Faculdade de Medicina e Ciências Biomédicas
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Percorrer Faculdade de Medicina e Ciências Biomédicas por Objetivos de Desenvolvimento Sustentável (ODS) "09:Indústria, Inovação e Infraestruturas"
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- Activity induced genes expression is impaired in polyglutamine spinocerebellar ataxiasPublication . Torquato Afonso, Inês; Vilhena Catarino Brito, David; Bading, Hilmar; Nóbrega, ClévioPolyglutamine Spinocerebellar ataxias (SCAs) are a group of 6 incurable genetic disorders, caused by an expansion of the trinucleotide cytosine-adenine-guanine in their causative genes, which produces a protein with an expanded glutamine region. This project focuses on the study of Spinocerebellar ataxia type 2 (SCA2) and type 3 (SCA3) (1), which are rare dominantly inherited disorders that primarily impair the cerebellum therefore leading to motor ataxia. Activity-induced inhibitor of death (AID), are a group of pro-survival 9 genes which were found to be neuroprotector in several neurological disorders, including stroke, glaucoma, AD, HD, and ALS (2). In this project, we aim to investigate about the relevance of the expression of AID genes for cerebellum function and whether their expression levels are impaired in SCA2 and SCA3
- AI-enhanced adaptive testing with cognitive diagnostic feedback and its association with performance in undergraduate surgical education: a pilot studyPublication . Gonçalves, Nuno Silva; Collares, Carlos; Pêgo, José MiguelBackground: Effective feedback in the cognitive domain is essential for surgical education but often limited by resource constraints and traditional assessment formats. Artificial Intelligence (AI) has emerged as a catalyst for innovation, enabling automated feedback, real-time cognitive diagnostics, and scalable item generation, thereby transforming how future surgeons learn and are assessed. Methods: An item bank of 150 multiple-choice questions was developed using AI-assisted item generation and difficulty estimation. A formative Computerized Adaptive Testing (CAT), balanced across three cognitive domains (memory, analysis, and decision) and surgical topics, was delivered via QuizOne® 3–5 days before the summative Progress Test. A total of 147 students participated, of whom 116 completed the formative CAT. Performance correlations, group comparisons, analysis of covariance (ANCOVA), and regression analyses were conducted. Results: Students who voluntarily completed CAT showed higher Progress Test scores, though causality cannot be established due to self-selection bias (p = 0.021), with the effect persisting after adjusting for prior academic performance (ANCOVA p = 0.041). Memory skills were the strongest predictors of summative outcomes (R2 = 0.180, β = 0.425), followed by analysis (R2 = 0.080, β = 0.283); decision was not significant (R2 = 0.029, β = 0.170). Conclusion: AI-enhanced CAT–Cognitive Diagnostic Modeling (CDM) represents a promising formative approach in undergraduate surgical education, being associated with higher summative performance and providing individualized diagnostic feedback. Refining feedback presentation and enhancing decisionmaking assessment could further optimize its educational impact.
- Assessing the role of CT imaging in identifying candidates for neoadjuvant chemotherapy in right colon cancer: a critical analysisPublication . Lopes, João Leão; Soares, Ana Sofia S.; Mendes, Beatriz; Tomada, Elisa Paoluzzi; Cunha, Miguel F.; Melina Fernandez, Laura; Amorim, Edgar; Azevedo, José; Parvaiz, AmjadBackground and purpose Standard treatment for localized right colon cancer is radical surgery, followed by adjuvant chemotherapy for stage III or intermediate MSS and high-risk stage II tumours. Recent studies suggest a benefit from neoadjuvant chemotherapy (NAC), particularly for T4b and/or N+tumours. Patient selection for NAC relies on CT-based clinical staging, but the accuracy of CT in detecting high-risk features is variable, raising concerns about potential overtreatment. The study aims to demonstrate the accuracy of CT staging of the right colon with the purpose of indicating neoadjuvant CT. Methods Patients undergoing curative right hemicolectomy between 2013 and 2023 at two Portuguese institutions were included. All had preoperative CT; those receiving NAC were excluded. Sensitivity, specificity, positive predictive value, and negative predictive value of CT in identifying T4b and N+tumours were calculated by comparing clinical (cTNM) and pathological (pTNM) staging. Results Among 165 patients (48% male, mean age 70.5 years), CT showed low sensitivity (26%) but high specificity (91%) for pT4b tumours, with a tendency toward understaging. For nodal disease, sensitivity was 87% and specificity 41%. Only 57% of cT4b and/or cN+cases confirmed at least one unfavorable pathological factor, implying potential overtreatment in 43% of patients if NAC were applied solely based on CT findings. Conclusion CT remains the standard for clinical staging but demonstrates limited accuracy in identifying high-risk right colon cancers. NAC decisions should integrate additional criteria beyond CT findings to avoid overtreatment.
