135 resultados para Fração inspirada de oxigênio


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Medicinal plants have been studied and used in the world. Lantana camara has medicinal properties and it has been used in folk medicine. The aim was to verify the effect of a lantana extract on the labeling of blood constituents with 99mTc, and to evaluate the effect of an aqueous extract of Lantana camara on the morphology of RBC withdrawn from Wistar rats. The results showed that lantana extract has decreased the fixation of radioactivity on the IF-P. This effect was not observed in the BC compartment and in IF-BC. The BC-%ATI was decreased in all concentrations tested when the BC was washed. The osmotic fragility assay and morphological analysis were carried out. In presence of the extract, the data obtained indicated that (i) an increase of the hemolysis and (ii) modifications on the morphology of RBC. These effects of the Lantana camara could be associated with some pharmacological properties of the chemical compounds of this studied extract

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Artemisia vulgaris L..is used in folk medicine and in Traditional Chinese Medicine (TCM). This medicinal plant has been utilized as anticonvulsive, analgesic, antispasmodic effect, rheumatic pains, menstrual dyspepsia, asthenia, epilepsy, hepatitis, fevers, anemia and to expel parasites. In nuclear medicine, blood constituents are labeled with technetium-99m (99mTc) and used as radiopharmaceuticals (radiobiocomplexes). Authors have been described that synthetic and/or natural drugs could modify the labeling of blood constituents with 99mTc. The aim of this work was to evaluate the effects of an aqueous extract of Artemisia vulgaris L. on the labeling of blood constituents with 99mTc. Blood samples withdrawn of Wistar rats were incubated with Artemisia vulgaris L, stannous chloride and 99mTc, as pertechnetate ion. Aliquots of plasma (P) and blood cells (BC) were isolated. Aliquots of P and BC were also precipitated with trichloroacetic acid and soluble (SF) and insoluble (IF) fractions were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) were calculated. Artemisia vulgaris L. extract decreased significantly (p<0.05) the %ATI on BC and on IF-BC. The analysis of the results indicates that the extract could have substances that could interfere on the transport of stannous through the erythrocyte membrane altering the labeling of blood cells with 99mTc. Working in this study was a multidisciplinary group, with Phisical therapists, Biomedicals, Physicals, Pharmacists, Biologists, Statistics and Physicians.

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Introdução: Os hormônios estrogênicos possuem importante papel na defesa contra as espécies reativas do oxigênio, fato que se evidencia na maior incidência de doenças cardiovasculares e neurodegenerativas após a menopausa. O exercício físico melhora as defesas antioxidantes, contudo em altas cargas e em baixas concentrações de estrógeno possui efeito aditivo ao dano oxidativo. O ácido α-lipóico possui uma ampla gama de ação antioxidante e poderia contribuir para diminuição do dano nestas condições. Objetivo: O objetivo deste estudo é caracterizar a ação do ácido α-lipóico sobre a adaptação antioxidante e funções reprodutivas de ratas submetidas a natação moderada. Material e métodos: Os animais foram submetidos a natação diária (1 hora) e sacrificados após 30, 60 e 90 dias. Os animais foram divididos em controles sedentários e exercitados; suplementados (ácido α-lipóico 100mg/Kg/dia) sedentários e exercitados e animais ovariectomizados e suplementados com ácido lipóico. Avaliou-se diariamente o ciclo estral e os seguintes marcadores de estresse oxidativos foram mensurados em fígado e sangue: atividade enzimática da SOD, GPx e CAT, além do SRAT e GSH. Resultados: O protocolo de exercício aumentou a duração do ciclo estral no grupo controle exercitado, sobretudo na fase diestral. Neste mesmo grupo, houve diminuição da lipoperoxidação com melhora da atividade antioxidante da SOD e GPx. O grupo exercitado e suplementado não apresentou alteração na duração do ciclo estral e manteve os benefícios sobre o sistema antioxidante antes observado nos animais exercitados. A suplementação antioxidante juntamente com a natação em períodos superiores a 30 dias, diminuiu o processo de adaptação antioxidante quando comparado aos animais somente exercitados. Nos animais ovariectomizados, o exercício e a suplementação com ácido lipóico não promoveu adaptação antioxidante ao contrário dos demais grupos. Conclusão: O aumento na duração do ciclo estral e a melhora nos marcadores de estresse oxidativo seriam uma resposta adaptativa frente ao exercício moderado. O ácido lipóico impediu a alteração no ciclo induzida pelo exercício, mas preservou a melhoria no sistema antioxidante. A depleção estrogênica provocada pela ovariectomia eleva o potencial de dano oxidativo gerado pelo exercício. A ação antioxidante do LA na presença de estrógeno diminuiu excessivamente o dano oxidativo, comprometendo a adaptação antioxidante a natação. Nos animais ovariectomizados, contudo, o AL promoveu adaptação antioxidante ao exercício

