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L'alimentation peut jouer un rôle sur le nombre et le type de leucocytes présents dans la muqueuse de l'intestin grêle. Les objectifs de cette étude sont de 1) quantifier et caractériser les lymphocytes et les éosinophiles de la lamina propria ainsi que 2) d'évaluer le type de mucine sur des biopsies duodénales de chevaux soumis à différentes diètes. Une variabilité des cellules et des mucines devrait être observée en fonction de l'alimentation. Sept juments (n = 7) ont d'abord reçu une alimentation riche en fibres pendant six semaines et ensuite, une alimentation riche en protéines pendant six autres semaines. Une biopsie endoscopique duodénale a été effectuée à la fin de chaque période de diète. Une coloration à l’hématoxyline-éosine-phloxine-safran, une immunohistochimie pour quantifier les lymphocytes T (CD3) et B (CD20) ainsi qu’une coloration AB PAS pour étudier les mucines ont été effectuées. Un compte des lymphocytes identifiés à l’hématoxyline-éosine-phloxine-safran, au CD3 et au CD20 ainsi que des éosinophiles identifiés à l’hématoxyline-éosine-phloxine-safran a été fait. Les mucines ont été évaluées qualitativement. Pour 11 des 13 biopsies, le compte de lymphocytes totaux était plus élevé lorsqu'ils étaient identifiés avec l'immunohistochimie que lorsqu'ils étaient identifiés avec l'hématoxyline-éosine-phloxine-safran (p = 0,057). Les juments, lorsqu’elles sont nourries avec une diète riche en protéines, présentent un ratio lymphocytes T/lymphocytes B qui augmente significativement (p = 0,026). Les éosinophiles et les mucines ne sont pas modifiés par ces deux diètes. Pour conclure, l’immunohistochimie est nécessaire pour démontrer l'impact de l’alimentation sur le ratio lymphocytes T/lymphocytes B de la lamina propria des biopsies duodénales de juments saines. De futures études pourront se servir de ces notions pour évaluer les facteurs de variation des leucocytes duodénaux dans le but d’établir des valeurs de références de ces cellules pour la muqueuse intestinale normale., Diet may play a role on the number and type of small intestinal mucosal leucocytes. The objectives of this study are 1) to quantify lymphocytes and eosinophils of the lamina propria and, 2) to evaluate the type of mucins present in duodenal biopsies from horses fed different diets. A variability in leukocytes and mucins should be observed with the diet change. Seven mares (n = 7) were fed for six weeks a diet rich in fibers followed by another six weeks of a diet rich in proteins. One endoscopic duodenal biopsy per horse was taken at the end of each period of diet. An hematoxylin-eosin-phloxin-saffron stain, an immunochemistry to evaluate T lymphocytes (CD3) and B lymphocytes (CD20) and an AB PAS stain to evaluate mucins were performed. A quantification of lymphocytes identified by hematoxylin-eosin-phloxin-saffron, CD3 and CD20 and of eosinophils by hematoxylin-eosin-phloxin-saffron was performed. Mucins were qualitatively evaluated. For 11/13 biopsies the lymphocyte count was higher when identified with immunochemistry than identified by hematoxylin-eosin-phloxin-saffron stain. Mares, when fed a protein rich diet, have a significantly higher ratio of lymphocytes T/lymphocytes B (p = 0,026). No differences were found for eosinophils and mucins with the diet change. These results indicate that immunochemistry is necessary to identify the impact of the diet on the lymphocytes T/lymphocytes B ratio of the lamina propria in duodenal biopsies from healthy mares. The results from this study can be used to evaluate factors contributing to duodenal leukocytes variation to establish reference values for the range of the number of leukocytes found in the normal equine intestinal mucosa.

