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O Chlebovský

Publications and source records attributed to O Chlebovský.

At least 19 recordsLinked to original sources
PubMed2002

Autoradiographically detected impairment of RNA synthesis pattern in 8-16 cell bovine embryos after irradiation.

Early preimplantation bovine embryos at 8- or 16-cell stage were analysed by [5-3H]uridine autoradiography for distribution of newly synthesized RNA after 60Co irradiation with a single dose of 1 Gy, 2 Gy or 4 Gy gamma rays, respectively. Embryos irradiated with a single dose of 1 Gy showed equally decreased synthesis of RNA in nucleoplasma as well as in nucleolus. In embryos irradiated with a single dose of 2 Gy or 4 Gy, RNA synthesis was decreased and localized mostly on the periphery of the nucleus; in both cases of irradiation, the nucleus center being without labelling. In most of embryos irradiated with a dose of 4 Gy, the nucleoli were not labelled, and an increasing occurrence appeared of various nucleus chromatin segregation forms, mainly as its marginalization.

Animals↗
PubMed2001

Detection of genome impairment in bovine early embryos by autoradiography: a methodological note.

The applicability of Pavlok's method characterising the nuclear status of early preimplantation bovine embryos by nuclear labelling pattern after a short pulse of [5-3H]uridine (revealing in situ detection of RNA transcription at the onset of the major embryonic transcription) was tested on experimentally irradiated 8- to 16-cell bovine embryos. After [5-3H]uridine labelling the semi-thin sections of these embryos were analysed by autoradiography for intranuclear distribution of newly synthesised RNA expected to be influenced by increasing doses of irradiation by gamma rays from a 60Co source. In control embryos, the labelling was homogeneously distributed in nucleoplasm and in nucleoli. The expected effects were clearly detected already in embryos irradiated with a dose of 2 Gy, in which low-level RNA synthesis was localised mostly at the periphery of the nucleus, the nuclear centre being without labelling. A detailed analysis of consecutive sections of embryos from all groups of irradiated and control embryos, using an arbitrary scale considering these effects, confirmed the detectability of the threshold level of genome impairment.

Animals↗
PubMed2000

Influence of age and K, Mg aspartate (Cardilan) on murine haemopoiesis.

We have studied the effect of age as well as the effect of short-term and long-term intake of K and Mg salts of aspartic acid (Cardilan) on haemopoiesis in ICR mice strain. The cellularity of the bone marrow does not change with aging, but the number of granulocyte-macrophage colony-forming cells (GM-CFC) and also the number of spleen colony-forming units (CFU-S) and erythroid burst-forming units (BFU-E) in two-year-old mice increased in the bone marrow. In two-year-old mice the number of leukocytes decreased in the peripheral blood with aging, mainly as a result of a decrease in mononuclear cells. Short-term drinking (STD) of Cardilan caused increased numbers of CFU-S and BFU-E in bone marrow and increased numbers of reticulocytes in the peripheral blood of one-year old animals (STD/12 months old). In the oldest mice (STD/24) increased weight and cellularity of the spleen and rapid increase of leukocytes and reticulocytes in the peripheral blood was recorded. After long-term drinking (LTD) of Cardilan the number of spleen GM-CFC rose markedly in one-year-old mice (LTD/12) and in two-year-old mice (LTD/24) the number of reticulocytes in the peripheral blood rose. Our results indicate that K and Mg salts of aspartic acid influence erythropoietic activity most widely.

Aging↗
PubMed1999

Favourable effect of K, Mg aspartate on serum proteins in aging rats.

The serum concentration of individual proteins in aging rats was studied. We have made an attempt to slow down the changes in concentration occurring in rats from 5 up to 17 months of age by application of aspartate given in drinking water containing 500 mg% of monopotassium DL asparagicum and 500 mg% of monomagnesium D,L asparagicum. The solution was administered continuously for 14 days a month for 1 year. In a part of animals, the aging process was accelerated by ionizing radiation with a single dose of 4.0 Gy. We found out that administration of aspartate caused slowing of changes in concentration of all proteins observed (prealbumin, albumin, A1-globulin, haptoglobin and hemopexin) in non-irradiated and prealbumin, albumin, A1-globulin in irradiated rats in comparison with the values of proteins in rats drinking water only. The preparation did not influence more significantly the changes in the serum concentration of haptoglobin and hemopexin in rats whose aging was accelerated by radiation. A favourable effect of the preparation used manifested also in the values of survival, because the animals protected with K, Mg aspartate survived by 25-30% longer.

Aging↗
PubMed1989

The effect of indomethacin on nucleic acids in blood, hemopoietic and lymphoid tissues in continuously irradiated rats.

The effect of indomethacin--a nonsteroid antiinflammatory drug with potential antitumor activity--on the development of radiation-induced changes was followed in blood, bone marrow, spleen, thymus and testes of rats. Indomethacin administered in drinking water (0.7-1.0 mg/kg per day) during a continuous 7-day irradiation with gamma rays (dose rate of 2.055 Gy/day, total accumulated dose of 14.385 Gy) caused a higher and more rapid incorporation of 3H-thymidine into blood DNA, and an increase in blood RNA concentration. The results suggest some stimulation of hemopoiesis recovery by indomethacin treatment in continuously irradiated rats.

