955 resultados para Sinais agonísticos


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Ce travaille de dissertation (Master) est le résultat de trois ans de travaille auprès de Mirandas, endroit situé à 22 kilomètres de la ville de Caraúbas, région ouest de l Etat du Rio Grande do Norte. Pendant cette période, on a compris que les habitants de Mirandas se identifient et sont identifiés pour les autres comme des caboclos , catégorie de classification que dans le discours courant, soit à Mirandas ou dans la siège de la municipalité, a des rapports avec la vision que les tous premiers habitants de Mirandas sont venus de la ville du Cabo , dans l Etat de Pernambuco. Et pourtant ; l usage qu a été fait de cette version a fini pour cacher des éléments qui ont défini l identité de Mirandas, tel comme la probable descendance indigène que parfois est actionnée dans les narratives qui montrent des rapports entre les portugais et des femmes indiens qu ont été pris à casco de cavalo (cheval) . (MACÊDO, 2010; CAVIGNAC, 2003). Donc, cette ethnographie porte à la lumière des éléments que sont utilisés pour les mirandenses pour définir leur identité. Cette identité peut être bien visualisé a partir des éléments que les caboclos font des signes diacritiques (BARTH, 1998; OLIVEIRA, 1976), bien comme des rapports établis entre les habitants de Mirandas et ces de Caraúbas. Des rapports qui ont rendu possible les manifestations d affinité et de conflits et que, donc, nous aide à entendre comme cette identité se réactualise dans ces rapports d union et opposition que les mirandenses construisent avec les caraubenses. Cela arrive dans les rapports territoriaux, économiques et de façon plus marquante, dans les rapports religieux.

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Marine algae are one of the major sources of biologic compounds. In extracellular matrix of these organisms there are sulfated polysaccharides that functions as structural components and provides protection against dehydration. The fraction 1.0 (F1.0) rich in sulfated galactans obtained from red seaweed Hypnea musciformis was physicochemical characterized and evaluated for pharmacologic activity through antioxidant activity, cytotoxic action on erythrocytes, anticoagulant, stimulatory action under antithrombotic heparan sulfate synthesis and their effects on cell proliferation and cycle cell progression. The main components of F1.0 were carbohydrates (49.70 ± 0.10%) and sulfate (44.59 ± 0.015%), presenting phenolic compounds (4.79 ± 0.016%) and low protein contamination (0.92 ± 0.001%). Fraction 1.0 showed polidisperse profile and signs in infrared analysis in 1262, 1074 and 930, 900 and 850 attributed to sulfate esters S=O bond, presence of a 3,6- anidrogalactose C-O bond, non-sulfated β-D-galactose and a C-O-SO4 bond in galactose C4, respectively. The fraction rich in sulfated galactans exhibited strong antioxidant action under lipid peroxidation assay with IC50 of 0.003 mg/mL. Besides the inhibition of hemolysis induced by H2O2 in erythrocytes treated with F1.0, this fraction did not promote significant cytotoxity under erythrocytes membranes. F1.0 exhibited low anticoagulant activity causing moderate direct inhibition of enzimatic activity of thrombin. This fraction promoted stimulation around of 4.6 times on this synthesis of heparan sulfate (HS) by rabbit aortic endothelial cells (RAEC) in culture when was compared with non treated cells. The fraction of this algae displayed antiproliferative action under RAEC cells causing incresing on cell number on S fase, blocking the cycle cell progression. Thus F1.0 presented cytostatic and no cytotoxic action under this cell lineage. These results suggest that F1.0 from H. musciformis have antioxidant potential which is a great effect for a compound used as food and in food industry which could be an alternative to food industry to prevent quality decay of lipid containing food due to lipid peroxidation. These polysaccharides prevent the lipid peroxidation once the fraction in study exhibited strong inhibitory action of this process. Furthermore that F1.0 present strong antithrombotic action promoting the stimulation of antithrombotic HS synthesis by endothelial cells, being important for thrombosis preventing, by its inhibitory action under reactive oxygen species (ROS) in some in vitro methods, being involved in promotion of hypercoagulability state.

