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Antibacterial enhancement of antibiotic activity by Enterolobium contortisiliquum(Vell.)Morong

Asian Pacific Journal of Tropical Biomedicine 2017年第10期7卷 945-949页

作者： Zildene de Sousa silveira Nair Silva Macêdo Thiago Sampaio de Freitas Ana Raquel Pereira da Silva Joycy Francely Sampaio dos Santos Maria flaviana Bezerra Morais-Braga josé Galberto Martins da Costa Raimundo Nonato Pereira Teixeira Jean Paul Kamdem Henrique Douglas Melo Coutinho Francisco Assis Bezerra da Cunha Laboratorio de Bioprospeccao do Semioarido Universidade Regional do CaririCratoBrazil Laboratorio de Microbiologia e Biologia Molecular Universidade Regional do CaririCratoBrazil Laboratorio de Pesquisas de Produtos Naturais Universidade Regional do CaririCratoBrazil Departamento de Ciencias biologicas Universidade Regional do Cariri-URCACratoCEP:63105-000Brazil Programa de Pos-graduacao em Bioprospeccao Molecular Universidade Regional do Cariri–URCACratoBrazil

Objective: To identify the main chemical classes of compounds from aqueous extract of Enterolobium contortisiliquum(E. contortisiliquum) seed bark and to evaluate its antibacterial activity, as well as its potential to increase the activity of antibiotics against strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia ***: Different classes of compounds in the aqueous extract of E. contortisiliquum were evaluated based on the visual changes in the coloration and the formation of precipitate after the addition of specific reagents. The antibacterial activity of the extract and its potential to increase of antibiotic activity of antibiotics drugs, gentamicin and norfloxacin was determined by using the microdilution ***: Our results demonstrated that the following secondary metabolites were presented in E. contortisiliquum seed bark: flavones, flavonols, xanthones, flavononols,chalcones, aurones, flavones and catechins. The extract itself had very low antibacterial activity against all bacterial strains tested(MIC ≥ 1024 μg/m L), but there was an increase in the antibiotic activity of gentamicin and norfloxacin when combined in the subinhibitory concentration(i.e., MIC/8).Conclusions: Our data suggests that E. contortisiliquum seed bark may be an alternative source for new drugs with the potential to increase antibiotic activity against different strains of bacteria.

关键词： Antibiotic activity Enhancement Synergism Chemical compounds Bioactivity

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Projections of Precipitation Changes in Two Vulnerable Regions of São Paulo State, Brazil

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American Journal of Climate Change 2017年第2期6卷 268-293页

作者： Iracema F. A. Cavalcanti Lucí H. Nunes josé A. Marengo Jorge L. Gomes Virginia P. silveira Marina S. Castellano Center of Weather Forecasting and Climate Studies/National Institute for Space Science (CPTEC/INPE) Cachoeira Paulista S.P. Brazil State University of Campinas (UNICAMP) Cachoeira Paulista S.P. Brazil National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN) S&atilde o josé dos Campos S.P. Brazil

Weather and climate extremes are part of the natural variability. However, the frequency and intensity of precipitation extremes have increased in the globe following the global warming. Extreme precipitation impacts such as landslides and flooding with implications to vulnerability and adaptation are discussed for two regions of the state of S?o Paulo: the Metropolitan Region of Campinas and the Metropolitan Region of the Baixada Santista, located in southeastern South America. Simulations and projections obtained from four integrations of the Regional Eta model are analyzed to investigate the model behavior during the period of 1961-1990 and the projections within the period of 2011-2100. Uncertainties are discussed based on the standard deviation among the model spread. The projections show precipitation increase in the Metropolitan Region of Campinas during DJF for the near and distant future, while there are more uncertainties in the other seasons. In the Metropolitan Region of Baixada Santista, the precipitation increase is projected to all seasons, except JJA, when there is higher uncertainty. Daily rainfall indices suggest an increase of precipitation during the rainy days, but a reduction in the number of rainy days in both locations. The projections show a reduction of light rains and an increase of heavy rains at both regions. The model identifies the South Atlantic Convergence Zone and frontal systems as precipitation patterns associated with extremes in the two locations. The results can be useful for adaptation actions, since the regions are highly populated and have high vulnerabilities.

