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J Komorowski

Publications and source records attributed to J Komorowski.

At least 19 recordsLinked to original sources

Effects of hormone replacement therapy type and route of administration on plasma matrix metalloproteinases and their tissue inhibitors in postmenopausal women.

BACKGROUND: Matrix metalloproteinases (MMPs) are implicated in numerous disease states including cardiovascular disease and cancer. Because recent studies have shown a detrimental effect of hormone replacement therapy on cardiovascular disease and breast cancer, we investigated whether there are any differences in the concentrations of MMPs and their tissue inhibitors (TIMPs) in women receiving various forms of postmenopausal therapy. MATERIAL AND METHODS: A total of 195 healthy postmenopausal women were assessed: 46 were taking tibolone, 47 were taking transdermal estradiol, 46 were taking conjugated equine estrogens (CEE), and 56 were not taking any menopausal therapy (CTR). Plasma levels of MMP-2 and -9 and TIMP-1 and TIMP-2 were measured by ELISA methods. RESULTS: MMP-9 levels were significantly higher in the CEE group in comparison with healthy women not receiving menopausal therapy (P < 0.05). In contrast, MMP-9 levels in the tibolone group were significantly lower than in any other group (P < 0.01, compared with transdermal estradiol and CTR, and P < 0.001, compared with CEE). MMP-9 to TIMP-1 ratio was also significantly higher in the CEE, compared with CTR (P < 0.05), and lower in the tibolone group (P < 0.01, compared with all groups). MMP-2 levels were higher in the CEE group, compared with healthy women not receiving any menopausal therapy, and women taking tibolone (P < 0.05). CONCLUSIONS: Our study demonstrates differential effects of various forms of postmenopausal therapy on serum levels of MMP-9 and MMP-2. It remains to be established whether these differences might be associated with differences in risks of cardiovascular disease and cancer in these women.

Administration, Cutaneous↗

Increased circulating levels of matrix metalloproteinase-2 and -9 in women with the polycystic ovary syndrome.

INTRODUCTION: Matrix metalloproteinases (MMPs) have been implicated in various pathological processes including inflammatory response, cardiovascular disease, and recently also in ovarian dysfunction. Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age and is characterized by chronic anovulation, insulin resistance, and increased prevalence of cardiovascular risk factors. Circulating levels of MMPs and their tissue inhibitors (TIMPs) so far have not been assessed in the PCOS. MATERIALS AND METHODS: Serum levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured in 23 women with PCOS [age (mean +/- sd), 30.5 +/- 6.7 yr; body mass index, 35.8 +/- 7.5 kg/m2] and 22 healthy, regularly menstruating women (age, 29.4 +/- 5.6; body mass index, 31.7 +/- 9.2 kg/m2). RESULTS: Women with PCOS had significantly higher concentrations of MMP-2 (999.8 +/- 155 vs. 521.8 +/- 242 ng/ml; P < 0.001), MMP-9 (592.4 +/- 279 vs. 345 +/- 309; P = 0.007), and TIMP-1 levels (823.8 +/- 145 vs. 692 +/- 210 ng/ml; P = 0.02) than control healthy women. There was no difference in TIMP-2 levels (47.3 +/- 30 vs. 44.4 +/- 39.7 ng/ml; P = 0.21) between women with PCOS and controls. CONCLUSIONS: Obese women with PCOS have elevated serum concentrations of MMP-2 and -9. It might be hypothesized that elevated MMP concentrations may be related to increased cardiovascular risk in PCOS and/or menstrual irregularities associated with this syndrome.

Adult↗

Effect of the growth hormone-releasing hormone [GHRH(1-44)NH2] on IL-6 and IL-8 secretion from human peripheral blood mononuclear cells in vitro.

