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Kanmaz HG, Okur N, Dilli D, Yeşilyurt A, Oğuz ŞS. The effect of phototherapy on sister chromatid exchange with different light density in newborn hyperbilirubinemia. Turk Arch Pediatr 2017; 52:202-207. [PMID: 29483799 DOI: 10.5152/turkpediatriars.2017.5143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 06/20/2017] [Indexed: 11/22/2022]
Abstract
Aim Concerns of possible genotoxic effects of hyperbilirubinemia and phototherapy were raised from experimental and observational studies in neonates. The purpose of this study was to assess the effect of hyperbilirubinemia and phototherapy with three different methods on DNA damage by investigating sister chromatid exchange frequency. Material and Methods Patients whose gestational ages were >37 weeks and bilirubin levels above phototherapy limits were enrolled into three groups and each group was planned to receive 25 babies. Group 1 received enhanced light-emitting diode phototherapy, group 2 had light-emitting diode phototherapy, and group 3 received conventional phototherapy. Infants with hyperbilirubinemia but did not require phototherapy comprised the control group, which was subdivided into two groups regarding bilirubin levels (<or>10mg/dL). Blood samples were collected before and after phototherapy for sister chromatid exchange frequency and samples were examined by a biologist who was blinded to the study groups. Results The mean pre-treatment sister chromatid exchange frequency was 1.41±0.34/cell, post-treatment 2.65±0.68/cell, and 1.61±0.61/cell for the control group (p<0.05). A statistically significant increase in sister chromatid exchange frequency after phototherapy was observed in all three intervention groups (p values: 0.01, 0.01, and 0.008, respectively). When the treatment groups were compared with each other in terms of irradiance, no significant difference was found (p=0.08). Conclusions Phototherapy causes an increase in the frequency of sister chromatid exchange regardless of the irradiance. Phototherapy could have some genotoxic adverse effects on chromosomes; however, further investigations are warranted to enlighten as to whether these effects are permanent or clinically important.
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Affiliation(s)
- Hayriye Gözde Kanmaz
- Zekai Tahir Burak Women's Health Education and Research Hospital, Division of Neonatology, Ankara, Turkey
| | - Nilüfer Okur
- Zekai Tahir Burak Women's Health Education and Research Hospital, Division of Neonatology, Ankara, Turkey
| | - Dilek Dilli
- Zekai Tahir Burak Women's Health Education and Research Hospital, Division of Neonatology, Ankara, Turkey
| | - Ahmet Yeşilyurt
- Zekai Tahir Burak Women's Health Education and Research Hospital, Division of Genetics, Ankara, Turkey
| | - Şerife Suna Oğuz
- Zekai Tahir Burak Women's Health Education and Research Hospital, Division of Neonatology, Ankara, Turkey
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Karadag A, Yesilyurt A, Unal S, Keskin I, Demirin H, Uras N, Dilmen U, Tatli MM. A chromosomal-effect study of intensive phototherapy versus conventional phototherapy in newborns with jaundice. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2009; 676:17-20. [DOI: 10.1016/j.mrgentox.2009.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 02/18/2009] [Accepted: 03/05/2009] [Indexed: 01/12/2023]
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3
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Yildirim M, Ikbal M, Tos T, Seven B, Pirim I, Varoglu E. Genotoxicity of thallium-201 in patients with angina pectoris undergoing myocardial perfusion study. TOHOKU J EXP MED 2005; 206:299-304. [PMID: 15997200 DOI: 10.1620/tjem.206.299] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Thallium-201 (201Tl) has been widely used as a nuclear reagent for myocardial blood flow imaging. The purpose of this study was to investigate genotoxic effects of 201Tl in patients with angina pectoris (n = 21), who had undergone myocardial perfusion imaging. Lymphocytes were isolated from each patient before, and 3, 30 and 90 days after 201Tl administration (111 MBq, 3 mCi) and were analyzed for chromosomal aberrations, sister chromatid exchanges, mitotic index and replicative index. There were significant increases in chromosomal aberrations and sister chromatid exchanges 3 days after 201Tl administration (p < 0.001), although no difference was noted in these values after 30 and 90 days (p > 0.05). Moreover, decreased mitotic index and replicative index were noted after 3 days of 201Tl administration (p < 0.001). These results suggest that the administration of 201Tl for myocardial blood flow imaging may induce genetic damage.
