Browsing by Author "Ferreira, Joana"
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- Air pollution: a public health approach for PortugalPublication . Torres, Pedro; Ferreira, Joana; Monteiro, Alexandra; Costa, Solange; Pereira, Maria Carmo; Madureira, Joana; Mendes, Ana; Teixeira, João PauloAt the global level, several epidemiological studies have conclusively pointed out the associations between short-term exposure to air pollution and acute health effects, and long-term exposure with adverse health effects such as premature mortality from severe respiratory and cardiovascular diseases. This study intended to characterize exposures and their adverse health effects. Three independent sets of vectors were analyzed on a nationwide level and annual basis: air pollutant emissions, ambient air concentrations and health indicators of the period 2009 to 2015. The emissions analysis, for the studied pollutants, pointed out the main findings: (i) Lisbon Metropolitan Area presents the most problematic region with regard to the emissions of all the pollutants under study; (ii) the regions of the Alentejo and Algarve showed reduced emissions of the studied pollutants compared to other parts of the country; (iii) Northern regions PM10 concentrations decreased during the two years in analysis. Regarding the analysis of air quality, it was concluded that: (i) regarding ozone, concentration shown a decreasing trend throughout the country; (ii) nitrogen dioxide and particulate matter, concentrations demonstrated an increasing trend in most of the northern part of the country; (iii) the regions of Alentejo and Lisbon Metropolitan Area showed increasing trends for sulfur dioxide and fine particles for the evaluated period. Decreasing trends in mortality associated with cardiovascular and respiratory causes are found mainly in the Alentejo and Algarve regions. In comparison, the North, Central regions, as well as, Lisbon Metropolitan Area exhibited higher mortality values related to this health indicators.
- Assessment of health benefits related to air quality improvement strategies in urban areas: An Impact Pathway ApproachPublication . Silveira, Carlos; Roebeling, Peter; Lopes, Myriam; Ferreira, Joana; Costa, Solange; Teixeira, João Paulo; Borrego, Carlos; Miranda, Ana I.Air pollution is, increasingly, a concern to our society given the threats to human health and the environment. Concerted actions to improve air quality have been taken at different levels, such as through the development of Air Quality Plans (AQPs). However, air quality impacts associated with the implementation of abatement measures included in AQPs are often neglected. In order to identify the major gaps and strengths in current knowledge, a literature review has been performed on existing methodologies to estimate air pollution-related health impacts and subsequent external costs. Based on this review, the Impact Pathway Approach was adopted and applied within the context of the MAPLIA research project to assess the health impacts and benefits (or avoided external costs) derived from improvements in air quality. Seven emission abatement scenarios, based on individual and combined abatement measures, were tested for the major activity sectors (traffic, residential and industrial combustion and production processes) of a Portuguese urban area (Grande Porto) with severe particular matter (PM10) air pollution problems. Results revealed a strong positive correlation between population density and health benefits obtained from the assessed reduction scenarios. As a consequence, potential health benefits from reduction scenarios are largest in densely populated areas with high anthropic activity and, thus, where air pollution problems are most alarming. Implementation of all measures resulted in a reduction in PM10 emissions by almost 8%, improving air quality by about 1% and contributing to a benefit of 8.8 million V/year for the entire study domain. The introduction of PM10 reduction technologies in industrial units was the most beneficial abatement measure. This study intends to contribute to policy support for decision-making on air quality management.
- Clinical impact of HFE Mutations in portuguese patients with Chronic Hepatitis CPublication . Ferreira, Joana; Baldaia, Cilénia; Inácio, Ângela; Bicho, Manuel; Velosa, José; Faustino, Paula; Serejo, FátimaINTRODUCTION: 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.
- Co-Inheritance of alpha-thalassemia and sickle cell disease in a cohort of Angolan pediatric patientsPublication . Santos, Brígida; Delgadinho, Mariana; Ferreira, Joana; Germano, Isabel; Miranda, Armandina; Faustino, Paula; Brito, MiguelThe aim of this study was to explore the association between alpha-thalassemia, fetal hemoglobin, hematological indices, and clinical adverse events in Angolan sickle cell disease pediatric patients. A total of 200 sickle cell disease (SCD) children were sampled in Luanda and Caxito. A venous blood sample was collected and used for hematological analyses, fetal hemoglobin quantification, and genotyping of 3.7 kb alpha-thalassemia deletion by GAP-PCR. The frequency of the 3.7 kb alpha-thalassemia deletion in homozygosity was 12.5% and in heterozygosity was 55.0%. An increase in alpha-thalassemia frequency was observed in children older than 5 years old (11.7% vs. 13.00%). Furthermore, 3.7 kb alpha-thalassemia deletion homozygotes had a significantly higher age of the first manifestation, lower number of blood transfusions by year, higher hemoglobin, lower mean corpuscular volume, mean corpuscular hemoglobin, and lower hemolytic rate observed by a lower number of reticulocytes count. There were no differences in fetal hemoglobin between the three genotypes. Moreover, the number of stroke events, osteomyelitis, splenomegaly, splenectomy, and hepatomegaly were lower when alpha-thalassemia was co-inherited. For the first time in Angolan population, the effect of alpha-thalassemia deletion in sickle cell disease was analyzed and results reinforce that this trait influences the hematological and clinical aspects and produces a milder phenotype.