Western blot and immunohistochemistry are two routine clinical techniques to characterize the expression of dystrophin in patients with dystrophinopathy. Discrepancies may exist. Some patients may have weakly positive immunohistochemical staining, of non-reverting appearance (traces), contrasting with negative Western blot results. The clinical impact of this residual dystrophin is questionable. To better characterize and determine if this weak expression can mitigate disease severity, we focused on patients with null dystrophin on Western blot. Residual dystrophin expression on immunohistochemistry was correlated with age at loss of ambulation of patients included. Clinical data were obtained from medical care centres. Time-to-event analysis was performed for age of loss-of-ambulation. The patients included were from a previous study and none had dystrophin on Western blot (n=42). Patients with trace of dystrophin on immunohistochemistry, despite the absence of dystrophin on Western blots, ambulated longer than patients without dystrophin or with 40 isolated revertant fibers (HR 0.05; 95% CI 0.00-0.53; P=0.013). These results were obtained with antibodies specific to the terminal carboxy domain of dystrophin. These results were not confirmed for those targeting the central domain. In conclusion, any dystrophin in immunohistochemistry seems useful in reducing the severity of the phenotype. On the other hand, dystrophin expressed must include the functional sites necessary for its action. Our results must be interpreted in light of the limitations inherent in the methodology of our study.; Le Western blot et l’immunohistochimie sont deux techniques de routine clinique pour caractériser la dystrophine exprimée de patients avec dystrophinopathie. Des discordances peuvent exister. Certains patients peuvent avoir un marquage immunohistochimique faiblement positif, d’aspect non révertant (traces), contrastant avec des résultats négatifs en Western blot. L’impact clinique de cette dystrophine résiduelle pose question. Pour mieux caractériser et déterminer si cette expression faible peut atténuer la sévérité de la pathologie, nous nous sommes intéressés à des patients sans dystrophine en Western blot. Nous avons comparé les âges de perte de marche en fonction des quantités de dystrophine retrouvées en immunohistochimie. Les données cliniques sont issues des dossiers médicaux de leurs centres respectifs. Des analyses de survie ont été réalisées pour les âges de perte de marche. Les patients inclus sont issus d’une précédente étude et aucun n’avait de dystrophine en Western blot (n=42). Parmi ces patients, ceux avec trace de dystrophine en immunohistochimie étaient ambulants plus longtemps que ceux avec dystrophine nulle ou uniquement révertante (HR 0,05 ; IC95% 0,00-0,53 ; P=0,013). Ces résultats ont été obtenus avec des anticorps spécifiques du domaine carboxy terminal de la dystrophine. Ces résultats n’ont pas été confirmés pour ceux ciblant le domaine central. En conclusion, toute dystrophine en immunohistochimie semble utile à l’atténuation de la sévérité du phénotype. Celle-ci doit en revanche comporter les sites fonctionnels nécessaires à son action. Nos résultats doivent être interprétés à la lumière des limites inhérentes à la méthodologie de notre étude.

International audience; Fever is a frequent reason for consultation in pediatric emergency departments and raises the question of biological and radiological examinations. Rapidly obtaining the result of C-reactive protein (CRP) level is essential in front of the steady increase of the number of visits. We carried out a prospective study within the pediatric emergency department of the University Hospital of Clermont-Ferrand from January to April 2017, in order to evaluate the interest of the capillary CRP in point of care (POCT). In two periods, 68 patients (28 controls without and 40 cases with capillary CRP assayed on a Afinion® AS100) with naked fever greater than 48 hours were included. After a study of the analytical performances of Afinion® and a verification of the homogeneity and the comparability of the two groups on clinical criteria (age, sex, duration of the fever, antibiotics treatment) and biological (values of CRP), the interest of the CRP in POCT was evaluated. In the POCT group, a significant drop in the median of the emergency room consultation time (60 (IQR 33-125) versus 180 (IQR 158-208) minutes), the number of biological acts by patient (1 (IQR 1-3) versus 7 (IQR 3-8)), the global cost of biological and radiological examinations per patient (5.4 (IQR 5.4-32.6) versus 153.8 (IQR 46.9-180.4) euros), and the cost of reagents spent by the laboratory per patient (5.2 (IQR 5.2-6.4) versus 33.2 (IQR 2.3-34.2) euros). Thus, in the context of a clinical-biological partnership, the use of CRP in POCT present a practical and an economic interest.

