Hajime Sui

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Additional file 6: of Negative and positive control ranges in the bacterial reverse mutation test: JEMS/BMS collaborative study

Figshare (2018)

Masayuki Kato Kei‐ichi Sugiyama Toshiro Fukushima Yasuyoshi Miura Takumi Awogi

Figure S5. Dose-response curves of revertant Escherichia coli strain WP2uvrA colonies following treatment with AF-2 in the absence of S9 mix (a), or with 2AA in the presence of S9 mix (b). Individual dose-response curves were generated using results produced by each participating laboratory in 2016 (different colors indicate different laboratories). The doses tested were 0.0025, 0.005, and 0.01 μg/plate for AF-2, and 2.5, 5.0, and 10 μg/plate for 2AA. (ODP 342 kb)

Negative control

Positive control

10.6084/m9.figshare.6084677

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Citations (0)

In vivo comet assay of acrylonitrile, 9-aminoacridine hydrochloride monohydrate and ethanol in rats

Mutation Research/Genetic Toxicology and Environmental Mutagenesis (2015)

Yuzuki Nakagawa Tomoyasu Toyoizumi Hajime Sui Ryo Ohta Fumiaki Kumagai

Comet Assay

Hydrochloride

10.1016/j.mrgentox.2015.04.001

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Citations (8)

Evaluation of In Vivo Mutagenicity by 2,4-Diaminotoluene and 2,6-Diaminotoluene in Liver of F344 gpt delta Transgenic Rat Dosed for 28 Days: A Collaborative Study of the gpt delta Transgenic Rat Mutation Assay

Genes and Environment (2012)

Hajime Sui Ryo Ohta Toshiyuki Shiragiku Ayaka Akahori Kenichiro Suzuki

10.3123/jemsge.34.25

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Citations (6)

O11-18 Intragenic Recombinations by Chemicals using Pun Mice

The Journal of Toxicological Sciences (2001)

Tohru Shibuya Masako Sato Tomomi Morimura Hirotaka Matsaumoto Hajime Sui

Pun

Source

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Evaluation of the repeated-dose liver and gastrointestinal tract micronucleus assays with 22 chemicals using young adult rats: Summary of the collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/The Japanese Environmental Mutagen Society (JEMS) – Mammalian Mutagenicity Study Group (MMS)

Mutation Research/Genetic Toxicology and Environmental Mutagenesis (2015)

Shuichi Hamada Wakako Ohyama Rie Takashima Keisuke Shimada Kazumi Matsumoto

The repeated-dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect hepatocarcinogens. We conducted a collaborative study to assess the performance of this assay and to evaluate the possibility of integrating it into general toxicological studies. Twenty-four testing laboratories belonging to the Mammalian Mutagenicity Study Group, a subgroup of the Japanese Environmental Mutagen Society, participated in this trial. Twenty-two model chemicals, including some hepatocarcinogens, were tested in 14- and/or 28-day RDLMN assays. As a result, 14 out of the 16 hepatocarcinogens were positive, including 9 genotoxic hepatocarcinogens, which were reported negative in the bone marrow/peripheral blood micronucleus (MN) assay by a single treatment. These outcomes show the high sensitivity of the RDLMN assay to hepatocarcinogens. Regarding the specificity, 4 out of the 6 non-liver targeted genotoxic carcinogens gave negative responses. This shows the high organ specificity of the RDLMN assay. In addition to the RDLMN assay, we simultaneously conducted gastrointestinal tract MN assays using 6 of the above carcinogens as an optional trial of the collaborative study. The MN assay using the glandular stomach, which is the first contact site of the test chemical when administered by oral gavage, was able to detect chromosomal aberrations with 3 test chemicals including a stomach-targeted carcinogen. The treatment regime was the 14- and/or 28-day repeated-dose, and the regime is sufficiently promising to incorporate these methods into repeated-dose toxicological studies. The outcomes of our collaborative study indicated that the new techniques to detect chromosomal aberrations in vivo in several tissues worked successfully.

