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J Pospísil

Publications and source records attributed to J Pospísil.

At least 19 recordsLinked to original sources
PubMed1992

Determination of ethyl biscoumacetate and its metabolite 7-hydroxyethyl biscoumacetate in human serum by high-performance liquid chromatography and mass spectrometry.

An efficient reversed-phase high-performance liquid chromatographic method has been developed for the determination of ethyl biscoumacetate (EBA) and its metabolite in human serum, using the mu Bondapak C18 column and methanol-water-phosphoric acid (56:46.8:0.2, v/v/v) as the mobile phase. This method permitted the determination of both EBA and a metabolite in human serum. The latter has been mentioned by other authors only in urine samples, where significant concentrations were found. Identification of the metabolite as 7-hydroxyethyl biscoumacetate was based on its chromatographic separation, followed by isolation from the eluate and direct mass spectrometric identification. It has been found that the higher EBA concentrations in human serum described by Brodie et al. [J. Pharmacol. Exp. Ther., 106 (1952) 453] were caused by the insufficient resolving power of the spectrophotometric method used, leading to overlapping of the UV spectra of the parent drug and its metabolite.

Chromatography, High Pressure Liquid↗
PubMed1992

Binding parameters of phenytoin during monotherapy and polytherapy.

The present in vivo study elucidated the effect of other commonly comedicated drugs on the phenytoin (PHT) Scatchard binding parameters. Specimens of 150 epileptic patients chronically treated with anticonvulsant drugs were analyzed. The results of covariance analysis suggest that phenobarbitone, ethosuximide, diazepam and folic acid do not alter binding of PHT to serum albumin. The contribution of carbamazepine and medazepam to the free fraction of PHT (decrease of about 0.4%) and/or Scatchard binding capacity (increase of about 1/3) is ambiguous and not statistically significant at the p less than 0.05 level. On the contrary, we found a statistically significant decrease of PHT binding in patients comedicated with valproic acid (VPA) and primidone (PRM). The decrease of about 25% in binding capacity evoked an increase of about 1% (VPA), and 1.5% (PRM), respectively in PHT free fraction.

Adult↗
PubMed1992

[Relation between lipid-bound sialic acid in blood serum and plasma andin human tumors].

Athymic mice with transplanted osteosarcoma and carcinoma of the rectum were found to have increased blood plasma levels of lipid-bound sialic acid (LSA). To verify the applicability of the method of LSA determination, patients with cancer of the mammary gland, rectum, and colon were examined for their LSA level. The serum LSA level was significantly increased in patients with cancer of the mammary gland and rectum, compared to levels determined in the serum of healthy volunteers. The serum LSA level elevation was even more pronounced in patients with carcinoma of the colon. In patients with carcinoma of the colon who were in remission at the time of blood collection the serum LSA level was found to be reduced to control values.

Animals↗
PubMed1991

Sex and season-related differences of basic haematological values in the mountain reedbuck (Reduncula fulvorufula).

1. Basic haematological values in the peripheral blood of four male and 13 female mountain reedbucks (Reduncula fulvorufula) have been repeatedly estimated. 2. Comparing these results for both sexes, we noted pronouncedly lower haematocrit values and haemoglobin contents in females (statistical significance less than or greater than 1%). In the white blood cells only an increased proportion of neutrophils in females was apparent. 3. We have been unable to find seasonal related differences in the red and white blood overall picture of the cells during the summer and winter seasons with the exception of raised red cell counts and increased proportion of monocytes in the winter. The presented findings are compared and discussed with those abstracted from the literature.

Animals↗
PubMed1991

[Changes in platelet aggregation and cAMP levels in isolated blood platelets in rats after 5.0 Gy and 10.0 Gy whole-body irradiation doses].

Rats were subjected to whole-body irradiation with doses of 5.0 Gy and 10.0 Gy. After intervals of 1.5 hours, 3, 6, 12 and 24 hours following irradiation the authors tested the aggregation capacity of thrombocytes after induction with adenosine--5--diphosphate and the cAMP level in isolated thrombocytes. Statistically significant differences between experimental and control groups were found particularly at some time intervals in rats irradiated with 10.0 Gy. The authors found a significant acceleration of the time of maximal aggregation at time intervals of 3.6 and 24 hours following irradiation with 10.0 Gy. Only at the time interval of 3 hours after irradiation with 10 Gy a statistically significant reduction of the maximum aggregation, as compared with the control group, occurred, and similarly the tang alpha value indicates that also the initial rate of aggregation was lower. The cAMP level in isolated thrombocytes was markedly reduced in particular after 5.0 Gy already during the early intervals after irradiation. A temporary increase of the cAMP levels was recorded 3 hours after irradiation with 10.0 Gy which may explain the reduced aggregation capacity of thrombocytes found during the same time interval. The results of both tests are not sufficient evidence of a hypercoagulation state after irradiation with the mentioned doses within 24 hours after irradiation.