Animals↗
PubMed1989

The effect of indomethacin on serum proteins in continuously irradiated rats.

Changes in serum albumin, A1-globulin, A1-macroglobulin, haptoglobin, hemopexin, and ceruloplasmin concentration in rats irradiated continuously with a daily dose of 2.055 Gy up to a total dose of 14.385 Gy of gamma rays after peroral indomethacin administration were followed by two-dimensional immunoelectrophoresis. The use of indomethacin evoked a beneficial response particularly in the serum concentration of albumin, A1-globulin, and A1-macroglobulin on the 21st day after irradiation. In contrast with the concentrations in the irradiated control group, protein values in rats treated with indomethacin were less reduced. We did not observed significant differences between the serum concentration of haptoglobin, hemopexin, and ceruloplasmin of irradiated, indomethacin-treated and irradiated control, up to the 58th day after irradiation.

Alpha-Globulins↗
PubMed1989

Changes of the peripheral blood picture after combined neutron and gamma irradiation.

Changes of the peripheral blood picture of rats irradiated with a single dose of 2 Gy of neutrons were followed in comparison with a group of rats irradiated with a single dose of 2 Gy of neutrons followed by continuous gamma irradiation (daily dose rate 0.574 Gy, total dose 6 Gy). The decisive factor for the organism damage was the single 2 Gy neutron dose. The subsequent continuous gamma irradiation retarded the reparation of the peripheral blood elements.

Animals↗
PubMed1989

Serum proteins in rats after combined neutron and gamma irradiation.

Quantitative changes of some selected serum proteins in rats irradiated with a single dose of 2 Gy neutrons were compared with protein changes in rats irradiated with an equal single neutron dose and subsequent continuous gamma irradiation using daily dose rate of 0.574 Gy up to the total dose of 6 Gy. On the basis of the values obtained from the diagrams of two-dimensional immunoelectrophoresis it was found that both irradiations entailed approximately equal quantitative changes of the serum concentrations of the proteins followed. The differences found concerned time intervals of the adjustment of the changes produced. After neutron irradiation reparation of the serum albumin occurred on 14th day, of A1-globulin concentrations on 28th day and of haptoglobin on 90th day, yet after combined neutron and gamma irradiation reparation of the changes in albumin on 15th and A1-globulin occurred on 40th day and in haptoglobin only on 100th day after neutron irradiation.

Animals↗
PubMed1986

Serum proteins in rats irradiated continuously over a long period at diminishing radiation dose rates.

The authors studied changes in serum protein concentrations in rats exposed 10 days to continuous irradiation at progressively diminishing dose rates imitating the radioactive decay of a fissile mixture, up to a total dose of 9 Gy, both during and up to 240 days after discontinuing irradiation. The prealbumin concentration (from the 6th day) and the A1-globulin concentration (from the 1st day) fell to 70% during irradiation. Afterwards, the A1-globulin level fell significantly up to the 28th day and then, from the 60th to the 240th day, rose again. During irradiation the serum haptoglobin concentration rose significantly from the 1st to the 10th day and the ceruloplasmin concentration on the 10th day. An increase in both protein concentrations (to 172% and 190%) was also observed on the 14th postirradiation day, after which the serum haptoglobin, ceruloplasmin and A1M concentration fell abruptly up to the 60th day.

Animals↗
PubMed1983

[Karyometric changes in the neurons of the hypothalamic and ependymal nuclei of the 3d cerebral ventricle in sheep after administration of Gn-RH and subsequent irradiation].

Caryometric analysis was used for the study of changes in the cell nucleus volume of the neurons of nucleus paraventricularis, nucleus arcuatus, and ependyma of the third cerebral ventricle of sheep after the administration of Gn-RH, followed by exposure to X-rays. The test animals were 12 ewes in physiological anoestrus and two rams. The trials were conducted in spring. The first group of four sheep and two rams were left as controls; in the ewes of the second group the hypothalamo-hypophysial region was irradiated by exposure to 516.5 mC/kg (200 R); in the four ewes of the third group, ovaries were directly irradiated at laparotomy by exposure to 64.4 mC/kg (250 R). The ewes of the second and third group were treated with an i. m. administration of 400 micrograms Gn-RH per head before irradiation. The excisions were collected and processed the tenth day from irradiation. The studied material was fixed by injection of 10% formalin and finished by another dose of 10% formalin after the excision of the brains. The paraffin slices were stained with haematoxylin-eosine. The caryometric analysis was performed at 3000-fold magnification, 200 cells being measured in each sample. Changes in neurosecretory cells were described in the regions of nucleus paraventricularis, nucleus arcuatus and in the ependyma of the third cerebral ventricle. The results of the caryometric analysis of nucleus paraventricularis and nucleus arcuatus suggest that the administration of Gn-RH and irradiation of the hypothalamo-hypophysial region, and direct irradiation of ovaries, stimulate the studied cerebral structures. The changes observed in the ependyma of the third cerebral ventricle after the administration of Gn-RH and subsequent irradiation of the hypothalamo-hypophysial region are insignificant; it is only after the direct irradiation of ovaries that these cells are inhibited by an indirect effect through the feedback mechanism.

Animals↗