Percorrer por autor "Fernandes, Sílvia"
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- Acetyl-L-Carnitine Improves Cell BioenergeticsPublication . Cunha, Lídia; Bravo, Joana; Costa, Pedro; Fernandes, Sílvia; Oliveira, Marta; Castro, Rosa; Metello, Luís F.; Summavielle, TeresaIntroduction: Acetyl-L-Carnitine (ALC), a natural occurring compound in all mammalian species, plays a variety of vital functions in the body. The most important are related to mitochondria, namely the transport of fatty acids for energy production through β oxidation and the control of acyl-CoA/CoA ratio. Due to this close interaction with cell bioenergetics, it plays a role in many diseases, especially those related to the mitochondria. We propose to characterize the action of ALC in mitochondrial bioenergetics and functional integrity.
- ALC Neuroprotection through autophagy and ups acitivityPublication . Bravo, Joana; Cunha, Lídia; Fernandes, Sílvia; Binienda, Zbigniew; Summavielle, TeresaAcetyl–L-carnitine (ALC) has beneficial effects in neurodegenerative diseases and was shown to be protective against exposure to methamphetamine (METH) reducing mitochondrial dysfunction and oxidative stress. However, the mechanisms underlying ALC action are still unknown, limiting its putative therapeutic use.
- Betulinic acid and obesity-related disordersPublication . Azevedo, Lara; Ferraz, Ricardo; Vieira, Mónica; Prudêncio, Cristina; Fernandes, Sílvia; Ferraz, Ricardo; Almeida Vieira, Mónica Andreia; Prudêncio, Cristina; Fernandes, SílviaThe obesity epidemic is not just a health issue, it is increasingly driving a shift in the prevalence of chronic diseases, affecting 890 million adults and straining healthcare systems worldwide. Conditions such as type 2 diabetes mellitus, cardiovascular diseases, non-alcoholic fatty liver disease, and various cancer types are closely tied to this growing crisis. Betulinic acid has anti-inflammatory, antioxidant and anti-cancer properties and modulates key metabolic pathways such as NF-κB and AMPK signaling. This compound improves insulin sensitivity, reduces hepatic steatosis, mitigates the progression of atherosclerosis and fibrosis, and suppresses inflammatory responses, which are important in treating those obesity-related disorders. Additionally, betulinic acid use in cancer treatment has been explored due to its potential in angiogenesis and metastasis inhibition and promotion of apoptosis. This review spotlights the therapeutic potential of the natural compound betulinic acid in processes such as insulin sensitivity, glucose and lipid metabolism, adiposity, inflammation, oxidative stress, intestinal microbiota, and other mechanisms underlying different obesity-related disorders. Overall, besides strong therapeutic potential of betulinic acid, described limitations such as poor aqueous solubility, limited bioavailability, production and extraction have resulted in scarce clinical data making it premature to draw definitive conclusions regarding its application in clinical practice.
- Betulinic acid for glioblastoma treatment: Reality, challenges and perspectivesPublication . Fernandes, Sílvia; Vieira, Mariana; Prudêncio, Cristina; Ferraz, RicardoBetulinic acid is a naturally occurring compound that can be obtained through methanolic or ethanolic extraction from plant sources, as well as through chemical synthesis or microbial biotransformation. Betulinic acid has been investigated for its potential therapeutic properties, and exhibits anti-inflammatory, antiviral, antimalarial, and antioxidant activities. Notably, its ability to cross the blood–brain barrier addresses a significant challenge in treating neurological pathologies. This review aims to compile information about the impact of betulinic acid as an antitumor agent, particularly in the context of glioblastoma. Importantly, betulinic acid demonstrates selective antitumor activity against glioblastoma cells by inhibiting proliferation and inducing apoptosis, consistent with observations in other cancer types. Compelling evidence published highlights the acid’s therapeutic action in suppressing the Akt/NFκB-p65 signaling cascade and enhancing the cytotoxic effects of the chemotherapeutic agent temozolomide. Interesting findings with betulinic acid also suggest a focus on researching the reduction of glioblastoma’s invasiveness and aggressiveness profile. This involves modulation of extracellular matrix components, remodeling of the cytoskeleton, and secretion of proteolytic proteins. Drawing from a comprehensive review, we conclude that betulinic acid formulations as nanoparticles and/or ionic liquids are promising drug delivery approaches with the potential for translation into clinical applications for the treatment and management of glioblastoma.