- Biomarkers for predicting malignant transformation of premalignant lesions of the larynx: a systematic reviewPublication . Rodrigo, Juan P.; Lima-Souza, Reydson Alcides de; López, Fernando; Stenman, Göran; Agaymy, Abbas; Quer, Miquel; Paleri, Vinidh; Leivo, Ilmo; Nadal, Alfons; Zidar, Nina; Mariano, Fernanda V.; Hellquist, Henrik; Gale, Nina; Ferlito, AlfioBackground/Objectives: Premalignant laryngeal lesions carry a variable risk of malignant transformation to squamous cell carcinoma. Identifying reliable biomarkers that predict malignant transformation could improve patient management and surveillance strategies. The objective of this work is to perform a systematic review of the literature on biomarkers that predict malignant transformation of premalignant laryngeal lesions. Methods: We conducted a systematic review following PRISMA 2020 guidelines. The PubMed, Scopus and Embase databases, and Google Scholar were searched for studies published between January 2011 and November 2025. Studies investigating biomarkers that predict malignant transformation of histopathologically confirmed premalignant laryngeal lesions were included. Risk of bias was assessed using the ROBINS-I tool. Results: From 166 initially identified records, 11 studies met the inclusion criteria, including 730 patients. These studies investigated diverse biomarker categories such as protein markers (cortactin, FAK, NANOG, SOX2, CSPG4), immune markers (tumor-infiltrating lymphocytes, immune gene signatures), microRNAs (miR-183-5p, miR-155-5p, miR-106b-3p), and genetic markers (chromosomal instability, PIK3CA amplification and mutations, FGFR3 mutations). Five studies provided adequate follow-up data on transformation outcomes. Most studies showed a moderate to serious risk of bias primarily due to limited confounder control and incomplete reporting. Conclusions: While several promising biomarker candidates have been identified, the evidence base remains limited due to small sample sizes, heterogeneous methodologies, and inadequate follow-up data. Cortactin/FAK protein expression and immune signatures are the most promising but require validation in larger, well-designed prospective cohorts.
- Biopotential of sea cucumbers (echinodermata) and tunicates (chordata) from the western coast of portugal for the prevention and treatment of chronic illnessesPublication . Carletti, Alessio; Cardoso, Carlos; Juliao, Diana; Arteaga, Jorge L.; Chainho, Paula; Dionísio, Maria Ana; Sales, Sabrina; Gaudêncio, Maria J.; Ferreira, Inês; Afonso, Cláudia; Lourenço, Helena; Cancela, M. Leonor; Bandarra, Narcisa M.; Gavaia, PauloIn the present work, we aimed to explore the potential of two groups of marine invertebrates—sea cucumbers (Echinodermata) and ascidians (Chordata)—as sources of antiinflammatory, anti-oxidant, and osteogenic compounds with potential to be used as pharmaceuticals and nutraceuticals for the treatment and prevention of chronic diseases. 24 extracts (ethanol, water, and ethyl acetate) from 4 species of sea cucumbers and 4 species of tunicates were produced and screened in vitro for their anti-inflammatory and anti-oxidant activities and in vivo for osteogenic activity through an assay using zebrafish larvae. Our results showed that ethanolic extracts presented anti-oxidant and anti-inflammatory activity, which revealed to be stronger in the ascidians. The osteogenic activity, which provides evidence of the bioactive potential of these organisms in preventing chronic disorders causing low bone density, was found to be strong in one species of ascidians and 3 of holothurians. This study demonstrates the high potential of extracts from these marine organisms for using as nutraceuticals in the prevention of chronic bone disorders.
- Chromenone derivatives as CRM1 inhibitors for targeting glioblastomaPublication . Princiotto, Salvatore; Jiménez, Lucía; Domínguez, Lucía; Sequeira, João G. N.; Mourato Paulo, Cristiana Isabel; Orea-Soufi, Alba; da Silva Santos, Bruno Filipe; Dallavalle, Sabrina; Machuqueiro, Miguel; ferreira, Bibiana; Link, WolfgangGlioblastoma (GBM) is one of the most aggressive and deadly cancers. Due to the complexity and redundancy within signaling networks in GBM, targeted inhibitors of specific pathways have shown only limited success. The nuclear export receptor chromosome region maintenance 1 (CRM1) has recently emerged as a promising therapeutic target, as its inhibition can simultaneously disrupt multiple key oncogenic drivers. Herein, whether chromenone derivatives, known for detecting thiol-containing molecules, can function as CRM1 inhibitors is explored. Several chromenonebased derivatives are synthesized and it is demonstrated that they inhibit CRM1-driven nuclear export in a structure- and dose-dependent manner. A preliminary structure–activity relationship is established, providing a rationale for selective CRM1 binding based on molecular docking studies. Additionally, it is showed that the active chromenone derivatives effectively inhibit the nuclear export of endogenous nuclear export signal-containing substrates in GBM cells. Several of these compounds exhibit selective cytotoxicity againstGBM cell lines, highlighting their potential as targeted therapies for GBM.
