104 resultados para Anatomy, Pathological.
Swimming training exacerbates pathological cardiac hypertrophy in kinin B(2) receptor-deficient mice
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Kallikrein-kinin system exerts cardioprotective effects against pathological hypertrophy. These effects are modulated mainly via B(2) receptor activation. Chronic physical exercise can induce physiological cardiac hypertrophy characterized by normal organization of cardiac structure. Therefore, the aim of this work was to verify the influence of kinin B(2) receptor deletion on physiological hypertrophy to exercise stimulus. Animals were submitted to swimming practice for 5 min or for 60 min, 5 days a week, during 1 month and several cardiac parameters were evaluated. Results showed no significantly difference in heart weight between both groups, however an increased left ventricle weight and myocyte diameter were observed after the 60 min swimming protocol, which was more pronounced in B(2)(-/-) mice. In addition, sedentary B(2)(-/-) animals presented higher left ventricle mass when compared to wild-type (WT) mice. An increase in capillary density was observed in exercised animals, however the effect was less pronounced in B(2)(-/-) mice. Collagen, a marker of pathological hypertrophy, was increased in B(2)(-/-) mice submitted to swimming protocol, as well as left ventricular thickness, suggesting that these animals do not respond with physiological hypertrophy for this kind of exercise. In conclusion, our data suggest an important role for the kinin B(2) receptor in physiological cardiac hypertrophy. (c) 2007 Elsevier B.V. All rights reserved.
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Heat-shock proteins (HSPs) are currently one of the most promising targets for the development of immunotherapy against tumours and autoimmune disorders. This protein family has the capacity to activate or modulate the function of different immune system cells. They induce the activation of monocytes, macrophages and dendritic cells, and contribute to cross-priming, an important mechanism of presentation of exogenous antigen in the context of MHC class I molecules, These various immunological properties of HSP have encouraged their use in several clinical trials. Nevertheless, an important issue regarding these proteins is whether the high homology among HSPs across different species may trigger the breakdown of immune tolerance and induce autoimmune diseases. We have developed a DNA vaccine codifying the Mycobacterium leprae Hsp65 (DNAhsp65), which showed to be highly immunogenic and protective against experimental tuberculosis. Here, we address the question of whether DNAhsp65 immunization could induce pathological autoimmunity in mice. Our results show that DNAhsp65 vaccination induced antibodies that can recognize the human Hsp60 but did not induce harmful effects in 16 different organs analysed by histopathology up to 210 days after vaccination. We also showed that anti-DNA antibodies were not elicited after DNA vaccination. The results are important for the development of both HSP and DNA-based immunomodulatory agents.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The reproductive system of male Phrynops geoffroanus adults is macroscopically described and the variation in testicular biometry is evaluated. A pair of oval testes is connected by the efferent ductules to the epididymis, which continue as deferent ducts, which emerge in the penis. The volume of the gonads showed the highest averages during spring and summer months. GSI varied significantly throughout the year, with the highest averages observed in the months that correspond to the end of spring and the beginning of summer, when the reproduction of the species takes place, and the lowest averages were seen in winter, suggesting a cyclical testicular activity.
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Flower anatomy, embryology, and seed anatomy are described for some Brazilian species of Xyris section Nematopus and reviewed with respect to the systematic position of Xyris and allied taxa in Commelinanae. Apart from tenuinucellate ovules (shared with Poales, Mayaca, and Eriocaulaceae), Xyris lacks some of the synapomorphies of other genera that are sometimes included in Xyridaceae (Aratitiyopea, Achlyphila, Abolboda, and Orectanthe), such as inaperturate spinulate pollen; Xyris has monosulcate reticulate pollen. There is an unusual degree of variation among different genera of Xyridaceae for characters such as tapetum type, indicating that the monophyly of the family requires testing. However, while several characters indicate two generic groups, there is much missing critical information for embryological and seed coat characters in other Xyridaceae.
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Ensiform leaf development in monocotyledons follows a broadly similar sequence in a wide range of relatively unrelated taxa, indicating a plastic developmental pattern, possibly associated with stressed environmental conditions, since Xyris species tend to grow in relatively damp but nutrient-poor environments. The bifacial leaf sheath surrounds the apex and the subadjacent primordium. A conical unifacial leaf tip 'Vorlauferspitze' is established at an early stage, followed by extension growth in the region behind it, generating a unifacial ensiform blade. Root and rhizome structure are also described in a systematic context, particularly in comparison with related taxa in Xyridaceae and other commelinoid monocotyledons, although information on these structure is relatively sparse.
