1000 resultados para 321306 Cirugía experimental
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Lagochilascaris minor is the etiological agent of lagochilascariosis, a disease that affects the neck region and causes exudative abscesses, with eggs, adult parasites and L3/L4 larvae in the purulent exudates. Mice are now considered to be intermediate hosts for the parasite. To determine the pattern of infection in B1 cell-deficient mice, experimental lagochilascariosis was studied in BALB/c and X-chromosome-linked immunodeficient (xid) mice. BALB.xid-infected mice showed lower numbers of larvae. Third-stage larvae, fourth-stage larvae and adult parasites were found in both strains. BALB/c mice produced IgM, IgG, IgA and IgE against the crude extract and secreted/excreted antigens of the parasite. On the other hand, BALB.xid mice did not produce IgM and produced lower levels of IgG and IgA, and similar quantities of IgE.
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O estudo objetivou avaliar a atividade in vivo do itraconazol e terbinafina no tratamento da esporotricose cutânea experimental. Foram utilizados 80 ratos Wistar divididos em quatro grupos (TERB20, TERB30, ITRA e CONT) inoculados no coxim plantar esquerdo com 0,2ml de solução contendo 2x103 células de Sporothrix schenckii/ml e tratados com terbinafina (20 e 30mg/kg), itraconazol (10mg/kg) e placebo durante 13 semanas. As lesões do sítio de inoculação foram avaliadas e mensuradas semanalmente, assim como a disseminação das mesmas. Após foi realizada análise micológica e histopatológica. Os resultados demonstraram que os animais do grupo ITRA diferiram estatisticamente em todos os parâmetros avaliados em relação ao CONT. Em relação à terbinafina, não houve diferenças estatísticas entre os grupos tratados e controle. Pode-se confirmar a boa atividade do itraconazol no tratamento da esporotricose e a pouca eficácia da terbinafina nas doses utilizadas, sendo necessários mais estudos com este antifúngico.
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A técnica de Ensaios Não Destrutivos (END) baseada em células bacterianas (CB) foi proposta recentemente e tem demonstrado viabilidade na identificação de micro defeitos superficiais, com espessuras e profundidades inferiores a 5 μm, em vários materiais de engenharia. O conhecimento processual já é significativo, mas diversos aspectos carecem de desenvolvimentos, nomeadamente, a interacção das bactérias com outros materiais, o limiar de detectabilidade da técnica, a aplicação a defeitos naturais ou o comportamento dinâmico das bactérias sujeitas a campos eléctricos ou magnéticos. Este trabalho pretendeu ser um passo em frente no conhecimento da técnica. Os principais objectivos foram alargar a documentação sobre a interacção bactéria-material, determinar o menor defeito padrão possível de detectar, estabelecer e validar um modelo analítico da dinâmica das bactérias sujeitas a forças exteriores, e comparar o desempenho da técnica com os END por líquidos penetrantes (LP). Foi desenvolvido e testado um protótipo para aplicação de campos magnéticos permanentes triaxiais. A bactéria Rhodococcus erythropolis foi usada na inspecção dos materiais AA1100, AISI 316L, WC, titânio, NiTi, ouro, ABS e lentes oftálmicas, com defeitos padrão por micro e nano indentação e riscagem, assim como os defeitos existentes em soldaduras laser. A técnica foi testada nos padrões de sensibilidade dos LP para efeitos de comparação. Verificou-se que é possível identificar defeitos de nano indentação com largura e profundidades de aproximadamente 5,3 μm e 0,4 μm, respectivamente, e que também são identificados os defeitos dos padrões sensibilidade dos LP, com cerca de 1 μm de espessura.
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INTRODUCTION: The responsibility of Schistosoma mansoni in female infertility is still controversial. This study was conducted to evaluate the effect of acute and chronic schistosomiasis mansoni infection on the endometrium using immunohistochemical analysis of uterine hormone receptor expression. METHODS: Twenty-four nonpregnant swiss albino mice were divided into three groups: control, noninfected; acute; and chronic Schistosoma mansoni infection. Histological sections of uterine specimens were examined by light microscope with an image analyzing system to detect structural histological, estrogen receptor (ER) and progesterone receptor (PR) expression in the endometrium. RESULTS: No secretory phase was detected in the endometrium in acute and chronic Schistosoma infection. Hormone receptor expression (ER and PR) showed statistically significant differences among the groups (p< 0.05), with significant low ER hormone expression in chronic infection, compared to control proliferative, control secretory and acute infection cases, and statistically significant high PR expression in both acute and chronic infection cases compared to the control secretory cases (p< 0.05). CONCLUSIONS: Schistosomiasis mansoni seems to have an important impact on the hormone expression of affected women. Further studies to explore the mechanism of such changes are recommended.
