979 resultados para Glutationa reduzida
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The use of raw materials from renewable sources for production of materials has been the subject of several studies and researches, because of its potential to substitute petrochemical-based materials. The addition of natural fibers to polymers represents an alternative in the partial or total replacement of glass fibers in composites. In this work, carnauba leaf fibers were used in the production of biodegradable composites with polyhydroxybutyrate (PHB) matrix. To improve the interfacial properties fiber / matrix were studied four chemical treatments to the fibers..The effect of the different chemical treatments on the morphological, physical, chemical and mechanical properties of the fibers and composites were investigated by scanning electron microscopy (SEM), infrared spectroscopy, X-ray diffraction, tensile and flexural tests, dynamic mechanical analysis (DMA), thermogravimetry (TGA) and diferential scanning calorimetry (DSC). The results of tensile tests indicated an increase in tensile strength of the composites after the chemical treatment of the fibers, with best results for the hydrogen peroxide treated fibers, even though the tensile strength of fibers was slightly reduced. This suggests a better interaction fiber/matrix which was also observed by SEM fractographs. The glass transition temperature (Tg) was reduced for all composites compared to the pure polymer which can be attributed to the absorption of solvents, moisture and other low molecular weight molecules by the fibers
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The oil production in mature areas can be improved by advanced recovery techniques. In special, steam injection reduces the viscosity of heavy oils, thus improving its flow to surrounding wells. On the other hand, the usually high temperatures and pressures involved in the process may lead to cement cracking, negatively affecting both the mechanical stability and zonal isolation provided by the cement sheath of the well. The addition of plastic materials to the cement is an alternative to prevent this scenario. Composite slurries consisting of Portland cement and a natural biopolymer were studied. Samples containing different contents of biopolymer dispersed in a Portland cement matrix were prepared and evaluated by mechanical and rheological tests in order to assess their behavior according to API (American Petroleum Institute) guidelines. FEM was also applied to map the stress distribution encountered by the cement at bottom bole. The slurries were prepared according to a factorial experiment plan by varying three parameters, i.e., cement age, contents of biopolymer and water-to-cement ratio. The results revealed that the addition of the biopolymer reduced the volume of free water and the setting time of the slurry. In addition, tensile strength, compressive strength and toughness improved by 30% comparing hardened composites to plain Portland slurries. FEM results suggested that the stresses developed at bottomhole may be 10 to 100 times higher than the strength of the cement as evaluated in the lab by unconfined mechanical testing. An alternative approach is proposed to adapt the testing methodology used to evaluate the mechanical behavior of oilwell cement slurries by simulating the confined conditions encountered at bottornhole
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The research and development of wind turbine blades are essential to keep pace with worldwide growth in the renewable energy sector. Although currently blades are typically produced using glass fiber reinforced composite materials, the tendency for larger size blades, particularly for offshore applications, has increased the interest on carbon fiber reinforced composites because of the potential for increased stiffness and weight reduction. In this study a model of blade designed for large generators (5 MW) was studied on a small scale. A numerical simulation was performed to determine the aerodynamic loading using a Computational Fluid Dynamics (CFD) software. Two blades were then designed and manufactured using epoxy matrix composites: one reinforced with glass fibers and the other with carbon fibers. For the structural calculations, maximum stress failure criterion was adopted. The blades were manufactured by Vacuum Assisted Resin Transfer Molding (VARTM), typical for this type of component. A weight comparison of the two blades was performed and the weight of the carbon fiber blade was approximately 45% of the weight of the fiberglass reinforced blade. Static bending tests were carried out on the blades for various percentages of the design load and deflections measurements were compared with the values obtained from finite element simulations. A good agreement was observed between the measured and calculated deflections. In summary, the results of this study confirm that the low density combined with high mechanical properties of carbon fibers are particularly attractive for the production of large size wind turbine blades
