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- Effectiveness of the 2023 Autumn XBB.1.5 COVID-19 Booster During Summer 2024 in the EU/EEA: A VEBIS Electronic Health Record Network StudyPublication . Humphreys, James; Nicolay, Nathalie; Braeye, Toon; Van Evercooren, Izaak; Hansen, Christian Holm; Moustsen-Helms, Ida Rask; Sacco, Chiara; Fabiani, Massimo; Castilla, Jesús; Martinez-Baz, Ivan; Machado, Ausenda; Soares, Patricia; Ljung, Rickard; Pihlstrom, Nicklas; Kissling, Esther; Nardone, Anthony; Monge, Susana; Bacci, Sabrina; Nunes, Baltazar; VEBIS-EHR Working GroupBackground: After a period of low SARS- CoV-2 activity, viral circulation increased in Europe from May 2024, driven byimmune-evasive KP sublineages of the JN.1 variant. We estimated vaccine effectiveness (VE) of the XBB.1.5 dose administeredin autumn 2023 against COVID-19-related hospitalisations and deaths in individuals 65 years of age or older during this period. Methods: We conducted a multi-country cohort study across six EU nations in the VEBIS-EHR network using linked electronichealth records. VE against COVID-19-related hospitalisation and death during June–August 2024 was estimated using Cox re-gression in a two-stage analysis, adjusting for demographics, comorbidities and prior vaccination history. Results: Among individuals 65–79 and ≥ 80 years old, respectively, VE of the XBB.1.5 dose ≥ 6 months post administration was13% (95% CI: −12% to 33%) and 7% (95% CI: −7% to 19%) against hospitalisation and 39% (95% CI: −7% to 65%) and 3% (95% CI:−23% to 23%) against deaths. Conclusions: XBB.1.5 vaccination provided minimal residual protection against severe COVID-19 outcomes among adults aged≥ 65 years more than 6 months after vaccination, during the summer 2024 period of increased SARS- CoV-2 activity.
- 17.ª Reunião Anual PortFIR - Segurança dos Alimentos: Governança, Ciência e Novos Modelos de Produção Face aos Desafios Globais: Resumo da reuniãoPublication . Brazão, Roberto; Fernandes, Paulo; Dias, Maria da GraçaResumo da 17.ª Reunião Anual PortFIR subordinada ao tema "Segurança dos Alimentos: Governança, Ciência e Novos Modelos de Produção Face aos Desafios Globais". A publicação apresenta as comunicações e abstracts/posters submetidos, bem como os resultados da avaliação ao grau de satisfação dos participantes no evento e algumas fotos do evento.
- The influence of short-chain fatty acids on the survival and virulence of Arcobacter butzleriPublication . Fonseca, Inês M.; Mateus, Cristiana; Vieira, Alexandre; Domingues, Fernanda; Manageiro, Vera; Oleastro, Mónica; Ferreira, SusanaAims: Arcobacter butzleri, a widespread bacterium linked to gastrointestinal disease, can bypass host colonization resistance mechanisms; however, its response to short-chain fatty acids (SCFAs) remains poorly understood. This study investigated the impact of SCFAs on A. butzleri ’s survival and virulence. Methods and results: Eight A. butzleri isolates were assessed under varying concentrations of individual SCFAs and mixtures (m-SCFAs). Higher SCFAs concentrations inhibited bacterial growth in a strain-dependent manner. Transcript analysis of putative virulence genes revealed upregula- tion of ciaB and flaA across most m-SCFAs concentrations, while luxS expression increased at 90 mM. SCFAs generally reduced bacterial motility, with sodium propionate reducing motility but enhancing biofilm-forming ability in the model strain. Additionally, SCFAs exposure decreased the ability of A. butzleri to adhere to and invade the Caco-2 intestinal epithelial cell line. Whole-genome sequencing of the eight A. butzleri isolates revealed extensive genetic diversity, particularly in virulence- and stress-associated genes, although consistent genot ype/phenot ype correlations were not observed. Conclusions: Altogether, these findings demonstrate that SCFAs modulate A. butzleri survival and virulence, providing novel insights into their significance in shaping pathogen behaviour and host-pathogen interactions.
