943 resultados para 730102 Immune system and allergy


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One of the main features of the Greek currency are the big differences between emissions of the polis, which did not match either in their iconographic message types, not even in the met-rical pattern of their values. These differences were reflected in exchange systems ruled by the main sanctuaries that shrines stipu-lated thus giving official status to change.

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The ecophysiological effects of stress in female Persian sturgeon, Acipenser persicus brood fishes during catch, transport and their confinement in the Kurenski ponds at the Shahid Dr. Beheshti Fish Propagation and Rearing Center were studied. The brood fishes under study were caught at three catch stations located at the Sefidrud River, Sefidrud River estuary and Gorganrud River estuary and were held in ponds at the Shahid Marjani Fish Propagation and Rearing Center.

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This paper focuses on teaching boys, male teachers and the question of gendered pedagogies in neoliberal and postfeminist times of the proliferation of new forms of capitalism, multi-mediated technologies and the influence of globalization. It illustrates how a politics of re-masculinization and its reconstitution needs to be understood as set against changing economic and social conditions in which gender equity comes to be re-focused on boys as the ‚new disadvantaged‘. This re-framing of gender equity, it is argued, has been fuelled by both a media-inspired backlash discourse about ‚failing boys‘ and a neo-positivist emphasis on numbers derived primarily from standardized testing regimes at both global and national levels. A media-focused analysis of the proliferation of discourses about ‚failing boys‘ vis-a-vis the problem of encroaching feminization in the school system is provided to illuminate how certain truths about the influence of male teachers come to define how the terms of ensuring gender equity are delimited and reduced to a question of gendered pedagogies as grounded in sexed bodies. Historical accounts of the feminization of teaching in the North American context are also provided as a basis for building a more informed understanding of the present, particularly as it relates to the contextualization of policy articulation and enactment regarding the problem of teaching boys. In light of such historically informed and critical media analysis, it is argued that what is needed is a more informed, evidenced based policy articulation of the problem of teaching boys and a more gender sensitive reflection on the politics of masculinities in postfeminist times. (DIPF/Orig.)

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W HILE Hyderabad State developed from the Mughal subah, or province, of the Deccan, it did not represent a mere continuation of the Mughal provincial administration. By the end of the eighteenth century, Hyderabad represented a new political system, with a whole new set of participants. This article investigates the development of this political system and the constitution of its ruling class.

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Studies of chemokine receptors (CKR) in natural killer- (NK-) cells have already been published, but only a few gave detailed information on its differential expression on blood NK-cell subsets. We report on the expression of the inflammatory and homeostatic CKR on normal blood CD56(+low) CD16(+) and CD56(+high)  CD16(-/+low) NK-cells. Conventional CD56(+low) and CD56(+high) NK-cells present in the normal PB do express CKR for inflammatory cytokines, although with different patterns CD56(+low) NK-cells are mainly CXCR1/CXCR2(+) and CXCR3/CCR5(-/+), whereas mostly CD56(+high) NK-cells are CXCR1/CXCR2(-) and CXCR3/CCR5(+). Both NK-cell subsets have variable CXCR4 expression and are CCR4(-) and CCR6(-). The CKR repertoire of the CD56(+low) NK-cells approaches to that of neutrophils, whereas the CKR repertoire of the CD56(+high) NK-cells mimics that of Th1(+) T cells, suggesting that these cells are prepared to migrate into inflamed tissues at different phases of the immune response. In addition, we describe a subpopulation of NK-cells with intermediate levels of CD56 expression, which we named CD56(+int) NK-cells. These NK-cells are CXCR3/CCR5(+), they have intermediate levels of expression of CD16, CD62L, CD94, and CD122, and they are CD57(-) and CD158a(-). In view of their phenotypic features, we hypothesize that they correspond to a transitional stage, between the well-known CD56(+high) and CD56(+low) NK-cells populations.

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Numerous components of the Arctic freshwater system (atmosphere, ocean, cryosphere, terrestrial hydrology) have experienced large changes over the past few decades, and these changes are projected to amplify further in the future. Observations are particularly sparse, both in time and space, in the Polar Regions. Hence, modeling systems have been widely used and are a powerful tool to gain understanding on the functioning of the Arctic freshwater system and its integration within the global Earth system and climate. Here, we present a review of modeling studies addressing some aspect of the Arctic freshwater system. Through illustrative examples, we point out the value of using a hierarchy of models with increasing complexity and component interactions, in order to dismantle the important processes at play for the variability and changes of the different components of the Arctic freshwater system and the interplay between them. We discuss past and projected changes for the Arctic freshwater system and explore the sources of uncertainty associated with these model results. We further elaborate on some missing processes that should be included in future generations of Earth system models and highlight the importance of better quantification and understanding of natural variability, amongst other factors, for improved predictions of Arctic freshwater system change.

