54 research outputs found

    Texture and magnetic properties improvement of a 3% Si non-oriented electrical steel by Sb addition.

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    The influence of small antimony addition and thermomechanical processing on the magnetic properties of a 3% Si steel was investigated. The samples were processed in the laboratory with 930 1C hot rolling finishing temperature, three different hot band thicknesses, hot band annealing at 1030 1C, cold rolling with three different reductions to 0.35 mm thickness and final annealing at 1030 1C. The results have shown that the best combination of core loss and magnetic induction can be obtained by Sb content of 0.045% and 76% cold rolling reduction, and that Eta/Gamma ratio is higher and grain size larger at this Sb content

    Anti-serum validation for use in immunohistochemistry for Trypanosoma cruzi detection.

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    Introduction: The detection of Trypanosoma cruzi in tissue samples is important in many situations, such as testing of the reactivation of the infection. The detection of T. cruzi nests in endomyocardial biopsies (EMB) may be useful to evaluate graft rejection. Given their scarcity, such nests are not routinely identified. To increase the diagnosis sensitivity, immunohistochemistry (IHC) may serve as a promising strategy. Here, we validate an antiserum for the detection of T. cruzi infection by IHC. Methods: We used 1) positive controls (PCs) ? 13 EMB, 12 skin biopsies, and 1 heart with T. cruzi nests as sections stained with hematoxylin and eosin (HE); 2) negative controls ? a) 10 explant hearts and 10 EMB with no amastigote nests or clinical/laboratory signs of chagasic infection; and b) eight samples with leishmaniasis, toxoplasmosis, or histoplasmosis; and 3) Cases ? 31 EMB of chagasic patients with no parasite nests in HE sections but detected positive for T. cruzi DNA by polymerase chain reaction. As a primary antibody, a hyperimmune serum from T. cruzi-infected rabbits was used. Results: IHC results were positive for 21 of 26 PCs (80.8%) and one case of cutaneous leishmaniasis. In 4 of 31 cases, IHC revealed nests (12.9%), which were undetected by conventional histological examination. Conclusions: This study shows that IHC with the tested antiserum increases the sensitivity of the diagnosis and may be recommended for routine use in EMB analyses of cardiac transplant patients with Chagas disease

    Estabilidade de caracter?sticas f?sico-qu?micas em sucos naturais de cenoura e laranja armazenados sob refrigera??o.

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    O objetivo do estudo foi avaliar o pH, acidez, atividade antioxidante e Vit C e suas estabilidades, durante o armazenamento sob refrigera??o em sucos de cenoura e laranja com suas misturas em propor??es espec?ficas feitas a cada tempo de medida. Cinco formula??es de suco foram preparadas com cenoura-laranja nas propor??es: 100:0 (100C), 25:75 (25C75L), 50:50 (50C50L), 75:25 (75L25) e 0:100 (100L) de sucos de cenoura e laranja, respectivamente. An?lise foi realizada em amostras de sucos em 7 tempos (0 a 12 h). Os valores de pH, acidez titul?vel para os extratos de 100C, 75C25L e 100L mostraram uma estabilidade no per?odo avaliado, e para os extratos de 50C50L e 25C75L houve queda significativa. A atividade antioxidante e Vit C permaneceram constante. Os resultados mostram que o os sucos frescos refrigerados podem ser consumidos ap?s 12 horas sem a perda de sua capacidade antioxidante. No entanto, para uma maior atividade antioxidante, recomenda-se o consumo do suco de laranja.Theobjective of this studywas to evaluate the pH, acidity,antioxidant activity and vit Cand their stabilityduring storageunder refrigerationin juicesof carrot,orange and their mixtures in specific proportions made at any time of measure.Five formulations of juicewere preparedwithcarrot- orange following proportions: 100:0(100C), 25:75(25C75L), 50:50(50C50L), 75:25(75L25) and 0:100 (100L) of carrot and orange juices, respectively. Evaluation was carried out injuices samples in 7times (0 to 12 h). The pH values, titratable acidity for extracts of 100C, 100L and 75C25L showed stability during the study period, and extracts 50C50L and 25C75L showed significant decrease. The antioxidant activity and vitamin C remained constant. The results show that fresh chilled juices can be consumed over a period of 12 hours without loss of their antioxidant capacity. However, for greater antioxidant activity, it is recommended the consumption of orange juice

    Propriedades microbianas e do solo em ?reas em restaura??o no vale do jequitinhonha, Minas Gerais

