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Avaliação genotóxica e mutagênica de anti-hipertensivos distribuídos pela farmácia popular em células do sistema imunológico humanoLeão, Maria Fernanda de Moura January 2016 (has links)
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Previous issue date: 2016 / A hipertensão arterial é uma condição clínica de ocorrência multifatorial, sendo a mais frequente entre as doenças crônicas não transmissíveis no Brasil. É caracterizada pelo aumento e manutenção dos níveis pressóricos acima de 140mmHg (pressão sistólica) e 90mmHg (pressão diastólica). É também o maior agravante nas complicações cardiovasculares e está associada ao surgimento de outras co-morbidades. A OMS estima que 40% da população mundial acima dos 25 anos seja hipertensa, estando localizada majoritariamente em países onde a renda e o nível de escolaridade são menores. Depois de diagnosticada, a hipertensão arterial deve ser tratada com mudanças no estilo de vida e medicamentos que mantenham os níveis pressóricos controlados, sendo assim, várias classes de anti-hipertensivos são usados nesse tratamento. Visando ampliar o acesso a medicamentos básicos e permitir uma melhor adesão ao tratamento, o Governo Federal criou em 2004 o Programa Farmácia Popular do Brasil, uma parceria entre governo e instituições públicas e privadas para fornecer a população medicamentos para o controle da hipertensão, diabetes, asma, dislipidemias, anticoncepcionais, entre outros; de forma gratuita ou subsidiada em até 90% do valor. Para tratar a hipertensão, o Programa Farmácia Popular do Brasil distribui de forma gratuita os anti-hipertensivos – atenolol, captopril, cloridrato de propranolol, hidroclorotiazida, losartana e maleato de enalapril, todos estes sendo lançados no mercado anterior ao ano de 2004, quando testes de segurança genética ainda não eram obrigatórios, de acordo com a Resolução nº 90/2004 da ANVISA. Desta forma, o objetivo deste trabalho foi avaliar o potencial genotóxico de anti-hipertensivos distribuídos pela Farmácia Popular em células leucocitárias humanas, haja vista que são fármacos amplamente utilizados e se faz necessários maiores estudos que garantam a segurança genotoxicológica dos mesmos. Os testes foram desenvolvidos a partir de culturas celulares tratadas com cinco diferentes concentrações dos anti-hipertensivos, sendo avaliados parâmetros genotoxicológicos – viabilidade celular e índice de dano ao DNA (teste Cometa), e parâmetros mutagênicos – teste de micronúcleo e instabilidade cromossômica numérica. Os resultados mostram que captopril e maleato de enalapril foram capazes de diminuir a viabilidade celular e causar danos ao DNA conforme o aumento da dose, e que, o atenolol foi capaz de também diminuir a viabilidade celular de acordo com o aumento da dose. A hidroclorotiazida também mostrou causar dano ao DNA, porém esse dano ocorreu de forma igual para as cinco doses. Quanto aos parâmetros mutagênicos, nenhum dos seis anti-hipertensivos testados e, em nenhuma das cinco concentrações foi capaz de causar alterações mutagências. / Hypertension is an clinical condition of the multifactorial occurrence, the most frequent among chronic diseases not transferable in Brazil. It is characterized by increase and maintenance blood pressure levels above 140mmHg (sistolic pressure) and 90mmHg (diastolic pressure). It i also the most aggravating in the cardiovascular complications and it is associated with the appearance of others comorbidities. The WHO estimes that 40% of the world population over 25 years old is hypertensive, being located mostly in countries where income and educations levels are lower. After the diagnosed, hypertension must be treated with changes in the life style and drugs that maintain pressure levels controled, therefore, several classes of antihypertensive are used in this treatment. Aiming to expand access to basic drugs and allow a better adhesion to treatment, the federal government created in 2004 the “Farmácia Popular do Brasil” Program, an association among government and public and private institutions to provide the people medications for control of the hypertension, diabetes, asthma, dyslipidemia, contraceptives, etc, free or subsidized form by up to 90% of the value. To treat hypertension, the “Farmácia Popular do Brasil” Program distributes of free form antihypertensive – atenolol, captopril, propranolol hydrochloride, hydrochlorotiazhide, losartan and enalapril maleate, all these being released before the year 2004, when genetic safety tests still not required, according to Resolution nº 90/2004 of ANVISA. Thus, the objective this work was to evaluate the genotoxic potencial of the antihypertensives distributed by “Farmácia Popular” in human leukocytes cells, considering that they are widely used drugs and it is necessary larger studies that ensure the genotoxicology their safety. The tests are desenvolved from cell cultures treated with five different concentrations of the antihypertensives, being evaluated genotoxicological parameters – cell viability and DNA damage index, and mutagenic parameters – micronucleus test and numerical chromossomal aberrations. The results showed that captopril and enalapril maleate were able to reduce cell viability and cause damage to DNA wiht increasing dose. The hydrochlorothiazide also showed to cause DNA damage, but, this damage occorred equallity for five doses. As for mutagenic parameters , none of the six antihypertensives tested and, none of the five concentrations were capable to cause mutagenic changes.
