Search results for " ACTIVATION"
showing 10 items of 1535 documents
Prevalence and prognostic implications of active cytomegalovirus infection in patients with acute heart failure
2010
AHF (acute heart failure) causes significant morbidity and mortality. Recent studies have postulated that the expression of inflammatory mediators, such as cytokines and chemokines, plays an important role in the development and progression of heart failure. A pro-inflammatory state has been postulated as a key factor in triggering CMV (cytomegalovirus) reactivation. Therefore we sought to determine the prevalence of active CMV infection in immunocompetent patients admitted for AHF and to quantify the association with the risk of the combined end point of death or AHF readmission. A total of 132 consecutive patients admitted for AHF were enrolled in the present study. Plasma CMV DNAaemia wa…
Effect of soluble guanylyl cyclase activator and stimulator therapy on nitroglycerin-induced nitrate tolerance in rats
2015
Chronic nitroglycerin (GTN) anti-ischemic therapy induces side effects such as nitrate tolerance and endothelial dysfunction. Both phenomena could be based on a desensitization/oxidation of the soluble guanylyl cyclase (sGC). Therefore, the present study aims at investigating the effects of the therapy with the sGC activator BAY 60-2770 and the sGC stimulator BAY 41-8543 on side effects induced by chronic nitroglycerin treatment. Male Wistar rats were treated with nitroglycerin (100mg/kg/d for 3.5days, s.c. in ethanol) and BAY 60-2770 (0.5 or 2.5mg/kg/d) or BAY 41-8543 (1 and 5mg/kg/d) for 6days. Therapy with BAY 60-2770 but not with BAY 41-8543 improved nitroglycerin-triggered endothelial …
Reciprocal stimulation of gammadelta T cells and dendritic cells during the anti-mycobacterial immune response.
2004
Gammadelta T cells and dendritic cells (DC) are two distinct cell types of innate immunity that participate in early phases of immune response against Mycobacterium tuberculosis infection. Here we show that a close functional relationship exists between these cell populations. Using an in vitro coculture system, Vgamma1 T cells from Tcrb(-/- )mice were found to be activated by DC infected in vitro with BCG, as indicated by the elevated CD69 expression, IFN-gamma secretion and cytotoxic activity. This activation process was due to a non-cognate mechanism since it required neither cell to cell contact nor interaction between the TCR and a specific antigen, but was mediated by DC-derived IL-12…
Diminished Contact Hypersensitivity Response in IL‐4 Deficient Mice at a Late Phase of the Elicitation Reaction
1997
Contact hypersensitivity (CHS) is thought to depend on the activation of T cells of Th1 and/or Tc1 type. The role of Th2/Tc2 cells in the contact allergic reaction is not clear. The aim of this study was to analyse the functional contribution of Th2/Tc2 cells in CHS using the interleukin-4 (IL-4) deficient mouse model. Interleukin-4 deficient (IL4T) and control (wt) mice were sensitized by epicutaneous application of 2,4-dinitrofluorobenzene. The ear swelling response measured 24 h after challenge was similar in IL4T and control mice. However, from 48 h onwards, ear swelling values were significantly reduced in IL4T mice. The stimulatory capacity of freshly isolated as well as 3-day culture…
In vitro anticholinergic drugs affect CD8+ peripheral blood T-cells apoptosis in COPD
2011
Novel pharmacological strategies are aimed at the resolution of systemic inflammation in COPD potentiating peripheral blood T-cell (PBT-cell) apoptosis. Although muscarinic acetylcholine receptors (mAChRs) M(3) and choline-acetyltransferase (ChAT) participate in the airway inflammation of COPD, their role in PBT-cell apoptosis remains unexplained. We evaluated in PBT-cells from COPD patients, smoker (S) and control (C) subjects: (1) apoptosis (by annexin V binding), (2) mAChR M(3) and ChAT expression, acetylcholine (ACh)-binding; (3) choline levels in serum and PBT-cells extracts. We tested the effects of Tiotropium (Spiriva(®)) and hemicholinium-3 (HCh-3) on apoptosis, NFκB pathway, caspas…
