63 resultados para Níveis diferenciados de listagem da BM

em Universidade Federal do Rio Grande do Norte(UFRN)


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The financial crisis that occurred between the years 2007 and 2008, known as the subprime crisis, has highlighted the governance of companies in Brazil and worldwide. To monitor the financial risk, quantitative tools of risk management were created in the 1990s, after several financial disasters. The market turmoil has also led companies to invest in the development and use of information, which are applied as tools to support process control and decision making. Numerous empirical studies on informational efficiency of the market have been made inside and outside Brazil, revealing whether the prices reflect the information available instantly. The creation of different levels of corporate governance on BOVESPA, in 2000, made the firms had greater impairment in relation to its shareholders with greater transparency in their information. The purpose of this study is to analyze how the subprime financial crisis has affected, between January 2007 and December 2009, the volatility of stock returns in the BM&BOVESPA of companies with greater liquidity at different levels of corporate governance. From studies of time series and through the studies of events, econometric tests were performed by the EVIEWS, and through the results obtained it became evident that the adoption of good practices of corporate governance affect the volatility of returns of companies

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The financial crisis that occurred between the years 2007 and 2008, known as the subprime crisis, has highlighted the governance of companies in Brazil and worldwide. To monitor the financial risk, quantitative tools of risk management were created in the 1990s, after several financial disasters. The market turmoil has also led companies to invest in the development and use of information, which are applied as tools to support process control and decision making. Numerous empirical studies on informational efficiency of the market have been made inside and outside Brazil, revealing whether the prices reflect the information available instantly. The creation of different levels of corporate governance on BOVESPA, in 2000, made the firms had greater impairment in relation to its shareholders with greater transparency in their information. The purpose of this study is to analyze how the subprime financial crisis has affected, between January 2007 and December 2009, the volatility of stock returns in the BM&BOVESPA of companies with greater liquidity at different levels of corporate governance. From studies of time series and through the studies of events, econometric tests were performed by the EVIEWS, and through the results obtained it became evident that the adoption of good practices of corporate governance affect the volatility of returns of companies

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Carciniculture in Brazil occupies world-wide prominence due to shrimp culture, and the state of Rio Grande do Norte has presented the best results in the culture of the Litopenaeus vannamei in the last decade. This species has been shown to adapt easily to different environments and is between the five most cultivated penaeids of the world. The ponds are usually constructed in areas close to water courses and estuaries. Stock density and substrate ponds can pollute environment, causing losses in the growth and survival of the shrimps, being considered stress factors. Shrimps in inadequate densities and substrates can result reduced productivity of the farm; and favor diseases. So, it is important to verify how these variables influence the development of the animals in the culture farms. Our objective was to study the influence of the type of substrate and the stock density on the behavior and haemocyte count of the L. vannamei. Individually marked juvenile shrimps were kept in aquaria with 30 L of seawater and continuous aeration, in 12L-12D photoperiod. They were observed through Ad libitum and focal sampling instantaneous methods during thirty days, five times per week, six times per day (8:00 to 18:00) in windows of 15 minutes every two hours. The marking of carapace permitted quantifying molting and the feeding was supplied three times a day. Two experiments were carried out: the first one tested animals in the three different substrates (fine sand, smaller rocks-SPP and biggest rocks-SGR) with 33 shrimp/m2. In the second one, the animals were tested in three stock densities (26, 52 and 66 shrimp/m2) in fine sand substrate. At the end of experiment, biometry (first and second ones) and haemocyte count (second one) were made. The behavior of the L. vannamei seems to have been influenced by substrate and stocking density. In low granulometry of the substrate; the exploratory behavior became more frequent and inactivity of the shrimps was reduced. Burrowing was registered in sand substrate, specially in the initial period of the day. Cleaning was gradually higher along the day, presenting the biggest levels as the dark phase approached. The ingestion of feeding was more frequent in low density, and the animals were bigger and heavier at the end of the experiment. In the fine sand condition, the animals presented better growth, probably associated with the burrowing. The molting was equivalent in all types of substrate, but it was more frequent in high densities. Mortality of the shrimps was more frequent in high densities, and cannibalism and diseases were also registered in that condition. The clinical signals were similar to the ones of infectious mionecrosis (IMNV), generally associated with environment and physical stress. The haemocyte count was low for the hematologic standards of the penaeid, which we attributed for greater dilution of haemolymph in the postmolting phase. Smaller shrimps presented lower levels of haemocytes in relation to the bigger animals, count was also low in 26 shrimp/m2 density. The study demonstrates that stocking density and the granulometry of the substrate can affect the welfare, the health and the behavior of the L. vannamei. The sand substrate and low stocking density can be important tools in the management systems of shrimp production