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Ecosystem health at the texas coastal bend: a spatial analysis of exposure and responseBissett, Wesley Thurlow, Jr. 15 May 2009 (has links)
This dissertation investigated locational risks to ecosystem health associated with
proximity to industrial complexes. The study was performed at the behest of ranchers
and citizens living and working down-prevailing wind from the Formosa Plastics, Inc.
and ALCOA facilities located in Calhoun County, Texas. Concerns expressed were for
potential genotoxicity resulting from exposure to complex chemical mixtures released by
the facilities. Exposure assessment of the marine environment was performed with
sediments and oysters from Lavaca Bay being analyzed. Numerous chemicals were
found to be present at concentrations considered likely to result in adverse responses in
exposed populations. Bayesian geostatistical analysis was performed to determine if the
concentrations were affected by a spatial process. Mercury and polycyclic aromatic
hydrocarbons were the most notable of the chemicals found to be present at elevated
concentrations and affected by a spatial process. Evaluation of maps generated from
spatial modeling revealed that proximity to ALCOA resulted in elevated risks for
exposure to harmful concentrations of pollutants. Genotoxicity was measured in two
sentinel species. Oysters (Crassostrea virginica) were utilized for evaluation of the
marine environment and cattle (Bos taurus and Bos taurus crossbred cattle) were chosen
for evaluation of the terrestrial environment. Chromosomal aberration analysis was
performed on oyster hematocytes. Analysis of the results failed to demonstrate the
presence of an important generalized spatial process but some specific locations close to
the ALCOA plant had elevations in this measure of genotoxicity. Stress as measured by
the lysosomal destabilization assay was also performed on oyster hematocytes. These results were found to be affected by a significant spatial process with the highest degree
of destabilization occurring in close proximity to ALCOA. Genotoxicity in cattle was
evaluated with the single cell gel electrophoresis assay and chromosomal aberration
analysis. Bayesian geostatistical analyis revealed the presence of important spatial
processes. DNA-protein cross-linkage was the most notable with a strong indication of
increased damage down-prevailing wind from the industrial complexes. Results
indicated that proximity to industrial facilities increased the risk for harmful exposures,
genotoxicity, and lysosomal destabilization.
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Environmental toxicity of complex chemical mixturesGillespie, Annika Margaret 15 May 2009 (has links)
Complex chemical mixtures may be released into the environment from a variety
of sources including hazardous waste sites. Components of chemical mixtures and their
metabolites may be genotoxic leading to cancer and heritable gene mutations. Chemical
analysis alone does not always provide the most accurate information from which to
estimate the risk of adverse effects associated with exposure to mixtures. Current
methods to estimate the human health risk for complex mixtures assume additive effects
of the components. Although it is assumed that this approach is protective of human and
ecological health, it is also recognized that chemical mixtures may induce a variety of
interactions including potentiation, synergism, and antagonism. A combined testing
protocol, using chemical analysis coupled with a battery of in vitro, in vivo, and in situ
bioassays, provides the most accurate information from which to estimate risk. Such a
combined testing protocol provides information to describe the major organic and
inorganic constituents, as well as the pharmacokinetics and potential interactions of
chemical mixtures. This research was conducted to investigate the potential genotoxic
effects of complex chemical mixtures of polycyclic aromatic hydrocarbons (PAHs) and
polychlorinated aromatics (PCA) using microbial bioassays (Salmonella/microsome
assay and the E. coli prophage induction assay), the 32P-postlabeling assay in mice, and
in situ measurements of genotoxicity using flow cytometry. Samples of environmental
media and wildlife tissues were collected from four National Priority List Superfund
sites within the United States. In general, chemical analysis was not always predictive
of mixture toxicity. Although biodegradation reduced the concentration of total and
carcinogenic PAHs in soils and groundwater, the genotoxicity of extracts from environmental media did not display a corresponding reduction. Mixtures of
polychlorinated biphenyls (PCBs) extracted from sediments were found to inhibit the
genotoxicity of PAH mixtures when administered dermally to rodents. This inhibition
exhibited a dose-response relationship, with the adduct frequency reduced at increasing
doses of sediment extract. Finally, PAH concentrations in environmental media and
tissues were found to correlate with DNA damage in wildlife receptors. An integrated
approach, combining in vitro and in vivo methods to characterize genotoxicity provides
more accurate information from which to estimate uptake and risk associated with
exposure to complex mixtures and should be considered in both the human and
ecological risk assessment process.