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Canine Visceral Leishmania (CVL) is an important zoonotic disease that has a world wide distribution and has a large impact on public health on the American Continent, especially in Brazil, where the nature of endemic diseases in humans affects a large part of the nation. The influence of the prevalence of CVL in the increased rate of human cases in endemic areas and in the unleashing of epidemic outbreaks shows the need for a more profound understanding, that would generate significant advances in the current measures used to control the reservoirs of sickness that are practiced by the Programa Nacional de Vigilância e Controle da Leishmaniose Visceral. The present work describes and compares the clinical-laboratorial and histopathological findings of twenty-three dogs that were naturally infected by Leishmania chagasi, from endemic areas in metropolitan Natal, Rio Grande do Norte, Brazil. These animals, that were selected and given physical and serological exams (IFI and ELISA rK-39), were classified according to the degree of clinical severity and had blood samples drawn (whole blood and serum) for a complete hemogram and a coagulogram to be done as well as biochemical tests for kidney and liver function. The confirmation of infection by L. chagasi was done after the euthanasia of the animals, through the direct demonstration of the parasite in the impression of the spleen and liver crowned with GIEMSA and through a cultivation by means of NNN/Schneider. According to the clinical evaluation, the animals were classified as asymptomatic (7), oligosymptomatic (7) and polysymptomatic (9). Among the animals that were chosen to be autopsied, there were 2 asymptomatic, 3 oligosymptomatic and 3 polysymptomatic, for the purpose of studying their histopathology, having collected fragments of the spleen, liver, kidneys and skin and were fixed in 10% tamponed formol. The comparison between the average parameters of the clinical-laboratory tested animals in the groups was done through the Student t test (a<0.05). The main clinical signals observed were lymphadenomegaly, alopecy, dermatitis, exfoliation, cutaneous ulcers, onicogriphosis and emaciation. The main clinical-laboratorial alterations established, mainly in the polysymptomatic group, were anemia, hyperproteinemia, hyperglobulinemia, alterations in the albumin/globulin ratio and increased ALT activity. Renal alterations were not verified (urea and creatinine levels were normal). Thrombocytopenia was observed in three clinical groups. However, the other indicators of coagulation function (TAP and TTPA) did not have abnormal variations. There were inflammatory infiltrations and leishmania amastigotes in the skin of polysymptomatic dogs, however, they were not found in the skin of asymptomatic animals. Hypertrophy and hyperplasia of the phagocyte mononuclear system, leishmania amastigote parasites were found in the macrophages, extramedullary hematopoiesis and degenerative alterations were detected in the spleen and liver of 8 of the animals submitted to histopathological exams. In accord with these results, it was demonstrated that the expected alterations in the hematological and biochemical parameters in function of their viscerotropic nature of CVL are mainly observed in the more advanced stages of the disease. The absence of inflammatory infiltration and parasite load in the skin suggest that infected animals without symptoms may have an importance irrelevant to the infectiousness of the vector

