Browsing by Author "Duarte, Ana"
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- Characterization of a comon IDUA in the Portuguese populationPublication . Ribeiro, Diogo; Duarte, Ana; Amaral, OlgaMucopolysaccharidosis type I (MPS I; OMIM #252800) is an autosomal recessive disorder, which results from the defective activity of the lysosomal enzyme α-L-iduronidase (IDUA, EC 3.2.1.76). In MPS I, this enzyme deficiency results in a progressive accumulation of the undegraded substrates within tissue lysosomes and fluids, leading to the clinical manifestations of the disease. W402X has been described as common in patients of European Caucasian origin. Moreover, this mutation has been considered to play an important role in terms of the pathophysiology of MPS I. The results of current functional experiments will be presented.
- CHIT1 genetic defects in the Portuguese populationPublication . Duarte, Ana; Ribeiro, Diogo; Amaral, OlgaChitotriosidase is an enzyme secreted by activated macrophages and a useful biomarker in several lysosomal and nonlysosomal diseases. However, chitotriosidase gene (CHIT1) mutations may lead to inaccuracy in the significance of this biomarker. Reports on the molecular spectrum of genetic variation in chitotriosidase are rare, and this is one of the few that focus on a specific population group. In this work we assessed the variation of CHIT1 mutations in ten normal controls and detected six missense alterations. G102S, a polymorphism with known altered catalytic properties, was the most frequent being detected in 4/10 individuals. Using allelic discrimination we tested 503 individuals, randomly sampled from the Portuguese population. Variant G102S was detected in 49.5% of the individuals and presented an allele frequency of 0.29. The results of this study showed that variability in CHIT1 gene is considerable and that G102S polymorphism presents a high frequency in the Portuguese.
- COVID-19-Associated Invasive Pulmonary Aspergillosis in the Intensive Care Unit: A Case Series in a Portuguese HospitalPublication . Ranhel, David; Ribeiro, Ana; Batista, Judite; Pessanha, Maria; Cristovam, Elisabete; Duarte, Ana; Dias, Ana; Coelho, Luís; Monteiro, Filipa; Freire, Pedro; Veríssimo, Cristina; Sabino, Raquel; Toscano, CristinaInvasive pulmonary aspergillosis (IPA) has become a recognizable complication in coronavirus disease 2019 (COVID-19) patients admitted to intensive care units (ICUs). Alveolar damage in the context of acute respiratory distress syndrome (ARDS) appears to be the culprit in facilitating fungal invasion in COVID-19 patients, leading to a COVID-19-associated pulmonary aspergillosis (CAPA) phenomenon. From November 2020 to 15 February 2021, 248 COVID-19 patients were admitted to our ICUs, of whom ten patients (4% incidence) were classified as either probable (six) or possible (four) CAPA cases. Seven patients had positive cultural results: Aspergillus fumigatus sensu stricto (five), A. terreus sensu stricto (one), and A. welwitschiae (one). Five patients had positive bronchoalveolar lavage (BAL) and galactomannan (GM), and two patients had both positive cultural and GM criteria. All but two patients received voriconazole. Mortality rate was 30%. Strict interpretation of classic IPA definition would have resulted in eight overlooked CAPA cases. Broader diagnostic criteria are essential in this context, even though differentiation between Aspergillus colonization and invasive disease might be more challenging. Herein, we aim to raise awareness of CAPA in view of its potential detrimental outcome, emphasizing the relevance of a low threshold for screening and early antifungal treatment in ARDS patients.
- CRISPR/Cas in iPSCs from Sphingolipidoses patientsPublication . Amaral, Olga; Duarte, Ana; Ribeiro, Diogo; Moreira, LucianaClustered Regularly Interspaced Short Palindromic Repeats (CRISPR) were found as an immune adaptive mechanism in bacteria and quickly were applied to various fields as a promising tool for gene editing. Lysosomal storage diseases (LSDs) are a group of metabolic disorders caused by defects in lysosomal proteins leading to accumulation of undigested macromolecules within the cells. The lack of good in vitro models hinders research of the pathophysiologic mechanisms and the development of new therapies. Induced pluripotent stem cells (iPSCs) are patient-specific and can be differentiated in any cell type. The advantage of iPSCs is to enable targeted studies in cells with the patient’s own background leading to more straightforward results than other models. Combining CRISPR and iPSCs is, therefore, a promising strategy. We aim to use CRISPR/Cas-mediated gene editing to provide more specific cellular models of disease, to correct causal mutations in LSDs and to create mutants for functional studies. In this work, we generated and characterized iPSCs from human fibroblasts obtained from Gaucher and Fabry patients (through Gaslini Institute) and will edit them with a CRISP/Cas9 approach. Because both gene editing and iPSCs generation require manipulating the cell’s genome, we envisage multiple check points along the workflow. It will be useful to compare the “native” mutated cells with the corrected cells that modulate the “disease in a dish”. Gene editing is still recent and the methods require improvement, namely increasing transfection rates and mutagenesis efficiency with less off-targets. Nevertheless, CRISPR/Cas is a promising alternative to other therapies, and every result contributes to the enhancement of this technology, broadening the validation of CRISPR application and making it an accessible option.
