209 research outputs found
Desenvolvimento de uma metodologia de microanálise electromediada (EMMA) para avaliação da actividade de carboxilesterases
O interesse crescente no estudo das carboxilesterases (CES) deve-se ao seu importante papel no metabolismo de fármacos e pró-fármacos, em especial no campo da oncologia. Os métodos convencionais apresentam limitações na avaliação da
actividade específica das diferentes isoformas (CES-1 ou CES-2) em amostras complexas. A microanálise electromediada (EMMA) tem sido utilizada com sucesso em ensaios de actividade enzimática, estudos cinéticos e estudo de inibidores, mas nunca para avaliação de carboxilesterases. Objectivo do estudo: desenvolver uma metodologia de EMMA para avaliar a actividade de CES em amostras biológicas complexas
A tutela indemnizatória dos nascituros já concebidos à luz da dogmática comum da responsabilidade civil
A possibilidade de atribuição de direitos, de variadíssima índole, aos nascituros decorre já do panorama vigente de direito positivo, expondo questões relacionadas com o momento da génese da vida humana, a articulação entre os conceitos de ‘personalidade’ e de ‘capacidade’ jurídica, a própria qualificação conceitual do nascituro enquanto elemento do tráfego jurídico e as implicações legais desse mesmo reconhecimento.
Quando apreciada à luz da responsabilidade civil, a temática, que divide opiniões na doutrina e gera decisões jurisprudenciais contraditórias, ganha renovados contornos, exigindo uma análise cuidada do instituto enquanto expediente adequado para a reparação do dano que possa advir de uma qualquer interação lesiva com o nascituro. Neste estudo, propomo-nos a refletir acerca dos recursos jurídicos de que dispomos para acautelar este estado mais vulnerável do desenvolvimento da pessoa humana, tecendo críticas acerca dos potenciais regimes a aplicar e cogitando sobre soluções desejáveis a adotar, tendo em vista uma proteção abrangente da vida pré-natal.The possibility of granting rights, of various kinds, to unborn children already derives from the prevailing panorama of positive law, exposing questions related to the moment of the genesis of human life, the articulation between the concepts of legal personality and legal capacity, the conceptual qualification of the unborn child as an element of legal interactions and the judicial implications of that same recognition.
When considered in the light of Civil Liability, the theme, which divides opinions in the doctrine and generates contradictory jurisprudential decisions, earns renewed outlines, requiring a careful analysis of the institute as an appropriate remedy for the repair of the damage that may arise from any harmful interaction with the unborn child. In this study, we propose to reflect upon the statutory resources at our disposal to safeguard this most vulnerable condition of human development, criticizing the potential legal frameworks to be applied and considering desirable solutions to be pursued, bearing in mind a comprehensive protection of prenatal life
Bio‐based sensors for smart food packaging—current applications and future trends
Intelligent food packaging is emerging as a novel technology, capable of monitoring the quality and safety of food during its shelf‐life time. This technology makes use of indicators and sensors that are applied in the packaging and that detect changes in physiological variations of the foodstuffs (due to microbial and chemical degradation). These indicators usually provide information, e.g., on the degree of freshness of the product packed, through a color change, which is easily identified, either by the food distributor and the consumer. However, most of the indicators that are currently used are non‐renewable and non‐biodegradable synthetic materials. Because there is an imperative need to improve food packaging sustainability, choice of sensors should also reflect this requirement. Therefore, this work aims to revise the latest information on bio‐based sensors, based on compounds obtained from natural extracts, that can, in association with biopolymers, act as intelligent or smart food packaging. Its application into several perishable foods is summarized. It is clear that bioactive extracts, e.g., anthocyanins, obtained from a variety of sources, including by‐products of the food industry, present a substantial potential to act as bio‐sensors. Yet, there are still some limitations that need to be surpassed before this technology reaches a mature commercial stage.publishersversionpublishe
Chemical Composition of the Essential Oils in Portuguese Daucus Carota Subspecies
This study focused on five different subspecies of Portuguese Daucus carota L., to identify the main compounds in the essential oils of umbels from each subspecies. The isolation of the essential oils was performed by hydrodistillation methods followed by further composition analysis by gas chromatography-mass spectrometry, ultimately demonstrating that each subspecies had different major compounds. This study concluded that the main compounds found in Daucus carota subsp. maritimus were geranyl acetate, followed by trans-methyl-isoeugenol, α-pinene, cis-asarone and elemicin. Daucus carota subsp. hispidus presented with the major compounds as geranyl acetate, caryophyllene oxide, trans-methyl-isoeugenol and sabinene. For Daucus carota subsp. maximus, the major compounds were cis-asarone, geranyl acetate and elemicin, which was similar to Daucus carota subsp. carota which presented with the major compounds as geranyl acetate, cis-asarone, trans-methylisoeugenol and α-pinene. Finally, the major components of Daucus carota subsp. sativus were carotol and daucol.
