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A gasolina é uma mistura complexa de substâncias, dentre elas estão hidrocarbonetos como o benzeno, tolueno, etilbenzeno e xilenos (BTEX), sendo esses compostos emitidos para a atmosfera, com destaque ao benzeno, por ser comprovadamente carcinogênico. Objetivamos avaliar as concentrações de BTEX no ar de postos de revenda de combustíveis no Município do Rio de Janeiro, Brasil, e calcular o risco de câncer associado a estas exposições. Foram realizados dois tipos de amostragem (fixa e móvel) adaptadas da metodologia nº 1.501 do Instituto Nacional de Segurança e Saúde Ocupacional (Estados Unidos), em seis postos de revenda de combustíveis na Zona Oeste da cidade. A amostragem fixa foi feita próxima às bombas de combustível, enquanto a móvel foi realizada através da coleta do ar na zona respiratória dos trabalhadores (frentistas), conforme estes se deslocavam pelo posto. As amostras foram analisadas por cromatografia gasosa com detecção por ionização em chama. Com os resultados das amostragens foram feitos os cálculos de risco à saúde, usando os indicadores Quociente de perigo (HQ) e Risco de câncer (CR), para avaliar os possíveis efeitos não-carcinogênicos e carcinogênicos, respectivamente, nos trabalhadores dos postos de revenda de combustíveis. As concentrações ambientais para a maioria dos compostos BTEX foram abaixo dos limites preconizados, menos para o benzeno, um composto carcinogênico, que apresentou concentrações muito acima dos limites, levando a altos valores de risco de câncer. Os resultados demonstraram que há riscos à saúde dos trabalhadores de postos de revenda de combustíveis, principalmente o risco de desenvolver câncer, devido à exposição excessiva ao benzeno. Gasoline is a complex mixture of substances, including aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylenes (BTEX). These compounds are emitted into the air, with the special relevance of benzene since it is provenly carcinogenic. The study aimed to assess BTEX concentrations in filling stations in the city of Rio de Janeiro, Brazil, and to calculate the cancer risk associated with such exposures. Two types of sampling were performed (stationary and mobile), adapted from methodology n. 1,501 (U.S. National Institute for Occupational Safety and Health) for aromatic hydrocarbons, in six filling stations in the West Zone of Rio de Janeiro. Stationary sampling was done near the fuel pumps, while mobile sampling was done in the breathing zone of the workers (station attendants) as they moved around the station. The samples were analyzed with gas chromatography flame ionization detector. The sampling results were used to calculate the health risk, using the indicators Hazard quotient (HQ) and Cancer risk (CR) to assess the possible non-carcinogenic and carcinogenic effects, respectively, in filling station workers. Environmental concentrations for the most of the BTEX compounds were below the recommended limits, except for benzene, a carcinogenic compound, which displayed concentrations far above the limits, leading to high cancer risk values. The results showed that there are health risks for filling station attendants, especially the risk of developing cancer from excessive exposure to benzene. La gasolina es una mezcla compleja de sustancias, entre ellas existen hidrocarburos como el benceno, tolueno, etilbenceno y xilenos (BTEX), emitiéndose estos compuestos a la atmósfera, donde se destaca el benceno, al tratarse de un carcinogénico comprobado. Los objetivos fueron evaluar las concentraciones de BTEX en el aire de puestos de reventa de combustibles, en el municipio de Río de Janeiro, Brasil, así como calcular el riesgo de cáncer asociado a estas exposiciones. Se realizaron dos tipos de muestra (fija y movible), adaptadas de la metodología nº 1.501 del Instituto Nacional de Seguridad y Salud Laboral (EE.UU.), en seis puestos de reventa de combustibles de la zona oeste de la ciudad. La muestra fija se realizó cerca de las bombas de combustible, mientras que la móvil se hizo mediante tomas de aire en la zona respiratoria de los trabajadores (de la gasolinera), a medida que estos se desplazaban por el lugar de trabajo. Las muestras se analizaron por cromatografía gaseosa con detección por ionización en llama. Junto a los resultados de las muestras, se realizaron cálculos de riesgo para la salud, usando los indicadores Cociente de peligro (HQ) y Riesgo de cáncer (CR), con el fin de evaluar los posibles efectos no-carcinogénicos y carcinogénicos, respectivamente, en los trabajadores de los puestos de reventa de combustibles. Las concentraciones ambientales para la mayoría de los compuestos BTEX estuvieron por debajo de los limites preconizados, menos en el caso del benceno, un compuesto carcinogénico, que presentó concentraciones muy por encima de los límites, llevando a altos valores de riesgo de cáncer. Los resultados demostraron que existen riesgos para la salud de los trabajadores de puestos de reventa de combustibles, principalmente, riesgo de desarrollar cáncer, debido a la exposición excesiva al benceno.

RESUMO Nas últimas décadas se intensificou o lançamento, no meio hídrico, de contaminantes com capacidade de desregulação endócrina. Nesse contexto, a aplicação e o aprimoramento de métodos analíticos eficientes passam a ser cada vez mais requeridos para verificar os potenciais impactos dessas substâncias sobre os organismos a elas expostos. Bioensaios podem ser conduzidos para esse fim, como, por exemplo, o ensaio in vitro yeast estrogen screen (YES), que permite a detecção de compostos estrogênicos e citotóxicos. Este estudo, aplicando tal ensaio, investigou a atividade estrogênica das águas e seus potenciais riscos à biota aquática de dois corpos hídricos do município de Santa Maria Madalena, no estado do Rio de Janeiro, Sudeste do Brasil. Observou-se atividade estrogênica apenas no córrego São Domingos, com concentrações de equivalente estradiol (EQ-E2) de 23 e 10.4 ng.L−1 no período de estiagem e chuvoso, respectivamente. Os potenciais riscos desse nível de atividade estrogênica foram mensurados por meio de uma avaliação de risco, que revelou alto e médio risco nas estações seca e chuvosa, respectivamente. Cabe mencionar que, entre os corpos hídricos estudados, a área do córrego São Domingos é aquela com maior adensamento populacional e menor cobertura de coleta e tratamento de esgotos. O ensaio YES mostrou ser uma boa ferramenta para a detecção da presença de desreguladores endócrinos estrogênicos, que pode subsidiar o avanço do conhecimento de corpos hídricos e a formulação de legislação e regulamentações da área ambiental. ABSTRACT In recent decades, the release of contaminants with endocrine disrupting capacity into the water environment has intensified. In this context, the application and improvement of efficient analytical methods are increasingly required to verify the potential impacts of these substances on the organisms exposed to them. Bioassays can be conducted with this purpose, such as the yeast estrogen screen (YES) in vitro assay, which allows the detection of estrogenic and cytotoxic compounds. This study, applying the YES assay, investigated the estrogenic activity and its potential risks to the aquatic biota of two streams in Santa Maria Madalena, Rio de Janeiro State, Southeastern Brazil. Estrogenic activity was observed only in São Domingos stream, with estradiol equivalent (EEQ) concentrations of 23 and 10.4 ng.L−1 during the dry and rainy season, respectively. The potential risks of this level of estrogenic activity were evaluated by a risk assessment, which revealed a high and medium risk to the local biota in the dry and rainy seasons, respectively. Among the studied water bodies, São Domingos watershed has a bigger population density and less sewage collection and treatment comparatively to Ribeirão Santíssimo stream. The YES assay presented itself as a useful tool for spotting estrogenic endocrine disruptors, with the potential to help in expanding knowledge about water bodies and to create and enforce environmental legislation and regulations.