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Radiobiocomplexes are used in nuclear medicine to obtain images and to treat diseases. Blood constituents have been used as radiobiocomplexes. Natural or synthetic products can influence on the labeling of blood constituents with technetium-99m (99mTc), the morphology of red blood cells and on the stannous chloride (SnCl2) action on plasmid DNA. Sambucus australis and Sambucus nigra are used in popular culture for treating diseases. The aim of this work was to evaluate the effects of the extracts of Sambucus australis and Sambucus nigra on the labeling of blood constituents with 99mTc, on morphology of red blood cells of Wistar rats, on the topology of plasmids DNA and the action against the SnCl2 effects on the DNA of plasmids pBSK. On the labeling of blood constituents with 99mTc it was verified that both extracts were capable to decrease significantly the radioactivity in the cellular compartment and in the insoluble fraction of plasma. Sambucus australis also decreased the labeling of insoluble fraction of blood cells with 99mTc. Both extracts did not alter the morphology of red blood cells. Moreover, it was verified that Sambucus nigra did not alter the electrophoretic profile of plasmid DNA, but decreased the effect of SnCl2 on plasmid DNA. These last results sugest a genotoxic effect and a protective action of Sambucus nigra extract against the SnCl2 action on plasmid DNA. This work was developed with the contribution of several Departments of biomedical area of the Hospital Universitário Pedro Ernesto, of the UERJ, characterizing a multidisciplinary experimental research

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Effects of a Cordia salicifolia (porangaba) extract on the labeling of blood cells (BCs) with technetium-99m ((99m)Tc) and on the morphology of red BCs were evaluated. Labeling of cellular and molecular structures with (99m)Tc depends on a reducing agent. Some physical characteristics, as visible absorbance spectrum, electric conductivity, and refractive index of this porangaba extract, were also determined. Blood samples from Wistar rats were incubated with porangaba extract or with 0.9% NaCl (control). Labeling of blood constituents with (99m)Tc was performed. Plasma (P) and BCs, both soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions, were separated. The radioactivity in each fraction was counted, and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, and stained, and the morphology of the red BCs was evaluated. Data showed an absorbance peak at 480 nm and electric conductibility and refractive index concentration-dependent. Porangaba extract decreased significantly (P < .05) the BC, IF-P, and IF-BC %ATI, and no modifications were verified on the shape of red BCs. Analysis of the results reveals that some physical parameters could be useful to aid in characterizing the extract studied. Moreover, it is possible that chemical compounds of this extract could have chelating/redox actions or be capable of binding to plasma and/or cellular proteins

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A resistência microbiana a antimicrobianos tem favorecido a busca por substâncias bioativas provenientes de plantas usadas na medicina popular, com o intuito de se obter novos fármacos com atividade antimicrobiana. Neste estudo, foi proposta a investigação da atividade antibacteriana do óleo-resina de Copaifera duckei e de diferentes extratos da casca de Pseudobombax marginatum, e seus possíveis mecanismos de ação. O potencial inibitório antibacteriano foi avaliado utilizando-se os métodos de difusão e diluição em ágar, e a bioautografia. O mecanismo de ação foi analisado por microscopia eletrônica, no qual se observou alterações na ultraestrutura bacteriana, e por eletroforese em SDS-PAGE, que determinou ação sobre as proteínas das superfícies celulares. A análise química foi realizada pelas técnicas de Espectrometria de massas acoplada ao Cromatógrafo a gás- EM/CG (C. duckei) e Cromatografia Líquida de Alta Eficiência- CLAE (P. marginatum). Entre as bactérias estudadas, B. cereus foi a mais suscetível às plantas em estudo, com concentrações inibitórias mínimas (CIMs) correspondentes a 0,3125 mg/mL para o óleo-resina de copaíba, e 0,5 mg/mL para extrato hidroalcoólico (1:1) e 0,512 mg/mL para a fração butanólica da casca P. marginatum, nos quais pôde-se observar alterações na parede celular do B. cereus, com remoção da camada S, espessamento da parede celular e formação de diversos septos nos centros de divisão celular. A análise química por EM/CG mostrou compostos terpênicos no óleo-resina de C. duckei, tendo como composto majoritário o β-bisaboleno, e a análise por CLAE mostrou a presença de compostos derivados da catequina na casca do P. marginatum. Desta forma, as plantas em estudo mostram um potencial antibacteriano considerável, podendo contribuir tanto na terapia antimicrobiana como na área de alimentos, tendo como um de seus prováveis sítios de ação a parede celular bacteriana