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The Vitamin E consists of eight chemically homologous forms, designated alpha, beta, gamma and delta tocopherols and tocotrienols. Biologically, the alpha-tocopherol (α-TOH) is the most important. Commercially, are found two types of α-TOH a natural (RRR-alpha-tocopherol) and another synthetic (all-rac-alpha-tocopherol). Both forms are absorbed in the intestine, the liver is a preference in favor of forms 2R, due to transfer protein α-TOH. It has higher affinity to these stereoisomers. Newborns are considered high risk for vitamin E deficiency, mainly premature, these have breast milk as a food source for maintenance of serum α-TOH. Clinical signs such as thrombocytosis, hemolytic anemia, retrolental fibroplasia, intraventricular hemorrhage, bronchopulmonary dysplasia and spinocerebellar degeneration can be found in case of a low intake of α-TOH. Thus, maternal supplementation on postpartum with α-TOH can be an efficient way to increase levels of vitamin E in breast milk and thus the consequently increase the supply of micronutrient for the newborn. However, most studies with vitamin E supplementation have been conducted in animals and little is known about the effect of maternal supplementation in humans, as well as on its efficiency to increase levels of α-TOH in human milk, depending on the shape natural or synthetic. The study included 109 women, divided into three groups: control without supplementation (GC) (n=36), supplemented with natural capsule (GNAT) (n=40) and the synthetic capsule (GSINT) (n=33). Blood samples were collected for determination of maternal nutritional status, and colostrums at initial contact and after 24 hours post-supplementation. Analyses were performed by High Performance Liquid Chromatography. Values of α-TOH in serum below 499.6mg/dL were considered deficient. We used the Kruskal-Wallis test and Tukey test to confirm the increase of alpha-tocopherol in milk and efficiency of administered capsules. Daily consumption of α-TOH was based on daily intake of 500 mL of colostrum by the newborn and compared with the nutritional requirement for children from 0 to 6 months of age, 4 mg / day. The mothers had mean concentration of serum α-TOH in 1016 ± 52, 1236 ± 51 and 1083 ± 61 mg / dL, in CG, GNAT and GSINT respectively. There were no women with deficiiency. The GC did not change the concentrations of α-TOH in colostrum. While women supplemented with natural and synthetic forms increased concentrations of α-TOH colostrum in 57.6% and 39%, respectively. By comparing supplemented groups, it was observed a significant difference (p=0.04), the natural capsule more efficient than the synthetic, approximately 49.6%. Individually, 21.1% of the women provided below 4mg/day of α-TOH, after supplementation for this index declined4.1%. Thus, maternal supplementation postpartum raised the levels of alpha-tocopherol in colostrum, and increased efficiency was observed with the natural form

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Seaweeds are a major source of biologically active compounds . In the extracellular matrix of these organisms are sulfated polysaccharides that functions as structural components preventing it against dehydration. The fraction 0.9 (FucB) rich in sulfated fucans obtained from brown seaweed Dictyota menstrualis was chemical characterized and evaluated for pharmacological activity by testing anticoagulant activity, stimulatory action on the synthesis of an antithrombotic heparan sulfate, antioxidant activity and its effects in cell proliferation. The main components were FucB carbohydrates (49.80 ± 0.10 %) and sulfate (42.30 ± 0.015 %), with phenolic compounds ( 3.86 ± 0.016 %) and low protein contamination ( 0.58 ± 0.001 % ) . FucB showed polydisperse profile and analysis of signals in the infrared at 1262, 1074 and 930 cm -1 and 840 assigned to S = O bonds sulfate esters , CO bond presence of 3,6- anhydrogalactose , β -D- galactose non- sulfated sulfate and the axial position of fucose C4 , respectively. FucB exhibited moderate anticoagulant activity , the polysaccharides prolonged time (aPTT ) 200 ug ( > 90s ) partial thromboplastin FucB no effect on prothrombin time (PT), which corresponds to the extrinsic pathway of coagulation was observed. This stimulation promoted fraction of about 3.6 times the synthesis of heparan sulfate (HS) by endothelial cells of the rabbit aorta ( RAEC ) in culture compared with cells not treated with FucB . This has also been shown to compete for the binding site with heparin. The rich fraction sulfated fucans exhibited strong antioxidant activity assays on total antioxidant (109.7 and 89.5 % compared with BHT and ascorbic acid standards ) , reducing power ( 71 % compared to ascorbic acid ) and ferric chelation ( 71 , comparing with 5 % ascorbic acid). The fraction of algae showed cytostatic activity on the RAEC cells revealed that the increase of the synthesis of heparan sulfate is not related to proliferation. FucB showed antiproliferative action on cell lines modified as Hela and Hep G2 by MTT assay . These results suggest that FucB Dictyota menstrualis have anticoagulant , antithrombotic , antioxidant potential as well as a possible antitumor action, promoting the stimulation of the synthesis of antithrombotic HS by endothelial cells and is useful in the prevention of thrombosis, also due to its inhibitory action on species reactive oxygen ( ROS ) in some in vitro systems , being involved in promoting a hypercoagulable state