Gasoline is a complex mixture of substances, including aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylenes (BTEX). These compounds are emitted into the air, with the special relevance of benzene since it is provenly carcinogenic. The study aimed to assess BTEX concentrations in filling stations in the city of Rio de Janeiro, Brazil, and to calculate the cancer risk associated with such exposures. Two types of sampling were performed (stationary and mobile), adapted from methodology n. 1,501 (U.S. National Institute for Occupational Safety and Health) for aromatic hydrocarbons, in six filling stations in the West Zone of Rio de Janeiro. Stationary sampling was done near the fuel pumps, while mobile sampling was done in the breathing zone of the workers (station attendants) as they moved around the station. The samples were analyzed with gas chromatography flame ionization detector. The sampling results were used to calculate the health risk, using the indicators Hazard quotient (HQ) and Cancer risk (CR) to assess the possible non-carcinogenic and carcinogenic effects, respectively, in filling station workers. Environmental concentrations for the most of the BTEX compounds were below the recommended limits, except for benzene, a carcinogenic compound, which displayed concentrations far above the limits, leading to high cancer risk values. The results showed that there are health risks for filling station attendants, especially the risk of developing cancer from excessive exposure to benzene.A gasolina é uma mistura complexa de substâncias, dentre elas estão hidrocarbonetos como o benzeno, tolueno, etilbenzeno e xilenos (BTEX), sendo esses compostos emitidos para a atmosfera, com destaque ao benzeno, por ser comprovadamente carcinogênico. Objetivamos avaliar as concentrações de BTEX no ar de postos de revenda de combustíveis no Município do Rio de Janeiro, Brasil, e calcular o risco de câncer associado a estas exposições. Foram realizados dois tipos de amostragem (fixa e móvel) adaptadas da metodologia nº 1.501 do Instituto Nacional de Segurança e Saúde Ocupacional (Estados Unidos), em seis postos de revenda de combustíveis na Zona Oeste da cidade. A amostragem fixa foi feita próxima às bombas de combustível, enquanto a móvel foi realizada através da coleta do ar na zona respiratória dos trabalhadores (frentistas), conforme estes se deslocavam pelo posto. As amostras foram analisadas por cromatografia gasosa com detecção por ionização em chama. Com os resultados das amostragens foram feitos os cálculos de risco à saúde, usando os indicadores Quociente de perigo (HQ) e Risco de câncer (CR), para avaliar os possíveis efeitos não-carcinogênicos e carcinogênicos, respectivamente, nos trabalhadores dos postos de revenda de combustíveis. As concentrações ambientais para a maioria dos compostos BTEX foram abaixo dos limites preconizados, menos para o benzeno, um composto carcinogênico, que apresentou concentrações muito acima dos limites, levando a altos valores de risco de câncer. Os resultados demonstraram que há riscos à saúde dos trabalhadores de postos de revenda de combustíveis, principalmente o risco de desenvolver câncer, devido à exposição excessiva ao benzeno.La gasolina es una mezcla compleja de sustancias, entre ellas existen hidrocarburos como el benceno, tolueno, etilbenceno y xilenos (BTEX), emitiéndose estos compuestos a la atmósfera, donde se destaca el benceno, al tratarse de un carcinogénico comprobado. Los objetivos fueron evaluar las concentraciones de BTEX en el aire de puestos de reventa de combustibles, en el municipio de Río de Janeiro, Brasil, así como calcular el riesgo de cáncer asociado a estas exposiciones. Se realizaron dos tipos de muestra (fija y movible), adaptadas de la metodología nº 1.501 del Instituto Nacional de Seguridad y Salud Laboral (EE.UU.), en seis puestos de reventa de combustibles de la zona oeste de la ciudad. La muestra fija se realizó cerca de las bombas de combustible, mientras que la móvil se hizo mediante tomas de aire en la zona respiratoria de los trabajadores (de la gasolinera), a medida que estos se desplazaban por el lugar de trabajo. Las muestras se analizaron por cromatografía gaseosa con detección por ionización en llama. Junto a los resultados de las muestras, se realizaron cálculos de riesgo para la salud, usando los indicadores Cociente de peligro (HQ) y Riesgo de cáncer (CR), con el fin de evaluar los posibles efectos no-carcinogénicos y carcinogénicos, respectivamente, en los trabajadores de los puestos de reventa de combustibles. Las concentraciones ambientales para la mayoría de los compuestos BTEX estuvieron por debajo de los limites preconizados, menos en el caso del benceno, un compuesto carcinogénico, que presentó concentraciones muy por encima de los límites, llevando a altos valores de riesgo de cáncer. Los resultados demostraron que existen riesgos para la salud de los trabajadores de puestos de reventa de combustibles, principalmente, riesgo de desarrollar cáncer, debido a la exposición excesiva al benceno.

Resumo Introdução Este estudo avaliou alterações respiratórias, auditivas e citogenéticas em trabalhadores de um estaleiro em Angra dos Reis, no Estado do Rio de Janeiro, relacionadas à exposição de pintores a solventes, metais e ruído no ambiente de trabalho. Métodos Foram avaliados função pulmonar, perdas auditivas e índice de reconhecimento da fala, e alterações citogenéticas pelo teste de aberrações cromossômicas. Foram avaliados manganês e chumbo em sangue por espectrometria de absorção atômica. Os indicadores de efeito utilizados para chumbo foram ALAD e ALA-U, determinados por espectrofotometria e cromatografia líquida, respectivamente. Resultados Seis dos 9 trabalhadores avaliados apresentaram alteração funcional respiratória. Quase 70% dos 18 trabalhadores avaliados apresentaram audição reduzida, com associação entre PAIR e chumbo em sangue. O percentual médio de recuperação da ALAD foi de 32,9%, com médias de ALA-U de 1,7 mg g-1 creatinina, 4,65 µg dL-1 para Pb-S e 10 µg L -1 para Mn-S entre os trabalhadores. Foram observadas associações entre ALA-D ativada com Mn-S e com a presença de aberrações cromossômicas. As alterações citogenéticas identificadas foram aneuploidias, separação prematura centromérica e aberrações como formação de anéis, quebras e união de cromátides irmãs. Conclusão os trabalhadores do estaleiro apresentam alterações que podem ser associadas à exposição ocupacional.

RESUMO A relação entre exposições ocupacionais, compostos químicos e doenças é conhecida há muito tempo e está no cerne do campo saúde-trabalho-ambiente. A pobreza presente na vida de numerosos trabalhadores brasileiros cria um cenário de vulnerabilidade social, gerando riscos à saúde. Este estudo tem por objetivo discutir a importância dos fatores socioeconômicos na avaliação da exposição ocupacional e a relação com o processo de saúde/doença dos trabalhadores, por meio de uma revisão exploratória da literatura. Diversos fatores estão ligados à forma como o trabalhador se relaciona com a exposição, como as condições de vida, moradia, acesso a serviços de saúde e educação, nível salarial e escolar. ABSTRACT The relationship between occupational exposures, chemical compounds and diseases has been known for a long time and is at the heart of the health-work-environment field. The condition of poverty in the lives of many Brazilian workers creates a scenario of social vulnerability, generating risks to health. This study aims to discuss the importance of socioeconomic factors in the evaluation of occupational exposure and the relationship with workers´ health/illness process, through an exploratory review of the literature. Several factors are related to how the worker relates to exposure, such as living conditions, housing, access to health and education services, salary levels and schooling.