Polymorphonuclear leukocyte integrins in chronic renal failure
2005
Patients with chronic renal failure (CRF), in comparison with general population, show a higher cardiovascular mortality, not fully explained by the "traditional" risk factors. Among the new factors that have been hypothesized, leukocytes might play an important role. In a group of patients with mild CRF we determined, at baseline and after in vitro activation with 4-phorbol-12-myristate-13-acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (fMLP), the polymorphonuclear leukocytes (PMN) beta2-integrin pattern (CD11a, CD11b, CD11c and CD18) by using indirect immunofluorescence with a flow cytometer. At baseline we observed an increase in the phenotypical expression of CD11b, CD11c and…
The effect of cyclosporin A, FK506 and rapamycin on the murine contact sensitivity reaction
1998
We have evaluated the effects of three potent immunosuppressive agents, cyclosporin A (CsA), FK506 and rapamycin, on the murine contact sensitivity (CS) reaction to the hapten trinitrochlorobenzene. Development of CS reaction requires participation of three distinct T cell subsets: alphabeta+, CD4+ T lymphocytes, which are the classical effector cell of the CS reaction, gammadelta+ T lymphocytes, and alphabeta+, double-negative (CD4- CD8-) T lymphocytes that express the B220 molecule and produce IL-4. We found that all three drugs inhibit the development of the CS reaction, but they affect different target cells. In fact, rapamycin and FK-506 block both alphabeta+, CD4+ and gammadelta+ T ly…
Conditions for the Enhancing Effect of Protease Inhibitors on the Concanavalin A Induced Thymidine Response of Murine Lymphocytes
1983
Incorporation of [<sup>3</sup>H]-thymidine – [<sup>3</sup>H]-TdR – into concanavalin A (Con A) stimulated murine splenocytes and thymocytes was found to be enhanced by addition of certain concentrations of phenyl-methyl-sulfonylfluoride (PMSF), di-isopropylfluorophosphate (DFP), N-α-tosyl-<i>L</i>-lysyl-<i>L</i>-chloromethylketone (TLCK), and soybean trypsin inhibitor (SBTI). No enhancement could be observed when mononuclear cells of the peripheral blood were used, and a medium enhancement when thymocytes were applied. Furthermore, no enhancing effect of the protease inhibitors (PI) on the Con A response of murine splenocytes could be observed…
Pentoxifylline Prevents Loss of PP2A Phosphatase Activity and Recruitment of Histone Acetyltransferases to Proinflammatory Genes in Acute Pancreatitis
2009
Mitogen-activated protein kinases (MAPKs) are considered major signal transducers early during the development of acute pancreatitis. Pentoxifylline is a phosphodiesterase inhibitor with marked anti-inflammatory properties through blockade of extracellular signal regulated kinase (ERK) phosphorylation and tumor necrosis factor alpha production. Our aim was to elucidate the mechanism of action of pentoxifylline as an anti-inflammatory agent in acute pancreatitis. Necrotizing pancreatitis induced by taurocholate in rats and taurocholate-treated AR42J acinar cells were studied. Phosphorylation of ERK and ERK kinase (MEK1/2), as well as PP2A, PP2B, and PP2C serine/threonine phosphatase activiti…
Inactivation of glycogen synthase kinase-3β protects against kainic acid-induced neurotoxicity in vivo
2004
Many neurodegenerative diseases involve oxidative stress and excitotoxic cell death. In an attempt to further elucidate the signal transduction pathways involved in the cell death/cell survival associated with excitotoxicity, we have used an in vivo model of excitotoxicity employing kainic acid (KA)-induced neurotoxicity. Here, we show that extracellular signal-related kinase (ERK) 2, but not ERK 1, is phosphorylated and thereby activated in the hippocampus and cerebellum of kainic acid-treated mice. Phosphorylation and hence inactivation of glycogen synthase kinase 3beta (GSK-3beta), a general survival factor, is often a downstream consequence of mitogen-activated protein kinase pathway ac…