Radiation-induced chromosome aberrations in bone marrow cells leading to acute myeloid leukemia in mouse

International Nuclear Information System (INIS)

Nobuhiko Ban; Tomoko Kusama

1996-01-01

It is well known that radiation-induced acute myeloid leukemia (RI-AML) in mice is charaterized by deletion and/or rearrangement of chromosome 2. While chromosome 2 has been suspected to be a target of RI-AML, radiation-sensitive site of the chromosome might be implicated in the leukemogenesis. There were few cytogenetical studies, however, focusing on chromosomal rearrangements shortly after irradiation, and little was known about the frequency and pattern of chromosome 2 aberrations during the early period. In this study, metaphase samples were prepared from whole-body irradiated mice 24 hours after irradiation, most of the cells considered to be in the first mitotic stage. Distribution of chromosomal breakpoints on the metaphase samples were analyzed to study the relationship between chromosome aberrations and RI-AML. (author)

Dose-response relationship for chromosomal aberrations induced in human lymphocytes by 18 MeV electron beam irradiation

International Nuclear Information System (INIS)

Lashin, E.A.; Elaasar, E.M.; Moustafa, H.F.; Bakir, Y.Y.; Al Zenki, S.D.

1990-01-01

Dose response curves for lymphocyte chromosome aberration frequencies using X- and gamma radiation became an important and reliable indicator as biological dosimeter especially in radiation accidents and occupational over exposures. Nowadays electron beam therapy is frequently used for their advantages in cases of tumours under or near to the body surface. Dose-response curves for these electron beams are rarely published. Human peripheral blood lymphocytes were in vitro irradiated with various low and high doses (0.1 Gy to 4.9 Gy) of 18 MeV electron beams to utilize such a dose-response curve using chromosomal aberration frequencies as a biological indicator. Then we compared the biological curve with physically obtained curves normally used in planning for radiotherapy treatment. It is interesting to find a significant difference between both of them. The biological curve is generally higher in value and the aberrations induced by 93% of a dose is significantly higher and deeper in site than those aberrations induced by the 100% dose calculated physically. If the above observation is confirmed by detailed studies, it would be of importance to the radiotherapist to plan for isodose curves according to biological determinations. (author)

Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

International Nuclear Information System (INIS)

Monobe, Manami

2002-01-01

We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/μm carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (P<0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (P<0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbon-ion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation. (author)

Radiation-induced cellular reproductive death and chromosome aberrations

International Nuclear Information System (INIS)

Bedford, J.S.; Mitchell, J.B.; Griggs, H.G.; Bender, M.A.

1978-01-01

If a major mode of cell killing by ionizing radiation is the death of cells containing visible chromosomal aberrations, as for example from anaphase-bridge formation at mitosis, then cells bearing such aberrations should be selectively eliminated from the population, resulting in an increased survival potential for the population remaining at each succeeding cell generation. Using synchronized V79B Chinese hamster cells, we measured the aberration frequency and the colony-forming ability of mitotic cells at each of the first three generations following irradiation in G1. Cells were resynchronized by mechanial harvest at each succeeding mitosis after irradiation in order to avoid mixing of generations in the cell population at later sampling times. As anticipated, the chromosome aberration frequencies decreased markedly from the first to the second and from the second to the third mitosis. The surviving fraction, however, was virtually the same for plating assays carried out immediately after irradiation, at the first, or at the second mitosis. The surviving fraction was significantly higher for cells reaching the third postirradiation mitosis. Survival and aberration frequencies were assayed again at approximately the fourteenth postirradiation division, by which time the irradiated and control populations were not significantly different

DNA damage and chromosome aberration induced by heavy-ion beams

International Nuclear Information System (INIS)

Takakura, Kahoru; Funada, Aya; Aoki, Mizuho; Furusawa, Yoshiya

2003-01-01

The aim of this study is to clarify the relation between cell death and chromosomal aberration in cultured human cells (human salivary gland (HSG) tumor cells and GM05389 human normal fibroblasts) irradiated with heavy ion beams on the basis of linear energy transfer (LET) values. The LET dependences of cell death were observed for the both cells by the method of colony assay. The LET dependences of the chromosomal aberrations, breaks and gaps, isochromatid breaks and exchanges were also observed for the both cells using the premature chromosome condensation (PCC) method. From these results it is suggested that exchange formation is essential for the cell death caused by heavy ion beam irradiation. It is suspected that the densely ionizing track structure of hight LET heavy ions inhibits the effective repair in the chromatid breaks and isochromatid breaks and finally induce much exchange in the cells, which should be essential cause of cell death. (author)

Chromosome aberrations and cell survival in irradiated mammalian cells

International Nuclear Information System (INIS)

Tremp, J.

1981-01-01

A possible correlation between chromosome aberrations and reduced proliferation capacity or cell death was investigated. Synchronized Chinese hamster fibroblast cells were irradiated with 300 rad of x rays in early G 1 . Despite synchronization the cells reached the subsequent mitosis at different times. The frequency of chromosome aberrations was determined in the postirradiation division at 2-h intervals. The highest frequency occurred in cells with a first cell cycle of medium length. The colony-forming ability of mitotic cells was measured in parallel samples by following the progress of individual mitoses. The proportion of cells forming macrocolonies decreased with increasing cell cycle length, and the number of non-colony-forming cells increased. Irrespective of various first cell cycle lengths and different frequencies of chromosome aberrations, the number of cells forming microcolonies remained constant. A correlation was found between the absence of chromosome aberrations and the ability of cells to form macrocolonies. However, cells with a long first cell cycle formed fewer macrocolonies than expected

Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

Science.gov (United States)

Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

2011-01-01

Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

Chromosomal geometry in the interface from the frequency of the radiation induced chromosome aberrations

International Nuclear Information System (INIS)

Nasazzi, N.; Otero, D.; Di Giorgio, M.

1996-01-01

Ionizing radiation induces DNA double-strand breaks (DSBs) and their interaction and illegitimate recombination produces chromosomal aberrations. Stable chromosomal aberrations comprise inter-chromosomal events (translocations) and intra-chromosomal events (inversions). When DSBs induction and interaction is done at random, and the proximity effects are neglected, the expected relation between translocations and inversions is F=86, based on chromosome arm length. The number of translocations and inversions is analyzed by using G-banding in 16 lymphocytes cultures from blood samples acutely irradiated with γ-rays (dose range: 0,5 Gy - 3 Gy). The result obtained was: F=13,5, significantly smaller than F=86. Literature data show similar small F values, but strongly spread. The excess of inversions could be explained by a 'proximity effect', it means that more proximate DSBs have more interaction probability. Therefore, it is possible to postulate a special chromosome arrangement during irradiation and the subsequent interval. We propose a model where individual chromosomes show spherical confinement with some degree of overlapping and DSBs induction proportional to cross section. A DSBs interaction probability function with cut-off length= 1μ is assumed. According to our results, the confinement volume is ≅ 6.4% of the nuclear volume. Nevertheless, we presume that large spread in F data could be due to temporal variation in overlapping and spatial chromosomal confinement. (authors). 14 refs

Inter-chromosomal heterogeneity in the formation of radiation induced chromosomal aberrations

International Nuclear Information System (INIS)

Natarajan, A.T.; Vermeulen, S.; Boei, J.J.W.A.

1997-01-01

It is generally assumed that radiation induced chromosomal lesions are distributed randomly and repaired randomly among the genome. Recent studies using fluorescent in situ hybridization (FISH) and chromosome specific DNA libraries indicate that some chromosomes are more sensitive for radiation induced aberration formation than others. Chromosome No. 4 in human and chromosome No. 8 in Chinese hamster have been found to involve more in exchange aberrations than others, when calculated on the basis of their DNA content. Painting with arm specific chromosome libraries indicate that the frequencies of radiation induced intra-chromosome exchanges (i.e., between the arms of a chromosome, such as centric rings and inversions) are far in excess than one would expect on the basis of the frequencies of observed inter-chromosomal exchanges. The possible factors leading to the observed heterogeneity will be discussed

Types of structural chromosome aberrations and their incidences in human spermatozoa X-irradiated in vitro

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Kamiguchi, Yujiroh; Tateno, Hiroyuki; Mikamo, Kazuya (Asahikawa Medical College (Japan). Department of Biological Sciences)

1990-02-01

The authors studied the effects of in vitro X-irradiation on human sperm chromosomes, using our interspecific in vitro fertilization system between human spermatozoa and zona-free hamster oocytes. 28 semen samples from 5 healthy men were exposed to 0.23, 0.45, 0.91 and 1.82 Gy of X-rays. Totals of 2098 and 2862 spermatozoa were karyotyped in the control and the irradiated groups, respectively. The indicence of spermatozoa with X-ray-induced structural chromosome aberrations (Y) increased linearly with increasing dosage (D), being best expressed by the equation, Y = 0.08 + 34.52 D. The incidence of breakage-type aberrations was moe than 9 times higher than that of exchange-type aberrations. Both of them showed linear dose-dependent increases, which were expressed by the regression lines, Y = -0.014 + 0.478 D and Y -0.010 + 0.057 D, respectively. The incidence of chromosome-ltype aberrations was about 6 times higher than that of chromatid-type aberrations. Their dose-dependent increases were expressed by the regression lines, Y = -0.015 + 0.462 D and Y = -0.006 + 0.079 D, respectively. These results are discussed in relation to the previous data obtained with {gamma}-rays. The repair mechanism of X-ray-induced sperm DNA lesions is also discussed. (author). 21 refs.; 4 figs.; 4 tabs.

Study of radiation-induced chromosomal aberrations

International Nuclear Information System (INIS)

Wolfring, E.

2004-06-01

A method for determining chromosomal aberrations was established for the purpose of examining the relative biological effectiveness (RBE) of photon radiation with respect to mammary epithelium cells. Cells were exposed to 25 kV X-radiation and to 200 kV X-radiation for comparison and the resulting concentrations of chromosomal aberrations were compared. The RBE M value for radiation-induced fragmentation was found to be 4.2 ± 2.4, while the RBE M value for radiation-induced generation of dicentric chromosomes was found to be 0.5 ± 0.5. In addition to the evaluation of chromosomal aberrations the number of cell cycles undergone by the cells was monitored by means of BrDU staining. As expected, the proportion of cells which underwent more than one cell cycle following exposure to 5 Gy was very low in both cases, amounting to 1.9% (25 kV) and 3.2 (200 kV). Non-radiated cells yielded control values of 26.0% and 12.6%, suggesting variations in external conditions from day to day

Influence of DMSO on Carbon K ultrasoft X-rays induced chromosome aberrations in V79 Chinese hamster cells

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Natarajan, Adayapalam T., E-mail: natarajan@live.nl [University of Tuscia, Viterbo (Italy); Palitti, Fabrizio [University of Tuscia, Viterbo (Italy); Hill, Mark A. [CRUK/MRC Gray Institute for Radiation Oncology and Biology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ (United Kingdom); MRC Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD (United Kingdom); Stevens, David L. [MRC Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD (United Kingdom); Ahnstroem, Gunnar [Department of Microbiology and Genetic Toxicology, Stockholm University, Stockholm (Sweden)

2010-09-10

Ultrasoft X-rays have been shown to be very efficient in inducing chromosomal aberrations in mammalian cells. The present study was aimed to evaluate the modifying effects of DMSO (a potent scavenger of free radicals) on the frequencies of chromosome aberrations induced by soft X-rays. Confluent held G1 Chinese hamster cells (V79) were irradiated with Carbon K ultrasoft X-rays in the presence and absence of 1 M DMSO and frequencies of chromosome aberrations in the first division cells were determined. DMSO reduced the frequencies of exchange types of aberrations (dicentrics and centric rings) by a factor of 2.1-3.5. The results indicate that free radicals induced by ultrasoft X-rays contribute to a great extent to the induction of chromosome aberrations. The possible implications of these results in interpreting the mechanisms involved in the high efficiency of ultrasoft X-rays in the induction of chromosome aberrations are discussed.

Persistence of radiation-induced chromosome aberrations in a long-term cell culture.

Science.gov (United States)

Duran, Assumpta; Barquinero, Joan Francesc; Caballín, María Rosa; Ribas, Montserrat; Barrios, Leonardo

2009-04-01

The aim of the present study was to evaluate the persistence of chromosome aberrations induced by X rays. FISH painting and mFISH techniques were applied to long-term cultures of irradiated cells. With painting, at 2 Gy the frequency of apparently simple translocations remained almost invariable during all the culture, whereas at 4 Gy a rapid decline was observed between the first and the second samples, followed by a slight decrease until the end of the culture. Apparently simple dicentrics and complex aberrations disappeared after the first sample at 2 and 4 Gy. By mFISH, at 2 Gy the frequency of complete plus one-way translocations remained invariable between the first and last sample, but at 4 Gy a 60% decline was observed. True incomplete simple translocations disappeared at 2 and 4 Gy, indicating that incompleteness could be a factor to consider when the persistence of translocations is analyzed. The analysis by mFISH showed that the frequency of complex aberrations and their complexity increased with dose and tended to disappear in the last sample. Our results indicate that the influence of dose on the decrease in the frequency of simple translocations with time postirradiation cannot be fully explained by the disappearance of true incomplete translocations and complex aberrations. The chromosome involvement was random for radiation-induced exchange aberrations and non-random for total aberrations. Chromosome 7 showed the highest deviations from expected, being less and more involved than expected in the first and last samples, respectively. Some preferential chromosome-chromosome associations were observed, including a coincidence with a cluster from radiogenic chromosome aberrations described in other studies.

Structural analysis of radiation-induced chromosome aberrations by atomic force microscope (AFM) before and after Giemsa staining

International Nuclear Information System (INIS)

Murakami, M.; Kanda, R.; Minamihisamatsu, M.; Hayata, I.

2003-01-01

Full text: We have studied structures of chromosome aberration induced by ionizing radiation by an atomic force microscope (AFM). The AFM could visualize the fine structure of chromosomes on Giemsa stained or unstained samples, although it was difficult to visualize unstained chromosomes by light microscope. The height data of chromosomes obtained by AFM provided useful information to describe detailed structure of chromatid gaps induced by heavy ion irradiation. A fibrous structure was observed on the unstained chromosome and these structures were considered to be the 30nm fibers on the chromosome. These types of structures were observed in the gaps as well as on surface of the chromosome. Further more, other types of chromosome aberration induced by ionizing radiation visualized by AFM will be presented

Chromosome Aberrations Induced in Human Peripheral Blood by 2-MeV X-Irradiation to the Whole Body and In Vitro

Energy Technology Data Exchange (ETDEWEB)

Buckton, Karin E.; Langlands, A. O.; Smith, P. G.; Looby, P. C.; Woodcock, G. E. [Medical Research Council, Clinical and Population Cytogenetics Research Unit, Western General Hospital Edinburgh (United Kingdom); McLelland, J. [Edinburgh Royal Infirmary and Western General Hospital, Edinburgh (United Kingdom)

1969-11-15

In recent years it has proved possible to correlate the incidence of ring and dicentric chromosomes in cultured human peripheral blood lymphocytes with given radiation doses both in vitro and following partial or whole body irradiation exposure in vivo In the present study a comparison is made between the yield of aberrations in six men with advanced cancer who received whole body irradiation in doses varying between 36 and 50 rads and the yield of aberrations in samples of their blood drawn before exposure and irradiated in vitro simultaneously to the same dose A comparison is also made between the yield of aberrations following in vitro irradiation to much higher doses of blood derived from these same cancer patients and blood from non cancer controls The significance of these findings is discussed with reference to biological dosimetry using chromosome aberrations as the parameter for both external and internal irradiation Apart from such a practical application it also appears possible to develop this technique to study the sensitivity of cells to chromosome breakage by radiation in selected populations such as mongols or persons with Fancom s anaemia where there is a higher than normal incidence of malignant disease. (author)

Chromosomal aberrations induced by low-dose γ-irradiation: Study of R-banded chromosomes of human lymphocytes

International Nuclear Information System (INIS)

Al-Achkar, W.; Lefrancois, D.; Aurias, A.

1991-01-01

The effect of low-dose (0-0.5 Gy) γ-radiations was studied on R-banded chromosomes from lymphocytes of healthy donors of various ages. In cells from newborns, an increase of chromosome damage roughly proportional to the dose was found. In lymphocytes from young adults chromosomal aberrations were not detected at doses of 0.05 and 0.1 Gy, and in lymphocytes from old adults not even at 0.2 Gy. The difficulty in detecting aberrations in lymphocytes from adults is largely due to a considerable background of chromosomal anomalies which should be borne in mind in dosimetry studies. The rate of induction largely depends on the types of rearrangements. One-break terminal deletions are efficiently induced at 0.1 and 0.2 Gy and are the best indicators of exposure at these doses. At 0.5 Gy, the frequencies of 2-break lesions, i.e., dicentrics and reciprocal translocations, increase, whereas the of deletions decreases. (author). 6 refs., 3 figs., 2 tabs

Analysis of structural and numerical chromosomal aberrations at the first and second mitosis after X irradiation of two-cell mouse embryos

International Nuclear Information System (INIS)

Weissenborn, U.; Streffer, C.

1989-01-01

Two-cell mouse embryos were X-irradiated in the late G2 phase in vivo. The first and second postradiation mitoses were analyzed for chromosomal anomalies. The majority of structural aberrations visible at the first mitosis after irradiation were chromatid breaks and chromatid gaps; only a few interchanges and dicentrics were observed. The aberration frequency resulted in a dose-effect relationship which was well described by a linear model. At the second mitosis 29% of the structural aberrations of the first mitosis were counted; the aberration quality changed only slightly. It is discussed whether these aberrations are to be considered new, derived, or unchanged transmitted aberrations. Contrary to the results obtained after irradiation of one-cell embryos, little chromosome loss was induced by radiation in two-cell embryos

Failure of irradiated beef and ham to induce genetic aberrations of Drosophila

International Nuclear Information System (INIS)

Mittler, S.

1979-01-01

Ham that had been irradiated by electrons and beef which had been exposed to gamma rays from 60 Co were fed to Drosophila melanogaster to determine whether meat sterilized by these methods would induce genetic aberrations. The results showed that for yB/sc 8 y + Y males, fed on irradiated ham or beef, thermally preserved beef or frozen beef for their entire larval life, there was no significant increase in the loss of X or Y chromosomes or non-disjunction of these chromosomes; there was also no significant increase in any of the broods. Similarly for the Oregon R males, there was no significant increase in yield of sex-linked recessive lethals. Thus feeding of irradiated ham and beef to Drosophila males did not induce significant increases in genetic aberrations. The present findings are discussed in relation to the conflicting results of previous studies. (U.K.)

Effect of caffeine posttreatment on X-ray-induced chromosomal aberrations in human blood lymphocytes in vitro

Energy Technology Data Exchange (ETDEWEB)

Natarajan, A T [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Cohen (J.A.) Inst. voor Radiopathologie en Stralenbescherming, Leiden (Netherlands)); Obe, G [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Cohen (J.A.) Inst. voor Radiopathologie en Stralenbescherming, Leiden (Netherlands); Freie Univ. Berlin (Germany, F.R.). Inst. fuer Genetik); Dulout, F N [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Instituto Multidisciplinario de Biologia Celular, La Plata (Argentinia))

1980-01-01

The potentiating effect of caffeine on X-ray-induced chromosomal aberrations in human blood lymphocytes has been investigated, with special reference to cell cycle stages (G0 and G2). Both quantitative and qualitative differences in the yield of chromosomal aberrations were detected in caffeine-posttreated cells, depending on the cell stage irradiated. The studies on caffeine potentiating effects on X-irradiated G0 lymphocytes from normal adults, newborns, Down syndrome patients, and an ataxia telangiectasia patient pointed to interindividual variations in the response to caffeine potentiation among normal probands and a very profound effect in ataxia cells.

Suppressing effect of antimutagenic flavorings on chromosome aberrations induced by UV-light or X-rays in cultured Chinese hamster cells

International Nuclear Information System (INIS)

Sasaki, Yu.F.; Imanishi, Hisako; Watanabe, Mie; Ohta, Toshihiro; Shirasu

1990-01-01

Chromosome aberrations induces by UV-light or X-rays were suppressed by the post-treatment with antimutagenic flavorings, such as anisaldehyde, cinnamaldehyde, coumarin, and vanillin. UV- or X-ray-irradiated surviving cells increased in the presence of each flavouring. X-ray-induced breakage-type and exchange-type chromosome aberrations were suppressed by the vanillin treatment in the G 1 phase of the cell cycle and a greater decrease in the number of X-ray-induced chromosome aberrations during G 1 holding was observed in the presence of vanillin. Furthermore, a greater decrease in the number of X-ray-induced DNA single-strand breaks was observed in the presence of vanillin. Treatment with vanillin in the G 2 phase suppressed UV-and X-ray-induced breakage-type but not exchange-type chromosome aberrations. The suppression of breakage-type aberrations was assumed to be due to a modification of the capability of the post-replicational repair of DNA double-strand breaks. (author). 28 refs.; 5 figs.; 6 tabs

A high frequency of induction of chromosome aberrations in the bone marrow cells of LEC strain rats by X-irradiation

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Okui, Toyo (Hokkaido Inst. of Public Health, Sapporo (Japan)); Hayashi, Masanobu; Watanabe, Tomomasa; Namioka, Shigeo (Dept. of Lab. Animal Science, Hokkaido Univ., Sapporo (Japan)); Endoh, Daiji; Sato, Fumiaki (Dept. of Radiation Biology, Faculty of Veterinary Medicine, Hokkaido Univ., Sapporo (Japan)); Kasai, Noriyuki (Inst. for Animal Experimentation, Hokkaido Univ., Sapporo (Japan))

1994-08-01

LEC strain rats, which have been known to develop hereditarily spontaneous fulminant hepatitis 4 to 5 months after birth, are highly sensitive to whole-body X-irradiation when compared to WKAH strain rats. The present results showed that the frequencies of all types of chromosome aberrations induced by X-irradiation in the bone marrow cells of LEC rats were approximately 2- to 3-fold higher than those of WKAH rats, though no significant difference was observed in the frequency of spontaneous chromosome aberrations between LEC and WKAH rats.

Delayed cell death, giant cell formation and chromosome instability induced by X-irradiation in human embryo cells

International Nuclear Information System (INIS)

Roy, K.; Kodama, Seiji; Suzuki, Keiji; Watanabe, Masami

1999-01-01

We studied X-ray-induced delayed cell death, delayed giant cell formation and delayed chromosome aberrations in normal human embryo cells to explore the relationship between initial radiation damage and delayed effect appeared at 14 to 55 population doubling numbers (PDNs) after X-irradiation. The delayed effect was induced in the progeny of X-ray survivors in a dose-dependent manner and recovered with increasing PDNs after X-irradiation. Delayed plating for 24 h post-irradiation reduced both acute and delayed lethal damage, suggesting that potentially lethal damage repair (PLDR) can be effective for relieving the delayed cell death. The chromosome analysis revealed that most of the dicentrics (more than 90%) observed in the progeny of X-ray survivors were not accompanied with fragments, in contrast with those observed in the first mitosis after X-irradiation. The present results indicate that the potentiality of genetic instability is determined during the repair process of initial radiation damage and suggest that the mechanism for formation of delayed chromosome aberrations by radiation might be different from that of direct radiation-induced chromosome aberrations. (author)

Radioprotective effect of penicillin on the x-ray induced chromosome aberrations in the Syrian hamster

International Nuclear Information System (INIS)

Dey, S.K.; Manna, G.K.

1981-01-01

The frequency of chromosome aberrations in the bone marrow cells of Syrian hamsters treated with penicillin and X-rays separately and conjointly was found to be 27% in X-irradiated series, 6.3% in penicillin treated series while it was 7.6%, 8% and 6.3% respectively for the treatment of penicillin prior to, almost simultaneously with and after X-irradiation. The results indicated the protective action of penicillin on the frequency of radiation-induced chromosome damages. (author)

Effect of aspirin on chromosome aberration and DNA damage induced by X-rays in mice

Science.gov (United States)

Niikawa, M.; Chuuriki, K.; Shibuya, K.; Seo, M.; Nagase, H.

In order to reveal the anticlastogenic potency of aspirin, we evaluated the suppressive ability of aspirin on chromosome aberrations induced by X-ray. Aspirin at doses of 0.5, 5 and 50 mg/kg was administrated intraperitoneally or orally at 0.5 h after or before the X-ray irradiation. The anticlastogenic activity of aspirin on chromosome aberrations induced by X-ray was determined in the mouse micronucleus test and alkaline single cell gel electrophoresis (SCG) assay in vivo. The frequency by polychromatic erythrocytes with micronuclei (MNPCEs) was decreased by about 19-61% at 0.5 h after and about 23-62% at 0.5 h before the X-ray irradiation. DNA damage by X-ray was significantly decreased by oral administration of aspirin at 0.5 h after or before the X-ray irradiation for the SCG assay. We consider aspirin can be used as preventive agents against exposure of X-ray.

Cell killing and chromosomal aberration induced by heavy-ion beams in cultured human tumor cells

International Nuclear Information System (INIS)

Takakura, K.; Funada, A.; Mohri, M.; Lee, R.; Aoki, M.; Furusawa, Y.; Gotoh, E.

2003-01-01

Full text: To clarify the relation between cell death and chromosomal aberration in cultured human tumor cells irradaited with heavy-ion beams. The analyses were carried out on the basis of the linear energy transfer (LET) values of heavy ion beams as radiation source. Exponentially growing human tumor cells, Human Salivary Gland Tumor cells (HSG cells), were irradiated with various high energy heavy ions, such as 13 keV/micrometer carbon (C) ions as low LET charged particle radiation source, 120 keV/ micrometer carbon (C) ions and 440 keV/micrometer iron (Fe) ions as high LET charged particle radiation sources.The cell death was analysed by the colony formation method, and the chromosomal aberration and its repairing kinetics was analysed by prematurely chromosome condensation method (PCC method) using calyculin A. Chromatid-type breaks, isochromatid breaks and exchanges were scored for the samples from the cells keeping with various incubation time after irradiation. The LET dependence of the cell death was similar to that of the chromosome exchange formation after 12 hours incubation. A maximum peak was around 120 keV/micrometer. However it was not similar to the LET dependence of isochromatid breaks or chromatid breaks after 12 hours incubation. These results suggest that the exchanges formed in chromosome after irradiation should be one of essential causes to lead the cell death. The different quality of induced chromosome damage between high-LET and low-LET radiation was also shown. About 89 % and 88 % chromatid breaks induced by X rays and 13 keV/micrometer C ions were rejoined within 12 hours of post-irradiation, though only 71% and 58 % of chromatid breaks induced by 120 keV/micrometer C ions and 440 keV/micrometer Fe ions were rejoined within 12 hours of post-irradiation

Aberrations of holokinetic chromosomes and associated lethality after X-irradiation of meiotic stages in Tetranychus urticae Koch (acari, tetranychidae)

International Nuclear Information System (INIS)

Tempelaar, M.J.

1979-01-01

Chromosomes of the holokinetic organization type were irradiated with X-rays in various stages of meiosis in unfertillized eggs of Tetranychus urticae Koch. Visible cytological aberrations, lethality and sterility were investigated in subsequent generations. Chromosome fragments are the most frequently occuring light-microscopically visible chromosome aberrations; bridges are not formed. Contrary to expectations, the presence of fragments appears to be positively correlated with the occurrence of lethality; loss of fragments, missegregation and the measure of damage of the broken chromosome parts are involved. In contrast with monokinetic chromosomes the earliest lethality occurs only after about 10 divisions. The ratios between different embryonic lethality types (early vs. late) differ depending on the stage irradiated: in more compact chromatin, more serious damage (i.e. more early lethality syndromes) is induced than in less compact chromatin. In the progeny of the surviving males, neither translocations nor independent fragments are found; indirect evidence indicated the occasional presence of inversions. The presumtive inversions are induced more frequently in a chromatin-compact stage (metaphase I) than in a less compact one (telophase I). (Auth.)

The effect of caffeine posttreatment on X-ray-induced chromosomal aberrations in human blood lymphocytes in vitro

International Nuclear Information System (INIS)

Natarajan, A.T.; Obe, G.

1980-01-01

The potentiating effect of caffeine on X-ray-induced chromosomal aberrations in human blood lymphocytes has been investigated, with special reference to cell cycle stages (G0 and G2). Both quantitative and qualitative differences in the yield of chromosomal aberrations were detected in caffeine-posttreated cells, depending on the cell stage irradiated. The studies on caffeine potentiating effects on X-irradiated G0 lymphocytes from normal adults, newborns, Down syndrome patients, and an ataxia telangiectasia patient pointed to interindividual variations in the response to caffeine potentiation among normal probands and a very profound effect in ataxia cells. (orig.) [de

Effects of X-irradiation on cell-cycle progression, induction of chromosomal aberrations and cell killing in ataxia telangiectasia (AT) fibroblasts

International Nuclear Information System (INIS)

Nagasawa, H.; Little, J.B.; Latt, S.A.; Lalande, M.E.

1985-01-01

Survival, cumulative labeling indices, chromosomal aberrations and cell-cycle distribution by flow microfluorometry (FMF) were studied in fibroblasts from normal and three ataxia telangiectasia (AT) families after X-irradiation during density-inhibition of growth and immediate release by subculture to low density. Homozygotic AT (proband) fibroblasts were very hypersensitive to cell killing by X-irradiation. Fibroblasts from AT heterozygotes (parents) were minimally hypersensitive, with D 0 's slightly lower than those for normal fibroblasts. There were three different response groups for a G 1 phase block induced by 400 rad of X-rays: (1) minimal or no G 1 block was observed in AT homozygote cell strains; (2) 10-20% of the cells were blocked in G 1 in normal cell strains; and (3) 50% or more of the cells were blocked in AT heterozygote strains. FMF profiles and cumulative labeling indices showed that homozygotic AT cells irradiated in plateau phase moved into the S-phase following subculture with no additional delay over non-irradiated controls. Homozygotic AT cells showed not only a 4-5 times higher frequency of X-ray-induced chromosomal aberrations than normal strains, but approximately 30% of these were of the chromatid-type. There were no differences in the frequency or type of X-ray-induced chromosomal aberrations between normal and heterozygotic AT cells. (orig.)

Effects of bleomycin and x irradiation on the frequency of chromosomal aberrations in selected connective tissue diseases

International Nuclear Information System (INIS)

Burkhardt, W.C. Jr.

1978-01-01

Whole blood lymphocytes from 28 patients with selected connective tissue disorders (6 progressive systemic sclerosis (PSS), 6 anti-nuclear antibody positive rheumatoid arthritis, 6 anti-nuclear antibody negative rheumatoid arthritis, 6 systemic lupus erythematosus, and 4 mixed connective tissue disease) and 17 controls matched for sex, age, and race were studied to determine the frequency of spontaneous as well as bleomycin and/or x-irradiation induced chromosomal aberrations. The effects of bleomycin on cultured lymphocytes were tested, but differential susceptibilities to this clastogen were not demonstrated among the disease groups and controls investigated. However, the combined effect of bleomycin and x irradiation were found to be additive in control lymphocytes, nearly additive in PSS, RA+, and SLE cultures, but reduced considerably from the expected additive value in Ra- cultures. This study indicated that peripheral blood lymphocytes from patients with connective tissue disease, as a whole, possess greater frequencies of spontaneous chromosomal aberrations than matched controls and that x rays can produce greater frequencies of chromosomal aberrations in whole blood lymphocytes of PSS patients than in suitably matched control individuals

A correlative study on the frequencies of radiation-induced chromosome aberrations in somatic and germ cells of mammals

International Nuclear Information System (INIS)

Buul, P.P.W. van

1976-01-01

A series of investigations on the correlation between the frequencies of radiation-induced chromosome aberrations in somatic and germ cells of mouse and rhesus monkey is described. In the mouse the induction of reciprocal translocations in bone-marrow cells was compared with that in spermatogonia (as scored in the descending spermatocytes). In the rhesus monkey frequencies of radiation-induced chromosome aberrations in spermatogonia and peripheral blood lymphocytes were studied. Furthermore the effect of multigeneration irradiation (69 generations with 200 rads X-rays) on the sensitivity for translocation induction in spermatogonia of male mice was studied. Frequencies of dicentric chromosomes and chromosomal deletions in cultured peripheral blood lymphocytes of 5 different types of mice were determined following in vitro irradiation with doses of 100 and/or 200 rad X-rays. To obtain more insight into the processes underlying translocation induction in spermatogonia of the mouse, fractionation experiments were conducted

Gamma induced chromosomal aberrations in meristem cells of cotton hybrids and their parental forms

International Nuclear Information System (INIS)

Kraevoj, S.Ya.; Akhmedova, M.M.; Amirkulov, D.

1977-01-01

The effect of gamma quanta on the first mitoses in the small roots of cotton hybrids and their parents results in different frequency of chromosome rearrangements in them. It has been proved that the frequency of chromosome aberrations is different in hybrids and different varieties of cotton. With increase in irradiation doses (from 10 to 30 kR) the frequency of chromosome aberrations goes up in all varieties and hybrids studies. The type of chromosome rearrangements in hybrids and their parents depends on the irradiation dose

Frequent induction of chromosomal aberrations in in vivo skin fibroblasts after allogeneic stem cell transplantation: hints to chromosomal instability after irradiation

International Nuclear Information System (INIS)

Massenkeil, G.; Zschieschang, P.; Thiel, G.; Hemmati, P. G.; Budach, V.; Dörken, B.; Pross, J.; Arnold, R.

2015-01-01

Total body irradiation (TBI) has been part of standard conditioning regimens before allogeneic stem cell transplantation for many years. Its effect on normal tissue in these patients has not been studied extensively. We studied the in vivo cytogenetic effects of TBI and high-dose chemotherapy on skin fibroblasts from 35 allogeneic stem cell transplantation (SCT) patients. Biopsies were obtained prospectively (n = 18 patients) before, 3 and 12 months after allogeneic SCT and retrospectively (n = 17 patients) 23–65 months after SCT for G-banded chromosome analysis. Chromosomal aberrations were detected in 2/18 patients (11 %) before allogeneic SCT, in 12/13 patients (92 %) after 3 months, in all patients after 12 months and in all patients in the retrospective group after allogeneic SCT. The percentage of aberrant cells was significantly higher at all times after allogeneic SCT compared to baseline analysis. Reciprocal translocations were the most common aberrations, but all other types of stable, structural chromosomal aberrations were also observed. Clonal aberrations were observed, but only in three cases they were detected in independently cultured flasks. A tendency to non-random clustering throughout the genome was observed. The percentage of aberrant cells was not different between patients with and without secondary malignancies in this study group. High-dose chemotherapy and TBI leads to severe chromosomal damage in skin fibroblasts of patients after SCT. Our long-term data suggest that this damage increases with time, possibly due to in vivo radiation-induced chromosomal instability

Induction of chromosomal aberrations in human lymphocytes by fission neutrons

International Nuclear Information System (INIS)

Silva, Marcia Augusta da; Coelho, Paulo Rogerio Pinto; Bartolini, Paolo; Okazaki, Kayo

2009-01-01

Chromosome aberrations induced by sparsely ionizing radiation (low-LET) are well known and cytogenetic analyses of irradiated human lymphocytes have been widely applied to biological dosimetry. However, much less is known about chromosome aberrations induced by densely ionizing radiation (high LET), such as that of alpha particles or neutrons. Such particles induce DNA strand breaks, as well as chromosome breakage and rearrangements of high complexity. This damage is more localized and less efficiently repaired than after X- or γ-ray irradiation. This preferential production of complex aberrations by densely ionizing radiation is related to the unique energy deposition patterns, which produces highly localized multiple DNA damage at the chromosomal level. A better knowledge of the interactions between different types of radiation and cellular DNA is of importance, not only from the radiobiological viewpoint but also for dosimetric and therapeutic purposes. The objective of the present study was to analyse the cytogenetic effects of fission neutrons on peripheral blood lymphocytes in order to evaluate structural and numerical aberrations and number of cells in the different mitotic cycles. So, blood samples from five healthy donors, 22-25 years old, of both sexes, were irradiated in the Research Reactor IEA-R1 of our Institute (IPEN/CNEN-SP) with thermal and fast neutrons at doses of 0.2; 0.3; 0.5 and 1.0 Gy. The γ contribution to the total absorbed dose was about 30%. These doses were monitored by thermoluminescent dosemeters: LiF-600 (for neutrons) and LiF-700 (for γ-rays). The data concerning structural aberrations were evaluated with regard to three parameters: percentage of cells with aberrations, number of aberrations/cell and number of dicentric/cell. The cytogenetic results showed an increase in the three parameters after irradiation with neutrons, as a function of radiation dose. Apparently, there was no influence of neutrons on the kinetics of cellular

DNA Repair Defects and Chromosomal Aberrations

Science.gov (United States)

Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

2009-01-01

Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

Cell survival and radiation induced chromosome aberrations. Pt. 2

International Nuclear Information System (INIS)

Bauchinger, M.; Schmid, E.; Braselmann, H.

1986-01-01

Human peripheral lymphocytes were irradiated in whole blood with 0.5-4.0 Gy of 220 kVp X-rays and the frequency of chromosome aberrations was determined in 1st or 2nd division metaphases discriminated by fluorescence plus giemsa staining. Using the empirical distributions of aberrations among cells, cell survival and transmission of aberrations were investigated. Considering both daughter cells, we found that 20% of fragments and 55% of dicentrics or ring chromosomes are lost during the 1st cell division; i.e. cell survival rate from 1st to 2nd generation is mainly influenced by anaphase bridging of these two-hit aberrations. Cell survival to 2nd mitosis was calculated considering this situation and compared with the survival derived from the fraction of M1 cells without unstable aberrations. The resulting shouldered survival curves showed significantly different slopes, indicating that cell reproductive death is overestimated in the latter approach. (orig.)

Use of M-FISH analysis of α-particle-induced chromosome aberrations for the assessment of chromosomal breakpoint distribution and complex aberration formation

International Nuclear Information System (INIS)

Anderson, R.M.; Sumption, N.D.; Papworth, D.G.; Goodhead, D.T.

2003-01-01

Double strand breaks (dsb) of varying complexity are an important class of damage induced after exposure to ionising radiation and are considered to be the critical lesion for the formation of radiation-induced chromosome aberrations. Assuming the basic principles of the 'Breakage and Reunion' theory, dsb represent 'breakage' and aberrations are produced from the illegitimate repair (reunion) of the resulting dsb free-'ends'. Numerous questions relate to this process, in particular, (1) do chromosomal breakpoint 'hot-spots' that represent sensitive sites for breakage and/or regions of preferential repair/mis-repair, exist? (2) Considering that individual chromosomes and chromosome regions occupy discrete territories in the interphase nucleus, could rearrangements between specific chromosomes reflect domain organisation at the time of damage? (3) Assuming the topological constraints imposed on chromatin are not dramatically influenced by the presence of dsb, then how do multiple 'ends' from different chromosomes proximally associate for mis-repair as complex chromosome aberrations? To address these questions, we have analysed the chromosome aberrations induced in peripheral blood lymphocytes after exposure to 0.5 Gy α -particles (mean of 1 α -particle/cell) using the technique of M-FISH. This technique 'paints' all the human chromosomes (excluding homologues) uniquely, allowing chromosomal mis-repair to be visualised as differential colour-junctions and in addition, enhanced DAPI banding enables gross breakpoint assignation of these colour junctions. To test for non-randomness, we are comparing the frequency of occurrence of breakpoints obtained up to now with the F98 glioma model our knowledbased on chromosome length. Similarly, the involvement of each chromosome relative to other chromosomes within individual rearrangements can be determined by assuming the volume of chromosome domains is also proportional to their length. The current data to be presented will

Possible mechanisms of chromosome aberrations. 2. Formation of aberrations after UV-irradiation

International Nuclear Information System (INIS)

Lebedeva, L.I.

1982-01-01

One of mechanisms of chromosome aberrations after UV-radiation of animal cells initiated by thymine dimerization from different dna threads (by cross joints) and finished in mitosis metaphase is discussed. The model of aberration formation, taking a count of peculiarities of chromosome ansate structure and predicting the important role of chromosome isolation during mitosis in realization of structural aberrations, is suggested. An attempt to present aberration formation under conditions of exact repair is the distinguishing feature of the model

Relationship of DNA repair and chromosome aberrations to potentially lethal damage repair in X-irradiated mammalian cells

International Nuclear Information System (INIS)

Fornace, A.J. Jr.; Nagasawa, H.; Little, J.B.

1980-01-01

By the alkaline elution technique, the repair of x-ray-induced DNA single strand breaks and DNA-protein cross-links was investigated in stationary phase, contact-inhibited mouse cells. During the first hour of repair, approximately 90% of x-ray induced single strand breaks were rejoined whereas most of the remaining breaks were rejoined more slowly during the next 5 h. The number of residual non-rejoined single strand breaks was approximately proportional to the x-ray dose at early repair times. DNA-protein cross-links were removed at a slower rate - T 1/2 approximately 10 to 12 h. Cells were subcultured at low density at various times after irradiation and scored for colony survival, and chromosome aberrations in the first mitosis after sub-culture. Both cell lethality and the frequency of chromosome aberrations decreased during the first several hours of repair, reaching a minimum level by 6 h; this decrease correlated temporally with the repair of the slowly rejoining DNA strand breaks. The possible relationship of DNA repair to changes in survival and chromosome aberrations is discussed

Biological radiation dose estimation by chromosomal aberrations analysis in human peripheral blood (dose-effect curve)

International Nuclear Information System (INIS)

Al-Achkar, W.

2001-09-01

In order to draw a dose-effect curve, experimentally gamma ray induced chromosomal aberrations in human peripheral lymphocytes from eight healthy people were studied. Samples from 4 males and 4 females were irradiated in tubes with 0.15, 0.25, 0.5, 1, 1.5, 2, 2.5 gray of gamma ray (Co 60 at dose rate 0.3 Gy/min). Irradiated and control samples were incubated in 37 centigrade for 48 hours cell cultures. Cell cultures then were stopped and metaphases spread, Giemsa stained to score the induced chromosomal aberrations. Chromosomal aberrations from 67888 metaphases were scored. Curves from the total number of dicentrics, dicentrics + rings and total numbers of breaks in cell for each individual or for all people were drawn. An increase of all chromosomal aberrations types with the elevation of the doses was observed. The yield of chromosome aberrations is related to the dose used. These curves give a quick useful estimation of the accidentally radiation exposure. (author)

Flow cytogenetics: progress toward chromosomal aberration detection

International Nuclear Information System (INIS)

Carrano, A.V.; Gray, J.W.; Van Dilla, M.A.

1977-01-01

Using clonal derivatives of the Chinese hamster M3-1 cell line, we demonstrate the potential of flow systems to karyotype homogeneous aberrations (aberrations which are identical and present in every cell) and to detect heterogeneous aberrations (aberrations which occur randomly in a population and are not identical in every cell). Flow cytometry (FCM) of ethidium bromide stained isolated chromosomes from clone 650A of the M3-1 cells distinguishes nine chromosome types from the fourteen present in the actual karyotype. X-irradiation of this parent 650A clone produced two sub-clones with an altered flow karyotype, that is, their FCM distributions were characterized by the addition of new peaks and alterations in area under existing peaks. From the relative DNA content and area for each peak, as determined by computer analysis, we predicted that each clone had undergone a reciprocal translocation involving chromosomes from two peaks. This prediction was confirmed by Giemsa-banding the metaphase cells. Heterogeneous aberrations are reflected in the flow karyotype as an increase in background, that is, an increase in area underlying the chromosome peaks. This increase is dose dependent but, as yet, the sample variability has been too large for quantitative analysis. Flow sorting of the valleys between chromosome peaks produces enriched fractions of aberrant chromosomes for visual analysis. These approaches are potentially applicable to the analysis of chromsomal aberrations induced by environmental contaminants

Chromosome aberration studies and microdosimetry with radiations of varying quality

International Nuclear Information System (INIS)

Grillmaier, R.E.; Bihy, L.; Menzel, H.G.; Schuhmacher, H.

1978-01-01

To investigate the biological effectivity of complex irradiation fields encountered in radiation protection and high LET radiation therapy and to find meaningful specification of radiation quality closely related to the biological effectivity, correlated chromosome aberration studies and microdosimetric investigations have been carried out using cyclotron produced collimated fast neutrons. Human lymphocytes have been irradiated at different dose levels in the direct beam and in different positions in the penumbra and the rates of acentric fragments and dicentrics have been determined. In identical positions microdosimetric measurements have been performed. The dose relationship of aberration rates after irradiation in the direct beam, the aberration rates observed in the penumbra and the microdosimetric quantities ysub(D), ysub(F) and y* are presented and their relations are discussed. Furthermore the dose relationship of chromosome aberrations induced by 60 Co-γ-rays has been investigated and used to establish the RBE dose relationship of cyclotron neutrons

Frequency of chromosomal aberrations in rat myelocaryocytes during long-term repeated irradiation

International Nuclear Information System (INIS)

Uryadnitskaya, T.I.; Sukhodoev, V.V.; Muksinova, K.N.

1977-01-01

In the course of a long-term daily irradiation of rats (50R/day), the frequency of chromosome aberrations in the bone marrow cells increased disproportionally to a total radiation dose which was due to the reduced frequency of chromosome damage at the intervals between daily exposures. The rate of this reduction was mainly determined by myelocaryocyte proliferation

Chromosomal aberrations induced by caffeine, 3H-thymidine and by X-rays in two L5178Y sublines of different radiosensitivity. Part 2. Effect of 2 mM caffeine on the frequency of chromosomal aberrations induced by X-radiation

International Nuclear Information System (INIS)

Bocian, E.; Bouzyk, E.; Rosiek, O.; Ziemba-Zoltowska, B.

