143 research outputs found
Preparação de extratos de própolis dos Açores e avaliação das suas atividades antimicrobiana e antioxidante
Própolis é uma substância resinosa natural produzida pelas abelhas a partir de material
de origem vegetal recolhido na flora circundante, sendo utilizado posteriormente na
construção e reparação das suas colmeias [1]. Este produto apresenta uma composição
química muito complexa e também muito diversa, bem como diversas atividades
biológicas de interesse [2,3]. No presente trabalho estudaram-se cinco amostras de
própolis recolhidas em 2010, na ilha Terceira (Açores, Portugal) com o objetivo de avaliar
a sua capacidade antioxidante e as suas propriedades antimicrobianas. Para o efeito
prepararam-se extratos etanólicos das amostras em estudo. O potencial antioxidante foi
avaliado através de uma técnica eletroquímica, a voltametria. A atividade antimicrobiana
foi estimada pelo método de incorporação dos extratos em placas com meio de cultura
apropriado, utilizando como indicadores de suscetibilidade um painel de leveduras e
bactérias de interesse em diferentes áreas.
Em relação à atividade antimicrobiana, os extratos foram mais ativos contra leveduras do
que contra bactérias, e genericamente mais ativos contra as bactérias Gram-negativas
que contra as Gram-positivas. No entanto, os extratos mais ativos contra leveduras não
foram os mais eficazes contra bactérias, sugerindo modos de ação distintos sobre
procariotas e eucariotas. Os resultados sugerem ainda uma relação entre algumas
características macroscópicas das amostras, como por exemplo a cor, o aroma e a
dureza, e a sua atividade antifúngica, o que poderá constituir um importante marcador.
Quanto ao potencial antioxidante, verificou-se existirem também diferenças entre os cinco
extratos estudados, apresentando o extrato 4 maior atividade antioxidante, enquanto que
os extratos 1 e 3 apresentam capacidade antioxidante semelhante. A inexistência de uma
correlação entre a capacidade antioxidante e os espetros de atividade antimicrobiana
revela que os compostos responsáveis por estas bioatividades sejam distintos.
Em conclusão, apesar das amostras serem provenientes de uma região relativamente
circunscrita, existem diferenças significativas quanto à composição e bioatividades
analisadas
Antimicrobial and antioxidant properties of propolis ethanol extracts from Terceira Island (Azores, Portugal)
Publicado em "Planta Medica, vol. 80, nr. 16 (2014) P1L17" (Book of abstracts)Bees produce a resinous mixture named propolis known to have several functions in the beehive,
namely structural and sanitary [1,2]. Propolis presents a rich and complex chemical composition,
imparted from the several plant materials collected, and several compounds and extracts have been
associated with biological activities of high interest [3].
This study focuses on the antimicrobial activity and antioxidant capacity of ethanolic extracts (EE)
obtained from propolis samples collected in 2010, in five different areas of the Terceira Island (Azores
Archipelago).
Antimicrobial activity was evaluated by dilution assay incorporating different EE concentrations in solid
media. Bacteria and yeasts of clinical and agrofood relevance were used as indicators of susceptibility.
The results showed that Gram-positive bacteria displayed more resistance (best MIC value 200 µg/ml)
than the Gram-negative (100 µg/ml). Extracts with higher antibacterial activity (e.g. EE4 and EE5) were
generally distinct from those with greater activity against yeast (EE1), but species-specific
susceptibilities and extract-specific efficacies against particular microorganisms were also observed,
only EE1 was effective against S. epidermidis. A relationship between propolis macroscopic
characteristics (colour, hardness and odour) and its antifungal activity was noticed. If confirmed for a
broader range of samples, this relationship may constitute an important diagnostic tool.
The antioxidant capacity was assessed using cyclic voltammetry [4]. EE4 and EE5 showed the highest
antioxidant capacities (39.6 and 23.5 mM eq. gallic acid, respectively), in agreement with results from
the antimicrobial assays. Chemical characterization of all EE are underway.
