DPSPDNT - Posters/abstracts em congressos nacionais
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- Alpha-thalassemia due to novel deletions and complex rearrangements in the subtelomeric region of chromosome 16pPublication . Ferrão, José; Silva, Marisa; Gonçalves, Lúcia; Gomes, Susana; Loureiro, Pedro; Coelho, Andreia; Miranda, Armandina; Seuanes, Filomena; Batalha Reis, Ana; Pina, Francisca; Maia, Raquel; Kjollerstrom, Paula; Monteiro, Estela; F. Lacerda, João; Lavinha, João; Gonçalves, João; Faustino, PaulaIntroduction: Inherited deletions removing the α-globin genes and/or their upstream regulatory elements (MCSs) give rise to alpha-thalassemia, one of the most common genetic recessive disorders worldwide. The pathology is characterized by microcytic hypochromic anemia due to reduction of the α-globin chain synthesis, which are essential for hemoglobin tetramerization. Material and Methods: In order to clarify the suggestive α-thalassemia phenotype in eleven patients, we performed Multiplex Ligation-dependent Probe Amplification with commercial and synthetic engineered probes, gap-PCR, and Sanger sequencing to search for deletions in the subtelomeric region of chromosome 16p. Results: We have identified five distinct large deletions, two of them novel, and one indel. The deletions range from approximately 3.3 to 323 kb, and i) remove the whole α-globin cluster; or ii) remove exclusively the upstream regulatory elements leaving the α-globin genes structurally intact. The indel consists in the loss of MCS-R2 (HS-40), which is the most important distal regulatory element for the α-globin gene expression, and the insertion of 39 bp, seemingly resulting from a complex rearrangement involving two DNA segments (probably from chromosome 3q) bridging the deletion breakpoints with a CC-bp orphan sequence in between. Finally, in one patient no α-globin deletion or point mutation were found. This patient revealed to be a very unusual case of acquired alpha-thalassemia associated with a myelodysplastic syndrome. Conclusions: Our study widens the spectrum of molecular lesions by which α-thalassemia may occur and emphasizes the importance of diagnosing large α-zero-deletions to provide patients with appropriate genetic counseling.
- An integrative system biology approach for dissecting Autism Spectrum DisorderPublication . Asif, M.; Rasga, C.; Martiniano, H.; Santos, J.X.; Marques, A.R.; Couto, F.M .; Vicente, A.M.Autism Spectrum Disorder (ASD) is characterized by a wide spectrum of behavioral presentation. Many genetic factors are implicated in ASD, however their role in the heterogeneous ASD phenotype remains elusive. Using data mining-based integrative approaches, we seek to identify patterns of association between ASD phenotypic subgroups and altered biological processes inferred from CNVs targeting brain genes.
- An integrative system biology approach to delineate complex genotype-phenotype associations in Autism Spectrum DisorderPublication . Asif, M; Martiniano, Hugo F.; Rasga, Celia; Marques, Ana R.; Santos, Joao X.; O., Guiomar; Couto, Francisco M.; Vicente, Astrid M.Introduction: Autism Spectrum Disorder (ASD) is characterized by deficits in social interaction and communication, and by the presence of repetitive behavior and/or restricted interests. ASD manifests with heterogeneous phenotype and has an estimated global prevalence of ~1%;- ASD is difficult to diagnose in very young children. Delayed diagnosis leads to delay in applying behavioral therapies that may help to reduce symptoms, particularly when applied at young age; - Copy Number Variant (CNV) screening has been widely used for primary diagnosis purposes and is associated with phenotypic variability in ASD patients; - Large scale studies have identified hundreds of ASD implicated loci; however, mechanistic and clinical interpretation of these disease-causing variants remains elusive.
- Analysis of Genetic Markers for Cardiovascular Disorders in a Portuguese population with Familial HypercholesterolaemiaPublication . Gomes, A.; Santos, T.; Costa, L.; Bourbon, M.Familial Hypercholesterolaemia is a genetic disorder characterized by an increase in TC and LDLC leading to premature atherosclerosis (ATH) and cardiovascular disorders (CVD) but not all FH patients develops premature CVD. Early identification of FH patients at an even increased risk of developing CVD is important. Genetic markers could improve risk stratification for this patients. Inflammation has been considered to be involved in the pathogenesis of CVD and genetic and oxidative stress markers may also contribute to ATH and CVD outcome.