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Several leaf anatomical features are potentially systematically informative within both the family Vochysiaceae and the order Myrtales, notably tracheoidal idioblasts, mucilage cells and secretory canals. Tracheoids with spiral wall thickenings are present in the mesophyll of most species of Vochysia, and also occur in several other families of Myrtales. Mucilage cells are common in the leaf epidermis in some Vochysiaceae. Secretory ducts are present in the midrib in Salvertia and Vochysia, which are apparently closely related, although Salvertia also shares some leaf anatomical characters with Qualea and Callisthene. Anatomical data do not support the segregation of Ruizterania from Qualea; leaves of R. albiflora leaves are very similar to those of Q. paraensis in venation pattern, and leaf and stem anatomy. Different venation patterns are characteristic of sections within the genus Qualea, but within the large genus Vochysia, leaf anatomy is variable even within a subsection. Amongst other Myrtales, leaf anatomy of Vochysiaceae most closely resembles that of Combretaceae and Onagraceae. © 2002 The Linnean Society of London.
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We report a case of a pleomorphic xantoastrocytoma which manifested itself as a cystic isodense lesion in the right fronto-temporal lobe in a 26 year-old woman. It appeared as a soft yellow tumor with cystic cavities on surgery. Five months after this surgery, the patient was submitted to a new operation, which revealed a friable tumor, easily differentiated from the normal parenchyma, with cystic components. The histopathological examination demonstrated pleomorphic xanthoastrocytoma with malignant transformation. Histologically, the tumor at first procedure was composed of pleomorphic astrocytes with multinucleated and foamy cells. A rare case of malignant transformation in pleomorphic xanthoastrocytoma is presented, discussed and illustrated in this paper.
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The purpose of this study was to show anatomical variations in permanent maxillary molars. Two clinical cases of four-rooted maxillary molars and a macroscopic study of an extracted tooth, showing a five-rooted maxillary molar, are presented.
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Leaves of Artemisia annua L. are a plentiful source of artemisinin, a drug with proven effectiveness against malaria. The aim of this study was to classify the photosynthetic mechanism of A. annua through studies of the carbon isotope composition (δ 13C) and the leaf anatomy. A. annua presented a δ 13C value of - 31.76 ± 0.07, which characterizes the plants as a typical species of the C3 photosynthethic mechanism, considering that the average δ 13C values for C3 and C4 species are -28 and -14, respectively. The leaf anatomy studies were consistent with the δ 13C results, where, in spite of the existence of parenchymatic cells forming a sheath surrounding the vascular tissue, the cells do not contain chloroplasts or starch. This characteristic is clearly different from that of the Kranz anatomy found in C4 species.
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• Background and Aims: Eriocaulaceae (Poales) is currently divided in two subfamilies: Eriocauloideae, which comprises two genera and Paepalanthoideae, with nine genera. The floral anatomy of Actinocephalus polyanthus, Leiothrix fluitans, Paepalanthus chlorocephalus, P. flaccidus and Rondonanthus roraimae was studied here. The flowers of these species of Paepalanthoideae are unisexual, and form capitulum-type inflorescences. Staminate and pistillate flowers are randomly distributed in the capitulum and develop centripetally. This work aims to establish a floral nomenclature for the Eriocaulaceae to provide more information about the taxonomy and phylogeny of the family. • Methods: Light microscopy, scanning electron microscopy and chemical tests were used to investigate the floral structures. • Key Results: Staminate and pistillate flowers are trimerous (except in P. flaccidus, which presents dimerous flowers), and the perianth of all species is differentiated into sepals and petals. Staminate flowers present an androecium with scale-like staminodes (not in R. roraimae) and fertile stamens, and nectariferous pistillodes. Pistillate flowers present scale-like staminodes (except for R. roraimae, which presents elongated and vascularized staminodes), and a gynoecium with a hollow style, ramified in stigmatic and nectariferous portions. • Conclusions: The scale-like staminodes present in the species of Paepalanthoideae indicate a probable reduction of the outer whorl of stamens present in species of Eriocauloideae. Among the Paepalanthoideae genera, Rondonanthus, which is probably basal, shows vascularized staminodes in their pistillate flowers. The occurrence of nectariferous pistillodes in staminate flowers and that of nectariferous portions of the style in pistillate flowers of Paepalanthoideae are emphasized as nectariferous structures in Eriocaulaceae. © The Author 2006. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)