La prévention du suicide chez les adolescents : Que savons-nous de son efficacité ?

Cette recherche vise à cerner l’état des connaissances actuelles sur les études évaluatives portant sur les stratégies de prévention du suicide chez les jeunes. Pour ce faire, une centaine d’écrits scientifiques se rapportant à 11 différentes stratégies ont été repérées à l’aide des méthodes habituelles. Les aspects suivants ont été examinés : facteurs visés, nature des interventions, résultats au regard de l’efficacité ou de l’implantation. Les résultats tendent à démontrer que la majorité des études portent sur des interventions visant à identifier et à référer les jeunes à risque. La recension suggère des évidences d’efficacité à diminuer les taux de suicide pour quatre stratégies mais dans l’ensemble les preuves sont limitées. Plusieurs voies d’intervention et de recherche sont proposées.This research aims at reviewing current literature concerning evaluative studies pertaining to suicide prevention strategies applicable to the young. To do this, a hundred scientific articles covering 11 strategies were searched by usual methods and the following aspects were examined : aimed factors, nature of the intervention, impact or implementation results. Results indicate that the majority of studies concern interventions aimed at identifying the young at risk. In four of the 11 strategies, the recension showed some effectiveness regarding the diminution of suicide rates but globally the evidence is weak. Various avenues for intervention and research are proposed

Optimization criteria and design of few-mode erbium-doped fibers for cladding-pumped amplifiers

We propose a novel optimization method that combines two design criteria to reduce the differential modal gain (DMG) in few-mode cladding-pumped erbium-doped fiber amplifiers (FM-EDFAs). In addition to the standard criterion that considers the mode intensity and dopant profile overlap, we introduce a second criterion that ensures that all doped regions have the same saturation behavior. With these two criteria, we define a figure-of-merit (FOM) that allows the design of MM-EDFAs with low DMG without high computational cost. We illustrate this method with the design of six-mode erbium-doped fibers (EDFs) for amplification over the C-Band targeting designs that are compatible with standard fabrication processes. The fibers have either a step-index or a staircase refractive index profile (RIP), with two ring-shaped erbium-doped regions in the core. With a staircase RIP, a fiber length of 29 m and 20 W of pump power injected in the cladding, our best design leads to a minimum gain of 22.6 dB while maintaining a DMGmax under 0.18 dB. We further show that the FOM optimization achieves a robust design with low DMG over a wide range of variations in signal power, pump power and fiber length

Familial and Clinical Correlates in Depressed Adolescents with Borderline Personality Disorder Traits

Introduction: Chart review is a low-cost, but highly informative, method to describe symptoms, treatment and risk factors associated with Borderline Personality Disorder (BPD) and to adapt screening and intervention to clinical reality. Previous chart review studies report more aggressiveness/anger and psychotic features in youths with BPD. They show that adverse family environment and parental psychopathology constitute important factors for BPD pathology. Objectives: To examine clinical characteristics of depressed BPD adolescents (12-17 years old) outpatients according to gender and to explore variables which are associated with BPD traits. Methods: A retrospective chart review using the Child and Adolescent Version of the Retrospective Diagnostic Instrument for Borderlines was conducted on 30 depressed BPD adolescents with BPD traits and 28 non-BPD depressed patients without BPD traits. Participants who reached the C-DIB threshold for BPD were included in the BPD traits group. The Child and Adolescent Version of the Retrospective Diagnostic Interview for Borderlines was used to determine the presence of BPD. Comparisons analyses were performed using Pearson’s Chi-square test. Associated factors were determined using regression analyses. Results: BPD traits participants outpatients were characterised by higher family problems (parental psychopathology, parent disagreement/argument, parent-child relational problem), more aggressive symptoms, and higher rates of family intervention and hospitalisation. A number of familial factors (parental history of delinquency, substance use, or personality disorders, having siblings, parental disagreement/argument in boys) were associated with BPD symptomatologytraits. Attention seeking and problematic functioning (does not adapt well to group activities) were also associated with BPD traits. Discussion: Our study stresses the need to assess BPD traits in adolescent psychiatric evaluation, especially in presence of aggressive behaviours, family problems and attention seeking. Our results also highlight the importance of exploring family characteristics intervention in adolescents with BPD traits

Joint Shape and Motion Estimation using Markovian Fields : Application to Multislice Computed Tomography Cardiac Imaging

