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- Disclosing the antifungal mechanisms of the Cyclam Salt H4[H2(4-CF3PhCH2)2Cyclam]Cl4 against Candida albicans and Candida kruseiPublication . Costa, Inês; Lopes, Inês; Morais, Mariana; Silva, Renata; Remião, Fernando; Medeiros, Rui; Alves, Luís G.; Pinto, Eugénia; Cerqueira, FátimaMycoses are one of the major causes of morbidity/mortality among immunocompromised individuals. Considering the importance of these infections, the World Health Organization (WHO) defined a priority list of fungi for health in 2022 that include Candida albicans as belonging to the critical priority group and Pichia kudriavzevii (Candida krusei) to the medium priority group. The existence of few available antifungal drugs, their high toxicity, the acquired fungal resistance, and the appearance of new species with a broader spectrum of resistance, points out the need for searching for new antifungals, preferably with new and multiple mechanisms of action. The cyclam salt H4[H2(4-CF3PhCH2)2Cyclam]Cl4 was previously tested against several fungi and revealed an interesting activity, with minimal inhibitory concentration (MIC) values of 8 µg/mL for C. krusei and of 128 µg/mL for C. albicans. The main objective of the present work was to deeply understand the mechanisms involved in its antifungal activity. The effects of the cyclam salt on yeast metabolic viability (resazurin reduction assay), yeast mitochondrial function (JC-1 probe), production of reactive oxygen species (DCFH-DA probe) and on intracellular ATP levels (luciferin/luciferase assay) were evaluated. H4[H2(4-CF3PhCH2)2Cyclam]Cl4 induced a significant decrease in the metabolic activity of both C. albicans and C. krusei, an increase in Reactive Oxygen Species (ROS) production, and an impaired mitochondrial function. The latter was observed by the depolarization of the mitochondrial membrane and decrease in ATP intracellular levels, mechanisms that seems to be involved in the antifungal activity of H4[H2(4-CF3PhCH2)2Cyclam]Cl4. The interference of the cyclam salt with human cells revealed a CC50 value against HEK-293 embryonic kidney cells of 1.1 μg/mL and a HC10 value against human red blood cells of 0.8 μg/mL.
- Dairy cattle and the iconic autochthonous cattle in northern Portugal are reservoirs of multidrug-resistant Escherichia coliPublication . Quinteira, Sandra; Dantas, Rui; Pinho, Luís; Campos, Carla; Freitas, Ana R.; Brito, Nuno V.; Miranda, Carla; Campos, CarlaAnimals destined for human consumption play a key role in potentially transmitting bacteria carrying antibiotic resistance genes. However, there is limited knowledge about the carriage of antibiotic-resistant bacteria in native breeds. We aimed to characterize the phenotypic profiles and antibiotic resistance genes in Escherichia coli isolated from bovines, including three native Portuguese bovine breeds. Forty-nine E. coli isolates were selected from 640 fecal samples pooled by age group (eight adult or eight calf samples) from each farm, representing both dairy cattle raised in intensive systems and meat cattle raised in extensive systems in Northern Portugal. The presumptive E. coli colonies plated onto MacConkey agar were confirmed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The antibiotic resistance profiles were screened by antimicrobial susceptibility testing (EUCAST/CLSI guidelines), and the antibiotic resistance genes by PCR. Most isolates showed resistance to ampicillin (69%), tetracycline (57%), gentamicin (55%), and trimethoprim + sulfamethoxazole (53%), with no resistance to imipenem. Resistance to at least one antibiotic was found in 92% of isolates, while 59% exhibited multidrug resistance. Most calf isolates, including those from native breeds, showed a multidrug-resistant phenotype. Among the adults, this was only observed in Holstein-Friesian and Barrosã cattle. None of the Holstein-Friesian isolates were susceptible to all the tested antibiotics. ESBL-producing E. coli was identified in 39% of isolates, including those from Holstein-Friesian calves and adults, Cachena calves and Minhota adults. The sul2 gene was detected in 69% of isolates, followed by blaCTX-M (45%), aac(3′)-IV (41%), and aac(6′)-Ib-cr (31%), with a higher prevalence in adults. This pioneering study highlights the concerning presence of multidrug-resistant E. coli in native Portuguese cattle breeds.
