C. Dejours. (Éd.). Conjurer la violence. Travail, violence et santé

L’objectif de cet ouvrage coordonné par Christophe Dejours est de définir une problématique des relations entre travail (ici entendu comme travail vivant au sens ergonomique du terme), violence et santé à partir de la thèse de « la centralité du travail » et d’éclairer 1) ce qui, dans le travail, provoque la violence ou l’entente et donc corrélativement la maladie (voire le suicide) ou la santé et, par déduction, 2) ce qui dans le chômage provoque la violence et donc la maladie individuelle o..

C. Dejours. (Éd.). Conjurer la violence. Travail, violence et santé

L’objectif de cet ouvrage coordonné par Christophe Dejours est de définir une problématique des relations entre travail (ici entendu comme travail vivant au sens ergonomique du terme), violence et santé à partir de la thèse de « la centralité du travail » et d’éclairer 1) ce qui, dans le travail, provoque la violence ou l’entente et donc corrélativement la maladie (voire le suicide) ou la santé et, par déduction, 2) ce qui dans le chômage provoque la violence et donc la maladie individuelle o..

Secretory Leukocyte Protease Inhibitor (SLPI) Is, like Its Homologue Trappin-2 (Pre-Elafin), a Transglutaminase Substrate

Human lungs contain secretory leukocyte protease inhibitor (SLPI), elafin and its biologically active precursor trappin-2 (pre-elafin). These important low-molecular weight inhibitors are involved in controlling the potentially deleterious proteolytic activities of neutrophil serine proteases including elastase, proteinase 3 and cathepsin G. We have shown previously that trappin-2, and to a lesser extent, elafin can be linked covalently to various extracellular matrix proteins by tissue transglutaminases and remain potent protease inhibitors. SLPI is composed of two distinct domains, each of which is about 40% identical to elafin, but it lacks consensus transglutaminase sequence(s), unlike trappin-2 and elafin. We investigated the actions of type 2 tissue transglutaminase and plasma transglutaminase activated factor XIII on SLPI. It was readily covalently bound to fibronectin or elastin by both transglutaminases but did not compete with trappin-2 cross-linking. Cross-linked SLPI still inhibited its target proteases, elastase and cathepsin G. We have also identified the transglutamination sites within SLPI, elafin and trappin-2 by mass spectrometry analysis of tryptic digests of inhibitors cross-linked to mono-dansyl cadaverin or to a fibronectin-derived glutamine-rich peptide. Most of the reactive lysine and glutamine residues in SLPI are located in its first N-terminal elafin-like domain, while in trappin-2, they are located in both the N-terminal cementoin domain and the elafin moiety. We have also demonstrated that the transglutamination substrate status of the cementoin domain of trappin-2 can be transferred from one protein to another, suggesting that it may provide transglutaminase-dependent attachment properties for engineered proteins. We have thus added to the corpus of knowledge on the biology of these potential therapeutic inhibitors of airway proteases

The dystroglycan: Nestled in an adhesome during embryonic development

AbstractInvertebrate and vertebrate development relies on complex processes that require many coordinated cell functions including cell adhesion, migration, proliferation and polarization. These processes depend on tissues and are spatio-temporally regulated by specific interactions between cells and between cells and the extracellular matrices. The dystroglycan, a transmembrane receptor that binds multiple extracellular matrix proteins, is expressed from oogenesis to organogenesis. There are increasing data suggesting that the axis, consisting of extracellular component–dystroglycan–cytoplasmic proteins, controls both the adhesion of cells to matrices as well as the transduction of signals coming from or directed to matrices. In this article, we review current advances leading to consider that the dystroglycan is a key protein nestled in an adhesome involved in mechanisms of cell adhesion during embryonic development

A novel di-acidic motif facilitates ER export of the syntaxin SYP31

It is generally accepted that ER protein export is largely influenced by the transmembrane domain (TMD). The situation is unclear for membrane-anchored proteins such as SNAREs, which are anchored to the membrane by their TMD at the C-terminus. For example, in plants, Sec22 and SYP31 (a yeast Sed5 homologue) have a 17 aa TMD but different locations (ER/Golgi and Golgi), indicating that TMD length alone is not sufficient to explain their targeting. To establish the identity of factors that influence SNARE targeting, mutagenesis and live cell imaging experiments were performed on SYP31. It was found that deletion of the entire N-terminus domain of SYP31 blocked the protein in the ER. Several deletion mutants of different parts of this N-terminus domain indicated that a region between the SNARE helices Hb and Hc is required for Golgi targeting. In this region, replacement of the aa sequence MELAD by GAGAG or MALAG retained the protein in the ER, suggesting that MELAD may function as a di-acidic ER export motif EXXD. This suggestion was further verified by replacing the established di-acidic ER export motif DLE of a type II Golgi protein AtCASP and a membrane-anchored type I chimaera, TMcCCASP, by MELAD or GAGAG. The MELAD motif allowed the proteins to reach the Golgi, whereas the motif GAGAG was found to be insufficient to facilitate ER protein export. Our analyses indicate that we have identified a novel and transplantable di-acidic motif that facilitates ER export of SYP31 and may function for type I and type II proteins in plants

Collective models of labor supply with nonconvex budget sets and nonparticipation : a calibration approach.