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The extent of the Brazilian Atlantic rainforest, a global biodiversity hotspot, has been reduced to less than 7% of its original range. Yet, it contains one of the richest butterfly fauna in the world. Butterflies are commonly used as environmental indicators, mostly because of their strict association with host plants, microclimate and resource availability. This research describes diversity, composition and species richness of frugivorous butterflies in a forest fragment in the Brazilian Northeast. It compares communities in different physiognomies and seasons. The climate in the study area is classified as tropical rainy, with two well defined seasons. Butterfly captures were made with 60 Van Someren-Rydon traps, randomly located within six different habitat units (10 traps per unit) that varied from very open (e.g. coconut plantation) to forest interior. Sampling was made between January and December 2008, for five days each month. I captured 12090 individuals from 32 species. The most abundant species were Taygetis laches, Opsiphanes invirae and Hamadryas februa, which accounted for 70% of all captures. Similarity analysis identified two main groups, one of species associated with open or disturbed areas and a second by species associated with shaded areas. There was a strong seasonal component in species composition, with less species and lower abundance in the dry season and more species and higher abundance in the rainy season. K-means analysis indicates that choice of habitat units overestimated faunal perceptions, suggesting less distinct units. The species Taygetis virgilia, Hamadryas chloe, Callicore pygas e Morpho achilles were associated with less disturbed habitats, while Yphthimoides sp, Historis odius, H. acheronta, Hamadryas feronia e Siderone marthesia likey indicate open or disturbed habitats. This research brings important information for conservation of frugivorous butterflies, and will serve as baseline for future projects in environmental monitoring
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O objetivo desse estudo foi determinar a tolerância de banana (Musa spp.) 'Prata-Anã' (AAB) e do fungo Colletotrichum musae à termoterapia no controle de podridões em pós-colheita. Experimentos in vivo e in vitro foram instalados em delineamento inteiramente casualizado, seguindo um esquema fatorial 4x5 (temperatura x tempo). Os tratamentos consistiram na imersão dos frutos (buquês) e do fungo (esporos e micélio) em água aquecida a 47, 50, 53 e 56 ºC, durante 0, 3, 6, 9 e 12 min. A exposição dos frutos a 56 ºC durante 9 min causou escurecimento da casca nas extremidades dos frutos, porém, as características físicas e químicas dos frutos não foram alteradas pelos tratamentos. Frutos inoculados e tratados a 56 ºC durante 6 min não apresentaram podridões nem escurecimento da casca, enquanto aqueles não tratados apresentaram 64% da área lesionada / fruto. A partir das combinações 53 ºC / 9 mi. e 56 ºC / 3 min a germinação de esporos foi reduzida para 4% e 0%, respectivamente. A combinação 56 ºC / 12 min reduziu, mas não paralisou o crescimento micelial. O tratamento 56 ºC / 6 min retardou mas não paralisou o crescimento micelial in vitro, porém foi efetivo no controle completo das podridões in vivo. Esse tratamento evitou a manifestação de podridões no inverno (maio), mas não no verão (novembro), mostrando-se influenciado pelas condições climáticas próximas à colheita dos cachos. A termoterapia pode ser recomendada para controle de podridão em pós-colheita de banana devendo ser ajustada para diferentes estações do ano.
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Body image is the figure of our bodies built in our minds and the degree of dissatisfaction is often associated with risk factors identified by anthropometric measures. The purpose of this descriptive study was to evaluate the risk factors associated to morphological and functional variables associate to the perception of auto-image in middle-aged walkers of the south zone of the city of Natal. A hundred and thirty volunteers had been evaluated in four groups in function of the gender and age group. As measurement evaluations were used an auto-image perception questionnaire proposed by Stunkart of nine silhouettes numbered for both gender was applied; a weighing machine equipped with stadiometer for the body mass (kg) and stature (m) and the body mass index (kg/m2) that was calculated with base in measures of the body weight and stature and classified according to norms of the National Institute of Health (2000) as well as the systolic and diastolic blood pressure by a electronic digital device (DIGITRONIC). A metal anthropometric tape was used for the waist to hip ratio (WHR). It was used Analyses of variance (ANOVA) one-way, post hoc of Tukey and correlation of Spearman for the nonparametric data adopting the level of ρ≤ 0,05 for rejection of the null hypothesis. The body mass index indicated high factors of risk in the consisting groups. In all the groups were registered the desire to reduce their silhouettes. The body weight shows reduced when compared with the younger group in the male group of superior age group, while in the female group the inverse one occurs. The autoimage perception is associated with the classification of the waist to hip ratio in the female gender in the age group of the 50 to the 59 years and in the classification of the body mass index of all constituted groups. Significant associations had not been found for classification of the systolic and diastolic blood pressure in relation to the auto-image 41 perception. This thesis presents relation of interdisciplinarity and its contents have application in the fields of Physical Education, Medicine, Physiotherapy and Nursing
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A população de cervo-do-pantanal (Blastocerus dichotomus) está drasticamente reduzida no Brasil. O nosso objetivo foi o de estimar a abundância do cervo-do-pantanal na bacia do Rio Paraná e discutir a metodologia aplicada. Os resultados darão suporte para uma análise do impacto do enchimento da represa de Porto Primavera sobre essa população. Sessenta e nove animais foram registrados através de sobrevôo utilizando-se a metodologia de transecção linear com amostragem das distâncias. Os dados não corrigidos resultaram em uma densidade estimada de 0,0035ind/ha e uma população de 636 indivíduos. A correção de g para os animais que não foram vistos apresentou uma densidade de 0,0049 ind/ha e uma abundância de 896 (CV=0,27) indivíduos. A metodologia foi aplicada com sucesso na estimativa de cervo-do-pantanal. Esse resultado é importante para avaliarmos a população do cervo-do-pantanal na área e para futuramente analisarmos o impacto do enchimento da represa.