OBJECTIVE: Bidirectional communication between the neuroendocrine and immune systems is now a subject of an intensive investigation. Growth hormone-releasing hormone (GHRH) is synthesized by the hypothalamus, but is present also in the immune cells. Some recent data indicate also an immunomodulatory role of the neuropeptide. The aim of the study was to examine the influence of GHRH(1-44)NH2 on interleukin-6 and interleukin-8 secretion from human peripheral blood mononuclear cells cultured in vitro. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated by centrifugation using Böyum technique and cultured in a humidified atmosphere of 5 % CO2 and 95 % O2 at 37 degrees C for 24 hours in the presence of lipopolysaccharide (LPS) at the concentration of 2 microg/ml and GHRH(1-44)NH2 (the final neuropeptide concentrations to be tested were 10(-12) to 10(-6) M). ELISA methods were used to measure IL-6 and IL-8 concentrations in the supernatants of cultured cells RESULTS: GHRH(1-44)NH2 influenced IL-6 secretion from cultured cells, but significant inhibition of IL-6 release was observed at 10-6 M (p < 0.001). The negative correlation between the GHRH concentration studied and the IL-6 level in the supernatants was found (r = -0.759; p < 0.001). GHRH had no influence on the secretion of IL-8 from activated PBMC. CONCLUSIONS: Our results demonstrate that GHRH in vitro modulates IL-6 secretion from the human peripheral blood mononuclear cells, without any significant effect on IL-8 secretion.

Adult↗

Effect of growth hormone-releasing hormone (GHRH) and GHRH antagonist (MZ-4-71) on interferon-gamma secretion from human peripheral blood mononuclear cells in vitro.

Numerous reports indicate close interactions between the neuroendocrine and the immune systems. Hypothalamic neuropeptide, growth hormone-releasing hormone (GHRH) stimulates growth hormone (GH) secretion from the anterior pituitary gland, but recently some immunomodulatory properties of this peptide have also been demonstrated. In the present studies we evaluated the effect of human synthetic GHRH(1-44)NH(2) and GHRH antagonist (MZ-4-71) on interferon (IFN)-gamma secretion from human peripheral blood mononuclear cells (PBMC). GHRH(1-44)NH(2) at 10(-10), 10(-8) and 10(-6) M concentrations significantly (p < 0.05) increased the IFN-gamma level in supernatants of cultured cells, as compared with the controls. GHRH antagonist (MZ-4-71) at 10(-10), 10(-8) and 10(-6) M concentrations diminished the IFN-gamma level in supernatants in a dose-dependent manner, but statistically significant differences were observed only at 10(-8) M and 10(-6) M (p < 0.05 vs controls). Our results demonstrate that GHRH and GHRH antagonist MZ-4-71 can modulate IFN-gamma secretion in vitro by human peripheral blood mononuclear cells.

Adult↗

Effect of thyroliberin on the course of experimental candidosis in mice.

Thyroliberin (TRH) is one of the hormones, which affect immunologic processes. This hormone was studied in experimental subacute candidosis in mice. BALB/c males were given intraperitoneally single dose of Candida albicans cells (1 x 10(7) to 1 x 10(9) cfu of strain no. 244-33 ATCC). The animals from the experimental groups were injected subcutaneously, after 24 h from inoculation, dose of 10 microg TRH in 0.2 ml 0.9% NaCl, seven times at 24 h intervals. The control animals were given respectively 0.2 ml of physiologic NaCl solution. We have found that the examined hormone significantly decreases mortality in these animals (LD50 C. albicans for mice treated with TRH was three times higher than that in the control groups), prolongs mean survival time for mice and decreases the intensity of fungal invasion of the animal organs.

Animals↗

Soluble intracellular adhesion molecules (sICAM-1, sVCAM-1) in peripheral blood of patients with thyroid cancer.

The growth of a neoplasm and its ability to form metastases is a multistep process dependent on angiogenesis and immunological reactions of the organism. In this process adhesive factors are also involved. The aim of this work was estimation of the concentration of soluble intercellular adhesion molecules (sICAM-1) and vascular cellular adhesion molecules (sVCAM-1) in the serum of peripheral blood of patients with thyroid cancer before operation. The study comprised 48 patients ( 38 women and 10 men) aged from 18 to 87 years, in whom thin needle aspiration biopsy revealed cancer of the thyroid. Postoperative histopathological examination showed papillary cancer in 35 patients, oxyphilic cancer in 5 patients, anaplastic cancer in 4 and medullary cancer in 4 patients. In those patients, using the immunoenzymatic method ELISA, the concentration of sICAM-1 and sVCAM-1 in the serum of peripheral blood was determined. The control group comprised 26 healthy persons. We found statistically significant increase of sICAM-1 concentration in serum in all forms of cancer, in comparison with the control group. Mean concentrations of sICAM-1 were as follows: in papillary cancer patients 455.23+/-28.66 vs. 299.62+/-11.54 ng/ml, p<0.05; in oxyphilic cancer 455.60+/-95.21 vs. 299.62+/-11.54 ng/ml, p<0.05; in anaplastic cancer 570.00+/-170.89 vs. 299.62+/-11.54 ng/ml, p<0.05; and in medullary cancer 512.00+/-11.46 vs. 299.62+/-11.54 ng/ml, p<0.05. The mean concentration of sVCAM-1 in serum was statistically significantly higher than in the control group only in case of anaplastic cancer (1033.75+/-86.30 vs. 644.58+/-27.30 ng/ml; p<0.05). We evaluated the correlation coefficient between the concentration of sICAM-1 and sVCAM-1 in the serum of patients with thyroid cancer. Positive correlation was observed between the concentration of sICAM-1 and sVCAM-1. The obtained results confirm essential role of the investigated adhesive factors in the process of thyroid cancer growth.

