Biomedical subjects

I D Adler

Publications and source records attributed to I D Adler.

At least 73 records · Page 4Linked to original sources

PubMed1993

Somatic cell hybrid mapping on mouse chromosome 11 (MMU11): assignment of markers relative to two breakpoints in band D.

Mouse x rat somatic cell hybrids were generated by fusing mouse cell lines that are heterozygous for reciprocal translocations involving the T42H and T9Ad breakpoints on mouse chromosome 11 (MMU11) to a thymidine kinase-negative (Tk-) rat cell line, RT2Tk-. Selection in HAT medium with geneticin disulfate (G418) resulted in some hybrid clones retaining only one derivative translocation chromosome with that part of MMU11 carrying the Tk-1 locus. Southern blot and PCR analyses of these hybrids were used to map the two breakpoints and 30 markers relative to them. The T42H breakpoint has been localized between Mpo and the Cola-1/Hox-2 cluster of loci and is proximal to the T9Ad breakpoint. The T9Ad breakpoint is proximal to the distal loci Tk-1, Gaa, D11Jkn1, and P4hb. The positions of 14 loci (Hox-2, Cola-1, Rara, Phb, Erba, Rnula-1, D11Pas1, Gfap, D11Mit13, D11Mit11, D11Mit12, Myla, Empb3 and Gh) have been further refined by their localization between the two breakpoints in band D. This study therefore improves the correlation of the genetic and physical maps of MMU11 and extends the known homology between MMU11 and human chromosome 17 (HSA17) by the assignment of three additional HSA17 markers, the profilin gene, Pfn, an anonymous marker, D17s28h, and the Crk oncogene, to above the T42H breakpoint; and the prohibitin gene, Phb, to between the T42H and T9Ad breakpoints in band D on MMU11.

Animals↗

PubMed1993

Synopsis of the in vivo results obtained with the 10 known or suspected aneugens tested in the CEC collaborative study.

The synopsis of the in vivo test results in the first collaborative CEC Aneuploidy Project with 10 selected chemicals, colchicine (COL), econazole (EZ), chloral hydrate (CH), hydroquinone (HQ), diazepam (DZ), thiabendazole (TB), cadmium chloride (CD), thimerosal (TM), pyrimethamine (PY) and vinblastine (VBL), allowed several conclusions. (1) The spindle poisons, COL and VBL, were positive in all bone marrow and germ cell tests; (2) the clastogen HQ also induced aneuploidy in somatic and germinal cells; (3) the other seven compounds gave contradictory results either between laboratories or between test systems which require further experimental clarification; (4) CREST labeling or in situ hybridization for centromere identification showed about 70% fluorescent signals in micronuclei induced by COL or VBL but only about 15% in HQ induced micronuclei; (5) the tests for induction of a delay in cell division progression can be recommended as a prescreen for possible aneugens; (6) all test methods applied in these experiments require standardization with respect to sample size, sampling times and statistical treatment of the data. A second CEC Aneuploidy Programme has started recently to answer some of the questions raised by the first study regarding tissue and sex specificities.

Aneuploidy↗

PubMed1993

Perturbation of cell division by acrylamide in vitro and in vivo.

Exposure of V79 Chinese hamster cells to acrylamide (AA) caused a concentration-dependent increase in the incidence of spindle disturbances. A c-mitotic effect with the appearance of C-metaphases, a mitotic block and the concomitant disappearance of ana-telophase figures, was observed after 6 h of treatment with concentrations ranging from 0.01 to 1.0 mg/ml of AA. Intraperitoneal injection of male mice with the highest tolerated dose of 120 mg/kg of AA showed no mitotic arrest in bone marrow cells. However, 1 h and 3 h after treatment the frequencies of cells with highly condensed and separated chromatids was reduced indicating an effect on mitotic progression. In spermatocytes of mice AA caused a meiotic delay from 2 h to 22 h after treatment determined by a reduced ratio of second/first meiotic divisions. The meiotic delay was predominantly due to a prolongation of interkinesis. The present results show that AA causes disturbances of cell division in vitro and in vivo. They suggest that AA might induce aneuploidy in mammalian cells in vitro by interfering with proper functioning of the spindle similar to the effect of colchicine. In vivo, particularly in spermatocytes, the progression of cell division was altered by AA. It cannot be explained simply by an effect on spindle function, however, this alteration may also cause errors in chromosome segregation.