- Development and psychometric validation of the Minho suture assessment scale (Minho-SAS) for medical studentsPublication . Gonçalves, Nuno Silva; Sousa, Rita Matos; Collares, Carlos; Pereira, Vítor Hugo; Pêgo, José Miguel; Anderson, M. BrownellIntroduction: Even though mastery of suturing is a core technical skill in surgical education, existing tools for its assessment often lack psychometric validation or are not specifically designed for undergraduate training. The aim of this study was to develop and validate the Minho Suture Assessment Scale (Minho-SAS), a structured instrument to evaluate fundamental suturing competencies in medical students. The research question was whether the Minho-SAS demonstrates validity and reliability as a psychometric tool. Methods: The development process involved collaboration with multidisciplinary surgical teams and experienced practitioners to ensure content validity. Data from a cohort of medical students were utilized for psychometric evaluation. Dimensionality was assessed using parallel analysis, Bayesian information criterion, unidimensional congruence, item unidimensional congruence, explained common variance, item explained common variance and mean of item residual absolute loadings. Validity based on internal structure was assessed with Rasch model analysis and factor analysis from the tetrachoric correlation matrix. Reliability was assessed using Rasch model standard errors of measurement to obtain a conditional reliability curve and Cronbach's alpha and McDonald's omega internal consistency coefficients. Results: Analyses supported a unidimensional structure for the Minho-SAS. The single-factor solution explained 39.96% of variance, and Rasch measures accounted for 29.15% (16.43% by persons, 12.72% by items). Residual correlations, factor loadings, and item fit statistics were within acceptable ranges. Reliability indices were satisfactory: Rasch reliability = 0.706; McDonald's omega = 0.889; Cronbach's alpha = 0.883. Conclusion: The Minho-SAS is a robust instrument specifically tailored for assessing fundamental suturing skills among medical students. Rasch model analysis yielded less favorable results than factor analysis, yet still acceptable. While demonstrating considerable potential, further exploration of Minho-SAS across diverse populations and educational settings is crucial to affirm its broader applicability and impact in medical education and clinical practice.
- Dextran as an adjunct in carotid endarterectomy: a systematic review and meta-analysisPublication . Silva-Vieira,Duarte; Pereira-Neves, António; Nzwalo, Hipólito; Myrcha, Piotr; Neves, João RochaBackground: Carotid endarterectomy (CEA) is a widely used surgical procedure to prevent stroke in patients with carotid artery stenosis. Dextran, an antithrombotic agent with antihemostatic properties, has been proposed as an adjunctive therapy to reduce thromboembolic complications during CEA. However, its effectiveness and safety remain controversial. This systematic review and meta-analysis aim to assess the incidence of thromboembolic and hemorrhagic complications in patients undergoing CEA with dextran administration. Methods: A systematic search was conducted in MEDLINE, Scopus, and Web of Science for studies evaluating the postoperative effects of dextran in CEA patients. Random-effects metaanalysis was performed to estimate the pooled incidence of adverse events, and heterogeneity was assessed through meta-regression analysis. The quality of the included studies was evaluated using the National Heart, Lung, and Blood Institute Study Quality Assessment Tool for observational studies and the Cochrane Risk-of-Bias 2 tool for randomized controlled trials (RCTs). Results: Ten studies, including a total of 149,540 patients, met the inclusion criteria. Of these, 9 were observational cohort studies (6 retrospective and 3 prospective), while one was an RCT. The meta-analytical incidence of stroke following CEA with dextran was 0.7% at 30 days post operatively (95% confidence interval, 0.3e1.1%), with moderate heterogeneity (I2 ¼ 50.79%, P ¼ 0.002). Meta-regression analysis indicated that geographic region significantly contributed to heterogeneity (P ¼ 0.010), while other clinical covariates, such as diabetes, hypertension, and coronary artery disease, were not associated with significant variations in outcomes. Dextran was primarily administered selectively to high-risk patients, with variations in dosing protocols across studies. Conclusion: The use of dextran in CEA was associated with a low incidence of thromboembolic events. However, some heterogeneity among studies highlights the need for further large-scale RCTs to clarify its efficacy and safety. Given the potential risks of dextran, including hemorrhage and renal complications, individualized patient selection and standardized administration protocols are recommended.
