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Biomedical subjects

A Basler

Publications and source records attributed to A Basler.

33 records · Page 2Linked to original sources
PubMed1980

Vinyl chloride: an example for evaluating mutagenic effects in mammals in vivo after exposure to inhalation.

As part of a programme of investigations on the mutagenic effects in mammals in vivo after inhalation of environmental chemicals, the effects of the industrial compound vinyl chloride (VC) was analysed. Chinese hamsters were exposed to 1.25%, 2.5% or 5% (v/v) VC in air for 6, 12 or 24 hr. Bone marrow chromosomes were analysed for induced chromosome aberrations and sister-chromatid exchanges (SCEs) 26 h after beginning of exposure. The frequency of VC-induced chromosome aberrations and SCEs both depend on dose and length of exposure. The highest measured effects were 33.25 SCEs/ cell after an exposure to 2.5% VC for 24 h and 25.7% metaphases with aberrations, when exposed to 5% VC for 24 h.

Animals↗
PubMed1980

Testing propafenone hydrochloride in the Ames Salmonella microsome system and in mammalian cytogenetic systems (bone marrow, spermatogonia).

2'-(2-Hydroxy-3-propylaminopropoxy)-3-phenyl-propiophenone-hydrochloride (propafenone-HCl, Rytmonorm) was tested for mutagenic activity in the Salmonella microsome system (Ames test) and in mammalian cell systems. Neither in the Ames test (62.5-1000 microgram/plate) nor in the bone marrow cells and spermatogonia of Chinese hamster (injected doses: 1.57, 3.13, 6.27 mg/kg) there is any evidence for an enhancement of mutation frequencies or chromosome aberration rates. Also, the micronucleus rates were in the control range. Under the experimental conditions of this investigations propafenone-HCl was not mutagenic.

Animals↗
PubMed1979

Cytogenetic effects of busulfan in vivo on bone marrow cells and oocytes of adult mice and liver cells of transplacentally exposed embryos.

Adult female mice were twice treated orally with 15, 30, or 60 mg busulfan per kg of body weight. In bone marrow, a dose-dependent linear increase in the frequency of chromosome aberrations was observed. Similar to the effects of other alkylating agents, busulfan induced all types of aberrations, including exchanges. In metaphase II oocytes, only a few chromosome aberrations were observed. An intervening round of DNA-replication seems to be necessary to translate busulfan-induced lesions in oocytes into chromosome aberrations. In embryonic liver cells of transplacentally exposed mice, chromosome aberrations were induced.

Animals↗
PubMed1979

Effects of caffeine on sister-chromatid exchanges (SCE) in vivo.

Chinese hamsters were twice treated with caffeine via stomach tube. The single doses were either 20, 100, 200 or 400 mg per kg body weight. A dose-dependent increase was observed in the frequencies of SCE induced in vivo in bone-marrow cells. Two intraperitoneal injections of the chemical mutagens, cyclophosphamide or benzo[a]pyrene, led to a pronounced increase of the frequency of SCE. Simultaneous applications of the chemical mutagens and caffeine decreased the rate of SCE. The effect of caffeine per se to induce SCE, and the mechanisms by which caffeine reduces the level of SCE induced by chemical mutagens are discussed.

Animals↗
PubMed1979

Mutagenicity of polycyclic hydrocarbons. V. Induction of sister-chromatid exchanges in vivo.

The potency of polycyclic hydrocarbons to induce SCEs in vivo was analysed. The most potent SCE-inducing compound was benzo[a]pyrene. Benzanthracene, benzo[b]fluoranthene, benzo[e]pyrene, phenanthrene, chrysene and dibenzanthracene enhanced the SCE frequency to a smaller extent. The number of anthracene-induced SCEs per metaphase was not increased as compared with the controls.

Animals↗
PubMed1978

Timing of meiotic stages in oocytes of the Syrian hamster (Mesocricetus auratus) and analysis of induced chromosome aberrations.

The stages of maturation of oocytes (meiotic stages) in adult Syrian hamsters (Mesocricetus auratus) have been timed following superovulation treatment. Timing and superovulation were induced by an injection of pregnant mares' serum on the first morning of the estrus cycle, followed by injection of human chorionic gonadotropin (HCG) in the evening of the fourth day. The oocytes completed the prophase of the first maturation division 3 h after the injection of HCG. Ovulation began 9 1/2 h after the injection. A method of analysis of metaphase II chromosomes of Syrian hamster oocytes 16 h after injection of HCG is described. This method seems to be appropriate for the examination of the induction of genetic defects during oogenesis. Female hamsters were treated with 2,3,5-triethyleneimonobenzoquione-1,4. The induced chromosome aberrations were analysed. Dosis-dependent response could be demonstrated.

