988 resultados para theatre studies


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The disintegration of the USSR brought the emergence of a new geo-energy space in Central Asia. This space arose in the context of a global energy transition, which began in the late 1970s. Therefore, this new space in a changing energy world requires both new conceptual frameworks of analysis and the creation of new analytical tools. Taking into account this fact, our paper attempts to apply the theoretical framework of the Global Commodity Chain (GCC) to the case of natural resources in Central Asia. The aim of the paper is to check if there could be any Central Asia’s geo-energy space, assuming that this space would exist if natural resources were managed with regional criteria. The paper is divided into four sections. First an introduction that describes the new global energy context within natural resources of Central Asia would be integrated. Secondly, the paper justifies why the GCC methodology is suitable for the study of the value chains of energy products. Thirdly, we build up three cases studies (oil and uranium from Kazakhstan and gas from Turkmenistan) which reveal a high degree of uncertainty over the direction these chains will take. Finally, we present the conclusions of this study that state that the most plausible scenario would be the integration of energy resources of these countries in GCC where the core of the decision-making process will be far away from the region of Central Asia. Key words: Energy transition, geo-energy space, Global Commodity Chains, Central Asia

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This paper presents, from the perspective of technological development and production, the results of an investigation examining 61 clinical studies with vaccines conducted in Brazil between 1938-2013, with the participation of the Oswaldo Cruz Institute (IOC) and the Oswaldo Cruz Foundation (Fiocruz). These studies have been identified and reviewed according to criteria, such as the kind of vaccine (viral, bacterial, parasitic), their rationale, design and methodological strategies. The results indicate that IOC and Fiocruz have accumulated along this time significant knowledge and experience for the performance of studies in all clinical phases and are prepared for the development of new vaccines products and processes. We recommend national policy strategies to overcome existing regulatory and financing constraints.

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Malaria is responsible for more deaths around the world than any other parasitic disease. Due to the emergence of strains that are resistant to the current chemotherapeutic antimalarial arsenal, the search for new antimalarial drugs remains urgent though hampered by a lack of knowledge regarding the molecular mechanisms of artemisinin resistance. Semisynthetic compounds derived from diterpenes from the medicinal plant Wedelia paludosawere tested in silico against the Plasmodium falciparumCa2+-ATPase, PfATP6. This protein was constructed by comparative modelling using the three-dimensional structure of a homologous protein, 1IWO, as a scaffold. Compound 21 showed the best docking scores, indicating a better interaction with PfATP6 than that of thapsigargin, the natural inhibitor. Inhibition of PfATP6 by diterpene compounds could promote a change in calcium homeostasis, leading to parasite death. These data suggest PfATP6 as a potential target for the antimalarial ent-kaurane diterpenes.

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Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and cytotoxic properties have been attributed to the presence of the nitro group. However, we synthesised nitroimidazoles with activity against the trypomastigotes of Trypanosoma cruzi, but that were not genotoxic. Herein, nitroimidazoles (11-19) bearing different substituent groups were investigated for their potential induction of genotoxicity (comet assay) and mutagenicity (Salmonella/Microsome assay) and the correlations of these effects with their trypanocidal effect and with megazol were investigated. The compounds were designed to analyse the role played by the position of the nitro group in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable groups at N-1 as an anion receptor group and the role of a methyl group at C-2. Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to those bearing NO2 at C-5. However, when there was a CH3 at C-2, the position of the NO2 group had no influence on the genotoxic activity. Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3 at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl) and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on genotoxicity. This study contributes to the future search for new and safer prototypes and provide.