Adolescent↗

GH-RH antagonist (MZ-4-71) inhibits VEGF secretion and proliferation of murine endothelial cells.

Angiogenesis plays a key role in solid tumor formation, invasiveness and metastasis. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that is necessary in the process of neovascularisation. Antagonists of growth hormone-releasing hormone (GH-RH) have been shown to suppress both in vivo and in vitro growth and metastasis of many human cancer cell lines. The mechanisms that mediate the antitumorigenic actions of these antagonists involve direct and indirect pathways, but are not completely elucidated. We have examined the effect of GH-RH antagonist MZ-4-71 on proliferation activity and VEGF release from cultured murine endothelial cells HECa10 in vitro. MZ-4-71 at 10(-8) to 10(-6) M concentrations inhibited the proliferative activity of cultured cells and suppressed the release of VEGF into supernatants of 72 h endothelial cell cultures. To our knowledge this is the first study reporting antiangiogenic properties of GH-RH antagonists.

Animals↗

Angiogenesis of endocrine gland tumours--new molecular targets in diagnostics and therapy.

Angiogenesis is one of the key stages in the development of neoplastic tumours, in which a small group of mutated cells transforms into a large malignant tumour metastasising to the neighbouring tissues and organs. The studies on the significance of neoangiogenesis in the progression of endocrine gland neoplasms have recently become one of the most rapidly evolving branches of molecular endocrinology. The induction of angiogenesis has been demonstrated to result from the imbalance between positive and negative factors which control this process. Our paper presents the results of current studies on the role of factors such as molecular markers of angiogenesis (e.g. vascular endothelial growth factor and basic fibroblast growth factor), metalloproteinases (which regulate the decomposition of the extracellular matrix) and their inhibitors, and adhesive molecules (e.g. soluble vascular cellular adhesion molecule-1 and soluble intracellular adhesion molecule-1) in the pathogenesis and diagnostics of endocrine gland tumours in humans. Also, we discuss new therapeutic strategies for inhibiting the growth of neoplasms by blocking the formation of blood vessels using angiogenesis antagonists, which inhibit various stages of angiogenesis. More and more data are being accumulated suggesting that these preparations could, in the near future, be used in the pharmacotherapy of some endocrine gland neoplasms.

Clinical Trials as Topic↗

[New knowledge derived from measurement of gene expression with the DNA microarray method].

BACKGROUND: The cDNA microarray method offers the first possibility of obtaining a global understanding of biological processes in living organisms, by simultaneous read-outs of tens of thousands of mRNAs. Initial experiments suggest that genes with similar function have similar expression patterns. MATERIAL AND METHODS: Understanding this level of biological complexity will, however, require completely new approaches to data analysis. Computer science methods, such as data mining and knowledge discovery, can synthesize interpretable if-then rules that model the relation between gene expressions and functions and use the rules to classify unknown genes. The huge body of existing biological and medical knowledge makes it necessary to develop methods for extracting knowledge from such repositories. RESULTS: Models of relations between gene expressions and gene functions in a data set from a publicly available source are synthesized semiautomatically and applied to classify unknown genes. Encouraging results have been achieved. The method is applied in the analysis of data from our microarray system which has recently become operational. INTERPRETATION: The principles are of general importance and will be used to evaluate a wide range of complex data sets like decision support in clinical medicine, for situations in which physicians need to handle a large volume of data for each patient.

Computational Biology↗

A literature network of human genes for high-throughput analysis of gene expression.

