Browsing by resource type "conference poster"
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- Analyzing Total Hip Arthroplasty: Straight Stem vs Anatomical Stem with Different Materials and ActivitiesPublication . Queirós, Pedro; Gueiral, Nuno; González-Gómez, Carlos David; Gueiral, Nuno[Introduction] Total Hip Arthroplasty involves replacing damaged parts of the hip joint with a prosthetic comprised of an artificial acetabular cup and femoral head. These components, made of durable, low-friction materials, aim to restore mobility, and alleviate pain in patients with hip joint degeneration, such as osteoarthritis or fractures. Utilizing computational mathematical models, such as the finite element method (FEM), it is possible to predict the behavior of materials under simulated loads from common daily activities [1], thereby anticipating potential failures in the femoral stem or the material itself.
- Bioacessibility of zinc in pet food determined by a dynamic leaching methodPublication . Fernandes, Sara R.; Pereira, Ana Margarida; Matos, Elisabete; Castanheira, Francisco; Baptista, Cláudia S.; Cabrita, Ana Rita J.; Segundo, Marcela A.; Fernandes, SaraIn dynamic leaching methods, portions of extractant reagents are continuously provided to the solid sample contained in flow-through microcolumns or chambers, enabling the renewal of extracting fluid and avoiding saturation effects from fluid stagnation. These methods are also suitable for fast measurements in real time with small extract manipulation, especially when coupled online with suitable detectors [1]. In this work, the bioaccessible fraction and kinetic leaching profile of zinc in pet food was determined using a robust flow-through device, composed by two filters placed in polypropylene holders to entrap the solid sample, designed for dynamic leaching experiments [2]. Continuous extraction flow was ensured by a peristaltic pump connecting the extraction reservoir and the extraction chamber, at a flow rate of 0.5 mL min-1. Synthetic fluids simulating digestive compartments were applied as extractants. The kinetic extraction profile of fast leachable Zn was evaluated by flame atomic absorption. Operational conditions, including filters’ composition and pore size, were tested. Preliminary results have shown that different extracting fluids (with and without digestive enzymes) had an influence on the total amount and on the leaching kinetic profile of Zn. In fact, higher values were obtained when enzymes were present in the extracting fluids. The proposed dynamic leaching method was suitable for evaluation of bioaccessible Zn in pet food. This information will be applied for the improvement of Zn supplementation in dog foods and for designing new products with enhanced mineral delivery.
- Bioprospecting for cellulose-degrading microorganismsPublication . Almeida, Liliana; Alexandrino, Diogo; Oliveira, Rui S.; Carvalho, M. Fátima; Freitas, Marisa; Freitas, MarisaCellulose, a complex polysaccharide, is one of the main components of plant and algae biomass and therefore the most abundant polymer found in nature, serving as a significant carbon source in various ecosystems. Bioprospecting for cellulolytic microbes is a promising strategy for discovering potential biocatalysts for the hydrolysis of lignocellulosic materials, including residues. This work aims to assess the cellulolytic potential of microbial isolates (bacteria and fungi) sourced from diverse environments and to establish a synthetic microbial consortium capable to enhance the management of cellulosic waste. The experimental approach encompasses biodegradation assays coupled with optimized colorimetric methods, to estimate cellulose consumption (Congo Red assay) and the concomitant production of oligomeric/monomeric sugars (Dinitrosalicylic acid assay). For bacterial strains, these biodegradation assays involve batch incubations in minimal liquid medium supplied with cellulose as the sole carbon source, while solid medium is being used for fungi. Both assays are being run under mesophilic temperatures (28-30 ºC) and aerobic conditions. Upon achieving a final selection, strains exhibiting the best cellulose degradation performances will be assembled into a synthetic consortium that will be evaluated for their cellulose degradation capability. Future steps will also include phylogenetic identification of the cellulose degrading isolates through 16S and ITS rRNA gene sequence analysis. This study has the potential to identify novel cellulolytic microbes, highlighting the substantial role microorganisms play in ecosystem processes and their diverse applications in biotechnology.
