The analysis of distribution of the chromosome aberration breakpoints from medical diagnostic X-ray workers

International Nuclear Information System (INIS)

Wang Qin; Li Jin; Tang Weisheng; Wang Zhiquan

2003-01-01

Objective: To analyze the distribution of the chromosome aberration breakpoints from medical diagnostic x-ray workers. Methods: The breakpoints of lymphocyte chromosomes are analyzed using G-banding. Results: There are 146 breakpoints among 3545 metaphase in 37 cases of X-ray workers. There are statistically significant differences between observed values and expected values (χ 2 =42.82, df=23, P 0.05). Conclusion: The chromosome aberration breakpoints of medical diagnostic X-ray workers are non-random. The observed values of breakpoint numbers are higher than those of the expected values in 7 and 14 chromosomes (P<0.05)

Geant4.10 simulation of geometric model for metaphase chromosome

Energy Technology Data Exchange (ETDEWEB)

Rafat-Motavalli, L., E-mail: rafat@um.ac.ir; Miri-Hakimabad, H.; Bakhtiyari, E.

2016-04-01

In this paper, a geometric model of metaphase chromosome is explained. The model is constructed according to the packing ratio and dimension of the structure from nucleosome up to chromosome. A B-DNA base pair is used to construct 200 base pairs of nucleosomes. Each chromatin fiber loop, which is the unit of repeat, has 49,200 bp. This geometry is entered in Geant4.10 Monte Carlo simulation toolkit and can be extended to the whole metaphase chromosomes and any application in which a DNA geometrical model is needed. The chromosome base pairs, chromosome length, and relative length of chromosomes are calculated. The calculated relative length is compared to the relative length of human chromosomes.

Geant4.10 simulation of geometric model for metaphase chromosome

International Nuclear Information System (INIS)

Rafat-Motavalli, L.; Miri-Hakimabad, H.; Bakhtiyari, E.

2016-01-01

In this paper, a geometric model of metaphase chromosome is explained. The model is constructed according to the packing ratio and dimension of the structure from nucleosome up to chromosome. A B-DNA base pair is used to construct 200 base pairs of nucleosomes. Each chromatin fiber loop, which is the unit of repeat, has 49,200 bp. This geometry is entered in Geant4.10 Monte Carlo simulation toolkit and can be extended to the whole metaphase chromosomes and any application in which a DNA geometrical model is needed. The chromosome base pairs, chromosome length, and relative length of chromosomes are calculated. The calculated relative length is compared to the relative length of human chromosomes.

Automatic Metaphase Finding by Inter-Chromosome Extrema Profile Analysis

National Research Council Canada - National Science Library

Vega-Alvarado, Leticia

2001-01-01

...-level inter-chromosome coarseness features in microscopic images of metaphase spreads, and allows to quantity the texture of the cytological objects analysing the intensity profile between chromosome...

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

An automatic system to search, acquire, and analyse chromosomal aberrations obtained using FISH technique

International Nuclear Information System (INIS)

Esposito, R.D.

2003-01-01

Full text: Chromosomal aberrations (CA) analysis in peripheral blood lymphocytes is useful both in prenatal diagnoses and cancer cytogenetics, as well as in toxicology to determine the biologically significant dose of specific, both physical and chemical, genotoxic agents to which an individual is exposed. A useful cytogenetic technique for CAs analysis is Fluorescence-in-situ-Hybridization (FISH) which simplifies the automatic Identification and characterisation of aberrations, allowing the visualisation of chromosomes as bright signals on a dark background, and a fast analysis of stable aberrations, which are particularly interesting for late effects. The main limitation of CA analysis is the rarity with which these events occur, and therefore the time necessary to single out a statistically significant number of aberrant cells. In order to address this problem, a prototype system, capable of automatically searching, acquiring, and recognising chromosomal images of samples prepared using FISH, has been developed. The system is able to score large number of samples in a reasonable time using predefined search criteria. The system is based on the appropriately implemented and characterised automatic metaphase finder Metafer4 (MetaSystems), coupled with a specific module for the acquisition of high magnification metaphase images with any combination of fluorescence filters. These images are then analysed and classified using our software. The prototype is currently capable of separating normal metaphase images from presumed aberrant ones. This system is currently in use in our laboratories both by ourselves and by other researchers not involved in its development, in order to carry out analyses of CAs induced by ionising radiation. The prototype allows simple acquisition and management of large quantities of images and makes it possible to carry out methodological studies -such as the comparison of results obtained by different operators- as well as increasing the

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)

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.)

AFM picking-up manipulation of the metaphase chromosome fragment by using the tweezers-type probe

International Nuclear Information System (INIS)

Yamanaka, Keiichiro; Saito, Masato; Shichiri, Motoharu; Sugiyama, Sigeru; Takamura, Yuzuru; Hashiguchi, Gen; Tamiya, Eiichi

2008-01-01

We have studied the development of a new procedure based on atomic force microscopy (AFM) for the analysis of metaphase chromosome. The aim of this study was to obtain detailed information about the specific locations of genes on the metaphase chromosome. In this research, we performed the manipulation of the metaphase chromosome by using novel AFM probes to obtain chromosome fragments of a smaller size than the ones obtained using the conventional methods, such as glass microneedles. We could pick up the fragment of the metaphase chromosome dissected by the knife-edged probe by using our tweezers-type probe

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)

In situ hybridization of iodinated 5S and 18/25S RNA to Vicia faba metaphase chromosomes

International Nuclear Information System (INIS)

Schubert, I.; Baeumlein, H.; Wobus, U.

1978-01-01

In vitro labelled 125 I ribosomal RNA fractions (18/25S and 5S) were in situ hybridized to metaphase chromosomes of a reconstructed karyotype of Vicia faba (characterized by two translocations and one pericentric inversion, each being present homozygously). The sites of 18S and 25S RNA were found to be confined to the nucleolus organizing secondary constriction. Two loci of 5S RNA were recognized on the satellite of nucleolus bearing chromosome. Possible correlations between the location of ribosomal genes, heterochromatic G-bands and clusters of mutagen induced chromatid aberrations are discussed. (author)

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

Incidence of chromosomal aberrations and micronuclei in cave tour guides.

Science.gov (United States)

Bilban, M; Bilban-Jakopin, C; Vrhovec, S

2001-01-01

An analysis of structural chromosomal aberrations (SCA) and micronucleus tests (MN) were performed in 38 subjects, cave tour guides and in appropriate control group. The dominant type of chromosomal aberrations in tourist guides were chromosomal breaks (0.013 per cell) and acentric fragments (0.011 per cell). In the control group, these aberrations were present up to 0.008 on cells. Considering the analysed cells of the guides in total (33,556), the incidence of dicentric and rings range is below 0.0008 on cells, even though three dicentric and ring chromosoms were found already in the first 1000 in vitro metaphases of some guides. Only 0.0003 dicentrics and neither other translocations were found in control group (ambiental exposure). The incidence of micronuclei in cytokinesis blocked lymphocytes ranged from 12-32 per 500 CB cells in the cave tour guides and from 4-11 per 500 CB cells in control group. Measurements of radon and its daughters were performed at different locations in the cave. Annual doses from 40-60 mSv were estimated per 2000 work hours for cave guides. The changes found in the genome of somatic cells may be related to the exposure doses of radon and its daughters, although smoking should not be ignored.

Retrospective Dose Reconstruction for Medical Diagnostic X Ray Workers in China using Stable Chromosome Aberrations

International Nuclear Information System (INIS)

Wang, Q.; Liu, P.; Li, J.; Wang, Q.; Tang, S.; Sun, M.; Wang, L.; Aoyama, T.; Sugahara, T.

1998-01-01

The chromosome rearrangements in medical diagnostic X ray workers were analysed using the G-banding technique and evaluated collectively in accumulated doses. A total of 9102 metaphase spreads from 84 medical diagnostic X ray workers and 17 controls were scored. The results showed that: (1) the frequencies of translocation, stable chromosome aberration and total aberration in X ray workers were significantly higher than those of controls (P < 0.05 γ 0.005), unstable chromosome aberrations (including dicentric and acentric aberration) tended upwards; (2) the main aberration in stable aberrations was reciprocal translocation; (3) the stable aberration predominated strikingly in total aberrations. The medical diagnostic X ray workers were divided into three groups according to calendar year of entry. The data showed that the frequencies of translocation, stable aberration and total aberration increased with earlier year of entry, especially in two groups who started working before 1970. According to the equation recommended by Straume et al, linear coefficient (α) in the linear quadratic model provided by Fernandez's experiment, their collective accumulation doses calculated were 0.53, 0.26 and 0.06 Gy for calendar year of entry before 1960, 1960-1969, and after 1970, in X ray workers, respectively. (author)

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

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.

Computer graphics of SEM images facilitate recognition of chromosome position in isolated human metaphase plates.

Science.gov (United States)

Hodge, L D; Barrett, J M; Welter, D A

1995-04-01

There is general agreement that at the time of mitosis chromosomes occupy precise positions and that these positions likely affect subsequent nuclear function in interphase. However, before such ideas can be investigated in human cells, it is necessary to determine first the precise position of each chromosome with regard to its neighbors. It has occurred to us that stereo images, produced by scanning electron microscopy, of isolated metaphase plates could form the basis whereby these positions could be ascertained. In this paper we describe a computer graphic technique that permits us to keep track of individual chromosomes in a metaphase plate and to compare chromosome positions in different metaphase plates. Moreover, the computer graphics provide permanent, easily manipulated, rapid recall of stored chromosome profiles. These advantages are demonstrated by a comparison of the relative position of group A-specific and groups D- and G-specific chromosomes to the full complement of chromosomes in metaphase plates isolated from a nearly triploid human-derived cell (HeLa S3) to a hypo-diploid human fetal lung cell.

Mapping EBNA-1 Domains Involved in Binding to Metaphase Chromosomes

Science.gov (United States)

Marechal, Vincent; Dehee, Axelle; Chikhi-Brachet, Roxane; Piolot, Tristan; Coppey-Moisan, Maité; Nicolas, Jean-Claude

1999-01-01

The Epstein-Barr virus (EBV) genome can persist in dividing human B cells as multicopy circular episomes. Viral episomes replicate in synchrony with host cell DNA and are maintained at a relatively constant copy number for a long time. Only two viral elements, the replication origin OriP and the EBNA-1 protein, are required for the persistence of viral genomes during latency. EBNA-1 activates OriP during the S phase and may also contribute to the partition and/or retention of viral genomes during mitosis. Indeed, EBNA-1 has been shown to interact with mitotic chromatin. Moreover, viral genomes are noncovalently associated with metaphase chromosomes. This suggests that EBNA-1 may facilitate the anchorage of viral genomes on cellular chromosomes, thus ensuring proper partition and retention. In the present paper, we have investigated the chromosome-binding activity of EBV EBNA-1, herpesvirus papio (HVP) EBNA-1, and various derivatives of EBV EBNA-1, fused to a variant of the green fluorescent protein. The results show that binding to metaphase chromosomes is a common property of EBV and HVP EBNA-1. Further studies indicated that at least three independent domains (CBS-1, -2, and -3) mediate EBNA-1 binding to metaphase chromosomes. In agreement with the anchorage model, two of these domains mapped to a region that has been previously demonstrated to be required for the long-term persistence of OriP-containing plasmids. PMID:10196336

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)

Chromosomal aberrations in Sigmodon hispidus from a Superfund site

International Nuclear Information System (INIS)

Bowers, B.; McBee, K.; Lochmiller, R.; Burks, S.; Qualls, C.

1995-01-01

Cotton rats (Sigmodon hispidus) were collected from an EPA Superfund site located on an abandoned oil refinery. Three trapping grids were located on the refinery and three similar grids were located at uncontaminated localities which served as reference sites. Bone marrow metaphase chromosome preparations were examined for chromosomal damage. For each individual, 50 cells were scored for six classes of chromosomal lesions. For the fall 1991 trapping period, mean number of aberrant cells per individual was 2.33, 0.85, and 1.50 for the three Superfund grids., Mean number of aberrant cells per individual was 2.55, 2.55, and 2.12 from the reference grids. Mean number of lesions per cell was 2.77, 0.86, and 1.9 from the Superfund grids, and 3.55, 2.77, and 2.50 from the reference grids. For the spring 1992 trapping period, more damage was observed in animals from both Superfund and reference sites; however, animals from Superfund grids had more damage than animals from reference grids. Mean number of aberrant cells per individual was 3.50, 3.25, and 3.70 from the Superfund grids, and 2.40, 2.11, and 1.40 from the reference grids. Mean number of lesions per cell was 4.80, 4.25, and 5.50 from the Superfund grids, and 2.60, 2.33, and 1.50 from the reference grids. These data suggest animals may be more susceptible to chromosomal damage during winter months, and animals from the Superfund grids appear to be more severely affected than animals from reference grids

Chromosome mapping by FISH to metaphase and interphase nuclei. Final report

Energy Technology Data Exchange (ETDEWEB)

Trask, B.

1997-08-01

The overall specific aims of this project were: (1) to determine the large-scale structure of interphase and metaphase chromosomes, in order to establish new capabilities for genome mapping by fluorescence in situ hybridization (FISH); (2) to detect chromosome abnormalities associated with genetic disease and map DNA sequences relative to them in order to facilitate the identification of new genes with disease-causing mutations; (3) to establish medium resolution physical maps of selected chromosomal regions using a combined metaphase and interphase mapping strategy and to corroborate physical and genetic maps and integrate these maps with the cytogenetic map; (4) to analyze the polymorphism and sequence evolution of subtelomeric regions of human chromosomes; (5) to establish a state-of-the-art FISH and image processing facility in the Department of Molecular Biotechnology, University of Washington, in order to map DNA sequences rapidly and accurately to benefit the Human Genome Project.

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.)

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)

Intra-chromosomal aberrations observed after high-LET radiation exposure in vivo using a state-of-the-art cytogenetic technique

International Nuclear Information System (INIS)

Mitchell, C.R.; Geard, C.R.; Brenner, D.J.; Hande, P.; Azizova, T.V.; Burak, L.E.; Khokhryakov, V.F.; Vasienko, E.K.

2003-01-01

Multicolor banding fluorescence in situ hybridization (mBAND) was used to investigate the presence of stable intra-chromosomal aberrations in chromosomes 1, 2 and 5 in a population of individuals exposed previously to low and/or high-LET radiation. Peripheral blood lymphocytes were taken from healthy Russian nuclear workers occupationally exposed to plutonium α -particles, γ -rays or both at the Mayak complex from 1949 onwards. Metaphase spreads were produced and chromosomes hybridized with mBAND probes and scored for intra-chromosomal aberrations including inversions and deletions. A large difference between the intra-chromosomal aberration frequencies for the high-plutonium (∼1.1 Gy) and the high- γ exposed (∼1.5 Gy) individuals was observed in all three chromosomes studied (chromosome 1: 1.9 ± 0.5 % (n=7) vs. 0.1 ± 0.1% (n=5); chromosome 2: 1.7 ± 0.4% (n=7) vs. 0 [0 -0.3]% (n=6); chromosome 5: 3.7 ± 0.5 % (n=11) vs. 0.1 ± 0.1 % (n=11) (high-plutonium vs. high-γ exposure)). Controls (n=5) showed very few or no intra-chromosomal aberrations. Significantly fewer aberrations were observed in chromosomes 1 and 2 compared with chromosome 5, studied previously in this cohort, suggesting that intra-chromosomal changes involving chromosomes 1 and 2 may be more lethal to the cell than those involving chromosome 5. The dramatic differences in yields of intra-chromosomal aberrations in high-plutonium exposure relative to low may provide a means of discrimination to estimate both the dose and type of previous radiation exposure in populations

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

Stage specificity and dose-response relationships for chromosome aberrations induced in mouse primary spermatocytes following X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Matsuda, Y.; Tobari, I.; Utsugi, T.

1986-05-01

In this study, dose-response relationships were examined for chromosome aberrations observed at diakinesis-metaphase I of spermatocytes with X-irradiation at various stages of meiosis (diplotene, mid-pachytene, zygotene and leptotene). The frequencies of cells with X-ray-induced chromosome aberrations increased with dose at all stages in the applied range of 0.5-3.0 Gy and tended to increase as the irradiated stages descended after leptotene stage. In three stages, the frequencies increased exponentially with dose, but the rates of induction of chromosome breaks were markedly different depending on the stages at which spermatocytes were irradiated with X-rays. The rate of induction was the highest at diplotene and the lowest at leptotene, suggesting that diplotene spermatocytes had the highest radiosensitivity to the induction of chromosome breaks, followed by pachytene, zygotene and leptotene spermatocytes in that order. The dose-response relationships fitted well to linear equations for deletion-type aberrations at each stage, and to linear-quadratic equations for exchange-type aberrations at all stages except for leptotene. At leptotene, the chromatid exchanges were hardly observed, the aberrations being mainly consisted of iso-chromatid fragments. On the contrary, chromatid exchanges and iso-chromatide deletions were mainly observed at later stages (zygotene-diplotene).

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 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...

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.

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

Morphological images analysis and chromosomic aberrations classification based on fuzzy logic

International Nuclear Information System (INIS)

Souza, Leonardo Peres

2011-01-01

This work has implemented a methodology for automation of images analysis of chromosomes of human cells irradiated at IEA-R1 nuclear reactor (located at IPEN, Sao Paulo, Brazil), and therefore subject to morphological aberrations. This methodology intends to be a tool for helping cytogeneticists on identification, characterization and classification of chromosomal metaphasic analysis. The methodology development has included the creation of a software application based on artificial intelligence techniques using Fuzzy Logic combined with image processing techniques. The developed application was named CHRIMAN and is composed of modules that contain the methodological steps which are important requirements in order to achieve an automated analysis. The first step is the standardization of the bi-dimensional digital image acquisition procedure through coupling a simple digital camera to the ocular of the conventional metaphasic analysis microscope. Second step is related to the image treatment achieved through digital filters application; storing and organization of information obtained both from image content itself, and from selected extracted features, for further use on pattern recognition algorithms. The third step consists on characterizing, counting and classification of stored digital images and extracted features information. The accuracy in the recognition of chromosome images is 93.9%. This classification is based on classical standards obtained at Buckton [1973], and enables support to geneticist on chromosomic analysis procedure, decreasing analysis time, and creating conditions to include this method on a broader evaluation system on human cell damage due to ionizing radiation exposure. (author)

Manipulating chromosome structure and metaphase status with ultraviolet light and repair synthesis inhibitors

Energy Technology Data Exchange (ETDEWEB)

Mullinger, A.M.; Johnson, R.T. (Cambridge Univ. (UK). Dept. of Zoology)

1985-02-01

DNA repair occurs in metaphase-arrested cells in response to ultraviolet irradiation. In the presence of the repair synthesis inhibitors, hydroxyurea and 1-..beta..-D-arabinofuranosylcytosine, the chromosomes of such cells are decondensed. The dose response of chromosome decondensation varies between different cell types. In human cells defective in excision repair there is much less chromosome decondensation in response to the same ultraviolet dose and time of repair inhibition. However, a simian virus 40-transformed muntjac cell displays pronounced chromosome decondensation but has limited incision ability. Both chromosome decondensation and single-strand break accumulation in the presence of inhibitors are reversed when DNA precursors are provided, but reversal after higher ultraviolet doses and longer period of incubation leads to recondensed chromosomes that are fragmented. Although the chromosomes of repair-inhibited metaphase cells are decondensed in fixed preparations, their morphology appears normal in intact cells. The cells also retain a capacity to induce prematurely condensed chromosomes (PCC) when fused with interphase cells: compared with control mitotic cells, the speed of induction is sometimes reduced but the final amount of PCC produced is similar.

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

Evaluation of chromosome aberration frequency instable in individual groups residents at the municipality of Monte Alegre, Para, Brazil, exposed to radon

International Nuclear Information System (INIS)

Yunes, Samira Nogarol

2010-01-01

The municipality of Monte Alegre is a region that presents natural radiation high due to the presence of the radionuclide uranium ( 238 U) in its soil, which through its decay gives rise to element Rn, a gas. The radioactivity of the rocks has become a problem for the population of Monte Alegre, from the moment when the radioactive material began to be used in the construction of houses and paving of streets. Among all bio markers related to environmental exposures and its biological effects, the chromosomal aberrations are considered good bio markers as predictors of the risk of cancer. Studies suggest that the frequency of chromosomal aberrations may be related to the genetic instability individual and/or exposure to ionizing radiation. Our work aimed to evaluate the frequency of chromosomal aberrations in individuals in the region of high natural radioactivity in Monte Alegre-PA. As well as to correlate the cytogenetic analysis made in this study with the results of analysis of frequency of polymorphisms of genes of DNA repair carried out in another study that resulted in other dissertation. In accordance with the distribution of the data obtained in characterizing environmental radiological and in the calculation of dose, were chosen residents of homes with more and less exposure to radiation. The samples of peripheral blood of 85 individuals of the resident population of the region of Monte Alegre - PA were collected and examine provided two slides for individual was performed to verify the quality of the sample. Through this evaluation we decide that 33% of the material collected, or is, samples of 28 individuals were in suitable conditions for analysis of the frequency of chromosomal aberrations. After the collections lymphocytes present in the sample were cultivated in accordance with the methodology proposed for obtaining of cells in metaphase. were analyzed 6,177 metaphases of 28 individuals among which were found dicentric chromosomes 4 and 19 fragments

Biodosimetry for medical diagnostic X-ray workers using stable chromosome aberration

International Nuclear Information System (INIS)

Wang Zhiquan; Liu Xuping; Li Jin

1996-01-01

The stable chromosome aberrations of medical diagnostic X-ray workers were analyzed using G-banding and their accumulative doses were evaluated. The results showed that the frequencies of reciprocal translocation, stable aberration and total aberration among the 4417 metaphase spread from 44 cases of medical diagnostic X-ray workers were distinctly higher than control values (P<0.05∼0.005). The stable aberration predominated strikingly in total aberration and reciprocal translocation was 57% in the stable aberrations. The medical diagnostic X-ray workers were divided into 3 groups according to calendar year of entry. The data showed that the frequencies of total aberration, stable aberration and reciprocal translocation increased with working years, especially in two groups who started working before 1970, there are statistically significant differences between the calendar year of entry before 1960 and 1960∼1969 in X-ray workers and control group. According to the equation recommended by Straume, linear coefficient (α) in linear quadratic model recommended by Schmid and the transformation coefficient by Lucas, the accumulative doses calculated are 0.58, 0.37 and 0.07 Gy for calendar year of entry before 1960, 1960∼1969 and after 1970 in X-ray workers, respectively

Applying deep learning technology to automatically identify metaphase chromosomes using scanning microscopic images: an initial investigation

Science.gov (United States)

Qiu, Yuchen; Lu, Xianglan; Yan, Shiju; Tan, Maxine; Cheng, Samuel; Li, Shibo; Liu, Hong; Zheng, Bin

2016-03-01

Automated high throughput scanning microscopy is a fast developing screening technology used in cytogenetic laboratories for the diagnosis of leukemia or other genetic diseases. However, one of the major challenges of using this new technology is how to efficiently detect the analyzable metaphase chromosomes during the scanning process. The purpose of this investigation is to develop a computer aided detection (CAD) scheme based on deep learning technology, which can identify the metaphase chromosomes with high accuracy. The CAD scheme includes an eight layer neural network. The first six layers compose of an automatic feature extraction module, which has an architecture of three convolution-max-pooling layer pairs. The 1st, 2nd and 3rd pair contains 30, 20, 20 feature maps, respectively. The seventh and eighth layers compose of a multiple layer perception (MLP) based classifier, which is used to identify the analyzable metaphase chromosomes. The performance of new CAD scheme was assessed by receiver operation characteristic (ROC) method. A number of 150 regions of interest (ROIs) were selected to test the performance of our new CAD scheme. Each ROI contains either interphase cell or metaphase chromosomes. The results indicate that new scheme is able to achieve an area under the ROC curve (AUC) of 0.886+/-0.043. This investigation demonstrates that applying a deep learning technique may enable to significantly improve the accuracy of the metaphase chromosome detection using a scanning microscopic imaging technology in the future.

A high resolution chromosome image processor for study purposes, NIRS-1000:CHROMO STUDY, and algorithm developing to classify radiation induced aberrations.

Science.gov (United States)

Yamamoto, M; Hayata, I; Furuta, S

1992-03-01

Since 1989 we have promoted a project to develop an automated scoring system of radiation induced chromosome aberrations. As a first step, a high resolution image processing system for study purposes, NIRS-1000:CHROMO STUDY, has been developed. It is composed of: (1) CHROMO MARKER whose main purpose is to mark on images to make image data base, (2) CHROMO ALGO whose purpose is algorithm development, and (3) METAPHASE RANKER whose purposes are metaphase finding and ranking with a high power objective lens. However, METAPHASE RANKER is presently under development. The system utilizes a high definition video system so as to realize the best spatial resolution that is achievable with an optical microscope using an objective lens (x 100, numerical aperture 1.4). The video camera has 1024 effective scan lines to realize 0.1 microns sampling on a specimen. The system resolution achieved on the hard copy is less than 0.3 microns on a specimen. A preliminary algorithm has been developed to classify the aberrations on the system using projection information of gray level. The preliminary test results on excellent 10 metaphases show that the correct classification ratio is 92.7%, that the detection rate of the aberrations is 83.3% and that the false positive rate is 6.1%.

''Protective'' effect of cells gamma-irradiation at the metaphase of mitosis after UV-irradiation at the S-period

Energy Technology Data Exchange (ETDEWEB)

Lebedeva, L I; Chubykin, V L [AN SSSR, Novosibirsk. Inst. Tsitologii i Genetiki

1975-10-01

As a result of the ultraviolet irradiation in vitro of the embryo fibroblasts of BALB mice in the S-stage with an incident dose of 40 erg/mm/sup 2/, 20.1% cells showed chromosome aberrations. Additional gamma irradiation of cells in the metaphase of the first mitosis with a dose of 5 krad leads with a high degree of certainty to a decrease to 11.7% in the frequency of aberrant cells observed in the same mitotic stage. The frequency of spontaneous aberrations does not change during the first few minutes after the gamma irradiation of intact cells. The ''protective'' effect of gamma rays cannot be attributed to non-uniform changes in the duration of the mitotic stages for aberrant and normal cells, to the adhesion of chromosome fragments or to the breaking of bridges in the anaphase. The destruction of cells during irradiation is also an unlikely explanation of the observed effect. It is assumed that the decrease in the frequency of aberrations is a result of the previously predicted modification of the processes involved, when potential chromosome damage becomes visible abberations during metaphase.

