Genotoxic effects in occupational exposure to formaldehyde: A study in anatomy and pathology laboratories and formaldehyde-resins production

ABSTRACT – Background: According to the Report on Carcinogens, formaldehyde ranks 25th in the overall U.S. chemical production, with more than 5 million tons produced each year. Given its economic importance and widespread use, many people are exposed to formaldehyde environmentally and/or occupationally. Presently, the International Agency for Research on Cancer classifies formaldehyde as carcinogenic to humans (Group 1), based on sufficient evidence in humans and in experimental animals. Manyfold in vitro studies clearly indicated that formaldehyde can induce genotoxic effects in proliferating cultured mammalian cells. Furthermore, some in vivo studies have found changes in epithelial cells and in peripheral blood lymphocytes related to formaldehyde exposure. Methods: A study was carried out in Portugal, using 80 workers occupationally exposed to formaldehyde vapours: 30 workers from formaldehyde and formaldehyde-based resins production factory and 50 from 10 pathology and anatomy laboratories. A control group of 85 non-exposed subjects was considered. Exposure assessment was performed by applying simultaneously two techniques of air monitoring: NIOSH Method 2541 and Photo Ionization Detection equipment with simultaneously video recording. Evaluation of genotoxic effects was performed by application of micronucleus test in exfoliated epithelial cells from buccal mucosa and peripheral blood lymphocytes. Results: Time-weighted average concentrations not exceeded the reference value (0.75 ppm) in the two occupational settings studied. Ceiling concentrations, on the other hand, were higher than reference value (0.3 ppm) in both. The frequency of micronucleus in peripheral blood lymphocytes and in epithelial cells was significantly higher in both exposed groups than in the control group (p < 0.001). Moreover, the frequency of micronucleus in peripheral blood lymphocytes was significantly higher in the laboratories group than in the factory workers (p < 0.05). A moderate positive correlation was found between duration of occupational exposure to formaldehyde (years of exposure) and micronucleus frequency in peripheral blood lymphocytes (r = 0.401; p < 0.001) and in epithelial cells (r = 0.209; p < 0.01). Conclusions: The population studied is exposed to high peak concentrations of formaldehyde with a long-term exposure. These two aspects, cumulatively, can be the cause of the observed genotoxic endpoint effects. The association of these cytogenetic effects with formaldehyde exposure gives important information to risk assessment process and may also be used to assess health risks for exposed worker

A diabetes: principais parâmetros para o controlo da diabetes

RESUMO: A Diabetes Mellitus é uma doença metabólica crónica, com deficiência a nível do metabolismo dos hidratos de carbono, lípidos e proteínas, resultante de deficiências na secreção ou ação da insulina, ou de ambas, que quando não tratada antecipadamente e de modo conveniente, pode ter consequências muito graves. Dado a incidência a nível mundial da Diabetes Mellitus, torna-se de elevada importância avaliar toda a sua envolvência e estudar bem quais os critérios a ter em consideração. Este trabalho propõe-se estudar para além dos parâmetros bioquímicos relacionados com a doença - Glicose e Hemoglobina Glicada A1c (HbA1c), analisar os resultados dos últimos cinco anos (2008-2012) dos ensaios interlaboratoriais do PNAEQ, do Departamento de Epidemiologia, do Instituto Nacional de Saúde Dr. Ricardo Jorge. Foram também analisadas as metodologias utilizadas e as variações interlaboratoriais, de forma a entender qual ou quais são os parâmetros mais adequados para o seu diagnóstico e controlo. Este estudo utilizou a população de laboratórios portugueses, públicos e privados, de Portugal Continental e Ilhas, um laboratório de Angola e outro de Macau que se inscreveram no PNAEQ nestes cinco anos, sendo a amostra composta pelo n.º de participações. No programa de Química Clinica foram distribuídas 38 amostras e no programa de HbA1c foram distribuídas 22 amostras. Para a glicose, o nível de desempenho nos ensaios é na globalidade das amostras de Excelente, no entanto verifica-se que sempre que a concentração da amostra é de nível patológico, que a maioria dos ensaios o desempenho foi inferior – Bom. O método de eleição e com CV% mais baixos foi o método da hexoquinase. Para a HbA1c, o nível de desempenho nos ensaios é na globalidade das amostras de Excelente. O método de eleição e com CV% mais baixos foi o método de HPLC. O CV% para a glicose ronda desde 2010 a 2012, os 3% e para a HbA1c foi de aproximadamente 4,0% em 2012. A HbA1c tem mostrado ser uma ferramenta muito útil, importante e robusta na monitorização da Diabetes, sendo hoje em dia quase sempre requisitada em análises de rotina a diabéticos de modo a prevenir complicações que possam vir a acorrer. No futuro poderá ser um importante, senão o parâmetro de futuro, para o diagnóstico da Diabetes, no entanto, mesmo já tendo sido muito trabalhada a sua padronização, ainda existem questões por responder como quais são na realidade todos os seus interferentes, qual a verdadeira relação da HbA1c com a glicose média estimada, em todas as populações e com estudos epidemiológicos. Também a própria educação do diabético e clínico deve ser aprimorada, pelo que neste momento as PTGO e os doseamentos de glicose em jejum devem ser utilizados e encontrando-se a Norma da DGS N.º 033/2011 de acordo com as necessidades e com o estado da arte deste parâmetro. A implementação da glicose média estimada será uma mais-valia na monitorização dos diabéticos pelo que deverá ser uma das prioridades a ter em conta no futuro desta padronização, uniformizando a decisão clinica baseada nela e minimizando a dificuldade de interpretação de resultados de laboratório para laboratório. --------------ABSTRACT: Diabetes Mellitus is a chronic metabolic disease, with a deficit in the metabolism of carbohydrates, lipids and proteins, resulting from deficiencies in insulin secretion or action, or both, which if, when not early treated in a proper way, may result in very serious consequences. Given the worldwide incidence of diabetes mellitus, it is highly important to evaluate all its background and study specifically all the criteria to take into consideration. The aim of this thesis is to study and evaluate beyond the biochemical parameters related to the disease - Glucose and Glycated Haemoglobin A1c (HbA1c), analyze the results of the last five years (2008-2012) of the PNAEQ interlaboratorial tests, in the Department of Epidemiology of National Institute of Health Dr. Ricardo Jorge. It is also intended to analyze the methodologies used and the interlaboratorial variations, in order to understand the most suitable parameters for the diagnosis and control. This study was based in a population of Portuguese laboratories, public and private, of Portugal mainland and islands, a laboratory of Angola and other from Macau, who enrolled in PNAEQ in these five years, and the sample was composed by the n. º of holdings. In the Clinical Chemistry Program there were distributed 38 samples and in the program HbA1c were distributed 22 samples. For glucose, the level of performance in the total nº of the samples was Excellent; however, it was found that when the concentration level of the sample was pathological, in most of the tests the performance was Good. The most preferred method with the lowest CV% is the hexokinase method. For the HbA1c, as a whole, the samples’ tests were Excellent, at the level of performance. The method of election with the lower CV% was the HPLC. The CV% for glucose was around 3%, from 2010 to 2012 and the HbA1c was approximately 4.0% in 2012. The HbA1c method has demonstrated to be a very useful tool, important and robust for monitoring diabetes, being nowadays, almost always required in routine analysis to prevent future complications. In the future it may be an important parameter, if not the most important, for the diagnosis of diabetes. However, despite it has already been standardized, there are still some questions that need to be answered, such as, which are in fact all their interferences, which is the true connection of HbA1c, when compared with the estimated average glucose, in all populations and epidemiological studies. Moreover, the education of the patient and the doctor concerning diabetes should be improved. Nowadays, the Oral Glucose Tolerance Test (OGTT) and fasting glucose determinations should be used and, the needs and the state of the art of this parameter, should be in accordance with the Standard DGS N. º 033/2011. The Implementation of the estimated average glucose will be an added value in monitoring diabetics and, therefore, should be a priority to consider in its future standardization and clinical decision based on it, will be uniform and the difficulty of interpreting results from laboratory to laboratory will be minimal.