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Este projecto apresenta uma edição crítca do romance Um buraco na boca, de António Aragão, elaborada a partr dos testemunhos disponíveis na tradição impressa. É feita uma súmula do percurso e obra do autor, com destaque para as suas criações no campo da fcção. Associado a esse trabalho, apresenta-se uma proposta de defnição do conceito de romance experimental e respectvo mapeamento das produções que encaixam no modelo proposto. Faz-se ainda um comentário sobre os actuais desafos da Crítca Textual na era digital, tendo em vista o planeamento de uma edição electrónica de Um buraco na boca
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INTRODUCTION: For a long time, the importance of Chagas disease in Mexico, where many regarded it as an exotic malady, was questioned. Considering the great genetic diversity among isolates of Trypanosoma cruzi, the importance of this biological characterization, and the paucity of information on the clinical and biological aspects of Chagas disease in Mexico, this study aimed to identify the molecular and biological characterization of Trypanosoma cruzi isolates from different endemic areas of this country, especially of the State of Jalisco. METHODS: Eight Mexican Trypanosoma cruzi strains were biologically and genetically characterized (PCR specific for Trypanosoma cruzi, multiplex-PCR, amplification of space no transcript of the genes of the mini-exon, amplification of polymorphic regions of the mini-exon, classification by amplification of intergenic regions of the spliced leader genes, RAPD - (random amplified polymorphic DNA). RESULTS: Two profiles of parasitaemia were observed, patent (peak parasitaemia of 4.6×10(6) to 10(7) parasites/mL) and subpatent. In addition, all isolates were able to infect 100% of the animals. The isolates mainly displayed tropism for striated (cardiac and skeletal) muscle. PCR amplification of the mini-exon gene classified the eight strains as TcI. The RAPD technique revealed intraspecies variation among isolates, distinguishing strains isolated from humans and triatomines and according to geographic origin. CONCLUSIONS: The Mexican T. cruzi strains are myotrophic and belong to group TcI.
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INTRODUCTION: During histoplasmosis, Histoplasma capsulatum soluble antigens (CFAg) can be naturally released by yeast cells. Because CFAg can be specifically targeted during infection, in the present study we investigated CFAg release in experimental murine histoplasmosis, and evaluated the host humoral immune response against high-molecular-mass antigens (hMMAg. >150 kDa), the more immunogenic CFAg fraction. METHODS: Mice were infected with 2.2x10(4) H. capsulatum IMT/HC128 yeast cells. The soluble CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg circulating immune complexes (CIC) levels were determined by enzymelinked immunosorbent assay, at days 0, 7, 14, and 28 post-infection. RESULTS: We observed a progressive increase in circulating levels of CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg CIC after H. capsulatum infection. The hMMAg showed a high percentage of carbohydrates and at least two main immunogenic components. CONCLUSIONS: We verified for the first time that hMMAg from H. capsulatum IMT/HC128 strain induce humoral immune response and lead to CIC formation during experimental histoplasmosis.
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The assessment of wind energy resource for the development of deep offshore wind plants requires the use of every possible source of data and, in many cases, includes data gathered at meteorological stations installed at islands, islets or even oil platforms—all structures that interfere with, and change, the flow characteristics. This work aims to contribute to the evaluation of such changes in the flow by developing a correction methodology and applying it to the case of Berlenga island, Portugal. The study is performed using computational fluid dynamic simulations (CFD) validated by wind tunnel tests. In order to simulate the incoming offshore flow with CFD models a wind profile, unknown a priori, was established using observations from two coastal wind stations and a power law wind profile was fitted to the existing data (a=0.165). The results show that the resulting horizontal wind speed at 80 m above sea level is 16% lower than the wind speed at 80 m above the island for the dominant wind direction sector.