1982-01-01

The effect of 2 mM caffeine on the frequency of X-ray induced chromatid aberrations in two sublines of L5178Y cells with different sensitivity to X-rays was examined. Cells were irradiated with 1 Gy of X-rays and treated with caffeine for 12 h after irradiation. The frequency of aberrations was estimated at time intervals from 5 to 48 h after irradiation. Caffeine increased the frequency of cells with numerous aberrations produced by X radiation in both sublines. Its potentiating effect was greater in the radiation-resistant subline L5178Y-R than in the radiation-sensitive one L5178Y-S. In caffeine-treated L5178Y-S cells chromosomal aberrations were revealed earlier than in the untreated cells. (author)

Molecular mechanisms involved in the production of chromosomal aberrations. I

International Nuclear Information System (INIS)

Natarajan, A.T.; Obe, G.

1978-01-01

Chinese hamster ovary cells (CHO) were X-irradiated in G2 stage of the cell cycle and immediately treated, in the presence of inactivated Sendai virus, with Neurospora endonuclease (E.C. 3.1.4.), an enzyme which is specific for cleaving single-stranded DNA. With this treatment, the frequencies of all types of chromosome aberrations increased when compared to X-irradiated controls. These results are interpreted as due to the conversion of some of the X-ray induced single-stranded DNA breaks into double-strand breaks by this enzyme. Similar enhancement due to this enzyme was found following treatment with methyl methanesulfonate (MMS) and bleomycin, but not following UV and mitomycin C. Addition of Micrococcus endonuclease and Neurospora endonuclease to the cells did not alter the frequencies of aberrations induced by UV. The introduction of enzymes with specific DNA-repair function offers possibilities to probe into the molecular events involved in the formation of structural chromosome aberrations induced by different classes of physical and chemical mutagens. (Auth.)

Changes of chromosome aberration rate and micronucleus frequency along with accumulated dose in continuously irradiated mice with a low dose rate of γ-rays

International Nuclear Information System (INIS)

Tanaka, Kimio; Izumi, Jun; Yanai, Takanori; Ichinohe, Kazuaki; Matsumoto, Tsuneya

2003-01-01

Chromosome aberrations in chronically exposed workers in nuclear facilities and medical radiologists have been reported. However chronological change of chromosome aberration rates along with accumulated dose has not been well studied. Chromosome aberrations and micronuclei in spleen lymphocytes were observed serially in mice continuously irradiated with a low dose rate of 20 mGy/day up to 400 days. Chromosome aberration rates were rapidly increased to 11.1% at 1 Gy, while micronucleus incidence increased at 5 Gy. After these doses their increase rates were saturated. Micronucleus incidence in bone marrow erythroblasts was higher than in spleen cells. These chronological changes of cytogenetic aberrations seem to be induced through a balance between developments of chromosome aberrations and micronuclei, and life span of spleen lymphocytes. These results will be helpful for risk assessment in low dose rate radiation exposure. (author)

X-ray- and mitomycin C (MMC)-induced chromosome aberrations in spermiogenic germ cells and the repair capacity of mouse eggs for the X-ray and MMC damage

International Nuclear Information System (INIS)

Matsuda, Yoichi; Utsugi-Takeuchi, Toyoko; Tobari, Izuo; Seki, Naohiko; Chiba Univ.

1989-01-01

Chromosome aberrations induced at the first-cleavage metaphase of eggs fertilized with sperm recovered from spermiogenic cells which had been X-irradiated and treated with mitomycin C (MMC) at various stages were observed using in vitro fertilization and embryo culture technique. Furthermore, the repair capacity of the fertilized eggs for X-ray- and MMC-induced DNA damage which was induced in the spermiogenic cells and retained in the sperm until fertilization was investigated by analysis of the potentiation effects of 2 repair inhibitors, 3-aminobenzamide (3AB) and caffeine on the yield of chromosome aberrations. The frequency of chromosome aberrations observed in the eggs fertilized with sperm recovered from speratozoa to late spermatid stage (0-8 days after X-irradiation). The induced chromosome aberrations followed by chromosome exchange through all the spermiogenic stages. The results suggest that the large amount of DNA lesions induced in spermiogenic cells by X-rays and MMC persist as reparable damage until sperm maturation and are effectively repaired in the cytoplasm of the fertilized eggs. (author). 29 refs.; 2 figs.; 2 tabs

Some characteristics and its influence factors of chromosome aberrations of germ cells induced by ionizing radiation in mice

International Nuclear Information System (INIS)

Jin Yuke; Cai Lu; Wang Xianli

1995-01-01

The chromosome aberrations of germ cells in mice by low LET ionizing radiation were systematically studied. The study demonstrated that the chromosome aberrations were linear or linearly square correlated with X-ray doses in large doses; that was linear correlated with X-ray doses in low doses. In addition, there were many factors directly influencing chromosome aberrations. The aberrations of the germ cells in males were 4.4 times of that in females. The aberrations in the germ cells were significantly higher after meiosis than before. The aberrations in secondary spermatocytes were 3.6 times of that in spermatogonia and 10 times of that in primary spermatocytes, respectively. In different phases of meiosis, the amount of chromosome aberrations in leptotene was the least, that in diaknesis was the most. The spermatogonic translocation rate receiving a whole body X-irradiation was 1.74 times of that receiving a local testis X-irradiation. The spermatogonic translocation rate of acute X-irradiation was 4.6∼6.3 times of that of chronic γ-irradiation

Cytogenetic analysis of X-ray induced chromosome aberrations in spontaneous leukaemic AKR mice

International Nuclear Information System (INIS)

Szollar, J.

1975-01-01

The increased frequency of numerical and structural chromosomal aberrations in spontaneously leukaemic AKR mice, compared with the values of healthy control CBA/H-T 6 T 6 mice, induced by X-irradiation, might be connected with the predisposition to malignant growth, probably indirectly helping the virus activation, or acting together with the immune deficiency, by creating a weaker system that is more sensitive to carcinogenic agents

Induction of chromosome aberrations and mitotic arrest by cytomegalovirus in human cells

International Nuclear Information System (INIS)

AbuBakar, S.; Au, W.W.; Legator, M.S.; Albrecht, T.

1988-01-01

Human cytomegalovirus (CMV) is potentially an effective but often overlooked genotoxic agent in humans. We report here evidence that indicates that infection by CMV can induce chromosome alterations and mitotic inhibition. The frequency of chromosome aberrations induced was dependent on the input multiplicity of infection (m.o.i.) for human lung fibroblasts (LU), but not for human peripheral blood lymphocytes (PBLs) when both cell types were infected at the GO phase of the cell cycle. The aberrations induced by CMV were mostly chromatid breaks and chromosome pulverizations that resembled prematurely condensed S-phase chromatin. Pulverized chromosomes were not observed in LU cells infected with virus stocks that had been rendered nonlytic by UV-irradiation at 24,000 ergs/mm2 or from infection of human lymphocytes. In LU cells infected with UV-irradiated CMV, the frequency of aberrations induced was inversely dependent on the extent of the exposure of the CMV stock to the UV-light. In permissive CMV infection of proliferating LU cells at 24 hr after subculture, a high percentage (greater than 40%) of the metaphase cells were arrested at their first metaphase and displayed severely condensed chromosomes when harvested 48 hr later. A significant increase (p less than 0.05) in the chromosome aberration frequency was also observed. Our study shows that CMV infection is genotoxic to host cells. The types and extent of damage are dependent on the viral genome expression and on the cell cycle stage of the cells at the time of infection. The possible mechanisms for induction of chromosome damage by CMV are discussed

Chromosomal aberrations in the bone marrow cells of mice induced by accelerated {sup 12}C{sup 6+} ions

Energy Technology Data Exchange (ETDEWEB)

Ma Xiaofei [Department of Heavy Ion Radiation Biology and Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang Hong, E-mail: zhangh@impac.ac.cn [Department of Heavy Ion Radiation Biology and Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Wang Zhenhua; Min Xianhua; Liu Yang; Wu Zhenhua [Department of Heavy Ion Radiation Biology and Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Sun Chao [Department of Heavy Ion Radiation Biology and Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Hu Bitao [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China)

2011-11-01

Highlights: {yields} 220 MeV/u {sup 12}C{sup 6+} ions is 1.5 times more effective than X-rays in inducing chromosomal aberration in bone marrow cell. {yields} The ratio of dose averaged liner energy transfer is approach the RBE. {yields} {sup 12}C{sup 6+} ions could induce severe mitosis delay. {yields} The cell cycle is not recovered 72 h following irradiation. - Abstract: The whole bodies of 6-week-old male Kun-Ming mice were exposed to different doses of {sup 12}C{sup 6+} ions or X-rays. Chromosomal aberrations of the bone marrow (gaps, terminal deletions and breaks, fragments, inter-chromosomal fusions and sister-chromatid union) were scored in metaphase 9 h after exposure, corresponding to cells exposed in the G{sub 2}-phase of the first mitosis cycle. Dose-response relationships for the frequency of chromosomal aberrations were plotted both by linear and linear-quadratic equations. The data showed that there was a dose-related increase in the frequency of chromosomal aberrations in all treated groups compared to controls. Linear-quadratic equations were a good fit for both radiation types. The compound theory of dual radiation action was applied to decipher the bigger curvature (D{sup 2}) of the dose-response curves of X-rays compared to those of {sup 12}C{sup 6+} ions. Different distributions of the five types of aberrations and different degrees of homogeneity were found between {sup 12}C{sup 6+} ion and X-ray irradiation and the possible underlying mechanism for these phenomena were analyzed according to the differences in the spatial energy deposition of both types of radiation.

Detection of chromosome aberrations in tumors lineage after irradiation process

International Nuclear Information System (INIS)

Silva, Luciana Maria Silva; Campos, Tarcisio

2002-01-01

When radioresistant cancerous cells are irradiated at level of few Gys, the interactions may not generate visible observations in the morphology of the cells or effects so intense such as death after few hours. The changes that will be observed depend on the combination of many factors that define the probability of cell surviving in response to the physical dose applied. Genetic factors may affect the cell response such as the cell sensitivity to irradiation, cancerous cell is studied when irradiated with Co-60 gamma rays. Besides the evaluation of the radiosensitivity of this cells when exposed to gamma irradiation, possible chromosomic aberrations and apoptosis were detected. (author)

Investigation of X-ray-induced chromosome aberrations in 'preleukaemic' mammalian cells

International Nuclear Information System (INIS)

Szollar, J.

1977-01-01

A study was done on the frequency of numerical and structural aberrations induced by different doses of X-ray irradiation in spontaneously leukaemic AKR mice, compared with the values of healthy control CBA/H-T 6 T 6 mice. Both were irradiated under the same conditions, but their chromosomes were affected in a different way. The number of cells containing aneuploid sets, rings, fragments, or metacentric chromosomes was significantly higher in the 2-month-old AKR mice than in the control CBA group. The increased chromosomal fragility found in AKR bone marrow cells 5-7 months before the manifestation of lymphoid leukaemia might be an important factor in the development of malignant condition. This genetic imbalance could provide a possible reason for an increase of spontaneous malfunction of the cellular system, as well as for an increased sensitivity to external factors. Thus it might be connected directly with the predisposition to malignant growth, or it has an indirect role helping virus activation, or acting together with the immune deficiency, by creating a weaker system that is more sensitive to carcinogenic agents

Effect of estradiol on radiation-induced chromosome aberrations in human lymphocytes

International Nuclear Information System (INIS)

Kanda, Reiko; Hayata, Isamu

1999-01-01

As a part of studies on physiological factors that affect radiosensitivity, we examined the in vitro effect of estradiol (E2) on the yield of radiation-induced chromosome aberrations in human peripheral lymphocytes. Lymphocytes were cultured for 3 days in the medium containing E2 at 0-100000 ng/ml. On the second day, they were irradiated by X-rays at 3 Gy, and then 2% phytohemagglutinin and 0.05 μg/ml colcemid were added to the medium. After further 48 h, mitotic indices and the yields of chromosome aberrations were examined at various E2 concentrations. E2 treatment at concentrations above 1000 ng/ml resulted in dose-related inhibition of mitosis. Repeated experiments showed that the yield of dicentrics plus centric rings in the culture containing E2 at 100 ng/ml was significantly higher than the yields at 0 ng/ml. Similarly, the yield of total chromosome breaks in the culture containing E2 at 100 ng/ml was significantly higher than that at 1 ng/ml. This study provides the direct evidence in human that radiosensitivity may vary in relation to hormonal conditions. (author)

Is 24-color FISH detection of in-vitro radiation-induced chromosomal aberrations suited to determine individual intrinsic radiosensitivity?

International Nuclear Information System (INIS)

Kuechler, A.; Wendt, T.G.; Neubauer, S.; Grabenbauer, G.G.; Sauer, R.; Claussen, U.; Liehr, T.

2002-01-01

Background: Reliable determination of intrinsic radiosensitivity in individual patients is a serious need in radiation oncology. Chromosomal aberrations are sensitive indicators of a previous exposure to ionizing irradiation. Former molecular cytogenetic studies showed that such aberrations as an equivalent of intrinsic radiosensitivity can be detected by fluorescence in-situ hybridization (FISH) techniques using whole chromosome painting (wcp) probes. However, only one up to three randomly chosen wcp probes have been applied for such approaches until now. As a random distribution of chromosomal rearrangements along the chromosomes is up to now still controversial, the power of the 24-color FISH approach should be elucidated in the present study. Methods and Material: Lymphocytes derived from lymphoblastoid cell lines of one patient with Nijmegen breakage syndrome (NBS homozygote) and of two NBS heterozygotes and peripheral blood lymphocytes of two controls were analyzed. Samples of each patient/control were irradiated in vitro with 0.0 Gy, 0.7 Gy or 2.0 Gy prior to cultivation. Chromosomal aberrations were analyzed in detail and quantified by means of 24-color FISH as an expression of the individual intrinsic radiosensitivity. Results: 24-color FISH analyses were done in a total of 1,674 metaphases. After in-vitro irradiation, 21% (0.7 Gy) or 57% (2.0 Gy) of the controls' cells, 15% (0.7 Gy) or 53% (2.0 Gy) of the heterozygotes' cells and 54% (0.7 Gy) or 79% (2.0 Gy) of the homozygote's cells contained aberrations. The highest average rates of breaks per mitosis [B/M] (0.7 Gy: 1.80 B/M, 2.0 Gy: 4.03 B/M) and complex chromosomal rearrangements [CCR] (0.7 Gy: 0.20 CCR/M, 2.0 Gy: 0.47 CCR/M) were observed in the NBS patient. Moreover, the proportion of different aberration types after irradiation showed a distinct increase in the rate of CCR combined with a decrease in dicentrics in the NBS homozygote. Conclusion: To come to a more complete picture of radiation-induced

Chromosomal aberrations in bone marrow cells of rats irradiated with different gamma-doses and protected with adeturon

International Nuclear Information System (INIS)

Ivanov, B.; Mileva, M.; Bulanova, M.; Pantev, T.

1982-01-01

Sexually mature wistor rats were irradiated on cesium gamma source ''IGUR-1'' with emissive power 3.25 mA/kg. The animals were divided in five groups of 10 rats each. They were irradiated respectively with 0.0129 C/kg, O, 0.0258 C/kg, 0.0516 C/kg, 0.1032 C/kg and control group. Five animals of each group received 300 meg/g weight Adeturone 15 minutes before exposure. The animals were sacrifices 20 hours after irradiation and preparations made from bone-marrow cells for chromosomal analysis. The number of structural chromosomal aberrations, aberrant cells and total number of aberrations in protected and in nonprotected cells were read under high-power microscope. The results were statistically processed by variation and regression analysis. It was found that Adeturone displays strong protective effect on the hereditary cell structures in all animals exposed to doses higher than 0.0129 C/kg, with the exception of chromatid fragments at a dose of 0.0258 C/kg. Mathematical models of the curves of the yields of chromatid and chromosomal fragments, aberrant cells and total number of aberrations in protected and nonprotected animals were described. (authors)

Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

Science.gov (United States)

Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

2009-01-01

A detailed understanding of the biological effects of heavy nuclei is needed for space radiation protection and for cancer therapy. High-LET radiation produces more complex DNA lesions that may be non-repairable or that may require additional processing steps compared to endogenous DSBs, increasing the possibility of misrepair. Interplay between radiation sensitivity, dose, and radiation quality has not been studied extensively. Previously we studied chromosome aberrations induced by low- and high- LET radiation in several cell lines deficient in ATM (ataxia telangactasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. We found that the yields of both simple and complex chromosomal aberrations were significantly increased in the DSB repair defective cells compared to normal cells. The increased aberrations observed for the ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex aberrations, while the linear dose-response term was significantly higher in NBS cells only for simple exchanges. These results point to the importance of the functions of ATM and NBS in chromatin modifications that function to facilitate correct DSB repair and minimize aberration formation. To further understand the sensitivity differences that were observed in ATM and NBS deficient cells, in this study, chromosomal aberration analysis was performed in normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, or Mirin, an MRN complex inhibitor involved in activation of ATM. We are also testing siRNA knockdown of these proteins. Normal and ATM or NBS suppressed cells were irradiated with gamma-rays and chromosomes were collected with a premature chromosome

Elimination of radiation-induced chromosome damages in human peripheral blood lymphocyte cultures. 2. The frequency of aberrations in the first-fifth post-irradiation mitosis

International Nuclear Information System (INIS)

Pyatkin, E.K.; Pokrovskaya, V.N.; Nugis, V.Yu.

1982-01-01

The number of chromosome aberrations in 1.-5. mitoses cultivated from lymphocyte PHA of peripheric man blood after gamma irradiation in vitro in 1e5; 3 and 6 Gy has been determined. For all the doses, as the cells passed 1. and successive postradiation divisiops, observed was the decrease in the number of aberrant metaphases and all the aberrations of the chromosomal typee at that their elimination rate increases with the dose increase. No considerable differences in the frequency of pair fragments in 1.-4. mitosis after irradiation in 1,5 Gy dose, in 1.-3. mitoses after irradiation in 3 Gy dose and in 1.-2. mitoses after irradiation in 6 Gy dose were found. In lymphocyte cultures irradiated in 3 and 6 Gy doses the number of dicentries in 2. mitosis was approximately 2 times smaller than in 1. mitosis and in 3. mitosis two times smaller than in 2. mitosis. In 1. mitosis almost all the dicentrics have accompanying pair fragments in 2. and 3. mitoses a share of the dicentrics without fragments constituted about 30-70 %, and in 4.-5. mitoses amounted to 95-100 %. The reduction of the number of irregular chromosomes in the process of cell passing of 1. and successive postradiation mitosis was noted only during lymphocyte investigation irradiated in 6 Gy. At 1,5 and 3 Gy doses these aberration frequency in 1.-5. and 1.-4. mitoses were nearly the same

Prevention of radiation-induced chromosomal aberrations in bone marrow of mice by Indian medicinal plant, Alstonia scholaris

International Nuclear Information System (INIS)

Jahan, Swafiya; Ranuchaudhary; Goyal, P.K.

2007-01-01

Full text: It is well established that ionizing radiation can damage biologically important macromolecules such as DNA via both direct and indirect mechanisms. Chromosomal aberrations are a measure of direct effects on the genetic material and serve as useful biological dosimeter. With the realization of deleterious effects of ionizing radiation, a need was felt to protect human beings against these harmful effects by using physical and/or chemical means. Numerous chemical compounds have been tested for their ability to protect against ionizing radiation. Despite extensive screening of several synthetic compounds for radio protective activity, no single compound has emerged as a good radio protector so far. The plants have been the companion of man since time immemorial, providing several useful drugs for the treatment of various ailments. Therefore, it is natural that the choices of alternative radio protectors would include plants and plants products. However, some plants have been tested for radio protective action but a detailed study, with all possible end points, is still lacking. Hence, screening of natural products presents a major avenue for the discovery of new radioprotective drugs. Alstonia scholaris, a non toxic herbal preparation, has been reported to be clinically effective in treating syphilis insanity and epilepsy. A. scholaris has also been reported to inhibit liver injuries. These results encourage us to conduct further experiments to prove its radioprotective potential. The present study was performed to verify the radioprotective capacity of Alstonia scholaris on radiation-induced clastogenic change in term of chromosomal aberrations. For this purpose, one group of male Swiss albino mice was exposed to 5 Gy gamma radiation to serve as the control while the other group received Alstonia scholaris bark extract (100 mg/kg b. wt.) orally for 5 consecutive days before irradiation to serve as experimental. Such animals were pretreated with colchicine

Chromosomal instability in the progeny of irradiated parents

International Nuclear Information System (INIS)

Voro btsova, I.E.; Vorobyova, M.V.; Bogomazova, A.N.

1997-01-01

Genomic instability have been demonstrated in irradiated cells as the increased frequency of sporadic chromosome aberrations persisted over multiple generations of cell divisions. We found that chromosomal instability characterized as well the somatic cells of irradiated parents progeny. It means that radiation induced genomic instability can be transmitted via germ line cells. As a measure of instability the sensitivity of chromosomes to radiation was estimated. In animal experiments the irradiation of mature germ cells of male rats (dose - 4.5 Gy of X-rays) increase the frequency of chromosome aberrations induced by challenging irradiation in regenerating hepatocytes, in bone marrow cells and in fetal fibroblasts in the progeny of irradiated male rats. The chromosomal sensitivity of cultivated lymphocytes to in vitro irradiation (1.5 Gy of γ(rays 137 Cs) is increased in the children born parents undergone antitumor radiotherapy or worked as 'liquidators' of Chernobyl accident consequences before conception in comparison to the children of unexposed parents. The cytogenetic radiosensitivity of lymphocytes to irradiation in vitro is also increased in children evacuated from contaminated by radionuclides areas ('positive' control group). The increased spontaneous frequency of chromatid-type acentric was found in all group of children with irradiation history. The instability of genome of irradiated parents progeny seems could be the mechanism of these health effects. (authors)

Structural and numerical chromosome aberration inducers in liver micronucleus test in rats with partial hepatectomy.

Science.gov (United States)

Itoh, Satoru; Hattori, Chiharu; Nagata, Mayumi; Sanbuissho, Atsushi

2012-08-30

The liver micronucleus test is an important method to detect pro-mutagens such as active metabolites not reaching bone marrow due to their short lifespan. We have already reported that dosing of the test compound after partial hepatectomy (PH) is essential to detect genotoxicity of numerical chromosome aberration inducers in mice [Mutat. Res. 632 (2007) 89-98]. In naive animals, the proportion of binucleated cells in rats is less than half of that in mice, which suggests a species difference in the response to chromosome aberration inducers. In the present study, we investigated the responses to structural and numerical chromosome aberration inducers in the rat liver micronucleus test. Two structural chromosome aberretion inducers (diethylnitrosamine and 1,2-dimethylhydrazine) and two numerical chromosome aberration inducers (colchicine and carbendazim) were used in the present study. PH was performed a day before or after the dosing of the test compound in 8-week old male F344 rats and hepatocytes were isolated 4 days after the PH. As a result, diethylnitrosamine and 1,2-dimethylhydrazine, structural chromosome aberration inducers, exhibited significant increase in the incidence of micronucleated hepatocyte (MNH) when given either before and after PH. Colchicine and carbendazim, numerical chromosome aberration inducers, did not result in any toxicologically significant increase in MNH frequency when given before PH, while they exhibited MNH induction when given after PH. It is confirmed that dosing after PH is essential in order to detect genotoxicity of numerical chromosome aberration inducers in rats as well as in mice. Regarding the species difference, a different temporal response to colchicine was identified. Colchicine increased the incidence of MNH 4 days after PH in rats, although such induction in mice was observed 8-10 days after PH. Copyright © 2012 Elsevier B.V. All rights reserved.

Chromosomal Aberrations in Humans Induced by Urban Air Pollution

DEFF Research Database (Denmark)

Knudsen, Lisbeth E.; Norppa, Hannu; Gamborg, Michael O.

1999-01-01

We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes as a biomar......We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes...... that long-term exposure to urban air pollution (with traffic as the main contributor) induces chromosome damage in human somatic cells. Low DNA repair capacity and GSTM1 and NAT2 variants associated with reduced detoxification ability increase susceptibility to such damage. The effect of the GSTM1 genotype......, which was observed only in the bus drivers, appears to be associated with air pollution, whereas the NAT2 genotype effect, which affected all subjects, may influence the individual response to some other common exposure or the baseline level of chromosomal aberrations....

Detection of chromosomal instability in α-irradiated and bystander human fibroblasts

International Nuclear Information System (INIS)

Ponnaiya, Brian; Jenkins-Baker, Gloria; Bigelow, Alan; Marino, Stephen; Geard, Charles R.

2004-01-01

There is increasing evidence biological responses to ionizing radiation are not confined to those cells that are directly hit, but may be seen in the progeny at subsequent generations (genomic instability) and in non-irradiated neighbors of irradiated cells (bystander effects). These so called non-targeted phenomena would have significant contributions to radiation-induced carcinogenesis, especially at low doses where only a limited number of cells in a population are directed hit. Here we present data using a co-culturing protocol examining chromosomal instability in α-irradiated and bystander human fibroblasts BJ1-htert. At the first cell division following exposure to 0.1 and 1 Gy α-particles, irradiated populations demonstrated a dose dependent increase in chromosome-type aberrations. At this time bystander BJ1-htert populations demonstrated elevated chromatid-type aberrations when compared to controls. Irradiated and bystander populations were also analyzed for chromosomal aberrations as a function of time post-irradiation. When considered over 25 doublings, all irradiated and bystander populations had significantly higher frequencies of chromatid aberrations when compared to controls (2-3-fold over controls) and were not dependent on dose. The results presented here support the link between the radiation-induced phenomena of genomic instability and the bystander effect

Chromosomal aberrations induced by alpha particles

International Nuclear Information System (INIS)

Guerrero C, C.; Brena V, M.

2005-01-01

The chromosomal aberrations produced by the ionizing radiation are commonly used when it is necessary to establish the exposure dose of an individual, it is a study that is used like complement of the traditional physical systems and its application is only in cases in that there is doubt about what indicates the conventional dosimetry. The biological dosimetry is based on the frequency of aberrations in the chromosomes of the lymphocytes of the individual in study and the dose is calculated taking like reference to the dose-response curves previously generated In vitro. A case of apparent over-exposure to alpha particles to which is practiced analysis of chromosomal aberrations to settle down if in fact there was exposure and as much as possible, to determine the presumed dose is presented. (Author)

Biological dosimetry in radiation accidents. Dose-response curve by chromosomal aberrations analysis

International Nuclear Information System (INIS)

Hadjidekova, V.; Hristova, R.; Atanasova, P.; Popova, L.; Stainova, A.; Bulanova, M.; Georgieva, I.; Vukov, M.

2005-01-01

The aim of this paper is to obtain a dose-response relationship for chromosomal aberrations induced in human lymphocytes after in vitro irradiation. Peripheral blood samples of 7 different donors were used. The blood irradiation was done with Cs137 gamma-rays at different doses: 0.0, 0.05, 0.1, 0.25, 0.5, 0.75, 1.0, 1.5, 2.0 and 3.0 Gy. Lymphocyte cultures were established and maintain for 48 hours at 37 0 C in CO 2 incubator for chromosomal aberration analysis. The dose response relationship has been established based on dysenteric and ring chromosomes yield. The relationship can be described by the following equation: Y = 0.0274D + 0.0251 D 2 , where (Y) = dysenteric and ring chromosomes yield, (D) = radiation dose obtained. EXCEL software was established for calculation of the received dose by using this equation, as a whole body equivalent dose acute irradiation

Relationship between chromosomal aberration of germ cells and dominant lethal mutation in male mice after low dosage of X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Mingdong, Wang; Baochen, Yang; Yuke, Jin [Bethune (N.) Medical Univ., Changchun, JL (China). Dept. of Gentics

1989-01-01

The relationship between chromosomal aberration adn dominant mutation in spermatocytes of late pachytene phase in male mice after a single X-irridiation was reported. It was found that the frequency of aberrant cells was correlative to the rate of fetal death, the latter was being about 2.5 times as high as the former. The frequency of dominant lethal mutation induced by X-irradiation is 2.1995x10{sup -3} gamete {center dot} 10 mGy.

Effects of cisplatin and γ-irradiation on cell survival, the induction of chromosomal aberrations and apoptosis in SW-1573 cells

International Nuclear Information System (INIS)

Bergs, J.W.J.; Franken, N.A.P.; Cate, R. ten; Bree, C. van; Haveman, J.

2006-01-01

Purpose: Cisplatin was found to radiosensitize SW-1573 cells by inhibition of PLDR. Therefore, it was investigated whether cisplatin combined with γ-radiation leads to an increase in the number of chromosomal aberrations or apoptotic cells compared with radiation alone. Methods: Confluent cultures of the human lung carcinoma cell line SW-1573 were treated with 1 μM cisplatin for 1 h, 4 Gy γ-radiation, or a combination of both. Cell survival was studied by the clonogenic assay. Aberrations were analysed by FISH in prematurely condensed chromosomes (PCC) and the induction of apoptosis by counting fragmented nuclei. Results: A radiosensitizing effect of cisplatin on cell survival was observed if time for PLDR was allowed. An increased number of chromosomal fragments were observed immediately after irradiation compared with 24 h after irradiation whereas color junctions are only formed 24 h after irradiation. No increase in chromosomal aberrations was found after combined treatment, but a significantly enhanced number of fragmented nuclei were observed when confluent cultures were replated after allowing PLDR. Conclusion: The inhibition of PLDR by cisplatin in delayed plated SW-1573 cells did not increase chromosomal aberrations, but increased the induction of apoptosis

Influence of caffeine on chromosome lesions induced by chemical mutagens and radiation. 2

International Nuclear Information System (INIS)

Dimitrov, B.

1977-01-01

The modifying influence of caffeine on γ-ray induced chromosome lesions was studied by chromosome aberration anaysis. Caffeine was applied as a pre- and post-treatment agent following seed (G 1 ) and root meristem (G 2 and S) irradiation of C.capillaris. The frequency of chromosome aberrations induced in G 1 was changed neither by post- nor by pre-treatment with caffeine. This fact proves the lack of caffeine modifying effect. Applied as a post-treatment agent caffeine enhances considerably the frequency of chromosome aberrations induced in root meristem cells. This is especially valid for G 2 irradiated cells, while in S cells no synergistic effect was established between induced chromosome lesions and caffeine. The enhancement of chromosome aberration frequency produced in G 2 shows a clearly manifested dependence on the time (moment) of caffeine application post irradiation. Most considerable enhancement was obtained following post-treatment with caffeine immediately after irradiation. In the following intervals - 15 and 30 min - it decreases progressively, while after 60, 180 and 300 min no enhancing effect is observed. The probable causes for the manifestation and the lack of synergistic effect between chromosome lesions induced in the various mitotic cycle phases and caffeine are discussed. (author)

Cell survival and chromosomal aberrations in CHO-K1 cells irradiated by carbon ions

Energy Technology Data Exchange (ETDEWEB)

Czub, J. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Banas, D. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Holycross Cancer Center, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Blaszczyk, A. [Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Braziewicz, J. [Institute of Physics, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Holycross Cancer Center, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Buraczewska, I. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Choinski, J. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, 02-093 Warsaw (Poland); Gorak, U. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland); Jaskola, M.; Korman, A. [Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Lankoff, A.; Lisowska, H. [Institute of Biology, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland); Lukaszek, A. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland); Main School of Fire Service, ul. Slowackiego 52/54, 01-629 Warsaw (Poland); Szeflinski, Z. [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland)], E-mail: szef@fuw.edu.pl; Wojcik, A. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Institute of Biology, Swietokrzyska Academy, ul. Swietokrzyska 15, 25-406 Kielce (Poland)

2009-03-15

Chinese hamster ovary CHO-K1 cells were exposed to high LET {sup 12}C-beam (LET: 830 keV/{mu}m) in the dose range of 0-6 Gy and to {sup 60}Co irradiation and the RBE value was obtained. Effects of {sup 12}C-beam exposure on cell survival and chromosomal aberrations were calculated. The chromosomal aberration data were fitted with linear equation. The distribution of aberration in cells was examined with a standard u-test and used to evaluate the data according to Poisson probabilities. The variance to the mean ratio {sigma}{sup 2}/Y and the dispersion index (u) were determined. Overdispersion was significant (p<0.05) when the value of u exceeded 1.96.

Chromosomal aberrations of blood lymphocytes induced in vitro by radon-222 daughter α-irradiation

International Nuclear Information System (INIS)

Pohl-Rueling, J.; Lettner, H.; Hofmann, W.; Atzmueller, C; Eckl, P.; Haas, O.A.; Obe, G.; Grell-Buechtmann, I.; Van Buul, P.P.W.; Natarajan, A.T.; Schroeder-Kurth, T.; Sasaki, M.S.; Fischer, P.; Kubiak, R.

2000-01-01

Blood samples were irradiated in vitro with α-rays emitted from short-lived radon decay products dissolved in the culture medium at doses between 0.03 and 41.4 mGy. The data were collected from experiments conducted during the period 1984-1992 and comprise a total of about 64000 scored metaphases. For statistical reasons, only 60,022 metaphases were used for the subsequent analysis. The results for total chromosome aberrations and dicentrics indicate a linear dose dependence in the dose range above about 10 mGy, consistent with other experimental observations. At doses below about 10 mGy, aberration frequencies cannot be linearly extrapolated from higher doses, suggesting that there is no dependence on dose within a certain low-dose range. In addition, a statistically significant minimum has been observed at a dose of about 0.03 mGy, which is consistently lower than the related control values. The behavior of the aberration frequencies in the low-dose region seems to be influenced by the control values, which also depend on the environmental radiation burdens to the donors before blood sampling and thus were significantly affected by the Chernobyl fallout

Gene mutations, chromosome aberrations and survival after X-ray irradiation of cultured Chinese hamster cells at cysteamine protection

International Nuclear Information System (INIS)

Elisova, I.V.; Feoktistova, I.P.

1983-01-01

The culture of Chinese hamster cells (clone 431) has been used to study cysteamine action on mutagenous effect of X-rays, determined by the induction of resistance of gene mutations to 6-thioguanine and chromosomal abberations, as well as on the reproductive form of death of irradiated cells. Dose--- effect curves are obtained under conditions of irradiation with and without protector. The factor of dose alteration is 2.0 for chromosomal aberrations and cell survival, and 2.8 for gene mutations. It is sUpposed that cysteamine affects the general mechanisms, which take part in the realis zation of injuries that bring about gene mutations, chromosomal aberrations and cell lethality

Hyperthermic radiosensitization of synchronous Chinese hamster cells: relationship between lethality and chromosomal aberrations

International Nuclear Information System (INIS)

Dewey, W.C.; Sapareto, S.A.; Betten, D.A.

1978-01-01

Synchronous Chinese hamster cells in vitro were obtained by mitotic selection. The cells were heated at 45.5 0 C for 4 min in mitosis, 11 min in G 1 , or 7 min in S sphase and then x-irradiated immediately thereafter. Colony survival from heat alone was 0.30 to 0.45, and the frequency of chromosomal aberrations induced by heat was 0.00, 0.14, or 0.97 for heat treatments during M, G 1 , or S, respectively. As shown previously, lethality from hyperthermia alone is due to chromosomal aberrations only when the cells are heated during S phase. The log survival (D 0 /sup approximately/ = 80 rad) and aberration frequency curves for cells irradiated during mitosis were linear, and the only effect of hyperthermia was to shift the curves in accord with the effect from heat alone. Thus, hyperthermia did not radiosensitize the mitotic cells. The cells irradiated in G 1 were more resistant (D 0 /sup approximately/ = 100 rad) than those irradiated in mitosis, and the survival and aberration frequency curves both had shoulders. The primary effect of hyperthermia was to greatly reduce the shoulders of the curves and to increase the slopes by about 23%. The cells irradiated in S were the most resistant (D 0 /sup approximately/ = 140 rad), and the survival and aberration frequency curves both had large shoulders. For both end points of lethality and chromosomal aberrations, heat selectively radiosensitized S-phase cells relative to G 1 cells by removing most of the shoulder and increasing the slope by about 45%. For cells treated in G 1 or S, the increase in radiosensitization following hyperthermia can be accounted for by an increase in the frequency of chromosomal aberrations

Chromosomal aberrations induced by 12C6+ ions and 6Co γ-rays in mouse immature oocytes

International Nuclear Information System (INIS)

Zhang Hong; Duan Xin; Yuan Zhigang; Li Wenjian; Zhou Guangming; Zhou Qingming; Bing Liu; Min Fengling; Li Xiaoda; Xie Yi

2006-01-01

The ovaries of Kun-Ming strain mice (3 weeks) were irradiated with different doses of 12 C 6+ ion or 6 Co γ-ray. Chromosomal aberrations were analyzed in metaphase II oocytes at 7 weeks after irradiation. The relative biological effectiveness (RBE) of 12 C 6+ ion was calculated with respect to 6 Co γ-ray for the induction of chromosomal aberrations. The 12 C 6+ ion and 6 Co γ-ray dose-response relationships for chromosomal aberrations were plotted by linear quadratic models. The data showed that there was a dose-related increase in frequency of chromosomal aberrations in all the treated groups compared to controls. The RBE values for 12 C 6+ ions relative to 6 Co γ-rays were 2.49, 2.29, 1.57, 1.42 or 1.32 for the doses of 0.5, 1.0, 2.0, 4.0 or 6.0 Gy, respectively. Moreover, a different distribution of the various types of aberrations has been found for 12 C 6+ ion and 6 Co γ-ray irradiations. The dose-response relationships for 12 C 6+ ion and 6 Co γ-ray exhibited positive correlations. The results from the present study may be helpful for assessing genetic damage following exposure of immature oocytes to ionizing radiation

The effects of X-ray energy and an iodine-based contrast agent on chromosome aberrations

International Nuclear Information System (INIS)

Matsubara, Sho; Kubota, Nobuo; Katoh, Tsuguhisa; Yoshino, Norio; Sasaki, Takehito; Sasaki, Masao S.

1994-01-01

A study was undertaken to evaluate the effect of combining irradiation with X rays of various energies and an iodine-based contrast agent on the induction of chromosome aberrations in the peripheral lymphocytes of blood samples taken from healthy young donors. Although no enhancement of the effect of radiation was induced when blood samples with the iodine-based contrast agent were given 35 kV X irradiation, an 80 kV X-ray exposure induced an enhanced level of chromosome aberrations, and a 250 kV X irradiation, an enhancement of the frequencies of chromosome aberrations was seen in blood samples with the iodine-based contrast agent, especially when a Lucite phantom was employed in studies to increase the scattered rays. It was thus shown by microdosimetric analysis that X irradiation combined with an iodine-based contrast agent causes an enhancement of the absorbed radiation dose, which is dependent on the X-ray energies employed. This phenomenon may have clinical use in the radiotherapeutic management of tumors, although further extensive studies of tumor vascularity must be pursued before this can be applied clinically. 21 refs., 8 figs., 3 tabs

A comparative study of dose distribution of a high-energy electron beam and chromosome aberration frequencies

International Nuclear Information System (INIS)

Matsubara, Sho; Kuwabara, Yuji; Horiuch, Junichi; Suzuki, Soji; Hoshina, Masao; Kato, Tsuguhisa

1986-01-01

Peripheral blood was exposed to a 14 MeV electron beam in a plastic tube set in a test-tube stand immersed in a water tank. The chromosome aberration frequencies induced by irradiation of about 95% of peak dose at a depth of 31 mm were found to be higher in value than those induced at a depth of 17 mm where the peak dose had been determined physically. Three gray of irradiation given to whole blood in the presence of contrast medium gave rise to a slight enhancement of radiation-induced chromosome aberration frequencies in the lymphocytes exposed at a depth of 17 mm, but a slight decrease at 31 mm. (author)

In-situ fluorescence hybridization applied to biological dosimetry: contribution of automation to the counting of radio-induced chromosome aberrations

International Nuclear Information System (INIS)

Germain Thomas Roy, Laurence

1999-01-01

The frequency of chromosome aberrations on peripheral blood lymphocytes is a dose indicator in the case of ionizing radiations over-exposure. Stable chromosome aberrations (translocations, insertions) are visualized after labelling of some chromosomes using the fluorescence in-situ hybridization (FISH). The study of the use of the FISH technique in biological dosimetry is done with dose-effect curves. It seems that a bias is introduced during the observation of chromosome aberrations involving only 3 pairs of chromosomes. In order to avoid this bias, it would be useful to test the feasibility of using the multi-FISH technique in biological dosimetry. Moreover, this type of chromosome aberration changes with the type of irradiation. It is thus important to define the aberrations to be considered when the FISH technique is used. In order to reduce the time of image analysis, the CYTOGEN system, developed by IMSTAR company (Paris, France) has been adapted to the needs of biological dosimetry. This system allows to localize automatically the metaphases on the slide, which reduces the observation time by 2 or 4. An automatic detection protocol for chromosome aberrations has been implemented. It comprises the image capture, the contours detection and the classification of some chromosome aberrations. The different steps of this protocol have been tested in order to check that no bias is introduced by the automation. However, because radio-induced aberrations are rare events, it seems that a totally automatic system is not foreseeable. A semi-automatic analysis is more suitable. The use of the Slit-Scan technology (Laboratory of applied physics, Heidelberg, Germany) in biological dosimetry has been studied too. This technique allows to analyze rapidly a huge number of chromosomes. A good correlation has been observed between the dicentric frequency measured automatically and by manual counting. The system is under development and should be adapted to the detection of

Chromosomal aberrations of the Chinese hamster cell line V79 after irradiation with X-rays and heavy ions

International Nuclear Information System (INIS)

Mueller, W.

1985-02-01

The study on hand examines chromosomal aberrations in Chinese hamster 79 cells. Irradiation involved a number of heavy ions ranging from neon to uranium with an energy variation between 0.3 and 20 MeV/u. Linear energy transfer ranged from 270 to 16,300 keV/μm. X-ray tests were run for reasons of comparison. Experiments showed the following results: 1) Aberration rate increases in dependence of nuclear charge number or LET resp. 2) The distribution of the chromosome-damage instances found differed markedly from corresponding measurements following irradiation with thinly ionizing radiation. In contrast to x-irradiation, it is possible, therefore, to obtain high aberration yields in preparations made immediately after irradiation. 3) The maximum of aberration yield after heavy-ion irradiation could be shown to occur as early as 4h after irradiation. This is true in x-irradiation for but small doses. 4) The radiation-sensitizing effect of caffeine and its action on the repair system of the cell could be confirmed for x-irradiation and could be described for heavy ions for the first time. 5) The radiation-protection effect of cysteamine could be re-affirmed for thinly ionizing radiation, however, it could not be verified for heavy ions. 6) Irradiation of cells by means of particles of a defined range supports the hypothesis that the particularly radiation-sensitive regions of the nucleus membrane constitute the cell's crucial target. (orig./MG) [de

Chromosomal aberrations in peripheral blood lymphocytes of prostate cancer patients treated with IMRT and carbon ions

International Nuclear Information System (INIS)

Hartel, Carola; Nikoghosyan, Anna; Durante, Marco; Sommer, Sylwester; Nasonova, Elena; Fournier, Claudia; Lee, Ryonfa; Debus, Juergen; Schulz-Ertner, Daniela; Ritter, Sylvia

2010-01-01

Background and purpose: To investigate the cytogenetic damage in blood lymphocytes of patients treated for prostate cancer with different radiation qualities and target volumes. Materials and methods: Twenty patients receiving carbon-ion boost irradiation followed by IMRT or IMRT alone for the treatment of prostate cancer entered the study. Cytogenetic damage induced in peripheral blood lymphocytes of these patients was investigated at different times during the radiotherapy course using Giemsa staining and mFISH. A blood sample from each patient was taken before initiation of radiation therapy and irradiated in vitro to test for individual radiosensitivity. In addition, in vitro dose-effect curves for the induction of chromosomal exchanges by X-rays and carbon ions of different energies were measured. Results: The yield of chromosome aberrations increased during the therapy course, and the frequency was lower in patients irradiated with carbon ions as compared to patients treated with IMRT with similar target volumes. A higher frequency of aberrations was measured by increasing the target volume. In vitro, high-LET carbon ions were more effective than X-rays in inducing aberrations and yielded a higher fraction of complex exchanges. The yield of complex aberrations observed in vivo was very low. Conclusion: The investigation showed no higher aberration yield induced by treatment with a carbon-ion boost. In contrast, the reduced integral dose to the normal tissue is reflected in a lower chromosomal aberration yield when a carbon-ion boost is used instead of IMRT alone. No cytogenetic 'signature' of exposure to densely ionizing carbon ions could be detected in vivo.

The Relevance of Chromosome Aberration Yields for Biological Dosimetry After Low-Level Occupational Irradiation

Energy Technology Data Exchange (ETDEWEB)

Bauchinger, M.; Schmid, E.; Hug, O. [Gesellschaft fuer Strahlenforschung, Institut fuer Biologie, Neuherberg, Federal Republic of Germany (Germany); Strahlenbiologisches Institut der Universitaet Muenchen, Federal Republic of Germany (Germany)

1971-06-15

The usefulness of chromosome analysis for biological dosimetry has been tested in two groups of persons occupationally exposed to radiation: (I) in nurses employed in gynaecological radiology, exposed especially when handling radium inserts; and (II) in nuclear industry workers, all of which were exposed to external gamma irradiation and some of them also to internal radiation after incorporation of various radionuclides. The total dose registered with personal dosimeters ranged in Group 1 from 0.1 to 91.1 rem accumulated over working periods of 0.1 to 13 years, and in Group II from 1.0 to 18.2 rem accumulated over 1 to 9 years. Compared with unexposed controls, both groups exhibit a significant increase of cells with chromosome aberrations as well as larger numbers of breaks per cell. Dicentrics and rings could be observed in some cells, providing good evidence for previous radiation exposure, since these types of aberrations are extremely rare events in unexposed individuals. No correlation between the aberration yields and the film badge values could be demonstrated in Group II. Also, in Group I the fluctuations from individual to individual are rather high. Nevertheless, a positive correlation to the ''dose'' was obtained. Even a sub-group of the nurses that had only been exposed to 20 rem showed significantly more aberrations than control persons. From the results obtained, type and frequency of chromosome aberrations may be considered an indicator of radiation exposure even at the low doses. The reasons for lack of correspondence of chromosome aberration yields and the results of personal monitoring procedures are discussed in detail. (author)

Chromosome aberration analysis for biological dosimetry: a review

International Nuclear Information System (INIS)

Paul, S.F.D.; Venkatachalam, P.; Jeevanram, R.K.

