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41.

Objective

The aim of this study was to determine whether leptin, a member of the adipocytokines involved in immune and inflammatory response regulation, may influence some aspects of mast cell biology.

Materials and methods

Experiments were done in vitro on fully mature tissue rat mast cells isolated from the peritoneal cavity, and leptin was used at concentrations 0.001–100 ng/ml. The effect of leptin on mast cell degranulation (histamine release assay), intracellular Ca2+ level (fluorimetry), pro-inflammatory mediator release (ELISA technique), surface receptor expression (flow cytometry and confocal microscopy), and migration (Boyden microchamber assay) was estimated.

Results

Leptin was found to stimulate mast cells to degranulation and histamine release. It induced the intracellular Ca2+ increase, as well. In response to leptin stimulation, mast cells generated and released cysLTs and chemokine CCL3. Leptin-induced upregulation of CYSLTR1 and CYSLTR2 surface expression was observed. Moreover, this adipocytokine stimulated mast cells to migratory response, even in the absence of extracellular matrix (ECM) proteins.

Conclusions

Our observations clearly documented that leptin promotes the pro-inflammatory activity of mast cells, and it thereby engages these cells in the inflammatory processes.
  相似文献   
42.
IgA nephropathy (IgAN) is recognized as most frequent form of primary glomerulonephritis worldwide. IgAN is associated with renal degradation occurring due to irreversible pathological changes leading to glomerulosclerosis and interstitial fibrosis. It remains poorly understood whether and to what extent these changes are followed by the activation of regenerative mechanisms. Therefore, in this study we aimed to evaluate regenerative potential of IgAN patients by quantitating the frequencies of several stem cell types, namely circulating very small embryonic-like stem cells (VSELs), hematopoietic stem cells (HSCs), endothelial progenitor cells (EPCs) as well as different monocyte subsets with varying maturation and angiopoietic potential. Moreover, we analyzed whether changes in stem cell and monocyte frequencies were related to alterations of several chemotactic factors (stromal derived-factor (SDF-1), angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2)) and a marker of monocyte/macrophage activation, namely soluble form of CD163 receptor (sCD163). We showed that IgAN patients presented with enhanced levels of VSELs, but not other stem cell types. We also demonstrated significantly elevated numbers of intermediate monocytes known for their M2-like properties as well as high angiopoietic potential and CD163 expression. This finding was accompanied by detection of elevated sCD163 plasma levels in IgAN patients. Taking together, we demonstrated here that IgAN is associated with selective mobilization of VSELs and increased maturation of monocytes towards M2-like and angiopoietic phenotype. These findings contribute to better understanding of the role of regenerative mechanisms in the pathogenesis of chronic inflammation in the course of IgAN.  相似文献   
43.
In this report, the authors examined the characteristic features of morphology and molecular biology of Ki‐67, p53, Bcl‐2, and cyclooxygenase‐2 (Cox‐2) immunocytochemistry in low‐grade endometrioid endometrial carcinoma (LG‐ENEC) and disordered proliferative (DP)/benign hyperplastic (BH) endometrium. We carried out a prospective study by collecting endometrial imprints from freshly resected uteri over a 20‐month period and finally 104 patients were evaluated with endometrial cytology. We focused on LG‐ENECs, as well as on BH endometrium and its precursor lesion, DP endometrium, firstly because of the overlapping cytomorphology of these pathologic entities and secondly because of the lack of agreement in the differential diagnosis of atypical hyperplasia from complex hyperplasia and well‐differentiated endometrial carcinoma, even in curettage specimens. Ki‐67 expression of LG‐ENEC showed predominance in comparison with DP/BH endometrium. Furthermore, high levels of Bcl‐2 (>50%) were expressed only in DP/BH endometrium. DP/BH endometrium was negative for p53 marker, except from two cases of BH endometrium. Cox‐2 expression ≥50% was found only in LG‐ENECs. Using Ki‐67, Bcl‐2, p53, and Cox‐2 markers, we managed to distinguish fully DP/BH endometrium from LG‐ENEC. Higher Ki‐67%/Bcl‐2% rate and also higher Cox‐2 expression were found in LG‐ENEC cases with FIGO stage ≥ IC, than in cases with FIGO stage < IC. The immunocytochemical findings from a combination of Ki‐67, p53, Bcl‐2, and Cox‐2, may differentiate LG‐ENEC from DP/BH endometrium with overlapping cytomorphology. Immunocytochemistry appeared to be useful also for the correlation between LG‐ENEC and FIGO stage. Diagn. Cytopathol. 2014;42: 134–142. © 2013 Wiley Periodicals, Inc.  相似文献   
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45.