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O crescimento demográfico de idosos é um fenômeno mundial e exerce influência sobre o desenvolvimento e funcionamento das sociedades. Fatores sociais, econômicos, ambientais, biológicos e culturais influenciam o processo de envelhecimento, que pode vir acompanhado de contínua perda na capacidade de adaptação do indivíduo ao meio ambiente, de maior vulnerabilidade ao estresse, limitações funcionais e diminuição da qualidade de vida do indivíduo. Todavia, ao longo do curso da vida, o indivíduo vivencia múltiplas exposições adversas à saúde, e o declínio da mobilidade surge como um dos primeiros sinais do envelhecimento, repercutindo na saúde física e mental do indivíduo. Para contribuir com o conhecimento sobre os desfechos relacionados ao envelhecimento e mobilidade, o estudo IMIAS investiga idosos em quatro países com diferentes perfis epidemiológicos. O presente estudo abordou os possíveis fatores associados ao declínio físico em idosos de distintas sociedades, sobre a perspectiva epidemiológica do curso da vida e dos biomarcadores da inflamação e do estresse. Objetivos: 1) Analisar as relações entre as adversidades sociais e econômicas, vivenciadas durante a infância, a fase adulta e a velhice, com o baixo desempenho físico em populações idosas, de diferentes contextos sociais, econômicos e culturais. 2) Verificar a associação entre os níveis elevados da proteína c-reativa (PCR) com o desempenho físico em idosos de diferentes populações. 3) Avaliar se a desregulação nos níveis de cortisol diurno exerce influência sobre o desempenho físico em idosos com distintos perfis epidemiológicos. Métodos: Foram utilizados dados da linha de base do IMIAS – Estudo Internacional de Mobilidade no Envelhecimento, composto por 1.995 indivíduos entre 65 e 74 anos de idade, residentes em comunidades de quatro países (Albânia, Brasil, Canadá, Colômbia). O desempenho físico foi avaliado através do Short Physical Performance Battery (SPPB) e da força de preensão manual. As adversidades durante o curso da vida foram estimadas a partir de eventos e exposições sociais, econômicas e culturais ocorridas durante a infância, fase adulta e velhice. Para avaliar o percurso biológico e suas associações com a mobilidade, a proteína c-reativa e o cortisol foram considerados como biomarcadores da inflamação e do estresse, respectivamente. No sentido de responder as questões de investigações, foram conduzidas análises de estatística descritiva, bivariada e multivariada, mediante técnicas de distribuição de frequências, teste qui-quadrado, odds ratio e regressões logística, linear e multinível. Resultados: O desempenho físico foi menor nos participantes que vivem na Colômbia, Brasil e Albânia do que nos que vivem no Canadá, mesmo quando ajustados por idade, sexo e adversidades durante o curso da vida. O baixo nível de desempenho físico (SPPB < 8) foi associado a ter sofrido adversidade social e econômica na infância, ter tido ocupação semiqualificada na fase adulta, morar sozinho e possuir renda insuficiente na velhice. A PCR esteve associada com a baixa força de preensão manual e com o SPPB<8. Entretanto, a associação entre a PCR e a força de preensão manual não se manteve quando ajustada por fatores socioeconômicos e hábitos de saúde. As associações negativas entre SPPB e PCR permaneceram significativas mesmo após ajustes por idade, sexo, escolaridade, local de pesquisa e condições de saúde. O baixo desempenho físico (SPPB ≤ 8) foi associado com uma significativa diminuição nos níveis de cortisol ao acordar, em comparação com os níveis de cortisol de idosos com bom desempenho físico (SPPB > 8), mesmo após modelos controlados por local de estudo, sexo, depressão, hábitos de saúde, uso de psicotrópicos e índice de massa corporal. Conclusões: Os resultados evidenciaram associação entre a inflamação, o estresse e as desigualdades sociais e econômicas na infância, sobre o desempenho físico de idosos com diferenciados perfis epidemiológicos. Enfatizamos que a promoção do envelhecimento saudável requer considerar políticas e práticas que favoreçam o bem-estar econômico e social para crianças, adultos e idosos.