- Epigenetic regulation of ZNF687 in bone cells: elucidation of its role in the progression of Paget’s disease of bonePublication . Domingos Varela, Débora Cristina; Cancela, Leonor; Conceição, NatérciaPaget’s disease of bone (PDB) is characterized by focal areas of intense bone resorption by hyperactive osteoclasts followed by excessive bone formation by osteoblasts. Mutations and increased expression of ZNF687 have been associated with PDB. However, the role of ZNF687 in bone metabolism is poorly understood, and the molecular mechanisms that regulate its expression remain unknow. Therefore, the main objective of this study was to investigate the regulation of ZNF687 in bone cells, focusing on epigenetic mechanisms, in order to elucidate its involvement in the pathophysiology of PDB. In addition, we performed a genetic analysis of ZNF687, along with other candidate genes, in a cohort from southern Portugal. First, we characterized the human ZNF687 promoter, evaluated the functionality of predicted binding sites for bone-related transcription factors, and assessed the impact of CpG methylation on its regulatory activity. Our results indicate that NFκB, PU.1, DLX5, and SOX9 act as transcriptional regulators of ZNF687, and that DNA methylation inhibits their regulatory activity. Next, we analyzed mice Zfp687 expression and epigenetic regulation in MC3T3-E1 osteoblast differentiation and in hindlimb bones throughout mice life stages. Our results suggest that miR-142a-3p targets Zfp687 3′UTR, contributing to its downregulation during osteoblastogenesis, while DNA methylation does not appear to regulate Zfp687. In the PDB genetic study of Portuguese population, we identified the ZNF687 c.2810C>A variant that was predicted in silico to be pathogenic and shown in vitro to enhance nuclear import. In addition, OPTN rs2234968 variant was significantly associated with PDB. Finally, we examined ZNF687 expression and CpG methylation during in vitro osteoclast differentiation. ZNF687 was upregulated during murine osteoclastogenesis and overexpressed in osteoclasts from PDB patients in comparison to those of healthy controls. Moreover, methylation levels in -506/-396 promoter region were significantly higher in osteoclasts from PDB patients compared to their undifferentiated precursors and healthy osteoclasts. In summary, this work evidences the involvement of epigenetic mechanisms in bone cells’ differentiation, particularly in the regulation of the ZNF687 gene during osteoclast and osteoblast differentiation. Furthermore, it suggests that DNA methylation may contribute to the upregulation of ZNF687 in PDB.
- Exploring angiogenesis and cardiomyocyte differentiation in left ventricular noncompaction using patient derived hiPSCPublication . Carmo, Sara Martins do; Bragança, JoséLeft ventricular noncompaction (LVNC), is a rare cardiomyopathy characterized by a spongy myocardial structure, hyper-trabeculation and intra-trabecular recesses, resulting from failure of normal embryonic compaction of the myocardium. The prevalence of LVNC varies globally, between 9.5% in paediatric age and 0.05-0.25% in the general population. Multiple genetic mutations are associated with LVNC, affecting sarcomeric, cytoskeletal and mitochondrial functions. This study investigates the genetic mechanisms underlaying LVNC, focusing on mutations involved in heart diseases and their impact in cardiomyocyte differentiation and angiogenesis, with a special focus on ZSCAN10, SCN10A and VE-PTP, found mutated in the patient’s cells used in this study. Cardiomyocytes were differentiated from induced pluripotent stem cells (iPSCs) derived from a LVNC patient and a 1st degree healthy relative. Gene relative expression analysis of samples collected during cardiomyocyte differentiation, highlighted significant differences on in key genes, such as GATA4, ISL1, SOX17, KDR, VE-PTP, VEGFA, TNNT2 and NKX2.5 in patients derived cells compared to control cells. Among those, GATA4, ISL1 and NKX2.5, which were previously showed to cooperate for the differentiation and proliferation of cardiomyocytes, presented a significantly lower expression. SOX17, KDR and VEGFA have functions in cardiac vascularization, and the expression of SOX17 was higher in patient’s cells, while in the same conditions KDR and VEGFA were decreased at critical time points for endothelial cells differentiation. Thus, the expression of these genes, crucial for cardiomyocyte development and angiogenesis, were markedly altered in LVNC-derived cells compared to control cells. A Tube formation assay using endothelial cells from both LVNC-derived and control cells, to assess their ability to form capillary like structures. Remarkable differences were observed, with patient cells showing a delayed and an impaired tube formation, and a reduced vascular network complexity. Overall, our results argue that novel genetic and cellular mechanisms might be altered in the LVNC patient cells analysed.