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Trata-se de um coorte prospectivo com amostras de leite de 28 mães da zona rural da Paraíba, durante diferentes dias de amamentação exclusiva, com objetivo de avaliar através do ensaio imunoenzimático a presença de imunoglobulina A secretora (sIgA) total e específica contra antígenos de Escherichia coli enteropatogênica (EPEC) e Shigella flexneri. A reatividade dos anticorpos foi analisada pelo Western blot . Os resultados mostram presença da sIgA em todas as amostras, com medianas no colostro de 8,092 g/L(4,546-17,252) e leite de 0,695g/L (0,020-2,830). As medianas nos títulos de colostro de IgA anti-EPEC foi 41 (1-659) e anti-Shigella flexneri de 18 (1-4727) enquanto no leite anti-EPEC foi de 8 (1-288) e anti-Shigella flexneri de 6 (1-450). Houve grandes variações entre as mães e entre os dias de amamentação. No Western blot os anticorpos sIgA reagiram com proteínas de EPEC e Shigella flexneri, destacando-se a fração antigênica de 94kDa, correspondente a intimina. Os resultados mostram que a presença de sIgA total e de anticorpos IgA contra EPEC e Shigella flexneri no colostro e leite de mães residentes em zona rural, com precárias condições sócioeconômica e sanitárias, não diferem de estudos realizados com populações de área urbana e reforçam a importância do leite materno na defesa contra infecções entéricas. Apesar da ausência na literatura de estudos avaliando o perfil de anticorpos sIgA no leite de mães residentes em zona rural do Brasil, os resultados demonstraram que a presença de sIgA total e de anticorpos IgA contra EPEC e Shigella flexneri no colostro e leite de mães residentes em zona rural, com precárias condições sócio-econômica e sanitárias, não diferem de estudos realizados com populações de área urbana e reforçam a importância do leite materno na defesa contra infecções entéricas

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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Recent years have seen a significant growth in surface modifications in titanium implants, resulting in shorter healing times in regions with low bone density. Among the different techniques, subtraction by chemical agents to increase oxidation has been applied for surface treatment of dental implants. However, this technique is generally unable to remove undesirable oxides, formed spontaneously during machining of titanium parts, raising costs due to additional decontamination stages. In order to solve this problem, the present study used plasma as an energy source to both remove these oxides and oxidize the titanium surface. In this respect, Ti disks were treated by hollow cathode discharge, using a variable DC power supply and vacuum system. Samples were previously submitted to a cleaning process using an atmosphere of Ar, H2 and a mixture of both, for 20 and 60 min. The most efficient cleaning condition was used for oxidation in a mixture of argon (60%) and oxygen (40%) until reaching a pressure of 2.2 mbar for 60 min at 500°C. Surfaces were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM), adhesion and cell proliferation. SEM showed less cell spreading and a larger number of projections orfilopodia in the treated samples compared to the control sample. AFM revealed surface defects in the treated samples, with varied geometry between peaks and valleys. Biological assays showed no significant difference in cell adhesion between treated surfaces and the control. With respect to cell proliferation, the treated surface exhibited improved performance when compared to the control sample. We concluded that the process was efficient in removing primary oxides as well as in oxidizing titanium surfaces