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Ecosystem health at the Texas coastal bend: a spatial analysis of exposure and responseBissett, Wesley Thurlow, Jr. 10 October 2008 (has links)
This dissertation investigated locational risks to ecosystem health associated with
proximity to industrial complexes. The study was performed at the behest of ranchers
and citizens living and working down-prevailing wind from the Formosa Plastics, Inc.
and ALCOA facilities located in Calhoun County, Texas. Concerns expressed were for
potential genotoxicity resulting from exposure to complex chemical mixtures released by
the facilities. Exposure assessment of the marine environment was performed with
sediments and oysters from Lavaca Bay being analyzed. Numerous chemicals were
found to be present at concentrations considered likely to result in adverse responses in
exposed populations. Bayesian geostatistical analysis was performed to determine if the
concentrations were affected by a spatial process. Mercury and polycyclic aromatic
hydrocarbons were the most notable of the chemicals found to be present at elevated
concentrations and affected by a spatial process. Evaluation of maps generated from
spatial modeling revealed that proximity to ALCOA resulted in elevated risks for
exposure to harmful concentrations of pollutants. Genotoxicity was measured in two
sentinel species. Oysters (Crassostrea virginica) were utilized for evaluation of the
marine environment and cattle (Bos taurus and Bos taurus crossbred cattle) were chosen
for evaluation of the terrestrial environment. Chromosomal aberration analysis was
performed on oyster hematocytes. Analysis of the results failed to demonstrate the
presence of an important generalized spatial process but some specific locations close to
the ALCOA plant had elevations in this measure of genotoxicity. Stress as measured by
the lysosomal destabilization assay was also performed on oyster hematocytes. These results were found to be affected by a significant spatial process with the highest degree
of destabilization occurring in close proximity to ALCOA. Genotoxicity in cattle was
evaluated with the single cell gel electrophoresis assay and chromosomal aberration
analysis. Bayesian geostatistical analyis revealed the presence of important spatial
processes. DNA-protein cross-linkage was the most notable with a strong indication of
increased damage down-prevailing wind from the industrial complexes. Results
indicated that proximity to industrial facilities increased the risk for harmful exposures,
genotoxicity, and lysosomal destabilization.
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Avaliação do potencial fotoprotetor de extratos de musgos e investigação de seus riscos toxicológicos / Evaluation of potential photoprotective of moss extracts and investigation of their toxicological risksAndréia da Silva Fernandes Campos 04 March 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / A radiação ultravioleta (UV) induz diversos efeitos nocivos nos organismos e a quantidade desta radiação que atinge a biosfera é afetada pela concentração de ozônio, latitude, altitude, clima e reflexão especular. As respostas de briófitas em relação aos efeitos da radiação UV e a presença de compostos que absorvem esta radiação têm sido estudadas. Sanionia uncinata, Holomitriopsis laevifolia e Leucobryum laevifolium são espécies de musgos encontrados em locais expostos a alta incidência de radiação UV e com habitats distintos. Considerando que as respostas de musgos contra os efeitos da radiação UV e seus mecanismos de proteção ainda são pouco caracterizados, o objetivo deste estudo foi investigar o potencial fotoprotetor e possíveis riscos toxicológicos associados aos extratos dos musgos S. uncinata, proveniente da Antártica e H. laevifolia e L. laevifolium, proveniente do Amazonas. Seus extratos metanólico (EM), aquoso (EA), hidroalcoólico (EH) e etanólico (EE) foram estudados com a caracterização química por absorção ao UV e visível e pela cromatografia líquida de alta eficiência; quantificação do índice total de compostos fenólicos; determinação da capacidade captadora do radical 2,2-difenil-1-picril-hidrazila a fim de avaliar as atividades antioxidantes; avaliação do potencial de fotoproteção cutânea pela determinação do fator de proteção solar; avaliações do potencial mutagênico e citototóxico, através do ensaio de Salmonella/microssoma, utilizando as cepas TA97, TA98, TA100, TA102 e TA104; do potencial fotomutagênico através do ensaio de fotomutagenicidade, usando as cepas TA102 e TA104; e investigação dos efeitos genotóxicos e fotogenotóxicos, pelo ensaio de micronúcleo e fotomicronúcleo, respectivamente, usando diferentes linhagens celulares estabelecidas. Foram encontradas atividades fotoprotetoras e antioxidantes e observou-se que os extratos se apresentaram singulares devido a sua composição química. Os resultados fotoprotetores, além