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)

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

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)

Test for Chemical Induction of Chromosome Aberration in Cultured Chinese Hamster Ovary (CHO) Cells With and Without Metabolic Activation. Test Article: N,N,N’,N’-tetramethyl Ethanediamine (TMEDA)

Science.gov (United States)

2008-06-13

the RCG and/or RMI: ill addition, the percentage of polyploid and endoreduplicated cells was also determined at each concentration. Both the solvent...percentage of polyploid and endoreduplicated cells was also determined at each concentration. The types of chromosome aberrations scored and the...not decipherable. Considered as a single aberration. Severely damaged cell - cell with 10 or more aberrations. Polyploid cells - metaphases with

Multiple chromosome aberrations among newborns from high level natural radiation area and normal level natural radiation area of south west coast of Kerala

International Nuclear Information System (INIS)

Soren, D.C.; Ramachandran, E.N.; Karuppasamy, C.V.; Cheriyan, V.D.; Anil Kumar, V.; Koya, P.K.M.; Seshadri, M.

2010-01-01

Cord blood samples were collected in heparin vials and microculture techniques employed to obtain good metaphase chromosome spreads. In cytogenetic studies on newborns cells with multiple aberrations were recorded in 57 from a total of 27285 newborns (1266972 cells). Of these 17294 newborns (964140 cells) were from High Level Natural Radiation Area (HLNRA) and 9991 newborns (302832 cells) from Normal Level Natural Radiation Area (NLNRA). Cells with multiple aberrations were observed in 38 and 19 newborns from High and Normal Level Natural Radiation Area respectively. On an average one cell with multiple aberrations was observed among 479 newborns. Cells with multiple aberrations were observed in newborns from HLNRA as well as NLNRA in both males and females. Gender difference of newborns, maternal age group and background radiation levels did not seem to have any influence in the occurrence of Multiple chromosome aberrations

Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

Science.gov (United States)

Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

2013-07-08

The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat.

Chromosome breakage in Vicia faba by ozone

Energy Technology Data Exchange (ETDEWEB)

Fetner, R H

1958-02-15

Meristem cells of Vicia faba roots were exposed to an atmosphere of ozone and the fraction of cells showing chromosome aberrations were recorded. Chromosome aberrations were observed on a dose-response basis after exposing the seeds to 0.4 wt. percent ozone for 15, 30, and 60 minutes. The results of ozone, x-rays, and ozone and x-ray treatments are presented. A small number of root tips from each group was treated with colchicine and an analysis made of metaphase aberrations. These observations confirmed that the aberrations were all of the chromosome-type.

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

Chromosomal aberrations in chronic lymphocytic leukemia detected by conventional cytogenetics with DSP30 as a single agent: comparison with FISH.

Science.gov (United States)

Kotkowska, Aleksandra; Wawrzyniak, Ewa; Blonski, Jerzy Z; Robak, Tadeusz; Korycka-Wolowiec, Anna

2011-08-01

The aim of our study was to estimate the usefulness for conventional cytogenetics (CC) of DSP30 as a single agent (CC-DSP30) for detecting the most important chromosomal aberrations revealed in CLL by FISH and to find other abnormalities possibly existing but undetected by FISH with standard probes. Using CC-DSP30, the metaphases suitable for analysis were obtained in 90% of patients. CC-DSP30 and FISH were similarly efficacious for detecting del(11)(q22) and trisomy 12, whereas FISH was more sensitive for del(13)(q14). Sole del(13)(q14) detected by FISH, in 50% of patients was associated with other aberrations revealed by CC-DSP30. Additionally, the most recurrent anomaly detected by CC-DSP30 were structural aberrations of chromosome 2. Copyright © 2011 Elsevier Ltd. All rights reserved.

Accurate cytogenetic biodosimetry through automated dicentric chromosome curation and metaphase cell selection [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Jin Liu

2017-08-01

Full Text Available Accurate digital image analysis of abnormal microscopic structures relies on high quality images and on minimizing the rates of false positive (FP and negative objects in images. Cytogenetic biodosimetry detects dicentric chromosomes (DCs that arise from exposure to ionizing radiation, and determines radiation dose received based on DC frequency. Improvements in automated DC recognition increase the accuracy of dose estimates by reclassifying FP DCs as monocentric chromosomes or chromosome fragments. We also present image segmentation methods to rank high quality digital metaphase images and eliminate suboptimal metaphase cells. A set of chromosome morphology segmentation methods selectively filtered out FP DCs arising primarily from sister chromatid separation, chromosome fragmentation, and cellular debris. This reduced FPs by an average of 55% and was highly specific to these abnormal structures (≥97.7% in three samples. Additional filters selectively removed images with incomplete, highly overlapped, or missing metaphase cells, or with poor overall chromosome morphologies that increased FP rates. Image selection is optimized and FP DCs are minimized by combining multiple feature based segmentation filters and a novel image sorting procedure based on the known distribution of chromosome lengths. Applying the same image segmentation filtering procedures to both calibration and test samples reduced the average dose estimation error from 0.4 Gy to <0.2 Gy, obviating the need to first manually review these images. This reliable and scalable solution enables batch processing for multiple samples of unknown dose, and meets current requirements for triage radiation biodosimetry of high quality metaphase cell preparations.

Chromosome aberrations in human peripheral lymphocytes induced by single or fractionated X-irradiation

International Nuclear Information System (INIS)

Ivanov, B.; Leonard, A.; Deknyudt, G.

1980-01-01

Investigated is the effect of single (125 and 250 R) and fractionated (2x125 R) irradiation on the output of chromosome aberrations in lymphocytes of human peripheral blood kept between irradiations at the temperature of 5 deg C. The single irradiation is carried out immediately after vein-puncture. In the case of fractionated irradiation the first dose of 125R is given after vein-puncture, the second, in the interval of 2, 8 and 24 hours. Blood is cultivated immediately after two irradiations in order to prepare metaphase plates for cytogenic analysis. Repair processes in cell heritage structures are not realised in blood irradiated by fractions which is kept at 5 deg C between irradiations. On the contrary, chromosome fragments, interstitial deletions, aberrant cells and cell breaks are found in a large amount in blood irradiated by fractions. They have appeared with the authentically high statistic difference as compared with the cells irradiated one time with the same dose. This effect is probably attained due to blood preservation

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

Energy Technology Data Exchange (ETDEWEB)

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)

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)

Induction of chromosomal aberrations in human primary fibroblasts and immortalized cancer cells exposed to extremely-low-frequency electromagnetic fields

International Nuclear Information System (INIS)

Seyyedi, S. S.; Mozdarani, H.; Rezaei Tavirani, M.; Heydari, S.

2010-01-01

Rapidly increasing possibilities of exposure to environmental extremely low-frequency electromagnetic fields have become a topic of worldwide investigation. Epidemiological and laboratory studies suggest that exposure to extremely low-frequency electromagnetic fields may increase cancer risk therefore assessment of chromosomal damage in various cell lines might be of predictive value for future risk estimation. Materials and Methods: Primary cultures of fibroblasts from human skin biopsy were exposed to continuous extremely low-frequency electromagnetic fields (3, 50 and 60 Hz, sinusoidal, 3h, and 4 m T). Also immortalized cell lines, SW480, MCF-7 and 1321N1 were exposed to continuous extremely low-frequency electromagnetic fields (50 Hz, sinusoidal, 3 h, 4 m T). Metaphase plates Were prepared according to standard methods and stained in 5% Giemsa solution. Chromosomal aberrations of both chromosome and chromatid types were scored to evaluate the effects of extremely low-frequency electromagnetic fields on primary or established cell lines. Results: Results indicate that by increasing the frequency of extremely low-frequency electromagnetic fields, chromosomal aberrations were increased up to 7-fold above background levels in primary human fibroblast cells. In addition, continuous exposure to a 50 Hz electromagnetic field led to a significant increase in chromosomal aberrations in SW480, MCF-7 and 1321N1 cell lines compared to sham control. Conclusion: Results obtained indicate that extremely low-frequency electromagnetic fields has the potential for induction of chromosomal aberrations in all cell types.

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.)

Automated detection of analyzable metaphase chromosome cells depicted on scanned digital microscopic images

Science.gov (United States)

Qiu, Yuchen; Wang, Xingwei; Chen, Xiaodong; Li, Yuhua; Liu, Hong; Li, Shibo; Zheng, Bin

2010-02-01

Visually searching for analyzable metaphase chromosome cells under microscopes is quite time-consuming and difficult. To improve detection efficiency, consistency, and diagnostic accuracy, an automated microscopic image scanning system was developed and tested to directly acquire digital images with sufficient spatial resolution for clinical diagnosis. A computer-aided detection (CAD) scheme was also developed and integrated into the image scanning system to search for and detect the regions of interest (ROI) that contain analyzable metaphase chromosome cells in the large volume of scanned images acquired from one specimen. Thus, the cytogeneticists only need to observe and interpret the limited number of ROIs. In this study, the high-resolution microscopic image scanning and CAD performance was investigated and evaluated using nine sets of images scanned from either bone marrow (three) or blood (six) specimens for diagnosis of leukemia. The automated CAD-selection results were compared with the visual selection. In the experiment, the cytogeneticists first visually searched for the analyzable metaphase chromosome cells from specimens under microscopes. The specimens were also automated scanned and followed by applying the CAD scheme to detect and save ROIs containing analyzable cells while deleting the others. The automated selected ROIs were then examined by a panel of three cytogeneticists. From the scanned images, CAD selected more analyzable cells than initially visual examinations of the cytogeneticists in both blood and bone marrow specimens. In general, CAD had higher performance in analyzing blood specimens. Even in three bone marrow specimens, CAD selected 50, 22, 9 ROIs, respectively. Except matching with the initially visual selection of 9, 7, and 5 analyzable cells in these three specimens, the cytogeneticists also selected 41, 15 and 4 new analyzable cells, which were missed in initially visual searching. This experiment showed the feasibility of

Automatic aberration scoring using whole chromosome F.I.S.H

International Nuclear Information System (INIS)

Piper, J.; Bayley, R.; Boyle, S.; Fantes, J.A.; Green, D.K.; Gordon, J.; Hill, W.; Ji, L.; Malloy, P.; Perry, P.; Rutovitz, D.; Stark, M.; Whale, D.

1993-01-01

A radiation-induced rearrangement involving a painted and a non-painted chromosome will usually result in two partly-painted chromosomes, typically either a dicentric chromosome and associated fragment, or a reciprocal translocation pair. A consequence of such a rearrangement is that the number of painted image regions in the metaphase is increased by one, and their size distribution is altered. More complex rearrangements are uncommon, particularly at low doses. A high proportion of damaged cells can therefore be registered simply by detecting when the distribution of painted components differs from the expected number and size. A system has been constructed to pre-screen for damaged cells. It comprises automatic fluorescence metaphase finding followed by relocation and digitization of probe and counterstain channels at high resolution. Fully automatic segmentation in counterstain discriminates chromosomes from interphase nuclei and determines whether a metaphase is approximately diploid. The painted regions are segmented and their relative sizes estimated. Rules are applied which reduce the false positives due to artifacts such as overlapped painted chromosomes. More than 70% of cells with radiation damage involving painted and unpainted chromosomes were detected in a preliminary experiment using a small data set, with a low false positive rate. Results from a larger experiment in progress are presented

Studies on chromosomal aberrations and dominant lethal mutations induced by x irradiation in germ cells of male mice

International Nuclear Information System (INIS)

Wang Xianli; Wang Mingdong; Wang Bin; Sun Shuqing

1992-01-01

After male mice irradiated by 2 Gy X rays mated to normal virginal females superovulated with PMSG and HCG, pronuclei chromosome spreading of first-cleavage embryos were prepared and chromosomal aberrations of paternal pronuclei were observed. The results showed that the frequency of chromosomal aberrations was highest irradiated at spermatic stage among different stages of spermatogenesis. The sequence of radiosensitivity in spermatogenesis was as follows: spermatids > mature sperm > spermatocyte > spermatogonia and stem spermatogonia. The frequencies of paternal chromosomal aberrations resulted from irradiation at spermatids and mature sperms were significantly higher than that in control. The reciprocal translocations of stem spermatogonia induced by 2 Gy X rays in those male mice were also examined in the preparations of diakinesis-metaphase I. The frequency of reciprocal translocations were 0.0429 per cell and significantly higher than that in control. The proportion of unbalanced gametes, resulting in lethal embryos after fertilization, was 0.02145 to be predicted. At the same time, the dominant lethality induced by X rays in stem spermatogonia was measured, being 0.0371. The frequency of dead fetuses in irradiation group was about twice as in control. The regression analysis was found that the reciprocal translocations was markedly related to the dominant lethality

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.)

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)

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

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.

Chromosome aberrations in workers of ignalina nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Griciene, B.; Januskeviciute, I.; Mierauskiene, J.; Slapsyte, G. [Vilnius Univ. (Lithuania)

2006-07-01

Full text of publication follows: The Ignalina Nuclear Power Plant (I.N.P.P.) workers and outside workers including visitors constitute the largest occupational group exposed to low doses of ionizing radiation in Lithuania. In 2004, the annual collective dose to these workers (4392 persons) was 6,83 man Sv. The maximum annual individual dose of I.N.P.P. workers was 19,16 mSv, and of outside workers was 29,41 mSv. However, according to calculations performed by the Lithuanian Radiation Protection Centre, the decommissioning of I.N.P.P. (the I.N.P.P. is to be shut down by 2009) will result in collective dose of 35 man Sv. Therefore, a special attention should be given to implementation of radiation protection programme. The importance of cytogenetic studies in the medical surveillance of radiation-exposed persons is generally acknowledged. The aim of the present study was to analyse chromosome aberration frequencies in lymphocytes of I.N.P.P. workers. The blood sampling of 27 male workers was performed in October 2004, after planned outage of I.N.P.P.. It was estimated that outages of I.N.P.P. Units contributed 84% to all annual occupational collective dose. Average cumulative dose of 18 workers was 290,7 mSv (group A), and of 9 workers - 71,7 mSv (group B). The mean annual doses averaged over the three-year-period were 15,2 mSv and 0,76 mSv, respectively. None of the exposed workers had ever exceeded the permissible dose limit. The average age of group A workers was 45,2 years, and group B 48,2 years. A questionnaire form with details on age, occupational history, smoking habit and alcohol intake, medication, history of recent illness was completed for each person at the time of blood collection. 64 non-exposed male donors approximately matched by age were used as controls (group C). Heparinized venous blood samples were taken and cultures were initiated within 24 h according to the standard procedures. At least 500 first cycle metaphases were analysed from each

Chromosome aberrations in workers of ignalina nuclear power plant

International Nuclear Information System (INIS)

Griciene, B.; Januskeviciute, I.; Mierauskiene, J.; Slapsyte, G.

2006-01-01

Full text of publication follows: The Ignalina Nuclear Power Plant (I.N.P.P.) workers and outside workers including visitors constitute the largest occupational group exposed to low doses of ionizing radiation in Lithuania. In 2004, the annual collective dose to these workers (4392 persons) was 6,83 man Sv. The maximum annual individual dose of I.N.P.P. workers was 19,16 mSv, and of outside workers was 29,41 mSv. However, according to calculations performed by the Lithuanian Radiation Protection Centre, the decommissioning of I.N.P.P. (the I.N.P.P. is to be shut down by 2009) will result in collective dose of 35 man Sv. Therefore, a special attention should be given to implementation of radiation protection programme. The importance of cytogenetic studies in the medical surveillance of radiation-exposed persons is generally acknowledged. The aim of the present study was to analyse chromosome aberration frequencies in lymphocytes of I.N.P.P. workers. The blood sampling of 27 male workers was performed in October 2004, after planned outage of I.N.P.P.. It was estimated that outages of I.N.P.P. Units contributed 84% to all annual occupational collective dose. Average cumulative dose of 18 workers was 290,7 mSv (group A), and of 9 workers - 71,7 mSv (group B). The mean annual doses averaged over the three-year-period were 15,2 mSv and 0,76 mSv, respectively. None of the exposed workers had ever exceeded the permissible dose limit. The average age of group A workers was 45,2 years, and group B 48,2 years. A questionnaire form with details on age, occupational history, smoking habit and alcohol intake, medication, history of recent illness was completed for each person at the time of blood collection. 64 non-exposed male donors approximately matched by age were used as controls (group C). Heparinized venous blood samples were taken and cultures were initiated within 24 h according to the standard procedures. At least 500 first cycle metaphases were analysed from each

Epidemiological study using the chromosome aberration technique in different population samples

International Nuclear Information System (INIS)

Jesus Prieto, M.; Moreno, M.; Olivares, P.; Gomez, M.; Herranz, R.

1997-01-01

As far back as 10 years ago, the Gregorio Maranon General University Hospital (HGUGM) was equipped with a laboratory of biological dosimetry and has undertaken dosimetric estimations of individuals suspected with overexposure to ionizing radiation. For this purpose it was necessary to carry out studies on the basic frequency of chromosomal aberrations in a controlled (radiation exposed) population. A study was conducted on 72 individuals of the community of Madrid who had not been exposed to ionizing radiation. 500 metaphases per individual were examined and a basic frequency of 0.7 (dic)/1000 cells analysed. Parameters such as age, gender and cigarette consumption were considered and results show a linear dependency with age and consumption of cigarettes, but not with gender

Metaphase chromosome and nucleoid differences between CHO-K1 and its radiosensitive derivative xrs-5

International Nuclear Information System (INIS)

Schwartz, J.L.; Stephens, J.; Vaughan, A.T.M.

1992-05-01

The Chinese hamster ovary (CHO) cell line xrs-5 is a radiation-sensitive mutant isolated from CHO-K1 cells. The radiation sensitivity is associated with a defect in DNA double-strand break rejoining. Chromatin structure also appears altered in xrs-5 cells compared to the parental CHO-K1 cells. Metaphase chromosomes from xrs-5 are more condensed in appearance than CHO-K1 chromosomes. The overcondensed look is not the result of colcemid sensitivity. Electron microscopy studies suggest that xrs-5 metaphase chromosomes have larger loops of chromatin extending out from the chromosome core. There are also differences between CHO-K1 and xrs-5 cells in the size and fluorescence pattern of ethidium bromide-stained nucleoid preparations. These results suggest that there is a fundamental difference between CHO-K1 and xrs-5 in either the organization of the supercoiled loops of DNA attached to the nuclear matrix or in the nature of the proteins that attach the DNA to the matrix. These alterations in chromosome structure may underlie, in part, the radiation sensitivity of xrs-5 cells

Metaphase chromosome and nucleoid differences between CHO-K1 and its radiosensitive derivative xrs-5

International Nuclear Information System (INIS)

Schwartz, J.L.; Stephens, J.; Vaughan, A.T.M.

1993-01-01

The Chinese hamster ovary (CHO) cell line xrs-5 is a radiation-sensitive mutant isolated from CHO-K1 cells. The radiosensitivity is associated with a defect in DNA double-strand break rejoining. Chromatin structure also appears altered in xrs-5 cells compared with the parental CHO-K1 cells. Metaphase chromosomes form xrs-5 are more condensed in appearance than CHO-K1 chromosomes. The overcondensed look is not the result of colcemid sensitivity. Electron microscopy studies suggest that xrs-5 metaphase chromosomes have larger loops of chromatin extending out from the chromosome core. There are also differences between CHO-K1 and xrs-5 cells in the size and fluorescence pattern of ethidium bromide-stained nucleoid preparations. These results suggest that there is a fundamental difference between CHO-K1 and xrs-5 in either the organization of the supercoiled loops of DNA attached to the nuclear matrix or in the nature of the proteins that attach the DNA to the matrix. These alterations in chromosome structure may underlie, in part the radiation sensitivity of xrs-5 cells. (Author)

Preimplantation diagnosis of repeated miscarriage due to chromosomal translocations using metaphase chromosomes of a blastomere biopsied from 4- to 6-cell-stage embryos.

Science.gov (United States)

Tanaka, Atsushi; Nagayoshi, Motoi; Awata, Shoichiro; Mawatari, Yoshifumi; Tanaka, Izumi; Kusunoki, Hiroshi

2004-01-01

To evaluate the safety and accuracy of karyotyping the blastomere chromosomes at metaphase in the natural cell cycle for preimplantation diagnosis. A pilot study. A private infertility clinic and a university laboratory. Eleven patients undergoing IVF and preimplantation diagnosis. Intact human embryos at the 4- to 6-cell stage and human-mouse heterokaryons were cultured and checked hourly for disappearance of the nuclear envelope. After it disappeared, the metaphase chromosomes were analyzed by fluorescence in situ hybridization. Percentage of analyzable metaphase plates and safety and accuracy of the method. The success rate of electrofusion to form human-mouse heterokaryons was 87.1% (27/31), and analyzable chromosomes were obtained from 77.4% (24/31) of the heterokaryons. On the other hand, disappearance of the nuclear envelope occurred in 89.5% (17/19) of the human embryos and it began earlier than that in the heterokaryons. Analyzable chromosomes were obtained and their translocation sites were identified in all blastomeres biopsied from the 17 embryos. After the biopsy, 67.0% of the embryos could develop to the blastocyst stage. The natural cell cycle method reported herein requires frequent observation, but it is safe, with no artificial effects on the chromosomes and without loss of or damage to blastomeres, which occurred with the electrofusion method. Using the natural cell cycle method, we could perform preimplantation diagnosis with nearly 100% accuracy.

Chromosome aberrations in peripheral blood lymphocytes in subjects occupationally exposed to ionizing radiation or chemical clastogens

International Nuclear Information System (INIS)

Lalic, H.; Radosevic-Stasic, B.

2002-01-01

To get an insight into genotoxic risk in some occupations, in this study the chromosome aberration analysis of peripheral blood lymphocytes was made in 20 physicians and nurses exposed to a low dose of ionizing radiation in a hospital, 12 individuals working with X-rays in a cement factory and 19 technicians working with some chemical toxic agents in the laboratories of a medical school. The control group consisted of 14 sex- and age-matched unexposed persons living in the same district area. The data showed that the total number of chromosome aberrations in 200 scored metaphases in all examined groups were almost the same and inside the low-permitted values. In hospital workers, however, the percentage of acentric and dicentric fragments (1.63 ± 0.28 vs 0.31 ± 0.21 and 0.47 ± 0.18 vs 0.0, respectively) increased predominantly in contrast to cement-factory employees and laboratory workers, where a higher incidence of minutes (0.58 ± 0.19 vs 0.31 ± 0.2) or gaps (2.21 ± 0.37 vs 1.15 ± 1.15) was noticed. Moreover, in groups exposed to low doses of ionizing radiation (hospital and factory), a positive correlation was found between the total number of chromosome aberrations and the 6-year absorption dose or working period, suggesting an effect of cumulative dosage. (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...

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)

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)

Radiation-induced chromosome aberrations in the rat peripheral blood

International Nuclear Information System (INIS)

Ziemba-Zoltowska, B.; Bocian, E.; Radwan, I.; Rosiek, O.; Sablinski, J.

1978-01-01

Chromosome aberrations in rat lymphocytes of peripheral blood after X (in vitro and in vivo) and 3 H tritiated water (in vivo) irradiations were studied. The yield of chromosome aberrations after in vivo and in vitro exposure to X-rays was similar. The frequency of chromosome aberrations three weeks after exposure to X-rays and soon after irradiation was practically on the same level. The yield of chromosome aberrations determined three weeks after injection with tritiated water or X-rays exposure was similar. (author)

Chromosomal aberrations in bone marrow of continuously irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Chlebosky, O; Praslicka, M; Chlebovska, K [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Prirodovedecka Fakulta

1975-01-01

Research on chromosomal aberrations of the bone marrow in continuously irradiated rats showed that chromosomal aberrations are a highly sensitive indicator of radiation injury. An increase in the chromosomal aberration frequency was already found on the 5th day at daily doses of 0.5 R, i.e. a 12% increase at a total dose of 25 R. In the steady-state stage at daily doses of 0.5; 1; 2.5 R, the number of chromosomal aberrations stabilized at values of about 20%; at daily doses of 5 and 10 R at values of 30.=., at daily doses of 53 R at 45%, at a daily dose of 82.5 R, the number of chromosomal aberrations increased to 55%.

Distinction of metaphases in the first cell cycle for automated system in radiation dosimetry

International Nuclear Information System (INIS)

Hayata, I.; Kajima, J.; Okabe, N.

1992-01-01

As part of the biological improvements for developing an automated scoring system of radiation induced chromosome aberrations for radiation dosimetry, we introduce a new method for identifying the metaphases in the first cell cycle. Differing from the conventional method with BrdUrd, it focuses on the difference of chromosome number to be induced by inhibiting the cytokinesis with Cytochalasin B. Majority of the cells with 46 chromosomes were in the first cell cycle, and the ratio of those with 46 chromosomes in the second division was less than one per cent both when Cytochalasin B of 1.5 μg/ml was added to the culture of irradiated lymphocytes and when that of 1.8 μg/ml was added to that of non-irradiated cells for one day, respectively. The ratio of metaphases with over-condensed chromosomes is reduced, the clear-cut image of chromosomes is obtained, culture and staining processes are simpler, and the device of UV irradiation is not necessary. Thus the present Cytochalasin B method offers more qualified input, data based on the numerical difference, than conventional image based recognition, and upgrades the quality of the scoring in the automated analysis system. (Author)

Chromatin structure and ionizing-radiation-induced chromosome aberrations

International Nuclear Information System (INIS)

Muehlmann-Diaz, M.C.

1993-01-01

The possible influence of chromatic structure or activity on chromosomal radiosensitivity was studied. A cell line was isolated which contained some 10 5 copies of an amplified plasmid in a single large mosquito artificial chromosome (MAC). This chromosome was hypersensitive to DNase I. Its radiosensitivity was some three fold greater than normal mosquito chromosomes in the same cell. In cultured human cells irradiated during G 0 , the initial breakage frequency in chromosome 4, 19 and the euchromatic and heterochromatic portions of the Y chromosome were measured over a wide range of doses by inducing Premature Chromosome Condensation (PCC) immediately after irradiation with Cs-137 gamma rays. No evidence was seen that Y heterochromatin or large fragments of it remained unbroken. The only significant deviation from the expected initial breakage frequency per Gy per unit length of chromosome was that observed for the euchromatic portion of the Y chromosome, with breakage nearly twice that expected. The development of aberrations involving X and Y chromosomes at the first mitosis after irradation was also studied. Normal female cells sustained about twice the frequency of aberrations involving X chromosomes for a dose of 7.3 Gy than the corresponding male cells. Fibroblasts from individuals with supernumerary X chromosomes did not show any further increase in X aberrations for this dos. The frequency of aberrations involving the heterochromatic portion of the long arm of the Y chromosome was about what would be expected for a similar length of autosome, but the euchromatic portion of the Y was about 3 times more radiosensitive per unit length. 5-Azacytidine treatment of cultured human female fibroblasts or fibroblasts from a 49,XXXXY individual, reduced the methylation of cytosine residues in DNA, and resulted in an increased chromosomal radiosensitivity in general, but it did not increase the frequency of aberrations involving the X chromosomes

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

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)

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.

