Browsing by Author "Veiga, Luisa"
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- Assessment of workers’ exposure to Aflatoxin B1 in a Portuguese waste industryPublication . Viegas, Susana; Veiga, Luisa; Figueredo, Paula; Almeida, Ana; Carolino, Elisabete; Viegas, CarlaAflatoxin B1 (AFB1) is considered by different International Agencies as a genotoxic and potent hepatocarcinogen. However, despite the fact that the fungi producing this compound are detected in some work environments, AFB1 is rarely monitored in occupational settings. The aim of the present investigation was to assess exposure to AFB1 of workers from one Portuguese waste company located in the outskirt of Lisbon. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Forty-one workers from the waste company were enrolled in this study (26 from sorting; 9 from composting; 6 from incineration). A control group (n = 30) was also considered in order to know the AFB1 background levels for the Portuguese population. All the workers showed detectable levels of AFB1 with values ranging from 2.5ng ml−1 to 25.9ng ml−1 with a median value of 9.9±5.4ng ml−1. All of the controls showed values below the method’s detection limit. Results obtained showed much higher (8-fold higher) values when compared with other Portuguese settings already studied, such as poultry and swine production. Besides this mycotoxin, other mycotoxins are probably present in this occupational setting and this aspect should be taken into consideration for the risk assessment process due to possible synergistic reactions. The data obtained suggests that exposure to AFB1 occurs in a waste management setting and claims attention for the need of appliance of preventive and protective safety measures.
- Blood pressure and its circadian pattern in obese and lean premenopausal womenPublication . Silva-Nunes, José; Brito, Miguel; Veiga, LuisaBackground: Obesity is frequently referred to as an independent risk factor for high blood pressure and hypertension is very prevalent among obese people. The aims of this study were: to compare office-based and 24 h blood pressure (BP) and its circadian pattern between lean and obese women; to study correlations between BP, insulin resistance (IR), and markers of subclinical inflammation/early atherosclerosis. Material and methods: Eighty-eight lean and 107 otherwise healthy obese women were characterized for anthropometrics, BP (office-based determinations and 24 h ABPM), and for glucose, insulin, triglycerides, interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-a), high-sensitivity C reactive protein (hs-CRP), retinol-binding protein 4 (RBP-4), leptin, adiponectin, resistin, monocyte chemoattractant protein 1 (MCP-1), intercellular adhesion molecule 1 (ICAM-1), and vascular-cellular adhesion molecule 1 (VCAM-1). Insulin resistance was determined by homeostasis model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), and McAuley indexes (also Matsuda in obese). Results: The obese group presented higher office-based systolic/diastolic BP, systolic ambulatory blood pressure monitoring (ABPM), and more non-dippers. HOMA-IR and body fat was correlated to systolic (r2 = 0.176) and glucose to diastolic (p = 0.008; r = 0.256) ABPM. Age, QUICKI, and TNF-a was correlated with dipping (r2 = 0.172); adiponectin, age, BMI, and glucose to systolic (r2 = 0.226) and diastolic (r2 = 0.215) office-based BP. Concerning lean women, MCP-1 was associated with diastolic ABPM (p = 0.013; r = 0.267). Systolic office-based BP was associated with waist-to-hip ratio (p = 0.01; r = 0.273); this and RBP-4 was correlated with office-based diastolic BP (r2 = 0.12). Conclusion: Although relatively healthy, obese women present higher BP than lean. Anthropometrics, IR, and fasting glucose all influence BP in obesity; additionally, IR is involved in non-dipping. No strong correlation exists between BP/dipping and subclinical inflammation in either group of women.