- A cyclam salt as an antifungal agent: Interference with Candida spp. and Cryptococcus neoformans mechanisms of virulencePublication . Cerqueira, Fátima; Medeiros, Rui; Lopes, Inês; Campos, Carla; Ferraz, Maria Pia; Silva, Fernando; Alves, Luís G.; Pinto, EugéniaThe importance of fungal infections, particularly those caused by yeasts, is increasing among the medical community. Candida albicans and Cryptococcus neoformans are amongst the high-priority fungal species identified by the World Health Organization (WHO) and are considered in the critical group, while Candida krusei is included in the medium-priority group. The cyclam salt H4[H2(4-CF3PhCH2)2Cyclam]Cl4 proved to be active against the growth of these three yeasts, and the aim of this work was to verify its interference with their virulence mechanisms, whether shared or unique. H4[H2(4-CF3PhCH2)2Cyclam]Cl4 significantly inhibited biofilm production and catalase activity, being able to interfere with C. albicans dimorphic transition and C. neoformans melanin production. At the minimal inhibitory concentration (MIC) values, H4[H2(4-CF3PhCH2)2Cyclam]Cl4 had no antioxidant effect, as determined by the DPPH method. When using the RAW264.7 macrophage cell line, H4[H2(4-CF3PhCH2)2Cyclam]Cl4 reduced nitric oxide (NO) detection (the Griess reaction), but this effect was associated with a significant toxic effect on the cells.
- Atividade atípica do Vírus Sincicial Respiratório durante a pandemia de COVID-19 num hospital portuguêsPublication . Oliveira, Márcia; Martins, Nádia; Mota, Sandra; Sousa, MariaO Vírus Sincicial Respiratório (RSV) representa a principal causa de infeção aguda do trato respiratório inferior em crianças até aos 5 anos de idade. Após o início da pandemia da COVID-19 em 2020, foi necessário implementar medidas de controlo, que afetaram igualmente a atividade do RSV. Estudar o perfil epidemiológico do RSV em utentes pediátricos que recorreram ao Centro Hospitalar da Póvoa de Varzim - Vila do Conde, no período de 1 de setembro de 2019 até 31 de março de 2022. Estudou-se os resultados da pesquisa de RSV por Reação em Cadeia da Polimerase, através da consulta de registos existentes no SISLAB®. A sua sistematização realizou-se no IBM SPSS Statistics 28. A atividade do RSV na época sazonal de 2019/2020 iniciou na semana 49 de 2019 e terminou na semana 11 de 2020. Na época sazonal de 2020/2021 não se registaram casos de infeção. Registou-se atividade do RSV da semana 24 de 2021 até à semana 3 de 2022. Entre 2019 e 2020, as crianças com idade inferior a 13 meses representaram 57,1% dos casos de infeção, e entre 2021 e 2022, 24,3%. A ausência de atividade do RSV coincidiu com a implementação de medidas de controlo da COVID-19. O surto inter-sazonal registou-se após a flexibilização das mesmas, observando-se assim um perfil epidemiológico do RSV diferente do habitualmente registado em Portugal.
- A meta-analysis on the role of sonication in the diagnosis of cardiac implantable electronic device-related infectionsPublication . Araújo, Daniela; Martins, João P.; Ferreira, Stephanie; Mota, Sandra; Ferreira, Pedro L. ; Pimenta, RuiOne of the biggest obstacles in diagnosing Implant-Associated Infections is the lack of infection criteria and standardized diagnostic methods. These infections present a wide range of symptoms, and their diagnosis can be hampered by the formation of microbial biofilms on the surface of implants. This study aimed to provide insight into the performance of sonication in the diagnosis of infections associated with Cardiac Implantable Electronic Devices, to help define a consensus on the algorithm for the microbial diagnosis of these infections. We carried out a systematic review with meta-analysis. The PRISMA methodology guidelines were followed, and an advanced search was carried out in PubMed and Web of Science, which enabled 8 articles to be included in the review, in which a meta-analysis was also carried out. QUADAS-2 was used to assess the risk of bias and effect measures were calculated to assess publication bias. The overall sensitivity of the method was 0.823 (95% CI: 0.682–0.910) and the specificity was 0.632 (95% CI: 0.506–0.743). These results suggest that sonication may offer advantages in diagnosing these infections. However, it is essential to approach these findings carefully and take into account the recommendations provided in the EHRA 2019 guidelines. This study highlights the importance of more effective diagnostic approaches for implantable medical device-associated infections to improve the quality of treatment and minimize the risks associated with these challenging medical conditions.