1996-01-01

Among various biological dosimetry techniques, dicentric chromosome aberration method appears to be the method of choice in analysing accidental radiation exposure in most of the laboratories. The major advantage of this method is its sensitivity as the number of dicentric chromosomes present in control population is too small and more importantly radiation induces mainly dicentric chromosome aberration among unstable aberration. This report brings out the historical development of various cytogenetic methods, the basic structure of DNA, chromosomes and different forms of chromosome aberrations. It also highlights the construction of dose-response curve for dicentric chromosome and its use in the estimation of radiation dose. (author)

A comparative study on the frequencies of radiation-induced chromosome aberrations in the somatic and germ cells in mouse and monkey

International Nuclear Information System (INIS)

Sobels, F.H.

1976-06-01

Two systems were mainly used for studying the relationship between radiation induced chromosome aberration frequencies in somatic and germ cells. The first consists of reciprocal translocation induced in bone-marrow cells of mice compared to reciprocal translocation induced spermatogonia (scored in descending spermatocytes) of the same mice. Dose-response curves for induced aberrations in both cell types (0-100-200-300-400-500 and 600 R X-rays) and dose rate effects indicated that (130-1.92-0.0287 R/min) of a 400 R γ-ray exposure of the two cell types mitotically dividing germ cells respond to radiation similarly to mitotic dividing germ cells. Clonal proliferation or selective elimination of aberration-carrying cells, and other post-irradiation factors can, however, cause great differences in absolute aberration frequencies. A similar study was attempted, using the rhesus monkey as a second system. Its bone-marrow cells were proved unsuitable for induced reciprocal translocations. Stimulated peripheral blood lymphocytes were studied instead. Following 100, 200 and 300 R of X-rays, the frequencies of induced dicentric chromosomes were compared to those of induced reciprocal translocations in spermatogonia. Human peripheral blood was studied similarly. It was concluded that: (a) The absolute frequencies of chromosome aberrations in somatic and germ cells of the rhesus monkey are low compared to most other mammalian species. (b) The ratio between dicentric frequencies and reciprocal translocation frequencies at 100 R and 200 R differed significantly from 4:1 reported for mouse and Chinese hamster and 2:1 for marmoset and man. (c) Although the numbers of 'effective chromosome arms' in man and rhesus monkey are similar (81 vs 83), the rhesus monkey showed at all doses a lower rate of induction of dicentrics in blood lymphocytes than man, reaching statistical significance at the 300 R level

Dose response relationships and analysis of primary processes of radiation-induced chromosomal aberrations in human peripheral lymphocytes

International Nuclear Information System (INIS)

Schmid, E.

1977-02-01

Human peripheral lymphocytes were irradiated with 220 kV X-rays, 3 MeV electrons and 15 MeV neutrons. The frequency of dicentric, acentric and atypical chromosomes and the exhange aberrations were measured and dose effect curves were constructed. The aim is to prepare the chromosome analysis to a biological dosimetry. The aberration findings could be adapted to the linear-quadrativ model y = c+ αD + βD 2 . With increasing LET the quantity lambda increased which is a measure for the share of the linear and quadratical components of the dose effect obtained. In case of electrons the RBE-values increased with increasing doses. In the case of neutrons they had their maximum in the low dose range. The feed back distances which lead to formation of primary lesions are for X-rays and electrons approximately 1 μm, for neutrons 1.7 μm. In a fractionation experiment with X-rays, the time of formation of exchange aberrations in radiation-induced primary breaks was measured. The number of dicentric chromosomes decreased with increasing time, while the intercellular distribution was not changed. The number of primary breaks decreasing per temporal interval is proportional to the number of the existing primary breaks. The average feed back time during which the primary breaks lead to induction of dicentric chromosomes, is 110 min. In order to determine the correspondence of the results of in-vivo and in-vitro experiments 15 patients and their blood were irradiated with 60 C-γ-rays. No significant differences were measured. (AJ) [de

Studies on protective effects of superoxide dismutase on radiation induced-chromosomal aberrations

International Nuclear Information System (INIS)

Zheng Siying; Jiang Jiagui; Lin Xingcheng

1987-09-01

This study demonstrates that radiation induced-chromosomal aberrations are not only due to the direct effect of radiation h it , but the indirect effect of free radical as well. Therefore, chromosome damage induced by radiation may be reduced by adding exogenous SOD into the radiation exposed lymphocyte culture to eliminate the superoxide free radical which damages DNA. On the other hand, however, the radiosensitivity of lymphocytes can be raised by adding SOD inhibitor (DDC) into the lymphocyte culture, which makes radiation induced-chromosomal damages more severely

Studies on the chromosome aberrations and isozyme patterns in cancer patients treated with therapeutic radiation

International Nuclear Information System (INIS)

Kim, J.J.

1979-09-01

The chromosome aberration yield of peripheral blood lymphocytes obtained from cancer patients who had been locally irradiated with therapeutic radiation seems to be largely influenced by total dose, loss of cell with aberration, irradiation interval and dose per day. When treatment period from 7 to 21 days and total dose range from 1000 to 3000 rad, the aberration yield is considered to change according to total dose and accumulated effect by continued existence of damaged chromosomes. However, loss of cell with aberration might play important role in chromosome aberration yield of peripheral blood lymphocytes obtained from those who had received radiation above 3000 rad. In case that other conditions make little difference, dose per day and irradiation interval are looked upon as important factors in aberration yield of lymphocyte chromosomes

X-ray-induced chromosome aberrations in Down lymphocytes: an explanation of their increased sensitivity

International Nuclear Information System (INIS)

Preston, R.J.

1981-01-01

Unstimulated lymphocytes from individuals with Down Syndrome (trisomy 21) are more sensitive to the induction of dicentric and ring aberrations by X rays than normal lymphocytes. Several explanations involving the more rapid rejoining of X-ray--induced lesions in Down cells have been offered. It is shown here that the repair of the DNA damage converted into chromosome aberrations is more rapid in Down cells than normal cells. This more rapid repair results in a higher probability of producing chromosomes aberrations, and hence higher aberration frequencies in Down than normal cells

X-ray-induced chromosome aberrations in Down lymphocytes: an explanation of their increased sensitivity

International Nuclear Information System (INIS)

Preston, R.J.

1981-01-01

Unstimulated lymphocytes from individuals with Down Syndrome (trisomy 21) are more sensitive to the induction of dicentric and ring aberrations by X rays than normal lymphocytes. Several explanations involving the more rapid rejoining of X-ray-induced lesions in Down cells have been offered. It is shown here that the repair of the DNA damage converted into chromosome aberrations is more rapid in Down cells than normal cells. This more rapid repair results in a higher probability of producing chromosome aberrations, and hence higher aberration frequencies in Down than normal cells

Chromosomal integrity of freeze-dried mouse spermatozoa after 137Cs γ-ray irradiation

International Nuclear Information System (INIS)

Kusakabe, Hirokazu; Kamiguchi, Yujiroh

2004-01-01

This study demonstrated that freeze-dried mouse spermatozoa possess strong resistance to 137 Cs γ-ray irradiation at doses of up to 8 Gy. Freeze-dried mouse spermatozoa were rehydrated and injected into mouse oocytes with an intracytoplasmic sperm injection (ICSI) technique. Most oocytes can be activated after ICSI by using spermatozoa irradiated with γ-rays before and after freeze-drying. Sperm chromosome complements were analyzed at the first cleavage metaphase. Chromosome aberrations increased in a dose-dependent manner in the spermatozoa irradiated before freeze-drying. However, no increase in oocytes with chromosome aberrations was observed when fertilized by spermatozoa that had been irradiated after freeze-drying, as compared with freeze-dried spermatozoa that had not been irradiated. These results suggest that both the chromosomal integrity of freeze-dried spermatozoa, as well as their ability to activate oocytes, were protected from γ-ray irradiation at doses at which chromosomal damage is found to be strongly induced in spermatozoa suspended in solution

Induction of chromosomal aberrations by neutron capture reactions

International Nuclear Information System (INIS)

Ikushima, Takaji

1993-01-01

Boron neutron capture reaction (B-NCR) has been practiced in the treatment of malignancies of the central nervous system and melanoma using a thermal neutron beam from the KUR. Because of the very large neutron absorption cross-section and high kinetic energy released, gadolinium (Gd-157) has been expected to be an another promising element for neutron capture therapy. The dose-response relationship was determined for the induction of chromosomal aberrations by neutron capture reactions by B-10 and Gd-157 in cultured mammalian cells. The cells were exposed to thermal neutron beam with and without B-10 enriched (97 atom %) boric acid or Gd-DTPA, and chromosome-type aberrations were analysed in the first metaphases following irradiation. The frequency of dicentrics and rings increased linearly with neutron fluence either in the presence or absence of B-10 boric acid, while the yield of chromosomal aberrations induced by Gd-NCR increased in a linear quadratic fashion as a function of dose as in γ-rayed cells. Survival curves for the cells exposed to thermal neutrons showed no shoulder irrespective of the loading of B-10, but Gd-NCR produced the survival curve with a small shoulder. The differential chromosomal response to B-NCR and Gd-NCR might reflect the difference in radiation quality generated from the two types of thermal neutron capture reaction. (J.P.N.)

Chromosome aberrations of the peripheral lymphocytes in rabbits exposed to single and fractionated whole-body x-irradiations

International Nuclear Information System (INIS)

Tamura, Hiroaki; Sakurai, Masaharu; Sugahara, Tsutomu.

1978-01-01

The changes in the frequency of peripheral lymphocytes with chromosome aberrations were observed during or after irradiation of rabbits exposed to fractionated or single whole-body irradiations. In rabbits given daily fractionated whole-body irradiations the incidence of the aberrations showed a linear increase in the first week; however, the incidence decreased thereafter though exposures were repeated. The lymphocyte count tended to decrease as the number of irradiations increased. In rabbits exposed to a single dose of 250 R or 500 R the incidence of aberrations rapidly decreased over a period of 10 days following irradiation, and then showed a little change thereafter. The lymphocyte count in the peripheral blood reached a nadir 2 - 5 days after irradiation, and then started to increase gradually. It was speculated that there are two types of lymphocytes, long-lived and short-lived, in the peripheral blood of rabbits, both of which are PHA-committed. (auth.)

Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with 60Co

International Nuclear Information System (INIS)

Mendonca, Julyanne C.G.; Mendes, Mariana E.; Lima, Fabiana F.; Santos, Neide

2013-01-01

The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a 60 Co source at two different doses. Samples were obtained from a healthy donor and exposed to 60 Co source (Gammacel 220 ) located in the Department of Nuclear Energy of Pernambuco Federal University (DEN/UFPe/Brazil) with a rate of air Kerma to 3,277 Gy/h. Exposures resulted in absorbed dose 0.51 Gy and 0.77 Gy. Mitotic metaphases were obtained by culturing lymphocytes for chromosome analysis and the slides were stained with 5% Giemsa. Among the unstable chromosomal aberrations the dicentric chromosomes, ring chromosomes and acentric fragments were analyzed. To calculate the significance level the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. To calculate the significance level of the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. The results showed that there was significant difference of the frequencies of dicentric chromosomes (from 0.18 to 0.51 to 0.37 Gy to 0.77 Gy), however there was no statistically significant difference between the frequencies of acentric fragments ( 0.054 to 0, 51 Gy to 0.063 to 0.77 Gy) and ring chromosomes (0.001 to 0.51 Gy to 0.003 to 0.77 Gy). The low number of rings is found justified, considering that in irradiated human lymphocytes, its appearance is rare relative to dicentrics. The results confirm that dicentrics are the most reliable biomarkers in estimating dose after exposure to gamma radiation. These two points will make the calibration curve dose-response being built for Biological Dosimetry Laboratory of CRCN-NE/CNEN

Radiation-induced chromosomal instability

International Nuclear Information System (INIS)

Ritter, S.

1999-01-01

Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/μm) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

Comparative studies on radiation induced chromosome aberrations in the peripheral blood lymphocytes in primates

International Nuclear Information System (INIS)

Tobari, Izuo; Hirai, Momoki; Takahashi, Eiichi; Nakai, Sayaka; Utugi, Toyoko

1978-01-01

In order to obtain the information regarding interspesific extrapolation of the production of chromosome aberrations, we have examined species difference in the yields of dicentrics induced by the acute or chronic irradiations of gamma-rays. After acute irradiation, there were no significant differences in the yields among four primate species, man, crab-eating monkey, squirrel monkey and slow loris, in spite of the difference in chromosome arm number. On the other hand, after chronic irradiation, a significant difference in the yields was observed between man and crab-eating monkey. Comparing the α and β values estimated by fitting the observed yields with linear-quadratic equation, the value of β was clearly different between acute and chronic irradiations for both man and monkey. Furthermore, at low dose rate the value of β for monkey was almost negligible, while it was somewhat measurable one for man. To clarify the mechanism(s) involved in the species difference in the yields of dicentrics induced by chronic irradiation, post-irradiation incubation experiment was carried out. The considerable reductions of both the yields of dicentrics and mitotic indices during post-irradiation incubation periods under unstimulated conditions may probably indicate that cells with dicentrics are partly eliminated in the course of chronic irradiation for both man and monkey. However, the elimination mechanism is not sufficient to explain the reduction of dicentric yields after chronic irradiation. Consequently, Go repair mechanism(s) may presumably be responsible for the dose-rate effects, and the different amount of reduction of dicentric yields between man and monkey may reflect the different ability of Go repair between them. (author)

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblasts after alpha particle irradiation

Science.gov (United States)

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K.

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G2 phase premature chromosome condensation (G2-PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. mFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

The effects of exposure to different clastogens on the pattern of chromosomal aberrations detected by FISH whole chromosome painting in occupationally exposed individuals

International Nuclear Information System (INIS)

Beskid, O.; Dusek, Z.; Solansky, I.; Sram, R.J.

2006-01-01

The pattern of chromosomal aberrations (CA) was studied by fluorescence in situ hybridization (FISH) technique (whole chromosomes 1 and 4 painting) in workers occupationally exposed to any of the four following conditions: acrylonitrile (ACN), ethyl benzene (EB), carcinogenic polycyclic aromatic hydrocarbons (c-PAHs), and irradiation in nuclear power plants (NPP), respectively. Decrease in the relative frequency of translocations was observed in EB group, and an increase in reciprocal translocations in ACN and NPP-exposed groups. An increase in a relative number of insertions was registered under all four conditions (significant at ACN, EB, c-PAHs, quasisignificant at NPP-exposed groups). Significant differences in the percentage of lymphocytes with aberrations on chromosome 1 (58.8 ± 32.7%, versus 73.8 ± 33.6% in the controls, P G /100) increased with age (P G /100 (P < 0.05), but did not affect the pattern of chromosomal aberrations. Our results seem to indicate that different carcinogens may induce a different pattern of chromosomal aberrations

Relationship between chromosomal aberration of bone marrow cells and dosage of irradiation after 46Sc internal pollution and external low dose X-irradiation in mice

International Nuclear Information System (INIS)

Li Guofu; Li Zhang; Wu Yin

1989-01-01

The relationship between chromosomal aberration of bone marrow cells and dosage in mice 24 h after 46 Sc internal pollution combined with external low dose whole body X-irradiation was quantiatively studied. The results showed that the relationship between chromosomal aberration and dosage was expressed in a linear regression equation. The chromosomal aberration rate was lower in the combined exposure than that of the sum of internal and external exposures, but higher than that of either the internal or external exposure singly. The relationship between chromosomal aberration and time was expressed in the following three phase exponential function: Y(t) = 2.9078 exp 0.27668t + 2.9371 exp -0.0778t + 2.3786 -0.01788t . By means of fit test, there was no significant difference between the determined and the theoretical values. The 90% theoretical values got from all the equations distributed over the determined values

Origin of specific chromosome aberration in radiation-induced leukemia

International Nuclear Information System (INIS)

Ban, Nobuhiko; Kai, Michiaki; Masuno, Yoko

2005-01-01

The theme in the title is discussed from the four aspects of specific chromosome aberration (sAb) patterns in radiation-induced leukemia (RIL), possibility for radiation to induce the sAb in RIL, any evidence for participation of delayed aberration to form sAb and the proportion of such healthy humans as having the specifically rearranged genome. Data of sAb observed in leukemia of 25 A-bomb survivors and of 38 patients post radiotherapy of cancers give a rather common pattern. However, many inconsistent results are obtained for sAb in patients post radiotherapy, A-bomb survivors, residents living in radio-contaminated houses in Taipei, in vitro exposure, and Chernobyl residents. At present, any clear evidence is available neither for sAb derived from the delayed aberration nor for estimating the proportion with the specifically rearranged gene. As above, it is unlikely that radiation induces such a translocation abnormality as BCR-ABL specifically seen in leukemia, and this aspect will be important for studies on the genesis of RIL and its risk assessment. (S.I.)

Time course of photoreactivation of UV-induced chromosomal aberrations and lethal damage in interphase Xenopus cells

International Nuclear Information System (INIS)

Griggs, H.G.; Payne, J.D.

1981-01-01

Sets of G1, S, and G2 phase Xenopus cells were exposed to 15.0 Jm -2 UV and their ability to photoreactivate the induced cell killing and chromosomal aberrations was determined. Most of the lesions induced in G1 cells leading to cell death were converted to a non-photoreactivable state before the cells entered the S phase, while lesions leading to chromosomal aberrations were converted to a non-photoreactivable state as the cells entered the S phase. In S phase cells the UV-induced lesions leading to aberrations appeared to be converted to a non-photoreactivable state at a much faster rate than those leading to cell death. A significant fraction of the lesions induced in G2 cells, leading to cell death, were converted to a non-photoreactivable state before the progeny of the exposed cells reach the next S phase. Few, if any, lesions were induced in G2 cells that were expressed as aberrations at the first mitosis following exposure. The results suggest that the intracellular mechanism which expresses photoreactivable UV-induced lesions as cell death is not identical to the mechanism which expresses such lesions as chromosomal aberrations, and the two mechanisms operate with different efficiencies in different phases of the cell cycle. (author)

Chromosome Aberrations in Human Lymphocytes Irradiated with Ionizing Radiation

Energy Technology Data Exchange (ETDEWEB)

Ryu, Tae Ho; Kim, Jin Hong; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

The purpose of the present experiment was to provide data on the dose-dependent production of chromosome aberrations such as dicentrics, centric rings, and excess acentrics. Radiation is one of the more dangerous clastogens in the environment. Ionizing radiation causes chromosome breakages and various cytogenetic aberrations in exposed cells. In an investigation into radiation emergencies, it is important to estimate the dose to exposed persons for several reasons. Physical dosimeters (e. g., film badges) may misrepresent the actual radiation dose and may not be available in a radiological accident or terrorism incident. Biological dosimetry is suitable for estimating the radiation dose during such accidents. The dicentric chromosome assay is very sensitive and a reliable bio-indicator in cases of accidental overexposure.

The effect of 3-aminobenzamide on X-ray induction of chromosome aberrations in Down syndrome lymphocytes

International Nuclear Information System (INIS)

McLaren, R.A.; Au, W.W.; Legator, M.S.

1989-01-01

Human lymphocytes from normal and Down syndrome (DS) subjects were examined to determine the effect of 3-aminobenzamide (3AB) on X-ray-induced chromosome aberrations. Lymphocytes were treated with 150 or 300 rad of X-rays in the presence of 3 mM 3AB for various times after irradiation, and then the cells were analyzed for the presence of chromosome aberrations in mitotic cells. 3-Aminobenzamide had no effect on the frequency of chromosome aberrations as a result of treatment with X-rays in the presence of 3AB. These observations indicate that DS lymphocytes are more sensitive to the inhibition of poly(ADP)ribose synthetase than normal lymphocytes. (author). 44 refs.; 3 tabs

FREQUENCY OF CHROMOSOMAL ABERRATIONS AND MICRONUCLEI IN HORSE LYMPHOCYTES FOLLOWING IN VITRO EXPOSURE TO LOW DOSE IONISING RADIATION

Directory of Open Access Journals (Sweden)

Dunja Rukavina

2012-07-01

Full Text Available Ionising radiation is known to cause chromosomal instability, which is observed as increased frequency of chromosomal aberration and micronuclei. These are listed as reliable criteria in biological dosimetry. Numerous experiments conducted on both animal and plant models demonstrated that increase in radiation dosage is followed by increased mutation frequency, and that mutations occur even at the lowest exposure. We used horse blood in vitro irradiated by low doses of ionizing radiation. Cultivation of peripheral blood lymphocytes and micronucleus test were used as biomarkers of genetic damage. The observed aberrations were recorded and classified in accordance with the International System of Cytogenetic Nomenclature. Micronuclei were identified on the basis of criteria proposed by Fenech et al. (8. Analysis of chromosomal aberration showed increased frequency of aberrations in blood cultures exposed to 0,1 Gy and 0,2 Gy compared to the controls. Microscopic analysis of chromosomal damage in in vitro micronucleus test revealed that the applied radiation dose induced micronuclei while no binucleated cells with micronuclei were found in lymphocytes that were not irradiated. In this paper we analysed the influence of low dose ionising radiation on frequency of chromosomal aberration and micronuclei in horse lymphocytes following in vitro exposure to X-rays (0,1 Gy and 0,2 Gy. Key words: chromosomal aberrations, micronuclei, ionising radiation, horse lymphocytes

Cell inactivation and chromosomal aberrations induced by X-rays and fast neutrons in cells of the Chinese hamster. 1

International Nuclear Information System (INIS)

Tolkendorf, E.

1979-01-01

Asynchronously grown cultures of Chinese hamster cells V79-4 were irradiated in suspension with 180 kV X-rays and fast neutrons (average energy of 6.2 MeV). The damage was assessed by measuring cell survival and frequencies of chromosome aberrations in the first post-irradiation metaphases. The experimental data for survival and chromosome aberrations were fitted by computer programmes. From the fitted curves the relative biological effectiveness (RBE) of fast neutrons was calculated. The RBE shows a similar dose dependence for killed and aberrant cells. The RBE decreases with increasing dose and amounts to approximately 5 for both effects for small neutron doses. The highest RBE is found for asymmetrical chromosomal exchanges and is dependent on the neutron dose, too. However, for isochromatid deletions the RBE is dose independent with a value of 3.6. (author)

Molecular mechanisms involved in the production of chromosomal aberrations. I. Utilization of Neurospora endonuclease for the study of aberration production in G2 stage of the cell cycle

Energy Technology Data Exchange (ETDEWEB)

Natarajan, A T; Obe, G [Rijksuniversiteit Leiden (Netherlands). J.A. Cohen Inst. voor Radiopathologie en Stralingsbescherming

1978-10-01

Chinese hamster ovary cells (CHO) were X-irradiated in G2 stage of the cell cycle and immediately treated, in the presence of inactivated Sendai virus, with Neurospora endonuclease (E.C. 3.1.4.), an enzyme which is specific for cleaving single-stranded DNA. With this treatment, the frequencies of all types of chromosome aberrations increased when compared to X-irradiated controls. These results are interpreted as due to the conversion of some of the X-ray induced single-stranded DNA breaks into double-strand breaks by this enzyme. Similar enhancement due to this enzyme was found following treatment with methyl methanesulfonate (MMS) and bleomycin, but not following UV and mitomycin C. Addition of Micrococcus endonuclease and Neurospora endonuclease to the cells did not alter the frequencies of aberrations induced by UV. The introduction of enzymes with specific DNA-repair function offers possibilities to probe into the molecular events involved in the formation of structural chromosome aberrations induced by different classes of physical and chemical mutagens.

Chromosome aberrations in F1 from irradiated male mice studied by their synaptonemal complexes

International Nuclear Information System (INIS)

Kalikinskaya, E.I.; Kolomiets, O.L.; Shevchenko, V.A.; Bogdanov, Yu.F.

1986-01-01

Possible implications of surface-spread synaptonemal complex (SC) karyotyping in analysing the causes of sterility of F 1 from irradiated male mice are demonstrated in this work. After irradiation by 137 Cs γ-rays at a dose of 5 Gy the males were mated to unirradiated females and genetic analysis of fertility in the F 1 progeny was carried out. Males with abnormal fertility were examined for the presence of chromosome aberrations in diakinesis-metaphase I and in pachytene by the method of surface-spread SC karyotyping. In most cases, SC karyotyping provides additional information and permits the detection and analysis of aberrations that are not revealed in diakinesis. Two reciprocal translocations, one X autosomal and one nonreciprocal translocation were discovered in five F 1 males studied. It is concluded that the method is efficient in detecting translocations in pachytene in partially fertile F 1 hybrids of irradiated and normal mice. (orig.)

Polyploidy and chromosomal aberrations induced by mutagens in open flowering sterile mutants of spring barley

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Manzyuk, V T; Kozachenko, M R; Kirichenko, V V

1975-01-01

Two types of aberration in meiosis were observed which induced sterility in chemical and radiational mutations of spring wheat: asynapsis and absence of cytokinesis, and chromosomal aberrations in the form of bridges and fragments. Gamma-mutants have many more chromosomal aberrations in the form of fragments, bridges and cells with micronuclei than do chemical mutants. The percent of tetrads with micronuclei is 1.5-2 times greater than the number of dyads with such nuclei. We obtained an original gamma-mutant exhibiting depolyploidization and polyploidization in the mother cells; we also observed cells possessing chromosomal associations of n, 2n, 4n, 68, 8n and greater.

Methods of scoring induced chromosome structural changes in barley

International Nuclear Information System (INIS)

Nicoleff, H.; Gecheff, K.

1976-01-01

In barley, a material widely used in mutation and chromosomal aberration studies, the method most frequently used for scoring induced chromosomal changes is still anaphase analysis. In this paper, data obtained after treatment of barley with gamma-rays and ethyleneimine (EI) and comparative scoring of aberrations in metaphase and anaphase are reported and discussed. It is evident that the metaphase aberrations induced by gamma-rays and ethyleneimine, due probably to their specific location, showed a differential manifestation during anaphase. Thus, after treatment with ethyleneimine a great portion of the induced aberrations, being located preferentially at the centromere regions, gave no scorable bridges, and an apparent excess of fragments was observed at anaphase. After gamma-irradiation the differences between metaphase and anaphase scoring were mainly due to a large portion of fragments escaping detection

Chromosome aberrations: plants to human and Feulgen to FISH

International Nuclear Information System (INIS)

Natarajan, A.T.

2005-01-01

Chromosome aberrations and their impact on human health have been recognized for a long time. In the 1950s, in India, studies on induced chromosome aberrations in plants were initiated by Swaminathan and his students. I trace here the impact of these initial studies on further developments in this field. The studies which were started in plants have been extended to mammals (including human) and the simple squash and solid staining have been improved by molecular cytogenetic techniques, thus enabling accurate identification and quantification of different types of chromosome aberrations. These studies have also thrown light on the mechanisms of chromosome aberration formation, especially following exposure to ionizing radiation. (author)

Variation in sensitivity to #betta#-ray-induced chromosomal aberrations during the mitotic cycle of the sea urchin egg

International Nuclear Information System (INIS)

Ejima, Y.; Nakamura, I.; Shiroya, T.

1982-01-01

Sea urchin eggs were irradiated with 137 Cs #betta# rays at various stages of the mitotic cycle, and chromosomal aberrations at the first postirradiation mitosis and embryonic abnormalities at later developmental stages were examined. The radiosensitivity of the eggs to both endpoints varied in parallel with the mitotic stage at the time of irradiation, suggesting a possible relationship between chromosomal damage and embryonic abnormalities

Introduction of chromosome aberrations in mammalian cells after heavy ion exposure

International Nuclear Information System (INIS)

Ritter, S.; Kraft-Weyrather, W.; Scholz, M.; Kraft, G.

1991-01-01

The induction of chromosome aberrations by heavy charged particles was studied in V79 Chinese hamster cells over a wide range of energies (3-100 MeV/u) and LET (20-16000 keV/μm). For comparison, X-ray experiments were performed. Our data indicate quantitative and qualitative differences in the response of cells to particle and x-ray irradiation. For the same level of cell survival the amount of damaged cells which can be observed is smaller in heavy ion (11.4 MeV/u Ar) irradiated samples. The highest yield of damaged cells is found 8 to 12 hours after particle irradiation and 4 hours after x-irradiation. Differences in the amounts of damaged cells are attributed to cell cycle perturbations which interfere with the expression of damage. After heavy ion exposure the amount of cells reaching mitosis (mitotic index) decreases drastically and not all damaged cells reach mitosis with 48 hours after exposure. A portion of cells die in interphase. Cell cycle delays induced by x-ray irradiation are less pronounced and all cells reach the first post-irradiation mitosis within 24 hours after irradiation. Additionally, the damage produced by charged particles seems to be more severe. The disintegration of chromosomes was only observed after high LET radiation; an indication of the high and local energy deposition in the particle track. Only cross sections for the induction of chromosome aberrations in mitotic cells were reported in this paper because of the problems arising from the drastic cell cycle perturbations. In this case, cells were irradiated in mitosis and assayed immediately. (orig.)

Chromosome aberrations induced by radiation. With special reference to possible relation between chromosome aberrations and carcinogenesis

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Kamada, N [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1980-02-01

Chromosome aberration seems to be one of the most conspicuous residual abnormalities recognizable in radiation-exposed persons for many years after exposure. Knowledge of the biological significance of these abnormalities seems to be necessary for understanding of the effect of radiation on humans, especially in relation to possible leukemic development. Cytogenetic studies were performed on the bone marrow cells, T and B lymphocytes, and fibroblasts in atomic bomb-survivors who were in apparent good health (105 cases), atomic bomb exposed patients who had prolonged periods of blood disorders which terminated in acute leukemia (8 cases), and who had no such abnormalities (6 cases). All patients with chronic myelocytic leukemia (CML) and a history of atomic bomb exposure showed Philadelphia chromosome, a characteristic chromosome abnormality for CML. The persistent chromosome aberrations of bone marrow cells, T and B lymphocytes found among the atomic bomb survivors with or without blood disorders may give some clue to solve the problems of carcinogenesis.

Chromosome painting in biological dosimetry: Semi-automatic system to score stable chromosome aberrations

International Nuclear Information System (INIS)

Garcia-Sagredo, J.M.; Vallcorba, I.; Sanchez-Hombre, M.C.; Ferro, M.T.; San Roman Cos-Gayon, C.; Santos, A.; Malpica, N.; Ortiz, C.

1997-01-01

From the beginning of the description of the procedure of chromosome painting by fluorescence in situ hybridization (FISH), it was thought its possible application to score induced chromosomal aberrations in radiation exposition. With chromosome painting it is possible to detect changes between chromosomes that has been validated in radiation exposition. Translocation scoring by FISH, contrarily to the unstable dicentrics, mainly detect stable chromosome aberrations that do not disappear, it allows the capability of quantify delayed acute expositions or chronic cumulative expositions. The large number of cells that have to be analyzed for high accuracy, specially when dealing with low radiation doses, makes it almost imperative to use an automatic analysis system. After validate translocation scoring by FISH in our, we have evaluated the ability and sensitivity to detect chromosomal aberrations by chromosome using different paint probes used, showing that any combination of paint probes can be used to score induced chromosomal aberrations. Our group has developed a FISH analysis that is currently being adapted for translocation scoring analysis. It includes systematic error correction and internal control probes. The performance tests carried out show that 9,000 cells can be analyzed in 10 hr. using a Sparc 4/370. Although with a faster computer, a higher throughput is expected, for large population screening or very low radiation doses, this performance still has to be improved. (author)

Chromosome aberrations frequencies in peripheral blood lymphocytes from patients with larynx cancer

International Nuclear Information System (INIS)

Lisowska, H.; Lankoff, A.; Banasik, A.; Padjas, A.; Wieczorek, A.; Kuszewski, T.; Gozdz, A.; Wojcik, A.

2005-01-01

There is data suggesting that the sensitivity to ionising radiation of peripheral blood lymphocytes of cancer patients is higher than in healthy donors. This effect is especially prominent when chromosomal aberrations induced in S/G2 phase of the cell cycle are analysed. The aim of our study was to investigate if the S/G2- aberration frequencies in lymphocytes of patients with larynx cancer were higher than in control individuals. In addition, the multiple fixation regimen was applied in lymphocytes of the cancer patients. The aim of this was to check if the aberration frequencies scored in cells harvested at one time point were representative for a larger fraction of the cell cycle. Peripheral blood of 40 patients was collected before the onset of radiotherapy, cultured and irradiated with Co-60 (2 Gy) after 67 hours of culture time. Irradiation was performed in the Swietokrzyskie Oncology Center. Chromosome specimens were prepared from cells fixed at three time points after irradiation: 5, 7 and 9 hours. Colcemide was always added for 2 hours before harvest. Lymphocytes of 40 healthy donors were cultured and irradiated in the same way like in the case of patients with cancer, however, they were only harvested at one time point (5 hours p.r.). No statistically significant differences in aberration frequencies were observed between lymphocytes harvested at the 3 time points. In both donor groups, individual differences in aberration frequencies were observed. Despite this, the aberration frequencies in lymphocytes of patients were in average higher than in the healthy donors. This suggests, that the radiation sensitivity of lymphocytes of patients with larynx cancer may be a marker of cancer predisposition. More patients must be analysed to confirm this hypothesis. (author)

Relationship of DNA repair to chromosome aberrations, sister-chromatid exchanges and survival during liquid-holding recovery in X-irradiated mammalian cells

International Nuclear Information System (INIS)

Fornace, A.J. Jr.; Nagasawa, H.; Little, J.B.

1980-01-01

The repair of X-ray-induced DNA single strand breaks and DNA-protein cross-links was investigated in stationary phase, contact-inhibited mouse cells by the alkaline-elution technique. Approx. 90% of X-ray-induced single strand breaks were rejoined during the first hour of repair, whereas most of the remaining breaks were rejoined more slowly during the next 5 h. At early repair times, the number of residual non-rejoined sungle strand breaks was approx. proportional to the X-ray dose. DNA-protein cross-links were removed at a slower rate (Tsub(1/2) approx. 10-12 h). Cells were held in stationary growth for various periods of time after irradiation before subculture at low density to score for colony survival (potentially lethal damage repair), chromosome aberrations in the first mitosis, and sister-chromatid exchanges in the second mitosis. Both cell killing and the frequency of chromosome aberrations decreased during the first several hours of recovery, reaching a minimum level by 6 h; this decrease correlated temporally with the repair of the slowly rejoining DNA-strand breaks. Relatively few sister-chromatid exchanges were observed when the cells were subcultured immediately after X-ray. The exchange frequency rose to maximum levels after a 4-h recovery interval, and returned to control levels after 12 h of recovery. The possible relationship of DNA repair to these changes in survival, chromosome aberrations, and sister-chromatid exchanges during liquid-holding recovery is discussed. (orig.)

Application of conventional chromosomal aberration and fluorescence in-situ hybridisation translocation in the assessment of occupationally derived irradiation

International Nuclear Information System (INIS)

Samavat, H.; Seaward, M. R. D.; Gonzales, D. H.; Azizian, Gh.

2004-01-01

Background: Most of our current understanding of the biological effects of exposure to ionising radiation is based on conventional cytogenetic techniques, which enable our to determine the relationship between chromosomal aberration and dose received by radiation workers. However, conventional techniques have numerous limitations and chromosomal aberrations can be easily missed. Since fluorescence in situ hybridisation plays an important role in detecting chromosomal changes, this method was used to reassess data derived from previous studies employing conventional techniques. Materials and Methods: Two groups of radiographers were the subject of a study on conventional chromosomal aberration and fluorescence in situ hybridisation for translocation. The first group was chosen following an accidental contamination incident in a nuclear medicine department. The second group was composed of six radiographers working in an x-ray department with a previous record of overdose as recorded by film-badges; these workers had been the subjects of a previous chromosomal study. Coded blood samples from 11 radiographers and 11 controls were analysed for chromosomal aberration and by fluorescence in-situ hybridisation for translocation. 200 metaphases from the peripheral blood lymphocytes per subject were analysed to investigate possible frequencies of chromosome and chromatid type aberration and 2000 metaphases per subject were scored in fluorescence in-situ hybridisation method. Results: There was no significant difference between the radiographers and the control groups in conventional analysis; also there was no significant difference at the 95 % level of confidence in fluorescence in-situ hybridisation analysis. There was no correlation between levels of translocation and total lifetime doses from occupational ( according film-badge and TLD) and/or background irradiation. Conclusion: The overall conclusion is that the frequency of chromosomal damage in both groups of

Chromosome aberration assays in barley (Hordeum vulgare)

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Constantin, M J [Univ. of Tennessee, Knoxville; Nilan, R A

1982-01-01

Barley is an exceellent organism for studies of induced chromosome aberrations because of its few (2n = 2x = 14) relatively large chromosomes. Root-tip and shoot-tip cells have been used extensively for the study of ionizing radiation-induced chromosome aberrations. The general procedures are well known, the technology is simple and easy to learn, and the assays are relatively quick and inexpensive. Both root tips and shoot tips can be used for the study of chemical mutagens as well as ionizing radiations. Pollen mother cells are well suited for studying the effects of mutagens on meiotic chromosomes. The literature review for the Gene-Tox Program reported on 61 chemicals tested for their effects on barley chromosomes. Of these, 90% were reported to be either positive or positive dose-related, while 7% were negative and 3% were questionable. Barley assays based on chromosomal aberrations are useful to detect the clastogenic potency of chemicals under laboratory conditions. Indications are that the data from barley can be used to corroborate data obtained from other organisms. Among the classes of chemicals assayed were: alcohols and phenols; alkaloids; epoxides; alkyl sulfates; amides and sulfonamides; aromatic amines; aryl halides; aziridines; alkenes; carbamates; hydroazides; nitroaromatics; nitrosamides; nitrosources; phenothiazines; and polycyclic aromatic hydrocarbons.

Human hereditary diseases associated with elevated frequency of chromosome aberrations

International Nuclear Information System (INIS)

Ejima, Yosuke

1988-01-01

Human recessive diseases collectively known as chromosome breakage syndromes include Fanconi's anemia, Bloom's syndrome and ataxia telangiectasia. Cells from these patients show chromosome instabilities both spontaneously and following treatments with radiations or certain chemicals, where defects in DNA metabolisms are supposed to be involved. Cells from patients with ataxia telangiectasia are hypersensitive to ionizing radiations, though DNA replication is less affected than in normal cells. Chromatid-type as well as chromosom-type aberrations are induced in cells irradiated in G 0 or G 1 phases. These unusual responses to radiations may provide clues for understanding the link between DNA replicative response and cellular radiosensitivity. Alterations in cellular radiosensitivity or spontaneous chromosome instabilities are observed in some patients with congenital chromosome anomalies or dominant diseases, where underlying defects may be different from those in recessive diseases. (author)

Human hereditary diseases associated with elevated frequency of chromosome aberrations

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Ejima, Yosuke; Ikushima, Takaji (ed.)

1988-07-01

Human recessive diseases collectively known as chromosome breakage syndromes include Fanconi's anemia, Bloom's syndrome and ataxia telangiectasia. Cells from these patients show chromosome instabilities both spontaneously and following treatments with radiations or certain chemicals, where defects in DNA metabolisms are supposed to be involved. Cells from patients with ataxia telangiectasia are hypersensitive to ionizing radiations, though DNA replication is less affected than in normal cells. Chromatid-type as well as chromosom-type aberrations are induced in cells irradiated in G/sub 0/ or G/sub 1/ phases. These unusual responses to radiations may provide clues for understanding the link between DNA replicative response and cellular radiosensitivity. Alterations in cellular radiosensitivity or spontaneous chromosome instabilities are observed in some patients with congenital chromosome anomalies or dominant diseases, where underlying defects may be different from those in recessive diseases.

Modulation of gamma ray induced chromosome aberrations in human peripheral blood lymphocytes by Hippophae rhammnoides leaf extract, SBL-1

International Nuclear Information System (INIS)

Tyagi, Anuradha; Madhu Bala

2014-01-01

Hippophae rhammnoides L. commonly known as seabuckthorn is a temperate shrub and native of Asia and Europe. It has high antioxidant potential and is known to the traditional Indian, Chinese and Tibetan medicinal system for treatment of multiple disorders viz., circulatory and digestive disorders, hepatic injuries, neoplasia etc. One time treatment with the standardized leaf extract from H. rhammnoides (SBL-1) before whole body irradiation with 60 Co (10 Gy), rendered more than 90% survival in non SBL-1 treated irradiated animals (J herbs, spices medi plants, 2009). Present study investigated the effects of SBL-1 treatment on chromosomal damage in human peripheral blood lymphocytes (PBL), with or without 60 Co-gamma-radiation. The lymphocytes were isolated from the blood drawn from different donors. The isolated lymphocytes were divided into several groups: Group 1-untreated control, Group 2-irradiated (2 Gy), Group 3, 4 and 5 were treated with different concentration of SBL-1, 30 min. after irradiation with 60 Co-gamma-rays (2 Gy). Group 6 was treated with the maximum concentration of SBL-1 used in the study. The metaphase spreading technique was used as per standard procedure to record chromosome breaks, dicentrics, acentrics and rings. The results were also recorded in terms of total aberrant metaphase and frequency of aberrant metaphase per 100 cells. In comparison to the untreated control, in the irradiated PBL culture, there was 8-fold increase in breaks, 211-folds in dicentrics, 75-folds in acentrics and 3-folds in rings (average data). SBL-1 alone at the highest concentration did not cause any significant change in number of breaks, dicentrics, acentrics and rings. The radiation induced aberrations decreased significantly by treatment with SBL-1 and the maximum decrease was observed when the cells were treated with 22μg/ml of SBL-1. These results demonstrated the anti-clastogenic activity of SBL-1 against gamma radiation induced damage. (author)

Diagnostic radiation and chromosome aberrations

International Nuclear Information System (INIS)

Patil, S.R.; Hecht, F.; Lubs, H.A.; Kimberling, W.; Brown, J.; Gerald, P.S.; Summitt, R.L.

1977-01-01

Some evidence is presented suggesting that diagnostic X-rays may be important in the origin of a new chromosomal abnormality other than Down syndrome. Chromosome analyses have been carried out on 4342 children, seven or eight years old. Maternal diagnostic irradiation in the year before conception and up to third lunar month of the index pregnancy was recorded, before the chromosome study began, together with a large amount of family and clinical data. Information on X-ray exposure was supplied by the mothers, s o radiation dosage could not be estimated. 21 children (including a pair of twins and a pair of siblings) born to 19 mothers had chromosomal aberrations. The mothers of six children with inherited translocations, rearrangements and XYY karyotypes were excluded, and 3 (23%) of the remaining 13 mothers had received abdominal and pelvic X-ray exposures. In the whole sample, however, only 6% of the mothers had diagnostic irradiation. Two of these mothers, aged sixteen and twenty, gave birth to a child each with de-novo autosomal translocations, and the third mother, aged thirty-two, had a child with a complex mosaicism involving one X chromosome. Although the sample size of the mothers with chromosomally abnormal children is small, the results are significant. (U.K.)

Diagnostic radiation and chromosome aberrations

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Patil, S R; Hecht, F [Dept. of Pediatrics, Child Development and Rehabilitation Center, Univ. of Oregon Health Sciences Center, Portland, Oregon (USA); Lubs, H A; Kimberling, W; Brown, J; Gerald, P S; Summitt, R L

1977-01-15

Some evidence is presented suggesting that diagnostic X-rays may be important in the origin of a new chromosomal abnormality other than Down syndrome. Chromosome analyses have been carried out on 4342 children, seven or eight years old. Maternal diagnostic irradiation in the year before conception and up to third lunar month of the index pregnancy was recorded, before the chromosome study began, together with a large amount of family and clinical data. Information on X-ray exposure was supplied by the mothers, so radiation dosage could not be estimated. 21 children (including a pair of twins and a pair of siblings) born to 19 mothers had chromosomal aberrations. The mothers of six children with inherited translocations, rearrangements and XYY karyotypes were excluded, and 3 (23%) of the remaining 13 mothers had received abdominal and pelvic X-ray exposures. In the whole sample, however, only 6% of the mothers had diagnostic irradiation. Two of these mothers, aged sixteen and twenty, gave birth to a child each with de-novo autosomal translocations, and the third mother, aged thirty-two, had a child with a complex mosaicism involving one X chromosome. Although the sample size of the mothers with chromosomally abnormal children is small, the results are significant.

Frequencies of chromosomal aberrations and sister chromatid exchanges in the benthic worm Neanthes arenaceodentata exposed to ionizing radiation

International Nuclear Information System (INIS)

Harrison, F.L.; Rice, D.W. Jr.; Moore, D.H.

