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A Mazurek

Publications and source records attributed to A Mazurek.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of tumor angiogenesis and thymidine phosphorylase tissue expression in patients with endometrial cancer.

The formation of new blood vessels in endometrial cancer tissue is a main process, which leads to tumor progression, and is connected with tumor expansion and invasiveness. The aim of the study was evaluation of thymidine phosphorylase protein (TP) expression in human endometrial cancer cells by immunohistochemistry and comparison obtained data with intensity of angiogenesis process and clinicopathological factors as FIGO stage of disease and histopathologic grade. Endometrial cancer specimens were obtained from 55 postmenopausal patients (aged 52 to 74 years) underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy. None of patients received preoperative pelvic irradiation. Histopathological typing and grading of the endometrial tumors (G-1, G-2, G-3) as well as myometrial invasion (<1/2, >1/2) were assessed using standard criteria, on hematoxylin-eosin sections. At the surgery, FIGO clinical stage of disease was determined. Thymidine phosphorylase overexpression was observed in 23 of 55 (41.8%) cases of endometrial cancer. Although we found no statistically significant differences in TP expression between histopathologic grades, particular FIGO stages showed a significant trend of increase TP tumor overexpression. Thymidine phosphorylase overexpression cases demonstrate higher intensity of angiogenesis in comparison to negative samples and results are statistically significant for t-test (p<0.0001). The most intensive new blood vessel formation was observed in G-2 of tumor differentiation grade (p=0.013 for ANOVA test) Mean angiogenic points density (APD) values in cases of G-1 histopathologic grade reached 135.7; values of G-2 and G-3 grades reached 213.8 and 162.8, respectively. Mean intensity of angiogenesis in the first FIGO stage of disease reached 160.0 APD, in stage II 205.6 APD, and in the third 286.9, respectively. Angiogenesis was more intensive in cases of advanced tumors - analysis of variance (ANOVA) confirmed statistically significant differences in APD values between FIGO stage groups (p=0.0007). In conclusion, thymidine phosphorylase expression correlates with increased microvessel density in endometrial cancer. The intensity of angiogenesis process increases according to FIGO stage of disease, which is connected with progressing of cancer disease. Thymidine phosphorylase can play an important role in endometrial cancer progression and could offer additional information about advance of disease.

Aged↗
PubMed2004

Evaluation of angiogenesis, p-53 tissue protein expression and serum VEGF in patients with endometrial cancer.

Endometrial carcinoma occurs mostly in post-menopausal women. Classical methods of prognostication, as FIGO stage and histopathologic grade, could be improved by applying additional techniques, utilizing molecular biology and immunochemistry. p-53 tumor suppressor gene, the most commonly mutated gene in human cancers has been shown to play an important role in the biology of gynecologic carcinomas. Angiogenesis, a process of formation of new vessels, being connected to tumors progression and metastatic potential was shown to be linked with tumor suppressor genes expression. The aim of the study was to evaluate relationships between intensity of tumor angiogenesis, serum levels of Vascular Endothelial Growth Factor (VEGF) and tissue p-53 protein expression in endometrial adenocarcinoma. Angiogenic Point's Density (APD) was calculated in hot spots areas using the morphometric appliance. For detection of p53 protein in tumor samples, LSAB + Kit Alkaline Phosphatase (DAKO) was used. VEGF levels were assessed in patient's blood sampled before the operation. Overexpression of p53 protein was found in tumor tissue in 35.2% of cases and mean angiogenic points density was greater in p53 positive cases. Serum levels of VEGF were above the cut off level in 54.5% of patients, in those cases angiogenesis was also elevated. In cases of p53 overexpression, VEGF levels tended to be greater as compared with p53 negative cases. In conclusion, our study demonstrated that angiogenesis was more intensive in p53 positive cases, confirming the hypothesis of tumor suppressor-gene regulation of the process of neovascularization. Serum levels of VEGF were borderline-significantly higher in cases of p53 overexpression, they were also correlated to the angiogenesis. Joint assessment of angiogenesis and tumor suppressor genes expression may contribute to reliable evaluation of the biology of endometrial carcinoma.