- Diagnóstico pré-natal: presente e futuroPublication . Amaral, Olga; Rocha, Hugo; Marques, Bárbara; Ferreira, Cristina; Duarte, AnaA identificação de alterações genéticas causadoras de malformação fetal ou de doença hereditária grave reveste-se de especial importância, permitindo delinear estratégias adequadas de aconselhamento genético, terapia e acompanhamento, de forma a disponibilizá-las atempadamente aos indivíduos afectados. Nesta actividade, os colaboradores do Departamento de Genética Humana do INSA irão mostrar as metodologias aplicadas neste âmbito, a forma como contribuem para o diagnóstico mais precoce e o contributo para obtenção de ganhos em saúde pública. Os visitantes terão oportunidade de ficar com uma visão do presente e do futuro na área de Diagnóstico Pré-Natal.
- A first step to open the neuronal box of Gaucher CellsPublication . Ribeiro, Diogo; Duarte, Ana; Santos, Renato; Amaral, OlgaThis work focuses on the differentiation and gene expression characterization of neural progenitor cells obtained from human induced pluripotent cells (hiPSCs) reprogrammed from type 3 GD (GD3) fibroblasts. GD3 patient fibroblasts (from an international cell bank) were cultured and reprogramed as previously described (https://doi.org/10.1016/j.scr.2019.101595). The resulting hiPSCs were differentiated into pre-neuronal cells and, at this stage, they were examined. The gene expression behavior of all neurogenesis genes (NES, MAP2 and OTX2) was similar but higher expression was observed in GD3 hiPSCs than in GD3 neural progenitor cells. With this work, we can conclude that, when working with hiPSCs in the process of creating disease-specific cell models it is most important to carry out a general gene expression characterization of the different cell lines involved in all stages.
- Gaucher Disease and iPSCs: what does the future hold?Publication . Amaral, Olga; Duarte, Ana; Ribeiro, Diogo; Santos, Renato; Bragança, JoséIntroduction: Currently we are working with induced pluripotent stem cells (iPSCs) in order to generate cells with the same genetic background as the donor patients and further differentiate them in cell types of interest for the study of specific diseases. We are manipulating human skin fibroblasts and have included multiple checkpoints along the procedures to avoid potential pitfalls.
- Genetic variation in CHIT 1Publication . Duarte, Ana; Ribeiro, Diogo; Amaral, OlgaChitotriosidase (EC.3.2.1.14) is an enzyme secreted by activated macrophages. This chitinase is useful as a biochemical marker in several lysosomal and nonlysosomal diseases due to its increased activity in such conditions (MIM#600031. CHIT1 variants may account for additional biochemical variability and should be considered when using chitotriosidase activity as a secondary evaluation marker in diagnosis and disease prognosis.
- Genética e cérebro na "fábrica de perguntas"Publication . Amaral, Olga; Alves, Sandra; Duarte, Ana; Ribeiro, Diogo; Rocha, Hugo; Coutinho, Francisca; Alves, Mariana; Moreira, Luciana; Matos, LilianaCom esta atividade desenvolvida no âmbito da semana aberta do INSA pretendeu-se demonstrar como a Genética e o cérebro são os centros de controlo do quotidiano. Na parte prática desenvolveram-se atividades "mãos na massa" e "minds on" relacionadas com os temas.
- Induced pluripotent stem cell line (INSAi002-A) from a Fabry Disease patient hemizygote for the rare p.W287X mutationPublication . Duarte, Ana; Ribeiro, Diogo; Santos, Renato; Moreira, Luciana; Bragança, José; Amaral, OlgaFabry Disease (FD) is a multisystemic X-linked disorder that belongs to the group of lysosomal storage disorders (LSDs). Causal mutations on alpha-galactosidase A (α-Gal A) commonly lead to abnormal protein and consequently to FD. Since it is an X-linked disease, males are primarily affected. This work describes the generation of induced Pluripotent Stem Cells (iPSCs) from skin fibroblasts from a FD patient, using non-integrative episomal vectors. Differentiation of iPSCs can be applied to generate a variety of cell types with high degree of genetic complexity that would otherwise be difficult to obtain.