- Analysis of Genetic Markers for Cardiovascular Disorders in a Portuguese population with Familial HypercholesterolaemiaPublication . Gomes, A.; Santos, T.; Bourbon, M.Familial Hypercholesterolaemia (FH) is a genetic disorder leading to an increase in levels of total and low density lipoprotein cholesterol promoting atherosclerosis (ATH) and premature cardiovascular disease (CVD). Inflammation has been considered to be involved in the pathogenesis of CVD, namely the activity of pro-inflammatory cytokines and acute phase proteins. Genetic and oxidative stress markers may contribute to ATH and CVD outcome. We intended to investigate the role of genetic, inflammatory and oxidative biomarkers in the clinical outcome of FH patients and study its putative correlation with CVD. We selected 41 FH patients with CVD, 91 without CVD and 49 healthy individuals. All individuals were characterized through the determination of the lipid profile (high density lipoprotein, LDL and total cholesterol (TC), triglycerides (TG), apolipoproteinA, apolipoproteinB, lipoprotein(a)), measurement of serum concentration of inflammatory markers (ceruloplasmin, haptoglobin and C reactive protein), pro-inflammatory cytokines (interleukin-6 (IL6) and tumor necrosis factor-alpha (TNFα)), homocysteine and markers of antioxidant / pro-oxidant status (nitric oxid (NO) and oxidized LDL). Genetic characterization was achieved by the study of polymorphisms in the genes encoding for LPL, APOAV, APOCIII, TNF-α, IL6, MTHFR and NOS. The results showed that the group of FH patients with CVD presented increased TC (p<0,001) and LDL cholesterol (p=0,001) and apoB (p<0,001) levels and decreased apoA1 (p=0,021) levels in relation to the FH group without CVD. In the FH group with CVD it was observed the highest oxLDL and the lowest NO concentrations. APOAV-1131C and APOCIII 3238G allele were associated with higher TG levels (p=0,013; p=0,042) in the FH group without CVD. MTHFR 677T allele was associated with high TC levels (p=0,006) in the FH group with CVD. Markers of lipid metabolism are evident between the groups analyzed however inflammatory and genetic markers need further studies to improve our knowledge of their role in CVD outcome.
- Ancestry of the major long-range regulatory site of the α-globin genes in the Portuguese population with the common 3.7kb α-thalassemia deletionPublication . Pena, Rita; Lopes, Pedro; Gaspar, Gisela; Miranda, Armandina; Faustino, PaulaThe α-major regulatory element (known as HS-40) has a crucial role in the long-range regulation of the α-globin gene expression. This element is genetically polymorphic and six haplotypes (A to F) have been identified in different populations, with haplotype D almost exclusively found in African populations. This study aimed to identify the HS-40 haplotype associated with the common 3.7kb α-thalassemia deletion (-α3.7del) in the Portuguese population, and investigate its ancestry. We searched for the -α3.7del in 111 selected Portuguese individuals by Gap-PCR. In addition, a DNA fragment containing the HS-40 was amplified by PCR and Sanger sequenced. Statistical analysis was performed using R software. Fifty individuals have the wild-type α-globin genotype (group I), 34 are heterozygous for the -α3.7del (group II) and 27 are homozygous (group III). Regarding the HS-40, four haplotypes were found (A to D). The distribution of HS-40 haplotypes and genotypes are significantly different between groups with and without the -α3.7del (p<0.001), being haplotype D and genotype AD the most prevalent in group III. Furthermore, multiple correspondence analysis revealed that individuals without the -α3.7del are grouped with other European populations, while samples with the -α3.7del are split from these and found more related to the African population. This study revealed for the first time an association of a specific HS-40 haplotype with the -α3.7del in the Portuguese population, and its likely African ancestry. These results may have a clinical importance as in vitro analysis of haplotype D showed a descrease in its enhancer activity on α-globin genes.
