90 research outputs found

    Polymeric micelles containing resveratrol: development, characterization, cytotoxicity on tumor cells and antimicrobial activity

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    Antimicrobial and antitumor activities of resveratrol, a compound found mainly in grapes, have already been demonstrated. However, its low bioavailability is a limiting factor for therapeutic application. Polymeric micelles can be an approach to solve this problem since they can encapsulate hydrophobic substances. We developed and characterized micellar formulations containing resveratrol and evaluated their cytotoxic and antimicrobial effects. The formulations were prepared by the cold dispersion method with different concentrations of F127 (5 or 10% w/w) and resveratrol (500 or 5000 µM). The formulations were characterized according to size, polydispersity index, pH, encapsulation rate and in vitro release. Cytotoxic effect was evaluated on a bladder cancer cell line and antimicrobial effect was evaluated on E. coli, S. aureus and C. albicans. One of the formulations (10% w/w of F127 and 5000 µM of resveratrol) was a monodispersed solution with high encapsulation rate, thus it was chosen for the cytotoxicity and antimicrobial assays. MS10+RES-3 was able to preserve the antimicrobial and cytotoxic activity of resveratrol. This is the first study that evaluated antimicrobial potential and cytotoxicity of micelles containing resveratrol on bladder cancer cells and the results showed that micellar nanostructures could ensure the maintenance of the biological activity of resveratrol

    Chemical constituents and allelopathic activity of the essential oil from leaves of Eremanthus erythropappus.

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    The essential oil from leaves of Eremanthus erythropappus (DC.) MacLeish (Asteraceae) collected in South-eastern Brazil was extracted using a combination of water and steam distillation and investigated by chromatography/mass spectrometry (GC-MS). The sesquiterpene hydrocarbons were predominant (46.6%), followed by oxygenated sesquiterpenes (29.3%) and monoterpene hydrocarbons (18.8%). The major compounds were (?)-caryophyllene (29.3%), caryophyllene oxide (22.1%) and ?-pinene (12.8%). The allelopathic activity of E. erythropappus essential oil on the seed germination and radicle length of seedlings was evaluated in lettuce (Lactuca sativa L.), tomato (Lycopersicum esculentum Mill.) and in two field weeds (field mustard ? Brassica rapa L. and hairy beggarticks ? Bidens pilosa L.). Among the weed species tested, the most significant inhibition of seed germination was observed in field mustard, as measured by the half?minimal inhibitory concentration, IC50 (IC50?=?26.5??L mL?1), and the most significant inhibitory effect on radicle length of seedlings was observed in seedlings of hairy beggarticks (IC50?=?16.3??L mL?1). In contrast, the lowest allelopathic effects of E. erythropappus essential oil on seed germination and radicle length of seedlings were observed in tomato (IC50?=?>200??L mL?1 and 130.1??L mL?1 respectively) and lettuce (IC50?=?97.1??L mL?1 and 35.1??L mL?1 respectively). These results revealed significant allelopathic potential of E. erythropappus essential oil against weeds, but minimal effect on lettuce and tomato germination, and thus suggests it is feasible to use E. erythropappus sustainability as an eco-friendly bioherbicide in cropping settings

    Desenvolvimento de nanoemuls?o fotoprotetora de Passiflora edulis.

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    O surgimento de in?meras doen?as, como o c?ncer de pele e o fotoenvelhecimento est?o relacionados com a radia??o solar em excesso, constituindo um consider?vel problema de sa?de p?blica. O desenvolvimento fotoprotetores t?m sido estimulado com o intuito de proteger a pele dos efeitos nocivos da radia??o ultravioleta (UV). O objetivo do presente trabalho foi avaliar o potencial fotoprotetor (FPS) do extrato etan?lico bruto (EB) de Passiflora edulis; a associa??o com a nanoemuls?o e a atividade fotoprotetora; al?m de caracterizar as nanoemuls?es quanto ao di?metro m?dio, ?ndice de polidispers?o (IP) e potencial zeta. Foram desenvolvidas tr?s nanoemuls?es t?picas para incorpora??o do extrato a 0,5%. As nanoemuls?es foram avaliadas visualmente quanto ? apar?ncia macrosc?pica 24 horas ap?s o preparo, observando a presen?a ou n?o de sinais de instabilidade, como precipita??o e separa??o de fases. Na formula??o A, B e C, o extrato bruto foi solubilizado em Croduret, PEG e DMSO, respectivamente. O FPS foi determinado pelo m?todo espectrofotom?trico. Visualmente, a formula??o A incorporou 100% do EB adicionado e apresentou-se est?vel ap?s 24 horas. Entretanto, as formula??es B e C n?o incorporaram todo o EB adicionado, ocasionando em separa??o das nanoemuls?es em duas fases. O FPS foi determinado para o extrato etan?lico bruto e para a formula??o A. Para o extrato etan?lico, o valor de FPS encontrado foi igual 11 e para a formula??o A antes e ap?s a incorpora??o do EB, FPS 4 e FPS 20, respectivamente. O di?metro m?dio da formula??o A sem e com extrato foi de 70,24 ? 0,12 nm e 72,10 ? 0,39 nm, respectivamente, indicando que n?o houve mudan?a significativa do di?metro m?dio da nanoemuls?o ap?s a incorpora??o do EB. O IP da formula??o A antes e ap?s a adi??o de EB foi inferior a 0,3, caracterizando as mesmas como monodispersas. Os resultados apresentados mostraram que a associa??o do EB ? formula??o A resultou no aumento da sua atividade fotoprotetora