Acrylamide↗

PubMed1993

Parental imprinting on the mouse X chromosome: effects on the early development of X0, XXY and XXX embryos.

To examine the effects of X-chromosome imprinting during early mouse embryogenesis, we attempted to produce XM0, XP0, XMXMY, XMXPY and XMXMXP (where XM and XP stand for the maternally and the paternally derived X chromosome, respectively) making use of mouse strains bearing the translocation Rb(X.2)2Ad and the inversion In(X)1H. Unlike XMXPY embryos, XMXMY and XMXMXP conceptuses suffered from severe growth retardation or abnormal development characterized by deficient extra-embryonic structures at 6.5-7.5 days post coitum (dpc). A cytogenetic study suggested that two XM chromosomes remaining active in certain nonepiblast cells were responsible for the serious developmental abnormality found in these embryos disomic for XM. Although matings involving females heterozygous for Rb(X.2)Ad hinted at the paucity of XP0 embryos relative to those having the complementary karyotype of XMXMXP, further study of embryos from matings between females heterozygous for In(X)1H and Rb2Ad males did not substantiate this observation. Thus, the extensive peri-implantation loss of XP0 embryos shown by Hunt (1991) may be confined to X0 mothers. Taken together, this study failed to reveal a parentally imprinted X-linked gene essential for early mouse embryogenesis other than the one most probably corresponding to the X-chromosome inactivation centre.

Animals↗

PubMed1993

Flow cytometric detection of micronuclei induced by chemicals in poly- and normochromatic erythrocytes of mouse peripheral blood.

In order to standardize automated scoring for the in vivo micronucleus (MN) test a flow cytometric method which recognized micronucleated polychromatic erythrocytes (MPCE) and micronucleated normochromatic erythrocytes (MNCE) in mouse peripheral blood developed by Grawé et al. (1992) has been modified and applied. Blood samples were purified with 35% percoll solution and stained with the RNA-specific dye thiazole orange (TO) and with the DNA-specific dye Hoechst 33342 (HO) for dual laser flow cytometry. The TO fluorescent signals permitted the discrimination between polychromatic and normochromatic erythrocytes (PCE and NCE). Cytotoxic effects could be assessed by the reduction of PCE counts. The blue fluorescent signals of HO permitted the scoring of MN. The MPCE and MNCE were flow sorted for microscopic analysis and showed that 95% of the sorted cells actually contained MN. Three model chemicals, the clastogen mitomycin C, the aneugen colchicine and the industrial chemical acrylamide were tested at 24 h intervals after single intraperitoneal injection up to 72 h after treatment of male (102/ElxC3H/El)F1 mice. All three chemicals showed a dose-related maximum of the MPCE frequencies at 48 h while the MNCE frequencies stayed within the control range up to 72 h. The data obtained with the flow cytometric method were in good agreement with published results. The flow cytometric technique presented here is a fast, accurate and automated method for quantifying MPCE and MNCE in peripheral blood as an indicator of cytogenetic damage induced in the bone marrow and scored in peripheral blood samples. With minor modifications the technique will also be applicable to bone marrow samples.

Acrylamide↗

PubMed1993

A mouse stock with 38 chromosomes derived from the reciprocal translocation T(7;15)33Ad.