- Betulinic acid modulates adipocyte differentiation and secretome activity: Downstream effects on Glioblastoma cell migrationPublication . Gouveia, Afonso; Ferraz, Ricardo; Prudêncio, Cristina; Fernandes, Silvia; Fernandes, SílviaBetulinic acid (BA) has been recognized for its po-tential to modulate tumor progression and adipocyte function, yet its effects on adipocyte secretome re-modeling and the downstream consequences for glio-blastoma behavior remain incompletely understood1-4. In this study, we investigated the influence of BA on adipocyte secretory activity and its functional impact on glioblastoma cell migration. Direct exposure of U251 glioblastoma cells to BA significantly reduced cell migration, confirming its intrinsic anti-migratory potential. To further explore microenvironmental in-teractions, adipocyte-conditioned media (ACM) de-rived from BA-treated adipocytes was evaluated for its effects on glioblastoma behavior. Secretome anal-ysis demonstrated that BA altered matrix metallopro-teinase (MMP) expression and reduced gelatinolytic activity, indicating significant modulation of extracel-lular matrix–related proteolytic pathways. Functional assessment using wound healing assays revealed that ACM from BA-treated adipocytes did not consistent-ly suppress glioblastoma migration. Intermediate BA concentrations were associated with increased migratory behavior relative to basal conditions, although differences compared with control ACM were not statistically significant. Additionally, transwell migra-tion assays did not demonstrate significant differ-ences between treatment conditions, suggesting that BA-induced alterations in adipocyte secretome com-position do not uniformly translate into measurable changes in glioblastoma migratory capacity across dif-ferent experimental models. These findings indicate that modulation of gelatinolytic pathways alone is insufficient to predict glioblastoma cell migration and support the contribution of additional adipocyte-de-rived signalling mechanisms in regulating tumor be-havior. Overall, BA induces substantial remodelling of adipocyte secretory function, producing complex and non-linear downstream effects on glioblastoma cells. This study highlights the importance of tumor micro-environment crosstalk and underscores the need to evaluate multiple regulatory pathways when consid-ering the therapeutic potential of BA and related bio-active compounds.
- Chlorella vulgaris (SAG 211-12) biofilm formation capacity and proposal of a rotating flat plate photobioreactor for more sustainable biomass productionPublication . Melo, Miguel; Fernandes, Sílvia; Caetano, Nídia; Borges, Maria TeresaDifficulties and cost of suspended microalgal biomass harvest and processing can be overcome by cultivating microalgae as biofilms. In the present work, a new photoautotrophic biofilm photobioreactor, the rotating flat plate photobioreactor (RFPPB), was developed aiming at a cost-effective production of Chlorella vulgaris (SAG 211-12), a strain not frequently referred in the literature but promising for biofuel production. Protocols were developed for evaluating initial adhesion to different materials and testing the conditions for biofilm formation. Polyvinyl chloride substrate promoted higher adhesion and biofilm production, followed by polypropylene, polyethylene, and stainless steel. The new RFPPB was tested, aiming at optimizing incident light utilization, minimizing footprint area and simplifying biomass harvesting. Tests show that the photobioreactor is robust, promotes biofilm development, and has simple operation, small footprint, and easy biomass harvest. Biomass production (dry weight) under non-optimized conditions was 3.35 g m−2, and areal productivity was 2.99 g m−2 day−1. Lipid content was 10.3% (dw), with high PUFA content. These results are promising and can be improved by optimizing some operational parameters, together with evaluation of long-term photobioreactor maximum productivity.
- Cuidar ao cuidar - Estratégias e ferramentas para promover a saúde mental e emocional dos cuidadores.Publication . Fernandes, Sílvia; Portugal, Paula; Silva, Regina A.O Family Caregiver Support - Strategies and Tools to Promote Caregivers’ Mental and Emotional Health é um projeto financiado pelo Programa Erasmus+ ação-chave 2-parcerias estratégicas para educação de adultos, e conta com a colaboração de vários países da União Europeia como parceiros-membro. A necessidade deste projeto surge do levantamento de necessidades efetuado a nível europeu, que revela que há uma sobrecarga muito grande dos cuidadores familiares de indivíduos com doença mental grave: estes gastam em média 6 a 9 horas por dia na prestação de cuidados e, em mais de um terço dos casos, são os únicos cuidadores desse paciente. Apesar do seu papel primordial, os cuidadores sentem o seu trabalho desvalorizado pelos sistemas de saúde e políticos, para além de colocarem em risco a sua saúde física, mental e emocional. Este projeto surge com o objetivo de capacitar os cuidadores informais para desenvolverem autoconfiança e competências no desempenho das suas funções. Para o efeito, irão ser desenvolvidos um conjunto de recursos on-line contemplando conteúdos relevantes para a formação e informação no âmbito da literacia em saúde mental e de ferramentas úteis que os capacitem a cuidar de si ao cuidar dos outros. Estes recursos irão ser disponibilizados de uma forma interativa numa plataforma online e através de uma aplicação móvel. Desta forma, este projeto assenta num pilar base para a educação de adultos no âmbito da promoção da saúde, física, mental e emocional do cuidador.
