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J Krejsek

Publications and source records attributed to J Krejsek.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Cytoimunofluorometry and its use in the detection of blood platelet activation].

Blood platelet activation is a complex process involved in the physiological hemostasis and also in a number of disorders. Platelets change their morphology, modify their surfaces glycoprotein receptors with adhesive functions. Procoagulant microparticles are shedding and the aggregates of platelets with leucocytes are appearing. The activated platelet can be detected by flow cytometry after imunofluorescent staining.

Flow Cytometry↗
PubMed2000

[Resistance to cytostatics in hematologic neoplasm cells. Part III].

Resistance to cytotoxic drugs is a serious drawback in the treatment of patient with tumours, both of the haemopoietic and non-haemopoietic origin. The cytotoxic effect of drugs on the malignant cells manifests as the process of apoptosis. In the resistant malignant cells, apoptosis becomes prevented by several mechanisms. The multidrug resistance (MDR) is one of the principal mechanisms when the cancer cells develop resistance to multiple chemically and functionally unrelated cytotoxic compounds. The decrease of the cytotoxic drug concentration at the molecular target site may come from activation of some efflux membrane systems participating in the transport of cytotoxic drugs out of the cell (e.g. Pgp, MDR, and LRP). Another mechanism of resistance is the increased enzymatic detoxification of the drug by glutathion-S-transferase system. Changes in the molecular target of the cytotoxic drug such as topoisomerase molecule can be also responsible for the resistance. At least two additional mechanisms of resistance of tumour cells were identified. Resistance can come from either deregulation of proapoptotic mechanisms in tumour cells or by increased activity of reparation processes which control the damaged molecule of DNA. Several methods that detect the cause of resistance in distinct cell populations have been developed. The great effort is now focused on both the detection of mechanisms of the resistance and on the clinical procedures of overcoming the resistance to cytotoxic drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

[Resistance of hematologic neoplasm cells to cytostatics. Part II].

Resistance to cytotoxic drugs is a serious drawback in the treatment of patients with tumours, both of the haemopoietic and non-haemopoietic origin. The cytotoxic effect of drugs on the malignant cells manifests as the process of apoptosis. In the resistant malignant cells, apoptosis becomes prevented by several mechanisms. The multidrug resistance (MDR) is one of the principal mechanisms when the cancer cells develop resistance to multiple chemically and functionally unrelated cytotoxic compounds. The decrease of the cytotoxic drug concentration at the molecular target site may come from activation of some efflux membrane systems participating in the transport of cytotoxic drugs out of the cell (e.g. Pgp, MDR, and LRP). Another mechanism of resistance is the increased enzymatic detoxification of the drug by glutathion-s-transferase system. Changes in the molecular target of the cytotoxic drug such as topoisomerase molecule can be also responsible for the resistance. At least two additional mechanisms of resistance of tumour cells were identified. Resistance can come from either deregulation of proapoptotic mechanisms in tumour cells or by increased activity of reparation processes which control the damaged molecule of DNA. Several methods that detect the cause of resistance in distinct cell populations have been developed. The great effort is now focused on both the detection of mechanisms of the resistance and on the clinical procedures of overcoming the resistance to cytotoxic drugs.

Antineoplastic Agents↗
PubMed2000

[Resistance of cells in hematopoietic malignancies to cytostatic agents. Part 1].

Resistance to cytotoxic drugs is a serious drawback in the treatment of patients with tumours, both of the haemopoietic and non-haemopoietic origin. The cytotoxic effect of drugs on the malignant cells manifests as the process of apoptosis. In the resistant malignant cells, apoptosis becomes prevented by several mechanisms. The multidrug resistance (MDR) is one of the principal mechanisms when the cancer cells develop resistance to multiple chemically and functionally unrelated cytotoxic compounds. The decrease of the cytotoxic drug concentration at the molecular target site may come from activation of some efflux membrane systems participating in the transport of cytotoxic drugs out of the cell (e.g. Pgp, MDR, and LRP). Another mechanism of resistance is the increased enzymatic detoxification of the drug by glutathion-S-transferase system. Changes in the molecular target of the cytotoxic drug such as topoisomerase molecule can be also responsible for the resistance. At least two additional mechanisms of resistance of tumour cells were identified. Resistance can come from either deregulation of proapoptic mechanisms in tumour cells or by increased activity of reparation processes which control the damaged molecule of DNA. Several methods that detect the cause of resistance in distinct cell populations have been developed. The great effort is now focused on both the detection of mechanisms of the resistance and on the clinical procedures of overcoming the resistance to cytotoxic drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

[CD4 lymphopenia and postoperative immunosuppression in cardiac surgery].

