Biomedical subjects

M Król

Publications and source records attributed to M Król.

At least 19 recordsLinked to original sources

PubMed2004

Intramolecular signaling in immunoglobulins -- new evidence emerging from the use of supramolecular protein ligands.

The postulated intramolecular signaling in immunoglobulins generated by antigen binding has been controversial for years. The high heterogeneity of immune complexes as signaling systems and the requirement of the immobilized antigen form for efficient triggering of effector activity is likely the reason for the lack of clarity. Here we present new evidence supporting the notion of intramolecular signaling, based on the use of supramolecular dyes that bind to signal-derived specific sites in immunoglobulins.

Antigen-Antibody Complex↗

PubMed2003

Evaluation of relative anti-myeloma activity of high-dose melphalan followed by the first peripheral blood stem cell transplantation, as compared with the second transplantation, and to VAD chemotherapy.

Current treatment in multiple myeloma consists of three courses of chemotherapy in low doses with subsequent hematopoietic stem cell mobilization to the peripheral blood using high-dose cyclophosphamide, collection and conditioning with high-dose chemotherapy (melphalan) followed by retransplantation of autologous peripheral blood stem cells (PBSCT). Only a few studies compare the effects of different phases of therapy on parameters, such as monoclonal immunoglobulin level and the presence of malignant CD38(+) and CD56(+) cells in blood and marrow. The aim of this study was to compare the effects of these two major phases of treatment (conventional and high dose) in the same patients, and furthermore, to compare the effects of the second course of high-dose therapy followed by PBSCT with the effects of the first one. Fifteen patients were included in the study. On average, conventional chemotherapy only slightly reduced the values of all disease markers. In contrast, high-dose therapy resulted in a dramatic effect, rapidly normalizing the values of all parameters. The effects of second PBSCT were only modest compared to the first. These data suggest that high-dose therapy is an efficient method to reduce tumor load in multiple myeloma. Conventional-dose chemotherapy may be simply a waste of time for some patients and may be either omitted or administered after high-dose therapy to consolidate remission.

ADP-ribosyl Cyclase↗

PubMed2002

Egg yolk platelet proteins from Xenopus laevis are amyloidogenic.

The association of amphibian (Xenopus laevis) egg yolk platelet proteins, represented predominantly by lipovitellin, was studied as a model of the formation of amyloid deposits. Two kinds of molecular organization formed by this protein material - native and heat-denatured - were found to exhibit amyloid properties although they differ significantly in structural organization. The first consisted in protein molecules arranged in the natural, physiological, net-like platelet organization, with a tendency to orient uni-directionally. The second was obtained by the gradual removal of Congo red from lipovitellin denatured by heating in an excess of dye. This procedure produced the twisted fibrillar organization of molecules typical for amyloids, represented predominantly by end-to-end associated major polypeptide chains of lipovitellin. Both native and denatured structural forms bind Congo red and produce a green birefringence effect, confirming the near parallel alignment of the complexed Congo red molecules. However, a dye(1,4-bis(1-amino-4-sulfonaphtyl-2-azo)phenylene) closely related to Congo red but with a very weak self-assembling tendency appeared inactive when the spectral shift was studied in a cross-polarization system, indicating in this way that dye supramolecularity is an extra factor which may determine binding to amyloid proteins and specific spectral effects.

Amyloid↗

PubMed2001

Exhalation of H2O2 and thiobarbituric acid reactive substances (TBARs) by healthy subjects.