We have carried out automated extraction of explicit and implicit biomedical knowledge from publicly available gene and text databases to create a gene-to-gene co-citation network for 13,712 named human genes by automated analysis of titles and abstracts in over 10 million MEDLINE records. The associations between genes have been annotated by linking genes to terms from the medical subject heading (MeSH) index and terms from the gene ontology (GO) database. The extracted database and accompanying web tools for gene-expression analysis have collectively been named 'PubGene'. We validated the extracted networks by three large-scale experiments showing that co-occurrence reflects biologically meaningful relationships, thus providing an approach to extract and structure known biology. We validated the applicability of the tools by analyzing two publicly available microarray data sets.

Computer Communication Networks↗

Predicting gene function from gene expressions and ontologies.

We introduce a methodology for inducing predictive rule models for functional classification of gene expressions from microarray hybridisation experiments. The basic learning method is the rough set framework for rule induction. The methodology is different from the commonly used unsupervised clustering approaches in that it exploits background knowledge of gene function in a supervised manner. Genes are annotated using Ashburner's Gene Ontology and the functional classes used for learning are mined from these annotations. From the original expression data, we extract a set of biologically meaningful features that are used for learning. A rule model is induced from the data described in terms of these features. Its predictive quality is fine-turned via cross-validation on subsets of the known genes prior to classification of unknown genes. The predictive and descriptive quality of such a rule model is demonstrated on the fibroblast serum response data previously analysed by Iyer et. al. Our analysis shows that the rules are capable of representing the complex relationship between gene expressions and function, and that it is possible to put forward high quality hypotheses about the function of unknown genes.

Algorithms↗

Effect of somatostatin and octreotide on proliferation and vascular endothelial growth factor secretion from murine endothelial cell line (HECa10) culture.

Angiogenesis, development of new blood vessels, is required for normal tissue repair and also for tumor cell proliferation, extracellular matrix invasion, and hematogenous metastases. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that has been shown to play a key role in neovascularization. Inhibition of angiogenesis in vitro and in vivo was documented by administration of native neuropeptide somatostatin and its analog octreotide. We have studied the effect of somatostatin-14 (SRIF) and ocreotide (sandostatin) on proliferation activity and VEGF release from cultured murine endothelial cells HECa10 in vitro. SRIF in concentrations from 10(-9) to 10(-5) M and ocreotide in concentrations from 10(-9) to 10(-5) M diminished the proliferative activity of cultured cells vs controls. SRIF and ocreotide in concentrations from 10(-14) to 10(-6) M did not change the release of VEGF into supernatants of 24 or 72 h endothelial cell cultures. Although we showed the antiproliferative effect of SRIF and ocreotide on mouse endothelial cells, we were unable to demonstrate the inhibitory effect of tested peptides on VEGF secretion in vitro.

Animals↗

Pituitary-adrenocortical responses to the chronic administration of granulocyte colony-stimulating factor in rats.

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor, but it may play a role in the regulation of the neuroendocrine system activity. Only few data are available about its possible influence on the pituitary gland. We have recently reported an acute stimulatory effect of G-CSF (and of GM-CSF) on adrenocorticotropic hormone (ACTH) secretion in rats in vivo. The purpose of the present study was to evaluate whether chronic administration of G-CSF affects ACTH and corticosterone secretion and growth processes of the rat anterior pituitary gland and adrenal cortex in vivo. We have demonstrated that G-CSF (at a dose of 10.0 microg/kg body weight (BW)) injected s.c. once daily (for 7 days), stimulated both ACTH and corticosterone secretion. Simultaneously, G-CSF treatment did not change the total anterior pituitary cell proliferation as revealed by immunohistochemical staining of proliferating cell nuclear antigen (PCNA). On the other hand, proliferative activity of corticotrophs, detected in the sections of the anterior pituitary using double-labeling. was significantly increased after treatment with G-CSF. Moreover, this growth factor induced an increase in the proliferation ratio in the entire adrenal equatorial section. These findings suggest an involvement of G-CSF in the regulation of pituitary-adrenal axis and support the hypothesis of bidirectional associations between the immune system and the endocrine glands.

Adrenal Cortex↗

Effects of Gn-RH, TRH, and CRF administration on plasma leptin levels in lean and obese women.