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This study aimed to determine the influence of strength training (ST), in three weekly sessions over ten weeks, on cardiovascular parameters and anthropometric measurements. It is a before and after intervention trial, with a sample composed of 30 individuals. Participants were adults aged between 18 and 40 years, from both sexes and sedentary for at least three months previously. Tests were computed ergospirometry, CRP, PWV and body composition (dependent variables) before and after the experiment. Independent variables, age and sex, were considered in order to determine their influence on the dependent variablesevaluatedend. By comparing the initial cardiovascular parameters with those obtained after intervention in patients undergoing the ST proposed (a Student s t-test was conducted within each group for samples matched to parameters with normal distribution, while the Wilcoxin was applied for those without), there was no significant difference in PWV(p =0469) or PCR(p =0.247), but there was an increase in anaerobic threshold(AT) (p=0.004) and Maximal Oxygen Uptake(VO2max) (p =0.052). In regard to anthropometric measures, individuals significantly reduced their body fat percentage (p<0.001) and fat mass (p<0,001), as well as increasing lean mass (p<0.001). However, no changes were recorded in the waist-to-hip ratio (WHR) (p= 0.777), body mass (p=0.226) or body mass index (BMI) (p =0.212). Findings of this study lead us to believe that the proposed ST, and did not increase the VOP or PCR improves cardiorespiratory capacity and body composition. Devotees of this training can therefore safely enjoy all its benefits without risk to the cardiovascular system

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There is no data about cardiac measurements em Brazilians obtained by CMR. This a muldisciplinary study with the objective of obtaining measurements of the left ventricle (LV) and right ventricle (RV) diastolic diameter (Dd), systolic diameter (Ds), diastolic volume (Dv), systolic volume (Sv), ejection fraction (EF) and myocardial mass in Brazilians. One hundred and seven (54 men and 53 women, mean age of 43.4 ± 13.1 years) asymptomatic individuals without heart disease were submitted to cardiac magnetic resonance (cMR) studies using steady state free precession technique. The means and standard deviations of the parameters of the LV and RV were respectively: LVDD = 4,8 ± 0,5 cm; LVSD = 3,0±0,6 cm; LVDV = 128,4±29,6 ml; LVSV = 45,2±16,6 ml; LVEF = 65,5±6,3%; LV mass = 95,2±30,8.1 g; RVDD = 3,9±1,3 cm; RVSD = 2,5±0,5 cm; RVDV = 126,5±30,7 ml; RVSV = 53.6±18,4 ml; RVEF = 58.3±8,0.0% and RV mass = 26,1±6,1 g. The masses and volumes were significantly higher in men, except for the LVSV. The RV EF was significantly higher in women. There was inverse correlation between RV systolic volume and with age, being more significant in men. This study describes for the first time benchmarks for cardiac measurements obtained by CMR among asymptomatic Brazilians individuals without heart disease and demonstrated differences according to sex and age