1984-07-01

Traditional bioassays are unsuitable for assessing sublethal effects from ocean disposal of low-level radioactive waste because mortality and phenotypic responses are not anticipated. We compared the usefulness of chromosomal aberration and sister chromatid exchange (SCE) induction as measures of low-level radiation effects in a sediment-dwelling marine worm, Neanthes arenaceodentata. The SCEs, in contrast to chromosomal aberrations, do not alter the overall chromosome morphology and in mammalian cells appear to be a more sensitive indicator of DNA alterations caused by environmental mutagens. Newly hatched larvae were exposed to two radiation-exposure regimes of either x rays at a high dose rate of 0.7 Gy (70 rad)/min for as long as 5.5 min or to 60 Co gamma rays at a low dose rate of from 4.8 x 10 -5 to 1.2 x 10 -1 Gy (0.0048 to 12 rad)/h for 24 h. After irradiation, the larvae were exposed to 3 x 10 -5 M bromodeoxyuridine (BrdUrd) for 28 h (x-ray-irradiated larvae) or for 54 h ( 60 Co-irradiated larvae). Larval cells were examined for the proportion of cells in first, second, and third or greater division. Frequencies of chromosomal aberrations and SCEs were determined in first and second division cells, respectively. Results from x-ray irradiation indicated that dose-related increases occur in chromosome and chromatid deletions, but a dose of equal or greater 2 Gy (equal to or greater than 200 rad) was required to observe a significant increase. Worm larvae receiving 60 Co irradiation showed elevated SCE frequencies with a significant increase of 0.6 Gy (60 rad). We suggest that both SCEs and chromosomal aberrations may be useful for measuring effects on genetic material induced by radiation. 56 references, 7 figures, 9 tables

Frequencies of X-ray induced chromosome aberrations in lymphocytes of xeroderma pigmentosum and Fanconi anemia patients estimated by Giemsa and fluorescence in situ hybridization staining techniques

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Saraswathy Radha

2000-01-01

Full Text Available Blood lymphocytes from xeroderma pigmentosum (XP and Fanconi anemia (FA patients were assessed for their sensitivity to ionizing radiation by estimating the frequency of X-ray (1 and 2 Gy-induced chromosome aberrations (CA. The frequencies of aberrations in the whole genome were estimated in Giemsa-stained preparations of lymphocytes irradiated at G0 or G2 stages. The frequencies of translocations and dicentrics involving chromosomes 1 and 3 as well as the X-chromosome were determined in slides stained by fluorescence in situ hybridization (FISH technique. An increase in all types of CA was observed in XP and FA lymphocytes irradiated at G0 when compared to controls. The frequency of dicentrics and rings was 6 to 27% higher (at 1 and 2 Gy in XP lymphocytes and 37% higher (at 2 Gy in FA lymphocytes than in controls, while chromosome deletions were higher in irradiated (30% in 1 Gy and 72% in 2 Gy than in control XP lymphocytes and 28 to 102% higher in FA lymphocytes. In G2-irradiated lymphocytes the frequency of CA was 24 to 55% higher in XP lymphocytes than in controls. In most cases the translocation frequencies were higher than the frequencies of dicentrics (21/19.

'BioQuaRT' project: design of a novel in situ protocol for the simultaneous visualisation of chromosomal aberrations and micronuclei after irradiation at microbeam facilities

International Nuclear Information System (INIS)

Patrono, C.; Testa, A.; Monteiro Gil, O.; Giesen, U.; Langner, F.; Rabus, H.; Pinto, M.

2015-01-01

The aim of the 'BioQuaRT' (Biologically weighted Quantities in Radiotherapy) project is to develop measurement techniques for characterising charged particle track structure on different length scales, and to correlate at the cellular level the track structure properties with the biological effects of radiation. This multi-scale approach will allow characterisation of the radiation qualities used in radiotherapy and the related biological effects. Charged-particle microbeam facilities were chosen as the platforms for all radiobiology experiments in the 'BioQuaRT' project, because they allow targeting single cells (or compartments of a cell) with a predefined number of ionising particles and correlating the cell-by-cell induced damage with type and energy of the radiation and with the number of ions per cell. Within this project, a novel in situ protocol was developed for the analysis of the mis-repaired and/or unrepaired chromosome damage induced by charged-particle irradiations at the Physikalisch-Technische Bundesanstalt (PTB) ion microbeam facility. Among the cytogenetic biomarkers to detect and estimate radiation-induced DNA damage in radiobiology, chromosomal aberrations and micronuclei were chosen. The characteristics of the PTB irradiation system required the design of a special in situ assay: specific irradiation dishes with a base made from a bio-foil 25-μm thick and only 3000-4000 cells seeded and irradiated per dish. This method was developed on Chinese hamster ovary (CHO) cells, one of the most commonly used cell lines in radiobiology in vitro experiments. The present protocol allows the simultaneous scoring of chromosome aberrations and micronuclei on the same irradiated dish. Thanks to its versatility, this method could also be extended to other radiobiological applications besides the single-ion microbeam irradiations. (authors)

Protective effect of Yin Shen Yin on chromosome aberrations in peripheral blood in dogs induced by γ-ray irradiation

International Nuclear Information System (INIS)

Zhu Bingchai; Chen Tiehe; Lu Jiaben; Wang Zongwu; Huang Yinmei

1992-01-01

'Yin Shen Yin' preparation used in this studies is made up of Tremella Fcuiformis, Radix Acanthopanacis Senticosi and others. The drug was taken orally to dogs before irradiation, and the same time, its anti-radiation effect was compared with those of Tremella Fuciformis and cystamine. The results showed that 'Yin Shen Yin', Tremella and cystamine all have not obvious harmful effects on chromosome, however, they have good protective effects on chromosome damage induced by γ-ray irradiation. Among them, high dose 'Yin Shen Yin' has the best radio-protective effect

Analysis of α-particle induced incomplete chromosome aberrations, using pan-centro metric and pan-telomeric DNA probes

International Nuclear Information System (INIS)

Mestres, M.; Schmid, E.; Stephan, G.; Barrios, L.; Caballin, M. R.; Barquinero, J. F.

2004-01-01

The aim of the present study has been the evaluation of the incompleteness of α-particle induced chromosome aberrations by the simultaneous detection of all centromeres and telomeres present in human lymphocytes. For this purpose attached lymphocytes were irradiated at doses of 0.2, 0.5,0.7 and 1 Gy in a ''241Am source. FISH techniques were applied using pan-centromeric and pan-telomeric probes. All abnormal cells were digitalised and analysed using a Cytovision FISH workstation. A total of 378 incomplete chromosomes plus incomplete acentrics was found. Cases with more than 92 telomeres were not detected. The ratio between total incomplete elements and multicentrics was 1.00. The total number of acentric fragments was 822; 57% of then were complete fragments ace (+.+), 26% incomplete fragments ace (+,-), and 17% interstitial fragment ace (-.-). The percentage of incomplete aberrations is higher after high-LET than described for low-LET exposure. The results seem to indicate that compared to low-LET. after α-particle exposure it is more likely to repair the centromere-containing elements. (Author) 30 refs

Chromosome aberrations in space-exposed seeds of Allium cepa L

International Nuclear Information System (INIS)

Wang, S.

1994-01-01

Onion (Allium cepa L.) seeds c.v. Patti King were packed in sealed canisters and launched into space orbit about 296 km above earth by the space shuttle Challenger in April 1984. After more than five years exposure to space, the seeds were retrieved by the space shuttle Columbia and returned to earth in January, 1990. Somatic chromosomes at anaphase and telophase stages were analyzed and cells with normal or abnormal chromosome separations were recorded. Space-exposed and control seeds showed an average of 10.9% and 2.8% chromosome aberrations, respectively. Seeds contained in the two exterior layers of the canister had 16.5 to 18.5% chromosome aberration. The results indicated that irradiation in space would be a direct cause for chromosome aberrations in onion seeds. Analysis of seed germination rate and vigor were also determined. The average germination rate for space-exposed and control seeds were 53.3% and 19.8%, respectively. Possible reasons for the results obtained are discussed [it

Use of unstable chromosome aberrations for biological dosimetry after the first postirradiation mitosis

International Nuclear Information System (INIS)

Doloy, M.T.; Malarbet, J.L.; Guedeney, G.; Bourguignon, M.; Leroy, A.; Reillaudou, M.; Masse, R.

1991-01-01

The loss of unstable chromosome aberrations after the first postirradiation mitosis makes their use difficult in radiation dosimetry. We describe here a method which, in a cell population observed at this stage, allows retrospective estimation of the frequencies of the unstable aberrations induced at the time of irradiation, and their use as a dosimeter. The laws controlling the behavior of unstable aberrations during mitosis were defined from a large-scale experiment on irradiated human lymphocytes. For cells undergoing the first, second, or third mitosis after irradiation, relationships were determined between the frequency, at irradiation time, of acentric fragments not arising from formation of dicentrics or rings, and the ratio of dicentrics and centric rings appearing without acentric fragments to the total number of dicentrics plus rings. On the basis of this ratio, the method described here provides an assessment of the postirradiation mitotic activity in a cell population. This assessment permitted estimation of the cell distribution and frequency of dicentrics plus centric rings, and of the frequency of acentric fragments at the time of irradiation. The use of this method for retrospective dosimetry after whole-body irradiation under various conditions of exposure is illustrated

Distribution of X-ray induced chromosome rearrangement breaks along the polytene chromosomes of Anopheles messeae

International Nuclear Information System (INIS)

Pleshkova, G.N.

1983-01-01

Distribution of chromosomal aberrations localization along polytene chromosomes (aoutosomes) of salivary glands of malarial mosquito. Anopheles messeae is presented. Induced aberrations in F 1 posterity from X-ray irradiated fecundated females are studied. Poipts of breaks of inversions and trapslocations are localized separately. There are no considerable dif-- ferences in the distribution character of two types of aberrations. Over the length of autosomes the breaks are more frequent in distal halves, their frequency in proximal parts anally in near centromeric regions of chromosomes is reduced. Concentration of breaks in certain ''hot points'' of the chromosomes is pointed out. Comparison of distribution of actual and expected frequencies of break points according to chi 2 criterion revealed highly fiducial discrepancies, testifying to uneven participation of different regions of chromosomes in aberration formation. Similarities and differences of the data obtained from analogous ones, demonstrated in Drosophila, as well as possible reasons for the distribution unevennes are discussed. On the basis of analysis of intrinsic and literature data a supposition is made that the ''hot points'' (break concentrations) can be considered as localizaion markers of intercalary heterochromatin

Persistence of X-ray-induced chromosomal rearrangements in long-term cultures of human diploid fibroblasts

International Nuclear Information System (INIS)

Kano, Y.; Little, J.B.

1984-01-01

As part of a long-term study of mechanisms of human cell neoplastic transformation, the authors have examined the change in the frequencies of X-ray-induced chromosome rearrangements in density-inhibited human foreskin fibroblasts as a function of subculture time. In nonproliferating cells, the frequency of chromosomal aberrations declined within 24 to 48 hr but still remained at a relatively high level up to 43 days after irradiation. Aberrations disappeared rapidly, however, when the cells were allowed to proliferate, indicating that these lesions are lethal to dividing cells. The frequency of induced translocations, as determined by analysis of G-banded karyotypes, was dose dependent and remained stable up to 20 mean population doublings after irradiation. When subculture of density-inhibited cultures was delayed for 4 hr after irradiation (confluent holding), the frequency of chromosomal aberrations in the first mitosis declined, whereas the translocation frequencies at later passage were elevated as compared with cells subcultured immediately. This correlates with the reported increase in the frequency of transformation under similar conditions. These findings support the hypothesis that chromosomal rearrangements induced by DNA damage may be involved in the initiation of cancer

Simulations of DSB Yields and Radiation-induced Chromosomal Aberrations in Human Cells Based on the Stochastic Track Structure Induced by HZE Particles

Science.gov (United States)

Ponomarev, Artem; Plante, Ianik; George, Kerry; Wu, Honglu

2014-01-01

The formation of double-strand breaks (DSBs) and chromosomal aberrations (CAs) is of great importance in radiation research and, specifically, in space applications. We are presenting a new particle track and DNA damage model, in which the particle stochastic track structure is combined with the random walk (RW) structure of chromosomes in a cell nucleus. The motivation for this effort stems from the fact that the model with the RW chromosomes, NASARTI (NASA radiation track image) previously relied on amorphous track structure, while the stochastic track structure model RITRACKS (Relativistic Ion Tracks) was focused on more microscopic targets than the entire genome. We have combined chromosomes simulated by RWs with stochastic track structure, which uses nanoscopic dose calculations performed with the Monte-Carlo simulation by RITRACKS in a voxelized space. The new simulations produce the number of DSBs as function of dose and particle fluence for high-energy particles, including iron, carbon and protons, using voxels of 20 nm dimension. The combined model also calculates yields of radiation-induced CAs and unrejoined chromosome breaks in normal and repair deficient cells. The joined computational model is calibrated using the relative frequencies and distributions of chromosomal aberrations reported in the literature. The model considers fractionated deposition of energy to approximate dose rates of the space flight environment. The joined model also predicts of the yields and sizes of translocations, dicentrics, rings, and more complex-type aberrations formed in the G0/G1 cell cycle phase during the first cell division after irradiation. We found that the main advantage of the joined model is our ability to simulate small doses: 0.05-0.5 Gy. At such low doses, the stochastic track structure proved to be indispensable, as the action of individual delta-rays becomes more important.

The yield of fission neutron-induced chromatid aberrations in G[sub 2]-stage human lymphocytes: effect of caffeine, hydroxyurea and cytosine arabinoside post-irradiation

Energy Technology Data Exchange (ETDEWEB)

Antoccia, A.; Tanzarella, C. (La Sapienza Univ., Rome (Italy)); Palitti, F. (Tuscia Univ., Viterbo (Italy) La Sapienza Univ., Rome (Italy)); Raggi, T. (Tuscia Univ., Viterbo (Italy)); Catena, C. (ENEA, Casaccia (Italy). Centro Ricerche Energia)

1992-11-01

To evaluate the influence of inhibitors of DNA synthesis/repair on the yield of chromosomal aberrations in the G[sub 2] phase of the cell cycle, whole-blood cultures of human lymphocytes were exposed to various doses of fission neutrons or X-rays and treated post-irradiation during the last 2.45 h before harvesting, with 5mM hydroxyurea (HU) and 0.05 mM cytosine arabinoside (ara-C). The presence of caffeine and HU strongly potentiated the yield of chromatid-type aberrations induced by both neutrons and X-rays. No potentiating effect, except at the highest dose of neutrons, was observed when irradiated cells were subsequently treated with ara-C. In addition, neutron-induced mitotic delay was shortened by treatment with caffeine, mainly within the first 2 h after irradiation. (Author).

Heavy ion-induced chromosomal aberrations analyzed by fluorescence in situ hybridization

International Nuclear Information System (INIS)

Durante, M.; Gialanella, G.; Grossi, G.; Pugliese, M.; Cella, L.; Greco, O.; George, K.; Yang, T.C.

1997-01-01

We have investigated the effectiveness of heavy ions in the induction of chromosomal aberrations in mammalian cells by the recent technique of fluorescence in situ hybridization (FISH) with whole-chromosome probes. FISH-painting was used both in metaphase and interphase (prematurely condensed) chromosomes. The purpose of our experiments was to address the following problems: (a) the ratio of different types of aberrations as a function of radiation quality (search for biomarkers); (b) the ratio between aberrations scored in interphase and metaphase as a function of radiation quality (role of apoptosis); (c) differences between cytogenetic effects produced by different ions at the same LET (role of track structure). (orig./MG)

Heavy ion-induced chromosomal aberrations analyzed by fluorescence in situ hybridization

Energy Technology Data Exchange (ETDEWEB)

Durante, M; Gialanella, G; Grossi, G; Pugliese, M [Univ. ` ` Federico II` ` , Naples (Italy). Dept. of Physics; [INFN, Naples (Italy); Cella, L; Greco, O [Univ. ` ` Federico II` ` , Naples (Italy). Dept. of Physics; Furusawa, Y [NIRS, Chiba (Japan); George, K; Yang, T C [NASA Lyndon B. Johnson Space Center, Houston, TX (United States)

1997-09-01

We have investigated the effectiveness of heavy ions in the induction of chromosomal aberrations in mammalian cells by the recent technique of fluorescence in situ hybridization (FISH) with whole-chromosome probes. FISH-painting was used both in metaphase and interphase (prematurely condensed) chromosomes. The purpose of our experiments was to address the following problems: (a) the ratio of different types of aberrations as a function of radiation quality (search for biomarkers); (b) the ratio between aberrations scored in interphase and metaphase as a function of radiation quality (role of apoptosis); (c) differences between cytogenetic effects produced by different ions at the same LET (role of track structure). (orig./MG)

Survivin and chromosome instability induced by X-irradiation

International Nuclear Information System (INIS)

Shen Bo; Ju Guizhi; Liu Yang

2006-01-01

Objective: To explore the biological effect of survivin on chromosome instability induced by X-ray irradiation. Methods: Immunocytochemistry was used to detect the expression of sutvivin in HeLa cells. Carrier pSUPER-SVV was transfected into HeLa cells to interfere the expression of survivin. Flow cytometry assay was applied to detect the occurrence of polyploid at 0 h, 4 h, 12 h, and 48 h after the HeLa cells transfected with pSUPER-SVV and irradiated with 4 Gy X-rays irradiation, and compared with the group irradiated with 4 Gy X-rays but no transfection. Results: The expression of survivin was down-regulated by transfecting with small hair RNA, its depression rate was estimated to be about 32.16% at 48 h after transfection. The occurrence of polyploid giant cells was higher in the 4 Gy X-ray irradiated group at 48 h after the irradiation than the control groups (P<0.001). Being expression of survivin interfered, the occurrence at 12 h or 48 h after irradiation, however, was about two times higher than that in the control group. Conclusion: X-ray irradiation can induce chromosome instability in HeLa cells and the effect could be enhanced by interfering the expression of surviving. It was suggested that survivin plays an important role in maintaining the stability of chromosome. (authors)

Effects of aphidicolin on repair replication and induced chromosomal aberrations in mammalian cells

International Nuclear Information System (INIS)

Zeeland, A.A. van; Filon, A.R.; Natarajan, A.T.; Bussmann, C.J.M.; Degrassi, F.; Kesteren-van Leeuwen, A.C. van; Palitti, F.; Rome Univ.

1982-01-01

The influence of aphidicolin, an inhibitor of polymerase α, on UV-induced repair replication in human skin fibroblasts, as well as in HeLa cells, was determined. In growing fibroblasts and in HeLa cells, aphidicolin had a potentiating effect on UV-induced repair replication, whereas in fibroblasts grown to confluency, aphidicolin had an inhibitory effect. This inhibitory effect was stronger when measured in the presence of hydroxyurea. In HeLa cells the presence of both aphidicolin and hydroxyurea also had an inhibitory effect, but in the presence of hydroxyurea alone, UV-induced repair replication was enhanced. The results of these studies can be explained on the basis of differences in deoxyribonucleotide triphosphate pool sizes in growing and confluent cells. Post-treatment of X-irradiated human lymphocytes in the G 0 and G 1 stages with aphidicolin increased the frequencies of X-ray-induced chromosomal aberrations. Such an increase was not observed in G 1 cells of CHO after similar treatment with X-rays and aphidicolin. However, treatment with aphidicolin, in the G 2 stage, increased the frequencies of induced chromatid breaks. The significance of these results is discussed. (orig.)

Intrachromosomal exchange aberrations predicted on the basis of globular interphase chromosome model

International Nuclear Information System (INIS)

Andreev, S.G.; Eidelman, Yu.A.

2002-01-01

One of the key questions in understanding mechanisms of chromosome aberration production is how does interphase chromosome structure affect aberration formation. To explore this a modelling approach is presented which combines Monte Carlo simulation of both a particle track and interphase chromosome structure. The structural state of interphase chromosome influences a dose-effect relationship for intrachromosomal exchange aberrations (intrachanges). It is shown that intrachanges are induced frequently by both X rays and a particles if the chromosome is in the condensed globular but not in the decondensed coiled state. Truly simple intra-arm intrachanges induced by X rays are dose squared in coiled chromosomes, but exhibit linear dose dependence in globular chromosomes. Experimental data on interarm intrachanges obtained by dual arm chromosome painting are analysed by means of the technique presented. Results of analysis support the conclusion about the arms proximity of chromosome 1 in human lymphocytes. (author)

The distribution of chromosome aberrations among chromosomes of karyotype in exposed human lymphocyte

International Nuclear Information System (INIS)

Que Tran; Tien Hoang Hung

1997-01-01

Induced chromosome aberrations (ch. ab.) in exposed Human peripheral blood lymphocyte have been used to assay radio.bio.doses, because of their characters such as: the maintaining Go phase in cell cycle in body, the distribution of cell in blood system and the distribution of ch. ab. in exposed cells of body and among chromosomes of karyotype. The frequency of ch. ab. reflected the quantity of radiation dose, dose rate and radiation energy. The dependence between radiation dose and frequency of ch. ab. was illustrated by the mathematic equations. The distribution of induced ch. ab. among the cells exposed to uniform radiation fields was Poisson's, but the distribution of ch. ab. among chromosomes in karyotype depended on radiation field and mononucleotid sequence of DNA molecular of each chromosome. The minimum influence of mononucleotid sequence of DNA molecular in inform ch. ab. will be advantageous state for dose-assessments. The location of induced ch. ab. in exposed Human lymphocyte had been determined by karyotype analyses. The data of statistic analyse had improved that the number of ch. ab. depended on the size of chromosomes in karyotype. The equal distribution of ch. ab.among chromosomes in karyotype provided the objectiveness and the accuracy of using the chromosomal aberrant analysis technique on bio-dosimetry. (author)

Survival and transmission of symmetrical chromosomal aberrations

International Nuclear Information System (INIS)

Savage, J.R.K.

1979-01-01

The interaction between the lesions to produce chromosomal structural changes may be either asymmetrical (A) or symmetrical (S). In A, one or more acentric fragments are always produced, and there may also be the mechanical separation problems resulting from bridges at anaphase, while S-changes never produce fragment, and pose no mechanical problem in cell division. If A and S events occur with equal frequency, it might be an indication that they are truly the alternative modes of lesion interaction. Unstimulated lymphocytes were irradiated with 2.68 Gy 250 kV X-ray, and metaphases were sampled at 50 h after the stimulation. Preparations were complete diploid cells, and any obvious second division cells were rejected. So far as dermal repair and fibroblast functions are concerned, aberration burden seems to have little consequence from the view-point of the long-term survival in vivo. Large numbers of aberrations (mainly S translocation and terminal deletion) were found in the samples taken up to 60 years after therapy. Skin biopsies were removed 1 day and 6 months after irradiation and cultured. In irradiated cells, reciprocal translocations dominated, followed by terminal deletions, then inversions, while no chromosome-type aberration was seen in the control cells. a) The relative occurrence of A : S changes, b) long-term survival in vivo, c) the possibility of in vivo repair, and d) some unusual features of translocation found in Syrian hamsters are reviewed. The relevance or importance of major S events is clearly dependent upon the cells, the tissues or the organisms in which they occur. (Yamashita, S.)

No increase in radiation-induced chromosome aberration complexity detected by m-FISH after culture in the presence of 5'-bromodeoxyuridine

International Nuclear Information System (INIS)

Sumption, Natalia D.; Goodhead, Dudley T.; Anderson, Rhona M.

2006-01-01

The thymidine analogue, 5'-bromodeoxyuridine (BrdU), is a known mutagen that is routinely introduced into culture media for subsequent Harlequin stain analysis and determination of cell cycle status. Previously, we examined the induction of chromosome aberrations in human peripheral blood lymphocytes (PBL) known to be in their 1st cell division following exposure to a low dose (0.5 Gy, average one α-particle per cell) of high-LET α-particles. We found complex chromosome aberrations to be characteristic of exposure to high-LET radiation and suggested the features of complex exchange to reflect qualitatively the spatial deposition of this densely ionising radiation. To exclude the possibility that BrdU addition post-irradiation influenced the complexity of chromosomal damage observed by m-FISH, the effect of increasing BrdU concentration on aberration complexity was investigated. Comparisons between BrdU concentration (0, 10 and 40 μM) and between sham- and α-particle-irradiated PBL, were made both independently and in combination to enable discrimination between BrdU and high-LET radiation effects. Aberration type, size, complexity and completeness were assessed by m-FISH, and the relative progression through cell division was evaluated. We found no evidence of any qualitative difference in the complexity of damage as visualised by m-FISH but did observe an increase in the frequency of complex exchanges with increasing BrdU concentration indicative of altered cell cycle kinetics. The parameters measured here are consistent with findings from previous in vitro and in vivo work, indicating that each complex aberration visualised by m-FISH is characteristic of the structure of the high-LET α-particle track and the geometry of cell irradiated

Non-random intrachromosomal distribution of radiation-induced chromatid aberrations in Vicia faba. [Aberration clustering

Energy Technology Data Exchange (ETDEWEB)

Schubert, I; Rieger, R [Akademie der Wissenschaften der DDR, Gatersleben. Zentralinst. fuer Genetik und Kulturpflanzenforschung

1976-04-01

A reconstructed karyotype of Vicia faba, with all chromosomes individually distinguishable, was treated with X-rays, fast neutrons, (/sup 3/H) uridine (/sup 3/HU). The distribution within metaphase chromosomes of induced chromatid aberrations was non-random for all agents used. Aberration clustering, in part agent specific, occurred in chromosome segments containing heterochromatin as defined by the presence of G bands. The pattern of aberration clustering found after treatment with /sup 3/HU did not allow the recognition of chromosome regions active in transcription during treatment. Furthermore, it was impossible to obtain unambiguous indications of the presence of AT- and GC-base clusters from the patterns of /sup 3/HT- and /sup 3/HC-induced chromatid aberrations, respectively. Possible reasons underlying these observations are discussed.

Radiation-Induced Epigenetic Alterations after Low and High LET Irradiations

Energy Technology Data Exchange (ETDEWEB)

Aypar, Umut; Morgan, William F.; Baulch, Janet E.

2011-02-01

Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding the delayed, non-targeted effects of radiation including radiationinduced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET x-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappa B (NFκB), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. MiRNA shown to be altered in expression level after x-ray irradiation are involved in chromatin remodeling and DNA methylation. Different and higher incidence of epigenetic changes were observed after exposure to low LET x-rays than high LET Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This study also shows that the irradiated cells acquire epigenetic changes even though they are chromosomally stable suggesting that epigenetic aberrations may arise in the cell without initiating RIGI.

Radiation-induced epigenetic alterations after low and high LET irradiations

International Nuclear Information System (INIS)

Aypar, Umut; Morgan, William F.; Baulch, Janet E.

2011-01-01

Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding radiation-induced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET X-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappa B (NFκB), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. We demonstrate that miRNA expression levels can be altered after X-ray irradiation and that these miRNA are involved in chromatin remodeling and DNA methylation. A higher incidence of epigenetic changes was observed after exposure to X-rays than Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This distinction is apparent at miRNA analyses at which only three miRNA involved in two major pathways were altered after high LET irradiations while six miRNA involved in five major pathways were altered after low LET irradiations. This study also shows that the irradiated cells acquire epigenetic changes suggesting that epigenetic aberrations may arise in the

Radiation-induced epigenetic alterations after low and high LET irradiations

Energy Technology Data Exchange (ETDEWEB)

Aypar, Umut, E-mail: uaypa001@umaryland.edu [Department of Radiation Oncology, Radiation Oncology Research Laboratory, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Morgan, William F. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Baulch, Janet E. [Department of Radiation Oncology, Radiation Oncology Research Laboratory, University of Maryland School of Medicine, Baltimore, MD 21201 (United States)

2011-02-10

Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding radiation-induced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET X-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappa B (NF{kappa}B), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. We demonstrate that miRNA expression levels can be altered after X-ray irradiation and that these miRNA are involved in chromatin remodeling and DNA methylation. A higher incidence of epigenetic changes was observed after exposure to X-rays than Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This distinction is apparent at miRNA analyses at which only three miRNA involved in two major pathways were altered after high LET irradiations while six miRNA involved in five major pathways were altered after low LET irradiations. This study also shows that the irradiated cells acquire epigenetic changes suggesting that epigenetic aberrations may arise

The Induction of Chromosome Aberrations and Micronuclei in Human Peripheral Blood Lymphocytes at Low Doses of Radiation

CERN Document Server

Shmakova, N L; Krasavin, E A; Melnikova, L A; Fadeeva, T A

2003-01-01

The chromosome damage induced by the low doses of gamma-irradiation with ^{60}Co and X-rays in peripheral blood lymphocytes has been studied using different cytogenetic assays. Isolated lymphocytes were exposed to 0.01-1.0 Gy, simulated by PHA, and analysed for chromosome aberrations by the metaphase and the anaphase methods, by the micronucleus assay. Despite the quantitative differences in the amount of chromosome damage revealed by different methods, all of them demonstrated complex nonlinear dose dependence of the frequency of aberrant cells and aberrations. At the dose range of 0.01-0.05 Gy the cells showed the highest radiosensitivity; at 0.05-0.5 Gy the dose-independent induction of chromosome damage was revealed. At the doses of 0.5-1.0 Gy the dose-effect curves became linear with the decreased slope compared with the initial one (by a factor of 5 to 10 for different criteria) reflecting a higher radioresistance of the cells. These data confirm the idea that the direct linear extrapolation of high-dos...

Biological radiation dose estimation by chromosomal aberrations analysis in human peripheral blood (dose- effect curve)

International Nuclear Information System (INIS)

Al Achkar, W.

2002-01-01

In order to draw a dose-effect curve, blood from eight healthy people were studied. Samples were irradiated in tubes with 0.15-2.5 gray of gamma ray.Irradiated and control samples were incubated for cell cultures. Chromosomal aberrations from 67888 metaphases were scored. Curves from the total number of dicentrics, dicentrics+ rings and total numbers of breaks were drawn. The yield of chromosome aberrations is related to the dose used. These curves give a quick useful estimation of the accidentally radiation exposure. (author)

Time course of enhancement of chromosomal aberration production in human lyphocytes by post-treatment with aphidicolin following X-radiation

International Nuclear Information System (INIS)

Bender, M.A.

1989-01-01

The authors have shown earlier that the DNA polymerase inhibitor, aphidicolin, enhances the production of chromosomal aberration by X-rays when administered as a post-treatment. The effect is marked in metaphases collected for the first hour or two following irradiation. Because the yield of X-ray-induced chromosome aberrations falls rapidly with increasing irradiation-fixation interval in G 2 cells it is possible that a difference in yield between cells post-treated with a drug like aphidicolin and those not-treated could arise simply through alteration of the time required for post-treated cells to reach metaphase. The results of the present experiments agree with those of the earlier one in that the X-ray and X-ray plus 1.5 h 5 x 10 -5 M aphidicolin post-treatment-induced chromatid aberration yield fall very rapidly with increasing X-ray-fixation interval, with the marked excess caused by the post-treatment rapidly disappearing and the yield for post-treated samples fixed between 3 and 6 h post-irradiation becoming no greater than those for samples treated with X-rays alone. The answer to the question of whether the yields increase again at later irradiation-fixation intervals, though complicated by the greater delay in aphidicolin post-treated samples and by admixture at later fixation times of metaphases that were in G 1 when irradiated, appears clearly to be yes. (author). 15 refs.; 3 figs.; 3 figs.; 2 tabs

Low level dose induced chromosome aberrations in human blood lymphocytes

International Nuclear Information System (INIS)

Pohl-Rueling, J.

1992-01-01

Unstable structural aberrations in chromosomes of human blood lymphocytes cannot be used as biological dosemeters in the low dose range, when extrapolating from high doses using a linear dose response, as required by the original formula of the dual radiation action theory. A survey is given of experimental dose-response curves of chromosome aberrations, obtained in investigations not only by this institute, in cooperation with many other laboratories, but also by various authors in different areas of the world. The results are not compatible with the predicted linear dose relationships at in vivo dose ranges up to 30 mGy.y -1 . The aberration frequencies rise sharply with dose within the normal environmental exposure up to about twice that level. At higher doses, aberration frequencies increase less rapidly and reach a plateau. Some in vitro experiments of various authors with higher doses of low LET radiations, up to about 400 mGy have found dose responses with steps. (author)

Anti-topoisomerase drugs as potent inducers of chromosomal aberrations

Directory of Open Access Journals (Sweden)

Loredana Bassi

2000-12-01

Full Text Available DNA topoisomerases catalyze topological changes in DNA that are essential for normal cell cycle progression and therefore they are a preferential target for the development of anticancer drugs. Anti-topoisomerase drugs can be divided into two main classes: "cleavable complex" poisons and catalytic inhibitors. The "cleavable complex" poisons are very effective as anticancer drugs but are also potent inducers of chromosome aberrations so they can cause secondary malignancies. Catalytic inhibitors are cytotoxic but they do not induce chromosome aberrations. Knowledge about the mechanism of action of topoisomerase inhibitors is important to determine the best anti-topoisomerase combinations, with a reduced risk of induction of secondary malignancies.As topoisomerases de DNA catalisam alterações topológicas no DNA que são essenciais para a progressão do ciclo celular normal e, portanto, são um alvo preferencial para o desenvolvimento de drogas anticâncer. Drogas anti-topoisomerases podem ser divididas em duas classes principais: drogas anti-"complexos cliváveis" e inibidores catalíticos. As drogas anti-"complexos cliváveis" são muito eficazes como drogas anticancerígenas, mas são também potentes indutores de aberrações cromossômicas, podendo causar neoplasias malignas secundárias. Inibidores catalíticos são citotóxicos mas não induzem aberrações cromossômicas. Conhecimento a respeito do mecanismo de ação de inibidores de topoisomerases é importante para determinar as melhores combinações anti-topoisomerases, com um reduzido risco de indução de neoplasias malignas secundárias.

Fluorescence in situ hybridisation in chromosome aberration detection in subjects occupationally exposed to ionising radiation

International Nuclear Information System (INIS)

Zeljezic, D.; Garaj-Vrhovac, V.

2005-01-01

For more than two decades, chromosomal aberration analysis has been used to detect structural chromosomal aberrations as sensitive biodosimeters of occupational exposure to ionising radiation. Its use is also recommended by the World Health Organisation. Changes in chromosome structure detected by that method are considered to be early biomarkers of a possible malignant disease. Aberrations detected by the method are unstable and can be found in the lymphocytes of irradiated personnel only within a limited time after exposure. To detect stable chromosomal aberrations, which persist after exposure, multicolour fluorescent in situ hybridisation has to be used. Using DNA probes labelled with different fluorochromes, it dyes each pair of chromosomes with different colour. Due to the dynamic of unstable aberration formation, chromosomal aberration analysis is more suitable in genome damage assessment of recent exposures. On the other hand, fluorescence in situ hybridisation gives the information on chromosome instability caused by long-term occupational exposure to ionising radiation. Considering the high costs of fluorescence in situ hybridisation and the uncertainty of the result, it should be used in biodosimetry only when it is absolutely necessary.(author)

Lack of specificity of chromosome breaks resulting from radiation-induced genomic instability in Chinese hamster cells

International Nuclear Information System (INIS)

Trott, K.-R.; Teibe, A.

1998-01-01

In V79 Chinese hamster cells, radiation-induced genomic instability results in a persistently increased frequency of micronuclei, dicentric chromosomes and apoptosis and in decreased colony-forming ability. These manifestations of radiation-induced genomic instability may be attributed to an increased rate of chromosome breakage events many generations after irradiation. This chromosomal instability does not seem to be a property which has been inflicted on individual chromosomes at the time of irradiation. Rather, it appears to be secondary to an increased level of non-specific clastogenic factors in the progeny of most if not all irradiated cells. This conclusion is drawn from the observations presented here, that all the chromosomes in surviving V79 cells are involved in the formation of dicentric chromosome aberrations 1 or 2 weeks after irradiation with about equal probability if corrections are made for chromosome length. (orig.)

Establishing working standards of chromosome aberrations analysis for biological dosimetry

International Nuclear Information System (INIS)

Bui Thi Kim Luyen; Tran Que; Pham Ngoc Duy; Nguyen Thi Kim Anh; Ha Thi Ngoc Lien

2015-01-01

Biological dosimetry is an dose assessment method using specify bio markers of radiation. IAEA (International Atomic Energy Agency) and ISO (International Organization for Standardization) defined that dicentric chromosome is specify for radiation, it is a gold standard for biodosimetry. Along with the documents published by IAEA, WHO, ISO and OECD, our results of study on the chromosome aberrations induced by radiation were organized systematically in nine standards that dealing with chromosome aberration test and micronucleus test in human peripheral blood lymphocytes in vitro. This standard addresses: the reference dose-effect for dose estimation, the minimum detection levels, cell culture, slide preparation, scoring procedure for chromosome aberrations use for biodosimetry, the criteria for converting aberration frequency into absorbed dose, reporting of results. Following these standards, the automatic analysis devices were calibrated for improving biological dosimetry method. This standard will be used to acquire and maintain accreditation of the Biological Dosimetry laboratory in Nuclear Research Institute. (author)

Comparative analysis of chromosome aberrations in human lymphocytes induced 'in vitro' by various types of ionizing radiation

International Nuclear Information System (INIS)

Todorov, S.

1975-01-01

A quantitative analysis on various types of chromosome aberrations in human peripheral blood lymphocytes after in vitro whole blood irradiation with 180 kV X-rays, gamma rays from cobalt 60, 50 MeV protons and scission neutrons is carried out. The following aberrations are scored: breaks, total number of aberrations, aberrant cells, chromosome fragments, dicentrics and interstitial deletions. The experimental data obtained are statistically processed applying the method of the least squares and employing four mathematical models: Y = cD 2 , Y = cD, Y = a + bD and Y = a + bD + cD 2 . Statistical analysis showed that after treatment with low LET (linear energy transfer) radiations the most suitable for the description of the kinetic of the two break aberrations, total number of aberrations and breaks in relation to dose is the polynomial second degree model, whereas for one break aberrations and aberrant cells - the linear model. The linear model is equally appropriate for one or two breaks aberrations when it is a matter of high LET radiations. Using the linear component of the polynominal second degree equation a comparative characteristic of the RBE (relative biological effectiveness) for the various radiations types is made. The following mean values for RBE are obtained: 0,86 +- 0,44 for gamma radiation from cobalt 60, 0,98 +- 0,06 for 50 MeV protons and 2,38 +- 0,11 for scission neutrons. (A.B.)

Frequencies of chromosome aberration on radiation workers

International Nuclear Information System (INIS)

Yanti Lusiyanti; Zubaidah Alatas

2016-01-01

Radiation exposure of the body can cause damage to the genetic material in cells (cytogenetic) in the form of changes in the structure or chromosomal aberrations in peripheral blood lymphocytes. Chromosomal aberrations can be unstable as dicentric and ring chromosomes, and is stable as translocation. Dicentric chromosome is the gold standard biomarker due to radiation exposure, and chromosome translocation is a biomarker for retrospective biodosimetry. The aim of this studi is to conduct examination of chromosomal aberrations in the radiation worker to determine the potential damage of cell that may arise due to occupational radiation exposure. The examination have been carried out on blood samples from 55 radiation workers in the range of 5-30 year of service. Chromosome aberration frequency measurement starts with blood sampling, culturing, harvesting, slide preparations, and lymphocyte chromosome staining with Giemsa and painting with Fluorescence In Situ Hybridization (FISH) technique. The results showed that chromosomal translocations are not found in blood samples radiation workers and dicentric chromosomes found only on 2 blood samples of radiation workers with a frequency of 0.001/cell. The frequency of chromosomal aberrations in the blood cells such workers within normal limits and this means that the workers have been implemented a radiation safety aspects very well. (author)

Analysis of the dose-response relationships of chromosomal aberrations after irradiation and bleomycin exposure of different human lymphocyte fractions in vitro

International Nuclear Information System (INIS)

Dresp, J.

1979-01-01

Cytogenetic analyses could be carried out on whole blood and pure T-cell cultures and also on cells of the 'buffy-coat'. In pure B-cell cultures even after 96 hours no mitogenic stimulation could be achieved. Parameters of radiosensitivity and bleomycin sensitivity were dicentric chromosomes, for which the dose-response relationships were calculated. Chromosomal investigations on the 'buffy-coat' cells did not provide indications referring to a varying radiosensitivity compared to whole blood cultures. In pure T-cell cultures T-lymphocytes, which had been separated after whole blood irradiation exposure, showed lower aberration rates than lymphocytes, which had been cultured after whole blood irradiation without previous separation. In the case of bleomycin exposure the treatment of previously separated leucocytes and T-lymphocytes respectively, led to lower aberration rates than the treatment before separation. Therefore it is apparently not necessary for a cytogenetic dosimetry or mutagenicity to depart from the whole blood culture method. (orig./MG) [de

Chromosome Aberration on High Level Background Natural Radiation Areas

International Nuclear Information System (INIS)

Yanti-Lusiyanti; Zubaidah-Alatas

2001-01-01

When the body is irradiated, all cells can suffer cytogenetic damage that can be seen as structural damage of chromosome in the lymphocytes. People no matter where they live in world are exposed to background radiation from natural sources both internal and external such as cosmic radiation, terrestrial radiation, cosmogenic radiation radon and thoron. Level of area natural ionizing radiation is varies depending on the altitude, the soil or rock conditions, particular food chains and the building materials and construction features. Level of normal areas of background exposure is annual effective dose 2.4 mSv and the high level areas of background exposure 20 mSv. This paper discuses the frequency of aberration chromosome especially dysenteries in several countries having high level radiation background. It seems that frequency of chromosome aberrations increase, generally with the increase of age of the people and the accumulated dose received. (author)

Time dependence of the yield of chromosome mutations and free radicals in. gamma. -irradiated dry seeds

Energy Technology Data Exchange (ETDEWEB)

Nuzhdin, N I; Samokhvalova, N S; Dozortseva, R L; Petrova, L E; Sheksheev, E M [AN SSSR, Moscow. Inst. Ehvolyutsionnoj Morfologii i Ehkologii Zhivotnykh

1976-07-01

It has been revealed in dry barley seeds that the yield of induced ESR signals and the number of cells having chromosome aberrations depend on the irradiation conditions (single or fractionated exposures, and varying dose rates) and the duration of the post-irradiation storage. Radiobiological effects caused in dry seeds by fractionated irradiation and varying dose rates are of different nature.

Using 3-color chromosome painting to decide between chromosome aberration models

International Nuclear Information System (INIS)

Lucas, J.N.; Sachs, R.K.

1993-01-01

Ionizing radiation produces chromosome aberrations when DNA double strand breaks (DSB) interact pairwise. For more than 30 years there have been two main, competing theories of such binary DSB interactions. The classical theory asserts that an unrepaired DSB makes two ends which separate, with each end subsequently able to join any similar (non-telomeric) end. The exchange theory asserts that the two DSB ends remain associated until repair or a reciprocal chromosome exchange involving a second DSB occurs. The authors conducted an experiment to test these models, using 3-color chromosome painting. After in vitro irradiation of resting human lymphocytes, they observed cells with three-color triplets at first metaphase: three derivative chromosomes having permuted colors, as if three broken chromosomes had played musical chairs. On the exchange model in its standard form such 3-color triplets cannot occur. On the classical model the expected frequency can be calculated. They report data and computer calculations which exclude the exchange model and favor the classical model

Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

Science.gov (United States)

George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

2009-01-01

Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase, DNA-PK activity. Chromosomes were analyzed using the fluorescence in-situ hybridization (FISH) chromosome painting method in cells at the first division post-irradiation and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma radiation induced higher yields of both simple and complex exchanges in the DSB repair defective cells than in the normal cells. The quadratic dose-response terms for both chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further

Elimination of radiation-induced chromosomal damages in numan peripheral blood lymphocyte cultures. 1. The frequency of aberrations in the first and second mitosis

International Nuclear Information System (INIS)

Pyatkin, E.K.; Nugis, V.Yu.

1981-01-01

A comparative analysis of chromosomal aberrations in the first and second mitosis of cultivated human peripheral blood lymphocytes after gamma irradiation in vitro at 1-5 Gy doses has been made. Irradiated blood lymphocytes were incubated for 58 to 66 h at 37 deg with PGA and BDU (20 μg /ml). The first, second and third postradiation mitosises were identified using the distinguishing staining of sister chromatids. The share of the cells in the first mitosis fluctuated from 32 to 77 %, in the second - from 23 to 68 %, and the third - from 0 to 9 %. At all radiation doses significant differences in the frequency of the aberration cells passing the first and second mitosises were revealed as well as in the total number of chromosomal aberrations in all the cells. The frequency of pair fragments and dicentrics chromosomes in the first mitosis was on the average 1.6 and 2 times as high as in the second one, respectively. In the first mitosis almost all dicentric chromosomes occurred with accompanying pair fragments, and in the second mitosis the share of dicentric chromosomes without accompanying fragments was 25 to 50 %. The distribution of the dicentric chromosomes in the cells in the first and second mitosis did not differ from Poison distribution for the 2 to 5 Gy dose range

Effect of gamma irradiation on sex chromatin body appearance and the sex chromosome aberrations in the potato tuber moth, phthorimaea operculella (Lepidoptera: Gelechiidae)

International Nuclear Information System (INIS)

Makee, H.

2007-01-01

Genetic sexing technique based on the construction of a Balanced Lethal Strain (BLS) has been proposed for Phthorimaea operculella (Zeller). The isolation of female with T(W. Z) translocation is a fundamental step to develop such strain. Gamma irradiation was used to induce the requested translocations. The availability of sex-linked morphological marker is required to facilitate the detection of such mutations. Since a visible sex-linked marker has not been found in P. operculella, therefore main aim of our study was to determine the possibility of using sex heterochromatin body as a marker to identify the required translocated females. The appearance of sex heterochromatin body and the analysis of sex chromosomes in F1 females of irradiated P. operculella females were investigated. The percentage of abnormality in sex heterochromatin body in highly polyploid Malpighian tubule nuclei was increased by increasing the applied dose. Based on the appearance of this body, 3 mutant lines were isolated: elongated, small, fragmented lines. W chromosome was easily distinguished from Z chromosome when the analysis of pachytene sex chromosome bivalents of P. operculella females was carried out. The aberrations involved W chromosome directly influenced the appearance of sex heterochromatin body in highly polyploid somatic cells of the isolated mutant lines. The results showed that sex heterochromatin could be used as sex determination and cytogenetic marker in P. operculella. (Author)

Effect of gamma irradiation on sex chromatin body appearance and the sex chromosome aberrations in the potato tuber moth, phthorimaea operculella (Lepidoptera: Gelechiidae)

International Nuclear Information System (INIS)

Makee, H.

