935 resultados para HLA Antigens


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随着现代武器装备的不断更新,武器系统的可测试性成为保证系统实际性能指标的重要手段。本文简述了新一代某精确制导导弹测试系统的视景仿真的设计与实现。在测试系统中,引入了新一代的分布式交互仿真技术-高级体系结构(HLA)、虚拟现实技术和视景生成技术,逼真的显示虚拟战场、作战过程。视景模拟可分为视景建模、视景渲染和视景生成三部分,借助于专门的图形处理技术和灵活有效的视景驱动,既增加了视景的逼真度,又确保了系统运行的实时性;共享的虚拟试验场包括山地、沙漠、大海等多个背景及坦克、飞机、军舰等多种动、静态武器装备模型;光照、雾、火光、碎片等各种特殊效果的实现,丰富了试验场的连续性和真实感;为测试系统作了部分的技术方法研究,包括海浪建模、特殊效果模型、地形匹配、碰撞检测;提供多个目标运动模型,可为任意或预定运动;根据导弹飞行姿态及速度来模拟环境场景及目标物,并根据控制操作的要求对场景和目标物进行缩放、漫游、旋转和三维形态变换;为进一步的数据采集和分析,能够记录并回放多个历史记录;制定了数据调度策略,在不牺牲真实性的情况下,保证了系统运行的实时性,解决了系统的一大难点。基于分布式虚拟现实技术的视景仿真能够为导弹系统的可测试性提供了更高的可信度,必将使导弹性能迈上一个新台阶,同时能为多种武器提供测试和训练。

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RESUMO: Com o objetivo de avaliar o desempenho agronômico de genótipos de girassol nas condições edafoclimáticas do primeiro semestre de 2015 na Chapada do Araripe, instalou-se um experimento na Estação Experimental do Instituto Agronômico de Pernambuco (IPA), no município de Araripina, Estado de Pernambuco. O delineamento foi o de blocos ao acaso, com quatro repetições e 13 tratamentos, correspondendo aos genótipos de girassol: M734, NTC 90, BRS G43, BRS G44, BRS G45, BRS G46, SYN 065, HLA 2013, HLA 2014, HLA 2015, HLA 2016, HLA 2017 e SYN 045. Avaliaram-se as seguintes características: sobrevivência final, floração inicial, maturação fisiológica, altura média do capítulo, peso de 1000 aquênios, diâmetro médio dos capítulos, produção final de aquênios, curvatura do capítulo e plantas acamadas, quebradas e atacadas por pássaros. Os genótipos apresentaram diferenças morfoagronômicas quando cultivados no primeiro semestre em condições edafoclimáticas da região do Araripe, com exceção da variável sobrevivência. O genótipo NTC 90 alcançou o maior peso de aquênios. Todos os genótipos, exceto HLA 2015, apresentaram elevado rendimento de grãos. Os caracteres plantas acamadas, quebradas, atacadas por pássaros ou a curvatura do capítulo não foram relacionadas às diferentes cultivares. ABSTRACT: The study aimed to evaluate the agronomic performance of different sunflower genotypes in edaphoclimatic conditions of Araripe region in the first semester of 2015. The experiment was established at the Experimental Station of Instituto Agronômico de Pernambuco (IPA), Araripina, Pernambuco, Brazil. Experimental design was a randomized blocks with thirteen treatments, corresponding to the sunflower genotypes: M734, NTC 90, BRS G43, BRS G44, BRS G45, BRS G46, SYN 065, HLA 2013, HLA 2014, HLA 2015, HLA 2016, HLA 2017 e SYN 045, with four replicates. The following characteristics were evaluated: final survival, early flowering, physiological maturity, average plant height, weight of 1,000 seeds, average flower diameter, final seed production, flower head curvature, lodged, broken and damaged by birds plants. The genotypes showed morphoagronomic differences when grown in the first semester of 2015 on edaphoclimatic conditions of the Araripe region, except for the variable survival. The NTC 90 genotype achieved the highest weight of head flower. All genotypes, except HLA 2015 showed high grain yield. The characters lodged, broken and damaged plants by birds or curvature of the head flower were not related to the different cultivars.