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Several species of Aspidosperma plants are used to treat diseases in the tropics, including Aspidosperma ramiflorum, which acts against leishmaniasis, an activity that is experimentally confirmed. The species, known as guatambu-yellow, yellowperoba, coffee-peroba andmatiambu, grows in the Atlantic Forest of Brazil in the South to the Southeast regions. Through a guided biofractionation of A. ramiflorum extracts, the plant activity against Plasmodium falciparum was evaluated in vitro for toxicity towards human hepatoma G2 cells, normal monkey kidney cells and nonimmortalised human monocytes isolated from peripheral blood. Six of the seven extracts tested were active at low doses (half-maximal drug inhibitory concentration < 3.8 µg/mL); the aqueous extract was inactive. Overall, the plant extracts and the purified compounds displayed low toxicity in vitro. A nonsoluble extract fraction and one purified alkaloid isositsirikine (compound 5) displayed high selectivity indexes (SI) (= 56 and 113, respectively), whereas compounds 2 and 3 were toxic (SI < 10). The structure, activity and low toxicity of isositsirikine in vitro are described here for the first time in A. ramiflorum, but only the neutral and precipitate plant fractions were tested for activity, which caused up to 53% parasitaemia inhibition of Plasmodium bergheiin mice with blood-induced malaria. This plant species is likely to be useful in the further development of an antimalarial drug, but its pharmacological evaluation is still required.