Enhanced exhalation of H2O2 and TBARs have been reported in various inflammatory lung diseases. This may reflect activated phagocytes influx and free radical generation in the airways. However, to apply these compounds as markers of oxidative stress it is necessary to understand factors influencing their exhalation in healthy subjects. We investigated the concentration of H2O2 and TBARs in expired breath condensate (EBC) of 58 healthy volunteers. EBC was collected seven times every 4 h during 24 h and three times every 7 d during 2 consecutive weeks. The H2O2 exhalation revealed diurnal variation with two-peak values 0.45 +/- 0.29 microM and 0.43 +/- 0.22 microM at 12:00 and 24:00 h. The lowest concentrations, 0.26 +/- 0.13 microM and 0.25 +/- 0.26 microM, were found at 20:00 and 8:00 h. Cigarette smokers exhaled about 2.4 times more H(2)O(2) than never smoked subjects. Moreover, in contrast to nonsmokers, cigarette smokers' H2O2 exhalation was stable over 2 week observation. The mean H2O2 concentration estimated over the whole 2 week period was higher in subjects above 40 years regardless of smoking habit, and it positively correlated with age in never smoked subjects (p <.004). Smoking of one cigarette caused 1.8-fold rise in H2O2 exhalation (p <.01). The baseline H2O2 levels correlated with cumulative cigarette consumption (p <.05) and MEF 25% of predicted (p <.05). Neither moderate exercise nor one puff of salbutamol nor ipratropium influenced significantly the concentration of H2O2 and TBARs in EBC. Only 4 of 120 EBC specimens from never smoked subjects revealed detectable levels of TBARs. Cigarette smokers exhaled more TBARs (p <.05) than never smoked volunteers. Our results indicate that healthy never smoked subjects exhale H2O2 with diurnal variation and significant changes over 2 week observation. Cigarette smoking enhanced H2O2 generation in the airways. These results could be useful for planning studies with exhaled H2O2 as a marker of airway inflammation. Occasional detection of TBARs in EBC of never smoked persons may be a result of sufficient antioxidant activity in the airways that protects tissues from peroxidative damage.

Adult↗

PubMed2001

Heat-induced formation of a specific binding site for self-assembled Congo Red in the V domain of immunoglobulin L chain lambda.

Moderate heating (40-50 degrees C) of immunoglobulins makes them accessible for binding with Congo Red and some related highly associated dyes. The binding is specific and involves supramolecular dye ligands presenting ribbon-like micellar bodies. The L chain lambda dimer, which upon heating disclosed the same binding requirement with respect to supramolecular dye ligands, was used in this work to identify the site of their attachment. Two clearly defined dye-protein (L lambda chain) complexes arise upon heating, here called complex I and complex II. The first is formed at low temperatures (up to 40-45 degrees C) and hence by a still native protein, while the formation of the second one is associated with domain melting above 55 degrees C. They contain 4 and 8 dye molecules bound per L chain monomer, respectively. Complex I also forms efficiently at high dye concentration even at ambient temperature. Complex I and its formation was the object of the present studies. Three structural events that could make the protein accessible to penetration by the large dye ligand were considered to occur in L chains upon heating: local polypeptide chain destabilization, VL-VL domain incoherence, and protein melting. Of these three possibilities, local low-energy structural alteration was found to correlate best with the formation of complex I. It was identified as decreased packing stability of the N-terminal polypeptide chain fragment, which as a result made the V domain accessible for dye penetration. The 19-amino acid N-terminal fragment becomes susceptible to proteolytic cleavage after being replaced by the dye at its packing locus. Its splitting from the dye-protein complex was proved by amino acid sequence analysis. The emptied packing locus, which becomes the site that holds the dye, is bordered by strands of amino acids numbered 74-80 and 105-110, as shown by model analysis. The character of the temperature-induced local polypeptide chain destabilization and its possible role in intramolecular antibody signaling is discussed.

Amino Acid Sequence↗

PubMed2001

[Serum thrombopoietin and interleukin-6 concentration in diagnosis of thrombocytopenia].