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

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)

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.)

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)

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

Techniques for imaging human metaphase chromosomes in liquid conditions by atomic force microscopy

Energy Technology Data Exchange (ETDEWEB)

Ushiki, Tatsuo; Hoshi, Osamu [Division of Microscopic Anatomy and Bio-imaging, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata 951-8510 (Japan); Shigeno, Masatsugu [SII NanoTechnology Incorporated, RBM Tsukiji Building, Shintomi 2-15-5, Chuo-ku, Tokyo 104-0041 (Japan)], E-mail: t-ushiki@med.niigata-u.ac.jp

2008-09-24

The purpose of this study was to obtain three-dimensional images of wet chromosomes by atomic force microscopy (AFM) in liquid conditions. Human metaphase chromosomes-obtained either by chromosome spreads or by an isolation technique-were observed in a dynamic mode by AFM in a buffer solution. Under suitable operating conditions with a soft triangular cantilever (with the spring constant of 0.08-0.4 N m{sup -1}), clear images of fixed chromosomes in the chromosome spread were obtained by AFM. For imaging isolated chromosomes with the height of more than 400 nm, a cantilever with a high aspect ratio probing tip was required. The combination of a Q-control system and the sampling intelligent scan (SIS) system in dynamic force mode AFM was useful for obtaining high-quality images of the isolated chromosomes, in which globular or cord-like structures about 50 nm thick were clearly observed on the surface of each chromatid.

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

Chromosomal analysis in mouse eggs fertilized in vitro with sperm exposed to ultraviolet light (UV) and methyl and ethyl methanesulfonate (MMS and EMS)

International Nuclear Information System (INIS)

Matsuda, Y.; Tobari, I.

1988-01-01

Chromosome aberrations were analyzed at the first-cleavage metaphase of mouse eggs fertilized in vitro with sperm exposed to ultraviolet light (UV) as well as to methyl and ethyl methanesulfonate (MMS and EMS). The frequencies of chromosome aberrations markedly increased with dose of UV as well as with concentration of MMS and EMS. In the UV-irradiation group, the frequency of chromosome-type aberrations was much higher than that of chromatid-type aberrations. About 90% of chromosome aberrations observed in the eggs following MMS and EMS treatment to sperm were chromosome type in which the frequency of chromosome fragments was the highest. The effects of UV on the induction of chromosome aberrations were clearly potentiated by post-treatment incubation of fertilized eggs in the presence of Ara-C or caffeine, but the effects of MMS and EMS were not pronounced by post-treatment of Ara-C or caffeine. The results indicate a possibility that UV damage induced in mouse sperm DNA is reparable in the eggs during the period between the entry of sperm into the egg cytoplasm and the first-cleavage metaphase. 35 refs.; 5 figs.; 4 tabs

Cytogenetic and genetic studies of radiation-induced chromosome damage in mouse oocytes. Part 1. Numerical and structural chromosome anomalies in metaphase II oocytes, pre- and post-implantation embryos

International Nuclear Information System (INIS)

Tease, Charles; Fisher, Graham

1996-01-01

The incidences of X-ray induced numerical and structural chromosome anomalies were screened in a range of developmental stages from metaphase II oocytes through to post-implantation embryos. Following 1 Gy of acute X-rays to immediately preovulatory stage oocytes, the rate of hyperploidy (chromosome gain) was found to be elevated over levels in unirradiated controls, at metaphase II, in 1-cell and 3.5 day pre-implantation embryos but not in 8.5 day post-implantation foetuses. In the latter, however, the frequency of mosaicism was significantly increased. A similar response of an increase in mosaicism but not in hyperploidy in 8.5 day post-implantation embryos was also found after irradiation of dictyate stage oocytes with 4 Gy of acute X-rays. Significantly elevated frequencies of structural chromosome anomalies were present in metaphase II oocytes and pre-implantation embryonic stages, but could not be detected in block-stained chromosome preparations from 8.5 day post-implantation foetuses. However, analysis of chromosome preparations after G-banding showed that almost 14% of 14.5 day foetuses carried a chromosome rearrangement after 1 Gy of X-rays to immediately preovulatory stage oocytes. Overall, our data indicate that the presence of radiation-induced chromosome gains are incompatible with embryonic survival but that a proportion of embryos with structural chromosome damage develop past mid-gestation. These latter embryos are therefore potentially capable of contributing to the genetic burden of the next generation

Detection of short repeated genomic sequences on metaphase chromosomes using padlock probes and target primed rolling circle DNA synthesis

Directory of Open Access Journals (Sweden)

Stougaard Magnus

2007-11-01

Full Text Available Abstract Background In situ detection of short sequence elements in genomic DNA requires short probes with high molecular resolution and powerful specific signal amplification. Padlock probes can differentiate single base variations. Ligated padlock probes can be amplified in situ by rolling circle DNA synthesis and detected by fluorescence microscopy, thus enhancing PRINS type reactions, where localized DNA synthesis reports on the position of hybridization targets, to potentially reveal the binding of single oligonucleotide-size probe molecules. Such a system has been presented for the detection of mitochondrial DNA in fixed cells, whereas attempts to apply rolling circle detection to metaphase chromosomes have previously failed, according to the literature. Methods Synchronized cultured cells were fixed with methanol/acetic acid to prepare chromosome spreads in teflon-coated diagnostic well-slides. Apart from the slide format and the chromosome spreading everything was done essentially according to standard protocols. Hybridization targets were detected in situ with padlock probes, which were ligated and amplified using target primed rolling circle DNA synthesis, and detected by fluorescence labeling. Results An optimized protocol for the spreading of condensed metaphase chromosomes in teflon-coated diagnostic well-slides was developed. Applying this protocol we generated specimens for target primed rolling circle DNA synthesis of padlock probes recognizing a 40 nucleotide sequence in the male specific repetitive satellite I sequence (DYZ1 on the Y-chromosome and a 32 nucleotide sequence in the repetitive kringle IV domain in the apolipoprotein(a gene positioned on the long arm of chromosome 6. These targets were detected with good efficiency, but the efficiency on other target sites was unsatisfactory. Conclusion Our aim was to test the applicability of the method used on mitochondrial DNA to the analysis of nuclear genomes, in particular as

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

Fluorescence in situ hybridization on human metaphase chromosomes detected by near-field scanning optical microscopy

NARCIS (Netherlands)

Moers, M.H.P.; Moers, M.H.P.; Kalle, W.H.J.; Kalle, W.H.J.; Ruiter, A.G.T.; Wiegant, J.C.A.G.; Raap, A.K.; Greve, Jan; de Grooth, B.G.; van Hulst, N.F.

1996-01-01

Fluorescence in situ hybridization o­n human metaphase chromosomes is detected by near-field scanning optical microscopy. This combination of cytochemical and scanning probe techniques enables the localization and identification of several fluorescently labelled genomic DNA fragments o­n a single

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)

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)

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

Biological dosimetry of absorbed radiation by C-banding of interphase chromosomes in peripheral blood lymphocytes

International Nuclear Information System (INIS)

Pantelias, G.E.

1993-01-01

In the present report a C-banding procedure, refined to avoid swelling and chromosome distortion of freshly prepared prematurely condensed chromosomes (PCCs) spreads, is used to identify aberrations in non-stimulated human lymphocytes. The method allows immediate banding of the centromeric regions and enables scoring of aberrations within a time interval (3-4h after blood sample withdrawal) that is only a fraction of that normally required when cells stimulated to proliferate are analysed at metaphase. The dose-response for dicentrics and centric rings measured in interphase lymphocytes was found to be similar to that obtained at metaphase. Measurement of dicentrics and centric rings in prematurely condensed chromosomes of human lymphocytes would provide valuable information on radiation dose estimates, especially in cases of extreme urgency. (Author)

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

Energy Technology Data Exchange (ETDEWEB)

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 aberration assays in barley (Hordeum vulgare)

Energy Technology Data Exchange (ETDEWEB)

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.

Comparative cytogenetic analysis of chromosomal aberrations and premature centromere division in persons exposed to radionuclides

International Nuclear Information System (INIS)

Jovicic, D.; Rakic, B.; Vukov, T.; Pajic, J.; Milacic, S.; Kovacevic, R.; Stevanovic, M.; Drakulic, D.; Bukvic, N.

2009-01-01

The aim of the research was to determine the presence of correlation between the frequency of premature centromere division (PCD) and chromosomal aberrations (CA) in metaphases in persons professionally exposed to radionuclides. Biological dosimetry was performed by conventional cytogenetic technique. The presence of PCD was confirmed by Fluorescent in situ hybridization (FISH). The L1.84 probe (specific for centromeric region of chromosome 18) was used. The analysis included 50 subjects employed in the Clinical Center of Serbia (C) (the average age of 45.24 ± 1.18 and the average exposition time 17.96 ± 1.15) and 40 subjects in control group (K) (the average age of 44.40 ± 0.98 and the average years of employment 19.67 ± 0.98 years) which were not exposed to genotoxic agents in their workplaces. The results showed that frequencies of CA and PCD were statistically significantly higher in subjects exposed to radionuclides than in the control group (Mann-Whitney U test, P [sr

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

Separate Location of Parental Chromosomes in Squashed Metaphases of Hybrid between Hordeum vulgare L. and Four Polyploid, Alien Species

DEFF Research Database (Denmark)

Jensen, J.; Linde-Laursen, Ib

1984-01-01

In 38 squashed, somatic metaphases of four hybrids between diploid Hordeum vulgare and two tetra-and two hexaploid alien species, each of the H. vulgare chromosomes was identifed, and differentiated from the chromosomes of the other parental species, by its Giemsa C-banding pattern. The H. vulgare...

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)

Chromosomal aberration in peripheral lymphocytes and doses to the active bone marrow in radiotherapy of prostate cancer

International Nuclear Information System (INIS)

Gershkevitsh, E.; Trott, K.R.

2002-01-01

Purpose: Radiotherapy plays an important role in the management of prostate cancer. Epidemiological data indicate a small but significant risk of radiation-induced leukemia after radiotherapy which might be related to the high mean bone marrow dose associated with radiotherapy of prostate cancer. The purpose of the study was to investigate the relation between the mean bone marrow dose and unstable chromosome aberrations in peripheral blood lymphocytes in patients undergoing conformal radiotherapy for prostate cancer as a possible indicator of risk. Endometrial cancer patients were also included for comparison. Patients and Methods: Nine patients, six with prostate cancer (60-73 years old) and three with endometrial cancer (61-81 years old) treated with radiotherapy were included in the study. The non-bony spaces inside the pelvic bones were outlined on every CT slice using the treatment planning system and mean doses to the bone marrow calculated. Blood samples of the patients were obtained at different times before, during and at the end of treatment. Lymphocytes were cultured in the usual way and metaphases scored for dicentric aberrations. Results: 46 samples from nine patients were obtained. The mean number of metaphases analyzed per sample was 180 with a range from 52 to 435. The mean bone marrow doses for prostate cancer patients ranged from 2.8 to 4.2 Gy and for endometrial cancer patients from 12.8 to 14.8 Gy. The aberration yield increased with the planning target volume and the mean bone marrow dose. Conclusion: The yield of dicentric aberrations for prostate cancer patients correlated closely with the mean bone marrow dose albeit the induction of dicentrics occurred in mature T lymphocytes most of which were probably in transit through the irradiated volumes. Therefore, the observed relationship between dicentrics and mean bone marrow doses are indirect. (orig.) [de

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)

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 mobile phone users in Tamilnadu, southern India

International Nuclear Information System (INIS)

Balachandar, V.; Lakshman Kumar, B.; Suresh, K.; Sangeetha, R.; Manikantan, P.; Sasikala, K.

2007-01-01

Complete text of publication follows. Radiofrequency (RF) waves have long been used for different types of information exchange via the airwaves-wireless Morse code, radio, television, and wireless telephony. Increasingly larger numbers of people rely on mobile telephone technology, and health concerns about the associated RF exposure have been raised, particularly because the mobile phone handset operates in close proximity to the human body, and also because large numbers of base station antennas are required to provide widespread availability of service to large populations. In the present study chromosomal damage investigations were carried out on the peripheral blood lymphocytes of individuals using mobile phones, being exposed to MW frequency ranging from 800 to 2000 MHz. The aim of this study is to establish whether mobile phone use (n = 27) increases the frequency of chromosome aberrations (CA) in peripheral blood lymphocytes compared with controls (n = 27) in Tamilnadu, India. After signing a consent form, volunteers provided blood samples (5 ml) to establish cell cultures at 52 hrs. For CA analysis, 100 complete metaphase cells from each subject were evaluated. In the present study, in mobile phone users highly significant results were obtained when compared to control groups. These results highlight a correlation between mobile phone use (exposure to RFR) and genetic damage and require interim public health actions in the wake of widespread use of mobile telephony.

Structural analysis of γ radiation-induced chromosomal aberrations observed by atomic force microscopy

International Nuclear Information System (INIS)

Qu Shuang; Chen Ying; Ge Shili; Liu Xiulin; Zhou Pingkun; Zhang Sa; Zhang Detian

2003-01-01

Objective: To find a new method for the measurement of radiation-induced damage, the structures of normal chromosomes and 60 Co γ-ray-induced chromosomal aberration were analyzed by atomic force microscopy. Methods: Normal and irradiated chromosomes of human peripheral blood lymphocytes were prepared, then three-dimensional structure and height of chromosomes were analyzed by atomic force microscopy. Results: Three-dimensional structures of normal chromosomes and dicentric aberration in irradiated chromosomes were observed clearly. The data of chromosome height were helpful to recognizing the dicentric aberrations. Conclusion: Atomic force microscopy providing three-dimension image and linear measurement is a new and valuable tool for structural analysis of radiation-induced chromosomal aberrations

Induction and persistence of chromosome aberrations in human lymphocytes exposed to neutrons in vitro or in vivo: Implications of findings in 'retrospective' biological dosimetry

International Nuclear Information System (INIS)

Littlefield, L.G.; McFee, A.F.; Sayer, A.M.; O'Neill, J.P.; Kleinerman, R.A.; Maor, M.H.

2000-01-01

The induction and persistence were evaluated of chromosome aberrations in lymphocytes exposed in vitro to highly efficient 1 MeV monoenergetic neutrons and in patients who received fast neutrons as therapy for tumours. For the in vitro studies, lymphocytes were exposed to various doses of neutrons and cultured for one or 20 cell cycles. Aberrations were quantified in painted chromosome pairs 1, 2 or 4. These 1 MeV neutrons were highly efficient in inducing aberrations, and dicentrics as well as one-way and two-way translocations increased as a linear function of dose. About 30% of the aberrant metaphases displayed complex aberrations. After multiple in vitro cell divisions, virtually all asymmetrical aberrations had been eliminated from the cell population, and the frequency of one-way translocations was reduced dramatically. In contrast, most two-way translocations apparently survived through multiple cell divisions and still displayed excellent correlation with dose after 20 cell cycles. Classical methods were used to evaluate persistence of aberrations in patients who received fractionated neutron therapy to tumours located in many different sites. Neutron induced dicentrics and rings disappeared from the peripheral circulation within the first three years after exposure, while translocations persisted for more than 17 y. However, considerable variability in numbers of aberrations were observed between patients who had received similar 'average bone marrow doses'. Results of these studies are discussed in relation to the possible use of translocations as retrospective dosemeters in persons exposed to radiation many years ago. (author)

Hidden chromosomal abnormalities in pleuropulmonary blastomas identified by multiplex FISH

International Nuclear Information System (INIS)

Quilichini, Benoit; Andre, Nicolas; Bouvier, Corinne; Chrestian, Marie-Anne; Rome, Angelique; Intagliata, Dominique; Coze, Carole; Lena, Gabriel; Zattara, Helene

2006-01-01

Pleuropulmonary blastoma (PPB) is a rare childhood dysontogenetic intrathoracic neoplasm associated with an unfavourable clinical behaviour. We report pathological and cytogenetic findings in two cases of PPB at initial diagnosis and recurrence. Both tumors were classified as type III pneumoblastoma and histological findings were similar at diagnosis and relapse. In both cases, conventional cytogenetic techniques revealed complex numerical and structural chromosomal abnormalities. Molecular cytogenetic analysis (interphase/metaphase FISH and multicolor FISH) identified accurately chromosomal aberrations. In one case, TP53 gene deletion was detected on metaphase FISH. To date, only few cytogenetic data have been published about PPB. The PPB genetic profile remains to be established and compared to others embryonal neoplasia. Our cytogenetic data are discussed reviewing cytogenetics PPBs published cases, illustrating the contribution of multicolor FISH in order to identify pathogenetically important recurrent aberrations in PPB

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

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)

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

Direct fluorescence in situ hybridization on human metaphase chromosomes using quantum dot-platinum labeled DNA probes

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Hwang, Gyoyeon [Chemical Kinomics Research Center, Future Convergence Research Division, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Biological Chemistry, Korea University of Science and Technology, 217, Gajeong-ro, Yuseong-gu, Deajeon (Korea, Republic of); Lee, Hansol [Chemical Kinomics Research Center, Future Convergence Research Division, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Lee, Jiyeon, E-mail: jylee@kist.re.kr [Chemical Kinomics Research Center, Future Convergence Research Division, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Biological Chemistry, Korea University of Science and Technology, 217, Gajeong-ro, Yuseong-gu, Deajeon (Korea, Republic of)

2015-11-13

The telomere shortening in chromosomes implies the senescence, apoptosis, or oncogenic transformation of cells. Since detecting telomeres in aging and diseases like cancer, is important, the direct detection of telomeres has been a very useful biomarker. We propose a telomere detection method using a newly synthesized quantum dot (QD) based probe with oligonucleotide conjugation and direct fluorescence in situ hybridization (FISH). QD-oligonucleotides were prepared with metal coordination bonding based on platinum-guanine binding reported in our previous work. The QD-oligonucleotide conjugation method has an advantage where any sequence containing guanine at the end can be easily bound to the starting QD-Pt conjugate. A synthesized telomeric oligonucleotide was bound to the QD-Pt conjugate successfully and this probe hybridized specifically on the telomere of fabricated MV-4-11 and MOLT-4 chromosomes. Additionally, the QD-telomeric oligonucleotide probe successfully detected the telomeres on the CGH metaphase slide. Due to the excellent photostability and high quantum yield of QDs, the QD-oligonucleotide probe has high fluorescence intensity when compared to the organic dye-oligonucleotide probe. Our QD-oligonucleotide probe, conjugation method of this QD probe, and hybridization protocol with the chromosomes can be a useful tool for chromosome painting and FISH. - Highlights: • We prepared a probe linked between QD and telomeric oligonucleotide with platinum-guanine bonding. • Telomeres were detected by our new telomere probes successfully in three different human metaphase chromosomes. • QDPt-DNA probe has high fluorescence intensity in comparison with organic dye-DNA probe.

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

Evaluation of chromosome aberration frequency instable in individual groups residents at the municipality of Monte Alegre, Para, Brazil, exposed to radon; Avaliacao da frequencia de aberracoes cromossomicas instaveis em grupos de individuos residentes no municipio de Monte Alegre - PA expostos diferencialmente ao radonio

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Yunes, Samira Nogarol

2010-07-01

The municipality of Monte Alegre is a region that presents natural radiation high due to the presence of the radionuclide uranium ({sup 238}U) in its soil, which through its decay gives rise to element Rn, a gas. The radioactivity of the rocks has become a problem for the population of Monte Alegre, from the moment when the radioactive material began to be used in the construction of houses and paving of streets. Among all bio markers related to environmental exposures and its biological effects, the chromosomal aberrations are considered good bio markers as predictors of the risk of cancer. Studies suggest that the frequency of chromosomal aberrations may be related to the genetic instability individual and/or exposure to ionizing radiation. Our work aimed to evaluate the frequency of chromosomal aberrations in individuals in the region of high natural radioactivity in Monte Alegre-PA. As well as to correlate the cytogenetic analysis made in this study with the results of analysis of frequency of polymorphisms of genes of DNA repair carried out in another study that resulted in other dissertation. In accordance with the distribution of the data obtained in characterizing environmental radiological and in the calculation of dose, were chosen residents of homes with more and less exposure to radiation. The samples of peripheral blood of 85 individuals of the resident population of the region of Monte Alegre - PA were collected and examine provided two slides for individual was performed to verify the quality of the sample. Through this evaluation we decide that 33% of the material collected, or is, samples of 28 individuals were in suitable conditions for analysis of the frequency of chromosomal aberrations. After the collections lymphocytes present in the sample were cultivated in accordance with the methodology proposed for obtaining of cells in metaphase. were analyzed 6,177 metaphases of 28 individuals among which were found dicentric chromosomes 4 and 19

Chromosomal aberrations in Cynomolgus peripheral lymphocytes during and after fractionated whole-body γ-irradiation

International Nuclear Information System (INIS)

Guedeney, G.; Malarbet, J.L.; Doloy, M.T.

1989-01-01

Cynomolgus monkeys (Macaca fascicularis) were exposed to fractionated whole-body γ-irradiation at high and low dose rates for 4 or 5 weeks. The time-dependence of chromosomal aberrations was studied in relation to the number of lymphocytes during irradiation and after exposure for periods of up to about 600 days for chromosomal aberrations and 200 days for lymphocyte counts. Additivity of the daily effects on the number of chromosomal aberrations was observed during the exposures. Immediately after the end of the exposures the number of chromosomal aberrations decreased to reach low values. The disappearance of chromosomal aberrations seemed to be related to recovery of the lymphocyte counts. The data presented here emphasize the different kinetic patterns of chromosomal aberrations after fractionated and acute irradiation. (author)

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)

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

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)

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

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

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.)

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)

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

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

Dicentric chromosome aberration analysis using giemsa and centromere specific fluorescence in-situ hybridization for biological dosimetry: An inter- and intra-laboratory comparison in Indian laboratories

International Nuclear Information System (INIS)

Bhavani, M.; Tamizh Selvan, G.; Kaur, Harpreet; Adhikari, J.S.; Vijayalakshmi, J.; Venkatachalam, P.; Chaudhury, N.K.

2014-01-01

To facilitate efficient handling of large samples, an attempt towards networking of laboratories in India for biological dosimetry was carried out. Human peripheral blood samples were exposed to 60 Co γ-radiation for ten different doses (0–5 Gy) at a dose rate of 0.7 and 2 Gy/min. The chromosomal aberrations (CA) were scored in Giemsa-stained and fluorescence in-situ hybridization with centromere-specific probes. No significant difference (p>0.05) was observed in the CA yield for given doses except 4 and 5 Gy, between the laboratories, among the scorers and also staining methods adapted suggest the reliability and validates the inter-lab comparisons exercise for triage applications. - Highlights: • This is the first report from India on Networking for Biological Dosimetry preparedness using dicentric chromosomal (DC) aberration assay. • There is no significant difference in the in vitro dose response curve (Slope, Intercept, Curvature) constructed among the two labs. • No significant variation in the scoring of DC aberrations between the scorers irrespective of labs. • The DC results obtained by the labs from the Giemsa stained metaphase preparations were confirmed with centromere specific-FISH for further reliability and validity

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)

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...

Descriptive evaluation of chromosome aberrations in blood lymphocytes due to gamma-irradiation

International Nuclear Information System (INIS)

Medina III, F.S.; Gregorio, J.S.; Vinoya, P.C.; Panlaque, C.A.

1983-01-01

To induce and evaluate the effect of radiation among Filipinos, frequencies and types of ν-ray induced chromosome aberrations were studied with peripheral lymphocytes from 19 donors. Peripheral blood samples were irradiated at 0 Gray, 500 mGy, 1 Gy, 2 Gy, 3 Gy and 4 Gy. Irradiated blood samples were cultured by the same standard technique as that commonly used for human blood lymphocytes. Our observations showed that irradiation causes chromosomal aberration similar to effects observed in Caucasians. Our study confirm that irradiation causes an increase of the chromosome aberrations types normally found in the control (gaps, chromatid breaks and chromosome fragments) and can induce aberrations which are rarely observed in non-exposed individual (deletions, translocations, polycentrics, rings, and despiralizations). (author)

Radiation induced chromosome aberrations and interphase DNA geometry

International Nuclear Information System (INIS)

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

1995-01-01

Ionizing radiation induces DNA double strand breaks (DSBs) and their interaction and illegitimate recombination produces chromosome aberrations. Stable chromosome aberrations comprise inter-chromosomal events (translocations) and intra-chromosomal events (inversions). Assuming DSBs induction and interaction is completely random and neglecting proximity effects, the expected ratio of translocations to inversions is F=86, based on chromosome arm lengths. We analyzed the number of translocations and inversions using G-banding, in 16 lymphocyte cultures from blood samples acutely irradiated with γ-rays (dose range: 0.5Gy-3Gy). Our results give 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 an extra probability of interaction. 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. We assume a DSBs interaction probability function with cut-off length = 1 μ. We propose that large spread in F data could be due to temporal variation in overlapping and spatial chromosome confinement. (author). 14 refs

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 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....

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

40 CFR 799.9537 - TSCA in vitro mammalian chromosome aberration test.

Science.gov (United States)

2010-07-01

... effects are clear but do not immediately reveal the identity of the coded slides to the reader. Examples... if applicable. (H) Modal number of chromosomes. (iv) Test conditions. (A) Identity of metaphase... Mutation Assay. Environmental Mutagenesis 5, 795-801 (1983). (17) Locke-Huhle, C. Endoreduplication in...

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

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

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.

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)

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.

