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Showing papers by "Gdańsk Medical University published in 1999"


Journal ArticleDOI
TL;DR: There is increasing evidence that PP2A activity is regulated by extracellular signals and during the cell cycle, and it is likely to play an important role in determining the activation kinetics of protein kinase cascades.

806 citations


Journal ArticleDOI
TL;DR: The parameters proposed quantitatively characterize the RP-HPLC stationary phases and provide a rational explanation for the differences in retention patterns of individual columns observed when applying the conventional empirical testing methods are proposed.

189 citations


Journal ArticleDOI
TL;DR: It is suggested that the formation of MG may be an adaptive process at a subcellular level to unfavorable environments: when cells are exposed to excess amounts of free radicals mitochondria become enlarged decreasing the rate of oxygen consumption, which will result in decreases in ROS production as shown in the present study.

147 citations


Journal ArticleDOI
TL;DR: The degree of contamination of Gulf of Aden waters by the metals studied is discussed and the potential ability of molluscs, especially A. haddoni and T. coronatus, as biomonitors of metallic pollutants is postulated.

141 citations


Journal ArticleDOI
TL;DR: There were no differences in outcome for patients with dialysis-dependent acute renal failure between those treated with Cuprophan membranes and those treating with polymethyl-methacrylate membranes, and the main outcome was survival 14 days after the end of therapy.

123 citations


Journal ArticleDOI
TL;DR: The correlation between the temporal duration of AD and both the decrease of the total number of granule cells and the volumetric loss of the molecular and granular layers indicates that cerebellar pathology, when viewed holistically, evolves continuously in association with clinical changes throughout the clinically manifest course of AD.

119 citations


Journal ArticleDOI
TL;DR: The morphology of the claustrum was studied by stereological methods in representatives of five mammalian orders (Insectivora, Rodentia, Lagomorpha, Carnivora and Primates) and differences in the morphology and cellular structure may suggest differences in function of the two parts of the nucleus.
Abstract: The morphology of the claustrum was studied by stereological methods in representatives of five mammalian orders (Insectivora, Rodentia, Lagomorpha, Carnivora and Primates). In each species under study, a dorsal and a ventral part of the nucleus can be distinguished. Based on differences in shape and separation from surrounding structures, five morphological types of the claustrum occur. The claustrum of Insectivora and some rodents represents the least complicated morphological type. The nucleus is very poorly separated from the surrounding structures. The human claustrum is morphologically the most complicated, although the two above-mentioned principal divisions are apparent. The ventrally situated paraamygdalar part of the human claustrum may correspond to the endopiriform nucleus or ventral part of the claustrum of other mammals, because of its morphological characteristics and connections with the limbic system. In guinea pigs, traditionally classified as members of the Rodentia, a characteristic morphological type of the claustrum is present. This observation may support arguments questioning the current position of this species in mammalian classification. Based on stereological studies, the increase of the claustral volume that occurs with increase of the hemispheric volume is significantly smaller than the increase of the isocortical volume and larger than the increase of the allocortical volume. The increase of the volume of the dorsal and ventral parts of the claustrum does not differ significantly in the species under study. Neurons of the claustrum represent differentiated morphology. The numerical density of neurons in the dorsal part of the claustrum is significantly higher than in the ventral one. Differences in the morphology and cellular structure of the two parts of the claustrum may suggest differences in function of the two parts of the nucleus, most probably concerned with transfer of information among various cortical regions. Changes in the claustrum, a cortico-related structure, that occur with increased brain volume, may suggest that its development is less dynamic than that of the isocortex.

112 citations


Journal ArticleDOI
TL;DR: The cloning and expression of cN-I provides definitive evidence of its ability to produce adenosine during ATP breakdown, and obtained a full-length clone encoding a novel 40-kDa peptide that was most abundant in heart, brain, and breast muscle.

