Les TIC et la réussite éducative au collégial

"Cette recherche a été subventionnée par le Ministère de l'enseignement supérieur et de la science dans le cadre du Programme d'aide à la recherche sur l'enseignement et l'apprentissage"Comprend des références bibliographique

Les TIC et la réussite éducative au collégial : recherche /

"Cette recherche a été subventionnée par le Ministère de l'enseignement supérieur et de la science dans le cadre du Programme d'aide à la recherche sur l'enseignement et l'apprentissage"Médiagraphie: p. 97-10

Communication et soutien parental perçus dans des familles d’adolescents suicidaires et non suicidaires

Cette recherche s'intéresse à deux variables familiales liées avec la problématique suicidaire à l'adolescence, soit la communication et le soutien parental. Elle vise à comparer les perceptions d'adolescents suicidaires et non suicidaires avec celles de chacun de leurs parents, afin de mieux comprendre le lien entre ces variables et la problématique suicidaire. Les résultats confirment que la communication et le soutien parental font problème dans les familles d'adolescents suicidaires. Ces dimensions sont perçues plus négativement par ces membres en comparaison du groupe contrôle, et les écarts de perception entre l'adolescent et ses parents sont de beaucoup supérieurs dans les familles d'adolescents suicidaires. Ces données soutiennent la pertinence d'une intervention familiale lorsque des problèmes familiaux sont identifiés au moment du dépistage ou de la demande de consultation d'un adolescent suicidaire.This study focuses on two family-related variables linked to the issue of teenage suicide, namely communication and parental support. The purpose of the study is to compare the perceptions of suicidal and non-suicidal teenagers with those of their parents in order to better understand the relation between these variables and the issue of teenage suicide. Results confirm that communication and parental support represents a problem in families with suicidal teenagers. These dimensions are perceived more negatively by the latter subjects in comparison to the control group. In addition, the variations in perception between the adolescent and his or her parents are much greater in families with suicidal teens. This data supports the usefulness of family interventions when family problems are identified during detection measures or when counseling is requited by a suicidal teenager

The Alestle - Vol. 57 No. 30 - 01/11/2005

Vol. 57 No. 3

Regulatory Network Analyses Reveal Genome-Wide Potentiation of LIF Signaling by Glucocorticoids and Define an Innate Cell Defense Response

While the hypothalamo-pituitary-adrenal axis (HPA) activates a general stress response by increasing glucocorticoid (Gc) synthesis, biological stress resulting from infections triggers the inflammatory response through production of cytokines. The pituitary gland integrates some of these signals by responding to the pro-inflammatory cytokines IL6 and LIF and to a negative Gc feedback loop. The present work used whole-genome approaches to define the LIF/STAT3 regulatory network and to delineate cross-talk between this pathway and Gc action. Genome-wide ChIP-chip identified 3,449 STAT3 binding sites, whereas 2,396 genes regulated by LIF and/or Gc were found by expression profiling. Surprisingly, LIF on its own changed expression of only 85 genes but the joint action of LIF and Gc potentiated the expression of more than a thousand genes. Accordingly, activation of both LIF and Gc pathways also potentiated STAT3 and GR recruitment to many STAT3 targets. Our analyses revealed an unexpected gene cluster that requires both stimuli for delayed activation; 83% of the genes in this cluster are involved in different cell defense mechanisms. Thus, stressors that trigger both general stress and inflammatory responses lead to activation of a stereotypic innate cellular defense response

A self-inactivating retrovector incorporating the IL-2 promoter for activation-induced transgene expression in genetically engineered T-cells

BACKGROUND: T-cell activation leads to signaling pathways that ultimately result in induction of gene transcription from the interleukin-2 (IL-2) promoter. We hypothesized that the IL-2 promoter or its synthetic derivatives can lead to T-cell specific, activation-induced transgene expression. Our objective was to develop a retroviral vector for stable and activation-induced transgene expression in T-lymphocytes. RESULTS: First, we compared the transcriptional potency of the full-length IL-2 promoter with that of a synthetic promoter composed of 3 repeats of the Nuclear Factor of Activated T-Cells (NFAT) element following activation of transfected Jurkat T-cells expressing the large SV40 T antigen (Jurkat TAg). Although the NFAT3 promoter resulted in a stronger induction of luciferase reporter expression post stimulation, the basal levels of the IL-2 promoter-driven reporter expression were much lower indicating that the IL-2 promoter can serve as a more stringent activation-dependent promoter in T-cells. Based on this data, we generated a self-inactivating retroviral vector with the full-length human IL-2 promoter, namely SINIL-2pr that incorporated the enhanced green fluorescent protein (EGFP) fused to herpes simplex virus thymidine kinase as a reporter/suicide "bifunctional" gene. Subsequently, Vesicular Stomatitis Virus-G Protein pseudotyped retroparticles were generated for SINIL-2pr and used to transduce the Jurkat T-cell line and the ZAP-70-deficient P116 cell line. Flow cytometry analysis showed that EGFP expression was markedly enhanced post co-stimulation of the gene-modified cells with 1 μM ionomycin and 10 ng/ml phorbol 12-myristate 13-acetate (PMA). This activation-induced expression was abrogated when the cells were pretreated with 300 nM cyclosporin A. CONCLUSION: These results demonstrate that the SINIL-2pr retrovector leads to activation-inducible transgene expression in Jurkat T-cell lines. We propose that this design can be potentially exploited in several cellular immunotherapy applications

