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Insalubrite au XIX, Indignite au Xxeme siecle De la statistique a la capacite d'agir Yankel Fijalkow (CRH LAVUE) Bruno Maresca (Sciences Po) La question des logements insalubres a ete abordee des le milieu du 19 eme siecle. Aujourd'hui cette question resurgit tant dans les statistiques etablies sur la base des recensements de l'INSEE que dans les rapports de la Fondation Abbe Pierre. Le chiffre approchant de 4 millions de mal loges est stable depuis le milieu des annees 1990. Il a trouve une nouvelle actualite en 2018 avec l'effondrement de deux immeubles a Marseille . Peut-on comparer ou mettre en resonnance ces deux periodes historiques ? Dans cet article nous souhaitons montrer que dans l'enchainement historique des categories de pensee-taudis, habitat insalubre, logement decent, mal logement, habitat indigne-, se jouent les transformations des modes d'intervention publique face a des situations que l'on a cru, a plusieurs moments de l'Histoire, pouvoir eradiquer.

Heating standards and energy transition; an investigation on the transactions of home dwellers. The debate about the notion of energy transition questions the lack of consideration by public authorities of the discrepancy between household heating practices and the rules put forward by these same authorities. This paper describes the main results of recent surveys and proposes to highlight them by examining the evolution of comfort standards in housing and the way they are produced. Mobilizing the social transaction theory enabled us to reveal the difficulty for housing policies to develop shared positions. We showed that household practices, which result in house heating temperatures actually higher than the 19 degrees norm, form a real critique of the energy transition theory. In being unable to have the norm accepted in household behavior despite the urgency of controlling the demand for energy, the energy transition theory proves to be unrealistic in overlooking the mechanisms of social practice., On interroge dans cet article la notion de transition énergétique en explorant la non-prise en compte par les pouvoirs publics de l'écart entre les pratiques de chauffage des ménages et les dispositifs d'injonctions mis en oeuvre. Après avoir discuté les résultats d'enquêtes récentes sur les températures de chauffe des ménages, on revisite l'évolution et le mode de production des normes de confort dans l'habitat et on analyse les pratiques de chauffage à l'aune de la notion de transaction sociale. Les pratiques des ménages, qui conduisent à des températures réelles de chauffe des habitations plus élevées que les 19 degrés de la norme, constituent une critique de fait de la transition énergétique. Ne parvenant pas à « faire passer la norme » dans les comportements en dépit des urgences de la maîtrise de la demande en énergie, la transition énergétique se révèle velléitaire par ignorance des mécanismes de la pratique sociale.

International audience; 4e de couverture : On le sait bien, les mots ne sont jamais neutres. Qu’il s’agisse de politique publique, d’urbanisme participatif, de marketing territorial ou de labellisation de projets urbains, nombre de pratiques professionnelles nous ramènent au pouvoir du langage, à l’assurance qu’il apporte aux échanges aussi bien qu’au doute qu’il peut installer. Pourtant, les questions langagières sont pour le moins négligées par la recherche urbaine.Pour remédier à ce manque, des architectes, des urbanistes, des sociologues, des historiens et des géographes se penchent ici sur ces termes qui inspirent et orientent la production et la pensée de la ville. Ils s’interrogent sur la façon dont les mots font évoluer les représentations urbaines, parfois même à travers une certaine scénarisation. Les auteurs soulèvent aussi la question des phénomènes émergents qui nécessitent un lexique original. Au fond, comment nommer le nouveau ? Et surtout : les mots nouveaux s’appliquent‐ils à des situations réellement inédites ?

Le mode de vie est une prenotion sociologique fortement mobilisee du fait des mutations technologiques et economiques et des debats sur la transition ecologique. Sa transformation est-elle un enjeu collectif ou plutot une responsabilite individuelle ? On eclaire cette question par une mise a plat de la polysemie des termes « genre de vie », « mode de vie », « style de vie », et l’on remonte leur genealogie pour clarifier ce concept. Le mode de vie est un systeme structurant et differenciant a l’interieur duquel les styles de vie sont une dynamique de renouvellement des manieres d’etre. La transition ecologique ne prendra un tournant decisif que si le changement se trouve engage au cœur de la structure du mode de vie par une revolution de l’architecture du vivre-ensemble.

