high and low turnover bone diseases increase the risk of vascular calcifications. Furthermore, the prevalence of hypoparathyroidism is increasing, and there is a fear that this state is associated with an increase in bone fractures.We performed a cross-sectional study to determine the prevalence and the causes of hypoparathyroidism (defined as basal and post-hypocalcemic-challenge serum PTH levels55 pg/mL) in 97 patients undergoing chronic hemodialysis treatment in our unit. We then prospectively observed patients with low PTH levels (55 pg/mL, n = 26) and those with hyperparathyroidism defined as a PTH levels200 pg/mL (n = 25) during eight years for all causes of mortality and bone fractures. Kaplan-Meyer survival curves were adjusted for age and sex.Hypoparathyroidism was present in 30% of our patients. The main causes of hypoparathyroidism were parathyroidectomy (77%) and aluminium and iron overload. Survival did not differ between patients with hypoparathyroidism and hyperparathyroidism and between patients with serum phosphorusor2 mmol/L. Parathyroidectomy was associated with better survival (p0.01). Similarly, incidence of bone fractures did not differ for the two groups.Parathyroidectomy is the main cause of hypoparathyroidism in hemodialysis patients and is associated with a lower mortality risk. This result suggests that a more aggressive treatment of secondary hyperparathyroidism could decrease mortality in this high-risk population.

Cholesterol constitutes the major component of most gallstones. It was identified and determined in gallstones by thermal analysis technique (DSC and TG-DTA), mainly by the use of the melting temperature (Tonset=145°C and Tmax=149°C) and by DTG peak decomposition (Tmax=364°C). Cholesterol anhydrous (ChA), which showed endothermic polymorphic peak, Tmax=40°C, without mass loss, was differentiated from cholesterol monohydrate (ChH), which showed a broad endothermic peak, Tmax=59°C, attributed to loss of water of crystallization (theoretical 4.45%). Morphological studies of gallstones were performed by optical microscopy and scanning electron microscopy (SEM). The stones consisted of a pigmented core with a variably-sized irregular central cavity, surrounded by a radially arranged deposits of plate-like ChH. The outer part of the stones showed ChA crystal arborescences. X-ray microanalysis gave a typical spectrum rich in C and O, and in some instances the presence of P, which was attributed to the presence of phospholipids. CaCO3 was easily characterized by TG with the use of DTG decomposition peak at 674°C.

The study aimed to characterize the lipid and apolipoprotein profile and the prevalence of cardiovascular risk factors in a population of urban adult women of Morocco.A total of 213 women 25-55 y old were sampled from an agricultural province of Morocco: El Jadida. The following parameters of lipid and apolipoprotein profile were measured: plasma triglycerides (TG), plasma cholesterol (TC), triglyceride-rich lipoprotein triglycerides (TRL-TG), TRL-cholesterol (TRL-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and apolipoproteins A1, B, B48, CIII and E. Waist circumference (WC), body mass index (BMI) and blood pressure (BP) were also determined.The women studied showed the following pattern: elevated TC, LDL-C levels and TC/HDL-C in 10, 19.4 and in 43.8%, respectively; low HDL-C levels in 45.3% (0.9 mmol/l) or in 95% (when the cutoff1.3 mmol/l is used), elevated TG levels in 11.8%. Elevated TRL-C (0.6 mmol/l) and TRL-TG (0.8 mmol/l) were observed in 13.4%. Obesity and hypertension were highly prevalent in 23.9 and 16.5%, respectively. Plasma triglyceride concentrations were closely correlated with plasma concentrations of TRL-TG (R = 0.86, P = 0.0001), apoB (R = 0.50, P = 0.0001) and apoCIII (R = 0.52, P = 0.0001) and moderately correlated with HDL-C levels (R = -0.3, P = 0.0001) and BMI (R = 0.4, P = 0.0001). The association between BMI and systolic blood pressure was statistically significant (R = 0.3, P = 0.0001). Obesity, BP, TRL-C, TRL-TG, TG, apoB and apoCIII increased with age.There is a high prevalence of some risk factors for cardiovascular disease including altered lipid and lipoprotein profiles in the Moroccan urban women studied, some of these risk factors are associated with age.