The diversity and heterogeneity of biologic reactions is a condition sine qua non for the adaptation of live organisms to changes of external environment. Reactions of the immune system enable survival even in extreme conditions. Modern medicine often reaches situations never met by the organism in phylogenesis. Thanks to up-to-date therapeutical approaches many patients survive with grave symptoms such as multiple organ failure and extensive forms of injury. New infectious diseases are emerging, e.g. HIV/AIDS. Notwithstanding the broad array of external insults, it becomes obvious that organisms mobilize defence reactions according to a general scheme. Likewise, exhaustion of the immune potential occurs according to an archetypal pattern. In the case of cell-mediated immunity the faultless course of which is of critical importance for organisms in extreme conditions, the loss begins with the absence of reactivity of T-cells to specific antigens to end with the absence of their reactivity to polyclonal mitogens. The article deals with pathogenic mechanisms underlying the onset of immunodeficiencies caused by both infectious and non-infectious stimuli with special regard being focused on cardiac surgery in extracorporeal circuit.

CD4-Positive T-Lymphocytes↗
PubMed2000

[Determination of intracellular molecules in cells in hematopoietic malignancy using flow cytometry].

BACKGROUND: Detection of membrane molecules by immunophenotypisation is a routine counterpart of the laboratory tests which are needed for the complex diagnostic procedures of hematopoetic malignancies at present. The immunochemical detection of intracellular molecules is essential in such cases, where the expression of surface molecules on malignant cells is poor, or where the results of other diagnostic analyses are unequivocal (cases with ectopic expression of other lineage-specific molecules and cases of biphenotypic leukemias). METHODS AND RESULTS: We followed the procedure using 4% solution of paraformaldehyd in phosphate buffered saline for fixation of cells. Lysing solution G (Becton-Dickinson) was used for permeabilisation of cells to detect nuclear and cytoplasmatic molecules. The permeabilised cell suspension was than washed with 0.5% solution of Tween 20 in phosphate buffered saline. This simple and rapid procedure is readily available for the routine detection of intracellular molecules. This approach is important for the diagnosis of hematopoetic malignancies.

Antigens, CD↗
PubMed2000

Serum soluble adhesion molecules (sICAM-1, sVCAM-1 and sE-selectin) in healthy school aged children and adults.

The aim of this study was to map normal levels of serum soluble isoforms of adhesion molecules in relation to age and sex in the group of school-aged children. sICAM-1, sVCAM-1 and sE-selectin were determined in the group of 158 normal children subdivided into two subgroups; 6-10 years (68 children, median age 8 years) and 11-15 years (90 children, median age 12 years) and in 70 normal adult blood donors (25 females and 45 males, median age 46 years). The levels of sICAM-1 and sE-selectin fell down significantly over the age range 6-15 years, while the level of sVCAM-1 was remained. Age-related normal ranges were established using correlation analysis and were expressed as the 5%-95% percentiles intervals: sICAM-1 206.8-486.8 ng/ml, sE-selectin 36.7-153.2 ng/ml in the group of 6-10 years old children, sICAM-1 184.1-354.0 ng/ml, sE-selectin 29.9-114.1 ng/ml in group of 11-15 years old children. The levels of sVCAM-1 were 359.6-822.0 ng/ml and were constant within the examined age interval from 6 to 15 years. The influence of sex was also assayed and it was not statistically significant in any age category tested. Normal ranges of sICAM-1 (60.2-218.4 ng/ml), sE-selectin (8.3-116.9 ng/ml) and sVCAM-1 (338.0-1148.0 ng/ml) were established for adult population of healthy blood donors using the same methods.

Adolescent↗
PubMed1999

Cytokines and adhesion molecules in the course of acute myocardial infarction.