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)

Effect of x-rays on the somatic chromosomes of the exotic fish, Tilapia mossambica

Energy Technology Data Exchange (ETDEWEB)

Manna, G.K.; Som, R.C. (Kalyani Univ. (India). Dept. of Zoology)

1982-03-01

Male and female T. mossambica were x-rayed with 100 r and the metaphase chromosome aberrations in their gill epithelia were studied at 13 different intervals against suitable control. The chromosomes of males appeared more radio-sensitive than those of females. Among the diploid complement of 44 chromosomes, the individual type aberrations were non-random in both sexes. The longest pair of chromosomes, taken as the marker pair, was found very highly radio-sensitive, while the remaining 21 pairs as non-markers were somewhat resistant to x-radiation when the observed and the expected numbers were subjected to statistical analysis. The break in the marker chromosome was also non-randomly distributed as the distal half had a significantly large number of breaks.

[Chromosome banding analysis of peripheral blood lymphocytes stimulated with IL2 and CpG oligonucleotide DSP30 in patients with chronic lymphocytic leukemia].

Science.gov (United States)

Stěpanovská, K; Vaňková, G; Némethová, V; Tomášiková, L; Smuhařová, P; Divíšková, E; Vallová, V; Kuglík, P; Plevová, K; Oltová, A; Doubek, M; Pospíšilová, S; Mayer, J

2013-01-01

Chromosomal aberrations play an important role as prognostic factors in chronic lymphocytic leukemia (CLL). These aberrations are mostly detected by fluorescent in situ hybridization (FISH), as chromosomal banding analysis has been scarce due to low proliferative activity of malignant B-lymphocytes in vitro. In 2006, a new method using stimulation with IL-2 and CpG oligonucleotide DSP30 for metaphase generation in CLL was published [1]. The objective of our study was to verify the efficacy of stimulation and to evaluate if the method is suitable for routine diagnostics. In total, peripheral blood samples of 369 CLL patients were analyzed in parallel by chromosomal banding analysis and by FISH probes for 13q14, 11q22-23, CEP12 and 17p13. Out of 369 patients, 307 (83%) were successfully stimulated for metaphase generation. Chromosomal aberrations were detected in 243 (79%) out of 307 patients evaluated by chromosomal banding analysis. Other aberrations that are not included into standard FISH panel were detected in patients karyotypes, e.g. del(6q), del(14q), t(14;18)(q32;q21), t(11;14)(q13;q32) and t(18;22)(q21;q11). One hundred and three (42%) patients showed complex aberrant karyotype not detected by FISH analysis. Stimulation with IL-2 and oligonucleotide DSP30 is an efficient method how to induce proliferation of malignant B-lymphocytes and allows detection of a substantial number of chromosomal aberrations in addition to those detected by standard FISH panel. Using this method in routine diagnostics is helpful particularly in identification of patients with complex aberrant karyotype.

Sister chromatid exchange analysis and chromosoma aberration studies in interventional cardiology laboratory workers. One year follow up study

International Nuclear Information System (INIS)

Erol, M.K.; Oztas, S.; Bozkurt, E.; Karakelleoglu, S.

2002-01-01

Invasive cardiology laboratory workers are occupationally exposed to chronic ionizing radiation. It is known that ionizing radiation has a damaging effect on chromosomes. In present study, we investigated the frequency of sister chromatid exchange (SCE) and chromosomal aberrations in 11 invasive cardiology laboratory workers and 11 healthy controls. After a vacation period, we took blood samples for chromosome analysis in months 0, 4, 8 and 12 (last two month period was the nonradiation time). The SCE frequencies did not change significantly after exposure to ionizing radiation in any worker. Our study has revealed that non-specific structural chromosome aberrations such as gaps, isogaps, acentric chromosomes, chromatids and chromosome breakage could be in the 4th and 8th months after ionizing radiation exposure in the metaphase plaques. All abnormal chromosomal effects had disappeared by the end of the two month non-exposure period in each worker. In conclusion, the results suggest that SCE frequencies are not significantly affected in invasive cardiology laboratory workers who are exposed occupationally to ionizing radiation, although some degree of reversible chromosomal aberrations did appear. (author)

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

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.

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.

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

Energy Technology Data Exchange (ETDEWEB)

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.

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)

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)

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

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.

Radiation exposure and chromosome damage

International Nuclear Information System (INIS)

Lloyd, D.

1979-01-01

Chromosome damage is discussed as a means of biologically measuring radiation exposure to the body. Human lymphocytes are commonly used for this test since the extent of chromosome damage induced is related to the exposure dose. Several hundred lymphocytes are analysed in metaphase for chromosome damage, particularly dicentrics. The dose estimate is made by comparing the observed dicentric yield against calibration curves, previously produced by in vitro irradiation of blood samples to known doses of different types of radiation. This test is useful when there is doubt that the film badge has recorded a reasonable whole body dose and also when there is an absence of any physical data. A case of deliberate exposure is described where the chromosome damage test estimated an exposure of 152 rads. The life span of cell aberrations is also considered. Regular checks on radiotherapy patients and some accidental overdose cases have shown little reduction in the aberration levels over the first six weeks after which the damage disappears slowly with a half-life of about three years. In conclusion, chromosome studies have been shown to be of value in resolving practical problems in radiological protection. (U.K.)

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

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

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

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

Chromosomal instability in mouse embryonic fibroblasts null for the transcriptional co-repressor Ski.

Science.gov (United States)

Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J

2012-01-01

Ski is a transcriptional regulator that has been considered an oncoprotein given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski-/- mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chromatin/chromosome bridges as the major cause of micronuclei (MN) formation and the subsequent aneuploidy. Although these cells arrested in mitosis after treatment with spindle disrupting drugs and exhibited a delayed metaphase/anaphase transition, spindle assembly checkpoint (SAC) was not sufficient to prevent chromosome missegregation, consistent with a weakened SAC. Our in vivo analysis also showed dynamic metaphase plate rearrangements with switches in polarity in cells arrested in metaphase. Importantly, after ectopic expression of Ski the cells that displayed this metaphase arrest died directly during metaphase or after aberrant cell division, relating SAC activation and mitotic cell death. This increased susceptibility to undergo mitosis-associated cell death reduced the number of MN-containing cells. The presented data support a new role for Ski in the mitotic process and in maintenance of genetic stability, providing insights into the mechanism of tumor suppression mediated by this protein. Copyright © 2011 Wiley Periodicals, Inc.

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

Chromosome aberrations induced by 135 MeV of carbon and neon beams by PRC

International Nuclear Information System (INIS)

Ohara, Hiroshi; Minamihisamatu, Masako; Kanai, Tatsuaki; Eguchi-Kasai, Kiyomi; Itsukaichi, Hiromi; Fukutsu, Kumiko; Yatagai, Fumio; Sato, Kohki.

1993-01-01

Radiation-induced chromosome aberration can be an indicator of the radiation lesions in irradiated cells. Many studies on chromosome aberration induced by X-ray and γ - ray have indicated that the dose response of the aberration can be fitted to a quadratic equation, Y = αD + βD 2 , and it becomes linear as the LET of beams increases. The main subject of this study was some quantification of chromosomal aberration induced by 135 MeV/n carbon and neon beams produced by the RRC, the operation of which increasingly became useful for the studies on heavy ion biology. The results will meet with some of the radiobiological features connected to the specific action of charged particles. The materials used, the experimental method and the results are reported. Four curves of the dose response for the production of dicentric and ring types of aberration induced by carbon and neon beams and four different dose average LETs are given. Aberration production rate became higher as LET increased. Chromosome aberration can be quantified as an indicator of radiation lesions in the case of high LET particle radiation. (K.I.)

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

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)

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.

Chromosomal aberrations as etiological factors of intrauterine growth retardation

Directory of Open Access Journals (Sweden)

Petrović Bojana

2008-01-01

Full Text Available Background/Aim. Intrauterine growth retardation (IUGR is a pathological condition of pregnancy characterised by birth weight below the 10th centile. A number of fetal, placental and maternal causes can lead to IUGR; although, in most cases no specific causes can be identified. The aim of this study was to determine the part of chromosomal abnormalities in IUGR etiology. Methods. Fetal blood karyotype taken by cordocentesis from 168 fetuses with diagnosed IUGR was analyzed. Results. Chromosomal rearrangements both numerical and structural were detected in 14 cases (12.2%. Two cases were triploid. Patau syndrome, Edwards syndrome and Down syndrome were found in two cases each. There was one case of trisomy 7 (47, XY, +7 and one case of trisomy 16 (47, XX, +16; one translocation, 46, XY, t (2; 14(q23; q32 and a deletion 46, XYdel (12 (p12 as well as two cases of sex chromosomes abnormalities, 45, X (Turner syndrome and 47, XYY. Conclusion. These findings suggest that a consistent number of symmetrical IUGR cases (about 12% can be associated with chromosomal rearrangements. Chromosomal aberrations that cause IUGR are heterogeneous, aberration of autosomes, mostly autosomal trisomies, being the most common.

Cellular origin of prognostic chromosomal aberrations in AML patients

DEFF Research Database (Denmark)

Mora-Jensen, H.; Jendholm, J.; Rapin, N.

2015-01-01

chromosomal structural rearrangements and single nucleotide variants (SNVs). Conventional AML diagnostics and recent seminal next-generation sequencing (NGS) studies have identified more than 200 recurrent genetic aberrations presenting in various combinations in individual patients. Significantly, many...... of these aberrations occur in normal hematopoietic stem and progenitor cells (HSCs/HPCs) before definitive leukemic transformation through additional acquisition of a few (that is, mostly 1 or 2) leukemia-promoting driver aberrations. NGS studies on sorted bone marrow (BM) populations of AML patients with a normal...

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)

The Y chromosome of the Atelidae family (Platyrrhini): study by chromosome microdissection.

Science.gov (United States)

Gifalli-Iughetti, C; Koiffmann, C P

2009-01-01

In order to study the intergeneric variability of the Y chromosome, we describe the hybridization of the Y chromosome of Brachytelesarachnoides, obtained by microdissection, to metaphases of Atelesbelzebuthmarginatus, Lagothrixlagothricha, and Alouatta male specimens. Brachytelesarachnoides (Atelinae) has 62 chromosomes and a very small Y chromosome. Our results showed that the Brachytelesarachnoides Y chromosome probe hybridized to Lagothrixlagothricha metaphases yielding one hybridization signal on only the tiny Y chromosome, and when hybridized with Atelesbelzebuthmarginatus metaphases it yielded one hybridization signal on two thirds of the small acrocentric Y chromosome. However, no hybridization signal was observed in Alouatta metaphases (subfamily Alouattinae), a closely related genus in the Atelidae family. Furthermore, our data support a close phylogenetic relationship among Brachyteles, Ateles, and Lagothrix and their placement in the Atelinae subfamily, but exclude Alouatta from this group indicating its placement as basal to this group. Copyright 2009 S. Karger AG, Basel.

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)

Bayesian analysis of overdispersed chromosome aberration data with the negative binomial model

International Nuclear Information System (INIS)

Brame, R.S.; Groer, P.G.

2002-01-01

The usual assumption of a Poisson model for the number of chromosome aberrations in controlled calibration experiments implies variance equal to the mean. However, it is known that chromosome aberration data from experiments involving high linear energy transfer radiations can be overdispersed, i.e. the variance is greater than the mean. Present methods for dealing with overdispersed chromosome data rely on frequentist statistical techniques. In this paper, the problem of overdispersion is considered from a Bayesian standpoint. The Bayes Factor is used to compare Poisson and negative binomial models for two previously published calibration data sets describing the induction of dicentric chromosome aberrations by high doses of neutrons. Posterior densities for the model parameters, which characterise dose response and overdispersion are calculated and graphed. Calibrative densities are derived for unknown neutron doses from hypothetical radiation accident data to determine the impact of different model assumptions on dose estimates. The main conclusion is that an initial assumption of a negative binomial model is the conservative approach to chromosome dosimetry for high LET radiations. (author)

Spontaneous and X-ray induced chromosomal aberrations in selected connective tissue diseases

International Nuclear Information System (INIS)

Burkhardt, W.C.; Jackson, J.F.; Songcharoen, S.; Meydrech, E.F.

1980-01-01

Chromosome studies were performed on peripheral blood lymphocytes of 28 patients with connective tissue disease (6 with progressive systemic sclerosis, 6 with systemic lupus erythematosus, 6 with anti-nuclear antibody positive rheumatoid arthritis, 6 with anti-nuclear antibody negative rheumatoid arthritis, and 4 with mixed connective tissue disease) and on 17 controls to determine the frequency of spontaneous as well as X-ray (75 rads) induced aberrations. The mean spontaneous chromosomal aberration frequency for the 28 patients (9.1%) was significantly (P=0.038) greater than that of controls (6.4%). When patients were categorized into specific clinically designated connective tissue disease subdivisions for comparison with the controls, only X-irradiated cells from the progressive systemic sclerosis group displayed significantly elevated levels of total chromosomal aberrations over those of the control group. The X-irradiated lymphocytes from these patients had an average of 23.6% aberrations per patient, while those of the control group showed an average of 14.9% per patient (P<0.05). (author)

Spontaneous and X-ray induced chromosomal aberrations in selected connective tissue diseases

Energy Technology Data Exchange (ETDEWEB)

Burkhardt, W C; Jackson, J F; Songcharoen, S; Meydrech, E F [Mississippi Univ., Jackson (USA). Medical Center

1980-01-01

Chromosome studies were performed on peripheral blood lymphocytes of 28 patients with connective tissue disease (6 with progressive systemic sclerosis, 6 with systemic lupus erythematosus, 6 with anti-nuclear antibody positive rheumatoid arthritis, 6 with anti-nuclear antibody negative rheumatoid arthritis, and 4 with mixed connective tissue disease) and on 17 controls to determine the frequency of spontaneous as well as X-ray (75 rads) induced aberrations. The mean spontaneous chromosomal aberration frequency for the 28 patients (9.1%) was significantly (P=0.038) greater than that of controls (6.4%). When patients were categorized into specific clinically designated connective tissue disease subdivisions for comparison with the controls, only X-irradiated cells from the progressive systemic sclerosis group displayed significantly elevated levels of total chromosomal aberrations over those of the control group. The X-irradiated lymphocytes from these patients had an average of 23.6% aberrations per patient, while those of the control group showed an average of 14.9% per patient (P<0.05).

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)

A study of chromosomal aberrations in amniotic fluid cell cultures.

Science.gov (United States)

Wolstenholme, J; Crocker, M; Jonasson, J

1988-06-01

This paper represents the analysis of 1916 routine amniotic fluid specimens harvested by an in situ fixation technique in a prospective study with regard to cultural chromosome anomalies. Excluding constitutional abnormalities, 2.9 per cent of 19,432 cells analysed showed some form of chromosome anomaly, terminal deletions (57 per cent) and chromatid/chromosome breaks and gaps (18 per cent) being the most frequent, followed by interchange aberrations (13 per cent) and trisomy (5 per cent). No case was found of more than one colony from the same culture showing the same anomaly without it being present in other cultures from the same fluid. The wholly abnormal colonies had a surplus of trisomies and from the mathematical considerations presented one may infer that these are likely to reflect the presence of abnormal cells in the amniotic fluid. Partly abnormal colonies appeared at a frequency that would correspond to virtual absence of selection against chromosomally abnormal cells when cultured in vitro. The aberrations found were similar to those seen as single cell anomalies, except for chromatid breaks and exchanges. The data suggest a basic preferential induction of trisomy for chromosomes 2, 18, 21, and the Y-chromosome. Structural aberrations showed a marked clustering of breakpoints around the centromeres. The frequency of mutant cells was low (1.4 X 10(-3)) before culture was initiated. At harvest, the frequency of abnormal cells was much higher (3 X 10(-2)) corresponding to 3 X 10(-3) mutations per cell per generation accumulating over approximately ten generations in vitro.

Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

NARCIS (Netherlands)

Ji, X.

2014-01-01

Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana.

I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and

Semi-automated detection of aberrant chromosomes in bivariate flow karyotypes

NARCIS (Netherlands)

Boschman, G. A.; Manders, E. M.; Rens, W.; Slater, R.; Aten, J. A.

1992-01-01

A method is described that is designed to compare, in a standardized procedure, bivariate flow karyotypes of Hoechst 33258 (HO)/Chromomycin A3 (CA) stained human chromosomes from cells with aberrations with a reference flow karyotype of normal chromosomes. In addition to uniform normalization of

Radiation-induced chromosome aberrations and cell killing in normal human fibroblasts and ataxia telangiectasia fibroblasts

International Nuclear Information System (INIS)

Kawata, T.; Saito, M.; Uno, T.; Ito, H.; Shigematsu, N.

2003-01-01

Full text: When cells are held in a non-dividing state (G0) after irradiation, an enhanced survival can be observed compared to that of immediate plating. A change of survival depending on post irradiation condition is known to be repair of potentially lethal damage (RPLD). The effects of confluent holding recovery (24-h incubation following irradiation) on chromosome aberrations in normal human fibroblasts (AG1522) and ataxia telangiectasia fibroblasts (GM02052C) were examined. A chemical-induced premature chromosome condensation (PCC) technique with fluorescent in situ hybridization (FISH) was applied to study chromosome aberrations in G2 and M-phase. Results from cell survival showed that the capacity for potentially lethal damage repair was normal in AG1522 cells but very little in GM02052C cells. The frequency of chromosome aberrations in AG1522 cells decreased when cells were allowed to repair for 24-h. Especially complex type exchanges were found to decrease markedly at high doses (4Gy and 6Gy). However, the frequency of chromosome aberrations including complex type exchanges showed little decrease in GM02052C cells. Confluent holding can effectively reduce chromosome aberrations, especially complex type exchanges in normal cells

Protective Effect of Curcumin on γ - radiation Induced Chromosome Aberrations in Human Blood Lymphocytes

International Nuclear Information System (INIS)

AlSuhaibani, E.S

2008-01-01

The present work is aimed at evaluating the radioprotective effect of curcumin on γ radiation induced genetic toxicity. The DNA damage was analyzed by the frequencies of chromosome aberrations assay. Human lymphocytes were treated in vitro with 5.0 γg/ml of curcumin for 30 min at 37 degree C then exposed to 1, 2 and 4 Gy gamma-radiation. The lymphocytes which were pre-treated with curcumin exhibited a significant decrease in the frequency of chromosome aberration at 1 and 2 Gy radiation-induced chromosome damage as compared with the irradiated cells which did not receive the curcumin pretreatment. Thus, pretreatment with curcumin gives protection to lymphocytes against γ-radiation induced chromosome aberration at certain doses. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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)

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.

X-ray induction of mitotic and meiotic chromosome aberrations

International Nuclear Information System (INIS)

Yao, K.T.S.

1980-01-01

In 1964 six pairs of rat kangaroo (Potorous tridactylis) were obtained from Australia. The tissues of these animals were used to initiate cell lines. Since this species has a low chromosome number of six pairs, each pair with its own distinctive morphology, it is particularly favorable for cytogenetic research. In cell cultures derived from the corneal endothelial tissues of one animal there emerged a number of haploid cells. The number of haploid cells in the cultures reached as high as 20% of the total mitotic configurations. The in vitro diploid and haploid mixture cell cultures could be a resemblance or a coincidence to the mixture existence of the diploid primary spermatocytes and the haploid secondary spermatocytes (gametes) in the in vivo testicular tissues of the male animals. It would be interesting to compare reactions of the haploid and diploid cell mixture, either in the cultures or in the testes, to x-ray exposure. Two other studies involving x-ray effects on Chinese hamster oocyte maturation and meiotic chromosomes and the x-ray induction of Chinese hamster spermatocyte meiotic chromosome aberrations have been done in this laboratory. A review of these three studies involving diploid and haploid chromosomes may lead to further research in the x-ray induction of chromosome aberrations

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

Frequency of chromosomal aberrations in a group of patients carriers of gonosomopathies

International Nuclear Information System (INIS)

Quesada Dorta, Marlen; Bello Alvarez, Daisy; Gonzalez Fernandez, Pedro

2004-01-01

This paper was aimed at determining the frequency of chromosomal aberrations in a group of patients carriers of gonosomopathies and at relating in each case the meaning of the different chromosomal aberrations found to the patients' clinical diagnosis. 656 patients with presumptive diagnosis of gonosomopathies from different hospital institutions of the country that were received at the molecular genetics laboratory of Hermanos Ameijeiras Clinical and Surgical Hospital from 1982 to 2001, were studied. Of the total of patients with presumptive diagnosis of gonosomopathies, in 32.7 % (215/656) the clinical diagnosis was confirmed by the cytogenetic study. The chromosomal study was conducted by using G band techniques. The chromosomal rearrangements found were classified into 4 groups. The group of numerical gonosomopathies showed the highest frequency with 110 patients, accounting for 51 % of the total. It was followed by the group of numerical and structural alterations (mosaics) with 59 patients (27.0), the inversions of sex with 24 patients (12.0), and the group of structural gonosomopathies with 22 patients (10.0) The most common chromosomal aberrations were the numerical gonosomopathies (Turner and Klinefelter's syndrome). The chromosomal study in these patients is a very important diagnostic value indicator for the therapeutical conduct to be followed in every case

Study on chromosome aberrations test determinated by micro-whole blood culture in vacuum blood collection tube

International Nuclear Information System (INIS)

Zhong Zhihong; Han Fang'an; Ge Qinjuan; Wu Xiao; Chen Juan

2006-01-01

Objective: To develop an easier and efficient method of culturing the chromosome and analyzing the aberrations in peripheral lymphocytes. Methods: Micro whole was cultured for 54 hours in home-made vacuum blood collection tube, and then collection, slice-making, microscopy detection for the chromosome aberrations was done. The difference of the results was analysed by comparing with the common method. Results: For 60 radiologists and 30 contrasts, the chromosome aberrations in peripheral lymphocytes were examed by this system, the lymphocytes and chromosome were clear and alive and easier to analyse. Compared with the common method, there was no significantly difference between the two analyzing results. Conclusion: The chromosome aberrations test by micro whole blood culture in vacuum blood collection tube is easier and efficient, and is worthy of being widely popularized. (authors)

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.

Sister chromatid exchanges and structural chromosome aberrations in lymphocytes in operating room personnel

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Husum, B; Niebuhr, E; Wulf, H C; Norgaard, I

1983-06-01

Information on possible chromosomal damage in humans after long-term exposure to trace concentrations of waste anaesthetic gases is scarce. We examined peripheral lymphocytes in operating room personnel for both chromosome aberrations and sister chromatid exchanges (SCE). Following a standardized procedure of cultivation and staining, 30 cells from each person were scored for SCE and 100 cells from each person were examined for chromosome aberrations. A total of 45 persons were examined, representing anaesthetists (n . 15), operating room nurses assisting the surgeon (n . 10), nurses circulating in the operating room (n . 8) and healthy, unexposed controls (n . 12). The median duration of working in the operating room was 102 months, respectively. Time-weighted concentration levels of 2.5-4.3 p.p.m. of halothane and 25-400 p.p.m. of nitrous oxide were measured in the breathing zones of the anaesthetists during mask anaesthesia. Examination of SCE and chromosome aberrations yielded corresponding qualitative results. With both tests, no statistically significant difference was observed between the four groups of persons. It was concluded that by examination of both SCE and chromosome aberrations in peripheral lymphocytes in operating room personnel, no indication was found of a mutagenic effect of long-term exposure to trace concentrations of waste anaesthetic gases.

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

Cytogenetic biological dosimetry in radiological protection: chromosome aberration analysis in human lymphocyties

International Nuclear Information System (INIS)

Campos, I.M.A. de.

1988-01-01

The effects of ionizing radiation on chromosomes have been know for several decades and dose effect relationships are also fairly well established for several doses and dose rates. Apart from its biological significance, the interpretation of chromosome aberration frequency associated with human exposure to radiation plays an important role in dose assessment, particularly in cases where exposure is though to have occurred but no physical dose monitoring system was present. Based on the cytogenetic data obtained from seven cases of exposure to radiation the aberration frequency have been fitted to the quadratic function Y= αD + βD 2 as the dose response curves from literature. The dose equivalent estimate by frequency of chromosomic aberration found here was compared with 60 Co and 192 Ir already published curves obtained at almost similar dose rate together with some hematological data. (author) [pt

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

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

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)

Frequency of chromosomal aberrations in workers occupationally exposed to ionizing radiations

International Nuclear Information System (INIS)

Spasojevic-Tisma, V.; Joksic, G.; Ilic, Z.; Milanovic, S.; Djuric, J.; Tisma, J.; Celeketic, D.; Cuknic, O.; Perisic, J.; Milacic, S.; Cuknic, O.)

2007-01-01

Subjects occupationally exposed to ionizing radiation (external exposition) are examined for chromosomal aberrations in peripheral blood lymphocytes in comparison to a control group. The average annual absorbed dose, measured by TLD dosimeters, for all three groups did not exceed 2mSv. Continuous exposure to small doses of ionizing radiation causes unstable aberrations in lymphocytes. In this research the largest number of found alterations are of acentric fragments and chromosomal breaks type. The highest occupational risk appears to be for subjects working in manufacturing of radio isotope technetium [sr

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

Leukemia-related clonal chromosome aberrations observed in A-bomb survivors. Deletion in chromosome 5 and inversion in chromosome 14

International Nuclear Information System (INIS)

Ohtaki, Kazuo

1999-01-01

Chromosome aberrations were analyzed by G differentiation staining method on about 5,400 peripheral lymphocytes of 168 A-bomb survivors, of whom 143 had been exposed to mean DS86 dose of 2.05 Gy (exposed group) and of 25, 0 Gy (control) and results concerning clonal growth of abnormal cells were described in this paper. G band analysis of the aberrations in T-lymphocytes revealed that frequency of translocation in the exposed group increased to 17 times of the control and deletion, 5 times. Deletion in chromosome 5 where tumor-suppressor gene was present, [del(5q-)], was found in about 30% of total deletions. Since patients of myelodysplasia syndrome and acute myelogenic leukemia had the deletion in more than 50%, growth of cells possessing it was suggestive of the progression of pre-leukemic step. Frequency of inversion in chromosome 14, inv(14)(q11q32), was as high as 80% of total 118 inversions of T-ALL (T-acute lymphocyte leukemia) and T-CLL (T-chronic LL) types in the exposed group. Therefore, the inversion also can be a pre-leukemic step. However, it was suggested that these aberrations were not sufficient for crisis of the disease, which required other factors.(K.H.)

Chromosome aberration assays in Allium

Energy Technology Data Exchange (ETDEWEB)

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.

Chromosome aberrations in human lymphocytes exposed to tritiated water in vitro

International Nuclear Information System (INIS)

Bocian, E.; Ziemba-zak, B.; Rosiek, O.; Sablinski, J.

