17 research outputs found

    Different infective forms trigger distinct immune response in experimental Chagas disease.

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    Although metacyclic and blood trypomastigotes are completely functional in relation to parasite-host interaction and/or target cell invasion, they differ in the molecules present on the surface. Thus, aspects related to the variability that the forms of T. cruzi interacts with host cells may lead to fundamental implications on the immune response against this parasite and, consequently, the clinical evolution of Chagas disease. We have shown that BT infected mice presented higher levels of parasitemia during all the acute phase of infection. Moreover, the infection with either MT or BT forms resulted in increased levels of total leukocytes, monocytes and lymphocytes, specifically later for MT and earlier for BT. The infection with BT forms presented earlier production of proinflammatory cytokine TNF-α and later of IFN-γ by both T cells subpopulations. This event was accompanied by an early cardiac inflammation with an exacerbation of this process at the end of the acute phase. On the other hand, infection with MT forms result in an early production of IFN-γ, with subsequent control in the production of this cytokine by IL-10, which provided to these animals an immunomodulatory profile in the end of the acute phase. These results are in agreement with what was found for cardiac inflammation where animals infected with MT forms showed intense cardiac inflammation later at infection, with a decrease in the same at the end of this phase. In summary, our findings emphasize the importance of taking into account the inoculums source of T. cruzi, since vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase that may influence relevant biological aspects of chronic Chagas disease

    Resultados a médio prazo do tratamento cirúrgico da dissecção aguda de aorta tipo A com o emprego da prótese intraluminal

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    Introdução: O conceito de prótese intraluminal foi introduzido por CARREL, em 1912. Em 1978, DUREAU & ABLASA descreveram os primeiros casos de dissecção aguda de aorta tratados com o emprego da prótese intraluminal. Esta prótese foi utilizada nos anos 80 por vários grupos com bons resultados. Vários relatos de complicações (migração, embolias, estenoses, formação de pseudo-aneurismas) fizeram com que os grupos cirúrgicos perdessem o entusiasmo por esta técnica. Objetivo: Avaliar a anastomose empregando a prótese intraluminal sem sutura no tratamento da dissecção aguda de aorta tipo A. Casuística e Métodos: Sessenta e quatro pacientes com diagnóstico de dissecção aguda de aorta do tipo A foram operados em nosso Serviço. Em todos os casos empregamos o anel intraluminal como técnica de sutura. A idade média dos pacientes era de 56,3 anos, sendo 57 (89%) do sexo masculino. Todos os pacientes eram portadores de hipertensão arterial sistêmica. Em 26 pacientes utilizamos somente a anastomose intraluminal, com o anel proximal acima dos óstios coronários de modo a ressuspender a valva aórtica e o anel distal posicionado junto à origem do tronco braquiocefálico. O tempo médio de pinçamento da aorta nestes pacientes foi de 9 minutos e o tempo médio de CEC de 26 minutos. Somente em 1 caso houve rotura da ligadura sobre o anel proximal, quando realizamos uma operação radical (Bentall- DeBonno), mantendo o anel distal. Em 23 pacientes utilizamos a ressuspensão da valva aórtica e o preparo da raiz da aorta com duplo retalho de Dacron, empregando o anel intraluminal na anastomose distal. Abordamos o arco aórtico em 8 pacientes. A troca da valva aórtica foi necessária em apenas 6 pacientes. A mortalidade global foi de 10,3%, sendo que nos pacientes onde foi possível o tratamento com o duplo anel não houve nenhum óbito. Na avaliação pós-operatória destes pacientes foi realizado ecocardiograma e aortografia. Não observamos formação de pseudo-aneurisma, migração e o gradiente máximo encontrado foi de 16 mmHg. Conclusão: O emprego da prótese intraluminal para o tratamento da dissecção aguda de aorta do tipo A nos proporciona uma anastomose rápida, segura e hem2ostática. Na avaliação pós-operatória e a médio prazo não observamos qualquer complicação relacionada ao emprego desta técnica

    Resultados a médio prazo do tratamento cirúrgico da dissecção aguda de aorta tipo A com o emprego da prótese intraluminal Surgical treatment of type a aortic dissection using intraluminal prosthesis medium term follow up