Animals↗
PubMed1977

Comparative investigations with trypaflavin in metaphase-II oocytes and in dominant lethal assay.

Pregnant C3H mice were orally treated with 50 mg Trypaflavin/kg on day 7, 11, 14, or 15 post conception. The embryos were thus treated in utero with the test compound. At the age of 10 weeks, the dominant lethal assay was performed with F1 females. Dominant lethal mutations were induced only in those mice treated in utero on day 7 of the prenatal stage. Female C3H mice were chronically treated with Trypaflavin (50 X 2 mg/kg/day; dissolved in drinking water). These mice were caged with untreated males. The percentage of preimplantation egg loss and the yield of dead implants per female was increased. Female NMRI mice were chronically treated with Trypaflavin (50 X 2 mg/kg/day by stomach tube). In metaphases II of unfertilized oocytes, the yield of all observed aberration types (aneuploidies, gaps, satellite associations, breaks and fragments, deletions, and interchanges) was increased weakly.

Acridines↗
PubMed1977

Cyto-enetic investigations of mammals. Comparison of the genetic activity of cytostatics in mammals.

Mutagenicity tests have been performed with CP, IP and TP. There is an increase of mutagenic activity from TP to IP to CP 8 h after the second intraperitoneal application. This has been confirmed by analysis of bone marrow chromosomes of mice, rats and Chinese hamsters. The maximum mutagenic activity of all three cytostatics was found 12 h after the second injection. Thereafter the aberration rate induced by CP decreased quickly. The inactivation of IP and TP and the elimination of chromosome aberrations was delayed. Dose-effect-relationships of CP in Chinese hamsters were investigated using the micronucleaus test and analysis of bone marrow chromosomes. Correlations between the two test systems could be demonstrated. Five applications of CP led to a drastic increase of chromosome aberrations in bone marrow of Chinese hamsters. In spermatogonia, on the other hand, no significant increase was detectable. These differences are being discussed.

Animals↗
PubMed1977

Mutagenicity of polycyclic hydrocarbons. II. Monitoring genetical hazards of chrysene in vitro and vivo.

Mutagenicity tests were performed with chrysene in the Salmonella/microsome test, NMRI-mice oocytes, bone-marrow cells and spermatogonia of Chinese hamsters. Only in mice oocytes was a weak but significant increase of structural chromosome aberrations observed. Correlations were found between weak carcinogenic and observed weak mutagenic activities of chrysene in vitro and in vivo.

Animals↗
PubMed1977

Culture of pre-implantation Chinese hamster (Cricetulus griseus) embryos in vitro.

Pre-implantation embryos from Chinese hamsters (Cricetulus griseus) were cultivated under completely defined conditions. The embryos were placed in drops of chemically defined medium under liquid paraffin and cultured in an atmosphere of 10% CO2 in air. By this method, development will proceed in vitro from the two-cell stage up to the blastula within 72 h. It is possible to stop the cultivation at different stages of development, to fix the embryos and analyse the chromosomes. The method described in detail seems to be appropriate for examination of the induction of genetic defects during the first days of embryogenesis.

Animals↗
PubMed1976

Elimination of spontaneous and chemically induced chromosome aberrations in mice during early embryogenesis.

NMRI mice (female female) were treated with 0.25 mg/kg body weight Trenimon (2,3,5-triethyleneiminobenzoquinone-1,4) in the preovulatory phase just before ovulation. Then they were mated with untreated males. The female mice were dissected 45 h after application of this mutagen. The preimplantation embryos, being in a 2-cell stage, were flushed out of the oviduct and cultured in vitro for 60 h. Of the cultured embryos 87.7% reached the blastocysts stage in the control series, whereas only 49.7% did so in the experiments. Some of the females were dissected on the 14th day post conception (p.c.) and the number of dead and living implants was determined. Furthermore, the 9.5- and 13.5-day-old embryos were cytologically investigated, to determine the frequency of chromosomal aberrations. Of the unfertilized oocytes 76.2% deriving from mice treated with 0.25 mg/kg Trenimon, were aberrant in the stage of metaphase II (Röhrborn and Hansmann, 1971). Comparing Röhrborn's and Hansmann's results (1971) to our own findings a continuous elimination of chromosome aberration is clearly to be seen during early embryogenesis. The biological selection takes place in the pre- as well as in the early and late postimplantative phase.

Abortion, Spontaneous↗