Serum concentration of thrombopoietin (Tpo) and interleukin 6 (IL-6) were measured in 37 patients with thrombocythaemia and in the healthy volunteers. 27 patient were classified as persons with chronic myeloproliferative disorder (MPD) and 10 as with reactive thrombocythaemia (RT). The mean plasma Tpo concentration did not differ statistically between the groups. IL-6 levels were significantly higher in patients with RT than in patients with MPD and controls. The mean plasma IL-6 levels was lowest in patients with essential thrombocythaemia. In conclusion, serum IL-6 concentration may be useful in the differential diagnosis of thrombocytosis.

Adolescent↗

PubMed2001

Evidence that supramolecular Congo red is the sole ligation form of this dye for L chain lambda derived amyloid proteins.

The mechanism of Congo red binding to amyloid protein was studied in order to establish which of two structural dye versions present in water solutions--unimolecular and supramolecular--represent its actual ligation form. Immunoglobulin L chain lambda of amyloidogenic nature, expressed by Congo red binding and easy gel formation, was used as the model amyloid protein. Congo red was coassembled with rhodamine B, designed to be a marker of the Congo red micellar organisation in complexation with protein. The particular suitability of rhodamine B for this role results from significant difference in its binding affinity to Congo red and to protein. It associates readily with Congo red, becoming incorporated into its micellar organisation, but as homogenous dye it shows an almost complete inability to bind to protein. In view of these properties, Congo red was used as a vehicle to draw rhodamine B into complexation with protein, at the same time supplying evidence of its supramolecular ligation form. The results show that both soluble amyloid precursor L chain and the derived gel material attach rhodamine B coassembled with Congo red but not the homogenous rhodamine B. Despite its dynamic, supramolecular character, Congo red participates in complexation with amyloid proteins as an integral ligand unit.

Amyloid beta-Protein Precursor↗

PubMed2000

Application of similarity matrices and genetic neural networks in quantitative structure-activity relationships of 2- or 4-(4-Methylpiperazino)pyrimidines: 5-HT(2A) receptor antagonists.

Antagonists of the 5-HT(2A) receptor are being used to treat many psychiatric disorders. The present work focuses on a group of 27 antagonists possessing varying affinities toward the receptor. These are 26 title compounds and clozapine as a reference antagonist. The active conformers of the conformationally flexible ligands were proposed by using the active rigid analogue approach and performing similarity calculations. The calculations involved genetic neural network (GNN) computations deriving QSARs from similarity matrices (SM) with cross-validated correlation coefficients exceeding 0.92. The performance of neural networks with variety of architectures was studied. As the computations were performed for cations and neutral molecules separately, the relevance of the ligand charging is discussed.

Animals↗

PubMed2000

The conformational characteristics of Congo red, Evans blue and Trypan blue.

The structures of the closely related bis-azo dyes Evans blue, Trypan blue and Congo red, which appeared to have different self-assembly properties and correspondingly different abilities to form complexes with amyloids and some other proteins, were compared in this work. Ab initio and semi-empirical methods were used to find the optimal structures and partial charge distributions of the dyes. The optimal structures were searched using different widely used programs. The structures of Congo red and evans blue were found to be planar, except for the torsion on the central diphenyl bond connecting the two halves of the dye. Both symmetrical parts of the molecules appeared very close to planarity. However, Trypan blue exhibits non planarity on the di-azo bonds, as well as on the central bond between the symmetrical parts of the dye. In a consequence, the non planarity of this molecule is higher than in the case of its isomer, Evans blue and Congo red as well. The extra rotation around the azo bonds extorted by the close proximity of the sulfonic groups may be the direct cause of its poor self-assembling and complexation properties versus Evans blue.

Coloring Agents↗

PubMed2000

[Results of surgical treatment for acromioclavicular dislocation using a modified Mitchell method].

The paper presents the results of surgical treatment in acromioclavicular dislocation (grade III according to Tossy) in 53 patients. Joint reconstruction was performed using Mitchell's modified method--acromioclavicular reconstruction was achieved by applying a with Dallos poliester fiber prosthesis. Clinically in 90.5% of the cases a good or excellent result was achieved.

