66 resultados para PANEL
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Based on pre-DNA racial/color methodology, clinical and pharmacological trials have traditionally considered the different geographical regions of Brazil as being very heterogeneous. We wished to ascertain how such diversity of regional color categories correlated with ancestry. Using a panel of 40 validated ancestry-informative insertion-deletion DNA polymorphisms we estimated individually the European, African and Amerindian ancestry components of 934 self-categorized White, Brown or Black Brazilians from the four most populous regions of the Country. We unraveled great ancestral diversity between and within the different regions. Especially, color categories in the northern part of Brazil diverged significantly in their ancestry proportions from their counterparts in the southern part of the Country, indicating that diverse regional semantics were being used in the self-classification as White, Brown or Black. To circumvent these regional subjective differences in color perception, we estimated the general ancestry proportions of each of the four regions in a form independent of color considerations. For that, we multiplied the proportions of a given ancestry in a given color category by the official census information about the proportion of that color category in the specific region, to arrive at a ""total ancestry"" estimate. Once such a calculation was performed, there emerged a much higher level of uniformity than previously expected. In all regions studied, the European ancestry was predominant, with proportions ranging from 60.6% in the Northeast to 77.7% in the South. We propose that the immigration of six million Europeans to Brazil in the 19(th) and 20(th) centuries - a phenomenon described and intended as the ""whitening of Brazil"" -is in large part responsible for dissipating previous ancestry dissimilarities that reflected region-specific population histories. These findings, of both clinical and sociological importance for Brazil, should also be relevant to other countries with ancestrally admixed populations.
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Melanoma is a highly aggressive and therapy resistant tumor for which the identification of specific markers and therapeutic targets is highly desirable. We describe here the development and use of a bioinformatic pipeline tool, made publicly available under the name of EST2TSE, for the in silico detection of candidate genes with tissue-specific expression. Using this tool we mined the human EST (Expressed Sequence Tag) database for sequences derived exclusively from melanoma. We found 29 UniGene clusters of multiple ESTs with the potential to predict novel genes with melanoma-specific expression. Using a diverse panel of human tissues and cell lines, we validated the expression of a subset of three previously uncharacterized genes (clusters Hs.295012, Hs.518391, and Hs.559350) to be highly restricted to melanoma/melanocytes and named them RMEL1, 2 and 3, respectively. Expression analysis in nevi, primary melanomas, and metastatic melanomas revealed RMEL1 as a novel melanocytic lineage-specific gene up-regulated during melanoma development. RMEL2 expression was restricted to melanoma tissues and glioblastoma. RMEL3 showed strong up-regulation in nevi and was lost in metastatic tumors. Interestingly, we found correlations of RMEL2 and RMEL3 expression with improved patient outcome, suggesting tumor and/or metastasis suppressor functions for these genes. The three genes are composed of multiple exons and map to 2q12.2, 1q25.3, and 5q11.2, respectively. They are well conserved throughout primates, but not other genomes, and were predicted as having no coding potential, although primate-conserved and human-specific short ORFs could be found. Hairpin RNA secondary structures were also predicted. Concluding, this work offers new melanoma-specific genes for future validation as prognostic markers or as targets for the development of therapeutic strategies to treat melanoma.
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It is well known that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effect of endothelial cell-secreted factors on the phenotype and behavior of tumor cells. The hypothesis underlying this study is that endothelial cells initiate signaling pathways that enhance tumor cell survival and migration. Here, we observed that soluble mediators from primary human dermal microvascular endothelial cells induce phosphorylation of signal transducer and activator of transcription 3 (STAT3), Akt, and extracellular signal-regulated kinase (ERK) in a panel of head and neck squamous cell carcinoma (HNSCC) cells (OSCC-3, UM-SCC-1, UM-SCC-17B, UM-SCC-74A). Gene expression analysis demonstrated that interleukin-6 (IL-6), interleukin-8 (CXCL8), and epidermal growth factor (EGF) are upregulated in endothelial cells cocultured with HNSCC. Blockade of endothelial cell-derived IL-6, CXCL8, or EGF by gene silencing or neutralizing antibodies inhibited phosphorylation of STAT3, Akt, and ERK in tumor cells, respectively. Notably, activation of STAT3, Akt, and ERK by endothelial cells enhanced migration and inhibited anoikis of tumor cells. We have previously demonstrated that Bcl-2 is upregulated in tumor microvessels in patients with HNSCC. Here, we observed that Bcl-2 signaling induces expression of IL-6, CXCL8, and EGF, providing a mechanism for the upregulation of these cytokines in tumor-associated endothelial cells. This study expands the contribution of endothelial cells to the pathobiology of tumor cells. It unveils a new mechanism in which endothelial cells function as initiators of molecular crosstalks that enhance survival and migration of tumor cells.