- Mpox in People Living with HIV: Clinical Challenges, Preventive Strategies and Public Health ImplicationsPublication . Cordeiro, Rita; Caria, J.; Sobral, D.; Póvoas, D.; .Monkeypox virus (MPXV) re-emerged in 2022 with a global outbreak that affected more than 100,000 individuals worldwide. People living with HIV (PLWH) accounted for a substantial proportion of cases, raising concerns about disease presentation, management, and outcomes in this population. Evidence indicates that PLWH with advanced or uncontrolled HIV infection experienced more severe mpox, with higher hospitalization rates, more complications, and longer disease courses. In contrast, individuals with well-controlled HIV generally had outcomes similar to those without HIV. Access to timely diagnosis, consistent antiretroviral therapy, and availability of tecovirimat were key factors influencing prognosis. Reports also suggest bidirectional interactions between mpox and HIV pathogenesis. Immune activation and APOBEC3-related viral evolution have been proposed; however, these mechanisms remain incompletely characterized and warrant further investigation. Moreover, disparities in healthcare access and stigma compound the vulnerability of PLWH, emphasizing the need for integrated approaches.
- An engineered U1 snRNA-based therapeutic approach can efficiently rescue a 5’ splice site mutation causing Mucolipidosis type IIIPublication . Peretto, L.; Gonçalves, M.; Santos, J.I.; Duarte, A.J.; Moreira, L.; Encarnação, M; Coutinho, M.F.; Pinotti, M.; Balestra, D.; Alves, S.; Matos. L.A significant number of splicing mutations have been identified in Lysosomal Storage Disorders (LSDs). Mucolipidosis III (ML III) is a LSD caused by GlcNAc-1-phosphotransferase deficiency, which impairs the trafficking of lysosomal hydrolases. 10% of the genetic defects in ML III are splicing mutations, and around 45% affect 5' splice-sites (ss) thus constituting a good target for mutation specific therapies. The use of engineered U1 snRNA (either modified U1 snRNAs or exon-specific U1s - ExSpeU1s) has been applied as a potential therapeutic strategy to correct 5’ss defects. Here we used engineered U1 snRNAs to correct the GNPTAB exon 17 skipping caused by the 5’ss mutation (c.3335+6T>G) found in a ML III patient. First, we performed transfection of exon-trapping minigenes expressing exon 17 surrounded by a portion of introns - pGNPTAB_WT and pGNPTAB_+6, in HEK293T cells to analyze if they reproduce the WT and mutant splicing patterns. Then, to evaluate the potential of 2 modified U1’s, 3 ExSpeU1s and 2 modified U6’s to restore mRNA splicing, these vectors were cotransfected into HEK293T cells along with the mutant +6 minigene as well as electroporated in patient’s fibroblasts. Then, cells were harvested, and RT-PCR analysis was performed. Both minigenes reproduced the control or ML III patient cDNA’s splicing patterns, thus, different concentrations of the modified U1’s and ExSpeU1s were tested together with the mutant minigene. The cDNA analysis showed almost 100% of exon 17 inclusion when one of the ExSpeU1s, was overexpressed in HEK293T cells. The combination of the 2 modified U6’s with the modified U1’s or the ExSpeU1s allowed exon 17 inclusion at some extent, but not as effectively as with the best ExSpeU1 alone. The electroporation of the 2 modified U1’s and of the 3 ExSpeU1s was done, and the cDNA analysis of patient’s fibroblasts treated with 2 ExSpeU1s (ExSpeU1 int17-1 or int17-2) showed around 35% and 15% of exon 17-including transcripts, respectively. To confirm these results, given that the lentiviral transduction is a more efficient delivery technique than electroporation, the gene cassettes of the 2 most promising ExSpeU1s were cloned in a lentivirus vector and after obtaining the viral mediums, their transduction in patient’s fibroblasts is being optimized. The cDNA analysis of preliminary experiments is still ongoing. In conclusion, we have developed an RNA therapy based on engineered U1 snRNAs for a ML III 5’ss mutation. We showed that an ExSpeU1 (binding downstream of the mutated 5´ss) can restore proper exon 17 definition in vitro, opening the opportunity for a personalized therapeutic intervention.
- Can an Antisense Oligonucleotide Exon Skipping Rewrite the Story of N-Acetylglucosamine-1-Phosphotransferase Deficiency?Publication . Gonçalves, M.; Moreira, L.; Encarnação, M.; Gaspar, P.; Duarte, A.J.; Santos, J.I.; Coutinho, M.F.; Prata, M.J.; Omidi, M.; Pohl, S.; Silva, F.; Oliveira, P.; Matos, L.; Alves, S.Mucolipidosis II (ML II) is a Lysosomal Storage Disorder caused by N-acetylglucosamine-1-phosphotransferase (GlcNAc-PT) deficiency, which impairs the trafficking of lysosomal hydrolases. Of all ML II mutations, c.3503_3504delTC in GNPTAB exon 19 is the most frequent, making it a good target for a personalized therapy. Here, we explored an innovative therapeutic strategy based on the use of antisense oligonucleotides (ASOs). Previously, in ML II patients’ fibroblasts, we tested ASOs to induce exon 19 skipping in pre-mRNA, successfully generating an in-frame mRNA (Matos et al., 2020). Now, our aim is to determine whether this in-frame transcript leads to increased GlcNAc-PT levels improving ML II cellular phenotype.