Adenocarcinoma↗
PubMed2003

IGF-I triple helix gene therapy of rat and human gliomas.

PURPOSE: IGF-I anti-gene technology was applied in treatment of rat and human gliomas using IGF-I triple helix approach. MATERIAL AND METHODS: CNS-1 rat glioma cell and primary human glioblastoma cell lines established from surgically removed glioblastomas multiforme were transfected in vitro with IGF-I antisense (pMT-Anti-IGF-I) or IGF-I triple helix (pMT-AG-TH) expression vectors. The transfected cells were examined for immunogenicity (immunocytochemistry and flow cytometry analysis) and apoptosis phenomena (electron microscopy). 3 x 10(6) transfected cells were inoculated subcutaneously either into transgenic Lewis rats or in patients with glioblastoma. The peripheral blood lymphocytes (PBL) derived from "vaccinated" patients were immunophenotyped for the set of CD antigens (CD4, CD8 etc). RESULTS: Using immunocytochemistry and Northern blot techniques, the transfected "antisense" and "triple-helix" cells showed total inhibition of IGF. Transfected cultures were positively stained either for both MHC-I and B7 antigens--60% of cloned lines, or for MHC-I only--40% of cloned lines. Moreover "triple helix" cells as compared to "antisense" cells showed slightly higher expression of MHC-I or B7. Transfected cells also showed the feature of apoptosis in 60%-70% of cells. In in vivo experiments with rats bearing tumors, the injection of "triple helix" cells expressing both MHC-I and B7 interrupted tumor growth in 80% of cases. In contrast, transfected cells expressing only MHC-I stopped development in 30% of tumors. In five patients with surgically resected glioblastoma who were inoculated with "triple helix" cells, PBL showed an increased percentage of CD4 + CD25+ and CD8 + CD11b-cells, following two vaccinations. CONCLUSIONS: The anti-tumor effectiveness of IGF-I anti-gene technology may be related to both MHC-I and B7 expression in cells used for therapy. The IGF-I antigene therapy of human glioblastoma multiforme increases immune response of treated patients.

Animals↗
PubMed2002

Angiogenesis and Bcl-2 protein expression in patients with endometrial carcinoma.

Considering the particular importance of angiogenesis and tumor suppressor genes expression in solid tumors, angiogenesis and Bcl-2 protein expression were evaluated in order to specify their role in the biology of endometrial carcinoma. Clinical material comprised 66 patients (postmenopausal, aged 52 to 76 years) with endometrial adenocarcinoma. For evaluation of angiogenesis immunohistochemical method was applied using DAKO EPOS Anti-Human Von Willebrand Factor/HRP antibodies. Morphometric method was applied to count angiogenic points (microvessels + single endothelial cells), using a light microscope with morphometric appliance. Angiogenic points density (APD) was defined as the density of AP per square mm. Immunohistochemical staining for Bcl-2 cytosomic protein expression was performed using MoAb124 (dilution 1:80, Dako A/S, Denmark) monoclonal antibodies. The percentage of 10% positive cells was considered as Bcl-2 positive tissue expression. Positive cytoplasmic reaction of Bcl-2 in 51.3% of patients with Stage I endometrial cancer, and in 23.8% and 0% of patients with II and III FIGO stage, respectively, was observed. No relationship between Bcl-2 tissue cytoplasmatic expression and tumor grade was found. However, an inverse correlation between cytoplasmatic expression of Bcl-2 and FIGO stage was observed. The APD (angiogenic points density) was increasing with the clinical (FIGO) stage of endometrial cancer, but it was not observed in the case of tumor histologic grade. Bcl-2 expression and angiogenesis may be a useful parameter in evaluation of the biology of endometrial adenocarcinoma as the study conducted showed the influence of Bcl-2 protein expression upon angiogenesis.

Adenocarcinoma↗
PubMed2001

Adenosine nucleotide modulates the physical interaction between hMSH2 and BRCA1.

