ESS - CQB - Comunicações em eventos científicos
Permanent URI for this collection
Browse
Recent Submissions
- Utilizing spent yeast for tannin adsorption in chestnut shell treatment solutionsPublication . Vieira, Elsa F.; Amaral, Tomás; Ferraz, Ricardo; Delerue-Matos, Cristina; Ferraz, RicardoThis study evaluated the use of brewer’s spent yeast (BSY) as an adsorbent for tannins from a chestnut shell extract (CS tannin extract). This extract was derived from an alkaline treatment (5% NaOH (v/v)) to recover cellulosic material from chestnut shells and needed valorization. Various BSY treatments, including lyophilization, immobilization in calcium alginate beads, and alkaline and acid treatments, were tested to identify which had the best tannin adsorption capacity. The results highlight BSY’s potential as a system to valorize tannins from this treatment solution.
- Deciphering the influence of CD276 glycocode in gastric cancer immunoregulationPublication . Magalhães, Mariana; Dourado-Gonçalves, Martina; Santos, Lúcio Lara; Peixoto, Andreia; Ferreira, José AlexandreGastric cancer (GC) ranks 5th globally in incidence and cancer-related mortality, with advanced-stage 5-year survival rates below 20%1,2, unveiling the need for novel immunotherapies. CD276, an immune checkpoint molecule, is related to immune evasion and tumour progression in GC3-5. In turn, aberrant glycosylation, especially truncated O-glycans, Tn and Sialyl-Tn, correlates with GC aggressiveness and poor prognosis6. Its clinical impact relies on the modulation of protein function and immune escape5,7. This study hypothesizes that CD276 glycosylation may offer new targets for immunotherapy in GC. Methods: CD276 expression was assessed in AGS and MKN-45 cell lines using qPCR and immunoblotting. Glycoengineered AGS and MKN-45 cell lines with truncated glycosylation (C1GALT1 KO) and wild-type (WT) controls were analysed similarly. In vitro proliferation, migration and invasion assays were conducted. CD276 expression was assessed in AGS and MKN-45 cell lines using qPCR and immunoblotting. Glycoengineered AGS and MKN-45 cell lines with truncated glycosylation (C1GALT1 KO) and wild-type (WT) controls were analysed similarly. In vitro proliferation, migration and invasion assays were conducted. Both cell lines have CD276 expression in WT cells. CRISPR/Cas9-mediated knockout of C1GALT1 did not significantly alter CD276 protein or mRNA expression levels. The proliferation assay did not show any changes in either cell line. However, migratory and invasive assays promoted a cell line-dependent response. The migratory capacity of AGS decreased with truncated glycosylation while increasing for MKN-45. C1GALT1 KO AGS cells showed enhanced invasiveness. Aberrant glycosylation in AGS and MKN-45 cells did not affect CD276 expression in vitro, suggesting a CD276 expression independent of O-glycan elongation in GC. Tn/STn glycophenotypes have a cell line-dependent functional impact in GC, suggesting glycosylation-related migration and invasion capacities. Future proteomic studies will clarify the results. Moreover, further research will identify CD276 glycoproteoforms and assess CD276 abrogation effects on T-cell immunomodulation and cytokine profiles. This research may contribute to the development of novel targeted therapies and improved patient outcomes in GC.
- MicroRNA-mediated control of mesenchymal stem/stromal cell senescence: A comparative in vitro studyPublication . Giestinhas, Andrea; Moura, Sara Reis; Silva, Elsa; Nascimento, Diana; Almeida, Maria InêsOsteoarthritis is a growing health problem, aggravated by aging. Mesenchymal stem/stromal cells (MSCs) emerged as a promising cell-based therapy for this disease. However, in vitro expansion of MSCs can result in cell senescence. MicroRNAs (miRNAs) are key regulators of senescence pathways, making them attractive targets to decrease senescence. This work aims to identify senescence-related miRNAs, with the long-term goal to optimize large-scale MSC expansion. Human primary MSCs from 30-60 years patients were isolated and characterized. Senescence was induced by exposing MSCs to 5, 10 and 20 Gy of gamma radiation or to 200, 400, 600 μM of hydrogen peroxide (H2O2). Senescence was confirmed by β-Galactosidase staining along with fluorescence immunocytochemistry to assess Ki67 (proliferation marker) and γH2AX (DNA damage marker). Senescence associated with miRNAs were analyzed by RT-qPCR. Statistical analysis was performed using GraphPad Prism 8.0 (P-value<0.05 was considered statistically significant). Radiation successfully induced senescence in MSCs, particularly in the 20 Gy condition compared to the control. Specifically, γH2AX increased 60%, Ki67 decreased 25%, and β-Gal levels were increased. miR-29 family and miR-34a were upregulated at 20Gy compared to the control, while no differences were found for miR-16, miR-195, and miR-126. On the other hand, neither of the tested H2O2 concentrations showed significant differences in inducing senescence in MSCs. Our data shows that gamma radiation can be used as an in vitro model to induce MSC senescence and to identify senescence-associated miRNAs, while single treatments with H2O2 do not significantly impact senescence.