dos mutagênicos/fotomutagênicos, genotóxicos/fotogenotóxicos e suas respectivas avaliações citotóxicas também permitiram selecionar extratos e suas concentrações, como promissores candidatos em fotoproteção Assim, os EA e EH de H. laevifolia e L. laevifolium apresentam, no geral, os resultados mais significativos, tornando-se potenciais para avaliações refinadas em fotoproteção e na separação de componentes que possam levar a futuras aplicações como antioxidantes e protetores solares ou como adjuvantes. / The ultraviolet radiation (UV) induces many harmful effects in all living organisms and the amount of this radiation that reaching the ground is affected by many factors including ozone concentration, latitude, altitude, climate and specular reflection. The responses of bryophytes against the effects of UV radiation and the presence of compounds that absorb the UV region have been studied. Mosses Sanionia uncinata, Holomitriopsis laevifolia and Leucobryum laevifolium are found in locations exposed to UV at high levels of radiation and in different habitats. Whereas that the responses of mosses against the effects of UV radiation and their protection systems are poorly characterized yet, the aim of this study was to investigate photoprotective potential and possible toxicological risks associated with extracts of mosses S. uncinata (from Antarctica) and H. laevifolia and L. laevifolium (from Amazônia). Methanol (ME), aqueous (AE), hydroalcoholic (HE) and ethanolic (EE) were studied by: chemical characterization by UV/visible spectrophotometry and by High performance liquid chromatography; phenolic content estimation; 2,2-diphenyl-1-picrylhydrazyl scavenging activity; potential of skin photoprotection by in vitro determination of sun protection factor; the mutagenic potential, and cytotoxic by Salmonella/microsome assay, using the TA97, TA98, TA100, TA102 and TA104 strains; photomutagenic potential by photomutagenicity test, using TA102 and TA104 strains and; investigation of genotoxic and photogenotoxic effects by micronucleus test and photo-micronucleous assay, respectively, using different established cell lines. Photoprotective and antioxidant activities were found and it was observed that the extracts showed strong uniqueness due to its chemical composition. From the photoprotective, mutagenic/photomutagenic and genotoxic/photogenotoxic results and their cytotoxic evaluations it was possible to select extracts and their concentrations as promising candidates for photoprotection. Thus, the EA and EH of H. laevifolia and L. laevifolium demonstrated the most significant results, becoming potential for refined evaluations in photoprotection and separating components that can lead to future applications such as sunscreens and antioxidants or as adjuvants.
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Investigating the role of oxidative stress in the generation of plausibly misleading positive results for in vitro genotoxicity generated by polyphenolic antioxidantsAddinsell, Christopher January 2015 (has links)
Phenolic antioxidants reduce the effect of oxidative stress within cells. They are found in a various fruits, vegetables and as food additives to reduce spoilage. Consumption of antioxidants by humans has been linked with increased lifespan and reduced incidence of cancer and cardiovascular disorders (Cabrera et al. 2006; Kuriyama 2008). In cultured mammalian cells however, some of these phenolic antioxidants have been reported to generate reactive oxygen species (ROS), leading to chromosomal breakage (Long et al. 2007; Long & Halliwell 2001). It is clear then, that amongst this group of compounds, in vitro toxicological study is not a reliable prediction of human hazard. It is for this reason that the work described in this thesis was undertaken: the principal aim was to gain a better understanding of the reasons underlying this contradiction. It has been suggested that excessive ROS generated in vitro might be a result of the higher levels of oxygen (~20%) compared to (1-7%) in vivo: (Yusa et al. 1984; Turrens et al. 1982). With clearer understanding, new experimental approaches might be taken to highlight or reduce positive in vitro genotoxicity test results that might be considered misleading. A diverse set of test compounds was first chosen. It included polyphenolic (PPA), monophenolic (MPA) and non-phenolic antioxidants (NPA), in addition to mechanistically characterised oxidants, genotoxins and cytotoxic, non-genotoxins as controls. Genotoxicity was assessed in vitro using the GADD45a, GFP reporter assay and in silico using Derek Nexus™. Amongst the 19 antioxidants assessed, the 11 of 12 of PPAs, 0 of 4 MPAs and 1 of 3 NPAs (ethoxyquin) produced positive results in vitro and 8 of 12 PPAs generated alerts of at least plausible genotoxicity in silico. To discover whether these results were the result of cellular hyperoxia-promoted generation of physiologically irrelevant ROS in cells, genotoxicity was reassessed in the presence of 1 and 5% oxygen. This reduced oxygen exposure had no effect upon the qualitative result for any of the assessed compounds and a negligible effect upon the dose at which any positive result was produced. An assessment of the ability of antioxidants to generate potentially genotoxic ROS within cells was carried out using the intracellular fluorescent dye, dichlorofluorescin diacetate (DCFH-DA). 