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Background: Ezetimibe specifically blocks the absorption of dietary and biliary cholesterol and plant sterols. Synergism of ezetimibe-statin therapy on LDL-cholesterol has been demonstrated, but data concerning the pleiotropic effects of this combination are controversial. Objective: This open-label trial evaluated whether the combination of simvastatin and ezetimibe also results in a synergistic effect that reduces the pro-inflammatory status of pre-diabetic subjects. Methods: Fifty pre-diabetic subjects were randomly assigned to one of 2 groups, one receiving ezetimibe (10 mg/day), the other, simvastatin (20 mg/d) for 12 weeks, followed by an additional 12-week period of combined therapy. Blood samples were collected at baseline, 12 and 24 weeks. RESULTS: Total cholesterol, LDL-cholesterol and apolipoprotein B levels decreased in all the periods analyzed (p < 0.01), but triglycerides declined significantly only after combined therapy. Both drugs induced reductions in C-reactive protein, reaching statistical significance after combining ezetimibe with the simvastatin therapy (baseline 0.59 +/- 0.14, simvastatin monotherapy 0.48 +/- 0.12 mg/dL and 0.35 +/- 0.12 mg/dL, p < 0.023). Such a reduction was independent of LDL-cholesterol change. However, mean levels of TNF-alpha and interleukin-6 and leukocyte count did not vary during the whole study. Conclusion: Expected synergistic lowering effects of a simvastatin and ezetimibe combination on LDL-cholesterol, apolipoprotein B and triglycerides levels were confirmed in subjects with early disturbances of glucose metabolism. We suggest an additive effect of this combination also on inflammatory status based on the reduction of C-reactive protein. Attenuation of pro-inflammatory conditions may be relevant in reducing cardiometabolic risk.
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Background: The American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI), revising the National Cholesterol Evaluation Program for Adult Treatment Panel III (NCEP ATP III), and the International Diabetes Federation (IDF) have proposed definitions of metabolic syndrome that take into account waist circumference thresholds according to ethnicity. In this study we estimated the prevalence of metabolic syndrome in a Japanese-Brazilian population using NCEP definitions for Westerners (NCEPwe) and Asians (NCEPas), and IDF for Japanese (IDF). Methods: A total of 650 Japanese-Brazilians living in a developed Brazilian city and aged 30-88 years were included. Results: Metabolic syndrome prevalence according to NCEPwe, NCEPas, and IDF was, respectively, 46.5%, 56.5%, and 48.3%. Only 43.5% of subjects did not have metabolic syndrome by any of the 3 definitions, and 38.3% fulfilled metabolic syndrome criteria for all 3 definitions. Ten percent of subjects were positive for metabolic syndrome based on NCEPas and IDF, but not for NCEPwe. Because IDF requires abdominal obesity as a criterion, the frequency of subjects without metabolic syndrome according to IDF, but with metabolic syndrome by NCEPwe and NCEPas was 8.2%. Conclusions: Independent of the metabolic syndrome definition, Japanese-Brazilians present an elevated metabolic syndrome prevalence, which was higher when using NCEP criteria for Asians, followed by the IDF definition for Japanese.
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Lellis-Santos C, Giannocco G, Nunes MT. The case of thyroid hormones: how to learn physiology by solving a detective case. Adv Physiol Educ 35: 219-226, 2011; doi:10.1152/advan.00135.2010.Thyroid diseases are prevalent among endocrine disorders, and careful evaluation of patients' symptoms is a very important part in their diagnosis. Developing new pedagogical strategies, such as problem-based learning (PBL), is extremely important to stimulate and encourage medical and biomedical students to learn thyroid physiology and identify the signs and symptoms of thyroid dysfunction. The present study aimed to create a new pedagogical approach to build deep knowledge about hypo-/hyperthyroidism by proposing a hands-on activity based on a detective case, using alternative materials in place of laboratory animals. After receiving a description of a criminal story involving changes in thyroid hormone economy, students collected data from clues, such as body weight, mesenteric vascularization, visceral fat, heart and thyroid size, heart rate, and thyroid-stimulating hormone serum concentration to solve the case. Nevertheless, there was one missing clue for each panel of data. Four different materials were proposed to perform the same practical lesson. Animals, pictures, small stuffed toy rats, and illustrations were all effective to promote learning, and the detective case context was considered by students as inviting and stimulating. The activity can be easily performed independently of the institution's purchasing power. The practical lesson stimulated the scientific method of data collection and organization, discussion, and review of thyroid hormone actions to solve the case. Hence, this activity provides a new strategy and alternative materials to teach without animal euthanization.