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A potentially renewable and sustainable source of energy is the chemical energy associated with solvation of salts. Mixing of two aqueous streams with different saline concentrations is spontaneous and releases energy. The global theoretically obtainable power from salinity gradient energy due to World’s rivers discharge into the oceans has been estimated to be within the range of 1.4-2.6 TW. Reverse electrodialysis (RED) is one of the emerging, membrane-based, technologies for harvesting the salinity gradient energy. A common RED stack is composed by alternately-arranged cation- and anion-exchange membranes, stacked between two electrodes. The compartments between the membranes are alternately fed with concentrated (e.g., sea water) and dilute (e.g., river water) saline solutions. Migration of the respective counter-ions through the membranes leads to ionic current between the electrodes, where an appropriate redox pair converts the chemical salinity gradient energy into electrical energy. Given the importance of the need for new sources of energy for power generation, the present study aims at better understanding and solving current challenges, associated with the RED stack design, fluid dynamics, ionic mass transfer and long-term RED stack performance with natural saline solutions as feedwaters. Chronopotentiometry was used to determinate diffusion boundary layer (DBL) thickness from diffusion relaxation data and the flow entrance effects on mass transfer were found to avail a power generation increase in RED stacks. Increasing the linear flow velocity also leads to a decrease of DBL thickness but on the cost of a higher pressure drop. Pressure drop inside RED stacks was successfully simulated by the developed mathematical model, in which contribution of several pressure drops, that until now have not been considered, was included. The effect of each pressure drop on the RED stack performance was identified and rationalized and guidelines for planning and/or optimization of RED stacks were derived. The design of new profiled membranes, with a chevron corrugation structure, was proposed using computational fluid dynamics (CFD) modeling. The performance of the suggested corrugation geometry was compared with the already existing ones, as well as with the use of conductive and non-conductive spacers. According to the estimations, use of chevron structures grants the highest net power density values, at the best compromise between the mass transfer coefficient and the pressure drop values. Finally, long-term experiments with natural waters were performed, during which fouling was experienced. For the first time, 2D fluorescence spectroscopy was used to monitor RED stack performance, with a dedicated focus on following fouling on ion-exchange membrane surfaces. To extract relevant information from fluorescence spectra, parallel factor analysis (PARAFAC) was performed. Moreover, the information obtained was then used to predict net power density, stack electric resistance and pressure drop by multivariate statistical models based on projection to latent structures (PLS) modeling. The use in such models of 2D fluorescence data, containing hidden, but extractable by PARAFAC, information about fouling on membrane surfaces, considerably improved the models fitting to the experimental data.
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INTRODUCTION: Amphotericin B, azole or sulfamide drugs are used for treatment of patients with paracoccidioidomycosis. Among the azole drugs, voriconazole was active in vitro against Paracoccidioides brasiliensis and showed efficacy in the treatment of patients infected with this fungus.In the present study the antifungal activity of voriconazole and of other drugs was compared in a rat model of paracoccidioidomycosis. METHODS: Wistar rats were inoculated intravenously with the BOAS strain of P. brasiliensis and antifungal drugs were administered to the animals by gavage at the following doses (mg/kg weight/day): voriconazole (5 to 20), ketoconazole (12 to 15), fluconazole (6), itraconazole (4), and sulfamethoxazole-trimethoprim (120 to 150). The antifungal activity of the drugs was assessed by determining the P. brasiliensis colony forming units in the lungs and spleen of the animals at the end of treatment and by a survival study. RESULTS: Voriconazole reduced the total tissue fungal burden of P. brasiliensis, particularly at doses of ≥10mg/kg weight/day but its antifungal activity was less intense than that of fluconazole, itraconazole and sulfamethoxazole-trimethoprim. The mean survival of animals treated with the last three drugs, 29.1±10.7, 26.1± 10.1 and 28.4±9.6 days, respectively, was higher than that achieved with voriconazole 10mg/kg weight/day (18.5±8.3 days) and that observed in untreated animals (15.7±3.6 days). CONCLUSIONS: At doses similar to those used for clinical treatment, voriconazole showed lower antifungal activity in experimental rat paracoccidioidomycosis than that obtained with itraconazole and sulfamethoxazole-trimethoprim.
