Caracterização de regiões polimórficas em genes ligados à hipertensão - NOS3, G6PD e HBA numa população Moçambicana e numa população portuguesa

21ª Reunião da Sociedade Portuguesa de Genética Humana, 16-18 nov 2017Introdução: A hipertensão arterial é uma doença multifatorial, de elevada prevalência em Moçambique e Portugal (respectivamente 33,1%[1] e 42,2%[2]). Uma vez que a sintase do óxido nítrico endotelial (NOS3), a glucose-6-fosfato-desidrogenase (G6PD) e a alfa-globina (HBA) têm sido propostas como potenciais moduladoras da hipertensão arterial, pretendem-se neste estudo caraterizar as variantes genéticas mais comuns em duas populações, uma Moçambicana e outra Portuguesa. Material e Métodos: Foram analisadas 22 amostras de DNA provenientes do Hospital Central de Maputo e 87 provenientes do Hospital de Santa Maria. Para a pesquisa do número de repetições em tandem (VNTR) no intrão 4 do gene NOS3 foi usada a PCR, para a pesquisa do SNP rs1050829 no gene G6PD foi usado a PCR-RFLP e para a pesquisa da deleção alfa-talassémica de -3,7kb no agrupamento génico da alfa-globina foi usada uma metodologia de Gap-PCR. As frequências alélicas e genotípicas foram calculadas e analisadas com recurso ao programa estatístico SPSS 22.0 Resultados: Os resultados mostram que em relação ao gene HBA, a população Moçambicana analisada apresenta a frequência de 59% para o alelo mutado e de 41% para o alelo normal, em contraste com o observado para a população Portuguesa onde foi detetada a frequência de 1% para o alelo mutado e 99% para o alelo normal. No gene G6PD, observou-se na população Moçambicana a frequência de 76% para o alelo mutado e 24% para o alelo normal e para a população Portuguesa analisada observou-se que o alelo mutado apresenta a frequência de 1% e o alelo normal a frequência de 99%. Para o VNTR em NOS3, na população Moçambicana os alelos 4a e 4b apresentam respetivamente a frequência de 32% e 68%, enquanto na população Portuguesa os mesmos alelos apresentam respetivamente a frequência de 12% e 88%. Discussão: Estes resultados preliminares mostram a caracterização da frequência de regiões polimórficas em três genes potencialmente influentes no desenvolvimento da hipertensão em duas populações distintas. Encontra-se em estudo um outro conjunto de indivíduos controlos, não hipertensos, que permitirão através de estudos de associação avaliar a contribuição dos referidos polimorfismos para esta patologia. [1] Damasceno A et al. Hypertension 2009; 54:77. [2] Polonia J et al. Journal of Hypertension 2014; 32:1211.info:eu-repo/semantics/publishedVersio

Projeto Crês@Arte : práticas estéticas e pedagógicas em discussão

Trabalho de conclusão de curso (graduação)—Universidade de Brasília, Instituto de Artes, Departamento de Artes Cênicas, Programa Pró-licenciatura, Licenciatura em Teatro a Distância, 2014.Esta pesquisa visa analisar as práticas estéticas e pedagógicas do projeto Cres@arte da Secretaria de Educação de Itabira, criado em 2002, cujo objetivo é a inclusão social, tendo como fio condutor ações educativas aliadas ao fazer teatral, num contexto de educação não-formal, que atende prioritariamente crianças e adolescentes em situação de risco e exclusão social. Para o desenvolvimento da pesquisa, a metodologia utilizada foi a análise documental dos relatórios anuais produzidos pelo projeto no período de 2002 à 2014

Genetic modifiers of the intermediate phenotypes in sickle cell anemia

21ª Reunião da Sociedade Portuguesa de Genética Humana, 16-18 nov 2017Sickle cell anemia (SCA) is an inherited blood disorder characterized by the presence of hemoglobin S (HbS). This disease is caused by a single point mutation in the beta-globin gene with a corresponding amino acid substitution at the sixth position of the beta-globin chain. Vaso-occlusion and hemolytic anemia are the major features of this disease, however, SCA patients present clinical and hematologic variability that cannot be only explained by the single mutation. Others genetic modifiers and environmental factors are important for the clinical phenotype. We studied the association between several hematological and biochemical parameters and a set of genetic variants in 26 pediatric SCA patients. Myeloperoxidase (MPO) and placental growth factor (PlGF) were determined by ELISA (R&D Systems Inc.). Amplification of DNA samples for the rs1050829 characterization, in the glucose-6-phosphate dehydrogenase (G6PD) gene, was performed by PCR followed by restriction fragment length analysis. A multiplex PCR assay was used for simultaneous amplification of glutathione S-transferases mu (GSTM1) and theta (GSTT1). All statistical tests were performed with SPSS 24.0 software. Our results show higher levels of MPO (p<0.001) and PlGF (p=0.048) in SCA patients, compared with healthy adult controls. Moreover, in these patients we found associations between: 1) lower levels of total hemoglobin and the GSTM1 null genotype (p=0.044); 2) higher levels of HbS with the rs1050829_G genotype (hemizygous males) in the G6PD gene (p=0.026). We suggest that the mentioned polymorphisms in GSTM1 and G6PD genes may act as genetic modifiers in SCA, which could be useful for the prediction of increased susceptibility to complications. Furthermore, our results reinforce the importance to study biochemical parameters for a better understanding of the clinical outcome of this disease.info:eu-repo/semantics/publishedVersio

