988 resultados para Open mixed cultures


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This paper provides a new benchmark for the analysis of the international diversi…cation puzzle in a tractable new open economy macroeconomic model. Building on Cole and Obstfeld (1991) and Heathcote and Perri (2009), this model speci…es an equilibrium model of perfect risk sharing in incomplete markets, with endogenous portfolios and number of varieties. Equity home bias may not be a puzzle but a perfectly optimal allocation for hedging risk. In contrast to previous work, the model shows that: (i) optimal international portfolio diversi…cation is driven by home bias in capital goods, independently of home bias in consumption, and by the share of income accruing to labour. The model explains reasonably well the recent patterns of portfolio allocations in developed economies; and (ii) optimal portfolio shares are independent of market dynamics.

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Aggregating fetal liver cell cultures were tested for their ability to metabolize xenobiotics using ethoxycoumarin-O-deethylase (ECOD), as marker of phase I metabolism, and glutathione S-transferase (GST), as marker for phase II reactions. Significant basal activities, stable over 14 days in culture were measured for both ECOD and GST activities. The prototype cytochrome P450 inducers, 3-methylcholanthrene (3-MC) and phenobarbital (PB), increased ECOD and GST activities reaching an optimum 7 days after culturing, followed by a decline in activity. This decline was partially prevented by 1% dimethyl sulfoxide (DMSO) added chronically to the culture medium. DMSO was also found to induce ECOD activity and to a lesser extent GST activity. Furthermore, it potentiated in a dose-dependent manner the induction of ECOD by PB. The food-borne carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is metabolically transformed through a number of pathways in vivo. It was therefore used to examine the metabolic capacity in fetal and adult liver cell aggregates. Metabolism of MeIQx was mainly through N2-conjugation, resulting in formation of the N2-glucuronide and sulfamate conjugates for non-induced fetal liver cells. These metabolites were also found in large amounts in non-induced adult liver cells. Low levels of cytochrome P450-mediated ring-hydroxylated metabolites were detected in both non-induced fetal and adult liver cells. After induction with arochlor (PCB) or 3-MC, the major pathway was ring-hydroxylation (cytochrome P450 dependent), followed by conjugation to beta-glucuronic or sulfuric acid. The presence of the glucuronide conjugate of N-hydroxy-MeIQx, a mutagenic metabolite, suggested an induction of P450 CYP1A2. The metabolism of MeIQx by liver cell aggregates is very similar to that observed in vivo and suggests that aggregating liver cell cultures are a useful model for in vitro metabolic studies in toxicology.

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During brain development, spontaneous neuronal activity has been shown to play a crucial role in the maturation of neuronal circuitries. Activity-related signals may cause selective neuronal cell death and/or rearrangement of neuronal connectivity. To study the effects of sustained inhibitory activity on developing inhibitory (GABAergic) neurons, three-dimensional primary cell cultures of fetal rat telencephalon were used. In relatively immature cultures, muscimol (10 microns), a GABAA receptor agonist, induced a transient increase in apoptotic cell death, as evidenced by a cycloheximide-sensitive increase of free nucleosomes and an increased frequency of DNA double strand breaks (TUNEL labeling). Furthermore, muscimol caused an irreversible reduction of glutamic acid decarboxylase activity, indicating a loss of GABAergic neurons. The muscimol-induced death of GABAergic neurons was attenuated by the GABAA receptor blockers bicuculline (100 microns) and picrotoxin (100 microns), by depolarizing potassium concentrations (30 mM KCl) and by the L-type calcium channel activator BAY K8644 (2 microns). As compared to the cholinergic marker (choline acetyltransferase activity), glutamic acid decarboxylase activity was significantly more affected by various agents known to inhibit neuronal activity, including tetrodotoxin (1 micron), flunarizine (5 microns), MK 801 (50 microns) and propofol (40 microns). The present results suggest that the survival of a subpopulation of immature GABAergic neurons is dependent on sustained neuronal activity and that these neurons may undergo apoptotic cell death in response to GABAA autoreceptor activation.