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Affiliation(s)
- Mustafa Yildirim
- Department of Nuclear Medicine, Ataturk University, Medical Faculty, Erzurum, Turkey.
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Wojcik A, Bruckmann E, Obe G. Insights into the mechanisms of sister chromatid exchange formation. Cytogenet Genome Res 2004; 104:304-9. [PMID: 15162056 DOI: 10.1159/000077507] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Accepted: 12/08/2003] [Indexed: 11/19/2022] Open
Abstract
The DNA lesions responsible for the formation of sister chromatid exchanges (SCEs) have been the object of research for a long time. SCEs can be visualized by growing cells for either two rounds of replication in the presence of 5-bromo-2'-deoxyuridine (BrdU) or for one round with BrdU and the next without. If BrdU is added after cells were treated with a DNA-damaging agent, the effect on SCEs can only be analyzed in the second post-treatment mitosis. If one wishes to analyze the first post-treatment mitosis, cells unifilarily labeled with BrdU must be treated. Due to the highly reactive bromine atom, BrdU interacts with such agents like ionizing and UV radiation enhancing the frequency of SCEs. However, its precise role in this process was difficult to assess for a long time, because no alternative technique existed that allowed differential staining of chromatids. We have recently developed a method to differentially label sister chromatids with biotin-16-2'-deoxyuridine-5'-triphosphate (biotin-dUTP) circumventing the disadvantage of BrdU. This technique was applied to study the SCEs induced by ionizing and UV radiation as well as by mitomycin C, DNaseI and AluI. This article is a review of the results and conclusions of our previous studies.
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Affiliation(s)
- A Wojcik
- Institute of Nuclear Chemistry and Technology, Warszawa, Poland
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5
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Wojcik A, Opalka B, Obe G. Analysis of inversions and sister chromatid exchanges in chromosome 3 of human lymphocytes exposed to X-rays. Mutagenesis 1999; 14:633-8. [PMID: 10567039 DOI: 10.1093/mutage/14.6.633] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
It has been shown repeatedly that exposure of G(1) cells unifilarily labelled with 5-bromodeoxyuridine (BrdU) to X-rays leads to sister chromatid exchanges (SCE) when the cells are allowed to grow for one further cycle in the absence of BrdU. It has been suggested that damage induced by ionizing radiation does not lead to 'true' SCE and that the observed SCE are 'false', resulting from structural chromosomal aberrations, especially interstitial inversions. We used a painting probe for the p14 region of human chromosome 3 and anti-BrdU antibodies to analyse the frequency of radiation-induced SCE in that chromosome. This method allowed us to discriminate between para- and pericentric 'true' and 'false' SCE. Our results indicate that most radiation-induced SCE do not result from inversions.
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Affiliation(s)
- A Wojcik
- Institute of Genetics, University of Essen, FB-9, D-45171 Essen, Germany
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6
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Sönmez S, Ikbal M, Yíldírím M, Gepdiremen A, Oztaş S. Sister chromatid exchange analysis in patients exposed to low dose of iodine-131 for thyroid scintigraphy. Mutat Res 1997; 393:259-62. [PMID: 9393618 DOI: 10.1016/s1383-5718(97)00110-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To determine the genotoxic risk associated with diagnostic exposure to low doses of iodine 131 (131I), sister chromatid exchange (SCE) analysis was performed in lymphocytes of 18 non-smoking women who received 370 kBq (10 microCi) intravenous 131I sodium iodide as an adjuvant for scintigraphy for diagnosing thyroid nodularity. SCE frequencies were measured before and after 131I administration. SCE results in the pre-treated phase were regarded as control. Although SCE values 24 h after 131I administration did not show a significant increment (p > 0.05), there was a significant increase 72 h after treatment (p < 0.05). These results indicate that genetic damage might be induced by low dose of 131I.
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Affiliation(s)
- S Sönmez
- Department of Medical Genetics, Atatürk University Medical Faculty, Erzurum, Turkey.
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7
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Morales-Ramírez P, Mendiola-Cruz MT. In vivo radioprotective effect of chlorophyllin on sister chromatid exchange induction in murine spermatogonial cells. Mutat Res 1995; 344:73-8. [PMID: 7565896 DOI: 10.1016/0165-1218(95)90041-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The radioprotective capacity of chlorophyllin was determined by measuring the reduction of gamma-ray-induced sister chromatid exchange (SCE) in murine spermatogonia in vivo. The results obtained in experiments using 100 and 200 micrograms of chlorophyllin per gram of body weight (bw) and irradiated either before or after BrdU incorporation, indicate that a chlorophyllin dose of 200 micrograms/g bw protects 100% against the induction of SCE by 0.75 Gy of gamma-rays and 100 micrograms/g bw protects less than 50%. Chlorophyllin per se did not have any effect on the SCE frequency.