The development of strategies to reduce the load of unwanted bacteria is a fundamental challenge in industrial processing, environmental sciences and medical applications. Here, we report a new method to sequester motile bacteria from a liquid, based on passive, deployable micro-traps that confine bacteria using micro-funnels that open into trapping chambers. Even in low concentrations, micro-traps afford a 70% reduction in the amount of bacteria in a liquid sample, with a potential to reach >90% as shown by modelling improved geometries. This work introduces a new approach to contain the growth of bacteria without chemical means, an advantage of particular importance given the alarming growth of pan-drug-resistant bacteria., Scientific Reports, 7, ISSN:2045-2322

We demonstrated previously that expression of a single trans-membrane region of the Δ(12) -desaturase gene of Synechocystis sp. PCC 6803 in Salmonella enterica serovar Typhimurium (Salmonella Typhimurium) altered the membrane physical state of this pathogen, induced a significant change in the pattern of mRNA transcription of major heat shock genes, and inhibited pathogen growth inside murine macrophages. In this study, we demonstrate that injection of the modified Salmonella strain [Stm(pBAD200)] into C57Bl6j mice is safe. Survival of mice was associated with bacterial clearance, an increased number of splenic leukocytes, and high levels of interleukin-12, interferon γ and tumor necrosis factor α in spleens as well as in sera. Furthermore, Stm(pBAD200)-injected mice developed a Salmonella-specific antibody and Th1-like responses. Mice challenged with Stm(pBAD200) are protected from systemic infection with Salmonella wild-type. Similarly, mice infected with Stm(pBAD200) by the oral route survived when challenged with an oral lethal dose of Salmonella wild-type. The avirulent Stm(pBAD200) phenotype is associated with a remarkable change in the expression of the hilC, hilD, hilA, invF and phoP genes, among others, whose products are required for invasion and replication of Salmonella inside phagocytic cells. These data demonstrate the use of trans-membrane peptides to generate attenuated strains, providing a potential novel strategy to develop vaccines for both animal and human use.

Cet article vise a proposer une refondation theorique et empirique de la notion de mode de vie, et a la mobiliser comme grille de lecture des problematiques auxquelles se confronte le projet de transition energetique. La these qui est defendue ici est que la notion de mode de vie est souvent reduite, notamment dans le projet de transition energetique, a la seule dimension du comportement de l’usager et consommateur d’energie, deconnecte des cadres materiels et normatifs qui orientent et surdeterminent les pratiques individuelles et collectives. On propose au contraire d’apprehender le mode de vie comme un ensemble de dispositifs a la fois materiels (forme d’habitat, reseaux, objets techniques ...), et ideels (representations, valeurs ...), sur lesquels repose l’organisation de la vie sociale (le logement, la mobilite, l’alimentation, l’education ...) et qui designent implicitement la « normalite », au sens des usages et pratiques habituelles au sein de la societe consideree. C’est en prenant en compte la dimension du mode de vie que les conditions du passage a un nouveau systeme energetique, qui definit la transition, peuvent etre explorees avec plus de precision.

The classic heat shock (stress) response (HSR) was originally attributed to protein denaturation. However, heat shock protein (Hsp) induction occurs in many circumstances where no protein denaturation is observed. Recently considerable evidence has been accumulated to the favor of the “Membrane Sensor Hypothesis” which predicts that the level of Hsps can be changed as a result of alterations to the plasma membrane. This is especially pertinent to mild heat shock, such as occurs in fever. In this condition the sensitivity of many transient receptor potential (TRP) channels is particularly notable. Small temperature stresses can modulate TRP gating significantly and this is influenced by lipids. In addition, stress hormones often modify plasma membrane structure and function and thus initiate a cascade of events, which may affect HSR. The major transactivator heat shock factor-1 integrates the signals originating from the plasma membrane and orchestrates the expression of individual heat shock genes. We describe how these observations can be tested at the molecular level, for example, with the use of membrane perturbers and through computational calculations. An important fact which now starts to be addressed is that membranes are not homogeneous nor do all cells react identically. Lipidomics and cell profiling are beginning to address the above two points. Finally, we observe that a deregulated HSR is found in a large number of important diseases where more detailed knowledge of the molecular mechanisms involved may offer timely opportunities for clinical interventions and new, innovative drug treatments. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.