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This study aims to investigate the influence of the asset class and the breakdown of tangibility as determinant factors of the capital structure of companies listed on the BM & FBOVESPA in the period of 2008-2012. Two current assets classes were composed and once they were grouped by liquidity, they were also analyzed by the financial institutions for credit granting: current resources (Cash, Bank and Financial Applications) and operations with duplicates (Stocks and Receivables). The breakdown of the tangible assets was made based on its main components provided as warrantees for loans like Machinery & Equipment and Land & Buildings. For an analysis extension, three metrics for leverage (accounting, financial and market) were applied and the sample was divided into economic sectors, adopted by BM&FBOVESPA. The data model in dynamic panel estimated by a systemic GMM of two levels was used in this study due its strength to problems of endogenous relationship as well as the omitted variables bias. The found results suggest that current resources are determinants of the capital structure possibly because they re characterized as proxies for financial solvency, being its relationship with debt positive. The sectorial analysis confirmed the results for current resources. The tangibility of assets has inverse proportional relationship with the leverage. As it is disintegrated in its main components, the significant and negative influence of machinery & equipment was more marked in the Industrial Goods sector. This result shows that, on average, the most specific assets from operating activities of a company compete for a less use of third party resources. As complementary results, it was observed that the leverage has persistence, which is linked with the static trade-off theory. Specifically for financial leverage, it was observed that the persistence is relevant when it is controlled for the lagged current assets classes variables. The proxy variable for growth opportunities, measured by the Market -to -Book, has the sign of its contradictory coefficient. The company size has a positive relationship with debt, in favor of static trade-off theory. Profitability is the most consistent variable in all the performed estimations, showing strong negative and significant relationship with leverage, as the pecking order theory predicts

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The dissertation intends to develop an investigation on the artistic existence in human beings with different bodies in society at different historical moments. In this regard and based on this scenario, the study develops a description of the stigmas production and how they are established, spread and interfere with the sociability among human beings regarded as normal and those with different bodies. Regarding the scenic arts, the text describes about the participation of artists with different bodies in the scene, specifically the freak show and postdramatic theater. The text also investigates aspects of the biography and the work of mexican artist Frida Kahlo, which underpin methodological proceedings and produce contribution to the creative process of performance Kahlo em mim Eu e(m) Kahlo , which is to investigate the practice of the scene in this dissertation

