In vitro toxicity of latex, its terpenoidal fractions and isolated phorbol esters from Euphorbia umbellata (Pax) Bruyns on monocytic and melanoma cells.

In Brazil, latex from Euphorbia umbellata (African milk tree) has been increasingly used in folk medicine to treat several types of cancer, including melanoma. The effect of lyophilized latex (LL), its hydroethanolic extract (E80), triterpene (F-TRI)- and diterpene (F-DIT)-enriched fractions, along with six isolated phorbol esters from LL and phorbol 12-myristate 13-acetate (PMA) on J774A.1, THP-1, SK-MEL-28, and B16-F10 cell line viability were evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The compounds were identified by 2D-NMR and HRESIMS. The effect of the LL, extract and fractions on cell viability was also assessed through a resazurin reduction assay. At 100 µg/ml, LL, and its fractions moderately inhibited J774A.1 (37.5-59.5%) and THP-1 (12.6-43.6%) metabolism. LL (IC50 70 µg/ml) and F-TRI (IC50 68 µg/ml) were barely more effective against B16-F10 cells, and only F-TRI exerted an inhibitory effect on SK-MEL-28 cells (IC50 66-75 µg/ml). The samples did not effectively inhibit THP-1 growth (IC50 69-87 µg/ml, assessed by MTT). B16-F10 was susceptible to PMA (IC50 53 µM) and two 12-phenylacetate esters (IC50 56-60 µM), while SK-MEL-28 growth was inhibited (IC50 58 µM) by one of these kinds of esters with an additional 4ß-deoxy structure. Synagrantol A (IC50 39 µM) was as effective as PMA (IC50 47 µM) in inhibiting J774A.1 growth in a dose-dependent manner. Furthermore, an in silico study with target receptors indicated a high interaction of the compounds with the PKC proteins. These results provide useful knowledge on the effect of tigliane-type diterpenes on tumor cell from the perspective of medicinal chemistry.

Urgência da geração de conhecimento durante a pandemia de covid-19: um retrospecto sobre a integridade em publicações em saúde / Urgency of knowledge generation during the covid-19 pandemic: a retrospective on health publication integrity / Urgencia de generación de conocimiento durante la pandemia de covid-19: una retrospectiva a la integridad en las publicaciones sobre salud

Durante a pandemia de covid-19, foi observado um aumento expressivo do número de publicações (artigos e preprints), que levou ao rápido compartilhamento de informações e incentivou a discussão sobre a integridade científica na geração do conhecimento durante emergências sanitárias. Nesse sentido, o objetivo deste trabalho foi o de realizar uma breve análise do cenário referente à integridade em pesquisa em publicações em saúde durante a pandemia de covid-19. Para isso, fizemos uma pesquisa documental em sites de organizações com histórico de promoção da cultura da integridade. Verificamos como a urgência de geração de conhecimento acelerou, de forma positiva, o debate sobre ética e integridade em pesquisa e ciência aberta. Por outro lado, esse contexto expôs pontos críticos, como práticas questionáveis e/ou fraude em pesquisa. Ações educativas em instituições de pesquisa que visem à implementação e à manutenção da cultura da integridade podem contribuir significativamente para transformações positivas no sistema de pesquisa

During the covid-19 pandemic, a significant increase in the number of publications (articles and preprints) was observed, which led to the rapid sharing of information and encouraged the discussion about scientific integrity in the generation of knowledge during health emergencies. In this sense, the present work aims to analyze research integrity in health publications during the covid-19 pandemic. For this goal, we conducted documentary research on websites of organizations that promote the culture of research integrity. We verified how the urgency of generating knowledge positively accelerated the debate on ethics and integrity in research and open science. On the other hand, this context exposed critical points, such as questionable research practices, and/or research fraud. Educational actions in research institutions aimed at implementing and maintaining a culture of integrity can significantly contribute to positive changes in the research system.

Durante la pandemia de covid-19, se observó un aumento en el número de publicaciones (artículos y preprints), lo que condujo al rápido intercambio de información y fomentó la discusión sobre la integridad científica en la generación de conocimiento durante las emergencias sanitarias. El objetivo de este trabajo fue realizar un análisis sobre la integridad de la investigación en publicaciones de salud durante la pandemia de covid-19. Realizamos una investigación documental en sitios web de organizaciones con trayectoria en la promoción de una cultura de integridad. Comprobamos cómo la urgencia de generar conocimiento aceleró positivamente el debate sobre ética e integridad en la investigación y la ciencia abierta, pero expuso puntos críticos, tales como prácticas cuestionables y/o fraude de investigación. Las acciones educativas en instituciones de investigación dirigidas a implementar y mantener una cultura de integridad pueden contribuir a cambios positivos en el sistema de investigación.