Oxidative stress can be induced by mercury (Hg) exposure, including through fish consumption (diet), leading to health risks. The objective of this study was to evaluate the association between oxidative stress biomarkers and dietary Hg exposure levels in riverine children and adoluiaescents at Madeira River (RO/Brazil). Population from three riverine local communities presenting different fish consumption frequencies was sampled. Hg was determined in blood (ICP-MS) and glutathione (GSH), glutathione S-transferases (GST) and malondialdehyde (MDA) were determined in serum (spectrophotometry). Statistical analyses were performed using parametric and non-parametric tests. Multiple linear regression models and generalized additives models were also used to estimate the relationships between oxidative stress biomarkers and blood Hg. The juvenile riverine population from Cuni&atilde, RESEX presented the highest levels of oxidative stress and Hg levels in blood (GST = 27.2 (4.93) U/L, MDA = 1.69 (0.27) &micro, mol/L, Hg = 20.6 (18.0) &micro, g/L). This population also presented the highest frequency of fish consumption. The positive relation between Hg and GST and MDA, adjusted for individual characteristics, suggests an oxidative effect. This study shows the importance of oxidative stress biomarkers in the evaluation of dietary Hg exposure since initial and reversible metabolic changes were observed, enriching health risk assessments.

Environmental and occupational exposure to benzene from fuels is a major cause for concern for national and international authorities, as benzene is a known carcinogen in humans and there is no safe limit for exposure to carcinogens. The objective of this study was to evaluate the genotoxic effects of chronic occupational exposure to benzene among two groups of workers: filling station workers (Group I) and security guards working at vehicles entrances (Group II), both on the same busy highway in Rio de Janeiro, Brazil. Sociodemographic data on the workers were evaluated, the concentration of benzene/toluene (B/T) in atmospheric air and individual trans,trans-muconic acid (ttMA) and S-phenylmercapturic acid (S-PMA) were measured, oxidative stress was analyzed by catalase (CAT), glutathione S-transferase (GST), superoxide dismutase (SOD), thiol groups (THIOL) and malondialdehyde (MDA), genotoxicity was measured by metaphases with chromosomal abnormalities (MCA) and nuclear abnormalities, comet assay using the enzyme formamidopyrimidine DNA glycosylase (C-FPG), and methylation of repetitive element LINE-1, CDKN2B and KLF6 genes. Eighty-six workers participated: 51 from Group I and 35 from Group II. The B/T ratio was similar for both groups, but Group I had greater oscillation of benzene concentrations because of their work activities. No differences in ttMA and S-PMA, and no clinical changes were found between both groups, but linearity was observed between leukocyte count and ttMA, and 15% of workers had leukocyte counts less than 4.5 &times, 109 cells L&minus, 1, demanding close worker&rsquo, s attention. No differences were observed between the two groups for THIOL, MDA, MCA, or nuclear abnormalities. A multiple linear relationship was obtained for the biomarkers MCA and C-FPG. A significant correlation was found between length of time in current job and the biomarkers C-FPG, MCA, GST, and MDA. Although both populations had chronic exposure to benzene, the filling station workers were exposed to higher concentrations of benzene during their work activities, indicating an increased risk of DNA damage.

This study aimed to analyze teaching work's temporality aspects in their relationship with health. Qualitative research was conducted with the participation of ten professors from a public university. Six meetings called "Worker's Health workshops" were held, a research methodology that gathers workers and researchers to discuss topics related to work and health. The material was analyzed through the content analysis technique, in the thematic modality. The main themes were identified from the transcribed materials of the workshops' dialogues, namely: working time intensification and extension, teacher's health, working time and sleep deprivation, and health advocacy strategies and solutions. We noted that health advocacy strategies are located in individuals and the workgroup, through cooperation and social time. The theme of an intensive and extensive combination of working time associated with insecure work conditions was identified. We concluded that teaching work time is underpinned by rules and social values under the historical determination of new managerial standards within the public university.

Background Periodic assessment is one of the recommendations for improving health-care waste management worldwide. This study aimed at translating and adapting the Health-Care Waste Management - Rapid Assessment Tool (HCWM-RAT), proposed by the World Health Organization, to a Brazilian Portuguese version, and resolving its cultural and legal issues. The work focused on the evaluation of the concepts, items and semantic equivalence between the original tool and the Brazilian Portuguese version. Methods A cross-cultural adaptation methodology was used, including: initial translation to Brazilian Portuguese; back translation to English; syntheses of these translation versions; formation of an expert committee to achieve consensus about the preliminary version; and evaluation of the target audience’s comprehension. Results Both the translated and the original versions’ concepts, items and semantic equivalence are presented. The constructs in the original instrument were considered relevant and applicable to the Brazilian context. The Brazilian version of the tool has the potential to generate indicators, develop official database, feedback and subsidize political decisions at many geographical and organizational levels strengthening the Monitoring and evaluation (M&E) mechanism. Moreover, the cross-cultural translation expands the usefulness of the instrument to Portuguese-speaking countries in developing regions. Conclusion The translated and original versions presented concept, item and semantic equivalence and can be applied to Brazil

The aim of this work was to identify epistemological obstacles amongst participants of XXXIX Annual Meeting of Brazilian Society of Biochemistry and Molecular Biology. A questionnaire with selected excerpts of scientific papers from high impact factor journals was answered by 97 participants of this annual meeting (39 under-graduates, 42 graduate students, and 16 professors and researchers). From Bachelard’s notion of teleological obstacle, it was possible to identify vitalist conceptions (animism), teleological approaches of the evolution processes, expressed in apologies of immanent purposes in organisms’ adaptation, and an anthropomorphic vision of the biological processes under evaluation in the answers and also in the acceptance or not recognition of these obstacles in the excerpts. The presence of figures of speech, metaphors and analogies (verbal obstacle) were verified in explaining the evolution and the immune system, also present in the excerpts.

Among the epistemological obstacles described by Gaston Bachelard, we contend that unitary and pragmatic knowledge is correlated to the teleological categories of Ernst Mayr and is the basis for prevailing debate on the notion of "function" in biology. Given the proximity of the aspects highlighted by these authors, we propose to associate the role of teleological thinking in biology and the notion of unitary and pragmatic knowledge as an obstacle to scientific knowledge. Thus, teleological thinking persists acting as an epistemological obstacle in biology, according to Bachelardian terminology. Our investigation led us to formulate the "teleological obstacle," which we consider important for the future of biology and possibly other sciences.

Introduction Benzene is identified as a carcinogen. Long-term exposure to benzene causes haematological alterations, including an increased risk of acute myeloid leukaemia. However, the molecular mechanisms of Benzene systems effects remain poorly understood. Hence, a better understanding of the molecular mechanisms involved in this condition is a priority. Here, we employed a joint the integration of molecular networks, a gene–gene interaction database, biological processes analysis and functional annotation analysis to explore system effects for prioritising candidate genes to biomarkers to evaluate benzene exposure. Methods We selected 96 genes targets with altered expression in occupational exposed to benzene (2009 to 2014). The analysis was performed using the multiple association network integration algorithm for predicting gene function, which identifies known gene-gene interactions among a genes list and provides additional genes. Topological properties of network were calculated by MCODE, BINGO and Centiscape, Results A network of 114 genes and 2415 interactions were obtained. After topological analysis, a minor network composed by 16 nodes was identified, which is composed by most relevant nodes of major network. In this sub-network, KLF6, KLF4 and JUN are the most interconnected nodes, they being been considered a putative biomarker in which the exclusion of one node could produce a strong perturbation in the signalling network. Conclusion The biological interaction network method presented probabilities of interactions between genes, demonstrating the potential of the use and application of the multiple association network integration algorithms for predicting gene function and for the observation of multiple genes in the system, using theoretical data to building clusters for identification of possible genes as biomarker.

