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J Sikora

Publications and source records attributed to J Sikora.

At least 55 records · Page 3Linked to original sources
PubMed1996

DNA ploidy, S-phase, and Ki-67 antigen expression in the evaluation of cell content of pleural effusions.

Cells from pleural effusions (28 malignant and 14 nonmalignant with reactive mesothelial cells) were examined in parallel by means of conventional cytology and multiparametric flow cytometry. The latter included the evaluation of DNA ploidy, the calculation of DNA index (DI), the determination of S phase fraction (SPF), and cell proliferation associated with Ki-67 antigen expression. Propidium iodide was used for the DNA staining, and fluorescein-conjugated monoclonal mouse antibodies were applied to the human Ki-67 antigen staining. The specimens were analyzed by the Becton Dickinson (BD) FACScan apparatus. 10(4) events were collected, and thereafter the obtained data were analyzed by the software Lysis II and CellFit (BD) for DNA and Ki-67 data analysis, respectively. Out of the 28 cases examined, 18 (64%) of the malignant effusions were aneuploid. All of the benign effusions were typically diploid. The average SPF of benign, malignant diploid, and malignant aneuploid cases was 6, 6, and 30 respectively. The comparison between SPF and DI in malignant cases showed a significant correlation (p < 0.001). The average of Ki-67-positive cells that were benign, malignant diploid, and malignant aneuploid were 11, 19, and 35, respectively. There was a significant correlation between Ki-67 expression, SPF (p < 0.05), and the percent of the aneuploid cell population (p = 0.01). The sensitivity of conventional cytology, the determination of DNA ploidy and of Ki-67 expression, was 80, 64, and 92%, respectively; specificity was 100% for cytology and DNA ploidy and 46% for Ki-67 expression. These data show that Ki-67 antigen expression is a potentially useful adjunct to cytometric DNA content analysis, determination of SPF, and conventional cytology in the diagnosis of malignant pleural effusions.

Cell Division↗
PubMed1996

Imipramine distribution among red blood cells, plasma and brain tissue.

The relations between the concentrations of a drug in the blood (plasma, haemoglobin, red blood cells (RBCs), RBC membranes) and in the brain tissue (homogenate, membranes, cytosol) were investigated during chronic administration of imipramine. Radioimmunoassay was employed to measure the antidepressant concentrations. The concentrations were measured and analysed in 40 rats receiving various doses of imipramine. The concentration of total imipramine (imipramine + desipramine) in erythrocyte membranes (ghosts) amounted to 79.4 +/- 4.6% (mean +/- S.E.M., N = 40) of those measured in intact RBCs. Marked accumulation of the drug in the brain tissue, especially in brain cell membranes, was confirmed. The concentrations in brain tissue homogenate was found to be 14.8 times higher than that in RBCs. Values in brain membranes were 10.9 times higher than that in blood element membranes. There is a significant association between the concentrations measured in brain homogenate, the blood plasma and RBC membranes. Blood concentrations can be used to estimate imipramine concentrations in the brain.

Animals↗
PubMed1995

Serotonin in violent patients with schizophrenia.

CSF levels of 5-hydroxyindolacetic acid (5-HIAA), the serotonin metabolite, were assayed in 10 violent and 10 matched nonviolent patients with schizophrenia. Mean group levels of 5-HIAA in cerebrospinal fluid were found to be nearly identical. Possible explanations, including effects of medications, are discussed.

Adult↗
PubMed1995

The effect of nickel compounds on immunophenotype and natural killer cell function of normal human lymphocytes.

