Search results for "cyclic"
showing 10 items of 2439 documents
Functional C1-inhibitor diagnostics in hereditary angioedema: Assay evaluation and recommendations
2008
Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of potentially life-threatening angioedema. The most widespread underlying genetic deficiency is a heterozygous deficiency of the serine protease inhibitor Cl esterase inhibitor (C1-Inh). In addition to low C4 levels, the most important laboratory parameter for correct diagnosis of HAE or angioedema due to acquired C1-Inh deficiency is reduced C1-Inh function (fC1-Inh). No direct recommendations about the assays for fC1-Inh or sample handling conditions are available, although this would prove especially useful when a laboratory first starts to offer assays on fC1-Inh for HAE diagnosis. In the p…
Protection from graft-versus-host disease by HIV-1 envelope protein gp120-mediated activation of human CD4+CD25+ regulatory T cells.
2009
AbstractNaturally occurring CD4+CD25+ regulatory T cells (Tregs) represent a unique T-cell lineage that is endowed with the ability to actively suppress immune responses. Therefore, approaches to modulate Treg function in vivo could provide ways to enhance or reduce immune responses and lead to novel therapies. Here we show that the CD4 binding human immunodeficiency virus-1 envelope glycoprotein gp120 is a useful and potent tool for functional activation of human Tregs in vitro and in vivo. Gp120 activates human Tregs by binding and signaling through CD4. Upon stimulation with gp120, human Tregs accumulate cyclic adenosine monophosphate (cAMP) in their cytosol. Inhibition of endogeneous cA…
Fluorescence labelling of organic acidic compounds with 4-bromomethyl-7-methoxycoumarin (Br-Mmc)
1977
4-Bromomethyl-7-methoxycoumarin (Br-Mmc) is introduced as a fluorescence marker for aromatic and heterocyclic acids. To investigate the applicability of this method on substances of different chemical classes, screening experiments with 110 compounds were carried out using a microrefluxer. Most aromatic and heterocyclic monocarboxylic acids gave Mmc-esters which are fluorescent on thin-layer plates, like the Mmc-esters of fatty acids, which have been previously investigated. Strong acids, alcohols, amides and most amines did not react, whereas certain cyclic amines such as piperidine gave strongly fluorescent derivatives. Mmc-phenyl ethers shows only weak fluorescence. A new standard proced…
Photoactivatable caged cyclic RGD peptide for triggering integrin binding and cell adhesion to surfaces.
2011
We report the synthesis and properties of a photoactivatable caged RGD peptide and its application for phototriggering integrin- and cell-binding to surfaces. We analysed in detail 1) the differences in the integrin-binding affinity of the caged and uncaged forms by quartz crystal microbalance (QCM) studies, 2) the efficiency and yield of the photolytic uncaging reaction, 3) the biocompatibility of the photolysis by-products and irradiation conditions, 4) the possibility of site, temporal and density control of integrin-binding and therefore human cell attachment, and 5) the possibility of in situ generation of cell patterns and cell gradients by controlling the UV exposure. These studies p…
Preparation and evaluation of lauryl methacrylate monoliths with embedded silver nanoparticles for capillary electrochromatography
2012
In this article, capillary columns constituted by lauryl methacrylate monoliths with embedded silver nanoparticles (AgNPs) were developed and tested. Two incorporation approaches of AgNPs in monoliths were explored. The AgNPs were either photogenerated in situ during polymerization of the monolith by UV irradiation, or incorporated to the polymerization mixture (ex situ). The influence of the AgNP concentration on the morphological and chromatographic properties of the polymer matrix was investigated, and both the in situ and ex situ approaches were comparatively discussed. The morphology of the monoliths was characterized by electron microscopic techniques, and their electrochromatographic…
Molte Palermo. Temi
2019
Nel tema delle incompiute idee di città possibili si riconoscerà il paradigma connotativo dello stesso divenire di Palermo, lungo un percorso millenario di processi di trasformazione nessuno dei quali portato a compimento, in virtù di quel valore distintivo di exemplum che non necessita di ulteriori e conclusive dimostrazioni. Il corso della storia, del resto, ha imposto a Palermo il ciclico riproporsi di destini interrotti. Tale si rilevò l’invenzione della città capitale, quella della “quadratura geometrica e della croce di strade” sovrimpressa a quella archetipica e fondativa della Pan-ormos scambiatrice. E l’incompiutezza sarà il tratto distintivo della città dei rettifili stradali otto…
Synthesis and Antiproliferative Activity of Novel 3-(Indazol-3-yl)-quinazolin-4(3H)-one and 3-(Indazol-3-yl)-benzotriazin-4(3H)-one Derivatives
1999
Several new 3-(indazol-3-yl)-quinazolin-4(3H)-one and 3-(indazol-3-yl)-benzotriazin-4(3H)-one derivatives 5 and 6 were synthesized and tested for their in vitro antiproliferative activity against Raji, K562, and K562-R cell lines. The pharmacological screening showed that some 2, 6, or 7-substituted quinazolinones 5 posses a significant antiproliferative activity, with a percentage growth inhibition ranging from 44.8% to 100% at 50 microM, which was higher than that showed by the unsubstituted derivative 5a previously synthesized. For the most active compounds 5d, 5f, and 5g the IC50 were recorded.
Synthesis and antiproliferative activity of triazenoindazoles and triazenopyrazoles: a comparative study.
2003
Several triazenoindazoles and triazenopyrazoles were prepared transforming the appropriate aminoindazoles and aminopyrazoles in the corresponding diazonium salts which were reacted with dimethylamine, diethylamine and pyrrolidine. All the triazenes were tested for their antiproliferative activity against K562, HL60, L1210 and MCF7 cell lines. The biological data showed that the benzocondensation plays a positive role on the antiproliferative activity. The (1)H-NMR spectra showed that the rotational barrier around the N(2)-N(3) bond in the triazene group can be influenced both by the position of this group in the indazole nucleus and by the substitution pattern in the benzene moiety.
Functionalized 2-azabicyclo[3.3.1]nonanes. IV. synthesis of the indolo[3,2-f]morphan system.
1982
Abstract A short route to the 2-azabicyclo[3.3.1]nonan-7-one system is described. Condensation of 4-piperidones with diethyl 2-oxopropylphosphonate, followed by catalytic hydrogenation furnished the corresponding piperidylpropanones 6 which were cyclized with mercuric acetate in acetic acid to the target target bicyclic ketones 1 . The Fischer indole synthesis from 1 a afforded regioselectively the indole [3,2-f]morphan 2 , a new heteromorphan type.
Zur Reaktion von Indolen mit 1,3-Dithiolenium-Ionen: ein einfacher Zugang zu 3-(1,3-Dithiolan-2-yl)indolen
1986
Reaction of Indoles with 1,3-Dithiolenium Ions: a Simple Access to 3-(1,3-Dithiolan-2-yl)indoles 3-Unsubstituted indoles 1 react regioselectively with 2-methyl- and 2-phenyl-1,3-dithiolenium ions 2 under mild conditions to give the 3-(1,3-dithiolan-2-yl)indoles 4 as protected 3-acylindoles.