International audience; INTRODUCTION: Phenotype changes between primary tumor and the corresponding brain metastases are recent reported data. Breast cancer, with biological markers predicting prognosis and guiding therapeutic strategy remains an interesting model to observe and evaluate theses changes. The objective of our study was to compare molecular features (estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor type 2, [HER2]) between brain metastases and its primary tumor in patients presenting with pathologically confirmed breast cancer.MATERIAL AND METHODS: This retrospective study was based on the immunohistochemical analysis of the brain metastases paraffin embedded samples stored in our institutional tumor bank, after surgical resection. The level of expression of hormonal receptors and HER2 on brain metastases were centrally reviewed and compared to the expression status in primary breast cancer from medical records.RESULTS: Forty-four samples of brain metastases were available for analysis. Hormonal receptor modification status was observed in 11/44 brain metastases (25%) for ER and 6/44 (13.6%) for PR. A modification of HER2 overexpression was observed in brain metastases in 6/44 (13.6%). Molecular subtype modification was shown in 17 cases (38.6%). A significant difference was demonstrated between time to develop brain metastases in cases without status modification (HER2, ER and PR) (med=49.5months [7.8-236.4]) and in cases in which brain metastases status differs from primary tumor (med=27.5months [0-197.3]), (P=0.0244, IC95=3.09-51.62, Mann and Whitney test).CONCLUSION: the main interest of this study was to focus on the molecular feature changes between primary tumor and their brain metastases. Time to develop brain metastases was correlated to phenotypic changes in brain metastases.; Introduction:La modification phénotypique entre une tumeur primitive et sa métastase cérébrale correspondante est une donnée récente. Le cancer du sein, de part ses biomarqueurs impactant le pronostic et la stratégie thérapeutique, constitue une pathologie d’intérêt pour observer et évaluer ce type de modification. L’objectif était de comparer les caractéristiques moléculaires (récepteurs aux estrogènes [RE], à la progestérone [PR], et récepteur au facteur de croissance épidermique humain type 2 [HER2]) des métastases cérébrales et des tumeurs primitives correspondantes de patients porteurs d’un adénocarcinome mammaire.Matériels et méthodes:Cette étude rétrospective, utilisait des échantillons tumoraux issus des métastases cérébrales réséquées, inclus en paraffine, conservés en tumorothèque. Le niveau d’expression des récepteurs hormonaux et de HER2, sur chaque couple primitif/métastase cérébrale correspondante était analysé par immunohistochimie.Résultats:Quarante-quatre échantillons de métastases cérébrales étaient exploitables. La conversion des récepteurs hormonaux a été observée pour 11/44 métastases cérébrales (25 %) pour RE et pour 6/44 cas (13,6 %) pour RP. L’expression de HER2 était modifiée au sein de la métastase cérébrale dans 6/44 cas (13,6 %). Le changement de sous-type moléculaire était montré dans 17 cas (38,6 %). Il existait une différence significative pour le délai de survenue de la métastase cérébrale entre le groupe ne présentant pas de modification pour RE, RP ou HER2, (med = 49,5 mois [7,8–236,4]) et le groupe dont le phénotype de la métastase cérébrale différait du primitif (med = 27,5 [0–197,3]), (p = 0,0244, IC95 = 3,09–51,62, test de Mann et Whitney).Conclusion:L’intérêt de ce travail était la mise en évidence de modification de signature moléculaire entre la tumeur primitive et la métastase cérébrale correspondante. Le délai de survenue de la métastase cérébrale apparaissait corrélé à la modification de statut phénotypique de la métastase cérébrale.

Immunoassays are used daily by clinical endocrinologists to refute or confirm a diagnosis, or to follow up the course of a treatment. Immunoassays have become increasingly sensitive, specific and reproducible, so that clinicians have great confidence in their results. However, they do not always yield correct results because interferences still occur. In the first part of this review, immunoassay interferences are described and their mechanisms explained: matrix effects, specificity defaults, interferences from antibodies and binding proteins, or the hook effect. The hormones most frequently concerned by these pitfalls are reviewed, even as strategies used to prevent and minimize interferences. In the second part, the consequences of failure to recognize an interference are reviewed: unjustified clinical decisions (wrong diagnosis, treatment, surgery) and, more exceptionally, publication in the scientific literature of erroneous results. Clinicians may sometimes inform laboratories of an increased risk of interference. In general, clinicians are in the best position to fully validate test results; because only they know all the medical data about their patients. If there is any suspicion of discrepancy between clinical and laboratory data, they must alert the laboratory. This is the only way to better detect and, if possible, eliminate interferences and their regrettable outcomes.

