21 resultados para 809.814


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Currently, the combination of cisplatin and gemcitabine is considered a standard chemotherapeutic protocol for bladder cancer. However, the mechanism by which these drugs act on tumor cells is not completely understood. The aim of the present study was to investigate the effects of these two antineoplastic drugs on the apoptotic index and cell cycle kinetics of urinary bladder transitional carcinoma cell lines with wild-type or mutant TP53 (RT4: wild type for TP53; 5637 and T24: mutated TP53). Cytotoxicity, cell survival assays, clonogenic survival assays and flow cytometric analyses for cell cycle kinetics and apoptosis detection were performed with three cell lines treated with different concentrations of cisplatin and gemcitabine. G(1) cell cycle arrest was observed in the three cell lines after treatment with gemcitabine and gemcitabine plus cisplatin. A significant increase in cell death was also detected in all cell lines treated with cisplatin or gemcitabine. Lower survival rates occurred with the combined drug protocol independent of TP53 status. TP53-wild type cells (RT4) were more sensitive to apoptosis than were mutated TP53 cells when treated with cisplatin or gemcitabine. Concurrent treatment with cisplatin and gemcitabine was more effective on transitional carcinoma cell lines than either drug alone; the drug combination led to a decreased cell survival that was independent of TP53 status. Therefore, the synergy between low concentrations of cisplatin and gemcitabine may have clinical relevance, as high concentrations of each individual drug are toxic to whole organisms.

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The objective of this study was to evaluate the possible use of biometric testicular traits as selection criteria for young Nellore bulls using Bayesian inference to estimate heritability coefficients and genetic correlations. Multitrait analysis was performed including 17,211 records of scrotal circumference obtained during andrological assessment (SCAND) and 15,313 records of testicular volume and shape. In addition, 50,809 records of scrotal circumference at 18 mo (SC18), used as an anchor trait, were analyzed. The (co) variance components and breeding values were estimated by Gibbs sampling using the Gibbs2F90 program under an animal model that included contemporary groups as fixed effects, age of the animal as a linear covariate, and direct additive genetic effects as random effects. Heritabilities of 0.42, 0.43, 0.31, 0.20, 0.04, 0.16, 0.15, and 0.10 were obtained for SC18, SCAND, testicular volume, testicular shape, minor defects, major defects, total defects, and satisfactory andrological evaluation, respectively. The genetic correlations between SC18 and the other traits were 0.84 (SCAND), 0.75 (testicular shape), 0.44 (testicular volume), -0.23 (minor defects), -0.16 (major defects), -0.24 (total defects), and 0.56 (satisfactory andrological evaluation). Genetic correlations of 0.94 and 0.52 were obtained between SCAND and testicular volume and shape, respectively, and of 0.52 between testicular volume and testicular shape. In addition to favorable genetic parameter estimates, SC18 was found to be the most advantageous testicular trait due to its easy measurement before andrological assessment of the animals, even though the utilization of biometric testicular traits as selection criteria was also found to be possible. In conclusion, SC18 and biometric testicular traits can be adopted as a selection criterion to improve the fertility of young Nellore bulls.

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The high ingestion of oleic (OLA) and linoleic (LNA) acids by Western populations, the presence of inflammatory diseases in these populations, and the importance of neutrophils in the inflammatory process led us to investigate the effects of oral ingestion of unesterified OLA and LNA on rat neutrophil function. Pure OLA and LNA were administered by gavage over 10 days. The doses used (0.11, 0.22 and 0.44 g/kg of body weight) were based on the Western consumption of OLA and LNA. Neither fatty acid affected food, calorie or water intake. The fatty acids were not toxic to neutrophils as evaluated by cytometry using propidium iodide (membrane integrity and DNA fragmentation). Neutrophil migration in response to intraperitoneal injection of glycogen and in the air pouch assay, was elevated after administration of either OLA or LNA. This effect was associated with enhancement of rolling and increased release of the chemokine CINC-2 alpha beta. Both fatty acids elevated l-selectin expression, whereas no effect on beta(2)-integrin expression was observed, as evaluated by flow cytometry. LNA increased the production of proinflammatory cytokines (IL-1 beta and CINC-2 alpha beta) by neutrophils after 4 h in culture and both fatty acids decreased the release of the same cytokines after 18 h. In conclusion, OLA and LNA modulate several functions of neutrophils and can influence the inflammatory process.

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In hypertension, left ventricular (LV) hypertrophy develops as an adaptive mechanism to compensate for increased afterload and thus preserve systolic function. Associated structural changes such as microvascular disease might potentially interfere with this mechanism, producing pathological hypertrophy. A poorer outcome is expected to occur when LV function is put in jeopardy by impaired coronary reserve. The aim of this study was to evaluate the role of coronary reserve in the long-term outcome of patients with hypertensive dilated cardiomyopathy. Between 1996 and 2000, 45 patients, 30 of them male, with 52 +/- 11 years and LV fractional shortening <30% were enrolled and followed until 2006. Coronary flow velocity reserve was assessed by transesophageal Doppler of the left anterior descending coronary artery. Sixteen patients showed >= 10% improvement in LV fractional shortening after 17 +/- 6 months. Coronary reserve was the only variable independently related to this improvement. Total mortality was 38% in 10 years. The Cox model identified coronary reserve (hazard ratio = 0.814; 95% CI = 0.72-0.92), LV mass, low diastolic blood pressure, and male gender as independent predictors of mortality. In hypertensive dilated cardiomyopathy, coronary reserve impairment adversely affects survival, possibly by interfering with the improvement of LV dysfunction. J Am Soc Hypertens 2010;4(1):14-21. (C) 2010 American Society of Hypertension. All rights reserved.

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We derive a closed form expression for the long wavelength limit of the effective action for hard thermal loops in an external gravitational field. It is a function of the metric, independent of time derivatives. It is compared and contrasted with the static limit, and with the corresponding limits in an external Yang-Mills field. (C) 2009 Elsevier B.V. All rights reserved.

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This paper reports the preparation and characterization of poly-{trans-[RuCl(2)(vpy)(4)]-styrene-divinylbenzene} and styrene-divinylbenzene-vinylpiridine filled with nanosilver. Theses materials were synthesized by non aqueous polymerization through a chemical reaction using benzoyl peroxide as the initiator. The nanosilver was obtained from chemical reduction using NaBH(4) as reducing agent and sodium citrate as stabilizer. The nanometric dimension of nanosilver was monitored by UV-visible and confirmed through TEM. The morphology was characterized by SEM and the thermal properties were done by TGA and DSC. The antimicrobial action of the polymers impregnated with nanosilver was evaluated using both microorganisms, Staphylococcus aureus and Escherichia coli. The antimicrobial activity of the poly-{trans-[RuCl(2)(vpy)(4)]-styrene-divinylbenzene} filled with nanosilver was confirmed by the presence of an inhibition halo of the bacterial growth in seeded culture media, but was not confirmed to the styrene-divinylbenzene-vinylpiridine. The present work suggest that trans - [RuCl(2)(vpy)(4)] complex facilitate the release of silver ion from the media.