A reciprocal translocation, T(7;15)33Ad, with presumed breakpoints in bands 7A1 and 15F3 was induced in late spermatids by injecting male (102/E1 x C3H/E1)F1 mice five times with acrylamide (50 mg/kg body weight). Outcrosses of the original semisterile T(7;15) female generated three males monosomic for the short marker 7(15) [Ms(7(15))] among a total of 15 males. The Ms(7(15)) males sired small litters and had reduced testes weights. From inter se matings of Ms(7(15)) animals, nullisomic progeny for chromosome 7(15) were obtained and mated to produce a breeding stock of mice with 38 chromosomes. For comparison, mice carrying the reciprocal translocation T(4;8), with similarly located breakpoints, were also analyzed. Fluorescent in situ hybridization (FISH) with major and minor satellite DNA probes and a telomeric DNA probe was utilized. The observed FISH signals suggest that in chromosomes 7 and 8 the breaks occurred within the pericentric heterochromatic block immediately below the centromere and in chromosomes 15 and 4 at a point near the distal telomeres. The long markers 15(7)and 4(8) are tandem fusion chromosomes. The short markers 7(15) and 8(4) also showed all appropriate FISH signals for intact chromosomes. The loss of the small chromosome 7(15) was compatible with survival, suggesting that no essential genes are located on the small reciprocal translocation product. The development of this tandem fusion stock is described as a laboratory example of one possible step in karyotypic evolution.

Animals↗

PubMed1993

Development of screening tests for aneuploidy induction by environmental pollutants.

When legally required mutagenicity testing of chemicals is undertaken, the important genetic end point of aneuploidy is not included because validated test methods are lacking. Therefore, the Commission of the European Communities (CEC) has funded a research program to develop and validate tests for aneuploidy induction. Ten chemicals, selected on the basis of their ability to interact with cell organelles relevant for aneuploidy induction, were tested in 11 laboratories. The assays ranged from in vitro tubulin assembly studies to in vivo germ-cell tests. The results allow several conclusions: a) Fungal aneuploidy tests are not capable of detecting inhibitors of mammalian tubulin polymerization such as colchicine and vinblastine. Therefore, they will not play a role in screening for aneuploidy but are of value for studying the relationship between induced aneuploidy and recombination. b) Chemicals that induce aneuploidy in mammalian germ cells are readily detected in the in vitro mammalian cell systems. Some chemicals such as thiabendazole and thimerosal induce aneuploidy in vitro but do not appear to be very effective in vivo. c) Cell division aberrations induced in mammalian cells in vitro seem to be predictive for aneuploidy induction in the same cell type. Likewise, c-mitotic effects and cell cycle delay in vivo in mitotic and meiotic cells correlate with aneuploidy induction in the respective tissue. A second CEC Aneuploidy Program has started recently to refine the most promising test protocols, to provide understanding of variety of mechanisms by which chemicals induce aneuploidy, and to establish a data base for aneugens among environmental pollutants.

Aneuploidy↗

PubMed1992

Sex differences in micronucleus induction with hycanthone methanesulfonate in bone marrow cells of mice.

The clastogenic effect of the antischistosomal drug hycanthone methanesulfonate was studied with the micronucleus test in mouse bone marrow cells. Male and female (102/El x C3H/El)F1 mice were treated with single i.p. injections. Bone marrow was sampled 18, 24 and 30 h after treatment with 100 mg/kg. The highest micronucleus yield occurred at 24 h. The dose response for micronucleus induction at 24 h after treatment was non-linear for doses between 5 and 300 mg/kg. The lowest effective dose was 5 mg/kg for females and 10 mg/kg for males. The experiments revealed a significantly higher sensitivity of female mice for the induction of micronuclei in polychromatic erythrocytes by hycanthone methanesulfonate. This result supports the recommendation to use both sexes for quantitative assessment of genotoxicity in the micronucleus test.

Animals↗

PubMed1992

Aneuploidy induction in mouse spermatocytes.

Assays for aneuploidy are being developed within a coordinated research program sponsored by the Commission of the European Communities. The 10 known and suspect spindle poisons colchicine (COL), econazole (EZ), chloral hydrate (CH), hydroquinone (HQ), diazepam (DZ), thiabendazole (TB), cadmium chloride (CD), pyrimethamine (PY), thimerosal (TM) and vinblastine (VBL) were tested for aneuploidy induction in male germ cells. Two different criteria were used for the evaluation of slides from testicular material of (102/El x C3H/El)F1 mice at different times (6, 14 and 22 h) after treatment with different doses of each of the test chemicals. Secondary spermatocytes of mice were evaluated by chromosome counting to determine the induction of hyperploidy. The proportions of spermatogonial mitoses, first and second meiotic metaphases were determined in order to recognize an effect of the test chemicals on testicular cell proliferation. COL, EZ, CH, HQ and VBL clearly increased the frequencies of hyperploid secondary spermatocytes which indicated non-disjunction induction during the first meiotic division. DZ and CD were less effective but significantly positive (P less than 0.05). Concomitantly, COL, EZ, CH, HQ, DZ, CD and VBL induced meiotic delay in primary and/or secondary spermatocytes. It is concluded that meiotic delay may be indicative for aneuploidy induction and the evaluation of changes in testicular cell proliferation described here could serve as a prescreen and partially substitute the time-consuming counting of metaphase chromosomes in secondary spermatocytes.