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    O setor florestal no Alto Vale do Jequitinhonha (MG) tem adotado a cria??o de faixas com vegeta??o nativa entre os seus plantios comerciais, com o objetivo de reduzir os impactos negativos do monocultivo. O m?todo utilizado para cria??o dessas faixas tem sido a restaura??o espont?nea da vegeta??o nativa em ?reas anteriormente cultivadas com eucalipto. O objetivo deste trabalho foi avaliar o efeito de coberturas vegetais sobre propriedades microbianas do solo, para melhor caracterizar o processo de restaura??o da vegeta??o nativa em solos florestais do Vale do Jequitinhonha, MG. Os tratamentos foram: restaura??o inicial (; 4 anos) com ou sem remanescentes de eucalipto; e os controles: plantio comercial de eucalipto, vegeta??o nativa de Cerrado e de mata. As amostras de solo foram coletadas por tr?s anos consecutivos, nos meses de agosto e fevereiro, representando, respectivamente, o per?odo de estiagem e o de chuvas. As ?reas em restaura??o, independentemente da presen?a de eucalipto remanescentes, n?o diferiram quanto a atividade microbiana, exceto para quociente metab?lico (qCO2) em fevereiro de 2007 - per?odo chuvoso. Nessa ?poca, a atividade microbiana foi maior na restaura??o avan?ada sem eucalipto do que na restaura??o inicial sem eucalipto e restaura??o avan?ada com eucalipto. As ?reas em restaura??o, em geral, tamb?m n?o diferiram dos controles: plantio de eucalipto e Cerrado. Em rela??o ao controle mata, as ?reas em restaura??o apresentaram, em geral, menores teores de C org?nico, C microbiano, respira??o basal (Rbasal) e hidr?lise do diacetato de fluoresce?na (FDA), n?o diferindo quanto ao qCO2 e quociente microbiano (qMIC). Em geral, as restaura??es iniciais e avan?adas apresentaram qualidade do solo semelhante. A maioria das propriedades do solo e microbianas, nos tr?s anos avaliados, indicou que as ?reas em restaura??o mostraram maior semelhan?a com a ?rea de Cerrado. Nas ?reas em restaura??o avan?ada sem eucalipto, a menor Rbasal no ano 3 e a menor FDA e qMIC e maior qCO2 no ano 2, em rela??o ao Cerrado, indicaram que a remo??o do eucalipto remanescente n?o promoveu a restaura??o.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)To mitigate the impacts of eucalypt monoculture, forestry companies in the Upper Jequitinhonha Valley (MG) have adopted the insertion of strips of native vegetation in-between the commercial plantations. The method used for the creation of these corridors is to allow spontaneous regrowth of native vegetation in areas previously under eucalypt. The objective of this study was to evaluate the effect of cover crops on microbial and soil properties for a detailed description of the restoration process of native vegetation in forest soils of the Jequitinhonha Valley. The treatments were represented by an initial restoration stage ( 4 years) with or without remaining eucalypt, plus the three controls: commercial eucalypt plantation, Cerrado vegetation and native forest. Soil samples were collected for three consecutive years in the dry and rainy season (August and February, respectively). The microbial activity, regardless of the presence of remaining eucalypt , did not differ among the restoration areas, except for the metabolic quotient (qCO2) in the rainy season of February 2007. At this time, this microbial activity was higher in the advanced restoration stage without eucalypt than initial restoration without eucalypt and advanced restoration with eucalypt. The restoration areas, in general, did not differ from the control: eucalypt plantation and Cerrado either. Compared to the forest, the levels of organic C, microbial C, basal respiration (Rbasal) and hydrolysis of fluorescein diacetate (FDA) in the restoration areas were, in general, lower and did not differ in qCO2 and microbial quotient (qMIC). In general, the soil quality was similar in the initial and advanced restoration stages. Most of the soil and microbial properties in the three years indicated that the restoration areas were most similar to the Cerrado. In the advanced restoration areas without eucalypt compared to Cerrado, the lower Rbasal in the 3rd year and the lower FDA and qMIC and higher qCO2 in the 2nd year indicated that the removal of the remaining eucalypt trees was unfavorable for restoration

    Vaccination with a CD4+ and CD8+ T-cell epitopes-based recombinant chimeric protein derived from Leishmania infantum proteins confers protective immunity against visceral leishmaniasis.

