Search results for "Imides"
showing 10 items of 59 documents
Components of an antigen-/T cell receptor-independent pathway of lymphokine production
1991
The general way to induce the synthesis of lymphokines by T cells is the stimulation through the T cell receptor (TcR) complex which results in an increase of intracellular [Ca2+] and in the activation of a tyrosine kinase as well as of protein kinase C. Lymphokine production induced via the TcR is inhibited by the immunosuppressive drug cyclosporin A (CsA). However, an alternative pathway of lymphokine production exists. Several T lymphocyte clones can synthesize interferon-gamma (IFN-gamma), granulocyte-monocyte colony-stimulating factor, and small amounts of interleukin (IL3) when stimulated with syngeneic or allogeneic accessory cells (AC) plus IL2. In contrast to the TcR pathway the al…
CD36 is involved in lycopene and lutein uptake by adipocytes and adipose tissue cultures
2011
International audience; Scope: Carotenoids are mainly stored in adipose tissue. However, nothing is known regarding the uptake of carotenoids by adipocytes. Thus, our study explored the mechanism by which lycopene and lutein, two major human plasma carotenoids, are transported. Methods and results: CD36 was a putative candidate for this uptake, 3T3-L1 cells were treated with sulfosuccinimidyl oleate, a CD36-specific inhibitor. sulfosuccinimidyl oleate-treated cells showed a significant decrease in both lycopene and lutein uptake as compared to control cells. Their uptake was also decreased by partial inhibition of CD36 expression using siRNA, whereas the overexpression of CD36 in Cos-1 cell…
Link between Intestinal CD36 Ligand Binding and Satiety Induced by a High Protein Diet in Mice
2012
International audience; CD36 is a ubiquitous membrane glycoprotein that binds long-chain fatty acids. The presence of a functional CD36 is required for the induction of satiety by a lipid load and its role as a lipid receptor driving cellular signal has recently been demonstrated. Our project aimed to further explore the role of intestinal CD36 in the regulation of food intake. Duodenal infusions of vehicle or sulfo-N-succinimidyl-oleate (SSO) was performed prior to acute infusions of saline or Intralipid (IL) in mice. Infusion of minute quantities of IL induced a decrease in food intake (FI) compared to saline. Infusion of SSO had the same effect but no additive inhibitory effect was obser…
Differential Regulatory Capacity of CD25+ T Regulatory Cells and Preactivated CD25+ T Regulatory Cells on Development, Functional Activation, and Pro…
2004
Abstract CD25+ T regulatory (Treg) cells play a central role regarding the maintenance of peripheral tolerance via suppression of autoaggressive CD4+ T cells, CD8+ T cells, and Th1 cells. In this study we demonstrate that CD25+ Treg cells can also suppress the differentiation of murine conventional CD4+ T cells toward Th2 cells in a contact-dependent manner. However, the cytokine production and proliferation of established Th2 cells could not be inhibited by freshly isolated CD25+ Treg cells, whereas a strong inhibition of differentiated Th2 cells by in vitro preactivated CD25+ Treg cells could be observed. Inhibition of both conventional CD4+ T cells and Th2 cells is accompanied by a stron…
Moguntinones--new selective inhibitors for the treatment of human colorectal cancer.