Este artigo tem como objetivo principal apresentar e analisar o instrumento de pesquisa designado como “cadernetas de saúde e trabalho”, com foco na produção de conhecimento sobre o trabalho de docentes de universidade pública. Trata-se de uma técnica de investigação de caráter qualitativo e participativo, adequada ao aprofundamento do estudo das relações entre a saúde e o trabalho, reavendo os locais de trabalho como lugares privilegiados de observações para o exercício de uma efetiva ação de defesa da saúde e a experiência do trabalho como matéria principal de análise. A qualidade especial das cadernetas como técnica de investigação refere-se ao papel protagonista atribuído ao trabalhador no processo de pesquisa, autor do diário e coparticipante do estudo. Participaram oito docentes pertencentes ao mesmo instituto de uma universidade federal de ensino superior (IFES), localizada no Rio de Janeiro, Brasil. Quanto à análise dos materiais empíricos, procedentes das anotações das cadernetas e de encontro com os trabalhadores, adotou-se a técnica de análise temática, chegando-se a quatro categorias principais de discussão, a saber: o tempo de trabalho e as múltiplas atividades de trabalho do professor; precarização das condições de trabalho em universidades; saúde docente entre limites e cadernetas sob o olhar dos seus autores. No que concerne aos resultados, sobressaiu o tema alusivo à sobrecarga de trabalho e pressão do tempo para cumprimento de metas. Ao fim, considerou-se que as cadernetas de saúde e trabalho mostraram-se como ferramenta de pesquisa com potencial para se gerar conhecimento em perspectiva coletiva. The main objective of this article is to present and analyze the research instrument called “health and work notebooks”, focusing on the production of knowledge concerning professors’ work at a public university. The notebooks serve as a qualitative and participant research technique that is appropriate for the in-depth study of relations between health and work, viewing workplaces as privileged spaces for exercising effective action in the defense of health and the work experience as the principal material for analysis. The notebooks’ special quality as a research technique lies in worker’s role as protagonist in the research, as the diary’s author and co-participant in the study. Eight professors participated, all from the same institute in a federal university (IFES) in Rio de Janeiro, Brazil. As for analysis of the empirical materials from the notebooks and consistent with the workers, the thematic analysis technique was adopted, producing four main discussion categories: time on the job and professors’ multiple work activities; precarization of working conditions at universities; faculty health at limits; and the notebooks viewed from the authors’ perspective. As for the results, the theme that stood out was work overload and time pressure to meet targets. Finally, the health and work notebooks proved to be a potential research tool for generating knowledge from a collective perspective. El objetivo principal de este artículo es presentar y analizar el instrumento de investigación denominado “cartillas de salud y trabajo”, centrándose en la producción de conocimiento sobre el trabajo de docentes de universidad pública. Se trata de una técnica de investigación de carácter cualitativo y participativo, adecuada a la profundización del estudio de las relaciones entre la salud y el trabajo, reincorporando los lugares de trabajo como lugares privilegiados de observación para el ejercicio de una efectiva acción de defensa de la salud, y la experiencia laboral como materia principal de análisis. La cualidad especial de las cartillas como técnica de investigación se refiere al papel protagonista, atribuido al trabajador en el proceso de investigación, autor del diario y coparticipante del estudio. Participaron ocho docentes pertenecientes al mismo instituto de una universidad federal de enseñanza superior (IFES), localizada en Río de Janeiro, Brasil. En cuanto al análisis de los materiales empíricos, procedentes de las anotaciones de las cartillas y de encuentros con los trabajadores, se adoptó la técnica de análisis temático, llegándose a cuatro categorías principales de discusión, a saber: el tiempo de trabajo y las múltiples actividades de trabajo del profesor; precarización de las condiciones de trabajo en universidades; salud docente entre límites y cartillas bajo la atenta mirada de sus autores. En lo que concierne a los resultados, se resaltó el tema alusivo a la sobrecarga de trabajo y presión de tiempo para el cumplimiento de metas. Al final, se consideró que las cartillas de salud y trabajo se mostraron como herramientas de investigación con potencial para generar conocimiento desde una perspectiva colectiva.

(RBSO) apresenta o Dossie Tematico “Exposicao ocupacional ao benzeno na cadeia de distribuicao e revenda de combustiveis no Brasil”, que traz para o debate producao elaborada a partir do aprendizado coletivo e da experiencia de grupo de pesquisadores, tecnicos e gestores do Sistema Unico de Saude (SUS), e de autores convidados, que atuam nas questoes relacionadas com a exposicao ao benzeno no trabalho, sobretudo por meio das acoes dos Centros de Referencia em Saude do Trabalhador (Cerest). Essa producao e, portanto, resultado de estudos, da analise de registros historicos e normativos, e das praticas dos servicos publicos de saude. Com essa conformacao e diferentes perspectivas, sao apresentadas contribuicoes de/para a pesquisa, abordando questoes de organizacao dos trabalhadores e de seus ambientes de trabalho, das acoes de vigilância do SUS (por meio da divulgacao dos resultados de estudos de diferentes regioes do pais), do fazer dos servicos especializados em Saude do Trabalhador, que, junto com os registros da experiencia de exposicao dos trabalhadores do ramo, com-poem as licoes no campo da exposicao ocupacional ao benzeno no Brasil.O foco central deste dossie foi agregar novos conhecimentos, que inte-gram saberes interdisciplinares sobre os riscos, o monitoramento e as consequencias da exposicao ocupacional ao benzeno, com o objetivo de qualificar a investigacao em ambientes de trabalho dos postos de revenda de combustiveis (PRC) e, com isso, subsidiar medidas e programas de pro -tecao a saude dos trabalhadores. A importância desta publicacao deve-se a complexidade e gravidade dessa exposicao e aos seus efeitos nocivos a saude, bem como as lacunas que ainda persistem no campo da pesquisa e do registro da historia brasileira sobre o assunto.No Brasil, estudo de Costa e Goldbaum

Resumo Introdução: trabalhadores de postos de combustíveis estão expostos às diversas substâncias químicas presentes no ambiente de trabalho, destacando-se entre elas o benzeno, devido às suas propriedades carcinogênicas. Objetivo: avaliar os danos genotóxicos relacionados à exposição ocupacional ao BTEX (benzeno, tolueno, etilbenzeno, xilenos) em trabalhadores de cinco postos de combustíveis do município do Rio de Janeiro, RJ. Metodologia: foram analisadas concentrações de BTEX no ar; atividades das enzimas catalase e glutationa S-transferase; e ensaio cometa em amostras de sangue total de 97 trabalhadores. Resultados: as concentrações de BTEX estavam dentro dos valores preconizados pela NR 15, incluindo Anexo 13-A. Entretanto, uma oscilação nos resultados de ensaio cometa foi observada entre os trabalhadores dos diferentes postos de combustíveis, principalmente em trabalhadores de postos com menores concentrações de benzeno. Discussão: esse resultado está de acordo com a literatura científica atual, que indica uma curva dose-resposta supralinear para o benzeno, observando-se em baixas concentrações um aumento não linear do risco de leucemia, provavelmente relacionado à maior metabolização do benzeno e à maior produção de seus metabólitos tóxicos nessas concentrações. Conclusão: os resultados deste estudo sugerem que a exposição ao BTEX, mesmo em baixas concentrações, contribui para o risco genotóxico à saúde humana.

