The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Raphaël Terreux - One of the best experts on this subject based on the ideXlab platform.
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Ames Test prediction on high energy molecules by on the fly qsar otf qsar
Propellants Explosives Pyrotechnics, 2017Co-Authors: Charlotte Alliod, Julie-anne Chemelle, Guy Jacob, Raphaël TerreuxAbstract:In collaboration with Herakles, a research program was set up to have, in the future, optimized tools for predicting the toxicity of High Energy Molecules (HEM). Because of the number of mutagenicity Tests commonly use in the society, a variety of internationally agreed Testing protocols on chemicals was set up, described by REACh (Registration, Evaluation, Authorization and Restriction of Chemicals) and OECD (Organization for the Economic Cooperation and Development). The first Test described for the mutagenicity is the Ames Test. Several methods can be used to predict toxicity such as (Quantitative) Structure Activity Relationship [(Q)SAR] and “On-The-Fly” QSAR (OTF-QSAR). The aim of this paper is to evaluate the reliability of the SAR and the OTF-QSAR predictions in accordance with various similarities used. The goal is to obtain a good prediction tool for the Ames Test. The prediction tool is compared with softwares often used in the scientific community. It was found that the OTF-QSAR predictions were more accurate and increased the efficiency of predictions. The precision of the system increases as the degree of similarity increased. A new zone was discovered and the best similarity found and refined. At the end of the study, we validate the similarity information and the OTF-QSAR on HEM molecules.
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Ames Test Prediction on High Energy Molecules by On‐The‐Fly QSAR (OTF‐QSAR)
Propellants Explosives Pyrotechnics, 2016Co-Authors: Charlotte Alliod, Julie-anne Chemelle, Guy Jacob, Raphaël TerreuxAbstract:In collaboration with Herakles, a research program was set up to have, in the future, optimized tools for predicting the toxicity of High Energy Molecules (HEM). Because of the number of mutagenicity Tests commonly use in the society, a variety of internationally agreed Testing protocols on chemicals was set up, described by REACh (Registration, Evaluation, Authorization and Restriction of Chemicals) and OECD (Organization for the Economic Cooperation and Development). The first Test described for the mutagenicity is the Ames Test. Several methods can be used to predict toxicity such as (Quantitative) Structure Activity Relationship [(Q)SAR] and “On-The-Fly” QSAR (OTF-QSAR). The aim of this paper is to evaluate the reliability of the SAR and the OTF-QSAR predictions in accordance with various similarities used. The goal is to obtain a good prediction tool for the Ames Test. The prediction tool is compared with softwares often used in the scientific community. It was found that the OTF-QSAR predictions were more accurate and increased the efficiency of predictions. The precision of the system increases as the degree of similarity increased. A new zone was discovered and the best similarity found and refined. At the end of the study, we validate the similarity information and the OTF-QSAR on HEM molecules.
Toshio Kasamatsu - One of the best experts on this subject based on the ideXlab platform.
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Modified Ames Test using a strain expressing human sulfotransferase 1C2 to assess the mutagenicity of methyleugenol
Genes and Environment, 2016Co-Authors: Hiroshi Honda, Kazuyuki Minegawa, Yurika Fujita, Noriko Yamaguchi, Yoshihiro Oguma, Hansruedi Glatt, Naohiro Nishiyama, Toshio KasamatsuAbstract:Introduction Several alkenylbenzenes, including methyleugenol (ME), are present in a wide range of botanicals and exhibit carcinogenic and mutagenic properties. Negative results are generally obtained for alkenylbenzenes in standard in vitro genotoxicity Tests, including the Ames Test. A lack of mutagenicity observed in such Tests is thought to result from impaired metabolic activation of alkenylbenzenes via hydroxylation, with subsequent sulfoconjugation to its ultimate mutagenic or carcinogenic form. Although recent studies have reported the mutagenicity of hydroxylated ME metabolites in the Ames Test using modified TA100 strains expressing human sulfotransferases (SULTs), to our knowledge, the detection of ME mutagenicity has not yet been reported. Findings Using strain TA100-hSULT1C2, which expresses human SULT1C2, we optimized the protein content of S9 Mix and the pre-incubation time required to promote metabolic activation in the Ames Test. This procedure enabled us to obtain a positive response with ME. Conclusions We established Ames-Test conditions enabling the detection of ME-induced mutagenicity, using a strain expressing human SULT1C2 in the presence of induced-rat S9 Mix. This simple approach will help assess the mutagenicity of other alkenylbenzenes and related chemicals.