In order to elucidate effects of nickel on human lymphocytes in vitro, peripheral blood mononuclear cells from normal donors were initially tested for viability in the presence of increasing concentrations of two selected nickel salts, sparingly-soluble nickel subsulfide (Ni3S2), and promptly-soluble nickel sulfate (NiSO4). After establishing the toxicity profile, the cells were cultured for 24 h with each compound at three nontoxic concentrations, 0.01 mM, 0.02 mM, and 0.04 mM, to determine its effect on lymphocyte immunophenotype and function. Cells were also cultured in the presence of 0.01-0.04 mM magnesium acetate, Mg(CH3COO)2, while still other cell samples were subjected to a mixture of Mg(CH3COO)2 plus either Ni3S2 or NiSO4 at equimolar concentration. Following the culture, the immunophenotype of the cells was determined by indirect immunofluorescence, using monoclonal antibodies to major differentiation antigens of peripheral blood mononuclear cells, and their natural killer activity toward K562 target cells was measured. Both nickel salts were found to exert distinct effects on lymphocyte phenotype. Exposure of cells to Ni3S2 resulted in the decline of CD4 and natural killer cell populations. NiSO4 diminished the abundance of natural killer cells and, to a limited extent, also of CD4 cells. The nickel salts tested suppressed natural cytotoxicity of peripheral blood mononuclear cells, with Ni3S2 acting more strongly than NiSO4. The addition of Mg(CH3COO)2 to a nickel salt during in vitro culture abolished the above inhibitory effects. Nickel and magnesium salts did not affect CD3, CD8, CD20, and CD11a cell populations. The results indicate that nickel salts have deleterious effects on human peripheral blood mononuclear cells in short-term in vitro culture, but the magnitude of these effects varies, depending on the cell subsets.

Cell Survival↗
PubMed1995

Evaluation of the effect of experimental cow endometritis on bactericidal capability of phagocytizing cells isolated from the blood and uterine lumen.

Studies were undertaken to assess the bactericidal activity of phagocytes isolated from blood and the uterine lumen of clinically healthy cows after ovulation, and from cows in which endometritis was induced experimentally. Experiments were carried out on 28 clinically healthy cows of the black and white lowland breed. Animals were aged 5 years and were used between the 2nd and 8th day after spontaneous ovulation. Cows were divided into four groups. Group I comprised animals in which cell-mediated type immune reaction was induced in the left uterine horn by intrauterine challenge with tuberculin. Cows in this group were initially vaccinated with M. bovis via the intrauterine route. In group II, Arthus type immune reaction was induced by challenging immunized animals with C. fetus ssp. veneralis through intrauterine instillation. The non-specific inflammatory process was initiated in the uterus of animals in group III by one instillation of lipopolysaccharide from S. abortus equi. Animals in group IV were set as control and received a phosphate buffered saline instillation into the uterine lumen. The cells from the left uterine horn were washed out 6 h after induction. Neutrophils were isolated from blood samples collected from all animals within the same time. The bacterial activity of cells from the uterine lumen and blood was assessed with the nitro-blue tetrazolium reduction test. Results are presented as increase in optical density resulting from a constant number of phagocytizing cells (delta OD/10(6) cells). Induction of cell-mediated immune reaction or Arthus type immune reaction in the uterus significantly boosts the intracellular capability of uterine cells to kill bacteria through the oxidation system. Experimentally induced non-specific endometritis weakens the bactericidal activity of uterine phagocytes, while peripheral blood phagocytes efficiently kill the engulfed bacteria.

Animals↗
PubMed1995

[Ca(2+)-channel blockers and binding of tricyclic antidepressive agents].

The interactions between Ca(2+)-channel blockers (verapamil and gallopamil) and synaptic plasma membranes (SPM) from bovine brain or human lymphocyte and platelet plasma membranes were studied. Changes in binding parameters of [3H]imipramine, [3H]desmethylimipramine and [3H]gallopamil were determined after addition of unlabelled verapamil or imipramine and after addition of phosphatidylserine (PS) (PS-stimulation). Specific binding of [3H]imipramine to SPM was decreased and [3H]desmethylimipramine binding was increased by 1 microM verapamil. [3H]gallopamil binds specifically to SPM as well as to platelet and lymphocyte membranes. [3H]gallopamil binding to SPM or lymphocyte plasma membranes was PS-stimulated in contrast to platelet plasma membranes without PS effect on binding. Imipramine inhibited both [3H]gallopamil binding and PS-stimulated [3H]gallopamil binding to SPM or lymphocyte plasma membranes. Mutual effects of tricyclic antidepressants and Ca(2+)-channel blockers on their binding sites require relatively high drug concentrations. Mechanism of Ca(2+)-channel blockers action in the treatment of depression may be connected rather with changes in signal transduction through serotonin and catecholamine receptor systems than with direct interaction of drugs with binding sites for tricyclic antidepressants.