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    Vaccination seems to be the best approach to control visceral leishmaniasis (VL). Resistance against infection is based on the development of a Th1 immune response characterized by the production of interferons-? (IFN-?), interleukin-12 (IL-12), granulocyte-macrophage-colony-stimulating factor (GM-CSF), and tumor necrosis factor-? (TNF-?), among others. A number of antigens have been tested as potential targets against the disease; few of them are able to stimulate human immune cells. In the present study, 1 prediction of MHC class I and II molecules-specific epitopes in the amino acid sequences of 3 Leishmania proteins: 1 hypothetical, prohibitin, and small glutamine-rich tetratricopeptide repeat-containing proteins, was performed using bioinformatics tools, and a T-cell epitopes-based recombinant chimeric protein was constructed, synthetized and purified to be evaluated in invitro and in vivo experiments. The purified protein was tested regarding its immunogenicity in peripheral blood mononuclear cells (PBMCs) from healthy subjects and VL patients, as well as to its immunogenicity and protective efficacy in a murine model against Leishmania infantum infection. Results showed a Th1 response based on high IFN-? and low IL-10 levels derived from in chimera-stimulated PBMCs in both healthy subjects and VL patients. In addition, chimera and/or saponin-immunized mice presented significantly lower parasite burden in distinct evaluated organs, when compared to the controls, besides higher levels of IFN-?, IL-2, IL-12, and GM-CSF, and an IgG2a isotype-based humoral response. In addition, the CD4+ and CD8+ T-cell subtypes contributed to IFN-? production in the protected animals. The results showed the immunogenicity in human cells and the protective efficacy against L. infantum in a murine model, and well indicate that this recombinant chimera can be considered as a promising strategy to be used against human disease

    The antioxidant and anti-inflammatory properties of lycopene in mice lungs exposed to cigarette smoke.

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    Lycopene is a carotenoid with knownantioxidant and anti-inflammatory properties.Weaimed to evaluate the in vitro and in vivo effects of lycopene on reducing the redox imbalance and inflammation induced by cigarette smoke (CS). For the in vitro study, J774A.1 (macrophages) cells were incubated in the presence of 0.5, 1.0, 2.0, 4.0, 8.0, 10.0 and 25 ?Mof lycopene for 3, 6 and 24 h or in the presence of 0.1%, 0.25%, 0.5%, 0.625%, 1.25%, 2.25%, 5% and 10% cigarette smoke extract (CSE) for 3, 6 and 24 h to assess cell viability and measurement of intracellular reactive oxygen species (ROS). For the in vivo study, 40 micewere divided into 5 groups: a control exposed to ambient air (CG), a vehicle-control group that received 200 ?l of sunflower oil by orogastric gavage, a group exposed to CS and two groups administered lycopene (diluted in sunflower oil) at doses of either 25 or 50 mg/kg/day prior to exposure to CS (LY25+CS and LY50+CS). The total treatment time lasted 5 days. A cell viability decreasewas observed at 10- and 25-?Mconcentrations of lycopene in 3, 6 and 24 h compared with CG. Therewas an increase ofROS production in 24 h in CS compared with CG. Lycopene concentrations of 1 ?Mand 2 ?Mwere able to reduce the production of ROS in 24 h comparedwith CS. In the bronchoalveolar lavage fluid, the total number of leukocytes increased in the CS group compared with the control groups (CG). Administrationwith lycopene at the highest dose suppressed this CS-induced increase in leukocytes. Lipid peroxidation and DNA damage increased in the CS group comparedwith that in the controls, and this increase was suppressed by lycopene at the highest dose. In contrast, superoxide dismutase activity decreased in the CS group compared with that in the controls. Catalase activity also increased in the CS group compared with that in both control groups, and this increase was suppressed in LY25+CS and LY50+CS. There was an increase in the levels of tumor necrosis factor-?, interferon-? and interleukin-10 after exposure to CS, and these effects were suppressed by both doses of lycopene. These data elucidate the role of lycopene as an antioxidant and anti-inflammatory agent in these two models of short-term exposure to CS

    Reactive nitrogen/oxygen species production by nitro/nitrosyl supramolecular ruthenium porphyrin complexes.