2006-05-01

Genetic sexing technique based on the construction of a Balanced Lethal Strain (BLS) has been proposed for Phthorimaea operculella (Zeller). The isolation of female with T(W; Z) translocation is a fundamental step to develop such strain. Gamma irradiation was used to induce the requested translocations. The availability of sex-linked morphological marker is required to facilitate the detection of such mutations. Since a visible sex-linked marker has not been found in P. operculella, therefore main aim of our study was to determine the possibility of using sex heterochromatin body as a marker to identify the required translocated females. The appearance of sex heterochromatin body and the analysis of sex chromosomes in F1 females of irradiated P. operculella females were investigated. The percentage of abnormality in sex heterochromatin body in highly polyploid Malpighian tubule nuclei was increased by increasing the applied dose. Based on the appearance of this body, 3 mutant lines were isolated: elongated, small, fragmented lines. W chromosome was easily distinguished from Z chromosome when the analysis of pachytene sex chromosome bivalents of P. operculella females was carried out. The aberrations involved W chromosome directly influenced the appearance of sex heterochromatin body in highly polyploid somatic cells of the isolated mutant lines. The results showed that sex heterochromatin could be used as sex determination and cytogenetic marker in P. operculella. (Author)

Radioprotective effects of histamine H2 receptor antagonists famotidine and ranitidine on gamma ray induced chromosome damage

International Nuclear Information System (INIS)

Sharma, N.K.

2013-01-01

Histamine H2 receptor antagonist such as Cimetidine, Famotidine and Ranitidine are used in the clinical treatment of peptic ulcer. In vitro metaphase analysis and micronucleus assay were used to test the effects of famotidine and ranitidine on Cobalt 60 γ-ray induced clastogenic effects. Heparinised whole blood was obtained from healthy non-smoker volunteers. Blood samples were irradiated at a dose of 3Gy and incubated at 37 deg C for 1h. Lymphocyte cultures were initiated for metaphase chromosomes and cytochalasin B blocked micronucleus analysis. Aqueous solution of Famotidine (150 g/ml) and Ranitidine (500 g/ml) was added to the whole blood cultures at 0h and 24h. Cultures were harvested and processed at 48h and 72h for chromosome aberrations and micronucleus analysis respectively. Cultures treated with Famotidine at 0h and 24h after 3Gy γ-ray irradiation induce 60.90% and 56.52% inhibition in dicentrics, 48.70% and 43.61% inhibition in total aberrations. Ranitidine at 0h and 24h after 3Gy γ-ray irradiation induce 52.17% and 43.47% inhibition in dicentrics, 33.60% and 46.15% inhibition in total aberrations, when compared with 3Gy γ-ray irradiation alone. 43-54% inhibition in Binucleated cells with micronuclei and 47.72% inhibition in micronuclei at 0h treatment respectively. In conclusion radioprotective effects of Histamine H2 receptor antagonists famotidine and ranitidine on γ-ray induced chromosome damage is observed and the drugs effectively reduced the frequency of radiation induced chromosome aberrations and micronucleus. Famotidine was found to be more effective. The mechanism in which these drugs reduce clastogenic effect of γ-radiation is not fully understood. It might be due to their antioxidant and free radical-scavenging properties. (author)

Radiation-induced chromosome breakages in bread wheat (Triticum aestivum L.)

International Nuclear Information System (INIS)

Larik, A.S.

1975-01-01

Meiosis and pollen fertility were studied in the M 2 generation in four varieties of hexaploid wheat. Meiosis was characterized by the formation of interchange configurations, such as rings and chains of four chromosomes in several cells. Chromosomal aberrations showed linear relationship with gamma irradiation; 45 kR dose induced the highest chromosomal abnormalities. Most multivalents were interchange rings of four chromosomes. Translocations involving two pairs of homologous or nonhomologous chromosomes seemed to be higher in frequency than those involving more than two pairs of chromosomes. Anaphase abnormalities, such as laggards, bridges and fragments and unequal segregation of chromosomes, were frequently observed. Pollen fertility was considerably reduced in the M 2 plants arising form the treatments of higher doses of gamma rays because of the induced chromosome interchanges. (author)

Transmission of chromosomal and instability via a chromosome irradiated with ionizing radiation

International Nuclear Information System (INIS)

Kodama, Seiji; Tanabe, Masateru; Shiraishi, Kazunori; Oshimura, Mitsuo

2010-01-01

We examined the stability of the transferred chromosome in 5 and 12 microcell hybrids including unirradiated human chromosomes 6 and 8, respectively, and 6 and 19 microcell hybrids including 4 Gy-irradiated human chromosomes 6 and 8, respectively. The transferred chromosome was structurally stable in most microcell hybrids transferred with the unirradiated chromosomes 6 and 8. In contrast, the 4 Gy-irradiated human chromosomes were unstable in 3 out of 6 hybrids (50%) with chromosome 6 and 3 out of 19 hybrids (16%) with chromosome 8, showing multiple aberrations in high frequencies (35∼98%). To know the cause of delayed chromosomal instability, intrachromosomal rearrangements of the human chromosome is investigated by subtelomere FISH in 17 microcell hybrids transferred with chromosomes 6 and 8. We found frequent intrachromosomal in 7 microcell hybrids (41%). However, no clear correlation was observed between the intrachromosomal rearrangements and the induction of delayed chromosomal instability by ionizing radiation

Effect of vitamin E on preovulatory stage irradiated female mouse expressed as chromosomal abnormalities in generated embryos

International Nuclear Information System (INIS)

Salimi, M.; Mozdarani, H.

2006-01-01

The present study has been carried out to investigate the effects of preovulatory stage gamma-irradiation of female mice in the absence or presence of vitamin E on numerical chromosome abnormalities in 8-cell embryos after mating with non- irradiated males. Materials and Methods: The 8-11 weeks adult female NMRl mice were whole body irradiated at preovulatory stage (post PMSG injection and about 12-18 hours before Injecting HCG) with 4 Gy gamma-rays generated from a cobalt-60 source alone or in combination with 200 IU/kg vitamin E, intraperitoneally administered one hour prior to irradiation. Soon after HCG injection super ovulated irradiated females were mated with non-irradiated males. About 68-h post coitus (p.c), 8-cell embryos were flushed from the oviducts of pregnant mice and were fixed on slides using standard methods in order to screen for metaphase spreads and numerical chromosome abnormalities. Results: In control embryos, 8% of metaphase plates were aneuploidy whereas in preovulatory stage irradiated female mice, about 50% of metaphase plates of embryos showed numerical chromosome aberrations (P nd meiotic division. Reduction of the frequency of chromosome aberrations in the presence of vitamin E is probably due to antioxidant effects of this vitamin, and scavenging free radicals induced by gamma-rays in mice oocytes' environment

Chromosomal aberrations induced by alpha particles; Aberraciones cromosomicas inducidas por particulas {alpha}

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Guerrero C, C.; Brena V, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: cgc@nuclear.inin.mx

2005-07-01

The chromosomal aberrations produced by the ionizing radiation are commonly used when it is necessary to establish the exposure dose of an individual, it is a study that is used like complement of the traditional physical systems and its application is only in cases in that there is doubt about what indicates the conventional dosimetry. The biological dosimetry is based on the frequency of aberrations in the chromosomes of the lymphocytes of the individual in study and the dose is calculated taking like reference to the dose-response curves previously generated In vitro. A case of apparent over-exposure to alpha particles to which is practiced analysis of chromosomal aberrations to settle down if in fact there was exposure and as much as possible, to determine the presumed dose is presented. (Author)

Chromosomal aberrations in ore miners of Slovakia

International Nuclear Information System (INIS)

Beno, M.; Vladar, M.; Nikodemova, D.; Vicanova, M.; Durcik, M.

1998-01-01

A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

Chromosomal rearrangements caused by gamma-irradiation in winter wheat cells

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M. M. Nazarenko

2017-02-01

Full Text Available In this article we report the results of our investigation into several cytogenetic parameters of variability in mutation induction of modern winter wheat varieties and some connections between the means of cytogenetic indices and different doses of gamma-rays. Analysis of chromosomal aberrations following the action of any kind of mutagen by the anaphases method is one of the most widely investigated and most precise methods which can be used to determine the fact of mutagenic action on plants and identify the nature of the mutagen. We combined in our investigation the sensitivity of genotype to mutagen using cytological analysis of mutagen treated wheat populations with the corresponding different varieties by breeding methods to reveal its connections and differences, specific sensitivity to mutagens action on the cell level. Dry seeds of 8 varieties of winter wheat were subjected to 100, 150, 200, 250 Gy gamma irradiation, which are trivial for winter wheat mutation breeding. We investigated rates and spectra of chromosomal aberrations in the cells of winter wheat primary roots tips. The coefficients of correlations amid the rate of chromosomal aberrations and the dose of gamma-rays were on the level 0.8–0.9. The fragments/bridges ratio is a clear and sufficient index for determining the nature of the mutagen agent. We distinguished the following types of chromosomal rearrangements: chromatid and chromosome bridges, single and double fragments, micronuclei, and delayed chromosomes. The ratio of chromosomal aberrations changes with the change in mutagen; note that bridge-types are characteristic of irradiation. Radiomutants are more resistant to gamma rays. This is apparent in the lower rate of chromosomal aberrations. Varieties obtained by chemical mutagenesis (varieties Sonechko, Kalinova are more sensitive to gamma-irradiation than others. We propose these varieties as objects for a mutation breeding programme and radiation of mutants

High resistance of fibroblasts from Mongolian gerbil embryos to cell killing and chromosome aberrations by X-irradiation

International Nuclear Information System (INIS)

Suzuki, F.; Nakao, N.; Nikaido, O.; Kondo, S.

1992-01-01

Mongolian gerbil (Meriones unguiculatus) is known to be one of the most radioresistant animal species. In order to determine whether there is any correlation between mortality of mammals exposed to γ- or X-rays and radiation sensitivity of culture cells derived from different mammalian species, we have examined the X-ray survival curves of normal diploid fibroblasts from Mongolian gerbil embryos and compared with those of other cultured embryo cells from various laboratory animals and normal human. There was a big difference in cell survival to X-rays among different mammalian species. The D 0 values of Mongolian gerbil cells ranged from 2.3 to 2.6 Gy which are twice as high as those of human cells. The mean D 0 value of human cells was 1.1 Gy. Mouse, rat, Chinese hamster and Syrian/golden hamster cells showed similar D 0 values ranging from 1.7 to 2.0 Gy. When cells were irradiated with 2 Gy of X-rays, three times longer mitotic delay was observed in human cells than in Mongolian gerbil cells. At this X-ray dose, furthermore, ten times more chromosome aberrations were detected in human cells than in Mongolian gerbil cells, and the frequencies of other rodent cells lay between the values for the two cell strains. These data indicate that the Mongolian gerbil cells are resistant to X-ray-induced cell killing and chromosome aberrations, and that radiation sensitivity of primarily cultured mammalian cells may be reflected by their radioresistance in vivo. (author)

Transfer of unstable chromosomal aberrations in human peripheral lymphocytes at cell division and their significance for the aberration frequency

International Nuclear Information System (INIS)

Stephan, G.; Chang Tsangpi.

1986-04-01

In 48 h cultures, the fraction of human lymphocytes in 2nd mitosis was found to be between 0 and 42.5% (mean value 8.7%). The X-ray exposure from irradiating with 2 Gy resulted in a cell cycle delay which varied from donor to donor. A loss of nearly 50% of dicentric chromosomes and acentric fragments from unstable chromosomes occurred at cell division, while centric rings were not impeded. When dicentric chromosomes, or acentric fragments are found in 2nd mitosis, they show a characteristic differential staining, which means that chromatides at cell division fall free and are replicated in daughter cells. When plotting dose effect curves of dicentric chromosomes, up to 20% of 2nd mitosis fractions have little influence on the aberration rate. This may be additionally verified as part of the 'biological dosimetry' in a person with 24% of 2nd mitosis. When the rates of dicentric chromosomes exclusively evaluated from 1st mitosis after irradiation with 2.0 Gy were related to the donors age, no age-dependent sensitivity to radiation could be observed. Aberration rates which deviate from person to person are comparable to the results achieved by conventional staining methods. (orig./MG) [de

Dependence of Early and Late Chromosomal Aberrations on Radiation Quality and Cell Types

Science.gov (United States)

Lu, Tao; Zhang, Ye; Krieger, Stephanie; Yeshitla, Samrawit; Goss, Rosalin; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Rohde, Larry; Wu, Honglu

2017-01-01

Exposure to radiation induces different types of DNA damage, increases mutation and chromosome aberration rates, and increases cellular transformation in vitro and in vivo. The susceptibility of cells to radiation depends on genetic background and growth condition of cells, as well as types of radiation. Mammalian cells of different tissue types and with different genetic background are known to have different survival rate and different mutation rate after cytogenetic insults. Genomic instability, induced by various genetic, metabolic, and environmental factors including radiation, is the driving force of tumorigenesis. Accurate measurements of the relative biological effectiveness (RBE) is important for estimating radiation-related risks. To further understand genomic instability induced by charged particles and their RBE, we exposed human lymphocytes ex vivo, human fibroblast AG1522, human mammary epithelial cells (CH184B5F5/M10), and bone marrow cells isolated from CBA/CaH(CBA) and C57BL/6 (C57) mice to high energy protons and Fe ions. Normal human fibroblasts AG1522 have apparently normal DNA damage response and repair mechanisms, while mammary epithelial cells (M10) are deficient in the repair of DNA DSBs. Mouse strain CBA is radio-sensitive while C57 is radio-resistant. Metaphase chromosomes at different cell divisions after radiation exposure were collected and chromosome aberrations were analyzed as RBE for different cell lines exposed to different radiations at various time points up to one month post irradiation.

Radiation induced wheat-rye chromosomal translocations in triticale. Optimizing the dose using fluorescence in situ hybridization

International Nuclear Information System (INIS)

Ahmad, F.; Comeau, A.; Chen, Q.; Collin, J.; St-Pierre, C.A.

2000-01-01

Fluorescent in situ hybridization (FISH) was utilized to monitor the level of ionizing radiation ( 60 Co source) in their ability to cause intra- and intergeneric chromosomal aberrations in triticale seeds. Seeds were irradiated with 0, 20, 50, 100, 200, 300, 400, 500 and 1000 Gy doses. The root growth of irradiated seeds was greatly inhibited at 200 Gy and above. Various types of aberrations including wheat-rye, wheat-wheat, rye-rye, wheat-rye-wheat, rye-wheat-rye translocations and acentric fragments with or without translocations were observed. There was a consistent increase in proportion of aberrations per cell with an increase in radiation dose. It was concluded that for an optimal level of chromosomal translocation and least number of acentric fragments, a 20 Gy dose was quite sufficient for inducing a desirable level of wheat-rye chromosomal translocations. The excellent efficiency and importance of utilizing FISH in such studies of alien-introgression via chromosomal translocations are discussed. (author)

Radiation induced wheat-rye chromosomal translocations in triticale. Optimizing the dose using fluorescence in situ hybridization

Energy Technology Data Exchange (ETDEWEB)

Ahmad, F. [Brandon Univ., Manitoba (Canada); Comeau, A.; Chen, Q.; Collin, J.; St-Pierre, C.A.

2000-03-01

Fluorescent in situ hybridization (FISH) was utilized to monitor the level of ionizing radiation ({sup 60}Co source) in their ability to cause intra- and intergeneric chromosomal aberrations in triticale seeds. Seeds were irradiated with 0, 20, 50, 100, 200, 300, 400, 500 and 1000 Gy doses. The root growth of irradiated seeds was greatly inhibited at 200 Gy and above. Various types of aberrations including wheat-rye, wheat-wheat, rye-rye, wheat-rye-wheat, rye-wheat-rye translocations and acentric fragments with or without translocations were observed. There was a consistent increase in proportion of aberrations per cell with an increase in radiation dose. It was concluded that for an optimal level of chromosomal translocation and least number of acentric fragments, a 20 Gy dose was quite sufficient for inducing a desirable level of wheat-rye chromosomal translocations. The excellent efficiency and importance of utilizing FISH in such studies of alien-introgression via chromosomal translocations are discussed. (author)

Chromosome painting analysis of X-ray-induced aberrations in human lymphocytes in vitro

International Nuclear Information System (INIS)

Matsuoka, A.; Hayashi, M.; Yamazaki, N.; Sofuni, T.

1994-01-01

Chromosomal rearrangements in human lymphocytes induced by X-rays (0, 0.5, 1.0 and 2.0 Gray) were analyzed using chromosome painting. DNA probes for human chromosomes 1, 3 or 4 alone, and a combination of 1 and 4, were used for analysis. The frequency of cells with rearrangements, i.e. reciprocal translocations, dicentrics, insertions, tricentrics and fragments, involving chromosome 4 increased with dose in both 48 and 72 h cultures. The number of translocations per cell also increased with dose at 48 and 72 h. Dicentrics increased with dose in 48 h but not in 72 h cultures. The estimated genomic frequency of aberrations per cell was comparable with results in banded cells. No difference was shown on the detection efficiency of chromosome rearrangements among the various DNA probes used. Since this technique does not necessarily require well-spread metaphases for analysis, it is possible to increase the number of analyzable metaphases compared with the banding technique. Chromosome painting is a simpler, more objective and practical method for detecting chromosome rearrangements than conventional banding analyses. (Author)

Formation of radiation induced chromosome aberrations: involvement of telomeric sequences and telomerase

International Nuclear Information System (INIS)

Pirzio, L.

2004-07-01

As telomeres are crucial for chromosome integrity; we investigated the role played by telomeric sequences in the formation and in the transmission of radio-induced chromosome rearrangements in human cells. Starting from interstitial telomeric sequences (ITS) as putative region of breakage, we showed that the radiation sensitivity is not equally distributed along chromosomes and. is not affected by ITS. On the contrary, plasmid integration sites are prone to radio-induced breaks, suggesting a possible integration at sites already characterized by fragility. However plasmids do not preferentially insert at radio-induced breaks in human cells immortalized by telomerase. These cells showed remarkable karyotype stability even after irradiation, suggesting a role of telomerase in the genome maintenance despite functional telomeres. Finally, we showed that the presence of more breaks in a cell favors the repair, leading to an increase of transmissible rearrangements. (author)

Factors that determine the in vivo dose-response relationship for stable chromosome aberrations in A-bomb survivors

International Nuclear Information System (INIS)

Awa, A.A.; Nakano, Mimako; Ohtaki, Kazuo; Kodama, Yoshiaki; Lucas, J.; Gray, J.

1992-01-01

An overview is given of the dose-response relationship for stable chromosome aberrations (i.e., translocations and inversions) in the peripheral blood lymphocytes of A-bomb survivors in Hiroshima. Special emphasis is placed on (i) the overdispersion of survivor cases with either unexpectedly high or low aberration frequencies relative to the estimated DS86 kerma values assigned to individual survivors, termed 'cytogenetic outliers', and (ii) the correlation of chromosome aberration frequencies with other biological endpoints, such as acute radiation symptoms (severe epilation). A new molecular biological technique, known as fluorescence in situ hybridization (FISH) with composite, whole-chromosome probes to paint differentially the target chromosomes, has facilitated rapid, efficient, and extensive scoring of translocation-type chromosome aberrations in which the target chromosomes are involved. Using this methodology, the observed findings on translocation frequencies in A-bomb survivors have shown that the frequency of stable chromosome aberrations, which have persisted for years without change in frequency in irradiated persons, is indeed useful as an indicator for biological dosimetry. (author)

Comparative studies of radiation-induced chromosome aberrations in several mammalian species

International Nuclear Information System (INIS)

Muramatsu, S.; Matsuoka, O.

1976-01-01

The dose-response relationship for inducing chromosome aberrations in peripheral lymphocytes of five mammalian species - man, cynomolgus monkey, rabbit, domestic cat and beagle dog - were studied comparatively by whole-blood microculture technique following in-vitro exposures at various doses with 200-kVp X rays. The yields of induced chromosome aberrations were dependent on exposure doses between 48 and 480 rads in all the species examined. The relationship between exposure dose (D in rads) and frequency of induced dicentrics per cell (Y) was expressed by: Ysub((man)) = 14.38x10 -6 Dsup(1.94); Ysub((monkey)) = 18.12x10 -6 Dsup(1.86); Ysub((rabbit)) = 1.88x10 -6 Dsup(2.06); Ysub((cat)) = 78.66x10 -6 Dsup(1.35); Ysub((dog)) = 46.13x10 -6 Dsup(1.37). Taking the frequency of dicentrics in man as 1.00, the relative frequency in each species was estimated as 0.79, 0.24, 0.22 and 0.16 in monkey, rabbit, cat and dog, respectively. From these results the consistent relationship could not be discovered between X-ray doses and the dicentric yield based on the arm number effect proposed by Brewen et al., whereas the nuclear DNA contents and the arm number in all the species used are roughly similar to those in man. The authors considered that such interspecies differences may be derived from the cellular and/or physiological features of PHA-responsible lymphocytes (T-cells) in each species, and that may be due to the level of development of each species on the phylogenetic or evolutionary scale. (author)

Studies on chromosome aberrations in workers occupationally exposed to radiation

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hyung; Oh, Hyeon Joo; Shim, Sun Bo; Roh, Hye Won; Lee, Hai Yong [Korea Food and Drug Administration, Seoul (Korea, Republic of); Kang, Soon Ja [Ewha Womens Univ., Seoul (Korea, Republic of)

1998-06-01

Cytogenetic assays for unstable chromosomes were performed on 54 medical radiation workers who are occupationally exposed to radiation and 42 controls. A total of 15,577 metaphase cells were scored. The frequencies of dicentrics and acentric chromosomes on controls were 0.52*10{sup -3} and 0.82*10{sup -2}, respectively. On radiation workers those were 2.28*10{sup -3} and 1.34*10{sup -2}, respectively. Though the frequencies of all types of chromosome aberrations in the workers were higher than those in the controls, the only significant difference was found in the case of dicentrics (P < 0.01). When we considered exposure dose of recent one year, duration of employment and smoking habit in radiation worker, a slight increase was shown in frequency of unstable chromosome aberrations on these workers, but no statistical differences were observed (P > 0.05) except exposure dose of recent one year (P < 0.05). These results could indicate that low level exposure to ionizing radiation can induce unstable chromosome aberrations in blood lymphocytes.

Impact of various parameters in detecting chromosomal aberrations by FISH to describe radiosensitivity

International Nuclear Information System (INIS)

Keller, U.; Mueller, E.; Grabenbauer, G.; Sauer, R.; Distel, L.; Kuechler, A.; Liehr, T.

2004-01-01

Background and purpose: analysis of radiation-induced chromosomal aberrations is regarded as the ''gold standard'' for classifying individual radiosensitivity. A variety of different parameters can be used. The crucial question, however, is to explore which parameter is suited best to describe the differences between patients with increased radiosensitivity and healthy individuals. Patients and methods: in this study, five patients with severe radiation-induced late effects of at least grade 3, classified according to the Radiation Therapy Oncology Group (RTOG), and eleven healthy individuals were examined retrospectively. Peripheral blood lymphocytes were irradiated in vitro with 0.7 Gy and 2.0 Gy prior to cultivation and stained by means of three-color fluorescence in situ hybridization (FISH). The detailed analysis was focused on the number of breaks per metaphase, on breaks from complex chromosomal rearrangements per metaphase, as well as on the percentage of translocations, dicentric chromosomes, breaks, and excess acentric fragments - each in comparison with the total number of mitoses analyzed. Results: using the number of breaks from complex chromosomal rearrangements after 2.0 Gy, radiosensitive patients as endpoint were clearly to be distinguished (p = 0.001) from healthy individuals. Translocations (p = 0.001) as well as breaks per metaphase (p = 0.002) were also suitable indicators for detecting differences between patients and healthy individuals. The parameters ''percentage of dicentric chromosomes'', ''breaks'', and ''excess acentric fragments'' in comparison to the total number of mitoses analyzed could neither serve as meaningful nor as significant criteria, since they showed a strong interindividual variability. Conclusion: to detect a difference in chromosomal aberrations between healthy and radiosensitive individuals, the parameters ''frequency of breaks per metaphase'', ''complex chromosomal rearrangements'', and ''translocations'' are most

Lethality of radiation-induced chromosome aberrations in human tumour cell lines with different radiosensitivities.

Science.gov (United States)

Coco-Martin, J M; Ottenheim, C P; Bartelink, H; Begg, A C

1996-03-01

In order to find an explanation for the eventual disappearance of all chromosome aberrations in two radiosensitive human tumour cell lines, the type and stability of different aberration types was investigated in more detail. To classify the aberrations into unstable and stable types, three-colour fluorescence in situ hybridization was performed, including a whole-chromosome probe, a pancentromere probe, and a stain for total DNA. This technique enables the appropriate classification of the aberrations principally by the presence (stable) or not (unstable) of a single centromere per chromosome. Unstable-type aberrations were found to disappear within 7 days (several divisions) in the two radiosensitive and the two radioresistant tumour lines investigated. Stable-type aberrations were found to remain at an approximately constant level over the duration of the experiment (14 days; 8-10 divisions) in the two radioresistant lines. In contrast, the majority of these stable-type aberrations had disappeared by 14 days in the two radiosensitive lines. The previous findings of disappearance of total aberrations in radiosensitive cells was therefore not due to a reduced induction of stable-type aberrations, but the complete disappearance of cells with this aberration type. These results could not be explained by differences in apoptosis or G1 blocks. Two possible explanations for these unexpected findings involve non-random induction of unstable-type aberrations, or lethality of stable-type aberrations. The results suggest caution in the use of stable-type aberration numbers as a predictor for radiosensitivity.

An algorithm for automatic detection of chromosome aberrations induced by radiation using features of gray level profile across the main axis of chromosome image

International Nuclear Information System (INIS)

Kawashima, Hironao; Imai, Katsuhiro; Fukuoka, Hideya; Yamamoto, Mikio; Hayata, Isamu.

1990-01-01

A simple algorithm for detecting chromosome aberrations induced by radiation is developed. Microscopic images of conventional Giemsa stained chromosomes of rearranged chromosomes (abnormal chromosomes) including dicentric chromosomes, ordinary acentric fragments, small acentric fragments, and acentric rings are used as samples. Variation of width along the main axis and gray level profile across the main axis of the chromosome image are used as features for classification. In 7 microscopic images which include 257 single chromosomes, 90.0% (231 chromosomes) are correctly classified into 6 categories and 23 of 26 abnormal chromosomes are correctly identified. As a result of discrimination between a normal and an abnormal chromosome, 95.3% of abnormal chromosomes are detected. (author)

The Distribution of Chromosomal Aberrations in Human Cells Predicted by a Generalized Time-Dependent Model of Radiation-Induced Formation of Aberrations

Science.gov (United States)

Ponomarev, Artem L.; George, K.; Cucinotta, F. A.

2011-01-01

New experimental data show how chromosomal aberrations for low- and high-LET radiation are dependent on DSB repair deficiencies in wild-type, AT and NBS cells. We simulated the development of chromosomal aberrations in these cells lines in a stochastic track-structure-dependent model, in which different cells have different kinetics of DSB repair. We updated a previously formulated model of chromosomal aberrations, which was based on a stochastic Monte Carlo approach, to consider the time-dependence of DSB rejoining. The previous version of the model had an assumption that all DSBs would rejoin, and therefore we called it a time-independent model. The chromosomal-aberrations model takes into account the DNA and track structure for low- and high-LET radiations, and provides an explanation and prediction of the statistics of rare and more complex aberrations. We compared the program-simulated kinetics of DSB rejoining to the experimentally-derived bimodal exponential curves of the DSB kinetics. We scored the formation of translocations, dicentrics, acentric and centric rings, deletions, and inversions. The fraction of DSBs participating in aberrations was studied in relation to the rejoining time. Comparisons of simulated dose dependence for simple aberrations to the experimental dose-dependence for HF19, AT and NBS cells will be made.

Brahmarasayana protects against Ethyl methanesulfonate or Methyl methanesulfonate induced chromosomal aberrations in mouse bone marrow cells

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Guruprasad Kanive

2012-08-01

Full Text Available Abstract Background Ayurveda, the traditional Indian system of medicine has given great emphasis to the promotion of health. Rasayana is one of the eight branches of Ayurveda which refers to rejuvenant therapy. It has been reported that rasayanas have immuno-modulatory, antioxidant and antitumor functions, however, the genotoxic potential and modulation of DNA repair of many rasayanas have not been evaluated. Methods The present study assessed the role of Brahmarasayana (BR on Ethyl methanesulfonate (EMS-and Methyl methanesulfonate (MMS-induced genotoxicity and DNA repair in in vivo mouse test system. The mice were orally fed with BR (5 g or 8 mg / day for two months and 24 h later EMS or MMS was given intraperitoneally. The genotoxicity was analyzed by chromosomal aberrations, sperm count, and sperm abnormalities. Results The results have revealed that BR did not induce significant chromosomal aberrations when compared to that of the control animals (p >0.05. On the other hand, the frequencies of chromosomal aberrations induced by EMS (240 mg / kg body weight or MMS (125 mg / kg body weight were significantly higher (p Conclusion The effect of BR, as it relates to antioxidant activity was not evident in liver tissue however rasayana treatment was observed to increase constitutive DNA base excision repair and reduce clastogenicity. Whilst, the molecular mechanisms of such repair need further exploration, this is the first report to demonstrate these effects and provides further evidence for the role of brahmarasayana in the possible improvement of quality of life.

Studies on chromosome aberrations induced in human lymphocytes by very low-dose exposure to tritium

International Nuclear Information System (INIS)

Hori, T.; Moriya, Junko; Nakai, Sayaka

1978-01-01

Assessment of potential hazard from environmental tritium to man becomes very important with increasing the development of nuclear-power industry. However, little data are available as to the determination on the genetic effect of tritium especially at the low levels. The object of the present study is to obtain quantitative data for chromosome aberrations in human lymphocytes, as an indicator for genetic risk estimation, induced by tritium at very low dose levels. Leukocyte cultures of human peripheral blood were chronically exposed for 48h to tritiated water and 3 H-thymidine using a wide range of tritium doses, and aberrations in lymphocyte chromosomes at the first metaphases were examined. In the experimental conditions, the types of aberrations induced by radiation emitted from both tritiated water and 3 H-thymidine were mostly chromatid types, such as chromatid gaps and deletions. The dose-response relations for chromatid breaks per cell exhibited unusual dose-dependency in both cases. It was demonstrated that at higher dose range the yields of chromatid breaks increased linearly with dose, while those at lower dose range were significantly higher than would be expected by a downward extraporation from the linear relation. Partial-hit or partial-target kinetics events appeared at very low dose exposure. (author)

Chromosome aberrations in pesticide-exposed greenhouse workers

DEFF Research Database (Denmark)

Lander, B F; Knudsen, Lisbeth E.; Gamborg, M O

2000-01-01

OBJECTIVES: The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers. METHODS: In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116...... greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents. RESULTS: The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse...... workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding...

Meiotic chromosomal translocations in male mice induced by X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Savkovic, N.; Pecevski; Vuksanovic, L.; Radivojevic, D.; Alavantic, D.

1983-01-01

The dose-response curve for reciprocal translocations induced by acute exposure of spermatogonial stem cells to X-rays in treated mice and their F-1 sons was examined. Male mice were totally irradiated with doses of 1Gy;5x1Gy and 5Gy. The obtained results show that frequency of the chromosomal translocations in directly treated animals is dose dependent. The percentage of animals irradiated with 1Gy which had the chromosomal translocations was 60, while this percentage in animals irradiated with single and fractionated dose of 5Gy was 100. The frequency of chromosomal translocations varies from 1.5% to 8.0%. Multivalent configurations in F-1 males were observed after exposure to 5Gy only. The incidence of F-1 translocated males was 17.5%.

Simulations of DSB Yields and Radiation-induced Chromosomal Aberrations in Human Cells Based on the Stochastic Track Structure iIduced by HZE Particles

Science.gov (United States)

Ponomarev, Artem; Plante, Ianik; George, Kerry; Wu, Honglu

2014-01-01

The formation of double-strand breaks (DSBs) and chromosomal aberrations (CAs) is of great importance in radiation research and, specifically, in space applications. We are presenting a new particle track and DNA damage model, in which the particle stochastic track structure is combined with the random walk (RW) structure of chromosomes in a cell nucleus. The motivation for this effort stems from the fact that the model with the RW chromosomes, NASARTI (NASA radiation track image) previously relied on amorphous track structure, while the stochastic track structure model RITRACKS (Relativistic Ion Tracks) was focused on more microscopic targets than the entire genome. We have combined chromosomes simulated by RWs with stochastic track structure, which uses nanoscopic dose calculations performed with the Monte-Carlo simulation by RITRACKS in a voxelized space. The new simulations produce the number of DSBs as function of dose and particle fluence for high-energy particles, including iron, carbon and protons, using voxels of 20 nm dimension. The combined model also calculates yields of radiation-induced CAs and unrejoined chromosome breaks in normal and repair deficient cells. The joined computational model is calibrated using the relative frequencies and distributions of chromosomal aberrations reported in the literature. The model considers fractionated deposition of energy to approximate dose rates of the space flight environment. The joined model also predicts of the yields and sizes of translocations, dicentrics, rings, and more complex-type aberrations formed in the G0/G1 cell cycle phase during the first cell division after irradiation. We found that the main advantage of the joined model is our ability to simulate small doses: 0.05-0.5 Gy. At such low doses, the stochastic track structure proved to be indispensable, as the action of individual delta-rays becomes more important.

Spontaneous chromosome aberrations in cancer cells. Evidence of existence of hidden genetic lesions in genetic structures

International Nuclear Information System (INIS)

Poryadkova-Luchnik, N.A.; Kuz'mina, E.G.

1996-01-01

Chromosome aberrations spontaneously observed in cancer cells were quantitively studied under the effect of non-mutagenic (suboptimal temperature, low content of propilgallate and caffeine) and mutagenic (ionizing radiation) factors. Human larynx cancer cells during several years or gamma-irradiation were used to carry out experiments. The experiments linked with cloning of the initial population and investigation into chromosome aberrations in 22 clones demonstrated persuasively the occurrence of latent genetic lesions in cancer cells

Induced chromosomal aberrations in somatic cells of Nigella sativa L. by mitomycin C.

Science.gov (United States)

Kumar, P; Nizam, J

1978-01-01

A cytological study was carried out on root tips of Nigella sativa L. by treatment with Mitomycin C at 0.001% for six time intervals (10, 15, 20, 30, 40, and 50 min). The chromosomal abnormalities were increasingly proportionate to the increase in time of treatment. The seedlings treated with a 0.001% concentration of Mitomycin C for 10 min. did not show any significant effect. At other time intervals, the effect was observed to be quite significant. Beyond 40 min. treatment almost all the cells would become sticky. Thirty minutes' treatment showed significant effect, inducing various types of chromosomal aberrations in the anaphase, such as bridges and fragments of 34.13% and 48.07%, respectively.

Experimental investigations of chromosomal aberrations following irradiation with fast electrons at various irradiation depths as influenced by sulfoguanidine

International Nuclear Information System (INIS)

Donnerstag, R.

1975-01-01

Root tips of Vicia faba were irradiated with fast electrons (14.2 MeV, 120 rad) in the phantom at a depth of 100% and 30% relative depth dose in culture medium and sulphoguanidine solution and were fixed after 3, 6, 9, 12 and 24 h. In contrast to the controls, a transitory mitotic depression was observed after irradiation. This effect was more marked for root tips irradiated in culture medium and much less pronounced in root tips irradiated in sulphoguanidine. When quantitatively assessing the anaphasal aberrations, the highest damage rate was found at 3 h p.r. This was attributed to the facts that these cells had been irradiated in the earliest G 2 phase. A second aberration peak was found 9 h after irradiation at 30% relative depth dose. These cells had been irradiated in the middle of the S phase. It is assumed that with increasing LET, euchromatic DNA regions are most readily damaged. When the two irradiation depths were compared, it was found that the aberration rate was significantly reduced after irradiation in sulphoguanidine solution at a depth of 30% relative dose. A qualitative assessment showed that fragments made up the highest and bridges the lowest fraction of aberrations, although there were variations in the single values depending on the irradiation conditions and culture media used. It was assumed that sulfoguanidine may have a positive influence on repair processes in damaged DNA, and that this influence depends on the energy spectrum of the irradiation. Furthermore, the possibility of a biochemical mechanism was discussed. (orig./MG) [de

Dose Assessment using Chromosome Aberration Analyses in Human Peripheral Blood Lymphocytes

Energy Technology Data Exchange (ETDEWEB)

Ryu, Tae Ho; Kim, Jin-Hong; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

The healthy five donors were recruited to establish the dose-response calibration curve for chromosomal aberrations by ionizing radiation exposure. Our cytogenetic results revealed that the mean frequency of chromosome aberration increased with increasing radiation dose. In this study, dicentric assay and CBMN assay were compared considering the sensitivity and accuracy of dose estimation. Therefore, these chromosome aberration analyses will be the foundation for biological dosimetric analysis with additional research methods such as translocation and PCC assay. The conventional analysis of dicentric chromosomes in HPBL was suggested by Bender and Gooch in 1962. This assay has been for many years, the golden standard and the most specific method for ionizing radiation damage. The dicentric assay technique in HPBL has been shown as the most sensitive biological method and reliable bio-indicator of quantifying the radiation dose. In contrast, the micronucleus assay has advantages over the dicentric assay since it is rapid and requires less specialized expertise, and accordingly it can be applied to monitor a big population. The cytokinesis-block micronucleus (CBMN) assay is a suitable method for micronuceli measurement in cultured human as well as mammalian cells. The aim of our study was to establish the dose response curve of radiation-induced chromosome aberrations in HPBL by analyzing the frequency of dicentrics and micronuclei.

Increased frequency of spontaneous and X-ray-induced chromosomal aberrations in lymphocytes from neonates and the influence of caffeine

International Nuclear Information System (INIS)

Karsdon, J.; Rijn, J. van; Berger, H.

1989-01-01

The authors have examined lymphocytes from human preterm (PT) and fullterm (FT) babies for an effect of gestational age (GA) on chromosomal aberrations either occurring spontaneously or indiced by treatment with X-rays alone; or with caffeine supplementation in comparison to the lymphocytes of healthy adults. (AD). Per cent of abnormal cells (% Abn) was used as an indicator of chromosome sensitivy to the different treatments. PT babies had significantly higher spontaneous and X-ray-induced % Abn values than AD, but were comparable to FT. After X-iradiation + caffeine the yield of aberrations in any 2 groups was not significantly different. Chromosomal sensitivity may resuult from factors other than GA. This in vitro model may permit study of the mechanisms of chromosomal damage repair and prevention of free radical damage of DNA during the perinatal period. (author). 33 refs.; 1 fig.; 3 tabs

Comment of the paper 'Chromosome aberrations induced by low doses of X-rays in human lymphocytes in vitro'

International Nuclear Information System (INIS)

Merkle, W.; Paretzke, H.G.

1981-01-01

This comment points out some problems in the statistical evaluation of the data of Ziemba-Zoltowska, E. Bocian, O. Rosiek and J. Sablinski (1980) on chromosome aberrations in irradiated human lymphocytes; comments are made on results derived from a an iteratively reweighted least squares procedure instead of the ordinary unweighted least squares method to establish first and second order dose-response curves for dicentric and centric rings. (U.K.)

Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens

International Nuclear Information System (INIS)

Camats, Nuria; Garcia, Francisca; Parrilla, Juan Jose; Calaf, Joaquim; Martin, Miguel; Caldes, Montserrat Garcia

2008-01-01

Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 metaphases from foetal tissues from the foetal offspring of X-irradiated female rats (5 Gy, acute dose) were analysed. The study's results showed that there is radiation-induced genomic instability: the number of aberrant metaphases and the breaks per total metaphases studied increased and were found to be statistically significant (p ≤ 0.05), with regard to the control group. In order to identify how this trans-generational, radiation-induced chromosomal instability could influence the chromosomal behaviour of the offspring of irradiated rat females in front of a chemical agent (aphidicolin), a total of 2481 metaphases were studied. The observed results showed that there is an enhancement of the action of the chemical agent: chromosomal breaks per aberrant metaphases show significant differences (p ≤ 0.05) in the X-ray- and aphidicolin-treated group as regards the aphidicolin-treated group. In conclusion, our findings indicate that there is trans-generational, radiation-induced chromosomal instability in the foetal cells

Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens

Energy Technology Data Exchange (ETDEWEB)

Camats, Nuria [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Garcia, Francisca [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Parrilla, Juan Jose [Servicio de Ginecologia y Obstetricia, Hospital Universitario Virgen de la Arrixaca, 30120 El Palmar, Murcia (Spain); Calaf, Joaquim [Servei de Ginecologia i Obstetricia, Hospital Universitari de la Santa Creu i Sant Pau, 08025 Barcelona (Spain); Martin, Miguel [Departament de Pediatria, d' Obstetricia i Ginecologia i de Medicina Preventiva, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Caldes, Montserrat Garcia [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Barcelona (Spain)], E-mail: Montserrat.Garcia.Caldes@uab.es

2008-04-02

Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 metaphases from foetal tissues from the foetal offspring of X-irradiated female rats (5 Gy, acute dose) were analysed. The study's results showed that there is radiation-induced genomic instability: the number of aberrant metaphases and the breaks per total metaphases studied increased and were found to be statistically significant (p {<=} 0.05), with regard to the control group. In order to identify how this trans-generational, radiation-induced chromosomal instability could influence the chromosomal behaviour of the offspring of irradiated rat females in front of a chemical agent (aphidicolin), a total of 2481 metaphases were studied. The observed results showed that there is an enhancement of the action of the chemical agent: chromosomal breaks per aberrant metaphases show significant differences (p {<=} 0.05) in the X-ray- and aphidicolin-treated group as regards the aphidicolin-treated group. In conclusion, our findings indicate that there is trans-generational, radiation-induced chromosomal instability in the foetal

Symmetrical exchanges between chromosomes induced by irradiation of human lymphocytes with fast neutrons and detected by repeated fluorescence in situ hybridisation

International Nuclear Information System (INIS)

Lukasova, E.; Kozubek, S.; Ryznar, L.; Mareckova, A.; Bartova, E.; Kozubek, M.; Skalnikova, M.; Kroha, V.

1998-01-01

The frequency was studied of exchange aberrations between chromosomes no. 1, 2, 3, 4, 6, 8, 9, 11, 12, 14, 18, and 22 in the first postirradiation mitosis of human lymphocytes irradiated with various doses of neutrons of a mean energy of 7 MeV. Seven repeated hybridizations were carried out. Seven different images were obtained for each mitosis, in which two specific chromosomes were distinguished from the others by red and green fluorescence. The successive images were compared, whereby the frequencies of exchange aberrations between the visualized chromosomes were found. The results show a higher frequency of exchanges between chromosomes 14/8, 14/18, 14/3, 8/3, 8/1, and 8/18. No exchange aberrations occurred between the upper of the chromosomes mentioned and chromosomes 9, 22, 4, or 12. The results suggest that chromosomes 1, 3, 8, 14, and 18 are located in mutual vicinity in the interphase nuclei of lymphocytes. This vicinity seems to be one of the reasons for the spontaneous reciprocal exchanges between chromosome 14 and the remaining chromosomes mentioned (1, 3, 8, 18), characteristic for the malignancy of B-lymphocytes in various types of non-Hodgkin lymphomas

Mechanisms of induction of chromosomal aberrations and their detection by fluorescence in situ hybridization

International Nuclear Information System (INIS)

Natarajan, A.T.

2002-01-01

Recently introduced fluorescence in situ hybridization (FISH) technique employing chromosome specific DNA libraries as well as region specific DNA probes (e.g., centromere, telomere) have helped to analyse chromosomal aberrations in great detail and thus have given some new insights into the mechanisms of induction of chromosomal aberrations. The relative proportion of induction of translocations and dicentrics by ionising radiation was studied in human, mice and Chinese hamster cells. Many of the studies point to the differences between the mechanisms of induction of dicentrics and translocations. Preliminary results obtained in our laboratory using arm specific probes for human chromosomes 1 and 3 indicate that the aberrations between the arms appear to be more than expected on a random basis. By employing telomeric probes the frequencies of interstitial deletions were found to be high and similar to the frequencies of dicentrics both in human and mouse lymphocytes. A recent study with human chromosome specific probes clearly shows variation of sensitivity of chromosomes for the induction of exchange aberrations. Radiation response studies with Chinese hamster cells using telomeric probes, suggest that telomeric sequences, especially interstitial ones appear to be an important factor in the origin of both spontaneous and induced chromosomal aberrations

Damage of chromosoms under irradiation of human blood lymphocytes and development of bystander effect.

Science.gov (United States)

Shemetun, O V

2016-12-01

the research the distribution of radiation induced damages among chromosomes and their bands in irra diated in vitro human blood lymphocytes and in unirradiated bystander cells.Material and methods of research: cultivation of human peripheral blood lymphocytes by semi micromethod D.A. Hungerford, modeling of radiation induced bystander effect in mixed cultures consisting of irradiated in vitro and non irradiated blood lymphocytes from persons of different gender, GTG staining of metaphase chromosomes and their cytogenetic analysis. Break points in chromosomes under the formation of aberrations were identified in exposed in vitro human peripheral blood lymphocytes in doses 0.25 Gy (95 breaks in 1248 cells) and 1.0 Gy (227 breaks in 726 cells) and in non irradiated bystander cells under their joint cultivation with irradiated in vitro human lymphocytes (51 breaks in 1137 cells at irradiation of adjacent populations of lymphocytes in dose 0.25 Gy and 75 breaks in 1321 cells at irradiation of adjacent population of lymphocytes in a dose 1.0 Gy). The distribution of injuries among the chromo somes and their bands was investigated. in radiation exposed in vitro human peripheral blood lymphocytes as well as in bystander cells the fre quency of damaged bands and number of breaks which localized in them exceeded the control value (p chromosomes were damaged according to their relative length. Location of bands with increasing number of breaks coincided with the «hot spots» of chromosome damage following irradiation and fragile sites. More sensitive to damage were G negative euchromatin chromosome bands, in which were localized 82 88 % breaks. Damageability of telomeric regions in the irradiated cells had no significant difference from the control, while in bystander cells was lower than control value (p < 0.05). O. V. Shemetun.