Here, we report a procedure to obtain novel artificial materials using either fungal or isolated tobacco cells in association with different percentages of carbon nanotubes. The electrical, mechanical, and optical properties of these materials have been determined. The produced bio-nano-composite materials have linear electrical characteristics, high temperature stability up to 180 °C, linear increase of the electrical conductivity with increasing temperature and, in one case, also optical transparency. Using tobacco cells, we obtained a material with low mass density and mechanical properties suitable for structural applications along with high electrical conductivity. We also present theoretical models both for their mechanical and electrical behavior. These findings report a procedure for the next generation bio-nano-composite materials.

We propose that the sudden emergence of metazoans during the Cambrian was due to the appearance of a complex genome architecture that was capable of computing. In turn, this made defining recursive functions possible. The underlying molecular changes that occurred in tandem were driven by the increased probability of maintaining duplicated DNA fragments in the metazoan genome. In our model, an increase in telomeric units, in conjunction with a telomerase-negative state and consequent telomere shortening, generated a reference point equivalent to a non-reversible counting mechanism.

A Candida albicans/multiwalled carbon nanotube (Ca/MWCNTs) composite material has been produced. It can be used as a temperature-sensing element operative in a wide temperature range (up to 100 °C). The Ca/MWCNTs composite has excellent linear current-voltage characteristics when combined with coplanar gold electrodes. We used growing cells of C. albicans to structure the CNT-based composite. The fungus C. albicans combined with MWCNTs coprecipitated as an aggregate of cells and nanotubes that formed a viscous material. Microscopic analyses showed that Ca/MWCNTs formed a sort of artificial tissue. Slow temperature cycling was performed up to 12 days showing a stabilization of the temperature response of the material.

Reference electronique MARESCA, Bruno ; GAUDET, Francoise ; et EVANS, Christophe. Chapitre III. La permanence du livre face a Internet In : Les bibliotheques municipales en France apres le tournant Internet : Attractivite, frequentation et devenir [en ligne]. Paris : Editions de la Bibliotheque publique d’information, 2007 (genere le 04 juin 2015). Disponible sur Internet : . ISBN : 9782842461577.

Reference electronique MARESCA, Bruno ; GAUDET, Francoise ; et EVANS, Christophe. Liste des tableaux et graphiques In : Les bibliotheques municipales en France apres le tournant Internet : Attractivite, frequentation et devenir [en ligne]. Paris : Editions de la Bibliotheque publique d’information, 2007 (genere le 04 juin 2015). Disponible sur Internet : . ISBN : 9782842461577.

Dans la presentation faite jusqu’ici de l’evolution de la frequentation des bibliotheques, on a peu considere l’incidence de l’offre et des transformations de celle-ci au fil du temps. En France, on part souvent du principe que le developpement des pratiques culturelles procede principalement de la capacite des individus a entretenir par eux-memes un commerce avec le monde du savoir et de l’art apres avoir ete inities par le cursus educatif (familial et scolaire). L’offre, c’est-a-dire le tra...

Reference electronique MARESCA, Bruno ; GAUDET, Francoise ; et EVANS, Christophe. Chapitre V. Les determinants de la frequentation In : Les bibliotheques municipales en France apres le tournant Internet : Attractivite, frequentation et devenir [en ligne]. Paris : Editions de la Bibliotheque publique d’information, 2007 (genere le 04 juin 2015). Disponible sur Internet : . ISBN : 9782842461577.

Reference electronique MARESCA, Bruno ; GAUDET, Francoise ; et EVANS, Christophe. Les auteurs / Remerciements In : Les bibliotheques municipales en France apres le tournant Internet : Attractivite, frequentation et devenir [en ligne]. Paris : Editions de la Bibliotheque publique d’information, 2007 (genere le 04 juin 2015). Disponible sur Internet : . ISBN : 9782842461577.

Reference electronique MARESCA, Bruno ; GAUDET, Francoise ; et EVANS, Christophe. Chapitre I. La frequentation des bibliotheques municipales en 2005 In : Les bibliotheques municipales en France apres le tournant Internet : Attractivite, frequentation et devenir [en ligne]. Paris : Editions de la Bibliotheque publique d’information, 2007 (genere le 04 juin 2015). Disponible sur Internet : . ISBN : 9782842461577.

Etude sur l’usage des bibliotheques et mediatheques municipales Novembre 2005 1. Sexe de l’interviewe : 1 Homme 2 Femme 2. Quel est votre âge (en annees revolues) ? 1 15-19 ans 2 20-24 ans 3 25-34 ans 4 35-44 ans 5 45-54 ans 6 55-64 ans 7 65 ans et plus 3. Quel est votre lien avec le chef de famille ? 1 Lui-meme 2 Son conjoint 3 Un enfant 4 Autre (precisez) : 4. Au cours de votre vie, avez-vous deja eu l’occasion d’aller dans… ? 1 La ou les bibliotheque(s) ou mediatheque(s) municipale(s) de ...

