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- Generation of a human induced pluripotent stem cell line (UALGi001-A) from a patient with Left-Ventricular Noncompaction CardiomyopathyPublication . Calado, Sofia; Bento, Dina; Justino, David; Mendes-Silva, Leonardo; Marques, Nuno; Bragança, JoséLeft Ventricular Noncompaction Cardiomyopathy (LVNC) is characterized by excessive trabeculation of the left ventricle. To date, mutations in more than 40 genes have been associated with LVNC, however the exact mechanisms underlying the disease remain unknown. Here, we describe an induced pluripotent stem cell (iPSC) line (UALGi001-A) from a LVNC patient (LVNC-iPSC) that does not present mutations in the genes most commonly associated with the disease (van Waning et al., 2019). The LVNC-iPSC exhibited full pluripotency and differentiation potential, and retained a normal karyotype after reprogramming. This in vitro cellular model will be useful to study the molecular, genetic and functional aspects of LVNC.
- Functional analysis of two novel TBX5 variants present in individuals with Holt-Oram syndrome with different clinical manifestationsPublication . Varela, Debora; Varela, Tatiana; Conceição, Natércia; Ferreira, Angela; Marques, Nuno; Silva, Ana Paula; Azevedo, Pedro; Pereira, Salome; Camacho, Ana; de Jesus, Ilidio; Cancela, M. LeonorHolt-Oram syndrome (HOS) is a rare disorder characterized by cardiac and upper-limb defects. Pathogenic variants in TBX5-a gene encoding a transcription factor important for heart and skeletal development-are the only known cause of HOS. Here, we present the identification and functional analysis of two novel TBX5 pathogenic variants found in two individuals with HOS presenting distinct phenotypes. The individual with the c.905delA variant has a severe cardiac phenotype but mild skeletal defects, unlike the individual with the c.246_249delGATG variant who has no cardiac problems but severe upper limbs malformations, including phocomelia. Both frameshift variants, c.246_249delGATG and c.905delA, generate mRNAs harbouring premature stop codons which, if not degraded by nonsense mediated decay, will lead to the production of shorter TBX5 proteins, p.Gln302Argfs*92 and p.Met83Phefs*6, respectively. Immunocytochemistry results suggest that both mutated proteins are produced and furthermore, like the wild-type protein, p.Gln302Argfs*92 mutant appears to be mainly localized in the nucleus, in contrast with p.Met83Phefs*6 mutant that displays a higher level of cytoplasmic localization. In addition, luciferase activity analysis revealed that none of the TBX5 mutants are capable of transactivating the NPPA promoter. In conclusion, our results provide evidence that both pathogenic variants cause a severe TBX5 loss-of-function, dramatically reducing its biological activity. The absence of cardiac problems in the individual with the p.Met83Phefs*6 variant supports the existence of other mechanisms/genes underlying the pathogenesis of HOS and/or the existence of an age-related delay in the development of a more serious cardiac phenotype. Further studies are required to understand the differential effects observed in the phenotypes of both individuals.
- Congenital left ventricular apical aneurysm presenting as ventricular tachycardiaPublication . Amado, José; Marques, Nuno; Candeias, Rui; Gago, Paula; de Jesus, IlidioThe authors present the case of a 34-year-old male patient seen in our department due to palpitations. On the electrocardiogram monomorphic ventricular tachycardia (VT) was documented, treated successfully with amiodarone. The subsequent study revealed a normal echocardiogram and an apical aneurysm of the left ventricle on magnetic resonance imaging, confirmed by computed tomography coronary angiography that also excluded coronary disease.He underwent an electrophysiological study to determine the origin of the VT and to perform catheter ablation using electroanatomical mapping. VT was induced and radiofrequency applications were performed in the left ventricular aneurysm area. VT was no longer inducible, with acute success. Despite this it was decided to implant a subcutaneous implantable cardioverter-defibrillator (ICD). Eight months after the ablation the patient was admitted again due to VT, treated by the ICD. (C) 2016 Sociedade Portuguese de Cardiologia. Published by Elsevier Espana, S.L.U. All rights reserved.
- Generation and cardiac differentiation of a human induced pluripotent stem cell line UALGi002-A from a female patient with Left-Ventricular Noncompaction CardiomyopathyPublication . Calado, Sofia; Bento, Dina; Marques, Nuno; Bragança, JoséLeft Ventricular Noncompaction Cardiomyopathy (LVNC) is characterized by abnormal number and prominence of trabeculations of the left ventricle of the heart. Although LVNC has been associated with mutations in several genes encoding for transcriptional regulators, ion channels, sarcomeric and mitochondrial proteins, approximately 60% of LVNC patients do not present these genetic alterations. Here, we describe an induced pluripotent stem cell (hiPSC) line (UALGi002-A) originated from a LVNC female patient (LVNC-hiPSC) who does not present any previously known mutations associated to LVNC. The LVNC-hiPSC exhibited full pluripotency and differentiation potential and retained a normal karyotype after reprogramming. Moreover, the LVNC-hiPSC differentiated into contracting cardiomyocytes. This cellular model will be useful to study the molecular, genetic and functional aspects of LVNC in vitro.
- Screening for Fabry disease in patients with left ventricular noncompactionPublication . Azevedo, Olga; Marques, Nuno; Craveiro, Nuno; Pereira, Ana Rita; Antunes, Hugo; Reis, Liliana; Guerreiro, Rui Azevedo; Pontes dos Santos, Rui; Miltenberger-Miltenyi, Gabriel; Sousa, Nuno; Cunha, DamiãoIt is unclear whether left ventricular noncompaction (LVNC) is a distinct cardiomyopathy or a morphologic manifestation of different cardiomyopathies. We previously reported a case of LVNC in a Fabry disease (FD) patient, but it remains to be clarified whether LVNC is a cardiac manifestation of FD, a coincidental finding or an overdiagnosis, which has major therapeutic implications. This study aims to determine the prevalence of FD among patients with LVNC.