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RESUMO: O presente trabalho tem por objetivo caracterizar o comportamento de 16 genótipos de girassol em ambiente de sequeiro e ambiente irrigado do Cerrado do Distrito Federal visando aumentar disponibilidade de cultivares mais produtivas e adaptadas. Os ensaios foram conduzidos na área experimental da Embrapa Cerrados, Planaltina, DF. Os ensaios foram arranjados experimentalmente em blocos ao acaso, com quatro repetições. Os genótipos avaliados foram: CF 101, ADV 5504, BRS G42, BRS 323, HELIO 250, HELIO 251, SYN 045, SYN 3950HO, MG 305, MG 360, AGUARÁ 04, AGUARÁ 06, PARAÍSO 20, GNZ NEON, HLA 2012 e M734. Os caracteres avaliados foram rendimento estimado de grãos, tamanho do capítulo, peso de mil aquênios, altura de plantas, teor de óleo e dias para floração inicial. Houve diferenças significativas entre os genótipos para todas as características avaliadas. Dos 16 genótipos avaliados, os híbridos SYN 045 (3.786,2 kg ha-1) e MG 305 (4.987,2 kg ha-1) se sobressaíram quanto ao rendimento estimado de grãos. Quanto ao teor de óleo, os híbridos MG 306 (53,95%) e SYN 3950HO (49,49%) se destacaram. Foram identificados os genótipos mais promissores dentre os avaliados, podendo ser explorados em programas de melhoramento que visam o desenvolvimento de cultivares mais adaptadas.

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RESUMO:Com o objetivo de avaliar o comportamento agronômico de genótipos de girassol no Cerrado do Distrito Federal, foram conduzidos ensaios na safrinha dos anos de 2014 e 2015, na estação experimental da Embrapa Cerrados, Planaltina, DF. O delineamento experimental foi de blocos ao acaso com quatro repetições, e foram avaliados 12 genótipos de girassol: HLA 2015, NTC 90, SYN 065, M734, BRS G44, HLA 2014, BRS G45, BRS G43, HLA 2013, HLA 2017, BRS G46, HLA 2016. As características avaliadas foram rendimento de grãos, tamanho do capitulo, peso de mil aquênios, altura de plantas e dias de floração inicial. Diferenças significativas foram encontradas para as características avaliadas. Os genótipos que se destacaram em relação ao rendimento de grãos foram HLA 2014 (3.161 kg ha-1) e a testemunha M743 (3.212 kg ha-1). Além disso, o ensaio do ano 2014 apresentou uma média de rendimento maior (2.829 kg ha-1) e mais precoces (63,10 dias) em relação a 2015. O trabalho permitiu a identificação de materiais promissores para exploração em programas de melhoramento genético. ABSTRACT: Aiming the evaluation on agronomic behavior of sunflower genotypes in the Brazilian savannah, experiments were carried on in the second crop of 2014 and 2015 at Centro de Pesquisa Agropecuária dos Cerrados (Embrapa), Planaltina, DF. A complete randomized block design was used with four replications and 12 genotypes of sunflower were analyzed: HLA 2015, NTC 90, SYN 065, M734, BRS G44, HLA 2014, BRS G45, BRS G43, HLA 2013, HLA 2017, BRS G46, HLA 2016.The evaluated characteristics were grain yield, head, weight thousand achenes, plant height, and flowering time. Significant differences were found in all evaluated characteristics. The genotypes that stood out in seed yield were HLA 2014 (3161 kg ha-1) and M743 (3212 kg ha-1). Besides, the 2014 experiment presented a seed yield average higher (2829 kg ha-1), and earlier flowering (63,10 days) when compared to 2015 experiment. This study allowed the identification of promising materials to explore in breeding programs.