A high intake of tomato products is associated with a lower incidence of upper aerodigestive tract and prostate cancers. This beneficial effect might be explained by a higher intake of carotenoids such as lycopene and/or beta-carotene. Because tomato peels, usually eliminated during tomato processing, are a valuable source of these carotenoids, we designed a study to examine whether a tomato paste enriched in tomato peels (ETP, 6% peel) increases the absorption of these carotenoids compared to a classically made tomato paste (CTP). Carotenoid bioaccessibility was evaluated using an in vitro digestion model by measuring the amount of carotenoids transferred from the pastes to micelles. Carotenoid absorption by human intestinal cells (Caco-2) was evaluated after the addition of carotenoid-rich micelles (obtained from the in vitro digestion of the 2 pastes). Carotenoid bioavailability in humans was assessed by measuring chylomicron carotenoid responses in a postprandial experiment in which 8 healthy men consumed 2 meals containing either the ETP or the CTP. ETP contained 47.6 mg lycopene (58% more than CTP) and 1.75 mg beta-carotene (99% more than CTP) per 100 g of paste. In micelles, 30% more lycopene and 81% more beta-carotene were recovered after ETP than after CTP in vitro digestion. The amount of carotenoids absorbed by Caco-2 cells was 75% greater (P < or = 0.05) for lycopene and 41% greater (P < or = 0.05) for beta-carotene after the addition of micelles from ETP than from CTP. After ETP intake the chylomicron beta-carotene response was 74% greater than after CTP intake, and the lycopene response tended to be greater (34.1%, P = 0.093). Peel enrichment of tomato paste with tomato peel is an interesting option for increasing lycopene and beta-carotene intakes.

Cyclosporine A (CsA), a common immunosuppressive agent, produces hyperlipidemia and apolipoprotein profile alterations in plasma as well as neurological and psychiatric complications. In rats, 10 mg CsA/kg/d treatments for 3 wk induce alterations of the electroencephalogram, and of the blood and brain lipids. Using this model, we evaluated whether triacylglycerol (TG)- and lecithin (PC)-enriched diets, reported to decrease epileptic episodes (TG) and to improve memory, could modify the effects of CsA treatment on brain lipids and possibly change apolipoprotein (apo) E and apoJ gene expression. To evaluate this hypothesis, three groups of rats were treated for 3 wk with CsA and received a low-fat, PC, or TG diet. Three other groups were fed the above-mentioned diets and were treated with the CsA solvent. As a control, one group was fed only the low-fat diet. The CsA-mediated decreases in brain cholesterol and PC contents, under a low-fat diet, were eliminated by the TG and PC diets. These high-fat diets induced a global increase in hippocampal transcriptional activity, as revealed by elevated polyadenylated RNA levels. The apoE and apoJ mRNA levels in the cortex and hippocampus of rats receiving the solvent were not statistically different between the TG- and PC-enriched diets but showed important variations compared with the low-fat diet solvent-treated group. A differential effect between the two high-fat diets was observed in the hippocampus, resulting in a significant increase of the apoE to apoJ ratio with the PC diet. The balance between apoE and apoJ is presumed to be important in encephalopathic mechanisms, by its involvement through low levels of brain cholesterol and PC, that might be associated with mental disorders. Our results therefore suggest that diet enrichment with polyunsaturated fat might be beneficial during CsA therapy. However, if the high levels in PC used here are more beneficial on CsA peripheral side effects than similar enrichment in TG, this does not seem to be the case in the brain. Thus, lower levels in PC should be tested.

