Search results for "ONJ"
showing 10 items of 1458 documents
Facile synthesis of 5β-cholane-sym-triazine conjugates starting from metformin and bile acid methyl esters: Liquid and solid state NMR characterizati…
2009
Abstract Four bile acid-triazine conjugates: N2′,N2′-dimethyl-6′-(3α-hydroxy-5β-24-norcholyl)-1′,3′,5′-triazine-2′,4′-diamine (lithocholyl triazine, 4a), N2′,N2′-dimethyl-6′-(3α,7α-dihydroxy-5β-24-norcholyl)-1′,3′,5′-triazine-2′,4′-diamine (chenodeoxycholyl triazine, 4b), N2′,N2′-dimethyl-6′6′-(3α,12α-dihydroxy-5β-24-norcholyl)-1′,3′,5′-triazine-2′,4′-diamine (deoxycholyl triazine) (4c), and N2′,N2′-dimethyl-6′-(3α,7α,12α-trihydroxy-5β-24-norcholyl)-1′,3′,5′-triazine-2′,4′-diamine (cholyl triazine) (4d) have been prepared and characterized by liquid and solid state NMR. An improved synthetic method produced better yields and an easier purification procedure for 4d than reported in the liter…
Bioaugmentācijas pielietošana notekūdeņu dūņu pārstrādes stimulēšanai
2020
Pirms dūņas varētu izmantot, kā augsnes mēslojumu, tās ir jāstabilizē, samazinot patogēnu, toksisko un organisko vielu daudzumu, kā arī samazinot smakojošu materiālu rašanos. Darba mērķis bija raksturot bioaugmentācijas un salmu pievienošanas ietekmi notekūdeņu dūņu paraugiem to pārstrādes stimulēšanai. Lai šo mērķi sasniegtu, dažādās kombinācijās, tika izveidoti dūņu, salmu, mikroorganismu un ūdeni saturoši eksperimentālie paraugi. Mikroorganismu elpošanas intensitāte, dažādu fizioloģisko grupu KVV skaits, kā arī veidotā amonjaka daudzums un fitotoksiskums tika uzskatīti kā svarīgākie parametri izvirzītā darba mērķa sasniegšanai. Darba rezultāti sniedz informāciju, ka kviešu salmi un bioau…
N-valproyl-aminoacids as new potential antiepileptic drugs: Synthesis, characterization and in vitro studies on stability
2015
Epilepsy, affecting at least 50 million persons worldwide, is one of the most common neurological disorders. Despite the significant advances in understanding epileptogenic mechanisms and in counteracting their pathological consequences, this clinical condition still has to be faced of treating more effectively the symptoms (epileptic seizures) and of preventing their unfavourable evolution. So far, research has been unsuccessful involved in developing effective antiepileptic drugs (AEDs) capable of preventing the development of the pathogenic process, set in motion by different etiological factors, that leads ultimately to chronic epilepsies .[1, 2] So, a substantial need remains to develo…
Silver Oxide Mediated Monotosylation of Poly(ethylene glycol) (PEG): Heterobifunctional PEG via Polymer Desymmetrization
2017
Heterobifunctional poly(ethylene glycol)s (PEGs) are key structures for bioconjugation in the context of the “PEGylation” strategy to enhance blood circulation times of, for example, peptide drugs or “stealth” liposomes. The formation of heterobifunctional PEGs from symmetric PEG diols is challenging because of limited yields of the targeted monofunctional product and difficulties associated with separation steps. On the basis of a detailed comparison of reaction conditions, we have investigated a “polymer desymmetrization” strategy to maximize the yields of monofunctional PEG tosylate. The tosylation reaction in the presence of the heterogeneous catalyst silver oxide and potassium iodide i…
Synthesis and Characterization of a Stable Copper(I) Complex for Radiopharmaceutical Applications
2014
A highly stable copper(I) complex was obtained starting from a copper(II) salt. This compound was characterized by a combination of several analytical techniques (UV/Vis spectroscopy, energy-dispersive X-ray spectroscopy, electrochemistry, and X-ray photoelectron spectroscopy) and was shown to present an N4Cu structure. These results were confirmed by a density functional calculations study of the binding energy and the electronic structure of model ligand and copper complexes. Preliminary tests of complexation showed a high ability of the corresponding ligand to chelate 64Cu in very diluted medium, which is of interest for developing new positron emission tomography imaging agents. The sta…