Formation and Expansion of Leukemia-Specific Chromosome Aberrations in Hematopoietic Cells of X-ray Irradiated Mice

International Nuclear Information System (INIS)

Ban, N.; Kai, M.; Kusama, T.

2004-01-01

C3H/He mice develop acute myeloid leukemia (AML) after whole-body irradiation, and typical chromosome 2 deletions are found in the leukemia cells. To investigate a process of the formation and the expansion of the AML-specific deletions, we have examined its frequency in primitive hematopoietic cells that could be the target of the leukemogenesis. Male C3H/He mice were exposed to 3Gy x-rays and sacrificed after certain periods of time. Bone marrow cells were collected from the femora and a single-cell suspension from each animal was divided into two parts. One part of the cell suspension was cultured in methylcellulose medium and metaphase spreads were prepared from each growing colony. The other part was sorted to obtain Lin+ and Lin Scal cells and those cells were scored with FISH for the AML-specific deletions. Karyotyping of the cultured cells detected signs of the delayed chromosomal instability, but an aberration involving chromosome 2 has not been found so far. FISH to the sorted cells, however, revealed the ANL-specific deletions could be produced in the primitive hematopoietic cells as an early event of radiation exposure. (Author) 16 refs

Adaptive responses on chromosome aberration and DNA breakage of peripheral lymphocytes from workers exposed to thorium and rare earth mixed dust in Baotou steel plant

International Nuclear Information System (INIS)

Liu Qingjie; Feng Jiangbing; Lu Xue; Chen Deqing; Lv Huimin; Su Xu; Liu Yufei; Jia Kejun

2008-01-01

Objective: To explore if the occupational exposure to low dose thorium could induce adaptive response in peripheral lymphocytes. Methods: 40 individuals, who exposed to thorium and rare earth mixed dust (exposure group) or control in Baotou Steel Plant, were selected, and chromosome aberrations were analyzed. Then the peripheral blood samples were irradiated in vitro with 2 Gy 60 Co γ-rays, and unstable chromosome aberration or DNA stand breakage analysis using single cell gel electrophoresis was performed. Results: The dicentrics before 2 Gy exposure in exposure group was higher than that in control (P>0.05). But the dicentrics after 2 Gy exposure in exposure group was lower than that in control, but not significantly (P >0.05). The tricentrics in exposure group was significantly lower than that in control (U=3.1622, 0.001< P<0.002). The DNA strand breakage in control group was significantly higher than that in exposure group (t=25, P<0.001). Conclusions: Occupational exposure to low dose thorium could induce the adaptive response on chromosome aberration and DNA strand breakage in peripheral lymphocytes. (authors)

Biological dosimetry: chromosomal aberration analysis for dose assessment

International Nuclear Information System (INIS)

1986-01-01

In view of the growing importance of chromosomal aberration analysis as a biological dosimeter, the present report provides a concise summary of the scientific background of the subject and a comprehensive source of information at the technical level. After a review of the basic principles of radiation dosimetry and radiation biology basic information on the biology of lymphocytes, the structure of chromosomes and the classification of chromosomal aberrations are presented. This is followed by a presentation of techniques for collecting blood, storing, transporting, culturing, making chromosomal preparations and scaring of aberrations. The physical and statistical parameters involved in dose assessment are discussed and examples of actual dose assessments taken from the scientific literature are given

Effects of Spirulina platensis on DNA damage and chromosomal aberration against cadmium chloride-induced genotoxicity in rats.

Science.gov (United States)

Aly, Fayza M; Kotb, Ahmed M; Hammad, Seddik

2018-04-01

Todays, bioactive compounds extracted from Spirulina platensis have been intensively studied for their therapeutical values. Therefore, in the present study, we aimed to evaluate the effects of S. platensis extract on DNA damage and chromosomal aberrations induced by cadmium in rats. Four groups of male albino rats (n = 7 rats) were used. The first group served as a control group and received distilled water. The second group was exposed intraperitoneally to cadmium chloride (CdCl 2 ) (3.5 mg/kg body weight dissolved in 2 ml distilled water). The third group included the rats that were orally treated with S. platensis extract (1 g/kg dissolved in 5 ml distilled water, every other day for 30 days). The fourth group included the rats that were intraperitoneally and orally exposed to cadmium chloride and S. platensis, respectively. The experiment in all groups was extended for 60 days. The results of cadmium-mediated toxicity revealed significant genetic effects (DNA fragmentation, deletion or disappearance of some base pairs of DNA, and appearance of few base pairs according to ISSR-PCR analysis). Moreover, chromosomes showed structural aberrations such as reduction of chromosomal number, chromosomal ring, chromatid deletions, chromosomal fragmentations, and dicentric chromosomes. Surprisingly, S. platensis extract plus CdCl 2 -treated group showed less genetic effects compared with CdCl 2 alone. Further, S. platensis extract upon CdCl 2 toxicity was associated with less chromosomal aberration number and nearly normal appearance of DNA fragments as indicated by the bone marrow and ISSR-PCR analysis, respectively. In conclusion, the present novel study showed that co-treatment with S. platensis extract could reduce the genotoxic effects of CdCl 2 in rats.

Research on Spontaneously Emerged Chromosomal Aberrations in the Periphery Blood Lymphocytes in Cattle (‘Buša’ Breed

Directory of Open Access Journals (Sweden)

Danica Hasanbašić

2007-11-01

Full Text Available Knowledge of spontaneous aberrations, namely, of their frequency in non-irradiated cells is of paramount importance not only in cytogenetic research, but also in contemporary animal production.The paper deals with research on spontaneously emerged chromosomal aberrations in the peripheral blood lymphocytes in the cattle of ‘Buša’ breed.To obtain metaphase chromosomes the conventional method of lymphocyte cultivation was used, albeit slightly modified and adapted to the examined animals and the laboratory conditions.The research findings indicate that a certain percent of spontaneously emerged chromosomal aberrations of chromatid type (gap and break have been found in the peripheral blood lymphocytes in the cattle of ‘Buša’ breed.

Induction and persistence of multicentric chromosomes in cultured human peripheral blood lymphocytes following high-dose gamma irradiation

International Nuclear Information System (INIS)

Suto, Yumiko; Hirai, Momoki; Akiyama, Miho; Nakagawa, Takashi; Tominaga, Takako; Suzuki, Toshikazu; Sugiura, Nobuyuki; Yuki, Masanori; Nakayama, Fumiaki

2012-01-01

Among radiation-induced chromosome aberrations, multicentric chromosomes, as represented by dicentric chromosomes (dicentrics), are regarded as sensitive and specific biomarkers for assessing radiation dose in the 0 to 5 Gy range. The objective of this study was to characterize chromosome aberrations induced in vitro by a higher dose of radiation. Peripheral blood lymphocytes were exposed to 15 Gy gamma rays at a dose rate of 0.5 Gy/min and harvested at 48, 50, 52, 54, 56 and 72 h. The first mitotic peak appeared at 52-54 h, showing about a 6 h mitotic delay as compared with nonirradiated control cultures. Cell-cycle analysis of parallel and simultaneous cultures by sister-chromatid differentiation staining suggests that metaphase cells examined in 48-56 h cultures were in the first mitosis after culture initiation. The mean dicentric equivalent counts ranged from 9.0 to 9.3 in consecutively harvested cultures with no significant differences among them. At 72 h, about 20% of dividing cells were tetraploid, persisting with faithfully replicated unstable chromosome aberrations. The non-random distribution of replicated chromosome pairs, deduced from multicolor fluorescence in situ hybridization analysis, led us to surmise that the predominant mechanism underlying the induction of tetraploid cells is endoreduplication. These findings suggest that a high-dose in vitro irradiation applied to peripheral blood lymphocytes may affect on the replication process, in addition to structural chromosome damage. (author)

Towards a cumulative biological dosimeter based on chromosome painting and digital image analysis

International Nuclear Information System (INIS)

Popp, S.; Cremer, C.; Remm, B.; Hausmann, M.; Cremer, T.; Luehrs, H.; Kaick, G. van

1990-01-01

An approach for a long-term (cumulative) biological dosimeter is described, based on the idea that stem cells with irradiation-induced reciprocal translocations and their progeny would neither lose nor gain genetic material and thus should retain the same proliferative potential as non-irradiated cells. Rapid detection of chromosome translocations has become possible in irradiated human lymphocytes by a newly developed fluorescent in situ hybridization method called 'chromosome painting'. We have used this approach to score chromosome aberrations, including translocation events, in over 8000 chromosomes painted in lymphocytes from two patients exposed to an X-ray contrast medium containing Th-232 and from two age-matched control persons. The percentage of both the total fraction of aberrant painted chromosomes and of translocations was found significantly higher in exposed patients. A program was developed which can automatically determine the number of normal and aberrant painted chromosomes and classify evaluated cells as 'normal' or 'aberrant' within 1 to 2 seconds. (orig.) [de

Chromosome aberration induction in human diploid fibroblast and epithelial cells

International Nuclear Information System (INIS)

Scott, D.

1986-01-01

The relative sensitivity of cultured human fibroblasts and epithelial cells to radiation-induced chromosomal aberrations was investigated. Lung fibroblast and kidney epithelial cells from the same fetus were compared, as were skin fibroblasts and epithelial keratinocytes from the same foreskin sample. After exposure of proliferating fetal cells to 1.5 Gy X-rays there was a very similar aberration yield in the fibroblasts and epithelial cells. Observations of either little or no difference in chromosomal sensitivity between human fibroblasts and epithelial cells give added confidence that quantitative cytogenetic data obtained from cultured fibroblasts are relevant to the question of sensitivity of epithelial cells which are the predominant cell type in human cancers. (author)

Chromosomal aberrations in children exposed to diagnostic x-rays

International Nuclear Information System (INIS)

Nordenson, I.; Beckman, G.; Beckman, L.; Lemperg, R.

1980-01-01

Among children who have received high x-ray doses congenital dislocation of the hip joint is the predominating diagnosis. In a series of 9 children who had received high x-ray doses (8 with luxation of the hip joint and one with achondroplasia) a significant increase of chromosomal aberrations was found. The increase concerned mainly chromosome type aberrations. The shorter the time since the last x-ray investigation the higher was the frequency of chromosome type aberrations. (author)

New type of chromosomal aberrations in microspores of Tradescancia Paludosa in flight experiments on board of space satelites

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Delone, N L; Antipov, V V; Parfenov, G P

1986-01-01

A new type of chromosomal aberrations - complex nonreciprocal translocations accompanied by spherical fragments, is opened. The results of 30 variants of tests are investigated to establish what factor particularly causes new type of chromosomal aberrations. The experiments have been carried out on boards the space satelites: ''Vostok 3, 4, 5, 6'', ''Voskhod'', ''Kosmos 110'', ''Zond 6, 7'', ''Kosmos 368''. All type of aberrations have been recorded. It is supposed that a new type of aberrations depends on the effect of the sum of dynamic factors. At the same time these aberrations are not the background and escape it by separate bright bursts being independent on the effect of take-off, landing and time of an object staying in weightlessness. There is a type of irradiation causing a special type of aberrations.

New type of chromosomal aberrations in microspores of Tradescancia Paludosa in flight experiments on board of space satelites

International Nuclear Information System (INIS)

Delone, N.L.; Antipov, V.V.; Parfenov, G.P.

1986-01-01

A new type of chromosomal aberrations - complex nonreciprocal translocations accompanied by spherical fragments, is opened. The results of 30 variants of tests are investigated to establish what factor particularly causes new type of chromosomal aberrations. The experiments have been carried out on boards the space satelites: ''Vostok 3, 4, 5, 6'', ''Voskhod'', ''Kosmos 110'', ''Zond 6, 7'', ''Kosmos 368''. All type of aberrations have been recorded. It is supposed that a new type of aberrations depends on the effect of the sum of dynamic factors. At the same time these aberrations are not the background and escape it by separate bright bursts being independent on the effect of take-off, landing and time of an object staying in weightlessness. There is a type of irradiation causing a special type of aberrations

Effect of 2-mercaptopropionylglycine (MPG) on the radiation-induced chromosome aberrations in the bone marrow of mice

International Nuclear Information System (INIS)

Uma, D.P.; Gupta, R.

1984-01-01

The radioprotective effect of MPG, a SH compound used clinically as detoxicating agent, was investigated in vivo on adult whole-body exposed mice to 3 Gy of 60 Co radiation 15 to 20 min after a single i.p. injection of MPG. Animals pretreated with colchicine were autopsied at various intervals from 2 to 28 days and bone marrow metaphases were scored. Significantly less number of cells were found to carry aberrations in the MPG-treated animals at 24 hr as compared to the non-drug treated irradiated ones. However, at all the other earlier and later intervals, both groups of animals showed approximately the same frequency of aberrant cells. It appears that MPG protection to the chromosome is at the reparation stage rather than at the initial stage of breakage. (author)

Frequency of unstable chromosome aberrations in peripheral lymphocytes of women with breast cancer treated with radiotherapy

International Nuclear Information System (INIS)

Espinoza Jeria, Marcela; Castro Acuna, Daniel

2003-01-01

This study proposes to obtain information about the behavior of the frequency and distribution of radiation induced lymphocyte dicentric chromosome aberrations with therapeutic doses in women with breast cancer treated only with radiotherapy, about which there are no existing works in Chile. Blood samples were taken from 6 women volunteers included in the study, with their informed consent, treated in the Fundacion Arturo Lopez Perez, aged 24 to 65 years old, without prior or parallel chemotherapy, nor prior radiotherapy. Three peripheral blood samples were taken from each patient in 0, 16.2 and 43.2 Gy doses. The lymphocytes obtained from each sample were cultivated using the micro-culture technique following the protocol in IAEA Technical Report No. 405, 2001. The samples were evaluated under a microscope and the unstable chromosome aberrations for lymphocytes were counted. A total of 500 cells per sample was evaluated in most cases, which were distributed depending on the number of aberrations that they had. The results were analyzed by treatment dose for each of the study patients, using the Papworth u test, Dolphin's 'Contaminated Poisson' method and Sasaki's 'QDR'. Great variations were observed in the frequency distribution of aberrations among the patients studied, which could be due to the influence of factors related to the patients' partial irradiations (C.Wood)

Comparison of hprt variant frequencies and chromosome aberration frequencies in lymphocytes from radiotherapy and chemotherapy patients: A prospective study

International Nuclear Information System (INIS)

Ammenheuser, M.M.; Au, W.W.; Whorton, E.B. Jr.; Belli, J.A.; Ward, J.B. Jr.

1991-01-01

The autoradiographic 6-thioguanine-resistant mutant lymphocyte assay and a chromosome aberration assay were used to determine the time-course of appearance and persistence of elevated frequencies of hprt variants and dicentric chromosomes in patients receiving x-irradiation therapy. The hprt mutation assays were done with frozen/thawed lymphocytes isolated from aliquots of the same blood samples used for the chromosome aberration assays. Five multiple sclerosis patients were also studied before and at 2 and 4 wk intervals after treatment with monthly i.v. doses of 750 mg/m 2 of cyclophosphamide (CP). There were no significant elevations in chromosome aberrations at these post-treatment sample times. The results demonstrate the complementary nature of these two human monitoring assays and emphasize the importance of careful selection of optimal sampling times

Modification of chromosomal aberration and polyploidy by combined treatment with x-rays and colchicine in Trichosanthes anguina

International Nuclear Information System (INIS)

Datta, S.K.; Basu, R.K.

1978-01-01

Mitosis in root tip cells of T. anguina after treatment of seeds with X-rays, colchicine and in combination of the two was studied. X-irradiation resulted in cells with chromosomal aberrations, which increased with increase in doses. With increase in colchicine concentrations there was decrease in diploid cells with consequent increase in polyploid cells. Post-irradiation colchicine treatment resulted in both aberrant and polyploid cells but their frequencies were less than separate treatment with X-rays and colchicine respectively. (author)

Frequencies of X-ray and fast neutron induced chromosome translocations in human peripheral blood lymphocytes as detected by in situ hybridization using chromosome specific DNA libraries

International Nuclear Information System (INIS)

Natarajan, A.T.; Darroudi, F.; Vermeulen, S.; Wiegant, J.

1992-01-01

DNA libraries of six human chromosomes were used to detect translocations in human lymphocytes induced by different doses of X-rays and fast neutrons. Results show that with X-rays, one can detect about 1.5 to 2.0 fold more translocations in comparison to dicentrics, whereas following fast neutron irradiation, the difference between these two classes of aberrations are significantly different at high doses. In addition, triple fluorescent in situ hybridization technique was used to study the frequencies of radiation-induced translocations involving a specific chromosome. Chromosome number 1 was found to be involved in translocations more frequently than chromosomes number 2, 3, 4, 8 and X. (author). 10 refs., 1 fig., 2 tabs

Mutations and chromosomal aberrations

International Nuclear Information System (INIS)

Kihlman, B.A.

1977-01-01

The genetic changes of mutations and chromosomal aberrations are discussed. The consequences of both depend not only on the type of genetic change produced but also on the type of cell that is affected and on the development stage of the organism. (C.F.)

Chromosomal aberrations in subjects exposed to ionizing radiation

International Nuclear Information System (INIS)

Jovicic, D.; Milacic, S.; Kovacevic, R.; Tanaskovic, I.

2006-01-01

Occupational exposure is particularly delicate because of chronic exposure to low doses of ionizing radiation and its cumulative effect, where it is important to consider the biological response of body to given conditions of exposure. The objective of this study was the observation of the recovery of the DNA damages in subjects working in the radiation area in two different intervals.Group I, consisting of 30 subjects, was exposed to ionizing radiation and unstable chromosomal aberrations were identified. Group II included the same, re-examined subjects (30) 9 months later. It was verified that 5 (16.67%) subjects still had unstable chromosomal aberrations, although they had been excluded from radiation area Controls groups (C) consisted of 64 subjects that were not exposed to mutagenic agents.The comparison of the control group with the two studied groups revealed the reduction of the unstable aberrations (p<0.05). The total effective doses, which increased with the years spent in radiation area, reflected the yield of chromosomal aberrations. The presence of chromosomal aberrations in some subjects, after the exclusion from the ionising radiation exposure, suggests that the time needed for the recovery of the DNA damages is different, which indicates the individual differences in radiosensitivity as well as different of the reparatory cellular response. (author)

Chromosome aberration assays in Allium

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Grant, W.F.

1982-01-01

The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

The induction of chromosomal aberrations by X irradiation during S-phase in cultured diploid Syrian hamster fibroblasts

International Nuclear Information System (INIS)

Savage, J.R.K.; Bhunya, S.P.

1980-01-01

The induction of chromosomal aberrations by 4.0 Gy of 250 kV X-rays in cell throughout S-phase has been investigated in untransformed diploid Syrian hamster fibroblasts. Using a method of subdividing S into catologically defined stages (on the basis of replication band patterns displayed after brome-deoxyuridine incorporation) it is shown that: (1) This dose does not perturb, measurable, the intracellular programme of synthesis at the chromosome band level, so that the cell classification criteria remain valid after radiation. (2) Mitotic delay and perturbation appears to be less for cells in very early S, but there is no evidence of a massive cell mixing of S cells. (3) S-phase is, in general, much less sensitive to aberration induction at all sub-phases than G 2 . (4) Both chromosome and chromatid-type aberrations are found in pre- S and S cells, but chromatid-types predominate in the latter at all sub-phases. (5) The frequency of chromatid-types, especially interchanges falls in eraly. (orig.)

The effect of track structure on the induction of chromosomal aberrations in murine cells

Science.gov (United States)

Durante, M.; Cella, L.; Furusawa, Y.; George, K.; Gialanella, G.; Grossi, G.; Pugliese, M.; Saito, M.; Yang, T. C.

1998-01-01

PURPOSE: To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. MATERIALS AND METHODS: Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. RESULTS: Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. CONCLUSIONS: Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

Stage-specific damage to synaptonemal complexes and metaphase chromosomes induced by X rays in male mouse germ cells

International Nuclear Information System (INIS)

Backer, L.C.; Sontag, M.R.; Allen, J.W.

1991-01-01

Synaptonemal complexes (SCs) reveal mutagen-induced effects in germ cell meiotic chromosomes. The study was aimed at characterizing relationships between SC and metaphase I chromosome damage following radiation exposure at various stages of spermatogenesis. Male mice were irradiated with doses of 0, 2, or 4 Gy, and spermatocytes were harvested at times consistent with earlier exposures as spermatogonial stem cells, preleptotene cells (premeiotic DNA synthesis), or meiotic prophase cells. After stem-cell exposure, twice as many rearrangements were observed in SCs as in metaphase I chromosomes. Irradiation during premeiotic DNA synthesis resulted in dose-related increases in SC breakage and rearrangements (including novel forms) and in metaphase chromosomal aberrations. Following prophase exposure, various types and levels of SC and metaphase damage were observed. Irradiation of zygotene cells led to high frequencies of chromosome multivalents in metaphase I without a correspondingly high level of damage in preceding prophase SCs. Thus, irradiation of premeiotic and meiotic cells results in variable relationships between SC and metaphase chromosome damage

Effects of alpha-particles on survival and chromosomal aberrations in human mammary epithelial cells

Science.gov (United States)

Durante, M.; Grossi, G. F.; Gialanella, G.; Pugliese, M.; Nappo, M.; Yang, T. C.

1995-01-01

We have studied the radiation responses of a human mammary epithelial cell line, H184B5 F5-1 M/10. This cell line was derived from primary mammary cells after treatment with chemicals and heavy ions. The F5-1 M/10 cells are immortal, density-inhibited in growth, and non-tumorigenic in athymic nude mice and represent an in vitro model of the human epithelium for radiation studies. Because epithelial cells are the target of alpha-particles emitted from radon daughters, we concentrated our studies on the efficiency of alpha-particles. Confluent cultures of M/10 cells were exposed to accelerated alpha-particles [beam energy incident at the cell monolayer = 3.85 MeV, incident linear energy transfer (LET) in cell = 109 keV/microns] and, for comparison, to 80 kVp x-rays. The following endpoints were studied: (1) survival, (2) chromosome aberrations at the first postirradiation mitosis, and (3) chromosome alterations at later passages following irradiation. The survival curve was exponential for alpha-particles (D0 = 0.73 +/- 0.04 Gy), while a shoulder was observed for x-rays (alpha/beta = 2.9 Gy; D0 = 2.5 Gy, extrapolation number 1.6). The relative biological effectiveness (RBE) of high-LET alpha-particles for human epithelial cell killing was 3.3 at 37% survival. Dose-response curves for the induction of chromosome aberrations were linear for alpha-particles and linearquadratic for x-rays. The RBE for the induction of chromosome aberrations varied with the type of aberration scored and was high (about 5) for chromosome breaks and low (about 2) for chromosome exchanges.(ABSTRACT TRUNCATED AT 250 WORDS).

Chromosome aberration model combining radiation tracks, chromatin structure, DSB repair and chromatin mobility

International Nuclear Information System (INIS)

Friedland, W.; Kundrat, P.

2015-01-01

The module that simulates the kinetics and yields of radiation-induced chromosome aberrations within the biophysical code PARTRAC is described. Radiation track structures simulated by Monte Carlo methods are overlapped with multi-scale models of DNA and chromatin to assess the resulting DNA damage. Spatial mobility of individual DNA ends from double-strand breaks is modelled simultaneously with their processing by the non-homologous end-joining enzymes. To score diverse types of chromosome aberrations, the joined ends are classified regarding their original chromosomal location, orientation and the involvement of centromeres. A comparison with experimental data on dicentrics induced by gamma and alpha particles shows that their relative dose dependence is predicted correctly, although the absolute yields are overestimated. The critical model assumptions on chromatin mobility and on the initial damage recognition and chromatin remodelling steps and their future refinements to solve this issue are discussed. (authors)

Chromosome aberration analysis based on a beta-binomial distribution

International Nuclear Information System (INIS)

Otake, Masanori; Prentice, R.L.

1983-10-01

Analyses carried out here generalized on earlier studies of chromosomal aberrations in the populations of Hiroshima and Nagasaki, by allowing extra-binomial variation in aberrant cell counts corresponding to within-subject correlations in cell aberrations. Strong within-subject correlations were detected with corresponding standard errors for the average number of aberrant cells that were often substantially larger than was previously assumed. The extra-binomial variation is accomodated in the analysis in the present report, as described in the section on dose-response models, by using a beta-binomial (B-B) variance structure. It is emphasized that we have generally satisfactory agreement between the observed and the B-B fitted frequencies by city-dose category. The chromosomal aberration data considered here are not extensive enough to allow a precise discrimination between competing dose-response models. A quadratic gamma ray and linear neutron model, however, most closely fits the chromosome data. (author)

Effect of post-treatments with caffeine during G2 on the frequencies of chromosome-type aberrations produced by X-rays in human lymphocytes during G0 and G1

International Nuclear Information System (INIS)

Tanzarella, C.; De Salvia, R.; Degrassi, F.; Palitti, F.; Andersson, H.C.; Hansson, K.; Kihlman, B.A.

1986-01-01

Human lymphocytes were irradiated with X-rays in G 0 and G 1 , grown in the presence of 5-bromodeoxyuridine, and harvested at different times from 48 to 80 h after stimulation. Some cultures were exposed to 2.5-5 mM caffeine during the last 3 h before harvesting. The frequencies of chromosome-type aberrations were scored in first division (M 1 ) metaphases. The post-treatment with caffeine increased the frequencies of mitoses and chromosome-type aberrations in irradiated cultures. The results suggest that cells carrying chromosome-type aberrations are delayed in G 2 and that caffeine increases the frequencies of aberrations in dividing cells by removing this G 2 -block. (author)

Radioprotection by caffeine pre-treatment and post-treatment in the bone marrow chromosomes of mice given whole-body γ-irradiation

International Nuclear Information System (INIS)

Farooqi, Z.; Kesavan, P.C.

1992-01-01

The effect of caffeine given as pre- and post-treatment in mice exposed to whole-body γ-irradiation (1.5 Gy 60 Co γ-rays) was studied. The pre-treatment was either acute or chronic. The acute dose (5 mg/kg and 15 mg/kg body weight) was in the form of an injection given intraperitoneally, 30 min before irradiation. The chronic administration was in the form of caffeine solution (4.208x10 -3 M and 7.72x10 -4 M) contained in drinking water for 5 weeks prior to radiation exposure. The acute pre-treatment with caffeine reduced the radiation-induced frequency of chromosomal aberrations discernibly, whereas chronic pre-treatment afforded a much more significant degree of radioprotection. The caffeine post-treatment (5 mg/kg and 15 mg/kg body weight) was given in the form of an intraperitoneal injection to the mice immediately following whole-body γ-irradiation. It is noted that both post-treatment concentrations of caffeine also significantly reduced the frequency of chromosomal aberrations induced by γ-rays. These data are briefly discussed in terms of possible mechanistic considerations. (author). 33 refs.; 3 tabs

Radioprotection by caffeine pre-treatment and post-treatment in the bone marrow chromosomes of mice given whole-body [gamma]-irradiation

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Farooqi, Z.; Kesavan, P.C. (Jawaharlal Nehru Univ., New Delhi (India). School of Life Sciences)

1992-10-01

The effect of caffeine given as pre- and post-treatment in mice exposed to whole-body [gamma]-irradiation (1.5 Gy [sup 60]Co [gamma]-rays) was studied. The pre-treatment was either acute or chronic. The acute dose (5 mg/kg and 15 mg/kg body weight) was in the form of an injection given intraperitoneally, 30 min before irradiation. The chronic administration was in the form of caffeine solution (4.208x10[sup -3] M and 7.72x10[sup -4] M) contained in drinking water for 5 weeks prior to radiation exposure. The acute pre-treatment with caffeine reduced the radiation-induced frequency of chromosomal aberrations discernibly, whereas chronic pre-treatment afforded a much more significant degree of radioprotection. The caffeine post-treatment (5 mg/kg and 15 mg/kg body weight) was given in the form of an intraperitoneal injection to the mice immediately following whole-body [gamma]-irradiation. It is noted that both post-treatment concentrations of caffeine also significantly reduced the frequency of chromosomal aberrations induced by [gamma]-rays. These data are briefly discussed in terms of possible mechanistic considerations. (author). 33 refs.; 3 tabs.

Chromatin dynamics during cell cycle mediate conversion of DNA damage into chromatid breaks and affect formation of chromosomal aberrations: Biological and clinical significance

International Nuclear Information System (INIS)

Terzoudi, Georgia I.; Hatzi, Vasiliki I.; Donta-Bakoyianni, Catherine; Pantelias, Gabriel E.

2011-01-01

The formation of diverse chromosomal aberrations following irradiation and the variability in radiosensitivity at different cell-cycle stages remain a long standing controversy, probably because most of the studies have focused on elucidating the enzymatic mechanisms involved using simple DNA substrates. Yet, recognition, processing and repair of DNA damage occur within the nucleoprotein complex of chromatin which is dynamic in nature, capable of rapid unfolding, disassembling, assembling and refolding. The present work reviews experimental work designed to investigate the impact of chromatin dynamics and chromosome conformation changes during cell-cycle in the formation of chromosomal aberrations. Using conventional cytogenetics and premature chromosome condensation to visualize interphase chromatin, the data presented support the hypothesis that chromatin dynamic changes during cell-cycle are important determinants in the conversion of sub-microscopic DNA lesions into chromatid breaks. Consequently, the type and yield of radiation-induced chromosomal aberrations at a given cell-cycle-stage depends on the combined effect of DNA repair processes and chromatin dynamics, which is cell-cycle-regulated and subject to up- or down-regulation following radiation exposure or genetic alterations. This new hypothesis is used to explain the variability in radiosensitivity observed at various cell-cycle-stages, among mutant cells and cells of different origin, or among different individuals, and to revisit unresolved issues and unanswered questions. In addition, it is used to better understand hypersensitivity of AT cells and to provide an improved predictive G2-assay for evaluating radiosensitivity at individual level. Finally, experimental data at single cell level obtained using hybrid cells suggest that the proposed hypothesis applies only to the irradiated component of the hybrid.

Modifying effect of 5-fluoro-2-deoxyuridine and thymidine at G1 phase on radiation and chemically induced chromosome rearrangement

International Nuclear Information System (INIS)

Azatyan, R.A.; Voskanyan, A.Z.; Avakyan, V.A.; Akif'ev, A.P.

1978-01-01

The yield of structural chromosome mutations induced in Crepis capillaris seeds by X-rays and nitrogen mustard was studied as a function of treatment (at G 1 phase) with an inhibitor of unscheduled DNA synthesis, 5-fluoro-2-deoxyuridine (FdU), and its antagonist, thymidine. Air-dry seeds were irradiated at 10 krad and immediately placed in aqueous solutions of FdU, thymidine, or FdU + thymidine. Ionizing radiation induced only chromosome exchanges in the seeds. When EdU was used, the number of chromosome exchanges was the same although the fraction of simple and isolocus deletions was significantly greater than additive. The effect of FdU was manifested only after 10-hour incubation of the cells. Thymidine alone did not appreciably alter the frequency of radiation-induced aberrations. At the same time, the FdU + thymidine combination decreased the mutation yield i.e. was protective. Frequencies of the chromosome aberration in this experiment were the same as in the control

Disruption of Maternal DNA Repair Increases Sperm-DerivedChromosomal Aberrations

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Marchetti, Francesco; Essers, Jeroun; Kanaar, Roland; Wyrobek,Andrew J.

2007-02-07

The final weeks of male germ cell differentiation occur in aDNA repair-deficient environment and normal development depends on theability of the egg to repair DNA damage in the fertilizing sperm. Geneticdisruption of maternal DNA double-strand break repair pathways in micesignificantly increased the frequency of zygotes with chromosomalstructural aberrations after paternal exposure to ionizing radiation.These findings demonstrate that radiation-induced DNA sperm lesions arerepaired after fertilization by maternal factors and suggest that geneticvariation in maternal DNA repair can modulate the risk of early pregnancylosses and of children with chromosomal aberrations of paternalorigin.

Aberrations of chromosome 8 in myelodysplastic syndromes: Clinical and biological significance

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Marisavljević Dragomir

2006-01-01

Full Text Available Introduction: Rearrangements of any single chromosome in human karyotype have been reported in patients with pMDS. Objective: To examine the role of aberrations of chromosome 8 in pathogenesis, clinical presentation and progression of myelodysplastic syndromes. Method: Cytogenetic analysis of bone marrow cells was carried out by direct method and by means of 24- and/or 48-hour unstimulated cell culture. Chromosomes were obtained by modified method of HG-bands. Results: On presentation, 109 out of 271 successfully karyotyped patients (40,2% had abnormal karyotypes. Among them, 22 patients (10.9% had aberrations of chromosome 8. Ten patients had trisomy 8 as "simple" aberration whilst additional three cases had trisomy 8 included in "complex" karyotypes (≥3 chromosomes. Cases with constitutional trisomy 8 mosaicism (CT8M were excluded using the chromosome analyses of PHA-stimulated blood cultures. On the contrary, monosomy (seven patients or deletion of chromosome 8 (two patients were exclusively found in "complex" karyotypes. During prolonged cytogenetic follow-up, trisomy 8 was not recorded in evolving karyotypes. In contrast, trisomy 8 disappeared in two cases during subsequent cytogenetic studies, i.e. 23 and 72 months from diagnosis, accompanied in one patient with complete hematological remission. No difference regarding age, sex, cytopenia, blood and marrow blast count or response to treatment was found between patients with trisomy 8 as the sole aberration compared to those with normal cytogenetics. Median survival of patients with trisomy 8 as the sole aberration was 27 months, as compared to 32 months in patients with normal cytogenetics (p=0.468, whilst median survival of patients with aberrations of chromosome 8 included in "complex" karyotypes was only 4 months. Conclusion: Aberrations of chromosome 8 are common in patients with pMDS. The presence of a clone with trisomy 8 is not always the sign of disease progression or poor

Effect of pretreatment with venom of Apis mellifera bees on the yield of gamma-ray induced chromosome aberrations in human blood lymphocytes

International Nuclear Information System (INIS)

Varanda, E.A.; Takahashi, C.S.

1993-01-01

Venom of the honey bee Apis mellifera induced a protective effect against the induction of dicentric chromosomes by gamma radiation (2.0 Gy) in human peripheral blood lymphocytes when the cultures were treated with 0.00015 μl venom/1 ml medium 6 h before irradiation. In cultures to which the venom was added immediately before irradiation with 0.25, 1.0 and 2.0 Gy, no significant differences in number of dicentric chromosomes induced was observed when compared to cultures submitted to irradiation only. The venom did not induce clastogenic effects nor did it increase the frequency of sister chromatid exchanges. (author)

Chromosome aberrations in human lymphocytes after irradiation with NIRS-cyclotron fast neutrons in vitro

International Nuclear Information System (INIS)

Muramatsu, Susumu; Maruyama, Takashi

1977-01-01

The dose-response relationships for inducing chromosome aberrations (dicentrics) in human lymphocytes were studied by whole-blood microculture following in vitro exposures at various doses either 200 kVp x-rays or NIRS-cyclotron fast neutrons. The yields of dicentrics induced were dependent on the exposure dose of two types of radiations between 48 to 384 rad and 25 to 400 rad by x-rays and fast neutrons, respectively. The dicentrics yields gave the best fit to the linear quadratic function Y=αD + βD 2 ; namely Y sub(X)=3.66 x 10 -4 D + 8.01 x 10 -6 D 2 for x-rays and Y sub(N)=28.90 x 10 -4 D + 4.04 x 10 -6 D 2 for fast neutrons. The RBE value of NIRS-cyclotron fast neutrons versus 200 kVP x-rays decreased with increasing neutron doses, for example from 2.3 at 50 rad to 1.2 at doses up to 300 rad. (auth.)

Detection of genomic instability in α-irradiated and bystander human fibroblasts

International Nuclear Information System (INIS)

Ponnaiya, B.; Jenkins-Baker, G.; Bigelow, A.; Marino, S.; Geard, C.R.

2003-01-01

Full text: We have previously demonstrated a radiation induced bystander effect using novel co-culturing techniques where irradiated and bystander cells were cultured on two surfaces of mylar separated by media. Here we present data from experiments designed to investigate the induction of chromosomal aberrations in irradiated and bystander fibroblasts using these co-culturing techniques. Immortalized fibroblasts ((BJ1-tert) were cultured on both mylar surfaces and cells on one side were irradiated with 0.1 or 1 Gy -particles (an average of 1 and 10 particles per cell nucleus respectively), the two sides were separated 1 hour post irradiation and analyzed for chromosomal aberrations using standard Giemsa staining at either immediate or delayed time points. At 24-30 hours post irradiation, frequencies of chromosomal aberrations in irradiated populations were increased in a dose dependent manner as expected. Populations that received 0.1 and 1 Gy had 0.3 and 1.3 aberrations/cell; these aberrations were almost exclusively chromosome type aberrations. In contrast, at these times bystander populations had elevated yields of chromatid-type aberrations. When assayed at later times (15-20 population doublings post irradiation) both irradiated and bystander cells demonstrated elevated frequencies of chromatid-type aberrations. Frequencies in the irradiated populations ranged from 0.07 to 0.09 aberrations/ cell at 15 doublings, and 0.09-0.14/cell at 20 doublings, with no apparent dose response. Aberration frequencies in the bystander populations were between 0.08-0.14 per cell at the delayed time points assayed. Interestingly, the chromatid-type aberrations observed immediately post irradiation in the bystander cells, and at later times in both the irradiated and bystander populations were qualitatively similar to those previously observed at delayed times in neutron irradiated epithelial cells. Furthermore, there was a similar lack of a dose response in those studies as

Studies on the effects of radiation on enzyme activity and chromosome in mammals (Mus musuculus)

International Nuclear Information System (INIS)

Kim, J.B.; Lee, K.S.; Kim, Y.J.

1982-01-01

From the results of many researches in radiation biology, it is well known that the radiation induces gene mutation, aberration of chromosome which is a carrier of genes and the increase or decrease of enzyme activities in living organisms. However, the frequency of chromosomal aberration or the degree of enzyme activities according to the animal's age when they are irradiated with radiation and time pass after irradiation are known a little if any. From these viewpoints, the research on the frequencies of chromosomal aberrations in bone marrow cells and the degree of activities of glucose-6-phosphate dehydrogenase in liver, kidney and brain, and isocitrate dehydrogense in kidney and brain of mouse has been carried out according to the mice age when they are irradiated with 200 rad of whole body irradiation. The chromosomes and enzyme activities were observed at 24 hours, 48 hours and 4 days to 90 days after irradiation. (Author)

Synaptonemal complex aberrations in the pseudoautosomal region of X, Y chromosomes in irradiated hamsters

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Allen, J.W.; Collins, B.W. [Environmental Protection Agency, Research Triangle Park, NC (United States); Poorman-Allen, P. [Wellcome Research Lab., Research Triangle Park, N.C. (United States); Sontag, M.R. [Duke Univ., Durham, NC (United States). Medical Center

1994-05-01

The effects of X-radiation, bleomycin and amsacrine (m-AMSA) on the meiotic chromosomes of male Armenian hamsters were determined by electron microscopic analysis of synaptonemal complex (SC) damage. Pachytene stage cells were analyzed 5 or 6 days following their treatment at putative preleptotene-leptotene stages of meiosis. Of the multiple types of SC aberrations observed to be significantly increased over control levels, lateral element breakage and synaptic anomalies were most prevalent. The focus of these studies was on the sex chromosomes which, in the Armenian hamster, reveal an unusally well-defined pseudoautosomal region. In the XY pair, radiation and chemical treatments caused certain forms of structural and synaptic anomalies which appeared to be preferentially localized to telomeric and/or crossover regions. The nature of these specific aberrations, involving breakage, bridge formation and asynapsis, is not well understood; however, their distributions are suggestive of possible relationships with sites and processes of crossing over. (author).

Frequency of primary amenorrhea due to chromosomal aberration

International Nuclear Information System (INIS)

Jabbar, S.

2004-01-01

Objective: To find out the frequency of primary amenorrhea due to chromosomal aberration and the different options available for management. Subjects and Methods: All patients with primary amenorrhea due to chromosomal aberrations were included in study. Patient's detailed history, general physical examination, presence or absence of secondary sexual characteristics, abdominal and pelvic examination finding were noted. Targeted investigations, including ultrasound, hormonal assay, buccal smear and karyotyping results were recorded. The management options were individually tailored with focus n psychological management. Results: Eighteen patients out of 30,000 patients were diagnosed as having primary amenorrhea. Six had primary amenorrhea due to chromosomal aberrations with the frequency of 0.02%. The age at presentation was 20 years and above in 50%. The most common cause was Turner's syndrome seen in 4 out of 6. The presenting symptoms were delay in onset of menstruation in 05 patients and primary infertility in 01 patient. Conclusion: Primary amenorrhea due to chromosomal aberration is an uncommon condition requiring an early and accurate diagnosis. Turner's syndrome is a relatively common cause of this condition. Management should be multi-disciplinary and individualized according to the patient's age and symptom at presentation. Psychological management is very important and counselling throughout treatment is recommended. (author)

Evaluation of chromosomal aberrations in radiologists and medical radiographers chronically exposed to ionising radiation

International Nuclear Information System (INIS)

Kasuba, V.; Rozgaj, R.; Jazbec, A.

2005-01-01

Chromosomal aberrations are fairly reliable indicators of damage induced by ionising radiation. This study included 180 radiologists and medical radiographers (technicians) and 90 controls who were not occupationally exposed to ionising radiation. All exposed subjects were routinely monitored with film badge, and none was exposed to a radiation dose exceeding the limit for occupational exposure recommended by the International Commission on Radiological Protection (ICRP). Two hundred metaphases for each person were scored. The frequencies of acentric fragments, dicentrics, ring chromosomes and chromosomal exchanges were determined and compared to those obtained in the control group. Chromosome aberrations were analysed using Poisson regression for profession, age, sex, smoking and years of exposure. Age, smoking, diagnostic exposure to X-rays and occupation were found to correlate with the occurrence of acentric fragments. The influence of exposure duration on the frequency of acentric fragments was greater in medical radiographers than in radiologists. Smoking and sex were found to correlate with the occurrence of dicentric chromosomes, which were more common in men than in women. As chromosome aberrations exceeded the expected level with respect to the absorbed dose, our findings confirm the importance of chromosome analysis as a part of regular medical check-up of subjects occupationally exposed to ionising radiation.(author)

Comparison of type and frequency of chromosome aberrations by conventional and G-staining methods in Hiroshima atomic bomb survivors

International Nuclear Information System (INIS)

Ohtaki, Kazuo; Shimba, Hachiro; Sofuni, Toshio; Awa, A.A.

1982-07-01

Somatic chromosomes derived from cultured lymphocytes of 23 atomic bomb survivors of Hiroshima were analyzed to determine the type and frequency of radiation-induced structural aberrations, using in sequence the ordinary staining method (O-method) and the trypsin G-banding method (G-method). Of 896 cells examined, 342 were found to contain induced aberrations, including 31 cells in which the precise identification of the type of aberrations was not possible even by the G-method. The number of chromosome aberrations observed was 376 in the 311 cells where aberrant precise identification was possible. The majority (288 or 76.6%) were intra- or inter-chromosomal symmetric exchanges due to a two-break event, while only 24 were found to be asymmetric exchanges (dicentrics, rings, and interstitial deletions). Further, there were 28 aberrations showing acentric fragments and terminal deletions, and the remaining 36 were complex intra- and inter-chromosomal exchanges involving three or more breaks which result in insertions and double translocations. A comparative karyotype analysis of the same metaphases examined by the sequential 0- And G-methods was carried out independently on 361 aberrations, mostly of the symmetric type. It was found that 78 (21.6%) of the 361 were detected only by the G-method; among these were 14 paracentric inversions, 48 reciprocal interchanges of chromosome segments with either equal length (11) or unequal length (37), 14 minor deletions and 2 complex rearrangements, all of which were nevertheless judged to fall within the normal range of variation by theO-method. In contrast, 25 aberrations detected in O-method chromosomes which were overcontracted or twisted, were shown to have normal banding patterns by the G-method. (author)

Chromosome aberrations in Norwegian reindeer following the Chernobyl accident

International Nuclear Information System (INIS)

Røed, K.H.; Jacobsen, M.

1995-01-01

Chromosome analyses were carried out on peripheral blood lymphocytes of semi-domestic reindeer in Norway which had been exposed to varying amounts of radiocesium emanating from the Chernobyl accident. The sampling was done in the period 1987-1990. The material included 192 reindeer, originating from four herds in central Norway, an area considerably affected by fallout from the Chernobyl accident, and from three herds in northern Norway which was unaffected by fallout from the accident. Significant heterogeneity in the distribution of chromosome aberrations between herds was observed. The pattern of chromosome aberration frequencies between herds was not related to the variation in radiocesium exposure from the Chernobyl accident. Other factors than the Chernobyl accident appear therefore to be of importance for the distribution of aberration frequencies found among present herds. Within the most contaminated area the reindeer born in 1986 showed significantly more chromosome aberrations than those born both before and after 1986. This could suggest that the Chernobyl accident fallout created an effect particularly among calves, during the immediate post-accident period in the most exposed areas

Study of radiation-induced chromosomal aberrations; Untersuchung strahleninduzierter Chromosomenaberrationen. Bestrahlung der Brustdruesenepithelzelllinie MCF-12A mit Roentgenstrahlung aus konventionellen Roentgenroehren und Bestimmung der Dosis-Effekt-Kurve. Studienarbeit

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Wolfring, E. [Technische Univ. Bergakademie Freiberg (Germany). Interdisziplinaeres Oekologisches Zentrum

2004-06-01

A method for determining chromosomal aberrations was established for the purpose of examining the relative biological effectiveness (RBE) of photon radiation with respect to mammary epithelium cells. Cells were exposed to 25 kV X-radiation and to 200 kV X-radiation for comparison and the resulting concentrations of chromosomal aberrations were compared. The RBE{sub M} value for radiation-induced fragmentation was found to be 4.2 {+-} 2.4, while the RBE{sub M} value for radiation-induced generation of dicentric chromosomes was found to be 0.5 {+-} 0.5. In addition to the evaluation of chromosomal aberrations the number of cell cycles undergone by the cells was monitored by means of BrDU staining. As expected, the proportion of cells which underwent more than one cell cycle following exposure to 5 Gy was very low in both cases, amounting to 1.9% (25 kV) and 3.2 (200 kV). Non-radiated cells yielded control values of 26.0% and 12.6%, suggesting variations in external conditions from day to day.

