915 resultados para lumen
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Evidence of mild hypertension in women and female rats and our preliminary observation showing that training is not effective to reduce pressure in female as it does in male spontaneously hypertensive rats (SHR) prompt us to investigate the effects of gender on hemodynamic pattern and microcirculatory changes induced by exercise training. Female SHR and normotensive controls (Wistar- Kyoto rats) were submitted to training (55% VO2 peak; 3 months) or kept sedentary and instrumented for pressure and hindlimb flow measurements at rest and during exercise. Heart, kidney, and skeletal muscles (locomotor/ nonlocomotor) were processed for morphometric analysis of arterioles, capillaries, and venules. High pressure in female SHR was accompanied by an increased arteriolar wall: lumen ratio in the kidney (+30%; P < 0.01) but an unchanged ratio in the skeletal muscles and myocardium. Female SHR submitted to training did not exhibit further changes on the arteriolar wall: lumen ratio and pressure, showing additionally increased hindlimb resistance at rest (+29%; P < 0.05). On the other hand, female SHR submitted to training exhibited increased capillary and venular densities in locomotor muscles (+50% and 2.3- fold versus sedentary SHR, respectively) and normalized hindlimb flow during exercise hyperemia. Left ventricle pressure and weight were higher in SHR versus WKY rats, but heart performance (positive dP/dt(max) and negative dP/dt(max)) was not changed by hypertension or training, suggesting a compensated heart function in female SHR. In conclusion, the absence of training- induced structural changes on skeletal muscle and myocardium arterioles differed from changes observed previously in male SHR, suggesting a gender effect. This effect might contribute to the lack of pressure fall in trained female SHRs.
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During the rat submandibular gland (SMG) development, organogenesis and cytodifferentiation depend on the actin cytoskeleton, which is regulated by small Rho GTPases. These proteins link cell surface receptors to pathways that regulate cell motility, polarity, gene expression, vesicular trafficking, proliferation and apoptosis. The aim of this study was to evaluate, by immunohistochemistry, the distribution pattern of RhoA, RhoB, RhoC, Rac1 and Cdc42 during cytodifferentiation of the rat SMG and in male adults. All GTPases were found in epithelial and mesenchymal tissues throughout gland development. Rac1 appeared to be important for parenchyma expansion at the beginning of cytodifferentiation, while RhoC, Cdc42 and the inactive phosphorylated form of Rac1 seemed associated with lumen formation and cell polarization in terminal tubules. RhoA and RhoB labeling was evident throughout development. All GTPases were differentially expressed in the adult gland, suggesting that they play specific roles during differentiation and function of the rat SMG.
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Background Along the internal carotid artery (ICA), atherosclerotic plaques are often located in its cavernous sinus (parasellar) segments (pICA). Studies indicate that the incidence of pre-atherosclerotic lesions is linked with the complexity of the pICA; however, the pICA shape was never objectively characterized. Our study aims at providing objective mathematical characterizations of the pICA shape. Methods and results Three-dimensional (3D) computer models, reconstructed from contrast enhanced computed tomography (CT) data of 30 randomly selected patients (60 pICAs) were analyzed with modern visualization software and new mathematical algorithms. As objective measures for the pICA shape complexity, we provide calculations of curvature energy, torsion energy, and total complexity of 3D skeletons of the pICA lumen. We further measured the posterior knee of the so-called ""carotid siphon"" with a virtual goniometer and performed correlations between the objective mathematical calculations and the subjective angle measurements. Conclusions Firstly, our study provides mathematical characterizations of the pICA shape, which can serve as objective reference data for analyzing connections between pICA shape complexity and vascular diseases. Secondly, we provide an objective method for creating Such data. Thirdly, we evaluate the usefulness of subjective goniometric measurements of the angle of the posterior knee of the carotid siphon.
Estudo sobre o software livre comissionado pelo Instituto Nacional da Tecnologia da Informação (ITI)
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Estudo comissionado pelo Instituto Nacional de Tecnologia da Informação ao CTS/FGV Direito Rio, posteriormente convertido no livro "Direito do software livre e a Administraçõa Pública" (Rio de Janeiro: Lumen Juris, 2007). Aborda os seguintes temas: (a) a Constituição e o software livre; (b) aspectos do software livre sob o direito privado; e (c) software livre, Administração Pública e a comunhão do conhecimento informático.
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Obra sob os termos da licença Creative Commons Atribuição-Uso não comercial-Compartilhamento pela mesma licença 2.5.