- Os cílios primários regulam os níveis de tiorredoxina redutase 1 e de yH2AX em resposta a níveis elevados de glucosePublication . Marques, Rira; Paiva, Mariana; Ginete, Catarina; Nolasco, Sofia; Marinho, Susana H.; Veiga, Luisa; Brito, Miguel; Soares, Helena; Carmona, BrunoA diabetes caracteriza-se por uma anormal capacidade de controlar o nível de glucose na corrente sanguínea, podendo levar a outras complicações, tais como hipertensão, doenças cardiovasculares, e retinopatia. A desregulação dos níveis de glucose na retina tem demonstrado aumentar os níveis de peróxido de hidrogénio, conduzindo a uma rutura na barreira sanguínea da retina, uma das causas de retinopatia diabética. O cílio primário é um organelo que demonstrou ter um papel no controlo do equilíbrio energético e da homeostase da glucose. Defeitos na estrutura e função dos cílios podem resultar no desenvolvimento de várias doenças, conhecidas como ciliopatias, e que incluem fenótipos como obesidade e diabetes. Neste trabalho pretendemos estudar o papel do aumento dos níveis de glucose na montagem de cílios primários em culturas de células do epitélio pigmentar da retina (RPE-1), bem como o papel dos cílios na resposta celular aos níveis elevados de glucose. Para isso, suplementámos os meios de crescimento das células RPE-1 com diferentes concentrações de glucose (5 mM, 25 mM e 5 mM de glucose + 20 mM manitol). Estas células também foram induzidas a montar cílios antes ou depois da suplementação com a glucose. Neste estudo observámos que a suplementação de glucose não afetou o número de células ciliadas, sendo que o comprimento dos cílios foi menor em células suplementadas com 25 mM de glucose. Também avaliámos os níveis nucleares de tiorredoxina redutase 1 (TXNRD1), uma das principais enzimas intervenientes na resposta ao stress oxidativo desencadeado pela hiperglicemia, e de γH2AX, um marcador celular de quebras no DNA e de senescência celular. Observámos que os níveis nucleares de TXNRD1 e de γH2AX são afetados pela adição de glucose e que a existência de cílios modula a resposta das células em resposta a níveis elevados de glucose. Estes resultados mostram que a presença de cílios primários afeta drasticamente a resposta celular às elevadas concentrações de glucose que provavelmente induzem o stress oxidativo, podendo ter um papel crucial no desenvolvimento de retinopatia diabética.
- Depressive symptomatology, temperament and oxytocin serum levels in a sample of healthy female university studentsPublication . Veiga, Luisa; Carolino, Elisabete; Santos, I.; Veríssimo, C.; Almeida, Ana; Grilo, Ana Monteiro; Brito, Miguel; Santos, Margarida Custódio dosBackground: Depressive symptomatology is prevalent among female university students with adverse effects on their quality of life and academic performance. Previous research suggested associations between depressive symptomatology and oxytocin levels and between depressive symptomatology and Temperament Traits. Despite this evidence, to the best of our knowledge, no research has studied the effects of both oxytocin serum levels and temperament dimensions on depressive symptoms in a healthy sample. The present study aimed to analyze the effect of oxytocin levels and temperament traits on depressive symptomatology in healthy female university students. Methods: All participants completed the Beck Depression Inventory and the Adult Temperament Questionnaire. Blood samples were collected between 8 and 8H30 a.m. after 12 h of fasting and between 5 and 8 days of the menstrual cycle and serum oxytocin levels were quantified using a commercial enzyme-linked immunosorbent assay. A hierarchical multiple regression model using a stepwise method was conducted to identify predictors of depression. Results: Forty-five women aged between 18 and 25 years old (19.37 ± 1.32 years) volunteered to participate in this study. Depressive symptomatology was negatively associated with oxytocin serum levels and "Negative affect" and positively associated with "Effortful control" and "Activation Control". In the final regression model, only oxytocin level was a predictor (B = - 0.090, p < 0.0001), the model explaining 65.2% of the depression variation. Oxytocin played a mediation role between "Negative effects" and Depressive symptomatology. Conclusions: Our results showed that oxytocin level, rather than personality dimensions, was associated with depressive symptomatology. These results highlight the relevance of the discussion on the use of oxytocin as a biological marker of emotional and social symptoms that characterize depression.
