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- Characterization and evaluation of joint properties of friction stir welded AA7075/GNPs joints obtained using square and cylindrical threaded toolsPublication . Fernandes, Filipe; Biradar, Rahul; Patil, Sachinkumar; Nagamadhu, M.; Sharma, PriyaranjanThis study investigates the joint properties and microstructural features of friction stir-welded (FSWed) AA7075 aluminum alloy composites reinforced with 1 wt % of graphene nanoplatelets (GNPs). It focuses on the influence of square (SQ) and cylindrical threaded (CT) tool pin geometries on material flow, GNPs dispersion, and weld quality. The authors conducted comprehensive evaluations using advanced characterization methods including scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and Raman spectroscopy. The results reveal formation of precipitates and well bonding between aluminum alloy and GNPs, resulting in better quality of welds. The SQ tool facilitated superior material stirring and uniform dispersion of GNPs, leading to the formation of fine, equiaxed grains in the nugget zone (NZ). Electron back scatter diffraction (EBSD) analysis presents reduction of grain size of base material from 38 μm to 10 μm in the NZ, significantly enhancing mechanical properties. Welds produced using the SQ tool exhibited higher microhardness (150 HV) and tensile strength (630 MPa) compared to those made with the CT tool (141 HV and 478 MPa), resulting in a 75 % improvement in joint efficiency. Fracture analysis revealed ductile failure in the heat-affected zone (HAZ), with fine dimples observed in SEM images. Additionally, the SQ tool weld demonstrated a lower wear rate, reduced from 70 μm to 25 μm, than its counterpart. These findings highlight the importance of tool geometry in producing defect-free, high-performance welds.
- Tribological performance of different alloyed DLC and AlTiSiN coatings when sliding against Inconel 718 alloy for demanding applicationsPublication . Fernandes, Filipe; Pérez-Salinas, Cristian; Evaristo, Manuel; Cavaleiro, Albano; Kumar, Ch. Sateesh; Lacalle, L. Norberto López; Rios, P.Machining Ni alloys such as Inconel 718 is challenging due to its good mechanical properties, low thermal conductivity and low elastic modulus, which causes high cutting temperatures at the chip-tool interface. The use of self-lubricating coatings, such as DLCs coatings has potential to improve significantly the machinability of Ni alloys. This research work aims to explore how different DLC, DLC-Si, DLC-W coatings behave tribologically when sliding against Inconel 718. The results will be compared with an industrial AlTiSiN coating used to protect the cutting tools. The morphology, mechanical properties and chemical composition of the coatings were analysed. To evaluate the tribological behaviour alternative sliding tests were performed under different conditions (room temperature – RT and 200 °C in dry condition and at RT with lubrication, using CUT-MAX S 50259-1 oil. The DLC coatings showed remarkable self-lubricating efficiency, with low coefficients of friction even in dry conditions, demonstrating that their self-lubricating capability is effective without the need for external lubricants. However, at a temperature of 200 °C, a significant increase in wear rate was observed for all DLC coatings, being 3 to 4 times higher as compared to that at room temperature. This is mainly caused by the conversion of sp3 to sp2 bonds coating oxidation. On the other hand, AlTiSiN demonstrated consistent specific wear rate, despite of the unfavourable circumstances, highlighting its suitability to use in extreme environments. These results show the limitations in film performance and underline the importance of balancing the strength of the coating with its impact on the opposing surface. Furthermore, it highlights the need to improve the thermal stability of DLC coatings for application in high temperature environments and dry conditions.
- Multidose drug dispensing systems: a focus on user experiences, safety, quality and cost factorsPublication . Reis, Ana; Pereira, Jorge; Iacob, Andrei; Filipoi, Victoria-Adriana; Martin, Maria Luisa; Jesus, Ângelo; Jesus, ÂngeloPopulation aging is one of the most significant social transformations of the 21st century, especially in developed countries. Medication-related behaviour is complex and influenced by multiple factors, requiring diverse strategies to improve adherence. In this context, pharmacists and pharmacy technicians have taken on increasingly important roles in promoting and providing health services. Pharmacy technicians, in particular, can contribute significantly to the implementation of community adherence programs. Individualized medication preparation, such as multiple dose dispensing (MDD) systems, offers an approach that ensures patients receive the correct medication, in the correct dose and at the correct time, improving safety and adherence, particularly among older adults. The study involves identifying current evidence on the implementation and use of MDD systems and exploring possible improvements, particularly for older populations. This assessment analysis follows the Joanna Briggs Institute methodology. The protocol was developed with predefined criteria appropriate for the selected databases and repositories. Article selection, data extraction, and synthesis were performed independently by two reviewers to ensure rigor. In conclusion, MDD systems represent a promising intervention to support medication adherence, tailored to the individual needs of each patient.