National audience; Le Haut Conseil de la santé publique (HCSP) présente son rapport d’évaluation de 10 ans de politique de lutte contre le cancer (2004-2014).À partir de l’analyse des six axes clés de la politique de lutte contre le cancer (Recherche, Observation, Prévention, Dépistage, Soins, Qualité de vie), le HCSP s’est, plus particulièrement attaché à répondre aux quatre questions principales suivantes :• Quel a été l’impact des deux premiers Plans cancer en termes de réduction des inégalités de santé ?• Dans quelle mesure un plan thématique et un opérateur dédié (Institut national du Cancer – INCa) ont-ils constitué un progrès ?• L’expérience acquise dans ce champ est-elle extrapolable à d’autres maladies chroniques ?• Quels enseignements peut-on tirer d’une comparaison avec les expériences étrangères, notamment sur l’organisation des dépistages ?Cette évaluation a conduit à formuler soixante recommandations visant à améliorer la prévention, le dépistage et la prise en charge des cancers, à garantir des soins personnalisés et efficaces, à améliorer la qualité de vie des patients pendant et après le cancer, et à réduire les inégalités sociales et territoriales de santé face au cancer. Il s’agit aussi de renforcer larecherche et le recueil des données en cancérologie et d’optimiser le pilotage et la gouvernance concernant cette maladie.Globalement, ces recommandations sont cohérentes avec les orientations du Plan cancer 2014-2019 actuellement en cours.Cette évaluation menée par dix professionnels, membres ou non du HCSP a fait appel à environ soixante auditions d’acteurs clés de la lutte contre le cancer, à une étude détaillée des principaux documents en lien avec cette thématique et à une étude qualitative de parcours individuels auprès de trente patients et de leur entourage professionnel et personnel.

Les politiques de maintien dans l’emploi visent a traiter les situations ou des problemes de sante ou de handicaps sont susceptibles de faire peser un risque sur l’emploi du salarie. Le travail de recherche engage par le CREDOC a la demande de l’Institut national du cancer (INCa) visait a apporter un eclairage sur la maniere dont la question du maintien dans l’emploi se pose pour les differents acteurs de l’entreprise et comment elle s’inscrit dans les pratiques professionnelles. La recherche a porte sur neuf etablissements de grandes entreprises en France et en Allemagne. Des entretiens approfondis y ont ete conduits aupres de tous les acteurs intervenant dans les processus de retour a l’emploi. Les obligations legales qui impliquent des actions de maintien dans l’emploi en France, telles que l’obligation de reclassement, l’emploi de personnes handicapees ou l’emploi des seniors, ne renvoient pas a un champ de pratiques unifie autour de l’objectif de maintien dans l’emploi dans l’entreprise francaise. Les etablissements se caracterisent par une gestion au cas par cas du maintien dans l’emploi, peu anticipee. Les situations favorables ou la solidarite entre collegues joue a plein soulignent en creux les processus discretionnaires a l’œuvre en l’absence de procedure formalisee, et dans un contexte d’exigence de productivite croissante.

Transcriptional response of desaturase genes to low temperature was investigated in the dimorphic fungus Mucor rouxii. The two morphological forms of M. rouxii, yeast-like and mycelial cells containing different fatty acid profiles were shifted from 30 to 10°C. Both cultures exhibited significantly altered fatty acid composition, whose content in polyunsaturated fatty acids increased as consequence of the temperature shift and was accompanied by a reduction of C18:1Δ(9) about 2 h after the temperature shift. These changes were particularly significant in phosphatidylcholine and phosphatidylethanolamine fractions. Moreover, the fatty acid profiles of monoacylglycerol and diacylglycerol were also modulated in response to the lower temperature of incubation. The changes of membrane lipids of M. rouxii were due to the cold-induced expression of Δ(9)-, Δ(12)- and Δ(6)-desaturase genes. Although the mRNA levels of the three desaturases were transiently induced by lowering the temperature, the pre-existing composition of fatty acid profiles of mycelial and yeast-like forms of M. rouxii may have lead to different expression profiles of desaturase genes that modified their membrane physical state under cold shock. While expression of Δ(12)-desaturase gene contributed mainly to cold acclimation of mycelia, Δ(9)-desaturase expression was the main transcript identified in the yeast-like culture after temperature shift.