- New CTX-M group conferring β-Lactam resistance: A compendium of phylogenetic insights from biochemical, molecular, and structural biologyPublication . Mendonça, Jacinta; Guedes, Carla; Silva, Carina; Sá, Sara; Oliveira, Marco; Accioly, Gustavo; Baylina, Pilar; Barata, Pedro; Pereira, Cláudia; Fernandes, RubenThe production of extended-spectrum β-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of dissemination in different epidemiological contexts. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants distributed in several sublineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular, and structural point of view through homology in amino acid sequences. Our data, combined with described literature, provide phylogenetic and structural evidence of a new group. Thus, herein, we propose six groups among CTX-M enzymes: the already stablished CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, and CTX-M-25 clusters, as well as CTX-M-151 as the new cluster.
- Neuron–microglia contact-dependent mechanisms attenuate methamphetamine-induced microglia reactivity and enhance neuronal plasticityPublication . Bravo, Joana; Ribeiro, Inês; Terceiro, Ana Filipa; Andrade, Elva B.; Portugal, Camila Cabral; Lopes, Igor M.; Azevedo, Maria M.; Sousa, Mafalda; Lopes, Cátia D. F.; Lobo, Andrea C.; Canedo, Teresa; Relvas, João Bettencourt; Summavielle, TeresaExposure to methamphetamine (Meth) has been classically associated with damage to neuronal terminals. However, it is now becoming clear that addiction may also result from the interplay between glial cells and neurons. Recently, we demonstrated that binge Meth administration promotes microgliosis and microglia pro-inflammation via astrocytic glutamate release in a TNF/IP3R2-Ca2+-dependent manner. Here, we investigated the contribution of neuronal cells to this process. As the crosstalk between microglia and neurons may occur by contact-dependent and/or contact-independent mechanisms, we developed co-cultures of primary neurons and microglia in microfluidic devices to investigate how their interaction affects Meth-induced microglia activation. Our results show that neurons exposed to Meth do not activate microglia in a cell-autonomous way but require astrocyte mediation. Importantly, we found that neurons can partially prevent Meth-induced microglia activation via astrocytes, which seems to be achieved by increasing arginase 1 expression and strengthening the CD200/CD200r pathway. We also observed an increase in synaptic individual area, as determined by co-localization of pre- and post-synaptic markers. The present study provides evidence that contact-dependent mechanisms between neurons and microglia can attenuate pro-inflammatory events such as Meth-induced microglia activation.
- The perspectives of current health professionals regarding their interaction with specific technologyPublication . Amorim, Manuela; Mota, Sandra; Tavares, DianaTechnological evolution in healthcare has been continuous. To access the advantages and disadvantages of professional-machine interaction from the user's perspective in health professionals we developed an online questionnaire. A total of 107 responses were obtained from 12 health technologies areas, showing some differences between them. The majority are 5 to 10 years of experience (28.0%). Speed, safety and efficiency stands out as benefits and dehumanization of the care provided and the reduction of jobs as risks. The user's perspective contributes in an elementary way to the current and future industry in the health area, and therefore should not be neglected.
- Microbiological evaluation of swimming pool water at hotel unitsPublication . Ferreira, Stéphanie; Amorim, Manuela; Moreira, Teresa; Araújo, António; Mota, SandraThe swimming pools are currently operated by public and private entities for the development of sports, recreational and therapeutic activities. Therefore, it is essential to guarantee the quality of the pool water, as they can be the cause of various pathologies. The objective of this work was to analyze the data from the microbiological evaluation of the water in the indoor and outdoor pools of hotels in mainland Portugal and Madeira in 2016, in order to verify the quality of the water.
- Swimming pool water quality in the northern zone of PortugalPublication . Ferreira, Stephanie; Amorim, Manuela; Araújo, António; Mota, SandraThe use of swimming pools for recreational purposes is associated with several benefits for the health and wellbeing of its users, however it is necessary to monitor the quality of the water in terms of public health. With the aim of evaluating the microbiological quality of swimming pool water, the results of 1280 water samples from swimming pools in the North of Portugal were analyzed. The evaluation of the water quality was carried out through the research and quantification of microorganisms viable at 37ºC, Coliform Bacteria, Enterococci, Escherichia coli, Pseudomonas aeruginosa, Coagulase Positive Staphylococci and the Total Number of Staphylococci.
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