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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Mutagenic Activity of High-Energy Explosives; Contaminants of Concern at Military Training Sites

McAllister, Jennifer E. 24 August 2011 (has links)
The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.
2

The Mutagenic Activity of High-Energy Explosives; Contaminants of Concern at Military Training Sites

McAllister, Jennifer E. 24 August 2011 (has links)
The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.
3

The Mutagenic Activity of High-Energy Explosives; Contaminants of Concern at Military Training Sites

McAllister, Jennifer E. 24 August 2011 (has links)
The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.
4

The Mutagenic Activity of High-Energy Explosives; Contaminants of Concern at Military Training Sites

McAllister, Jennifer E. January 2011 (has links)
The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.
5

Comparação da mutagenicidade dos azo corantes Disperse Red 1, Disperse Orange 1 e Disperse Red 13 utilizando o teste de mutagenicidade com \'Salmonella\' / Comparison of the mutagenicity of the azo dyes Disperse Red 1, Disperse Orange 1 and Disperse Red 13 using Salmonella/microssome mutagenicity assay

Ferraz, Elisa Raquel Anastácio 10 July 2008 (has links)
Os azo corantes representam o maior grupo de corantes utilizados na indústria, principalmente no ramo têxtil. Sabe-se que grande parte desses produtos resiste aos sistemas de tratamento de efluente e assim, cerca de 10-15% dos corantes perdidos durante o processo de tingimento são lançados no efluente e atingem o meio ambiente. Alguns corantes desse grupo têm mostrado ser cancerígenos e mutagênicos para animais e humanos. Essa toxicidade se deve, em parte, à clivagem da ligação azo formando aminas aromáticas potencialmente cancerígenas. Ainda, a ação de sistema de metabolização nos grupamentos substituintes pode alterar a toxicidade destes compostos. Neste trabalho foram testados os azo corantes Disperse Orange 1 (4-(4--nitrofenilazo)difenilamina); pureza 96%; CAS no 2581-69-3), Disperse Red 1(N-etil-N(2-hidroxietil)-4-(4-nitrofenilazo)anilina; pureza 95%; CAS no. 2872-52-8) e Disperse Red 13 (2-[4-(2-cloro-4-nitrofenilazo)-N-etilfenilamino] etanol; pureza de 95%; CAS no 3180-81-2) usando o ensaio de mutagenicidade com Samonella. Foram utilizadas as linhagens tradicionais, TA98 e TA100 e suas respectivas derivadas com superprodução de nitroredutase e O-acetiltransferase, YG1041 e YG1042. Todos os corantes testados mostraram respostas mais altas com a linhagem TA98 em relação a TA100, o que sugere que esses compostos exercem seu efeito mutagênico principalmente por deslocamento do quadro de leitura do DNA. Para os três corantes, a resposta da linhagem YG1041 em relação a sua parental TA98 foi significativamente aumentada, mostrando a importância da nitroredutase e O-acetiltransferase na mutagenicidade desses corantes. Tal fato foi confirmado com as respostas da TA100 em relação a YG1042. O sistema de metabolização exógeno (S9) diminuiu a mutagenicidade de todos os corantes testados. Considerando os resultados obtidos com a linhagem YG1041, o corante Disperse Red 1 é o mais potente, seguido do Disperse Orange 1 e do Disperse Red 13. / Azo dyes constitute the largest group of colorants used in industry, mainly the textile one, and they pass through industrial wastewater treatment plants nearly unchanged due to their resistance to aerobic treatment. Therefore, it is estimated that 10-15% of the dyes are lost in the effluent during the dyeing process, reaching the environment. Some of these dyes have been shown to be carcinogenic and mutagenic to animals and humans. This toxic effect is, in part due to azo bond cleavage that forms potentially carcinogenic aromatic amines. The toxicity of the dyes can also be altered by the biotransformation of the substitutens. We tested the azo dyes Disperse Orange 1 (4-(4-Nitrophenylazo)diphenylamine); 96% purity; CAS number 2581-69-3), Disperse Red 1(N-Ethyl-N-(2-hydroxyethyl)-4-(4-nitrophenylazo)aniline; 95% purity; CAS number 2872-52-8) and Disperse Red 13 (2-[4-(2-Chloro-4-nitrophenylazo)-N-ethylphenylamino]ethanoll; 95% purity; CAS number 3180-81-2) using Salmonella/microssome mutagenicity assay. We used the traditional strains TA98 and TA100 and the strains with overproducing nitroreductase and O-acetyltransferase, YG1041 and YG1042, derivative of the TA 98 and TA100, respectively. All the dyes tested showed higher responses with the strain TA98 when compared with TA100, suggesting that these compounds induce mainly frameshift mutations. Moreover, we observed an increase in the mutagenicity with the overproducing nitroreductase and O-acetyltransferase strains, showing the importance of these enzymes in the mutagenicity of these dyes. In addition, for all the dyes the mutagenicity decreased after the S9 addition. According to mutagenic response with YG1041, Disperse Red 1 was the most potent, followed by Disperse Orange 1 and Disperse Red 13.
6