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Introdução: O dano miocárdico na doença de Chagas resulta tanto da ação parasitária quanto da resposta imune do hospedeiro humano. O mimetismo molecular entre proteínas do Trypanosoma cruzi e vários antígenos do hospedeiro tem sido amplamente descrito gerando células T CD8+ e anticorpos autorreativos. Entretanto, a geração dos autoanticorpos e seu papel na imunopatogenia da doença de Chagas ainda não têm sido elucidados, o que nos levou, neste trabalho, a avaliar a produção de imunoglobulina G total (IgGt) e seus isotipos anti-T. cruzi, proteínas cardíacas e sua possível associação com as diferentes formas clínicas da doença de Chagas. Métodos: A produção de IgGt e isotipos foi mensurada pelo método de ELISA no soro de pacientes com as formas clínicas indeterminada (IND, n=72), cardíaca (CARD, n=47) e digestiva/cardio-digestiva (DIG/CARD-DIG, n=12) da doença de Chagas, usando como antígenos as formas epimastigota e tripomastigota do T. cruzi e proteínas cardíacas humana (miosina e troponina T). As amostras de indivíduos não infectados saudáveis (CONT, n= 30) e pacientes com cardiomiopatia isquêmica (ISCH, n=15) foram usadas como controle. Os títulos de autoanticorpos foram correlacionados com parâmetros da função cardíaca obtidos por exames eletrocardiográficos, radiográficos e ecocardiográficos. Resultados: Neste estudo foram incluídos 131 indivíduos sem diferença significativa relativa à idade ou sexo. Destes, 55% foram classificados como IND, 35,9% CARD e 9,1% DIG/CARD-DIG. Os títulos de IgGt foram mais elevados em pacientes com as formas clínicas IND, CARD e DIG/CARD-DIG do que em indivíduos CONT e ISCH usando os antígenos as formas tripomastigotas e epimastigotas do T. cruzi e, proteínas cardíacas humanas. Os pacientes com formas clínicas CARD e DIG/CARD-DIG mostraram a produção mais elevada de IgG total dirigida contra antígenos de tripomastigota e epimastigota do que os IND. Os grupos de pacientes IND e CARD apresentaram uma similar produção de IgG total específica direcionada à miosina e troponina T, e mais elevada do que em indivíduos CONT e ISCH. Há uma correlação negativa entre a produção de anticorpos anti-proteínas cardíacas com a fração de ejeção do ventrículo esquerdo (FEVE) em pacientes chagásicos crônicos. Os pacientes foram agrupados em baixo e alto produtores de autoanticorpos e comparados com a fração de ejeção demonstrando que em pacientes alto produtores de anti-troponina T (p=0.042) e miosina (p=0.013) a FEVE foi mais baixa do que os baixo produtores. A maioria dos pacientes chagásicos produz simultaneamente autoanticorpos direcionados à ambas proteínas cardíacas (r=0.9508, p=0.0001). Conclusões: Estes resultados indicam que os autoanticorpos anti- troponina T e miosina cardíaca parecem induzir redução FEVE e deve ser associado com o desenvolvimento de cardiomiopatia chagásica

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Aim: The aim of this work was to investigate the hypothesis that catechol and 3MC inhibit FADH2-linked basal respiration in mitochondria isolated from rat liver and brain homogenates. Moreover, catechol ability to induce DNA damage in rat brain cells through the comet assay (alkaline single-cell gel electrophoresis assay) was also observed. Methods: Two different catechols were evaluated: pirocatechol (derived from benzene) and 3-methylcatechol (derived from toluene); rat liver and brain homogenates were incubated with 1mM catechol at pH 7.4 for up to 30 minutes. After that, mitochondrial fractions were isolated by differential centrifugation. Basal oxygen uptake was measured using a Clark-type electrode after the addition of 10 mM sodium succinate for a period of 12 minutes. In additional experiments, rat brain cells were treated with 1, 5 and 10mM pirocatechol for up to 20 minutes at 37º C, and submitted to electrophoresis. Results: Catechols (pirocatechol and 3methylcatechol) induced a time-dependent partial inhibition of FADH2-linked basal mitochondrial respiration. Indeed, pirocatechol was able to produce a dosedependent DNA oxidative damage in rat brain cells by 2 and 4 injury levels. These results suggest that reactive oxygen species generated by the oxidation of catechols, induced an impairment on mitochondrial respiration and a DNA damage, which might be related to their citotoxicity. Conclusion: Catechols produced an inhibition of basal respiration associated to FADH2 in isolated liver and brain mitochondria; 3-methylcatechol, at the same concentration, produced similar toxicity in the mitochondrial model. Indeed, pirocatechol induced a DNA damage in rat brain cells, mainly observed in comets formation and consequent DNA degradation

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OBJECTIVE: The aim of this work was to analyse some oxidative stress parameters in patients of Systemic Lúpus Erythematosus. PATIENTS AND METHODS: Determinations of reduced glutathione content in whole blood were carried out. The activity of superoxide dismutase, gluthatione peroxidase and catalase in erythrocytes and the concentration of reactive substances of acid thiobarbituric in plasma of patients female (n =19) with SLE no activity of disease (Mex-SLEDAI < 2), with average ages of 32 ± 11 years, through the spectrophotometrical methods and from healthy individuals (n =30). Statistical data were analyzed by student t-test, p<0,05. RESULTS: Our data indicated a significant decrease on the activity of catalase and significant increase on the concentration of reactive substances of acid thiobarbituric in patients with SLE comparing with healthy individuals. There was no significant difference in other parameters. CONCLUSION: The results showed that oxidative stress has a role in the pathogenesis of the disease in SLE, even in patients without active disease.