Background and purpose: The resistance of human colon adenocarcinoma cells to antineoplastic agents may be related to the high endogenous expression of stress proteins, including the family of heat shock proteins (HSPs). Recently, a quinone-based pentacyclic derivative, DTNQ-Pro, showed high cytotoxic activity in human colon carcinoma cell lines. The aim of the present study was to determine the precise cellular mechanisms of this cytotoxic action of DTNQ-Pro. Experimental approach: Using human colorectal carcinoma-derived Caco-2 cells as a model, we studied the effects of DTNQ-Pro on cellular viability and oxidative stress; HSP70 and HSP27 accumulation; and cell cycle, differentiation and apoptosis. Key results: Incubation of Caco-2 cells with DTNQ-Pro reduced cell growth and increased the levels of reactive oxygen species in mitochondria. After 48 h of treatment, cells surviving showed an increased expression of Mn-superoxide dismutase (SOD), nitric oxide production and membrane lipid peroxidation. Treatment with DTNQ-Pro decreased HSP70 expression, and redistributed HSP27 and vimentin within the cell. DTNQ-Pro down-regulated the expression of A and B cyclins with arrest of the cell cycle in S phase and increased cellular differentiation. A second treatment of Caco-2 cells with DTNQ-Pro induced cellular death by activation of the apoptotic pathway. Conclusions and implications: DTNQ-Pro causes Caco-2 cell death by induction of apoptosis via inhibition of HSP70 accumulation and the intracellular redistribution of HSP27. These findings suggest the potential use of DTNQ-Pro in combination chemotherapy for colon cancer.

Conventional approaches to create biomaterials rely on reverse engineering of biological structures, on biomimicking, and on bioinspiration. Plant nanobionics is a recent approach to engineer new materials combining plant organelles with synthetic nanoparticles to enhance, for example, photosynthesis. Biological structures often outperform man-made materials. For example, higher plants sense temperature changes with high responsivity. However, these properties do not persist after cell death. Here, we permanently stabilize the temperature response of isolated plant cells adding carbon nanotubes (CNTs). Interconnecting cells, we create materials with an effective temperature coefficient of electrical resistance (TCR) of −1,730% K^(−1), ∼2 orders of magnitude higher than the best available sensors. This extreme temperature response is due to metal ions contained in the egg-box structure of the pectin backbone, lodged between cellulose microfibrils. The presence of a network of CNTs stabilizes the response of cells at high temperatures without decreasing the activation energy of the material. CNTs also increase the background conductivity, making these materials suitable elements for thermal and distance sensors.

Although molecular systematists may use the terminology of cladism, claiming that the reconstruction of phylogenetic relationships is based on shared derived states (synapomorphies), the latter is not the case. Rather, molecular systematics is (largely) based on the assumption, first clearly articulated by Zuckerkandl and Pauling (1962), that degree of overall similarity reflects degree of relatedness. This assumption derives from interpreting molecular similarity (or dissimilarity) between taxa in the context of a Darwinian model of continual and gradual change. Review of the history of molecular systematics and its claims in the context of molecular biology reveals that there is no basis for the “molecular assumption.”

During macrophage infection Candida albicans expresses differentially several genes whose functions are associated with its survival strategy. Among others, we have isolated CaGS gene, which is homologous to SNF3, a glucose sensor of Saccharomyces cerevisiae. To elucidate its potential role during infection, CaGS has been disrupted and the resulting phenotype analyzed on different solid media. The null mutant lost the ability to form hyphae on a medium with low glucose concentration and serum. Furthermore, this mutant does not disrupt macrophage in in vitro infections. We believe that this putative glucose sensor is involved in hyphal development during macrophage infection.

The ability of intracellular pathogens to cause infection is related to their capacity to survive and grow inside macrophages or in other cell types. Candida albicans latent virulence is likely to be related to a similar mechanism of avoiding killing by specialized cells and to the resulting ability to grow in such hostile environments. Using a differential display reverse transcription polymerase chain reaction technique, we have identified seven genes induced in C. albicans during macrophage phagocytosis. Sequence analyses and database searches revealed that these cDNAs coded for proteins homologous to yeast metabolic proteins. Interestingly, four of them are putative peroxisomal proteins, and two are involved in environmental signal sensing and transduction. Among the seven genes induced by C. albicans, six represent new information that were not described in other infection models.