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Human mesenchymal stem cells (MSC) are powerful sources for cell therapy in regenerative medicine. The long time cultivation can result in replicative senescence or can be related to the emergence of chromosomal alterations responsible for the acquisition of tumorigenesis features in vitro. In this study, for the first time, the expression profile of MSC with a paracentric chromosomal inversion (MSC/inv) was compared to normal karyotype (MSC/n) in early and late passages. Furthermore, we compared the transcriptome of each MSC in early passages with late passages. MSC used in this study were obtained from the umbilical vein of three donors, two MSC/n and one MSC/inv. After their cryopreservation, they have been expanded in vitro until reached senescence. Total RNA was extracted using the RNeasy mini kit (Qiagen) and marked with the GeneChip ® 3 IVT Express Kit (Affymetrix Inc.). Subsequently, the fragmented aRNA was hybridized on the microarranjo Affymetrix Human Genome U133 Plus 2.0 arrays (Affymetrix Inc.). The statistical analysis of differential gene expression was performed between groups MSC by the Partek Genomic Suite software, version 6.4 (Partek Inc.). Was considered statistically significant differences in expression to p-value Bonferroni correction ˂.01. Only signals with fold change ˃ 3.0 were included in the list of differentially expressed. Differences in gene expression data obtained from microarrays were confirmed by Real Time RT-PCR. For the interpretation of biological expression data were used: IPA (Ingenuity Systems) for analysis enrichment functions, the STRING 9.0 for construction of network interactions; Cytoscape 2.8 to the network visualization and analysis bottlenecks with the aid of the GraphPad Prism 5.0 software. BiNGO Cytoscape pluggin was used to access overrepresentation of Gene Ontology categories in Biological Networks. The comparison between senescent and young at each group of MSC has shown that there is a difference in the expression parttern, being higher in the senescent MSC/inv group. The results also showed difference in expression profiles between the MSC/inv versus MSC/n, being greater when they are senescent. New networks were identified for genes related to the response of two of MSC over cultivation time. Were also identified genes that can coordinate functional categories over represented at networks, such as CXCL12, SFRP1, xvi EGF, SPP1, MMP1 e THBS1. The biological interpretation of these data suggests that the population of MSC/inv has different constitutional characteristics, related to their potential for differentiation, proliferation and response to stimuli, responsible for a distinct process of replicative senescence in MSC/inv compared to MSC/n. The genes identified in this study are candidates for biomarkers of cellular senescence in MSC, but their functional relevance in this process should be evaluated in additional in vitro and/or in vivo assays

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In this work, ceramic powders belonging to the system Nd2-xSrxNiO4 (x = 0, 0.4, 0.8, 1.2 and 1.6) were synthesized for their use as catalysts to syngas production partial. It was used a synthesis route, relatively new, which makes use of gelatin as organic precursor. The powders were analyzed at several temperatures in order to obtain the perovskite phase and characterized by several techniques such as thermal analysis, X-rays diffraction, Rietveld refinement method, specific surface area, scanning electron microscopy, energy dispersive spectroscopy of X-rays and temperature programmed reduction. The results obtained using these techniques confirmed the feasibility of the synthesis method employed to obtain nanosized particles. The powders were tested in differential catalytic conditions for dry reforming of methane (DRM) and partial oxidation of methane (POM), then, some systems were chosen for catalytic integrals test for (POM) indicating that the system Nd2-xSrxNiO4 for x = 0, 0.4 and 1.2 calcined at 900 °C exhibit catalytic activity on the investigated experimental conditions in this work without showing signs of deactivation