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Neal, M., Meta-stable memory in an artificial immune network, Proceedings of the 2nd International Conference on Artificial Immune Systems {ICARIS}, Springer, 168-180, 2003,LNCS 2787/2003

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The Extradomain A from fibronectin (EDA) has an immunomodulatory role as fusion protein with viral and tumor antigens, but its effect when administered with bacteria has not been assessed. Here, we investigated the adjuvant effect of EDA in mice immunizations against Salmonella enterica subspecies enterica serovar Enteritidis (Salmonella Enteritidis). Since lipopolysaccharide (LPS) is a major virulence factor and the LPS O-polysaccharide (O-PS) is the immunodominant antigen in serological diagnostic tests, Salmonella mutants lacking O-PS (rough mutants) represent an interesting approach for developing new vaccines and diagnostic tests to differentiate infected and vaccinated animals (DIVA tests). Here, antigenic preparations (hot-saline extracts and formalin-inactivated bacterins) from two Salmonella Enteritidis rough mutants, carrying either intact (SE Delta waaL) or deep-defective (SE Delta gal) LPS-Core, were used in combination with EDA. Biotinylated bacterins, in particular SE Delta waaL bacterin, decorated with EDAvidin (EDA and streptavidin fusion protein) improved the protection conferred by hot-saline or bacterins alone and prevented significantly the virulent infection at least to the levels of live attenuated rough mutants. These findings demonstrate the adjuvant effect of EDAvidin when administered with biotinylated bacterins from Salmonella Enteritidis lacking O-PS and the usefulness of BEDA-SE Delta waaL as non-live vaccine in the mouse model.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

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The Gastro-Intestinal (GI) tract is a unique region in the body. Our innate immune system retains a fine homeostatic balance between avoiding inappropriate inflammatory responses against the myriad commensal microbes residing in the gut while also remaining active enough to prevent invasive pathogenic attack. The intestinal epithelium represents the frontline of this interface. It has long been known to act as a physical barrier preventing the lumenal bacteria of the gastro-intestinal tract from activating an inflammatory immune response in the immune cells of the underlying mucosa. However, in recent years, an appreciation has grown surrounding the role played by the intestinal epithelium in regulating innate immune responses, both in the prevention of infection and in maintaining a homeostatic environment through modulation of innate immune signalling systems. The aim of this thesis was to identify novel innate immune mechanisms regulating inflammation in the GI tract. To achieve this aim, we chose several aspects of regulatory mechanisms utilised in this region by the innate immune system. We identified several commensal strains of bacteria expressing proteins containing signalling domains used by Pattern Recognition Receptors (PRRs) of the innate immune system. Three such bacterial proteins were studied for their potentially subversive roles in host innate immune signalling as a means of regulating homeostasis in the GI tract. We also examined differential responses to PRR activation depending on their sub-cellular localisation. This was investigated based on reports that apical Toll-Like Receptor (TLR) 9 activation resulted in abrogation of inflammatory responses mediated by other TLRs in Intestinal Epithelial Cells (IECs) such as basolateral TLR4 activation. Using the well-studied invasive intra-cellular pathogen Listeria monocytogenes as a model for infection, we also used a PRR siRNA library screening technique to identify novel PRRs used by IECs in both inhibition and activation of inflammatory responses. Many of the PRRs identified in this screen were previously believed not to be expressed in IECs. Furthermore, the same study has led to the identification of the previously uncharacterised TLR10 as a functional inflammatory receptor of IECs. Further analysis revealed a similar role in macrophages where it was shown to respond to intracellular and motile pathogens such as Gram-positive L.monocytogenes and Gram negative Salmonella typhimurium. TLR10 expression in IECs was predominantly intracellular. This is likely in order to avoid inappropriate inflammatory activation through the recognition of commensal microbial antigens on the apical cell surface of IECs. Moreover, these results have revealed a more complex network of innate immune signalling mechanisms involved in both activating and inhibiting inflammatory responses in IECs than was previously believed. This contribution to our understanding of innate immune regulation in this region has several direct and indirect benefits. The identification of several novel PRRs involved in activating and inhibiting inflammation in the GI tract may be used as novel therapeutic targets in the treatment of disease; both for inducing tolerance and reducing inflammation, or indeed, as targets for adjuvant activation in the development of oral vaccines against pathogenic attack.