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Modified Ames Test using a strain expressing human sulfotransferase 1C2 to assess the mutagenicity of methyleugenol
Genes and Environment, 2016Co-Authors: Hiroshi Honda, Kazuyuki Minegawa, Yurika Fujita, Noriko Yamaguchi, Yoshihiro Oguma, Hansruedi Glatt, Naohiro Nishiyama, Toshio KasamatsuAbstract:Introduction Several alkenylbenzenes, including methyleugenol (ME), are present in a wide range of botanicals and exhibit carcinogenic and mutagenic properties. Negative results are generally obtained for alkenylbenzenes in standard in vitro genotoxicity Tests, including the Ames Test. A lack of mutagenicity observed in such Tests is thought to result from impaired metabolic activation of alkenylbenzenes via hydroxylation, with subsequent sulfoconjugation to its ultimate mutagenic or carcinogenic form. Although recent studies have reported the mutagenicity of hydroxylated ME metabolites in the Ames Test using modified TA100 strains expressing human sulfotransferases (SULTs), to our knowledge, the detection of ME mutagenicity has not yet been reported. Findings Using strain TA100-hSULT1C2, which expresses human SULT1C2, we optimized the protein content of S9 Mix and the pre-incubation time required to promote metabolic activation in the Ames Test. This procedure enabled us to obtain a positive response with ME. Conclusions We established Ames-Test conditions enabling the detection of ME-induced mutagenicity, using a strain expressing human SULT1C2 in the presence of induced-rat S9 Mix. This simple approach will help assess the mutagenicity of other alkenylbenzenes and related chemicals.
Hiroshi Honda - One of the best experts on this subject based on the ideXlab platform.
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Modified Ames Test using a strain expressing human sulfotransferase 1C2 to assess the mutagenicity of methyleugenol
Genes and Environment, 2016Co-Authors: Hiroshi Honda, Kazuyuki Minegawa, Yurika Fujita, Noriko Yamaguchi, Yoshihiro Oguma, Hansruedi Glatt, Naohiro Nishiyama, Toshio KasamatsuAbstract:Introduction Several alkenylbenzenes, including methyleugenol (ME), are present in a wide range of botanicals and exhibit carcinogenic and mutagenic properties. Negative results are generally obtained for alkenylbenzenes in standard in vitro genotoxicity Tests, including the Ames Test. A lack of mutagenicity observed in such Tests is thought to result from impaired metabolic activation of alkenylbenzenes via hydroxylation, with subsequent sulfoconjugation to its ultimate mutagenic or carcinogenic form. Although recent studies have reported the mutagenicity of hydroxylated ME metabolites in the Ames Test using modified TA100 strains expressing human sulfotransferases (SULTs), to our knowledge, the detection of ME mutagenicity has not yet been reported. Findings Using strain TA100-hSULT1C2, which expresses human SULT1C2, we optimized the protein content of S9 Mix and the pre-incubation time required to promote metabolic activation in the Ames Test. This procedure enabled us to obtain a positive response with ME. Conclusions We established Ames-Test conditions enabling the detection of ME-induced mutagenicity, using a strain expressing human SULT1C2 in the presence of induced-rat S9 Mix. This simple approach will help assess the mutagenicity of other alkenylbenzenes and related chemicals.
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Modified Ames Test using a strain expressing human sulfotransferase 1C2 to assess the mutagenicity of methyleugenol
Genes and Environment, 2016Co-Authors: Hiroshi Honda, Kazuyuki Minegawa, Yurika Fujita, Noriko Yamaguchi, Yoshihiro Oguma, Hansruedi Glatt, Naohiro Nishiyama, Toshio KasamatsuAbstract:Introduction Several alkenylbenzenes, including methyleugenol (ME), are present in a wide range of botanicals and exhibit carcinogenic and mutagenic properties. Negative results are generally obtained for alkenylbenzenes in standard in vitro genotoxicity Tests, including the Ames Test. A lack of mutagenicity observed in such Tests is thought to result from impaired metabolic activation of alkenylbenzenes via hydroxylation, with subsequent sulfoconjugation to its ultimate mutagenic or carcinogenic form. Although recent studies have reported the mutagenicity of hydroxylated ME metabolites in the Ames Test using modified TA100 strains expressing human sulfotransferases (SULTs), to our knowledge, the detection of ME mutagenicity has not yet been reported. Findings Using strain TA100-hSULT1C2, which expresses human SULT1C2, we optimized the protein content of S9 Mix and the pre-incubation time required to promote metabolic activation in the Ames Test. This procedure enabled us to obtain a positive response with ME. Conclusions We established Ames-Test conditions enabling the detection of ME-induced mutagenicity, using a strain expressing human SULT1C2 in the presence of induced-rat S9 Mix. This simple approach will help assess the mutagenicity of other alkenylbenzenes and related chemicals.
Tao Chen - One of the best experts on this subject based on the ideXlab platform.
