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J Pospísil

Publications and source records attributed to J Pospísil.

At least 55 records · Page 3Linked to original sources
PubMed1987

Postirradiation haemorrhagic syndrome.

One of the relevant symptoms of damage due to irradiation are the manifestations of haemorrhagic diathesis. The extravascular effusion of the blood in the course of the course of the irradiation disease may sometimes also be the cause of death of the irradiated individual, it may complicate the course of the arisen disease and sometimes even make any necessary therapeutical help impossible. The postirradiation disorder of haemocoagulation and haemostasis is a process very complicated both in its origin and in its course. Many experimental studies have been devoted to the study of the mechanism of origin of this disorder, of its course and of the possibilities of its therapy and actually we already have some clinical results. For a wider information and for the utilization of the up-to-date findings in practise, we hold it reasonable to summarize, in a certain time period, the information, though of a restricted problem, in order to facilitate an orientation in the contributions research has made up to now and to enable the selection of the adequate direction of the future experimental studies. This was the reason for the compilation of this monograph in which a summary of the up-to-date experience published in the literature and the results of our many-year standing experimental work is presented in the first opening chapter. In the second chapter, the mechanisms of blood clotting in man and the most often used laboratory animals in experiments, i.e. the dog, rabbit, rat and guinea pig, are compared. By a comparison of the platelet counts, of the time of their survival and the modes of reaction to the inductors of aggregation, some differences have been demonstrated between human thrombocytes and those of laboratory animals, which may be partly conditioned by some species specific composition of the glycoproteins of the platelet membrane. Further on, the difficulties in the determination of the levels of the individual coagulation factors are referred to and their values established in man are compared with those found in the examined laboratory animals in which decreased levels of factor VII and markedly elevated levels of factors V and VIII have been demonstrated. Next, the physiological inhibitors of blood clotting in man are compared with similar substances found in the blood of laboratory animals. Some differences in the structure and in the function of these substances slowing down the blood coagulation are stressed.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1986

Time-dependent influence of some sedating agents on basic haematological values in various artio- and perissodactylids.

Basic haematological values in 32 animals of five species were estimated after administration of sedating agents. In all species under investigation, a time-dependent decrease of erythrocyte counts, haematocrit values and haemoglobin content was noted during the first 30 min after sedation, for the following 30 min the lowered values remained essentially without any change in zebras. Derived parameters, mean corpuscular haemoglobin, mean corpuscular Hb concentration and mean corpuscular volume did not change during the period of observation. Only insignificant changes in leukocyte count and in the proportion of lymphocytes and neutrophiles were registered. The shortest possible time between sedation and blood sampling is recommended to minimalize a distortion especially in the red blood picture.

Animals↗
PubMed1986

The effect of total body irradiation on the occurrence of chemically induced tumors in mice of inbred strains with different activabilities of the AHH system.

On four strains of inbred mice (C57B1/6, C57B1/10, C3H and DBA2), which were chosen according to their genetically conditioned activability of the arylhydrocarbonhydroxylase system (AHH) the effect was checked of repeated whole body exposure to 60Co gamma rays on the occurrence and origination of the formation of tumors induced by methylcholanthrene. Mice of the strains C57B1/6, C57B1/10 and C3H have a high activability of the AHH system, those of the strain DBA2 exert a low activability. The experiment was supposed to check, how much is the damage of the immunological reactivity induced by radiation able to affect carcinogenic effects of methylcholanthrene. The repeated whole body irradiation of mice neither increased the rate of occurrence of tumors nor affected the time of origination of growth of tumors induced with methylcholanthrene. These results indicate that in the formation of tumors induced with methylcholanthrene, there is a prevalent role of genetically conditioned metabolism of the precarcinogen and not of an intervention into immunologic processes in the organism resulting from the whole body irradiation.

Animals↗
PubMed1985

Monoclonal antibodies against human urinary bladder carcinomas: selectivity and utilization for gamma scintigraphy.

