Browsing by Issue Date, starting with "2023-04"
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- In vitro antibacterial and cytotoxic activity of Laurobasidium lauri extractsPublication . Silva, L.; Oliveira, Ana Isabel; Moreira, Fernando; Ferraz Oliveira, Rita; Pinho, CláudiaPlants and mushrooms have been used as medicines for many years, as a source of antibi-otics, antineoplastics, among others. Research have been conducted on the medicinal uses of Portu-guese plants, however, the therapeutic potentials of some of these plants used in traditional medicine, has remained unexploited. This study aims to evaluate antibacterial and cytotoxic activities, in vitro, of Laurobasidium lauri, a well-known fungus used in folk medicine on Madeira Island. An experimental study was performed using two extracts (aqueous and ethanolic 55% (V/V)) of the fun-gus isolated and in combination with three medicinal plants (Parietaria judaica, Polygonum aviculare, and Peperomia galioides). The antibacterial activity was evaluated against Escherichia coliand Staphy-lococcus aureus, through disc diffusion and broth microdilution methods. Cytotoxicity was evaluated using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Regarding the disc diffusion method E. coliwas not susceptible to any of the extracts, except for the antibiotic (41.0 ± 1.0 mm). However,S. aureus, when subjected to 10 mg/ml of the ethanolic extracts of L. lauri(isolated and in combination) exhibited an inhibition with a diameter of 16,3 ± 2,5 mm and 12,0 ± 1,7 mm, respec-tively, when compared to the control, ciprofloxacin (24,0±1,0 mm). Also, the ethanolic extract of the isolated fungus had the best value of minimum inhibitory concentration (MIC) for S. aureus(MIC = 0.078125 mg/mL). The ethanolic extract of the fungus in combination with medicinal plants showed greater cytotoxic action on lung cancer cells A549 (IC50 = 48.3±1.0 μg/mL). The fungus presented cytotoxic and antibacterial potential, and the results observed may be related to some bioactive compounds (e.g., costunolide and dehydrocostuslactone, two natural sesquiterpene lactones present in Laurustrees, where the fungus grows). However, more research is needed to confirm these biological activities and mechanisms of action.
- Nasal colonization by Staphylococcus aureusin Health Sciences students and analysis of risk fac-tors under a One Health perspectivePublication . Gomes-Sampaio, L. M.; Cláudia-Ferreira, A.; Prata, J. C.; Azevedo, R. M. S.; Pacheco, P.; Campos, Carla; Novais, C.; Peixe, L.; Dinis-Oliveira, R. J.; Coelho, C.; Miranda, C.; Quinteira, S.; Freitas, A. R.Staphylococcus aureusis the leading bacterial cause of death globally. Nasal carriage of S. aureusincreases the risk of invasive infections, including by methicillin-resistant S. aureus(MRSA) strains, but studies including Portuguese university students (PUS) are scarce. To analyse the prevalence of methicillin-susceptible S. aureus(MSSA) and MRSA among PUS enrolled in different courses/years (1st-4th) at IUCS-CESPU, characterize their antibiotic resistance profiles, and assess the potential risk factors. Swabs collected during March-December 2022 from anterior nares of 156 volunteers (median 22-years) were processed in mannitol-salt agar and, in parallel, enriched in brain-heart broth with NaCl 6.5% further plated onto ChromID® MRSA SMART. Typical colonies were stored for species identification (MALDITOF-MS) and antibiotic susceptibility testing (disk diffusion; EU-CAST/CLSI guidelines). Each student completed a questionnaire comprising demographic/clinical/social parameters. Statistical analysis was conducted in IBM-SPSS Statistics 26 using binary logistic regression applying a backward stepwise (likelihood ratio) method, with α=0.05, selecting variables using Chi-square tests and Mann-Whitney U tests for which p≤0.20, >10 occurrences, not biologicallycorrelated. Prevalence of MSSA and MRSA (cefoxitin screening) were 28.8% and 1.9%, respectively. From the 45 positive samples, 9% were multidrug-resistant, 38% were resistant to penicillin, 40% to erythromycin, 40% to clindamycin (inducible),7% to cefoxitin, 2% to tetracycline, and 2% to rifampicin. Self-reported frequent contact with animals (OR=3.44, CI 95%: 1.10–10.66) were positively associated with S. aureus, while regular sports participation presented a negative association (OR=0.36, CI 95%: 0.17–0.77). Sports participation was not correlated with self-reported excellent health (χ2=0.680, p=0.409). This is one of the first studies assessing MSSA/MRSA rates in PUS after the COVID-19 pandemics imposing higher self-protection/hygienization. While PUS-MSSA rates are similar to that previously observed, PUS-MRSA rates are slightly higher. Additional samples are being processed to explore future trends and other potential One Health factors influencing MSSA/MRSA colonization.