关键词： Climate Change Precipitation Extremes Vulnerable Regions Precipitation Indices Regional Model

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Gas Exchange and Production of Photosynthetic Pigments of <i>Piper aduncum</i>L. Grown at Different Irradiances

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American Journal of Plant Sciences 2013年第12期4卷 114-121页

作者： Fernanda Ventorim Pacheco Helbert Rezende de Oliveira silveira Amauri Alves Alvarenga Ivan Caldeira Almeida Alvarenga josé Eduardo Brasil Pereira Pinto Jean Marcel Sousa Lira Departamento de Agricultura Geral UFLA-Universidade Federal de Lavras Lavras Brazil Setor de Fisiologia Vegetal Departamento de Biologia UFLA-Universidade Federal de Lavras Lavras Brasil

The species Piper aduncum is a plant with great economic potential, because the essential oil has antimicrobial activity and insecticides. Thus, as the light directly affects photosynthesis process, the present study evaluated the gas exchanges’ variables and photosynthetic pigments’ production of P. aduncum grown under different irradiances. Treatments consisted in environments with 100%, 70% and 50% of irradiance and environments with colored nets (red and blue). After 150 days of culture, photosynthetic activity (A), stomatal conductance (gs) transpiration rate (E), internal CO2 concentration (Ci), deficit vapor pressure (DVP), leaf temperature, concentration of internal/external CO2 (Ci/Ca), carboxylation efficiency (A/Ci) and efficiency water use (A/E) were evaluated. Pigments chlorophyll a, b, carotenoids, total and chlorophyll a/b ratio were also measured. From the observed data, it can be concluded that the species Piper aduncun developed various mechanisms for adaptation to different irradiance conditions. Moreover, it can be inferred that their photosynthetic process is more efficient and has larger spectral intensities of light, with higher efficiency photosynthetic when grown under 70% and 100% of radiation.

关键词： Long Pepper Color Nets Chlorophyll Luminosity Ecoambients

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Theoretical Study of Fully Developed Turbulent flow in a Channel, Using Prandtl’s Mixing Length Model

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Journal of Applied Mathematics and Physics 2018年第4期6卷 677-692页

作者： Luigi A. Antonialli Aristeu silveira-Neto Faculdade de Engenharia Mecanica Universidade Federal de Uberlandia Uberlandia Minas Gerais Brazil

This research used the common decomposition of the velocity and pressure in an average part and a fluctuating part, for high Reynolds number, of the Navier-Stokes equation, which leads to the classic problem of turbulent closure. The Prandtl’s mixing length model, based on the Boussinesq hypothesis and traditionally used for free shear flows, was chosen and adapted for internal flows to solve the closure problem. For channel flows, Johann Nikuradse proposed a model for the Prandtl mixing length. In the present paper, which has an academic character, the authors made a return to the model of the mixing length of Prandtl and the model of Nikuradse, to solve turbulent flows inside a plane channel. It was possible to develop an ordinary differential model for the velocity in the direction of the flow whose solution occurs computationally in a simple but extremely accurate way when compared with Direct Numerical Simulation databases. For the viscous stress on the wall, it was possible to determine the exact mathematical solution of the ordinary differential equation. It is a model of great academic value and even to be used as reference for verification of computational codes destined to the solution of complete numerical and computational models.

关键词： Mixing Length Channel Pipe Turbulent flow

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GTAW焊接过程中熔池发展的数值模拟及与实验结果的比较

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四川大学学报（工程科学版） 2002年第6期34卷 47-51页

作者：杨雪峰 Aristeuda silveira Neto Américo Scotti 四川大学化学工程学院四川成都610065 Universidade Federal de Uberlandia

用描述等离子弧和熔池中的流体流动和传热过程的数学模型对熔池的发展进行了数值模拟。模拟结果和文献中实验结果的比较表明 ,该数学模型能较好地预测熔池的形状和大小。

关键词：焊接过程数值模拟熔池发展 GTAW焊接等离子弧数学模型传热过程

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Cerium Separation from Light Rare Earth Concentrate by Liquid-Liquid Extraction

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World Journal of Engineering and Technology 2016年第3期4卷 129-137页

作者： Thiago silveira Formiga Carlos Antonio de Morais Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) Belo Horizonte Brazil

This work presents an investigation of solvent extraction parameters in order to obtain high purity cerium from a mixture containing other rare earths elements, as an alternative to oxidation and selective precipitation or dissolution. The study was carried out using a sample of sulfuric liquor obtained from the leaching of monazite rich in light rare earth elements (La, Ce, Pr, Nd) provided by INB (Indústrias Nucleares do Brasil S.A.). Experiments were carried out in chloridric, nitric and sulfuric media. The nitric and hydrochloric solutions were prepared by precipitation of the REE from the sulfuric liquor as rare earths oxalate, calcining the precipitate and dissolving it with nitric or hydrochloric acid. The separation of cerium was investigated in its trivalent and tetravalent forms. The parameters investigated were: type and concentration of extractant, type and amount of the oxidizing agent, liquor acidity, and volumetric ratio between organic and aqueous phases. The preference of the organic phase to extract cerium in its oxidized form (IV) over the other rare earths elements was confirmed, allowing the obtainment of a high purity cerium solution. The best results were achieved in nitric medium, with cerium in its tetravalent form, using cationic extractants (P507 or D2EHPA) and a mixture of potassium persulfate and silver chloride as oxidizing agents, yielding over 99% of cerium extraction with over 99% of purity.

