298 resultados para Goldman


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Em meio a toda a turbulência que configura um cenário desastroso para as políticas sociais, a população idosa aumenta; com ela, aumenta a demanda por estudos que avaliem os avanços e os impactos derivados desse processo. Mas como o Serviço Social vem se posicionando perante a esta demanda? O que temos produzido sobre a temática? Poderíamos dizer que, em termo de produções, verificamos mais avanços ou retrocessos? Para analisar a produção acadêmica do Serviço Social, utilizei como referenciais as produções Dissertações e Teses sobre o idoso _ dos programas de pós-graduação em Serviço Social de três das principais Universidades públicas do estado do Rio de Janeiro UFF, UFRJ e UERJ_ devido ao fato de elas possuírem programas consolidados desde 2001, motivo pelo qual analisei as obras no período compreendido entre 2001 e 2009 . Busco evidenciar a importância da categoria neste debate, que pressupõe a capacidade teórico-metodológica para analisar seus determinantes, compreendendo o envelhecimento como um processo que possui um grande potencial a ser explorado em estudos e pesquisas, além de constituir-se num instigante desafio intelectual, social e político.

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Aspergillus fumigatus é o principal agente etiológico da aspergilose invasiva, infecção fúngica oportunista com altas taxas de mortalidade afetando, principalmente, pacientes com neutropenia profunda e prolongada. Durante o processo de invasão e disseminação características desta infecção sistêmica, os conídios do fungo inalados e não eliminados pelas células do sistema imune inato diferenciam-se em hifas que, por sua vez, são angioinvasivas. Pouco se conhece sobre as moléculas da parede celular envolvidas na patogênese do A. fumigatus e/ou secretadas por este patógeno. Neste contexto, este trabalho procura ampliar o entendimento desta doença através do estudo de proteínas diferencialmente expressas na superfície de A. fumigatus durante a morfogênese. Foi utilizada uma abordagem proteômica e foram estudados extratos de superfície de células de A. fumigatus em diferentes estágios durante o processo de filamentação. Estas células foram denominadas, de acordo com o tempo de cultivo e a morfologia, como: TG6h (tubo germinativo), H12h ou H72h (hifas). As proteínas de superfície celular foram extraídas, a partir de células intactas, por tratamento brando com o agente redutor DTT (ditiotreitol). Observou-se que o perfil funcional das proteínas expressas por H12h e H72h foi similar, com exceção de proteínas relacionadas à resposta ao estresse, enquanto o perfil para TG6h apresentou diferenças significativas para vários grupos funcionais de proteínas quando comparado às hifas. Desta forma, foram realizados experimentos de proteômica diferencial entre tubo germinativo (TG6h) e a hifa madura (H72h), pela técnica de DIGE (differential gel electrophoresis). Os resultados revelaram que entre as proteínas diferencialmente expressas, aquelas relacionadas às vias de biossíntese e outras denominadas multifuncionais encontraram-se superexpressas em TG6h. Em relação às proteínas de resposta a estresse, observou-se que algumas HSPs eram mais expressas neste morfotipo, enquanto a MnSOD, relativa à resposta ao estresse oxidativo, era mais abundante na hifa. Com exceção da PhiA, integrante da parede celular, as proteínas identificadas como diferencialmente expressas na superfície do A. fumigatus não possuem sinal para secreção identificável, enquadrando-se nas proteínas atípicas de superfície. Foi verificada a integridade da membrana celular após tratamento com DTT, bem como a marcação por biotina das proteínas extraídas, o que comprovou sua localização superficial na célula fúngica. Hipóteses de que estas proteínas sejam endereçadas à parede celular por via secretória alternativa sustentam estes dados. Estas evidências foram confirmadas pelo fato de não terem sido encontradas as mesmas proteínas da superfície na análise do secretoma do A. fumigatus. Além disso, todas as proteínas caracterizadas no secretoma apresentavam sinal de secreção determinado pelo FunSecKB (www.proteomics.ysu.edu/secretomes/fungi.php). A análise do secretoma foi realizada utilizando-se a cepa selvagem AF293 e a mutante ∆prtT, mutante para um fator de transcrição que atua na regulação da secreção de proteases. Os resultados revelam a ALP1 como expressa na cepa selvagem, assim como outras proteases importantes para virulência e desenvolvimento da célula fúngica, estando suprimidas quando o gene prtT foi deletado.