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Inflammatory bowel diseases (IBD), encompasses a range of chronic, immune-mediated inflammatory disorders that are usually classified under two major relapsing conditions, Crohn’s Disease (CD) and ulcerative colitis (UC). Extensive studies in the last decades have suggested that the etiology of IBD involves environmental and genetic factors that lead to dysfunction of epithelial barrier with consequent deregulation of the mucosal immune system and inadequate responses to gut microbiota.Over the last decade, the microbial species that has attracted the most attention, with respect to CD etiology, is Eschericia coli. In CD tissue, E. coli antigens have also been identified in macrophages within the lamina propria, granulomas, and in the germinal centres of mesenteric lymph nodes of patients. They have been shown to adhere to and invade intestinal epithelial cells whilst also being able to extensively replicate within macrophages. Through the work of genome-wide association studies (GWAS), there is growing evidence to suggest that the microbial imbalance between commensal and pathogenic bacteria in the gut is aided by a defect in the innate immune system. Autophagy represents a recently investigated pathway that is believed to contribute to the pathogenesis of CD, with studies identified a variant of the autophagy gene, ATG16L1, as a susceptibility gene. The aim of my thesis was to study the cellular and molecular mechanism promoted by E.coli strains in epithelial cells and to assess their contribution to IBD pathology. To achieve this we focused on developing both an in vitro and in vivo model of AIEC infection. This allowed us to further our knowledge on possible mechanisms utilised by AIEC that promoted their survival, as well as developing a better understanding of host reactions. We demonstrate a new survival mechanism promoted by E.coli HM605, whereby it induces the expression of the anti-apoptotic proteins Bcl-XL and BCL2, all of which is exacerbated in an autophagy deficient system. We have also demonstrated the presence of AIEC-induced inflammasome responses in epithelial cells which are exacerbated in an autophagy deficient system and expression of NOD-like receptors (NLRs) which might mediate inflammasome responses in vivo. Finally, we used the Citrobacter rodentium model of infectious colitis to identify Pellino3 as an important mediator in the NOD2 pathway and regulator of intestinal inflammation. In summary, we have developed robust and versatile models of AIEC infection as well as provide new insights into AIEC mediated survival pathways. The collected data provides a new perception into why AIEC bacteria are able to prosper in conditions associated with Crohn’s disease patients with a defect in autophagy.

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BACKGROUND & AIMS: Eosinophils are observed in several liver diseases, but their contribution in the pathogenesis of these disorders remains poorly investigated. Concanavalin A (Con A)-induced hepatitis is an experimental model of immune-mediated liver injury in which natural killer T (NKT) cells play a critical role through the production of interleukin (IL)-4 and the expression of Fas ligand (FasL). Because activated NKT cells also produce IL-5, a critical cytokine for eosinophil maturation and function, the role of IL-5 was investigated in this model. METHODS: IL-5-deficient mice, eosinophil depletion in wild-type (WT) mice, and NKT cell transfer from WT- or IL-5-deficient mice into NKT cell-deficient mice were used to assess the role of IL-5 and eosinophils. RESULTS: Liver eosinophil infiltrate and IL-5 production were observed after Con A challenge. Liver injury was dramatically reduced in IL-5-deficient or eosinophil-depleted mice. In addition, residual hepatitis observed in Fas-deficient mice was abolished after IL-5 neutralization. Finally, we showed that NKT cells constituted a critical source of IL-5. Indeed, transfer of WT NKT cells to mice lacking NKT cells restored liver injury, whereas transfer of IL-5-deficient NKT cells did not. CONCLUSIONS: These observations highlight the pathologic role of IL-5 and eosinophils in experimental immune-mediated hepatitis.