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Aging process is conceived as a normal stage during human life cycle, but it is also considered a hot topic among scientists and medical community. Alarming rates of premature aging and oxidative stress-related diseases have increasingly affect human individuals. Stress, pollution and exposition to chemical substances are considered the main triggering factors for those conditions; in addition, they also suppress the immune system and, therefore, improve organic vulnerability and occurrence of opportunistic infections [I]. Apart from the associated morbidity and mortality, the increasing rates of antimicrobial resistance improve the severity of the clinical conditions [2]. Botanical preparations possess a multitude of bioactive properties, namely acting as antimicrobials, antioxidants, and homeostasis modulators. Thus, upcoming alternatives, mainly based in plant phytochemicals, are necessary to improve the wellbeing as also life expectancy of individuals. The present study aims to evaluate and to compare both antioxidant and antimicrobial properties of plant extracts rich in phenolic compounds. Among the tested plants, Glycyrrhiza glabra L. (licorice) evidenced the most pronounced free radicals scavenging and antimicrobial effects, followed by Salvia officina/is L. (sage), Thymus vulgaris L. (thyme) and Origanum vulgare L. (oregano). Eucalyptus globulus Labill. (blue gum) and Juglans regia L. (walnut) also showed a high effect, while Pterospartum tridentatum (L.) Willk. (carqueja) and Rubus ulmifolius Schott (elm leaf blackberry) displayed moderate effects, and lastly, Tabebuia impetigirwsa (Mart. ex DC) Standley (pau d'arco), Foeniculum vulgare Miller (fennel), Rosa canina L. (rose hips) and Matricaria recutita L. (chamomile) gave only slight effects. In general, the most pronounced bioactivities were observed in the plant preparations (infusion>decoction>hydromethanolic extract) with higher levels of phenolic compounds (both flavonoids and phenolic acids). The observed synergisms between the phenolic compounds present in the extracts highlight the use of phytochemicals as future health promoters. However, further studies are necessary to understand the effective mode of action of individual phenolic constituents as also the existence of polyvalence relationships between them.

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The human immune system has numerous properties that make it ripe for exploitation in the computational domain, such as robustness and fault tolerance, and many different algorithms, collectively termed Artificial Immune Systems (AIS), have been inspired by it. Two generations of AIS are currently in use, with the first generation relying on simplified immune models and the second generation utilising interdisciplinary collaboration to develop a deeper understanding of the immune system and hence produce more complex models. Both generations of algorithms have been successfully applied to a variety of problems, including anomaly detection, pattern recognition, optimisation and robotics. In this chapter an overview of AIS is presented, its evolution is discussed, and it is shown that the diversification of the field is linked to the diversity of the immune system itself, leading to a number of algorithms as opposed to one archetypal system. Two case studies are also presented to help provide insight into the mechanisms of AIS; these are the idiotypic network approach and the Dendritic Cell Algorithm.

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Tese de dout., Faculdade de Ciências do Mar e Ambiente, Univ. do Algarve, 2003

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The main obstacles to HIV-1 eradication are linked to the viral ability to evade immune system and establish a reservoir where virus is transcriptionally latent but able to replicate. IFN action and Restriction Factors (RFs) expression, dominant proteins that target multiple steps of the HIV-1 lifecycle, represent an early line of defence Because of their interplay with viral replication, we would like to study the relationship between RFs and the viral amount in latently infected cells.The first part of this project investigates the expression levels variations of a selected group of RFs (APOBEC3G, BST2, TRIM5α, MX2, SAMHD1, SERINC3/5, IFI16 and STING) in HIV-1 patients during the course of infection before and after ART administration by using Real Time qPCR. The second part of this study deals with the role of IFNα and IFNγ, and their role in the immune system disfunction that has been described during chronic inflammation associated to cancer, viral infection such as HIV-1, and autoimmune-disease. Immune Check Point proteins (ICPs) are a group of inhibitory receptors expressed on the cellular surface of immune cells and trigger immunosuppressive signaling pathways leading to T-cell exhaustion and the expression of immune checkpoint molecules (PD-1, PD-L1, TIGIT, LILRB2). The major aim of this project is to assess the clinical meaning of ICPs expression in HIV-1 chronically infected patients to better characterized their involvement in immune system disfunction.

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The catechol (1,2-dihydroxybenzene) is a privileged structural motif among natural antioxidants like flavonoids, owing to its reactivity with alkylperoxyl radicals due to the stability of the semiquinone radical. The exploration of the relevance and mechanism of this non-conventional antioxidant chemistry in heterogenous biomimetic systems (aqueous micelles and unilamellar liposomes) is explored for the first time in Chapter 1. Results show antioxidant behaviour that surpasses that of nature’s premiere antioxidant α-tocopherol and relies on the cross-dismutation of alkylperoxyl and hydroperoxyl radicals at the water-lipid interface with regeneration of the catechol function from the oxidized quinone. The design and synthesis of new biomimetic catechol-type antioxidants by conjugation of thiols (e.g. cysteine) with quinones highlighted an unusual 1,6-type regioselectivity, which had been previously reported but never fully rationalized. Owing to its importance both in nature and in the development of new antioxidants, we investigated it in detail in Chapter 2. We could prove the onsetting of a radical-chain mechanism intermediated by thiyl and thiosemiquinone radicals at the basis of the “anomalous nucleophilic addition” of thiols to ortho-quinones, which paves the way to better understanding of the chemistry of such systems. The oxidation of catechols to the corresponding quinones is also a key reaction in the biosynthesis of melanins, mediated by enzyme Tyrosinase.