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L'exposition aux bioaérosols (endotoxines, bactéries et spores de champignons en suspension dans l'air) et les problèmes de santé qui en découlent sont bien connus dans certains milieux professionnels (station d'épuration des eaux usées, élevages d'animaux, traitements des déchets organiques, travailleurs du bois, récolte et manutention des céréales, agriculture...). Cependant, les études avec investigations des concentrations aéroportées d'endotoxines et de micro-organismes se font très rares dans d'autres milieux professionnels à risque. Cette note d'actualité scientifique présente la synthèse de deux publications visant à quantifier les bioaérosols dans deux milieux professionnels rarement étudiés : les cabinets dentaires et les cultures maraîchères de concombres et tomates. Les dentistes ainsi que leurs assistants sont souvent bien informés sur les risques chimiques, les risques liés aux postures et les risques d'accidents avec exposition au sang. En revanche, le risque infectieux lié à une exposition aux bioaérosols est la plupart du temps méconnu. La flore bactérienne buccale est très riche et l'utilisation d'instruments tels que la fraise, le détartreur à ultrasons et le pistolet air-eau entraîne la dissémination aéroportée d'une grande quantité de bactéries. De plus, la conception des instruments générant un jet d'eau (diamètre des tubulures) favorise la formation de biofilm propice à l'adhérence et à la multiplication de micro-organismes à l'intérieur même des tuyaux. Ces micro-organismes se retrouvent alors en suspension dans l'air lors de l'utilisation de ces pistolets.L'inhalation de grandes quantités de ces micro-organismes pourrait alors engendrer des problèmes respiratoires (hypersensibilisation, asthme). De plus la présence de pathogènes, tels que les légionelles, les pseudomonas et les mycobactéries à croissance rapide, dans l'eau de ces unités dentaires peut aussi entraîner des risques infectieux pour les patients et pour les soignants. La production de tomates et concombres en Europe en 2008, était respectivement de 17 et 2 millions de tonnes dont 850 000 et 140 000 tonnes pour la France. La récolte, le tri et la mise en cageots ou en barquette individuelle de ces légumes génèrent de la poussière riche en matières organiques. Très peu d'études ont investigué l'exposition à ces poussières et aux endotoxines dans les serres de cultures intensives. Notamment, les données concernant les cultures de tomates sont inexistantes bien que ce légume soit un des plus cultivés en Europe. [Auteur]

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IPH responded to the Department of Justice, Equality and Defence review of the voluntary Code of Practice for the display and sale of alcohol in supermarkets, convenience stores and similar mixed trading outlets. The voluntary Code was introduced in 2008 as an alternative to the statutory rules for structural separation of alcohol products in mixed trading outlets which are set out in section 9 of the Intoxicating Liquor Act 2008. Interested bodies and individuals were invited to submit comments on the Compliance Report for 2011 and on the effectiveness of the voluntary approach to structural separation by 20th December 2011. The Minister said he intended to also seek the views of the Minister for Health and the Joint Oireachtas Committee on Justice, Defence and Equality before reaching any decision on whether to bring the statutory rules in the 2008 Act into operation.

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This document states the Institute of Public Health in Ireland’s (IPH) commitment to an Open Access policy and outlines how it implements that policy. "Open Access is the immediate, online, free availability of research outputs without restrictions on use commonly imposed by publisher copyright agreements. Open Access includes the outputs that scholars normally give away for free for publication; it includes peer-reviewed journal articles, conference papers and data of various kinds."1 The Open Access (OA) movement aims to: Provide access to scientific outputs in publications that are freely available Foster the adoption of open access publication models

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Infection of non-adherent TG180 murine sarcoma cells with Toxoplasma gondii was compared, at the ultrastructural level, in both in vivo and in vitro conditions. Suspensions of 3.0 x 10(6) TG180 cells infected in vitro with 1.0 x 10(6) parasites of the RH strain were harvested between the first and 6th day post-infection and processed for transmission electron microscopy. In vivo infection was made by intraperitoneal inoculation in mice of 1.0 x 10(6) TG180 cells, that were co-inoculated with a parasite suspension at the same cell concentration. Cells were harvested 10, 20, 30 min and 24, 48 h post-inoculation and processed for transmission electron microscopy at the same conditions of the in vitro culture. It was observed TG180 murine sarcoma cells with intense and equivalent intracellular parasitism in both conditions. Host cells with parasitophorous vacuoles containing up to 16 parasites, as well as parasites undergoing mitoses or presenting a bradyzoite-like morphology, were frequently seen in both culture methods.

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L’ETC-LUSI ha modificat l’aplicació de publicació de les metadades al portal de GeoNetwork amb l’objectiu de presentar i millorar la publicació de les mateixes, adaptant-se a la nova tipologia d’arxius d’emmagatzematge de les darreres versions del software de la casa ESRI, així com poder-les fer arribar al major nombre d’usuaris possible interessats en el intercanvi d’informació cartogràfica

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Aggregating cell cultures prepared from fetal rat telencephalon express the two subunits [cerebellar soluble lectins (CSL) 1 and 2] of a soluble, mannose-specific endogenous lectin (CSL) in a development-dependent manner. Increased CSL synthesis was found at an early postmitotic stage as well as during the period of maximal myelination. Repetitive treatment of early cultures with epidermal growth factor (EGF, 3nM) caused a great stimulation of CSL biosynthesis. Immunocytochemical studies revealed particularly intense CSL-specific staining in small, EGF-responsive cells, presumably glial cells. Large quantities of CSL-immunoreactive material were found also in the extracellular space and on the external side of the plasma membrane, indicating abundant release of CSL. The present findings suggest that EGF or EGF-related factors in the brain are able to regulate the expression of an endogenous lectin, affecting brain ontogeny.