The hydroxylamine derivative bimoclomol (BM) has been shown to activate natural cytoprotective homeostatic responses by enhancing the capability of cells to cope with various pathophysiological conditions. It exerts its effect in synergy with low levels of stress to induce the synthesis of members of major stress protein families. We show here that the presence of BM does not influence protein denaturation in the cells. BM and its derivatives selectively interact with acidic lipids and modulate their thermal and dynamic properties. BM acts as a membrane fluidizer at normal temperature, but it is a highly efficient membrane stabilizer, inhibiting the bilayer–nonbilayer phase transitions during severe heat shock. We suggest that BM and the related compounds modify those domains of membrane lipids where the thermally or chemically induced perturbation of lipid phase is sensed and transduced into a cellular signal, leading to enhanced activation of heat shock genes. BM may be a prototype for clinically safe membrane-interacting drug candidates that rebalance the level and composition of heat shock proteins.

Intravascular ultrasound is a catheter-based imaging modality that was developed to investigate the condition of coronary arteries and assess the vulnerability of coronary atherosclerotic plaques in particular. Since its introduction in the clinic 20 years ago, use of intravascular ultrasound innovation has been relatively limited. Intravascular ultrasound remains a niche technology; its clinical practice did not vastly expand, except in Japan, where intravascular ultrasound is an appraised tool for guiding percutaneous coronary interventions. In this qualitative research study, we follow scholarship on the sociology of innovation in exploring both the current adoption practices and perspectives on the future of intravascular ultrasound. We conducted a survey of biomedical experts with experience in the technology, the practice, and the commercialization of intravascular ultrasound. The collected information enabled us to map intravascular ultrasound controversies as well as to outline the dynamics of the international network of experts that generates intravascular ultrasound innovations and uses intravascular ultrasound technologies. While the technology is praised for its capacity to measure coronary atherosclerotic plaque morphology and is steadily used in clinical research, the lack of demonstrated benefits of intravascular ultrasound guided coronary interventions emerges as the strongest factor that prevents its expansion. Furthermore, most of the controversies identified were external to intravascular ultrasound technology itself, meaning that decision making at the industrial, financial and regulatory levels are likely to determine the future of intravascular ultrasound. In light of opinions from the responding experts', a wider adoption of intravascular ultrasound as a stand-alone imaging modality seems rather uncertain, but the appeal for this technology may be renewed by improving image quality and through combination with complementary imaging modalities.

Sciences Po Paris a accueilli les 15 et 16 janvier 2009 une conference sur les enjeux de la consommation durable, dont l’ambition etait d’explorer une notion qui connait un succes croissant et a laquelle se referent de nombreux groupes sociaux : decideurs publics, representants des activites economiques, associations de consommateurs ou militants de la cause environnementale, le plus souvent pour en souhaiter le developpement. La diffusion de la notion et, plus encore, son inscription en bonne place a l’agenda des politiques publiques appellent un travail de definition, double d’une reflexion sur les fondements de la consommation durable : quels domaines de la consommation concerne-t-elle ? Quels sont les leviers de son developpement ? De quelle conception des rapports entre consommateurs et producteurs est-elle porteuse ? Pour ce faire, les organisateurs de la conference, issus du Centre de sociologie des organisations (CSO, Sciences Po/CNRS), se sont attaches a situer la problematique de la consommation durable dans une double perspective : en tant que pratique individuelle, d’une part, en tant que probleme public, d’autre part1. Il s’agissait donc de ne pas limiter l’analyse du phenomene aux theories economiques de l’analyse des determinants de la consommation, pour en interroger les dimensions sociologiques et institutionnelles. La conference a reuni une quinzaine d’intervenants issus d’horizons disciplinaires divers (sociologie, sciences politiques, psychosociologie, economie, management du developpement durable...) pour instruire la question des enjeux de la consommation durable de differents points

We have characterized the promoter region of the delta9-desaturase gene from two different strains of the dimorphic fungus Histoplasma capsulatum. Desaturase transcription is regulated in the two phases of growth: it is transcribed in the yeast phase at 37 degrees C, while it is inactive in the mycelial phase at 25 degrees C. Phase transition can be induced by shifting the temperature from 25 to 37 degrees C or by adding cAMP to the growth medium. We have identified a stress-responsive cis element (STRE) responsive to cyclic AMP (cAMP)-signaling pathway and demonstrated that this element acts in H. capsulatum. We have also identified an element, hereafter called DRE (Desaturase Regulatory Element), present in the promoters of the H. capsulatum and S. cerevisiae delta9-desaturase gene. We show that this element is necessary but not sufficient to regulate transcription of the H. capsulatum delta9-desaturase gene.