The plasma levels of interleukin 1 beta (IL 1beta), interleukin 6 (IL 6), interleukin 8 (IL 8), tumor necrosis factor alpha (TNF-alpha), E-selectin, ICAM 1 and C-reactive protein (CRP) have been studied in 24 patients with acute myocardial infarction in the course of 96 h. The plasma IL 1beta and IL 6 levels were continually elevated during the 96 h study period (the peak of plasma IL 1beta level was 22.2 pg/ml, S.D. 8.6, P < 0.001, normal values of IL 1beta are less than 10 pg/ml, the mean peak plasma concentration of IL 6 was 184.9 pg/ml, S.D. 134.7, vs. normal values of 15.57 pg/ml, S.D. 2.4, P < 0.001). The mean plasma IL 8 level was increased for the duration of the study, the mean plasma IL 8 level was 103.0 pg/ml, S.D. 23.4 (normal value was below 30 pg/l, S.D. 8.0) P < 0.001. The plasma TNF-alpha level was elevated throughout the time of observation without any significant peak. The mean plasma TNF-alpha concentration was 46.8 pg/ml, S.D. 2.13, vs. normal value 4.35 pg/ml, S.D. 1.23, P < 0.001. The plasma E-selectin level reached the mean level of 145.1 ng/ml, S.D. 75.4, vs. normal value 29.1-63.4 ng/ml, P < 0.001 at an interval of 15-42 h after the onset of the symptoms. The plasma ICAM 1 level showed only a slight significant increase during the first 36 h. The plasma CRP concentration increased later than IL 6, and reached a peak at 42 h after the onset of the symptoms (69.2 mg/l, S.D. 29.9, vs. 1.2 mg/l, S.D. 4.7, P < 0.0001). We conclude that cytokines and adhesion molecules can play an important role in the mechanisms of tissue injury in the process of ischemia and reperfusion.

Adult↗
PubMed1999

Serum soluble adhesion molecules (sICAM-1, sVCAM-1, sE-selectin) and neopterin in patients with Sjögren's syndrome.

Sjögren's syndrome is a systemic autoimmune disease characterized by focal lymphocytic infiltration of the salivary and lacrimal glands. Expression and up-regulation of adhesion molecules and activation of cellular immune system is essential for the migration of inflammatory cells into tissues. Soluble forms of adhesion molecules sICAM-1, sVCAM-1, sE-selectin and neopterin were analyzed in serum of 17 patients with primary Sjögren's syndrome and 11 patients with secondary Sjögren's syndrome together with 26 age-matched healthy blood donors. There were significantly higher serum concentrations (mean +/- 1SD) of sICAM-1 (362.0 +/- 67.9 ng/ml, p < 0.001), sE-selectin (78.7 +/- 28.1 ng/ml, p < 0.001) and neopterin (17.9 +/- 6.4 nmol/l, p < 0.001) in primary Sjögren's syndrome patients in comparison to control group (sICAM-1: 128.3 +/- 46.9 ng/ml, sE-selectin: 46.3 +/- 39.5 ng/ml, and neopterin: 7.6 +/- 2.3 nmol/l). Sera from patients with secondary Sjögren's disease contained significantly higher levels of sICAM-1 (356.0 +/- 62.4 ng/ml, p < 0.001), sE-selectin (65.5 +/- 27.0 ng/ml, p < 0.05), and neopterin (18.8 +/- 9.8 nmol/l, p < 0.001) in comparison with control group. There were no significant differences between patients with primary and secondary Sjögren's syndrome in any parameters tested. No statistically significant differences in serum levels of sVCAM-1 were found either in patients with primary or secondary SS compared to control group.

Adult↗
PubMed1999

[Detection of multiple myeloma cells using multicolor immunofluorescence and flow cytometry].

The advent of new therapeutic approaches to multiple myeloma made necessary the introduction of novel methods for detection of minimal residual disease. Among others approaches residual disease can be detected by the immunofluorescence using flow cytometry. We have examined the co-expression of CD19, CD38, CD45, CD54, CD56, and CD138 molecules in cells of peripheral blood and bone marrow aspirates in patients with multiple myeloma by 3-color flow cytometry. For the detection and characterization of multiple myeloma cells, combinations of following antibodies were used: anti-CD19 FITC, anti-CD38 FITC, anti-CD38 PE, anti-CD54 FITC, anti-CD56 PE-Cy5, anti-CD45 PE, anti-CD45 PE-Cy5 (Immunotech) and anti CD138 PE (Serotec). The samples were analyzed using EPICS XL (Coulter) flow cytometer, and the analysis was based on at least 10,000 events. Samples from 17 patients were analyzed. The percentage of multiple myeloma cells ranged between 0.3% and 54.2% in bone marrow aspirates and between 0.0 and 11.8% in periferal blood. The expression of CD138, CD38, CD54 and CD56 molecules was found in 100%, 100%, 85% and 68% of examined cases, respectively. In our opinion, multiple myeloma cells are best characterized by following combinations of antibodies: CD38 FITC/CD138 PE/CD45 PE-Cy5, CD54 FITC/CD138 PE/CD56 PE-Cy5 or CD54 FITC/CD38 PE/CD 56 PE-Cy5. The identification of a malignant clone is the first and the most important step in the characterization of the disease, determination of its prognosis and the detection of residual disease after treatment. Three-color flow cytometry represents a method which can meet these goals.