A permanent and quantitatively abnormal proteinuria (150 mg/ 24 h) found at the laboratory should be followed by an identification and quantification of all proteins present. Specific immunochemistry techniques (immunoturbidimetric or immuno-nephelometric) are almost exclusively used for measuring albumin (or microalbuminuria) in nephropathic diabetic patients. Measurement of monoclonal free light chains is not recommended due to poor accuracy. Determination of other small proteins (molecular mass, MM40 kDa), transferrine, immunoglobulins G (assessment of selectivity) is far less frequent and Tamm-Horsfall protein is measured in specialized laboratories. Global electrophoresis techniques are the reference methods for the study of urinary proteins. Significant progress have been made during the past ten years in terms of sensitivity (analysis down to 50 mg/L total protein with no need to concentrate urinary specimens) and separation (high resolution or according to MM). Improvement in sensitivity is a key point for the diagnostic and follow-up of low grade or treated gammapathies. Electrophoretic separation according to MM is perfectly adapted to visual typing of renal proteinuria (glomerular, tubular or mixed) and overload proteinuria, particularly by monoclonal free light chains (MM: 25 kDa, Bence Jones proteinuria) allowing their quantification by densitometry. Immunofixation combining electrophoresis and immunoprecipitation in gel has emerged as the reference technique to identify monoclonal proteins. Data obtained by urinary protein analysis need to be compared with serum results for interpretation.

The aim of this study was to compare, with manufacturer's agreement, twelve direct and non-isotopic commercial assays of progesterone. We have evaluated the analytical performances: low limit detection, imprecision, accuracy (recovery and dilution tests) and we have tested some patient samples. Results were compared to a reference method using isotope dilution Gas Chromatography and Mass Spectrometry combination (GC-MS). For each assay, analytical qualities and defaults are established. Large differences are found between progesterone concentration measured on the same sample with the different methods essentially for the low concentrations. Comparison with GC-MS raised questions about the accuracy of the different assays. This work will be aid laboratories to their choice and/or validation.

Stimulated by epidemic outbreaks in years 80's and 90's detection methods for Listeria, and L. monocytogenes particularly, have undergone many important progresses. New selective media for isolation and enrichment have been formulated with the aim to improve bacteriological methods and decrease time delays. For identification of Listeria at the species level, some biochemical miniaturised tests allow response within 24 h. Within the immuno-chemical methods as ELISA or ELFA, the revelation step has been shortened and automated. The elaboration of L. monocytogenes specific antibodies begins to upset immunological methods. As far as concern simplification of detection tests, a new generation of small immunological plate-shaped tests has been marketed. Whatever the immunological method considered, intrinsic sensibility is about 10(5) at 10(6) CFU/ml. Only one method allows more sensibility: the immuno-magnetic separation. With a sensibility of 1 CFU/ml, immunocapture allows shortening of enrichment time of 24 h or eliminates this step altogether if the aim is to count the Listeria directly in the sample. In the biological molecular methods, some hybridization tests with nuclear probes allow rapid and specific detection of L. monocytogenes. The polymerase chain reaction has been improved to simplify and shorten the DNA preparation and the revelation of amplified fragments. This method will be soon used in food samples analysis. The elaboration of new methods that could allow the specific detection of L. monocytogenes pathogenic strains of is one of future stake.

Since the introduction of fully automated nephelometric systems simultaneous measurements of immunoglobulin light chains kappa (kappa) and lambda (lambda) and IgG, IgA and IgM have become increasingly used for the routine assessment of humoral immunity. From these data two ratios were calculated, the kappa/lambda ratio and the heavy chains to light chains ratio. As changes in these ratios might have some predictive clinical value besides reflecting a monoclonal component, it is necessary to know mean and reference limits of these ratios. On account of differences in the calibration method of the light chains measurements (either free light chains or light chains bound to a complete molecule) and of differences in the calculation method of the heavy chains to light chains ratio we were led to conduct our own investigation. IgG, IgA and IgM and kappa and lambda light chains were immunonephelometrically measured in the sera of 84 blood donors. For each sample theoretical values for kappa + lambda, kappa and lambda, and kappa/lambda were calculated using the existing relation between the concentration of a given immunoglobulin and the concentration of bound light chains. Using the Valtec Protocole and the t test we were able to evidence highly significant differences (p10(-4) between theoretical and experimental values of kappa, lambda and kappa + lambda; those differences could be proved to be directly linked to the nephelometric technique itself. However the experimental kappa/lambda ratio did not appear to differ from the theoretical one nor the standardization method to have an effect on the reference values of this ratio, our values (mean and reference limits, 1.81, 1.29-2.53) being very similar to previously published results. Concerning the so called heavy chains to light chains ratio two methods were used to express it, one consisting in the ratio of the theoretical kappa + lambda value to the experimental one with the following results, 1.05 and 0.93-1.18 for the mean and reference limits and the other one using the raw data. The results were as follows: mean 3.50, reference limits 3.11-3.94.