2014
Abstract 3-Indolyl and 3-azaindolyl-4-aryl maleimide derivatives, called moguntinones (MOG), have been selected for their ability to inhibit protein kinases associated with angiogenesis and induce apoptosis. Here, we characterize their mode of action and their potential clinical value in human colorectal cancer in vitro and in vivo. MOG-19 and MOG-13 were characterized in vitro using kinase, viability, and apoptosis assays in different human colon cancer (HT-29, HCT-116, Caco-2, and SW480) and normal colon cell lines (CCD-18Co, FHC, and HCoEpiC) alone or in combination with topoisomerase I inhibitors. Intracellular signaling pathways were analyzed by Western blotting. To determine their pot…
Hierarchical Self-Organization of Perylene Bisimide–Melamine Assemblies to Fluorescent Mesoscopic Superstructures
2000
A series of three perylene tetracarboxylic acid bisimide dyes 3a-c bearing phenoxy substituents at the four bay positions of the perylene core were synthesized and their complexation behavior to complementary ditopic dialkyl melamines 8a-c was investigated. Binding constants and Gibbs binding energies for the hydrogen bonds between the imide and the complementary melamine moiety have been determined in several solvents by NMR and UV/Vis titration experiments with monotopic model compounds 5 and 9. The effects of the solvent polarity and specific solvent-solute interactions on the degree of polymerization of (3 x 8)n are discussed, and a general formula to estimate the chain length of [AA-BB…
Visible-light driven oxidation of gaseous aliphatic alcohols to the corresponding carbonyls via TiO2 sensitized by a perylene derivative
2013
Sensitized P25 TiO2 was prepared by wet impregnation with a home-prepared perylene dye, i.e., N,N?-bis(2-(1- piperazino)ethyl)-3,4,9,10-perylene-tetracarboxylic acid diimide dichloride (PZPER). Energy levels of PZPER were found to be compatible with those of TiO2 allowing fast electron transfer. The obtained catalyst has been characterized and used in the gas-phase partial oxidation of aliphatic primary and secondary alcohols, i.e., methanol, ethanol, and 2- propanol. The reaction was carried out under cut-off (?> 400 nm) simulated solar radiation in O2 atmosphere. The perylene derivative allowed a good absorbance of visible radiation thanks to its low optical energy gap (2.6 eV) which was …
Metal NHC Complexes with Naphthalimide Ligands as DNA-Interacting Antiproliferative Agents
2017
Naphthalimide-based N-heterocyclic carbene (NHC) complexes of the type [(1,5-cyclooctadiene)(NHC)RhCl)] (4 a-c), [(p-cymene)(NHC)RuCl2 )] (5 a-c), and [(NHC)CuBr] (6 a-c) were synthesized and investigated as antiproliferative agents that target DNA. The cytotoxic effects were largely driven by the naphthalimide structure, which is a DNA-intercalating moiety. Regarding the metal center, the highest activities were observed with the rhodium complexes, and cytotoxic activity was significantly lower for the ruthenium derivatives. The stable coordination of the NHC ligands of selected complexes 4 b and 5 b in solution was confirmed, and their DNA binding properties were studied by UV/Vis spectro…
“Cysteinyl leukotriene-1 receptor activation in a human bronchial epithelial cell line leads to signal transducer and activator of transcription 1-me…
2008
Abstract We studied the effect of leukotriene D(4) (LTD(4)) on a human bronchial epithelial cell line (16HBE) overexpressing the cysteinyl leukotriene (CysLT) (1) receptor (HBECysLT(1)R), looking at the associated signal transduction mechanisms as well as at effects on inflammatory cell adhesion. The results obtained showed that LTD(4) increases the phosphorylation of extracellular signal-regulated protein kinase (ERK) 1/2 and of the signal transducer and activator of transcription 1 (STAT-1) in serine 727 (STAT-1Ser727), resulting in increased eosinophil adhesion to HBECysLT(1)R, associated with enhanced surface expression of intercellular adhesion molecule (ICAM) 1. Pretreatment with a Cy…
Processing of O6-methylguanine into DNA double-strand breaks requires two rounds of replication whereas apoptosis is also induced in subsequent cell …
2009
The DNA adduct O(6)-methylguanine (O(6)MeG) induced by environmental genotoxins and anticancer drugs is a highly mutagenic, genotoxic and apoptotic lesion. Apoptosis induced by O(6)MeG requires mismatch repair (MMR) and proliferation. Models of O(6)MeG-triggered cell death postulate that O(6)MeG/T mispairs activate MMR giving rise to either direct genotoxic signaling or secondary lesions that trigger apoptotic signaling in the 2(nd) replication cycle. To test these hypotheses, we used a highly synchronized cell system competent and deficient for the repair of O(6)MeG adducts, which were induced by the S(N)1 methylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). We show that DNA doub…