Animals↗
PubMed1991

[Binding of phenytoin to serum albumin in vitro and in vivo].

The present paper describes an ultrafiltration method of determination of the concentration of free phenytoin (DPH) in serum and its use for the study of the binding equilibrium phenytoin--albumin. The procedure was employed to determine the binding affinity of serum albumin (a) in a group of healthy volunteers (n = 8) in in vitro conditions, (b) in a group of healthy volunteers (a mixed serum, n = 6) and (c) in a group of patients suffering from epilepsy with fits of the generalized type grand mal (n = 15) in in vivo conditions. The calculation of binding parameters was carried out by the method of nonlinear regression analysis with the use of the one-parameter Scatchard's model of the bond. Binding activity of serum albumin in the volunteers of group (a) was N.Ka = 17,500 l/mol, group (b) N.Ka = 18,700 l/mol, and in patients with epilepsy n.Ka = 19,200 l/mol. The results of covariational analysis demonstrated good agreement in the binding parameters of all three groups under study. The paper also discusses the suitability of the binding model used and the mathematical processing and possible use of the binding parameters measured in in vitro conditions for the estimation of the value of the free fraction of the drug in patients with epilepsy.

Adult↗
PubMed1990

[Comparison of plasmatic and renal clearance of lithium].

The authors elaborated a method for assessment of the renal lithium clearance, CLr, the results of which correlate well with the plasmatic clearance (CLp] (r = 0.785, p less than 0.05). This correlation improved substantially after correction of CLr to the clearance of endogenous creatinine, CLcr (r = 0.945; p less than 0.05). The mean values of CLr of the investigated group--26.4 ml/min are in agreement with the results published by other authors. A significant correlation between CLr and CLcr (r = 0.826, p less than 0.05) along with comparison of the intraindividual variability of assessed results indicates that it is better to use as a parameter of sodium absorption from the proximal tubule the fractional lithium clearance rather than absolute values of CLr.

Adult↗
PubMed1990

[Review: heparin. 1. Methods of determination and inhibitory mechanisms of some coagulation factors].

In a brief survey four groups of determining methods are reported for the purpose of monitoring the heparin therapy, with their advantages and disadvantages being assessed simultaneously. Emphasis is placed on the heterogeneity of heparin with approximately 120 fractions which are the cause of different manners of response and an impediment to the development of a rapid, reliable and economically advantageous method. Finally, all heparin factors in the plasma are enumerated and their mechanisms of action on individual coagulation factors are referred to.

Animals↗
PubMed1990

[Review: heparin. 2. Effect on thrombocytes, vascular walls and fibrinolysis].

In a brief survey the impact on thrombocyte functions and thrombocyte values caused by heparin and its fractions is reported, with the acute and immuno-allergic form of heparin-induced thrombopenia being widely dealt with. Furthermore, the relationship between heparin and vessel wall, particularly then its endothelial layer, is discussed and finally, its impact on the mechanisms of fibrinolysis is reported.

Animals↗
PubMed1990

Influence of cloprostenol-15-glycal on some hematologic values.

Cloprostenol-15-glycal is an analog of natural prostaglandin F2 alpha. It is prepared fully synthetically and is a basic substance of the veterinary medicament of firm name Glystrofan (chem. conc. Spolana, Neratovice, CSR). The effect of this substance was studied after intravenous application in double concentration on the blood cell count in experiment on rats. A significant decrease of erythrocyte count was observed in late sampling intervals especially after higher dose. A temporary elevation of leucocyte count occurred in white blood cell series. There was lymphocyte count elevation, while neutrophil count decreased. In the course of experiment a decrease of thrombocyte count occurred, especially after higher dose. Characteristic of described changes corresponds to that, which was observed by prostaglandins of series E. Changes in perifery blood cell count can be in agreement with the effect of cloprostenol-15-glycal on the production or influence of growth factors and on the proliferation of pluripotent hematogenic cells respectively.

Animals↗
PubMed1990

[The genetic contribution of cows to the prevalence of mastitis in the following generation].

Investigations of mastitis prevalence were performed in 1227 dam-daughter pairs during 1985-1988. From the records of the last 10 years, the findings concerning mammary gland were obtained. Six herds of agricultural co-operatives in the Brno region were investigated. In the early period the Bohemian Pied breed, later the crosses of this breed with Red Holstein and a low genetic proportion of Ayrshire cattle, dominated in the set of cows. Udder health was assessed using the clinical and bacteriological findings in individual udder quarters and the results of the rapid mastitis test NK. Based on this data, the cows were divided into two groups--resistant and susceptible. The lactation order in which the disease appeared for the first time was of great importance. The occurrence of the disease in daughters and udder health in dams were in a significant relation (P less than or equal to 0.01). While nearly 50% of daughters of susceptible dams were affected, it was only 25% in daughters of the resistant group. The assessment of heritability of resistance to mastitis was carried out on the principle of dam-daughter regression. The index of heritability ĥ2 = 0.52 +/- 0.06 was calculated. The results show that the genetic contribution of dams to the susceptibility of daughters to mastitis is significant.