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Polymer matrix composites offer advantages for many applications due their combination of properties, which includes low density, high specific strength and modulus of elasticity and corrosion resistance. However, the application of non-destructive techniques using magnetic sensors for the evaluation these materials is not possible since the materials are non-magnetizable. Ferrites are materials with excellent magnetic properties, chemical stability and corrosion resistance. Due to these properties, these materials are promising for the development of polymer composites with magnetic properties. In this work, glass fiber / epoxy circular plates were produced with 10 wt% of cobalt or barium ferrite particles. The cobalt ferrite was synthesized by the Pechini method. The commercial barium ferrite was subjected to a milling process to study the effect of particle size on the magnetic properties of the material. The characterization of the ferrites was carried out by x-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM) and vibrating sample magnetometry (VSM). Circular notches of 1, 5 and 10 mm diameter were introduced in the composite plates using a drill bit for the non-destructive evaluation by the technique of magnetic flux leakage (MFL). The results indicated that the magnetic signals measured in plates with barium ferrite without milling and cobalt ferrite showed good correlation with the presence of notches. The milling process for 12 h and 20 h did not contribute to improve the identification of smaller size notches (1 mm). However, the smaller particle size produced smoother magnetic curves, with fewer discontinuities and improved signal-to-noise ratio. In summary, the results suggest that the proposed approach has great potential for the detection of damage in polymer composites structures

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Among the many types of noise observed in seismic land acquisition there is one produced by surface waves called Ground Roll that is a particular type of Rayleigh wave which characteristics are high amplitude, low frequency and low velocity (generating a cone with high dip). Ground roll contaminates the relevant signals and can mask the relevant information, carried by waves scattered in deeper regions of the geological layers. In this thesis, we will present a method that attenuates the ground roll. The technique consists in to decompose the seismogram in a basis of curvelet functions that are localized in time, in frequency, and also, incorporate an angular orientation. These characteristics allow to construct a curvelet filter that takes in consideration the localization of denoise in scales, times and angles in the seismogram. The method was tested with real data and the results were very good

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The seismic processing technique has the main objective to provide adequate picture of geological structures from subsurface of sedimentary basins. Among the key steps of this process is the enhancement of seismic reflections by filtering unwanted signals, called seismic noise, the improvement of signals of interest and the application of imaging procedures. The seismic noise may appear random or coherent. This dissertation will present a technique to attenuate coherent noise, such as ground roll and multiple reflections, based on Empirical Mode Decomposition method. This method will be applied to decompose the seismic trace into Intrinsic Mode Functions. These functions have the properties of being symmetric, with local mean equals zero and the same number of zero-crossing and extremes. The developed technique was tested on synthetic and real data, and the results were considered encouraging

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In the Hydrocarbon exploration activities, the great enigma is the location of the deposits. Great efforts are undertaken in an attempt to better identify them, locate them and at the same time, enhance cost-effectiveness relationship of extraction of oil. Seismic methods are the most widely used because they are indirect, i.e., probing the subsurface layers without invading them. Seismogram is the representation of the Earth s interior and its structures through a conveniently disposed arrangement of the data obtained by seismic reflection. A major problem in this representation is the intensity and variety of present noise in the seismogram, as the surface bearing noise that contaminates the relevant signals, and may mask the desired information, brought by waves scattered in deeper regions of the geological layers. It was developed a tool to suppress these noises based on wavelet transform 1D and 2D. The Java language program makes the separation of seismic images considering the directions (horizontal, vertical, mixed or local) and bands of wavelengths that form these images, using the Daubechies Wavelets, Auto-resolution and Tensor Product of wavelet bases. Besides, it was developed the option in a single image, using the tensor product of two-dimensional wavelets or one-wavelet tensor product by identities. In the latter case, we have the wavelet decomposition in a two dimensional signal in a single direction. This decomposition has allowed to lengthen a certain direction the two-dimensional Wavelets, correcting the effects of scales by applying Auto-resolutions. In other words, it has been improved the treatment of a seismic image using 1D wavelet and 2D wavelet at different stages of Auto-resolution. It was also implemented improvements in the display of images associated with breakdowns in each Auto-resolution, facilitating the choices of images with the signals of interest for image reconstruction without noise. The program was tested with real data and the results were good