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Affiliation(s)
- P Morales-Ramírez
- Instituto Nacional de Investigaciones Nucleares, Mexico, D.F., Mexico
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8
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Morales-Ramírez P, Cruz-Vallejo VL, Vallarino-Kelly T, Rodríguez-Reyes R. Persistence during G1 of gamma ray- or mitomycin C-induced lesions eliciting SCE in murine salivary gland cells in vivo. SOMATIC CELL AND MOLECULAR GENETICS 1995; 21:33-41. [PMID: 7604356 DOI: 10.1007/bf02255820] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The efficiency of mitomycin C or gamma rays to induce SCE in early or late G1 was determined in synchronized murine salivary gland cells in vivo, as a measure of the capacity of this tissue to repair the lesions involved in SCE formation before S. The SCE frequencies induced by MMC in the first division (before BrdU incorporation) were significantly lower in the early G1 compared to the late G1, indicating some repair of SCE-inducing lesions. In the second division (after BrdU incorporation), there was no difference between SCE induced in early and late G1, indicating that MMC-induced lesions in such conditions are very persistent and not repairable during G1. The radio induced SCE frequency at early G1 was significantly lower than that observed in late G1, in cells irradiated after BrdU incorporation, suggesting that half of gamma ray-induced DNA lesions that elicit SCEs were repaired.
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Affiliation(s)
- P Morales-Ramírez
- Departamento de Radiobiología, Instituto Nacional de Investigaciones Nucleares, México, D.F., México
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9
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Morales-Ramírez P, García-Rodríguez MC. In vivo effect of chlorophyllin on gamma-ray-induced sister chromatid exchange in murine bone marrow cells. Mutat Res 1994; 320:329-34. [PMID: 7508558 DOI: 10.1016/0165-1218(94)90085-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The aim of the present work is to determine the radioprotective capacity of chlorophyllin, by measuring the reduction of gamma-ray-induced sister-chromatid exchange (SCE) in murine bone marrow cells in vivo. The results obtained in two separate experiments, using 10, 50 and 100 micrograms of chlorophyllin per g of body weight (bw), indicate that chlorophyllin per se did not have any effect on the SCE frequency and that the dose of 100 micrograms/g bw protects 100% against the induction of SCE by 1.0 Gy of gamma-rays; 50 micrograms/g bw protects less than 50% and 10 micrograms/g bw affords no protection.
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10
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Cortés F, Daza P, Piñero J, Escalza P. Evidence that SCEs induced by mutagens do not occur at the same locus in successive cell cycles: lack of cancellation in three-way stained CHO chromosomes. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1994; 24:203-207. [PMID: 7525277 DOI: 10.1002/em.2850240309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
An approach based on the synchronization of CHO cells after a first cell cycle incorporating a relatively low amount of bromodeoxyuridine (BrdUrd) into DNA, followed by mutagenic treatment and subsequent culture for second and third generations of BrdUrd incorporation for the scoring of sister chromatid exchanges (SCEs) per cell cycle in three-way differentially (TWD) stained chromosomes, has been used to investigate the possible cancellation of SCEs. Cancellation is expected to occur if two mutagen-induced SCEs occur at exactly the same site in subsequent rounds of replication. Lesions in DNA seem to persist and are able to induce SCE throughout two cell cycles after treatment with the three mutagens tested--mitomycin C (MMC), ethyl methanesulfonate (EMS) and ultraviolet (UV) light--though this latter agent was shown as only moderately persistent. Our results seem to indicate that SCEs induced by these mutagens do not take place at the same locus in successive cell generations, as assessed by a lack of SCE cancellation.