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iii. Catheter-related bloodstream infection (CR-BSI) diagnosis usually involves catheter withdrawal. An alternative method for CR-BSI diagnosis is the differential time to positivity (DTP) between peripheral and catheter hub blood cultures. This study aims to validate the DTP method in short-term catheters. The results show a low prevalence of CR-BSI in the sample (8.4%). The DTP method is a valid alternative for CR-BSI diagnosis in those cases with monomicrobial cultures (80% sensitivity, 99% specificity, 92% positive predictive value, and 98% negative predictive value) and a cut-off point of 17.7 hours for positivity of hub blood culture may assess in CR-BSI diagnosis.

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Après la révolution religieuse des années 60, une nouvelle religiosité est-elle née ? Cette question est au coeur du livre. Il met, en effet, en scène les jeunes des années 80, les filles et les fils de la génération d'après-guerre, celle de Mai 68. Les parents ont pris leurs distances avec les différentes formes institutionnelles de l'autorité, y compris celle des Églises. Ils avaient été laissés libres de s'initier à une voie « spirituelle » : liberté de conscience et autonomie individuelle, deux valeurs clés attachées à la génération d'après-guerre, avaient orienté leur démarche religieuse. Les années 80 constituent de plus un contexte spécifique. Derrière le rideau de l'abondance, les contours de la précarité se dessinent. L'effondrement du mur de Berlin a entraîné celui des certitudes et des points de repère. L'apparition du sida a mis en cause le mythe dominant d'une jeunesse presque éternelle ouvrant sur une société sans âge et sans conflits de génération. Ces événements ont infléchi les quêtes de sens contemporaines. Fruit de la collaboration de vingt-deux sociologues venant de différents pays de l'Union européenne et de la Suisse, l'ouvrage, plutôt que de mettre côte à côte des observations empruntées aux pays concernés, propose des analyses transversales. Il permet ainsi de se faire une idée du changement religieux qui touche l'Europe dans son ensemble et de dégager quelques enjeux communs suscités par l'incertitude ambiante. Partant de l'analyse de la condition des jeunes dans les années 80, l'ouvrage aborde tour à tour la question de leur identité religieuse, celle de leurs systèmes de croyance, puis s'attarde sur les institutions qui ont contribué à leur socialisation religieuse. L'expérience constitue une caractéristique de la vie religieuse contemporaine, alors que la pluralité de l'offre reflète le changement socioculturel. Un chapitre est ainsi consacré à la présentation de quelques trajectoires typiques illustrant la gestion de l'incertitude dans laquelle est plongée la génération en cause. Enfin est abordée la question posée par une jeunesse qui apparaît aujourd'hui dépourvue d'encadrement institutionnel dans le champ religieux comme dans d'autres domaines : cette situation ne traduit-elle pas la crise de reproduction des institutions elles-mêmes ?

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Because of the limited accessibility of the brain for experimentation, but also for ethical and economical reasons, there is considerable interest in culture models suitable for neurotoxicological research. Although it is generally accepted that in vitro models cannot cover the entire spectrum of brain functions, they have proven to be indispensable for investigations in the life sciences since the early work of Harrison (1). To date, many in vitro models of various complexity are available, ranging from monolayer cultures of immortalized cell lines to organotypic cultures. Each of these culture systems has its particularities, therefore, it is of great importance to select the model that is most appropriate for the question to be solved.

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As part of the ACuteTox project aimed at the development of non-animal testing strategies for predicting human acute oral toxicity, aggregating brain cell cultures (AGGR) were examined for their capability to detect organ-specific toxicity. Previous multicenter evaluations of in vitro cytotoxicity showed that some 20% of the tested chemicals exhibited significantly lower in vitro toxicity as expected from in vivo toxicity data. This was supposed to be due to toxicity at supracellular (organ or system) levels. To examine the capability of AGGR to alert for potential organ-specific toxicants, concentration-response studies were carried out in AGGR for 86 chemicals, taking as endpoints the mRNA expression levels of four selected genes. The lowest observed effect concentration (LOEC) determined for each chemical was compared with the IC20 reported for the 3T3/NRU cytotoxicity assay. A LOEC lower than IC20 by at least a factor of 5 was taken to alert for organ-specific toxicity. The results showed that the frequency of alerts increased with the level of toxicity observed in AGGR. Among the chemicals identified as alert were many compounds known for their organ-specific toxicity. These findings suggest that AGGR are suitable for the detection of organ-specific toxicity and that they could, in conjunction with the 3T3/NRU cytotoxicity assay, improve the predictive capacity of in vitro toxicity testing.

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La sospita de bacterièmia relacionada a catèter (BRC) necessita la retirada d’aquest, confirmant-se a posteriori només en un 15-25%. La diferencia en el temps de positivització d´ hemocultius (DTP) ha demostrat ser un mètode fiable per el diagnòstic de BRC evitant la retirada del catèter. Amb la intenció de comprovar la utilitat clínica de la DTP, l’hem comparada amb un mètode diagnòstic estàndard. Hem inclòs 133 pacients ingressats a una unitat de cures intensives portadors de catèters venosos centrals. 56 pacients s’han aleatoritzats. No hem trobat diferències significatives en quant a morbi-mortalitat en els 2 grups havent evitat 70% de retirada innecessària de catèters en el grup de DTP.