Prise en charge biologique des leucémies aiguës myéloïdes (dix ans d'expérience à l'Hôpital Trousseau)

Les leucémies aiguës myéloïdes (LAM) représentent 15 à 20% des leucémies aiguës de l'enfant. Le diagnostic initial de la maladie repose sur des données biologiques précises regroupant la morphologie cellulaire, la classification FAB (French-American-British), l'immunophénotypage, la cytogénétique (classification MRC : Medical Research Council) et plus récemment la biologie moléculaire. La prise en charge des patients atteints de LAM s'est considérablement améliorée. Alors que la mortalité était très élevée dans les années 60, la survie globale est estimée actuellement à 60%.L'objectif principal de ce travail est d'analyser tous les patients traités pour une LAM de novo à l'hôpital Trousseau entre les années 1993 et 2003.Cette étude rétrospective monocentrique regroupe des données cliniques et biologiques au diagnostic de la maladie. Nous avons recherché dans notre cohorte les facteurs pronostiques tels que l'âge, l'hyperleucocytose, la présentation morphologique et les remaniements chromosomiques. Nous avons regardé l'impact de ces différents facteurs sur le devenir des patients en terme de survie globale, de rechute et de survie sans évènement. Nous avons également voulu comparer notre population aux études récentes de la littérature. Nous avons pu confirmer dans notre série l'inrérêt des classifications FAB et MRC avec un pronostic très péjoratif des LAM7-FAB et du groupe cytogénétique MRC3. Nous proposons ainsi 3 groupes pronostiques très différents : (1) groupe de bon pronostic : les leucémies avec les anomalies cytogénétiques suivantes t (8 ; 21), t (15 ; 17), inv (16) correspondant au groupe MRC1, (2) groupe de mauvais pronostic : les leucémies avec anomalies cytogénétiques impliquant les chromosomes 5 et 7, les caryotypes complexes et les leucémies mégacaryoblastiques, et (3) groupe de pronostic intermédiaire : toutes les leucémies n'appartenant à aucun de deus groupes précédents.PARIS7-Xavier Bichat (751182101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Feature extraction and reduced-order modelling of nitrogen plasma models using principal component analysis

Principal component analysis has been presented in recent research as an accurate and efficient method to reduce the complex chemistry and kinetics of large reacting mechanisms. Following the reduction, the original variables are transformed and projected onto a set of independent, orthogonal variables maximizing the total variance in the system: the principal components. However, these new variables are difficult to interpret physically and may introduce instabilities in the low dimensional representation of the manifold. In the present paper we will show the benefits of coupling PCA to a rotation method: the interpretation of the principal components can be related back to the physics. The advantages of rotation are demonstrated on a PCA reduced model for modelling dissociation and excitation processes in nitrogen shock flows.This project has received funding from the European Unions Horizon 2020 re- search and innovation program under the Marie Sklodowska-Curie grant agreement No 643134.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

PCA-Score Method for the Reduction of Collisional-Radiative Chemistry

Simulating large reacting systems such as plasma mixtures in non-equilibrium conditions, remains a challenge with the currently available computational resources. The present paper shows how principal component analysis can be applied in combination with existing reduction techniques based on coarse grain models, to reduce calculations involving the very large and complex N2-N kinetic database developed by the NASA Ames research center. A reduced model based on only a few variables will be developed starting from the detailed kinetic scheme using the 9391 species of the N-N2 mechanism in shock relaxation simulations.info:eu-repo/semantics/publishe

Reduced-order kinetic plasma models using principal component analysis: model formulation and manifold sensitivity

Plasma flows involve hundreds of species and thousands of reactions at different time scales, resulting in a very large set of governing equations to solve. Simulating large reacting systems in nonequilibrium plasma mixtures remains a challenge with the currently available computational resources. Principal component analysis (PCA) offers a general and rather simple and automated method to reduce large kinetic mechanisms by principal variable selection. This work shows how to adapt and apply the PCA-scores technique, which has its origin in the combustion field, to a collisional-radiative model. We have successfully applied this technique to argon plasmas, reducing the set of governing equations by more than 90%, leading to an important speed-up of the calculation and a reduction of computational cost.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

MG- local-PCA method for the reduction of collisional radiative argon plasma mechanism

info:eu-repo/semantics/publishe

Model reduction by PCA and Kriging

This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 643134.info:eu-repo/semantics/publishe

Lack of consensus in the choice of termination of pregnancy for Turner syndrome in France

International audienceBACKGROUND:The observed rate of termination of pregnancy (TOP) for Turner syndrome varies worldwide and even within countries. In this vignette study we quantified agreement among ten multidisciplinary prenatal diagnosis centers in Paris.METHODS:We submitted online three cases of Turner syndrome (increased nuchal translucency, normal ultrasound, aortic coarctation) to fetal medicine experts: one obstetrician, one pediatrician and one geneticist in each of the ten Parisian centers. Each case was presented in the form of a progressive clinical history with conditional links dependent upon responses. The background to each case was provided, along with the medical history of the parents and the counseling they got from medical staff. The experts indicated online whether or not they would accept the parents' request for TOP. We assessed the percentage of agreement for acceptance or refusal of TOP. We also used a multilevel logistic regression model to evaluate differences among obstetrician-gynecologists, pediatricians and cytogeneticists.RESULTS:Overall agreement among the experts to accept or refuse TOP was, respectively, 25 and 28%. The percentage of disagreement was 47%. The percentage of agreement to accept TOP was 33, 8 and 33% for obstetrician-gynecologists, pediatricians and cytogeneticists, respectively. The respective percentages of agreement to refuse TOP were 19, 47 and 26%.CONCLUSION:Our results show the lack of consensus with regard to decisions related to termination of pregnancy for Turner Syndrome. This lack of consensus in turn underscores the importance of multidisciplinary management of these pregnancies in specialized fetal medicine centers

Generation of IPi001-A/B/C human induced pluripotent stem cell lines from healthy amniotic fluid cells

Human induced Pluripotent Stem Cells (hiPSCs) represent an invaluable source of primary cells to investigate development, establish cell and disease models, provide material for regenerative medicine and allow more physiological high-content screenings. Here, we generated three healthy hiPSC control lines - IPi001-A/B/C - from primary amniotic fluid cells (AFCs), an infrequently used source of cells, which can be readily obtained from amniocentesis for the prenatal diagnosis of numerous genetic disorders. These AFCs were reprogrammed by non-integrative viral transduction. The resulting hiPSCs displayed normal karyotype and expressed classic pluripotency hallmarks

Double chromosomal translocation in an infertile man: one-step FISH meiotic segregation analysis and reproductive prognosis

International audienceBackground: The prevalence of chromosomal translocations is 1/500 in the general population. While in the vast majority of cases, carriers have a normal phenotype; they can present with difficulty conceiving due to the presence of a proportion of unbalanced gametes as a consequence of abnormal chromosomal segregation during meiosis. Since complex translocations involve three or more chromosomes, meiotic segregation leads to a greater number of possible combinations which effectively complicate both their study and therapeutic care.Case presentation: We report on the case of a male carrier of a complex homogeneous double Robertsonian translocation: 44, XY, der(13;14)(q10;q10),der(21;22)(q10;q10). We studied his meiotic segregation by FISH on spermatozoa from the initial sample, as well as following discontinuous gradient centrifugation and after incubation in an hypo-osmotic solution.Conclusion: We report a method to study in a simple single-step manner the meiotic segregation of double Robertsonian translocations in spermatozoa. Further, our results suggest that reproductive prognosis of affected individuals may be markedly improved by HOST-based sperm selection (HBSS)