- Left ventricular non-compaction: challenges in the etiopathogenesis and risk stratification of sudden cardiac death in clinical practicePublication . Marques, NunoIn their study published in this issue of the Journal,1 Oliveira et al. elegantly described a family of patients with left ventricular non-compaction (LVNC), illustrating the challenges in clinical practice regarding etiological investigation and risk stratification of sudden cardiac death in these patients. A family history of LVNC has been described in about 30% of cases2 and a pathogenic mutation has been found in nearly one-third.3 Although LVNC is a genetically heterogeneous cardiomyopathy, sarcomere mutations represent more than half of the known genetic causes, especially in adults, and MYH7 is one of the most commonly mutated genes.2 Nevertheless, the causal relation between genetic variants and the LVNC phenotype remains to be ascertained in the majority of cases. This case report underlines the importance of a specialized cardiomyopathy team in the systematic genetic and clinical screening of family relatives and the interpretation of the clinical significance of genetic variants in LVNC.
- Predictors of Fabry disease in patients with hypertrophic cardiomyopathy: how to guide the diagnostic strategy?Publication . Azevedo, Olga; Marques, Nuno; Reis, Liliana; Cruz, Inês; Craveiro, Nuno; Antunes, Hugo; Lourenço, Carolina; Gomes, Renata; Guerreiro, Rui Azevedo; Faria, Ricardo; Sá, Fernando; Lima, Rui; Gaspar, Paulo; Faria, Rui; Miltenberger-Miltenyi, Gabriel; Sousa, Nuno; Cunha, DamiãoFabry disease (FD) is a treatable cause of hypertrophic cardiomyopathy (HCM). We aimed to determine the independent predictors of FD and to define a clinically useful strategy to discriminate FD among HCM.
- p.G360R is a pathogenic GLA gene mutation responsible for a classic phenotype of Fabry diseasePublication . Carvalho Silva, Daniela; Marques, Nuno; Azevedo, Olga; Miltenberger-Miltenyi, Gabriel; Bento, Dina; Guedes, Joao; Azevedo, Pedro; Bispo, Joao; Mota, Teresa; Fernandes, Raquel; Nzwalo, Hipólito; Cabrita, Ana; Ramos, André; de Jesus, IlidioThe authors report the case of a classic phenotype of Fabry disease in a 60-year-old male patient presenting with left ventricular hypertrophy and stroke. Genetic analysis revealed 2 GLA-gene variants, i.e., p.R356Q and p.G360R. This clinical case highlights that the finding of 2 or more GLA gene variants in a Fabry patient should lead to a careful evaluation in order to determine their exact role in the condition. This case also provides the first clinical evidence that the p.G360R mutation is pathogenic and responsible for a classic phenotype of Fabry disease. The clinical improvement following the initiation of enzyme replacement therapy reinforces the importance of Fabry disease awareness and diagnosis in patients exhibiting red flags, such as left ventricular hypertrophy and stroke.
- Surviving cardiac arrest: what happens after admission to the intensive care unit?Publication . Menezes Fernandes, Raquel; Nuñez, Daniel; Marques, Nuno; Dias, Cláudia Camila; Granja, CristinaPatients successfully resuscitated from cardiac arrest (CA) are admitted to the intensive care unit (ICU) for post-resuscitation care. These patients' prognosis remains dismal, with only a minority surviving to hospital discharge. Understanding the clinical factors involved in the management of these patients is essential to improve their prognosis.
- Reprogramming iPSCs to study age-related diseases: models, therapeutics, and clinical trialsPublication . Esteves, Filipa; Brito, David; Rajado, Ana Teresa; Silva, Nádia; Apolónio, Joana; Roberto, Vania Palma; Araújo, Inês Maria; Nóbrega, Clévio; Castelo-Branco, Pedro; Bragança, José; P. Andrade, Raquel; M. Calado, Sofia; Faleiro, L; Matos, Carlos A; Marques, Nuno; Marreiros, Ana; Nzwalo, Hipólito; Pais, Sandra; Palmeirim, Isabel; S, Simão; Joaquim, Natércia; Miranda, Rui; Pêgas, António; Raposo, Daniela Marques; Sardo, AnaThe unprecedented rise in life expectancy observed in the last decades is leading to a global increase in the ageing population, and age-associated diseases became an increasing societal, economic, and medical burden. This has boosted major efforts in the scientific and medical research communities to develop and improve therapies to delay ageing and age-associated functional decline and diseases, and to expand health span. The establishment of induced pluripotent stem cells (iPSCs) by reprogramming human somatic cells has revolutionised the modelling and understanding of human diseases. iPSCs have a major advantage relative to other human pluripotent stem cells as their obtention does not require the destruction of embryos like embryonic stem cells do, and do not have a limited proliferation or differentiation potential as adult stem cells. Besides, iPSCs can be generated from somatic cells from healthy individuals or patients, which makes iPSC technology a promising approach to model and decipher the mechanisms underlying the ageing process and age-associated diseases, study drug effects, and develop new therapeutic approaches. This review discusses the advances made in the last decade using iPSC technology to study the most common age-associated diseases, including age-related macular degeneration (AMD), neurodegenerative and cardiovascular diseases, brain stroke, cancer, diabetes, and osteoarthritis.