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Farming of marine shrimp is growing worldwide and the Litopenaeus vannamei (L. vannamei) shrimp is the species most widely cultivated. Shrimp is an attractive food for its nutritional value and sensory aspects, being essential the maintenance of this attributes throughout storage, which takes place largely under freezing. The aim of this research was to evaluate quality characteristics of Litopenaeus vannamei shrimp, during freezing storage and to verify the effect of rosemary (Rosmarinus officinalis) adding. Considering the reutilization of processing shrimp wastes, total carotenoids analysis were conducted in waste of Litopenaeus vannamei shrimp and in the flour obtained after dryer. Monthly physicochemical and sensorial analysis were carried out on shrimp stored at 28,3 ± 3,8ºC for 180 days. Samples were placed in polyethylene bags and were categorized as whole shrimp (WS), peeled shrimp (PS), and PS with 0,5% dehydrated rosemary (RS). TBARS, pH, total carotenoid and sensorial Quantitative Descriptive Analysis (QDA) were carried out. Carotenoid total analysis was conducted in fresh wastes and processed flour (0 day) and after 60, 120 and 180 days of frozen storage. After 180 days, RS had lower pH (p = 0.001) and TBARS (p = 0.001) values and higher carotenoids (p = 0.003), while WS showed higher carotenoid losses. Sensory analysis showed that WS were firmer although rancid taste and smell were perceived with greater intensity (p = 0.001). Rancid taste was detected in RS only at 120 days at significantly lower intensity (p = 0.001) than WS and PS. Fresh wastes had 42.74μg/g of total carotenoids and processed flour 98.51μg/g. After 180 days of frozen storage, total carotenoids were significantly lower than 0 day (p<0,05). The addition of rosemary can improve sensory quality of frozen shrimp and reduce nutritional losses during storage. Shrimp wastes and flour of L. vannamei shrimp showed considerable astaxanthin content however, during storage it was observed losses in this pigment
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Compounded medicines have been reported by the ANVISA due to decreased of the therapeutic response or toxicity of these formulations. The aim of this work was to investigate the physicochemical quality control among naproxen sodium oral suspensions 25 mg/mL obtained from six compounding pharmacies (A, B, C, D, E and F) and the manufactured suspension (R). In the quality control test, the tests of pH, content, homogeneity, volume and physical and organoleptic characteristics were performed according to the Brazilian Pharmacopoeia. The analytical method for determination of naproxen in suspensions was validate. This method showed excellent precision, accuracy, linearity and specificity. In the content test the suspensions B, C and E showed lower value and the F suspension showed a high value of the content. The products C and E were disapproved in the description of the physical and organoleptic characteristics test. In the pH test, three suspensions were outside specifications (C, E and F). Only the products R, A and D showed satisfactory results in these tests and therefore they were approved for relative bioavailability test. The R, A and D suspensions were orally administered to Wistar rats and the blood samples were taken at time intervals of 10, 20, 40, 60 min, 3, 4, 6, 24 and 48 h. The plasma samples were immediately stored at 80 ºC until analysis of HPLC. The bioanalytical method validation showed specificity, linearity (R2 0.9987), precision, accuracy, good recovery and stability. The chromatographic conditions were: flow rate of 1.2 mL.min-1 with a mobile phase of acetonitrile : sodium phosphate buffer pH 4.0 (50:50, v/v) at 280 nm, using a C18 column. The confidence interval of 90% for the Cmax and AUCt ratio was within the range of 80 - 125% proposed by the FDA. Only one suspension, obtained from the compounding pharmacy D, was considered bioequivalent to the rate of absorption under the conditions proposed by this study. Thus, the results indicate the need for strict supervision from the relevant authorities to ensure the patient safety and the quality of compounded drugs by pharmacies