We propose a method for joint surface and non-rigid motion estimation from three-dimensional dynamic sequences. Based on a surface-volume matching, it provides, from one first segmented surface, both motion and deformations of the object of interest along the whole sequence. A Markovian model, combined with a simulated annealing process, estimates the correspondences between the nodes of the surface mesh modeling the object of interest at one time and the voxels of the volume representing the object at the following time. The method has been applied to cardiac surface and motion extraction in Multislice Computed Tomography. Tests realized with simulated motion and on real data have provided promising results.Une méthode d'estimation conjointe de forme et de mouvement non rigide à partir de séquences temporelles tridimensionnelles est proposée. Reposant sur une mise en correspondance surface-volume, elle permet, à partir d'une première segmentation de l'objet d'intérêt, d'estimer le mouvement de l'objet et ses déformations sur toute la séquence temporelle d'observation. Une modélisation markovienne combinée à un algorithme de recuit simulé estime les correspondances entre les noeuds du maillage de surface modélisant l'objet à un instant et les voxels du volume représentant l'objet à l'instant suivant. La méthode a été appliquée à l'extraction de formes et de mouvements cardiaques en tomodensitométrie multibarrette. Les tests, réalisés à la fois avec des mouvements simulés et sur des données réelles, ont donné des résultats prometteurs

A small protein coded within the mitochondrial canonical gene nd4 regulates mitochondrial bioenergetics

BACKGROUND: Mitochondria have a central role in cellular functions, aging, and in certain diseases. They possess their own genome, a vestige of their bacterial ancestor. Over the course of evolution, most of the genes of the ancestor have been lost or transferred to the nucleus. In humans, the mtDNA is a very small circular molecule with a functional repertoire limited to only 37 genes. Its extremely compact nature with genes arranged one after the other and separated by short non-coding regions suggests that there is little room for evolutionary novelties. This is radically different from bacterial genomes, which are also circular but much larger, and in which we can find genes inside other genes. These sequences, different from the reference coding sequences, are called alternatives open reading frames or altORFs, and they are involved in key biological functions. However, whether altORFs exist in mitochondrial protein-coding genes or elsewhere in the human mitogenome has not been fully addressed. RESULTS: We found a downstream alternative ATG initiation codon in the + 3 reading frame of the human mitochondrial nd4 gene. This newly characterized altORF encodes a 99-amino-acid-long polypeptide, MTALTND4, which is conserved in primates. Our custom antibody, but not the pre-immune serum, was able to immunoprecipitate MTALTND4 from HeLa cell lysates, confirming the existence of an endogenous MTALTND4 peptide. The protein is localized in mitochondria and cytoplasm and is also found in the plasma, and it impacts cell and mitochondrial physiology. CONCLUSIONS: Many human mitochondrial translated ORFs might have so far gone unnoticed. By ignoring mtaltORFs, we have underestimated the coding potential of the mitogenome. Alternative mitochondrial peptides such as MTALTND4 may offer a new framework for the investigation of mitochondrial functions and diseases

Original Contribution Nitric oxide activates an Nrf2/sulfiredoxin antioxidant pathway in macrophages

a b s t r a c t a r t i c l e i n f o Peroxiredoxins (Prx's) are a family of peroxidases that maintain thiol homeostasis by catalyzing the reduction of organic hydroperoxides, H 2 O 2 , and peroxynitrite. Under conditions of oxidative stress, eukaryotic Prx's can be inactivated by the substrate-dependent oxidation of the catalytic cysteine to sulfinic acid, which may regulate the intracellular messenger function of H 2 O 2 . A small redox protein, sulfiredoxin (Srx), conserved only in eukaryotes, has been shown to reduce sulfinylated 2-Cys Prx's, adding to the complexity of the H 2 O 2 signaling network. In this study, we addressed the regulation of Srx expression in immunostimulated primary macrophages that produce both reactive oxygen species (ROS) and nitric oxide (NO • ). We present genetic evidence that NO-mediated Srx up-regulation is mediated by the transcription factor nuclear factor erythroid 2-related factor (Nrf2). We also show that the NO • /Srx pathway inhibits generation of ROS. These results reveal a link between innate immunity and H 2 O 2 signaling. We propose that an NO • /Nrf2/Srx pathway participates in the maintenance of redox homeostasis in cytokine-activated macrophages and other inflammatory settings

Les signes en société

Stéphane Breton, maître de conférencesJacques Aumont, directeur d’études Le regard et le réel : le point de vue dans le cinéma documentaire Le réalisateur de films documentaires enregistre l’image de faits dont il est le contemporaln. Ce que je vous montre, peut-il dire (tout comme l’ethno graphe), n’existe que parce que j’étais là. La conséquence, contre toute prétention positiviste, c’est que le réel n’est pas libre du point de vue porté sur lui et que le regard ne manque pas d’apparaître d..

Les signes en société

Stéphane Breton, maître de conférencesJacques Aumont, directeur d’études Le regard et le réel : le point de vue dans le cinéma documentaire Le réalisateur de films documentaires enregistre l’image de faits dont il est le contemporaln. Ce que je vous montre, peut-il dire (tout comme l’ethno graphe), n’existe que parce que j’étais là. La conséquence, contre toute prétention positiviste, c’est que le réel n’est pas libre du point de vue porté sur lui et que le regard ne manque pas d’apparaître d..

Literature Review and Case Histories of Histoplasma capsulatum var. duboisii Infections in HIV-infected Patients

African histoplasmosis during HIV infection is rare