We have identified the physical interaction between the Breast Cancer susceptibility gene product BRCA1 and the Hereditary Non-Polyposis Colorectal Cancer (HNPCC) and DNA mismatch repair (MMR) gene product hMSH2, both in vitro and in vivo. The BRCA1-hMSH2 association involved several well-defined regions of both proteins which include the adenosine nucleotide binding domain of hMSH2. Moreover, the interaction of BRCA1 with purified hMSH2-hMSH6 appears to be modulated by adenosine nucleotide much like G protein downstream interaction/signaling is modulated by guanosine nucleotide. BARD1, another BRCA1-interacting protein, was also found to interact with hMSH2. In addition, BRCA1 was found to associate with both hMSH3 and hMSH6, the heterodimeric partners of hMSH2. These observations implicate BRCA1/BARD1 as downstream effectors of the adenosine nucleotide-activated hMSH2-hMSH6 signaling complex, and suggest a global role for BRCA1 in DNA damage processing. The functional interaction between BRCA1 and hMSH2 may provide a partial explanation for the background of gynecological and colorectal cancer in both HNPCC and BRCA1 kindreds, respectively.

Adenosine Diphosphate↗
PubMed2001

Immunoperoxidase detection of polycyclic aromatic hydrocarbon-DNA adducts in breast tissue sections.

Although the etiology of the majority of human breast cancers is unknown, environmental carcinogens are suspected to play a role. In this study, we investigated polycyclic aromatic hydrocarbon-DNA adducts in 78 breast cancer patients and benign breast disease patients with lifetime environmental exposure to polycyclic aromatic hydrocarbon (PAH) compounds. Adducts were detected in paraffin sections by immunoperoxidase method using polyclonal antiserum and were quantitated by the image-analyzing system. A significantly higher level of adducts was found in benign breast disease as compared to cancer patients (P < .001; Mann-Whitney U test). Neither smoking nor genetic polymorphisms in glutathione S-transferase and cytochrome P450 influenced the level of adducts. This exploratory study demonstrates the usefulness of the immunoperoxidase method to detect PAH-DNA adducts in stored breast tissue and suggests further research on a larger population, including patients from both high- and low-pollution environments.

Adult↗
PubMed2000

The effect of O6-methylguanine DNA adducts on the adenosine nucleotide switch functions of hMSH2-hMSH6 and hMSH2-hMSH3.

The human homologs of prokaryotic mismatch repair have been shown to mediate the toxicity of certain DNA damaging agents; cells deficient in the mismatch repair pathway exhibit resistance to the killing effects of several of these agents. Although previous studies have suggested that the human MutS homologs, hMSH2-hMSH6, bind to DNA containing a variety of DNA adducts, as well as mispaired nucleotides, a number of studies have suggested that DNA binding does not correlate with repair activity. In contrast, the ability to process adenosine nucleotides by MutS homologs appears to be fundamentally linked to repair activity. In this study, oligonucleotides containing a single well defined O(6)-methylguanine adduct were used to examine the extent of lesion-provoked DNA binding, single-step ADP --> ATP exchange, and steady-state ATPase activity by hMSH2-hMSH3 and hMSH2-hMSH6 heterodimers. Interestingly, O(6)-methylguanine lesions when paired with either a C or T were found to stimulate ADP --> ATP exchange, as well as the ATPase activity of purified hMSH2-hMSH6, whereas there was no significant stimulation of hMSH2-hMSH3. These results suggest that O(6)-methylguanine uniquely activates the molecular switch functions of hMSH2-hMSH6.

Adenosine Triphosphatases↗
PubMed1999

Synergistic activation of protein kinase Calpha, -betaI, and -gamma isoforms induced by diacylglycerol and phorbol ester: roles of membrane association and activating conformational changes.