Aneuploidy↗

PubMed1992

Telomeric signals in robertsonian fusion and fission chromosomes: implications for the origin of pseudoaneuploidy.

In situ hybridization with synthetic plant telomeric sequences resulted in labeling of all broad bean (Vicia faba) chromosomes at their ends only. Telocentric chromosomes derived by fission of the metacentric satellite chromosome of V. faba also showed signals at both of their ends, whereas the ancestral metacentric did not display signals at its primary constriction, the point of fission. As in V. faba, all acrocentric mouse chromosomes were labeled by in situ hybridization with a vertebrate telomeric probe at both ends of each chromatid exclusively. However, different metacentric Robertsonian chromosomes derived by fusion of defined acrocentrics did not show signals at their primary constrictions. The mechanism of Robertsonian rearrangement leading to a pseudoaneuploid increase or decrease in chromosome number therefore cannot consist solely of a simple fission or fusion of chromosomes without a concomitant gain or loss of chromatin material. The additional assumption of a subdetectable deletion of telomeric sequences after fusion and amplification of these sequences following fission is necessary to explain the present observations.

Aneuploidy↗

PubMed1991

Clastogenic effects of hydroquinone: induction of chromosomal aberrations in mouse germ cells.

The clastogenic activity of hydroquinone (HQ) in germ cells of male mice was evaluated by analysis of chromosomal aberrations in primary spermatocytes and differentiating spermatogonia. In the first experiment with treated spermatocytes the most sensitive stage of meiotic prophase to aberration induction by HQ was determined. Testicular material was sampled for microscopic analysis of cells in diakinesis-metaphase I at 1, 5, 9, 11, and 12 days after treatment with 80 mg/kg of HQ, corresponding to treated diplotene, pachytene, zygotene, leptotene and preleptotene. The frequencies of cells with structural chromosome aberrations peaked at 12 days after treatment (p less than 0.01). This indicates that the preleptotene when DNA synthesis occurred was the most sensitive stage of meiotic prophase. In the second experiment the dose response was determined 12 days post treatment by applying 2 additional doses of 40 mg/kg and 120 mg/kg. The clastogenic effects induced by 40 and 80 mg/kg were significantly different from the controls (p less than or equal to 0.01) and higher than the results obtained with 120 mg/kg of HQ. A humped dose-effect relationship was observed. In a third experiment the same doses were used to analyse chromosomal aberrations in dividing spermatogonia of mice 24 h after treatment with HQ. All the administered doses gave results statistically different from the control values (p less than or equal to 0.01) and the data were fitted to a linear equation. HQ was found to be clastogenic in male mouse germ cells. It is concluded that the clastogenic effect in male germ cells is of the same order of magnitude as in mouse bone marrow cells.

Animals↗

PubMed1991

Mouse micronucleus tests with known and suspect spindle poisons: results from two laboratories.

Micronucleus assays were carried out independently in two laboratories with 10 chemicals selected for aneuploidy studies in a coordinated project supported by the CEC. All chemicals were distributed from a single batch by the project coordinator. Male and female mice were treated by single i.p. injections, bone marrow was sampled 6, 24 and 48 h after treatment. Polychromatic and normochromatic erythrocytes were evaluated for the presence of micronuclei after May--Grünwald/Giemsa or Wright staining. The results from both laboratories are in close agreement even though different stocks of mice and different sample sizes were employed in the two laboratories. Only three of the 10 compounds induced micronuclei in mouse erythrocytes: colchicine, hydroquinone and vinblastine. The other seven chemicals gave negative results: econazole, chloralhydrate, diazepam, thiabendazole, cadmium chloride, thimerosal and pyrimethamine. The negative results for econazole and chloralhydrate were unexpected in light of the fact that these two chemicals were previously shown to increase the mitotic index and to induce c-mitotic effects in mouse bone marrow cells. The need for further investigations of these compounds by chromosome counting in second post-treatment metaphases is emphasized to determine their ability to induce aneuploidy.

