Search results for " ACTIVATION"
showing 10 items of 1535 documents
Liver X Receptor ligand cytotoxicity in colon cancer cells and not in normal colon epithelial cells depends on LXRβ subcellular localization
2015
Increasing evidence indicates that Liver X Receptors (LXRs) have some anticancer properties. We recently demonstrated that LXR ligands induce colon cancer cell pyroptosis through an LXRβ-dependent pathway. In the present study, we showed that human colon cancer cell lines presented differential cytoplasmic localizations of LXRβ. This localization correlated with caspase-1 activation and cell death induction under treatment with LXR ligand. The association of LXRβ with the truncated form of RXRα (t-RXRα) was responsible for the sequestration of LXRβ in the cytoplasm in colon cancer cells. Moreover t-RXRα was not expressed in normal colon epithelial cells. These cells presented a predominantl…
Contact sensitivity as a model for T-cell activation in skin.
1995
Contact sensitivity has served as a useful model for the primary activation of T cells in skin and skin-associated lymphoid tissue. We have been interested in the early signals necessary for the induction of an allergen-specific T-cell response, as well as the factors controlling the intensity and extent of such an immune reaction. Because cytokines qualified as possible candidate molecules involved in directing primary immune responses in skin, we studied the early changes in the cytokine pattern of the epidermis. Apart from defining a cytokine pattern specifically induced only after application of allergen, we also identified Langerhans-cell-derived interleukin (IL)-1β as the first cytoki…
Effects of pyrolysis conditions on the porous structure development of date pits activated carbon
2012
International audience; Activated carbons were prepared from biomass of Algerian date pits for developing efficient and cheap adsorbents in the aim to remove heavy metals from waste water. Carbon adsorbents were obtained following two successive treatments: pyrolysis under dry nitrogen flow and physical activation under wet nitrogen flow. Pyrolysis process was optimized by varying some operating parameters such as temperature, nitrogen flow, heating rate and pyrolysis hold time in order to determine their effects on the porous structure development of date pits activated carbon. Chars obtained from pyrolysis process were activated with the same operating conditions (activation temperature o…
Elemental composition of sediments from a former silver mine in Freiberg/East Germany
1999
Abstract We have determined the contents of 48 elements in 11 representative sediments from a former Ag-mine in Freiberg/Sachsen. As analytical method the instrumental neutron activation analysis (INAA) was used without chemical preconcentration. Strongly varying compositions were observed for both the main and trace elements. Of particular interest were the high lanthanide and Th/U contents in these sediments.
The application of neutron activation analysis, scanning electron microscope, and radiographic imaging for the characterization of electrochemically …
2008
Lanthanide and actinide targets are prepared at the University of Mainz by molecular plating, an electrochemical deposition from an organic solvent, for heavy-ion reaction studies at GSI. To acquire information about deposition yield, target thickness, and target homogeneity, the following analysis methods are applied. With neutron activation analysis (NAA) the deposition yield and the average thickness of the deposited material is determined. We report on the analytical procedure of NAA performed subsequent to the molecular plating process. Scanning electron microscope (SEM) is used to determine the morphology of the target surfaces. In combination with energy dispersive X-ray spectrometer…
Insulin-dependent leptin expression in breast cancer cells.
2008
Abstract Pathologic conditions associated with hyperinsulinemia, such as obesity, metabolic syndrome, and diabetes, seem to increase the risk of breast cancer. Here, we studied molecular mechanisms by which insulin activates the expression of leptin, an obesity hormone that has been shown to promote breast cancer progression in an autocrine or paracrine way. Using MDA-MB-231 breast cancer cells, we found that (a) insulin stimulated leptin mRNA and protein expression, which was associated with increased activation of the leptin gene promoter; (b) insulin increased nuclear accumulation of transcription factors hypoxia inducible factor (HIF)-1α and Sp1 and their loading on the leptin promoter;…
Leptin/HER2 crosstalk in breast cancer: in vitro study and preliminary in vivo analysis.
2008
Abstract Background Obesity in postmenopausal women is associated with increased breast cancer risk, development of more aggressive tumors and resistance to certain anti-breast cancer treatments. Some of these effects might be mediated by obesity hormone leptin, acting independently or modulating other signaling pathways. Here we focused on the link between leptin and HER2. We tested if HER2 and the leptin receptor (ObR) can be coexpressed in breast cancer cell models, whether these two receptors can physically interact, and whether leptin can transactivate HER2. Next, we studied if leptin/ObR can coexist with HER2 in breast cancer tissues, and if presence of these two systems correlates wi…
Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids – differences in vivo and in vitro
2014
Summary Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native …
eNOS S-nitrosylates β-actin on Cys374 and regulates PKC-θ at the immune synapse by impairing actin binding to profilin-1.
2017
The actin cytoskeleton coordinates the organization of signaling microclusters at the immune synapse (IS); however, the mechanisms involved remain poorly understood. We show here that nitric oxide (NO) generated by endothelial nitric oxide synthase (eNOS) controls the coalescence of protein kinase C-¿ (PKC-¿) at the central supramolecular activation cluster (c-SMAC) of the IS. eNOS translocated with the Golgi to the IS and partially colocalized with F-actin around the c-SMAC. This resulted in reduced actin polymerization and centripetal retrograde flow of ß-actin and PKC-¿ from the lamellipodium-like distal (d)-SMAC, promoting PKC-¿ activation. Furthermore, eNOS-derived NO S-nitrosylated ß-…
Voluntary distance running prevents TNF-mediated liver injury in mice through alterations of the intrahepatic immune milieu
2017
AbstractPhysical activity confers a broad spectrum of health benefits. Beyond the obvious role in metabolically driven diseases, the role of physical activity in acute liver injury is poorly explored. To study the role of physical activity in acute liver injury, a novel model of voluntary distance running in mice was developed and mice were subjected to acute liver injury induced by N-galactosamine (GalN) and lipopolysaccharide (LPS). Analyses included histological stains, immunoblotting, qRT-PCR and FACS analysis. Voluntary distance running increased to an average of 10.3 km/day after a learning curve. Running lead to a decrease in the absolute numbers of intrahepatic CD4+ T and B lymphocy…