1978-01-01

The induction of chromosome aberrations in human peripheral blood lymphocytes by tritiated water or 180 kV X-rays in vitro was studied. Lymphocytes were exposed to various concentrations of HTO for 2 h or for 53 h. Chromosome and chromatid type aberrations were scored during the first mitotic division after stimulation with phytohaemagglutinin. For the analysis of the dose-response relationship the data were fitted by the method of least-squares to different models. After acute exposure to tritium β-rays and X-rays, the dicentrics + centric rings and terminal + interstitial deletions gave the best fit to the linear-quadratic function. However, data for these types of aberrations after 53 h exposure to HTO gave equally good fit to the linear and linear-quadratic functions. The best description of the dose-response relationship for chromatid aberrations is given by the linear model. In the system studied the RBE of tritium β-rays as compared to 180 KV X-rays was 1.17+-0.02. (Auth.)

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

Chromosome aberration frequency in blood lymphocytes of animals with 239Pu lung burdens

International Nuclear Information System (INIS)

Brooks, A.L.; LaBauve, R.J.; McClellan, R.O.; Jensen, D.A.

1976-01-01

Other investigators have suggested a causal relationship between accidental 239 Pu exposures in man and the presence of chromosome aberrations in blood lymphocytes. For experimental assessment of this relationship, 16 rhesus monkeys and 171 Chinese hamsters were exposed to 239 PuO 2 aerosols and an additional five hamsters were injected with 239 Pu citrate, and the frequency of aberrations in blood lymphocyte was determined. Hamsters with the highest lung burden had a median survival time of about 80 days. No deaths occurred in any of the other treated hamsters or monkeys by 250 days after 239 Pu inhalation. Hamsters sacrificed at 30 days showed an increase in chromosome aberration frequency with increasing dose to lungs. By 120 days after inhalation, the aberration frequency in the controls was 0.012. The frequency in animals with doses that produced significant life shortening had decreased to 0.018 and to 0.032 aberration/cell in animals with lower doses. At 380 days after injection of 2 nCi of 239 Pu citrate per gram of body weight, hamster lymphocytes had an aberration frequency of 0.048 aberration/cell. The level of chromosome damage in the 239 PuO 2 -exposed monkeys at 30 and 90 days after inhalation was not different from that observed in controls. Possible reasons for differences between the experimental animal observations and findings in man are discussed

A genome-wide map of aberrantly expressed chromosomal islands in colorectal cancer

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Castanos-Velez Esmeralda

2006-09-01

Full Text Available Abstract Background Cancer development is accompanied by genetic phenomena like deletion and amplification of chromosome parts or alterations of chromatin structure. It is expected that these mechanisms have a strong effect on regional gene expression. Results We investigated genome-wide gene expression in colorectal carcinoma (CRC and normal epithelial tissues from 25 patients using oligonucleotide arrays. This allowed us to identify 81 distinct chromosomal islands with aberrant gene expression. Of these, 38 islands show a gain in expression and 43 a loss of expression. In total, 7.892 genes (25.3% of all human genes are located in aberrantly expressed islands. Many chromosomal regions that are linked to hereditary colorectal cancer show deregulated expression. Also, many known tumor genes localize to chromosomal islands of misregulated expression in CRC. Conclusion An extensive comparison with published CGH data suggests that chromosomal regions known for frequent deletions in colon cancer tend to show reduced expression. In contrast, regions that are often amplified in colorectal tumors exhibit heterogeneous expression patterns: even show a decrease of mRNA expression. Because for several islands of deregulated expression chromosomal aberrations have never been observed, we speculate that additional mechanisms (like abnormal states of regional chromatin also have a substantial impact on the formation of co-expression islands in colorectal carcinoma.

Sensitivity of Bidens laevis L. to mutagenic compounds. Use of chromosomal aberrations as biomarkers of genotoxicity

Energy Technology Data Exchange (ETDEWEB)

Perez, D.J. [Laboratorio de Genetica, Estacion Experimental Agropecuaria Balcarce (INTA), Facultad de Ciencias Agrarias, UNMdP, CC 276, 7620 Balcarce (Argentina); Laboratorio de Ecotoxicologia, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, UNMdP, Funes 3350, 7600 Mar del Plata (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Rivadavia 1917, 1033 Buenos Aires (Argentina); Lukaszewicz, G. [Laboratorio de Ecotoxicologia, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, UNMdP, Funes 3350, 7600 Mar del Plata (Argentina); Menone, M.L., E-mail: lujanm@mdp.edu.a [Laboratorio de Ecotoxicologia, Departamento de Ciencias Marinas, Facultad de Ciencias Exactas y Naturales, UNMdP, Funes 3350, 7600 Mar del Plata (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Rivadavia 1917, 1033 Buenos Aires (Argentina); Camadro, E.L. [Laboratorio de Genetica, Estacion Experimental Agropecuaria Balcarce (INTA), Facultad de Ciencias Agrarias, UNMdP, CC 276, 7620 Balcarce (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Rivadavia 1917, 1033 Buenos Aires (Argentina)

2011-01-15

The wetland macrophyte Bidens laevis possesses suitable cytological characteristics for genotoxicity testing. To test its sensitivity as compared to terrestrial plants species currently in use in standardized assays, Methyl Methanesulfonate (MMS), N-ethyl-N-nitrosourea (ENU) and Maleic Hydrazide (HM) were used. On the other hand, the insecticide Endosulfan (ES) - an environmentally relevant contaminant - was assayed in seeds and two-month old plants. Mitotic Index (MI), frequency of Chromosome Aberrations in Anaphase-Telophase (CAAT) and frequency of Abnormal Metaphases (AM) were analyzed. MH, MMS and ENU caused a significant decrease of the MI. MMS was aneugenic whereas MH and ENU were both aneugenic and clastogenic. ES caused a significant concentration-dependent increase of total- and aneugenic-CAAT in roots and a significant high frequency of AM at high concentrations. Because of its sensitivity to mutagenic substances, B. laevis can be regarded as a reliable and convenient species for genotoxicity assays especially if aquatic contaminants are evaluated. - The wetland macrophyte Bidens laevis is sensitive to genotoxic compounds similarly to terrestrial standardized species.

Sensitivity of Bidens laevis L. to mutagenic compounds. Use of chromosomal aberrations as biomarkers of genotoxicity

International Nuclear Information System (INIS)

Perez, D.J.; Lukaszewicz, G.; Menone, M.L.; Camadro, E.L.

2011-01-01

The wetland macrophyte Bidens laevis possesses suitable cytological characteristics for genotoxicity testing. To test its sensitivity as compared to terrestrial plants species currently in use in standardized assays, Methyl Methanesulfonate (MMS), N-ethyl-N-nitrosourea (ENU) and Maleic Hydrazide (HM) were used. On the other hand, the insecticide Endosulfan (ES) - an environmentally relevant contaminant - was assayed in seeds and two-month old plants. Mitotic Index (MI), frequency of Chromosome Aberrations in Anaphase-Telophase (CAAT) and frequency of Abnormal Metaphases (AM) were analyzed. MH, MMS and ENU caused a significant decrease of the MI. MMS was aneugenic whereas MH and ENU were both aneugenic and clastogenic. ES caused a significant concentration-dependent increase of total- and aneugenic-CAAT in roots and a significant high frequency of AM at high concentrations. Because of its sensitivity to mutagenic substances, B. laevis can be regarded as a reliable and convenient species for genotoxicity assays especially if aquatic contaminants are evaluated. - The wetland macrophyte Bidens laevis is sensitive to genotoxic compounds similarly to terrestrial standardized species.

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)

Evaluation of an automated karyotyping system for chromosome aberration analysis

International Nuclear Information System (INIS)

Prichard, H.M.

1987-01-01

Chromosome aberration analysis is a promising complement to conventional radiation dosimetry, particularly in the complex radiation fields encountered in the space environment. The capabilities of a recently developed automated karyotyping system were evaluated both to determine current capabilities and limitations and to suggest areas where future development should be emphasized. Cells exposed to radiometric chemicals and to photon and particulate radiation were evaluated by manual inspection and by automated karyotyping. It was demonstrated that the evaluated programs were appropriate for image digitization, storage, and transmission. However, automated and semi-automated scoring techniques must be advanced significantly if in-flight chromosome aberration analysis is to be practical. A degree of artificial intelligence may be necessary to realize this goal

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

Energy Technology Data Exchange (ETDEWEB)

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.

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.)

Meiotic drive on aberrant chromosome 1 in the mouse is determined by a linked distorter.

Science.gov (United States)

Agulnik, S I; Sabantsev, I D; Orlova, G V; Ruvinsky, A O

1993-04-01

An aberrant chromosome 1 carrying an inverted fragment with two amplified DNA regions was isolated from wild populations of Mus musculus. Meiotic drive favouring the aberrant chromosome was demonstrated for heterozygous females. Its cause was preferential passage of aberrant chromosome 1 to the oocyte. Genetic analysis allowed us to identify a two-component system conditioning deviation from equal segregation of the homologues. The system consists of a postulated distorter and responder. The distorter is located on chromosome 1 distally to the responder, between the ln and Pep-3 genes, and it acts on the responder when in trans position. Polymorphism of the distorters was manifested as variation in their effect on meiotic drive level in the laboratory strain and mice from wild populations.

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

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)

Effects of x-rays on growth of plants and mitotic chromosomal aberrations of Lathyrus sativus Linn

International Nuclear Information System (INIS)

Chaudhuri, D.; Das, A.

1985-01-01

It has been found that the abnormalities of chromosome at different stages of mitosis show a linear dose relationship. From the detailed study of normal, abnormal phases of prophase, metaphase, anaphase and telophase, it is observed that the abnormality (per cent) in all stages of mitosis has increased with increase in dose. Under different doses, the observed characters of abnormality in chromosomes of Lathyrus sativus may exhibit the occurence of direct hit process. (M.N.)

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

Energy Technology Data Exchange (ETDEWEB)

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.

Telomere Length in Circulating Lymphocytes: Association with Chromosomal Aberrations

Czech Academy of Sciences Publication Activity Database

Hemminki, K.; Rachakonda, S.; Musak, L.; Vymetálková, Veronika; Halasová, E.; Forsti,, A.; Vodičková, Ludmila; Buchancová, J.; Vodička, Pavel; Kumar, R.

2015-01-01

Roč. 54, č. 3 (2015), s. 194-196 ISSN 1045-2257 Institutional support: RVO:68378041 Keywords : structural chromosome aberrations * healthy subjects * relative telomere length * genotoxicity * telomere biology Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.960, year: 2015

Retrospective dosimetry using chromosome painting

International Nuclear Information System (INIS)

Nasazzi, N.B.; Giorgio, M.D.; Taja, M.R.

2000-01-01

Chromosome aberration frequency measured in peripheral lymphocytes of persons exposed to ionizing radiation has been used since 1960s for dose assessment. Suspected overexposure is usually evaluated by the frequency of dicentrics and centric rings using an appropriate in vitro calibration curve. However, these chromosome aberrations are unstable with time after exposure and dose reconstruction may encounter uncertainties when the time between the exposure and the analysis is considerable or even unknown. It appears that translocations persist with time after exposure and may be used as an indication of acute past overexposures. Moreover, they appear to accumulate the cytogenetical information, which correlates with the dose received under fractionated, chronic or even occupational exposure conditions. Translocations may be detected using G-banding, which allows to score the total amount of radiation induced translocations but it is a time consuming method, or by Chromosome Painting, a method base on the Fluorescence in situ Hybridization (FISH) technique, painting only some chromosome pairs with specific whole chromosome probes and then extrapolating the observed translocation frequencies to the full genome. The latter method allows a faster aberration scoring than G-banding and appears to be the most promissory tool for biodosimetry, particularly when it is necessary to assess low doses and consequently to score a large number of metaphases, e.g. radiation workers exposed within dose limits. As with the unstable chromosome aberration, it is necessary an in vitro calibration curve based on the frequency of stable chromosome aberrations to assess doses. Our laboratory performed calibration curves for Co 60 γ-rays based on the frequencies of unstable (dicentrics and centric rings detected by conventional Giemsa staining) and stable chromosome aberrations (translocations and inversions, detected by G-banding). In order to minimize the interlaboratory variability, we

Chromosomal sensitivity to X-rays in lymphocytes from patients with Turner syndrome

International Nuclear Information System (INIS)

Heras, J.G.; Coco, R.

1986-01-01

Lymphocytes from patients with Turner syndrome were irradiated with X-rays to determine the chromosomal aberration frequency in first-division metaphases. Five patients with 45,X karyotype; three 45,X/46,Xi(X)q mosaics; one 45,X/47,XXX mosaic and 9 female controls were studied. Patients with a 45,X karyotype exhibited a radioinduced chromosomal aberration frequency similar to controls. In the mosaics, 45,X cells has a mean frequency of 38.75 +- 2.16; 46,Xi(X)q cells a mean of 38 +- 2.16 and the control group a rate of 36.25 +- 4.32. No differences were observed between 45,X and 46,Xi(X)q cells, 45,X and normal cells or 46,Xi(X)q and normal cells. Apparently neither the X monosomy nor the Xq isochromosome influences the 'in vitro' X-ray-induced chromosomal damage in Turner syndrome lymphocytes. (Auth.)

Chromosomal mosaicism in mouse two-cell embryos after paternal exposure to acrylamide

Energy Technology Data Exchange (ETDEWEB)

Marchetti, Francesco; Bishop, Jack; Lowe, Xiu; Wyrobek, Andrew J

2008-10-14

Chromosomal mosaicism in human preimplantation embryos is a common cause ofspontaneous abortions, however, our knowledge of its etiology is limited. We used multicolor fluorescence in situ hybridization (FISH) painting to investigate whether paternally-transmitted chromosomal aberrations result in mosaicism in mouse 2-cell embryos. Paternal exposure to acrylamide, an important industrial chemical also found in tobacco smoke and generated during the cooking process of starchy foods, produced significant increases in chromosomally defective 2-cell embryos, however, the effects were transient primarily affecting the postmeiotic stages of spermatogenesis. Comparisons with our previous study of zygotes demonstrated similar frequencies of chromosomally abnormal zygotes and 2-cell embryos suggesting that there was no apparent selection against numerical or structural chromosomal aberrations. However, the majority of affected 2-cell embryos were mosaics showing different chromosomal abnormalities in the two blastomeric metaphases. Analyses of chromosomal aberrations in zygotes and 2-cell embryos showed a tendency for loss of acentric fragments during the first mitotic division ofembryogenesis, while both dicentrics and translocations apparently underwent propersegregation. These results suggest that embryonic development can proceed up to the end of the second cell cycle of development in the presence of abnormal paternal chromosomes and that even dicentrics can persist through cell division. The high incidence of chromosomally mosaic 2-cell embryos suggests that the first mitotic division of embryogenesis is prone to missegregation errors and that paternally-transmitted chromosomal abnromalities increase the risk of missegregation leading to embryonic mosaicism.

Computational model of dose response for low-LET-induced complex chromosomal aberrations

International Nuclear Information System (INIS)

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

2015-01-01

Experiments with full-colour mFISH chromosome painting have revealed high yield of radiation-induced complex chromosomal aberrations (CAs). The ratio of complex to simple aberrations is dependent on cell type and linear energy transfer. Theoretical analysis has demonstrated that the mechanism of CA formation as a result of interaction between lesions at a surface of chromosome territories does not explain high complexes-to-simples ratio in human lymphocytes. The possible origin of high yields of γ-induced complex CAs was investigated in the present work by computer simulation. CAs were studied on the basis of chromosome structure and dynamics modelling and the hypothesis of CA formation on nuclear centres. The spatial organisation of all chromosomes in a human interphase nucleus was predicted by simulation of mitosis-to-interphase chromosome structure transition. Two scenarios of CA formation were analysed, 'static' (existing in a nucleus prior to irradiation) centres and 'dynamic' (formed in response to irradiation) centres. The modelling results reveal that under certain conditions, both scenarios explain quantitatively the dose-response relationships for both simple and complex γ-induced inter-chromosomal exchanges observed by mFISH chromosome painting in the first post-irradiation mitosis in human lymphocytes. (authors)

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

Directory of Open Access Journals (Sweden)

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. 

Structural Chromosomal Alterations Induced by Dietary Bioflavonoids in Fanconi Anemia Lymphocytes

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Gonzalo Guevara

2007-06-01

Full Text Available IntroductionFanconi anemia is an autosomal recessive diseasecharacterized by a variety of congenital abnormalities,progressive bone marrow failure,increased chromosomal instability and higherrisk to acute myeloid leukemia, solid tumors. Thisentity can be considered an appropriate biologicalmodel to analyze natural substances with possiblegenotoxic effect. The aims of this study wereto describe and quantify structural chromosomalaberrations induced by 5 flavones, 2 isoflavonesand a topoisomerase II chemotherapeutic inhibitorin Fanconi anemia lymphocytes in order todetermine chromosomal numbers changes and/or type of chromosomal damage.Materials and methodsChromosomes stimulated by phytohaemagglutininM, from Fanconi anemia lymphocytes,were analysed by conventional cytogenetic culture.For each chemical substance and controls,one hundred metaphases were evaluated. Chromosomalalterations were documented by photographyand imaging analyzer. To statisticalanalysis was used chi square test to identify significantdifferences between frequencies of chromosomaldamage of basal and exposed cellcultured a P value less than 0.05.ResultsThere were 431 chromosomal alterations in1000 metaphases analysed; genistein was themore genotoxic bioflavonoid, followed in descendentorder by genistin, fisetin, kaempferol,quercetin, baicalein and miricetin. Chromosomalaberrations observed were: chromatidbreaks, chromosomal breaks, cromatid andchromosomal gaps, quadriratials exchanges,dicentrics chromosome and complex rearrangements.ConclusionBioflavonoids as genistein, genistin and fisetin,which are commonly present in the human diet,showed statistical significance in the number ofchromosomal aberrations in Fanconi anemialymphocytes, regarding the basal damage.

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

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)

FahamecV1:A Low Cost Automated Metaphase Detection System

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H. Yilmaz

2017-12-01

Full Text Available In this study, FahamecV1 is introduced and investigated as a low cost and high accuracy solution for metaphase detection. Chromosome analysis is performed at the metaphase stage and high accuracy and automated detection of the metaphase stage plays an active role in decreasing analysis time. FahamecV1 includes an optic microscope, a motorized microscope stage, an electronic control unit, a camera, a computer and a software application. Printing components of the motorized microscope stage (using a 3D printer is of the main reasons for cost reduction. Operations such as stepper motor calibration, are detection, focusing, scanning, metaphase detection and saving of coordinates into a database are automatically performed. To detect metaphases, a filter named Metafilter is developed and applied. Average scanning time per preparate is 77 sec/cm2. True positive rate is calculated as 95.1%, true negative rate is calculated as 99.0% and accuracy is calculated as 98.8%.

Chromosomal aberrations in tire plant workers and interaction with

Czech Academy of Sciences Publication Activity Database

Musak, L.; Souček, P.; Vodičková, Ludmila; Naccarati, Alessio; Halasová, E.; Poláková, Veronika; Slyšková, Jana; Susová, S.; Buchancová, J.; Šmerhovský, Z.; Sediková, J.; Klimentová, G.; Osina, O.; Hemminki, K.; Vodička, Pavel

2008-01-01

Roč. 641, 1-2 (2008), s. 36-42 ISSN 0027-5107 R&D Projects: GA MZd NR8563 Institutional research plan: CEZ:AV0Z50390512 Keywords : Chromosomal aberrations * Genetic polymorphisms * DNA repair genes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.198, year: 2008

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

Chromosome aberrations and rogue cells in lymphocytes of Chernobyl clean-up workers

International Nuclear Information System (INIS)

Lazutka, J.R.

1996-01-01

A cytogenetic analysis was performed on peripheral blood lymphocytes from 183 Chernobyl clean-up workers and 27 control individuals. Increased frequencies of chromosome aberrations were associated with exposure to radiation at Chernobyl, alcohol abuse and a history of recent influenza infection. However, only approximately 20% of Chernobyl clean-up workers had an increased frequency of dicentric and ring chromosomes. At the same time, an increased frequency of acentric fragments in lymphocytes of clean-up workers was characteristic. The use of multivitamins as dietary supplement significantly decreased the frequency of chromosome aberrations, especially of chromatid breaks. Rogue cells were found in lymphocytes of 28 clean-up workers and 3 control individuals. The appearance of rogue cells was associated with a recent history of acute respiratory disease (presumably caused by adenoviral infection) and, probably, alcohol abuse. Dicentric chromosomes in rogue cells were distributed according to a negative binomial distribution. Occurrence of rogue cells due to a perturbation of cell cycle control and abnormal apoptosis is suggested

Spectrum of chromosomal aberrations in peripheral lymphocytes of hospital workers occupationally exposed to low doses of ionizing radiation

International Nuclear Information System (INIS)

Maffei, Francesca; Angelini, Sabrina; Forti, Giorgio Cantelli; Violante, Francesco S.; Lodi, Vittorio; Mattioli, Stefano; Hrelia, Patrizia

2004-01-01

Chromosome aberrations frequency was estimated in peripheral lymphocytes from hospital workers occupationally exposed to low levels of ionizing radiation and controls. Chromosome aberrations yield was analyzed by considering the effects of dose equivalent of ionizing radiation over time, and of confounding factors, such as age, gender and smoking status. Frequencies of aberrant cells and chromosome breaks were higher in exposed workers than in controls (P=0.007, and P=0.001, respectively). Seven dicentric aberrations were detected in the exposed group and only three in controls, but the mean frequencies were not significantly different. The dose equivalent to whole body of ionizing radiation (Hwb) did appear to influence the spectrum of chromosomal aberrations when the exposed workers were subdivided by a cut off at 50 mSv. The frequencies of chromosome breaks in both subgroups of workers were significantly higher than in controls (≤50 mSv, P=0.041; >50 mSv, P=0.018). On the other hand, the frequency of chromatid breaks observed in workers with Hwb >50 mSv was significantly higher than in controls (P=0.015) or workers with Hwb ≤50 mSv (P=0.046). Regarding the influence of confounding factors on genetic damage, smoking status and female gender seem to influence the increase in chromosome aberration frequencies in the study population. Overall, these results suggested that chromosome breaks might provide a good marker for assessing genetic damage in populations exposed to low levels of ionizing radiation

Chromosomal aberrations found in Paracalanus aculeatus (Giesbrecht) at the time of solar eclipse

Digital Repository Service at National Institute of Oceanography (India)

Goswami, U.; Goswami, S.C.

Chromosomal aberrations in the form of an unequal heteromorphic homologous pair and a supernumerary chromosome were observed in the gonad of a copepod - @iParacalanus aculeatus@@ after being exposed to the total solar eclipse of Feb. 16, 1980...

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)

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

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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

Chromosomal sensitivity to X-rays in lymphocytes from patients with Turner syndrome

Energy Technology Data Exchange (ETDEWEB)

Heras, J G; Coco, R

1986-03-01

Lymphocytes from patients with Turner syndrome were irradiated with X-rays to determine the chromosomal aberration frequency in first-division metaphases. Five patients with 45,X karyotype; three 45,X/46,Xi(X)q mosaics; one 45,X/47,XXX mosaic and 9 female controls were studied. Patients with a 45,X karyotype exhibited a radioinduced chromosomal aberration frequency similar to controls. In the mosaics, 45,X cells has a mean frequency of 38.75 +- 2.16; 46,Xi(X)q cells a mean of 38 +- 2.16 and the control group a rate of 36.25 +- 4.32. No differences were observed between 45,X and 46,Xi(X)q cells, 45,X and normal cells or 46,Xi(X)q and normal cells. Apparently neither the X monosomy nor the Xq isochromosome influences the in vitro X-ray-induced chromosomal damage in Turner syndrome lymphocytes. (Auth.). 29 references, 4 tables.

Unstable chromosome aberrations on peripheral blood lymphocytes from patients with cervical uterine cancer following radiotherapy

International Nuclear Information System (INIS)

Magnata, Simey de Souza Leao Pereira

2002-09-01

Absorbed dose determination is an important step for risk assessment related to an exposure to ionizing radiation. However, physical dosimetry cannot be always performed, principally in the case of retrospective estimates. In this context, the use of bioindicators (biological effects) has been proposed, which defines the so-called biological dosimetry. In particular, scoring of unstable chromosomes aberrations (dicentrics, centric rings and fragments) of peripheral blood lymphocytes, while is the most reliable biological method for estimating individual exposure to ionizing radiation. In this work, blood samples from 5 patients, with cervical uterine cancer, were evaluated after partial-body radiotherapy with a source of 69 Co. For this, conventional cytogenetic method was employed, based on Giemsa coloration and fluorescence in situ hybridization, in order to correlate the frequency of unstable chromosome aberrations of blood lymphocytes with absorbed dose, as a result of the radiotherapy. A good agreement was observed between the frequency of chromosome aberrations scored and the values of dose previously calculated by physical dosimetry during patient's radiotherapy. The results presented in this work point out the importance of concerning analyses of unstable chromosome aberrations as biological dosimeter in the investigation of partial-body exposure to ionizing radiation. (author)

GTPase Ran strongly accumulates at the kinetochores of somatic chromosomes in the spermatogonial mitoses of Acricotopus lucidus (Diptera, Chironomidae).

Science.gov (United States)

Staiber, Wolfgang

2014-07-01

Unequal chromosome segregation and spindle formation occurs in the last gonial mitosis in the germ line of the chironomid Acricotopus lucidus. During this differential mitosis, all germ line-limited chromosomes (=Ks) migrate undivided to only one pole of the cell, while the somatic chromosomes (=Ss) first remain in the metaphase plane, and with the arrival of the Ks at the pole, they then separate equally. The evolutionarily conserved GTPase Ran plays a crucial role in many cellular processes. This includes the regulation of microtubule nucleation and stabilisation at kinetochores and of spindle assembly during mitosis, which is promoted by a RanGTP concentration gradient that forms around the mitotic chromosomes (Kalab et al. in Science 295:2452-2456, 2002, Nature 440:697-701, 2006). In the present study, a strong accumulation of Ran was detected by immunofluorescence at the kinetochores of the Ss in normal gonial and differential gonial mitoses of males of A. lucidus. In contrast, no Ran accumulation was observed at the kinetochores of the Ss in the metaphases of brain ganglia mitoses or of aberrant spermatocytes or in metaphases I and II of spermatocyte meiotic divisions. Likewise, there was no accumulation at the kinetochores of Drosophila melanogaster mitotic chromosomes from larval brains. The specific accumulation of Ran at the kinetochores of the Ss in differential gonial mitoses of A. lucidus strongly suggests that Ran is involved in a mechanism acting in this exceptional mitosis, which retains the Ss at the metaphase plane and prevents a premature separation and unequal segregation of the Ss during monopolar migration of the Ks.