Leptin, a hormone which is produced by adipose tissue, has been shown to inhibit food intake, increase energy expenditure and influence the function of hypothalamo-pituitary-gonadal, -thyroid, and -adrenal systems. We have examined the association between leptin concentrations (RIA method) and levels of different hormones using standard Gn-RH, TRH and CRF tests (at 0, 30, 60, and 120 min) in regularly menstruating 10 lean and 10 obese premenopausal women in follicular phase. FSH, LH, estradiol (E2) and progesterone (P) concentrations in Gn-RH test; TSH, PRL, fT3, fT4 in TRH test; ACTH, DHEA-S, cortisol in CRF test were measured by RIA, ELISA or IRMA methods. The obese subjects had thicker four skinfolds, higher fat content in the body, and bigger BMI, compared to the lean females. Gn-RH test: We have noted higher basal leptin values in obese women than in lean subjects, which was stable during the Gn-RH test. In the same blood specimen, basal insulin concentrations did not differ between the tested groups of patients. There were no correlations between E(2), P, or gonadotropins and plasma leptin concentrations between both groups of patients. We have revealed the negative correlation between LH mobilization (maximal incremental values over basal levels; Delta%) and baseline leptin concentrations in all observed subjects. TRH test: In both groups of patients the leptin levels decreased at 120 min of TRH administration. We have noted diminished PRL and TSH mobilisation in obese subjects in comparison to the controls. In all females (n = 20) the correlations between TSH or PRL mobilization and BMI, skinfold thickness and the mass of body fat in kg were negative. In obese subjects only we observed the positive correlations between fT(3)concentrations at 60 and 120 min of the test or Delta% of fT(3)and leptin levels. CRF test: In obese females, we noted higher basal ACTH and cortisol concentrations with decreased mobilization (Delta%) of ACTH or cortisol, as compared to the controls. Basal leptin values were also higher in obese women comparing controls and did not significantly change within 2 h after CRF injection. In all the observed subjects (n = 20), we noted positive correlations between baseline values of leptin and ACTH, as well as negative correlation between basal concentrations of leptin and mobilisation of cortisol. The obtained results show that the hypothalamic neuropeptides may influence leptin secretion in humans.

Adipose Tissue↗

Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and soluble interleukin-2 receptor (sIL-2R) concentrations in peripheral blood as markers of pituitary tumours.

Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and soluble interleukin-2 receptor (sIL-2R) are important cytokines. They are secreted by normal pituitary glands and those with all types of adenomas and may be involved in pituitary tissue growth. The peripheral blood concentrations of VEGF, bFGF and sIL-2R in nineteen patients (17-70 years) with pituitary tumours and ten healthy subjects (23-34 years) were studied. Hypersecretion of prolactin (five cases), human growth hormone (four cases), and thyroid stimulating hormone (one case) was recorded in some patients, and the remaining subjects were diagnosed as having nonfunctional pituitary tumours. Increased peripheral blood plasma levels of VEGF (310.82 +/- 59.17 pg/ml) compared with controls (40.32 +/- 11.80 pg/ml; p < 0.01), as well as bFGF (87.27 +/- 7.58 pg/ml) versus controls (11.14 +/- 2.43 pg/ml; p < 0.001) were recorded. The levels of sIL-2R did not differ between the pituitary tumour patients (4,490.58 +/- 581.50 pg/ml) and control subjects (3,617.01 +/- 1,397.18 pg/ml; p > 0.05). The concentrations of VEGF and bFGF in the peripheral blood are useful additional markers of the presence of tumours.

Adolescent↗

Modelling prognostic power of cardiac tests using rough sets.

Rough sets (Pawlak Z. Rough Sets: Theoretical Aspects of Reasoning about Data, Dordrecht: Kluwer Academic Publishers, 1991) is a relatively new approach to representing and reasoning with incomplete and uncertain knowledge. This article introduces the basic concepts of rough sets and Boolean reasoning (Brown FM. Boolean Reasoning: The Logic of Boolean Equations, Dordrecht: Kluwer Academic Publishers, 1990). A rough set framework is then set up to investigate the prognosis of cardiac events in a set of patients with chest pain that was earlier studied by Geleijnse et al. (J Am Coll Cardiol 1996;28(2):447-454). That study used logistic regression to find that the single most important independent predictor for future hard cardiac events (cardiac death or non-fatal myocardial infarction) was an abnormal scintigraphic scan pattern. However, performing a scintigraphic scan is a relatively expensive procedure, and may for some patients not really be fully necessary as knowledge of the outcome of the scan may be redundant with respect to making a prognosis. Using an approach based on rough sets, this paper explores how a patient group in need of a scintigraphic scan can be identified for subsequent modelling. Identification of such patients may potentially contribute to lowering the cost of medical care and to improving its quality since, virtually without loss of information, fewer patients may be referred for this procedure.

Adolescent↗