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Age and growth estimates for salmon sharks (Lamna ditropis) in the eastern North Pacific were derived from 182 vertebral centra collected from sharks ranging in length from 62.2 to 213.4 cm pre-caudal length (PCL) and compared to previously published age and growth data for salmon sharks in the western North Pacific. Eastern North Pacific female and male salmon sharks were aged up to 20 and 17 years, respectively. Relative marginal increment (RMI) analysis showed that postnatal rings form annually between January and March. Von Bertalanffy growth parameters derived from vertebral length-at-age data are L∞ =207.4 cm PCL, k=0.17/yr, and t0=−2.3 years for females (n=166), and L∞ =182.8 cm PCL, k=0.23/yr , and t0=−1.9 years for males (n=16). Age at maturity was estimated to range from six to nine years for females (median pre-caudal length of 164.7 cm PCL) and from three to five years old for males (median precaudal length of 124.0 cm PCL). Weight-length relationships for females and males in the eastern North Pacific are W=8.2 × 10_05 × L2.759 –06 × L3.383 (r2 =0.99) and W=3.2 × 10 (r2 =0.99), respectively. Our results show that female and male salmon sharks in the eastern North Pacific possess a faster growth rate, reach sexual maturity earlier, and attain greater weight-at-length than their same-sex counterparts living in the western North Pacific.

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O objetivo desse trabalho é compreender a produção intelectual do autor palestino, Edward W. Said, cuja trajetória heterogênea representou em larga medida uma metáfora teórica dos seus maiores dilemas políticos e conceituais, alguns deles constitutivos do objeto dessa tese. Entendemos que Said define a Cultura como lócus privilegiado para compreender a dominação colonial e, posteriormente, incorpora um discurso político para a formação da chamada identidade nacional Palestina. Procuramos demarcar o paradoxo central da sua obra que diz respeito ao convívio teórico da abordagem pós-colonial com a busca da historicidade do ethos nacional palestino. Entendemos que o paradoxo do Nacionalismo, sua estreita vinculação com o debate pós-colonial e os percursos teóricos decorrentes do engajamento progressivo com a causa nacional Palestina subsidiam outras reflexões que possuem interrelação. São essas; a representação do intelectual na sociedade contemporânea, a relação entre texto e realidade histórica, entendida por meio do conceito de mundanidade, a categoria de exílio como condição ontológica e metáfora epistemológica e o problema da relação entre cultura e imperialismo. Esses percursos de análise orientam-se por um objetivo mais geral que é a análise da centralidade e respectiva atualidade da obra de Edward W. Said na Historiografia Pós-Colonial.

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Fluctuations in primary productivity at two subalpine lakes reveal both meteorological and biological influences. At Castle Lake, California, large-scale climate events such as the El Niño/Southern Oscillation affect total annual production and, combined with human fishing activity, modify the seasonal pattern of productivity. At Lake Tahoe, California-Nevada, local spring weather conditions modulate annual production and its seasonality by determining the depth of mixing and resulting internal nutrient load. Climatic conditions also contribute to deviations from the long-term trend in productivity by increasing the incidence of forest fires and through anomalous external nutrient loads during precipitation extremes. A 3-year cycle in productivity of as yet unknown origin has also been detected at Lake Tahoe.

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The D2 dopamine (DA) receptor agonist, quinpirole, was characterized in young adult monkeys, young reserpine-treated monkeys and aged monkeys to assess the contribution of DA to age-related loss of prefrontal cortical (PFC) cognitive function, Monkeys were tested on a delayed response memory task that depends on the PFC, and a fine motor task that taps the functions of the motor cortex, In young adult monkeys, low quinpirole doses impaired performance of the PFC and fine motor tasks, while higher doses improved memory performance and induced dyskinesias and ''hallucinatory-like'' behaviors. The pattern of the quinpirole response in reserpine-treated monkeys suggested that the impairments in delayed response and fine motor performance resulted from drug actions at D2 autoreceptors, while the improvement in delayed response performance, dyskinesias and ''hallucinatory-like'' behaviors resulted from actions at postsynaptic receptors. In aged monkeys, low doses of quinpirole continued to impair fine motor performance, but lost their ability to impair delayed response performance. The magnitude of cognitive improvement and the incidence of ''hallucinatory-like'' behaviors were also reduced in the aged animals, suggesting some loss of postsynaptic D2 receptor function, The pattern of results is consistent with the greater loss of DA from the PFC than from motor areas in aged monkey brain (Goldman-Rakic and Brown, 1981; Wenk et al., 1989), and indicates that DA depletion contributes significantly to age-related cognitive decline.