93 citations


Journal ArticleDOI
TL;DR: The results show that HtrA plays a role in defense against oxidative shock and support the hypothesis that HTRA participates in the degradation of oxidatively damaged proteins localized in the cell envelope, especially those associated with the membranes.
Abstract: The serine protease HtrA (DegP), which is indispensable for cell survival at elevated temperatures, is a peripheral membrane protein, localized on the periplasmic side of the inner membrane in Escherichia coli, and the biochemical and genetic evidence indicates that the physiological role of HtrA is to degrade denatured proteins formed in the cellular envelope during heat shock. The aim of this study was to find out if the HtrA protease contributes to protection of the cell against oxidative stress. We compared the influence of various oxidizing agents on htrA mutant cells with their effects on wild-type bacteria, and found that the htrA mutation did not increase sensitivity to hydrogen peroxide or paraquat but made the cell extremely sensitive to ferrous [Fe(II)] ions, which are known to enhance oxidation of proteins. Treatment with ferrous ions caused a larger increase in the level of protein carbonyl groups in the membrane fraction of the cell than in the periplasm and cytoplasm. Iron-induced oxidation of membrane proteins was enhanced in the htrA mutant relative to wild-type cells. Inhibition of the growth of the htrA mutant by iron could be alleviated more efficiently by a nitroxide antioxidant that localizes in the membranes (A-TEMPO) than by a derivative (40H-TEMPO) that acts mainly in the soluble fraction of the cell. Inhibition of the growth of the htrA mutant was more pronounced following treatment with cumene hydroperoxide, which partitions into membranes, than with t-butyl hydroperoxide, which forms radical mainly in the cytosol. Both ferrous ions and cumene hydroperoxide, but not hydrogen peroxide, paraquat or t-butyl hydroperoxide, induced synthesis of HtrA. Our results show that HtrA plays a role in defense against oxidative shock and support the hypothesis that HtrA participates in the degradation of oxidatively damaged proteins localized in the cell envelope, especially those associated with the membranes.

87 citations


Journal ArticleDOI
TL;DR: This study has examined computer simulation errors that can arise from inexact expressions for retention time as a function of T, tG or isocratic %B, applicable to both complex and simpler samples, in either one- or two-dimensional optimization.

79 citations


Journal ArticleDOI
TL;DR: In this paper, the concentrations of 22 trace elements plus the rare earth elements (REE) were determined in the Sb (7.5) > As (5.8) ≥ Cd(5.2) > Pb (3.7), albeit with large variability in concentration in the sediments from one station to another.


Journal ArticleDOI
TL;DR: In this paper, the physicochemical properties of a laboratory-synthesized packing material for high-performance liquid chromatography (HPLC) containing cholesterol moiety immobilized on silica matrix were studied.

Journal ArticleDOI
TL;DR: Three model series of nonionized in water analytes are proposed for objective interlaboratory comparisons of effects on chromatographic separations of the stationary and the mobile phases by means of the analysis of quantitative structure-retention relationships (QSRR).
Abstract: Three model series of nonionized in water analytes are proposed for objective interlaboratory comparisons of effects on chromatographic separations of the stationary and the mobile phases by means of the analysis of quantitative structure−retention relationships (QSRR). Each series was designed specifically for a given general QSRR model by selecting the analytes whose properties were well reflected by the respective structural descriptors. Rules of a meaningful chemometric analysis were observed, and the structural information content was compromised with the length of analyte series. Three QSRR models were verified and are recommended for studies of molecular mechanism of chromatographic retention: the reduced linear solvation energy relationship-based model of Abraham, a model employing structural descriptors from molecular modeling, and a model correlating retention to the 1-octanol−water partition coefficient, log P. All the models were demonstrated to provide reliable QSRR equations for five sets o...

Journal ArticleDOI
TL;DR: The principles and methodology of studies of quantitative structure–retention relationships (QSRR) employing biomacromolecules and which bio-mimic molecules as active components of the separation systems are presented.
Abstract: Chemometrically processed retention parameters provide information on drug analytes which is of direct relevance for medicinal chemistry and molecular pharmacology. The principles and methodology of studies of quantitative structure–retention relationships (QSRR) employing biomacromolecules and which bio-mimic molecules as active components of the separation systems are presented.