Antigens, CD↗
PubMed1998

[Helicobacter pylori CagA antigen antibodies].

BACKGROUND: CagA antigen of Helicobacter pylori is highly immunogenic in humans. There is an increasing evidence that infection with CagA-positive strains is related to the development of peptic ulcer disease, atrophic gastritis, or gastric cancer. The aim of our study was to assess seropositivity to CagA in a group of 95 clinically symptomatic adults who underwent gastroduodenoscopy and to correlate results to their disease characteristics. METHODS AND RESULTS: Serum immunoglobulin G antibodies to CagA detected by ELISA kit (Helicobacter p120, Viva Diagnostika, Germany) were compared to standard IgG specific antibodies against a pool of H. pylori antigens Synelisa Pin plate, ELIAS, Germany). Immunoglobulin G antibodies to CagA were present in 5/31 (16%) serum samples from H. pylori negative persons and 10/28 (36%) serum samples from H. pylori positive patients without peptic ulcer disease compared with 8/11 (73%) H. pylori positive patients with peptic ulcer disease in the past, 11/13 (85%) H. pylori positive patients with duodenal ulcers or duodenitis and 4/5 (80%) H. pylori positive (1/7, 14% H. pylori negative) serum samples from patients with gastric resection for peptic ulcers in the past. Serum levels of antibodies to CagA in the groups of patients with peptic ulcer disease in the past, with present duodenal ulcers of duodenitis and in H. pylori infected patients with gastric resection were significantly higher then those of H. pylori infected patients without peptic ulcer disease (P < 0.05). On the other hand, there was no significant difference in the presence of the specific antibodies against at pool of H. pylori antigens between these four groups. CONCLUSIONS: These data suggest that serologic response to the CagA antigen is more prevalent in H. pylori positive persons with present or past peptic ulceration than among infected persons without peptic ulcer disease. The presence of antibodies to CagA in H. pylori positive persons may be useful for the identification of patients with higher risk or more severe disease.

Adolescent↗
PubMed1998

Decreased peripheral blood gamma delta T cells in patients with bronchial asthma.

Many cell populations are thought to be involved in the etiopathogenesis of bronchial asthma. We examined by flow cytometry the relative and absolute number of CD3+, CD4+, CD8+, alpha beta TcR+ or gamma delta TcR+ T cells, CD19+ B cells; and CD56+ natural killer (NK) cells in the peripheral blood of 26 adult patients with difficult-to-control asthma (DCA) and 22 patients with minimally symptomatic asthma (MSA). Statistically higher relative and absolute numbers of NK cells (18.39 +/- 10.67% and 0.38 +/- 0.17 x 10(9)/l) in comparison with healthy controls (11.77 +/- 8.06% and 0.25 +/- 0.19 x 10(9)/l) and significantly decreased relative and absolute numbers of gamma delta T cells (3.02 +/- 2.16% and 0.06 +/- 0.04 x 10(9)/l) in comparison with controls (5.65 +/- 2.90% and 0.13 +/- 0.08 x 10(9)/l) in the DCA patient group were found. After pooling of data from both MSA and DCA patients and dividing the patients according to the presence of allergy, the relative and absolute numbers of gamma delta T cells were found to be diminished in both the allergy (3.77 +/- 2.98 and 0.07 +/- 0.05 x 10(9)/l) and nonallergy (3.06 +/- 1.78% and 0.06 +/- 0.03 x 10(9)/l) groups in comparison with healthy controls. The reason for the low number of gamma delta T cells in the peripheral blood of patients suffering from bronchial asthma is under investigation.

Adult↗
PubMed1998

[Endothelial cells and leukocytes--significance of adhesion interactions].

Interactions between endothelial cells, adherence of endothelial cells to the molecules of extracellular matrix, adhesion of leukocytes and platelets to the activated endothelial cell lining are mediated by adhesion molecules belonging into four families: immunoglobulins, integrins, selectins, and cadherins. Adhesion interactions mediate intercellular signaling. Soluble forms of adhesion molecules modulate adhesion interactions. The determination of soluble adhesion molecules in blood is used for indirect evaluation of function or dysfunction of endothelial cells. It is possible to modulate abnormal function of endothelial cells using monoclonal antibodies against adhesion molecules.

Cell Adhesion↗
PubMed1997

[Blood platelet adhesion molecules].

Homeostasis is mediated through interactions of adhesion molecules on the surface of platelets which belong into the families of selectins, integrins and immunoglobulins with soluble plasma proteins, surface molecules of activated endothelial cells and molecules of extracellular matrix. The membrane expression of some adhesion molecules (P-selectin) which are the part of granular system of resting platelet identify activated platelet. Adhesion molecules of platelets could be detected by immunochemistry through flow cytometry. By this approach the inherited defects of adhesion molecules on platelets and the activated platelet could be detected. The detection of activated platelets is very useful in many clinical conditions.

