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- Serum calprotectin as a biomarker for diagnosis and monitoring of juvenile idiopathic arthritis - a systematic reviewPublication . Horta, Mariana Pereira; Guerra, Miguel Gomes; Oliveira, Margarida Isabel Dias AlexandreIntroduction: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease in children and is characterized by clinical, pathophysiological, and prognostic heterogeneity. Its etiology remains unclear and, according to the International League of Associations for Rheumatology (ILAR) criteria, encompasses seven distinct subtypes, defined by clinical manifestations. The lack of specific biomarkers hinders early diagnosis, subtype stratification, and monitoring of inflammatory activity, which is often subclinical. Serum calprotectin (sCal), a protein of the calgranulin family produced by activated neutrophils and monocytes, has emerged as a direct marker of synovial inflammation, demonstrating superiority over classic parameters such as C-reactive protein (CRP) and sedimentation rate (ESR). Objective: To carry out a systematic review of the literature, aiming to clarify the role of sCal as a biomarker in the diagnosis and monitoring of JIA, exploring its value in clinical practice and follow-up of these patients. Methods: A systematic search of the PubMed and EMBASE databases was conducted until January 2025, according to the PRISMA 2020 recommendations. Observational studies and clinical trials that analysed sCal in patients with JIA were included, excluding case reports/series, experimental studies in animals, and articles with fewer than 20 participants. Selection was performed by independent reviewers, with discrepancies resolved by consensus. Risk of bias was assessed using tools from the National Heart, Lung, and Blood Institute (NHLB). Data extracted included population characteristics, laboratory parameters, and main outcomes related to diagnosis and monitoring. Results: A total of 639 publications were identified, of which 38 met the inclusion criteria. Overall, sCal levels were significantly higher in children with JIA compared with healthy controls, with better performance in differentiating the systemic form. There was a consistent correlation with clinical activity scores (e.g., JADAS, DAS28), confirming its usefulness in disease monitoring. Several studies have demonstrated the predictive value of sCal in response to different therapies and in predicting relapses after treatment discontinuation. However, the lack of uniform cutoffs and methodological heterogeneity limited comparability between studies. Conclusions: This review confirms the role of sCal as a biomarker with the potential to complement the clinical evaluation of JIA, both in diagnosis and monitoring. The results suggest advantages over traditional markers, particularly in correlation with inflammatory activity and in supporting therapeutic decision-making. However, its integration into routine clinical practice requires validation in robust studies that establish standardized cut-offs and laboratory protocols.
- The Effect of Carbon Nanofibers on the Mechanical Performance of Composite LaminatesPublication . Santos, Paulo Sérgio Pina dos; Reis, Paulo Nobre Balbis dos; Silva, Abílio Manuel Pereira daCarbon fibre reinforced polymer composites are now widely used in various industries/sectors of activity, replacing traditional materials due to their ease of processing, excellent specific resistance, excellent fatigue behaviour, durability and low specific weight. However, the development and optimisation of these materials is faced with new challenges every day, either by optimising their properties or by changing the paradigm in terms of energy consumption. The incorporation of nanofillers significantly improves the mechanical response by reinforcing the polymer matrices and the fibre/matrix interface. This improvement is due to several synergistic mechanisms operating at the nanoscale. In addition, the dispersion of these nanoscale reinforcements within the matrix can inhibit crack propagation and increase the resistance of the material to deformation and fracture. At the fibre/matrix interface, nanofillers can bridge gaps and promote stronger adhesion, resulting in more effective load transfer between the reinforcing fibres and the surrounding polymer. The use of carbon nanofibres (CNFs) offers advantages over other nanofillers such as graphene and carbon nanotubes (CNTs), primarily due to their comparatively lower specific surface area, which facilitates the implementation of accessible and cost-effective manufacturing processes. The lower specific surface area of CNFs, in contrast to the high surface areas of graphene and CNTs, results in reduced interparticle interactions and a lower tendency to agglomerate. In this work, the manufacturing process and the fraction of CNFs that maximises mechanical response, viscoelastic behaviour and impact and fracture resistance were optimised for two commercial epoxy matrices. To assess the improvements, an extensive static mechanical characterisation was carried out, studied the viscoelastic behaviour in bending, interlaminar fracture, low-velocity impact, multiimpact and residual strength and viscoelastic behaviour after impact. The results obtained show that even with small amounts by weight of CNFs (0.5 and 0.75) added to the epoxy resins, significant benefits were obtained, for example: improvements of more than 10% in bending stress and bending stiffness of the matrices and laminates. As a result, the resistance under different strain rates and the interlaminar shear strength were higher in the additive matrices and laminates. In terms of multiple impacts and for an impact energy of 3 J, approximately 66 - 89 impacts are required to achieve full perforation for the nano-enhanced laminate with CNFs, whereas only 17 - 20 impacts are required for the control laminates.
- Impact of radon-rich atmospheres on the growth and development of Mentha spicataPublication . Vicente, Mariana Pinto; Lopes, Lígia Cibele Malavolta de Los Rios; Soares, Sandra da Costa HenriquesThe objective of this work is to investigate the impact of radon-rich (²²²Rn) atmospheres on the growth and development of Mentha spicata L., focussing on the morphological and biochemical changes induced due to exposure to this special gas. This study aims to contribute to the understanding of the environmental impacts of this natural radioactive gas on plants, highlighting the need for continuous research on its toxicity. The findings may have significant implications in elucidating the mechanisms of oxidative stress in plants exposed to radiation. The Mentha spicata, recognised for its medicinal properties, contains phenolic compounds and flavonoids, such as rosmarinic acid and myricetin, which play a significant role in alleviating oxidative stress. For this investigation, the plants were divided into three groups. Group A was exposed to rocks containing uranium, Group B served as the control for Group A, with no exposure to the radioactive atmosphere, and Group C was placed in a laboratory environment without any intervention, which constitutes the control of the experiment. Different analyses were conducted, including the DPPH assay to determine antioxidant capacity and high-performance liquid chromatography (HPLC) to quantify bioactive compounds in a comparative study between exposed and non-exposed plants. Radon exposure reduced the antioxidant capacity and rosmarinic acid content in Mentha spicata compared to the control, indicating an attempt to adapt to radiological stress and inducing measurable changes in the plant’s secondary metabolism. This response promotes the biosynthesis of phenolic compounds with antioxidant activity as a defence mechanism, opening up prospects for potential applications in phytoremediation.