Cytogenetic Studies of the Leukocytes of Couples with Habitual Abortions

Karyotypes were prepared from peripheral blood leukocytes in 18 couples with his-tories of habitual abortions. The Standard chromosome analysis and G-banding techniques were studied. The abnormal karyotypes seen were one case with 20% of 45, XX, -14, -15, t(14/15), one case of 46, XY/45, XY, -21 mosaicism, one case of 45, XX, -14, -21, t(14/21), one case of 46, XX/45, XO mosaicism and one case of 46, XYq+. Many other types of chromosomal abnormalities from many reports in couples with spontaneous abortions are discussed.

The Production of Micronuclei from Chromosome Aberrations by Chemical Carcinogens in Mice

The effect of four alkylating agents (MMS, EMs, DMN, DEM), under various con centrations on mouse bone marrow erythrocytes, were studied by means of the micronucleus test. The results obtained were as follows: 1) The lethal doses on mice were MMS = 130 mg/kg/bw, EMS = 300 mg/kg/bw, DMN = 50 mg/kg/bw and DEN = 70 mg/kg/bw. 2) Micronuclei were easily seen and in different controls the micronulei were found a little over 0.1%. 3) The dose-effect relationship was obtained. In the MMS and EMS treated groups, incidences of micronulei were 0.45 to 2.56% and 0.4 to 2.1% respectively. 4) In the DMN and DEN treated groups, incidences varied between 0.15 to 0.90 % and 0.2 to 1.02% respectively. 5) Four alkylating agents were compared and discussed with respect to micro nucleus production from chromosomal aberrations.

Cytogenetic Analysis of Conceptus Material of Korean Women at First Trimester

No abstract available.

Detailed Analysis of Chromosome Aberrations in Human Leukocyte Induced by Anti-malignant Tumor Agent (FT-207)

The anticancer agent's FT-207, N1-(2'-tetrahydrofuryl)-5-fluorouracil, a derivative of 5FU (5-fluorouracil), induced chromosome damage to the human leukocyte was investigated. FT-207 inhibit mitosis and cause chromatid and chromosome breakage and chromatid exchange with 20 ug/ml for 48 to 72 hours of treatment. However, with 15 ug/ml for 72 hours only delayed spiralization was produced in some of the chromosomes in the same cells. The random distribution of chromosome breakage were observed and the effect of FT-207 on the chromosomes of human leukocytes were time dependent rather than concentration dependent. The comparision of the effect of mitomycin C on human leukocytes and the action of FT-207 at specific times during the cell cycle were discussed.

Cytogenetic Studies of Peripheral Leukocytes following Surgery and Radiotherapy in Patients with Breast Carcinoma

Chromosome analysis were carried out on peripheral blood leukocytes of breast cancer patient during the irradiation therapy after unilateral simple mastectomy. The observations were made at intervals varying from one to 5 weeks during the therapy and one month after the completion of tile treatment. During the first and second weeks of treatment normal metaphase was noted and during the 4th and 5th weeks, there were no mitotic figures from the cell population. The chromosomal aberrations found after 3 weeks of treatment were, 11% of simple chromatid breaks, 7% of chromatid interchanges (translocations) and 8% of fragments. One month after the completion of the course of treatment showed a return of mitosis and that total chromatid breaks had decreased to 5%. Radiation effects on cell division and chromosome aberration are discussed.

The Effect of Mitomycin C on Human Chromosomes with G-banding Patterns

Mitomycin C was introduced to human leukocyte cultures to investigate the analysis of chromosome aberration by G-banding patterns. The relationship between mitomycin C and secondary constriction; length of treatment and exposure time of the compound; and G-banding pattern were discussed. The results are summarized as follows: 1. The mitotic rate of cultures exposed to mitomycin C at a concentration of 0. 1 microgram/ml for 24 hours did not inhibit significantly compared with that of the control, and chromosome aberrations were relatively very low. However, the mitotic index of cells exposed to 1.0 microgram/ml for 1 hour or 24 hours was significantly below the control index and a relatively high number of aberrations were found. With the concentration of 0.5 microgram/ml for the last 24 hours of cultural incubation, there was little inhibition of mitotic activity and the highest frequency of observable aberrations were found. Thus, in this study, treatment of the concentration of 0.5 microgram/ml for the last 24 hours of cultures proved to be the most efficient combination for examining the effect of this compound on human leukocyte chromosomes. 2. Mitomycin C did not appear to break the chromosome randomly. More than half of the aberrations were of the interchange type which were in most cases involved with chromosomes 1, 9 and 16. They are joined in, at least, the secondary constrictrion regions of one of these chromosomes. The secondary constriction regions contain 60 to 70 percent of the total breaks of each of these chromosomes. The other types of chromosome aberrations were simple chromatid and chromosome breaks at the interband of G-bands and translocations. The frequent association of satellites with 2 to 5 acrocentric chromosomes was also observed. In conclusion, it can be stated that mitomycin C is very specific in causing lesions to appear at the secondary constriction of human chromosomes 1, 9 and 16. The dosage of mitomycin C, length of treatment and exposure time during the culture period are very important factors for induction of chromosome abnormalities, which vary with the individual's leukocytes that have different genetic constitutions.

Cytogenetic Studies of the Korean Chipmunk, Eutamias sibiricus asiaticus

The karyotype of the Korean chipmunk, Eutamias sibiricus asiaticus, was identified and G-banding patterns were demonstrated fer the first time. The diploid number was 38. The autosomes consisted of 4 pairs of metacentrics, 3 pairs of submetacentrics, 4 pairs of subtelocentrics and 7 pairs of acrocentrics. The X chromosome is the second largest in the submetacentric. The Y chromosome is the smallest submetacentric. The present study confirmed and identified Eutamias sibiricus asiaticus as the Korean chipmunk.