Protein kinase Calpha (PKCalpha) has been shown to contain two discrete activator sites with differing binding affinities for phorbol esters and diacylglycerols. The interaction of diacylglycerol with a low-affinity phorbol ester binding site leads to enhanced high-affinity phorbol ester binding and to a potentiated level of activity [Slater, S. J., Ho, C., Kelly, M. B., Larkin, J. D. , Taddeo, F. J., Yeager, M. D., and Stubbs, C. D. (1996) J. Biol. Chem. 271, 4627-4631]. In this study, the mechanism of this enhancement of activity was examined with respect to the Ca2+ dependences of membrane association and accompanying conformational changes that lead to activation. The association of PKCalpha with membranes containing 12-O-tetradecanoylphorbol 13-acetate (TPA) or 1, 2-dioleoylglycerol (DAG), determined from tryptophan to dansyl-PE resonance energy transfer (RET) measurements, was found to occur at relatively low Ca2+ levels (</=1 microM). However, PKCalpha was found to be inactive even though membrane association was complete at these Ca2+ levels and further titration of Ca2+ to a concentration of approximately 100 microM was required for activation. This increase in Ca2+ concentration also led to a further increase in RET, which was due to a Ca2+-induced activating conformational change, as verified by an accompanying increase in the PKCalpha tryptophan fluorescence anisotropy. Coaddition of DAG and TPA resulted in a reduction in the Ca2+ levels required for both the conformational change and enzyme activation. Also, it was found that incubation of the enzyme with TPA alone resulted in a time-dependent increase in the Ca2+-independent PKCalpha activity, the rate and extent of which was further enhanced upon coaddition with DAG. Tauhe results suggest that the enhanced level of activity induced by coaddition of DAG and TPA involves both Ca2+-dependent and Ca2+-independent activating conformational changes which result in active conformers of PKCalpha distinct from those formed by interaction with either activator separately.

Anisotropy↗
PubMed1998

Inhibition of membrane lipid-independent protein kinase Calpha activity by phorbol esters, diacylglycerols, and bryostatin-1.

The activity of membrane-associated protein kinase C (PKC) has previously been shown to be regulated by two discrete high and low affinity binding regions for diacylglycerols and phorbol esters (Slater, S. J., Ho, C., Kelly, M. B., Larkin, J. D., Taddeo, F. J., Yeager, M. D., and Stubbs, C. D. (1996) J. Biol. Chem. 271, 4627-4631). PKC is also known to interact with both cytoskeletal and nuclear proteins; however, less is known concerning the mode of activation of this non-membrane form of PKC. By using the fluorescent phorbol ester, sapintoxin D (SAPD), PKCalpha, alone, was found to possess both low and high affinity phorbol ester-binding sites, showing that interaction with these sites does not require association with the membrane. Importantly, a fusion protein containing the isolated C1A/C1B (C1) domain of PKCalpha also bound SAPD with low and high affinity, indicating that the sites may be confined to this domain rather than residing elsewhere on the enzyme molecule. Both high and low affinity interactions with native PKCalpha were enhanced by protamine sulfate, which activates the enzyme without requiring Ca2+ or membrane lipids. However, this "non-membrane" PKC activity was inhibited by the phorbol ester 4beta-12-O-tetradecanoylphorbol-13-acetate (TPA) and also by the fluorescent analog, SAPD, opposite to its effect on membrane-associated PKCalpha. Bryostatin-1 and the soluble diacylglycerol, 1-oleoyl-2-acetylglycerol, both potent activators of membrane-associated PKC, also competed for both low and high affinity SAPD binding and inhibited protamine sulfate-induced activity. Furthermore, the inactive phorbol ester analog 4alpha-TPA (4alpha-12-O-tetradecanoylphorbol-13-acetate) also inhibited non-membrane-associated PKC. In keeping with these observations, although TPA could displace high affinity SAPD binding from both forms of the enzyme, 4alpha-TPA was only effective at displacing high affinity SAPD binding from non-membrane-associated PKC. 4alpha-TPA also displaced SAPD from the isolated C1 domain. These results show that although high and low affinity phorbol ester-binding sites are found on non-membrane-associated PKC, the phorbol ester binding properties change significantly upon association with membranes.

Allosteric Regulation↗
PubMed1998

Angiogenesis in endometrial cancer.