    Preparation and characterization of a quercetin-tetraethyl ether-based photoprotective nanoemulsion.

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    Although Quercetin absorbs in the UVA/UVB electromagnetic region, it is limited for applications as a UV filter due to its low lipophilicity and capacity to penetrate the epidermis. In order to overcome this limitation, we synthetized and evaluated the photo protective properties of a derivative obtained from Quercetin. The derivative was prepared by alkylation of Quercetin with iodoethane and characterized by IR and NMR spectroscopy. The in vitro Solar Protection Factor was determined by the Mansur method and the cytotoxicity was evaluated using hepatocellular cell (Hep G2) cells. Finally, Quercetin and the corresponding derivative were incorporated in nanoemulsions. Nanoemulsions with particles sizes between 53 and 73 nm were obtained, and polydispersity indexes were around 0.1, indicating good homogeneity of the nanoemulsion particles. The cell viability study for the Quercetin derivative indicated a very low cytotoxicity profile. The chemical modification of Quercetin resulted in a promising compound with improved properties desirable for skin penetration and incorporation into sunscreen formulations

    Definições para a padronização da pesquisa de auto-anticorpos contra constituintes do núcleo (FAN HEp-2), nucléolo, citoplasma e aparelho mitótico e suas associações clínicas

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    OBJECTIVE: The Second Brazilian Consensus on Antinuclear Antibodies (ANA) in HEp-2 Cells approved and extended the decision trees developed during the First Brazilian Consensus in order to also offer information about mixed patterns of fluorescence. METHODS: Since this test elicits reactions not only to nuclear autoimmune antigens but also to different cell compartments, new denominations for the test were approved. Results and CONCLUSIONS: These new denominations encompass variations on the autoantibody testing against the nucleus (ANA HEp-2), nucleolus, cytoplasm, and mitotic apparatus issue. Furthermore, major clinical associations were described for each immunofluorescent pattern, facilitating the interpretation of laboratory results in the clinical practice.OBJETIVO: O Segundo Consenso Brasileiro de Fator Antinuclear (FAN) em Células HEp-2 ratificou os algoritmos de decisão para leitura dos padrões do FAN na imunofluorescência indireta vistos na primeira edição do Consenso Brasileiro, adicionando ainda um novo algoritmo relacionado com os padrões mistos. MÉTODOS: Tendo em vista a habilidade do teste em detectar autoantígenos nos distintos compartimentos celulares, e não apenas no núcleo, propõe-se novas denominações para este exame laboratorial. RESULTADOS E CONCLUSÕES: Como novas denominações algumas sugestões foram igualmente aceitas, dentro do tema pesquisa de auto-anticorpos contra constituintes do núcleo (FAN HEp-2), nucléolo, citoplasma e aparelho mitótico. Foram abordadas as principais relevâncias clínicas com os padrões de FAN descritos, facilitando o melhor uso do ensaio pelo médico.FMUSPUNIFESPBio-Rad Laboratório BrasilHospital Geral de GoiâniaBiomédicaUniversidade Federal de UberlândiaUFMG HCPUCRS HCNew Life Produtos HospitalaresUniversidade Católica de GoiásFMUSP HC Laboratório CentralPatologista ClínicaFMUSP HCFrischmann Aisengart Unidad InmunologíaUniversidade Católica de Goiás Laboratório de Auto-ImunidadeExame Medicina LaboratorialFMUFG HC Laboratório de Imuno-Reumatologia e HLALab. Santa LuziaMedivax/BionHSPE/SPUniversidade Católica de Goiás Laboratório da Área de SaúdeFarmacêutica-BioquímicaUniv. Fed. Mato GrossoFMUFG Serviço de ReumatologiaHospital Durand Unidad InmunologíaLaboratório ClínicoUFRGS HCPA Serviço de ReumatologiaUERJ FCMUFMG FMHospital Universitário de Brasília Laboratório de ReumatologiaUNIFESPSciEL

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Forward-central two-particle correlations in p-Pb collisions at root s(NN)=5.02 TeV

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    Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5 2GeV/c. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B. V.Peer reviewe

    Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV

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    Peer reviewe

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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