Acromioclavicular Joint↗

PubMed2000

[Analysis of causes for anemia in patients with multiple myeloma].

UNLABELLED: Pathogenetic mechanism of myeloma (MM) associated anaemia may involve: decreased level of erythropoietin (Epo) production, insufficient response to this hormone, bone marrow replacement by tumour cells, and cytokine mediated suppressive effect on erythropoiesis (ACD type of anaemia). We evaluated some possible causes of MM associated anaemia in a group of MM patients before treatment, using tests of in vitro culture of erythroid precursors and determination of the level of selected cytokines and evaluation of patient sera and media conditioned by patient cells for haematopoietic growth in vitro inhibitory/stimulatory activity. The study group included 15 patients with advanced MM at III clinical stage (according Durie and Salmon classification) prior treatment with a median age 61.8 women and 7 men. Diagnostic work-up included cytogenetics and serum Epo level as well as routine tests. We determined number of CFU-E, BFU-E and CFU-GM in the bone marrow of patients and healthy donors after mononuclear and T cell depletion in serum free culture under different conditions: 1) with conditioned medium (CM) by patients T cells, 2) CM by T cells of healthy donors and 3) without CM. IL-6, IL-1 alpha and TNF-alpha level in the serum and CM was determined. All patients were slightly anaemic--mean Hb 6 mmol/l (9.6 g/dl), transferrin level was increased--mean 1612 pmol/l (732 ng/ml) whereas iron level was normal. The average frequency of erythropoietic cells in myelogram was decreased (12%), however, the frequency of plasmocytes was increased (32%). Epo serum level was decreased in comparison with degree of anaemia (mean 22.2 U/ml). The average number of CFU-E/10(5) was slightly lower--212 and in the cultures containing CM by patient T cell and CM-by T cells of healthy donor decreased significantly to 138 and 183, accordingly. This phenomenon was not observed in cultures containing normal bone marrow cells. IL-6 level was increased in patients' serum and CM by patients T cells (27 ng/ml and 51 ng/ml, respectively). CONCLUSIONS: The results of this study support the notion on the multifactorial origin of anaemia in myeloma patients. The factors specified in this study include 1. defective response of Epo to the degree of anaemia 2. decreased number of committed erythroid cells in the marrow 3. suppression of erythropoiesis by IL-6.

Adult↗

PubMed1999

[The evaluation of the coronary artery sufficiency in myocardial infarction patients after cardiac surgery and preventive therapy].

During 5 years period (1989-1993) the authors investigated a group of 40 patients with coronary artery disease after myocardial infarction treated in the Silesian Center of Cardiology in Katowice. 20 patients were operated on (CABG), 20 were medically-treated. It was evaluated the history, physical status, stress-test, echocardiography and 24-hours ECG. Stress test was estimated according to Mark's test. In the echocardiographic examination it was observed wall motion score index (WMSI) and the left ventricular abnormal contraction area (AA). In the operated group it was noticed higher physical ability and no influence of CABG on left ventricular contractability.

Adult↗

PubMed1999

Supramolecularity creates nonstandard protein ligands.

Congo red and a group of structurally related dyes long used to stain amyloid proteins are known to associate in water solutions. The self-association of some dyes belonging to this group appears particularly strong. In water solutions their molecules are arranged in ribbon-like micellar forms with liquid crystalline properties. These compounds have recently been found to form complexes with some native proteins in a non-standard way. Gaps formed by the local distribution of beta-sheets in proteins probably represent the receptor sites for these dye ligands. They may result from higher structural instability in unfolding conditions, but also may appear as long range cooperative fluctuations generated by ligand binding. Immunoglobulins G were chosen as model binding proteins to check the mechanism of binding of these dyes. The sites of structural changes generated by antigen binding in antibodies, believed to act as a signal propagated to distant parts of the molecule, were assumed to be suitable sites for the complexation of liquid-crystalline dyes. This assumption was confirmed by proving that antibodies engaged in immune complexation really do bind these dyes; as expected, this binding affects their function by significantly enhancing antigen binding and simultaneously inhibiting C1q attachment. Binding of these supramolecular dyes by some other native proteins including serpins and their natural complexes was also shown. The strict dependence of the ligation properties on strong self-assembling and the particular arrangement of dye molecules indicate that supramolecularity is the feature that creates non-standard protein ligands, with potential uses in medicine and experimental science.

