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I Kalina

Publications and source records attributed to I Kalina.

71 records · Page 4Linked to original sources
PubMed1979

The frequency of chromosomal aberrations in long-term irradiated mice and rats.

The frequency of chromosomal aberrations was studied in myelokaryocytes of mice and rats continuously irradiated for 90 days at a dose rate of 50R/day. The curves expressing the frequency of chromosomal aberrations in continuously irradiated mice and rats are biphasic. The first phase is similar for the two species and is characterized by an increase in the frequency of cells with chromosomal aberrations. In the second phase, the frequency of cells with chromosomal aberrations had stabilized at a level of 25--28% in rats, and in mice the values of aberrant cells were gradually increasing until the end of irradiation when they reached 40.1%. In contrast to it, the distribution of aberrations of the chromatid and chromosomal types did not change throughout the experiment in both animal species.

Animals↗
PubMed1979

[Cytogenetic changes in the bone marrow cells of long-term irradiated rats].

The occurrence and characteristics of the chromosome structural changes in femur bone marrow cells under continuous irradiation with the exposure rate of 50 R/day within 90 days was followed. The 25% increase in the chromosome aberration frequency was observed within 7 days of the irradiation, and then the aberration rate was constant up to the end of the irradiation (90 days).

Animals↗
PubMed1978

Changes in the recovery ability of colony-forming units after continuous irradiation.

The recovery ability of colony-forming units from mice continuously irradiated for 30 and 100 days at an exposure rate of 25 and 50R/day was investigated. The rate of recovery depended not only on the daily exposure but also on the total dose accumulated. The course of the recovery process was assumed as follows: B(t) = Bs + (Bo--Bs). (formula:see text) was characterized by calculating the estimate(s) of the recovery coefficient tau.

Animals↗
PubMed1977

Effect of different daily rate of continuous irradiation upon changes in cfu number.

The effect of continuous irradiation upon colony-forming capacity of bone marrow cells was studied in mice exposed continuously for the length of 130 days to ionizing radiation at exposure rates ranging from 1--50R per day. A stabilized state in CFU number was observed between days 30 and 100, its level being related solely to the daily exposure rate. An interpolation of data on CFU found on days 30, 40, 50, 60, 70, 80, 90, and 100 provided an exponential curve which can be characterized by the equation log y = a + bx + cx2. This equation can be applied to prognostic estimation of CFU level during the stabilized state between days 30 and 100 of continuous radiation exposure at rates ranging from 1--50R day.

Animals↗
PubMed1975

Effect of continuous irradiation upon bone marrow haemopoietic stem cells in mice.

The effect upon the stem cells in mouse bone marrow of continuous irradiation at different daily exposure rates ranging from 1R--1,000R was investigated by means of the exogenous spleen colony assay. At exposure rates between 1 and 50R/day, a stabilized state in the CFU value becomes established, its level decreasing with the increase in the daily exposure. Exposure rates between 80 and 1,000R/day lead to an initial steep, but later on flatter, decrease in CFU number until death of the animals. Mass deaths occur in mice when the CFU number falls below 5%. The results further delimit the range of exposure doses for which a dependence was found of the CFU number upon the total exposure dose of continuous radiation.

Animals↗
PubMedDate not supplied

Germ line polymorphisms of the tumor suppressor gene p53 and lung cancer.

Two p53 variable sites (BstUI and MspI SNPs in exon 4 and intron 6, respectively) and their haplotype combinations were studied in 109 patients (84 males and 25 females) with lung cancer and 113 healthy controls from the region of Eastern Slovakia. There were no differences found between lung cancer patients and controls carrying the distribution of p53 BstUI and MspI alleles. However, the genotype distribution showed a significantly higher proportion of MspI heterozygotes in lung cancer patients (P=0.048, OR 1.83, 95% CI 1.00-3.34) than in controls. The analysis based on haplotype frequencies showed the presence of BstUI-MspI 2-1 haplotype in cancer patients (5.4%) in contrast to the absence of this haplotype in healthy controls. The results of this study suggest that the p53 MspI polymorphism may modify the susceptibility to lung cancer as a single factor rather than in combination with BstUI polymorphism.

Adult↗
PubMedDate not supplied

Experimental attempts to extend the current preimplantation genetic diagnosis with individual karyotypization of human blastomeres.

The drug-induced chromosome condensation using okadaic acid, a potent protein phosphatase inhibitor, was studied in day 1 to day 4 (D1-D4) spare human preimplantation embryos. In order to obtain cells for genetic tests, we developed a modified displacement blastomere biopsy method. During the okadaic acid treatment, approximately 40% of biopsied cells were lost due to heavy changes of the plasma membrane; this detrimental effect of okadaic acid differed markedly with the respect to the age of embryos. In comparison with the natural embryonic mitotic index, day 1 and day 2 embryonic cells gave increased yields of chromosome spreads (up to 51% of the initial D1-D2 cell number); on days 3 and 4 we were not able to obtain from surviving cells more than 31% blastomeres with condensed chromosomes (9% of total D3-D4 cell number). All chromosome spreads were successfully used for recycling in G-banding and subsequent FISH analysis.

Biopsy↗