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A presente obra aborda aspectos teóricos e práticos do domínio público, no Brasil e em outros países, apresentando casos concretos que destacam as complexas questões sociais, econômicas e jurídicas relativas ao tema. O texto repensa o direito autoral brasileiro do ponto de vista do interesse público, do acesso ao conhecimento, do acesso à informação e da produção cultural, e apresenta uma revisão teórica da interface dos direitos autorais com outras áreas do direito civil. O domínio público é aqui estudado em face das mutações provocadas pelo advento da internet, da cultura digital e da democratização do acesso aos meios tecnológicos, propondo-se soluções aos muitos questionamentos que ainda existem acerca da abrangência do instituto e sua regulamentação jurídica.
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OBJECTIVES: To study the effect of short-chain fatty-acids on atrophy and inflammation of excluded colonic segments before and after the development of diversion colitis. INTRODUCTION: Diversion colitis is a chronic inflammatory process affecting the dysfunctional colon, possibly evolving with mucous and blood discharge. The most favored hypotheses to explain its development is short-chain fatty-acid deficiency in the colon lumen. METHODS: Wistar rats were submitted to colostomy with distal colon exclusion. Two control groups (A1 and B1) received rectally administered physiological saline, whereas two experimental groups (A2 and B2) received rectally administered short-chain fatty-acids. The A groups were prophylactically treated (5th to 40th days postoperatively), whereas the B groups were therapeutically treated (after post-operative day 40). The mucosal thickness of the excluded colon was measured histologically. The inflammatory reaction of the mucosal lamina propria and the lymphoid tissue response were quantified through established scores. RESULTS: There was a significant thickness recovery of the colonic mucosa in group B2 animals (p = 0.0001), which also exhibited a significant reduction in the number of eosinophilic polymorphonuclear cells in the lamina propria (p = 0.0126) and in the intestinal lumen (p = 0.0256). Group A2 showed no mucosal thickness recovery and significant increases in the numbers of lymphocytes (p = 0.0006) and eosinophilic polymorphonuclear cells in the lamina propria of the mucosa (p = 0.0022). CONCLUSION: Therapeutic use of short-chain fatty-acids significantly reduced eosinophilic polymorphonuclear cell numbers in the intestinal wall and in the colonic lumen; it also reversed the atrophy of the colonic mucosa. Prophylactic use did not impede the development of mucosal atrophy
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A cutia (Dasyprocta aguti) é um roedor silvestre encontrado amplamente na região Nordeste do Brasil. É uma espécie muito utilizada pela população humana de baixa renda como fonte alternativa de proteína na alimentação. Foram utilizadas 31 cutias, machos, provenientes da Universidade Federal do Piauí (FUFPI), Estado do Piauí e da Escola Superior de Agricultura de Mossoró Estado do Rio Grande do Norte. Os animais foram divididos em grupos etários desde o nascimento até os 14 meses de idade. O diâmetro nuclear médio foi obtido pela medida de 10 núcleos do tipo celular estudado em cada testículo, no estágio 1 do ciclo do epitélio seminífero. Nos animais que não apresentaram o epitélio organizado em estágios bem definidos em virtude da idade, foram feitas medidas em secções transversais escolhidas somente pelo contorno circular. O início da assincronia do processo espermatogênico foi observado a partir dos seis meses de idade. A puberdade, na cutia Dasyprocta aguti, foi definitivamente estabelecida a partir dos nove meses de idade, pois estavam presentes todos os tipos celulares e espermatozóides liberados no lume tubular em grande parte do parênquima testicular.
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Ucides cordatus is the most commercially, important mangrove crab in Brazil. In spite of its economic importance, there are few studies of its reproduction, in particular the female reproductive system. The present study describes the histology and histochemistry of the spermathecae of U. cordatus. Adult females were can lit monthly from July 2004 through June 2005, at Iguape, State of São Paulo. The crabs were anaesthetized, and their spermathecae removed and fixed in Davidson's fluid, following the histological routine for paraffin. The slides were stained with HE, xylidine Ponceau, PAS, alcian blue (pH 1.0 and 2.5), Sudan black B and picrosirius-haematoxylin. Histologically, the spermathecae possesses a capsule of conjunctive tissue, rich in collalgen fibres, which surrounds the secretory columnar epithelium. In the lumen, individual sperm packets are not observed; the spermatophores are intermixed with the seminal fluid and secretions of the spermathecae itself. A large proportion of the free spermatozoids and spermatophores are arranged in homogeneous masses in the proximal part of the spermathecae. The secretion produced by the columnar epithelium appears to promote the movement of the gametes to the fertilization chamber, in a ventral position, allowing fertilization of the oocytes. Histochemically, the secretion produced by the columnar epithelium was strongly positive for neutral polysaccharides, positive for acid polysaccharides, and weakly positive for proteins and lipids. Tills secretion forms a glycoprotein matrix which is associated with maintenance of the spermatophores, which can remain stored for long periods.