关键词： Cerium Cerium Extraction Cerium Oxidation Rare Earths Elements

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Inductors of Resistance and Their Role in Photosynthesis and Antioxidant System Activity of Coffee Seedlings

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American Journal of Plant Sciences 2014年第25期5卷 3710-3716页

作者： Luiz Henrique Monteiro Fernandes Helbert Rezende de Oliveira silveira Kamila Rezende Dázio de Souza Mário Lúcio Vilela de Resende josé Donizeti Alves Department of Plant Pathology Federal University of Lavras—UFLA Lavras Brazil Agricultural Reasearch Company of Minas Gerais—EPAMIG Campus of Federal University of Lavras—UFLA Lavras Brazil Department of Biology Federal University of Lavras—UFLA Lavras Brazil

We investigated the effects of formulations based on phosphite products on gas exchange and activity of antioxidant enzymes in coffee plants. Seedlings of the Mundo Novo cultivar were submitted to various treatments composed of different formulations of with potassium phosphite (ADB 120), manganese phosphite (Reforce Mn), and fungicide (PrioriXtra®). For coffee seedlings, the combination of potassium phosphite and citrus by-products, isolated or in a combination with other products elicited the antioxidant system. Besides the high activity of antioxidant enzymes, the photosynthetic rates were higher than other treatments. The better performance of coffee seedlings treated with those formulations occurred even in absence of pathogens.

关键词： Coffea arabica Superoxide Dismutase Ascorbate Peroxidase Catalase

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Leukotriene-A4-Hydrolase and Basic Aminopeptidase Activities Are Related with Collagen-Induced Arthritis in a Compartment-Dependent Manner

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Open Journal of Rheumatology and Autoimmune Diseases 2013年第4期3卷 255-262页

作者： Mariana Trivilin Mendes Paulo flavio silveira Laboratory of Pharmacology Unit of Translational Endocrine Physiology and PharmacologyInstituto ButantanSao PauloBrazil Department of Physiology Instituto de BiociênciasUniversidade de Sao PauloSao PauloBrazil

Objective: Previous study demonstrated the involvement of basic aminopeptidase (APB) activity in the development of collagen-induced arthritis (CIA). Two zinc dependent metalloenzymes (EC 3.***.11.6 and EC 3.***.2.6) are known to exhibit concomitantly APB and leukotriene-A4-hydrolase (LT-A4-H) activities. Influence of the interrelationship between both activities on arthritic processes, however, is presently uncertain. This study aimed to compare these activities in CIA. Methods: CIA was induced in rats and arthritis was assessed macroscopically. Ultracentrifugation was used to separate soluble (S) and solubilized membrane-bound (M) fractions from peripheral blood mononuclear cells (PBMCs) and synovial tissue (ST). Enzyme immunoassay was used to measure LT-A4-H activity, and Real Time Polymerase Chain Reaction was used for evaluating EC 3.***.11.6 and EC 3.***.2.6 gene expressions. Results: The existence of genes for EC 3.***.2.6 and EC 3.***.11.6 was demonstrated in the ST. Compared with control, LT-A4-H activity increased in synovial fluid (SF) and in S-PBMCs of CIA-arthritic and CIA-resistant and in M-ST of CIA-resistant, while it decreased in M-PBMCs of CIA-arthritic and CIA-resistant. In all these locations APB activity remained unchanged or inversely correlated with LT-A4-H activity. Conclusions: LT-A4-H and APB activities in joint-related samples are associated, for the first time, with EC 3.***.2.6 and EC 3.***.11.6 genes, exhibiting a compartment-dependent differential modulation of their specificity, efficiency and/or affinity or an inverse concurrent pattern. Changes in LT-A4-H activity have implications for development or resistance to arthritis in CIA model with a potential to be a diagnostic tool.