- Contribution of HFE and HPSE genes and methaemoglobin reductase activity to heart failurePublication . Gaspar, Marcos A.; Aguiar, Laura; Ferreira, Joana; Faustino, Paula; Mascarenhas, Mário Rui; Menezes Falcão, Luiz; Bicho, Manuel; Inácio, ÂngelaIntroduction: Heart failure can be defined as a syndrome caused by a structural anomaly and/or by a committed cardiac function, which leads to an inadequate cardiac output unable to meet the metabolic necessities of the organism. We aim to understand if HFE and HPSE genes as well as methaemoglobin reductase activity, may influence the development of heart failure. Methodology: It was performed a case-control study, in which 252 DNA samples from Portuguese individuals were analysed, 143 derived from subjects with heart failure, and 109 from healthy controls. For HPSE genotyping (rs4693608), we performed endpoint PCR analysis. A multiplex ARMS (Amplification-Refractory Mutation System) assay was used for the simultaneous detection of two HFE polymorphisms (C282Y and H63D). Reductase methaemoglobin activity was determined by spectrophotometric methods. All statistical tests were performed with IBM® SPSS® Statistics 26.0 software. Statistical significance was defined as a p-value < 0.05. Results: Regarding the H63D polymorphism, results show the CG genotype as a risk factor [OR (95% CI) = 2.889 (1.041-8.018); p=0.042]. In what concerns HPSE gene, the GG genotype was found to have a protective effect [OR (95% CI) = 0.435 (0.193-0.982); p=0.045] while the presence of the A allele is a risk factor [OR (95% CI) = 2.297 (1.018-5.179); p=0.045. Considering methaemoglobin reductase, its activity was lower in patients than in healthy controls (p=0.019). Discussion: Intravenous iron supplementation is sometimes considered in heart failure treatment, emphasizing the results presented in the present study. Considering the high prevalence of heart failure in Portugal (400.000 individuals, according to Sociedade Portuguesa de Cardiologia), it is important to identify iron-related markers, since it may allow an earlier and more expert approach, which may provide better prevention and therapeutic strategies for this pathology.
- Contributo dos genes NOS e ECA para a suscetibilidade de elevar a glicemia em hipertensosPublication . Aguiar, Laura; Semente, Ildegário; Ferreira, Joana; Matos, Andreia; Mascarenhas, Mário Rui; Menezes Falcão, Luíz; Faustino, Paula; Bicho, Manuel; Inácio, ÂngelaIntrodução: A Hipertensão Arterial (HTA) é um fator de risco cardiovascular muito prevalente em Portugal. Esta patologia é multifatorial, envolvendo fatores genéticos e ambientais. A resistência à insulina e a hipertensão são componentes do síndroma metabólico e frequentemente coexistem. Níveis aumentados de glicemia associados a hipertensão aumentam significativamente o risco de doença cardiovascular. Objetivo: Este estudo teve como objetivo investigar a potencial implicação de polimorfismos genéticos nos genes da sintase do óxido nítrico endotelial (eNOS) e da enzima conversora da angiotensina (ECA) no desenvolvimento da HTA e hiperglicemia, na população portuguesa. Material e métodos: Foi realizado um estudo de caso-controlo para uma amostra de 377 indivíduos portugueses, dos quais 243 hipertensos e 134 normotensos. As análises polimórficas do número variável de repetições em tandem (VNTR) no intrão 4 (repetição em tandem de 27 pb) do gene eNOS e do polimorfismo ECA I/D (inserção/ deleção) foram realizadas por reação em cadeia da polimerase (PCR). Todas as análises estatísticas foram realizadas recorrendo ao software SPSS, versão 24.0, sendo o nível de significância estatística estabelecido para p <0,05. Resultados: Encontrou-se uma associação entre o alelo 4a do gene eNOS com a hipertensão (p =0,001), verificando-se ainda que na hipertensão, a presença do alelo 4a está associada a valores superiores de HbA1c (p=0,031). Em relação ao gene ECA, não se encontram diferenças estatisticamente significativas entre doentes e controlos, contudo verificou-se que a presença do alelo D em hipertensos está associada a níveis mais elevados de glicemia (p=0,017). Conclusão: Os nossos resultados mostram uma associação entre os genes eNOS e ECA com fenótipos clínicos associados a hiperglicemia, na população portuguesa. Indivíduos com níveis elevados de glicemia têm maior risco de desenvolver hipertensão. A identificação de polimorfismos genéticos que possam influenciar o desenvolvimento e gravidade da HTA, pode permitir um diagnóstico mais precoce e específico, que pode proporcionar melhores estratégias terapêuticas e de prevenção, para esta doença tão prevalente em Portugal.