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Affiliation(s)
- F Cortés
- Department of Cell Biology, Faculty of Biology of Seville, Spain
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11
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Morales-Ramírez P, Mendiola-Cruz MT, Vallarino-Kelly T, Rodríguez-Reyes R. Comparison of sister chromatid exchange induction in murine germinal and somatic cells by gamma radiation exposure in vivo. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1994; 24:89-95. [PMID: 7925331 DOI: 10.1002/em.2850240203] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Sister chromatid exchange (SCE) induction by gamma rays was determined in spermatogonia irradiated before or after BrdU incorporation. Furthermore, the comparison of responses obtained in spermatogonia, bone marrow and salivary gland cells was carried out in the cells irradiated after BrdU incorporation, a condition which permits a higher SCE induction. Results indicate that gamma ray exposure of spermatogonia could induce a significant increase in SCE frequency with doses as low as 0.27 Gy, either before or after BrdU incorporation. However, the increase caused by radiation exposure after BrdU incorporation in spermatogonia was nearly three times lower than that obtained in both bone marrow and salivary gland cells. These data suggest that spermatogonia are either more efficient in repairing the gamma ray-induced lesions involved in SCE production or that these cells are less prone to the induction of such lesions.
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Affiliation(s)
- P Morales-Ramírez
- Instituto Nacional de Investigaciones Nucleares, Lomas Barrilaco, México, D.F., Mexico
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12
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Cortés F, Escalza P. Three-Way Differential Staining of Chromosomes for the Identification of SCEs per Cell Cycle: Fundamentals and Applications. ADVANCES IN MUTAGENESIS RESEARCH 1993. [DOI: 10.1007/978-3-642-77466-9_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
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13
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Brandom WF, McGavran L, Bistline RW, Bloom AD. Sister chromatid exchanges and chromosome aberration frequencies in plutonium workers. Int J Radiat Biol 1990; 58:195-207. [PMID: 1973437 DOI: 10.1080/09553009014551551] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Peripheral blood lymphocytes from controls and from a small population of plutonium workers with internal plutonium depositions, cumulative chronic external irradiation, and occupational exposure to single or multiple chemicals, were analysed for the frequency of sister chromatid exchanges (SCE) and chromosome aberrations. SCE are sensitive to some chemical mutagens, while chromosome aberrations are induced by moderate to high doses of ionizing radiation, and therefore these different cytogenetic end-points are complementary. We analysed the frequency data from workers grouped by internal systemic burdens of plutonium (less than 148, 148-740 and greater than 740 Bq) and to those exposed to five chemicals in the workplace: perchloroethylene, beryllium, carbon tetrachloride, benzene, and trichloroethylene. A significant increase in chromosome aberrations compared with the control frequency was observed only in cells of workers with greater than 740 Bq of internalized plutonium. Based on prior studies, the lack of a dose-response indicator from internal plutonium was not unexpected because of the small sample and the low frequency of aberrations induced at the lower plutonium burdens. There were no significant increases in the SCE mean frequencies when analysed by estimated internal plutonium or from exposure to any of the chemicals.
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Courtois YA, Min S, Lachenal C, Jacquot-Deschamps JM, Callais F, Festy B. Genotoxicity of organic extracts from atmospheric particles. Ann N Y Acad Sci 1988; 534:724-40. [PMID: 3389685 DOI: 10.1111/j.1749-6632.1988.tb30162.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Experiments to evaluate the genotoxic potentialities of urban air particles sampled in Paris (France) after organic solvent extraction have been carried out using four in vitro genotoxicity tests. The two bacterial tests (the Ames test and the SOS Chromotest) demonstrate the genotoxicity of the organic extracts of atmospheric particles; two additional tests (induction of 6-thioguanine mutants and sister chromatid exchanges), carried out on V79 Chinese hamster cells, also confirm these potentialities. These results show clearly that particulate organic extracts induce point mutations in both bacteria and mammalian cells, or the cellular response (SOS repair) to these mutations in bacteria; likewise, they are responsible for clastogenic effects in mammalian cells. Genotoxicity is due either to direct genotoxic chemicals or to active metabolic products of the action of microsomal enzymes. The optimalization of testing procedures is discussed in order to appreciate the contribution of genotoxicity tests to the study of atmospheric pollution.