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The caprine milk is a product of high biological value and high digestibility. Due to these characteristics it is quite used by newly born children that are not breastfed or that are intolerant to the bovine milk. The vitamin deficiency is a public health problem in underdeveloped areas as the Northeast of Brazil and where areas the caprine ones adapt very well. The present study was led to analyze the influence of the feeding in the vitamin levels in the caprine milk. The animals used were the races Saanen and Murciana, divided in three groups. The first group with 38 animals of race Saanen and the second with 30 animals of race Murciana were, fed with concentrated and voluminous. A third group with 20 animals of the race Saanen was fed exclusively with voluminous. The four group was added with 10. 000 UI of retinol palmitato, administered directly, like capsule, in the mouth of animal. Parallel it was verified the level of retinol of milk in the beginning and final of the sucked, in the goats of the second group (race Murciana n =30). The retinol of caprine milk was determined through the system of liquid cromatografia of high efficiency (HPLC). The retinol levels in the studied groups were respectively: first (38. 5 ± 12. 7 μg/100ml), second (40. 5 ± 9. 7 μg/100ml); third, with 20 animals of race Saanen fed exclusively with voluminous (23. 1 ± 6. 7 μg/100ml) and in the group a, suplementation with 10. 000 UI of retinol palmitato (43,7 ± 18,8 μg/100ml) before, and (61,9 ± 26,9 μg/100ml) after the supplementation. It was not found significant difference between the averages from animals of the first and second group, that were fed with the same concentrate diet and voluminous, showing that the retinol levels in the milk of these two races are equivalent. Already in the animals of the first and third group that they were fed with different diets, in those which diet was just voluminous, a drastic reduction was verified in the retinol levels. In relation to the retinol of the milk in different moments from the same sucked, it was observed in the beginning of the breast-feeding (22. 6 ± 9. 8 μg/100ml) and at the end of the sucked (49. 6 ± 14. 7μg/100ml), being the difference between the averages, statistically significant (p < 0,0001). Already in the animals that were supplemented, a significant increase was observed in the retinol concentration, being obtained a medium response of 41,85%

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The vitamins A and E are recognizably important in the initial stages of life and the newborn depends on nutritional adequacy of breast milk to meet their needs. These vitamins share routes of transport to the tissues and antagonistic effects have been observed in animals after supplementation with vitamin A. This study aimed to verify the effect of maternal supplementation with vitamin A megadose (200,000 UI) in the immediate post-partum on the concentration of alpha-tocopherol in colostrum. Healthy parturient women attended at a public maternity natalensis were recruited for the study and divided into two groups: control (n = 37) and supplemented (n = 36). Blood samples of colostrum and milk were collected until 12 hours after delivery. The women of the supplemented group was administered a retynil palmitate capsule and 24 hours after the first collection was obtained the 2nd sample of colostrum in two groups for analysis of retinol and alpha-tocopherol in milk. The mean retinol concentration of 50,7 ± 14,4 μg/dL (Mean ± standard deviation) and alpha-tocopherol of 1217.4 ± 959 mg/dL in the serum indicate the nutritional status biochemical appropriate. Supplementation with retynil palmitate resulted in increase not only retinol levels in the colostrum of the supplemented group (p = 0.002), but also the concentration of alpha-tocopherol (p = 0.04), changing from 1456.6 ± 1095.8 mg/dL to 1804.3 ± 1432.0 mg/dL (milk 0 and 24 respectively) compared to values in the control group, 984.6 ± 750.0 mg/dL and 1175.0 ± 730.8 mg/dL. The women had different responses to supplementation, influenced by baseline levels of retinol in colostrum. Those with previous by low levels of retinol in colostrum (<60 mg/dL) had increased the concentration of alpha-tocopherol in milk, whereas those with adequate levels (> 60 mg/dL), showed a reduction after supplementation. Supplementation with retinol palmitate is an important intervention in situations of high risk for vitamin A deficiency, when considering the need to maternal supplementation, since the excess vitamin can offer unfavorable interactions between nutrients essential for the mother-child group

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Mothers with good vitamin A nutritional status during gestation and lactation are better able to nourish and protect their infant with maternal milk. Our hypothesis is that women with more serum retinol have more retinol and secretory immunoglobulin A in colostrum. 190 healthy puerperal women from a Brazilian public maternity were recruited and divided according to the cutoff point for serum retinol (30 μg/dL). A number of the women was supplemented with 200000 UI (60 mg) of retinyl palmitate in the immediate postpartum. Serum and colostrum were collected on the 1st day postpartum and colostrum again on the following day. Retinol (serum and colostrum) was analyzed by HPLC and SIgA (colostrum) by turbidimetry. The mothers presented with adequate biochemical indicators of nutritional status, according to serum retinol (44.6 μg/dL). There were significant differences (p= 0.0017 and p= 0.043, respectively) in retinol and SIgA levels in the colostrum of mothers with serum retinol > 30 μg/dL and < 30 μg/dL. The concentration of SIgA in the colostrum of non-supplemented mothers on the 1st day postpartum was 822.6 mg/dL, decreasing after 24 hours to 343.7 mg/dL. Supplemented mothers showed levels of SIgA in colostrum of 498.9 mg/dL on the 2nd day postpartum (p= 0.00006). The colostrum of women with good vitamin A nutritional status had more retinol and SIgA. Additionally, maternal supplementation increases the levels of SIgA in colostrum. The higher levels of SIgA on the 1st day postpartum showed the importance of early breastfeeding, given that it provides considerable immunological benefits to newborn infants