- Are Diet-related Factors Associated with Differences in Mean Arterial Pressure Among Portuguese Natives and African Migrants? A Study with Medicated Hypertensive Patients followed at Lisbon Primary Health Care CentresPublication . Cardoso, I.; Alarcão, V.; Simões, R.; Guerra, F.; Pinto, A.; Nicola, P.; Fernandes, M.; Guiomar, S.; Rocha, E.
- Auditoria Remota para Avaliação do Controlo da Qualidade em Quatro Laboratórios Clínicos, Portugal e Brasil, com foco nos parâmetros hematológicos (hemoglobina, eritrócitos, leucócitos e plaquetas) - 2018Publication . Carletto, Aline; Miranda, Armandina; Faria, Ana Paula; Marques, CristinaA auditoria externa é uma das metodologias de avaliação do Sistema de Gestão da Qualidade (SGQ) aplicada a laboratórios clínicos, que visa verificar o cumprimento dos requisitos normativos e a conformidade com as boas práticas laboratoriais. O Controlo da Qualidade Analítico (CQA) no contexto do laboratório clínico é um sistema de deteção e controlo de erros dos métodos analíticos que inclui o Controlo da Qualidade Interno (CQI) e o Controlo de Qualidade Externo (CQE), permitindo a emissão de resultados precisos e exatos. O hemograma é um dos testes laboratoriais mais frequentemente solicitados, constituindo a base de numerosas intervenções médicas, sendo, portanto, de primordial importância, a transmissão de resultados analíticos confiáveis. O objetivo deste trabalho é avaliar o SGQ de quatro laboratórios clínicos, com foco nos resultados do CQI e do CQE na área de hematologia, como indicadores da qualidade. A avaliação simula uma auditoria de qualidade remota tendo como referencial normativo NP EN ISO 15189: 2014.
- Autism Spectrum Disorder (ASD): genetic, epigenetic and environmental issuesPublication . Marques, Ana Rita; Martiniano, Hugo; Xavier-Santos, João; Asif, M.; Oliveira, Guiomar; Romão, Luísa; Vicente, Astrid M.Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication/interaction and by unusual repetitive and restricted behaviors and interests. ASD often co-occurs in the same families with other neuropsychiatric diseases (NPD), such as intellectual disability, schizophrenia, depression and attention deficit hyperactivity disorder. Genetic factors have an important role in ASD etiology. Multiple copy number variants (CNVs) and single nucleotide variants (SNVs) in candidate genes have been associated with an increased risk to develop ASD [8-10]. Nevertheless, recent heritability estimates and the high genotypic and phenotypic heterogeneity characteristic of ASD indicate a role of environmental and epigenetic factors, such as long noncoding RNA (lncRNA) and microRNA (miRNA), as modulators of genetic expression and clinical presentation. The aim of this project is to understand the role of lncRNA, miRNA and other epigenetic factors in ASD. For this purpose we are, in a first approach, screening for CNVs and SNVs encompassing lncRNA and miRNA loci in two large datasets: the Autism Genome Project (AGP), with CNV data from 2611 autism trios and the ARRA Autism Sequencing Collaboration, with whole exome sequencing data (WES) from 3056 autism trios. These datasets include data from Portuguese ASD probands recruited by our team. Thus far we have explored the variant call format files that contain all WES variants called by GATK. We started by testing different annotation tools and databases to obtain the best subset of variants that will be filtered according to their genomic coordinates and their pathogenic status. We are also selecting the CNVs from the AGP file that contain lncRNA and miRNA loci. The goal is to identify individuals with potential mutations in lncRNA and miRNA loci that may be disrupting their function upon target genes. Experimental validation will be carried out by measuring gene expression in these patients. A second approach will involve exploring available multiplex families in which ASD co-occurs with other NPDs. Segregation analysis will allow us to define patterns of NPD transmission, identify common gene variants and explore the role of modulating epigenetic factors that lead to differential disease expression.
- Autism Spectrum Disorder (ASD): genetic, epigenetic and environmental issuesPublication . Marques, Ana Rita; Martiniano, Hugo; Xavier-Santos, João; Asif, M.; Oliveira, Guiomar; Luísa, Romão; M. Vicente, AstridAutism Spectrum Disorder (ASD) is a neurodevelopmental disorder which affects the brain structure and the proper establishment of the neuronal connectivity.