We suggest a methodology to calibrate a collective model with household-specific bargaining rules and marriage-specific preferences that incorporate leisure externalities. The empirical identification relies on the assumption that some aspects of individual preferences remain the same after marriage, so that estimation on single individuals can be used. The procedure maps the complete Pareto frontier of each household in the dataset and we define alternative measures of a power index. The latter is then regressed on relevant bargaining factors, including a set of variables retracing the potential relative contributions of the spouses to household disposable income. In its capacity to handle complex budget sets and labor force participation decisions of both spouses, this framework allows the comparison of unitary and collective predictions of labor supply reactions and welfare changes entailed by fiscal reforms in a realistic setting (see Michal Myck et al., 2006; Denis Beninger et al., 2006).Collective model; Household labor supply; Intrahousehold allocations; Tax reform;

Does the representation of household behavior matter for welfare analysis of tax-benefit policies? : an introduction.

A widely shared intuition holds that individual control over money matters for the decision process within the household and the subsequent distribution of resources and welfare. As a consequence, there are good reasons to depart from the unitary model of the household and to explore the possibilities offered by models of the family accounting for several decision makers in the household and for the potential impact of tax reforms on the balance of power. This paper summarizes both the methodological and empirical findings presented in the next three papers of this special issue of the Review of the Economics of the Household. This series of contributions primarily entails a concrete comparison of the policy implications of the choice between the unitary and a particular multi-person representation: the collective representation. On the one hand, it suggests a methodology to implement the collective model of labor supply in a realistic context where participation is modeled together with working hours, and where the full tax-benefit system is accounted for. On the other hand, the empirical part relies on comprehensive simulations of tax reforms in Belgium, France, Germany, Italy, Spain, and the United Kingdom, and allows to quantify the distortions that may affect policy recommendations based on the unitary model.Collective model; Household labor supply; Intra household allocations; Tax reform;

Precise mapping of the CD95 pre-ligand assembly domain.

International audiencePre-association of CD95 at the plasma membrane is mandatory for efficient death receptor signaling. This homotrimerization occurs through self-association of an extracellular domain called the pre-ligand assembly domain (PLAD). Using novel molecular and cellular tools, we confirmed that CD95-PLAD is necessary to promote CD95 multimerization and plays a pivotal role in the transmission of apoptotic signals. However, while a human CD95 mutant deleted of the previously described PLAD domain (amino acids 1 to 66) fails to interact with its wild-type counterpart and trigger autonomous cell death, deletion of amino acids 1 to 42 does not prevent homo- or hetero (human/mouse)-oligomerization of CD95, and thus does not alter transmission of the apoptotic signal. Overall, these findings indicate that the region between amino acids 43 to 66 corresponds to the minimal motif involved in CD95 homotypic interaction and is necessary to convey an efficient apoptotic signal. Interfering with this PLAD may represent a new therapeutic strategy for altering CD95-induced apoptotic and non-apoptotic signals

Suivi robuste d'objets en temps-réel : une approche hybride 2D-3D

Dans cet article, nous présentons une méthode originale de suivi d'objets complexes approximativement modélisés par un polyèdre. L'approche repose sur l'estimation du mouvement de l'objet dans l'image, ainsi que sur un calcul de pose. La méthode proposée permet un suivi fiable et robuste en temps réel comme le montrent les résultats présentés

Early calcium increase triggers the formation of olfactory long-term memory in honeybees

<p>Abstract</p> <p>Background</p> <p>Synaptic plasticity associated with an important wave of gene transcription and protein synthesis underlies long-term memory processes. Calcium (Ca²⁺) plays an important role in a variety of neuronal functions and indirect evidence suggests that it may be involved in synaptic plasticity and in the regulation of gene expression correlated to long-term memory formation. The aim of this study was to determine whether Ca²⁺is necessary and sufficient for inducing long-term memory formation. A suitable model to address this question is the Pavlovian appetitive conditioning of the proboscis extension reflex in the honeybee <it>Apis mellifera, </it>in which animals learn to associate an odor with a sucrose reward.</p> <p>Results</p> <p>By modulating the intracellular Ca²⁺concentration ([Ca²⁺]i) in the brain, we show that: (i) blocking [Ca²⁺]i increase during multiple-trial conditioning selectively impairs long-term memory performance; (ii) conversely, increasing [Ca²⁺]i during single-trial conditioning triggers long-term memory formation; and finally, (iii) as was the case for long-term memory produced by multiple-trial conditioning, enhancement of long-term memory performance induced by a [Ca²⁺]i increase depends on <it>de novo </it>protein synthesis.</p> <p>Conclusion</p> <p>Altogether our data suggest that during olfactory conditioning Ca²⁺is both a necessary and a sufficient signal for the formation of protein-dependent long-term memory. Ca²⁺therefore appears to act as a switch between short- and long-term storage of learned information.</p