Objective: High-density lipoproteins (HDLs) have significant cardiovascular benefits by retarding the progression of atherosclerosis. One of the mechanisms is the inhibition by HDLs of the vascular cell adhesion molecule-1 (VCAM-1) expression in endothelial cells. Our objective was to test the effect on VCAM-1 expression by the human umbilical vein endothelial cells (HUVEC) of a minor HDL2 and HDL3 apolipoprotein, the anionic peptide factor (APF). The peptide has previously been found to develop some beneficial effects against atherosclerosis, i.e. by promoting the cholesterol efflux from endothelial cells. Methods: We examined the effects of two HDL apolipoproteins A-I and APF, either in presence or absence of phosphatidylcholines (PCs), or free PCs, on the expression of VCAM-1 by HUVEC. The cells were stimulated with either the tumor necrosis factor-α (TNFα, 500 pg/ml) or the calcium bound to heparin (10 µg Ca2+/ml, 50 µg heparin/ml). Results: In the presence of TNFα, only the free PCs (0.25 and 1 mM) developed an inhibitory effect (up to 50%). In the absence of TNFα and in the presence of calcium bound to heparin, either the lipid-free APF (3.5 µM) or the APF/PC complexes (1:57 molar ratio) or the free PCs (0.25 mM) exhibited a substantial inhibitory effect (72, 71 and 42%, respectively). Conclusion: Our present findings suggest for the first time that one of the mechanisms of the antiatherogenic action of APF involves the inhibition of VCAM-1 expression by HUVEC. The peptide, through its phospholipid-binding and its calcium antagonist abilities, appears to confer on the HDLs a protective effect against the early cellular event of the inflammatory process.

The antifungal effect of the essential oil from Satureja montana L., Lavandula angustifolia Mill., Lavandula hybrida Reverchon, Syzygium aromaticum (L.) Merril and Perry, Origanum vulgare L., Rosmarinus officinalis L. and six chemotypes of Thymus vulgaris L. on Candida albicans growth were studied. The most efficiency was obtained with the essential oil from Thymus vulgaris thymol chemotype (MIC 80% = 0.016 microL/mL and Kaff = 296 microL/mL). The presence in the culture medium of essential oil from Thymus vulgaris thymol chemotype (0.01, 0.1, 0.2, 0.3 microg/mL) and amphotericin B involved a decrease of the MIC 80% of amphotericin B. In contrast, the combination of amphotericin B and low concentrations (0.00031-0.0025 microg/mL) of essential oil was antagonistic. The strongest decrease (48%) of the MIC 80% was obtained with medium containing 0.2 microL/mL of essential oil. These results signify that the essential oil of Thymus vulgaris thymol chemotype potentiates the antifungal action of amphotericin B suggesting a possible utilization of this essential oil in addition to antifungal drugs for the treatment of mycoses.

An assay was developed to quantify norepinephrine (NE) and its metabolites (MHPG and DHPG) by high-performance liquid chromatography with electrochemical detection method (HPLC-ECD) in brain tissue and plasma of rats treated by LiCl. Separation on C(18) column was obtained by a mobile phase consisting of 4.5% methanol in buffer (0.1 M sodium acetate, 0.2 M citric acid) containing 0.2 mM ethylenediaminetetraacetic acid disodium salt (EDTA Na(2)) and 0.4 mM sodium octylsulfate, operated at a flow rate of 0.8 ml/min. A potential of +0.78 V was applied across the working and reference electrodes of the detector. The precision was in the range 2.88-4.35% for NE, 5.94-11.0% for MHPG and 1.97-4.40% for DHPG. Accuracy was 98.8-99.3% for NE, 97.4-100% for MHPG and 96.1-101% for DHPG. The limit of detection was 0.6 ng/ml for NE, 0.5 ng/ml for MHPG and 0.2 ng/ml for DHPG. The linearity is over the range 20-60 ng/ml for NE, 7-23 ng/ml for MHPG and 6-20 ng/ml for DHPG. The assay has been applied successfully to measure simultaneously cortex and plasmas concentrations of these three catecholamines in rats.

Thyme (Thymus vulgaris) has been known, long time ago, for its aromatic properties. It contains essential oils and polymers such as cellulose (mixture of hemicellulose and cellulose) and lignin. The thyme, studied in this work, was gathered from the same place, in the period from November 1999 to October 2000. The chemical analysis (water, total ash, essential oils, extractive substances, cellulose, holocellulose and lignin) can be used roughly in the characterisation of the four periods that correspond to the four seasons of the year. The cellulose level was found to be more than lignin level in the wet periods (growth of the plant). The opposite was found in the dry periods. The total ash and essential oil levels were found to be high during the period of high pluviometry. The thermal decomposition of cellulose and holocellulose was found to fit well with the first-order kinetics. The activation energy, under air flow, was 185 and 196 kJ mol−1 for cellulose and holocellulose, respectively. The maximum decomposition rate and thermal analysis heating rate of lignin were found to have a direct linear relationship.