Chromosome painting analysis of radiation-induced aberrant cell clones in the mouse

International Nuclear Information System (INIS)

Spruill, M.D.; Nath, J.; Tucker, J.D.

1997-01-01

In a study of the persistence of radiation-induced translocations over the life span of the mouse, we observed a number of clonal cells in peripheral blood lymphocytes. The presence of clones caused the mean frequency of aberrations at various time points to be elevated which interfered with biodosimetry. For this reason, we have corrected our data for the presence of clones. Mice were given an acute dose of 0, 1, 2, 3 or 4 Gy 137 Cs at 8 weeks of age. Aberrations were measured by painting chromosomes 2 and 8 and cells were examined for clones at 3 months and every 3 months thereafter until 21 months. Clones were identified by comparing the color photographic slides of all abnormal cells from each animal. Determination of clonality was made on the basis of similar breakpoint locations or the presence of other identifying characteristics such as unusual aberrations. To correct the frequency of translocations for the presence of clones, each clone, regardless of how many cells it contained, was counted only once. This reflects the original aberration frequency since each clone originated as only one cell. Among mice exposed to 4 Gy, the mean frequencies of aberrant cell clones ranged from 3-29% of the total number of metaphase cells scored with the highest frequency being 1 year post exposure. 32-70% of reciprocal and 19-92% of non-reciprocal translocations were clonal. A dose response relationship for clones was evident until 21 months when the unexposed animals exhibited a mean frequency of aberrant cell clones >10% of the total number of cells scored. Almost 75% of reciprocal and 95% of non-reciprocal translocations in these unexposed control animals were of clonal origin. Correction for clonal expansion greatly reduced the means and their standard errors at most time points where clonal expansion was prevalent. The biodosimetry was much improved suggesting that correction is beneficial in long-term studies

Chromosome aberrations in monkey lymphocytes irradiated in vitro and in vivo

International Nuclear Information System (INIS)

Ziemba-Zak, B.

1976-01-01

The relationship between the X-ray dose and yield of dicentrics plus centric rings in monkey lymphocytes in vitro was studied. Frequency of these aberrations at different periods after in vivo exposure was also studied. No statistically significant differences were found between the yield of dicentrics plus centric rings obtained by in vitro and in vivo (up to 7 days) after irradiation. (author)

Combined cytokinesis-block micronucleus and chromosomal aberration assay for the evaluation of radiosensitizers at low radiation doses

International Nuclear Information System (INIS)

Oya, Natsuo; Shibamoto, Yuta; Shibata, Toru

1994-01-01

Several methods have been tried for evaluating the efficacy of hypoxic cell radiosensitizers at clinically relevant low radiation doses (1-4 Gy). The cytokinesis-block micronucleus assay is known to be useful for both the in vitro and in vivo evaluation of radiosensitizers, while the chromosomal aberration assay has been commonly used to assess the mutagenicity of various agents. In the present study, the chromosomal aberration assay and the cytokinesis-block micronucleus assay were performed simultaneously to assess the radiosensitizing effect of etanidazole and KU-2285 at low radiation doses. The correlation between the two assays was also evaluated. In vitro study: EMT-6 cells were irradiated at a dose of 1-3 Gy under hypoxic conditions with or without the drugs at 1 mM. In vivo-in vitro study: EMT-6 tumor-bearing BALB/c mice received 2-4 Gy of radiation with or without administration of the drugs at 200 mg/kg. Single-cell suspensions were then obtained in both studies and were used for the cytokinesis-block micronucleus assay and the chromosomal aberration assay. The micronucleus frequency in binucleate cells was evaluated in the former assay, and the frequency of chromosomal aberrations in metaphase cells was evaluated in the latter assay. In vitro study: the sensitizer enhancement ratios of etanidazole and KU-2285 were 1.73 and 2.21, respectively, in the micronucleus assay, and 1.41 and 1.79 in the chromosomal aberration assay. In vivo-in vitro study: the sensitizer enhancement ratios of etanidazole and KU-2285 were 1.18 and 1.31, respectively, in the micronucleus assay, and 1.16 and 1.42 in the chromosomal aberration assay. In both studies, a linear correlation was observed between the micronucleus frequency and the chromosomal aberration frequency. The background (i.e., the frequency at 0 Gy) of the latter assay was considerably lower than that of the former assay, especially in the in vivo study. 31 refs., 4 figs

A note on Poisson goodness-of-fit tests for ionizing radiation induced chromosomal aberration samples.

Science.gov (United States)

Higueras, Manuel; González, J E; Di Giorgio, Marina; Barquinero, J F

2018-05-18

To present Poisson exact goodness-of-fit tests as alternatives and complements to the asymptotic u-test, which is the most widely used in cytogenetic biodosimetry, to decide whether a sample of chromosomal aberrations in blood cells comes from an homogeneous or inhomogeneous exposure. Three Poisson exact goodness-of-fit test from the literature are introduced and implemented in the R environment. A Shiny R Studio application, named GOF Poisson, has been updated for the purpose of giving support to this work. The three exact tests and the u-test are applied in chromosomal aberration data from clinical and accidental radiation exposure patients. It is observed how the u-test is not an appropriate approximation in small samples with small yield of chromosomal aberrations. Tools are provided to compute the three exact tests, which is not as trivial as the implementation of the u-test. Poisson exact goodness-of-fit tests should be considered jointly to the u-test for detecting inhomogeneous exposures in the cytogenetic biodosimetry practice.

Influence of incorporated bromodeoxyuridine on the induction of chromosomal alterations by ionizing radiation and long-wave UV in CHO cells.

Science.gov (United States)

Zwanenburg, T S; van Zeeland, A A; Natarajan, A T

1985-01-01

Incorporation of BrdUrd into nuclear DNA sensitizes CHO cells (1) to the induction of chromosomal aberrations by X-rays and 0.5 MeV neutrons and (2) to induction of chromosomal aberrations and SCEs by lw-UV. We have attempted to establish a correlation between induced chromosomal alterations and induced single- or double-strand breaks in DNA. The data show that while DSBs correlate very well with X-ray-induced aberrations, no clear correlation could be established between lw-UV induced SSBs (including alkali-labile sites) and chromosomal alterations. In addition the effect of 3-aminobenzamide (3AB) on the induction of chromosomal aberrations and SCEs induced by lw-UV has been determined. It is shown that 3AB is without any effect when lw-UV-irradiated cells are posttreated with this inhibitor. The significance of these results is discussed.

Effect of met-enkephalin on chromosomal aberrations in the lymphocytes of the peripheral blood of patients with multiple sclerosis.

Science.gov (United States)

Rakanović-Todić, Maida; Burnazović-Ristić, Lejla; Ibrulj, Slavka; Mulbegović, Nedžad

2014-05-01

Endogenious opiod met-enkephalin throughout previous research manifested cytoprotective and anti-inflammatory effects. Previous research suggests that met-enkephalin has cytogenetic effects. Reducement in the frequency of structural chromosome aberrations as well as a suppressive effect on lymphocyte cell cycle is found. It also reduces apoptosis in the blood samples of the patients with immune-mediated diseases. Met-enkephalin exerts immunomodulatory properties and induces stabilization of the clinical condition in patients with multiple Sclerosis (MS). The goal of the present research was to evaluate met-enkephalin in vitro effects on the number and type of chromosome aberrations in the peripheral blood lymphocytes of patients with MS. Our research detected disappearance of ring chromosomes and chromosome fragmentations in the cultures of the peripheral blood lymphocytes treated with met-enkephalin (1.2 μg/mL). However, this research did not detect any significant effects of met-enkephalin on the reduction of structural chromosome aberrations and disappearance of dicentric chromosomes. Chromosomes with the greatest percent of inclusion in chromosome aberrations were noted as: chromosome 1, chromosome 2 and chromosome 9. Additionally, we confirmed chromosome 14 as the most frequently included in translocations. Furthermore, met-enkephalin effects on the increase of the numerical aberrations in both concentrations applied were detected. Those findings should be interpreted cautiously and more research in this field should be conducted.

Effect of met-enkephalin on chromosomal aberrations in the lymphocytes of the peripheral blood of patients with multiple sclerosis

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Maida Rakanović-Todić

2014-05-01

Full Text Available Endogenious opiod met-enkephalin throughout previous research manifested cytoprotective and anti-inflammatory effects. Previous research suggests that met-enkephalin has cytogenetic effects. Reducement in the frequency of structural chromosome aberrations as well as a suppressive effect on lymphocyte cell cycle is found. It also reduces apoptosis in the blood samples of the patients with immune-mediated diseases. Met-enkephalin exerts immunomodulatory properties and induces stabilization of the clinical condition in patients with multiple Sclerosis (MS. The goal of the present research was to evaluate met-enkephalin in vitro effects on the number and type of chromosome aberrations in the peripheral blood lymphocytes of patients with MS. Our research detected disappearance of ring chromosomes and chromosome fragmentations in the cultures of the peripheral blood lymphocytes treated with met-enkephalin (1.2 μg/mL. However, this research did not detect any significant effects of met-enkephalin on the reduction of structural chromosome aberrations and disappearance of dicentric chromosomes. Chromosomes with the greatest percent of inclusion in chromosome aberrations were noted as: chromosome 1, chromosome 2 and chromosome 9. Additionally, we confirmed chromosome 14 as the most frequently included in translocations. Furthermore, met-enkephalin effects on the increase of the numerical aberrations in both concentrations applied were detected. Those findings should be interpreted cautiously and more research in this field should be conducted. 

Some thoughts on the nature of chromosomal aberrations and their use as a quantitative end-point for radiobiological studies

International Nuclear Information System (INIS)

Savage, J.R.K.

1978-01-01

A vital condition when chromosomal aberrations are to be used as a quantitative end-point (e.g. for constructing a dose response curve) is that a specific dose must produce a specific yield of aberrations under a given set of experimental conditions. In practice, there are very few cell systems where this condition is met. The majority show significant variations in observed yield with time between irradiation and sampling, indicative of variable radiosensitivity within the cell population. The profile of this yield time curve is determined by the cell-cycle kinetics and therefore is itself subject to modification by radiation through mitotic delay and perturbation. Thus in such heterogeneous populations, each increment of dose not only induces more aberrations, but at the same time modifies the recovered yield per cell. This has an obvious bearing upon the interpretation of the shape of any dose-response curve obtained

Radiation-induced chromosomal aberrations in the lymphocytes of various species of mammals and the influence of coffeine during the G-2 phase

International Nuclear Information System (INIS)

Rosenthal, M.

1983-01-01

The cellular kinetics and the G0-radiation sensitivity of human, chimpanzee, swine and rabbit lymphocytes were investigated using the lymphocytes test system (Ham's F-10 Medium, PHA). Due to the integration of BrdU in the DNA (S-phase), the author was able to distinguish between first, second and third mitoses (M1, M2, M3) in accordance with the differential colouring of the metaphase chromosomes which took place according to the labelling pattern. When checking the G0-radiation sensitivity of the lymphocytes, the rates of chromosomal aberrations in the metaphases of the first and second mitoses were evaluated separately. The different radiation sensitivities are thought to be due to interspecies differences in the repair capacity of the lymphocytes. In the metaphases of second mitoses, the rate of dicentric chromosomes is approximately half of that in M1-metaphases. Ring chromosomes were nearly as frequent in M2-metaphases as in M1-metaphases. In the second experimental phase, the effects of coffein on the aberration rates after radiation exposure of the lymphocytes in the G2 phase was investigated. Achromatic lesions, open chromatide breaks, and translocations were evaluated. Aberration rates were found to increase with the radiation dose and to decrease with the cultivation time after radiation exposure. There was no marked effect of coffein on the aberration rates. The progress of the G2 phase was measured in terms of the rate of radioactively labelled metaphases, which increased with the cultivation time. This labelling index was lower in the exposed cultures than in the control cultures, suggesting a radiation-induced delay of the G2 phase. The labelling indexes of all cultures were enhanced after coffein treatment, suggesting a coffein-induced acceleration of the G2 phase. (orig./MG) [de

Transmission of clonal chromosomal abnormalities in human hematopoietic stem and progenitor cells surviving radiation exposure

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Kraft, Daniela, E-mail: d.kraft@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Ritter, Sylvia, E-mail: s.ritter@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Durante, Marco, E-mail: m.durante@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Institute for Condensed Matter Physics, Physics Department, Technical University Darmstadt, Hochschulstraße 6-8, 64289 Darmstadt (Germany); Seifried, Erhard, E-mail: e.seifried@blutspende.de [Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Fournier, Claudia, E-mail: c.fournier@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Tonn, Torsten, E-mail: t.tonn@blutspende.de [Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Technische Universität Dresden, Med. Fakultät Carl Gustav Carus, Institute for Transfusion Medicine Dresden, German Red Cross Blood Donation Service North-East, Blasewitzer Straße 68/70, 01307 Dresden (Germany)

2015-07-15

Highlights: • Radiation induced formation and transmission of chromosomal aberrations were assessed. • Cytogenetic analysis was performed in human CD34+ HSPC by mFISH. • We report transmission of stable aberrations in irradiated, clonally expanded HSPC. • Unstable aberrations in clonally expanded HSPC occur independently of irradiation. • Carbon ions and X-rays bear a similar risk for propagation of cytogenetic changes. - Abstract: In radiation-induced acute myeloid leukemia (rAML), clonal chromosomal abnormalities are often observed in bone marrow cells of patients, suggesting that their formation is crucial in the development of the disease. Since rAML is considered to originate from hematopoietic stem and progenitor cells (HSPC), we investigated the frequency and spectrum of radiation-induced chromosomal abnormalities in human CD34{sup +} cells. We then measured stable chromosomal abnormalities, a possible biomarker of leukemia risk, in clonally expanded cell populations which were grown for 14 days in a 3D-matrix (CFU-assay). We compared two radiation qualities used in radiotherapy, sparsely ionizing X-rays and densely ionizing carbon ions (29 and 60–85 keV/μm, doses between 0.5 and 4 Gy). Only a negligible number of de novo arising, unstable aberrations (≤0.05 aberrations/cell, 97% breaks) were measured in the descendants of irradiated HSPC. However, stable aberrations were detected in colonies formed by irradiated HSPC. All cells of the affected colonies exhibited one or more identical aberrations, indicating their clonal origin. The majority of the clonal rearrangements (92%) were simple exchanges such as translocations (77%) and pericentric inversions (15%), which are known to contribute to the development of rAML. Carbon ions were more efficient in inducing cell killing (maximum of ∼30–35% apoptotic cells for 2 Gy carbon ions compared to ∼25% for X-rays) and chromosomal aberrations in the first cell-cycle after exposure (∼70% and �

Stable and unstable chromosomal aberrations in workers at nuclear waste repository

International Nuclear Information System (INIS)

Hadjidekova, V.; Atanasova, P.; Iovchev, M.; Agova, S.

2004-01-01

A cytogenetic analysis of chromosomal aberrations was performed on 15 workers from final nuclear waste repository 'Novi Han'. The frequency of chromosomal aberrations were estimated in peripheral blood lymphocytes by conventional staining with Giemza and fluorescent in situ hybridization staining (FISH) using DNA specific probes. The results are compared with a control group from the administrative staff of the radioactive storage. All persons were interviewed by a special questionnaire list for professional, medical, and social status. The comparison of the results does not show increase of the frequency of unstable chromosomal aberrations detected by conventional staining. The frequency of stable chromosomal aberrations detected by FISH were significantly higher in workers group than in controls, although the statistical significance is low. The results show that FISH test is found to be more sensitive than conventional chromosomal analysis as a cytogenetic monitor test of the occupationally exposed subjects. (authors)

Role of DNA polymerase α in chromosomal aberration production by ionizing radiation

International Nuclear Information System (INIS)

Bender, M.A.

1983-01-01

Aphidicolin is a tetracyclic diterpinoid fungal antibiotic which inhibits DNA synthesis in eukaryotic cells by interfering specifically with DNA polymerase α, apparently by binding to and inactivating the DNA-polymerase α complex. We have shown that aphidicolin, like other inhibitors of DNA synthesis, both induces chromosomal aberrations in human peripheral lymphocytes, and, as a post-treatment, interacts synergistically with x rays to produce greatly enhanced aberration yields. The present experiments explore the effects of aphidicolin in human lymphocytes in the post-DNA-synthetic G 2 phase of the cell cycle. These experiments utilized labeling with tritiated thymidine to positively identify cells in the S phase at the time of treatment, and used serial colcemid collections and fixations to determine aberration yields over as much of the G 2 phase as feasible. Because DNA polymerase α is the only DNA synthetic or repair enzyme known to be affected by aphidicolin, we infer that this enzyme is directly involved in the repair of DNA lesions which can result in visible chromosomal aberrations. (DT)

Delayed formation of chromosome aberrations in mouse pachytebne spermatocytes treated with triethylenemelamine (TEM)

International Nuclear Information System (INIS)

Generoso, W.M.; Krishna, M.; Sotomayor, R.E.; Cacheiro, N.L.A.

1977-01-01

Induction of chromosome aberrations in pachytene spermatocytes of mice by 2 mg/kg TEM was compared with induction by 400 R x rays. These doses induced comparably high dominant lethal effects in pachytene spermatocytes of mice. Cytological analysis at diakinesis-metaphase I stage showed that whereas 76.4% of the cells treated with x rays at pachytene stage had aberrations, the frequencies observed in two TEM experiments were only 0.8 and 2.2%. On the other hand, 5% of the progeny from TEM-treated pachytene spermatocytes were found to be translocation heterozygotes. This is the first report on the recovery of heritable translocations from treated spermatocytes of mice. The aberration frequencies observed for TEM in diakinesis-metaphase I were much too low to account for all the lethal mutations and heritable translocations. Thus, the formation of the bulk of aberrations induced by TEM in pachytene spermatocytes was delayed--a marked contrast to the more immediate formation of x-ray-induced aberrations. It is postulated that the formation of the bulk of TEM-induced aberrations in pachytene spermatocytes and in certain postmeiotic stages occurs sometime during spermiogenesis, and not through the operation of postfertilization pronuclear DNA synthesis

Induction of Chromosomal Aberrations at Fluences of Less Than One HZE Particle per Cell Nucleus

Science.gov (United States)

Hada, Megumi; Chappell, Lori J.; Wang, Minli; George, Kerry A.; Cucinotta, Francis A.

2014-01-01

The assumption of a linear dose response used to describe the biological effects of high LET radiation is fundamental in radiation protection methodologies. We investigated the dose response for chromosomal aberrations for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) nuclei. Human fibroblast and lymphocyte cells where irradiated with several low doses of <0.1 Gy, and several higher doses of up to 1 Gy with O (77 keV/ (long-s)m), Si (99 keV/ (long-s)m), Fe (175 keV/ (long-s)m), Fe (195 keV/ (long-s)m) or Fe (240 keV/ (long-s)m) particles. Chromosomal aberrations at first mitosis were scored using fluorescence in situ hybridization (FISH) with chromosome specific paints for chromosomes 1, 2 and 4 and DAPI staining of background chromosomes. Non-linear regression models were used to evaluate possible linear and non-linear dose response models based on these data. Dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Best fits for the dose response data for human lymphocytes irradiated in blood tubes were a NTE model for O and a linear response model fit best for Si and Fe particles. Additional evidence for NTE were found in low dose experiments measuring gamma-H2AX foci, a marker of double strand breaks (DSB), and split-dose experiments with human fibroblasts. Our results suggest that simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. The current and prior experimental studies provide important evidence against the linear dose response assumption used in radiation protection for HZE particles and other high LET radiation at the relevant range of low doses.

Chromosome aberrations analysis of Serbia population from 1985 to 1995

International Nuclear Information System (INIS)

Jovicic, D.; Markovic, B.; Milacic, S.; Joksic, G.

1996-01-01

After the accident of NE Chernobyl in May 1986, Chernobyl's fallout with unhomogeneous dispersion of radioactive material in atmosphere caused the difference in contamination of the Serbia territory. The highest contamination was found to be in region Uzice, and the lowest in the region Nis. Two groups of population from these regions were undergone chromosome aberration analysis during 1987, 1988 and 1989. year. The results of our examination show increased frequency of structural chromosome aberrations/dicentrics, rings, peri centric inversions and acentric/ in the Uzice population, especially in the 1987. year. In 1985 and 1995 year have not been found chromosome aberrations. 2 refs.; 1 figs.; 2 tabs

mBAND analysis for high- and low-LET radiation-induced chromosome aberrations: A review

Energy Technology Data Exchange (ETDEWEB)

Hada, Megumi, E-mail: megumi.hada-1@nasa.gov [NASA Johnson Space Center, Houston, TX 77058 (United States); Universities Space Research Association, Houston, TX 77058 (United States); Wu Honglu; Cucinotta, Francis A. [NASA Johnson Space Center, Houston, TX 77058 (United States)

2011-06-03

During long-term space travel or cancer therapy, humans are exposed to high linear energy transfer (LET) energetic heavy ions. High-LET radiation is much more effective than low-LET radiation in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, and cytogenetic damage can be utilized as a biomarker for radiation insults. Epidemiological data, mainly from survivors of the atomic bomb detonations in Japan, have enabled risk estimation from low-LET radiation exposures. The identification of a cytogenetic signature that distinguishes high- from low-LET exposure remains a long-term goal in radiobiology. Recently developed fluorescence in situ hybridization (FISH)-painting methodologies have revealed unique endpoints related to radiation quality. Heavy-ions induce a high fraction of complex-type exchanges, and possibly unique chromosome rearrangements. This review will concentrate on recent data obtained with multicolor banding in situ hybridization (mBAND) methods in mammalian cells exposed to low- and high-LET radiations. Chromosome analysis with mBAND technique allows detection of both inter- and intrachromosomal exchanges, and also distribution of the breakpoints of aberrations.

Effects of turmeric and its active principle, curcumin, on bleomycin-induced chromosome aberrations in Chinese hamster ovary cells

OpenAIRE

Araújo, Maria Cristina P.; Dias, Francisca da Luz; Kronka, Sergio N. [UNESP; Takahashi, Catarina S.

1999-01-01

Naturally occurring antioxidants have been extensively studied for their capacity to protect organisms and cells from oxidative damage. Many plant constituents including turmeric and curcumin appear to be potent antimutagens and antioxidants. The effects of turmeric and curcumin on chromosomal aberration frequencies induced by the radiomimetic agent bleomycin (BLM) were investigated in Chinese hamster ovary (CHO) cells. Three concentrations of each drug, turmeric (100, 250 and 500 mg/ml) and ...

Explanation of test and assessment of chromosomal aberrations on occupational health examinations for radiation workers

International Nuclear Information System (INIS)

Lu Yumin; Fu Baohua; Han Lin; Wang Xi'ai; Zhao Fengling

2012-01-01

Test and Assessment of Chromosomal Aberrations on Occupational Health Examinations for Radiation Workers was formulated for standardizing analysis and outcome assessment of chromosomal aberrations on occupational health examinations for radiation workers. In order to provide experimental and theoretical basis for implementation and extension of this standard, this paper interpreted the standard comprehensively, including some existed problems that methods on detection and outcome assessment of chromosomal aberrations is not unified in different laboratories in China, and related criteria,laws and regulations at home and abroad are not fit for the detection of chromosomal aberrations for radiation workers very well; some introduction on methods of chromosomal slide preparation, discriminant analysis and outcome assessment of chromosomal aberration; and some influencing factors in the quality of chromosomal aberration detection. (authors)

Chromosome aberrations of bone marrow cells in heavily exposed atomic bomb survivors

International Nuclear Information System (INIS)

Tanaka, Kimio; Kamada, Nanao; Kuramoto, Atsushi; Ohkita, Takeshi

1986-01-01

Seven hundred and ten bone marrow cells from 13 A-bomb survivors, who were heavily exposed to atomic radiation, were examined using chromosome banding method. An average frequency of chromosome aberrations was 17 %. The most common structural abnormality was translocation (47 %), followed by complex aberrations involving three or more chromosomes (32 %). These abnormalities were frequently seen in A-bomb survivors exposed to estimated doses of 3.5 - 4.0 Gy. Eighty two percent of the structural aberrations were stable. Diploid cells were seen in 0.4 % and tetraploid cells were seen in 0.7 %. The frequency of breakpoint sites was high in chromosomes 1 and 17; while it was low in chromosomes 3, 6, 9, and 11. Abnormal clones were seen in one of the 13 survivors. Chromosome aberrations common to the bone marrow cells and peripheral lymphocytes were not seen in the same individual. (Namekawa, K.)

Computer-assisted detection of chromosomal aberrations for the purpose of establishing a biological dosimeter

International Nuclear Information System (INIS)

Ueberreiter, B.

1982-01-01

Using a special high-resolution microscopy apparatus, digital light microscope images of human chromosomes were generated, and specific image processing algorithms were developed. The pattern recognition process for computer-assisted detection of specific, radiation-induced chromosomal aberrations comprises three steps: First, the orientation of the segmented objects is defined and corrected. For date reduction purposes, the individual chromosomes are reduced to a few basic types containing typical information. After a linear transformation step, the characteristic parameters thus derived form a parameter vector for statistical classification. The method was well suited for distinguishing normal chromosomes from chromosomal aberrations. 94% of the objects were identified correctly. To achieve even higher accuracy, quality standards were set by which suspectedly misclassified objects can be re-investigated in dialog by the human observer. Implementation of the program system for parameter extraction on a fast polyprocessor system opens up a realistic chance of reducing the computing time for dose estimates to about one hour. (orig./MG) [de

Body-weight and chromosome aberrations induced by X-rays in somatic cells of Drosophila melanogaster

International Nuclear Information System (INIS)

Marco, A. de; Belloni, M.P.

1976-01-01

Body-weight has been shown to influence the final expression of genetic damage by X-rays in Drosophila melanogaster. If larvae of Drosophila were raised up to the third instar in media containing different amounts of the same nutrient and in different conditions of crowding a positive correlation was observed between body-weight and frequency of chromosome aberrations induced by a given dose of X-rays in the somatic cells of their nerve ganglia. This effect, present in both sexes, is most plausibly attributed to a different capacity of big and small larvae for repairing radiation damage. (orig.) [de

The study of chromosome aberration yield in human lymphocytes as an indicator of radiation dose. 1. Techniques

International Nuclear Information System (INIS)

Purrott, R.J.; Lloyd, D.C.

1972-08-01

Estimates of exposure to ionizing radiation can be obtained by determining the yield of chromosome aberrations in cultured human lymphocytes. Chromosomes can only be conveniently examined during cell division. The lymphocytes, which do not normally divide whilst circulating, are stimulated to divide during a 48-hour culture period. Two types of culture technique are described, one of which employs a lymphocyte-enriched inoculum and the other which uses whole blood. After culture the cells are harvested, dispensed onto slides and prepared for microscopic examination. An account is also given of the analysis of various types of radiation-induced chromosome aberrations and of the construction of calibration curves for certain types and rates of radiation which are used to interpret the aberration yields in terms of dose. (author)

Chromosomal aberrations and micronuclei frequencies in Bulgarian control population

International Nuclear Information System (INIS)

Popova, I.; Hadjidekova, V.; Hristova, R.; Atanasova, P.

2004-01-01

The aim of this investigation is to represent the frequency of spontaneous chromosomal damages in peripheral blood lymphocytes of Bulgarian control population. Material and methods: The investigated group includes persons belonging to both sexes and different ages. Each of them is interviewed of their social and health status. Sixteen persons are examined using the chromosomal aberrations analysis and forty-five with micronucleus test. The frequency of chromosomal aberrations varied between 0 - 2.4 % and the mean value is 1.00 %. The frequency of cells with micronuclei varied between 4.5 - 24.5 % and the mean value 12,9 %. Further work on the investigation of spontaneous frequency of chromosomal damages is in progress. (authors)

Chromosomal aberrations in humans induced by urban air pollution: influence of DNA repair and polymorphisms of glutathione S-transferase M1 and N-acetyltransferase 2

DEFF Research Database (Denmark)

Knudsen, Lisbeth E.; Norppa, H; Gamborg, M O

1999-01-01

We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes as a biomar......We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes...... that long-term exposure to urban air pollution (with traffic as the main contributor) induces chromosome damage in human somatic cells. Low DNA repair capacity and GSTM1 and NAT2 variants associated with reduced detoxification ability increase susceptibility to such damage. The effect of the GSTM1 genotype......, which was observed only in the bus drivers, appears to be associated with air pollution, whereas the NAT2 genotype effect, which affected all subjects, may influence the individual response to some other common exposure or the baseline level of chromosomal aberrations....

Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with {sup 60}Co; Analise da frequencia de alteracoes cromossomicas instaveis em linfocitos humanos irradiados com {sup 60}Co

Energy Technology Data Exchange (ETDEWEB)

Mendonca, Julyanne C.G.; Mendes, Mariana E.; Lima, Fabiana F., E-mail: july_cgm@hotmail.com, E-mail: mendes_sb@hotmail.com [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Santos, Neide, E-mail: santos_neide@yahoo.com.br [Universidade Federal de Pernambuco (CCB/UFPE), Recife, PE (Brazil). Departamento de Genetica

2013-07-01

The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a {sup 60}Co source at two different doses. Samples were obtained from a healthy donor and exposed to {sup 60}Co source (Gammacel 220 ) located in the Department of Nuclear Energy of Pernambuco Federal University (DEN/UFPe/Brazil) with a rate of air Kerma to 3,277 Gy/h. Exposures resulted in absorbed dose 0.51 Gy and 0.77 Gy. Mitotic metaphases were obtained by culturing lymphocytes for chromosome analysis and the slides were stained with 5% Giemsa. Among the unstable chromosomal aberrations the dicentric chromosomes, ring chromosomes and acentric fragments were analyzed. To calculate the significance level the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. To calculate the significance level of the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. The results showed that there was significant difference of the frequencies of dicentric chromosomes (from 0.18 to 0.51 to 0.37 Gy to 0.77 Gy), however there was no statistically significant difference between the frequencies of acentric fragments ( 0.054 to 0, 51 Gy to 0.063 to 0.77 Gy) and ring chromosomes (0.001 to 0.51 Gy to 0.003 to 0.77 Gy). The low number of rings is found justified, considering that in irradiated human lymphocytes, its appearance is rare relative to dicentrics. The results confirm that dicentrics are the most reliable biomarkers in estimating dose after exposure to gamma radiation. These two points will make the calibration curve dose-response being built for Biological Dosimetry Laboratory of CRCN-NE/CNEN.

Cells bearing chromosome aberrations lacking one telomere are selectively blocked at the G2/M checkpoint

Energy Technology Data Exchange (ETDEWEB)

Rodriguez, Pilar [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Barquinero, Joan Francesc [Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Duran, Assumpta [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Caballin, Maria Rosa [Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Ribas, Montserrat [Servei de Radiofisica i Radioproteccio de l' Hospital de la Santa Creu i Sant Pau, 08025 Barcelona (Spain); Barrios, Leonardo, E-mail: Lleonard.Barrios@uab.cat [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

2009-11-02

Cell cycle checkpoints are part of the cellular mechanisms to maintain genomic integrity. After ionizing radiation exposure, the cells can show delay or arrest in their progression through the cell cycle, as well as an activation of the DNA repair machinery in order to reduce the damage. The G2/M checkpoint prevents G2 cells entering mitosis until the DNA damage has been reduced. The present study evaluates which G0 radiation-induced chromosome aberrations are negatively selected in the G2/M checkpoint. For this purpose, peripheral blood samples were irradiated at 1 and 3 Gy of {gamma}-rays, and lymphocytes were cultured for 48 h. Calyculin-A and Colcemid were used to analyze, in the same slide, cells in G2 and M. Chromosome spreads were consecutively analyzed by solid stain, pancentromeric and pantelomeric FISH and mFISH. The results show that the frequency of incomplete chromosome elements, those lacking a telomeric signal at one end, decreases abruptly from G2 to M. This indicates that cells with incomplete chromosome elements can progress from G0 to G2, but at the G2/M checkpoint suffer a strong negative selection.

Cells bearing chromosome aberrations lacking one telomere are selectively blocked at the G2/M checkpoint

International Nuclear Information System (INIS)

Rodriguez, Pilar; Barquinero, Joan Francesc; Duran, Assumpta; Caballin, Maria Rosa; Ribas, Montserrat; Barrios, Leonardo

2009-01-01

Cell cycle checkpoints are part of the cellular mechanisms to maintain genomic integrity. After ionizing radiation exposure, the cells can show delay or arrest in their progression through the cell cycle, as well as an activation of the DNA repair machinery in order to reduce the damage. The G2/M checkpoint prevents G2 cells entering mitosis until the DNA damage has been reduced. The present study evaluates which G0 radiation-induced chromosome aberrations are negatively selected in the G2/M checkpoint. For this purpose, peripheral blood samples were irradiated at 1 and 3 Gy of γ-rays, and lymphocytes were cultured for 48 h. Calyculin-A and Colcemid were used to analyze, in the same slide, cells in G2 and M. Chromosome spreads were consecutively analyzed by solid stain, pancentromeric and pantelomeric FISH and mFISH. The results show that the frequency of incomplete chromosome elements, those lacking a telomeric signal at one end, decreases abruptly from G2 to M. This indicates that cells with incomplete chromosome elements can progress from G0 to G2, but at the G2/M checkpoint suffer a strong negative selection.

Poisson goodness-of-fit tests for radiation-induced chromosome aberrations

International Nuclear Information System (INIS)

Merkle, W.

1981-01-01

Asymptotic and exact Poisson goodness-to-fit tests have been reviewed with regard to their applicability in analysing distributional properties of data on chromosome aberrations. It has been demonstrated that for typical cytogenetic samples, i.e. when the average number of aberrations per cell is smaller than one, results of asymptotic tests, especially of the most commonly used u-test, differ greatly from results of corresponding exact tests. While the u-statistic can serve as a qualitative index to indicate a tendency towards under- or over-dispersion, exact tests should be used if the assumption of a Poisson distribution is crucial, e.g. in investigating induction mechanisms. If the main interest is to detect a difference between the mean and the variance of a sample it is furthermore important to realize that a much larger sample size is required to detect underdispersion than it is to detect overdispersion. (author)

Use of FISH-translocations analyses for retrospective biological dosimetry: How stable are stable chromosome aberrations?

International Nuclear Information System (INIS)

Darroudi, F.

2000-01-01

Chromosome aberrations, in particular dicentrics, in peripheral blood lymphocytes are used to estimate the absorbed dose immediately following a radiation accident. However, difficulties for dose estimation arise with old exposures, due to a decline of cells containing unstable dicentric aberrations. The fluorescence in situ hybridisation (FISH) technique employing chromosome specific DNA libraries to 'paint' individual human chromosomes has opened new perspectives for rapid and reliable detection of stable chromosome aberrations such as translocations. The inherent stability of translocations over cell generations has enabled them to be used as a biodosemeter. However, due to the limited life of circulating T-lymphocytes, a level of uncertainty exists on the long-term persistence of stable translocations. The objectives of the present work are to present the current state of knowledge on the stability of translocations detected by FISH. The following aspects have been considered; (1) experience so far of retrospective biological dosimetry in humans following accidental and occupational over-exposure, (2) animal studies using mice and monkeys, (3) the influence of subsequent cell divisions on the yield and persistence of translocations following in vitro irradiation of human lymphocytes, and (4) the needs for further work to standardise and validate the use of FISH as a biological dosemeter, and to investigate the influence of various parameters such as radiation quality, dose rate and the discrimination of sub-types of translocations on persistence. (author)

Chromosomal aberrations in peripheral lymphocytes from A-bomb survivors who entered the city early after A-bombing

International Nuclear Information System (INIS)

Koguma, Nobuo; Kamada, Nanao

1992-01-01

It has been thought that A-bomb survivors who entered the city early after A-bombing were exposed to residual A-bomb radiation both externally and internally (through inhalation, food, drink or skin). This paper summarizes the data on estimated radiation doses in A-bomb survivors who entered Hiroshima within 3 days after A-bombing based on the chromosome staining analysis of lymphocytes of peripheral blood taken from A-bomb survivors. The subjects were 40 A-bomb survivors; according to a stay period and a history of medical irradiation, they were divided into four: group A with a long stay, group B with a long stay + medical irradiation, group C with a short stay, and group D with a short stay + medical irradiation. A mean estimated radiation dose was 4.8 rad (one rad or less to 13.5 rad) in group A, 13.9 rad (one rad or less to 71.2 rad) in group B, one rad or less in group C, and 1.9 rad (one rad or less to 21.2 rad) in group D. The highest rate of chromosomal aberrations was 3.1% in group B, followed by 2.1% in group A, 0.83% in group D, and 0.73% in group C. The frequency of chromosomal aberrations was coincident with the duration of stay in the city. Furthermore, medical irradiation seemed to have contributed to the additional effects of A-bomb radiation. (N.K.)

New trends and techniques in chromosome aberration analysis

International Nuclear Information System (INIS)

Bender, M.A.

1978-01-01

The following topics are discussed: automation of chromosome analysis; storage of fixed cells from cultures of lymphocytes obtained routinely during periodic employee medical examinations; analysis of banded chromosomes; identification of first division metaphases; sister chromatid exchange; and patterns of aberration induction

[Frequency of chromosome aberrations in residents of the Semipalatinsk Oblast].

Science.gov (United States)

Gubitskaia, E G; Akhmatullina, N B; Vsevolodov, E B; Bishnevskaia, S S; Sharipov, I K; Cherednichenko, O G

1999-06-01

Cytogenetic analysis of the population of the Beskaragai district of the Semipalatinsk oblast adjacent to the territory of the nuclear test site was conducted by means of an ecological genetic questionnaire and cytogenetic examination of metaphase chromosomes. An increase in the total mutation level in the region was observed. The frequency of chromosome aberrations among the population of the Beskaragai district (3.2%) was statistically significantly (about 1.5 times) higher than the background levels in the clear regions (from 1 to 2%). Furthermore, the frequency of aberrations in adolescents was comparable with that in the adults. The spectrum of chromosome aberrations pointed to a significant contribution of radiation component to the mutagenesis.

Impact of types of lymphocyte chromosomal aberrations on human cancer risk

DEFF Research Database (Denmark)

Hagmar, Lars; Strömberg, Ulf; Bonassi, Stefano

2004-01-01

The frequency of cells with structural chromosomal aberrations (CAs) in peripheral blood lymphocytes is the first genotoxicity biomarker that has shown an association with cancer risk. CAs are usually divided into chromosome-type (CSAs) and chromatid-type aberrations (CTAs), with different mechan...

Noninvolvement of the X chromosome in radiation-induced chromosome translocations in the human lymphoblastoid cell line TK6

International Nuclear Information System (INIS)

Jordan, R.; Schwartz, J.L.

1994-01-01

Fluorescence in situ hybridization procedures were used to examine the influence of chromosome locus on the frequency and type of chromosome aberrations induced by 60 Co γ rays in the human lymphoblastoid cell line TK6. Aberrations involving the X chromosome were compared to those involving the similarly sized autosome chromosome 7. When corrected for DNA content, acentric fragments were induced with equal frequency in the X and 7 chromosomes. Dose-dependent increases in chromosomal interchanges involving chromosome 7 were noted, and the frequencies of balanced translocations and dicentrics produced were approximately equal. Chromosome interchanges involving the X chromosome were rare and showed no apparent dose dependence. Thus, while chromosomes 7 and X are equally sensitive to the induction of chromosome breaks, the X chromosome is much less likely to interact with autosomes than chromosome 7. The noninvolvement of the X chromosome in translocations with autosomes may reflect a more peripheral and separate location for the X chromosome in the mammalian nucleus. 20 refs., 2 figs., 1 tab

The chromosomal radiosensitivity of lymphocytes from the chimpanzee (Pan troglodytes)

International Nuclear Information System (INIS)

Leonard, A.; Decat, G.; Leonard, E.D.; Mortelmans, J.

1977-01-01

The yield of chromosomal aberrations induced by exposure to X-irradiation in vitro was studied in the lymphocytes of the chimpanzee (Pan troglodytes), a hominoid ape phylogenically and chromosomally closely related to man. In agreement with the similarity of the chromosome characteristics, no significant difference was observed between man and chimpanzee with respect to the incidence of dicentrics and fragments. It is obvious that the nuclear area, which apparently constitutes the most evident difference between the nuclei of man and chimpanzee lymphocytes, did not play an important role in the yields of aberrations

Establishment and verification of dose-response curve of chromosomal aberrations after exposure to very high dose γ-ray

International Nuclear Information System (INIS)

Chen Ying; Luo Yisheng; Cao Zhenshan; Liu Xiulin

2006-01-01

To estimate accurately biological dose of the victims exposed to high dose, the dose-response curves of chromosome aberration induced by 6-22 Gy 60 Co γ-ray were established. Human peripheral blood in vitro was irradiated, then lymphocytes were concentrated, cultured 52h, 68h and 72h and harvested. The frequencies of dicentrics (multi-centrics) and rings were counted and compared between different culture times. The dose-response curves and equations were established, as well as verified with high dose exposure accidents. The experiment showed that the culture time should be prolonged properly after high dose exposure, and no significant differences were observed between 52-72h culture. The dose-response curve of 6-22 Gy fitted to linear-square model Y=-2.269 + 0.776D - 7.868 x 10 -3 D 2 and is reliable through verification of the accident dose estimations. In this study, the dose-response curve and equation of chromosome dic + r after 6-22 Gy high dose irradiation were established firstly, and exact dose estimation can be achieved according to it. (authors)

Chromosomal aberrations induced by caffeine, 3H-thymidine and by X-rays in two L5178Y sublines of different radiosensitivity. Part 1. Chromosomal aberrations in cells treated with 2mM caffeine and tritiated thymidine

International Nuclear Information System (INIS)

Bocian, E.; Bouzyk, E.; Rosiek, O.; Ziemba-Zoltowska, B.

1982-01-01

Chromosomal aberrations were studied in two sublines of L5178Y cells with different sensitivity to X-rays. Cells were treated with 2 mM caffeine for 12 h. Then they were examined at various time intervals from 5 to 24 h. Caffeine caused over three times more aberrations, mainly chromatid breaks and gaps, in radiation-sensitive L5178Y-S than in radiation-resistant L5178Y-R cells. The maximum frequency of chromatid breaks in both sublines was found at 8 h and that of chromatid exchanges and isochromatid breaks at 12 h after treatment. A dramatic decrease of the frequency of all types of aberrations at 24 h was observed. In the pulse labelled experiments caffeine enhanced the frequency of aberrations that were induced by 3 H-thymidine at a concentration of 1 μCi/ml. This effect of caffeine was greater in L5178Y-R than in L5178Y-S cells. (author)

[Mechanistic modelling allows to assess pathways of DNA lesion interactions underlying chromosome aberration formation].

Science.gov (United States)

Eĭdel'man, Iu A; Slanina, S V; Sal'nikov, I V; Andreev, S G

2012-12-01

The knowledge of radiation-induced chromosomal aberration (CA) mechanisms is required in many fields of radiation genetics, radiation biology, biodosimetry, etc. However, these mechanisms are yet to be quantitatively characterised. One of the reasons is that the relationships between primary lesions of DNA/chromatin/chromosomes and dose-response curves for CA are unknown because the pathways of lesion interactions in an interphase nucleus are currently inaccessible for direct experimental observation. This article aims for the comparative analysis of two principally different scenarios of formation of simple and complex interchromosomal exchange aberrations: by lesion interactions at chromosome territories' surface vs. in the whole space of the nucleus. The analysis was based on quantitative mechanistic modelling of different levels of structures and processes involved in CA formation: chromosome structure in an interphase nucleus, induction, repair and interactions of DNA lesions. It was shown that the restricted diffusion of chromosomal loci, predicted by computational modelling of chromosome organization, results in lesion interactions in the whole space of the nucleus being impossible. At the same time, predicted features of subchromosomal dynamics agrees well with in vivo observations and does not contradict the mechanism of CA formation at the surface of chromosome territories. On the other hand, the "surface mechanism" of CA formation, despite having certain qualities, proved to be insufficient to explain high frequency of complex exchange aberrations observed by mFISH technique. The alternative mechanism, CA formation on nuclear centres is expected to be sufficient to explain frequent complex exchanges.

Detection of chromosomal aberrations by fluorescence in situ hybridization in the first three postirradiation divisions of human lymphocytes

International Nuclear Information System (INIS)

Boei, J.J.W.A.; Vermeulen, S.; Natarajan, A.T.

1996-01-01

Chromosomal aberrations in human lymphocytes were analyzed by fluorescence in situ hybridization (FISH) in the first 3 postirradiation (0 and 2 Gy) divisions. Cells were grown in the presence of BrdU, collected at different sampling times (47, 70 and 91 h) and analyzed using an alphoid centromeric probe and PCR amplified DNA libraries for chromosomes 2 and 8. Following differential staining of sister chromatids, the analyzed cells were identified to be either in the first, second or third mitosis after irradiation. The frequencies of both dicentrics and fragments showed a reduction of about 50% after each cell generation, whereas translocations were more persistent. Cells within the same postirradiation division showed higher aberration frequencies when derived from later sampling times, indicating a delay in progression of aberrant cells. As a result, the frequencies for dicentrics and fragments remained rather constant at different sampling times if the cell cycle parameter was not taken into account. Thus, the average generation time of the lymphocytes had a clear effect on the obtained aberration frequencies. The described method allows the study of the persistence of chromosome damage using the FISH technique during 3 subsequent cell divisions in vitro

Chromosome aberrations as a biological dosimeter in Thorotrast patients: dosimetric problems

International Nuclear Information System (INIS)

Kemmer, W.; Steinstraesser, A.; Muth, H.