- Early-life exposure to non-nutritive sweeteners: Impact on adipose tissue morphology and metabolic functionPublication . Oliveira-Barbosa, Margarida; Bracchi, Isabella; Keating, Elisa; Negrão, RitaNon-sugar sweeteners (NSS) are sugar alternatives widely incorporated into food and beverages (1), providing sweetness with negligible caloric contribution (2). Over the past two decades, their consumption has increased among pregnant women (3,4). In 2023, WHO discouraged NSS intake highlighting the need for studies regarding exposure during critical windows of development (5), such as pregnancy and childhood (6). The MHSWEET project explores the role of NSS consumption on fetal programming of metabolic dysfunction. This branch of the MHSWEET aims to evaluate metabolic function of adipose tissue of adult mice exposed in utero to Rebaudioside A (RebA), the main sweetener component of the NSS Stevia. It also seeks to determine if this early-life exposure affects offspring’s susceptibility to metabolic dysfunction induced by a high-fat diet (HFD). Female Sprague-Dawley rats (G0) ingested RebA in drinking water (4mg steviol eq/kg body weight/day – EFSA’s ADI, n=8), or regular water (C, n=8), before mating until weaning (13 weeks). After weaning, offspring (G1) were fed a standard diet (STD) until 8 months of age, when they were administered STD or HFD until 10 months of age, creating 4 groups of study: C/STD, C/HFD, RebA/STD and RebA/HFD. Mesenteric adipose tissue morphology (H&E staining), as well as lipid and mitochondrial metabolic pathways (RT-PCR) will be assessed. The results so far showed that RebA exposure increased body weight in female offspring from 30 weeks of age onwards compared to controls (p=0.0165). Blind histological and RT-PCR analyses are ongoing to search for: a) adipocyte hypertrophy potentially induced by RebA exposure or HFD, mainly in RebA exposed offspring and b) alterations in lipid and mitochondrial metabolic pathways that may explain the observed changes in body weight and any changes in adipocyte morphology. This study will be crucial to assess health implications of NSS consumption during vulnerable stages of life.
- Development of an in vitro skin cell model and comparison with ex vivo models: the case study of green cosmetic active ingredientsPublication . Marques, Mariana; Teixeira, Filipa; Vieira, Mónica; Rodrigues, Francisca; Vieira, MónicaSkin is the first physical barrier against pathogens and mechanical injuries, and stratum corneum, the outermost layer of the skin, is the primary barrier to therapeutic delivery. Skin is divided into the epidermis, which consists mainly of keratinocytes and the dermis, composed of fibroblasts, and extracellular matrix components. Skin models are crucial for assessing the safety and efficacy of cosmetic ingredients, especially under European Regulation (CE) No. 1223/2009 that bans animal testing in cosmetics [1]. While commercial skin models approved by the Organization for Economic Co-operation and Development (OECD) exist, they often lack physiological complexity, limiting their relevance for regulatory compliance [2]. With this work, we aim to develop and characterize a 3D in vitro skin model to evaluate the effect of green cosmetic active ingredients—catechin, epicatechin, chlorogenic acid, and neochlorogenic – due to their antioxidant and anti-aging properties. A keratinocyte (HaCaT)-fibroblast (HDF) coculture and a hydrogel matrix were established to mimic native skin properties, with TEER measurements assessing barrier integrity and MTT assays evaluating cytotoxicity and viability. Permeability studies, performed using Franz cells and HPLC-MS analysis, compared compound penetration in the developed 3D model, ex vivo skin explants, and the commercial EpiSkinTM model. Preliminary results indicate that the developed 3D in vitro skin model successfully supports keratinocyte-fibroblast co-culture, with TEER values suggesting the establishment of a functional barrier. The development of a physiologically relevant 3D in vitro skin model represents a significant step toward improving in vitro testing of green cosmetic active ingredients. This work is an advancement on sustainable and ethical cosmetic testing, bridging the gap between traditional models and human physiology.