Journal ArticleDOI
TL;DR: Genetic factors are major determinants of plasma leptin levels in humans and may account for as much as half of the variance in leptin levels.
Abstract: OBJECTIVE To examine the influence of genetic factors on plasma leptin levels. SUBJECTS AND METHODS We measured plasma leptin levels, body mass index and body fat distribution in healthy young female monozygotic (n = 19) and dizygotic (n = 14) twins. The twin zygosity was verified by determination of short tandem repeat and amplified fragment length polymorphism systems. The genetic analysis included analysis of variance-based and maximum likelihood-based methods. RESULTS Plasma leptin levels were correlated significantly with body mass index (r = 0.59, P < 0.001), waist circumference (r = 0.54, P < 0.001) and hip circumference (r = 0.63, P < 0.001), but not with age (r = -0.17) or the waist:hip ratio (r = 0.02). The heritability estimates derived from intraclass correlations were significant for body mass index (P = 0.001), waist circumference (P = 0.004), hip circumference (P = 0.01) and plasma leptin levels (P = 0.005), but not for the waist:hip ratio (P = 0.22). In the maximum likelihood-based path analysis, heritability was estimated at 79% for body mass index and at 73% for plasma leptin levels. After adjustment for body mass index, the heritability estimate for leptin levels from the model-fitting approach was 55%. CONCLUSIONS Genetic factors are major determinants of plasma leptin levels in humans and may account for as much as half of the variance in leptin levels.

Journal ArticleDOI
TL;DR: Despite recent developments, treatment outcomes in advanced NSCLC remain far from satisfactory, and new effective means are desperately needed if more patients are to enjoy the prospects of long-term survival.

Journal ArticleDOI
TL;DR: Results indicate that heart rate recorded over the 24 hours has a better reproducibility than office heart rate, and could thus be a better prognostic indicator than traditional measurement of resting heart rate in the hospital setting.

Journal ArticleDOI
TL;DR: The absence of any RR interval prolongation following phenylephrine induced baroreceptor stimulation demonstrates that vagal efferent reinnervation of the donor heart does not occur up to 24 months in patients operated via the standard Lower-Shumway procedure.
Abstract: Background: Orthotopic heart transplantation results in cardiac denervation. The presence of cardiac parasympathetic reinnervation in humans has been widely debated based on the application of differing indirect measures of autonomic control. However no attempt has been made to analyse the reflex heart rate response to baroreceptor stimulation whose occurrence is generally considered a reliable marker of the ability to activate cardiac vagal reflexes. This study tested the hypothesis that the presence of donor heart RR interval lengthening following phenylephrine induced blood pressure increase would be an index of parasympathetic reinnervation. Methods Baroreflex sensitivity (BRS) was assessed in 30 patients (mean age 51 ± 12 years) 1–24 months after heart transplantation carried out by the standard Lower-Shumway technique. In 6 patients the recipient atrium rate response (P-P interval) to baroreceptor stimulation by phenylephrine was also simultaneously determined by transesophageal recording. Results None of the 30 patients showed prolongation of RR intervals in the donor heart. The average BRS value was −0.28 ± 0.54 ms/mmHg (range −1.3–0.7 ms/mmHg). In the 6 patients in whom BRS was obtained at both the recipient atrium (P-P) and donor heart (R-R) the changes were 7.6 ± 5.7 ms/mmHg and −0.38 ± 0.58 ms/mmHg respectively ( p = 0.02), thus confirming that the absent RR interval lengthening in the donor heart is the consequence of efferent vagal fiber interruption. Conclusions The absence of any RR interval prolongation following phenylephrine induced baroreceptor stimulation demonstrates that vagal efferent reinnervation of the donor heart does not occur up to 24 months in patients operated via the standard Lower-Shumway procedure. It is also suggested that analysis of baroreceptor reflexes is a more specific method in the examination of cardiac parasympathetic reinnervation.

Journal ArticleDOI
TL;DR: Protective effects of cycloheximide, which enhances the expression of Bcl-2 protein, may further confirm the hypothesis that the megamitochondria formation is a cellular response to an increased ROS generation and raise a possibility that antiapoptotic action of the drug is exerted via the protection of the mitochondria functions.

Journal ArticleDOI
Piotr Szefer1, K. Ikuta, K. Frelek1, I. Zdrojewska1, M. Nabrzyski1 
TL;DR: From the data obtained, results that the soft tissue and especially byssi of M. edulis appear to be good bioindicators for identification of coastal areas exposed to Hg contaminants are apparent.