- Differential expression of adhesion molecules in sickle cell anemia and gut microbiome effectPublication . Delgadinho, Mariana; Veiga, Luisa; Ginete, Catarina; Santos, Brígida; Miranda, Armandina; Vasconcelos, Jocelyne Neto de; Brito, MiguelSickle cell anemia (SCA) causes a long-standing vascular inflammation state, leading to endothelial dysfunction and chronic overexpression of several adhesion molecules, which contributes to acute and constant vaso-occlusive (VOC) episodes. It has been demonstrated that hydroxyurea (HU) can reduce VOC events, organ damage, blood transfusions, and even the adhesion properties to endothelial cells of SCA subjects. Due to VOC episodes, these patients are also more susceptible to recurrent bacterial translocation and dysbiosis. Given this, our study aimed to uncover the interplay between adhesion molecules, gut microbiome, and hydroxyurea in a population of Angolan SCA children. Serum and fecal samples were obtained before and after HU treatment in 35 children. After HU, four of these adhesion molecules were significantly reduced: sE-selectin (p = 0.002), ADAMTS13 (p = 0.023), sICAM-1 (p = 0.003), and sVCAM-1 (p = 0.018). A positive correlation was observed between the number of neutrophils and sICAM-1, platelets, and sP-selectin, and also between leukocytes, sICAM-1, and sVCAM-1. Most taxa showing a significant correlation mainly belonged to the Clostridiales order. Specifically, from the Clostridium genera, the groups g19, g21, and g34 were all negatively correlated with HbF levels; g19, g21, and g24 positively correlated with leukocytes; g19 positively with neutrophils and sVCAM-1; and g34 positively with E- and P-selectin. Serratia, an opportunistic pathogen, was positively correlated with sE-selectin and sICAM-1 levels. Additionally, a negative correlation was observed between sP-selectin and Bifidobacterium. Research studies in this area could improve our understanding and contribute to finding new prognostic biomarkers to guarantee precise SCA patient stratification and predict severe complications.
- Glucose homeostasis in obese women is not associated to unacylated ghrelin plasma levelsPublication . Veiga, Luisa; Brito, Miguel; Silva, Carina; Silva-Nunes, JoséIntroduction: Unacylated ghrelin (UAG) is the major form of circulating ghrelin. Initially considered as a nonfunctional peptide, soon after, UAG has been associated with an insulin-sensitizing action and to negative action on energy balance. The aim of this study was to analyze the association between the serum levels of UAG and glucose metabolism parameters in obese women, independently from the eventual influence of anthropometrics. Methods: One hundred lean and 254 obese Caucasian women were studied. Each woman was characterized by anthropometrics, fasting glucose, insulin, HbA1c, and UAG. In addition, obese women were subjected to a classic oral glucose tolerance test (oGTT) to assess glucose and insulin at 120 minutes. Insulin resistance was assessed by the homeostasis model assessment (HOMA-IR). Obese women were classified into three glycemic status subgroups (normoglycemia, prediabetes, and diabetes) according to HbA1c and fasting, and oGTT glucose values. Results: In comparison with the lean group, significantly lower levels of UAG were observed in obese women. However, no significant difference was observed through obesity classes I to III. UAG levels were not significantly different among glycemic status subgroups and did not show any association with glucose, insulin, HOMA-IR, or HbA1c. Conclusions: Although anthropometry can influence the level of the unacylated form of ghrelin, UAG plasma levels do not associate with glucose homeostasis parameters.
- Identification of genetic variants in 65 obesity related genes in a cohort of Portuguese obese individualsPublication . Ginete, Catarina; Serrasqueiro, Bernardo; Silva-Nunes, José; Veiga, Luisa; Brito, MiguelObesity is a major public health problem, which has a strong genetic component that interplays with environmental factors. Several genes are known to be implicated in the regulation of body weight. The identification of alleles that can be associated with obesity is a key element to control this pandemic. On the basis of a Portuguese population, 65 obesity-related genes are sequenced using Next-Generation Sequencing (NGS) in 72 individuals with obesity, in order to identify variants associated with monogenic obesity and potential risk factors. A total of 429 variants are identified, 129 of which had already been associated with the phenotype. Comparing our results with the European and Global frequencies, from the 1000 Genomes project, 23 potential risk variants are identified. Six new variants are discovered in heterozygous carriers: four missense (genes ALMS1-NM_015120.4:c.5552C>T; SORCS1-NM_001013031.2:c.1072A>G and NM_001013031.2: c.2491A>C; TMEM67-NM_153704.5:c.158A>G) and two synonymous (genes BBS1-NM_024649.4:c.1437C>T; TMEM67-NM_153704.5:c.2583T>C). Functional studies should be performed to validate these new findings and evaluate their penetrance and pathogenicity. Regardless of no cases of monogenic obesity being identified, this kind of investigational study is important when we are still trying to understand the etiology and pathophysiology of obesity. This will allow the identification of rare variants associated with obesity and the study of their prevalence in specific populational groups.