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    Introdução: O conceito de prótese intraluminal foi introduzido por CARREL, em 1912. Em 1978, DUREAU & ABLASA descreveram os primeiros casos de dissecção aguda de aorta tratados com o emprego da prótese intraluminal. Esta prótese foi utilizada nos anos 80 por vários grupos com bons resultados. Vários relatos de complicações (migração, embolias, estenoses, formação de pseudo-aneurismas) fizeram com que os grupos cirúrgicos perdessem o entusiasmo por esta técnica. Objetivo: Avaliar a anastomose empregando a prótese intraluminal sem sutura no tratamento da dissecção aguda de aorta tipo A. Casuística e Métodos: Sessenta e quatro pacientes com diagnóstico de dissecção aguda de aorta do tipo A foram operados em nosso Serviço. Em todos os casos empregamos o anel intraluminal como técnica de sutura. A idade média dos pacientes era de 56,3 anos, sendo 57 (89%) do sexo masculino. Todos os pacientes eram portadores de hipertensão arterial sistêmica. Em 26 pacientes utilizamos somente a anastomose intraluminal, com o anel proximal acima dos óstios coronários de modo a ressuspender a valva aórtica e o anel distal posicionado junto à origem do tronco braquiocefálico. O tempo médio de pinçamento da aorta nestes pacientes foi de 9 minutos e o tempo médio de CEC de 26 minutos. Somente em 1 caso houve rotura da ligadura sobre o anel proximal, quando realizamos uma operação radical (Bentall- DeBonno), mantendo o anel distal. Em 23 pacientes utilizamos a ressuspensão da valva aórtica e o preparo da raiz da aorta com duplo retalho de Dacron, empregando o anel intraluminal na anastomose distal. Abordamos o arco aórtico em 8 pacientes. A troca da valva aórtica foi necessária em apenas 6 pacientes. A mortalidade global foi de 10,3%, sendo que nos pacientes onde foi possível o tratamento com o duplo anel não houve nenhum óbito. Na avaliação pós-operatória destes pacientes foi realizado ecocardiograma e aortografia. Não observamos formação de pseudo-aneurisma, migração e o gradiente máximo encontrado foi de 16 mmHg. Conclusão: O emprego da prótese intraluminal para o tratamento da dissecção aguda de aorta do tipo A nos proporciona uma anastomose rápida, segura e hem2ostática. Na avaliação pós-operatória e a médio prazo não observamos qualquer complicação relacionada ao emprego desta técnica.Introduction: The concept of intraluminal prosthesis was introduced by CARREL, in 1912. In 1978, DUREAU & ABLASA described the first case of type A acute aortic dissection treated with intraluminal prosthesis. This prosthesis was used in the eighties by several groups with good results. Several reports of complications (migration, embolism, stenosis, pseudoaneurysms formation) made the surgical groups lose the enthusiasm with that technique. Objective: To evaluate the sutureless anastomosis using the intraluminal prosthesis in the treatment of type A acute aortic dissection. Material and Methods: During the period from July/1996 to November/1999, 64 patients with the diagnosis of type A acute aortic dissection were operated in our Service. In all the cases we used the intraluminal ring as the technique of suture. The average of age was of 56.3 years, and 89% of the patients were males. All the patients had systemic hypertension. In 26 patients we used only the intraluminal anastomosis. The proximal ring was placed above the coronary ostium and the distal ring was positioned close to the origin of the inominate artery. The aorta cross clamping time in these patients was 9 minutes, and the extracorporeal circulation average of time was 26 minutes. Only in 1 case there was a rupture of the ligature on the proximal ring, when we accomplished a radical surgery (Bentall-DeBonno), maintaining the distal ring. In 23 patients we did the aortoplasty and used a double patch of Dacron to prepare the aortic root, using the intraluminal ring in the distal anastomosis. We operated on the aortic arch of 8 patients (without total circulatory arrest, due to selective perfusion of the right subclavian artery). The replacement of the aortic valve was necessary in just 6 patients. The global mortality was of 10.3% and there was no death among the patients which it was possible the treatment with the double ring. As the postoperative evaluation of these patients the echocardiography and the aortography were made. We did not observe pseudoaneurysm formation or migration and the maximum gradient was of 16 mmHg. Conclusion: The employment of the intraluminal prosthesis in the treatment of the type A acute aortic dissection, provides us fast, safe and haemostatic anastomosis, reducing the mortality. In a medium term follow-up we found no complication related to the employment of the intraluminal ring

    Cytokine profile of spleen T-lymphocytes from mice before (0) and at 7, 14, 28 and 42 days after infection with metacyclic (MT) or blood trypomastigotes (BT) of <i>Trypanosoma cruzi</i>.

