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Vassiliki Damakoudi Tobias Feldner Edina Dilji Andrey Belkin Prof. Clemens Richert 《Chembiochem : a European journal of chemical biology》2021,22(5):924-930
Messenger RNA (mRNA) is emerging as an attractive biopolymer for therapy and vaccination. To become suitable for vaccination, mRNA is usually converted to a biomaterial, using cationic peptides, polymers or lipids. An alternative form of converting mRNA into a material is demonstrated that uses branched oligoribonucleotide hybrids with the ability to hybridize with one or more regions of the mRNA sequence. Two such hybrids with hexamer arms and adamantane tetraol as branching element were prepared by solution-phase synthesis. When a rabies mRNA was treated with the branched hybrids at 1 M NaCl concentration, biomaterials formed that contained both of the nucleic acids. These results show that branched oligoribonucleotides are an alternative to the often toxic reagents commonly used to formulate mRNA for medical applications. 相似文献
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Emese Rka Blint Gabriella Fr Balzs Kui Zsolt Balla Eszter Sra Kormnyos Erik Mrk Orjn Brigitta Tth Gyngyi Horvth Edina Szcs Sndor Benyhe Eszter Ducza Petra Pallagi Jzsef Malth Viktria Venglovecz Pter Hegyi Lrnd Kiss Zoltn Rakonczay Jr. 《International journal of molecular sciences》2022,23(3)
Opioids are widely used for the pain management of acute pancreatitis (AP), but their impact on disease progression is unclear. Therefore, our aim was to study the effects of clinically relevant opioids on the severity of experimental AP. Various doses of fentanyl, morphine, or buprenorphine were administered as pre- and/or post-treatments in rats. Necrotizing AP was induced by the intraperitoneal injection of L-ornithine-HCl or intra-ductal injection of Na-taurocholate, while intraperitoneal caerulein administration caused edematous AP. Disease severity was determined by laboratory and histological measurements. Mu opioid receptor (MOR) expression and function was assessed in control and AP animals. MOR was expressed in both the pancreas and brain. The pancreatic expression and function of MOR were reduced in AP. Fentanyl post-treatment reduced necrotizing AP severity, whereas pre-treatment exacerbated it. Fentanyl did not affect the outcome of edematous AP. Morphine decreased vacuolization in edematous AP, while buprenorphine pre-treatment increased pancreatic edema during AP. The overall effects of morphine on disease severity were negligible. In conclusion, the type, dosing, administration route, and timing of opioid treatment can influence the effects of opioids on AP severity. Fentanyl post-treatment proved to be beneficial in AP. Clinical studies are needed to determine which opioids are best in AP. 相似文献
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A large number of high‐density polyethylene (HDPE) powder samples produced by Phillips technology were taken from an industrial polymerization reactor and their catalyst residue content was determined by X‐ray fluorescence spectroscopy. The chemical structure of the powder was characterized by diffuse reflectance infrared spectroscopy (DRIFT), while the functional group content of samples processed in the presence and absence of a phenolic antioxidant was determined by Fourier transform infrared spectroscopy (FTIR). The melt flow index (MFI) of all processed samples was measured. Oxygen induction time (OIT) measurements were carried out to characterize the oxidative stability of 15 selected stabilized samples. The results indicate that the distribution of both the amount of chromium‐based catalyst residues and their composition are very heterogeneous in the produced polymer. With increasing catalyst residue content, the concentration of double bonds increases in the samples extruded with or without stabilizer. Viscosity was not influenced by catalyst residues, while discoloration increased slightly with increasing catalyst residue content. The stability of the processed polymer also depends on the concentration of double bonds and on other factors. Since other components of the catalyst, including the SiO2 support, also take part in the reactions occurring during processing, chromium content is not the sole, and perhaps not even the decisive, factor determining the properties and especially the stability of HDPE produced by a Phillips catalyst. 相似文献
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Edina Rusen Bogdan Marculescu Nicoleta Preda Cristina Bucur Lucian Mihut 《Polymer Bulletin》2008,61(5):581-592
