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G Ertsgreber

Publications and source records attributed to G Ertsgreber.

6 recordsLinked to original sources
PubMedDate not supplied

[Effect of gamma-irradiation and neutrons on DNA-membrane complexes in mammalian cells].

The first results of the radiobiological studies obtained in a biophysical channel of the IBR-2 reactor at the Joint Institute for Nuclear Research are presented in this report. A study was made of the DNA-membrane complex sedimentation after exposure of Chinese hamster cells V79-4 to gamma-rays within a wide range of doses. The assumption, that had earlier been forwarded by the authors, of the role of double-strand DNA breaks in the alteration of a relative rate of the complex sedimentation upon irradiation of cells with doses above 50 Gy was confirmed.

Animals↗
PubMedDate not supplied

[Damage by gamma rays and heavy ions to superhelical structures of nuclear DNA].

Chinese hamster cells (V79-4), human lymphocytes and mouse ascites cell were exposed to gamma-rays and heavy ions (4He and 12C). Sedimentation of complexes containing DNA was studied after cell lysis by centrifugation in a neutral sucrose gradient. The distinctions noted after irradiation with gamma-rays and heavy ions are consistent with the idea of the superhelical organization of DNA into discrete and membrane-bound compact units. According to the estimates made the diameter of these complexes was approximately 0.2 micron and DNA content, about 2 X 10(9) dalton.

Animals↗
PubMedDate not supplied

[Use of multicellular spheroids in studies based on the NSD (nominal standard dose) concept].

The authors discuss the possibility of application of multicellular spheroids as a model system in studies based on NSD conception. The death rate of spheroids from cells of Chinese hamster V79-4 was shown to depend upon cumulative dose of gamma- and neutron (0.7 MeV)-radiation (the number of fractions was 1, 5 and 10). With fractionated irradiation, the reoxygenation effect was observed. A good coincidence was obtained between the dependence of the cumulative dose upon the number of fractions for multicellular spheroids and clinical data.

Animals↗
PubMedDate not supplied

[Double-stranded DNA breaks and inactivation of mammalian cells in relation to the LET of the radiation--comparison between experiment and theory].

In experiments on Chinese hamster cells the survival curves and the yield of double-strand DNA breaks were determined after irradiation at different LET. The comparison of the experimental results and the survival curves calculated on the basis of Günter-Schultz's theory of radiation inactivation of cells has demonstrated that radiation-induced double-strand DNA breaks are responsible for the lethal effect of radiation on cells.

Alpha Particles↗
PubMedDate not supplied

[Multicellular spheroids for use in radiobiological experiments].

Cell spheroids are conglomerates of closely arranged cells with reciprocal effects among them. Spheroids are histologically similar to nodulary tumours. Cells constituting these spheroids are heterogenous in their sensitivity to X-rays and fast neutrons. Radiosensitivity of cells in a small spheroid is lower than that of similar cells grown in a monolayer.

Cell Survival↗