Cyclosporine-A, an immunosuppressive agent, is known to produce complications such as seizures and encephalopathies. It alters peripheral lipid metabolism, but its effect on brain lipid metabolism is unknown. Alterations in brain cholesterol and phosphatidylcholine levels, as well as in apolipoproteine E and J gene expression, are reportedly involved in epilepsy and Alzheimer's disease (AD) and were here evaluated in rats following administration of cyclosporine-A for 3 weeks. Unesterified cholesterol and phospholipid brain levels were decreased by cyclosporine whereas apolipoprotein E and J mRNA levels were not altered in hippocampus or in cortex. These alterations in brain lipid metabolism are not similar to that reported in epilepsy or AD and exclude the involvement of apolipoprotein E and J over-expression in cyclosporine-mediated neurological disorders.

Cholesterol constitutes the major component of most gallstones. It was identified and determined, in gallstones, issued from eleven patients, by thermal analysis: differential scanning calorimetry (DSC), with the use of the melting temperature and enthalpy, thermogravimetry (TG), with the mass loss of water. Anhydrous cholesterol (ChA) was characterized by two endothermic peaks (polymorphic, melting) and cholesterol monohydrate (ChH) by two endothermic peaks (dehydration, melting), too. Cha needle and Chh plate crystals were observed under polarizing light microscopy. The numerous stones obtained from nine patients were cholesterol stones: the ChA was higher 45 and lower 96%. ChH was present in stones of three patients.

The human urinary calculi are mainly constituted by calcium oxalate, magnesium ammonium phosphate hexahydrate, and uric acid. The ions or molecules are easily characterized by wet chemical methods. The difficulties appear in the differentiation of the hydrates of calcium oxalate (monohydrate COM or Whewellite, and dihydrate COD or Weddelite). A high level of COD in the urinary stones leads, often, inflammation, sharp pain and blood in urine. In the worse cases, they must be extracted by surgical way. The identification of the main components of urinary calculi, the knowledge of the true number of water molecules bounded to the calcium oxalate, and the determination of each hydrate in the mixture, are the interests of this memory. The thermal analysis (simultaneous DTA-TG) was applied on thirty-three urinary calculi. The determination of the calcium oxalate hydrates was confirmed by calorimetry (DSC).

The role of postprandial insulin in the regulation of postprandial lipid metabolism is still poorly understood. The roles of hyperinsulinemia and insulin resistance in the alteration of postprandial lipid metabolism are not clear either. To improve knowledge in this area, we submitted healthy men to acute hyperinsulinemia in two different ways. In the first study, we compared in 10 men the effects of four isolipidic test meals that induce different degrees of hyperinsulinemia on postprandial lipid metabolism. Three different carbohydrate sources were compared according to their glycemic indexes (GIs; 35, 75, and 100 for white kidney bean, spaghetti, and white bread test meals, respectively); the fourth test meal did not contain any carbohydrates. Postprandial plasma insulin levels were proportional to the GIs (maximal plasma insulin concentrations: 113 +/- 16 to 266 +/- 36 pmol/l). We found a strong positive correlation during the 6-h postprandial period between apolipoprotein (apo) B-48 plasma concentration and insulin plasma concentration (r2 = 0.70; P = 0.0001). In a second study, 5 of the 10 subjects again ingested the carbohydrate-free meal, but during a 3-h hyperinsulinemic- (550 +/- 145 pmol/l plasma insulin) euglycemic (5.5 +/- 0.8 mmol/l plasma glucose) clamp. A biphasic response was observed with markedly reduced levels of plasma apoB-48 during insulin infusion, followed by a late accumulation of plasma apoB-48 and triglycerides. Overall, the data obtained showed that portal and peripheral hyperinsulinism delays and exacerbates postprandial accumulation of intestinally derived chylomicrons in plasma and thus is involved in the regulation of apoB-48-triglyceride-rich lipoprotein metabolism, in the absence of insulin-resistance syndrome.