Keywords: essential oils, chemical composition, Daucus carota, hydrodistillation, GC-M
Sapwood of carob tree (Ceratonia siliqua L.) as a potential source of bioactive compounds
Methanol (ME) and hot water extracts (WE) of carob tree sapwood (Ceratonia siliqua L.) exhibited high antioxidant activity and were rich in phenolic compounds, with the main compounds identified by HPLC/DAD as gentisic acid and (-)-epicatechin. The ME displayed a high in vitro antitumor activity against human tumoural cell lines and reduced intracellular ROS production by HeLa cells after treatment with H2O2. (-)-Epicatechin was shown to contribute to the cytotoxic activity of the ME. This is the first report on the biological activity of carob tree sapwood
Extraction Improvement and Chemometric Study
Funding Information: This work was supported by the NoAW project (‘‘Innovative approaches to turn agricultural waste into ecological and economic assets”), founded by the European Union Horizon 2020 research and innovation program under the grant agreement No 688338. This research was carried out within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR)–MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4–D.D. 1032 17/06/2022, CN00000022), Italy. This study was also funded by national funding by FCT, Foundation for Science and Technology, MCTES, and by ESF (European Social Fund) through NORTE 2020 (Programa Operacional Região Norte), Portugal, through the individual PhD research grant (SFRH/BD/146080/2019) of V.L. This work was also supported by the MEtRICs unit which is funded by national funds from FCT/MCTES (UIDB/04077/2020 and UIDP/04077/2020) and by the Associate Laboratory for Green Chemistry–LAQV which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020). Publisher Copyright: © 2023 by the authors.In the last 20 years, an increased interest has been shown in the application of different types and combinations of enzymes to obtain phenolic extracts from grape pomace in order to maximize its valorization. Within this framework, the present study aims at improving the recovery of phenolic compounds from Merlot and Garganega pomace and at contributing to the scientific background of enzyme-assisted extraction. Five commercial cellulolytic enzymes were tested in different conditions. Phenolic compound extraction yields were analyzed via a Design of Experiments (DoE) methodology and a second extraction step with acetone was sequentially added. According to DoE, 2% w/w enzyme/substrate ratio was more effective than 1%, allowing a higher total phenol recovery, while the effect of incubation time (2 or 4 h) variation was more enzyme-dependent. Extracts were characterized via spectrophotometric and HPLC-DAD analyses. The results proved that enzymatic and acetone Merlot and Garganega pomace extracts were complex mixtures of compounds. The use of different cellulolytic enzymes led to different extract compositions, as demonstrated using PCA models. The enzyme effects were observed both in water enzymatic and in the subsequent acetone extracts, probably due to their specific grape cell wall degradation and leading to the recovery of different molecule arrays.publishersversionpublishe
A Bioética Cotidiana como instrumento de reflexão sobre a atenção à saúde da população LGBT
The discrimination based on sexual orientation and gender identity in the social determination of the disease makes the issue of health care for the LGBT population (Lesbian, Gay, Bisexual, Transvestite and Transsexual) a question of ethics. Recognizing the Everyday Bioethics proposed by Giovanni Berlinguer as a powerful reference for the analysis of ethical problems, it is proposed an approximation between the health care of the LGBT population as object of analysis and the referred theoretical reference. For this reason, some concepts that allow us to highlight the morality implied in gender phobias, notably heteronormativity, homophobia and cisnormativity, are presented, in order to later draw the possible approximations between Everyday Bioethics and the health care problem of the LGBT population. It was considered that Everyday Bioethics constitutes a reflective apparatus of deep critical analysis to the way in which the health and life issues as a whole are treated, being able to include in its agenda the situations linked to the issues of gender, discrimination and social exclusion.A discriminação por orientação sexual e por identidade de gênero na determinação social da doença faz com que a problemática da atenção à saúde da população LGBT (Lésbicas, Gays, Bissexuais, Travestis e Transexuais) possa ser percebida também como uma questão de ordem ética. Reconhecendo a Bioética Cotidiana proposta por Giovanni Berlinguer enquanto potente referencial de análise de problemas éticos, propõe-se uma aproximação entre a atenção à saúde da população LGBT enquanto objeto de análise e o referido referencial teórico. Neste sentido, abordam-se inicialmente alguns conceitos que permitem evidenciar a moralidade implicada nas fobias de gênero, notadamente heteronormatividade, homofobia e cisnormatividade, para posteriormente traçar as aproximações possíveis entre a Bioética Cotidiana e a problemática da atenção à saúde da população LGBT. Considerou-se que a Bioética Cotidiana constitui um aparato reflexivo de profunda análise crítica à maneira como as questões de saúde e de vida como um todo são tratadas, podendo-se então incluir em sua pauta as situações atreladas à s questões de gênero, discriminação e exclusão social