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Os feijões estão entre os alimentos mais antigos, fazendo parte da alimentação diária da população brasileira. Objetivou-se com este trabalho determinar o período de convivência anterior à interferência das plantas daninhas (PAI) na cultura do feijoeiro em diferentes espaçamentos e densidades de plantas. Os tratamentos foram constituídos de períodos de convivência entre a cultura e as plantas daninhas, sendo zero a dez, zero a 20, zero a 30, zero a 40, zero a 50, zero a 60, zero a 70 e zero a 80 dias e mais uma testemunha sem convívio com as plantas daninhas. Além dos períodos de convivência, realizaram-se ainda estudos com espaçamentos entre linhas de 0,45 e 0,60 m e mais duas densidades de semeadura: dez e 15 plantas m-1. Adotou-se delineamento experimental de blocos casualizados, com quatro repetições. Quando o feijoeiro esteve presente com as plantas daninhas durante o ciclo, a produtividade dos grãos foi reduzida a 63, 50, 42 e 57% para os tratamentos com espaçamento de 0,45 m, densidades de semeadura de dez e 15 plantas m-1, espaçamento de 0,60 m e densidades de semeadura de dez e 15 plantas m-1, respectivamente. Os períodos anteriores à interferência (PAIs) da cultura foram de 23, 27, 13 e 19 dias após emergência, respectivamente.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The aim of this study was to determine the effects of the use of rosuvastatin in patients with atherosclerosis, in relation to blood parameters of selenium and selenoproteins, and also observe possible changes in gene expression of selenoproteins in these patients. The sample consisted of 27 adult and elderly patients with a clinical diagnosis of coronary artery disease undergoing angioplasty, treated at Natal Hospital Center hospital, Natal, RN. Patients were treated with rosuvastatin 10 mg/day during four months. Anthropometric variables such as body mass index (BMI) and Waist circumference (WC) were measured before and after treatment, as well as lipid profile, blood glucose and liver enzymes (AST and ALT). The diet of the patients was also analyzed using 24-hour diet recall. We analyzed the concentrations of selenium in plasma and erythrocytes, and also the activity of Glutathione Peroxidase and gene expression by Real Time PCR of selenoproteins GPx1, SelP1 and SelN1. Patients had mean age of 61.0 ± 9.4 years, 59.3% were men and 40.7% were women. After four months of treatment there was significant reduction of CA and, according to BMI, most were overweight. The intake of macronutrients, cholesterol, polyunsaturated fatty acids, monounsaturated and saturated was adequate, but the energy and fiber intake was below the recommendations. Regarding the selenium intake was observed a high prevalence of inadequacy. As expected, after treatment with rosuvastatin, a significant reduction in total cholesterol, LDL and glucose, which was not observed for HDL. Selenium concentrations in plasma and erythrocytes showed no changes, keeping within the established cutoffs. We observed a significant increase in GPx enzyme activity and mRNA expression of GPX1 and SEPN1, but not for gene SEPP1. Thus, it was found that treatment with rosuvastatin did not reduce the expression of selenoproteins. More studies are needed to clarify the effects of rosuvastatin on gene expression of selenoproteins in patients with atherosclerosis
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The study had as objective to evaluate the zinc status by means of dietary intake, zinc in plasma and in erythrocytes and the metallothionein gene expression in patients with atherosclerosis in use of rosuvastatin. The research involved 27 adult and elderly patients of both genders with atherosclerosis that were treated with rosuvastatin (10mg/day) during 4 months. We performed the dosage of lipids, glucose, AST and ALT, ultrasensitive C-reactive protein (hsCRP), plasmatic and erythrocyte zinc and 1 and 2 metallothionein gene expression. The assessment of body mass index (BMI) and abdominal circumference (AC) was performed, besides the analysis of dietary intake of patients. The majority of the evaluated patients presented overweight, before and after the treatment, with no significant difference between the times of the study. It was identified that the AC was significantly reduced in the group (p<0.05) after