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V Svoboda

Publications and source records attributed to V Svoboda.

At least 55 records · Page 3Linked to original sources
PubMed1982

Some quantitative micromorphological characteristics of granulocytic leukemia in 239Pu-injected mice and untreated controls.

Cytologic and histologic evaluation of granulocytic leukemia was carried out in 22 plutonium-treated mice and in 17 controls. The contaminated animals were injected i. v. with 5.4 kBq 239Pu/mouse (180 kBq/kg) at the age of 70 days. Morphologic evidence of the disease was based on the identification of immature abnormal granulocytes in the bone marrow and spleen and on the histologically ascertained leukemic infiltration at least in one of the tissues examined (liver, lung, kidney, lymph nodes). Whatever further symptoms are thought to be of non-specific value. The leukemic process could be mostly evaluated as more florid in the spleen than in the bone marrow. The less active leukemic proliferation in 239Pu-treated mice than in diseased controls is the most important finding of this study. The results are discussed.

Animals↗
PubMed1982

Intensified proliferative activity of the CFU-S in vertebral bone marrow of 239Pu-treated mice as one of the factors involved in the induction of granulocytic leukemia.

Using the exocolonizing test, 59Fe-utilization technique and classical cytology, the authors observed 210 days after i.v. injection of 166.7 kBq of 239Pu/kg in about 30% of contaminated mice a proliferative activity in vertebral bone marrow, characterized with high relative numbers of pluripotent hemopoietic stem cells, significantly higher than in the seriously damaged vertebral bone marrow of the other 239Pu-treated mice and even higher than in the untreated corresponding controls. Simultaneously, the amount of cells in the granulocytic series was increased. After the transplantation to the heavily irradiated syngeneic hosts the stem cells differentiated into splenic colonies with higher iron utilization than in corresponding controls. Higher numbers of mature granulocytes were also found in the peripheral blood and spleen. The authors assume that this activity was an inadequate reparative response of the hemopoietic stem cell compartment to the damaging effect and they consider it to be the critical phase which not only preceded the induction of granulocytic leukemia but also afforded conditions favorable for leukemic transformation of the hemopoietic stem cells.

Animals↗
PubMed1981

Myeloid leukemia 239Pu-treated mice.

Incidence of myeloid leukemia was studied in 79 mice injected i.v. with 180 kBq 239Pu/kg. Plutonium-treated mice were compared with 70 controls of the same origin and sex (random-bred ICR-SPF female mice). The animals were killed moribund and the disease was diagnosed on the basis of histological and cytologic examination of bone marrow, spleen, liver, peripheral blood, and other tissues. It has been found that 22 plutonium-treated mice (27.8%) and 17 controls (24.3%) were leukemic. The mean survival of diseased animals was 459 +/- 19 days in the tested group and 559 +/- 24 days in controls. It means that the occurrence of myeloid leukemia was not very different in irradiated and control mice, but under plutonium contamination the disease appeared significantly earlier and its incidence was shifted to the younger age.

Age Factors↗
PubMed1980

Cell-surface adhesiveness of mouse leukemias.

Cell-surface adhesiveness of forty-one primary mouse leukemias was quantitatively examined by the Latex (polystyrene) particle adherence (LPA) assay. Mean surface adhesiveness of leukemic cell populations was found to be substantially lower than that of normal mouse thymus, lymph node and spleen cell populations. No significant differences were found among mean LPA-positivity of sixteen thymic lymphomas, sixteen reticulum cell sarcomas and six myelogenous leukemias examined; the LPA-positivity of two nonthymic lymphomas and one undifferentiated leukemia was higher and comparable with that of normal mouse thymus cells. Comparison of the LPA-positivity of normal thymus cells and thymic lymphomas indicated that the malignant conversion of thymus cells was either accompanied or followed by a decreased cell-surface adhesiveness.

Animals↗
PubMed1980

Bone sarcomas in 239Pu-treated mice.

Female ICR mice were injected with a monomeric form of 239Pu (180.1 kBq/kg) at the age of 10 weeks and during the long-term contamination the incidence of bone sarcomas was studied. Average survival of 100 control mice was 545 +/- 14 days, the 100 plutonium-given mice survived 420 +/- 10 d and 50 sarcoma-bearing animals 456 +/- 11 days. Most of the 61 induced sarcomas were located in the spine (70%) and in trabecular parts of the other bones. Among these 61 tumors there were 55 osteoblastic osteosarcomas, 4 immature undifferentiated sarcomas and 2 angiosarcomas. In 6 tumor-bearing mice metastases were observed in lungs, liver, intracranial cavity and in mediastinal lymph nodes. Among control mice only one osteogenic mandibular sarcoma was verified. The osteosarcoma incidence was evaluated with respect to the retained activity and cumulative average skeletal dose. The results were discussed and compared with data published by others.