MANOTA: a promising bifunctional chelating agent for copper-64 immunoPET
2017
International audience; Improved bifunctional chelating agents (BFC) are required for copper-64 radiolabelling of monoclonal antibodies (mAbs) under mild conditions to yield stable, target-specific imaging agents. Four different bifunctional chelating agents (BFC) were evaluated for Fab (Fragment antigen binding) conjugation and radiolabelling with copper-64. Two DOTA- (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and two NOTA- (1,4,7-triazacyclononane-1,4,7-triacetic acid) derivatives bearing a p-benzyl-isothiocyanate group were conjugated to Fab-trastuzumab - which targets the HER2/neu receptor - and the average number of chelators attached ranged from 2.4 to 4.3 macrocycles …
Polyaspartamide-Doxorubicin Conjugate as Potential Prodrug for Anticancer Therapy
2015
Purpose To synthesize a new polymeric prodrug based on ?,?- poly(N-2-hydroxyethyl)(2-aminoethylcarbamate)-d,l-aspartamide copolymer bearing amine groups in the side chain (PHEA-EDA), covalently linked to the anticancer drug doxorubicin and to test its potential application in anticancer therapy. Methods The drug was previously derivatized with a biocompatible and hydrophilic linker, leading to a doxorubicin derivative highly reactive with amino groups of PHEA-EDA. The PHEAEDA- DOXO prodrug was characterized in terms of chemical stability. The pharmacokinetics, biodistribution and cytotoxicity of the product was investigated in vitro and in vivo on human breast cancer MCF-7 and T47D cell lin…
Preparation and preliminary biological screening of cholic acid–juvenoid conjugates
2020
Abstract Steroidal compounds have been utilized as carriers and for modification of physico-chemical properties of model biologically active secondary alcohols – juvenoids. Juvenoids are juvenile hormone analogues – environmentally safe insecticides, possessing significant biological activity towards different arthropods groups in focus on insect pest species. Structure modification of juvenoids plays important role to control the rate of liberation and decomposition of juvenoid in digestive system and can also play important role in the mode of action towards selected insect. This study presents an approach to the synthesis of steroidal monomers and dimers carrying one and two molecules of…
NOVEL COMPOSED GALACTOSYLATED NANODEVICES CONTAINING A RIBAVIRIN PRODRUG AS HEPATIC CELL-TARGETED CARRIERS FOR HCV TREATMENT
2013
In this paper, we describe the preparation of liver-targeted nanoparticles potentially able to carry to hepatocytes a ribavirin (RBV) prodrug, exploiting the presence of carbohydrate receptors in the liver (i.e., ASGPR in hepatocytes). These particles were obtained starting from a galactosylated phospholipid-polyaminoacid conjugate. This latter was obtained by chemical reaction of ALPHA, BETA -poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-DL-aspartamide (PHEA-EDA) with 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(succinyl) sodium salt (DPPE), and subsequent reaction with lactose, obtaining PHEA-EDA-DPPE-GAL copolymer. To enhance the entrapment into obtained nanostructures, a hydroph…
Experimental demonstration of phase bistability in a broad-area optical oscillator with injected signal
2015
We demonstrate experimentally that a broad-area laserlike optical oscillator (a nondegenerate photorefractive oscillator) with structured injected signal displays two-phase patterns. The technique [de Valc\'arcel and Staliunas, Phys. Rev. Lett. 105, 054101 (2010)] consists in spatially modulating the injection, so that its phase alternates periodically between two opposite values, i.e., differing by $\ensuremath{\pi}$.