The aim of this work was to study the cholesterol-lowering mechanisms induced by dietary soybean lecithin in hypercholesterolemic rabbits. Male New Zealand white rabbits (n 5 6 in each group) were fed for 10 weeks either a low-fat control C diet, containing 27 g fat/kg, or high-fat diets enriched with 2 g cholesterol/kg and 77 g fat/kg. The high-fat diets contained 50 g lard (L), 50 g soybean triacylglycerol (SO), or 50 g pure soybean phosphatidylcholine (PLE). PLE diet decreased by 30% b -VLDL-cholesterol, compared with SO diet. HDL 2 -, HDL 3 - and LDL-lipid contents were unchanged in the L, SO and PLE groups. In gallbladder bile, amounts of phospholipids, bile salts and cholesterol were significantly increased in PLE group by respectively 45%, 11% and 44%, in comparison with SO group. Intestinal and hepatic Hydroxy Methyl Glutaryl Coenzyme A reductase activities were not increased by PLE diet. Triacylglycerol hepatic content was lower in PLE group than in L or SO groups. Compared with triacylglycerol enriched diet, phosphatidylcholine enriched diet developed significant higher cholesterol- and triacylglycerol-lowering effects by a two-step mechanism: i) by reducing the b -VLDLs, ii) by enhancing the secretion of bile cholesterol. Such results constitute promising effects of soybean phosphatidylcholine at the hepato-biliary level, in the treatment or prevention of hyperlipidemia and related atherosclerosis. © 2000 Elsevier Science Inc. All rights reserved.

Background: Apolipoprotein B-48 (apoB-48) is produced by the small intestine, as part of chylomicrons, and appears to be a suitable marker for clinical studies of postprandial lipoproteins and related cardiovascular risk. Our aim was to develop, for routine analysis, an assay to quantify apoB-48 in plasma samples.Methods: A microtiter plate was coated with a C-terminal apoB-48-specific heptapeptide. Plasma samples were incubated with appropriate detergent to allow competition between immobilized antigen and plasma apoB-48. Appropriate calibration curves were obtained in the ELISA, using calibrated lymph and chylomicrons.Results: Treatment of plasma samples with the mild detergent Triton X-100 allowed an efficient competition between immobilized antigen and plasma apoB-48. No cross-reactivity was found with apoB-100, as checked by ELISA and Western blot analysis. Intra- and interassay CVs were 5.4% and 5.5%, respectively. In healthy subjects, apoB-48 concentrations markedly increased in the postprandial state, in parallel with triglycerides.Conclusions: This new ELISA allows determination of the concentration of apoB-48 in normolipidemic plasma.

We know that upper body obesity is associated with metabolic complications, but we don't know how regional body fat distribution influences postprandial lipemia in obese adults. Thus, this study explored the respective effects of android or gynoid types of obesity and fasting triglyceridemia on postprandial lipid metabolism and especially triglyceride-rich lipoproteins. Twenty-four obese and 6 lean normotriglyceridemic women (control), age 24-57 yr, were enrolled. Among obese women with an android phenotype, 9 exhibited normal plasma triglyceride levels (mean: 1.38 mmol/L) (NTAO), and 7 displayed a frank hypertriglyceridemia (mean: 2.40 mmol/L) (HTAO). The 8 patients with a gynoid phenotype had normal triglyceride levels (mean: 1.00 mmol/L) (GO). All were given a mixed test meal providing 40 g triglycerides. Serum and incremental chylomicron triglycerides 0-7 h areas under the curve (AUCs) as well as triglyceride levels in apoB-48-containing triglyceride-rich lipoprotein (TRLs) or chylomicrons were significantly higher in HTAOs and NTAOs than in GOs and controls postprandially. The size of chylomicron particles was bigger in controls and GOs than in HTAOs and NTAOs postprandially. Android obese subjects showed abnormally elevated fasting apoB-48 and apoB-100 triglyceride-rich lipoprotein (TRL) levels. Most abnormalities that were found correlated to plasma levels of insulin and apoC-III. In conclusion, an abnormal postprandial lipid pattern is a trait of abdominal obesity even without fasting hypertriglyceridemia.