the intervention. The majority of the patients had intake below the recommendation of calories and fibers and above recommendation of proteins. The mono and polyunsaturated fats were adequate for the majority of the patients, however, the saturated fat and cholesterol were consumed in excess by a great part of the individuals. The intake of zinc was inadequate, being noticed an inadequacy of 100% in the male gender and of 84% in the female. After the treatment with rosuvastatin there was a significant reduction in the total cholesterol (TC) and LDL-c (p<0.01) and no alterations were observed in the HDL-c and triacylglycerols. It was also verified that the reduction of glycemia (p<0.05) and of hsCRP (p<0.01). The analysis did not demonstrate significant differences in the plasmatic and erythrocyte zinc concentration after the treatment. There was, after the treatment, reduction of the MT1F gene (p<0.05) without, however, occurring significant alterations in the MT2A gene. The treatment with rosuvastatin was effective in the reduction of TC and LDL-c, and promoted the reduction of inflammatory marker hsCRP. The zinc in the plasma and erythrocyte was not altered by the use of the medication and there was a reduction in the MT1F gene, possibly due to the reduction of inflammation. The majority of patients presented inadequate intake of zinc and this inadequacy did not have relation with the mineral parameters in plasma and erythrocytes or with the metallothionein gene expression
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Spondias sp. (Anacardiaceae), popularly known as cajá-umbu, is an endemic plant from Northeastern Brazil, where their leaves are widely used in folk medicine to treat inflammatory processes, while their fruits have a great agro industrial potential. This study was designed to evaluate hepatoprotective, antinociceptive, antioxidant, antimicrobial and anti-inflammatory properties, as well as the acute toxicity and repeated dose 28, using a methanolic extract (MES), a fraction rich in flavonoids (FRF) and a precipitate from Spondias sp.leaves. The antioxidant activity of them was valued to evaluate their free radical scavenger capacity by DPPH test, whereas MES and FRF were used to evaluate while the preventive action on carbon tetrachloride (CCl4)-induced hepatotoxicity. Seven groups (n=5) of female Wistar rats were used as follows: control group, CCl4-intoxicated group treated with EMS (500 mg/kg) for 7 days, three CCl4-intoxicated groups treated with FRF (25, 50 and 75 mg/kg) for 7 days and the CCl4-intoxicated group treated with Legalon ® (silimarina; (phytotherapeutic reference) (50 mg/kg; 7 days). MES and FRF showed a protective action against liver injury induced by CCl4, being observed a significant reduction of serum enzyme activity marker of liver damage (alanine transaminase and aspartate transaminase). On the other hand, the lipid peroxidation (SRAT) decrease, as well as the increase of glutathione content and enzyme activity of antioxidant defense system (SOD, CAT, GPx) toward near normal values indicated the ability of EMS to restore the oxidative imbalance induced by CCl4. The histological analysis confirmed the hepatoprotection, compared to degenerative changes in CCl4-treated group. This hepatoprotetor effect was similar to that shown by Legalon®. The in vitro high antioxidant capacity of extract (93.16 ± 1.00%) showed analogous results to those obtained by Carduus marianus BHT (reference standard). This fact explains the obtained results in vivo. Although no antimicrobial activity was detected, EMS and FRF promoted the antinociceptive effect induced in the second phase by the intraplantar formalin test, evidencing the anti-inflammatory action; confirmed by the carrageenan-induced peritonitis model. The evaluation of the mechanical allodynia (CFA a 80%) demonstrated the involvement of the Spondias sp. chemical composition in the anti-inflammatory activity toward the acute processes. The acute exposure and repeated dose during 28 days did not produce significant changes in the parameters that evaluate toxicity. Together the experimental results reveal, that Spondias sp. leaf extracts have a promising potential in pharmaceutical area, and due to its non-toxic condition present efficiency and security