Mycoplasma pneumoniae (MP) infection is associated with the emergence of anti-I cold agglutinins of IgM isotype, rarely complicated by hemolytic anemia. The mechanism by which the autoimmune disease occurs is still considerably controversed. We describe here a case of MP infection complicated by severe autoimmune hemolytic anemia with monoclonal anti-I IgM. IgM anti-I antibodies were purified by adsorption-elution on OI+ red cells. The red blood cell antibodies were found to be tightly associated with IgG and anti-MP specificity probably as immune complexes. The significance of these results is discussed.

The purpose of this study which was carried out in the Central African Republic between January and February 1994 was to evaluate the effectiveness of the Parasight F test in diagnosing malaria in the indigenous population. Comparison of test results in a series of 62 malaria suspects who had been residing in the country for more than 10 years and 67 malaria suspects who had been living abroad showed significant differences but the overall value of the test was satisfactory. The test was specific for Plasmodium falciparum. In-field trials showed that the test could be used effectively by paramedics and community health care workers. Basing the decision to perform antimalarial treatment in semi-immune subjects with suspected malarial solely on the results of the Parasight F test would have led to unwarranted non-treatment in 10% of cases. Presumptive treatment of malaria is justified. The Parasight F test allows identification of Plasmodium falciparum and adaptation of therapy if required by the spread of chemoresistance.

The analysis methods for the detection and quantitation of foreign proteins in meat products are reviewed: indirect determinations, physico- and immunochemical procedures. Among all these available techniques, the most suitable are ELISA and electrophoresis.

The usefulness of a nephelometric-based serum myoglobin assay kit in the early diagnosis of acute myocardial infarction was assessed in 92 consecutive patients admitted within 24 hours of the onset of spontaneous chest pain lastingor = 20 minutes. The discharge diagnosis was acute myocardial infarction in 37 patients (40.2%), myocardial infarction lastingor = 6 hours in 10, and no myocardial infarction in 45 (48.9%). The characteristic curve showed that the best differential diagnostic value was a serum myoglobinor = 130 micrograms/l (sensitivity, 75.6%; specificity, 91.7%; positive-predictive value, 88%; negative-predictive value, 82%). The initial diagnosis was doubtful in 33 patients (36%) because of an inconclusive electrocardiogram. A serum myoglobin value ofor = 130 micrograms/l would have identified 9 of the 13 patients with acute myocardial infarction and all of the 20 patients without myocardial infarction, giving an accuracy of 84.8%. These results suggest that this new rapid, quantitative serum myoglobin assay would be useful in the evaluation of suspected myocardial infarction, especially in patients with an inconclusive electrocardiogram.

Ultrastructural and immunohistochemical analysis of six specimens revealed for the first time a small number of Langerhans cells in non-neoplastic bronchial epithelium. These cells were usually found either interspersed perpendicularly between columnar epithelial cells or just above the basal lamina with extending cytoplasmic processes. Usually few Birbeck granules, especially located in the Golgi region, were present throughout the cytoplasm. Immunohistochemical studies were performed on semi-thin sections with a polyclonal anti-S-100 protein. The population of S-100 positive cells represented about 1% of all the epithelial cells. Not all ultrastructurally identified Langerhans cells were shown to be positive for S-100 antigen. Our results suggest that Langerhans cells could be a constant cellular constituent for the normal bronchial epithelium. The exact function of Langerhans cells in the respiratory epithelium remains to be investigated, but they may have an immunologic function, such as antigen presentation to T lymphocytes.