- Is there a link between NRF2 and depression?Publication . Santos, Marlene; Fonseca, Débora; Caldevilla, Renato; Barroso, M. Fátima; Cruz, AgostinhoDepression is a common mental health disorder that affects millions of people worldwide. Recent studies have highlighted the role of oxidative stress and inflammation in the pathogenesis of depression. NRF2 is a transcription factor that plays a crucial role in cellular defense against oxidative stress by binding to antioxidant response elements (AREs) located in the promoter region of various phase II antioxidant enzymes and stress-responsive enzymes. Decreased Keap1-Nrf2 signaling has been implicated in the development of mood disorders, such as Major Depressive Disorder. Therefore, this review aims to evaluate the in vitro and in vivo evidence of the involvement of Nrf2 in depression. A review was conducted on the PubMed database for articles published until March 8, 2022 Papers that evaluated NRF2 in animals and/or cell lines with depression and were published in English were included in the review. Studies that addressed other diseases/topics, systematic reviews, and those that did not address NRF2 were excluded. Quality assessment was performed according to Koch et al., 2022. Out of the 203 possibly relevant abstracts found through the PubMed search, 45 papers were included in the review. The results suggest that Nrf2 levels tend to decrease in animals exposed to oxidative stress or depressive behavior. When animals were treated with antidepressants or anti-inflammatory drugs, Nrf2 levels increased. Additionally, the study found that IL-10 and BDNF were key elements that were positively influenced by Nrf2 levels, protecting against oxidative stress through Keap1/Nrf2. The findings suggest that Nrf2 activation may play a crucial role in controlling oxidative stress and inflammation during depression. Furthermore, it provides evidence of the involvement of Nrf2 in depression and highlights its potential as a therapeutic target. However, further studies on clinical samples are necessary to evaluate NRF2’s putative effect in depression and antidepressant response.
- High occurrence of multidrug-resistant Esche-richia colifrom Holstein-Friesian cattle in Northern Portugal: a One Health challengePublication . Quinteira, S.; Dias, A.B.; Pinho, L.; Brito, N.V.; Campos, Carla; Freitas, A.R.; Miranda, C.Escherichia coli is currently a leading pathogen for deaths associated with antimicrobial resistance (AMR). AMR related to food-producing animals is a public health risk requiring a One Health approach. Animals are major reservoirs of antibiotic resistant E. coli which can easily reach humans through the food chain, direct contact, or the environment. To analyze the AMR profiles of E. coli in fecal samples from Holstein-Friesian cattle, as information on AMR from dairy farming in Portugal is scarce. Samples (n=112) collected from 7 different farms at Northern Portugal were pooled during February-March 2023 based on age group (8 calves and 8 cows per farm). Characteristic E. coli colonies were selected from MacConkey Agar supplemented with or without antibiotics (4 µg/ml cefotaxime; 3 µg/ml colistin), for confirmation by MALDI-TOF mass spectrometry and antimicrobial susceptibility testing (AST), according to EUCAST/CLSI guidelines. ESBL phenotype were searched using the Double-Disk Synergy Test. Presumptive E. coli isolates (n=110) representing different farming production systems were obtained and 51 representatives were identified by MALDI-TOF and tested by AST. From both calves and cows, 95% and 63% of the E. coli isolates exhibited resistance to ≥1 antimicrobial classes and multidrug resistance (MDR, resistance to ≥3 antimicrobial classes), respectively. Isolates were mostly resistant to gentamycin (88%), ampicillin (72%), amoxicillin plus clavulanic acid (63%), tetracycline (63%) and cefotaxime (53%). Only two isolates showed susceptibility two all tested antibiotics. ESBL activity was observed in 21% of E. coli isolates. All analyzed pools were classified as MDR. This is one of the first studies on AMR rates of E. coli from dairy cattle in Northern Portugal. It reveals a high prevalence of MDR E. coli, which is a worrying finding and emphasize the need of a multisectoral One Health approach to minimize its impact.
