80 resultados para Fração idea


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The critically endangered black-faced lion tamarin, Leontopithecus caissara, has a restricted geographical distribution consisting of small mainland and island populations, each with distinct habitats in coastal southeastern Brazil. Necessary conservation management actions require an assessment of whether differences in habitats are reflected in use of space by the species. We studied two tamarin groups on the mainland at Sao Paulo state between August 2005 and March 2007, and compared the results with data from Superagui Island. Three home range estimators were used: minimum convex polygon (MCP), Kernel, and the new technique presented dissolved monthly polygons (DMP). These resulted, respectively, in home ranges of 345, 297, and 282 ha for the 12-month duration of the study. Spatial overlap of mainland groups was extensive, whereas temporal overlap was not, a pattern that indicates resource partitioning is an important strategy to avoid intraspecific competition. L. caissara large home ranges seem to be dynamic, with constant incorporation of new areas and abandonment of others through time. The main difference between mainland and island groups is the amount and variety of sleeping sites. A better understanding of the home range sizes, day range lengths, and territorial behavior of this species will aid in developing better management strategies for its protection. Additionally, the presented DMP protocol is a useful improvement over the MCP method as it results in more realistic home range sizes for wildlife species. Am. J. Primatol. 73: 1114-1126, 2011. (C) 2011 Wiley Periodicals, Inc.

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Prostate growth and physiology are regulated by steroid hormones and modulated by multiple endocrine factors We investigated the action of insulin on the tissue organization and kinetics of epithelial cells in the rat ventral prostate (VP) in response to castration up to 120 hours after surgery by using an acute protocol of alloxan induced diabetes Diabetes caused a reduction in volume density (Vv(o)/) and volume of the epithelium The effects of castration on the epithelium were accelerated in the diabetic animals as determined by changes in V(o)/, and volume The smooth muscle cells became atrophic and apparently relaxed in response to castration in contrast to the spinous aspect observed in nondiabetic castrated rats Counting of apoptotic nuclei in the epithelium showed the classical apoptosis peak at 72 hours in nondiabetic rats and an advance of the apoptosis peak to 48 hours after castration in diabetic rats Insulin restored the time of the peak to 72 hours These results were confirmed after immunostaining for cleaved caspase 3 and suggest a survival and antiapoptotic effect on VP epithelial cells in both the presence and absence of androgen stimulation This idea is supported by the observation that insulin also reduced the overall rate of apoptosis at all experimental points analyzed before and after castration

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We report the first estimate of jaguar density in the semi-arid caatinga biome of north-eastern Brazil. During August-October 2007, in the Serra da Capivara National Park, we used camera traps to identify and count jaguars. Jaguar abundance and density were calculated using mark-recapture models. In a sampling effort of 1,249 camera-trap-nights we identified 12 adult jaguars and estimated an 2 abundance of 14 +/- 3.6 jaguars in an area of 524 km(2), i.e. a density of 2.67 +/- 1.00 jaguars per 100 km(2). This estimate is higher than in most other Brazilian biomes and indicates Serra da Capivara National Park as an important reserve for protecting jaguars in north-eastern Brazil.

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Polymicrogyria (PMG) is a malformation of cortical development characterized by an excessive number of small gyri and abnormal cortical lamination, giving the cortical surface an irregular and gross appearance. The severity of clinical manifestations correlates with the extent of cortical involvement. The objective of the present study was to describe three families with linguistic features of developmental language disorder and reading impairment, and to establish a neuroanatomic correlation through neuroimaging. Subjects have been submitted to a comprehensive protocol including psychological assessment, language evaluation, neurological examination, and neuroimaging investigation. In our families, children usually had the diagnosis of developmental language disorder while adults had the diagnosis of reading impairment. MRI showed perisylvian polymicrogyria in several subjects of each family. Our data support the idea that there is a co-occurrence of developmental language disorder and reading impairment and both conditions may be associated with polymicrogyria. (c) 2007 Elsevier B.V. All rights reserved.

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Objectives: Up-regulated matrix metalloproteinases may be involved in the development of cardiomyocyte injury and the degradation of troponin associated with acute pulmonary thromboembolism. We examined whether pretreatment with doxycycline (a nonspecific matrix metalloproteinase inhibitor) protects against cardiomyocyte injury associated with acute pulmonary thromboembolism. Design: Controlled animal study. Setting: University research laboratory. Subjects: Mongrel dogs. Interventions: Anesthetized animals received doxycycline (10 mg/kg intravenously) or saline and acute pulmonary thromboembolism was induced with autologous blood clots injected into the right atrium. Control animals received doxycycline (or saline). Measurements and Main Results: Hemodynamic measurements were performed, and acute pulmonary thromboembolism increased baseline mean pulmonary arterial pressure and pulmonary vascular resistance by approximately 160% and 362%, respectively (both p<.05), 120 mins after acute pulmonary thromboembolism. Pretreatment with doxycycline attenuated these increases (to 125% and 232%, respectively; both p<.05). Although acute pulmonary thromboembolism tended to increase the right ventricle maximum rate of isovolumic pressure development and the maximum rate of isovolumic pressure decay, doxycycline produced no effects on these parameters. Gelatin zymograms of right ventricle showed that acute pulmonary thromboembolism marginally increased matrix metalloproteinase-9 (but not matrix metalloproteinase-2) levels in the right ventricle. A fluorometric assay to assess net matrix metalloproteinase activities showed that acute pulmonary thromboembolism increased matrix metalloproteinase activities in the right ventricle by >100% (p<.05), and this finding was confirmed by in situ zymography of the right ventricle. Doxycycline attenuated acute pulmonary thromboembolism-induced increases in right ventricle matrix metalloproteinase activities. Acute pulmonary thromboembolism induced neutrophil accumulation in the right ventricle, as estimated by myeloperoxidase activity, and doxycycline blunted this effect (p<.05). Serum cardiac troponin I concentrations, which reflect cardiomyocyte injury, increased after acute pulmonary thromboembolism, and this increase was attenuated by pretreatment with doxycycline (p<.05). Conclusions: We found evidence supporting the idea that acute pulmonary thromboembolism is associated with increased matrix metalloproteinase activities in the right ventricle, which may lead to degradation of sarcomeric proteins, including cardiac troponin I. Inhibition of matrix metalloproteinases may be an effective therapeutic intervention in the management of acute pulmonary thromboembolism. (Crit Care Med 2011; 39: 349-356)