Bases de Tröger fluorescentes por ESIPT para a utilização em sondas intercalantes de DNA

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Genetic variants in endothelial nitric oxide synthase gene are modifiers of the hemolysis phenotype in Sickle Cell Anemia

Sickle Cell Anemia (SCA) is an autosomal recessive hereditary anemia characterized by the presence of hemoglobin S (Hb S). This disease is caused by a single mutation in beta-globin gene with a corresponding amino acid substitution at the sixth position of the beta-globin chain. The easily ability of Hb S to polymerize in deoxygenated conditions gives rise to abnormal sickled red blood cells. Vaso-occlusion and hemolytic anemia are the major features of this disease, however SCA patients present clinical and hematologic variability that cannot be only explained by the single mutation in the beta-globin gene. Others genetic modifiers and environmental effects are important in the clinical phenotype. We have studied the association between hematological and biochemical parameters (Hb S, total Hb, red cell distribution width (RDW), neutrophils, transmembrane reductase, methemoglobin reductase, serum lactate dehydrogenase (LDH), total bilirubin and reticulocyte count) and some genetic variants, from several candidate genes, in 26 paediatric SCA patients. Our results show a significant statistical association between two endothelial nitric oxide synthase (eNOS) single nucleotide polymorphisms (SNPs) and two haemolysis parameters. Both the rs2070744_TT and the rs1799983_GG genotypes are associated with an increased reticulocyte count (p =0.02 and 0.01, respectively) and higher serum LDH level (p = 0.04 and 0.04, respectively). Our findings suggest that polymorphisms in the eNOS gene may act as genetic modifiers of the haemolysis process that could provide utility for the prediction of increased susceptibility to haemolysis-related complications. Furthermore, our results reinforce the importance of nitric oxide (NO) bioactivity in SCA. We presume that NO, and possible its precursors such as L-arginine or L-citrulline, might be used as pharmacological tools to improve the quality of life of these patients

Assessment of the biotic effects of cephalexin on clinical strains of staphylococcus aureus and enterococcus faecalis isolated from a polymicrobial infection

info:eu-repo/semantics/publishedVersio

Clinical impact of HFE Mutations in portuguese patients with Chronic Hepatitis C

INTRODUCTION: Chronic hepatitis C (CHC) is often associated with alterations in iron and lipid metabolisms, which may affect the long-term prognosis and the response to antiviral treatment. Some studies suggested that the occurrence of HFE mutations may contribute to modulate these metabolisms in CHC. Here, the prevalence of two HFE mutations (C282Y and H63D) was determined in a group of Portuguese CHC patients and the findings were correlated with clinical, histological and virulogical features. MATERIALS AND METHODS: 183 CHC patients (118 males and 65 females), mean age 45.84±11.46 years and IMC 25.45±3.96 Kg/m2. Eighty two (44.8%) were treated with standard antiviral therapy and divided into 3 groups: non response (NR)-25.6%, relapse (RR)-9.8% and sustained response (SR)-64.6%. HCV-RNA and genotype were determined by PCR. Liver steatosis, fibrosis stage and degree of necroinflammation (grading) were assessed by liver biopsy (Peter Scheuer score) and clinical parameters were measured by standard techniques: AST, ALT, GGT, lipid profile (LDL, HDL, total cholesterol and triglycerides), iron metabolism (iron, ferritin, transferrin and transferrin saturation), haptoglobin, ceruloplasmin, insulin, glucose, peptide-C and HOMA. Antioxidant potential (tGSH/GSSG ratio) was evaluated by spectrofluorimetry. HFE_H63D and C282Y polymorphisms were analyzed by PCR-RFLP and statistical analysis was performed with SPSS 16.0 (level of significance of p<0.05). Patients’ exclusion criteria: other chronic liver diseases, alcohol ingestion >40g/day, HIV infection, metabolic and autoimmune diseases. RESULTS: Sixty two patients (33.9%) carried one or two mutant H63D allele (HD+DD), being 4.4% homozygous (DD). C282Y polymorphism was present in 5.5% of the patients; all were heterozygous. No difference was found comparing HFE_H63D and _C282Y polymorphisms with the type of antiviral response. Regarding H63D, we observe a decrease in the degree of necroinflammation (grading) and in tGSH/GSSG ratio and an increase in total cholesterol for carriers of the mutant allele (HD+DD) comparing to HH individuals (p=0.004; p=0.006; p=0.042, respectively). For C282Y, our study revealed that heterozygous CY had higher serum iron and transferrin saturation levels (p=0.038; p=0.006, respectively) and lower total cholesterol (p<0.0001). In the total studied population, this last clinical parameter was found to be increased in patients with less necroinflammation and steatosis (p=0.023; p=0.046) and patients with higher fibrosis stages (moderate and intense) showed higher serum iron levels. CONCLUSIONS: These data suggest a relevant role of HFE_H63D and C282Y polymorphisms in some clinical and histological features of chronic hepatitis C.Partially funded by FCT: PTDC/SAU-GMG/103307/200