- Candidatura de obtenção do Título de Especialista DEVISINGPublication . Binyon, Claire MargaretIn this report, presented as part of my application for the title of Specialist in Devising/Theatre it is my intention to follow the course of my professional life and its connection with Devising and the development of this methodology as an approach to theatre making. Along the way I will evidence my level of expertise and knowledge in this area and as such show my eligibility for the specialist status, including the presentation of the working booklet 10 years of a module in Devising for actors. [...]
- As Relações Públicas e a Gestão da Comunicação de Crise numa IESPublication . Pinto, Susana Mónica da CruzEste trabalho profissional explora o papel e a importância da definição de uma estratégia de gestão e comunicação de crise para uma instituição de ensino superior, o Instituto Superior de Contabilidade e Administração do Porto (ISCAP), através da criação do Manual de Crise do ISCAP. A comunicação de crise é uma das áreas de atuação das relações públicas estratégicas, fundamental para a preservação de uma imagem e reputação organizacional positiva, bem como o normal funcionamento da organização. Nos dias de hoje, as organizações vivem um conjunto de desafios relacionados com a nova sociedade de informação e o consequente desenvolvimento das redes sociais. Com o desenvolvimento de diversas plataformas digitais que criam diálogos entre a empresa-público e público-público, existe um maior risco para o surgimento e a proliferação de incidentes e mensagens negativas que podem afetar a credibilidade e a reputação da organização. Neste trabalho apresenta-se, na primeira parte, a contextualização teórica de relações públicas e de comunicação de crise, com o principal objetivo de entender o seu papel e os modelos a utilizar, com o intuito de preservar a imagem e reputação organizacional. Na segunda parte, após a apresentação da instituição e da análise histórica do impacto das crises em que esteve envolvida, apresenta-se o trabalho de natureza profissional, onde tendo em conta o plano de gestão e comunicação de crise, se concebe o Manual de Crise do ISCAP, e se definem estratégias para a sua implementação e disseminação.
- The effect of Mo2C additions on the oxidation resistance of (Ti,W)CN cermets as base material for the production of cutting toolsPublication . Hadi, Morteza; Rafiaei, Seyed Mahdi; Fernandes, FilipeThe effect of Mo2C secondary carbide on the oxidation resistance of (Ti0.93W0.07)CN0.3-20%Ni cermet was investigated using DSC-TG, isothermal oxidation, XRD, and SEM/EDS characterisations. Adding Mo2C secondary carbides to (Ti, W)CN cermets is one of the methods used for improving their mechanical properties. However, Mo2C secondary carbides bring a detrimental effect to oxidation resistance. The isothermal oxidation results of the samples at 750 ◦C possessing 0% and 2% MO2C follow the parabolic law, while in the samples containing 5% and 8% Mo2C, the rate of oxidation and the spallation of the oxide scale increased significantly. The thickness of the oxide layer in the cermet containing 5% of Mo2C increased three times, whereas the mass per unit area of the detached oxides in the 8% Mo2C specimen dramatically increased up to 100 times. The investigations revealed that the increase in the amount of W and Mo on the cermet material, as well as the formation of a multi-zone oxide layer, are the main reasons for oxide phase propagation.