- Diferenças genotípicas entre o sudoeste da Europa e África: um estudo comparativo em genes relacionados com a hipertensãoPublication . Aguiar, Laura; Semente, Ildegário; Carvalho, Andreia; Ferreira, Joana; Caria, Helena; Damasceno, Albertino; Faustino, Paula; Inácio, Ângela; Bicho, ManuelIntrodução: Desde o surgimento do género Homo, os hominídeos ocuparam uma grande variedade de ambientes com relação ao clima. Assim, espera-se que as pressões seletivas variem amplamente entre diferentes regiões geográficas. Objetivo: O objetivo do presente trabalho foi comparar a frequência genotípica em genes que têm sido propostos como potenciais moduladores da hipertensão arterial (HTA), uma doença multifatorial cujo contributo genético é importante, no sudoeste da Europa e em África. Os genes analisados foram: sintase do óxido nítrico endotelial (eNOS), glicose-6-fosfato desidrogenase (G6PD), alfa-globina (HBA) e enzima conversora da angiotensina (ECA). Material e métodos: Foram analisadas 224 amostras de DNA de Portugal e 202 amostras de África (24 amostras de DNA de Moçambique e 178 amostras de DNA de São Tomé e Príncipe). Para o gene eNOS, a análise polimórfica do número variável de repetições em tandem (VNTR) no intrão 4 (repetição em tandem de 27 pb) foi realizada por reação em cadeia da polimerase (PCR). A caracterização do SNP rs1050829 no gene G6PD foi obtida por PCR seguida de análise do comprimento do fragmento de restrição. Para a pesquisa da deleção α-talassémica de -3,7kb no agrupamento génico da α-globina foi usada uma metodologia de Gap-PCR. A genotipagem do polimorfismo da ECA I/D (inserção/ deleção) foi realizada por PCR. Todas as análises estatísticas foram realizadas recorrendo ao software SPSS, versão 24.0, sendo o nível de significância estatística estabelecido para p <0,05. Resultados: Os resultados mostram que, em relação ao gene eNOS, os genótipos que apresentam o alelo 4a (quatro cópias de repetições de 27 pb) têm uma frequência menor em Portugal do que em África (p <0,001). Curiosamente, apenas em África encontramos os alelos raros 4c, 4d e 4y. Para o gene G6PD (cromossoma X) há uma menor frequência dos genótipos com o alelo G em Portugal, comparado com a população africana (p <0,001). A presença da deleção α-talassémica de -3,7kb é comum em África, mas rara em Portugal (p <0,001). Em relação ao gene ECA, não se encontram diferenças estatisticamente significativas entre as populações estudadas (p =0,151). Conclusão: Os nossos resultados mostram diferenças na distribuição geográfica de três polimorfismos que potencialmente influenciam o desenvolvimento da HTA. Estas diferenças podem estar relacionadas com diferentes pressões seletivas proporcionadas pelos diferentes climas no sudoeste da Europa e na África equatorial e subequatorial. De facto, condições como o calor e a humidade estão associadas a maior perda de sódio.