Outra Agência Introdução: a avaliação de uma exposição mensura sua intensidade, frequência e duração, podendo detectar danos precoces que, se ignorados, podem evoluir para um quadro nocivo. Nos campos da saúde ambiental e ocupacional, os biomarcadores de genotoxicidade tem sido largamente utilizados para essa avaliação. Objetivo: identificar, descrever e discutir os principais bioindicadores de genotoxicidade e seu uso conjunto com técnicas de avaliação de expressão gênica em estudos de exposição ocupacional ao benzeno em postos de revenda de combustíveis (PRC). Métodos: revisão bibliográfica de trabalhos publicados entre 1995 e 2015. Resultados: as técnicas identificadas foram: ensaio cometa, estresse oxidativo, micronúcleos, aberrações cromossômicas, polimorfismos, adutos de DNA e proteínas, fatores epigenéticos e expressão gênica. Foi observado que testes de danos genéticos e epigenéticos são utilizados em frentistas de PRC que participam de programas de saúde do trabalhador ou de pesquisas, embora um baixo número de publicações sobre o tema tenha sido identificado. Esse fato talvez possa ser explicado pelos poucos países onde a profissão persiste e pelas limitações para o desenvolvimento de pesquisas nesses países. Conclusão: os bioindicadores de genotoxicidade e as técnicas de expressão gênica são úteis na detecção de dano precoce desta exposição ocupacional e devem ser avaliados em conjunto. Introduction: an exposure evaluation measures its intensity, frequencyand duration, detecting premature damage that, if ignored, might develop into a harmful framework. On environmental and occupational health fields, genotoxicity biomarkers have been widely used for this evaluation. Objective: to identify, describe and discuss main genotoxicity biomarkers and their use together with gene expression evaluation techniques in studies concerning occupational exposure to benzene in gas stations (GS). Methods: bibliographical review of studies published between 1995 and 2015. Results: the following techniques were identified: comet assay, oxidative stress, micronuclei, chromosomal aberrations, polymorphisms, DNA and protein adducts, epigenetic factors and gene expression. We observed that genetic and epigenetic damage tests are used in gas station attendants who participate in worker’s health programs or in researches, although a short number of publications on the theme have been identified. This can be explained by the small number of countries where such job still exists and by the limitations for developing research in such countries. Conclusion: genotoxicity biomarkers and gene expression techniques are useful for detecting the premature damage resulting from this occupational exposure and must be jointly evaluated.

The main objective of this article is to present and analyze the research instrument called "health and work notebooks", focusing on the production of knowledge concerning professors' work at a public university. The notebooks serve as a qualitative and participant research technique that is appropriate for the in-depth study of relations between health and work, viewing workplaces as privileged spaces for exercising effective action in the defense of health and the work experience as the principal material for analysis. The notebooks' special quality as a research technique lies in worker's role as protagonist in the research, as the diary's author and co-participant in the study. Eight professors participated, all from the same institute in a federal university (IFES) in Rio de Janeiro, Brazil. As for analysis of the empirical materials from the notebooks and consistent with the workers, the thematic analysis technique was adopted, producing four main discussion categories: time on the job and professors' multiple work activities; precarization of working conditions at universities; faculty health at limits; and the notebooks viewed from the authors' perspective. As for the results, the theme that stood out was work overload and time pressure to meet targets. Finally, the health and work notebooks proved to be a potential research tool for generating knowledge from a collective perspective.Este artigo tem como objetivo principal apresentar e analisar o instrumento de pesquisa designado como “cadernetas de saúde e trabalho”, com foco na produção de conhecimento sobre o trabalho de docentes de universidade pública. Trata-se de uma técnica de investigação de caráter qualitativo e participativo, adequada ao aprofundamento do estudo das relações entre a saúde e o trabalho, reavendo os locais de trabalho como lugares privilegiados de observações para o exercício de uma efetiva ação de defesa da saúde e a experiência do trabalho como matéria principal de análise. A qualidade especial das cadernetas como técnica de investigação refere-se ao papel protagonista atribuído ao trabalhador no processo de pesquisa, autor do diário e coparticipante do estudo. Participaram oito docentes pertencentes ao mesmo instituto de uma universidade federal de ensino superior (IFES), localizada no Rio de Janeiro, Brasil. Quanto à análise dos materiais empíricos, procedentes das anotações das cadernetas e de encontro com os trabalhadores, adotou-se a técnica de análise temática, chegando-se a quatro categorias principais de discussão, a saber: o tempo de trabalho e as múltiplas atividades de trabalho do professor; precarização das condições de trabalho em universidades; saúde docente entre limites e cadernetas sob o olhar dos seus autores. No que concerne aos resultados, sobressaiu o tema alusivo à sobrecarga de trabalho e pressão do tempo para cumprimento de metas. Ao fim, considerou-se que as cadernetas de saúde e trabalho mostraram-se como ferramenta de pesquisa com potencial para se gerar conhecimento em perspectiva coletiva.El objetivo principal de este artículo es presentar y analizar el instrumento de investigación denominado “cartillas de salud y trabajo”, centrándose en la producción de conocimiento sobre el trabajo de docentes de universidad pública. Se trata de una técnica de investigación de carácter cualitativo y participativo, adecuada a la profundización del estudio de las relaciones entre la salud y el trabajo, reincorporando los lugares de trabajo como lugares privilegiados de observación para el ejercicio de una efectiva acción de defensa de la salud, y la experiencia laboral como materia principal de análisis. La cualidad especial de las cartillas como técnica de investigación se refiere al papel protagonista, atribuido al trabajador en el proceso de investigación, autor del diario y coparticipante del estudio. Participaron ocho docentes pertenecientes al mismo instituto de una universidad federal de enseñanza superior (IFES), localizada en Río de Janeiro, Brasil. En cuanto al análisis de los materiales empíricos, procedentes de las anotaciones de las cartillas y de encuentros con los trabajadores, se adoptó la técnica de análisis temático, llegándose a cuatro categorías principales de discusión, a saber: el tiempo de trabajo y las múltiples actividades de trabajo del profesor; precarización de las condiciones de trabajo en universidades; salud docente entre límites y cartillas bajo la atenta mirada de sus autores. En lo que concierne a los resultados, se resaltó el tema alusivo a la sobrecarga de trabajo y presión de tiempo para el cumplimiento de metas. Al final, se consideró que las cartillas de salud y trabajo se mostraron como herramientas de investigación con potencial para generar conocimiento desde una perspectiva colectiva.