10 of 12 PPAs, 0 of 4 MPAs and 1 of 3 NPAs (ethoxyquin) were shown to increase the level of ROS within TK6 human lymphoblastoid cells within 4 hours of compound exposure. Within this same timeframe, the mitochondrial membranes in cells treated with 10 of 12 PPAs, 2 of 4 MPAs and 1 of 3 NPAs (ethoxyquin) were shown to become depolarised using JC-1 dye. It was unclear however, whether mitochondrial membrane depolarisation was a cause or a consequence of ROS generation within the cells. In order to assess whether the increase in intracellular ROS led to an increase in oxidised DNA within treated cells, 8-oxoguanine (8-OG) was quantified using a FITC conjugated anti8-OG antibody. This assessment revealed that levels of the oxidised base were only increased in cells exposed to two of the 12 PPAs (quercetin and resorcinol). The level of 8OG detected was lower than the vehicle control for cells treated with 10 of the 15 antioxidants. One interpretation of this is that these agents induce the repair pathway for oxidative damage, which leads to a lower level of oxidised DNA bases in the genome. The results showed that while a large proportion of PPAs produce genotoxic results in vitro and lead to increased levels of ROS, the amount of oxidised DNA is not higher in treated cells. This would suggest the presence of a different mechanism for the observed genotoxicity.
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Influência do tempo após manipulação na citotoxicidade e genotoxicidade de diferentes cimentos endodônticos /Oliveira, Tatiana Rocha de. January 2011 (has links)
Orientador: Carlos Henrique Ribeiro Camargo / Banca: Cácio de Moura Netto / Banca: Marcia Carneiro Valera / Resumo: Objetivo deste estudo foi avaliar a citotoxicidade e a genotoxidade de quatro cimentos endodônticos: AH Plus (Dentsply De Trey, Alemanha); Endo Rez (Ultradent, USA); RoekoSeal (Coltene Whaledent, Alemanha) e o Cimento experimental à base de óleo-resina de Copaiba (Brasil). A avaliação foi realizada em três diferentes tempos após manipulação: 0h, 12h e 24h. Os espécimes foram preparados, deixados por 12 e 24h em estufa (37 °C a 100% umidade a 5% de CO2) e colocados em contato com meio de cultura (82,4 mm2 superfície/ml) por 24 h. Células V79 foram expostas à diferentes diluições dos cimentos por 24 h e a viabilidade celular foi mensurada pelo teste de MTT em espectrofotômetro. Para o teste de genotoxicidade os extratos que apresentaram concentrações de citototoxicidade média foram selecionados para o teste cometa após 24 h de exposição. A viabilidade celular e o dano ao DNA foram comparados aos grupos controles e analisados pelos testes de Kruskal-Wallis e Dunn (p<0,05). No teste de citotoxicidade, todos os cimentos apresentaram diferença significativa em relação ao controle, com exceção do RoekoSeal. A viabilidade celular de acordo com cimento utliizado pode ser classificada da maior toxicidade para a menor seguindo: EndoREZ > AH Plus > Copaíba > RoekoSeal. O dano ao DNA verificado no teste cometa pode ser classificado do maior para o menor em: EndoREZ > RoekoSeal > AH Plus > Copaíba. Conclui-se que o cimento EndoREZ é citotóxico e genotóxico nos tempos e diluições estudadas / Abstract: The aim of this study was to evaluate cytotoxicity and the genotoxicity of four different root canal sealers, AH Plus (Dentsply De Trey, Germany); Endo REZ (Ultradent, USA); RoekoSeal (Coltene Whaledent, Germany) and the experimental root canal sealer based on Copaiba oil-resin sealer (Brazil). The evaluation of the materials was performed after three different times of manipulation: 0h, 12h and 24h. The specimens were prepared, incubated in a humidified incubator (37°C with 5% CO2 in air for 12h and 24h) and them put in contact with the culture medium (82,4 mm2surface/ml) during 24h. V79 cells were exposed at different dilutions of the sealers during 24h and the cell's viability was measured by the MTT test in a spectrophotometer. For the genotoxicity tests, the extracts from the concentrations with medium citotoxicity were selected for the comet assay after 24h of exposure. The cellular viability and the DNA damage were compared with the control groups and analyzed by the tests of Kruskal-Wallis and Dunn (p<0,05). The citotoxicity test showed that all root canal sealers showed a statistically significant difference when compared with the control group, with the exception of the RoekoSeal. The ranking of cell's viability according with sealer utilized from the most to the least toxicic material was: EndoRez > AH Plus > Copaíba > RoekoSeal. The ranking of DNA damage verified at the comet assay, from the most to the least was: EndoREZ > RoekoSeal > AH Plus > Copaíba. It was conclude that, at the times and dilutions studied, the EndoREZ sealer is genotoxic and citotoxic / Mestre