Blood Platelets↗
PubMed1997

[Cell-mediated immunity in patients with Sjogren's syndrome].

BACKGROUND: Sjögren's syndrome (SS) is considered an autoimmune immunopathological disease, which is characterized by disorders of humoral and cell-mediated immunity. The objective of the work was to assess the ratio of T and B lymphocytes, subpopulations of T lymphocytes and NK cells in the peripheral blood of patients suffering from SS. METHODS AND RESULTS: The investigated group was formed by 22 patients with the diagnosis of primary SS (mean age 55.7 years, range 39-83 years), 17 patients with the diagnosis of secondary SS (mean age 60.5 years, range 45-79 years). The ration of CD3-, CD4-, CD8-, CD19-, CD5-, CD25- HLA DR- cells in full blood was assessed by the monoclonal antibody technique of direct immunofluorescence, using evaluation by means of a flow cytometer. The results were compared by statistical methods with a control group of blood donors using Student's t-test, A relative increase of the ratio of CD3- T lymphocytes was revealed in patients with primary SS (75.3 +/- 17.9 %, p = 0.380) and secondary SS (73.7 +/- 11.8, p = 0.326), as compared with controls (65.3 +/- 10.3%). The absolute number of the subpopulation of suppressor helper inducer CD4+ T lymphocytes was markedly lower in patients with primary SS (0.056 +/- 0.27 - 10(9)/l, p = 0.0154), as compared with controls (0.81 +/- 0.27, 10(9)/l. The relative number of suppressor cytotoxic CD8- T lymphocytes was significantly higher in patients with primary SS (33.7 +/- 15.0%, p = 0.0001 and secondary SS (30.5 +/- 11.0%, p = 0.0002), as compared with controls (17.2 +/- 6.0%). The absolute number of inhibitory cytotoxic T lymphocytes was significantly higher in patients with primary SS (0.47 +/- 0.3. 10(9)/1, p = 0.0084) and patients with secondary SS (0.48 +/- 0.3, 10(9)/l, p = 0.0072). The relative number of CD57+ NK cells was significantly higher in patients with primary SS (21.1 +/- 11.0%, p = 0.0001) and secondary SS (19.3 +/- 11.7%, p = 0.0023). The absolute number of NK cells was significantly higher in patients with primary SS (0.28 +/- 0.20, 10(9)/l, p = 0.0025 and in patients with secondary SS (0.31 +/- 0.23, 10(9)/l, p = 0.01). CONCLUSIONS: The revealed statistically significant increases in the number of T lymphocytes in patients with Sjögren's syndrome is probably caused by a significant increase of the subpopulation of CD8+ suppressor cytotoxic T lymphocytes. The latter probably overlap with the population of NK cells. These immunological abnormalities are even more marked in patients with primary Sjögren's syndrome due to the decrease of the absolute number of CD4+ helper inducer T lymphocytes.

Adult↗
PubMed1997

Elevation of serum soluble intercellular adhesion molecule-1 (sICAM-1) and beta-2-microglobulin in Sjögren's syndrome.

Sjögren's syndrome is a chronic inflammatory disease which is believed to be immunologically mediated. It is marked by inflammation and destruction of the salivary glands and lacrimal glands. We have found significantly higher serum levels of sICAM-1 and beta-2-microglobulin in both primary Sjögren's syndrome patients (429.1 +/- 114.33 ng/ml, 4.4 +/- 1.5 ug/ml resp.) and secondary Sjögren's syndrome patients (424 +/- 140.73 ng/ml, 4.4 +/- 2.67 ug/ml resp.) in comparison with healthy controls (189.1 +/- 42.34 ng/ml, 1.3 +/- 0.38 ug/ml resp.). The serum level of beta-2-microglobulin was significantly correlated with the serum level of sICAM-1 in secondary Sjögren's syndrome patients' group.

Adult↗
PubMed1997

[Infection with Helicobacter pylori and its serologic detection].

Pathogenicity of Helicobacter pylori is based partially on the production of toxic substances. On the other hand the gastric mucosal injury may be caused by the Helicobacter pylori-induced host inflammatory response. Considerable antibody response during Helicobacter pylori infection provides a ground for indirect non-invasive serological detection. Appropriate clinical applications of serological tests are based on a good understanding of the antibody response characteristics during Helicobacter pylori infection.

Antibodies, Bacterial↗