- Decoding host-environment interactions in progressive pulmonary fibrosis: insights from hypersensitivity pneumonitisPublication . Meneses, Alexandra; Cardoso, Catarina G.; Coelho, David B.; Melo, Natália; Mota, Patrícia C.; Guimarães, Susana; Moura, Conceição S.; Carvalho, André; Sokhatska, Oksana; Beltrão, Marília; Delgado, Luís; Morais, António; Saraiva, Margarida; Bastos, Hélder N.; Santos, Rita F.Interstitial lung diseases (ILDs) comprise a heterogeneous group of parenchymal lung disorders characterized by diffuse infiltration of immune effector cells, fibroblasts, myofibroblasts, and extracellular matrix deposition at various pulmonary compartments. These conditions can progress to end-stage fibrosis, respiratory failure, and eventually, death. In 2020, we initiated the first national ILD registry and biobank under the FIBRALUNG project, which has enrolled over 950 cases to date, with over 40% of the cases being fibrotic ILDs. The most represented fibrotic ILD groups are Hypersensitivity Pneumonitis (HP) (46%), Idiopathic Pulmonary Fibrosis (IPF) (20%), and unclassifiable ILD (8%). HP is the leading cause of pulmonary fibrosis, nearly doubling the number of IPF cases, which contrasts with numbers from other countries. This underscores the importance of investigating non-IPF progressive pulmonary fibrosis within our setting. Longitudinal patient follow-up and biological sample collection were performed allowing patient stratification according to progression criteria. Our work so far has highlighted a potential role of CCL2-CCR2 axis in fibrotic HP disease progression. Elevated serum CCL2 strongly associated with disease progression and acute exacerbations, with baseline levels above 1080 pg/mL predicting oneyear progression/mortality. To complement these findings, we are conducting blood transcriptome analyses across different HP patient groups to identify progression-specific signatures. Simultaneously, lung microbiome profiling is underway to explore its role in fibrotic progression. These integrative approaches aim to uncover novel biomarkers and mechanistic pathways, paving the way for tailored therapeutic interventions.
- Copine 1 counteracts pneumolysin-induced plasma membrane damage caused by Streptococcus pneumoniae infectionPublication . Monteiro, João; Lima, Ricardo; Vale-Costa, Sílvia; Sousa, SandraStreptococcus pneumoniae causes pneumonia, meningitis, and sepsis, leading to millions of hospitalizations and deaths annually despite vaccination efforts. Understanding bacterial interaction with host cells is key to developing innovative therapies. Pneumolysin (PLY), a S. pneumoniae virulence factor, forms pores in the host cell plasma membrane (PM) to disrupt cellular integrity and promote bacterial dissemination. Host cells rely on repair mechanisms to counteract PM damage induced by PLY(1). We recently identified Copine 1, a calcium-dependent phospholipid-binding protein, as a key player in this repair process(2) However, its precise role in PM repair remains unclear, which is the focus of this study. To ascertain if Copine 1 redistributed to PM damage sites, A549 (lung epithelial) or HeLa (cervix epithelial) cells were treated with purified PLY, infected with S. pneumoniae, or untreated. Protein localization was assessed by immunofluorescence confocal microscopy. To identify Copine 1 partners involved in PM repair, HEK 293T (kidney epithelial) cells expressing Copine 1 fused to a biotin ligase were non-intoxicated or intoxicated with PLY in the presence of exogenous biotin. Biotinylated proteins were purified and identified by mass-spectrometry. Following both PLY intoxication and bacterial infection, Copine 1 was recruited to nonmuscle myosin heavy chain IIA protein accumulations at the PM, which are PM sites associated with effective repair upon damage by other bacterial pore forming toxins (3,4). The results from the mass-spectrometry analysis are pending. These findings suggest, thus far, that Copine 1 counteracts PLY-mediated PM damage by participating in cortical actomyosin cytoskeleton remodeling.
- Dissecting the sensory defects of bbs mutants in Caenorhabditis elegansPublication . Vitória, Filipa; Rocha, Sónia; Rocha, Helder; Abreu, Carla M. C.; Dantas, Tiago J.Ciliopathies encompass a group of genetic disorders affecting multiple organs due to dysfunction in cilia: highly conserved organelles found in most human cells. Bardet-Biedl Syndrome (BBS) is a rare ciliopathy characterized by multisystem abnormalities. BBS arises from defects in assembly, composition, or localization of the BBSome, a conserved eight-subunit protein complex crucial in ciliary transport. Sensory neurons rely on cilia to detect environmental stimuli and transduce signals essential for perception. In BBS, defective cilia function disrupts these processes, leading to impaired sensory responses. Despite advances in BBS genetics, the role of ciliary defects in sensory neuron dysfunction remains unclear. To address this gap, we utilize Caenorhabditis elegans as a model organism to dissect the sensory impairments associated with BBS mutations. Unlike mammalian systems, C. elegans can survive severe ciliary dysfunction, making it ideal for studying BBS mutations. We analyzed bbs-1 mutants to investigate sensory defects in ciliated neurons, conducting behavioral assays to assess responses to environmental stimuli, and dye-filling assay to evaluate ciliary integrity. Preliminary findings indicate disruptions in sensory neuron function, correlating with defects in ciliary morphology. Additionally, defective dye uptake in bbs-1 mutants suggests compromised ciliary integrity. Our findings emphasize the importance of ciliary function in sensory processing in C. elegans, reinforcing the role of BBS genes in ciliary integrity. The defects in sensory behavior and ciliary morphology lay the groundwork for further studies on BBS mutations.