On the use of smart and semi-automatic interfaces to structure unstructured data

Chaque jour le volume de données numériques mondiales augmente considérablement. Plus de 75% de ces données sont non structurées. Cet article concerne la restructuration des informations graphiques contenues dans les fichiers PDF (Portable Document Format) et/ou les fichiers vectoriels. Ces documents sont détenus en général par les services de la « Smart Factory » : les bureaux d’études, les services des méthodes, les services des travaux neufs, les services de maintenance des entreprises. Pour restructurer ces données, nous proposons d’utiliser les méthodes d’Extraction des Connaissances dans les Données (ECD) ou, en anglais, Knowledge Discovery in Databases (KDD). Si, en théorie, l’utilisateur est présent lors de l’ECD, dans la pratique, ce n’est pas le cas. C’est le constat que faisait Fayard en 2003 lors de la conférence KDD. En général l’utilisateur n’est présent que lors de la phase de validation. Nous montrons pourquoi, dans la restructuration des données, il faut que l’utilisateur soit au centre du processus et présent à toutes les étapes. On peut parler d’E(A)CD pour une Extraction Anthropocentrée des Connaissances dans les Données.Every day, the volume of the world's digital data increases considerably. Over 75% of these data are non-structured. This paper is about restructuring graphic information contained in Portable Document Format (PDF) files and/or vector files. These documents are generally held by ''Smart Factory'' services: design offices, methods departments, new work departments and company maintenance services. To restructure these data, we propose using Knowledge Discovery in Databases (KDD) methods. Although, theoretically, the user is present during the KDD, in practice, this is not the case. This was observed by Fayard in 2003 at the KDD conference. Generally, the user is only present during the validation phase. We show why, in data restructuring, the user must be at the heart of the process and present at all stages. We can talk about (A)KDD for the Anthropocentric Knowledge Discovery in Databases .The first stage of this restructuring consists of extracting graphic and text objects contained in Portable Document Format (PDF) files to put them in a pivot data format. The second stage consists of coding this information in the form of an alphabet. The third stage consists of recreating the graphic and text components which are repeated in these files (which we shall refer to as graphemes). And the fourth stage consists either (1) of automatically identifying these graphemes based on knowledge or (2) presenting them so the user identifies and introduces them into the knowledge base. It is this entire restructuring process, which we will describe in this paper. As we highlighted, in this incremental process it is people who play the main role, assisted by computers and not the opposite

Assessing drug distribution in tissues expressing P-glycoprotein through physiologically based pharmacokinetic modeling: model structure and parameters determination

<p>Abstract</p> <p>Background</p> <p>The expression and activity of P-glycoproteins due to genetic or environmental factors may have a significant impact on drug disposition, drug effectiveness or drug toxicity. Hence, characterization of drug disposition over a wide range of conditions of these membrane transporters activities is required to better characterize drug pharmacokinetics and pharmacodynamics. This work aims to improve our understanding of the impact of P-gp activity modulation on tissue distribution of P-gp substrate.</p> <p>Methods</p> <p>A PBPK model was developed in order to examine activity and expression of P-gp transporters in mouse brain and heart. Drug distribution in these tissues was first represented by a well-stirred (WS) model and then refined by a mechanistic transport-based (MTB) model that includes P-gp mediated transport of the drug. To estimate transport-related parameters, we developed an original three-step procedure that allowed extrapolation of <it>in vitro </it>measurements of drug permeability to the <it>in vivo </it>situation. The model simulations were compared to a limited set of data in order to assess the model ability to reproduce the important information of drug distributions in the considered tissues.</p> <p>Results</p> <p>This PBPK model brings insights into the mechanism of drug distribution in non eliminating tissues expressing P-gp. The MTB model accounts for the main transport mechanisms involved in drug distribution in heart and brain. It points out to the protective role of P-gp at the blood-brain barrier and represents thus a noticeable improvement over the WS model.</p> <p>Conclusion</p> <p>Being built prior to <it>in vivo </it>data, this approach brings an interesting alternative to fitting procedures, and could be adapted to different drugs and transporters.</p> <p>The physiological based model is novel and unique and brought effective information on drug transporters.</p