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Diabetes is a growing epidemic with devastating human, social and economic impact. It is associated with significant changes in plasma concentrations of lipoproteins. We tested the hypothesis that lipoproteins modulate the function and survival of insulin-secreting cells. We first detected the presence of several receptors that participate in the binding and processing of plasma lipoproteins and confirmed the internalization of fluorescent LDL and HDL particles in insulin-secreting β-cells. Purified human VLDL and LDL particles reduced insulin mRNA levels and β-cell proliferation, and induced a dose-dependent increase in the rate of apoptosis. In mice lacking the LDL receptor, islets showed a dramatic decrease in LDL uptake and were partially resistant to apoptosis caused by LDL. VLDL-induced apoptosis of β-cells involved caspase-3 cleavage and reduction in levels of the c-Jun N-terminal (JNK) Interacting Protein-1 (IB1/JIP-1). In contrast, the pro-apoptotic signaling of lipoproteins was antagonized by HDL particles or by a small peptide inhibitor of JNK. The protective effects of HDL were mediated, in part, by inhibition of caspase-3 cleavage and activation of the protein kinase Akt/PKB. Heart disease is a major cause of morbidity and mortality among patients with diabetes. When heart failure is refractory to medical therapy and cannot be improved by electrical resynchronization, percutaneous angioplasty or coronary graft bypass surgery, heart transplantation remains a "last resort" therapy. Nevertheless, it is limited by the side effects of immunosuppressive drugs and chronic rejection. Localized expression of immunomodulatory genes in the donor organ can create a state of immune privilege within the graft, and was performed in rodent hearts by infecting cells with an adenovirus encoding indoleamine 2,3-dioxygenase (IDO), the rate-limiting enzyme in the catabolism of tryptophane. Other strategies are based on genetic manipulation of dendritic cells (DCs) with immunosuppressive genes and in vitro exposure of DCs to agents that prevent their maturation by inflammatory cytokines. Finally, we used 5-bromo-2'-deoxyuridine, which is incorporated into DNA and diluted with cell division, to identify long-term label retaining cells in the adult rodent heart. The majority of these cells were positive for the stem cell antigen-1 (Sca-1) and negative for the endothelial precursor marker CD31. They formed cardiospheres in vitro and showed differentiation potential into mesenchymal cell lineages. When cultured in cardiomyogenic differentiation medium, they expressed cardiac-specific genes. Taken together, these data provide evidence of slow-cycling stem cells in the rodent heart. Chronic shortage of donor organs opens the way to cardiac stem cell therapy in humans, although the long way from animal experimentation to routine therapy in patients may still take several years. - Du diabète de type 2 à la maladie coronarienne : trois études sur les dysfonctions de la cellule sécrétrice d'insuline induites par les dyslipidémies, l'immunomodulation dans la transplantation cardiaque, et la thérapie par des cellules souches myocardiques. Le diabète de type 2 a pris les dimensions d'une épidémie, avec des conséquences sociales et économiques dont nous n'avons pas encore pris toute la mesure. La maladie s'accompagne souvent d'une dyslipidémie caractérisée par une hypertriglycéridémie, des taux abaissés de cholestérol HDL, et des concentrations de cholestérol LDL à la limite supérieure de ce qui est considéré comme acceptable. L'hypothèse à la base de cette étude est qu'une modification des taux plasmatiques de lipoprotéines pourrait avoir une influence directe sur la cellule β sécrétrice d'insuline en modifiant sa fonction, sa durée de vie et son taux de régénération. Dans un premier temps, nous avons mis en évidence, sur la cellule β, la présence de plusieurs récepteurs impliqués dans la captation des lipoprotéines. Nous avons confirmé la fonctionnalité de ces récepteurs en suivant l'internalisation de LDL et de HDL marqués. En présence de VLDL ou de LDL humains, nous avons observé une diminution de la transcription du gène de l'insuline, une prolifération cellulaire réduite, et une augmentation de l'apoptose, toutes fonctions de la dose et du temps d'exposition. L'apoptose induite par les VLDL passe par une activation de la caspase-3 et une réduction du taux de la protéine IB1/JIP-1 (Islet Brain1/JNK Interacting Protein 1), dont une mutation est associée à une forme monogénique de diabète de type 2. Par opposition, les HDL, ainsi que des peptides inhibiteurs de JNK, sont capables de contrer la cascade pro-apoptotique déclenchée, respectivement, par les LDL et les VLDL. Ces effets protecteurs comprennent l'inhibition du clivage de la caspase-3 et l'activation de la protéine kinase Akt/PKB. En conclusion, les lipoprotéines sont des éléments clés de la survie de la cellule β, et pourraient contribuer au dysfonctionnement observé dans le pancréas endocrine au cours du développement du diabète. La maladie cardiaque, et plus particulièrement la maladie coronarienne, est une cause majeure de morbidité et de mortalité chez les patients atteints de diabète. Plusieurs stratégies sont utilisées quotidiennement pour pallier les atteintes cardiaques: traitements médicamenteux, électromécaniques par resynchronisation électrique, ou communément appelés « interventionnels » lorsqu'ils font appel à l'angioplastie percutanée. La revascularisation du myocarde par des pontages coronariens donne également de très bons résultats dans certaines situations. Il existe toutefois des cas où plus aucune de ces approches n'est suffisante. La transplantation cardiaque est alors la thérapie de choix pour un nombre restreint de patients. La thérapie génique, en permettant l'expression locale de gènes immunomodulateurs dans l'organe greffé, permet de diminuer les réactions de rejet inhérentes à toute transplantation (à l'exception de celles réalisées entre deux jumeaux homozygotes). Nous avons appliqué chez des rongeurs cette stratégie en infectant le coeur greffé avec un adénovirus codant pour l'enzyme indoleamine 2,3-dioxygénase (IDO), une enzyme clé dans le catabolisme du tryptophane. Nous avons procédé de manière identique in vitro en surexprimant IDO dans les cellules dendritiques, dont le rôle est de présenter les antigènes aux lymphocytes Τ du receveur. Des expériences similaires ont été réalisées en traitant les cellules dendritiques avec des substances capables de prévenir, en partie du moins, leur maturation par des agents pro-inflammatoires. Finalement, nous avons exploré une stratégie utilisée couramment en hématologie, mais qui n'en est encore qu'à ses débuts au niveau cardiaque : la thérapie par des cellules souches. En traitant des rongeurs avec un marqueur qui s'incorpore dans l'ADN nucléaire, le 5-bromo- 2'-deoxyuridine, nous avons identifié une population cellulaire se divisant rarement, positive en grande partie pour l'antigène embryonnaire Sca-1 et négative pour le marqueur endothélial CD31. En culture, ces cellules forment des cardiosphères et sont capables de se différencier dans les principaux types tissulaires mésenchymateux. Dans un milieu de differentiation adéquat, ces cellules expriment des gènes cardiomyocytaires. En résumé, ces données confirment la présence chez le rongeur d'une population résidente de précurseurs myocardiques. En addenda, on trouvera deux publications relatives à la cellule β productrice d'insuline. Le premier article démontre le rôle essentiel joué par la complexine dans l'insulino-sécrétion, tandis que le second souligne l'importance de la protéine IB1/JIP-1 dans la protection contre l'apoptose de la cellule β induite par certaines cytokines.