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Vitamins A and E are essential nutrients in many biological processes, so that their adequate supply to the neonate is crucial. However, the bioavailability of vitamins may be limited by factors such as maternal nutritional status and the interaction between nutrients. This study aimed to investigate the effect of biochemical nutritional status of retinol and alpha-tocopherol levels in serum and colostrum. The study included 103 healthy puerperal women treated at the reference state maternity hospital (Natal-RN). Colostrum and serum samples were collected fasting in the immediate postpartum period and the analysis of retinol and alpha-tocopherol were determined by high-performance liquid chromatography. Specific cutoff points were adopted to characterize the biochemical status of vitamins A and E. For the total group of lactanting women the average concentration of retinol in serum (1.49 ± 0.4 μmol/L-1) and colostrum (2.18 ± 0.8 μmol/L-1), as well as alpha-tocopherol in serum (26.4 ± 8.0 μmol/L-1) and colostrum (26.1 ± 12.8 μmol/L-1), indicated adequate biochemical state. However, when evaluating the individual, was found a high prevalence of deficient serum (15%) and colostrum retinol (50%), and also alphatocopherol in serum (16%) and colostrum (61%). In women with serum retinol ≥ 1.05 μmol/L-1, found an inverse correlation between serum retinol and alpha-tocopherol in colostrum (p = 0.008, r = -0.28). This association was not observed in women with serum retinol <1.05 μmol/L-1. This situation demonstrates for the first time in humans that high physiological levels of serum retinol, without supplementation, can negatively influence the transfer of alpha-tocopherol in breast milk. Although the diagnosis of satisfactory nutritional status lactanting women showed high risk of subclinical deficiency of vitamins A and E from measurements made in the colostrum

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Dopamine (DA) is known to regulate both sleep and memory formations, while sleep plays a critical role in the consolidation of different types of memories. We believe that pharmacological manipulation of dopaminergic pathways might disrupt the sleep-wake cycle, leading to mnemonic deficits, which can be observed in both behavioral and molecular levels. Therefore, here we investigated how systemic injections of haloperidol (0.3 mg/kg), immediately after training in dark and light periods, affects learning assessed in the novel object preference test (NOPT) in mice. We also investigated the hippocampal levels of the plasticity-related proteins Zif-268, brain-derived neurotrophic factor (BDNF) and phosphorylated Ca2+/calmodulin-dependent protein kinases II (CaMKII-P) in non-exposed (naïve), vehicle-injected controls and haloperidol-treated mice at 3, 6 and 12 hours after training in the light period. Haloperidol administration during the light period led to a subsequent impairment in the NOPT. In contrast, preference was not observed during the dark period neither in mice injected with haloperidol, nor in vehicle-injected animals. A partial increase of CaMKII-P in the hippocampal field CA3 of vehicle-injected mice was detected at 3h. Haloperidol-treated mice showed a significant decrease in the dentate gyrus of CaMKII-P levels at 3, 6 and 12h; of Zif-268 levels at 6h, and of BDNF levels at 12h after training. Since the mnemonic effects of haloperidol were only observed in the light period when animals tend to sleep, we suggest that these effects are related to REM sleep disruption after haloperidol injection

