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Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
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The aim of the study was the investigation of the biochemical condition of elements likely to directly participate in active closing of the urethral lumen. We estimated glycogenolysis in urinary bladder, perivesical connective tissue and levator ani muscle (LAM) samples obtained intraoperatively from 80 stress incontinent women. Glycogen content as well as activities of active and total glycogen phosphorylase and acid exo-1,4-alpha-glucosidase were measured. Material from the urinary bladder and perivesical connective tissue was insignificantly altered, and glycogen contents in the bladder (2.03±1.38 g/100 g wet tissue) were considered to be normal. In the LAM glycogenolysis was much more activated than in other tissues (p<0.001 by Fischer's exact test). Of LAM specimens 78% (22/28) revealed imbalanced biochemistry of glycogen with activation of hydrolytic decomposition. We conclude that stress urinary incontinence in women is frequently associated with metabolic alterations in the periurethral striated fibres. This study indirectly supports our recent hypothesis on the pathogenesis of the disease in terms of muscle fibre type transitions.  相似文献   
5.
The purpose of the present paper was to demonstrate the antitumor activity of lymphocytes and antibodies in the antibody-dependent cell-mediated cytotoxicity test (ADCC) in relation to the tumor growth in adult and aging rats bearing a methylcholanthrene-induced sarcoma (MC-Sa). In the syngeneic system using the ADCC test effector spleen lymphocytes, 51Cr labeled MC-Sa target cells and anti-MC-Sa serum were derived from inbred male Wistar rats. It was found that adult and aging tumor-bearing rats possessed lymphocytes (LSa) and antibodies (Ab) which were active in ADCC. In comparative studies between the groups of adult and aging rats a reverse relationship between tumor growth and activity of LSa and Ab in the ADCC test has been found. Thus, the larger weight of tumors in the group of adult rats was followed by lower LSa and Ab activities in the ADCC test. On the other hand, the smaller tumor growth in the group of aging rats was followed by higher activities of LSa and Ab in this test. We suggest that the ADCC phenomenon could be one of the antitumor mechanisms especially effective in aging rats.  相似文献   
6.
A prospective, randomized trial evaluates the effects of two postoperative treatment regimens on survival in 198 adult patients with supratentorial gliomas. All patients were irradiated with 6 000 rads after possibly radical removal of tumors. CCNU administration in the dosis of 100 mg/sq m of body surface every 6–8 weeks following surgery proved to have no significant effect on the survival of patients. The median survival time in patients receiving radiation therapy alone was 61±7 weeks, while in those receiving additional chemotherapy was 56±4 weeks. Tumor histological malignancy and patients age were found to be the only important prognostic factors, irrespective of the treatment modality. Address for offprints: T Trojanowski, Department of Neurosurgery, Medical School, Jaczewskiego 8, 20-950 Lublin, Poland  相似文献   
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In the presented studies HBcAg-specific cytokine production (IFN-gamma, IL-2, IL-4, IL-5 and IL-10) was evaluated, by Th lymphocytes isolated from peripheral blood of children with acute or chronic B hepatitis. Moreover, effect of IL-10 neutralization was examined on HBcAg-induced secretory response of Th lymphocytes obtained from children with chronic B hepatitis. The studies were performed on 12 children with acute self-limited B hepatitis and 20 children with chronic active B hepatitis. CD4 T cells were isolated from peripheral blood of the patients, cultured for 48h in presence of rHBcAg or in its absence (control). Production of studied cytokines was monitored using ELISPOT and ELISE assays. The course of acute self-limited B hepatitis was associated with preferential Th1-type response, manifested by elevated production of IFN-gamma and IL-2. On the other hand, in chronic B hepatitis a diminished response to HBcAg of both Th1 and Th2 types was disclosed, characterized by very low secretion of IFN-gamma, IL-2, IL-4 and IL-5. In parallel, preferential antigen-specific production of IL-10 was noted and its suppressive effect on HBcAg-induced response of Th1 cells. The results permitted to conclude that in children with acute self-limited B hepatitis preferential HBcAg-specific activation of Th1 lymphocytes may be of significance for efficient anti-HBV immune response. On the other hand, development of chronic B infection in children seems to be determined by disturbed HBcAg-specific functions of both Th1 and Th2 cells whereas activity of the disease may be controlled by anti-inflammatory response of antigen-presenting cells and/or of regulatory CD4 T lymphocytes, involving IL-10 production.  相似文献   
9.
The mesenteric and pulmonary mast cells of guinea pigs were obtained by enzymatic dispersion of the tissues with the enzyme collagenase. The guinea pig mast cells obtained by this method were morphologically intact, as judged by light microscopy. The mast cells from lung and mesentery of actively sensitized guinea pigs released histamine in a dose-dependent fashion after challenge with specific antigen. Both pulmonary and mesenteric mast cells of nonsensitized animals were unresponsive to the action of compound 48/80 and concanavalin A. Both populations of mast cells responded to polymyxin B, but the magnitude of histamine release was low. These cells responded strongly to the ionophore A23187; the mesenteric mast cells were markedly more reactive than pulmonary mast cells.  相似文献   
10.
Allergic angiitis and granulomatosis (Churg-Strauss syndrome) is one of the rare form of idiopathic (primary) vasculitis. It is characterized by asthma, blood hypereosinophilia and typical microscopic features: nectrotizing vasculitis, tissue infiltration by eosinophils and extravasal granulomas. We present an autopsy case of 55-years old man with Churg-Strauss syndrome complicated by eosinophilic myocarditis.  相似文献   
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