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The imprecision of the frontier that separates those cognitive deficits inherent to the human physiological aging process from those which represent the early signs of nervous system degenerative pathologies ,very prevalent among the elderly, has brought attention to the need of studies aiming to establish clinical and/or laboratorial criteria to allow this differentiation. Elderly people living in poor and developing countries are frequently exposed to precarious socioeconomic conditions which facilitate the development of an array of pathologies which have metabolic and nutritional dysfunctions as the established or proposed etiological agents. The levels of certain micronutrients, such as the vitamins B12 and B9 (folic acid), and of some intermediary metabolites, such as homocysteine are being thought of as etiological factors and/or as biological markers of a group of alterations which affect the normal functioning of the nervous system with important reflexes upon cognitive performance. This study aims to investigate the influence of homocysteine, B12 vitamin and folic acid levels on the cognitive performance of the low income elderly population. This transversal study took place in Natal, Rio Grande do Norte State, Brazil, and involved 205 dwelling elderly people, users of the Programa de Saúde da Família, a public healthcare program, maintained by the city s health authorities. A multidimensional questionnaire was used to assess the socio-demographic aspects and the overall health and nutrition conditions. The cognitive performance was measured by the use of the Portuguese version of the Mini Mental State Exam (MMSE). The serum levels of homocysteine, B12 vitamin and folic acid were determined by chemiluminescence. The association between the socio-demographic and serum levels of Hcy, B12 vitamin and folic acid was determined by multiple linear regression. Serum levels higher than 13.5 μmol/l, indicative of hyperhomocysteinemia (HHcy), were found on 25.4% of the sample, being more prevalent in men (p<0.05). Deficitary levels of folic acid (<5ng/mol) and of B12 vitamin (<193 pg/ml) were found on 3.9% and 10.2% of the sample respectively. A negative correlation was found between cognitive performance with both age and HHcy and a positive correlation was found between cognitive performance and schooling. The isolated HHcy R2 values were an explanation to only 4% of the variance of the MMSE scores. However, when associated with schooling and age, this model explains about 25% of this association

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The general aim of the research was to comprehend the Social Representations constructed by the man in the face of his companion s risk pregnancy caused by hypertensive syndromes. The study is of exploratory and descriptive character in a qualitative approach developed at two public maternity hospitals, both located in Natal-RN, with 65 men whose wives had undergone high-risk pregnancy. The project was submitted to the Ethics on Research Committee of the Federal University of Rio Grande do Norte, Brazil (CEP-UFRN), with favorable report no. 81/07. For data collection, the following multimethods were employed: a word free association test; a projective test for registering mental images; and a semistructured interview schedule. The speech contents were analyzed in accordance with the Theory of Social Representations and complemented by the Central Nucleus Theory. The discussion of the results was grounded on literary findings of the companion s participation in pregnancy as well as in risk pregnancy associated with hypertensive syndromes. The data showed fear as representation s central nucleus, while recollections of that feeling referred to death of both companion and child in addition to fear of the unknown. The categories preoccupation and carefulness, other feelings, and clinical picture of the disease represented components of the peripheral nucleus. The results concerning mental images followed the same category criteria of the word free association test fear, other feelings, preoccupation, carefulness, and clinical picture of the disease. After being processed in accordance with the principles of content analysis, the statements originated three thematic unities: fear and insecurity in the presence of the companion s risk pregnancy; attitudes of carefulness to the risk pregnancy of the partner; and humanized assistance during the companion s risk pregnancy. Considering the results, the conclusion is that the partner s risk pregnancy caused by hypertensive syndromes represents, for the man, feelings of fear, preoccupation, insecurity, lack of acceptance and information, as well as attitudes of carefulness. The results reveal necessity of reorganizing the obstetric assistance with an eye to including the man as participant in the reproductive process. That demands extension of humanized carefulness to the companion with a view to make him an active coadjutor in the assistance of high-risk pregnant