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To date, 21 species of the genus Angiostrongylus (Nematoda: Angiostrongylidae) have been reported around the world, 15 of which are parasites of rodents. In this study, new host, geographic records, and histopathologic studies of Angiostrongylus spp in sigmodontine rodents from Argentina, with an updated summary of records from rodent hosts and host specificity assessment, are provided. Records of Angiostrongylus costaricensis from Akodon montensis andAngiostrongylus morerai from six new hosts and geographical localities in Argentina are reported. The gross and histopathologic changes in the lungs of the host species due to angiostrongylosis are described. Published records of the genus Angiostrongylus from rodents and patterns of host specificity are presented. Individual Angiostrongylusspecies parasitise between one-19 different host species. The most frequent values of the specificity index (STD) were between 1-5.97. The elevated number of host species (n = 7) of A. morerai with a STD = 1.86 is a reflection of multiple systematic studies of parasites from sigmodontine rodents in the area of Cuenca del Plata, Argentina, showing that an increase in sampling effort can result in new findings. The combination of low host specificity and a wide geographic distribution of Angiostrongylus spp indicates a troubling epidemiological scenario although, as yet, no human cases have been reported.

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Geochemical data that is derived from the whole or partial analysis of various geologic materialsrepresent a composition of mineralogies or solute species. Minerals are composed of structuredrelationships between cations and anions which, through atomic and molecular forces, keep the elementsbound in specific configurations. The chemical compositions of minerals have specific relationships thatare governed by these molecular controls. In the case of olivine, there is a well-defined relationshipbetween Mn-Fe-Mg with Si. Balances between the principal elements defining olivine composition andother significant constituents in the composition (Al, Ti) have been defined, resulting in a near-linearrelationship between the logarithmic relative proportion of Si versus (MgMnFe) and Mg versus (MnFe),which is typically described but poorly illustrated in the simplex.The present contribution corresponds to ongoing research, which attempts to relate stoichiometry andgeochemical data using compositional geometry. We describe here the approach by which stoichiometricrelationships based on mineralogical constraints can be accounted for in the space of simplicialcoordinates using olivines as an example. Further examples for other mineral types (plagioclases andmore complex minerals such as clays) are needed. Issues that remain to be dealt with include thereduction of a bulk chemical composition of a rock comprised of several minerals from which appropriatebalances can be used to describe the composition in a realistic mineralogical framework. The overallobjective of our research is to answer the question: In the cases where the mineralogy is unknown, arethere suitable proxies that can be substituted?Kew words: Aitchison geometry, balances, mineral composition, oxides

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Tectonic observations in the Tethyan Himalaya reveal an important extensional event that succeeds the emplacement of SW-verging nappes. A major thrust, called the Kum Tso Thrust, has been backfolded and reactivated by normal faulting associated with this event. Measurements of the Kubler index, coupled with characterization of clay-size paragenesis show the effect of normal faulting on the regional metamorphic zonation and indicate that important extension zones, like the Sarchu-Lachung La Normal Fault Zone (SLFZ), exist within the Tethyan Himalaya. Diagenetic limestones from within the SLFZ are characterized by the occurrence of mixed-layered clay phases, kaolinite and an illite with a 001 peak >0.4 Delta degrees2 theta. This zone is bordered by two anchizonal-to-epizonal zones, where illite peaks become narrower. Further to the NE the successive appearance of biotite, chloritoid, garnet and garnet-staurolite-kyanite assemblapes testifies to an increase in metamorphic grade. The cataclastic samples from the normal faults contain kaolinite, smectite and a `broad' illite, indicating that extension occurs under diagenetic conditions.

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The biodistribution of the 202 monoclonal antibody against CEA labeled with 88Y by the bicyclic DTPA anhydride method was studied in normal Balb/c mice. The in vitro binding to 1 X 10(7) CO112, LS174T and WiDR colon cancer cells was 21.0, 27.3 and 18.8%, respectively. The binding to an equal number of KM-3 leukemia cells and normal human lymphocytes was 8.9 and 3.2%, respectively. Liver, spleen, kidney and blood were the tissues that showed the highest uptake of radiolabeled antibody in vivo.