Despite being collected in a somewhat confined geographic area propolis samples exhibited diverse
antimicrobial activities with different efficiencies and antioxidant capacities
Developing a Compost Quality Index (CQI) based on the electrochemical quantification of Cd (HA) reactivity
The present work demonstrates the use of Cd2+ as a reactivity probe of the fulvic acids (FAs), humic acids (HAs) and dissolved organic matter (DOM) compost extracts. Significant differences were observed between the extracts, with the HA extract showing the highest reactivity. Comparing the different composts, the largest reactivity variation was again observed for HA then FA and finally DOM extracts. The Cd2+ binding extent was used to calculate the quality of composts and compared with a reference of uncomposted organic fertiliser (FLW), leading to the definition of an operational scale of compost quality. The parameter equivalent mass of fertiliser (mEF) was used for this scale sorted the seven composts from 0.353 to 1.09 kg FLW, for compost of sewage sludge (CSS) and vermicompost of domestic waste (CVDW), respectively. The significance of this parameter was verified through a correlation analysis between binding extent and the effect of compost application on lettuce crop growth in a field trial. The results demonstrate the potentiality of FA and HA extracts as markers of compost bioactivity and the use of Cd2+ as a reactivity probe.This work was financially supported by the Interreg VA Spain–Portugal Programme (EU)
through the project Res2ValHum (0366_RES2VALHUM_1_P). A.C. Silva acknowledges receipt of a
PhD grant (UMINHO/BD/40/2016) financed by the Operational Programme Norte 2020 (through
the Project “NORTE-08-5369-FSE-000033”). J. Antelo and S. Fiol are also grateful for the financial
support provided by Xunta de Galicia—Consellería de Educación e Ordenación Universitaria de
Galicia (Consolidation of Competitive Groups of Research; GI-1245, ED431C 2022/40)
Success in publication by graduate students in psychiatry in Brazil: an empirical evaluation of the relative influence of English proficiency and advisor expertise
Abstract\ud
\ud
Background\ud
This study evaluates the success of graduate students in psychiatry in an emerging country, in terms of the quantity and quality of their publication productivity (given by the number of papers and impact factors of the journals in which they publish). We investigated to what extent student proficiency in English and the scientific capabilities of academic advisors predict that success.\ud
\ud
\ud
Methods\ud
Our sample comprised 43 master’s and doctoral students in psychiatry (n = 28 and n = 15, respectively) at the University of São Paulo School of Medicine, in São Paulo, Brazil. We collected information about their knowledge of English and the ways in which they wrote their articles to be submitted to periodicals published in English. Multiple regression analyses were carried out in order to investigate the influence English proficiency, h-index of supervisors and use of language editing assistance had on the number and impact of student publications.\ud
\ud
\ud
Results\ud
Although 60% of students scored ≥80 (out of 100) on English tests given at admission to the graduate program, 93.09% of the sample used some form of external editing assistance to produce their papers in English. The variables “number of publications” and “impact factor of journals” were significantly related to each other (r = 0.550, p < 0.001). Multiple regression analysis revealed that the impact factor of periodicals where students published their articles as first authors correlated significantly not only with student proficiency in English at admission (p = 0.035), but also with the degree of language editing assistance (p = 0.050) and the h-index of the academic advisor (p = 0.050).\ud
\ud
\ud
Conclusions\ud
Albeit relevant, knowledge of English was not the key factor for the publication success of the graduate students evaluated. Other variables (h-index of the advisor and third-party language editing assistance) appear to be also important predictors of success in publication.Article with resources from PROEX/CAPE
Let there be light...
“Let there be light...” is a project in the scope of the International Year of Light 2015 (IYL 2015) targeted at children of the first school grade.
Basically, it comprises nine recreational - scientific workshops that last for approximately 90 minutes. Each workshop is dedicated to a different topic, namely: bioluminescence, mineral observation, the rainbow, light-shadow contrast, battery production, just to name a few, and is designed, in differ- ent approaches, by a distinct team of scientists familiar to the scientific area focused. The activity starts with the dramatized storytelling of a children’s story related to the scientific subject and performed by the team of the public library expert in this area. This moment takes place in an almost magical environment opening the door to the science topic light-related that would be focused later on. In the third part of the workshop, the children are invited to produce plastic works (e.g. drawings, constructions and models) inspired in what they have learned, and that are to be collected in a public exhibition held at the same institution at the end of the project.