- An engineered U1 snRNA-based therapeutic approach can efficiently rescue a 5’ splice site mutation causing Mucolipidosis type IIIPublication . Peretto, L.; Gonçalves, M.; Santos, J.I.; Duarte, A.J.; Moreira, L.; Encarnação, M.; Coutinho, M.F.; Pinotti, M.; Balestra, D.; Alves, S.; Matos, L.A significant number of splicing mutations have been identified in Lysosomal Storage Disorders (LSDs). Mucolipidosis III (ML III) is a LSD caused by GlcNAc-1-phosphotransferase deficiency, which impairs the trafficking of lysosomal hydrolases. 10% of the genetic defects in ML III are splicing mutations, and around 45% affect 5' splice-sites (ss) thus constituting a good target for mutation specific therapies. The use of engineered U1 snRNA (either modified U1 snRNAs or exon-specific U1s - ExSpeU1s) has been applied as a potential therapeutic strategy to correct 5’ss defects. Here we used engineered U1 snRNAs to correct the GNPTAB exon 17 skipping caused by the 5’ss mutation (c.3335+6T>G) found in a ML III patient.
- Gapmer Antisense Oligonucleotides as a New Class of Genetic Substrate Reduction Agents in Mucopolysaccharidosis IIICPublication . Santos, Juliana I.; Gonçalves, Mariana; Almeida, Matilde B.; Rocha, Hugo; Duarte, Ana J.; Matos, Liliana; Moreira, Luciana V.; Encarnação, Marisa; Gaspar, Paulo; Prata, Maria J.; Coutinho, Maria F.; Alves, SandraBackground: Lysosomal storage disorders (LSDs) include over 70 rare inherited metabolic diseases caused by defective lysosomal enzymes or associated proteins, leading to the accumulation of undegraded substrates and progressive cellular dysfunction. Among these, Mucopolysaccharidoses (MPS) are a group characterized by storage of undegraded glycosaminoglycans (GAGs), including heparan, dermatan, keratan, and chondroitin sulfates. MPS type III (as known as Sanfilippo syndrome) predominantly affects the central nervous system (CNS) and manifests as severe neurodegeneration, behavioral abnormalities and cognitive decline. The subtype IIIC results from deficient activity of acetyl-CoA:α-glucosaminide N-acetyltransferase (HGSNAT) enzyme. Currently, treatment options for MPS III are limited, increasing the need to find alternative therapies. RNA-based therapies have recently gained attention as powerful alternatives to traditional treatments, with several already approved for clinical use in other diseases. Among these, antisense oligonucleotides (ASOs) stand out as a highly promising class of molecules for personalized medicine. ASOs are short, chemically synthesized strands of nucleic acids designed to bind specifically to target RNA sequences, thereby influencing gene expression. In this work, we explored the application of gapmer ASOs as a genetic substrate reduction therapy (gSRT) for MPS IIIC, with the goal of decreasing the expression of a gene, XYLT1, involved in the synthesis of the accumulated substrate, heparan sulfate (HS).
- Gene editing as a tool for developing cell based models of a lysosomal storage disorder: preliminary resultsPublication . Duarte, Ana Joana; Moreira, Luciana; Gaspar, Paulo; Alves, Sandra; Bragança, José; Amaral, OlgaIn this work, we aimed to establish a Fabry Disease (FD, OMIM: #301500) disease model using the CRISPR/Cas 9 system by knocking out a HDFa iPSC line. We also aimed to correct a nonsense mutation (p. W 287 X) in the iPSCs derived from a patient with FD. The cell lines used were generated in our laboratory, and the FD iPSC line is registered in the Human Pluripotent Stem Cell Registry with identification "INSAi 002-A". To fully evaluate the molecular and cellular physiological changes, further studies are still required. The development of innovative cell models, particularly for rare diseases like Lysosomal Storage Disorders, is beneficial for studying the pathophysiology of the disease.