关键词： Aminopeptidase Ether Hydrolase Bifunctional Enzyme Eicosanoids

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Assessing the prognosis of cirrhotic patients in the intensive care unit:What we know and what we need to know better

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World Journal of Hepatology 2021年第10期13卷 1341-1350页

作者： Fernando da silveira Pedro H R Soares Luana Q Marchesan Roberto S A da Fonseca Wagner L Nedel Programa de Pos-Graduacao em Pneumologia Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil Intensive Care Unit Grupo Hospitalar ConceiçãoPorto Alegre 91430835Brazil Programa de Pos-Graduacao em Neurociencias Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil Programa de Pos-Graduacao em Ciencias da Saude Universidade Federal de Santa MariaSanta Maria 97105900Brazil Programa de Pos-Graduacao em Bioquimica Universidade Federal do Rio Grande do SulPorto Alegre 91430835Brazil

Critically ill cirrhotic patients have high in-hospital mortality and utilize significant health care resources as a consequence of the need for multiorgan *** this fact,their mortality has decreased in recent decades due to improved care of critically ill ***-on-chronic liver failure(ACLF),sepsis and elevated hepatic scores are associated with increased mortality in this population,especially among those not eligible for liver *** score is superior to another in the prognostic assessment of these patients,and both liver-specific and intensive care unit-specific scores have satisfactory predictive *** sequential assessment of the scores,especially the Sequential Organ Failure Assessment(SOFA)and Chronic Liver Failure Consortium(CLIF)-SOFA scores,may be useful as an auxiliary tool in the decision-making process regarding the benefits of maintaining supportive therapies in this population.A CLIF-ACLF>70 at admission or at day 3 was associated with a poor prognosis,as well as SOFA score>19 at baseline or increasing SOFA score>*** studies addressing the prognostic assessment of these patients are necessary.

关键词： Cirrhosis Extrahepatic organ failure Organ replacement therapy Mortality Prognostic scores Chronic Liver Failure Consortium-Sequential Organ Failure Assessment Sequential Organ Failure Assessment Model for End-stage Liver Disease

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Pramipexole, a dopamine D3/D2 receptor-preferring agonist, attenuates reserpine-induced fibromyalgia-like model in mice

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Neural Regeneration Research 2022年第2期17卷 450-458页

作者： Carlos Pereira Martins Rodrigo Sebben Paes Gabriela Mantovani Baldasso Eduarda Gomes Ferrarini Rahisa Scussel Rubya Pereira Zaccaron Ricardo Andrez Machado-de-Avila Paulo Cesar Lock silveira Rafael Cypriano Dutra Laboratory of Autoimmunity and Immunopharmacology Department of Health SciencesCampus AraranguaUniversidade Federal de Santa CatarinaAraranguáSCBrazil Post-Graduate Program of Neuroscience Center of Biological SciencesUniversidade Federal de Santa CatarinaFlorianópolisSCBrazil Laboratory of Experimental Physiopathology Program of Postgraduate in Science of HealthUniversidade do Extremo Sul CatarinenseCriciumaSCBrazil

Fibromyalgia(FM) is a complex pathology described as persistent hyperalgesia including somatic and mood dysfunctions, depression and anxiety. Although the etiology of FM is still unknown, a significant decrease in biogenic amines is a common characteristic in its pathogenesis. Here, our main objective was to investigate the role of dopamine D3/D2 receptor during the reserpine-induced pain in mice. Our results showed that pramipexole(PPX) – a dopaminergic D3/D2 receptor agonist – inhibited mechanical allodynia and thermal sensitivity induced by reserpine. Relevantly, PPX treatment decreased immobility time and increased the number of grooming in the forced swimming test and splash test, respectively. Animals that received PPX remained longer in the open arms than the reserpine group using elevated plusmaze apparatus. The repeated PPX administration, given daily for 4 days, significantly blocked the mechanical and thermal allodynia during FM model, similarly to pregabalin, although it failed to affect the reserpine-induced thermal nociception. Reserpine administration induced significant downregulation of dopamine concentration in the central nervous system, and repeated treatment with PPX restored dopamine levels in the frontal cortex and spinal cord tissues. Moreover, PPX treatment inhibited oxidants production such as DCFH(2′,7′-dichlorodihydrofluorescein) and nitrite, also decreased oxidative damage(carbonyl), and upregulated the activity of superoxide dismutase in the spinal cord. Together, our findings demonstrated the ability of dopamine D3/D2 receptor-preferring agonist in reducing pain and mood dysfunction allied to FM in mice. All experimental protocols were approved by the Universidade Federal de Santa Catarina(UFSC) Ethics Committee(approval No. 2572210218) on May 10, 2018.

关键词： dopamine dopaminergic system fibromyalgia hyperalgesia pain pramipexole reserpine

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