- Does body mass index infuence surgical options and overall survival in breast cancer patients?Publication . Luís, Carla ; Fernandes, Rute ; Dias, João ; Pereira, Deolinda ; Machado, Firmino ; Baylina, Pilar; Fernandes, Rúben ; Soares, RaquelObesity is a relevant risk factor in breast cancer (BC), but little is known about the efects of overweight and obesity in surgical outcomes of BC patients. The aim of this study is to analyse surgical options and associated overall survival (OS) in overweight and obese women with BC. In this study, 2143 women diagnosed between 2012 and 2016 at the Portuguese Oncology Institute of Porto (IPO-Porto) were included, and the clinicopathological information was retrieved from the institutional database. Patients were stratifed by body mass index (BMI). Statistical analysis included Pearson's chi-squared test with statistical signifcance set at p
- The impact of BDNF, NTRK2, NGFR, CREB1, GSK3B, AKT, MAPK1, MTOR, PTEN, ARC, and SYN1 genetic polymorphisms in antidepressant treatment response phenotypesPublication . Santos, Marlene; Lima, Luis; Carvalho, Serafim; Mota-Pereira, Jorge; Pimentel, Paulo; Maia, Dulce; Correia, Diana; Barroso, M. Fátima; Gomes, Sofia; Cruz, Agostinho; Medeiros, RuiThis study aimed to investigate the influence of genetic variants in neuroplasticity-related genes on antidepressant treatment phenotypes. The BDNF-TrkB signaling pathway, as well as the downstream kinases Akt and ERK and the mTOR pathway, have been implicated in depression and neuroplasticity. However, clinicians still struggle with the unpredictability of antidepressant responses in depressed patients. We genotyped 26 polymorphisms in BDNF, NTRK2, NGFR, CREB1, GSK3B, AKT, MAPK1, MTOR, PTEN, ARC, and SYN1 in 80 patients with major depressive disorder treated according to the Texas Medical Algorithm for 27 months at Hospital Magalhães Lemos, Porto, Portugal. Our results showed that BDNF rs6265, PTEN rs12569998, and SYN1 rs1142636 SNP were associated with treatment-resistant depression (TRD). Additionally, MAPK1 rs6928 and GSK3B rs6438552 gene polymorphisms were associated with relapse. Moreover, we found a link between the rs6928 MAPK1 polymorphism and time to relapse. These findings suggest that the BDNF, PTEN, and SYN1 genes may play a role in the development of TRD, while MAPK1 and GSK3B may be associated with relapse. GO analysis revealed enrichment in synaptic and trans-synaptic transmission pathways and glutamate receptor activity with TRD-associated genes. Genetic variants in these genes could potentially be incorporated into predictive models of antidepressant response.
- Influence of the alloying elements on the tribological performance of DLC coatings in different sliding conditionsPublication . Evaristo, Manuel; Fernandes, Filipe; Cavaleiro, AlbanoReduction of friction and wear at the sliding surfaces are the main concern in several applications. From an extensive list of low friction hard coatings, DLC type is one of the most studied and develop for achieving low wear and friction. The addition of an alloying element is extensively used, since it can change significantly the coatings performance. Therefore, in this research the tribological behaviour of DLC coatings alloyed with different elements was evaluated, since no works comparing the tribological properties of DLC films with approximately the same alloying elements concentration are reported in the literature. The coatings were deposited by physical vapor deposition and alloyed with: tungsten (W), silver (Ag), silicon (Si), silicon and oxygen (SiO), with concentrations of metallic elements between 10 and 15 at. % and a pure DLC coating was also deposited for comparison purposes. The coatings hardness varied between 23 GPa for the pure DLC and 11 GPa for the alloyed with Si and O. The tribological behaviour of the coatings was evaluated by pin-on-disk against 10 mm 100Cr6 steel balls, at room temperature (RT) and 100 ◦C. The best wear resistance was achieved with the pure DLC and DLC-W for RT tests. At RT the lowest friction was obtained with the DLCSi and DLCSiO coatings. Despite of the low COF values, those coatings displayed the highest specific wear rate values among all the films. This is attributed to the presence of hard SiC particles stick at the ball counterpart which promotes severe abrasion of the coatings surface. The increase of the temperature to 100 ◦C increases significantly the friction coefficient for the DLC and DLC-W coatings, whilst, for DLC-Ag, DLC-Si and DLC-SiO coatings a slight decrease is noticed. At this temperature DLCAg coating is the more performing due to the formation of a tick tribolayer rich in Ag adhered at the counterpart surface. With this work it was concluded that friction and wear are not directly related, and the third bodies formed on the sliding surfaces have major influence on the tribological performance of the system.
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