Resumo Introdução: trabalhadores estão sujeitos a riscos decorrentes da exposição ambiental e ocupacional ao benzeno, situação ainda mais crítica quando associada a fatores como desigualdade social, múltipla exposição, suscetibilidade individual, degradação ambiental e às possíveis interações entre os contaminantes ambientais. Além disso, nem sempre as regulamentações são estabelecidas e/ou atualizadas apenas a partir de achados científicos, pois são processos permeados por conflitos de interesses. Objetivo: realizar análise crítica sobre a identificação de risco e avaliação da exposição ao benzeno. Métodos: revisão bibliográfica e documental do marco normativo brasileiro e internacional sobre exposição ao benzeno, com relação aos aspectos toxicológicos, de exposição ocupacional e ambiental e de avaliação de risco. Discussão: o controle da exposição ao benzeno permeia o campo da disputa técnico-política de saúde e segurança, constituindo-se em marco regulatório resultante de consenso de entendimentos. Esses entendimentos são marcados pela disputa entre a proteção à saúde e a gestão empresarial das condições de trabalho, em detrimento das evidencias científicas. Em tal contexto, os Limites de Exposição Ocupacional podem variar significativamente entre os países e agências, apesar do reconhecimento universal de que não há limites seguros para exposição ao benzeno, por ser um composto carcinogênico. Abstract Introduction: workers are subject to risks from environmental and occupational exposure to benzene. This situation is even more critical when combined with social inequality, multiple exposure, individual susceptibility, environmental degradation, and possible interactions between environmental contaminants. In addition, regulations are not always established and/or updated only from scientific evidences, because they are processes permeated by conflicts of interest. Objective: to produce a critical analysis on risk identification and benzene exposure evaluation. Methods: literature and documentary review of the Brazilian and international regulatory standards on benzene exposure, toxicological aspects, occupational and environmental exposure, and risk evaluation. Discussion: benzene exposure control permeates the technical-political dispute of health and safety, resulting in a regulatory standard from consensus of understandings. These understandings are shaped by the dispute between health protection and business management of working conditions, to the detriment of scientific evidence. In this context, the Occupational Exposure Limits can vary significantly between countries and agencies, despite the universal recognition that there are no safe limits for benzene exposure, because it is a carcinogenic compound.

Resumo Introdução: trabalhadores de postos de revenda de combustíveis estão expostos a compostos orgânicos voláteis, dos quais se destaca o benzeno. O manejo clínico do amplo espectro de sinais e sintomas desses trabalhadores ainda é um desafio para assistência em saúde. Objetivo: apresentar proposta de classificação clínico-laboratorial baseada na análise de hemograma e na avaliação clínica dos trabalhadores, para orientar a conduta dos profissionais de saúde. Métodos: a classificação clínico-laboratorial foi definida a partir de critérios de hierarquização dos resultados das avaliações clínicas e de vigilância à saúde de modo a possibilitar a organização dos procedimentos e fluxos de atenção à saúde. Resultados: a proposta define o manejo clínico com base na classificação dos expostos ao benzeno em quatro níveis de alterações clínico-laboratoriais que determinam os procedimentos compatíveis com o grau da exposição e de seus efeitos à saúde: 1) sem alterações significativas; 2) alterações inespecíficas ou incompletas, 3) alterações clínicas e/ou laboratoriais; 4) alterações sugestivas de benzenismo. Conclusão: a proposta de classificação dos achados clínico-laboratoriais é potencialmente capaz de orientar a conduta médica na avaliação das condições de saúde e dos riscos da exposição ao benzeno e de subsidiar o monitoramento sistemático e contínuo necessário para a definição de rotinas assistenciais para os coletivos de trabalhadores. Abstract Introduction: gas stations workers are exposed to volatile organic compounds, especially benzene. Clinical management of the broad spectrum of symptoms and signs observed in these workers is still a challenge for health care. Objective: to present a clinical-laboratory classification, based on hemogram analysis and clinical evaluation of workers exposed to benzene, as guidelines for health care professionals. Methods: the clinical-laboratory classification was defined based on priority-setting criteria for the results of clinical evaluations and health surveillance in order to allow the organization of health care flows and procedures. Results: the proposal defines the clinical management based on classification of workers exposed to benzene in four levels of clinical and laboratory alterations that determine procedures according to level of exposure and health effects: 1) without significant alterations; 2) unspecific or incomplete alterations; 3) clinical and/or laboratory alterations; and 4) alterations suggesting benzene poisoning. Conclusion: the proposal for classification of clinical and laboratory findings is potentially able to guide medical practice in the assessment of health conditions and risks of benzene exposure, and subsidize the systematic and continuous monitoring necessary for establishing health care practices offered to workers.

Despite Brazil’s large numbers and its position as one of the world’s ten largest economies, its exports are mainly composed of non-industrial or low-technological goods. It results in a trade deficit and technological dependence that affects several sectors, including biotechnology. The present study aims at analyzing the Brazilian trade balance (from 1996 to 2013) of enzyme-related goods and correlating such data with the scientific community, number of scientific publications and filings of patent applications related to four technological areas that commonly use lipases, the most important enzyme studied in Brazil. Brazil seems to have a sufficient, but not saturated, technical staff working in enzyme-correlated areas, while the trade balance is deteriorating over the years. The major problem seems to be that the increase in the number of scientists is not accompanied by a proportional increase in effective development policies. These conclusions are corroborated by the number of scientific publications and patent documents related to the industrial use of lipases, one of the most important enzyme group: while Brazil has an important contribution in publishing scientific documents regarding the industrial use of lipases, its contribution in filing patent applications is only marginal.

Genotoxic effects of occupational workers exposed to asbestos can be evaluated using different biomarkers as oxidative stress enzymes in conjuction with comet assay. This study assessed changes to oxidative stress enzymatic parameters and genotoxic damage in workers occupationally exposed and non-exposed to chrysotile asbestos, who attended the outpatient Clinic of the Center for Worker Health Studies and Human Ecology (CESTEH/ENSP/FIOCRUZ) in Brazil. Chest radiography and spirometry were performed to assess clinical progression of symptoms. The traditional visual score comet assay in peripheral whole blood cells was used to assess DNA damage, and oxidative stress was evaluated by measuring catalase (CAT) and glutathione S-transferase (GST) activities. Respiratory alterations were observed in 53% of workers exposed, as determined by pulmonary function and bronchodilation, and 6 workers were diagnosed with asbestosis. The comet assay was statistically significantly higher in the exposed group and individuals with asbestosis compared to the non-exposed group and individuals without asbestosis, respectively. Linear regression analysis showed that 28,4% and 50,5% of comet assay results were increased by exposure to asbestos and developed asbestosis. The results of CAT and GST were not difference between the groups. These results supports the association of genotoxic damage and the onset of asbestosis by chrysotile asbestos exposure in workers of this study.

O estrogênio sintético 17α-etinilestradiol, principal componente utilizado em formulações de contraceptivos orais, tem sido apontado como um dos principais compostos responsáveis por provocar efeitos adversos no sistema endócrino de várias espécies. O objetivo deste estudo foi analisar o estado da arte dos dispositivos legais e normativos referentes ao controle desse estrogênio sintético nas águas da Europa e dos Estados Unidos, e traçar um paralelo com a realidade brasileira. No geral, os países têm buscado ampliar a regulamentação e monitoramento de alguns micropoluentes emergentes que antes não eram objeto de atenção por parte dos dispositivos legais. A Europa está mais avançada no que tange à qualidade dos corpos hídricos, enquanto que nos Estados Unidos esta substância é alvo de regulamentação apenas para a água destinada ao consumo humano. No Brasil, ainda não há nenhum dispositivo legal ou normativo que aborde esse estrogênio, o que pode ser associado a uma baixa maturidade do sistema brasileiro quanto ao controle de poluentes hídricos.

