1,721,151 research outputs found
Analysis of the risk factors of venous thromboembolic disease (VTE) in women with oestroprogestative contraception
No full textL'objectif de notre première étude était d'identifier les déterminants génétiques et environnementaux du risque de maladie thromboembolique veineuse (MTEV) chez les femmes sous contraceptifs oraux combinés (COC). Après ajustement pour les facteurs confondants, les principaux déterminants environnementaux de la MTEV étaient le tabagisme (OR = 1,65) et un indice de masse corporelle supérieur à 35 kg.m2 (OR = 3,46). En outre, la thrombophilie héréditaire sévère (OR = 2,13) et les groupes sanguins non-O (OR = 1,98). Nous avons confirmé que l’histoire familiale au premier degré de MTEV prédit mal la thrombophilie. En conclusion, cette étude confirme l'influence du tabagisme et de l'obésité et pour la première fois l'impact du groupe sanguin ABO sur le risque de MTEV chez les femmes sous COC. Elle confirme également la faible sensibilité de l'histoire familiale de MTEV pour dépister les thrombophilies héréditaires.Le but de la deuxième étude était d'étudier, chez les utilisatrices de COC, l'impact des polymorphismes génétiques nouvellement identifiés par les études pangénomiques associés au risque de MTEV dans la population générale. Neuf polymorphismes situés sur les gènes KNG1, F11, F5, F2, PROCR, FGG, TSPAN15 et SLC44A2 ont été génotypés dans un échantillon de 766 cas et 464 témoins dans le cadre de l’étude PILGRIM. Seul le polymorphisme rs2289252 situé sur le F11 était significativement associé au risque de MTEV. La présence de l’allèle rs2289252-A du F11 était associée à un risque accru de MTEV (OR =1,6). En outre, la combinaison de l’allèle rs2289252-A et du groupe sanguin non-O, était associée à un risque d’OR de 4.The aim of our first study was to identify the genetic and environmental determinants of venous thromboembolism (VTE) risk in a large sample of women using combined oral contraceptives (COC). A total of 968 women with a personal history of VTE during COC use were compared with 874 women under COC, but no personal history of VTE. After adjustment for confounding factors, the main environmental determinants of VTE were smoking odds ratio (OR = 1.65) and a body mass index greater than 35 kg.m-2 (OR = 3.46). In addition, severe hereditary thrombophilia (OR = 2.13) and non-O blood groups (OR = 1.98) have been shown to be important genetic risk factors for VTE under COC. First-degree family history of VTE predicts thrombophilia poorly. In conclusion, this study confirms the influence of smoking and obesity and for the first time the impact of ABO blood group on the risk of VTE in women under COC It also confirms the low sensitivity of the family history of VTE to detect hereditary thrombophilia. The purpose of the second study was to study, in COC users, the impact of newly identified genetic polymorphisms by genome-wide as associated with the risk of VTE in the general population. Nine polymorphisms on the KNG1, F11, F5, F2, PROCR, FGG, TSPAN15 and SLC44A2 genes were genotyped in a sample of 766 patients and 464 controls in the PILGRIM study. Only the rs2289252 polymorphism on the F11 was significantly associated with the risk of VTE. The presence of the F11 rs2289252-A allele was associated with an increased risk of VTE (OR = 1.6). In addition, the combination of the rs2289252-A allele and the non-O blood group was associated with an OR risk of 4
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Blood
No full textArterial and venous thromboses are the most significant complications in patients with myeloproliferative neoplasms (MPN), with the primary treatment goal being thrombotic risk reduction. In MPN with no history of thrombosis, primary prevention mainly involves the use of aspirin and cytoreduction is added in high-risk patients. However, thrombotic complications can unveil an MPN in approximately 20% of cases, necessitating the initiation of both antithrombotic therapy for the thrombosis and cytoreductive treatment for the MPN. The duration of anticoagulant therapy following an initial venous thromboembolic event (VTE) is subject to discussion. Furthermore, the occurrence of a thrombotic complication in patients with a known diagnosis of MPN prompts a reconsideration of both antithrombotic and hematological management. This review employs case-based discussions to explore the management of thrombotic complications in MPN patients. It addresses the nature and duration of antithrombotic treatments, as well as the approach to cytoreduction. Special attention is given to the place of direct oral anticoagulants and to the management of MPN patients with splanchnic vein thrombosis, which is disproportionately common in this group
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Research of new rapid flow cytometry tests for "bedside" diagnosis : application to the discrimination between bacterial and/or viral infections in order to reduce unnecessary antibiotic use