Comparação da mutagenicidade dos azo corantes Disperse Red 1, Disperse Orange 1 e Disperse Red 13 utilizando o teste de mutagenicidade com \'Salmonella\' / Comparison of the mutagenicity of the azo dyes Disperse Red 1, Disperse Orange 1 and Disperse Red 13 using Salmonella/microssome mutagenicity assay

Elisa Raquel Anastácio Ferraz 10 July 2008 (has links)
Os azo corantes representam o maior grupo de corantes utilizados na indústria, principalmente no ramo têxtil. Sabe-se que grande parte desses produtos resiste aos sistemas de tratamento de efluente e assim, cerca de 10-15% dos corantes perdidos durante o processo de tingimento são lançados no efluente e atingem o meio ambiente. Alguns corantes desse grupo têm mostrado ser cancerígenos e mutagênicos para animais e humanos. Essa toxicidade se deve, em parte, à clivagem da ligação azo formando aminas aromáticas potencialmente cancerígenas. Ainda, a ação de sistema de metabolização nos grupamentos substituintes pode alterar a toxicidade destes compostos. Neste trabalho foram testados os azo corantes Disperse Orange 1 (4-(4--nitrofenilazo)difenilamina); pureza 96%; CAS no 2581-69-3), Disperse Red 1(N-etil-N(2-hidroxietil)-4-(4-nitrofenilazo)anilina; pureza 95%; CAS no. 2872-52-8) e Disperse Red 13 (2-[4-(2-cloro-4-nitrofenilazo)-N-etilfenilamino] etanol; pureza de 95%; CAS no 3180-81-2) usando o ensaio de mutagenicidade com Samonella. Foram utilizadas as linhagens tradicionais, TA98 e TA100 e suas respectivas derivadas com superprodução de nitroredutase e O-acetiltransferase, YG1041 e YG1042. Todos os corantes testados mostraram respostas mais altas com a linhagem TA98 em relação a TA100, o que sugere que esses compostos exercem seu efeito mutagênico principalmente por deslocamento do quadro de leitura do DNA. Para os três corantes, a resposta da linhagem YG1041 em relação a sua parental TA98 foi significativamente aumentada, mostrando a importância da nitroredutase e O-acetiltransferase na mutagenicidade desses corantes. Tal fato foi confirmado com as respostas da TA100 em relação a YG1042. O sistema de metabolização exógeno (S9) diminuiu a mutagenicidade de todos os corantes testados. Considerando os resultados obtidos com a linhagem YG1041, o corante Disperse Red 1 é o mais potente, seguido do Disperse Orange 1 e do Disperse Red 13. / Azo dyes constitute the largest group of colorants used in industry, mainly the textile one, and they pass through industrial wastewater treatment plants nearly unchanged due to their resistance to aerobic treatment. Therefore, it is estimated that 10-15% of the dyes are lost in the effluent during the dyeing process, reaching the environment. Some of these dyes have been shown to be carcinogenic and mutagenic to animals and humans. This toxic effect is, in part due to azo bond cleavage that forms potentially carcinogenic aromatic amines. The toxicity of the dyes can also be altered by the biotransformation of the substitutens. We tested the azo dyes Disperse Orange 1 (4-(4-Nitrophenylazo)diphenylamine); 96% purity; CAS number 2581-69-3), Disperse Red 1(N-Ethyl-N-(2-hydroxyethyl)-4-(4-nitrophenylazo)aniline; 95% purity; CAS number 2872-52-8) and Disperse Red 13 (2-[4-(2-Chloro-4-nitrophenylazo)-N-ethylphenylamino]ethanoll; 95% purity; CAS number 3180-81-2) using Salmonella/microssome mutagenicity assay. We used the traditional strains TA98 and TA100 and the strains with overproducing nitroreductase and O-acetyltransferase, YG1041 and YG1042, derivative of the TA 98 and TA100, respectively. All the dyes tested showed higher responses with the strain TA98 when compared with TA100, suggesting that these compounds induce mainly frameshift mutations. Moreover, we observed an increase in the mutagenicity with the overproducing nitroreductase and O-acetyltransferase strains, showing the importance of these enzymes in the mutagenicity of these dyes. In addition, for all the dyes the mutagenicity decreased after the S9 addition. According to mutagenic response with YG1041, Disperse Red 1 was the most potent, followed by Disperse Orange 1 and Disperse Red 13.

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