- Co-pyrolysis of brown macroalgae and pinecones in a fixed bed reactorPublication . Silva, F.T.; Nascimento, M.; Pilão, R. M.; Neto, M.P.; Ribeiro, A.M.This study presents results on the slow co-pyrolysis of Laminaria digitata (LD) and pinecones (PC), at an average temperature of 560 °C, for mass ratios LD/PC of 100/0, 50/50, 30/70, 10/90 and 0/100. The biochar yields varied from 35.3 to 31.2 %, for bio-oils, the yields were in the range of 23.3 to 39.9 %, and for the gas phase, between 41.4 to 28.9 %, as the amount of PC increased in the feeding mixture. The biochars were characterized in terms of proximate analysis and higher heating value (HHV). The properties of bio-oils that were determined included pH, density and HHV, as well as identification of compounds by infrared analysis. CO2, CO, CH4 and H2 were identified in the gas phase of all the experiments by gaschromatography, but the most produced gas was CO2, followed by CO.
- Correlation between rhinomanometry and spirometry parameters in 971 adultsPublication . Gonçalves, Ivânia; Jacinto, Tiago; Amaral, Rita; Pereira, Ana M.; Araújo, Luís M.; Couto, Mariana; Fonseca, João A.; Amaral, RitaThere is a lack of published studies about the association between rhinomanometry and spirometry results. Some studies have shown a moderate correlation between spirometry parameters and other nasal objective measures such as Peak Nasal Inspiratory Flow (PNIF). We aimed to study the correlation between rhinomanometry and spirometry parameters.
- Creation of a fungal library and screening of antimicrobial and anticancer activityPublication . Ferreira, Diogo; Hermida, Lara Areal; Rocha, Ana Catarina; Baylina, Pilar; Sieiro, Carmen; Fernandes, Rúben; BAYLINA MACHADO, PILARAccording to the World Health Organization, cancer and infectious diseases are two of the most problematic diseases nowadays. Cancer kills 10 million people every year and the emergence of resistance to antitumoral drugs is an important medical challenge. At the same time, antimicrobial resistance (AMR) is also a serious threat to human and environmental health. Besides mortality, AMR burdens healthcare services and dampens medical procedures such as surgeries, cancer treatments and other invasive procedures. The development of new drug therapies to fight drug resistance is essential to contest the rising of resistant bacteria and reduction of the effectiveness of antitumoral drugs. Microorganisms have been a major source for natural compounds throughout the years. Fungi, renowned for their ability to produce an array of broad and diverse secondary metabolites, offer a rich resource for drug discovery. We built a collection of fungal species, isolated from chestnuts, sunflower seeds, and chestnut flour, and explored their extracts for potential antimicrobial and anticancer activity. Fungi cultures for secondary metabolite biosynthesis were done in submerged fermentation in Malt Extract broth for 15 days at 26 °C. Liquid-liquid extraction techniques, with ethyl acetate as a solvent, were applied to obtain crude secondary metabolite extracts. Clinical resistant bacteria, yeasts, and prostate cell lines (human prostate epithelial cells – HpepiC; human caucasian prostate adenocarcinoma cells - PC3) were exposed to fungal extracts at a single concentration of 100 µg/mL. Our results so far show several extracts with antimicrobial and/or anticancer activity without decreasing cell viability of non-tumoral cells, showing their potential as therapeutic drugs without possible secondary effects. Although, more studies should be done, and pending fungal identification will allow us to select which extracts will be further investigated to find if the displayed bioactivity could be happening due to unknown natural compounds