Aneuploidy↗

PubMed1991

Classification of micronuclei in murine erythrocytes: immunofluorescent staining using CREST antibodies compared to in situ hybridization with biotinylated gamma satellite DNA.

Micronuclei (MN) in erythrocytes of mouse bone marrow cells were induced in vivo by the spindle poisons colchicine (COL) and vinblastine (VBL), by hydroquinone (HQ) and by the alkylating agent mitomycin C (MMC). Two different methods were applied to detect whole chromosomes with centromeric proteins or chromatin in MN to discriminate between spindle damaging or clastogenic activity of these chemicals. One method determined the fraction of MN with centromeric chromatin by immunofluorescent staining using antikinetochore antibodies (CREST staining). The other method applied non-radioactive in situ hybridization with a novel DNA probe. The fractions of MN that showed positive signals by either technique thus indicating with a high probability the presence of whole chromosomes instead of acentric fragments, were in good agreement for COL, VBL and HQ. After application of MMC, however, 4.5% of the MN were CREST-positive, while 29% gave a positive hybridization signal. The results suggest, that kinetochores may have lost certain centromeric antigens due to treatment with MMC so that MN containing whole chromosomes appear CREST-negative. The presented in situ hybridization scheme using satellite DNA is a more direct detection and is advantageous to the CREST staining technique in that it is unaffected by damage of kinetochore or centromeric function.

Animals↗

PubMed1991

Dose-related clastogenic effects induced by benzene in bone marrow cells and in differentiating spermatogonia of Swiss CD1 mice.

Cancer hazard is due to genotoxic events in somatic cells and genetic hazard in the strict sense is due to mutagenic events in germ cells. The investigation of sensitivity differences between somatic and germinal cells is pertinent to the question whether a genotoxic carcinogen is also a germ cell mutagen. Cytogenetic damage induced by benzene in mice was evaluated by determining the frequencies of chromosomal aberrations in bone marrow and spermatogonial cells of male Swiss CD1 mice. First, the analysis was performed by administering 1 ml/kg (880 mg/kg) of benzene as a single oral dose and sampling either cell type after a wide range of times (6, 12, 18, 24, 30, 36, 42 and 48 h) to determine the time of maximum response. At this dose benzene showed high clastogenic activity in bone marrow cells with a peak between 24 and 30 h. In differentiating spermatogonia the frequency of aberrant cells was highest 24 h after treatment. The overall effect in spermatogonia was lower than in bone marrow cells. Second, the dose response was determined 24 h after treatment with two additional doses of benzene: 0.1 ml/kg (88 mg/kg) and 0.5 ml/kg (440 mg/kg) for bone marrow cells; 0.25 ml/kg (220 mg/kg) and 0.5 ml/kg (440 mg/kg) for differentiating spermatogonia. The clastogenic effect was dose dependent in both cell types. The frequencies of aberrant cells increased in a linear-quadratic manner in bone marrow and linearly in differentiating spermatogonia. Furthermore, the per cell damage was higher in bone marrow than in spermatogonial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

PubMed1991

[A study of aneuploid induction by three mitotic arrestants in mouse bone marrow cells].

Three mitotic arrestants, i.e., colchicine (COL), econazole(EZ) and hydroquinone (HQ) have been assayed by means of C-Mitotic (CM) effects, micronucleus (MN) and chromosomal aberration (CA) test for their effects of aneuploid induction in mouse bone marrow cells COL induced poly/aneuploid in mouse bone marrow cells. EZ was weakly positive in CM effects test but it may not induce aneuploid in mammalian cells. HQ could not only be a clastogen but also an aneuploid inducer. The results indicated that the comparative employment of the three cytogenetic criteria could be quite useful for detecting aneuploidy inducers in mammalian somatic cells in vivo.