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<正> 聚乙烯醇(Polyvinyl alcohol)简称PVA,最早是唐斯(Downs,1943)应用于小型昆虫,小型节肢动物的封固剂,以后布鲁克和戈德曼(Brooke and Goldman,1949)将此剂配方作了改进。 在国内,最早是蒲蛰龙和利翠英(1951)介绍了用聚乙烯醇封存小昆虫整体和部分器官构造。尹文英(1954)用它封固鱼类寄生虫单殖吸虫和甲壳动物。我于1956年用它处理寄生线虫的口囊、交合刺等坚硬的结构都取得很好的效果。现将其配方和使用的体会介绍如下:

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The microstructure of two bicomponent and one tricomponent segmented copolymers, based on polydimethylsiloxane, poly(p-hydroxystyrene) or/and polysulfone, were investigated using an extended Goldman-Shen pulse sequence, proton spin-spin relaxation measurements, and C-13 and Si-29 NMR spectra. The results indicate that there exist four phases with different sizes, components and morphological structure in the segmented copolymers studied in this work, i. e., a rigid-chain phase of very slow motion, a rigid-chain-rich phase of slow motion, a flexible-chain-rich phase of fast motion and a flexible-chain phase of faster motion. The sizes of different domains, calculated from the spin diffusion rates, are about 50-100 angstrom for the flexible-chain-rich phase of fast motion and 200-300 angstrom for the flexible-chain phase of faster motion. The relative quantities of polydimethylsiloxane in the flexible-chain phase of fast motion are slightly different in different kinds of segmented copolymers.

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An extended Goldman-Shen pulse sequence was used to observe indirectly the proton spin diffusion in the blends of polystyrene (PS) with poly(2,6-dimethyl-1,4-phenylene oxides) (PPO). The results indicate that the average distance between PS and PPO is less than 5 angstrom in the intimately mixed phase, but there are heterogeneous domains on a 100-angstrom scale. The data of spin relaxation of carbons, T1(C), for homopolymers and their blends suggest that there is a strong pi-pi electron conjugation interaction between the aromatic rings of PS and those of PPO, while the aromatic rings of PPO drive the aromatic rings of PS to move cooperatively. It is the cooperative motion that markedly improves the impact strength of PS.

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Weekly injections of Concanavalin A (Con A) were performed in BALB/c mice to evaluate the pattern of cytokine production and liver injury. High serum levels of tumor necrosis factor alpha (TNF-alpha), interleukin 2 (IL-2), IL-4, and interferon gamma (IFN-gamma) were found in the serum after the first 2 injections of Con A but rapidly decreased from the third injection. Conversely, IL-10 serum levels after repeated Con A challenge increased by 7 times from week 1 to 20. In vivo depletion studies indicated that CD4(+) T cells are essential in IL-10 production. Hepatocyte necrosis was only observed after the first injections of Con A whereas centrilobular inflammatory infiltrates persisted up to 20 weeks. Perisinusoidal liver fibrosis was also increasingly detected in BALB/c mice, whereas no fibrous change was observed in nude mice after 6 weeks of Con A challenge. The number of stellate cells, detected by immunostaining, increased after 20 weeks of Con A injections. Liver cytokine messenger RNA (mRNA) expression after 20 weeks showed expression of transforming growth factor beta1 (TGF-beta1), IL-10, and IL-4 whereas IL-2 was no more expressed. The present study shows that mice repeatedly injected with Con A develop liver fibrosis. The cytokine-release pattern observed after 1 injection of Con A is rapidly shifted towards an immunomodulatory phenotype characterized by the systemic production of large amounts of IL-10.