Animals↗
PubMed1980

Terminal hematological changes in mice bearing osteosarcomas induced by plutonium-239.

Terminal hematological changes were studied in female ICR mice injected intravenously with 181.1 kBq/kg of monomeric 239Pu. Cellularity and differential cell counts in femoral bone marrow and spleen, as well as peripheral blood counts were determined. The results were evaluated with respect to the quantitative hematological changes and to the diagnosis of proliferative disorders. As far as the nonstochastic response is concerned, evidently decreased cell counts, without abnormalities in myelogram, were observed in the femoral bone marrow of 239Pu-treated mice and only a mild leukopenia was present in peripheral blood. No significant difference was observed between the hematological response of tumor-bearing mice and the response of mice free of osteosarcomas.

Animals↗
PubMed1979

Effects of 226Ra and X-irradiation on the proliferative and differentiative ability of mouse hemopoietic stem cells.

The ability of hemopoietic stem cells to repopulate spleens of heavily irradiated syngeneic hosts in form of macroscopically visible clonal colonies of differentiating cells was studied in mice exposed for 32 and 4 weeks to internally deposited 226Ra (0.56 and 0.46 muCi per mouse respectively) or to 100 rad X-irradiation. Exocolonizing test and cytological techniques were used for quantitative evaluation. The size of stem cell compartment was reduced and the function of the surviving stem cells was altered by radium and X-ray irradiation. The proliferation and maintenance of hemopoietic cell populations were found to depend not only on the numbers of stem cells but also on their multiplicative and differentiative capability.

Animals↗
PubMed1979

Effect of 239Pu on mouse hemopoietic stem cells in different types of bone marrow cavities.

Repopulative activity of hemopoietic stem cells of mice given i.v. 5 kBq 239Pu/mouse (166.5 kBq/kg) was followed. The activity retained was measured in the whole mouse, the skeleton and the liver. Simultaneously average cumulative skeletal dose was calculated. Quantitative parameters of the stem cell compartment and the marrow cellularity were studied in variously arranged bones (femur, pelvis, lumbar vertebra) using the exocolonizing test and cytological techniques. The effects of radiation were most marked in lumbar vertebra, less serious changes were found in pelvis and only a moderate response was present in femur. The bone marrow hemopoiesis is damaged in various bone sites to different degrees and the percentage of cells at risk appears higher in trabecular than in cortical bone.

Animals↗
PubMed1977

3H-TDR labelling of osteoprogenitor cells after 226RA incorporation in mice.

The time course of 3H-TDR labelling index of osteoprogenitor cells and the doses in endosteum of lumbar vertebra and distal femoral epiphysis were autoradiographically determined in young female mice after single injections of 19.7 and 55.9 micronCi/kg body weight of 226Ra. The selected bone areas were examined in animals killed 2 hours to 28 days after the injection of nuclide. It was ascertained that changes in the relative labelling index are depending on the absorbed doses of alpha radiation. The possible relevance of these experimental findings for the explanation of the osteosarcoma induction and localization is discussed.

Animals↗
PubMed1977

Planimetric evaluation and comparison of roentgenograms of osteogenic sarcomas induced by 226Ra and 224Ra in mice.

Osteosarcomas were induced in mice by three activities of 226Ra (8.8 micronCi, 24.6 micronC and 70.5 micron Ci/kg) and by three activity levels of 224Ra administered in fractionated doses during a period of 75 weeks (total activity per mouse: 0.65 micron Ci, 1.88 micron Ci). In the 226Ra series 74 cases and in the 224Ra series 89 cases of osteosarcomas were evaluated by means of planimetric measurements of roentgenographic images, including the calcified structures. Even though it is not possible to differentiate the series precisely, still some differences between tumors under study could be found. In comparison with 226Ra series, the sarcomas induced by 224Ra are in average rather larger, calcified stuctures appear not to be fully developed and differentiated, he anatomical distribution is different from that characteristic to the 226Ra induced tumors, the mean life span is shorter. It is quite likely that not only the incidence but also some of the features of osteosarcomas are dependent on the time and tissue distribution of the dose delivered.

Animals↗
PubMed1975

Distribution of the femoral colony-forming cells in 226Ra-injected mice.

Distribution of damage caused by the retained 226-Ra to the femoral haemopoiesis has been studied in mice injected with 0.02 and/or 0.09 muCi of 226-Ra/g. The exocolonizing test and the 59-Fe uptake in recipient spleens have been used. Non-uniform radiation effect has been observed in the bone marrow cellularity as well as in the CFU counts within 10 weeks after nuclide injection. The lowest depression appears in the distal femoral ends. The changes are not so serious in the proximal parts and are only moderate in the shafts. The results have been discussed from several standpoints.

Animals↗