Dependence of IVIM-DWI estimations on acquisition parameters

Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica

Safe reuse of treated urban wastewater in Praia, Cape Verde: a case study

Dissertação para a obtenção do Grau de Mestre em Engenharia e Gestão da Água

Landscape composition and climatic parameters significant in the spread of an invasive species (Pine wood Nematode)

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente

Sustainable urban planning: parameters to the operational process

In modern society, energy consumption and respect for the environment have become essential aspects of urban planning. The rising demand for alternative sources of energy, coupled with the decline in the construction sector and material usage, gives the idea that the thinking on modern cities, where attention is given to reduced energy consumption, savings, waste recycling and respect for the surrounding environment, is being put into practice. If we examine development of the city over recent centuries, by means of the theories of the most famous and influential urban planners, it is possible to identify the major problems caused by this type of planning. For this reason, in recent urban planning the use of systems of indicators that evaluate and certify land environmentally and energetically guides the master plan toward a more efficient city model. In addition the indicators are targeted on key factors determined by the commissioner or the opportunities the territory itself provides. Due the complexity of the environmental mechanics, the process of design and urban planning has become a challenging issue. The introduction of the indicators system has made it possible to register the life of the process, with a spiral route that allows the design itself to be refined. The aim of this study, built around the creation of a system of urban sustainability indicators that will evaluate highly eco-friendly cities, is to develop a certification system for cities or portions of them. The system will be upgradeable and objective, will employ real data and will be concerned with energy production and consumption.

Control of a white organic light emitting diode’s emission parameters using a single doped RGB active layer

White Color tuning is an attractive feature that Organic Light Emitting Diodes (OLEDs) offer. Up until now, there hasn’t been any report that mix both color tuning abilities with device stability. In this work, White OLEDs (W-OLEDs) based on a single RGB blend composed of a blue emitting N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) doped with a green emitting Coumarin-153 and a red emitting 4-(Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM1) dyes were produced. The final device structure was ITO/Blend/Bathocuproine (BCP)/ Tris(8-hydroxyquinolinato)aluminium (Alq3)/Al with an emission area of 0.25 cm2. The effects of the changing in DCM1’s concentration (from 0.5% to 1% wt.) allowed a tuning in the final white color resulting in devices capable of emitting a wide range of tunes – from cool to warm – while also keeping a low device complexity and a high stabilitty. Moreover, an explanation on the optoelectrical behavior of the device is presented. The best electroluminescense (EL) points toward 160 cd/m2 of brightness and 1.1 cd/A of efficiency, both prompted to being enhanced. An Impedance Spectroscopy (IS) analysis allowed to study both the effects of BCP as a Hole Blocking Layer and as an aging probe of the device. Finally, as a proof of concept, the emission was increased 9 and 64 times proving this structure can be effectively applied for general lighting.