Pozzolanic activity of metakaolins by the French standard of the modified Chapelle test: A direct methology
This research was focused on the use of the modified Chapelle test as a direct laboratory methodology to access the pozzolanic activity of both experimental and commercial metakaolins. At the same time, this test was used in the evaluation of experimental metakaolins. This chemical test, performed during 16 hours at 90 °C, allows the quantification of portlandite fixed by the metakaolin sample. The calcium hydroxide that was not consumed is quantified by acid titration (HCl), and the test result is expressed in mg of fixed calcium hydroxide by g of metakaolin. According to this test, the pozzolanic activity of a metakaolin should not be less than 700 mg Ca(OH)2 / g metakaolin. The modified Chapelle pozzolanic activity of six commercial metakaolins was evaluated between 920 and 1560 mg Ca(OH)2 / g metakaolin. From the seven experimental metakaolins produced between 750 ºC and 940 ºC, a material with modified Chapelle pozzolanic activity value of 1240 mg Ca(OH)2 / g metakaolin was obtained, which is similar to some tested commercial metakaolins produced at industrial scale. The metakaolin produced at 800 ºC was ground, resulting in a particle size reduction of ≈ 4x less and a consequent increase of 21% in the pozzolanic activity.This research was supported by Sistema de Incentivos à Investigação e Desenvolvimento Tecnológico - Vale I&DT to Cerâmica Condestável, Lda (Portugal), supported by Quadro de Referência Estratégica Nacional, Rese arch Project METACAL - Study of Lime-Metakaolin Mortars for Building Conservation (PTDC/ECM/100431/2008), Research Unit (UID/GEO/04035/2013) and Projecto Estratégico (PEst-OE/CTE/UI4035/2014) financed by the Fundação para a Ciência e a Tecnologia (FCT) and COMPETE - Programa Operacional Factores de Competitividade.info:eu-repo/semantics/publishedVersio
In vitro cytotoxic effects and apoptosis induction by a methanol leaf extract of carob tree (Ceratonia siliqua L.)
This research evaluated the in vitro apoptotic inducing properties of a methanol leaf extract of carob tree (Ceratonia siliqua L.) on a human cervical adenocarcinoma cell line (HeLa). The cell viability effect on a prostate (DU-145), breast (MDA-MB-231) and colon cell line (HCT-166) was also assessed. The effect of the extract on reactive oxygen species (ROS) production by HeLa cells was studied, and a phytochemical evaluation was made by high performance liquid chromatography with diode array detection (HPLC). Total mean yield of identified phenols was 261.1 mg/g DW, and (+)-catechin was the major compound (76.8 mg/g DW). The extract decreased cell viability in a dose-and time-dependent manner, and a more pronounced effect on HeLa line was observed. In vitro cytotoxic activity was associated with apoptosis, but not to the increase of ROS production. Among the tested compounds identified in the extract, the highest activity was detected with gallic acid (GA), (+)-catechin and quercetin, with reductions in HeLa cells viability down to 8.0, 11.9 and 27.1%, respectively. This is the first report on the apoptotic activity of a leaf extract of carob tree on a human cancer cell line, suggesting that it may be a potential source of chemopreventive compounds
Hepatic immune-mediatedadverseeffects of immune checkpoint inhibitors: analysis of real-life experience
Introduction and objectives: Immune Checkpoint Inhibitors (ICI) have shifted the paradigm of cancer therapy treatment. Despite their efficacy, ICIs may induce immune-related adverse events (irAE), which can affect various organs, namely the liver. This study intends to perform a comprehensive clinical description of the hepatic irAEs associated with ICI in a Portuguese population of a tertiary hospital centre.
Materials and methods: A retrospective analysis of patients who developed immune-mediated liver injury (IMLI), among a cohort of patients treated with ICIs between March 15th of 2015 and December 15th of 2019 in a tertiary hospital. We used both Common Terminology Criteria for Adverse Events (CTCAE) and Drug-Induced Liver Injury Network (DILIN) criteria to define liver injury.
Results: Among 151 patients, eight (5.3%) patients developed liver injury grade ≥3, of which five had hepatic metastasis. As such, only 3 cases were classified as IMLI. All IMLI presented with cholestasis pattern; the median duration from ICI initiation to IMLI was 84 days and/or 4 ICI cycles; one patient registered IMLI one month after nivolumab suspension; all were treated with steroids and one was successfully submitted to ICI re-challenge; a favourable outcome was seen in all patients; the median time to hepatic biochemistries normalization was 150 days. Among 10 patients with previous hepatic conditions, only one developed liver injury grade 2.
Conclusions: Clinically significant ICI-related hepatotoxicity was uncommon; Immune-mediated liver injury may present a cholestatic pattern predominance. There was a low rate of liver injury of any kind in patients with previous hepatic disease while on ICI.info:eu-repo/semantics/publishedVersio
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