Animals↗
PubMed1990

[Photodynamic therapy of human tumor xenotransplants in athymic nu/nu mice].

The effect of phototherapy on the growth of two human tumors, i.e. carcinoma of the rectum I and III, was studied. The tumors were xenotransplated into athymic nu/nu mice. Meso-tetra-(para-sulfophenyl)-porphin, TPPS4, was used as photosensitizer. Incorporation studies showed the optimal dose for phototherapy to be 10 mg/kg TPPS4 and the time interval 72 hours. Under these experimental conditions (helium-neon laser, 632, 8, 300 J/cm2) one of six tumors was cured in the group with carcinoma of the rectum I, and that both after IV and IT administration of the photosensitizer. The other five experimental animals exhibited only partial responses to phototherapy. In the group with carcinoma of the rectum III, five out of six tumors were cured by IT administration of TPPS4 under the same experimental conditions. In one mouse there was only partial response to phototherapy. After IV administration of TPPS4, however, not a single tumor was cured and the response to phototherapy was only partial in all the six experimental animals.

Animals↗
PubMed1990

An experimental immunoscintigraphic study with anti-CEA monoclonal antibody (DG2).

Monoclonal antibody D11-DG2 (DG2) against carcinoembryonic antigen (CEA) was examined for suitability for radioimmunodetection of human tumors grown in nude mice. Antibodies DG2 and a control antibody of the same IgG1 subclass were labeled with 131I and injected into mice bearing one of three types of CEA-containing tumors (cell lines LS 174T, HT-29 and Rec S) and/or a CEA-negative tumor (Rec R). Gamma-camera imaging and distribution studies revealed that CEA-containing tumors selectively accumulate DG2 but Rec R does not. As the tumors differ in CEA-content, the highest accumulation of 131I-DG2 (corresponding to the best scintigraphic imaging) was found in LS 174T tumors, intermediate in Rec S and lowest in HT-29 tumors. The mean tumor-to-blood ratios on the sixth day after antibody administration were 4.6, 3.2, and 2.1, respectively, in the control experiments the value of this parameter was always lower than 1. The results showed the applicability of DG2 for immunoscintigraphic studies in patients. Furthermore, a positive correlation was found between the uptake of anti-CEA antibody and CEA-content in the tumors.

Animals↗
PubMed1989

[The role of prostanoids in malignant diseases].

Prostanoids are substances which are of great regulatory importance for the organism. Recently not only their active participation in the metabolism of malignant tissue is discussed, but also the possibility of their use in the comprehensive treatment of malignant diseases. At present the effect on a reduction of metastases after prostaglandin I2 administration (= prostacycline) as well as of prostaglandin E2 is tested experimentally as they inhibit the capacity of primary tumours to form metastases. The possibility is also considered of using quantitative estimation of some prostanoids for evaluation of the severity of invasion of the organism by a malignant process.

Humans↗
PubMed1989

Changes of lipid-bound sialic acid in the plasma of mice bearing benzpyrene-induced tumors.

The level of lipid-bound sialic acid (LSA) was followed in inbred C57Bl/6 mice bearing tumors induced by benzpyrene at a dose of 20 mg per kg of body weight. In the plasma of mice with macroscopically ascertained tumors, the level of LSA was increased significantly. The LSA level was also significantly increased in the plasma of suspect mice i.e., in a period when the tumor was not yet macroscopically ascertained, however, when a change was observed in the motion of the hind limb of mice to which benzpyrene was administered.

Animals↗
PubMed1989

[Effectiveness of selected disinfectant and antiseptic preparations on potentially pathogenic micromycetes].

Using the contact test, the author investigated the antifungal efficiency of 13 disinfectants and antiseptic preparations (hydrogen peroxide, Persteril, Jodonal B, Jodisol, Chlordetal, Famosept-Super, Septonex, Ajatin, Cresolum saponatum, ethanol, Desident spray, chlorhexidine, Galli-Valerio solution) against 23 strains of eight genera of microscopic fungi (Absidia, Aspergillus, Candida, Geotrichum, Mucor, Rhizopus, Torulopsis and Trichosporon). The results revealed that filamentous fungi and among them in particular zygomycetes are more resistant against the above preparations than yeasts. The highest antifungal activity was observed in 5% Creolum saponatum and 1% and 2% Famosept Super. On the other hand, 3% H2O2, 5% Jodisol and 0.1% Chlorhexidine were almost ineffective. On investigations of the vitality of spores and fragments of the mycelium of the tested micromycetes the greatest resistance to desiccation was manifested by conidia and hyphae of aspergilli, the smallest one by blastopores of yeasts Candida albicans and Torulopsis glabrata.

Anti-Infective Agents, Local↗