- A implementação de um rastreio neonatal de doença das células falciformes em Angola: apoio à formação de técnicos de saúde no âmbito da cooperação Portugal-AngolaPublication . Brito, Miguel; Ginete, Catarina; Inusa, Baba; Mendes, Manuela; Vasconcelos, Jocelyne Neto; Veiga, LuisaIntrodução: A doença das células falciformes (DCF) é uma doença hereditária severa, com uma incidência especialmente elevada na África subsariana, sendo responsável por 50% da mortalidade em crianças com menos de 5 anos. A prevalência desta doença genética em Angola ronda os 2%, sendo a doença genética mais frequentes no mundo. A identificação da doença à nascença permite o seguimento das crianças em consultas especializadas reduzindo assim a mortalidade e morbilidade infantil. Objetivos: Implementação de um Rastreio neonatal em Luanda para diagnóstico de DCF, com treino na recolha e análise de amostras bem como apoio no follow up dos pacientes e redução da taxa de mortalidade abaixo dos 5 anos. Pretende-se ainda avaliar os custos da implementação do rastreio neonatal, bem como avaliar o impacto financeiro do diagnóstico precoce. Contexto: O nosso objetivo é a implementação do Rastreio Neonatal no Hospital Materno Infantil Dr. Manuel Pedro Azancot de Menezes, Luanda. Pretendemos realizar Treino in loco dos profissionais de saúde (técnicos de laboratório, médicos, enfermeiros e auxiliares de saúde) no processo de recolha de amostras e de dados, bem como, na deslocação de técnicos de Laboratório a Lisboa para formação na técnica de electroforese de hemoglobinas por focagem isoeléctrica no equipamento Migele (adquirido com o apoio da Perkin Elmer e do projeto ARISE). Os estágios em Lisboa estão integrados no projeto “ARISE- African Research and Innovative Initiative for Sickle cell Education”, financiado pela União Europeia no programa Marie Skłodowska-Curie Actions. Pretende-se que no futuro todo o processo relativo ao rastreio neonatal seja assegurado em Luanda pelos técnicos formados no nosso laboratório.
- Influence of a movement program on mobility in very elderly individuals: a quasi-experimental studyPublication . Gonçalves, Ana Carolina; Veiga, Luisa; Tomás, Maria TeresaIntroduction - Worldwide, the population is increasingly aged, with a steady increase in average life expectancy. The regular practice of physical exercise is known as a beneficial factor in the aging process and for the maintenance of physical fitness. Purpose - To verify the influence of a movement program in very elderly participants living in a nursing home and daycare center (aged over 75 years) on their grip strength, lower limb strength, and mobility.
- Ressonância magnética no estudo do Locus coeruleus e a relação com o processo cognitivo de atenção: revisão sistemáticaPublication . Bulhões, Margarida; Ribeiro, Maria Margarida; Veiga, LuisaIntrodução: A degeneração progressiva dos neurónios do Locus Coeruleus associada à diminuição de recetores adrenérgicos, alvos da Noradrenalina, conduz a uma diminuição da função cerebral, provocando uma baixa resposta hemodinâmica e atividade neuronal. A disfunção noradrenérgica pode, ainda, interromper a capacidade de monitorizar estímulos externos e alterar o processo cognitivo da atenção, como acontece na Doença de Alzheimer e na Doença de Parkinson. Objetivos: A investigação procurou unir estudos estruturais e funcionais do Locus Coeruleus, incluindo estudos pupilométricos na avaliação da atenção seletiva visual, que atendessem à resposta cerebral bem como à progressão da doença, com a finalidade de correlacionar o processo cognitivo de atenção com a imagem obtida por Ressonância Magnética do Locus Coeruleus. Materiais e Métodos: A estratégia de pesquisa foi desenvolvida para encontrar todos os potenciais artigos relevantes num conjunto de fontes, como: as bases de dados bibliográficas de biomedicina; bases de registos de ensaios clínicos randomizados e quase randomizados; repositórios científicos e sites agregadores de bases bibliográficas. Resultados: Estudos que avaliaram o Locus Coeruleus por Ressonância Magnética demonstram variações morfológicas dependentes da idade e estudos funcionais, juntamente com testes pupilométricos, apresentaram alterações na neuromodulação percutindo-se na seletividade da atenção. Conclusão: A compilação da análise dos estudos forneceu dados para o estudo do Locus Coeruleus e a relação com o processo cognitivo de atenção. Cientificamente, todos os aspetos morfológicos e funcionais sugerem possibilitar a análise da disfunção noradrenérgica sob o campo da imagem de Ressonância Magnética para compreender a incapacidade do Locus Coeruleus em monitorizar estímulos externos e alterar o processo cognitivo da atenção.