Membranes provide the structural framework that divides cells from their environment and that, in eukaryotic cells, permits compartmentation. They are not simply passive barriers that are liable to be damaged during environmental challenge or pathological states, but are involved in cellular responses and in modulating intracellular signalling. Recent data show that the expression of several genes, particularly those that respond to changes in temperature, ageing or disease, is influenced and/or controlled by the membrane's physical state.

Establishment of infection and disease implies modifications in the genetic programmes of the cell systems that are involved and the differential expression of genes in both parasite and host. In order to identify and isolate relevant genes of the fungus, Histoplasma capsulatum , in which expression is specifically induced during its interaction with murine macrophages (Mф), we performed a comparative analysis of the pattern of gene expression of the fungus before and after exposure to, and internalization into Mф by using differential display reverse transcriptase-PCR (DDRT-PCR). Using a limited set of primer combinations, six cDNA fragments of H. capsulatum were identified and isolated; five representing fungal genes in which expressions were enhanced during Mф infection, whereas one mRNA fragment was down-regulated. Slot blots followed by Northern blot analyses confirmed that the transcripts detected with cDNA clones were over expressed after 1 h of Mф infection, whereas no transcripts were detected with mRNA purified from H. capsulatum before infection. Sequence analyses and database searches revealed no significant homology to any known sequence for five of these clones. One of the clones showed homology to the rat p105 kD protein, and to the p100 kD co-activator proteins of human and Caenorhabditis elegans . To our knowledge, this is the first experimental evidence that specific genes are differentially expressed by a fungal pathogen when it is exposed to, and phagocytosed by Mф. Furthermore, these results show that the DDRT-PCR procedure has adequate sensitivity to detect fungal genes induced during parasite–host interaction to identify potential new targets that can be used to develop new antifungal drugs.

Heat shock (HS) proteins (HSP) function as molecular chaperones and protect cells from thermal and oxidative injury. The signals leading to HSP synthesis, i.e. the “cellular thermometer(s),” are still a matter of debate. In the human premonocytic line U937, we investigated the effects of specific modification of membrane fatty acid (FA) composition by incubation with various saturated and unsaturated fatty acids (UFA) on the HS response and on hydrogen peroxide (H2O2)-induced cell death. FA readily incorporated into U937 cell membranes. UFA did not modulate the HS response but potentiated H2O2-mediated damage, while pre-exposure to HS protected the UFA-treated cells from this increased H2O2 toxicity.

The composition and physical state of membrane lipids determine the dynamic nature of membranes, which in turn, could directly be linked to the activity of various membrane-associated cellular functions. To better understand the molecular basis of different membrane-related phenomena we established a novel strategy to alter unsaturation of mammalian cell membranes with an identical genetic background. We transfected L929 mouse fibroblastoid cells with DNA constructs containing the Δ9-fatty acid desaturase gene (Ole1) ofS. cerevisiaeunder the control of desaturase promoters derived either from wild type or mutant strains of the dimorphic fungusH. capsulatum.

International audience; Terminal deoxynucletidyl transferase (TdT) is overexpressed in some cancer types, where it might compete with pol μ during the mutagenic repair of double strand breaks (DSBs) through the nonhomologous end joining (NHEJ) pathway. Here we report the discovery and characterization of pyrrolyl and indolyl diketo acids that specifically target TdT and behave as nucleotide-competitive inhibitors. These compounds show a selective toxicity toward MOLT-4 compared to HeLa cells that correlate well with in vitro selectivity for TdT. The binding site of two of these inhibitors was determined by cocrystallization with TdT, explaining why these compounds are competitive inhibitors of the deoxynucleotide triphosphate (dNTP). In addition, because of the observed dual localization of the phenyl substituent, these studies open the possibility of rationally designing more potent compounds.