Programmed death-1 (PD-1) is one of the most important inhibitory co-receptors expressed predominantly on activated T and B lymphocytes whose expression could be sustained by permanent antigenic stimulation accompanying chronic or recurrent tonsillitis. The expression of PD-1 and PD-1L was analyzed using flow cytometry on hypertrophied tonsils collected from 57 children. We observed high expression of PD-1 and PD-1L on certain lymphocytes subpopulations of hypertrophied tonsils; among T cells, the expression of PD-1 on protein level was higher on CD4+ cells (70.3 %) than on CD8+ cells (35 %). Interestingly, a limited expression of PD-1 was observed on CD19+ B lymphocytes (6.5 %), while CD5+CD19+ B cells overexpressed PD-1 (52.5 %). Moreover, the expression of PD-1L was also higher on CD5+CD19+ B cells (16.5 %) than on CD19+ B cells (3.5 %) and on CD4+ T cells (20 %) than on CD8+ T cells (10 %). PD-1 and PD-1L expressions correlated only on CD5+CD19+ cells. In conclusion, high expression of PD-1 and PD-1L on T and B cells could represent hallmark of immune system adaptation to chronic antigenic exposition in patients with tonsillitis.  相似文献   
46.
The purpose of this randomized, prospective study was to identify factors influencing the psychological distress of breast cancer patients and their husbands during remission. Background variables and distress levels of 172 couples in two locations (Graz, Austria, and Jerusalem, Israel) were assessed by using three standardized instruments in two interviews conducted 6-8 months apart. In both geographic-cultural groups, women whose partners refused to participate in the interview reported significantly less perceived family support. The global severity index (measuring total psychological distress) reflected minor changes in psychological distress of both patients and their husbands over time.  相似文献   
47.
Chromatin immunoprecipitation identifies specific interactions between genomic DNA and proteins, advancing our understanding of gene-level and chromosome-level regulation. Based on chromatin immunoprecipitation experiments using validated antibodies, we define the genome-wide distributions of 19 histone modifications, one histone variant, and eight chromatin-associated proteins in Caenorhabditis elegans embryos and L3 larvae. Cluster analysis identified five groups of chromatin marks with shared features: Two groups correlate with gene repression, two with gene activation, and one with the X chromosome. The X chromosome displays numerous unique properties, including enrichment of monomethylated H4K20 and H3K27, which correlate with the different repressive mechanisms that operate in somatic tissues and germ cells, respectively. The data also revealed striking differences in chromatin composition between the autosomes and between chromosome arms and centers. Chromosomes I and III are globally enriched for marks of active genes, consistent with containing more highly expressed genes, compared to chromosomes II, IV, and especially V. Consistent with the absence of cytological heterochromatin and the holocentric nature of C. elegans chromosomes, markers of heterochromatin such as H3K9 methylation are not concentrated at a single region on each chromosome. Instead, H3K9 methylation is enriched on chromosome arms, coincident with zones of elevated meiotic recombination. Active genes in chromosome arms and centers have very similar histone mark distributions, suggesting that active domains in the arms are interspersed with heterochromatin-like structure. These data, which confirm and extend previous studies, allow for in-depth analysis of the organization and deployment of the C. elegans genome during development.  相似文献   
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49.
Suppressed immune status facilitates immune escape mechanisms that allow chronic lymphocytic leukemia cells to proliferate and expand. The expression of HLA-G could effectively inhibit the immune response. In immune response inhibitory signals follow activation of immune system which might be occur during bacterial or viral infection in CLL patients. In the current study we characterized two components of immune system, inhibitory molecule HLA-G with its receptor – CD85j and Toll-like receptor 9.  相似文献   
50.
Over 260,000 (2013) new oral squamous cell carcinoma (OSCC) cases are reported annually worldwide. Despite development in OSCC management, the outcome is still unsatisfactory. Identification of new molecular markers may be of use in prevention, prognosis, and choice of an appropriate therapy. The intracellular molecular signalling pathway of phosphatidyl-inositol-3-kinase is involved in the process of cell growth, differentiation, migration, and survival. The main components of this pathway: PIK3CA (phosphatidylinositol-4,5-bisphosphate-3-kinase catalytic subunit α), PTEN (phosphatase and tensin homologue deleted on chromosome 10), and AKT (serine-threonine kinase) are potential objects of research when introducing new therapeutic agents. The aim of this paper is to evaluate the PIK3CA, PTEN, and AKT gene mutations as prognostic factors in OSCC and to describe their role in aggressive disease progression. This is crucial for oral cancer biology understanding and for indicating which direction new clinical treatments should take.  相似文献   
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