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Affiliation(s)
- Y A Courtois
- Laboratoire d'Hygiène de la Ville de Paris, France
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15
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Venegas W, Lasne C, Lowy R, Buisson JP, Chouroulinkov I. Naphthofurans induced chromosomal aberrations detected in metaphase, anaphase and telophase V79 Chinese hamster cells. Mutat Res 1985; 157:53-62. [PMID: 4010697 DOI: 10.1016/0165-1218(85)90049-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The mutagenic activities of 5 newly synthesized naphthofurans were analysed in two in vitro cytogenetic assays: the metaphase chromosomal aberration assay and the anaphase telophase bridge-fragment assay. Both assays were conducted using V79 Chinese hamster cells. The compounds included: 2-nitro-7-methoxynaphtho[2,1-b]furan (A), 2-nitro-8-methoxynaphtho[2,1-b]furan (B), 2-nitro-naphtho[2,1-b]furan (C), 2-nitro-7-bromonaphtho[2,1-b]furan (D) and 7-methoxynaphtho[2,1-b]furan (E). The cells were treated with 3 concentrations (0.1, 0.2 and 0.4 microgram/ml) of each compound, in the dose range already tested in studies on the mutagenic properties of the same compounds realised with other systems. The highest concentration, only, was used in the anaphase-telophase assay. In the first approach, compounds A, B and C were active while compounds D and E did not increase significantly the aberration frequency above that of the DMSO controls. The results were confirmed in the second approach. They demonstrated that the two studies were complementary. Based on their genotoxic activities, the 5 compounds were ranked in the following decreasing order of potency: A congruent to B much greater than C greater than D congruent to E congruent to DMSO; which is comparable to the ranking order obtained in different in vitro mutagenic and carcinogenic assays. All these activities are closely related to the highly specific molecular structure of each compound, particularly to the nature and position of the different substituents introduced on the skeleton.
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Schvartzman JB, Goyanes VJ, Campos A, Lage AM, Veiras C, Silva MC, Ramos S. Persistence of DNA lesions and the cytological cancellation of sister chromatid exchanges. Chromosoma 1985; 92:7-10. [PMID: 3924528 DOI: 10.1007/bf00327239] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The ability of UV light, mitomycin C and ionizing radiation to induce the formation of sister chromatid exchanges (SCEs) at the same locus in successive cell generations was investigated in human lymphocytes. Cells were exposed to the DNA damaging agents after they had completed their first round of DNA replication, and SCEs were examined at the third division in chromosomes that had been differentially stained three ways. Although some of these treatments induced long-lived lesions that increased the frequency of SCEs in successive cell generations, none of the lesions led to the formation of consecutive SCEs at the same locus in successive cell generations. This observation seriously challenges the hypothesis that SCE cancellation results as a consequence of persistence of the lesions induced by these agents.
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Kaina B, Aurich O. Dependency of the yield of sister-chromatid exchanges induced by alkylating agents on fixation time. Possible involvement of secondary lesions in sister-chromatid exchange induction. Mutat Res 1985; 149:451-61. [PMID: 3990696 DOI: 10.1016/0027-5107(85)90163-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Chinese hamster V79 cells were pulse-treated (for 60 min) with various mutagens three, two or one cell cycles before fixation (treatment variants A, B and C, respectively) and the frequencies of induced SCEs were analysed and compared. The degree of increase in frequency of SCEs with dose in the treatment variants depended on the mutagen used. For the methylating agents MNU, MNNG and DMPNU, high yields of SCEs were obtained in the treatment variants A and B, and there was no difference in the efficiency with which these agents induced SCEs in these treatment variants. In the treatment variant C, however, no SCEs were induced with mutagen doses yielding a linear increase in SCE frequency in treatment variants A and B. A slight increase in SCE frequency in treatment variant C was observed only when relatively high doses of MNU or MNNG were applied. Like the above agents, EMS, ENU and MMS induced more SCEs in treatment variants A and B than in C, but for these agents treatment variant B was most effective and SCEs were induced over the entire dose range, also in treatment variant C. As opposed to the methylating and ethylating agents, MMC induced SCEs with high efficiency when treatment occurred one or two generations prior to fixation. There was no difference in SCE frequency between these treatment variants. MMC was completely ineffective for the induction of SCEs when treatment occurred three generations before fixation. The unexpectedly low SCE frequencies induced by the methylating and ethylating agents when treatment occurred one generation before fixation were not due to the exposure of cells to BrdU prior to mutagen treatment. From the results obtained, it is concluded that DNA methylation and ethylation lesions give rise to SCEs only with very low probability during the replication cycle after the lesion's induction, and that subsequent lesions produced during or after replication of the methylated or ethylated template (secondary lesions) are of prime importance for SCE formation after alkylation. For MMC, however, primary lesions seem to be most important for SCE induction.