OBJECTIVES: In this study we investigated the in vitro fungistatic and fungicidal activities of CPA18 and CPA109, two azole compounds with original structural features, alone and in combination with fluconazole against fluconazole-susceptible and -resistant Candida albicans strains. METHODS: Antifungal activities were measured by MIC evaluation and time-kill studies. Azole binding analysis was performed by UV-Vis spectroscopy. Hyphal growth inhibition and filipin and propidium iodide staining assays were used for morphological analysis. An analysis of membrane lipids was also performed to gauge alterations in membrane composition and integrity. Synergism was calculated using fractional inhibitory concentration indices (FICIs). Evaluation of cytotoxicity towards murine macrophages was performed to verify selective antifungal activity. RESULTS: Even though their binding affinity to C. albicans Erg11p is comparable to that of fluconazole, CPA compounds are active against resistant strains of C. albicans with a mutation in ERG11 sequences and/or overexpressing the ABC transporter genes CDR1 and CDR2, which encode ATP-dependent efflux pumps. Moreover, CPA18 is fungistatic, even against the two resistant strains, and was found to be synergistic with fluconazole. Differently from fluconazole and other related azoles, CPA compounds induced marked changes in membrane permeability and dramatic alterations in membrane lipid composition. CONCLUSIONS: Our outcomes suggest that CPA compounds are able to overcome major mechanisms of resistance in C. albicans. Also, they are promising candidates for combination treatment that could reduce the toxicity caused by high fluconazole doses, particularly in immunocompromised patients.

Here we present new materials obtained using, either fungal or isolated tobacco cells in association with different percentages of carbon nanotubes (CNTs). As a proof of concept, we used eitherCandida albicansor a non-green Tobacco BY-2 cell line combined with multi-walled CNTs. The electrical, mechanical, and conductivity vs temperature properties for some of these materials have been determined.C. albicans-based tissues have high conductivity and are stable at elevated temperatures. By lowering the CNTs content, we obtained a stable, electrically conductive optical transparent film, though with a relatively high sheet resistance. Further, we produced, using tobacco cells, a material that exhibits good electrical as well as mechanical properties.

New arylthioindole derivatives having different cyclic substituents at position 2 of the indole were synthesized as anticancer agents. Several compounds inhibited tubulin polymerization at submicromolar concentration and inhibited cell growth at low nanomolar concentrations. Compounds 18 and 57 were superior to the previously synthesized 5. Compound 18 was exceptionally potent as an inhibitor of cell growth: it showed IC50 = 1.0 nM in MCF-7 cells, and it was uniformly active in the whole panel of cancer cells and superior to colchicine and combretastatin A-4. Compounds 18, 20, 55, and 57 were notably more potent than vinorelbine, vinblastine, and paclitaxel in the NCI/ADR-RES and Messa/Dx5 cell lines, which overexpress P-glycoprotein. Compounds 18 and 57 showed initial vascular disrupting effects in a tumor model of liver rhabdomyosarcomas at 15 mg/kg intravenous dosage. Derivative 18 showed water solubility and higher metabolic stability than 5 in human liver microsomes.

Chionodraco hamatus and Trematomus bernacchii are perciforms, members of the fish suborder Notothenioidei that live in the Antarctic Ocean and experience very cold and persistent environmental temperature. These fish have biochemical and molecular features that allow them to live at these extreme cold temperatures. Fine tuning of the level of unsaturated fatty acids content in membrane is a key mechanism of living organisms to adapt to cold and high temperatures. Desaturases are key enzymes that synthesize unsaturated fatty acyl-CoAs from saturated fatty acids. We cloned and sequenced a Δ(9)-desaturase gene and its cDNA of C. hamatus, and the cDNA of T. bernacchii. The coded proteins are virtually identical and share homology to other Δ(9)-desaturase fish sequences. These proteins contain, in the first trans-membrane domain, two cysteine residues that may form a disulfur bond present in the corresponding membrane region of Δ(9)-desaturase proteins of other Antarctic fish but not in Eleginops maclovinus that experiences higher environmental temperatures and in all other Δ(9)-desaturase genes of mammals present in data bases. C. hamatus Δ(9)-desaturase gene complements a Saccharomyces cerevisiae mutant lacking Δ(9)-desaturase (Ole1) gene. Analysis of sequence homology of the trans-membrane domains of Δ(9)-desaturase and the cytoplasmic region of the same proteins of Antarctic fish, non-Antarctic fish and mammals suggest that the significant differences found in the homologous sequences of the first trans-membrane domain may be due to the specific lipid content of their membrane.