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This article analyzes the Brazilian political system from the local perspective. Following Cox (1997), we review the problems with electoral coordination that emerge from a given institutional framework. Due to the characteristics of the Brazilian Federal system and its electoral rules, linkage between the three levels of government is not guaranteed a priori, but demands a coordinating effort by the parties' leadership. According to our hypothesis, the parties are capable of coordinating their election strategies at different levels in the party system. Regression models based on two-stage least squares (2SLS) and TOBIT, analyzing a panel of Brazilian municipalities with data from the 1994 and 2000 elections, show that the proportion of votes received by a party in a given election correlates closely with its previous votes in majoritarian elections. Despite institutional incentives, the Brazilian party system shows evidence that it is organized nationally to the extent that it links the competition for votes at the three levels of government (National, State, and Municipal).
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Glyoxalated soy flour adhesives for wood particleboard added with a much smaller proportion of glyoxalated lignin or tannin and without any addition of either formaldehyde or formaldehyde-based resin are shown to yield results satisfying the relevant standard specifications for interior wood boards. Adhesive resin formulations in which the total content of natural material is either 70 or 80% of the total resin solids content gave good results. The resins comprising 70% by weight of natural material can be used in a much lower proportion on wood chips and can afford pressing times fast enough to be significant under industrial panel pressing conditions. The best formulation of all the ones tried was the one based on glyoxalated precooked soy flour (SG), to which a condensed tannin was added in water solution and a polymeric isocyanate (pMDI), where the proportions of the components SG/T/pMDI was 54/16/30 by weight. (C) 2008 Wiley Periodicals, Inc.
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This paper presents an improved constitutive equation of frame in the context of continuous medium technique. This improved constitutive equation, which is a consistent formulation of column global bending, is applicable to a complete class of frameworks including the ideal shear frame panel, for which the beams are assumed to be rigid, and the associated column system, for which the rigidity of beams is negligible. Global buckling and second-order effects of the frame structure are discussed. The main results can be extended to other types of lateral stiffening elements as built-up columns. A worked example is presented in order to compare the main results with those obtained by the classic matrix method. Copyright (C) 2007 John Wiley & Sons, Ltd.
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Minimal pasteurization of orange juice (OJ) consists of using minimum holding time and temperature to ensure partial inactivation of pectin methylesterase (PME). This process produces juice with preserved sensory attributes and has a better acceptance by consumers when compared with commercially pasteurized OJ. Sensory profile and physical-chemical characteristics of minimally processed OJ was determined, during refrigerated storage, for two OJ blends with different pH values and the same level of PME thermal inactivation. A selected and trained sensorial panel (n = 16) performed sensory analysis, based on a quantitative descriptive analysis, twice a week for 30 days, evaluating the attributes of appearance (suspended particles and color intensity), odor (natural orange and fermented orange) and flavor (orange characteristic, fermented orange, acid and bitter taste). Storage presented great effect on OJ sensory profile; however, it was not noticeable on physical-chemical characteristics.
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This article presents a statistical model of agricultural yield data based on a set of hierarchical Bayesian models that allows joint modeling of temporal and spatial autocorrelation. This method captures a comprehensive range of the various uncertainties involved in predicting crop insurance premium rates as opposed to the more traditional ad hoc, two-stage methods that are typically based on independent estimation and prediction. A panel data set of county-average yield data was analyzed for 290 counties in the State of Parana (Brazil) for the period of 1990 through 2002. Posterior predictive criteria are used to evaluate different model specifications. This article provides substantial improvements in the statistical and actuarial methods often applied to the calculation of insurance premium rates. These improvements are especially relevant to situations where data are limited.