- Deciphering neuroimmune interactions in alcohol intake in mouse model of intermittent access in male and femalePublication . Pacheco, Raquel; Canedo, Teresa; Rodrigues, Ana M.; Moreira, Joana; Relvas, João B.; Socodato, Renato; Summavielle, Teresa; Summavielle, TeresaExcessive alcohol consumption continues to pose a significant global health challenge, with detrimental effects on millions of individuals. Our laboratory has shown that alcohol exposure triggers reactive changes in astrocytes, including alterations in gene expression, activity, and proliferation, while also affecting microglial morphology and immune responses. We are to characterizing the effects of chronic alcohol consumption using a wellestablished voluntary alcohol drinking model in adult mice, to investigate the impact of chronic alcohol exposure on the prefrontal cortex (PFC), focusing on glial cell morphology, synaptic density, and behaviour. Mice are exposed to intermittent “every-other-day” (EOD) access to alcohol 15% (v/v) for 3 weeks, and behaviourally tested for anxiety, depression and memory, before sacrifice at 21 days of alcohol, or at 7 days of withdrawal. Brains were processed for glial cell analysis. Our preliminary findings revealed sex-specific responses following chronic alcohol exposure. Male mice exhibited increased astrocyte volume in the ventromedial PFC (vmPFC) and hyper-ramification in the ventrolateral PFC (vlPFC), whereas females displayed reductions in astrocyte size and complexity. Microglia morphology also differed between sexes, with females showing increased cell volume and males displaying reduced microglial volume in the vlPFC. These results suggest distinctive immune and synaptic responses to ethanol in males and females. Of note, we observed heightened inhibitory synapse density in the male PFC, while females exhibited increased excitatory synapse density. We are now conducting a proteomic analysis of PFC synaptosomes to identify important molecular targets in the crosstalk between neuros and glial cells. With this work we expect to clarify the complex interplay between chronic ethanol exposure, sex, and PFC function, find also new targets for innovative therapeutic approaches.
- Decoding immunomodulatory interactions: Exploring the crosstalk between bone marrow-derived mesenchymal stem cells (BM-MSCs) out the bag and peripheral blood mononuclear cells (PBMCs) for potential in-vivo immunosuppressionPublication . Monteiro, Raquel L.; Lopes, Sérgio M.; Roncon, SusanaAllogeneic hematopoietic stem cell transplant is vital for haematological diseases, yet chronic complications arise as donor immune cells start attacking patient tissues. A lab barrier to studying this alloreactivity is the absence of the hematopoietic stem cell niche. Here, we employed BM-MSCs from discarded collection bags to solve this hurdle. The aim was to modulate PMBC proliferation in vitro, downregulating alloreactivity and proposing immunomodulation mechanisms. Responder PBMCs were labelled with CFSE dye, and stimulator cells irradiated. Co-cultured in a 2:1 ratio to mimic alloreactivity in MLR assays (n=3) for 6 days, with or without BM-MCs. MSC phenotype examined pre- and post-co-culture. Flow cytometry examined PBMC proliferation through CFSE histograms and assessed surface marker expression of CD45+, CD3+, CD4+, CD8+, CD19+, CD56+ and CD14+. Resazurin assays tracked metabolic activity. CFSE immunofluorescence recorded PBMC proliferation, while phase-contrast images showed PBMC-MSC physical interactions. Data is shown as mean ± standard deviation. Statistical significance assessed with Two-Way ANOVA test (p<0.05). BM-MSCs expanded successfully, maintaining ideal phenotype and function. CD44+ expression increased significantly in MSCs post-culture. CFSE expression aligned only with PBMC format, whilst phase-contrast images revealed closer alignment in co-culture. Metabolic activity showed enhanced metabolism in PBMCs/MSCs co-culture, with a 15% reduction in proliferating responder cells. March's pending immunophenotyping results will enhance understanding of the observed immunosuppression. Expanding BM-MSCs from discarded bags unravelled immunosuppression in alloreactive conditions. BM-MSCs, lacking CD44, had increased expression due to in-vitro cultivation. Reduced alloreactive PBMC proliferation by 15% highlights MSCs' immunosuppressive potential. Upcoming immunophenotyping insights will detail the immunosuppression seen.