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Análise da toxicidade e da mutagenicidade de um solo de landfarming, proveniente de um refinaria de petróleo, antes e depois de processos que visam estimular a biodegradação de hidrocarbonetos /Souza, Tatiana da Silva. January 2010 (has links)
Orientador: Carmem Silvia Fontanetti Christofoletti / Banca: Patricia Pasquali Parise Maltempi / Banca: José Augusto de Oliveira David / Banca: Maria Aparecida Marin-Morales / Banca: Elaine Cristina Mathias da Silva Zacarin / Resumo: O sistema de biorremediação denominado landfarming tem sido utilizado por refinarias de petróleo para dispor e tratar, em grandes áreas de solo, localizadas na própria indústria, o resíduo sólido final gerado, que é composto por uma emulsão formada por água, diversas frações de hidrocarbonetos e metais. Contudo, em landfarmings, a biodegradação de algumas classes de hidrocarbonetos pode levar tempo, meses ou anos. Desse modo, tratamentos complementares podem ser utilizados, visando estimular o metabolismo microbiano, tais como a adição de agentes descompactantes e nutrientes no solo. O progresso da biorremediação pode ser acompanhado por meio de medidas da concentração dos contaminantes de interesse, pela análise do metabolismo microbiano e por meio de ensaios biológicos que mensuram as atividades tóxica, genotóxica e mutagênica das amostras avaliadas. O objetivo do presente trabalho foi investigar os efeitos da adição de dois resíduos agroindustriais, casca de arroz e vinhaça, na biorremediação, na genotoxicidade e na mutagenicidade de um solo de landfarming proveniente de uma refinaria de petróleo, por meio de análises químicas, taxa de CO2 liberado por microrganismos e por meio do teste de anormalidades mitóticas e cromossômicas na espécie vegetal Allium cepa. Também foi objetivo desse trabalho avaliar o potencial bioindicador do invertebrado terrestre Rhinocricus padbergi após exposição a amostras do landfarming desativado. Análises histológicas e histoquímicas no intestino médio e no corpo gorduroso perivisceral do diplópodo foram realizadas. Os resultados do presente trabalho mostraram que a casca de arroz, empregada como agente descompactante do solo, constitui uma alternativa economicamente viável para a biorremediação de resíduos derivados da indústria do petróleo. A adição desse material promoveu um aumento da quantidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The bioremediation system called landfarming has been used by petroleum refineries to dispose and treat, in large areas of soil, located in the own industry, the final solid residue generated, which is composed by an emulsion formed by water, several fractions of hydrocarbons and metals. However, in landfarmings, the biodegradation of some classes of hydrocarbons can take time, months or years. Thus, complementary treatments can be used in order to stimulate the microbial metabolism, such as addition of uncompressing agents and nutrients in the soil. The bioremediation progress can be monitored by measuring the concentrations of contaminants of interest, by the analysis of the microbial metabolism and by biological assays that measure toxic, genotoxic and mutagenic activities of the assessed samples. The aim of this study was to investigate the effects of adding two agroindustrial residues, rice hull and vinasse, in the bioremediation, genotoxicity and mutagenicity of a soil of landfarming from a petroleum refinery by chemical analyses, rate of CO2 released by microorganisms and by the mitotic and chromosomal abnormalities test in the plant species Allium cepa. It was also objective of this study assess the bioindicator potential of the terrestrial invertebrate Rhinocricus padbergi after exposure to deactivated landfarming samples. Histological and histochemical analyses of the midgut and fat body of this invertebrate were also carried out. The results of this study showed that rice hull, used as an uncompressing agent of the soil, constitutes an economically viable alternative for the bioremediation of residues derived from petroleum industry. The addition of this material promoted an increase in the quantity of CO2 released, decreased the concentration of total petroleum hydrocarbons (TPHs) of the landfarming soil and reduced its genotoxicity. On the contrary, vinasse... (Complete abstract click electronic access below) / Doutor