1979-01-01

The results of chromosome aberration analyses in 68 Thorotrast patients are discussed. In all patients dicentric chromosome aberrations were found but the chromosome aberration rate neither corresponds with the calculated whole body activity or the estimated absorbed dose in the organs of the RHS nor with the radium-224-equivalent value calculated from the radon-220 activity measured in the expired air. From x-ray examinations and histologic studies of lymph nodes the conclusion is drawn that the microdose absorbed from one lymphocyte is not in relation to the mean absorbed RHS dose, calculated from biophysical measurements

Persistent genetic instability induced by synergistic interaction between x-irradiation and 6-thioguanine

International Nuclear Information System (INIS)

Grosovsky, A.J.; Nelson, S.L.; Smith, L.E.

1995-01-01

Clonal karyotypic analysis was performed using G-banding on four groups of clones derived from TK6 human lymphoblasts: 25 HPRT - total gene deletion mutants induced by exposure to 2 Gy of x-rays; 8 spontaneous HPRT - total gene deletion mutants; 25 clones irradiated with 2 Gy, not selected with 6-thioguanine. Ten to twenty metaphases were examined for each clone. Extensive karyotypic heterogeneity was observed among x-ray induced HPRT - mutants involving translocations, deletions, duplications and aneuploidy; recovery of chromosomal aberrations and karyotypic heterogeneity was greater than the additive effects of clones treated with x-irradiation or 6-thioguanine alone. This synergistic interaction between x-irradiation and 6-thioguanine was observed despite a 7 day phenotypic expression interval between exposure to the two agents. Thus, x-irradiated TK6 cells appear to be persistently hypersensitive to the induction of genetic instability. Several mutants appeared to exhibit evidence of clonal evolution since aberrant chromosomes observed in one metaphase, were found to be further modified in other metaphases. In order to determine if genetic instability, identified by clonal karyotypic heterogeneity, affected specific locus mutation rates, we utilized the heterozygous thymidine kinase (tk) locus as a genetic marker. Four x-ray induced HPRT - mutants with extensive karyotypic heterogeneity, exhibited mutation rates at tk ranging from 5 to 8 fold higher than the parental TK6 cells. Further analysis, using fractionated low dose radiation exposure, is currently in progress

Ionizing radiation and frequency of chromosomal aberrations in exposed personnel

International Nuclear Information System (INIS)

Spasojevic-Tisma, Vera; Pavlovic, Snezana

2008-01-01

Full text: Frequencies of chromosomal aberrations in lymphocytes of peripheral blood were investigated among the observed groups of subjects who were exposed to low radiation doses (external exposure) in comparison with the control group. The first group of subjects is involved in the production of radioisotope technetium, whose accumulated work exposure time ranges between 3 and 30 years. The second group works on inspection of the medical X-ray equipment, whose accumulated work exposure time is between 2 and 34 years. The third group worked on decontamination of the terrain from depleted uranium radioactive ammunition. These workers were involved in mechanical removal of the surface soil layer to a depth of 50 cm. They were selected out of a group of professionals otherwise exposed to radiation from confined sources in their daily work. The accumulated work exposure of this group ranged from 2 to 34 years. The control group consisted of individuals not working in the ionizing radiation zone. The average yearly absorbed dose measured by TL dosimeters for all three observed groups did not exceed 2 mSv. The chromosomal aberrations were analyzed by a modified Moorhead method. The objective of the study was to establish the existence of differences in the frequencies of chromosomal aberrations change with respect to the source type, i.e. type of radioactive emission. Comparisons of the chromosomal changes in the observed groups revealed that the group working on technetium production had an increase in the frequency of chromosomal aberrations with respect to control. The aberrations found were of the acentric fragment and chromosomal break types. A comparison of the exposed groups between each other, no statistically significant differences in the numbers of chromosomal aberrations were found. Soil decontamination from depleted uranium did not contribute to the relative radiation risk, since it lasted only a few months, and was done by the professionals fully clothed

Dose assessment by quantification of chromosome aberrations and micronuclei in peripheral blood lymphocytes from patients exposed to gamma radiation

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Silva-Barbosa, Isvania; Pereira-MagnataI, Simey; Amaral, Ademir [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia - GERAR; Sotero, Graca [Fundacao de Hematologia e Hemoterapia, Recife, PE (Brazil); Melo, Homero Cavalcanti [Hospital do Cancer, Recife, PE (Brazil). Centro de Radioterapia de Pernambuco]. E-mail: isvania@uol.com.br

2005-07-15

Scoring of unstable chromosome aberrations (dicentrics, rings and fragments) and micronuclei in circulating lymphocytes are the most extensively studied biological means for estimating individual exposure to ionizing radiation (IR), which can be used as complementary methods to physical dosimetry or when the latter cannot be performed. In this work, the quantification of the frequencies of chromosome aberrations and micronuclei were carried out based on cytogenetic analyses of peripheral blood samples from 5 patients with cervical uterine cancer following radiotherapy in order to evaluate the absorbed dose as a result of partial-body exposure to 60Co source. Blood samples were collected from each patient in three phases of the treatment: before irradiation, 24 h after receiving 0.08 Gy and 1.8 Gy, respectively. The results presented in this report emphasize biological dosimetry, employing the quantification of chromosome aberrations and micronuclei in lymphocytes from peripheral blood, as an important methodology of dose assessment for either whole or partial-body exposure to IR.

Cytosine arabinoside enhancement of gamma irradiation induced mutations in human T-lymphocytes

International Nuclear Information System (INIS)

O'Neill, J.P.; Sullivan, L.M.; Hunter, T.C.; Nicklas, J.A.

1991-01-01

The frequency of 6-thioguanine resistant (TGr) mutants induced in human G0 phase T-lymphocytes by 200 cGy of gamma irradiation is greatly enhanced by incubation with cytosine arabinoside (ara-C) after irradiation. The mutant frequency increased with increasing incubation time in ara-C for up to 2 hr. This mutation induction required a phenotypic expression time of 5-8 days mass culture growth, similar to that found with mutants induced by 300 cGy of irradiation alone. Southern blot analysis of 40 isolated mutant clones revealed 8 independent mutations by T-cell receptor (TCR) gene rearrangement patterns. Four of these eight showed hprt gene structural alterations (0.50). An alternative method to allow phenotypic expression was developed to minimize the isolation of hprt/TCR sibling mutants. The use of in situ expression in the microtiter dish wells resulted in the isolation of 17 independent mutations in 19 mutant clones. Ten of these 17 mutations showed hprt structural alterations (0.59). The high fraction of mutations involving structural alterations detected by Southern blot analysis is consistent with the known induction of chromosome aberrations by irradiation plus ara-C treatment. We propose that both the increase in Mf and the increase in the incidence of hprt gene structural alterations are due to the accumulation of strand breaks in repairing regions of DNA under these conditions of ara-C induced inhibition of repair. We further propose that upon release of the ara-C inhibition, these repairing regions can interact to yield both gene mutations and chromosome aberrations

Chromosomal Aberrations in Monozygotic and Dizygotic Twins Versus Singletons in Denmark During 1968-2009

DEFF Research Database (Denmark)

Kristensen, Lone Krøldrup; Larsen, Lisbeth A; Fagerberg, Christina

2017-01-01

BACKGROUND: Hall (Embryologic development and monozygotic twinning. Acta Geneticae Medicae et Gemellologiae, Vol. 45, 1996, pp. 53-57) hypothesized that chromosomal aberrations can lead to monozygotic (MZ) twinning. However, twinning and chromosomal aberrations increase prenatal mortality and could...... reduce the prevalence of chromosomal aberrations in live-born twins. We compared prevalence proportion ratios (PPR) of chromosomal aberrations and trisomy 21 (T21) in live-born twins versus singletons born in Denmark during 1968-2009. METHODS: We linked the Danish Twin Registry and a 5% random sample...... of all singletons to the Danish Cytogenetic Central Register and calculated PPR adjusted for maternal age for MZ, dizygotic (DZ), and all twins versus singletons. Zygosity was based on questionnaires or genetic markers. RESULTS: No overall difference in risk of chromosomal aberrations or T21 in twins...

Screening of clonal chromosome aberrations present in A-bomb survivors by FISH method

International Nuclear Information System (INIS)

Nakano, Mimako; Kodama, Yoshiaki; Ito, Masahiro; Otaki, Kazuo; Nakamura, Nori

1997-01-01

Significance of FISH method for detection of clonal chromosome aberration was reviewed. A clonal chromosome aberration is derived from one abnormal cell clone and gives the influence on the frequency of the aberration. As well, the size and frequency of the aberration give an important information concerning lymphocyte kinetics. FISH method is meaningful for detection of the clonal aberration. Fifteen kinds of clonal aberrations were detected in A-bomb survivors, of which 10 were specifically detected by the method, indicating that its detection rate was 2-3 time as high as the ordinary method. The results were those on the DNA probe on no.1, no.2 and no.3 chromosomes, which consisting of about 23% of the genome. (K.H.)

Relationship of DNA lesions and their repair to chromosomal aberration production

International Nuclear Information System (INIS)

Bender, M.A.

1979-01-01

Recent work on the roles of specific kinds of DNA lesions and their enzymatic repair systems in the production of chromosomal aberrations seems consistent with a simple molecular model of chromosomal aberrations formation. Evidence from experiments with the human repair-deficient genetic diseases xeroderma pigmentosom, ataxia telangiectasia, and Fanconi's anemia is reviewed in the light of the contributions to aberration production of single and double polynucleotide strand breaks, base damage, polynucleotide strand crosslinks, and pyrimidine cyclobutane dimers

Relationship of DNA lesions and their repair to chromosomal aberration production

Energy Technology Data Exchange (ETDEWEB)

Bender, M.A.

1979-01-01

Recent work on the roles of specific kinds of DNA lesions and their enzymatic repair systems in the production of chromosomal aberrations seems consistent with a simple molecular model of chromosomal aberrations formation. Evidence from experiments with the human repair-deficient genetic diseases xeroderma pigmentosom, ataxia telangiectasia, and Fanconi's anemia is reviewed in the light of the contributions to aberration production of single and double polynucleotide strand breaks, base damage, polynucleotide strand crosslinks, and pyrimidine cyclobutane dimers.

Structural variations of chromosome 1 R from rye cultivar Jingzhouheimai induced by irradiation

International Nuclear Information System (INIS)

Wang Conglei; Zhuang Lifang; Qi Zengjun

2012-01-01

Irradiated with 60 Co γ-rays (12 Gy), the pollen of wheat landrace Huixianhong-Secale cereal cv. Jingzhouheimai DA1R was pollinated to the emasculated spikes of Huixianhong. Analyzed with genomic in situ hybridization GISH using gDNA of rye cv. Jingzhouheimai as a probe, four plants with reciprocal translocation, four plants with large segmental translocation and one plant with distal segmental translocation, one plant with one telocentric chromosome were identified from 33 M 1 seeds. The results showed that the translocation frequency was 30.30% and of the total 11 breakage-fusion events, 1 involved centric regions and 10 involved interstitial regions. The experiment showed that pollen irradiation was an effective method to induce wheat alien chromosomal structural variations which could effectively by used in deletion mapping, chromosomal location of important agronomic genes and development of small segmental translocations with target genes. (authors)

Radition-induced genetic damage in plutella xylostella

International Nuclear Information System (INIS)

Ismail bin Bahari; Mahani binti Mohamad

1993-01-01

Radiation-induced chromosomal aberrations in progenies of irradiated Plutella xylostella was determined in a F1 sterility study. A total of 4 types of crosses (irradiated males against unirradiated females, irradiated females against unirradiated males, both parents irradiated and normal) were made following gamma irradiation at the pupal stage. Testes squash preparations made from F1 male larvae revealed 3 main types of chromosomal abberations induced by doses of 100, 150 and 200 Gy. Results obtained indicate the possibility of using chromosome translocations as the genetic marker

Changes in Sperm Motility and Capacitation Induce Chromosomal Aberration of the Bovine Embryo following Intracytoplasmic Sperm Injection.

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Yoku Kato

Full Text Available Intracytoplasmic sperm injection (ICSI has become the method of choice to treat human male infertility. One of the outstanding problems associated with this technique is our current lack of knowledge concerning the effect of sperm capacitation and motility upon the subsequent development of oocytes following ICSI. In the present study, we first examined the capacitation state of sperm exhibiting normal motility, along with sperm that had been activated, and examined the effect of reactive oxygen species (ROS produced by these sperm types upon embryogenesis following bovine in vitro fertilization (IVF and ICSI. Data showed that activated sperm reduced the chromosomal integrity of IVF/ICSI embryos at the blastocyst stage, while capacitated sperm produced ROS in capacitation media. Secondly, we treated sperm with carbonyl cyanide m-chlorophenyl hydrazine (CCCP, a chemical known to uncouple cell respiration within the mitochondria, and investigated the effect of this treatment upon blastocyst formation and chromosomal integrity at the blastocyst stage. Activated sperm in which the mitochondria had been treated with CCCP reduced levels of chromosomal aberration at the blastocyst stage following ICSI, by reducing mitochondrial activity in activated sperm. In conclusion, these findings suggest that capacitated sperm exhibiting activated motility induced chromosomal aberration during development to the blastocyst stage following ICSI. The injection of sperm exhibiting normal motility, or activated sperm in which mitochondrial activity had been reduced, improved the quality of ICSI-derived embryos. Therefore, the selection of sperm exhibiting progressive motility may not always be better for early embryo development and fetal growth following human ICSI, and that the use of a bovine model may contribute to a deeper understanding of sperm selection for human ICSI embryo development.

Okadaic acid for radiation dose estimation using drug-induced premature chromosome condensation

International Nuclear Information System (INIS)

Wang Chunyan; Zhang Wei; Su Xu

2005-01-01

Objective: To establish simple biological method for high irradiation dose estimation using drug-induced prematurely condensed chromosomes (PCC) aberrations. Methods: Peripheral blood was taken from healthy adults and irradiated by 0, 1, 2, 5, 10, 15, 20 and 25 Gy 60 Co γ-rays. Then the blood samples were cultured for 48 hrs. One hr before the end of culture , okadaic acid was added into culture medium to induce PCC rings, which were counted for each dose point. Results: The yield of PCC rings was increased with the dose of radiation until 20 Gy. Within the range of 1 to 20 Gy, there was a good dose-response relationship between the yield of PCC rings and radiation dose. Conclusion: Compared with the analysis of frequency of dicentrics, the yield of PCC rings could be a good biodosimetry indicator for estimation of high dose irradiation. (authors)

Study of chromosome aberrations on the workers occupationally exposed to thorium and rare earth mixed dust

International Nuclear Information System (INIS)

Zhang Wei; Wang Chunyan; Lv Huiming; Zhang Cuilan; Hao Shuxia; Su Xu; Jia Kejun; Liu Yufei

2008-01-01

Objective: To study the effect of thorium and rare earth mixed dust on chromosome aberrations in the lymphocytes of occupational exposed workers. Methods: Analyses of unstable chromosome aberrations on 53 occupational exposed workers and 58 control workers were carried out by the conventional Giemsa staining method. Fluorescence in situ hybridization method was performed to analyze the chromosome stable aberrations on 10 occupational exposed workers and l0 control workers. Results: The frequencies of chromosomal aberration cells, dicentrics plus rings, total aberrations in exposed workers were significantly higher than those in controls. No significant difference was found in the frequency of acentric aberrations between exposed and non-exposed workers. No significant difference was found in the frequency of translocations between exposed and non-exposed workers. Conclusions: Chronically occupational exposure to thorium and rare earth mixed dust can increase the induction of unstable chromosome aberration, but the increase of stable chromosome aberrations (translocation) can not be observed. (authors)

Dose-response relationship for the induction of structural chromosome aberrations in human spermatozoa after in vitro exposure ti tritium. beta. -rays

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Kamiguchi, Yujiroh; Tateno, Hiroyuki; Mikamo, Kazuya (Asahikawa Medical College (Japan). Department of Biological Sciences)

1990-02-01

THe effects of tritium (HTO) {beta}-rays on human sperm chromosomes were studied using our interspecific in vitro fertilization system between human spermatozoa and zona-free hamster oocytes. Semen samples were treated with media containing 1.53-24.3 mCi/ml HTO for about 80 min. 1290 spermatozoa from the controls and 1842 spermatozoa from the irradiated groups were karyotyped. The incidence of spermatozoa with structural chromosome aberrations increased linearly with increasing dosage. Breakage-type aberrations occurred far more frequently than exchange-type. Chromosome-type aberrations appeared far more frequently than chromatid-ype. All of these types of aberrations showed linear dose-dependent increases. The RBE valus of HTO {beta}-rays relative to X-rays were calculated for the above-mentioned 5 indices, respectively. Their RBE values franged from 1.89 to 3.00 when the absorbed dose was estimated to be the minimum, whereas the values ranged between 1.04 and 1.65 when the absorbed dose was estimated to be the maximum. (author). 15 refs.; 3 figs.; 4 tabs.

DNA and chromosome breaks induced by 123I-estrogen in CHO cells

International Nuclear Information System (INIS)

Schwartz, J.L.

1997-01-01

The effects of the Auger electron-emitting isotope I-123, covalently bound to estrogen, on DNA single- and double-strand breakage and on chromosome breakage was determined in estrogen positive Chinese hamster ovary (CHO-ER) cells. Exposure to the 123 I-estrogen induced both single- and double-strand breaks with a ratio of single- to double-strand breaks of 2.2. The corresponding ratio with 60 Co gamma rays was 15.6. The dose-response was biphasic suggesting that either receptor sites are saturated at high does, or that there is a nonrandom distribution of breaks induced by the 123 I-estrogen. The 123 I-estrogen treatment induced chromosome aberrations with an efficiency of about 1 aberration for each 1,000 disintegrations per cell. This corresponds to the mean lethal dose of 123 I-estrogen for these cells suggesting that the lethal event induced by the Auger electron emitter bound to estrogen is a chromosome aberration. Most of the chromosome-type aberrations were dicentrics and rings, suggesting that 123 I-estrogen-induced chromosome breaks are rejoined. The F-ratio, the ratio of dicentrics to centric rings, was 5.8 ± 1.7, which is similar to that seen with high LET radiations. Their results suggest that I-123 bound to estrogen is an efficient clastogenic agent, that the cytotoxic damage produced by I-123 bound to estrogen is very like high LET-induced damage, and the I-123 in the estrogen-receptor-DNA complex is probably in close proximity to the sugar-phosphate backbone of the DNA

Intrinsic factors that can affect sensitivity to chromosome-aberration induction

International Nuclear Information System (INIS)

Preston, R.J.

1982-01-01

The paper addresses the question, are there individuals who are hypersensitive, or are more likely to be hypersensitive, to the induction of chromosome aberrations by radiation and chemicals. Lymphocytes of persons heterozygous for xeroderma pigmentosum, ataxia telangiectasia, and Fauconi's anemia were subjected to chemical and/or ionizing radiations to determine their sensitivity to chromosome aberration induction. In the majority of cases the sensitivity was intermediate between that of normal individuals and homozygotes for these genes

Study on ionizing radiation to the workers' lymphocyte micronucleus rate and chromosome aberrations

International Nuclear Information System (INIS)

Li Jianhua; Wang Linchao; He Wei

2007-01-01

Objective: To study lymphocyte genetic material of an iron and steel enterprise workers exposed to the ionizing radiation, find out measures to protect their health and reduce ionizing radiation occupation harm. Methods: 342 workers were choseh as the exposed group who worked in an iron and steel enterprise in the beam installment operation, to examine their circumference blood lymphocyte micronucleus rate and the chromosome aberrations, simultaneously select 280 chefs as the control group, The irradiation dosage was determined and statistical analysis was carded out wich the consideration of their length of work and differences in work post. Results: Exposed group: the micronucleus rate masculine gender (MNR), 4 people, the masculine gender pick out rate is 12.87%. The chromosome aberration factor masculine gender (CAF), 12 people, the masculine rate is 3.51%. Control group: MNR 3 people, the asculine gender pick out rate is 1.07%; CAF 2 people, masculine gender rate is 0.72%. Comparing the two groups, every item has the significant difference. Workers in is the exposed group workers have the average exposure dose of 6.73mSv/a, MNR,CAF are illuminated to the dosage have a positive line correlation. They become increased as the job lenght prolongs. The nucleon name, the material calculation and the medical X-radial are responsible for the highest ratio. Conclusion: In iron and steel enterprises, long-time ionizing radiation can cause the workers' circumference blood lymphocyte micronucleus rate and the chromosome aberrations obvious to rise. The beam protection measures strengthened so as to reduce the harms to workers. (authors)

Damage of chromosomes in mouse bone marrow cells after combined treatment with gamma radiation and cyclophosphamide

International Nuclear Information System (INIS)

Rupova, Ivanka

2008-01-01

Full text: Current approaches to successful management of malignancy include combined modalities of treatment with ionizing radiation and anticancer drugs. Together with tumor cells normal tissues and cells are also submitted to the damaging effect of these agents, creating thus a probability for development of secondary neoplastic processes. The aim of the present study was to investigate the rate of chromosome damage at different modalities of combined exposures to gamma irradiation and cyclophosphamide(CY) of mice. Chromosomal aberration frequency in metaphase bone marrow cells was used as a measure to evaluate the effect. Combination treatments with 3 Gy gamma irradiation and 20 mg/kg cyclophosphamide were given at different intervals - simultaneously or at 12 hr interval, in order to establish the conditions and factors influencing the rate of chromosome damage. The distribution of different types of chromosome aberrations, such as chromatid fragments, chromatid exchanges, chromosome fragments and chromosome exchanges was analyzed. The results showed a high synergistic effect at simultaneous treatment with both agents if assessed by the index of aberrations per cell (%). An attempt has been made to suggest a possible explanation of the effects at different combined treatments related to the type of induced chromosomal aberrations. (author)

Analysis of chromosome aberration data by hybrid-scale models

International Nuclear Information System (INIS)

Indrawati, Iwiq; Kumazawa, Shigeru

2000-02-01

This paper presents a new methodology for analyzing data of chromosome aberrations, which is useful to understand the characteristics of dose-response relationships and to construct the calibration curves for the biological dosimetry. The hybrid scale of linear and logarithmic scales brings a particular plotting paper, where the normal section paper, two types of semi-log papers and the log-log paper are continuously connected. The hybrid-hybrid plotting paper may contain nine kinds of linear relationships, and these are conveniently called hybrid scale models. One can systematically select the best-fit model among the nine models by among the conditions for a straight line of data points. A biological interpretation is possible with some hybrid-scale models. In this report, the hybrid scale models were applied to separately reported data on chromosome aberrations in human lymphocytes as well as on chromosome breaks in Tradescantia. The results proved that the proposed models fit the data better than the linear-quadratic model, despite the demerit of the increased number of model parameters. We showed that the hybrid-hybrid model (both variables of dose and response using the hybrid scale) provides the best-fit straight lines to be used as the reliable and readable calibration curves of chromosome aberrations. (author)

Cytogenetic effects of irradiation in epithelial kidney cells of monkeys and possibilities of using these data for evaluation of chromosome aberration level in kidneys of persons subjected to radiotherapy

International Nuclear Information System (INIS)

Machavariani, M.G.

1983-01-01

Data on somatic mutagenesis, induced by radiation, in epithelial kidney cells of monkeys are presented. It is noted that chromosomal aberrations in the kideny cells of monkeys can be indicator of estimation of hUman kideny state during radiotherapy

Chromosome aberration analysis in peripheral lymphocytes of Gulf war and Balkans war veterans

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Schroeder, H.; Heimers, A.; Frentzel-Beyme, R.; Schott, A.; Hoffmann, W

2003-07-01

Chromosome aberrations and sister chromatid exchanges (SCEs) were determined in standard peripheral lymphocyte metaphase preparations of 13 British Gulf War veterans, two veterans of the recent war in the Balkans, and one veteran of both wars. All 16 volunteers suspect exposures to depleted uranium while deployed at the two different theatres of war in 1990 and later on. The Bremen laboratory control served as a reference in this study. Compared with this control there was a statistically significant increase in the frequency of dicentric chromosomes (dic) and centric ring chromosomes (cR) in the veterans' group, indicating a previous exposure to ionising radiation. The statistically significant overdispersion of dic and cR indicates non-uniform irradiation as would be expected after non-uniform exposure and/or exposure to radiation with a high linear energy transfer. The frequency of SCEs was decreased when compared with the laboratory control. (author)

Chromosome aberration analysis in peripheral lymphocytes of Gulf war and Balkans war veterans

International Nuclear Information System (INIS)

Schroeder, H.; Heimers, A.; Frentzel-Beyme, R.; Schott, A.; Hoffmann, W.

2003-01-01

Chromosome aberrations and sister chromatid exchanges (SCEs) were determined in standard peripheral lymphocyte metaphase preparations of 13 British Gulf War veterans, two veterans of the recent war in the Balkans, and one veteran of both wars. All 16 volunteers suspect exposures to depleted uranium while deployed at the two different theatres of war in 1990 and later on. The Bremen laboratory control served as a reference in this study. Compared with this control there was a statistically significant increase in the frequency of dicentric chromosomes (dic) and centric ring chromosomes (cR) in the veterans' group, indicating a previous exposure to ionising radiation. The statistically significant overdispersion of dic and cR indicates non-uniform irradiation as would be expected after non-uniform exposure and/or exposure to radiation with a high linear energy transfer. The frequency of SCEs was decreased when compared with the laboratory control. (author)

Comparative retention of fission fragment 147Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells

International Nuclear Information System (INIS)

Zhu Shoupeng; Zheng Siying; Wang Liuyi; Yang Shujin

1989-01-01

The purpose of the present study is to ascertain comparative retention of fission fragment 147 Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells. The results indicated that retention of 147 Pm in regenerated liver was about 700 times than in fetal liver. The cumulative absorption dose in regenerated liver was about 2.87 Gy, while in fetal liver-only 0.004 Gy. Under the same conditions, the incidence rate of chromosome aberrations in regenerated liver cells induced by 147 Pm was 50.2%, and in fetal liver cells-about 28.3%. It should be concluded that the radiosensitivity to 147 Pm was not uniform among the regenerated and fetal liver cells. The study suggested that fetal liver cells show to be more radiosensitive to 147 Pm than regenerated liver cells. Among the type of aberrations in both cells induced by 147 Pm, chromatid breakages were predominant, accompanied with a few chromosome breakages

Chromosome break points of T-lymphocytes from atomic bomb survivors

International Nuclear Information System (INIS)

Tanaka, Kimio; Kamada, Nanao; Kuramoto, Atsushi; Ohkita, Takeshi

1980-01-01

Chromosome break points of T-lymphocytes were investigated for 9 atomic bomb survivors estimated to be irradiated with 100 - 630 red. Chromosome aberration was found in 199 cells out of 678 cells investigated, with non-random distribution. The types of the chromosome aberration were, transfer: 56%, deficit: 38%, additional abnormality 3%, and reverse: 2%. High and low incidence of chromosome aberrations were observed at the chromosome numbers of 22, 21, and 13, and 11, 12, and 4, respectively. The aberration numbers per arm were high in 22q, 21q, and 18p and low in 11q, 5p, and 12q. For the distribution of aberration number within a chromosome, 50.7% was observed at the terminal portion and 73% was at the pale band appeared by Q-partial-stain method, suggesting the non-random distribution. The incidence of aberration number in 22q was statistically significant (P 1 chromosome in chronic myelocytic leukemia. The non-random distribution of chromosome break points seemed to reflect the selection effect since irradiation. (Nakanishi, T.)

Effect of ethyl methanesulphonate and X-irradiation on the spermatocyte chromosomes of the grasshopper, Gesonula punctifrons

International Nuclear Information System (INIS)

Ghosh, Mita; Majumdar, K.C.; Duttagupta, A.K.

1977-01-01

Present investigation was performed to find out the effect of ethyl methanesulfonate (EMS) and X-irradiation on the meiotic cells of the grasshopper Gesonula punctifrons. Adult male grasshoppers were administered EMS (intraperitoneal injection) with one of the following concentration : 0.05%, 0.05% + 0.05%, 0.1%, 0.2%. Only 0.002 ml of required concentration were injected/animal and irradiated with 200R of X-ray in one acute dose/animal as per experimental schedule. Controls were injected with distilled water with a quantity 0.002 ml/animal. Treated and control animals were sacrificed 24 hours and 48 hours after treatment and the dividing spermatocytes were analysed for chromosomal aberrations. It was shown that EMS had stage spcificity as compared to the 200R of X-ray on the production of chromosome aberrations. Combined treatment of X-ray and EMS showed an additive effect compared to the individual effect of X-irradiation or EMS. (author)

Evaluation of Resveratrol as Radioprotector Against Radiation-Induced Genetic Damage in Mice

International Nuclear Information System (INIS)

Hasan, N.H.A.; El-Dawy, H.A.; Salah, A.E.

2014-01-01

The objective of this study is to give more information about the role of resveratrol as radioprotector. The radioprotective effect of resveratrol against radiation-induced chromosomal aberrations was evaluated in mice by intraperitoneal administration of resveratrol (50 mg/kg body weight) 30 minute priror to whole body gamma irradiation (4 Gy).The data obtained from the present study indicated that resveratrol induced significant decline in the total chromosomal aberrations when injected before gamma irradiation as compared with the gamma irradiated group, but still significantly higher than that of control group.

Cytotoxicity and genotoxicity of UVA irradiation in Chinese hamster ovary cells measured by specific locus mutations, sister chromatid exchanges and chromosome aberrations

International Nuclear Information System (INIS)

Lundgren, Karsten; Wulf, H.C.

1988-01-01

The increasing use of artificial UVA (320-400 nm) suntanning devices has brought attention to possible hazardous effects of UVA. In contrast with earlier studies, several groups recently have described that UVA possibly is mutagenic. We evaluate the genotoxic properties of broad band UVA using CHO cells and three different assays: specific locus (HGPRT) mutations, chromosome aberrations, and sister chromatid exchanges (SCEs). The UVA-source was an UVASUN 2000 S (Mutzhas), emitting UVA above 340 nm. The survival curve of the cells exhibited a shoulder up to 200 kJ/m 2 , that was followed by exponential killing at higher fluences. Mutations were induced linearly in the fluence range of 0-200 kJ/m 2 to a level seven fold higher than the spontaneous, followed by a decrease at fluences above 300 kJ/m 2 . Over the total range of tested fluences (0-300 kJ/m 2 ) a linear dose-response relationship was observed for UVA-induced SCEs. A significantly higher percentage of the cells showed chromosomes with aberrations at the higher levels of exposure (200, 300 and 400 kJ/m 2 ), but no dose response was demonstrated. Our results confirm recent findings showing that UVA is mutagenic in mammalian cells and suggest that UVA exposure may contribute to the total burden of genetic damage caused by exposure to ultraviolet light. (author)

Chromosome aberrations in cultured skin cells obtained from atomic bomb survivors

International Nuclear Information System (INIS)

Honda, Takeo; Sadamori, Naoki.

1989-01-01

Skin specimens were obtained from 11 A-bomb survivors, 10 of whom had been exposed at ≤2300 m from the hypocenter, and 7 non-exposed controls. There was a higher frequency (12%, 147/1222 cells) of chromosome aberrations in the exposed group compared with 1.2% (4/341 cells) in the control group. This suggests that aberrant cells are still present in the skin tissue 40 years or more after the bombing. Of 147 cells, 136 cells (91.3%) showed translocation of chromosome. Other aberrations, such as inversion, deletion, dicentric chromosome and acentric fragment, were observed in only 3.8%. These aberrant cells tended to be observed in A-bomb survivors exposed to high doses and with a history of severe acute symptoms. One hundred and twenty two (83%) of 136 aberrant cells were obtained from 3 A-bomb survivors, which has important implications for marked proliferation of specific clone cells. In an analysis by B-band staining technique for the 122 cells, band sites of break point were found to correspond to loci of protooncogenes, suggesting the involvement in aggressive proliferation of clone cells. (Namekawa, K)

Risk of cancer in an occupationally exposed cohort with increased level of chromosomal aberrations.

Science.gov (United States)

Smerhovsky, Z; Landa, K; Rössner, P; Brabec, M; Zudova, Z; Hola, N; Pokorna, Z; Mareckova, J; Hurychova, D

2001-01-01

We used cytogenetic analysis to carry out a cohort study in which the major objective was to test the association between frequency of chromosomal aberrations and subsequent risk of cancer. In spite of the extensive use of the cytogenetic analysis of human peripheral blood lymphocytes in biomonitoring of exposure to various mutagens and carcinogens on an ecologic level, the long-term effects of an increased frequency of chromosomal aberrations in individuals are still uncertain. Few epidemiologic studies have addressed this issue, and a moderate risk of cancer in individuals with an elevated frequency of chromosomal aberrations has been observed. In the present study, we analyzed data on 8,962 cytogenetic tests and 3,973 subjects. We found a significant and strong association between the frequency of chromosomal aberrations and cancer incidence in a group of miners exposed to radon, where a 1% increase in frequency of chromosomal aberrations was followed by a 64% increase in risk of cancer (p < 0.000). In contrast, the collected data are inadequate for a critical evaluation of the association with exposure to other chemicals. PMID:11171523

Influence of age and gender in response to {gamma}-radiation in Portuguese individuals using chromosomal aberration assay - Preliminary findings

Energy Technology Data Exchange (ETDEWEB)

Martins, V.; Antunes, A.C. [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Dosimetry and Radiobiology Group, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal); Cardoso, J.; Santos, L. [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Metrology Laboratory of Ionizing Radiation, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal); Gil, O. Monteiro, E-mail: octavia.gil@itn.pt [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Dosimetry and Radiobiology Group, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal)

2011-09-15

Cytogenetic indicators are widely used in radiobiology to evaluate effects of ionizing radiation since dicentric chromosomes (Dic) are almost exclusively induced by ionizing radiation, and spontaneous frequency of Dic is very low in the healthy general population (about one Dic per 1000 cells). A particular interest of biodosimetry has been not only to obtain absorbed dose estimates using adequate calibration curves, under the assumption that all individuals respond equally to radiation-induced chromosome aberrations, but also to find a way to demonstrate inter-individual radiosensitivity and a possible correlation with age and gender. Thus, the objective of this preliminary work was the evaluation of the influence of age and gender on the outcome of cytogenetic biomarkers after {gamma}-irradiation. Samples of peripheral blood lymphocytes from six healthy, non-smoker, donors from both genders (three men and three women), in the range of 20 to 49 years, were irradiated with doses from 0 Gy to 3 Gy air kerma, using a {sup 60}Co gamma rays source with a dose rate from 170-180 mGy/min. A clear dose-dependent increase in terms of aberrant cells excluding gaps (ACEG) and Dic was observed for all donors. Our preliminary results suggest, in the higher dose level evaluated (3 Gy), a larger intervariability among individuals for Dic, with females apparently more sensitive than males (P<0.05). Considering the different age groups, male donors showed a decrease, with age, for Dic and ACEG at the higher dose and also, for the background level, in case of ACEG. Future work will consider the study of more individuals, from both genders and different ages, in order to verify if this tendency persists and to enable the implementation of a dose-response calibration curve at Instituto Tecnologico e Nuclear for the Portuguese population, to quantify the biological dose in case of a radiological accident or emergency.

Influence of age and gender in response to γ-radiation in Portuguese individuals using chromosomal aberration assay - Preliminary findings

International Nuclear Information System (INIS)

Martins, V.; Antunes, A.C.; Cardoso, J.; Santos, L.; Gil, O. Monteiro

2011-01-01

Cytogenetic indicators are widely used in radiobiology to evaluate effects of ionizing radiation since dicentric chromosomes (Dic) are almost exclusively induced by ionizing radiation, and spontaneous frequency of Dic is very low in the healthy general population (about one Dic per 1000 cells). A particular interest of biodosimetry has been not only to obtain absorbed dose estimates using adequate calibration curves, under the assumption that all individuals respond equally to radiation-induced chromosome aberrations, but also to find a way to demonstrate inter-individual radiosensitivity and a possible correlation with age and gender. Thus, the objective of this preliminary work was the evaluation of the influence of age and gender on the outcome of cytogenetic biomarkers after γ-irradiation. Samples of peripheral blood lymphocytes from six healthy, non-smoker, donors from both genders (three men and three women), in the range of 20 to 49 years, were irradiated with doses from 0 Gy to 3 Gy air kerma, using a 60 Co gamma rays source with a dose rate from 170-180 mGy/min. A clear dose-dependent increase in terms of aberrant cells excluding gaps (ACEG) and Dic was observed for all donors. Our preliminary results suggest, in the higher dose level evaluated (3 Gy), a larger intervariability among individuals for Dic, with females apparently more sensitive than males (P<0.05). Considering the different age groups, male donors showed a decrease, with age, for Dic and ACEG at the higher dose and also, for the background level, in case of ACEG. Future work will consider the study of more individuals, from both genders and different ages, in order to verify if this tendency persists and to enable the implementation of a dose-response calibration curve at Instituto Tecnologico e Nuclear for the Portuguese population, to quantify the biological dose in case of a radiological accident or emergency.

Dose response relationship for unstable-type chromosome aberration rate of spleen cells from mice continuously exposed to low-dose-rate gamma-rays

International Nuclear Information System (INIS)

Tanaka, Kimio; Khoda, Atsushi; Ichinohe, Kazuaki; Oghiso, Yoichi

2007-01-01

It has been reported that people who are chronically exposed to radiation such as nuclear facility workers and medical radiologists have slightly higher incidences of chromosome aberrations than non-exposed people. However, chronological changes of chromosome aberration rates related to accumulated doses and dose-rates for low dose-rate radiation exposures have not been well studied. Precise analyses of human populations are quite limited because confounding factors influence the results. For this reason, animal experiments are important for analyses. Mice were continuously exposed to gamma-rays at 400 mGy/22 hr/day for 10 days, 20 mGy/22 hr/day for about 400 days, and 1 mGy/22 hr/day for about 615 days under SPF conditions. Chronological changes of unstable-type chromosome aberration rates of spleen cells were observed along with accumulated doses at the middle dose rate and the two low-dose rates by conventional Giemsa-staining method. Aberrations such as dicentric chromosome, ring chromosome and fragment increased in a two-phase manner within 0-1.2 Gy and 2-8 Gy at 20 mGy/22 hr/day. They slightly increased up to 0.5 Gy at 1 mGy/22 hr/day. Aberration rates for 1, 2, 8 Gy at the 20 mGy/22 hr/day and for 0.5 Gy at 1 mGy/22 hr/day were 5.1, 9.6, 13.9 and 2.2 times higher than those of age-matched, non-irradiated control mice, respectively. Chromosome aberration rates at 400 mGy/22 hr/day were 2.7 times higher than that of 20 mGy/22 hr/day for the same total dose of 1.2 Gy. The results that unstable-type chromosome aberrations increased with accumulated dose of the low-dose rate radiation will be important to establish biological dosimetry for people who are chronically exposed to radiation. (author)

Chromosome aberration analysis in a group of workers who dealt with radioluminious paints

International Nuclear Information System (INIS)

Markovicj, B.; Panov, D.; Joksicj, G.

1988-01-01

By using radiotoxicology tests (H-3 analysis in urine) in a group of workers who dealt with radioluminous paints, the presence of internal contamination was discovered. Moreover, the frequency of chromosome aberrations increased as well. The observation of chromosome aberrations was therefore continued for next 6 and 9 months. Chromosome aberrations still exist even 6 months after taking the subject away from the endangered workplace, but nine months after the incident they mostly disappear from peripheral blood. Biodosimetry investigations show that dose estimates were in the range 0,12 - 0,595 Gy. (author). 3 refs.; 1 tab

Effects of long-term radiation exposure on chromosomal aberrations in radiological technologists

International Nuclear Information System (INIS)

Kumagai, Etsuko; Onomichi, Mitsukazu; Tanaka, Ryuji; Kumagai, Takashi; Sawada, Shozo.

1990-01-01

Chromosomal aberrations in the lymphocytes of radiation technologists (RT) were analyzed by the trypsin G-banding method to study the late effects of long-term exposure to low doses of radiation. Structural aberrations were identified in 384 (2.5%) of 15442 cells analyzed from 53 RT as compared to 177 (1.6%) of 11136 cells from 36 healthy controls. Stable aberrations were the most frequent in both groups and were either translocations or deletions. Unstable aberrations were mainly acentric fragments in both groups. The frequency of translocations and acentric fragments was significantly higher in the RT than in the controls and was highest in the RT over 50 years. The highest frequency observed in the >50 age group was attributed to the unknown for cumulative dose prior to introduction of film badges. Frequency of chromosomal aberrations correlated with the estimated dose from the film badges and years of experience of each RT based on the equation y=0.22+0.37D+4.35D 2 , where y is overall frequency of chromosomal aberrations and D is the estimated radiation dose in Sv. (author)

Relationship between X-ray irradiation and chromosomal damage in bone marrow tissue of mice

International Nuclear Information System (INIS)

Chaubey, R.C.; George, K.P.; Sundaram, K.

1976-01-01

X-ray induced chromosomal damage in bone-marrow tissue of male mice was studied using micronucleus technique. Dose response relationship was evaluated. Male Swiss mice received whole body x-ray irradiation at different doses from 25-1000 rads. Animals were sacrificed at the end of 24 hours, bone-marrow smears were made and stained in May-Grunwald-Giemsa. The preparatians were scored for the following types of aberrations: micronuclei in young erythocytes-polychromatic cells and in the mature erythrocytes-normechromatic cells. A dose dependent increase in the frequency of micronuclei in polychromatic cells up to a dose of 100 rads was observed. In addition the effect of post-irradiation duration on the frequency of micronuclei in polychromatic and normochromatic cells were studied. Male Swiss mice were exposed to 200 rads x-rays and were then sacrificed at different time intervals after irradiation and bone-marrow preparations were made and scored. Maximum polychromatic cells with micronuclei were observed in 24 hours post-irradiated animals, thereafter a decrease in the frequency of polychromatic cells with micronuclei was observed in 40 hours post irradiated animals. (author

Computer aided analysis of additional chromosome aberrations in Philadelphia chromosome positive acute lymphoblastic leukaemia using a simplified computer readable cytogenetic notation

Directory of Open Access Journals (Sweden)

Mohr Brigitte

2003-01-01

Full Text Available Abstract Background The analysis of complex cytogenetic databases of distinct leukaemia entities may help to detect rare recurring chromosome aberrations, minimal common regions of gains and losses, and also hot spots of genomic rearrangements. The patterns of the karyotype alterations may provide insights into the genetic pathways of disease progression. Results We developed a simplified computer readable cytogenetic notation (SCCN by which chromosome findings are normalised at a resolution of 400 bands. Lost or gained chromosomes or chromosome segments are specified in detail, and ranges of chromosome breakpoint assignments are recorded. Software modules were written to summarise the recorded chromosome changes with regard to the respective chromosome involvement. To assess the degree of karyotype alterations the ploidy levels and numbers of numerical and structural changes were recorded separately, and summarised in a complex karyotype aberration score (CKAS. The SCCN and CKAS were used to analyse the extend and the spectrum of additional chromosome aberrations in 94 patients with Philadelphia chromosome positive (Ph-positive acute lymphoblastic leukemia (ALL and secondary chromosome anomalies. Dosage changes of chromosomal material represented 92.1% of all additional events. Recurring regions of chromosome losses were identified. Structural rearrangements affecting (pericentromeric chromosome regions were recorded in 24.6% of the cases. Conclusions SCCN and CKAS provide unifying elements between karyotypes and computer processable data formats. They proved to be useful in the investigation of additional chromosome aberrations in Ph-positive ALL, and may represent a step towards full automation of the analysis of large and complex karyotype databases.

Municipal landfill leachates induced chromosome aberrations in rat ...

African Journals Online (AJOL)

Physico-chemical and heavy metal analysis of the test samples showed that they contained high concentrations of toxic anions and cations that are capable of inducing mutation in living cells. The interaction of these constituents with the genetic material in the bone marrow cells of rat caused the observed chromosome ...

The effect of defective DNA double-strand break repair on mutations and chromosome aberrations in the Chinese hamster cell mutant XR-V15B

International Nuclear Information System (INIS)

Helbig, R.; Speit, G.; Zdzienicka, M.Z.

1995-01-01

The radiosensitive Chinese hamster cell line XR-V15B was used to study the effect of decreased rejoining of DNA double-strand breaks (DSBs) on gene mutations and chromosome aberrations. XR-V15B cells are hypersensitive to the cytotoxic effects of neocarzinostatin (NCS) and methyl methanesulfonate (MMS). Both mutagens induced more chromosome aberrations in XR-V15B cells than in the parental cell strain. The clastogenic action of NCS was characterized by the induction of predominantly chromosome-type aberrations in cells of both strains, whereas MMS induced mainly chromatid aberrations. The frequency of induced gene mutations at the hprt locus was not increased compared to the parental V79 cells when considering the same survival level. Molecular analysis by multiplex polymerase chain reaction (PCR) of mutants induced by NCS revealed a high frequency of deletions in cells of both cell lines. Methyl methane-sulfonate induced mainly mutations without visible change in the PCR pattern, which probably represent point mutations. Our findings suggest a link between a defect in DNA DSB repair and increased cytotoxic and clastogenic effects. However, a decreased ability to rejoin DNA DSBs does not seem to influence the incidence and types of gene mutations at the hprt locus induced by NCS and MMS. 28 refs., 4 figs., 3 tabs

Yield of chromosomal aberrations and recoil particle range in Chineses hamster fibroblasts exposed to 8.5 to 500 keV neutrons