Animals↗

PubMed1998

Effect of serine proteinase inhibitors on intracellular free calcium rise in human polymorphonuclear leukocytes after stimulation with receptor agonists.

The respiratory burst of polymorphonuclear leukocytes depends on activation of many enzymes and generation of variety of second messengers. One of important links leading to polymorphonuclear leukocytes (PMNL) activation is a transient rise in intracellular free calcium concentration ([Ca2+]i). Serine proteinase inhibitors such as alpha-1-proteinase inhibitor (alpha1PI), phenylmethylsulphonylfluoride (PMSF) and soybean trypsin inhibitor (SBTI) were reported to inhibit human PMNL respiratory burst. In this study we tested the hypothesis whether these inhibitors can inhibit the rise in [Ca2+]i after stimulation of human PMNL with 10(-7) M n-formyl-methionyl-leucyl-phenylalanine (FMLP), leukotriene B4 (LTB4) or platelet activating factor (PAF). [Ca2+]i was measured with use of a fluorescent probe Fura-2AM under conditions of 100 nM and 1 mM extracellular Ca2+ concentration. Preincubation of PML with 600 mg/dl of alpha1PI or SBTI for 30 min at 37 degrees C had no influence on Ca2+ response to all agonists in comparison with cells treated with the same concentration of human serum albumin. However, 0.5 mM PMSF enhanced 1.7-fold (p < 0.002) [Ca2+]i rise after challenge with FMLP while did not affect significantly Ca2+ response to PAF and LTB4. The stimulatory effect of PMSF after addition of FMLP was dependent on increased Ca2+ influx from extracellular space. Our results suggest that suppression of PMNL respiratory burst by serine proteinase inhibitors is not mediated via Ca2+ pathway and that some proteases take part in Ca2+ response to FMLP.

Adult↗

PubMed1997

Increased hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients.

Symptoms of bronchial asthma are a manifestation of airway inflammation. Circulatory leucocytes (predominantly eosinophils, mast cells and neutrophils), release inflammatory mediators, including reactive oxygen species, i.e. superoxide anion which is dismutated to hydrogen peroxide (H2O2). Neutrophils from asthmatics generate greater amounts of these species than those of healthy subjects. Some of the H2O2 and thiobarbituric acid-reactive products (TBARs) can evaporate from alveolar lining fluid, and could be expired from the airways of asthmatics. In this study, therefore, we determined whether asthmatic patients exhale more H2O2 and TBARs than healthy subjects. We examined 10 healthy subjects as a control group and 21 asthmatic subjects. In asthmatic subjects, forced expiratory volume in one second (FEV1), was 68+/-9% of predicted value, peak expiratory flow rate (PEFR) was 65+/-8% pred, and bronchial reversibility was 34+/-5% of prebronchodilated FEV1. The mean H2O2 level measured spectrofluorimetrically in the expired breath condensate of asthmatic subjects was 26 fold higher than that in healthy controls (0.26+/-0.29 vs 0.01+/-0.03 nM; p<0.05). The concentration of TBARs in breath condensate was also higher in asthmatic patients compared with nonasthmatics (0.073+/-0.071 vs 0.004+/-0.009 nM; p<0.05). There was a significant correlation between H2O2 level and concentration of TBARs in asthmatic patients (r=0.74; p<0.01). There was also a strong inverse correlation between H2O2 content of all asthmatics and FEV1% pred (r=-0.63; p<0.005) and PEFR% pred (r=-0.52; p<0.05). We conclude that there are elevated levels of hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients, and that measurement of these substances in the expired breath condensate could be a simple, noninvasive method that could be used as a biochemical marker of airway inflammation.