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Robust and accurate regional estimates of C storage in soils are currently an important research topic because of ongoing debate about human-induced changes in the terrestrial C cycle. Widely available geoprocessing tools were applied to estimate native soil organic C (SOC) stocks of Rio Grande do Sul state in southern Brazil to a depth of 30 cm from previously sampled soil pedons under undisturbed vegetation. The study used a statewide comprehensive soil survey comprising a small-scale soil map, a climate map, and a soil pedon database. Soil organic C stocks under native vegetation were calculated with two different approaches: the Tier 1 method of the Intergovernmental Panel on Climate Change (IPCC) and a refined method based on actual field measurements derived from soil profile data. Highest SOC stocks occurred in Neossolos Quartzarenico hidromorfico (Aquents), Organossolos Tiomorficos (Hemists), Latossolos Brunos (Udox), and Vertissolos Ebanicos (Uderts) soil classes. Before human use of soils, most C was stored in the Latossolos Vermelhos (Udox) and Neossolos Regoliticos (Orthents), which occupy a large area of Rio Grande do Sul. Generally, IPCC default reference SOC stocks compared well with SOC stocks calculated from soil pedons. The total SOC stock of Rio Grande do Sul was estimated at 1510.3 Tg C (5.8 kg C m(-2)) by the IPPC method and 1597.5 +/- 363.9 Tg C (7.4 +/- 1.9 kg C m(-2)) calculated from soil pedons. The SOC digital map and SOC database developed in this study provide crucial background information for state-level contemporary assessment of C stocks and soil C sequestration programs and initiatives.
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BACKGROUND: The interaction between lipoxygenase-active soybean flour (LOX) and ascorbic acid (AA), on colour, rheological and sensory properties of wheat bread was studied with the aim of reducing the applied quantity of additives in bread formulations. RESULTS: The ascorbic acid (0-500 ppm) and active soybean flour (0-1%) mixture improved bread-crumb colour by lowering the yellow hue in a higher proportion than those expressed by the components alone, characterising a synergistic mechanism ((y) over cap (b) = 15.1- (1.7 x LOX) - (0.5 x AA) - (5.8 x LOX x AA), where : (y) over cap (b) represent the estimated value for the yellow hue parameter). No differences in flavour and porosity were seen between the samples. As supported by the instrumental methods, breads made with active soybean flour and ascorbic acid (LOX + AA) had whiter crumbs and were softer and springier than controls as assessed by a trained sensory panel. In summary, the combination of both active soybean flour and ascorbic acid showed synergism, promoting a greater bleaching effect than when used alone. CONCLUSION: These results suggest the potential use of active soybean flour as a synergistic ingredient in the substitution of artificial additives in bread making. Since the interaction on the bleaching response was not linear and active soybean flour showed a higher iron concentration (66.40 +/- 4.23 mu g g(-1)) than non-active soybean flour (52.30 +/- 0.40 mu g g(-1)), more studies are warranted to establish the biochemical mechanisms involved in this interaction. (c) 2007 Society of Chemical Industry.
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Objectives: The resazurin microtitre plate assay (REMA) was evaluated to determine the susceptibility of Mycobacterium tuberculosis to pyrazinamide, and was compared with the broth microdilution method (BMM), the absolute concentration method (ACM) and pyrazinamidase (PZase) determination. Methods: Thirty-four M. tuberculosis clinical isolates (26 susceptible and 8 resistant to pyrazinamide) and reference strains M. tuberculosis H37Rv ATCC 27294 and Mycobacterium bovis AN5 were tested. Results: REMA and BMM showed 100% specificity and sensitivity when compared with ACM; BMM, however, demanded more reading time. The PZase determination assay showed 87.50% and 100% sensitivity and specificity, respectively. Conclusions: All tested methods in this preliminary study showed excellent sensitivity and specificity for the determination of pyrazinamide susceptibility of M. tuberculosis, but REMA was faster, low-cost and easy to perform and interpret. Additional studies evaluating REMA for differentiating pyrazinamide-resistant and-susceptible M. tuberculosis should be conducted on an extended panel of clinical isolates.
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The cooling intensity of topical emulsions added with encapsulated or free menthol was evaluated by a screened and trained panel recruited based on the American Society for Testing and Materials method. A sensory panel composed of 10 trained judges performed the evaluation of samples stored at 22 +/- 2C for 24 h and, after 28 days of storage, at 37.0 +/- 0.5C. The obtained data were analyzed by analysis of variance and Tukey`s test. The results showed an increase of cooling intensity as a function of encapsulated menthol concentration. The opposite was observed in samples added with free menthol, which may have caused sensory fatigue. Storage at 37 +/- 0.5C for 28 days had no impact on the cooling intensity of emulsions containing encapsulated menthol, demonstrating high stability and suggesting its application in cooling skin care products. In contrast, emulsions added with free menthol showed a drastic decrease of cooling intensity at 37 +/- 0.5C..