Interaction of PABPC1 with the translation initiation complex is critical to the NMD resistance of AUG-proximal nonsense mutations

Nonsense-mediated mRNA decay (NMD) is a surveillance pathway that recognizes and rapidly degrades mRNAs containing premature termination codons (PTC). The strength of the NMD response appears to reflect multiple determinants on a target mRNA. We have previously reported that mRNAs containing PTCs in close proximity to the translation initiation codon (AUG-proximal PTCs) can substantially evade NMD. Here, we explore the mechanistic basis for this NMD resistance. We demonstrate that translation termination at an AUG-proximal PTC lacks the ribosome stalling that is evident in an NMD-sensitive PTC. This difference is associated with demonstrated interactions of the cytoplasmic poly(A)-binding protein 1, PABPC1, with the cap-binding complex subunit, eIF4G and the 40S recruitment factor eIF3 as well as the ribosome release factor, eRF3. These interactions, in combination, underlie critical 3′–5′ linkage of translation initiation with efficient termination at the AUG-proximal PTC and contribute to an NMD-resistant PTC definition at an early phase of translation elongation

Ploidy mosaicism and allele-specific gene expression differences in the allopolyploid Squalius alburnoides

<p>Abstract</p> <p>Background</p> <p><it>Squalius alburnoides </it>is an Iberian cyprinid fish resulting from an interspecific hybridisation between <it>Squalius pyrenaicus </it>females (P genome) and males of an unknown <it>Anaecypris hispanica-</it>like species (A genome). <it>S. alburnoides </it>is an allopolyploid hybridogenetic complex, which makes it a likely candidate for ploidy mosaicism occurrence, and is also an interesting model to address questions about gene expression regulation and genomic interactions. Indeed, it was previously suggested that in <it>S. alburnoides </it>triploids (PAA composition) silencing of one of the three alleles (mainly of the P allele) occurs. However, not a whole haplome is inactivated but a more or less random inactivation of alleles varying between individuals and even between organs of the same fish was seen.</p> <p>In this work we intended to correlate expression differences between individuals and/or between organs to the occurrence of mosaicism, evaluating if mosaics could explain previous observations and its impact on the assessment of gene expression patterns.</p> <p>Results</p> <p>To achieve our goal, we developed flow cytometry and cell sorting protocols for this system generating more homogenous cellular and transcriptional samples. With this set-up we detected 10% ploidy mosaicism within the <it>S. alburnoides </it>complex, and determined the allelic expression profiles of ubiquitously expressed genes (<it>rpl8</it>; <it>gapdh </it>and <it>β-actin</it>) in cells from liver and kidney of mosaic and non-mosaic individuals coming from different rivers over a wide geographic range.</p> <p>Conclusions</p> <p>Ploidy mosaicism occurs sporadically within the <it>S. alburnoides </it>complex, but in a frequency significantly higher than reported for other organisms. Moreover, we could exclude the influence of this phenomenon on the detection of variable allelic expression profiles of ubiquitously expressed genes (<it>rpl8</it>; <it>gapdh </it>and <it>β-actin</it>) in cells from liver and kidney of triploid individuals. Finally, we determined that the expression patterns previously detected only in a narrow geographic range is not a local restricted phenomenon but is pervasive in rivers where <it>S. pyrenaicus </it>is sympatric with <it>S. alburnoides</it>.</p> <p>We discuss mechanisms that could lead to the formation of mosaic <it>S. alburnoides </it>and hypothesise about a relaxation of the mechanisms that impose a tight control over mitosis and ploidy control in mixoploids.</p