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Vitamin A deficiency is a serious public health problem in developing countries, and it causes death and blindness among children in the developing countries. The fortification of food could be an important source of vitamins to control deficiency. 60 Coturnix coturnix japonica quails were used in a randomized design with duration of seven weeks. The birds were assigned into five treatments with four repetitions. The objective was to evaluate the influence of the supplementation with different levels of retinyl palmitate (2,000 IU, 4,000 IU, 8,000IU and 16,000 IU) in quails under the levels of retinyl in egg yolks. The method used to dose retinyl in yolks of quail eggs was High Performance Liquid Chromatography and the enzymatic method to quantify the cholesterol concentration. The weight and production of eggs was significantly modified by the supplementation with retinyl in the birds. The results showed a gradual increase in the incorporation of retinyl in the egg yolk as a response to the supplementation, reaching values 384% higher than the control values. By the end of the supplementations a significant reduction in the concentrations of retinyl in the eggs yolk was observed. The most lasting supplementations were with 8,000 IU and 16,000 IU which lasted for three weeks. The cholesterol content in eggs was not significantly modified. The consumption of one egg enriched with 16000UI of retinol palmitate in the present study, by day, would probably reach 10 and 7,3% of the daily recommendations of this micronutrient for children of 1 to 3 years of age, and for 4 to 8 years, respectively. The nutritional value of eggs, related to the vitamin A, can be improved by supplementation of quails

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The tendency towards reduction of serum retinol levels, an existing placental barrier and the increase of retinol demand, are factors that place puerperal and lactating women at risk for Vitamin A deficiency. This micronutrient is an essential component of vital processes such as differentiation, cellular proliferation, and apoptosis. The objective of this study is to evaluate the effect of palmitate retinol supplementation (100.000UI) upon the milk retinollevels in puerperal women at the Januário Cicco University Maternity Hospital. This intervention has been adopted by the Ministry of Health since 2002. The longitudinal experiment was conducted with 106 puerperal women (68 comprised the supplemented group and 38 the control group). The High Performance Liquid Chromatography (HPLC) method was used to dose the retinol of the milk and serum samples, and the creamtocrit method to determine the milk fat levels. The retinol means for the colostrums were 99.0 ± 64.4 ug/dL and 160.1 ± 94,4 ug/dl 6 hours afier supplementation; 68.9 ± 33.5 ug/dL for the transitional milk, and 30.6 ± 15.2 ug/dL for the mature milk of the supplemented group. Ali the difterences between means were statistically significant. The difterence between retinol means in the control group were also significant, with these being greater in the colostrum, 88.6 ± 62.1 ug/dL with 61.9 ± 30.1 ug/dl in the transition milk and 32.9 ±32.9 ± 17.6 ug/dL in the mature milk. No significant difference was observed in the retinol means of the three types ot milk in the supplemented group when compared to their respective means in the control group. The prevalence in serum (35.1 % and 81.1 % for the cutting point 20 ug/dL, respectively) and in milk (51.4%) revealed vitamin A deficiency as a public health problem. COlostrum, transition, and mature milk tats varied similarly in the supplemented group (1,92 ± 0,96; 3,25 ± 1,27 and 3,31 ± 1,36 grams) and in the control group (1,87 ± 1,14; 3,25 ± 1,31 and 3,36 ± 1,67 grams), with an observed difference between the colostrum/transition milk and the colostrum/mature milk fats. No difference was observed between the groups. The study showed that the 200.000UI supplementation was not sufficient to increase the milk retinol to the desired levels nor to meet the demands of the mothers with deprived hepatic reserves. It is suggested that another similar dose be offered within 30 days or less, and within 2 months post-partum, while continual/y monitoring for possible pregnancy