Mouse monoclonal antibodies to human urinary bladder carcinoma cells have been examined by indirect membrane immunofluorescence using a panel of 27 human cell lines. Two of the monoclonal antibodies, 7E9 (IgG3) and S2C6 (IgGl), were found to distinguish between urinary bladder carcinoma cells and normal urothelium. The third monoclonal antibody, T24.06.5(IgGl), discriminated among cell lines of urothelial and non-urothelial origin but did not distinguish between urinary bladder carcinoma and normal urothelial cells. None of the of the antibodies was found to be strictly selective, and occasional cross-reactions with unrelated cell types were observed. The monoclonal antibody 7E9, showing the highest degree of selectivity, was further examined by an indirect immunoperoxidase technique on frozen tissue sections from 19 patients. The antibody reacted with all (7/7) bladder carcinomas examined and gave negative results with control normal bladder mucosa (0/8) and unrelated tumor tissue (0/4) sections. The 7E9 antibody was purified by protein A affinity chromatography, labeled with 131I and used for gamma-scintigraphy in nude mice xenografted with human urinary bladder carcinoma T24. The 7E9 antibody was capable of locating the T24 xenografts in nude mice; it localized preferentially in the T24 tissue compared to normal mouse tissues. The T24 xenografts could not be detected by gamma-scintigraphy with 131I-labeled monoclonal antibody against human mammary carcinoma cells and two other control antibodies. Likewise the 131I-labeled 7E9 antibody was not capable of locating human mammary carcinoma xenografts in nude mice.

Animals↗
PubMed1985

Basic haematological values in the African buffalo (Syncerus caffer caffer) and in the red buffalo (Syncerus caffer nanus).

Basic haematological values in 13 African buffaloes (Syncerus caffer caffer), 11 cows and 2 bulls, and in 2 red buffaloes (Syncerus caffer nanus), 1 bull and 1 cow, are reported. In the African buffalo, the erythrocyte count--mean 9.76 X 10(12) 1(-1)--ranged from 6.72 to 12.42 X 10(12) 1(-1), the haematocrit values--mean 0.391--varied from 0.32 to 0.47 and the haemoglobin content--mean 148.17--was in the range from 122.1 to 172.5 g 1(-1). For the red buffalo only individual values are given. In the African buffaloes, the leukocyte counts--mean 7.39 X 10(9) 1(-1)--ranging from 5.1 to 12.4 X 10(9) 1(-1) were slightly increased compared with man. For the red buffalo only individual values are reported. These values are compared with data abstracted from the literature for related buffalo species. The age-dependent decrease of erythrocyte counts and the age-dependent rise of the eosinophile proportion in the differential count are discussed.

Aging↗
PubMed1985

[Hemostatic mechanisms and malignant tumors].

The mutual relationships between malignant tumours and mechanisms of blood coagulation are presented in a brief survey. In this connection, the mechanisms of a tumour cell entering the circulation through the vessel well and its leaving into the tissues are discussed, the theory of microtrauma being used for explaining these processes. Subsequently, the alterations to be found in the count and function of thrombocytes after contact with a malignant cell and the impact on this cell by blood platelets are represented. As a third factor the activation of blood coagulation which is exercised by substances with a procoagulatory effect produced by the malignant tissue and the frequently observed thrombosis in the course of neoplastic diseases are dealt with in connection with blood level changes of some coagulation factors. In a fourth section the significance of fibrinolysis, its activation and inhibition as well as the production of fibrinolytic activators by neoplasms are discussed.

Animals↗
PubMed1985

Tumour localization of radiolabelled monoclonal antibody in mice bearing human urinary bladder (T24) carcinoma xenografts.

Selectivity of mouse monoclonal antibody 7E9 (IGG3) directed against human urinary bladder carcinoma cells has been examined by indirect membrane immunofluorescence, using a panel of 31 human cell lines. The 7E9 monoclonal antibody discriminated between urinary bladder carcinoma cells and normal urothelium or cells of non-urothelial origin, although occasional reactions with bladder carcinoma-unrelated cell types were observed. The 7E9 antibody was purified by protein A affinity chromatography, labeled with 131I and used for gamma scintigraphy in nude mice xenografted with human urinary bladder carcinoma T24. The 7E9 antibody was capable of locating the T24 xenografts in nude mice; it localized preferentially in the T24 tissue compared to normal mouse tissues. The T24 xenografts could not be detected by gamma scintigraphy with 131I-labelled monoclonal antibody against human mammary carcinoma cells and two other control antibodies. Likewise, the 131I-labelled 7E9 antibody was not capable of locating human mammary carcinoma xenografts in nude mice.

Animals↗