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BACKGROUND/AIMS: The intestinal immune system faces large amounts of antigens, and its regulation is tightly balanced by cytokines. In this study, the effect of intestinal flow diversion on spontaneous secretion of interleukin (IL)-4 and interferon (IFN)- gamma was analysed. METHODS: Eight patients (two with Crohn's disease, four with ulcerative colitis, and two with previous colon cancer) carrying a double lumen small bowel stoma after a total colectomy procedure were included in the study. For each patient, eight biopsy samples were taken endoscopically from both the diverted and non-diverted part of the small bowel. Intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) were isolated separately and assayed for numbers of cells spontaneously secreting IL-4 and/or IFN-gamma by an ELISPOT technique. RESULTS: Compared with the non-diverted mucosa, a significant decrease in the number of spontaneously IFN-gamma secreting CD3 lymphocytes was observed in the diverted small bowel mucosa among both IELs (p = 0.008) and LPLs (p = 0.007). The same results, although less significant, were obtained for IL-4, especially in LPLs (p = 0.01). CONCLUSION: The intestinal content influences the spontaneous secretion of IFN-gamma and IL-4 by intestinal lymphocytes. These results could help to elucidate the anti-inflammatory role of split ileostomy in patients suffering from inflammatory bowel diseases.

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BACKGROUND: Persistent polyclonal B cell lymphocytosis (PPBL) is a rare condition characterized by increased IgM and large excess of B cells with an IgD(+) CD27(+) phenotype. In normal individuals, these cells play a central role in the defense against pneumococcal infection. So far, few studies have characterized humoral immune responses in PPBL patients. We therefore measured IgG directed against S. pneumoniae antigens in a 51 yr-old woman with PPBL before and after vaccination with a pneumococcal 23-valent polysaccharide vaccine. METHODS: Antibodies against pneumococcal antigens were measured first with an overall immunoassay using microplates coated with the 23-valent pneumococcal vaccine. A serotype-specific test was also performed according to the WHO consensus protocol. RESULTS: Despite a large number of IgD(+) CD27(+) cells, our patient had low baseline titers of IgG directed against pneumococcal antigens and did not significantly respond to a 23-valent polysaccharide vaccine against S. pneumoniae. On the contrary, she had good titers of IgG directed against tetanus toxoid. CONCLUSION: IgM(+) IgD(+) CD27(+) cells which accumulate in this patient with typical PPBL patient failed to perform IgG isotype switch after a polysaccharide vaccine. The potential mechanisms and relationships with the main features of PPBL are discussed. Further studies on a larger number of similar patients are needed.

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Transactivation is a process whereby stimulation of G-protein-coupled receptors (GPCR) activates signaling from receptors tyrosine kinase (RTK). In neuronal cells, the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) acting through the GPCR VPAC-1 exerts trophic effects by transactivating the RTK TrkA receptor for the nerve growth factor (NGF). Both PACAP and NGF have pro-inflammatory activities on monocytes. We have tested the possibility that in monocytes, PACAP, as reported in neuronal cells, uses NGF/TrkA signaling pathway. In these cells, PACAP increases TrkA tyrosine phosphorylations through a PI-3kinase dependent but phospholipase C independent pathway. K252a, an inhibitor of TrkA decreases PACAP-induced Akt and ERK phosphorylation and calcium mobilisation resulting in decreases in intracellular H2O2 production and membrane upregulation of CD11b expression, both functions being inhibited after anti-NGF or anti-TrkA antibody treatment. K252a also inhibits PACAP-associated NF-KB activity. Monocytes increase in NGF production is seen after micromolar PACAP exposure while nanomolar treatment which desensitizes cells to high dose of PACAP prevents PACAP-induced TrkA phosphorylation, H2O2 production and CD11b expression. Finally, NGF-dependent ERK activation and H2O2 production is pertussis toxin sensitive. Altogether these data indicate that in PACAP-activated monocytes some pro-inflammatory activities occur through transactivation mechanisms involving VPAC-1, NGF and TrkA-associated tyrosine kinase activity.