In the present work, besides the description of the experience, you can find the critical analysis of the activity and the evaluation of the action by all the actors involved (project team and children/teachers that attended the workshops).info:eu-repo/semantics/publishedVersio
Potent Antiretroviral Therapy for Human Immunodeficiency Virus Infection Increases Aortic Stiffness
Background: Highly active antiretroviral therapy for AIDS is known to increase cardiovascular risk, but the effects of potent antiretroviral agents according to gender are unknown. Objective: The present study evaluated the impact of HIV infection treatment on aortic stiffness according to gender. Methods: From university-affiliated hospitals, we recruited 28 AIDS patients undergoing highly active antiretroviral treatment (HAART), 28 treatment-naive HIV-infected patients, 44 patients with type 2 diabetes, and 30 controls. Aortic stiffness was determined by measuring pulse wave velocity (PWV) using a validated and non-invasive automatic device. Results: The crude mean PWV values and 95% confidence intervals (95% CI) for HAART, diabetics, and controls were 9.77 m/s (95% CI 9.17-10.36),, 9.00 m/s (95% CI 8.37-9.63), 9.90 m/s (95% CI 9.32-10.49), and 9.28 m/s (95% CI 8.61-9.95), respectively, for men (P-value for trend = 0.14), and 9.61 m/s (95% CI 8.56-10.66), 8.45 m/s (95% CI 7.51-9.39), 9.83 (95% CI 9.21-10.44), and 7.79 m/s (95% CI 6.99-8.58), respectively, for women (P-value for trend <0.001). Post-hoc analysis revealed a significant difference between the mean PWV values in the HAART group and controls in women (P-value <0.01). After adjusting for other potential covariates, including systolic blood pressure and diabetes, these results did not change. The findings indicate that the impact of HAART treatment on aortic stiffness was amplified in women with hypertension, dyslipidemia, and metabolic syndrome. Conclusion: Potent anti-retroviral agents used in the treatment of HIV infection increases aortic stiffness, mainly among women with higher cardiovascular risk. (Arq Bras Cardiol 2012;99(6):1100-1107)Fundamento: Sabe-se que a terapia antirretroviral altamente potente para Aids reconhecida aumenta o risco cardiovascular, mas os efeitos dos agentes antirretrovirais de acordo com o gênero ainda são desconhecidos. Objetivo: O presente estudo avaliou o impacto do tratamento para o vírus da imunodeficiência humana (HIV) na rigidez\ud
aórtica de acordo com o gênero. Métodos: Foram recrutados 28 pacientes com Aids submetidos à terapia antirretroviral altamente potente (HAART), 28 pacientes\ud
infectados pelo HIV virgens de tratamento, 44 pacientes com diabetes tipo 2, e 30 controles. A rigidez aórtica foi determinada pela medição da Velocidade da Onda de Pulso (VOP), utilizando um equipamento automático validado e não invasivo. Resultados: Os resultados médios brutos da VOP (e intervalo de confiança de 95%) para participantes nos grupos terapia antirretroviral potente, HIV virgem de tratamento, diabéticos, e controles foram 9,77 m/s (9,17-10,36), 9,00 m/s (8,37-9,63), 9,90 m/s (9,32-10,49) e 9,28 m/s (8,61-9,95), respectivamente, para os homens (p de tendência = 0,14) e 9,61 m/s\ud
(8,56-10,66), 8,45 m/s (7,51-9,39), 9,83 (9,21-10,44) e 7,79 m/s (6,99-8,58), respectivamente, para as mulheres (p valor de tendência < 0,001). Análises post-hoc revelaram uma diferença significativa entre os valores médios de VOP no grupo com HAART e controles em mulheres (p < 0,01). Ajustes para as demais covariáveis potenciais, incluindo pressão arterial sistólica e diabetes, não alteraram esses resultados. Os achados indicam que o impacto do tratamento com HAART na rigidez aórtica foi amplificado nas mulheres com hipertensão, dislipidemia e síndrome metabólica. Conclusão: Agentes antirretrovirais potentes utilizados no tratamento da infecção pelo HIV aumentam a rigidez da aorta, especialmente em mulheres com maior risco cardiovascular. (Arq Bras Cardiol 2012;99(6):1100-1107)FAPESPFAPES