Animals↗
PubMed1995

[Role of heparin in neoplastic angiogenesis].

Angiogenesis, the growth of new capillary blood vessels, is a multistep process required for tumor growth and metastasis. The significant correlation between density of microvessels and occurrence of metastasis was shown in cutaneous melanoma, cancers of breast, lung (non-small-cell), and bladder. It has been shown that heparin play a crucial role in angiogenesis. In this review the mechanism of this regulation was summarized, and it was compared to action of specific antagonists of heparin in angiogenesis. It is known that heparin can promote this process, but some fractions may not. Knowing the complex action of heparin in the angiogenesis, the exact role of heparin in tumor growth and metastasis is unknown. Therefore, we suggest that it is needed to confirm if an use of heparin for treating patients with cancer can prolong their survival.

Heparin↗
PubMed1995

In vitro assessment of the influence of different leucocyte count lavaged from normal and inflamed cow uterus on the mouse embryo development.

The aim of this study was to evaluate the effect of different leucocyte count from normal and inflamed uterus in excess of PMNs on the development of mouse embryos during the morula or blastocyst stages in vitro. Results showed that cultivation of blastocysts in the presence of leucocytes washed from the uterus, after mediation of specific or nonspecific endometritis at a concentration of 1 x 10(4), led to significant inhibition of embryo development. No similar observations were made with blastocysts cultivated in the presence of leucocytes obtained from the normal uterus at 2-4 days after spontaneous ovulation.

Animals↗
PubMed1994

Phagocytic activity of polymorphonuclear leukocytes lavaged from the lungs of horses with clinically diagnosed chronic pulmonary disease.

The aim of this study was to compare phagocytic activity of polymorphonuclear cells (PMNs) from the bronchoalveolar lavage of clinically healthy horses and those with severe chronic bronchiolitis. Research was carried out on 28 horses. Chronic inflammation of the lower airways was diagnosed in nine horses. Cells from the respiratory tract were lavaged according to accepted methods. For comparison, PMNs were isolated from peripheral blood of all investigated horses. The phagocytic activity of PMNs was determined in relation to two standard strains of Staphylococcus aureus, Staph, aureus Smith which was phagocytized after previous opsonization, and Staph, aureus 305, phagocytized without opsonization. From the investigations, it is shown that the PMNs present in the terminal airways of horses with severe chronic bronchiolitis are characterized by decreased phagocytic activity in relation to opsonized Staphylococcus aureus Smith and increased activity in relation to non-opsonized Staphylococcus aureus 305, as compared to the PMNs lavaged from the terminal airways of clinically healthy horses. No changes in the phagocytic activity of the peripheral blood PMNs were observed between clinically diseased horses and healthy horses.

Animals↗
PubMed1993

Evaluation of immunophenotype of lymphoid cells isolated from malignant pleural effusions.

Lymphoid cells, isolated from malignant pleural effusions and collected from patients bearing primary lung carcinoma, were examined by means of indirect immunofluorescence and a panel of monoclonal antibodies vs several CD antigens. The percentages of CD4+ T lymphocytes were found to be significantly depressed in malignant effusions as compared to inflammatory ones. In relation to histological type of cancer it was especially evident in squamous cell and anaplastic carcinomas (small and large cell), in comparison to adenocarcinomas. Expression of T cell antigen receptor tau/delta (TCR-1) on T lymphocytes, demonstrated by BB3 MoAb (vs V delta 2), was significantly higher in malignant effusions as compared with non-malignant ones. This was not the case when A13 MoAb (equivalent of TCS 1) was used (vs V delta 1). Percentage values of NK cells, monocyte/granulocyte series activated cells and B lymphocytes did not differ significantly in malignant and non-malignant effusions. It is concluded that these are T lymphocyte subpopulations which are apparently distinct in both effusion groups examined.

