Percorrer por autor "Fernandes, Laura"
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- Clonal and plasmid-mediated dissemination of mcr-1 in Escherichia coli strains at the human–companion animal interface : genomic characterisation of colistin resistance plasmidsPublication . Menezes, Juliana; Silva, Joana Moreira da; Fernandes, Laura; Amaral, Andreia J.; Pomba, ConstançaThe global emergence of plasmid-mediated colistin resistance (mcr-1) gene poses a critical threat to human and animal health due to its ability for horizontal dissemination. While the role of food-producing animals is well recognised, the contribution of companion animals and household environments to the persistence and circulation of mcr-1 remains poorly understood. In this study, we investigated the genetic relatedness of mcr-1-positive Escherichia coli strains and their associated plasmids from dogs and their cohabiting humans in Portugal (2018–2020). Whole-genome sequencing, was performed on 17 strains, including repeated sampling from the same hosts over time. Core genome SNP analysis revealed clonal relatedness among several strains from the same host and between household members (≤6 SNPs). A total of 14 mcr-1-harbouring plasmids were identified and classified into three major incompatibility groups: IncX4 (n = 2), IncHI2 (n = 5), and IncI2 (n = 7). IncX4 plasmids were detected in clonally related strains from the same human host and were identical, indicating maintenance within a persistent lineage. A subset of IncI2 plasmids formed a closely related cluster (1–6 SNPs) across genetically distinct hosts, supporting the possibility of horizontal dissemination. IncHI2 plasmids displayed greater structural diversity and carried multiple antimicrobial and metal resistance determinants. Notably, chromosomal integration of mcr-1 was identified in three strains, suggesting a potential pathway for stabilistion of colistin resistance. Overall, these findings highlight the combined role of clonal expansion and plasmid circulation in shaping the epidemiology of mcr-1 genes in community settings, reinforcing the importance of genomic surveillance within a One Health framework.
- Monitoring antimicrobial resistance trends and emerging carbapenemases in Enterobacterales causing companion animal infections : a four-year studyPublication . Fernandes, Laura; Silva, Joana Moreira da; Menezes, Juliana; Marques, Cátia; Caneiras, Cátia; Pomba, ConstançaThis study assessed longitudinal trends in antimicrobial resistance (AMR) among Enterobacterales causing companion animal infections in Portugal between 2020 and 2023 and characterized carbapenemase-producing Enterobacterales (CPE). A collection of 4155 non-duplicate clinical Enterobacterales isolates underwent antimicrobial susceptibility testing mainly through disk diffusion, targeting β-lactams, fluoroquinolones, aminoglycosides and folate pathway inhibitors. Possible bacteria-AMR associations and temporal trends were statistically assessed. Potential CPE were selected on Brilliance™ CRE Agar, confirmed by multiplex PCR and characterized by whole-genome sequencing (Illumina NovaSeq). In silico MLST was performed and the clonality of the strains was evaluated through maximum likelihood phylogenetic trees and pairwise SNP matrixes. Klebsiella spp. and Enterobacter spp. exhibited a higher likelihood of AMR than Escherichia coli (P < 0.001, ORs between 2.56 and 14.32). Most AMR phenotypes remained stable or declined over time, although fluoroquinolone resistance increased toward the end of the study period. Eighteen CPE mostly associated with high-risk global STs (E. coli ST410 and ST457, Klebsiella pneumoniae ST11, ST147 and ST307, respectively) were detected, carrying blaKPC-3, blaNDM-5, blaOXA-181 or blaOXA-244. Genomic analysis showed four CPE strain pairs from epidemiologically unrelated sources had < 10 SNPs differences, indicating possible recent clonal transmission of E. coli ST4981 and K. pneumoniae ST147 and ST273 strains. Overall, this study presents longitudinal AMR surveillance data from companion animal Enterobacterales infections and characterizes the genetic diversity of CPE, having detected international high-risk clones and possible transmission events. These findings reinforce the importance of integrating companion animals into One Health surveillance systems and antimicrobial stewardship strategies.
- PROPOSTA DE REQUALIFICAÇÃO NA ÁREA ENVOLVENTE AO PALÁCIO DO FREIXOPublication . Fernandes, Laura; Flores, JoaquimA presente memória de projeto tem o intuito de proporcionar uma base de pesquisas e análises a respeito da zona do Freixo, em Campanhã, que nortearão propostas de intervenções requalificadoras no contexto urbano que objetivem a melhoria dos espaços públicos bem como a articulação do sítio com as zonas adjacentes. A memória de projeto será dividida em 4 capítulos que abordarão, em sequência, o processo de evolução urbana do Freixo, que será baseado em análises cartográficas no decorrer dos anos e em leituras informativas a respeito do tema; o diagnóstico da situação atual do Freixo, abordado a partir da elaboração de mapas que sintetizarão as características principais do sítio e que posteriormente serão relacionadas com as intenções do Plano Diretor Municipal vigente da cidade do Porto e com o Masterplan Estratégico da Zona Oriental do Porto; a busca de referenciais contemporâneos de projeto que solucionem questões similares às questões identificadas no capítulo diagnóstico; a definição de diretrizes e o lançamento de 9 projetos de requalificação no Freixo articulados e complementares entre si, explorando as características identificadas e inspirado nos referenciais de projeto apontados.