Adult↗

PubMed1997

Pregnancy and delivery prognostic risk score for women with congenital heart disease and acquired valvular heart disease.

Hemodynamic changes related to pregnancy in women with Congenital Heart Disease (ConHD) or Acquired Valvular Heart Disease (AVHD) require special medical care during pregnancy and especially immediately prior to, and after delivery. Following a five year retrospective study (1978-1982), the authors monitored prospectively over a period of 12 years (1983-1994), 378 pregnancies in 252 women with ConHD and AVHD. Based on the results of the initial clinical examination and monthly follow-up visits, a numerical risk score was assigned for each patient. The study showed good conformity between the predictive risk score values and the patient's condition in the course of pregnancy and delivery. Thus, this method represents a novel and potentially very useful clinical tool for management of pregnancy in patients with ConHD and AVHD.

Abortion, Spontaneous↗

PubMed1997

[Zinc protoporphyrin (ZPP) in diagnosis of anemia].

In iron deficiency, zinc protoporphyrin (ZPP) is produced instead of heme, and the ZPP concentration in erythrocytes increased (normal value < 2.3 micrograms ZPP/g Hb). The ZPP level and comparison with the other normally used tests in iron deficiency in the group of the patients with iron deficiency, ACD, MDS, AML, plasmocytoma was investigated. The ZPP level was determined by hematofluorometry in samples from 96 patients. Thirty five patients with iron depletion showed decreased both serum ferritin (median 5.9 ng/ml), and hemoglobin level (median 9.8 g/dl) with significantly increased ZPP level (median 8.5 micrograms/gHb). An increased level of ZPP (median 3.95 micrograms/gHb) with normal level of ferritin (median 24 ng/ml) and iron (median 50 (g/dl) in the serum of patients with ACD was determined. Measurement of ZPP level in the combination with ferritin and peripheral blood morphology allows to classify the degree of iron deficiency. The ZPP levels higher than 4.55 micrograms/gHb confirms iron deficiency in the group of anaemic patients.

Anemia↗

PubMed1996

Changes of serum concentration of lipid peroxidation products in patients with pneumonia.

During lower respiratory tract infection, massive influx and activation of phagocytes is observed. Reactive oxygen species (ROS) released by macrophages and polymorphonuclear neutrophils (PMNs) kill microorganisms and cause damage to host tissues. One feature of this damage may be enhanced lipid peroxidation. Therefore, the aim of this study was to estimate the serum concentration of lipid peroxidation products in combination with clinical and biochemical indicators of inflammation in 32 patients with pneumonia. Serum concentration of lipid peroxides (CLP) and malondialdehyde (CMDA) was measured at Day 1, 4, 10 and 14 of observation, whilst chest radiography and routine blood analysis were performed at Day 1 and 14 during a 2 week treatment of lower airway infection. The CLP decreased during treatment (p < 0.05) from 0.059 +/- 0.024 to 0.043 +/- 0.017 (A532 nm) and the CMDA (p < 0.05) from 3.5 +/- 1.4 to 2.8 +/- 1.3 nmol.mL-1. A negative correlation between CLP and radiological regression (r = 0.49) and a drop in white blood cell count (WBC) (r = 0.39) was observed during the treatment. A positive correlation between CMDA and serum trypsin inhibitory capacity (STIC) (r = 0.47) and erythrocyte sedimentation rate (ESR) (r = 0.43) was found. Our data indicate that an enhanced process of lipid peroxidation occurs during pneumonia and that serum concentration of lipid peroxides returns to normal values quicker than the concentration of malondialdehyde during recovery. The use of antioxidants is suggested as an adjuvant treatment in patients with pneumonia.

Adult↗