49 research outputs found

    Solving multi-criteria decision problems under possibilistic uncertainty using optimistic and pessimistic utilities

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    International audienceThis paper proposes a qualitative approach to solve multi-criteria decision making problems under possibilistic uncertainty. De-pending on the decision maker attitude with respect to uncertainty (i.e. optimistic or pessimistic) and on her attitude with respect to criteria (i.e. conjunctive or disjunctive), four ex-ante and four ex-post decision rules are dened and investigated. In particular, their coherence w.r.t. the principle of monotonicity, that allows Dynamic Programming is studied

    Experience du service de medecine nucleaire sahloul sousse dans la prise en charge des carcinomes differencies de la thyroïde a thyroglobuline elevee.

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    But : L’objectif de notre travail est de présenter notre expérience dans la prise en charge des cancer différencié de la thyroïde (CDT) à Thyroglobuline (Tg) élevée, tout en identifiant les paramètres modifiant l’efficacité de l’Irathérapie et la valeur seuil de la Tg permettant avec un balayage post thérapeutique négatif de conclure à une rémission.Matériels et méthodes : Il s’agit d’une étude rétrospective portant sur 150 patients opérés pour CDT, suivis entre 1990 et 2006 et présentant une Tg>2ng/ml.Résultats : Il s’agit de 122 femmes et 28 hommes. L’âge moyen était de 52 ans. La Tg ne dépendait pas du type histologique mais il existait une relation statistiquement significative entre la Tg et la taille tumorale, l’atteinte ganglionnaire, l’extension locorégionale, la présence de métastases et le stade TNM. La réponse thérapeutique des CDT avec une Tg élevée dépendait de l’âge des patients, des caractéristiques anatomopathologiques de la tumeur et des valeurs de la Tg.Conclusion : L’efficacité ablative est optimisée par des cures d’iode 131 qui doivent être prolongées tant que la Tg reste élevée. La surveillance à vie, au cours de la quelle on exige des seuils de Tg infèrieurs à 2ng/ml, est nécessaire. Mots clés : Cancers différenciés de la thyroide, Thyroglobuline, Irathérapie, Pronostic, Surveillance.Purpose: The aim of our work is to present our experience in the management of differentiated thyroid cancer (DTC) with high thyroglobulin (Tg) , to identify parameters changing iodine effectiveness and Tg threshold with negative post treatment scan conclude to remission.Materials and Methods: This is a retrospective study of 150 patients undergoing CDT, followed between 1990 and 2006 and having a Tg > 2ng/ml .Results: Our study concerns 122 women and 28 men. The average age was 52 years . Tg value does not depend on the histological type but there was a statistically significant relationship between Tg and tumor size, lymph node involvement, locoregional , metastasis and TNM stage . The therapeutic response of CDT with a high Tg was dependent on the age of patients, the pathological characteristics of the tumor and the Tg values ofConclusion: The ablative efficiency is optimized by 131 cures iodine should be extended until the Tg remains high. Monitoring life is necessary and the thresholds Tg below 2ng/ml is required.Keywords: Differentiated thyroid Cancers, Thyroglobulin, Iodine 131, Prediction, Monitoring

    Synthesis and characterization of azo-containing organometallic thin films for all optical switching applications

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    International audienceNovel photoresponsive materials based on azo-containing bifunctional ruthenium-acetylides have been synthesized. All optical switching based on the Optical Kerr Effect in the organometallic thin films based on ruthenium(II) acetylides containing an azobenzene moiety as a photochromic unit in the main pi-conjugated system dispersed in a poly(methyl methacrylate) matrix has been observed. The excitation beam was delivered from a picosecond laser at wavelength 532 nm while dynamics of induced sample birefringence was probed by a non-absorbed linearly polarized beam of cw He-Ne laser (632.8 nm). The influence of ruthenium part on dynamics of molecular motions has been shown

    Facteurs predictifs de l’efficacite ablative de l’iode 131 dans les cancers differencies de la thyroïde

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    La prise en charge des cancers différenciés de la thyroïde (CDT) comporte souvent une radiothérapie métabolique à l’iode131 (IRA-thérapie). Le but de ce travail est d’évaluer le caractère prédictif des différents éléments anatomopathologiques, de la classification pTNM et de la stadification pronostique sur l’activité ablative requise d’iode131. Notre travail est une étude analytique rétrospective portant sur 275 cas de CDT ayant subit une thyroïdectomie totale. Tous ces patients ont eu une ou plusieurs activités ablatives. Nous avons cherché – au moyen d’une analyse statistique par test de Khi2 ou test Anova – toute corrélation entre les éléments de l’examen anatomopathologique de la tumeur, la classe pTNM, le stade pronostique correspondant d’une part  et l’efficacité de l’irathérapie ablative d’autre part. Dans notre série, une activité ablative plus élevée est nécessaire lorsque la taille du foyer tumoral dépasse les 6 cm (p=0,012), en cas de dépassement de la graisse péri thyroïdienne (