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Earthen plastering mortars are becoming recognized as highly eco-efficient. The assessment of their technical properties needs to be standardized but only the German standard DIN 18947 exists for the moment. An extended experimental campaign was developed in order to assess multiple properties of a ready-mixed earth plastering mortar and also to increase scientific knowledge of the influence of test procedures on those properties. The experimental campaign showed that some aspects related to the equipment, type of samples and sample preparation can be very important, while others seemed to have less influence on the results and the classification of mortars. It also showed that some complementary tests can easily be performed and considered together with the standardized ones, while others may need to be improved. The plaster satisfied the requirements of the existing German standard but, most importantly, it seemed adequate for application as rehabilitation plaster on historic and modern masonry buildings. Apart from their aesthetic aspect, the contribution of earthen plasters to eco-efficiency and particularly to hygrometric indoor comfort should be highlighted.
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O presente estudo experimental pretende avaliar o comportamento da aderência entre varões em aço nervurado e o betão, a influência da geometria, do estado de fendilhação do betão e da presença de um varão transversal na zona de ancoragem, no comportamento desta. O bom desempenho das estruturas de betão armado depende da sua ligação e aderência entre os diferentes materiais utilizados na sua conceção, aço e betão. Foi com esse pressuposto que a presente dissertação avançou, de forma a serem estudadas as diversas geometrias e condições a que podem estar sujeitas as ancoragens. Para isso, foram elaborados e ensaiados dezasseis modelo de ancoragem: seis modelos em betão fendilhado e dez modelos em betão não fendilhado. Do estudo experimental desenvolvido, os resultados obtidos em betão não fendilhado dos ensaios de arrancamento “Pull-Out” são comparados com as recomendações NP EN 1992-1-1 [27], fib Model Code 2010 [14] e o Structural Concrete Building Code ACI 318-11 [4]. No presente estudo experimental também foi analisado o efeito da fendilhação do betão, permitindo assim compreender melhor o funcionamento e a resistência de uma ancoragem sujeita a essa situação. O efeito da presença de um varão transversal aplicado na zona do mandril foi também estudado.
Resumo:
Introduction This study assessed the viability of the rabies virus in the argasid tick Carios fonsecai following experimental infection. Methods The mouse inoculation test (MIT), fluorescent antibody test (FAT) and polymerase chain reaction (PCR) were used. The rabies virus was administered to ticks via the intra-coelomic route, and the ticks were sacrificed at different time points. Results The inoculated ticks were negative for rabies according to the MIT. Ticks macerated with rabies virus were positive according to the MIT and FAT. All of the tick lots tested by PCR were positive. Conclusions The rabies virus became unviable shortly after its inoculation into tick bodies. Ticks are not likely to play an important role in the epidemiology of rabies.
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A União Europeia tem dado cada vez mais enfoque à eficiência energética nos edifícios e à sua capacidade de produção de energia, tendo lançado a directiva “Energy Performance of Buildings Directive” com o intuito de que até 31 de Dezembro de 2018 todos os edifícios novos sejam “nZEB-nearly Zero Energy Building”, o que significa que devem por um lado diminuir o seu consumo energético, aumentando a sua eficiência, e por outro lado produzir localmente e através de fontes de energias renováveis toda, ou quase toda, a energia de que necessitam. A presente tese está integrada no Projecto “Frame – Prefabricated systems (modules) for low-energy buildings: design, prototyping and testing” (Ref: PTDC/AURAQI-AQI/117782/2010) que está a ser desenvolvido na Unidade de Eficiência Energética do Laboratório Nacional de Energia e Geologia (LNEG). Neste trabalho é desenvolvido e analisado um sistema BIPV/T-PCM (Building Integrated Photovoltaic Thermal – Phase Change Materials) que engloba todo um novo conceito de captação, armazenamento e gestão da energia solar em fachadas. Este sistema é composto por um módulo fotovoltaico, uma bateria de PCM (Materiais de Mudança de Fase) e todo um sistema de fluxo de ar que permite a gestão da energia colectada e armazenada. Foi também desenvolvido teoricamente um código de gestão energética para a manipulação do sistema. O sistema em estudo apoia-se em três objectivos principais: aquecer no inverno; arrefecer no verão; e aumentar a eficiência do PV arrefecendo-o. Na sequência do trabalho realizado verificou-se que o conceito do sistema em estudo alcança alguns dos objectivos propostos, tendo ainda potencial para se continuar o seu desenvolvimento. O sistema em estudo é um sistema inovador, e como tal está a ser registada uma patente com base no conceito desenvolvido.