We hypothesized that intestinal absorption and postprandial re-secretion of dietary cholesterol may be a particularly complex process in humans. To test this hypothesis, we used deuterium-enriched cholesterol to specifically label meal cholesterol and developed an improved method for quantitative measurement of traces of deuterated cholesterol as well as cholesterol with reference to two different internal standards by gas chromatography–mass spectrometry (GC–MS) measurement. In the first study, a group of healthy subjects ingested a single test meal containing deuterated cholesterol with a 7 h postprandial follow-up. In the second one, a group of healthy subjects ingested a first test meal containing deuterated cholesterol and a follow-up was performed during three consecutive test meals and later until 72 h. The most striking observations were that the occurrence of dietary cholesterol in chylomicrons is not concomitant to triglycerides and is very low after a single meal while most dietary cholesterol is re-secreted in chylomicrons after a second, and even a third, fat test meal. The data obtained show that the re-secretion of dietary cholesterol from the small intestine is a slow and complex process in humans.

The aim of this work was to assess, the effect of a dietary supplement of soyabean lecithin on the apoprotein (apo) AI–high density lipoprotein system in humans. Adult outpatients (three women and seven men, aged 52 ± 5 years) were selected on the basis of a major type IIA hypercholesterolemia (>6.5 mmol/L). For each subject, a previous control period of 6 weeks consisted in a daily dietary supplement of 3 g soyabean oil (SO) as placebo distributed in two capsules at three main meals. Subjects then were given a daily dietary supplement of 3 g purified soyabean phosphatidylcholine (SPC) for 6 weeks, also distributed in two capsules at the three main meals. The usual basal diet of each subject was monitored every 4 weeks by a 3-day food recall. Between the end of the SO period and the end of the SPC period, plasma level of apo AI significantly increased (from 1.01 to 1.23 g/L), as did unesterified cholesterol (from 1.80 to 2.00 mmol/L). The esterified cholesterol to total cholesterol ratio and apo E level significantly decreased between the beginning and the end of the experiment. Esterified cholesterol and apo B levels remained unchanged. The levels of apo AI or unesterified cholesterol were not correlated to the alcoholic calories or to total or lipid energy. Dietary soyabean lecithin contributed to stimulation of the reverse cholesterol transport by increasing apo AI system and decreasing apo AII and apo E systems. Thus, soyabean lecithin could be considered an effective nutrient useful in the dietary treatment of mild hypercholesterolemia.

An assay was developed to quantify deuterated cholesterol (used as a tracer) and cholesterol using gas chromatography–mass spectrometry. Ergosterol and epicoprostanol were used as internal standards. Deuterated cholesterol was quantified by comparing its peak area to that of epicoprostanol and cholesterol to ergosterol. The mean absolute recovery in spiked serum was 99.96%; the precision was in the range 0.16–10.9% and accuracy 90.4–100%; the limit of detection in plasma was 3·10 −5 mmol l −1 . Using two internal standards, the method described herein seems particularly suitable for application in humans i.e., measuring traces of deuterated cholesterol (range: 0–6.26·10 −4 mmol l −1 ) along with natural cholesterol (range: 0.065–4.42 mmol l −1 ) in human plasma and lipid fractions postprandially.

Dans de nombreux laboratoires de biologie medicale, en particulier dans les CHU, sont mis au point des examens ne faisant pas l’objet de methodes commercialisees. Ces examens sont realises a l’aide de reactifs prepares dans le laboratoire a partir de produits de base ou de produits de « recherche » (produits chimiques, anticorps, enzymes, sondes …). Ces reactifs ne sont pas des dispositifs medicaux pour le diagnostic in vitro (DMDIV) et n’ont pas d’obligation de marquage [...]