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Lasne C, Gu ZW, Venegas W, Chouroulinkov I. The in vitro micronucleus assay for detection of cytogenetic effects induced by mutagen-carcinogens: comparison with the in vitro sister-chromatid exchange assay. Mutat Res 1984; 130:273-82. [PMID: 6749166 DOI: 10.1016/0165-1161(84)90103-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The sensitivity of a cytogenetic assay, as expressed by the in vitro induction of micronuclei (MN), was compared to the in vitro induction of sister-chromatid exchanges (SCEs). Chinese hamster lung (V79) cells were exposed to 3 known alkylating agents: methyl methanesulphonate (MMS), ethyl methanesulphonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and to 5 newly synthesized naphthofurans: 2-nitro-7-methoxynaphtho[2,1-b]furan (A), 2-nitro-8-methoxynaphtho[2,1-b]furan (B), 2-nitronaphtho[2,1-b]furan (C), 2-nitro-7-bromonaphtho[2,1-b]furan (D) and 7-methoxynaphtho[2,1-b]furan (E). The induction of MN only was also analysed after exposure of the cells to 4 alcohols: ethanol, methanol, butanol and propanol. The lowest dose at which a significant effect could be observed was determined. In both assays, MNNG, MMS and EMS were equally active with the following order of potency: MNNG greater than MMS greater than EMS, the latter being a very weak inducer of MN and SCE. Compounds A and B were also very effective in both assays. Compound C was a more active inducer of SCE than MN. Compounds D and E were not active in either assay. None of the 4 alcohols induced MN. Our results are compared with the previously published data on in vitro and in vivo induction of SCE and MN. We conclude that the MN in vitro assay which detects clastogens as well as agents affecting the spindle apparatus, is a good indicator of genotoxicity, though slightly less sensitive than the in vitro SCE test. It could provide a rapid, simple and inexpensive complementary short-term test for the evaluation of potentially mutagenic chemicals.
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Ikushima T, Benz RD, Carsten AL. Sister chromatid exchanges in bone marrow cells of mice maintained on tritiated water. INTERNATIONAL JOURNAL OF RADIATION BIOLOGY AND RELATED STUDIES IN PHYSICS, CHEMISTRY, AND MEDICINE 1984; 45:251-6. [PMID: 6609138 DOI: 10.1080/09553008414550351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The ability of tritium to induce sister chromatid exchanges (SCEs) has been investigated in male mice of the Hale-Stoner-Brookhaven strain maintained on drinking water containing 3.0 microCi/ml tritiated water (HTO). At selected intervals after 28-261 days of consuming HTO, the frequency of SCEs and the kinetics of cellular proliferation were measured in bone marrow cells of animals maintained on HTO, and in age-matched control groups, by 5-bromo-2'-deoxyuridine labelling methods. A statistically significant (1 percent level) elevation of SCEs was observed after 81, 163, 192, 247 and 261 days of HTO ingestion. The frequency of induced SCEs increased linearly with the ingestion time. These results are of particular interest since ionizing radiation is generally not considered to be an efficient inducer of SCEs.
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Gentil A, Renault G, Kinsella A. Induction of sister chromatid exchanges in split-dose and cell-fusion experiments. BASIC LIFE SCIENCES 1984; 29 Pt A:141-148. [PMID: 6532416 DOI: 10.1007/978-1-4684-4889-4_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Schvartzman JB, Goyanes VJ, Tice RR. DNA damage persistence and site specificity in SCE formation. BASIC LIFE SCIENCES 1984; 29 Pt A:215-27. [PMID: 6085259 DOI: 10.1007/978-1-4684-4889-4_17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Morales-Ramírez P, Vallarino-Kelly T, Rodríguez-Reyes R. In vivo persistence of sister chromatid exchanges (SCE) induced by gamma rays in mouse bone marrow cells. ENVIRONMENTAL MUTAGENESIS 1984; 6:529-37. [PMID: 6468347 DOI: 10.1002/em.2860060406] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The sister chromatid exchange (SCE) frequencies induced in bone marrow cells by in vivo irradiation with gamma rays before or after bromodeoxyuridine (BrdUrd) incorporation were compared. The frequency of SCE at different postirradiation times was also measured in bone marrow cells in vivo, irradiated before BrdUrd incorporation. Increased sensitivity to SCE induction by radiation was found in cells after BrdUrd incorporation for one cycle when compared with cells irradiated before BrdUrd incorporation. The increased SCE frequency persisted for at least 72 hr after the initial irradiation, implying that the gamma ray-induced lesion(s) capable of eliciting an SCE are persistent and cannot be easily repaired.
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