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Avaliação do potencial fotoprotetor de extratos de musgos e investigação de seus riscos toxicológicos / Evaluation of potential photoprotective of moss extracts and investigation of their toxicological risksAndréia da Silva Fernandes Campos 04 March 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / A radiação ultravioleta (UV) induz diversos efeitos nocivos nos organismos e a quantidade desta radiação que atinge a biosfera é afetada pela concentração de ozônio, latitude, altitude, clima e reflexão especular. As respostas de briófitas em relação aos efeitos da radiação UV e a presença de compostos que absorvem esta radiação têm sido estudadas. Sanionia uncinata, Holomitriopsis laevifolia e Leucobryum laevifolium são espécies de musgos encontrados em locais expostos a alta incidência de radiação UV e com habitats distintos. Considerando que as respostas de musgos contra os efeitos da radiação UV e seus mecanismos de proteção ainda são pouco caracterizados, o objetivo deste estudo foi investigar o potencial fotoprotetor e possíveis riscos toxicológicos associados aos extratos dos musgos S. uncinata, proveniente da Antártica e H. laevifolia e L. laevifolium, proveniente do Amazonas. Seus extratos metanólico (EM), aquoso (EA), hidroalcoólico (EH) e etanólico (EE) foram estudados com a caracterização química por absorção ao UV e visível e pela cromatografia líquida de alta eficiência; quantificação do índice total de compostos fenólicos; determinação da capacidade captadora do radical 2,2-difenil-1-picril-hidrazila a fim de avaliar as atividades antioxidantes; avaliação do potencial de fotoproteção cutânea pela determinação do fator de proteção solar; avaliações do potencial mutagênico e citototóxico, através do ensaio de Salmonella/microssoma, utilizando as cepas TA97, TA98, TA100, TA102 e TA104; do potencial fotomutagênico através do ensaio de fotomutagenicidade, usando as cepas TA102 e TA104; e investigação dos efeitos genotóxicos e fotogenotóxicos, pelo ensaio de micronúcleo e fotomicronúcleo, respectivamente, usando diferentes linhagens celulares estabelecidas. Foram encontradas atividades fotoprotetoras e antioxidantes e observou-se que os extratos se apresentaram singulares devido a sua composição química. Os resultados fotoprotetores, além dos mutagênicos/fotomutagênicos, genotóxicos/fotogenotóxicos e suas respectivas avaliações citotóxicas também permitiram selecionar extratos e suas concentrações, como promissores candidatos em fotoproteção Assim, os EA e EH de H. laevifolia e L. laevifolium apresentam, no geral, os resultados mais significativos, tornando-se potenciais para avaliações refinadas em fotoproteção e na separação de componentes que possam levar a futuras aplicações como antioxidantes e protetores solares ou como adjuvantes. / The ultraviolet radiation (UV) induces many harmful effects in all living organisms and the amount of this radiation that reaching the ground is affected by many factors including ozone concentration, latitude, altitude, climate and specular reflection. The responses of bryophytes against the effects of UV radiation and the presence of compounds that absorb the UV region have been studied. Mosses Sanionia uncinata, Holomitriopsis laevifolia and Leucobryum laevifolium are found in locations exposed to UV at high levels of radiation and in different habitats. Whereas that the responses of mosses against the effects of UV radiation and their protection systems are poorly characterized yet, the aim of this study was to investigate photoprotective potential and possible toxicological risks associated with extracts of mosses S. uncinata (from Antarctica) and H. laevifolia and L. laevifolium (from Amazônia). Methanol (ME), aqueous (AE), hydroalcoholic (HE) and ethanolic (EE) were studied by: chemical characterization by UV/visible spectrophotometry and by High performance liquid chromatography; phenolic content estimation; 2,2-diphenyl-1-picrylhydrazyl scavenging activity; potential of skin photoprotection by in vitro determination of sun protection factor; the mutagenic potential, and cytotoxic by Salmonella/microsome assay, using the TA97, TA98, TA100, TA102 and TA104 strains; photomutagenic potential by photomutagenicity test, using TA102 and TA104 strains and; investigation of genotoxic and photogenotoxic effects by micronucleus test and photo-micronucleous assay, respectively, using different established cell lines. Photoprotective and antioxidant activities were found and it was observed that the extracts showed strong uniqueness due to its chemical composition. From the photoprotective, mutagenic/photomutagenic and genotoxic/photogenotoxic results and their cytotoxic evaluations it was possible to select extracts and their concentrations as promising candidates for photoprotection. Thus, the EA and EH of H. laevifolia and L. laevifolium demonstrated the most significant results, becoming potential for refined evaluations in photoprotection and separating components that can lead to future applications such as sunscreens and antioxidants or as adjuvants.