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)

The use of unstable chromosome aberrations and micronuclei in the individual biomonitoring: a comparative study

International Nuclear Information System (INIS)

Fernandes, Thiago de Salazar e

2005-02-01

Biodosimetry is based on the investigation of radioinduced biological effects in order to correlate them with the absorbed dose. The quantification of unstable chromosome aberrations and micronuclei, in peripheral blood lymphocytes, are two methods commonly used in biodosimetry. In this context, the aim of this research was to compare these methods in the biomonitoring of health care professionals occupationally exposed to ionizing radiation. In parallel, the technique of C-banding was evaluated for quality control of unstable chromosome aberrations analyses. Thus, samples of peripheral blood from health care professionals of three hospitals from Recife (Brazil) were collected, and the lymphocytes cultures were carried out based on the cytogenetic classical technique. It was pointed out that analysis of micronuclei is faster than the unstable chromosome aberrations ones, which suggests the use of the former in preliminary evaluation in cases of suspected accidental exposure. C-banding technique was efficient, as confirmatory test, in the identification of dicentrics and rings during the analyses of unstable chromosome aberrations, being able to be applied in the quality control in biodosimetry. The comparison between the individual work conditions with the frequencies of unstable aberrations and micronuclei obtained from cytogenetic analysis, resulted in the change of behavior of the professionals involved in this research, with a better observance of the radioprotection standards. (author)

Conventional radiation-biological dosimetry using frequencies of unstable chromosome aberrations

International Nuclear Information System (INIS)

Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S.

1998-01-01

Frequency of chromosome aberrations detected by conventional cytogenetics is a very useful parameter in biological radiodosimetry. It can be used for estimating absorbed doses in individuals working with radioactive sources and individuals accidentally exposed to radiation. In the first case subjects wear physical dosimeters as a routine safety habit. The laboratory at the Institute of Radioprotection and Dosimetry (IRD, Brazil) has been using conventional cytogenetic analysis to complement data obtained by physical dosimetry since 1983. Until now, more than one hundred cases were investigated where individual physical dosimeters detected occupational exposure (above the safety limits allowed). In total, only 34% of these cases were confirmed by conventional cytogenetic dosimetry. Also, conventional cytogenetic analysis following the radiation accident of Goiania (Brazil) in 1987 have been used. Peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequencies of unstable chromosomal aberrations (dicentrics, centric rings and acentrics fragments) to estimate absorbed radiation doses. During the emergency period, doses were estimated to help immediate medical treatment using in vitro calibration curves produced before the accident. Later on, doses were assessed once more using new in vitro calibration curves. A drawback of this technique is that unstable aberrations are lost after exposure. To investigate the mean lifespan of lymphocytes containing dicentric and ring aberrations, we have followed 15 victims of the Goiania accident over all these years. Results suggest that the disappearance of unstable aberrations is dose-dependent. This could explain the variation in the results found among studies in this field

Conventional radiation-biological dosimetry using frequencies of unstable chromosome aberrations

Energy Technology Data Exchange (ETDEWEB)

Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S. [Institute of Radioprotection and Dosimetry (IRD), National Commission of Nuclear Energy (CNEN), Av. Salvador Allende, Cx. P. 37750, Rio de Janeiro 22.780-160 (Brazil)

1998-08-03

Frequency of chromosome aberrations detected by conventional cytogenetics is a very useful parameter in biological radiodosimetry. It can be used for estimating absorbed doses in individuals working with radioactive sources and individuals accidentally exposed to radiation. In the first case subjects wear physical dosimeters as a routine safety habit. The laboratory at the Institute of Radioprotection and Dosimetry (IRD, Brazil) has been using conventional cytogenetic analysis to complement data obtained by physical dosimetry since 1983. Until now, more than one hundred cases were investigated where individual physical dosimeters detected occupational exposure (above the safety limits allowed). In total, only 34% of these cases were confirmed by conventional cytogenetic dosimetry. Also, conventional cytogenetic analysis following the radiation accident of Goiania (Brazil) in 1987 have been used. Peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequencies of unstable chromosomal aberrations (dicentrics, centric rings and acentrics fragments) to estimate absorbed radiation doses. During the emergency period, doses were estimated to help immediate medical treatment using in vitro calibration curves produced before the accident. Later on, doses were assessed once more using new in vitro calibration curves. A drawback of this technique is that unstable aberrations are lost after exposure. To investigate the mean lifespan of lymphocytes containing dicentric and ring aberrations, we have followed 15 victims of the Goiania accident over all these years. Results suggest that the disappearance of unstable aberrations is dose-dependent. This could explain the variation in the results found among studies in this field

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).

Chromosomal instability and double minute chromosomes in a breast cancer patient

International Nuclear Information System (INIS)

Lalic, H.; Radosevic-Stasic, B.

2004-01-01

Cytogenetic analysis was performed in peripheral blood lymphocytes (PBL) of a woman with ductal breast carcinoma, who as a hospital employee was exposed professionally for 15 years to low doses of ionizing radiation. The most important finding after the chemotherapy in combination with radiotherapy was the presence of double minutes (DM) chromosomes, in combination with other chromosomal abnormalities (on 200 scored metaphases were found 2 chromatid breaks, 10 dicentrics, 11 acentric fragments, 2 gaps, and 3 double min chromosomes). In a repeated analysis (after 6 months), DM chromosomes were still present. To rule out the possibility that the patient was overexposed to ionizing radiation at work, her blood test was compared with a group of coworkers as well as with a group of professionally unexposed people. The data rejected this possibility, but the retroactive analysis showed that the patient even at the time of employment had a moderately increased number of chromosomal aberrations (3.5%) consisting of 3 isochromatids and 4 gaps, suggesting that her initial genomic instability enhanced the later development. The finding of a continuous presence of rare DM chromosomes in her PBL (4 and 10 months after radio-chemotherapy) was considered as an indicator of additional risk, which might have some prognostic significance. (author)

γ-ray induced chromosome aberration in rabbit peripheral blood lymphocytes irradiated in partial and whole body and decline of aberration rate with time post-exposure

International Nuclear Information System (INIS)

Zhang Lianzhen; Deng Zhicheng; Wang Haiyan

1997-01-01

Te author presents the results of study on 60 Co γ-ray induced chromosome aberration in rabbits peripheral blood lymphocytes irradiated in partial and whole body and the aberration rate decrease with the time of post-exposure. The experiments included 5 groups, it was whole-body exposure group, partial-body exposure (abdomen and pelvic cavity) group, blood irradiation group in vitro and control group respectively. Radiation dose was 3.0 Gy delivered at rate of 0.5 Gy/min. The results show that it was no significant differences between whole body and in blood irradiation group. The chromosome aberration yield in whole body exposure group was higher than that in partial-body group and in the abdomen exposure group was higher than in that in the pelvic cavity irradiation; The chromosome aberration rate decreased with the time of post-exposure in partial and whole body by γ-ray irradiation

[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.

A quantitative study of the second meiotic metaphase in male mice (Mus musculus).

Science.gov (United States)

Beatty, R A; Lim, M C; Coulter, V J

1975-01-01

Over 11,000 second meiotic metaphase spreads stained for the pericentromeric region have been studied quantitatively in male mice of 14 strains. The sex-chromosome constitution of a cell could be judged objectively if X and Y chromosomes and ploidy were all scored. A bias arose if only Y chromosomes and ploidy were scored but could be corrected statistically. There was no sign of other forms of bias. The original contiguity of X and Y second metaphases in vivo was very occasionally evident in the preparations. Most of the subhaploid aneuploid counts were assumed to be artifactual. The incidence of truly aneuploid second metaphases in 13 strains was estimated as 0.38+/-0.12%. The estimated average rate per chromosome was 0.019+/-0.006%, with a comparable order of magnitude for the sex chromosomes alone. Simultaneous aneuploidy of two or more chromosomes of the haploid set was estimated to be very rare. Of the spreads from 13 strains, 9.6% were polyploid (2N, 3N, 4N) and showed most of the possible combinations of sex chromosomes. Nearly all the polyploid spreads were considered to arise by artifactual cell fusion at the time of second metaphase during the preparative technique, especially of the X and Y daughter-cell products of the first meiotic division. Other modes of origin (true polyploidy, accidental superposition of cells during preparation) were unlikely. The data could be accommodated by a statistical model with only four parameters. It allowed for artifactual fusion mainly between daughter cells but also between non-daughter cells, bias in one scoring method, and bias in the numbers of cells with given ploidy successfully mounted. Current techniques of chromosome preparation were thought to be wholly unsuitable for the recognition of true polyploidy. The artifactual origin of polyploid spreads was borne out by an absence of polyploid spermatozoa in 14 strains. There appeared to be a virtually constant transmission rate of paternal X and Y chromosomes from

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

Expression of a possible constitutional hot spot in sperm chromosomes of a patient treated for Wilms' tumor

International Nuclear Information System (INIS)

Genesca, A.; Miro, R.; Caballin, M.R.; Benet, J.; Navarro, J.; Templado, C.; Bonfill, X.; Egozcue, J.

1987-01-01

Sperm chromosomes were studied in a man who was treated for Wilms' tumor with radiotherapy (RT) and chemotherapy (CT) 18 years ago. Human pronuclear sperm chromosomes were obtained after penetration of zona-free hamster eggs. Eighty-nine sperm chromosome complements were analyzed; 12.4% of them showed structural anomalies. This percentage was statistically different from the one found in our laboratory for controls (p less than 0.05). Five of eleven structurally abnormal metaphases had the same aberration: fission of chromosome number1 with the breakpoint at or near the centromere. Breaks and rearrangements of chromosome number1, often involving the centromere region, are among the most frequent anomalies found in Wilms' tumor cells

[Prevalence of chromosomal aberrations at birth in the Clinical Hospital of Universidad de Chile, 1990-2001].

Science.gov (United States)

Nazer, Julio; Antolini, Mónica; Juárez, María Eugenia; Cifuentes, Lucía; Hubner, María Eugenia; Pardo, Andrea; Castillo, Silvia

2003-06-01

A cytogenetical study should be performed to every newborn with malformations. If a chromosomal aberration is found, parents must be studied to give an adequate genetic advise. To study the frequency of chromosomal aberrations in newborns with malformations. In the Clinical Hospital of the University of Chile all malformations in newborns are registered, as part of the Collaborative Latin American Study of Congenital Malformations (ECLAMC). The frequency of chromosomal aberrations, determined by cytogenetical studies, was determined in newborns with malformations. In the study period, there were 32,214 births. Of these, 2,268 live newborns and 43 stillbirths had malformations. Ninety nine children with malformations had chromosomal aberrations (4.3%). Trisomy 21 was the most common aberration with a rate of 23/10,000 births, followed by trisomy 18 with a rate of 4/10,000 and trisomy 18 with a rate of 1.2/10,000. Ninety four percent of these children were born alive and 16.1% died before discharge from the hospital. The masculinity indexes for Down syndrome and for trisomy 18 were 0.38 and 0.61 respectively. A higher frequency of female gender for trisomy 21 and male gender for trisomy 18 has not been reported previously.

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

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.

The relationship between radiation load and chromosome aberrations in permanent staff of nuclear facilities

International Nuclear Information System (INIS)

Heubisch, W.

1982-01-01

Employees of nuclear power stations can be exposed to an increased risk. Using chromosome analytical methods an attempt is made to establish a dose-response relationship for relatively low radiation dose levels. Chromosome aberrations in lymphocytes at the stage of mitosis were classified according to morphological structure and gaps. Correlation and regression analysis produced a positive relationship compared to the previous year's dose and aberrations, whereas no dependence could be proved for the actual age dose and age. (DG) [de

The Project Of Another Low-Cost Metaphase Finder

International Nuclear Information System (INIS)

Furukawa, Akira

2016-01-01

The most popular and 'gold standard' phenomenon in Biological dosimetry is the appearance of dicentric chromosomes in metaphase in white blood cells. The metaphase finder is a tool for biological dosimetry that finds metaphase cells on slide glasses. The author and a software company were using new special software that was faster than conventional systems. A Nikon Eclipse Ni-E microscope with motorised X-Y stage, 4x objective lens and 1920 x 1024 pixels colour camera for hardware were used. The software uses mathematical morphology filters. The new system was compact and low-priced. And the remarkable point is, this system can be applicable not only to human blood, but also to non-human samples. The speed was 208-236 s per 5 x 20 mm area, while capturing 378 images, which achieved the aim of the project. The false-positive ratio achieved below 5% in some slides. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

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

Disruption of Maternal DNA Repair Increases Sperm-DerivedChromosomal Aberrations

Energy Technology Data Exchange (ETDEWEB)

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.

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

Chromosome damage in Chinese hamster cells produced by 125I-UdR at the site of its incorporation

International Nuclear Information System (INIS)

Hughes, W.L.; Weinblatt, A.C.; Prensky, W.

1978-01-01

Metaphase chromosomal aberrations were produced by 125 I-labeled iododeoxyuridine ( 125 I-UdR) incorporated into Chinese hamster Don cells at the end of the S-period of the cell cycle. Chromosome damage and the number of autoradiographic silver grains were recorded for whole cells, for chromosome pairs 4 and 5 and for the X and the Y chromosomes. The X and the Y chromosomes, which label late in S, were at least twice as heavily labeled as chromosome pairs 4 and 5 - two readily recognizable autosomes of similar size. The incidence of chromosome damage was at least six times that which would have been expected from equivalent doses of X-rays and the incidence of damage was directly related to the number of silver grains over each chromosome. It is estimated that it takes four to ten disintegrations to produce a visible chromosome aberration. The finding that chromosome damage is localized at the site of the 125 I decay is most readily explained by the high flux of low energy Auger electrons occurring at the site of the decay of the incorporated 125 I atom. (Auth.)

Chromosome investigations on persons whose mothers have been treated with ionizing radiations during pregnancy

International Nuclear Information System (INIS)

Hanebuth, P.

1982-01-01

This thesis reports on chromosome investigations on seven persons between 2 and 26 years of age who, during their prenatal life, have been exposed to ionizing radiation. The metaphase chromosomes from peripheral lymphocytes, obtained by standard cytogenic methods, have been scanned for numerical and structural aberrations after a culture period of two or three days. Comparison with non-irradiated specimens revealed a summarily slight increase in the occurrence of some structural aberrations in the irradiated material. The differences are smaller in number than the rate of deviation to be accounted to culturing techniques so that one cannot deduce a radiation-induced impairment from these results. As one of the persons investigated has been undergoing longterm therapy with anticonvulsive drugs, this case is discussed separately. In another case, new staining methods (G, C, or Q-bands) together with an investigation of material from the father, revealed a particularly small Y-chromosome. (orig./MG) [de

Chromosomal aberrations and deoxyribonucleic acid single-strand breaks in adipose-derived stem cells during long-term expansion in vitro.

Science.gov (United States)

Froelich, Katrin; Mickler, Johannes; Steusloff, Gudrun; Technau, Antje; Ramos Tirado, Mario; Scherzed, Agmal; Hackenberg, Stephan; Radeloff, Andreas; Hagen, Rudolf; Kleinsasser, Norbert

2013-07-01

Adipose-derived stem cells (ASCs) are a promising mesenchymal cell source for tissue engineering approaches. To obtain an adequate cell amount, in vitro expansion of the cells may be required in some cases. To monitor potential contraindications for therapeutic applications in humans, DNA strand breaks and chromosomal aberrations in ASCs during in vitro expansion were examined. After isolation of ASC from human lipoaspirates of seven patients, in vitro expansion over 10 passages was performed. Cells from passages 1, 2, 3, 5 and 10 were used for the alkaline single-cell microgel electrophoresis (comet) assay to detect DNA single-strand breaks and alkali labile as well as incomplete excision repair sites. Chromosomal changes were examined by means of the chromosomal aberration test. During in vitro expansion, ASC showed no DNA single-strand breaks in the comet assay. With the chromosomal aberration test, however, a significant increase in chromosomal aberrations were detected. The study showed that although no DNA fragmentation could be determined, the safety of ASC cannot be ensured with respect to chromosome stability during in vitro expansion. Thus, reliable analyses for detecting ASC populations, which accumulate chromosomal aberrations or even undergo malignant transformation during extensive in vitro expansion, must be implemented as part of the safety evaluation of these cells for stem cell-based therapy. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Biological dosimetry of ionizing radiation by chromosomal aberration analysis

International Nuclear Information System (INIS)

Gonzalez-Castano, S.; Silva, A.; Navlet, J.

1990-01-01

Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y =α + β 1 D + β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs

Biological dosimetry of ionizing radiation by chromosomal aberration analysis

International Nuclear Information System (INIS)

Navlet Armenta, J.M.; Gonzalez, S.; Silva, A.

1990-01-01

Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haemathological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study of chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 o C has been produced. Experimental data is fitted to model Y = α+β 1 D+β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (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.

Cytogenetic heterogeneity and their serial dynamic changes during acquisition of cytogenetic aberrations in cultured mesenchymal stem cells

Energy Technology Data Exchange (ETDEWEB)

Kim, Jung-Ah [Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Im, Kyong Ok; Park, Si Nae; Kwon, Ji Seok [Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Seon Young [Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Oh, Keunhee; Lee, Dong-Sup [Laboratory of Immunology and Cancer Biology, Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul (Korea, Republic of); Transplantation Research Institute, Seoul National University College of Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Min Kyung; Kim, Seong Who [Department of Biochemistry and Molecular Biology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Jang, Mi; Lee, Gene [Lab of Molecular Genetics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul (Korea, Republic of); Oh, Yeon-Mok; Lee, Sang Do [Department of Pulmonary and Critical Care Medicine, Asthma Center and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Dong Soon, E-mail: soonlee@snu.ac.kr [Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2015-07-15

Highlights: • We evaluated cytogenetic aberrations of MSC during culture using G-banding and FISH. • We tracked the quantitative changes of each clone among heterogeneity upon passages. • The changes of cytogenetic profile upon passages were similar to cancer stem cell. - Abstract: To minimize the risk of tumorigenesis in mesenchymal stem cells (MSCs), G-banding analysis is widely used to detect chromosomal aberrations in MSCs. However, a critical limitation of G-banding is that it only reflects the status of metaphase cells, which can represent as few as 0.01% of tested cells. During routine cytogenetic testing in MSCs, we often detect chromosomal aberrations in minor cell populations. Therefore, we aimed to investigate whether such a minority of cells can expand over time or if they ultimately disappear during MSC passaging. We passaged MSCs serially while monitoring quantitative changes for each aberrant clone among heterogeneous MSCs. To investigate the cytogenetic status of interphase cells, which represent the main population, we also performed interphase FISH analysis, in combination with G-banding and telomere length determination. In human adipose tissue-derived MSCs, 4 types of chromosomal aberrations were found during culturing, and in umbilical cord MSCs, 2 types of chromosomal aberrations were observed. Sequential dynamic changes among heterogeneous aberrant clones during passaging were similar to the dynamic changes observed in cancer stem cells during disease progression. Throughout all passages, the quantitative G-banding results were inconsistent with those of the interphase FISH analysis. Interphase FISH revealed hidden aberrations in stem cell populations with normal karyotypes by G-banding analysis. We found that telomere length gradually decreased during passaging until the point at which cytogenetic aberrations appeared. The present study demonstrates that rare aberrant clones at earlier passages can become predominant clones during

Cytogenetic heterogeneity and their serial dynamic changes during acquisition of cytogenetic aberrations in cultured mesenchymal stem cells

International Nuclear Information System (INIS)

Kim, Jung-Ah; Im, Kyong Ok; Park, Si Nae; Kwon, Ji Seok; Kim, Seon Young; Oh, Keunhee; Lee, Dong-Sup; Kim, Min Kyung; Kim, Seong Who; Jang, Mi; Lee, Gene; Oh, Yeon-Mok; Lee, Sang Do; Lee, Dong Soon

2015-01-01

Highlights: • We evaluated cytogenetic aberrations of MSC during culture using G-banding and FISH. • We tracked the quantitative changes of each clone among heterogeneity upon passages. • The changes of cytogenetic profile upon passages were similar to cancer stem cell. - Abstract: To minimize the risk of tumorigenesis in mesenchymal stem cells (MSCs), G-banding analysis is widely used to detect chromosomal aberrations in MSCs. However, a critical limitation of G-banding is that it only reflects the status of metaphase cells, which can represent as few as 0.01% of tested cells. During routine cytogenetic testing in MSCs, we often detect chromosomal aberrations in minor cell populations. Therefore, we aimed to investigate whether such a minority of cells can expand over time or if they ultimately disappear during MSC passaging. We passaged MSCs serially while monitoring quantitative changes for each aberrant clone among heterogeneous MSCs. To investigate the cytogenetic status of interphase cells, which represent the main population, we also performed interphase FISH analysis, in combination with G-banding and telomere length determination. In human adipose tissue-derived MSCs, 4 types of chromosomal aberrations were found during culturing, and in umbilical cord MSCs, 2 types of chromosomal aberrations were observed. Sequential dynamic changes among heterogeneous aberrant clones during passaging were similar to the dynamic changes observed in cancer stem cells during disease progression. Throughout all passages, the quantitative G-banding results were inconsistent with those of the interphase FISH analysis. Interphase FISH revealed hidden aberrations in stem cell populations with normal karyotypes by G-banding analysis. We found that telomere length gradually decreased during passaging until the point at which cytogenetic aberrations appeared. The present study demonstrates that rare aberrant clones at earlier passages can become predominant clones during

Chromosome Aberrations of East Asian Bullfrog (Hoplobatrachus rugulosus around a Gold Mine Area with Arsenic Contamination

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Atidtaya Suttichaiya

2016-01-01

Full Text Available The objectives of this study are to investigate the chromosome aberrations of the East Asian Bullfrog (Hoplobatrachus rugulosus in the gold mine area compared to an unaffected area. Three H. rugulosus were collected, and chromosome aberrations were studied using bone marrow. The level of arsenic was measured in water, sediment and H. rugulosus samples. The average concentrations of arsenic in the water and sediment samples from the gold mine and unaffected areas were 0.03 ± 0.003 mg/l and not detected in water as well as 351.59 ± 5.73 and 1.37 ± 1.07 mg/kg in sediment, respectively. The gold mine values were higher than the permissible limit of the water and soil quality standards, but the arsenic concentrations in the samples from the unaffected area were within prescribed limit. The average concentrations of arsenic in H. rugulosus samples from the gold mine and unaffected areas were 0.39 ± 0.30 and 0.07 ± 0.01 mg/kg, respectively, which were both lower than the standard of arsenic contamination in food. The diploid chromosome number of H. rugulosus in both areas was 2n=26, and the percentage of chromosome breakages of H. rugulosus in the gold mine area were higher than the unaffected area. There were eight types of chromosome aberrations, including a single chromatid gap, isochromatid gap, single chromatid break, isochromatid break, centric fragmentation, deletion, fragmentation and translocation. The most common chromosome aberration in the samples from the affected area was deletion. The difference in the percentage of chromosome breakages in H. rugulosus from both areas was statistically significant (p<0.05.

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

[THE INFLUENCE OF THE PREPARATION PRETREATMENT ON IN SITU DETECTION OF 5-METHYLCYTOSINE IN METAPHASE CHROMOSOMES AND IN INTERPHASE NUCLEI].

Science.gov (United States)

Grudinina, N A; Sasina, L K; Noniashvili, E M; Neronova, E G; Pavlinova, L I; Suchkova, I O; Sofronov, G A; Patkin, E L

2015-01-01

Qualitative and quantitate analysis of DNA methylation in situ at the level of cells, chromosomes and chromosomal domains is extremely important for the diagnosis and treatment of various diseases, the study of ageing and the consequences of environmental impacts. An important question arises, whether the revealed in situ methylation pattern reflects DNA methylation per se and (or) availability of the DNA for antibodies, which in turn depends on the peculiarities of chromatin structure and chromosome condensation. These events can lead to an incorrect evaluation of the actual pattern of DNA methylation. To avoid this shortcoming as far as possible, we have modified the most widely used method of revealing 5-methylcytosine in situ with monoclonal antibodies. Here we have shown that the detection of DNA methylation staining of chromosomes including C-heterochromatin, chromosomal arms and sister chromatids is drastically dependent on pretreatment of chromosomal preparations for immunocytochemical study using fluorescent antibodies. Using undifferentiated stem cells of mouse embryonal carcinoma line F9, it has been found that change in preparations storage results in a sharp fluorescence decrease up to complete disappearance of the signal in centromeric heterochromatin. With the help of the method described in the work, we have first revealed the asymmetry of sister chromatids methylation in metaphase chromosomes of F9 cell and lymphocytes of human periphery blood. This may lead to asymmetry of transcriptional signature of daughter cells after division. The proposed here modification of 5-methylcytosine detection in situ provides a more complete characterization of methylation of chromosomes and chromosomal domains, compared to previously published methods.

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)

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

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.

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

Energy Technology Data Exchange (ETDEWEB)

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.

Cyclin D1 splice site variant triggers chromosomal aberrations in healthy humans

Czech Academy of Sciences Publication Activity Database

Hemminki, K.; Mušák, L.; Vymetálková, Veronika; Šmerhovský, Z.; Halásová, E.; Osina, O.; Letková, L.; Försti, A.; Vodičková, Ludmila; Buchancová, J.; Vodička, Pavel

2014-01-01

Roč. 28, č. 3 (2014), s. 721-722 ISSN 0887-6924 Institutional support: RVO:68378041 Keywords : chromosomal aberrations * DNA repair Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 10.431, year: 2014

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)

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

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)

Statistical methods in regression and calibration analysis of chromosome aberration data

International Nuclear Information System (INIS)

Merkle, W.

1983-01-01

The method of iteratively reweighted least squares for the regression analysis of Poisson distributed chromosome aberration data is reviewed in the context of other fit procedures used in the cytogenetic literature. As an application of the resulting regression curves methods for calculating confidence intervals on dose from aberration yield are described and compared, and, for the linear quadratic model a confidence interval is given. Emphasis is placed on the rational interpretation and the limitations of various methods from a statistical point of view. (orig./MG)

Residual chromosomal damage after radiochemotherapy with and without amifostine detected by 24-color FISH

International Nuclear Information System (INIS)

Kuechler, A.; Wendt, T.G.; Dreidax, M.; Liehr, T.; Claussen, U.; Pigorsch, S.U.; Dunst, J.