Aneuploidy↗

PubMed1990

Clastogenic effects of cis-diamminedichloroplatinum. II. Induction of chromosomal aberrations in primary spermatocytes and spermatogonial stem cells of mice.

The clastogenic effect of the anticancer drug cis-diamminedichloroplatinum (II) (cisplatin) on meiotic prophase in primary spermatocytes and on spermatogonial stem cells of male (101/E1 x C3H/E1)F1 mice was studied. The intraperitoneal doses of cisplatin tested were 5.0, 7.5 and 10.0 mg/kg. Chromosomal aberrations were examined at diakinesis-metaphase 1 of meiosis 1-13 days after treatment, representing cells treated at diplotene, pachytene, zygotene, leptotene an preleptotene. Reciprocal translocations were evaluated 63-70 days after treatment, representing treated stem-cell spermatogonia. Cisplatin had a toxic effect in zygotene to preleptotene of meiosis, as indicated by the significant reduction in testicular weight. At diplotene, pachytene and zygotene no enhancement of aberrations was found. An increase in aberrant cells was observed during leptotene with preleptotene being the most sensitive stage. The dose-response relationship for aberrant cells was linear on day 13 after treatment. It is concluded that, like mitomycin C (Adler, 1976), cisplatin primarily caused aberrations during the premeiotic phase of DNA synthesis. No significant increase of translocation multivalents was found after treatment of stem-cell spermatogonia.

Animals↗

PubMed1990

Clastogenic effects of known and suspect spindle poisons studied by chromosome analysis in mouse bone marrow cells.

The present study was performed within the project 'Genomic Mutations' (sponsored by the Commission of the European Communities) in order to gather all possible experimental information on 10 chemicals selected on the basis of their possible capacity to induce aneuploidy. An analysis of chromosomal aberrations was carried out in bone marrow cells of mice with the first five chemicals: colchicine (COL), econazole (EZ), chloralhydrate (CH), hydroquinone (HQ) and diazepam (DIAZ). The experiments were performed in parallel to micronucleus tests with the objective to distinguish a positive micronucleus response due to chromosomal breakage from that obtained by lagging chromosomes. The results of the micronucleus tests will be reported elsewhere. COL, CH, EZ and DIAZ showed no clastogenic effects in mouse bone marrow cells after single intraperitoneal injection. Polyploid cells were significantly more frequent after COL treatment. HQ showed a dose-dependent induction of chromosomal aberrations at 6 and 24 h after treatment. After 24 h, cells with multiple aberrations up to complete chromosome fragmentation were frequently observed. They indicate that a small fraction of the cell population, probably related to a specific stage of the cell cycle, was particularly sensitive to HQ. A sex difference in clastogenic response to HQ was not observed. It is concluded that of the five chemicals tested only HQ was clastogenic in mouse bone marrow cells under the present experimental conditions.

Aneuploidy↗

PubMed1990

Application of antikinetochore antibody staining (CREST staining) to micronuclei in erythrocytes induced in vivo.

Micronuclei (MN) can be formed by acentric chromosome fragments or whole lagging chromosomes. In order to discriminate MN produced by chromosome breakage from those arising from spindle malfunction a staining method using immunofluorescent kinetochore antibodies has been applied successfully in vitro. In the present study MN in polychromatic erythrocytes of mouse bone marrow cells induced in vivo by the spindle poison colchicine (COL) and the clastogen mitomycin C (MMC) were analysed after CREST staining. The staining method was modified by using pretreatment with detergents in order to allow a good penetration of the antibodies into the MN. About 66% of the MN induced by COL in contrast to only 4.5% of the MMC induced MN were CREST-positive. The preliminary results show that the CREST staining is also in MN induced in vivo capable of detecting the origin of MN and to discriminate between the spindle damaging or clastogenic activity of environmental agents. The method described will give supplementary information about MN, it cannot substitute for the common micronucleus test.

Alkylating Agents↗