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Estudo da mutagenicidade de metabólitos secundários liquênicos, utilizando o teste smart e ensaio cometa em células somáticas de Drosophila melanogasterAMORIM, Érima Maria de 23 February 2016 (has links)
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Previous issue date: 2016-02-23 / Capes / Liquens, organismos simbiontes notáveis, produzem metabólitos secundários amplamente citados por suas atividades biológicas. Entretanto, pouco se sabe a respeito do potencial tóxico ao DNA destes fenóis. Este trabalho avaliou o perfil mutagênico e genotóxico dos ácidos úsnico e divaricático, através do teste de Mutação e Recombinação Somática (SMART) e ensaio Cometa, utilizando Drosophila melanogaster como modelo experimental. Organismos descendentes dos cruzamentos entre as linhagens de D. melanogaster mwh e flr3, foram submetidos a diferentes concentrações do ácido úsnico (0,63, 1,26, 2,53, 5,05 e 10,11 mg/mL) e do ácido divaricático (0,32, 0,63, 1,26, 2,53, 5,05 e 10,11 mg/mL). Os resultados foram comparados com o controle positivo, mitomicina a 1,0 mg/mL e negativo, solventes de diluição. Os ensaios cometa foram realizados em hemócitos de D. melanogaster, linhagem Oregon-R. As células foram expostas às doses 0,63, 1,26, 2,53, 5,05 e 10,11 mg/mL do ácido úsnico e 0,32, 0,63, 1,26, 2,53 mg/mL do ácido divaricático. Os resultados foram comparados aos controles positivo de ciclofosfamida à 1mg/mL e negativo, mistura dos solventes. No ensaio de antigenotóxicidade foram utilizadas as mesmas concentrações de ácido úsnico acrescidas de mitomicina a 1mg/mL. Os resultados mostraram que as larvadas submetidas o ácido úsnico no teste SMART apresentaram uma sobrevivência superior a 70% dos indivíduos demonstrando, com níveis não significativos de genotoxicidade. Resultado semelhante ao ensaio Cometa. O ácido úsnico apresentou redução da mutagenicidade, em todas as concentrações quando associado à mitomicina, caracterizando efeito antigenotóxico. O ácido divaricático, no teste SMART, apresentou efeito tóxico nas concentrações 5,05 e 10,11 mg/mL e efeito genotóxico no ensaio cometa nas doses 0,32, 0,63, 1,26, 2,53. / Lichens are notable symbiontic organisms. They can produce phenolic compounds widely described because its biological properties. However a little bit is known about the mutagenic and genotoxic potential of these molecules. This study evaluated the mutagenic and genotoxic profile of the usnic and divaricatic acids through the Somatic Mutation and Recombination test (SMART) and the comet assay using the Drosophila melanogaster as experimental model. Organisms descendants of the crossing between strains of D. melanogaster mwh and flr3 were submitted to different concentrations of usnic (0,63, 1,26, 2,53, 5,05 and 10,11 mg/mL) and divaricatic acid (0,32, 0,63, 1,26, 2,53, 5,05 and 10,11 mg/mL). The results were obtained by comparation with the positive and negative standards, mitomicine (1,0 mg/mL) and the dilution solvent respectively. The comet assay were realized using hemocites of D. melanogaster from the Oregon – R strain. The cells were exposed to the different concentrations of the usnic and divaricatic acids. The results were obtained byu comparation with the positive and negative standards, cyclophosphamide (1,0 mg/mL) and the dilution solvent. The antigenotoxicity assay used the same concentrations of the usnic acid with the addition of the mitomicyn (1,0 mg/mL). The results demonstrated that the larvae submitted to usnic acid exhibit a higher survival rate of 70%, with no significant levels of genotoxicity. The same result was observed to the comet assay. The usnic acid showed a significant reduction of the mutagenicity in all the tested concentrations with the addition of mitomicyn characterizing an antigenotoxic effect. The divaricatic acid in the SMART test showed a toxic effect at the concentrations of 5,05 and 10,11 mg/mL and a genotoxic effect ant the concentrations of 0,32, 0,63, 1,26, 2,53 mg/mL.
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