Journal ArticleDOI
TL;DR: A retrospective evaluation of survival and patterns of failure in 317 consecutive endometrial cancer patients treated between 1974 and 1991 with surgery and adjuvant radiotherapy finds a relatively high rate of extrapelvic recurrences calls for effective systemic adjuvants to surgery.
Abstract: . Jereczek-Fossa B, Badzio A, Jassem J. Surgery followed by radiotherapy in endometrial cancer: analysis of survival and patterns of failure. We performed a retrospective evaluation of survival and patterns of failure in 317 consecutive endometrial cancer patients treated between 1974 and 1991 with surgery and adjuvant radiotherapy. Two hundred and forty seven patients (78%) had FIGO stage I disease, 30 (9%) – stage II, 35 (11%) – stage III and 5 (2%) – stage IV. Both low dose rate brachytherapy (BRT) and external beam radiation (EBRT) were applied in 247 patients (78%), only BRT in 49 (15%), and only EBRT in 21 (7%). Median follow-up was 7.3 years. Five-year overall survival was 75%, and five-year disease free survival was 81%. Both overall and disease free survival rates were correlated with stage (P = 0.001 and P = 0.000, respectively). Recurrence occurred in 70 patients (22%): 11 (3.5%) in the pelvis, 51 (16%) outside the pelvis and 6 (2%) both in- and outside the pelvis. Independent risk factors for local recurrence included older age (P = 0.03) and variant histologic subtypes (P = 0.039), whereas independent risk factors for distant spread were stage (P = 0.000) and older age (P = 0.011). Normalized Total Dose (the sum of EBRT and BRT doses, based on linear-quadratic equation), type of radiotherapy regimen, overall radiotherapy time and surgery-to-radiotherapy interval did not correlate with the risk of relapse. Severe early and late radiotherapy complications were observed in 21 (7%) and 35 patients (11%), respectively. In view of the relatively low risk of exclusive pelvic recurrences and the high rate of severe late radiotherapy complications, indications for postoperative radiotherapy and its scheme should be verified. A relatively high rate of extrapelvic recurrences calls for effective systemic adjuvants to surgery. Further definition of high risk patients is warranted in order to tailor postoperative therapy to the prognostic factors and to increase the therapeutic index of management of endometrial cancer.

Journal ArticleDOI
TL;DR: Using the spin labelling method, changes in the structure and dynamics of molecular mobility in the plasmatic membrane accompanied by a spontaneous alteration of a melanotic melanoma line into an amelanotic form with a higher growth rate, changed antigenicity and immunogenicity are studied.

Journal ArticleDOI
TL;DR: The results indicate that the deterioration of health status is a prerequisite for an exaggerated TNF alpha production by peripheral blood mononuclear cells of people between the sixth and seventh decades of life.

Journal ArticleDOI
TL;DR: Both SUNCT syndrome and idiopathic stabbing headache (ISH) (jabs and jolts syndrome) have to be considered when encountering shortlasting headaches.
Abstract: Both SUNCT syndrome and idiopathic stabbing headache (ISH) (jabs and jolts syndrome) have to be considered when encountering shortlasting headaches. Since there are no specific tests for these headaches, the differential diagnosis depends entirely upon assessment of the clinical features. These headaches are generally easily distinguishable clinically. There seem to be symptomatic forms of SUNCT.

Journal ArticleDOI
TL;DR: It is concluded that pilocarpine in submicron emulsion is not protected against degradation, and the physical stability of the vehicle was easily destabilized during autoclaving or at room temperature.

Journal ArticleDOI
TL;DR: Elevated levels of tissue Pb, Cr, and Hg in the Etang des Eaux Blanches, an area adjacent to the harbor and highly industrialized region, are likely of anthropogenic origin.
Abstract: The concentrations of Ag, Cd, Co, Cr, Cu, Ni, Pb, Zn, Mn, and Fe in the soft tissue of the cockle Cerastoderma glaucum from six sites along the Mediterranean Lagoon Etang de Thau were determined by AAS; Hg was determined by the cold-vapor technique. Significant spatial variations in metal concentrations within the lagoon were recorded. Elevated levels of tissue Pb, Cr, and Hg in the Etang des Eaux Blanches, an area adjacent to the harbor and highly industrialized region, are likely of anthropogenic origin. Seasonally dependent variations in the tissue concentrations of trace elements at Crique de l'Angle were observed. The highest levels of Cr and Pb in the tissue were identified in March 1992, of Hg, Co, and Fe in period August 1990-January 1991, of Mn in August 1992, and Ag in January 1991. The gills contained the maximum amounts of Co and Ni, the mantle the most Fe and Hg, and the digestive gland (hepatopancreas) had most Cu.