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genotoxicity evaluation of titanium dioxide nanoparticles using the Ames Test and comet assay
Journal of Applied Toxicology, 2012Co-Authors: Robert S Woodruff, Yan Li, Michelle E Bishop, Yvonne M Jones, Fumiya Watanabe, Alexandru S Biris, Penelope Rice, Tong Zhou, Tao ChenAbstract:Titanium dioxide nanoparticles (TiO2-NPs) are being used increasingly for various industrial and consumer products, including cosmetics and sunscreens because of their photoactive properties. Therefore, the toxicity of TiO2-NPs needs to be thoroughly understood. In the present study, the genotoxicity of 10nm uncoated sphere TiO2-NPs with an anatase crystalline structure, which has been well characterized in a previous study, was assessed using the Salmonella reverse mutation assay (Ames Test) and the single-cell gel electrophoresis (Comet) assay. For the Ames Test, Salmonella strains TA102, TA100, TA1537, TA98 and TA1535 were preincubated with eight different concentrations of the TiO2-NPs for 4h at 37 C, ranging from 0 to 4915.2mg per plate. No mutation induction was found. Analyses with transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) showed that the TiO2-NPs were not able to enter the bacterial cell. For the Comet assay,TK6cellsweretreatedwith0-200mgml -1 TiO2-NPsfor24hat37 CtodetectDNAdamage.AlthoughtheTK6cellsdidtake up TiO2-NPs, no significant induction of DNA breakage or oxidative DNA damage was observed in the treated cells using the standard alkaline Comet assay and the endonuclease III (EndoIII) and human 8-hydroxyguanine DNA-glycosylase (hOGG1)- modified Comet assay, respectively. These results suggest that TiO2-NPs are not genotoxic under the conditions of the Ames Test and Comet assay. Published 2012. This article is a US Government work and is in the public domain in the USA.
Julie-anne Chemelle - One of the best experts on this subject based on the ideXlab platform.
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Ames Test prediction on high energy molecules by on the fly qsar otf qsar
Propellants Explosives Pyrotechnics, 2017Co-Authors: Charlotte Alliod, Julie-anne Chemelle, Guy Jacob, Raphaël TerreuxAbstract:In collaboration with Herakles, a research program was set up to have, in the future, optimized tools for predicting the toxicity of High Energy Molecules (HEM). Because of the number of mutagenicity Tests commonly use in the society, a variety of internationally agreed Testing protocols on chemicals was set up, described by REACh (Registration, Evaluation, Authorization and Restriction of Chemicals) and OECD (Organization for the Economic Cooperation and Development). The first Test described for the mutagenicity is the Ames Test. Several methods can be used to predict toxicity such as (Quantitative) Structure Activity Relationship [(Q)SAR] and “On-The-Fly” QSAR (OTF-QSAR). The aim of this paper is to evaluate the reliability of the SAR and the OTF-QSAR predictions in accordance with various similarities used. The goal is to obtain a good prediction tool for the Ames Test. The prediction tool is compared with softwares often used in the scientific community. It was found that the OTF-QSAR predictions were more accurate and increased the efficiency of predictions. The precision of the system increases as the degree of similarity increased. A new zone was discovered and the best similarity found and refined. At the end of the study, we validate the similarity information and the OTF-QSAR on HEM molecules.
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Ames Test Prediction on High Energy Molecules by On‐The‐Fly QSAR (OTF‐QSAR)
Propellants Explosives Pyrotechnics, 2016Co-Authors: Charlotte Alliod, Julie-anne Chemelle, Guy Jacob, Raphaël TerreuxAbstract:In collaboration with Herakles, a research program was set up to have, in the future, optimized tools for predicting the toxicity of High Energy Molecules (HEM). Because of the number of mutagenicity Tests commonly use in the society, a variety of internationally agreed Testing protocols on chemicals was set up, described by REACh (Registration, Evaluation, Authorization and Restriction of Chemicals) and OECD (Organization for the Economic Cooperation and Development). The first Test described for the mutagenicity is the Ames Test. Several methods can be used to predict toxicity such as (Quantitative) Structure Activity Relationship [(Q)SAR] and “On-The-Fly” QSAR (OTF-QSAR). The aim of this paper is to evaluate the reliability of the SAR and the OTF-QSAR predictions in accordance with various similarities used. The goal is to obtain a good prediction tool for the Ames Test. The prediction tool is compared with softwares often used in the scientific community. It was found that the OTF-QSAR predictions were more accurate and increased the efficiency of predictions. The precision of the system increases as the degree of similarity increased. A new zone was discovered and the best similarity found and refined. At the end of the study, we validate the similarity information and the OTF-QSAR on HEM molecules.