Objectives We studied the effect of a standardized breakfast or lunch before blood sampling on 77 analytes. Design and methods The mean difference between assays from 20 healthy adults was calculated on blood samples taken before and after food intake. Significant differences were tested using two-tailed Student t-test and compared to the acceptable limits derived from analytical and intraindividual biological variation. Results Most of the analytes investigated were not significantly affected by food intake. Six of them were influenced by breakfast or lunch: triglycerides, glucose, creatinine, C-peptide and insulin were significantly upregulated, whereas testosterone was downregulated. Fourteen parameters were more influenced by time of sampling than by meals: nine decreased during the day (total bilirubin, BNP, myoglobin, cortisol, TSH, C-telopeptide, prolactin, ACTH, uric acid) and two increased (white blood cells, neutrophils). Three parameters showed levels that were similar at 9:00 am and 5:00 pm but their lowest level at 12:30 pm (inorganic phosphorus, osteocalcin, PTH). Conclusions Fasting is necessary for some laboratory tests. Clinicians should be aware of variations due to sampling time before ordering non-fasting tests, and in the subsequent interpretation of results.

The levels of 16 USEPA priority PAHs in surface sediments and four dated sediment cores from Toulon Bay were determined and characterized by strong implantation. The total PAH levels in the superficial sediments ranged from 0.30 to 34.11 mg.kg-1 dry weight in the 0-5 layer and from 0.34 to 54.68 mg.kg-1 dry weight in the 5-10 layer. The qualitative assessment of sediment samples revealed relatively high PAH levels compared with French reference values. The results indicated that the PAHs in Toulon Bay are of pyrolytic origin. Estimating the rate of sedimentation based on pronounced events, such as explosive growth in the use of petroleum products, major developments, and periods of conflict, can be used to follow the history of pollution based on its composition over a period of approximately 130 to 180 years, depending on the length of the cores.

We evaluated the prognostic value of plasma N-terminal-pro-brain natriuretic peptide (NT-pro-BNP) in 71 transplanted heart recipients during a 38 +/- 2 month follow-up. The negative predictive value of NT-pro-BNP levels/=800 pg/ml to predict death was 97% (95% confidence interval 92 to 100). Thus, NT-pro-BNP levels/=800 pg/ml predict a middle-term good survival in transplanted heart recipients.

The growth hormone (GH)–insulin-like growth factor-1 (IGF-1) axis is dramatically altered in patients with anorexia nervosa (AN). The aim of the present study was to investigate whether GH and IGF-1 could be predictors of outcome in patients with a restrictive form of AN. Blood levels of GH, IGF-1, adipocytokines, ghrelin, insulin, glucose, and sex and thyroid hormones were measured in eleven women inpatients with AN and in ten healthy women controls. Three stages were compared during refeeding: admission (T0), when BMI reached 16 kg/m2 (T1) and at discharge when BMI reached 17·5 kg/m2 (T2). Clinical status was assessed 6 months after discharge from hospital (T3), and remission was defined by the maintenance of a BMI ≥ 17·5 kg/m2. AN patients in remission (AN-R; n 6) had significantly higher GH levels at admission than those who relapsed (AN-NR; n 5) (PPPr2 0·88, P

This study evaluates the possible interaction between chronic oat bran intake and the postmeal metabolic response. Six normolipidemic men consumed three different diets for 14 d, at the end of which they consumed a test meal. The diets were C (control), basal low-fiber diet (15.6 g fiber/d) and a low-fiber (2.8 g fiber) test meal; OB (oat bran), basal low-fiber diet and a 40-g oat bran-enriched test meal (12.8 g fiber); and OB-A (oat bran-adaptation), 14-d oat bran (40 g/d) supplemented diet (23.8 g fiber/d) and an oat bran test meal (12.8 g fiber). The diets were fed in a random order. Fasting and postmeal blood samples were obtained for 7 h and lipoproteins were isolated. Adding oat bran to the test meals markedly reduced the postmeal insulin rise (P < 0.05). Compared with the low-fiber control diet, the effects elicited postprandially by adding oat bran to a single meal were enhanced after 14 d of oat bran feeding, ie, increased plasma triglycerides, phospholipids, and free cholesterol; decreased plasma esterified cholesterol; increased chylomicron and small-sized triglyceride-rich lipoprotein triglycerides; increased LDL and HDL free cholesterol; and decreased HDL esterified cholesterol. Thus, chronic oat bran feeding alters the postmeal response in human subjects.