- Study of the relevance of antioxidant enzymes in thyroid cancerPublication . Freitas, Sílvia; Peixoto, Joana; Máximo, Valdemar; Soares, PaulaThyroid cancer(TC) is the most common endocrine malignancy, arising from follicular and parafollicular cells. Oxidative stress, caused by excess reactive oxygen species(ROS) and metabolites, influences TC development and progression, as the thyroid is highly exposed to ROS. The redox balance is maintained by antioxidant enzymes (SOD, GPX) and non-enzymatic antioxidants, which limit ROS formation and detoxify metabolites. Dysregulation of this balance is observed in various TC types(papillary, follicular, medullary, anaplastic). However, the role of antioxidants in TC progression, prognosis, and therapy remains under study. This project aims to explore the correlation between antioxidant enzyme expression and clinicopathological factors to address their role in TC. A series of 90 TC samples were collected, corresponding to benign and malignant lesions. The protein expression pattern of superoxide dismutase 1(SOD1), superoxide dismutase 2(SOD2) and glutathione peroxidase 1(GPX1) was optimized and assessed by immunohistochemistry in formalin-fixed paraffin-embedded samples for this cohort. In addition, the mRNA expression of SOD1, SOD2 and GPX1 are underway by quantifying mRNA expression using real-time quantitative PCR(qPCR). Our series comprise the following histotypes: Multinodular Follicular Disease(2.2%), follicular adenoma(17.8%), fetal adenoma(7.8%), papillary thyroid carcinoma (PTC)(31.1%) - classic PTC(5.6%) and follicular variant of PTC(11.1%) - follicular thyroid carcinoma(12.2%), oncocytic carcinoma(1.1%), medullary thyroid carcinoma(3.3%) and others(26.7%). QuPath evaluation of immunohistochemical analyses are underway being validated by a specialized pathologist. In parallel, qPCR analysis is ongoing. Clinicopathological parameters will be correlated with the expression patterns of the analyzed molecules. We expect to disclose the expression of antioxidant enzymes in TC and assess their potential as diagnostic and prognostic biomarkers.
- ViruScopeDB: a comprehensive multi-omics database for highly infectious virusesPublication . Lima, Ana; Carneiro, João; Sousa, Sérgio; Sá, Vítor; Pratas, Diogo; Sá, Vítor J.Highly infectious viruses such as HIV, Ebola, and SARS-CoV-2 have presented ongoing challenges to global health. Consequently, the optimization of rapid detection tests, including PCR, and the identification of new therapeutic targets remain of paramount importance. The development of genomic and proteomic databases like the HIV Oligonucleotide Database (HIVoligoDB) [1], EbolaID [2], and CoV2ID [3] has facilitated the accumulation and accessibility of knowledge through comprehensive, user-friendly, open-access platforms. This study aims to update, expand, and integrate these databases into a single resource, ViruScopeDB, while conducting thorough analyses of informative genomic regions with the goal of enhancing viral detection methods and treatment strategies. Complete genomic sequence variants for each virus were compiled using NCBI Virus, followed by multiple sequence alignment via MAFFT within the Galaxy platform. The alignments were consequently uploaded to Geneious Prime for complete genome visualization and calculation of parameters such as percentage of pairwise identity. Primer data was extracted from open-access research articles available on PubMed using a newly-built custom pipeline for PDF to plain text conversion followed by data mining of oligonucleotide sequences. A fully automated script for primer validation, parameter scoring and calculation of best primer pairs for PCR is being constructed for subsequent upload into the database. A total of 658 sequences with a mean length of 18,910 base pairs (bp) were collected for Ebolavirus, with percentage of pairwise identity (PPI) of 91.7%. 7,261 sequences with a mean length of 8,883 bp, with a PPI of 80.8% were identified for HIV-1. For HIV-2, 43 sequences with an average of 10,108 bp and PPI of 80.9% were analyzed. For Ebola, a total of 709 primers were scraped from 257 articles, and for HIV articles this number rises to 10,290 primers collected from 2,579 articles. Using a combination of preexistent and novel custom-built bioinformatics tools, it was possible to data mine key information related to each virus and their variants, as well as collect primer information for possible PCR optimizations. Further analysis will be conducted on the data collected, branching out into the realm of phylogenetics and 3D modelling/viral protein docking, in order to construct a database that is transversal to various omics.