We evaluated the level of angiogenesis in endometrial adenocarcinoma and investigated the relationship between tumor vascularity and clinicopathological parameters. The level of angiogenesis in noninvaded uterine smooth muscle was also studied. Angiogenesis was studied in uteri of 29 post-menopausal women operated on for endometrial cancer. DAKO EPOS Anti-Human von Willebrand Factor/HRP antibodies were applied to mark endothelial cells. Both vessels and endothelial cells were counted on a light microscope equipped with computerized morphometric appliance. The highest density of vessels and endothelial cells was found in disease-free uterine smooth muscle tissue situated distant to the tumor. Density of vessels and endothelial cell counts were higher in the outer as compared to the central parts of the tumor. We found statistically significant differences in total angiogenic points' density between groups of various clinical FIGO staging, specifically between Ia and Ib, Ic, II. A positive correlation was found between the clinical stage of the disease (according to FIGO) and the total angiogenic points' density, density of endothelial cells and the density of vessels with viable lumen (counts/sq. mm calculated from the central parts of the tumor). These results suggest that the analysis of angiogenesis may be a useful biologic parameter and additional study of neovascularization in endometrial cancer is warranted.

Aged↗
PubMed1998

[Immunoregulatory mechanisms of action of intravenous gammaglobulin in Kawasaki syndrome].

Kawasaki Syndrome (KS) is an acute vasculitis in young children associated with the development of coronary artery abnormalities. KS has been reported to occur in over 40 countries including Poland. The etiology of this disease remains controversial. However, recent studies suggest a potential role of bacterial toxins (superantigens) in the immunopathogenesis of KS. Immunomodulatory benefit and potential toxin neutralisation by intravenous immune globulin (IVIG) support the hypothesis of superantigen-related activation of the immune system in KS. The prevalence of cardiovascular abnormalities can be significantly reduced by treating patients during the first 10 days of illness with high-dose of intravenous gammaglobulin. The following predominant and non-exclusive mechanisms of action have been proposed to account for the immunomodulatory effects of IVIG in Kawasaki and other immune-mediated diseases: (i) functional blockade of Fc receptor on monocytes/macrophages; (ii) modulation of the production of cytokines and cytokine antagonists; (iii) inhibition of complement mediated damage; (iv) neutralisation of bacterial toxins by specific antibodies; (v) neutralisation of circulating autoantibodies by complementary (e.g. anti-idiotypic) antibodies in IVIG. These observations provide an important information that early recognition and prompt treatment of this illness is critical for a successful outcome.

Child↗
PubMed1998

Clinical tumour markers in ovarian cancer.

Within past few years, the measurement of serological, histochemical and molecular genetic markers has had an increasing influence on clinical decisions about initial treatment and follow-up. This review presents data concerning the most studied and interesting markers in ovarian cancer. CA 125, CA 19.9, TATI, CASA, CEA, TPA, TPS and CYFRA21-1 are now the most widely used serological tumour markers for management of ovarian cancer patients. Ras oncogenes, C-erb2 proto-oncogene, p53 suppressor gene and Bcl-2 oncogene are examples of currently used molecular genetic markers. As histochemical markers-proliferation markers, flow cytometric analysis, thymidine labelling index, Ki-67 nuclear antigen or differentiation markers are nowadays the ones most often determined. Some of these markers might be useful adjuncts for monitoring response to therapy, including early detection of tumour reactivation to allow curative therapy and rapid detection of treatment failure. The study of these markers may also lead to a better understanding of the biological characteristics of ovarian cancer. Numerous tumour markers characterized in this paper have been recognized as promising prognostic factors. The information derived from studies of these markers also represents the most promising avenue towards new treatment strategies; nevertheless to validate these factors, prospective studies of a large patient population are needed.

Biomarkers, Tumor↗
PubMed1998

[Molecular markers in ovarian cancer].

Within past few years, the investigation of molecular genetic markers has had an increasing influence on clinical decisions about initial treatment and follow-up. This review presents data concerning the most studied and interesting molecular markers in ovarian cancer. p53 tumour suppressor gene, Bcl-2 oncogene, K-ras oncogene, c-erb2 proto oncogene, c-myc oncogene are examples of currently used molecular genetic markers. Some of these markers might be useful adjuncts for monitoring response to therapy, including early detection of tumour reactivation to allow curative therapy and rapid detection of treatment failure. The study of these markers may also lead to a better understanding of the biological characteristics of ovarian cancer. The information derived from studies of these markers also represents the most promising avenue towards new treatment strategies.