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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: Interleukin-10 (IL-10) is currently being extensively studied in clinical trials for the treatment of Crohn's disease (CD). Only marginal effects have, however, been reported, and the dose-response curve was bell-shaped contrasting with the reported data from in vitro experiments. AIM: To use another in vitro model to analyze the effect of rhIL-10 and rhIL-4 on the spontaneous mucosal TNF-alpha secretion in patients with CD, and to characterize the phenotype of the cells targeted by rhIL-10. METHODS: Non-inflamed colon biopsies from CD patients were cultured for 16 hours in presence of different concentrations of rhIL-10 or rhIL-4. The numbers of TNF-alpha-secreting cells among isolated lamina propria mononuclear cells (LPMNC) were estimated by Elispot. RESULTS: Both rhIL-10 and rhIL-4 down-regulate TNF-alpha secretion by LPMNC from CD patients, with a more pronounced effect with rhIL-10. These effects were closely linked to the cytokine concentrations used, with a bell-shaped dose-response curve. Residual TNF-alpha secretion, in the presence of optimal rhIL-10 concentration was mainly attributable to CD3+ T cells. In contrast, at higher rhIL-10 concentrations, CD3- cells contributed significantly to the TNF-alpha secretion. CONCLUSIONS: The in vitro model we used, demonstrates that IL-4, but mostly IL-10, efficiently suppresses TNF-alpha secretion in LPMNC from CD patients, with a dose-response curve similar to results obtained in vivo. Resistance at high rhIL-10 concentrations was associated with a change in the phenotype of TNF-alpha-secreting cells.

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Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by polyclonal B cell activation and by the production of anti-double-stranded (ds) DNA antibodies. Given the inhibitory effects of IL-12 on humoral immune responses, we investigated whether IL-12 displayed such an activity on in vitro immunoglobulin production by SLE PBMC. Spontaneous IgG, IgG1, IgG2, IgG3 and IgM antibody production was dramatically reduced by addition of IL-12. These results were confirmed by Elispot assays detecting IgG- and anti-dsDNA-secreting cells. While IL-6 and TNF titres measured in PBMC supernatants were not modified by addition of IL-12, interferon-gamma (IFN-gamma) titres were up-regulated and IL-10 production down-regulated. Since addition of IFN-gamma did not down-regulate immunoglobulin production and since the inhibitory activity of IL-12 on immunoglobulin synthesis was not suppressed by anti-IFN-gamma antibody, we concluded that the effect of IL-12 on immunoglobulin production was not mediated through IFN-gamma. Our data also argue against the possibility that down-regulation of endogenous IL-10 production was responsible for the effect of IL-12. Thus, inhibition of IL-10 production by IFN-gamma was not accompanied by inhibition of immunoglobulin production, and conversely, restoration of IL-10 production by anti-IFN-gamma antibody did not suppress the inhibitory activity exerted by IL-12 on immunoglobulin production. Taken together, our data indicate that reduction of excessive immunoglobulin and anti-dsDNA antibody production by lupus PBMC can be achieved in vitro by IL-12, independently of IFN-gamma and IL-10 modulation.

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BACKGROUND: Cytokines secreted by intestinal T lymphocytes probably play a critical role in regulation of the gut associated immune responses. AIMS: To quantify interferon gamma (IFN-gamma) and interleukin 4 (IL-4) secreting cells (SC) among human intraepithelial (IEL) and lamina propria (LPL) lymphocytes from the duodenum and right colon in non-pathological situations and in the absence of in vitro stimulation. PATIENTS: Duodenal and right colonic biopsy specimens were obtained from patients with no inflammation of the intestinal mucosa. METHODS: Intraepithelial and lamina propria cell suspensions were assayed for numbers of cells spontaneously secreting IFN-gamma and IL-4 by a two site reverse enzyme linked immunospot technique (ELISPOT). RESULTS: The relatively high proportion of duodenal lymphocytes spontaneously secreting IFN-gamma (IEL 3.6%; LPL 1.9%) and IL-4 (IEL 1.3%; LPL 0.7%) contrasted with the very low numbers of spontaneously IFN-gamma SC and the absence of spontaneously IL-4 SC among peripheral blood mononuclear cells. In the basal state, both IFN-gamma and IL-4 were mainly produced by CD4+ cells. Within the colon, only 0.2% of IEL and LPL secreted IFN-gamma in the basal state, and 0.1% secreted IL-4. CONCLUSIONS: Compared with peripheral lymphocytes substantial proportions of intestinal epithelial and lamina propria lymphocytes spontaneously secrete IFN-gamma and/or IL-4. These cytokines are probably involved in the normal homoeostasis of the human intestinal mucosa. Disturbances in their secretion could play a role in the pathogenesis of gastrointestinal diseases.