- Determination of Vitamin C content in spinach plants grown under the use of cyanobacteria biomass as fertilizerPublication . Martins, Diogo; Massa, Anabella; Reimão, Mariana; Vasconcelos, Vítor; Campos, Alexandre; Pinto, Edgar; Freitas, Marisa; REIMÃO BORGES LOPES DA SILVA, MARIANA; Pinto, Edgar; Freitas, MarisaThe agricultural sector is continuously exploring sustainable and innovative approaches to enhance crop productivity, driving the quest for greener alternatives over synthetic fertilizers. Cyanobacteria have been reported as a promising agricultural fertilizer, with positive effects on crop yield. However, little is known about its potential effects on the produced vegetables' nutritional quality. Studies have documented that exposure of plants to cyanobacterial crude extracts stimulates the production of enzymatic and non-enzymatic antioxidants. Vitamin C, a non-enzymatic antioxidant, plays a crucial role in protecting cells from oxidative stress and spinach is known to be relatively high in vitamin C compared to other vegetables. The purpose of this study was to determine the content of vitamin C in spinach plants grown under the use of cyanobacterial biomass as fertilizer. Spinach plants were tested in soil, under six different conditions: (i) control, (ii) commercial chemical fertilizer, cyanobacterial biomass (iii) non-cyanotoxin producer, and cyanotoxin producer of (iv) Anatoxina (ANA), (v) Microcystin (MC), and (vi) Cylindrospermopsin (CYN). The analysis of vitamin C in spinach plants was performed according to EN 14130:2003. The results showed an increased content of vitamin C in all exposed groups when compared to the control (37 mg/Kg), with statistical differences in the conditions exposed to MC (56 mg/kg), ANA (76 mg/kg), and CYN (114 mg/kg). The results suggest that the rise in vitamin C may be related to a plant defence mechanism against oxidative stress potentially generated by exposure to cyanotoxins. Although the antioxidant content in spinach plants can be enhanced as a mechanism to cope with oxidative stress, prolonged exposure may increase plants' susceptibility to accumulate cyanotoxins, which may pose a risk to human health. Additional studies are needed to understand all the positive and negative effects of using cyanobacteria biomass as a biofertilizer.
- Development of a stable melanoma dual reporter cell line expressing Luciferase and GFPPublication . Aguiar, Gonçalo; Torres, Sílvia; Prudêncio, Cristina; Soares, Raquel; Coelho, Pedro; Prudêncio, Cristina; Coelho, PedroMelanoma is the most aggressive and lethal form of skin cancer, with a high risk of metastatic spread. Obesity is recognized as a risk factor for various types of cancer. However, regarding melanoma, this association remains controversial. Obesity might act as a double-edged sword in melanoma, promoting primary tumour growth but at the same time limiting metastatic spread - the "obesity paradox”. Herein, we aimed to create a stable murine B16F10 melanoma cell line expressing both firefly luciferase (Luc) and green fluorescent protein (GFP), which will later be engrafted into diet induced-obesity animal model for future in vivo studies. B16F10-Luc-GFP cells were generated by transfection with premade lentiviral particles, featuring a construct with Luc and GFP under a cytomegalovirus promoter and mediated by a F2A element. The antibiotic selection marker (puromycin) is expressed under a Rous sarcoma virus promoter. Afterwards, the transfected cells were selected with 1 μg/ml of puromycin. The clones with the highest levels of GFP-positive cells and GFP fluorescence were purified by two rounds of cell sorting and submitted to fluorescence and bioluminescence quantification, morphology, injury, BrdU incorporation, 7-AAD, and PI cell cycle assays and compared to the parental cell line. B16F10-Luc-GFP were successfully generated, and both GFP fluorescence and D-luciferin bioluminescence are present and proportional to cell density. As expected, the parental cell line didn’t display GFP or Luc activities. Moreover, transduced cells exhibit similar morphology, motility, proliferation, viability, and cell cycle progression as B16F10 cells. Conclusions: Altogether, the future engraftment of B16F10-LucGFP in obese mice, will improve melanoma research models, enabling the in vivo and ex vivo visualization of primary tumours and metastasis, providing a better understanding of the underlying molecular mechanisms, to clarify the “obesity paradox” in melanoma.