Clastogen

10.1016/j.mrgentox.2015.01.001

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Citations (75)

Epigenetic reprogramming of the human H19 gene in mouse embryonic cells does not erase the primary parental imprint

Genes to Cells (1998)

Kohzoh Mitsuya Makiko Meguro Hajime Sui Thomas C. Schulz Hiroyuki Kugoh

Background Genomic imprinting in mammals is thought to result from epigenetic modifications to chromosomes during gametogenesis, which leads to differential allelic expression during development. There is a requirement for an appropriate experimental system to enable the analysis of the mechanisms of genomic imprinting during embryogenesis. Results To develop a novel in vitro system for studying the molecular basis of genomic imprinting, we constructed mouse cell lines containing either a paternal or maternal human chromosome 11, by microcell‐mediated chromosome transfer. Allele‐specific expression and DNA methylation studies revealed that the imprinting status of the human H19 gene was maintained in mouse A9 mono‐chromosomal hybrids. Each parental human chromosome was introduced independently into mouse near‐diploid immortal fibroblasts (m5S) and two embryonal carcinoma (EC) cell lines (OTF9‐63 and P19). The paternal allele of human H19 remained in a repressed state in m5S cells, but was de‐repressed in both EC cells. The paternal H19 allele was demethylated extensively in OTF9‐63 cells, whereas the only alteration in P19 hybrids was de novo methylation on both alleles in the 3′ region. Following in vitro differentiation, the expressed paternal H19 allele was selectively repressed in differentiated derivatives of EC hybrids. Conclusion These results indicated that human imprint marks could function effectively in mouse cells, and that the imprinting process was epigenetically reprogrammed in embryonal carcinoma cells, without erasure of the primary imprint that marked the parental origin. Therefore, these mono‐chromosomal hybrids could provide a valuable in vitro system to study the mechanisms involved in the regulation of imprinted gene expression.

Genomic Imprinting

Reprogramming

Imprinting (psychology)

10.1046/j.1365-2443.1998.00183.x

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Citations (15)

In vivo photochemical skin micronucleus test using a sunlight simulator: Detection of 8-methoxypsoralen and benzo[a]pyrene in hairless mice

Mutation Research/Genetic Toxicology and Environmental Mutagenesis (2007)

Takumi Hara Takashi Nishikawa Hajime Sui Kumiko Kawakami Hirotaka Matsumoto

Hairless

Sunlight

10.1016/j.mrgentox.2007.03.007

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Citations (15)

Additional file 3: of Negative and positive control ranges in the bacterial reverse mutation test: JEMS/BMS collaborative study

Figshare (2018)

Masayuki Kato Kei‐ichi Sugiyama Toshiro Fukushima Yasuyoshi Miura Takumi Awogi

Figure S2. Dose-response curves of revertant Salmonella Typhimurium strain TA98 colonies following treatment with AF-2 in the absence of S9 mix (a), or treatment with 2AA in the presence of S9 mix (b). Individual dose-response curves were generated using results produced by each participating laboratory in 2016 (different colors indicate different laboratories). The doses tested were 0.025, 0.05, and 0.1 μg/plate for AF-2, and 0.125, 0.25, and 0.5 μg/plate for 2AA. (ODP 434 kb)

Positive control

Negative control

10.6084/m9.figshare.6084626

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Citations (0)

Intragenic recombination within the p allele of the pink-eyed dilution locus in pre-melanocytes and primordial germ cells of embryonic mice treated with N-ethyl-N-nitrosourea

Mutation Research/Genetic Toxicology and Environmental Mutagenesis (2021)

Tohru Shibuya Wakako Takeda-Endo Takumi Hara Hajime Sui Yukiharu Horiya

Pun

Mitotic crossover

10.1016/j.mrgentox.2021.503426

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