2003-01-01

Background: Amifostine is a radioprotective drug applied to reduce acute radiation toxicity during a course of conventionally fractionated radiotherapy. In the present study, amifostine was used in patients undergoing adjuvant radiochemotherapy for rectal cancer. It was described previously that additional application of amifostine led to less acute skin and bowel toxicity. The present study was aimed to determine whether amifostine has an influence on the amount of residual chromosomal damage. Material and Methods: Peripheral lymphocytes of twelve rectal cancer patients who had undergone postoperative radiochemotherapy 2-3 years ago were investigated for residual chromosomal damage using 24-color fluorescence in situ hybridization (24-color FISH). All twelve patients had received a total dose of 55.8 Gy in conventional fractionation of 1.8 Gy and a 120-h continuous infusion of 5-fluorouracil (5-FU) chemotherapy (1,000 mg/m 2 per day) in the 1st and 5th week of irradiation. Seven out of twelve patients had been given additional amifostine on chemotherapy days (500 mg total dose as short i.v. infusion immediately prior to the daily radiation fraction). Cultivation of lymphocytes and 24-color FISH were performed according to standard protocols. 100 metaphases per patient were analyzed for chromosomal aberrations in a blind study. Results: Analysis of the average number of breaks per mitosis (B/M) revealed an increased amount of residual chromosomal damage in the group treated with amifostine (0.65 B/M [0.32-0.97]) as well as in those treated without amifostine (0.76 B/M [0.31-1.25]). Also the average number of cells containing aberrations per 100 analyzed metaphases was similar (with amifostine: 22.1 [13-32] vs. 24.4 [13-35] without amifostine). The aberration types, occurring as simple translocations, reciprocal translocations, breaks, dicentrics, inversions, rings and complex chromosomal rearrangements, did not show any specific accumulation in one or the other

FISHprep: A Novel Integrated Device for Metaphase FISH Sample Preparation

DEFF Research Database (Denmark)

Shah, Pranjul Jaykumar; Vedarethinam, Indumathi; Kwasny, Dorota

2011-01-01

We present a novel integrated device for preparing metaphase chromosomes spread slides (FISHprep). The quality of cytogenetic analysis from patient samples greatly relies on the efficiency of sample pre-treatment and/or slide preparation. In cytogenetic slide preparation, cell cultures...... are routinely used to process samples (for culture, arrest and fixation of cells) and/or to expand limited amount of samples (in case of prenatal diagnostics). Arguably, this expansion and other sample pretreatments form the longest part of the entire diagnostic protocols spanning over 3–4 days. We present here...... with minimal handling for metaphase FISH slide preparation....

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

Energy Technology Data Exchange (ETDEWEB)

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

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)

Oxidative stress and chromosomal aberrations in an environmentally exposed population

Czech Academy of Sciences Publication Activity Database

Rössner ml., Pavel; Rössnerová, Andrea; Šrám, Radim

2011-01-01

Roč. 707, 1-2 (2011), s. 34-41 ISSN 0027-5107 R&D Projects: GA MŽP(CZ) SP/1B3/8/08 Institutional research plan: CEZ:AV0Z50390512 Keywords : air pollution * oxidative stress * chromosomal aberrations Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.850, year: 2011

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)

Studies of chromosomal aberrations in occupationally coal exposed population (coal cutters)

International Nuclear Information System (INIS)

Vijender Reddy, V.; Rudrama Devi, K.

1995-01-01

A detailed study was carried out among the 235 coal mine workers (coal cutters) and 215 unexposed individuals (controls) on cytogenetic effect of coal in peripheral blood lymphocytes. The frequencies of chromosomal aberrations were studied in exposed coal mine workers as well as in the control groups . The confounding factors like smoking drinking and combination of both were taken into account. There was a significant increase in the total number of aberrations among exposed population subjected to different habits like smoking and alcoholism compared to that of the controls. (author). 14 refs., 1 tab

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)

An influence of occupational exposure on level of chromosome aberrations in nuclear power plant workers

International Nuclear Information System (INIS)

Birute Griciene; Grazina Slapsyte

2007-01-01

Complete text of publication follows. Objective. The workers of Ignalina Nuclear Power Plant (INPP) receive the highest occupational ionising radiation doses in Lithuania. Their occupational exposure results mainly from external low LET gamma radiation. Some workers receive additional internal and neutron exposure. Though exposure doses are generally low and don't exceed the annual dose limit, the higher doses are obtained during outages. The aim of the present study was to analyse chromosome aberration frequencies in lymphocytes of INPP workers exposed to the different types of ionising radiation. Methods. The blood sampling of 52 INPP male workers was performed in 2004-2006. For 29 workers radiation exposure resulted from the external gamma rays only. Their mean annual dose averaged over the 3-year period prior blood sampling was 11.7±8.7 mSv. The mean cumulative dose - 197.7±174.7 mSv. 15 workers had an intake of gamma radionuclides ( 60 Co, 137 Cs), contributing to the doses less than 0.1 mSv. Their mean cumulative dose - 278.2±191.9 mSv. The mean annual dose averaged over the 3-year period prior blood sampling was 11.8±5.3 mSv. For 8 subjects neutron doses below 0.2 mSv were recorded. Their mean annual dose averaged over the 3-year period prior blood sampling was 7.0±2.9 mSv. The mean cumulative dose was 241.8±93.0 mSv. Heparinized venous blood samples were taken and cultures were initiated according to the standard procedures. Phytohaemagglutinin (7.8 μg/ml) stimulated cultures were incubated at 37degC for 72 hours in RPMI 1640 medium supplemented with 12% heat-inactivated newborn calf serum, 40 μg/ml gentamycin. Colchicine was added to the culture during the initiation at a final concentration of 0,25 μg/ml. The harvested lymphocytes were treated with hypotonic KCl (0,075 M) and then fixed in methanol-glacial acetic acid (3:1). Flame-dried slides were stained with Giemsa, coded and scored blind. Generally 500 first-division cells per individual were

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

Chromosomal Rearrangements in Post-Chernobyl Papillary Thyroid Carcinomas: Evaluation by Spectral Karyotyping and Automated Interphase FISH

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Ludwig Hieber

2011-01-01

Full Text Available Structural genomic rearrangements are frequent findings in human cancers. Therefore, papillary thyroid carcinomas (PTCs were investigated for chromosomal aberrations and rearrangements of the RET proto-oncogene. For this purpose, primary cultures from 23 PTC have been established and metaphase preparations were analysed by spectral karyotyping (SKY. In addition, interphase cell preparations of the same cases were investigated by fluorescence in situ hybridisation (FISH for the presence of RET/PTC rearrangements using RET-specific DNA probes. SKY analysis of PTC revealed structural aberrations of chromosome 11 and several numerical aberrations with frequent loss of chromosomes 20, 21, and 22. FISH analysis for RET/PTC rearrangements showed prevalence of this rearrangement in 72% (16 out of 22 of cases. However, only subpopulations of tumour cells exhibited this rearrangement indicating genetic heterogeneity. The comparison of visual and automated scoring of FISH signals revealed concordant results in 19 out of 22 cases (87% indicating reliable scoring results using the optimised scoring parameter for RET/PTC with the automated Metafer4 system. It can be concluded from this study that genomic rearrangements are frequent in PTC and therefore important events in thyroid carcinogenesis.

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.

Caffeine-mediated release of alpha-radiation-induced G2 arrest increases the yield of chromosome aberrations

International Nuclear Information System (INIS)

Luecke-Huhle, C.; Hieber, L.; Wegner, R.D.

1983-01-01

Severe and partly irreversible G2 arrest caused by americium-241 alpha-particles in Chinese hamster V79 cells acted as a competing process to the yield of detectable aberrant mitoses at metaphase. With increasing dose of alpha-radiation an increasing fraction of cells was irreversibly arrested in G2 with the consequence of interphase death before the first post-irradiation mitosis. This irreversible G2 arrest (demonstrated by flow cytofluorometry and mitotic indices) could be overcome by adding caffeine 8 hours after irradiation, the time point of maximum G2 arrest (80-90 per cent of all cells). Within 3.5 hours the number of aberrant mitoses increased by this treatment from 54 to 96 per cent and from 65 to 99.9 per cent for doses of 1.75 and 4.38 Gy of alpha-particles, respectively. The aberration frequency per mitotic cell, scored as chromatid and isochromatid breaks, rings, interchanges and dicentrics increased by a factor of about 3 after releasing G2 arrested cells. The frequency distribution of aberrations per cell revealed that, after 4.38 Gy, 58 per cent of the formerly G2-arrested cells had more than five aberrations per cell compared to only 8 per cent without the interaction of caffeine. (author)

The impact of physical activity on the level of chromosome aberrations

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Šošić Gordana M.

2015-01-01

Full Text Available During the lifetime, people are constantly exposed to the chemicals and agents of exogenic and endogenic sources, which through reaction with a molecule of DNA can cause the damage of genomes and their instability. The formation of micronuclei is a consequence of chromosomal aberrations caused by the influence of different genetic and environmental factors. Micronuclei are cytoplasmic chromatin masses that look like small nuclei and can originate from whole or parts of chromosomes. Micronucleus test ( MN test is used to detect genotoxic effects of various chemical , physical or biological mutagens, as well as the test for determination of chromosomal instability in a variety of cell types. Micronucleus frequency is directly proportional to the degree of chromosomal aberrations. It has been shown that genome damage may occur as a result of environmental exposure to genotoxins and medical procedures, due to deficiency of micronutrients and under the influence of various lifestyles and genetic factors. Unbalanced diet, lack of physical exercise, lack of sleep and overwork contribute significantly to increased frequency of micronuclei. It was also shown that strenuous exercise causes DNA damage, which results in the formation of micronuclei. As a professional athlete conduct highly Intensive physical training, these populations are at risk for the development of genomic instability and carcinogenesis. A healthy lifestyle, the optimal intake of antioxidants and regular moderate physical activity significantly reduced the frequency of micronuclei, and contribute to the stability of the genome.

Chronic lymphocytic leukemia-associated chromosomal abnormalities and miRNA deregulation

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Kiefer Y

2012-03-01

Full Text Available Yvonne Kiefer1, Christoph Schulte2, Markus Tiemann2, Joern Bullerdiek11Center for Human Genetics, University of Bremen, Bremen, Germany; 2Hematopathology Hamburg, Hamburg, GermanyAbstract: Chronic lymphocytic leukemia is the most common leukemia in adults. By cytogenetic investigations major subgroups of the disease can be identified that reflect different routes of tumor development. Of these chromosomal deviations, trisomy 12 and deletions of parts of either the long arm of chromosome 13, the long arm of chromosome 11, or the short arm of chromosome 17 are most commonly detected. In some of these aberrations the molecular target has been identified as eg, ataxia telangiectasia mutated (ATM in case of deletions of chromosomal region 11q22~23 and the genes encoding microRNAs miR-15a/16-1 as likely targets of deletions of chromosomal band 13q14.3. Of note, these aberrations do not characterize independent subgroups but often coexist within the metaphases of one tumor. Generally, complex aberrations are associated with a worse prognosis than simple karyotypic alterations. Due to smaller sizes of the missing segment the detection of recurrent deletions is not always possible by means of classical cytogenetics but requires more advanced techniques as in particular fluorescence in situ hybridization (FISH. Nevertheless, at this time it is not recommended to replace classical cytogenetics by FISH because this would miss additional information given by complex or secondary karyotypic alterations. However, the results of cytogenetic analyses allow the stratification of prognostic and predictive groups of the disease. Of these, the group characterized by deletions involving TP53 is clinically most relevant. In the future refined methods as eg, array-based comparative genomic hybridization will supplement the existing techniques to characterize CLL. Keywords: chronic lymphocytic leukemia, chromosomal abnormality, miRNA deregulation

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)

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)

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.)

Biological dosimetry of heavy ion induced chromosome lesions in human peripheral blood lymphocytes of different healthy donors

International Nuclear Information System (INIS)

Groesser, T.; Rydberg, B.; Ritter, S.; Hessel, P.; Kraft, G.

2003-01-01

Full text: In the presented work the effect of sparsely ionizing X-rays or densely ionizing carbon ions on human peripheral blood lymphocytes (PBL) from healthy donors regarding the fluctuations in radiosensitivity within the same donor and between different donors was examined. This is not only of special interest for physicians and radiation biologists but also plays an important role in space flights because such fluctuations in the radiation response would reduce the accuracy of the biological dosimetry. In this context, biological changes in the aberration rate of metaphase cells as well as in cell proliferation and the mitotic index were measured. Since chromosome analyses are presently the most powerful biological method to quantify radiation exposure, the study focused on the measurements of chromosome aberrations in first-metaphase cells. The investigations showed that the aberration yield after 400 MeV/u carbon ion exposure (LET = 11 keV/micrometer) was higher than after X-irradiation. The aberration yield in first mitotic cells as well as the proportion of damaged cells was stable over the examined period up to 72h after exposure to X-rays or carbon ions. Furthermore, the results of the presented work revealed pronounced fluctuations in the measured parameters in the same donor as well as between different donors. If the dose effect curves of such parameters were used as calibration curves for radiation dose assessment these fluctuations will decrease their potential of use for dose estimation. This demonstrates that a general calibration curve for dose assessment might not be sufficiently precise and individual calibration curves might improve the accuracy of the biological dosimetry

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)

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.

Retrospective chromosome aberration analysis of former uranium miners

International Nuclear Information System (INIS)

Meszaros, G.; Bognar, G.; Koeteles, G. J.

2003-01-01

In this paper we present our data collected in the period of 1981-1985 on 165 persons exposed by different radon concentrations expressed in working level month (WLM) units from 100 up to 600. Following the decommissioning of the uranium mine in Hungary in 1997 cytogenetic status of 131 persons were within a follow-up-study of their health conditions initiated by the Hungarian Academy of Science. The persons have terminated their underground activities 5 to 20 years before testing. The comparison of the two datasets suggest a long-term persistence of cytogenetic alterations above the population average values in large percentages of persons investigated. The frequency of chromosome aberrations of uranium miners was found increased in function of their exposure to radon. The comparison of the miner's categories 20 years ago and in the recent years demonstrated the long-term existence of aberrations for many years after completion of underground mining activities. (authors)

Distribution of the various radiation-induced chromosomal rearrangements in relation to the dose and sampling time

International Nuclear Information System (INIS)

Dutrillaux, B.; Viegas-Pequignot, E.; Prod'homme, M.; Sportes, M.

1985-01-01

The quantitative analysis of the chromosome rearrangements detected in 2128 R-banded metaphases, obtained from γ-irradiated human lymphocytes after 48 to 96 h in culture is reported. Depending on the culture time, and possibly on the dose of radiation (from 1 to 3 Gy), the most frequent type of rearrangement was either dicentrics or reciprocal translocations. In first generation mitoses, the frequency of cells without rearrangement ranged from 0.66 to 0.18, and the mean number of rearranged chromosomes per cell from 0.79 to 3.28. The dose-response curve follows a quadratic function for dicentric aberration yields, but not for other rearrangements. (Auth.)

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

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)

Effect of mobile phone station on micronucleus frequency and chromosomal aberrations in human blood cells.

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Yildirim, M S; Yildirim, A; Zamani, A G; Okudan, N

2010-01-01

The use of mobile telephones has rapidly increased worldwide as well as the number of mobile phone base stations that lead to rise low level radiofrequency emissions which may in turn have possible harm for human health. The national radiation protection board has published the known effects of radio waves exposure on humans living close to mobile phone base stations. However, several studies have claimed that the base station has detrimental effects on different tissues. In this study, we aimed to evaluate the effects of mobile phone base stations on the micronucleus (MN) frequency and chromosomal aberrations on blood in people who were living around mobile phone base stations and healthy controls. Frequency of MN and chromosomal aberrations in study and control groups was 8.96 +/- 3.51 and 6.97 +/- 1.52 (p: 0.16); 0.36 +/- 0.31 and 0.75 +/- 0.61 (p: 0.07), respectively. Our results show that there was not a significant difference of MN frequency and chromosomal aberrations between the two study groups. The results claim that cellular phones and their base stations do not produce important carcinogenic changes.

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

Preparation and Fluorescent Analysis of Plant Metaphase Chromosomes.

Science.gov (United States)

Schwarzacher, Trude

2016-01-01

Good preparations are essential for informative analysis of both somatic and meiotic chromosomes, cytogenetics, and cell divisions. Fluorescent chromosome staining allows even small chromosomes to be visualized and counted, showing their morphology. Aneuploidies and polyploidies can be established for species, populations, or individuals while changes occurring in breeding lines during hybridization or tissue culture and transformation protocols can be assessed. The process of division can be followed during mitosis and meiosis including pairing and chiasma distribution, as well as DNA organization and structure during the evolution of chromosomes can be studied. This chapter presents protocols for pretreatment and fixation of material, including tips of how to grow plants to get good and healthy meristem with many divisions. The chromosome preparation technique is described using proteolytic enzymes, but acids can be used instead. Chromosome slide preparations are suitable for fluorochrome staining for fast screening (described in the chapter) or fluorescent in situ hybridization (see Schwarzacher and Heslop-Harrison, In situ hybridization. BIOS Scientific Publishers, Oxford, 2000).

Genomic copy number analysis of a spectrum of blue nevi identifies recurrent aberrations of entire chromosomal arms in melanoma ex blue nevus.

Science.gov (United States)

Chan, May P; Andea, Aleodor A; Harms, Paul W; Durham, Alison B; Patel, Rajiv M; Wang, Min; Robichaud, Patrick; Fisher, Gary J; Johnson, Timothy M; Fullen, Douglas R

2016-03-01

Blue nevi may display significant atypia or undergo malignant transformation. Morphologic diagnosis of this spectrum of lesions is notoriously difficult, and molecular tools are increasingly used to improve diagnostic accuracy. We studied copy number aberrations in a cohort of cellular blue nevi, atypical cellular blue nevi, and melanomas ex blue nevi using Affymetrix's OncoScan platform. Cases with sufficient DNA were analyzed for GNAQ, GNA11, and HRAS mutations. Copy number aberrations were detected in 0 of 5 (0%) cellular blue nevi, 3 of 12 (25%) atypical cellular blue nevi, and 6 of 9 (67%) melanomas ex blue nevi. None of the atypical cellular blue nevi displayed more than one aberration, whereas complex aberrations involving four or more regions were seen exclusively in melanomas ex blue nevi. Gains and losses of entire chromosomal arms were identified in four of five melanomas ex blue nevi with copy number aberrations. In particular, gains of 1q, 4p, 6p, and 8q, and losses of 1p and 4q were each found in at least two melanomas. Whole chromosome aberrations were also common, and represented the sole finding in one atypical cellular blue nevus. When seen in melanomas, however, whole chromosome aberrations were invariably accompanied by partial aberrations of other chromosomes. Three melanomas ex blue nevi harbored aberrations, which were absent or negligible in their precursor components, suggesting progression in tumor biology. Gene mutations involving GNAQ and GNA11 were each detected in two of eight melanomas ex blue nevi. In conclusion, copy number aberrations are more common and often complex in melanomas ex blue nevi compared with cellular and atypical cellular blue nevi. Identification of recurrent gains and losses of entire chromosomal arms in melanomas ex blue nevi suggests that development of new probes targeting these regions may improve detection and risk stratification of these lesions.

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.)

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 polymorphism of catechol-O-methyltransferase (COMT) and hemochromatosis (HFE) genes in the radiocontaminated regions residents with different chromosome aberration frequency].

Science.gov (United States)

Ivanova, T I; Kondrashova, T V; Krikunova, L I; Smirnova, I A; Shentereva, N I; Sychenkova, N I; Rykova, E V; Zharikova, I A; Khorokhorina, V A; Riabchenko, N I; Zamulaeva, I A

2010-01-01

The association between polymorphisms in genes COMT, HFE that takes part in oxidative stress regulation, and chromosome aberration frequency in lymphocytes was assessed in 278 female residents of radiation polluted regions of Central Russia: Bryansk (322 kBk/m2) and Tula Districts (137Cs - 171 kBk/m2). The C187G, G845A genotyping of HFE and G1947A (H/L) of COMT was done by means of polymerase chain reaction-restriction fragment length polymorphism. Studied population was divided into 3 subgroups by level of chromosome aberrations per cell (0-2, 3-4, >5). There was shown statistically significant difference in distribution of COMTand HFE genotypes between the groups. The high frequency of chromosome aberrations (> or = 5%) was associated with homozygotes of the high activity COMT G/G and HFE CC. Heterozygotes for G1947A COMT and C187G HFE reveal negative association with the high frequency of chromosome aberrations and correspond to "resistance factors".

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

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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.

ADP-ribosylation of nonhistone proteins from metaphase and interphase HeLa cells: factors responsible for differences

International Nuclear Information System (INIS)

Adolph, K.W.

1986-01-01

A striking reduction was previously detected for HeLa metaphase chromosomes, compared to interphase nuclei, in the number of modified nonhistone species. Several factors which could contribute to this cell cycle change in ADP-ribosylation have therefore been examined. In these experiments, mitotic or interphase cells were incubated with [ 32 P]NAD, chromosomes and nuclei were prepared, and the proteins were resolved by polyacrylamide gel electrophoresis. The level of incorporation of 32 P label was found to be substantially influenced by chromosome expansion, DNA nicking, disruption of chromosomes or nuclei, and the growth activity of cells. The level of ADP-ribosylation was not greatly affected by the presence of inhibitors of RNA, DNA, and protein synthesis. NAD concentration influenced the extent of labelling but not the pattern of labeled species. A similar change in the pattern from interphase to mitosis was observed for whole cells as well as for isolated chromosomes and nuclei. The procedure used to arrest cells in mitosis was not artifactually responsible for the results. The difference in metaphase and interphase ADP-ribosylation is not confined to HeLa cells, since comparable patterns were found for chromosomes and nuclei from Novikoff rat hepatoma cells

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

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

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

Chromosome aberrations in T lymphocytes carrying adult T-cell leukemia-associated antigens (ATLA) from healthy adults.

Science.gov (United States)

Fukuhara, S; Hinuma, Y; Gotoh, Y I; Uchino, H

1983-01-01

Chromosomes were studied in cultured T lymphocytes carrying adult T-cell leukemia-associated antigens (ATLA) that were obtained from five Japanese anti-ATLA seropositive healthy adults. Chromosomally abnormal cells were observed in three of the five healthy adults, and these cells were clonal in two subjects. All cells examined in one subject had rearrangements of chromosome nos. 7 and 14. Clonal cells from the second had a minute chromosome of unknown origin. A few cells in the third had nonclonal rearrangements of chromosomes. Thus, ATLA-positive T lymphocytes in some anti-ATLA seropositive healthy people have chromosome aberrations.

Intra- and Interindividual Variability in Lymphocyte Chromosomal Aberrations: Implications for Cancer Risk Assessment

Czech Academy of Sciences Publication Activity Database

Peters, S.; Portengen, L.; Bonassi, S.; Šrám, Radim; Vermeulen, R.

2011-01-01

Roč. 174, č. 4 (2011), s. 490-493 ISSN 0002-9262 Institutional research plan: CEZ:AV0Z50390512 Keywords : chromosomal aberrations frequency * cancer risk assessment Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 5.216, year: 2011

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

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.)

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

Chromosomal aberrations in blood lymphocytes of the residents of 30-km Chernobyl NPP exclusion zone

International Nuclear Information System (INIS)

Bezdrobna, Larysa; Tsyganok, Tetyana; Romanova, Olena; Tarasenko, Larysa; Tryshyn, Volodymyr; Klimkina, Ludmila

2016-01-01

A comparative cytogenetic examination of 33 self-settlers in the 30 km ChNPP Exclusion Zone and 31 residents in villages of Yahotyn district, Kyiv region was carried out in 1998-99. The levels of soil contamination of their residential areas with "1"3"7Cs, "9"0Sr and "2"3"8","2"3"9"+"2"4"0Pu were 74–477 kBq/m"2, 33–288 kBq/m"2 and 1.5-10.0 kBq/m"2, respectively for the former, and 1.9–5.8 kBq/m"2, 0.6–2.8 kBq/m"2 and 0.01-0.05 kBq/m"2, respectively for the latter. Using various data about the radiation situation in the Exclusion Zone, the effective doses on whole-body of the self-settlers were estimated to be 30–333 mSv for the whole residing period after the accident. The mean frequencies of aberrant cells and chromosomal aberrations for the Zone self-settlers were significantly higher than those for the residents in Yahotyn district, while the values of the latter group were found to be above the spontaneous levels reported in literatures. The individual variability in the distribution of the same indices was significantly larger for the self-settlers than for the Yahotyn residents. The compared groups also differ in the distribution of aberrations in cells. A repeated examination of 20 Zone self-settlers was conducted in 2001. A significant decrease in chromosome type aberration frequency was found at the expense of fragments frequency decrease. However, the total frequency of chromosomal aberrations didn't differ in 1998-99 and in 2001. (author)

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)

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)

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

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

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

Dose-response calibration curves of {sup 137}Cs gamma rays for dicentric chromosome aberrations in human lymphocytes

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Jo, Wol Soon; Oh, Su Jung; Jeong, Soo Kyun; Yang, Kwang Mo [Dept. of Research center, Dong Nam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Jeong, Min Ho [Dept. of Microbiology, Dong A University College of Medicine, Busan (Korea, Republic of)

2012-11-15

Recently, the increased threat of radiologically industrial accident such as radiation nondestructive inspection or destruction of nuclear accident by natural disaster such as Fukushima accident requires a greater capacity for cytogenetic biodosimetry, which is critical for clinical triage of potentially thousands of radiation-exposed individuals. Dicentric chromosome aberration analysis is the conventional means of assessing radiation exposure. Dose–response calibration curves for {sup 13}'7Cs gamma rays have been established for unstable chromosome aberrations in human peripheral blood lymphocytes in many laboratories of international biodosimetry network. In this study, therefore, we established dose– response calibration curves of our laboratory for {sup 137}Cs gamma raysaccording to the IAEA protocols for conducting the dicentric chromosome assay We established in vitro dose–response calibration curves for dicentric chromosome aberrations in human lymphocytes for{sup 13}'7Cs gamma rays in the 0 to 5 Gy range, using the maximum likelihood linear-quadratic model, Y = c+αD+βD2. The estimated coefficients of the fitted curves were within the 95% confidence intervals (CIs) and the curve fitting of dose–effect relationship data indicated a good fit to the linear-quadratic model. Hence, meaningful dose estimation from unknown sample can be determined accurately by using our laboratory’s calibration curve according to standard protocol.