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Despite advances in antibiotic therapy, bacterial meningitis (BM) remains with high mortality and morbidity rates in worldwide. One important mechanism associated to sequels during disease is the intense inflammatory response which promotes an oxidative burst and release of reactive oxygen species, consequently leading to cell death. Activation of DNA repair enzymes during oxidative stress has been demonstrated in several neurological disorders. APE1/Ref-1 is a multifunctional protein involved in DNA repair and plays a redox function on transcription factors such as NFkB and AP-1.The aim of this study was assess the role of APE1/Ref-1 on inflammatory response and the possibility of its modulation to reduce the sequels of the disease. Firstly it was performed an assay to measure cytokine in cerebrospinal fluid of patients with BM due to Streptococcus pneumoniae and Neisseriae meningitides. Further, a cellular model of inflammation was used to observe the effect of the inhibition of the endonuclease and redox activity of APE1/Ref-1 on cytokine levels. Additionally, APE1/Ref-1 expression in cortex and hippocampus of rat with MB after vitamin B6 treatment was evaluated. Altogether, results showed a similar profile of cytokines in the cerebrospinal fluid of patients from both pathogens, although IFNy showed higher expression in patients with BM caused by S. pneumoniae. On the other hand, inhibitors of APE1/Ref-1 reduced cytokine levels, mainly TNF-α. Reduction of oxidative stress markers was also observed after introduction of inhibitors in the LPS-stimulated cell. In the animal model, BM increased the expression of the protein APE1/Ref-1, while vitamin B6 promoted reduction. Thereby, this data rise important factors to be considered in pathogenesis of BM, e.g., IFNy can be used as prognostic factor during corticosteroid therapy, APE1/Ref-1 can be an important target to modulate the level of inflammation and VIII oxidative stress, and vitamin B6 seems modulates several proteins related to cell death. So, this study highlights a new understanding on the role of APE1/Ref-1 on the inflammation and the oxidative stress during inflammation condition

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In vitro and in animal models, APE1, OGG1, and PARP-1 have been proposed as being involved with inflammatory response. In this work, we have investigated if the SNPs APE1 Asn148Glu, OGG1 Ser326Cys, and PARP-1 Val762Ala are associated to meningitis and also developed a system to enable the functional analysis of polymorphic proteins. Patients with bacterial meningitis (BM), aseptic meningitis (AM) and controls (non-infected) genotypes were investigated by PIRA-PCR or PCR-RFLP. DNA damages were detected in genomic DNA by Fpg treatment. IgG and IgA were measured from plasma and the cytokines and chemokines were measured from cerebrospinal fluid samples using Bio-Plex assays. The levels of NF-κB and c-Jun were measured in CSF by dot blot assays. A significant (P<0.05) increase in the frequency of APE1 148Glu allele in BM and AM patients was observed. A significant increase in the genotypes Asn/Asn in control group and Asn/Glu in BM group was also found. For the SNP OGG1 Ser326Cys, the genotype Cys/Cys was more frequent (P<0.05) in BM group. The frequency of PARP-1 Val/Val genotype was higher in control group (P<0.05). The occurrence of combined SNPs increased significantly in BM patients, indicating that these SNPs may be associated to the disease. Increasing in sensitive sites to Fpg was observed in carriers of APE1 148Glu allele or OGG1 326Cys allele, suggesting that SNPs affect DNA repair activity. Alterations in IgG production were observed in the presence of SNPs APE1Asn148Glu, OGG1Ser326Cys or PARP-1Val762Ala. Reductions in the levels ofIL-6, IL-1Ra, MCP-1/CCL2and IL-8/CXCL8 were observed in the presence of APE1148Glu allele in BM patients, however no differences were observed in the levels of NF-κB and c-Jun considering genotypes and analyzed groups. Using APE1 as model, a system to enable the analysis of cellular effects and functional characterization of polymorphic proteins was developed using strategies of cloning APE1 cDNA in pIRES2-EGFP vector, cellular transfection of the construction obtained, siRNA for endogenous APE1 and cellular cultures genotyping. In conclusion, we obtained evidences of an effect of SNPs in DNA repair genes on the regulation of immune response. This is a pioneering work in the field that shows association of BER variant enzymes with an infectious disease in human patients, suggesting that the SNPs analyzed may affect immune response and damage by oxidative stress level during brain infection. Considering these data, new approaches of functional characterization must be developed to better analysis and interactions of polymorphic proteins in response to this context