Search results for "imide"
showing 10 items of 298 documents
Synthesis of polymeric derivatives of isoniazid: characterization and in vitro release from a water-soluble adduct with polysuccinimide.
1989
Coupling of isoniazid with polysuccinimide afforded a water-insoluble polymeric pro-drug; by reaction with ethanolamine it was chemically transformed in a water-soluble adduct. The in vitro release of isoniazid from the drug-polymer adduct was studied by using an artificial stomach wall lipid membrane. The transfer rate constant from simulated gastric juice to simulated plasma was defined and compared with that of an equivalent dose of pure drug.
Acetylcholine and nicotine stimulate the release of granulocyte-macrophage colony stimulating factor from cultured human bronchial epithelial cells.
1998
Primary cultures of human bronchial epithelial cells (HBE-cells) were established to measure granulocyte-macrophage colony stimulating factor (GM-CSF) release. HBE-cells showed a basal GM-CSF release (82+/-20 ng/well/24 h; 30 donors), which was increased by interleukin-1 beta(IL-1beta, 1 ng/ml) by 270%. This effect was blocked by 1 microM dactinomycin or 10 microM cycloheximide, i.e. the stimulatory effect of IL-1beta depended on de-novo synthesis. Histamine (100 microM) and acetylcholine ( 100 nM) stimulated GM-CSF release more than two-fold above the baseline. Nicotine (1 microM) increased GM-CSF release to a similar extent, and this effect was prevented by 30 microM (+)-tubocurarine. The…
Induction of apoptosis in human retinoblastoma cells by topoisomerase inhibitors
1998
PURPOSE:To examine the apoptotic effect induced in human retinoblastoma Y79 cells by camptothecin, etoposide, and amsacrine, to examine the effect of these drugs on the expression of many apoptosis-related modulators, and to test the antiapoptotic effect exerted by insulin-like growth factor-I (IGF-I). METHODS:Morphologic features of apoptosis were demonstrated using acridine orange- ethidium bromide staining and electron microscopy. DNA fragmentation was determined by means of an in situ cell detection procedure (TdT-dUTP terminal nick-end labeling [TUNEL]) or by electrophoresis on agarose gels and was quantified by enzyme-linked immunosorbent assay. The expression of apoptosis-related mod…
Novel 3-Azaindolyl-4-arylmaleimides Exhibiting Potent Antiangiogenic Efficacy, Protein Kinase Inhibition, and Antiproliferative Activity
2012
Tumor growth and metastasis are highly associated with the overexpression of protein kinases (PKs) regulating cell growth, apoptosis resistance, and prolonged cell survival. This study describes novel azaindolyl-maleimides with significant inhibition of PKs, such as VEGFR, FLT-3, and GSK-3β which are related to carcinogenesis. Furthermore, these compounds exhibit high kinase selectivity and potent inhibition of angiogenesis and cell proliferation, offering versatile options in cancer treatment strategies.
[3.3]Ferrocenophanes with guanidine bridging units as multisignalling receptor molecules for selective recognition of anions, cations, and amino acid…
2007
The synthesis, electrochemical, and optical properties of a new [3.3]ferrocenophane framework in which two ferrocene subunits, with similar electronic environments, are linked through two substituted guanidine moieties, are reported. The receptors 4-7 have been prepared in good yields by the reaction of bis(carbodiimide) 3 with primary amines. This architecture is exceptionally "tunable" because a variety of "legs" may be appended to the basic [3.3]ferrocenophane scaffold to give a wide range of signaling units. These receptors show remarkable ion-sensing properties, due to the presence of a redox active unit (ferrocene), and an amphoteric binding site (guanidine). In this nitrogen-rich str…
Intramolecular electronic excitation energy transfer in donor∕acceptor dyads studied by time and frequency resolved single molecule spectroscopy
2008
Electronic excitation energy transfer has been studied by single molecule spectroscopy in donor/acceptor dyads composed of a perylenediimide donor and a terrylenediimide acceptor linked by oligo(phenylene) bridges of two different lengths. For the shorter bridge (three phenylene units) energy is transferred almost quantitatively from the donor to the acceptor, while for the longer bridge (seven phenylene units) energy transfer is less efficient as indicated by the occurrence of donor and acceptor emission. To determine energy transfer rates and efficiencies at the single molecule level, several methods have been employed. These comprise time-correlated single photon counting techniques at r…
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…
Study of separation of water + 2-propanol mixture using different ionic liquids: 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-b…
2018
Abstract The liquid–liquid equilibria data of water (1) + 2-propanol (2) + [bmim][Tf2N] (3) and water (1) + 2-propanol (2) + [bmp][Tf2N] (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were measured with the objective of understanding the behavior of these two systems and to try to improve the extraction of 2-propanol from water from economical and environmental points of view. The thermodynamic parameters were determined using the non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models, and excellent results were achieved in both cases (the maximum root-mean-square deviation was 0.433%). Lastly, the capability of the two ionic liquids to separate 2-propanol from …
Measurement and correlation of liquid-liquid equilibria at different temperatures in water + 1-propanol + 1-ethyl-3-methylimidazolium bis(trifluorome…
2016
Abstract In order to reduce the environmental impact and the economical costs of the separation of 1-propanol from aqueous mixtures, which enables the recycling of the alcohol, the experimental liquid-liquid equilibria (LLE) data of water (1) + 1-propanol (2) + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]) (3) and water (1) + 1-propanol (2) + 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([hmim][Tf2N]) (3) systems were measured in this work at different temperatures: 283.2, 303.2 and 323.2 K at atmospheric pressure. The results were correlated by non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models with good results in both…
INFγ stimulates arginine transport through system y+L in human monocytes
2004
Freshly isolated human monocytes transport L-arginine mostly through a sodium independent, NEM insensitive pathway inhibited by L-leucine in the presence, but not in the absence of sodium. Interferon-gamma (IFNgamma) stimulates this pathway, identifiable with system y+L, and markedly enhances the expression of SLC7A7, the gene that encodes for system y+L subunit y+LAT1, but not of SLC7A6, that codes for the alternative subunit y+LAT2. System y+ plays a minor role in arginine uptake by monocytes and the expression of system y+-related genes, SLC7A1 and SLC7A2, is not changed by IFNgamma. These results demonstrate that system y+L is sensitive to IFNgamma.