Biomarkers, Tumor↗
PubMed1997

Interaction of alcohols and anesthetics with protein kinase Calpha.

The key signal transduction enzyme protein kinase C (PKC) contains a hydrophobic binding site for alcohols and anesthetics (Slater, S. J., Cox, K. J. A., Lombardi, J. V., Ho, C., Kelly, M. B., Rubin, E., and Stubbs, C. D. (1993) Nature 364, 82-84). In this study, we show that interaction of n-alkanols and general anesthetics with PKCalpha results in dramatically different effects on membrane-associated compared with lipid-independent enzyme activity. Furthermore, the effects on membrane-associated PKCalpha differ markedly depending on whether activity is induced by diacylglycerol or phorbol ester and also on n-alkanol chain length. PKCalpha contains two distinct phorbol ester binding regions of low and high affinity for the activator, respectively (Slater, S. J., Ho, C., Kelly, M. B., Larkin, J. D., Taddeo, F. J., Yeager, M. D., and Stubbs, C. D. (1996) J. Biol. Chem. 271, 4627-4631). Short chain n-alkanols competed for low affinity phorbol ester binding to the enzyme, resulting in reduced enzyme activity, whereas high affinity phorbol ester binding was unaffected. Long chain n-alkanols not only competed for low affinity phorbol ester binding but also enhanced high affinity phorbol ester binding. Furthermore, long chain n-alkanols enhanced phorbol ester induced PKCalpha activity. This effect of long chain n-alkanols was similar to that of diacylglycerol, although the n-alkanols alone were weak activators of the enzyme. The cellular effects of n-alkanols and general anesthetics on PKC-mediated processes will therefore depend in a complex manner on the locality of the enzyme (e.g. cytoskeletal or membrane-associated) and activator type, apart from any isoform-specific differences. Furthermore, effects mediated by interaction with the region on the enzyme possessing low affinity for phorbol esters represent a novel mechanism for the regulation of PKC activity.

Alcohols↗
PubMed1994

Pediatric injury patterns.

Ten thousand pediatric deaths annually in the United States speak for themselves. There are distinctive patterns and peculiarities of pediatric injuries that are emerging mostly as a result of small epidemiological studies. Trauma research has been and continues to be grossly underfunded relative to its impact on society. Allocation of appropriate funding and the requisite tools must be made available so that targeted and effective prevention campaigns can be designed and vigorously implemented [50, 69-75]. We have started, but the bulk of the work remains to be done. In many instances we should look to other parts of the world for successful examples (United Kingdom, Germany, Australia) [37, 63, 76]. Greater emphasis must be placed on basic science research applicable to trauma and on clinical research designed to improve the care not only of injured children but of all trauma patients. While the need for a comprehensive response to the worldwide trauma epidemic remains at a whisper, we have started shouting.

Adolescent↗
PubMed1993

The pediatric patient in the post anesthesia care unit.

This article provides an overview of pediatric post anesthesia care. It highlights important aspects of care that are frequently encountered in practice or have the potential for being problematic. These include airway management, fluid maintenance, the treatment of seizures, thermoregulation, the management of malignant hyperthermia, the identification and treatment of emergence delirium, and the availability of appropriate emergency equipment and medications.

Child↗
PubMed1991

Pediatric trauma: overview of the problem.

Trauma in children claims more lives than any other childhood disease; (8,000 deaths were reported in the United States in 1989). The peculiar anatomy and physiology of the young body is responsible for the different pattern and distribution of injuries in children than in adults. For instance, 75% of multiply injured children suffer from head trauma. This implores early, aggressive airway management to prevent secondary hypoxic brain injury, which becomes a primary focus in treatment of the multiply injured child. Recent research indicates that care delivered by specially trained teams results in decreased morbidity associated with prehospital care and transport of these patients. Inpatient care of injured children ranges from highly sophisticated resuscitation and life support to postoperative pain control and tactful communication with distressed families. Physicians and nurses involved in trauma care must direct their efforts to further the education of medical personnel and the lay public regarding management of accident victims.

Adolescent↗