- Uncovering the mechanisms of protection during mycobacterium tuberculosis infectionPublication . Queirós, Sofia; Silva, Marta L.; Fernandes, Ana I.; Medina-Lopes, Mónica; Saraiva, Margarida; Cardoso, Marcos SantosTuberculosis (TB) is one of the most devastating infectious diseases affecting humankind, having caused 1.25 million deaths in 2023. The identification of effective protective mechanisms in TB could critically contribute to the urgent need of new therapies to stop TB. It is known that genetically related Mycobacterium tuberculosis (Mtb) isolates shape the immune response and disease outcomes. Using the natural genetic diversity of Mtb as a tool to understand protection in TB, my project focuses on the slow progressing infection caused by Mtb isolates of lineage 6 (L6), in which we hypothesize that critical protective mechanisms operate. Analyses of in vitro (macrophages) and in vivo (mouse) infections were performed in susceptible C3HeB/FeJ or resistant C57BL/6 mice, to compare the immune response and outcome of infection caused by Mtb belonging to L6 or L4. Results: In vitro (macrophage) infections showed that both Mtb L6 and Mtb L4 isolates grow overtime, but Mtb L6 grows slower than Mtb L4. In vivo, we found that C57BL/6 mice infected with Mtb L6 offer a unique model of full protection. Strikingly, flow cytometry analysis revealed a faster recruitment of activated CD4+ T cells to the lungs in the Mtb L6-infected C57BL/6, which might suggest that protection may be achieved by this early T cells recruitment. Our results indicate that a slower growth of Mtb L6 in macrophages together with earlier T cell responses in the lung may underlie fully infection control. The ongoing RNA-sequencing analyses will highlight putative protective immune mechanisms operating in this model, of great interest to devise new strategies to control TB.
- 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.
- A practical case of mentoring in higher education at a health schoolPublication . Saúde, Miguel; Ferraz, Ricardo; Silva, Vítor; Barreto, João; Portugal, Paula; Santos, Joana; Vieira, Mónica; Vieira, Mónica; Santos, Joana; Barreto, João Francisco; Simões-Silva, VitorThe rapid advancement of Generative Artificial Intelligence (AI) tools is reshaping higher education, particularly in creative fields such as design, multimedia, and audiovisuals. Students increasingly seek faster solutions for academic challenges, often relying on AI-generated content rather than engaging in research, critical analysis, and validation through credible sources or instructors. This tendency weakens the "thinking vs. creating" stage of the design methodology, a fundamental cognitive process that requires deep concentration, research, and creative reasoning to materialize ideas effectively. The proposed design methodology consists of four stages: (1) Briefing—problem definition, (2) Thinking vs. Creating—ideation, (3) Materialization—execution based on Lupton’s (2016) Design Thinking principles, and (4) Solution—evaluating originality, relevance, and creativity. In practical-laboratory classroom settings, students engage in manual techniques such as mind maps and moodboards (A2 format). Initially, they hesitate to move away from digital tools but later recognize the cognitive and creative benefits of these techniques. This process reinforces the understanding that strong ideas require effort rather than instant AI-generated solutions. A survey had a total of 256 answers of students in Communication Design, Multimedia, and Audiovisuals, revealed that 64.8% use ChatGPT, 28.9% Capcut, 19.5% Copilot, 13.3% Adobe Firefly, 11.7% DALL·E, and other AI tools. However, only 41.4% critically reflect on AI-generated content, 17.6% validate it with teachers, and 14.5% verify information through online sources. This study concludes that while AI accelerates and optimizes aspects of the creative process, human cognitive engagement remains essential. The integration of AI in co-creation processes, particularly at the "thinking vs. creating" stage, enhances skill development when used as a complementary tool rather than a replacement for critical and creative thinking.
- Goji berries (Lycium barbarum) extract as new potential cosmetic ingredient – A first screeningPublication . Silva, Joana; Teixeira, Filipa; Silva, Ana M.; Vieira, Mónica; Amaral, M. Helena; Rodrigues, Francisca; Vieira, MónicaCurrently there is greater concern about appearance and skin care products. Although cosmetic products are not associated with serious health problems, there are concerns related to undesirable effects due to the presence of potentially carcinogenic and allergenic ingredients. Thus, consumers have been increasingly looking for products of natural and plant-based origin. The use of these products is expected to increase exponentially, and studies are urgently needed to introduce new products into the market. Goji berry is a fruit with increasing popularity due to its richness in phenolic compounds, carotenoids, organic acids, carbohydrates, and vitamins. Its antioxidant, antimicrobial and anticancer activities make this product promising for cosmetic applications. The aim of this study was to study an ecological extract obtained from goji berries through ultrasound-assisted extraction as a new ingredient incorporated into a cosmetic formulation. Goji berry extract was obtained by ultrasound-assisted extraction, according to Silva et al. . To assess safety, in vitro assays were carried out on skin cell lines. Subsequently, several cosmetic formulations incorporating the extract were developed and characterized. The results demonstrated that goji berries have no toxicity on skin cell lines. Cosmetic formulations containing the goji berries extract demonstrated to be suitable for application to the skin and maintained their characteristics during the storage period. Goji berries extract is safe and stable in cosmetic formulations, proving to be suitable for consumer needs.