Terapia antirretroviral altamente eficaz para infecção pelo vírus da imunodeficiência humana aumenta a rigidez aórtica
Cigarette smoke induces miR-132 in Th17 cells that enhance osteoclastogenesis in inflammatory arthritis
Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by joint destruction and severe morbidity. Cigarette smoking (CS) can exacerbate the incidence and severity of RA. Although Th17 cells and the Aryl hydrocarbon receptor (AhR) have been implicated, the mechanism by which CS induces RA development remains unclear. Here, using transcriptomic analysis, we show that microRNA-132 is specifically induced in Th17 cells in the presence of either AhR agonist or CS-enriched medium. miRNA-132 thus induced is packaged into extracellular vesicles produced by Th17 and acts as a proinflammatory mediator increasing osteoclastogenesis through the down-regulation of COX2. In vivo, articular knockdown of miR-132 in murine arthritis models reduces the number of osteoclasts in the joints. Clinically, RA patients express higher levels of miR-132 than do healthy individuals. This increase is further elevated by cigarette smoking. Together, these results reveal a hitherto unrecognized mechanism by which CS could exacerbate RA and further advance understanding of the impact of environmental factors on the pathogenesis of chronic inflammatory diseases
Medical assessments and measurements in ELSA-Brasil
Este artigo descreve os exames clínicos realizados no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Alguns deles (antropometria, pressão arterial e índice tornozelo-braquial) já têm uso clínico consolidado. Outros, como a velocidade de onda de pulso, variabilidade da frequência cardíaca e medida da espessura médio-intimal de carótidas, carecem de valor de referência na população brasileira não doente e podem constituir preditores importantes de desfechos cardiovasculares. A medida da pressão arterial após manobra postural foi incluída no ELSA-Brasil porque foi pouco testada em estudos epidemiológicos. O ELSA-Brasil inovou na realização do índice tornozelo-braquial, ao usar um aparelho automático em substituição à coluna de mercúrio na medida da pressão arterial, e também na medida do diâmetro ântero-posterior do lobo direito do fígado pela ultrassonografia, proposta para avaliação quantitativa da doença hepática gordurosa não-alcoólica. Os participantes são indivíduos mais jovens (a partir dos 35 anos) do que em outras coortes focadas no estudo da aterosclerose subclínica. A inclusão de indivíduos mais jovens e a diversidade dos exames realizados tornam o ELSA-Brasil um estudo relevante no contexto da epidemiologia brasileira e internacional.The article describes assessments and measurements performed in the Brazilian Longitudinal Study for Adult Health (ELSA-Brasil). Some assessments including anthropometric assessment, casual blood pressure measurement, and ankle-brachial index have an established clinical application while others including pulse wave velocity, heart rate variability, and carotid intima-media thickness have no established application and do not have reference values for healthy Brazilian population but may be important predictors of cardiovascular outcomes. Blood pressure measurement following postural change maneuver was included in the ELSA-Brasil because it has not been much tested in epidemiological studies. Innovative approaches were developed for assessing the ankle-brachial index using an automatic device instead of the mercury column to measure blood pressure and for assessing the anterior-posterior diameter of the right lobe of the liver by ultrasound for quantitative assessment of nonalcoholic fatty liver disease. All ELSA-Brasil subjects were younger (35 years or more) than those included in other cohorts studying subclinical atherosclerosis. The inclusion of younger individuals and a variety of assessments make the ELSA-Brasil a relevant epidemiology study nationwide and worldwide
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