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BACKGROUND AND AIMS: Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) has been shown to act as a negative regulator of T cell function and has been implicated in the regulation of T helper 1 (Th1)/Th2 development and the function of regulatory T cells. Tests were carried out to determine whether anti-CTLA-4 treatment would alter the polarisation of naive T cells in vivo. METHODS: Mice were treated with anti-CTLA-4 monoclonal antibody (mAb) (UC10-4F10) at the time of immunisation or colonic instillation of trinitrobenzene sulfonic acid (TNBS). The cytokines produced by lymph node cells after in vitro antigenic stimulation and the role of indoleamine 2,3 dioxygenase (IDO) and of interleukin-10 (IL-10) were tested, and the survival of mice was monitored. RESULTS: Injection of anti-CTLA-4 mAb in mice during priming induced the development of adaptive CD4(+) regulatory T cells which expressed high levels of ICOS (inducible co-stimulator), secreted IL-4 and IL-10. This treatment inhibited Th1 memory responses in vivo and repressed experimental intestinal inflammation. The anti-CTLA-4-induced amelioration of disease correlated with IDO expression and infiltration of ICOS(high) Foxp3(+) T cells in the intestine, suggesting that anti-CTLA-4 acted indirectly through the development of regulatory T cells producing IL-10 and inducing IDO. CONCLUSIONS: These observations emphasise the synergy between IL-10 and IDO as anti-inflammatory agents and highlight anti-CTLA-4 treatment as a potential novel immunotherapeutic approach for inducing adaptive regulatory T cells.

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BACKGROUND: Breast cancer is a heterogeneous disease. Predictive biological markers (BM) of responsiveness to therapy need to be identified. Evaluation of BM is mainly done at the primary site. However, in the adjuvant therapy of breast cancer, the main goal is control of micrometastases. It is still unknown whether heterogeneity in the expression of BM between the primary site and its micrometastases exists. OBJECTIVE: To evaluate the expression of some BM with potential predictive value from the primary breast cancer site and metastatic ipsilateral axillary lymph nodes. PATIENTS AND METHODS: Focality (percentage of positive cells) and intensity staining scores were evaluated for each marker. Freshly cut sections (4 microm) from embedded blocks of breast cancer fixed in formalin or bouin were put onto superfrost slides (Menzel-Gläser). Protein expression was evaluated immunohistochemically (IHC) using monoclonal antibodies against: topo II-alpha (clone KiS1, 1 microg/ml, Roche) with a trypsine pre-treatment (P); HSP27 (clone G3.1, 1/60, Biogenex), HSP70 (clone BRM.22, 1/80, Biogenex) and HER2 (clone CB11, 1/40, Novocastra; without P); p53 (clone D07, 1/750, Dako) and bcl-2 (clone 124, 1/60, Dako) with citrate buffer as P. RESULTS: Overall, the percentage of discordant marker status in the primary tumour and its metastatic lymph nodes was 2% for HER2, 6% for p53, 15% for bcl-2, 19% for topoisomerase II-alpha, 24% for HSP27 and 30% for HSP70. For the subgroup of patients with positive BM in the primary tumour, the percentage of discordance was 6% for HER2, 7% for p53, 14% for bcl-2, 19% for HSP70, 21% for topoisomerase II-alpha and 36% for HSP27. For the subgroup of patients with positive BM in the lymph nodes, the percentage of discordance was 9% for bcl-2, 15% for HER2 and p53, 21% for topoisomerase II-alpha, 22% for HSP27 and 25% for HSP70. CONCLUSIONS: 1) No biological marker had 100% concordant results. 2) Although some discordant cases might be explained by the limitations of the IHC technique, future studies aiming to evaluate the predictive value of BM in the adjuvant therapy of breast cancer should take into account a possible difference in BM expression between the primary and the metastatic sites.