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    This manuscript reports on new nitro/nitrosyl Ru-based complexes, which were synthesized with the purpose of using them as precursors to obtain supramolecular ruthenium porphyrin species ({TPyP[Ru (NO2)(5,50-Mebipy)2]4}(PF6)4) and ({TPyP[Ru(NO)(5,50-Mebipy)2]4}(PF6)12). The photochemical and photophysical properties of these porphyrin species were investigated. Results show that the complex containing nitrite is able to produce NO by homolytic O?NO cleavage (FPPh NO = 0.05) while the {TPyP[Ru (NO)(5,50-Mebipy)2]4}(PF6)12 does it by direct labilization (FPPh NO = 0.53) of the Ru NO bond. Furthermore, a triplet quantum yield of 0.09 and 0.27 was observed for complexes containing nitrite and nitric oxide, respectively. The reactive oxygen species quantum yield for the complex {TPyP[Ru(NO) (5,50-Mebipy)2]4}(PF6)12 (0.78) is consistent with the sum of quantum yields NO release (0.53) and triplet state (0.27), which suggests that both processes participate in the formation of the reactive species. Our results show that combining these characteristics, NO production and triplet states, on the same platform could induce a synergic effect, leading to a considerable improvement in the photodynamic action of these complexes

    Expression and production of cardiac angiogenic mediators depend on the Trypanosoma cruzi-genetic population in experimental C57BL/6 mice infection.

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    Mammalian cardiac cells are important targets to the protozoan Trypanosoma cruzi. The inflammatory reaction in the host aims at eliminating this parasite, can lead to cell destruction, fibrosis and hypoxia. Local hypoxia iswelldefined stimulus to the production of angiogenesis mediators. Assuming that different genetic T. cruzi populations induce distinct inflammation and disease patterns, the current study aims to investigate whether the production of inflammatory and angiogenic mediators is a parasite strain-dependent condition. C57BL/6 mice were infectedwith the Y and Colombian strains of T. cruzi and euthanized at the 12th and 32nd days, respectively. The blood and heart tissue were processed in immune assays and/or qPCR (TNF, IL-17, IL-10, CCL2, CCL3, CCL5, CCR2, CCR5 and angiogenic factors VEGF, Ang-1, Ang-2) and in histological assays. The T. cruzi increased the inflammatory and angiogenicmediators in the infectedmicewhen theywere compared to non-infected animals.However, the Colombian strain has led to higher (i) leukocyte infiltration, (ii) cardiac TNF and CCL5 production/expression, (iii) cardiac tissue parasitism, and to higher (iv) ratio between heart/body weights. On the other hand, the Colombian strain has caused lower production and expression VEGF, Ang-1 and Ang-2, when it was compared to the Y strain of the parasite. The present study highlights that the T. cruzi-genetic population defines the pattern of angiogenic/inflammatory mediators in the heart tissue, and that itmay contribute to themagnitude of the cardiac pathogenesis. Besides, such assumption opens windows to the understanding of the angiogenic mediator's role in association with the experimental T. cruzi infection

    In vivo antileishmanial efficacy of a naphthoquinone derivate incorporated into a Pluronic? F127-based polymeric micelle system against Leishmania amazonensis infection.

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    New therapeutic strategies against leishmaniasis are desirable, since the treatment against disease presents problems, such as the toxicity, high cost and/or parasite resistance. As consequence, new antileishmanial compounds are necessary to be identified, as presenting high activity against Leishmania parasites, but low toxicity in mammalian hosts. Flau-A is a naphthoquinone derivative recently showed to presents an in vitro effective action against Leishmania amazonensis and L. infantum species. In the present work, the in vivo efficacy of Flau-A, which was incorporated into a Poloxamer 407-based micelle system, was evaluated in a murine model against L. amazonensis infection. Amphotericin B (AmB) and Ambisome? were used as controls. The animals were infected and later treated with the compounds. Thirty days after the treatment, parasitological and immunological parameters were evaluated. Results showed that AmB, Ambisome? , Flau-A or Flau-A/M-treated animals presented significantly lower average lesion diameter and parasite burden in tissue and organs evaluated, when compared to the control (saline and micelle) groups. Flau-A or Flau-A/M-treated mice were those presenting the most significant reductions in the parasite burden, when compared to the others. These animals developed also a more polarized antileishmanial Th1 immune response, which was based on significantly higher levels of IFN-?, IL-12, TNF-?, GM-CSF, and parasite-specific IgG2a isotype; associated with low levels of IL-4, IL10, and IgG1 antibody. The absence of toxicity was found in these animals, although mice receiving AmB have showed high levels of renal and hepatic damage markers. In conclusion, results suggested that the Flau-A/M compound may be considered as a possible therapeutic target to be evaluated against human leishmaniasis
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