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Diversion colitis is a chronic inflammatory process affecting the dysfunctional colon, after a colostomy. It is postulated that nutritional deficiency of the colonic epithelium by the absence of short-chain fatty acids (SCFA) is one of the factors responsible for the appearance of DC and that their employment could reverse the morphological changes of the mucosa. The treatment of choice for fecal diversion colitis (DC) is the reconstruction of the intestinal tract, although they suggested therapeutic options using enemas. This study evaluates the effect of SCFA in atrophy and inflammation in excluded colonic segments before and after the installation DC. Forty Wistar rats were divided into four groups (n = 10 for each group), submitted colostomy with distal colon exclusion. Two control groups (A1 and B1) received rectally administered physiological saline, whereas two experimental groups (A2 and B2) received rectally administered short-chain fatty-acids. The A groups were prophylactically treated (5th to 40th days postoperatively), whereas the B groups were therapeutically treated (after postoperative day 40), for 07 days. Histological sections stained with HE were used for histological analysis of the thickness of the colonic mucosa excluded (t- Student p ≤0.05). Inflammatory reaction of the lamina propria and mucosa were measured with scores previously established (Mann Whitney p ≤ 0.05). There was a significant thickness recovery of the colonic mucosa in group B2 animals (p = 0.0001), which also exhibited a significant reduction in the number of eosinophilic polymorphonuclear cells in the lamina propria (p = 0.0126) and in the intestinal lumen (p = 0.0256). Group A2 did not prevent the mucosal atrophy and significant increases in the numbers of lymphocytes (p=0.0006) and 50 eosinophilic polymorphonuclear cells in the lamina propria of the mucosa (p = 0.0022). Therapeutic use of short-chain fatty-acids significantly reduced eosinophilic polymorphonuclear cell numbers in the intestinal wall and in the colonic lumen; it also reversed the atrophy of the colonic mucosa. Prophylactic use did not impede the development of mucosal atrophy
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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ObjectiveTo compare cardiac output (CO) measured by Doppler echocardiography and thermodilution techniques in spontaneously breathing dogs during continuous infusion of propofol. To do so, CO was obtained using the thermodilution method (CO(TD)) and Doppler evaluation of pulmonary flow (CO(DP)) and aortic flow (CO(DA)).Study designProspective cohort study.AnimalsEight adult dogs weighing 8.3 +/- 2.0 kg.MethodsPropofol was used for induction (7.5 +/- 1.9 mg kg-1 IV) followed by a continuous rate infusion at 0.7 mg kg-1 minute-1. The animals were positioned in left lateral recumbency on an echocardiography table that allowed for positioning of the transducer at the 3rd and 5th intercostal spaces of the left hemithorax for Doppler evaluation of pulmonary and aortic valves, respectively. CO(DP) and CO(DA) were calculated from pulmonary and aortic velocity spectra, respectively. A pulmonary artery catheter was inserted via the jugular vein and positioned inside the lumen of the pulmonary artery in order to evaluate CO(TD). The first measurement of CO(TD), CO(DP) and CO(DA) was performed 30 minutes after beginning continuous infusion (T0) and then at 15-minute intervals (T15, T30, T45 and T60). Numeric data were submitted to two-way anova for repeated measurements, Pearson's correlation coefficient and Bland & Altman analysis. Data are presented as mean +/- SD.ResultsAt T0, CO(TD) was lower than CO(DA). CO(DA) was higher than CO(TD) and CO(DP) at T30, T45 and T60. The difference between the CO(TD) and CO(DP), when all data were included, was -0.04 +/- 0.22 L minute-1 and Pearson's correlation coefficient (r) was 0.86. The difference between the CO(TD) and CO(DA) was -0.87 +/- 0.54 L minute-1 and r = 0.69. For CO(TD) and CO(DP), the difference was -0.82 +/- 0.59 L minute-1 and r = 0.61.ConclusionDoppler evaluation of pulmonary flow was a clinically acceptable method for assessing the CO in propofol-anesthetized dogs.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)