- Differences in the genotype frequencies of genes related to blood pressure regulation - a comparative study between South-West Europe and Peri-equatorial AfricaPublication . Aguiar, Laura; Semente, Ildegário; Ferreira, Joana; Carvalho, Andreia; Silva, Alda P.; Caroça, Cristina; Caria, Helena; Damasceno, Albertino; Laires, Maria J.; Sardinha, Luís; Monteiro, Cristina; Mascarenhas, Mário R.; Faustino, Paula; Inácio, Ângela; Bicho, ManuelBackground: Since the emergence of the genus Homo, hominids have occupied a wide variety of environments, facing different selective pressures. Objectives: The aim this study is to compare genotype frequencies between South-West Europe and Peri-equatorial Africa in genes potentially modulators of blood pressure. Methods: The analyzed sample consisted of 325 individuals from Portugal and 226 individuals from Africa (48 from Mo zambique and 178 from São Tomé and Príncipe). The following genetic variants were analyzed: intron 4 VNTR in eNOS, rs1050829 in G6PD, -3.7kb α-thalassemic deletion in HBA, rs1800457 in CYB5R3, Hp 1/2 genotype/phenotype in Hp and intron 16 I/D in ACE. Results: Frequencies of genotypes with the 4a allele in eNOS (p<0.001), the G allele in G6PD (p<0.001), the α-3.7 kb in HBA (p <0.001), the C allele in the CYB5R3 (p<0.001) were higher in Peri-equatorial Africa. The Hp 1.1 genotype of Hp has a higher frequency in Peri-equatorial Africa (p=0.002). ACE shows no significant differences. Conclusion: Results show differences in five genetic variants. Conditions of extreme heat and humidity, characteristic of Peri-equatorial Africa, have been associated with increased sodium loss. This study suggests that selected compensatory mechanisms printed in the genome, are nowadays risk factors for hypertension in Peri-equatorial Africa.
- Effect of HCV clearence in hepatic disease and cardiometabolic profilePublication . Ferreira, Joana; Faustino, Paula; Bicho, Manuel; Serejo, FátimaThis study aimed to contribute to the knowledge of the changes in the severity of liver disease and in the cardiometabolic profile after HCV clearence, in order to optimize care.
- Estudo da interação entre moduladores da homeostasia do ferro e o gene ECA na insuficiência cardíacaPublication . Gaspar, Marcos A.; Aguiar, Laura; Ferreira, Joana; Faustino, Paula; Mascarenhas, Mário Rui; Menezes Falcão, Luís; Bicho, Manuel; Inácio, ÂngelaIntrodução: A insuficiência cardíaca (IC) diz respeito a um síndrome clínico composto por um conjunto de sintomas e/ou sinais com origem numa anomalia cardíaca estrutural e/ou funcional e que dá origem à inabilidade de bombear sangue em quantidade suficiente, de forma a preencher as necessidades metabólicas do organismo. No presente trabalho, pretendemos perceber como a interação entre a variação I/D no gene ECA e possíveis moduladores da homeostasia do ferro (Fe) influenciam a IC. Os moduladores em estudo foram: a atividade da redutase da metahemoglobina, o gene Hfe e o gene da heparanase (HPSE) Metodologia: Foi efetuado um estudo de caso-controlo, no qual foram utilizadas 252 amostras de portugueses, 143 indivíduos com IC e 109 controlos saudáveis. Para analisar o polimorfismo no gene HPSE (rs4693608) foi feita a genotipagem por endpoint (LightCycler480). Para analisar os polimorfismos no gene Hfe (H63D e C282Y) recorreu-se à técnica de ARMS Multiplex. Para a análise do polimorfismo no gene ECA (rs4646994 - I/D) realizou-se um PCR. A atividade da redutase da metahemoglobina foi obtida por testes espetrofotométricos. Todos os testes estatísticos necessários foram realizados no software IBM® SPSS® Statistics 26.0, tendo os valores sido considerados significativos para um p < 0,05. Resultados: Verificou-se uma associação entre a IC e: 1) a presença do alelo D do gene HFe (HH vs HD; p=0,049); 2) a presença do alelo A do gene HPSE (AA + GA vs GG; p=0,045; 3) níveis mais baixos da atividade da redutase da metahemoglobina (p=0.019). Verificou-se ainda que as epistasias entre a presença do alelo H ou C do gene Hfe e o alelo D do gene ECA são protetores na IC (p=0,041 para ambas). Conclusão: Os resultados deste estudo evidenciam o papel da homeostasia do ferro e da sua interação com a ECA na IC. O ferro é um componente essencial para o bom funcionamento das mitocôndrias, as quais têm um papel importante no fornecimento de energia ao musculo cardíaco. O conhecimento do perfil genótipo dos doentes em genes moduladores da homeostasia do ferro em interação com o gene ECA, poderá ser uma vantagem na aplicação de uma medicina mais personalizada, permitindo um aconselhamento preventivo e uma terapêutica mais dirigidos.