L-asparaginase is an enzyme used as a chemotherapeutic agent, mainly for treating acute lymphoblastic leukemia. In this study, the gene of L-asparaginase from Zymomonas mobilis was cloned in pET vectors, fused to a histidine tag, and had its codons optimized. The L-asparaginase was expressed extracellularly and intracellularly (cytoplasmically) in Escherichia coli in far larger quantities than obtained from the microorganism of origin, and sufficient for initial cytotoxicity tests on leukemic cells. The in silico analysis of the protein from Z. mobilis indicated the presence of a signal peptide in the sequence, as well as high identity to other sequences of L-asparaginases with antileukemic activity. The protein was expressed in a bioreactor with a complex culture medium, yielding 0.13 IU/mL extracellular L-asparaginase and 3.6 IU/mL intracellular L-asparaginase after 4 h of induction with IPTG. The cytotoxicity results suggest that recombinant L-asparaginase from Z. mobilis expressed extracellularly in E.coli has a cytotoxic and cytostatic effect on leukemic cells.

The proportion of nitrogenated compounds such as carbazole in heavy fractions of crude oil is higher in Brazil than in other parts of the world. The degradation of this compound by microorganisms has already been described for bacteria such as Pseudomonas stutzeri ATCC 31258. Assays were undertaken to assess the influence of different carbazole concentrations on cell growth, carbazole degradation and the formation of anthranilic acid (an intermediate in the carbazole degradation pathway). The results indicated that there was an accumulation of anthranilic acid in the medium with the higher concentration of substrate (10 g/L), which could be related to the inhibition of Pseudomonas stutzeri growth in an excess of carbazole. With 1 g/L of carbazole, growth was found to be ten times greater (0.37 g dry cell weight/L) and there was no accumulation of anthranilic acid (formation of around 7 mg/L), with complete carbazole degradation after three days.

The synthetic estrogen 17α-ethinylestradiol, the principal component of oral contraceptives, has been identified as one of the main compounds accounting for adverse effects on the endocrine system in various species. This study aimed to analyze the state-of-the-art in legislation and guidelines for the control of this synthetic estrogen in water bodies in Europe and the United States and to draw a parallel with the Brazilian reality. Countries have generally attempted to expand the regulation and monitoring of certain emerging micropollutants not previously covered by legislation. Europe is more advanced in terms of water quality, while in the United States this estrogen is only regulated in water for human consumption. Brazil still lacks legal provisions or standards for this estrogen, which can be explained by the relatively limited maturity of the country's system for controlling water pollutants.

This work aimed to adapt the analysis of methemoglobin recommended by Evelyn - Malloy (visible spectrophotometry), in order to facilitate its application in the field, or to analysis in clinical laboratory, of existing sites of diflubenzuron application. The parameters changed included: centrifuge rotation speed; time between the collection of biological sample and analysis, and storage temperature of the samples; and the volume of reagents. The comparison of the rotation speed (rpm) of the reference methodology with the rpm of a "clinical centrifuge" did not reveal a statistically significant difference in the levels of methemoglobin. The time between the collection of biological sample and analysis was extended for a period of up to 48 hours for both conservation by refrigeration and ambient temperature, producing no statistically significant difference when compared to the standard duration of 2 hours. Regarding the reagents, the reference methodology already uses the volume necessary to ensure complete reaction, whereas a wider range from the recommended volume to a 5-fold reduction in comparison to the reference methodology could be used. It was concluded that the proposed changes to the methodology for adapting the analysis are applicable to studies of field / workplace exposure and ensure the reliability of results. The adapted methodology was inter-laboratory validated and the parameters changed can be selected according to the requirements of the laboratory at which the methemoglobin is to be measured.

In this report the ORF PF2001 from the hyperthermophilic archaeon Pyrococcus furiosus was identified and its protein sequence was characterized in silico, revealing characteristics of the conserved domains of the dipeptidyl aminopeptidases, hydrolases of the α/β superfamily, esterases and lipases. In order to understand its function, the ORF PF2001 without the 60 bp of the 5′-terminus, responsible for encoding a signal peptide ( PF2001Δ60 ), was cloned and expressed in Escherichia coli BL21(DE3) pLysS, and the recombinant enzyme was characterized for esterase, lipase and protease activities. The total protein extract from E. coli harboring the plasmid containing the ORF PF2001Δ60 exhibited its highest activity towards the substrate 4-methylumbelliferyl-heptanoate (C7) and lower activities towards 4-methylumbelliferyl-acetate (C2) and 4-methylumbelliferyl-palmitate (C16). The enzyme was thermostable for 120 min at 75 °C and was completely inhibited by 1 mM PMSF. A theoretical structural model was constructed by comparative modeling using as template a prolyl oligopeptidase from Sus scrofa . Although no protease activity was detected a putative catalytic triad (Ser149, Asp233 and His264) with high similarity to the template was identified. The structural characteristics that confer enzymatic specificity to the P. furiosus enzyme are discussed. Taken together the data strongly suggest that ORF PF2001 from P. furiosus is responsible for encoding a novel esterase.

In this work, the 1082bp PCR product corresponding to carBaBb genes that encode the heterotetrameric enzyme 2'-aminobiphenyl-2,3-diol 1,2-dioxygenase (CarB), involved in the Pseudomonas stutzeri ATCC 31258 carbazole degradation pathway, was cloned using the site-specific recombination system. Recombinant clones were confirmed by PCR, restriction enzyme digestion and sequencing. CarB dioxygenase was expressed in high levels and in active form in Escherichia coli BL21-SI using the His-tagged expression vector pDEST TM17 and salt induction for 4h.Carbazol e seus derivados são compostos nitrogenados aromáticos, presentes comumente em petróleo e potencialmente poluentes. A rota de biodegradação de carbazol a ácido antranílico em Pseudomonas sp. é composta por três enzimas responsáveis, respectivamente, pelas reações de dioxigenação angular, meta-clivagem e hidrólise. A segunda enzima da rota, 2'-aminobifenil-2,3-diol 1,2-dioxigenase (CarB), codificada por dois genes (carBa e carBb), é um heterotetrâmero com atividade catalítica na quebra do anel catecol do susbtrato na posição meta. Neste trabalho, foi clonado o produto de PCR de 1082pb correspondente aos genes carBaBb da bactéria degradadora de carbazol Pseudomonas stutzeri ATCC 31258. A estratégia de clonagem empregada foi a de recombinação sítio-específica e a construção dos plasmídeos foi confirmada por PCR, digestão com enzima de restrição e seqüenciamento. A enzima ativa foi expressa em altas concentrações em vetor pDEST TM17 com cauda de histidina e promotor T7 em Escherichia coli BL21-SI com indução por NaCl durante 4h.

The proper determination of experimental errors in catalytic processes may be very important because experimental errors can exert a major impact upon the analysis of experimental results. For this reason, the influence of temperature upon the experimental errors observed during the combined carbon dioxide reforming and partial oxidation of methane over Pt/-Al2O3 is studied here. It is shown that fluctuations of output stream compositions may decrease more than one order of magnitude as reactor temperature increases in the range from 600 to 1100 ◦ C during catalytic tests. Additionally, it is shown that the covariance matrix of composition measurements is not diagonal, as usually assumed, and may change very significantly with the experimental conditions. Therefore, experimental errors should not be regarded as constant and covariance matrices should not be assumed to be diagonal a priori for kinetic model building and parameter estimation. It is also shown that the covariance matrix may contain significant amount of information about the reaction mechanism, which can be used for model building and interpretation of kinetic experiments. Particularly, it is shown that the actual experimental error may be much smaller than usually obtained when covariance terms are neglected and that fluctuation of catalyst activity may concentrate most of the experimental fluctuations observed experimentally. © 2002 Elsevier Science B.V. All rights reserved.