Aged↗
PubMed1992

Two-state model of Paramecium bursaria thigmotaxis.

A theoretical framework has been developed for analysis of the interaction between Paramecium bursaria and a glass surface. Adhesion to and detachment from a solid substrate were considered in the model as transitions between alternative states in cell behavior: (a) swimming, and (b) motionless (positive thigmotactic) state. According to the model and experimental data, a change in the fraction of swimming cells is described by a negative exponential course. The proposed model allows positive thigmotaxis, generally referred to in the literature simply as thigmotaxis, to be considered as the rate-constant of transition into the motionless state. This approach permits quantitative determination of thigmotaxis, and reveals its dependence on the phase of culture growth and the type of medium surrounding the cells. In the mineral maintenance solution, paramecia from the stationary phase of growth swim more slowly than those in the logarithmic phase of growth, and show enhanced thigmotaxis. However, a general relationship between thigmotaxis and swimming speed was not established.

Animals↗
PubMed1992

The search for tumor-associated proteins in pleural effusions by means of monoclonal antibodies and a dot blot assay.

Liquid moiety of 61 pleural effusions was tested for tumor-associated proteins (TAP) by means of a dot immunobinding (dot blot) assay (DIA) and a panel of monoclonal antibodies (Moabs). The sensitivity of the assay was checked using a purified, serially diluted carcinoembryonic antigen (CEA) preparation and an anti-CEA monoclonal IgG system. The latter was examined using both DIA and enzyme-linked immunosorbent assay ELISA solid phase assays in simulated conditions that mimicked the protein content of effusions. Finally, the results of DIA were compared to the immunohistochemistry carried out on cell sediments from the same effusions with similar Moabs. It was found that the prevalence of several TAPs, including CEA, epithelial membrane antigen (EMA), vimentin, tenascin, and Thomsen Friedenreich antigen, was significantly higher in the malignant effusions than in the nonmalignant ones. A total, larger than 2, of detected TAPs in a given fluid, was found almost exclusively in malignant effusions (p less than 0.0001). The detection limit of the DIA for a CEA was determined at 5 ng/ml, while for the ELISA it was 1 ng/ml. Several TAPs, especially the CEA, could be detected in parallel tests, carried out on the liquid moiety and the cell sediments of malignant effusions. The evaluation of selected TAPs in pleural effusions by dot blot assay may be of clinical value.

Antibodies, Monoclonal↗
PubMed1991

Radioimmunoassay of dibenzazepines and dibenzcycloheptanodienes in body fluids and tissues.

In an attempt to establish a radioimmunoassay (RIA), imipramine and amitriptyline immunogens were prepared; desmethyl derivatives were converted into hemisuccinates, conjugated with bovine serum albumin and used for rabbit immunization. [3H]Amitriptyline (4.3 TBq/mmol) and [3H]imipramine (2.9 TBq/mmol) were prepared by catalytic dehalogenation or reductive alkylation. Dibenzazepines and dibenzcycloheptanodienes were determined in biological fluids by a direct method without deproteinization (lower detection limit of 0.5 microgram.l-1); using high-yield methods they were extracted from cell membranes. Assay of tricyclic antidepressants in humans showed that these substances disappear from plasma much earlier than from cell membranes. Dissociation of the antidepressants bound to cell membranes is slow and their plasma concentrations are not influenced by standing for 2 h at 4 degrees C. During preparing the membranes for binding studies these substances are not removed, and they may affect the results of the binding studies.

Amitriptyline↗
PubMed1991

Methylated and demethylated tricyclic antidepressants and their binding to cell membranes.