- CytoPath®Easy processing method validation through cervical self-samplingPublication . Fernandes, Sílvia; Martins, C.; Silva, ReginaLiquid-based cytology is mostly used for the identification of pre-neoplastic and neoplastic cells of cérvix uteri, and many manual and automatic methodologies are available on the market. This study aims to validate a new manual liquid-based processing method - the CytoPath® Easy Kit, for its routine use in some cytology laboratories.
- CytoPath®Easy: screening of cervical cancerPublication . Fernandes, Sílvia; Vilarinho, Ana Sofia; Silva, ReginaRecently, CytoPath®Easy kit was created by DiaPath S.p.A. and started to be commercially available for the screening of cervical cancer. Using this methodology, epithelial cells are immersed in a preservative liquid, and a thin-layer of cells in the slide is obtained through gravity sedimentation and filtration. The main objectives of this study are to evaluate the efficacy for the processing of cervical samples, for the detection of pre-neoplastic lesions and for the nucleic preservation and extraction by the kit. For this purpose, 215 cervical samples obtained by self-sampling were used: 174 were collected and processed by CytoPath® Easy and, as a control, 41 were collected and processed by the Thinprep® method. The samples were processed, stained by the Papanicolaou method, and independently evaluated microscopically for various morphological parameters; nucleic acids were isolated and evaluated for purity and integrity by spectrophotometry. Results obtained showed that both methods have a good performance, allowing the morphological evaluation of the cervical epithelium. However, the statistical analysis reveals that the methods are different from each other, with overall lower results being obtained in the method under study (p<0.001). In turn, both methods allow the extraction of good quality and quantity of DNA. Although some differences were found regarding morphology of the cells fixed and processed by the CytoPath®Easy method, this new methodology reveals efficient for the preservation of nucleic acids. Thus, its use in cervical cancer screening is recommended.
- CytoScope – Ferramentas digitais no Ensino SuperiorPublication . Fernandes, Sílvia; Mota, Catarina; Silva, Regina; Silva, Regina; Fernandes, SílviaA patologia digital tem um impacto significativo no ensino em saúde. Na área da citopatologia, as ferramentas digitais permitem o acesso remoto a casos clínicos, ultrapassando a necessidade física quer das lâminas, quer do microscópio. Dada a complexidade da citopatologia não ginecológica e a falta de ferramentas adequadas para o estudo autónomo, a modernização das ferramentas pedagógicas continua a ser uma necessidade. Em 2015, a Escola Superior de Saúde do Politécnico do Porto implementou, de forma pioneira, uma laminoteca digital no âmbito do ensino em citologia ginecológica. Esta ferramenta foi de enorme utilidade no período da pandemia e é utilizada anualmente como complemento ao estudo microscópico no âmbito da licenciatura em Ciências Biomédicas Laboratoriais. Um inquérito aos estudantes 3º e 4º ano do curso acerca da laminoteca aferiu uma elevada taxa de utilização e de satisfação, e a maioria dos estudantes reconhece que a ferramenta promoveu um melhor desempenho académico. Os estudantes que não a utilizaram destacam o desconhecimento da sua existência ou dificuldades na configuração como principais motivos. Estas lacunas foram tidas em consideração para a construção de uma laminoteca de citologia não ginecológica otimizada. Foi desenvolvido o Non-Gyn CytoScope, que inclui vídeos com instruções de instalação e de uso, uma interface intuitiva e um maior número de casos clínicos disponíveis para estudo, com organização em categorias diagnósticas. No total, o catálogo da laminoteca inclui 300 casos de citologia dos vários sistemas do organismo, digitalizados a 40x através de Whole Slide Imaging. As imagens são disponibilizadas numa plataforma em HTML e visualizadas no software CaseViewer, permitindo o acesso a partir de um dispositivo móvel a qualquer hora e em qualquer lugar. A aplicação das ferramentas digitais permite aos estudantes um complemento ao estudo fora da sala de aula e do laboratório, promovendo uma aprendizagem centrada e gerida pelo estudante.
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