Search results for "L2"
showing 10 items of 413 documents
Temperature and time dependent electron trapping in Al2O3 thin films onto AlGaN/GaN heterostructures
2022
In this article, the charge trapping phenomena in Al2O3 thin films grown by atomic layer deposition (ALD) on AlGaN/GaN heterostructures have been studied by time-dependent capacitance–voltage (C-V) measurements as a function of temperature. In particular, monitoring the transient of the capacitance enabled us to estimate the maximum depth of the insulating layer interested by the negative charge trapping effect under our bias stress conditions and to determine a charge traps density in the bulk Al2O3 in the order of 3 × 1019 cm−3. A temperature dependent C-V analysis up to 150 °C demonstrated the presence of two competitive mechanisms that rule the electron capture and emission in the Al2O3…
Toll-like receptor 3 mediates expression of clusterin/apolipoprotein J in vascular smooth muscle cells stimulated with RNA released from necrotic cel…
2010
Clusterin/Apolipoprotein J is a protein that is upregulated in a broad spectrum of diverse pathological processes. The predominant form is a secreted glycoprotein (sCLU) with cytoprotective and anti-inflammatory properties which shows enhanced expression in vascular smooth muscle cells (VSMC) following aortic injury and in atherosclerotic disease. Recent evidence indicates that during atherosclerosis, Toll-like receptors (TLRs) are activated in vascular cells by endogenous ligands. Here, we analyzed whether CLU expression in VSMC is controlled by TLRs, and stimulated by factors associated with or released by necrotic cells. Activation of TLR3 by the synthetic RNA analogue polyinosinic-polyc…
mRNA-induction and cytokine release during in vitro exposure of human nasal respiratory epithelia to methyl methacrylate
2007
Abstract Background Methyl methacrylate (MMA) has been reported to cause histopathological changes in rodent nasal epithelium after inhalation challenges. Data in humans are lacking. Methods In this in vitro design 22 primary cell cultures taken from inferior turbinate tissue of healthy individuals were exposed to MMA concentrations of 50 ppm (German MAK-value) and 200 ppm. mRNA expression and cytokine release of inflammatory mediators were quantified after 4 h and after 24 h. Controls were exposed to synthetic air. Q-PCR analysis was performed for TNF-α, IL-1β, IL-6, IL-8, MCP-1, GMCSF, Cox-1 and Cox-2. ELISA assays were performed from culture supernatants for TNF-α, IL-1β, IL-6, IL-8, MCP…
Self-adjuvanting C18 lipid vinil sulfone-PP2A vaccine: study of the induced immunomodulation against
2017
Despite the importance of the adjuvant in the immunization process, very few adjuvants merge with the antigens in vaccines. A synthetic self-adjuvant oleic-vinyl sulfone (OVS) linked to the catalytic region of recombinant serine/threonine phosphatase 2A from the nematode Angiostrongylus costaricensis (rPP2A) was used for intranasal immunization in mice previously infected with Trichuris muris. The animal intranasal immunization with rPP2A-OVS showed a reduction of 99.01% in the number of the nematode eggs and 97.90% in adult. The immunohistochemical analysis of the intestinal sections showed that in immunized animals with lipopeptide the mucus was significantly higher than in the other expe…
Influenza A virus infection inhibits the efficient recruitment of Th2 cells into the airways and the development of airway eosinophilia.
2003
Abstract Most infections with respiratory viruses induce Th1 responses characterized by the generation of Th1 and CD8+ T cells secreting IFN-γ, which in turn have been shown to inhibit the development of Th2 cells. Therefore, it could be expected that respiratory viral infections mediate protection against asthma. However, the opposite seems to be true, because viral infections are often associated with the exacerbation of asthma. For this reason, we investigated what effect an influenza A (flu) virus infection has on the development of asthma. We found that flu infection 1, 3, 6, or 9 wk before allergen airway challenge resulted in a strong suppression of allergen-induced airway eosinophil…
An Alternative Pathway of Imiquimod-Induced Psoriasis-Like Skin Inflammation in the Absence of Interleukin-17 Receptor A Signaling
2013
Topical application of imiquimod (IMQ) on the skin of mice induces inflammation with common features found in psoriatic skin. Recently, it was postulated that IL-17 has an important role both in psoriasis and in the IMQ model. To further investigate the impact of IL-17RA signaling in psoriasis, we generated IL-17 receptor A (IL-17RA)-deficient mice (IL-17RA(del)) and challenged these mice with IMQ. Interestingly, the disease was only partially reduced and delayed but not abolished when compared with controls. In the absence of IL-17RA, we found persisting signs of inflammation such as neutrophil and macrophage infiltration within the skin. Surprisingly, already in the naive state, the skin …
CCL27 Signaling in the Tumor Microenvironment
2021
Chemokines are a group of small proteins which play an important role in leukocyte migration and invasion. They are also involved in the cellular proliferation and migration of tumor cells.Chemokine CCL27 (cutaneous T cell-attracting chemokine, CTACK) is mainly expressed by keratinocytes of the normal epidermis. It is well known that this chemokine plays an important role in several inflammatory diseases of the skin, such as atopic dermatitis, contact dermatitis, and psoriasis. Moreover, several studies have shown an association between CCL27 expression and a variety of neoplasms including skin cancer.In this chapter, we address the role of chemokine CCL27 in the tumor microenvironment in t…
The fungal lactone oxacyclododecindione is a potential new therapeutic substance in the treatment of lupus-associated kidney disease.
2013
Recently oxacyclododecindione (Oxa), a macrocyclic lactone isolated from the imperfect fungus Exserohilum rostratum, has been described as a potent transcription inhibitor of inducible proinflammatory and profibrotic genes in cell culture models. As kidney disease in systemic lupus erythematosus is characterized by aberrant expression of inflammatory mediators and infiltration of immune cells, we investigated the effect of Oxa in MRL-Fas(lpr) mice, a model of systemic lupus erythematosus. These mice develop a spontaneous T-cell and macrophage-dependent autoimmune disease including severe glomerulonephritis that shares features with human lupus. Comparable to the results of in vitro models, …
Hypothermic preservation of lung allograft inhibits cytokine-induced chemoattractant-1, endothelial leucocyte adhesion molecule, vascular cell adhesi…
2007
Summary Organ dysfunction is a major clinical problem after lung transplantation. Prolonged cold ischaemia and reperfusion injury are believed to play a central role in this complication. The influence of cold preservation on subsequent warm reperfusion was studied in an isolated, ventilated and perfused rat lung. Rat lungs were flushed with cold Perfadex-solution and stored at 4°C for different time periods. Thereafter lungs were perfused and ventilated for up to 3 h. Physiological parameters, production of inflammatory mediators and leucocyte infiltration were measured before and after perfusion. Lungs subjected to a cold ischaemia time of up to 6 h showed stable physiological conditions …
Tick saliva increases production of three chemokines including monocyte chemoattractant protein-1, a histamine-releasing cytokine
2014
Summary The effect of Ixodes ricinus tick saliva on the production of various cytokines and chemokines by mouse splenocytes was tested by a cytokine array. We demonstrated a strong upregulation of three chemokines, monocyte chemoattractant protein-1 (MCP-1), thymus-derived chemotactic agent 3 (TCA-3) and macrophage inflammatory protein 2 (MIP-2). MCP-1 could be induced by tick saliva itself. While TCA-3 and MIP-2 are engaged in Th2 polarization of the host immune response associated with tick feeding, MCP-1 may act as a histamine release factor, increasing blood flow into the feeding lesion thus facilitating tick engorgement in the late, rapid feeding phase.