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

Chromosome aberrations and oncogene alterations in atomic bomb related leukemias - different mechanisms from de novo leukemias

International Nuclear Information System (INIS)

Tanaka, K.; Tanaka, H.; Kamada, N.

2003-01-01

It is well known that leukemia occurred more frequently among atomic bomb survivors. In 132 atomic bomb related ( AB- related) leukemia patients during 1978-1999, 33 acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) patients had their exposure doses of more than 1Gy (DS86). Chromosome aberrations of the 33 patients were compared with those from 588 de novo AML/MDS patients who had been bone before August 1945 as control. No FAB M3 patient was observed in the exposed group. Most AB-related AML preceded a long term of MDS stage. Twenty seven of the 33 patients showed complex types of chromosome aberrations with more than three chromosomes involving chromosomes 5,7 and 11. The number of chromosomes abnormality per cell in the AB-related leukemia was 3.78 while 0.92 in de novo leukemia. Only one of the 33 patients had normal karyotype, while 44.1% in de novo leukemia patients. Translocations of chromosome 11 at 11q13 to 11q23 and deletion/ loss of chromosome 20 were frequently observed in AB-related leukemia. No leukemia-type specific translocations such as t(8;21),t(15;17) and 11q23 were found in the 33 AB-related leukemia patients. Furthermore, molecular analyses using FISH and PCR-SSCP revealed the presence of breakpoint located outside of MLL gene in the patients with translocations at 11q22-23 and DNA base derangements of RUNT domain of AML1(CBF β 2)gene with AML/MDS patients without t(8;21) and with a high dose of exposure. These results suggest that AB-related leukemia derives from an exposed pluripotent hematopoietic stem cell which has been preserved for a long time in the bone marrow, expressing high genetic instability such as microsatellite instability. On the other hand, de novo leukemia develops from a committed hematopoietic stem cell and shows simple and leukemia-type specific chromosome aberrations. These findings are important for understanding mechanisms for radiation-induced leukemia

Radioactivity and chromosome aberrations of residents of Misasa Spa

International Nuclear Information System (INIS)

Morinaga, Hiroshi; Mifune, Masaaki; Furuno, Katsushi

1985-01-01

Misasa Spa is one of the most highly radioactive hot springs in Japan, the waters of which contain mainly 222 Rn (437 ± 132 Bq/liter). Radon contents of indoor air of private houses and health resort hotels (built of wood) at Misasa Spa range from 18.5 to 55.5 mBq/liter and 22.2 to 129.5 mBq/liter, respectively. Radon contents in the air of facilities using spring waters at Misasa Branch Hospital of Okayama University were measured to be; bathroom 807 ± 78 mBq/liter; Hubbardtank bathroom 5306 ± 2568 mBq/liter; the drinking hall 1491 ± 178 mBq/liter. The environmental and dose rate inside private house's has been measured to be 14.0 ± 1.8 μR/h. Chromosome aberrations (dicentrics) in the peripheral blood lymphocytes of residents of Misasa Spa were investigated in 14 persons; the mean value of aberration frequencies were 0.21 %. (Kubozono, M.)

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

Chromosome studies on bone marrow cells of chinese hamsters fed a radiosterilized diet

International Nuclear Information System (INIS)

Renner, H.W.

1977-01-01

Metaphase preparations of chromosomes from bone marrow cells of Chinese hamsters were examined for mutagenic effects following the feeding of a radiosterilized diet. No increase in the incidence of structural chromosomal aberrations was observed. As far as numerical aberrations were concerned, the proportion of cells with polyploidy increased to between 4 to 5 times the control level, irrespective of the moisture content of the diet. This polyploidy effect occurred very early, being detectable within 24 h, if the diet fed had been irradiated with an absorbed dose of 4.5x10 6 rad. The incidence of polyploidy remained below 0.5%, however, nor did it rise with higher radiation doses. When the feeding of the irradiated diet was stopped, the proportion of polyploid cells returned to the control level within a maximum of 6 weeks. If the diet was stored (initially) for 6 weeks following irradiation before being fed to the animals no increase in the number of polyploid cells was noted. These results are not interpreted as a mutagenic effect of the irradiated diet. (author)

GeneBreak: detection of recurrent DNA copy number aberration-associated chromosomal breakpoints within genes [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Evert van den Broek

2017-07-01

Full Text Available Development of cancer is driven by somatic alterations, including numerical and structural chromosomal aberrations. Currently, several computational methods are available and are widely applied to detect numerical copy number aberrations (CNAs of chromosomal segments in tumor genomes. However, there is lack of computational methods that systematically detect structural chromosomal aberrations by virtue of the genomic location of CNA-associated chromosomal breaks and identify genes that appear non-randomly affected by chromosomal breakpoints across (large series of tumor samples. ‘GeneBreak’ is developed to systematically identify genes recurrently affected by the genomic location of chromosomal CNA-associated breaks by a genome-wide approach, which can be applied to DNA copy number data obtained by array-Comparative Genomic Hybridization (CGH or by (low-pass whole genome sequencing (WGS. First, ‘GeneBreak’ collects the genomic locations of chromosomal CNA-associated breaks that were previously pinpointed by the segmentation algorithm that was applied to obtain CNA profiles. Next, a tailored annotation approach for breakpoint-to-gene mapping is implemented. Finally, dedicated cohort-based statistics is incorporated with correction for covariates that influence the probability to be a breakpoint gene. In addition, multiple testing correction is integrated to reveal recurrent breakpoint events. This easy-to-use algorithm, ‘GeneBreak’, is implemented in R (www.cran.r-project.org and is available from Bioconductor (www.bioconductor.org/packages/release/bioc/html/GeneBreak.html.

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.

Metaphase FISH on a Chip: Miniaturized Microfluidic Device for Fluorescence in situ Hybridization

Directory of Open Access Journals (Sweden)

Niels Tommerup

2010-11-01

Full Text Available Fluorescence in situ Hybridization (FISH is a major cytogenetic technique for clinical genetic diagnosis of both inherited and acquired chromosomal abnormalities. Although FISH techniques have evolved and are often used together with other cytogenetic methods like CGH, PRINS and PNA-FISH, the process continues to be a manual, labour intensive, expensive and time consuming technique, often taking over 3–5 days, even in dedicated labs. We have developed a novel microFISH device to perform metaphase FISH on a chip which overcomes many shortcomings of the current laboratory protocols. This work also introduces a novel splashing device for preparing metaphase spreads on a microscope glass slide, followed by a rapid adhesive tape-based bonding protocol leading to rapid fabrication of the microFISH device. The microFISH device allows for an optimized metaphase FISH protocol on a chip with over a 20-fold reduction in the reagent volume. This is the first demonstration of metaphase FISH on a microfluidic device and offers a possibility of automation and significant cost reduction of many routine diagnostic tests of genetic anomalies.

Interphase Chromosome Profiling: A Method for Conventional Banded Chromosome Analysis Using Interphase Nuclei.

Science.gov (United States)

Babu, Ramesh; Van Dyke, Daniel L; Dev, Vaithilingam G; Koduru, Prasad; Rao, Nagesh; Mitter, Navnit S; Liu, Mingya; Fuentes, Ernesto; Fuentes, Sarah; Papa, Stephen

2018-02-01

- Chromosome analysis on bone marrow or peripheral blood samples fails in a small proportion of attempts. A method that is more reliable, with similar or better resolution, would be a welcome addition to the armamentarium of the cytogenetics laboratory. - To develop a method similar to banded metaphase chromosome analysis that relies only on interphase nuclei. - To label multiple targets in an equidistant fashion along the entire length of each chromosome, including landmark subtelomere and centromere regions. Each label so generated by using cloned bacterial artificial chromosome probes is molecularly distinct with unique spectral characteristics, so the number and position of the labels can be tracked to identify chromosome abnormalities. - Interphase chromosome profiling (ICP) demonstrated results similar to conventional chromosome analysis and fluorescence in situ hybridization in 55 previously studied cases and obtained useful ICP chromosome analysis results on another 29 cases in which conventional methods failed. - ICP is a new and powerful method to karyotype peripheral blood and bone marrow aspirate preparations without reliance on metaphase chromosome preparations. It will be of particular value for cases with a failed conventional analysis or when a fast turnaround time is required.

WE-D-BRE-05: Prediction of Late Radiation-Induced Proctitis in Prostate Cancer Patients Using Chromosome Aberration and Cell Proliferation Rate

Energy Technology Data Exchange (ETDEWEB)

Oh, J; Deasy, J [Memorial Sloan Kettering Cancer Center, New York, NY (United States)

2014-06-15

Purpose: Chromosome damage and cell proliferation rate have been investigated as potential biomarkers for the early prediction of late radiationinduced toxicity. Incorporating these endpoints, we explored the predictive power for late radiation proctitis using a machine learning method. Methods: Recently, Beaton et al. showed that chromosome aberration and cell proliferation rate could be used as biomarkers to predict late radiation proctitis (Beaton et al. (2013) Int J Rad Onc Biol Phys, 85:1346–1352). For the identification of radiosensitive biomarkers, blood samples were collected from 10 patients with grade 3 late proctitis along with 20 control patients with grade 0 proctitis. After irradiation at 6 Gy, statistically significant difference was observed between the two groups, using the number of dicentrics and excess fragments, and the number of cells in metaphase 2 (M2). However, Beaton et al. did not show the usefulness of combining these endpoints. We reanalyzed the dataset to investigate whether incorporating these endpoints can increase the predictive power of radiation proctitis, using a support vector machine (SVM). Results: Using the SVM method with the number of fragments and M2 endpoints, perfect classification was achieved. In addition, to avoid biased estimate of the classification method, leave-one-out cross-validation (LOO-CV) was performed. The best performance was achieved when all three endpoints were used with 87% accuracy, 90% sensitivity, 85% specificity, and 0.85 AUC (the area under the receiver operating characteristic (ROC) curve). The most significant endpoint was the number of fragments that obtained 83% accuracy, 70% sensitivity, 90% specificity, and 0.82 AUC. Conclusion: We demonstrated that chromosome damage and cell proliferation rate could be significant biomarkers to predict late radiation proctitis. When these endpoints were used together in conjunction with a machine learning method, the better performance was obtained

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)

DEMONSTRATION OF THE GENUINE ISO-12P CHARACTER OF THE STANDARD MARKER CHROMOSOME OF TESTICULAR GERM-CELL TUMORS AND IDENTIFICATION OF FURTHER CHROMOSOME-12 ABERRATIONS BY COMPETITIVE INSITU HYBRIDIZATION

NARCIS (Netherlands)

SUIJKERBUIJK, RF; VANDEVEEN, AY; VANECHTEN, J; BUYS, CHCM; DEJONG, B; OOSTERHUIS, JW; WARBURTON, DA; CASSIMAN, JJ; SCHONK, D; VANKESSEL, AG

The recently developed competitive in situ hybridization (CISH) strategy was applied to the analysis of chromosome 12 aberrations in testicular germ cell tumors (TGCTs). DNAs from two rodent-human somatic cell hybrids, containing either a normal chromosome 12 or the p arm of chromosome 12 as their

Stabilization of chromosomes by DNA intercalators for flow karyotyping and identification by banding of isolated chromosomes

NARCIS (Netherlands)

Aten, J. A.; Buys, C. H.; van der Veen, A. Y.; Mesa, J. R.; Yu, L. C.; Gray, J. W.; Osinga, J.; Stap, J.

1987-01-01

A number of structurally unrelated DNA intercalators have been studied as stabilizers of mitotic chromosomes during isolation from rodent and human metaphase cells. Seven out of the nine intercalators tested were found to be useful as chromosome stabilizing agents. Chromosome suspensions prepared in

mFISH analysis of chromosome aberrations in workers occupationally exposed to mixed radiation

Energy Technology Data Exchange (ETDEWEB)

Sotnik, Natalia V.; Osovets, Sergey V.; Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region (Russian Federation); Scherthan, Harry [Bundeswehr Institute of Radiobiology Affiliated to the University of Ulm, Munich (Germany)

2014-05-15

We performed a study on the presence of chromosome aberrations in a cohort of plutonium workers of the Mayak production association (PA) with a mean age of 73.3 ± 7.2 years to see whether by multi-color fluorescence in situ hybridization (mFISH) translocation analysis can discriminate individuals who underwent occupational exposure with internal and/or external exposure to ionizing radiation 40 years ago. All Mayak PA workers were occupationally exposed to chronic internal alpha-radiation due to incorporated plutonium-239 and/or to external gamma-rays. First, we obtained the translocation yield in control individuals by mFISH to chromosome spreads of age-matched individuals and obtained background values that are similar to previously published values of an international study (Sigurdson et al. in Mutat Res 652:112-121, 2008). Workers who had absorbed a total dose of >0.5 Gy external gamma-rays to the red bone marrow (RBM) displayed a significantly higher frequency of stable chromosome aberrations relative to a group of workers exposed to <0.5 Gy gamma-rays total absorbed RBM dose. Thus, the translocation frequency may be considered to be a biological marker of external radiation exposure even years after the exposure. In a group of workers who were internally exposed and had incorporated plutonium-239 at a body burden >1.48 kBq, mFISH revealed a considerable number of cells with complex chromosomal rearrangements. Linear associations were observed for translocation yield with the absorbed RBM dose from external gamma-rays as well as for complex chromosomal rearrangements with the plutonium-239 body burden. (orig.)

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

DNA Catenation Maintains Structure of Human Metaphase Chromosomes

DEFF Research Database (Denmark)

L. V. Bauer, David; Marie, Rodolphe; Rasmussen, Kristian Hagsted

2012-01-01

Mitotic chromosome structure is pivotal to cell division but difficult to observe in fine detail using conventional methods. DNA catenation has been implicated in both sister chromatid cohesion and chromosome condensation, but has never been observed directly. We have used a lab-on-a-chip microfl...

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

Energy Technology Data Exchange (ETDEWEB)

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.

Chromosomal Aberrations Associated with Clonal Evolution and Leukemic Transformation in Fanconi Anemia: Clinical and Biological Implications

Directory of Open Access Journals (Sweden)

Stefan Meyer

2012-01-01

Full Text Available Fanconi anaemia (FA is an inherited disease with congenital and developmental abnormalities, bone marrow failure, and extreme risk of leukemic transformation. Bone marrow surveillance is an important part of the clinical management of FA and often reveals cytogenetic aberrations. Here, we review bone marrow findings in FA and discuss the clinical and biological implications of chromosomal aberrations associated with leukemic transformation.

Analysis of chromosomal aberration in seven medical staffs suspected with exposure to ionizing radiation

International Nuclear Information System (INIS)

Han Lin; Zhao Fengling; Wang Xi'ai; Wang Ping; Jiang Feng; Lu Yumin

2012-01-01

Objective: To investigate the chromosomal aberrations in seven medical staffs suspected with exposure to ionizing radiation and to speculate its possible causation. Methods: The hospital staffs, including 6 females and 1 male,worked in a clinical laboratory where a CT room was located downstairs. The thickness of precast slab between these two rooms was 6 cm. Peripheral blood lymphocytes of seven staffs were examined for conventional chromosomal aberrations. Results: The frequencies of dicentrics in the peripheral lymphocytes of 4 females were from 0.40% to 1.60% that was significantly higher than the spontaneous frequency of dicentrics (0.03%, χ 2 =36.79, P<0.05). The translocation was observed in the lymphocytes from all subjects with frequencies from 0.33% to 1.20%, obviously higher than its spontaneous frequency of 0.01% (χ 2 =42.90, P<0.05). Conclusion: These staffs suffer from ionizing radiation. (authors)

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)

Induction of chromosome aberrations in two lines of cultured cells using different types of radiation

International Nuclear Information System (INIS)

Zoetelief, J.; Dingjan-Hirschi, E.S.; Hasper, J.; Janse, H.C.; Barendsen, G.W.

The induction of chromosome aberrations has been investigated in two lines of cultured cells for different types of radiation. The obtained results are compared with information on induction of cell reproductive death and malignant transformation. (Auth.)

Analysis of chromosomal aberrations, micronuclei and hematological disorders among workers of wireless communication instruments and cell phone (Mobile) users

International Nuclear Information System (INIS)

Eldawy, H.A.; Khattab, F.I.; Hassan, N.H.A.; Amin, Y.M.; Mahmoud, M.M.A.

2003-01-01

This study was carried out to investigate the hazardous effect of electromagnetic radiation (EMR) such as chromosomal aberration, disturbed micronucleus formation and hematological disorders that may detected among workers of wireless communication instruments and mobile phone users. Seven individuals ( 3 males and 4 females) of a central workers in the microwave unit of the wireless station and 7 users of Mobil phone (4 males and 3 females ) were volunteered to give blood samples. Chromosomes and micronucleus were prepared for cytogenetic analysis as well as blood film for differential count. The results obtained in the microwave group indicated that, the total summation of all types of aberrations (chromosomes and chromatid aberrations) had a frequency of 6. 14% for the exposed group, whereas, the frequency in the control group amounted to 1.57%. In Mobil phone users, the total summation of all types of aberrations(chromosome and chromatid aberrations) had a frequency of 4.43% for the exposed group and 1.71% for the control group. The incidence of the total number of micronuclei in the exposed microwave group was increased 4.3 folds as compared with those of the control group The incidence of the total number of micronuclei in the exposed mobile phone group was increased 2 fold as compared with those in the control group. On the other hand, normal ranges of total white blood cells counts were determined for mobile phone users but abnormalities in the differential counts of the different types of the white blood cells such as neutropenia, eosinophilia and lymphocytosis were observed in the individuals number 1,2,3,7 in microwave group

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

Premature chromosome condensation and cell separation studies in biopsies from head and neck tumors for radiosensitivity prediction

International Nuclear Information System (INIS)

Begg, Adrian C.; Sprong, Debbie; Balm, Alfons; Coco Martin, Jose M.

2002-01-01

Background and purpose: Intrinsic radiosensitivity of tumor cells from biopsies, assayed by colony formation after in vitro irradiation, has shown significant correlations with outcome after radiotherapy. Alternatives to the colony assay have been sought due to its long and cumbersome nature. We have previously shown good correlations between colony formation and radiation-induced chromosome aberrations in human tumor cell lines. In addition, we and others have shown on cell lines that premature chromosome condensation (PCC) induced with phosphatase inhibitors can be used to aid rapid assessment of aberrations in interphase cells, reducing the selection problem with metaphases. The purpose of this study was to translate the in vitro results to human cancer, with the aim of developing a rapid assay for intrinsic radiosensitivity. Methods and results: The problem of admixtures of normal and malignant cells in biopsies was addressed using magnetic bead separation (MACS) employing antibodies to human fibroblasts. This proved to be a reliable and efficient method, enriching mean tumor cell fractions from 20 to almost 80%. PCC could be induced in human normal and tumor cell lines, and in sorted or unsorted suspensions from biopsies, with the phosphatase inhibitor calyculin A. Maximum PCCs were achieved after 1-week culture of biopsy-derived cells. Mean fractions of aneuploid tumor cell PCCs were, however, less than 1%. PCCs were predominantly from S and G2 phase, of which only G2 were scorable for aberrations. Almost no G1 PCCs were found. More scorable PCCs were found after 1 h of calyculin A than metaphases after 5 h of colcemid, but these were calculated to be too few to yield reliable estimates of chromosome damage after radiation. Conlcusions: Tumor cells can be satisfactorily separated from fibroblasts in fresh suspensions from cancer biopsies, but poor growth of tumor cells in short term culture and low yields of PCCs combine to prevent the routine use of such

Doses in radiation accidents investigated by chromosome aberration analysis

International Nuclear Information System (INIS)

Lloyd, D.C.; Purrott, R.J.; Prosser, J.S.; Dolphin, G.W.; Tipper, P.A.; Reeder, E.J.; White, C.M.; Cooper, S.J.; Stephenson, B.D.

1977-01-01

Results from cytogenetic investigations into 66 cases of suspected over-exposure to radiation during 1976 are reviewed. This report is the sixth in an annual series which together contain data on 272 studies. Previous results were published in NRPB-R5, R10, R23, R35 and R41. Results from all investigations have been pooled for general analysis. Brief accounts are given in an appendix of the circumstances behind the past year's investigations and, where possible, physical estimates of dose have been included for comparison. A short review is given of the laboratory's recently published dose response data for several energies of neutron radiation. A description is also given of the group's collaboration in an international experiment in which comparisons were made between a variety of dosemeters exposed to a controlled criticality pulse. In a second appendix two experiments are described in which inter- and intra-donor effects on chromosome aberration yields were examined. It was found that differences in dicentric yields were small whereas acentric aberrations were more variable. (author)

Sex reversal in the mouse (Mus musculus) is caused by a recurrent nonreciprocal crossover involving the x and an aberrant y chromosome.

Science.gov (United States)

Singh, L; Jones, K W

1982-02-01

Satellite DNA (Bkm) from the W sex-determining chromosome of snakes, which is related to sequences on the mouse Y chromosome, has been used to analyze the DNA and chromosomes of sex-reversed (Sxr) XXSxr male mice. Such mice exhibit a male-specific Southern blot Bkm hybridization pattern, consistent with the presence of Y-chromosome DNA. In situ hybridization of Bkm to chromosomes of XXSxr mice shows an aberrant concentration of related sequences on the distal terminus of a large mouse chromosome. The XYSxr carrier male, however, shows a pair of small chromosomes, which are presumed to be aberrant Y derivatives. Meiosis in the XYSxr mouse involves transfer of chromatin rich in Bkm-related DNA from the Y-Y1 complex to the X distal terminus. We suggest that this event is responsible for the transmission of the Sxr trait.

Comparative study of dose-response curve for chromosome aberrations induced in human lymphocytes by {sup 60}Co and X-Rays

Energy Technology Data Exchange (ETDEWEB)

Mendes, Mariana E.; Mendonça, Julyanne C.G.; Andrade, Aida M.G.; Silva, Laís M.; Hwang, Suy; Melo, Ana M.M.A.; Santos, Neide; Lima, Fabiana F., E-mail: mendes_sb@hotmail.com [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

2017-11-01

Biodosimetry represents a biological marker to the estimation of health risks after accidental overexposure to ionizing radiation. Chromosomal dicentric in peripheral blood lymphocytes have been the most reliable biomarker of exposure to IR during the last several decades. This technique could be used to support physical dosimetry or when it is impossible to achieve it. A reliable measurement of the absorbed dose is critical for medical decision, including the assessment of long-term health consequences. The aim of this research is to compare dose-response curves for dicentric aberration induced in human lymphocytes by {sup 60}Co and X-Rays. For both quality of radiation, the samples were exposed to at least eight different absorbed doses. The X-rays with dose rate of 0,275 Gy/min at Laboratory of Metrology (CRCN/NE - PE - Brazil) and the second one was exposed to cobalt source with dose rate of 0.055 Gy/min ({sup 60}Co Gammacell 220) located at Department of Nuclear Energy (UFPE-DEN-BRASIL). Mitotic metaphase cells were obtained by lymphocyte culture for chromosomal analysis and slides were stained with Giemsa 5%. The frequencies of dicentrics were counted in more than 18.000 metaphases for this comparison. After that, all frequencies and distributions of dicentrics were tested to analyze their conformity with Poisson distribution and then each quality of radiation were used for build the calibration curves using Dose Estimate program. These results showed that both curves followed the Poisson distribution and coefficients of each one are: YX-rays = 0,0013 (± 0,0006) + 0,0271 (± 0,0086)⁎D + 0,0556(±0,0050))⁎D{sup 2} and Y{sub Co-60} = 0,0014 (± 0,0010) + 0,0081 (± 0,0073))⁎D + 0,0451 (± 0,0046))⁎D{sup 2} (Y = frequency of dicentrics and D = absorbed dose). It was expected that there was no significant difference between this two types of radiation because both were low LET. We believed that dose rate have been a principal factor to produce this

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

Six years of cytogenetic follow-up of unstable chromosome aberrations in Goiania patients

International Nuclear Information System (INIS)

Ramalho, A.T.; Curado, M.P.; Natarajan, A.T.; Cohen, J.A.

2000-01-01

Following the radiological accident which occurred in the city of Goiania (Brazil), in September of 1987, a cytogenetic follow-up of 16 exposed patients was started, aiming to observe the mean life time of lymphocytes containing dicentric and ring aberrations. The results suggest that for the highly exposed individuals (doses above 1 Gy) the disappearance rate of unstable aberrations follows a two-term exponential function. Up to 470 days after exposure, there is a rapid fall in the aberration frequency. After 470 days, the disappearance rate is very slow. These results may reflect different subpopulations of human lymphocytes, with different life spans. The estimated average half-time of elimination of dicentrics and rings among the highly exposed group (doses above 1 Gy) was 140 days for the initial period after the exposure (up to 470 days). This value is significantly shorter than the usually accepted value of 3 years reported in the literature. For the individuals who had received less than 1 Gy the disappearance of aberrations seems to have occurred in a slower way. Mean disappearance functions of unstable chromosome aberrations were inferred, to be applied in accident situations in which there is a blood sampling delay. (author)

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.)

A note on chromosomes of Pontellopsis herdmani and Pontella princeps (Copepoda) from the Laccadive sea

Digital Repository Service at National Institute of Oceanography (India)

Goswami, U.; Goswami, S.C.

Pontellopsis herdmani and Pontella princeps (Pontellidae, Calanoida, Copepoda) showed a diploid number of 20 and a haploid number of 10 chromosomes during the spermatogonial metaphase and metaphase II stages. The chromosomes were in the size range...

Analysis of chromosome rearrangements on the basis of synaptonemal complexes in the offspring of mice exposed to γ-rays

International Nuclear Information System (INIS)

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

1986-01-01

Electron-microscopic analysis of synaptonemic complexes (SC), spread on the hypophase surface, was conducted to investigate chromosome rearrangements in sterile and semisterile F 1 malemause offsprings, exposed to 5 Gy γ-rays Paralelly Chromosome rearrangement account in diakinesis-metaphase 1 was conducted using light microscope, in the same animals. During SC analysis in pachytene chromosome rearrangements were found in 63% of spermatocytes. Under chromosome analysis in diakinesis-metaphase 1 in the same animals chromosome rearrangements were found only in 32% of cells. SC analysis allows one to reveal chromosome rearrangements, which can not be revealed in diakinesis-metaphase 1

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

Energy Technology Data Exchange (ETDEWEB)

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).