- Phagetherapies for infections caused by P. aeruginosaPublication . Ferraz, Ricardo; Reis, Ana; Prudêncio, Cristina; Baylina, Pilar; Fernandes, Rúben; Ferraz, Ricardo; Prudêncio, Cristina; BAYLINA MACHADO, PILAR; Fernandes, RúbenThe hospital infections can be prevented by controlling some factors related with staff, material, and environment. At this moment the existing legislation regulates procedures that prevent the propagation of the infection and/or of the agents that causes it. The Pseudomonas aeruginosa is a gram-negative opportunistic responsible for most of the hospital infections. Because it is opportunistic it is more frequent in immunocompromised patients submitted to transplants and surgical interventions. In short, this thesis has contributed for the understanding of the biology of P. aeruginosa , antibacterial treatment and its resistance to this treatment by using efflux bombs, and so as establishing associations with others factors, such as biochemical. This study has the objective to understand the resistance factors used by the P. aeruginosa in order to develop alternative therapies for this agent. Initially, 72 hospitalar isolated were characterized and 91.67% have revealed more than 3 classes of Antimicrobians.
- In vivo activity of peptide-ionic liquid conjugates against diabetic woundsPublication . Gomes, A.; Ferraz, Ricardo; Ferreira, M.; Maciel, J.; Plácido, A.; Leal, E.; Gameiro, P.; Gonçalves, Teresa; Carvalho, E.; Gomes, P.Due to widespread multidrug-resistant (MDR) microbes, efficient treatments for infected wounds are being exhausted, which means that there is an alarming lack of effective antibiotics to treat diabetic foot ulcers (DFU). The increasing life expectancy of the population and the growing incidence of unhealthy lifestyles is leading to a concerning rise in the number of people affected with diabetes and related complications, being DFU amongst the most troublesome. In 2014, already about 11% of the Portuguese population had diabetes and this number is continuously growing every year. [1] Like other chronic wounds, DFU are difficult to heal, but their association with other diabetes complications, such as peripheral neuropathy and ischemia, underpin an exceedingly low healing rate and high propensity for persistent infections. In connection with the above, we have recently advanced peptide-ionic liquid conjugates (PILC) as potential active pharmaceutical ingredients for topical formulations to tackle DFU. PILC combine a short cosmeceutical peptide with collagenboosting action, with an ioni q b , k “ k” -catalyzed azide-alkyne cycloaddition reaction. This revealed one conjugate with an outstanding performance in vitro, namely, potent collagen-inducing effect, alongside microbicidal (bactericidal and fungicidal) action.[2] This conjugate was now tested for its wound healing ability in a mouse model of streptozotocin (STZ)-induced type 1 diabetes. The promising results obtained thus far in this animal model, alongside biophysical investigations on the potential antimicrobial mechanism of action of PILC, will be presented in this communication.
- Surface-active ionic liquids derived from antimalarial drugs and natural lipids that display multi-stage antiplasmodial activityPublication . Ferraz, Ricardo; Silva, Ana Teresa; Oliveira, Isabel S.; Duarte, Denise; Moita, Diana; Nogueira, Fátima; Prudêncio, Miguel; Gomes, Paula; Marques, Eduardo F.The use of Ionic Liquids (ILs) in Medicinal and Pharmaceutical Chemistry has been greatly evolving since they were first used as alternative solvents for the chemical synthesis of active pharmaceutical ingredients (APIs). ILs are now used with other purposes in this area, such as adjuvants in drug formulation and delivery, or even as bioactive compounds per se. New ionic structures with biologically relevant properties can be easily obtained through straightforward reactions, as nearly all APIs are ionizable and can be paired with counter-ions that could be either inert or offer additional beneficial biological effects. This efficient, cost-effective strategy for the rescuing and repurposing of drugs is particularly appealing for finding new options to combat "diseases of poverty" like malaria. We implemented this approach to “recycle” classical antimalarial aminoquinolines, namely, chloroquine (CQ) and primaquine (PQ), by pairing them with natural acidic lipids through acid-base reactions. Our goal was to create novel ILs capable of targeting multiple stages of the Plasmodium parasite’s life cycle. Additionally, we were interested in that such ILs could act as surface-active ionic liquids (SAILs), able to self-assemble into nanostructures displaying adequate bioavailability. For this purpose, we paired the antimalarial drugs with either fatty acids or bile acids, due to their biocompatibility and amphiphilic nature. The antiplasmodial activity and self-aggregation properties of the new SAILs were determined. PQ fatty acid salts preserved the liver-stage antiplasmodial activity of the original drug, while exhibiting significantly enhanced activity against blood-stage parasites. In the case of bile salts, those derived from PQ retained the efficacy of the parent drug, whereas the CQ-derived salts proved to be novel triple-stage antiplasmodial agents. The SAILs obtained from bile acids showed a remarkable ability to self-aggregate, with a notably lower critical micelle concentration compared to their respective sodium salts. Overall, these findings open a new strategy for drug repurposing, extending beyond antimalarials and other anti-infective therapies.