Journal ArticleDOI
TL;DR: Addition of rhEPO in vitro to the whole blood cell cultures of the HD patients before implementation of erythropoietin confirmed thatrhEPO is able to directly stimulate IL-2 production, and studies show that the therapy with rhEPo affectsIL-2 secretion.
Abstract: The impairment of function of human T lymphocytes, leading to an inappropriate cytokine production, is partially responsible for defective immunological response in hemodialysis patients (HD). Recent data suggest that recombinant human erythropoietin (rhEPO) may exert immunological effects. The aim of this study was to find out whether rhEPO treatment of the HD patients may have an effect on the interleukin 2 (IL-2) production by their whole blood cell cultures. The study was carried out in 10 HD patients receiving rhEPO for 6 months. Compared with the levels seen before the treatment, the concentration of IL-2 increased in the phytohemagglutinin-stimulated whole blood cell cultures of 7 of 10 patients under study. Addition of rhEPO in vitro to the whole blood cell cultures of the HD patients before implementation of erythropoietin confirmed that rhEPO is able to directly stimulate IL-2 production. Our studies show that the therapy with rhEPO affects IL-2 secretion.

Journal ArticleDOI
TL;DR: It is proposed that binding of PLC-delta3 to PA may serve as a mechanism for dynamic membrane association and modulation of PLSD activity by interaction with the PH domain of the enzyme.
Abstract: In order to acquire an understanding of phospholipase C–δ3 (PLC–δ3) action on substrate localized in lipid membrane we have studied the binding of human recombinant PLC–δ3 to large, unilamellar phospholipid vesicles (LUVs). PLC-δ3 bound weakly to vesicles composed of phosphatidylcholine (PtdCho) or PtdCho plus phosphatidylethanolamine (PtdEtn) or phosphatidylinositol (PtdIns). The enzyme bound strongly to LUVs composed of PtdEtn + PtdCho and phosphatidylinositol 4,5-bisphosphate (PtdInsP2). The binding affinity (molar partition coefficient) of PLC-δ3 to PtdEtn + PtdCho + PtdInsP2 vesicles was 7.7 × 105m−1. High binding of PLC-δ3 was also observed for LUVs composed of phosphatidic acid (PA). Binding of PLC-δ3 to phosphatidylserine (PtdSer) vesicles was less efficient. Calculated molar partition coefficient for binding of PLC-δ3 to PA and PtdSer vesicles was 1.6 × 104 m−1 and 9.4 × 102 m−1, respectively. Presence of PA in the LUVs containing PtdInsP2 considerably enhanced the binding of PLC-δ3 to the phospholipid membrane. Binding of PLC-δ3 to phospholipid vesicles was not dependent on Ca2+ presence. In the liposome assay PA caused a concentration-dependent increase in activity of PLC-δ3. The stimulatory effect of PA on PLC-δ3 was calcium-dependent. At Ca2+ concentrations lower than 1 µm, no effect of PA on the activity of PLC-δ3 was observed. PA enhanced PLC-δ3 activity by increasing the Vmax and lowering Km for PtdInsP2. As the mol fraction of PA increased from 0–40 mol% the enzyme Vmax increased 2.3-fold and Km decreased threefold. Based on the results presented, we assume that PA supports binding of PLC-δ3 to lipid membranes by interaction with the PH domain of the enzyme. The stimulatory effect of PA depends on calcium-dependent interaction with the C2 domain of PLC-δ3. We propose that binding of PLC-δ3 to PA may serve as a mechanism for dynamic membrane association and modulation of PLC-δ3 activity.

Journal ArticleDOI
TL;DR: Thirteen patients with locally recurrent, previously-irradiated nasopharyngeal carcinoma were treated with linac-based hypofractionated stereotactic radiotherapy and three patients were free of disease at 30, 34 and 65 months.