    Numerical and experimental transition results evaluation for a morphing wing and aileron system

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    A new wing-tip concept with morphing upper surface and interchangeable conventional and morphing ailerons was designed, manufactured, bench and wind tunnel tested. The development of this wing tip model was performed in the frame of an international CRIAQ project, and the purpose was to demonstrate the wing upper surface and aileron morphing capabilities in improving the wing tip aerodynamic performances. During numerical optimization with ‘in-house’ genetic algorithm software, and during wind tunnel experimental tests, it was demonstrated that the air flow laminarity over the wing skin was promoted, and the laminar flow was extended with up to 9% of the chord. Drag coefficient reduction of up to 9% was obtained when the morphing aileron was introduced

    A Concerted HIF-1α/MT1-MMP Signalling Axis Regulates the Expression of the 3BP2 Adaptor Protein in Hypoxic Mesenchymal Stromal Cells

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    Increased plasticity, migratory and immunosuppressive abilities characterize mesenchymal stromal cells (MSC) which enable them to be active participants in the development of hypoxic solid tumours. Our understanding of the oncogenic adaptation of MSC to hypoxia however lacks the identification and characterization of specific biomarkers. In this study, we assessed the hypoxic regulation of 3BP2/SH3BP2 (Abl SH3-binding protein 2), an immune response adaptor/scaffold protein which regulates leukocyte differentiation and motility. Gene silencing of 3BP2 abrogated MSC migration in response to hypoxic cues and generation of MSC stably expressing the transcription factor hypoxia inducible factor 1alpha (HIF-1α) resulted in increased endogenous 3BP2 expression as well as cell migration. Analysis of the 3BP2 promoter sequence revealed only one potential HIF-1α binding site within the human but none in the murine sequence. An alternate early signalling cascade that regulated 3BP2 expression was found to involve membrane type-1 matrix metalloproteinase (MT1-MMP) transcriptional regulation which gene silencing abrogated 3BP2 expression in response to hypoxia. Collectively, we provide evidence for a concerted HIF-1α/MT1-MMP signalling axis that explains the induction of adaptor protein 3BP2 and which may link protein binding partners together and stimulate oncogenic MSC migration. These mechanistic observations support the potential for malignant transformation of MSC within hypoxic tumour stroma and may contribute to evasion of the immune system by a tumour

    CD146 expression is associated with a poor prognosis in human breast tumors and with enhanced motility in breast cancer cell lines.

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    INTRODUCTION: Metastasis is a complex process involving loss of adhesion, migration, invasion and proliferation of cancer cells. Cell adhesion molecules play a pivotal role in this phenomenon by regulating cell-cell and cell-matrix interactions. CD146 (MCAM) is associated with an advanced tumor stage in melanoma, prostate cancer and ovarian cancer. Studies of CD146 expression and function in breast cancer remain scarce except for a report concluding that CD146 could act as a tumor suppressor in breast carcinogenesis. METHODS: To resolve these apparent discrepancies in the role of CD146 in tumor cells, we looked at the association of CD146 expression with histoclinical features in human primary breast cancers using DNA and tissue microarrays. By flow cytometry, we characterized CD146 expression on different breast cancer cell lines. Using siRNA or shRNA technology, we studied functional consequences of CD146 downmodulation of MDA-MB-231 cells in migration assays. Wild-type, mock-transfected and downmodulated transfected cells were profiled using whole-genome DNA microarrays to identify genes whose expression was modified by CD146 downregulation. RESULTS: Microarray studies revealed the association of higher levels of CD146 with histoclinical features that belong to the basal cluster of human tumors. Expression of CD146 protein on epithelial cells was detected in a small subset of cancers with histoclinical features of basal tumors. CD146+ cell lines displayed a mesenchymal phenotype. Downmodulation of CD146 expression in the MDA-MB-231 cell line resulted in downmodulation of vimentin, as well as of a set of genes that include both genes associated with a poor prognosis in a variety of cancers and genes known to promote cell motility. In vitro functional assays revealed decreased migration abilities associated with decreased CD146 expression. CONCLUSIONS: In addition to its expression in the vascular compartment, CD146 is expressed on a subset of epithelial cells in malignant breast. CD146 may directly or indirectly contribute to tumor aggressiveness by promoting malignant cell motility. Changes in molecular signatures following downmodulation of CD146 expression suggest that CD146 downmodulation is associated with the reversal of several biological characteristics associated with epithelial to mesenchymal transition, and the phenomenon associated with the metastatic process.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
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