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    <p>“Gray scale” diagrams were used to represent the cytokine pattern and the cytokine balance within T-cell subsets besides the overall cytokine balance with T-cells, highlighting the predominance of “low” cytokine-producers (white square), “high” TNF-α or IFN-γ producers (black square), “high” IL-10<sup>+</sup> producers (light gray square) or “high” mixed cytokine-producers (dark gray square). Pie charts represent the percentage of animals displaying a given T-cells overall cytokine balance selectively amongst the “high” cytokine-producers. ND = Not detected.</p

    Morphometric analysis and photomicrographs of the area of <i>T. cruzi</i> immunoreactions in the heart at 28 days after mice infection with metacyclic (MT; light gray bar) or blood trypomastigotes (BT; black bar) of <i>Trypanosoma cruzi</i>.

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    <p>Analysis of the area of <i>T. cruzi</i> amastigotes were identified by immunohistochemistry as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032912#s4" target="_blank">Material and Methods</a>. The results are expressed as parasited area ± standard error. Photomicrographs of the heart parasitism demonstrating isolated amastigotes in MT and typical amastigote nests in BT.</p

    Evaluation of a prototype flow cytometry test for serodiagnosis of canine visceral leishmaniasis.

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    Canine visceral leishmaniasis (CVL) is considered one of the most important canine protozoan diseases of zoonotic concern (1). Various species of Phlebotomus and Lutzomyia sandflies are the potential vectors for the pathogenic agent Leishmania infantum (2). In some European, Asian, and African countries and in America, infection in dogs is associated with a risk of human disease (3–5). In Brazil, the Ministry of Health, through the Visceral Leishmaniasis Control and Surveillance Program (VLCSP), has instituted specific measures to reduce morbidity and case fatality rates, including treating human cases, instituting vector control, and, an action that is unique in the world, sacrificing all seropositive/infected dogs and prohibiting the treatment of CVL (6). During the last decade, the criteria for eliminating infected animals were based on enzyme-linked immunosorbent assays (ELISAs) for screening and indirect immunofluorescence antibody tests (IFATs) for the confirmatory diagnosis of CVL (6, 7). That these tests may lead to false-positive results due to crossreactivity with other parasitic diseases is well known (8, 9). Recently, this approach was modified, and testing is now based on a dual-path platform (DPP) for screening and an ELISA for confirmation (10). However, Grimaldi et al. (11) evaluated the DPP test for the serodiagnosis of CVL and showed that it does not perform well in detecting asymptomatic dogs from areas where canine disease is endemic. It has been shown that vaccination with Leishmune may lead to seroconversion in healthy dogs (10). The vaccination of dogs has increasingly become a common practice in areas in Brazil where CVL is endemic; recently, in addition to the Leishmune vaccine, the Leish-Tec vaccine has become available commercially, and new candidates, such as the LBSap vaccine, are being studied (12– 15). In this sense, seroconversion has become an important problem for surveillance/control programs that employ conventional methodologies in their seroepidemiological surveys, because it can lead to the unnecessary euthanasia of healthy dogs. Nevertheless, the role of vaccination in the diagnosis of CVL still has not been studied sufficiently

    FORAGE SORGHUM CULTIVARS PERFORMANCE IN DIFERENT SOIL AND CLIMATE ENVIRONMENTS IN PERNAMBUCO AND ALAGOAS, NORTHEASTERN BRAZIL

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    The main objective of this work was to evaluate 20 forage sorghum varietiesin different environments, being five in Pernambuco and two in Alagoas, to recommendation.The cultivars were evaluated through the plant height, dry matter yield and water use efficiencyparameters. The experimental design was randomized blocks. The variance analyses werecarried out individually for environments, and grouping analyses for Pernambuco and Alagoas separately. The main conclusions were that the dry matter production and water use efficiencyparameters, when associated to each other, seemed to be appropriate for the forage sorghumvarieties selection under semi-arid conditions; the CSF11 and CSF12 varieties presented highperformance in all of Pernambuco and Alagoas environments, when compared to the others
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