No full textLes maladies infectieuses sont des pathologies dont le diagnostic étiologique est souvent complexe. Le clinicien doit baser son diagnostic sur ses observations cliniques et les relier aux mesures biologiques du patient. Plusieurs groupes recherchent activement de nouveaux marqueurs biologiques pour préciser ce diagnostic. C’est dans cette optique que la cytométrie en flux a été utilisée et optimisée pour comparer l’expression de nouveaux biomarqueurs sur les cellules du sang des patients infectés ou des sujets sains. La caractérisation des mécanismes d’expression des marqueurs montre que l’expression du CD64 sur les neutrophiles est amplifiée chez les patients infectés par une bactérie via l’interféron γ, alors que l’expression du CD169 sur les monocytes est amplifiée chez les patients infectés par un virus via la famille des interférons de type I (α, β, ω). De plus, l’expression de l’HLA-DR sur les monocytes semble aider à l’identification étiologique de l’infection. Les travaux suggèrent que le dosage de ces trois biomarqueurs par la technique de cytométrie en flux optimisée pourrait être un candidat intéressant dans les études sur le diagnostic des infections bactériennes et virales.Infectious diseases are pathologies whose etiological diagnosis is often complex. The clinician must base his diagnosis on his clinical observations and link them to the patient's biological measurements. Several groups are actively seeking new biomarkers to clarify this diagnosis. It is for this purpose that flow cytometry has been used and optimized to compare the expression of new biomarkers on blood cells of infected patients or healthy subjects. Characterization of the expression mechanisms of the markers shows that the expression of CD64 on neutrophils is amplified in patients infected by a bacterium via interferon γ, whereas the expression of CD169 on monocytes is amplified in patients infected with a virus via the type I interferon family (α, β, ω). In addition, the expression of HLA-DR on monocytes seems to help the etiological identification of the infection. The work suggests that the assay of these three biomarkers combined into an optimized flow cytometry technique could be an interesting candidate in studies on the diagnosis of bacterial and viral infections
SLC44A2 : de la thrombose à l'inflammation
No full textDes études GWAS ont lié le polymorphisme SLC44A2 rs2288904 à la thrombose veineuse (TV) chez l'homme. Elle conduit à l'expression de l'épitope HNA-3a ou HNA-3b par Slc44a2, HNA-3b étant protecteur contre la TV. Slc44a2 est une protéine transmembranaire ubiquitaire et un récepteur du facteur von Willebrand (FVW) exprimé par l’endothélium inflammé. Le but est de trouver le lien entre SLC44A2 et la TV par des modèles in vivo et in vitro. La déficience en Slc44a2 n’a pas influencé la thrombose dans un modèle murin d’hypercoagulabilité. Par contre, les souris Slc44a2-/- avaient des thrombi plus petits par rapport aux souris sauvages dans un modèle de TV neutrophile (PMNs) dépendant. Nous avons testé si Slc44a2 affecte le recrutement ou l’activation des PMNs à l’endothélium, étape cruciale de la TV. Des cellules HEK293T transfectées ou des PMNs homozygotes pour l'allèle codant HNA-3a ou HNA-3b ont été perfusés sur du FVW à des flux veineux. L'expression de HNA-3a était importante pour l’adhésion du PMN au FVW. La préactivation des PMNs au LPS a amplifié cet effet. Des conditions de cisaillement spécifiques et une concentration élevée de PMNs ont agi comme un « 2ème hit » induisant la formation de « neutrophil extracellular traps ». L’importance de Slc44a2 dans le recrutement des PMNs a été confirmée par microscopie intravitale sur veinules après dégranulation endothéliale où des souris Slc44a2-/- ont montré une forte réduction du recrutement des PMNs. En montrant que Slc44a2/HNA-3a est crucial pour l’adhésion et l’activation des PMNs dans les veines sous inflammation et taux de cisaillements spécifiques, ce travail propose de nouveaux mécanismes reliant l’inflammation à la TV.Genome-wide association studies linked the SLC44A2 rs2288904 polymorphism to venous thrombosis (VT) in humans. It leads to the expression of the human neutrophil antigen (HNA)-3a or HNA-3b on Slc44a2, HNA-3b being protective from VT. Slc44a2 is a ubiquitous transmembrane protein and a receptor for von Willebrand factor (VWF), a protein expressed by the inflamed endothelium. We aimed to unravel the mechanisms linking SLC44A2 to VT using both in vitro and in vivo models. We have observed that Slc44a2 deficiency did not affect thrombosis in a hypercoagulability mouse model. However, Slc44a2-/- mice had significantly smaller thrombi than wild-type mice in a VT model where thrombosis is neutrophil (PMN)-dependent. We verified the involvement of Slc44a2 in PMN recruitment and/or activation at the vessel wall, crucial for VT initiation. Transfected HEK293T or PMNs homozygous for the HNA-3a or the HNA-3b-coding allele were perfused in flow chambers over VWF at venous shear rates. HNA-3a-expression was required for PMN adhesion on VWF. This was enhanced when PMNs were activated with LPS. Specific shear conditions and high PMN concentration worked like a “second hit” inducing the formation of PMN extracellular traps. The importance of Slc44a2 in the PMN recruitment process was then confirmed by intravital microscopy on mice mesenteric venules after endothelial degranulation. Slc44a2-/- mice showed a massive reduction in PMN recruitment at the vessel wall. By showing that Slc44a2/HNA-3a is crucial for the adhesion and activation of PMNs in veins during inflammation and when submitted to specific shears, this work proposes new mechanistic insights linking inflammation to VT
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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