Avaliação de ensaios clínicos no Brasil: histórico e atualidades / Evaluation of clinical trials in Brazil: history and current events / Evaluación de ensayos clínicos en Brasil: historia y actualidad

Resumo Ensaios clínicos devem ser aprovados e acompanhados por autoridades éticas e regulatórias para garantir que a conduta ética e os aspectos técnicos das pesquisas estejam em conformidade com os padrões exigidos. O conhecimento desse processo é primordial para que estudos sejam delineados e conduzidos de acordo com os padrões aplicáveis, sendo parte essencial para a capacitação técnica e científica nacional. No Brasil, a avaliação dos estudos é realizada pelos comitês de ética em pesquisa, pela Comissão Nacional de Ética em Pesquisa e pela Agência Nacional de Vigilância Sanitária. Pesquisadores e patrocinadores alegam que o tempo para aprovação e início de ensaios clínicos limita novos estudos. No entanto, as normas brasileiras estão em contínuo aperfeiçoamento, o que demonstra interesse e capacidade em aprimorar os trâmites, sem perder a qualidade na avaliação ética.

Abstract Clinical trials must be approved and monitored by ethical and regulatory authorities to ensure that the ethical conduct and technical aspects of the research are in compliance with required standards. The in-depth understanding of this process is crucial for studies to be delineated and conducted in accordance with applicable standards, being an essential part of national technical and scientific training. The evaluation of the studies in Brazil is performed by the research ethics committees, by the National Research Ethics Commission and by the Brazilian regulatory agency, the Agência Nacional de Vigilância Sanitária (National Health Surveillance Agency). Researchers and sponsors claim that the time taken for approval and initiation of clinical trials limits further studies. However, Brazilian standards are constantly improving, demonstrating the interest and ability to improve procedures, without losing quality in ethical evaluation.

Resumen Los ensayos clínicos deben ser aprobados y acompañados por autoridades reguladoras y éticas con el fin de garantizar que la conducta ética y los aspectos técnicos de las investigaciones cumplan con los estándares exigidos. El conocimiento de este proceso es fundamental para que los estudios sean delineados y conducidos de acuerdo con los estándares aplicables, siendo una parte esencial para la capacitación técnica y científica nacional. En Brasil, la evaluación de los estudios es realizada por los Comités de Ética en Investigación, la Comisión Nacional de Ética en Investigación y por la agencia reguladora nacional, la Agencia Nacional de Vigilancia Sanitaria. Los investigadores y patrocinadores sostienen que el tiempo para la aprobación y el inicio de ensayos clínicos es un factor limitante para nuevos estudios. No obstante, las normas brasileñas están en continuo perfeccionamiento, lo que demuestra el interés y la capacidad para mejorar los trámites, sin perder calidad en la evaluación ética.

A role for lymphocytes and cytokines on the eosinophil migration induced by LPS

In the present work we review the existing evidence for a LPS-induced cytokine-mediated eosinophil accumulation in a model of acute inflammation. Intrathoracic administration of LPS into rodents (mice, rats and guinea pigs) induces a significant increase in the number of eosinophils recovered from the pleural fluid 24 hr later. This phenomenon is preceded by a neutrophil influx and accompanied by lymphocyte and monocyte accumulation. The eosinophil accumulation induced by LPS is not affected by inhibitors of cyclo or lipoxygenase nor by PAF antagonists but can be blocked by dexamethasone or the protein synthesis inhibitors cycloheximide. Transfer of cell-free pleural wash from LPS injected rats (LPS-PW) to naive recipient animals induces a selective eosinophil accumulation within 24 hr. The eosinophilotactic activity present on the LPS-PW has a molecular weight ranging between 10 and 50 kDa and its effect is abolished by trypsin digestion of the plural wash indicating the proteic nature of this activity. The production of the eosinophilotactic activity depends on the interaction between macrophages and T-lymphacytes and its effect can not be blocked by anti-IL-5 monoclonal antibodies. Accumulated evidence suggest that the eosinophil accumulation induced by LPS is a consequence of a eosinophilotactic cytokine produced through macrophage and T-cell interactions in the site of a LPS-induced inflammatory reaction.