Background Leptospirosis is a zoonose that is increasingly endemic in built-up areas, especially where there are communities living in precarious housing with poor or non-existent sanitation infrastructure. Leptospirosis can kill, for its symptoms are easily confused with those of other diseases. As such, a rapid diagnosis is required so it can be treated effectively. A test for leptospirosis diagnosis using Leptospira Immunoglobulin-like (Lig) proteins is currently at final validation at Fiocruz. Results In this work, the process for expression of LigB (131-645aa) in E. coli BL21 (DE3)Star™/pAE was evaluated. No significant difference was found for the experiments at two different pre-induction temperatures (28°C and 37°C). Then, the strain was cultivated at 37°C until IPTG addition, followed by induction at 28°C, thereby reducing the overall process time. Under this condition, expression was assessed using central composite design for two variables: cell growth at which LigB (131-645aa) was induced (absorbance at 600 nm between 0.75 and 2.0) and inducer concentration (0.1 mM to 1 mM IPTG). Both variables influenced cell growth and protein expression. Induction at the final exponential growth phase in shaking flasks with Absind = 2.0 yielded higher cell concentrations and LigB (131-645aa) productivities. IPTG concentration had a negative effect and could be ten-fold lower than the concentration commonly used in molecular biology (1 mM), while keeping expression at similar levels and inducing less damage to cell growth. The expression of LigB (131-645aa) was associated with cell growth. The induction at the end of the exponential phase using 0.1 mM IPTG at 28°C for 4 h was also performed in microbioreactors, reaching higher cell densities and 970 mg/L protein. LigB (131-645aa) was purified by nickel affinity chromatography with 91% homogeneity. Conclusions It was possible to assess the effects and interactions of the induction variables on the expression of soluble LigB (131-645aa) using experimental design, with a view to improving process productivity and reducing the production costs of a rapid test for leptospirosis diagnosis.

The study of the stability of concentrated oil-in-water emulsions is imperative to provide a scientific approach for an important problem in the beverage industry, contributing to abolish the empiricism still present nowadays. The use of these emulsions would directly imply a reduction of transportation costs between production and the sales points, where dilution takes place. The goal of this research was to evaluate the influence of the main components of a lemon emulsion on its stability, aiming to maximize the concentration of oil in the beverage and to correlate its physicochemical characteristics to product stability, allowing an increase of shelf life of the final product. For this purpose, analyses of surface and interface tension, electrokinetic potential, particle size and rheological properties of the emulsions were conducted. A 2(4-1) fractional factorial design was performed with the following variables: lemon oil/water ratio (30% to 50%), starch and Arabic gum concentrations (0% to 30%) and dioctyl sodium sulfosuccinate (0 mg/L to 100 mg/L), including an evaluation of the responses at the central conditions of each variable. Sequentially, a full design was prepared to evaluate the two most influential variables obtained in the first plan, in which concentration of starch and gum ranged from 0% to 20%, while concentration of lemon oil/water ratio was fixed at 50%, without dioctyl sodium sulfosuccinate. Concentrated emulsions with stability superior to 15 days were obtained with either starch or Arabic gum and 50% lemon oil. The most stable formulations presented viscosity over 100 cP and ratio between the surface tension of the emulsion and the mucilage of over 1. These two answers were selected, since they better represent the behavior of emulsions in terms of stability and could be used as tools for an initial selection of the most promising formulations.

Atualmente, a substância utilizada para o combate do vetor da dengue é o diflubenzuron, um larvicida que possui como principal efeito no ser humano a formação demetemoglobina. A determinação do percentual de metemoglobina (MHb) no sangue permite estabelecer a relação com a exposição ao diflubenzuron, sendo utilizada como indicador de efeito. O objetivo do presente trabalho foi avaliar a efetividade do uso da MHb como indicador da exposição ao diflubenzuron por meio da determinação de sua concentração no sangue de guardas de endemias atuantes em dois municípios do Estado do Rio de Janeiro. Para a avaliação da MHb, foi utilizado o método de análise preconizado por Evelyn-Malloy, a espectrofotometria no visível λmáx=630 nm, e as informações complementares foram obtidas por intermédio da aplicação de questionários semiestruturados. Foi observado que a maioria dos trabalhadores não fazia uso de Equipamento de Proteção Individual (EPI) e atuava em condições de trabalho insalubres e sem treinamento adequado. Houve redução de cerca de 0,05% da concentração da MHb após a exposição ao diflubenzuron, com correlação inversa deste indicador de efeito com a variável fumo (R= -0,742; p=0,035). Dado que a MHb pode ser formada após exposição a diversas substâncias químicas e considerando as dificuldades na logística de execução desta análise, estudos sobre novos biomarcadores mais sensíveis e seletivos são necessários. Currently, the substance used to combat the dengue vector is diflubenzuron, a larvicide which produces methemoglobin (MHb) in humans. During his working process, applicators may be exposed to this substance at different levels, which depend on the care they adopt in handling and application. Knowing the profile of workers is important to characterize the population and assess the risks they face. The determination of the percentage of MHb in the blood allows to establish a relationship with exposure to diflubenzuron, being used as an indicator of effect. The objective of this study was to evaluate the extent to which these factors can affect the exposure of active endemic guards in two municipalities of the State of Rio de Janeiro contributed to a better understanding of the issues arising from this work process. It was observed that most workers did not use Personal Protective Equipment (PPE) and worked in unsafe working conditions and without proper training. Was observed a large difference in knowledge of the risks arising from the work they perform in the two counties, showing weaknesses in the basic training of these professionals. There was a reduction of about 0.05% of the MHb concentration after exposure to diflubenzuron, with an inverse correlation between this indicator variable effect with smoking (R= -0.742; p=0.035). Since MHb can be formed after exposure to various chemicals and considering the logistical difficulties in implementing this analysis, studies on new more sensitive and selective biomarkers are needed.

Background Streptococcus pneumoniae (S. pneumoniae) causes several serious diseases including pneumonia, septicemia and meningitis. The World Health Organization estimates that streptococcal pneumonia is the cause of approximately 1.9 million deaths of children under five years of age each year. The large number of serotypes underlying the disease spectrum, which would be reflected in the high production cost of a commercial vaccine effective to protect against all of them and the higher level of amino acid sequence conservation as compared to polysaccharide structure, has prompted us to attempt to use conserved proteins for the development of a simpler vaccine. One of the most prominent proteins is pneumolysin (Ply), present in almost all the serotypes known at the moment, which shows an effective protection against S. pneumoniae infections. Results We have cloned the pneumolysin gene from S. pneumoniae serotype 14 and studied the effects of eight variables related to medium composition and induction conditions on the soluble expression of rPly in Escherichia coli (E. coli) and a 28-4 factorial design was applied. Statistical analysis was carried out to compare the conditions used to evaluate the expression of soluble pneumolysin; rPly activity was evaluated by hemolytic activity assay and served as the main response to evaluate the proper protein expression and folding. The optimized conditions, validated by the use of triplicates, include growth until an absorbance of 0.8 (measured at 600 nm) with 0.1 mM IPTG during 4 h at 25°C in a 5 g/L yeast extract, 5 g/L tryptone, 10 g/L NaCl, 1 g/L glucose medium, with addition of 30 μg/mL kanamycin. Conclusions This experimental design methodology allowed the development of an adequate process condition to attain high levels (250 mg/L) of soluble expression of functional rPly in E. coli, which should contribute to reduce operational costs. It was possible to recover the protein in its active form with 75% homogeneity.