We studied the binding of methylated and demethylated tricyclic antidepressants (TCA) to synaptic plasma brain membranes (SPM) and to lymphocyte, platelet and erythrocyte membranes. In the synaptic plasma membranes, more demethylated than methylated dibenzazepine derivatives were bound and the binding affinity was decreased. By contrast, in lymphocyte and platelet membranes more methylated derivatives were bound. Phosphatidylserine (PS) enhanced significantly the binding of methylated TCA in SPM without changing the dissociation constant (Kd). Lysophosphatidylserine did not affect the binding. PS also caused an increase of 3H-imipramine binding to lymphocyte membranes but the binding to platelet membranes was not affected. PS also enhanced 3H-5-HT uptake into platelets and 3H-noradrenaline uptake into lymphocytes.

Animals↗
PubMed1990

Tumor specificity of monoclonal antibodies to carcinoembryonic antigen. Immunohistochemical analysis.

The tumor specificity of twelve different monoclonal antibodies (Mabs) against carcinoembryonic antigen (CEA) was assessed by immunohistochemistry. The Mabs had previously been classified into three specificity groups (I-III) on the basis of their reactivity with purified CEA-related antigens by ELISA. Mabs belonging to specificity group III (n = 4) did not cross-react with any CEA-related antigen, including normal cross-reactive antigen of 160 kD molecular weight (NCA-160 = meconium antigen). All Mabs, except one, gave positive immunohistochemical staining of 75-100% of individual tissue samples of colorectal carcinomas and gastric adenocarcinomas. However, when tested against different normal adult tissues, the Mabs displayed marked differences in reactivity. Group III Mabs stained normal colon epithelium, but not parenchymal cells in other organs or, with one exception, cells belonging to the granulocyte and/or macrophage series. Group I and II Mabs, in contrast, stained parenchymal cells in normal colon, submandibular salivary gland, placenta, and pancreas (group I Mab only). They also stained infiltrating and circulating granulocytes and/or macrophages. Lack of cross-reactivity with NCA-160 is the single-best criterion for selecting anti-CEA Mabs with a high degree of tumor specificity. To ensure tumor specificity, CEA-positive, NCA-160-negative Mabs should be checked by immunohistochemistry against cryostat sections of colorectal carcinoma, normal pancreas, submandibular salivary gland, spleen, and liver and for reactivity against circulating granulocytes.

Antibodies, Monoclonal↗
PubMed1990

Plasma levels of antidepressants after their withdrawal.

The period of elimination of tricyclic antidepressant amitriptyline was studied both in plasma and erythrocytes and the influence of the preparation of blood element samples on the elimination of residual antidepressant was examined. Also the effect of stress on antidepressant level was studied. Amitriptyline was not found in plasma 14 days after its withdrawal, while at the same time its levels in erythrocytes were still well measurable. Repeated washing of erythrocyte membranes did not eliminate the residual drug completely. Demethylase activity was found to be enhanced by stress. It is suggested that all results of antidepressant binding studies may be influenced by residual drug concentration in tissues. Interindividual variability may be caused by various intensity of stress mechanisms related to depressive disorders.

Adrenal Glands↗
PubMed1989

[ATPase activity, endogenous depression, lithotherapy and electroconvulsive therapy].

The author gives a brief account of the action of ATP-ases in the organism. He describes the effect of different substances on the action of these enzymes, whereby special attention is paid to the action of psychopharmaceutical preparations, incl. lithium salts, on the activity of Na+K(+)-ATP-ase. In the experimental part he investigates the activity of ATP-ases in endogenous depressions in our population, the influence of Li+ and electroconvulsions on these enzymes. The results are consistent with data in the literature. Changes in the ATP-ase activities in the course of treatment imply that these enzymes are not genetic markers of depressions. The different effect of therapeutic preparations on the activity of ATP-ases indicates that influencing ATP-ase activity in relation to depressive conditions cannot be considered causal.

Adult↗