Summary The effect of fullerene on the radical polymerization of N-vinylpyrrolidone with lauroyl peroxide
in toluene was investigated kinetically. C60 was found to act both as inhibitor
and as retarder because the polymerization rate and the molecular weight of resulting poly(vinylpyrrolidone)
is decreasing with the increase of the fullerene concentration (0-6.94 x 10-4
mol l-1). The water-soluble poly(vinylpyrrolidone)-modified fullerene C60
compound was characterized by differential scanning calorimetric, Infrared and Raman spectroscopy, UV
absorption and photoluminescence. Based on the results obtained by optical measurements, it is argued
that by the covalent attachment of the polymeric radicals to fullerene cage the extended electronic
conjugation system of the C60 is broken leading to the appearance of a polyene
structure. 相似文献
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Teodora Zecheru Traian Rotariu Edina Rusen Bogdan Mărculescu Florin Miculescu Laura Alexandrescu Iulian Antoniac Izabela-Cristina Stancu 《Journal of materials science. Materials in medicine》2010,21(10):2793-2804
In the present study polymeric microbeads of poly(2-hydroxyethyl methacrylate-co-dodecyl methacrylate-co-acrylic acid) or
p(HEMA-co-dDMA-co-AA) were synthesised and characterized through FT-IR and scanning electron microscopy (SEM); their swelling
behavior against saline solution was explored and their in vitro cytotoxicity was evaluated. Further, in order to elucidate
kinetic aspects regarding the ternary system p(HEMA-co-dDMA-co-AA), a mathematical model of the reactivity ratios of the comonomers
in the terpolymer has been conceived and analyzed. An intensified tendency of AA units accumulation in the copolymer has been
noticed, in spite of HEMA units, while dDMA conserves in the copolymer the fraction from the feed. Three compositions have
been selected for nafcillin-loading and their in vitro release capacity was evaluated. The compositions of 80:10:10 and 75:10:15 M
ratios appear suitable for further in vivo testing, in order to be used as drug delivery systems in the treatment of different
osseous diseases. 相似文献
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Gabriela Toader Edina Rusen Mircea Teodorescu Aurel Diacon Paul O. Stanescu Celina Damian Traian Rotariu Adrian Rotariu 《应用聚合物科学杂志》2017,134(28)
Polyurea nanocomposites represent a promising option in the development of advanced materials for applications that require high mechanical resistance. This article describes an optimized synthetic route for obtaining polyurea nanocomposites with enhanced mechanical properties by employing epoxy‐functionalized multiwalled carbon nanotubes (MWCNTs) as reinforcing agent. The experimental measurements revealed that these functionalized nanofillers have a positive effect on the properties of the composite only until they reach a certain concentration; therefore, the optimal composition was reported (the samples containing 0.2 weight % functionalized MWCNTs). The functionalization of the MWCNTs was confirmed through RAMAN, X‐ray photoelectron spectroscopy, scanning electron microscopy and thermogravimetric analysis, while the polyurea nanocomposites obtained have been characterized by thermal (differential scanning calorimetry and TGA) and mechanical (dynamic mechanical analysis and tensile tests) analyses. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45061. 相似文献
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Russell A. Jurenka Coby Schal Edina Burns Jody Chase Gary J. Blomquist 《Journal of chemical ecology》1989,15(3):939-949
The structural relationships between the cuticular hydrocarbons and the contact sex pheromone of the female German cockroach,Blattella germanica, were investigated. Cuticular hexane extracts were separated into hydrocarbon and ketone fractions by TLC or silicic acid column chromatography. The ketone fraction (which contains the major contact sex pheromone component) was analyzed by GC-MS before and after reduction to ydrocarbon. In addition to 3,11-dimethyl-2-nonacosanone, 3,11-dimethyl-2-heptacosanone was also identified. Females have the 3,11- and 3,9-dimethyl C27 and C29 alkanes, but only the 3,11- isomer of the dimethylketones. Inddition to the hydrocarbon components previously reported, a number of new components were characterized. Although the ratios of cuticular hydrocarbons differ among nymphs, adult males, and adult females, they have qualitatively identical hydrocarbon profiles, suggesting that the production of the contact sex pheromone results from the sex-specific oxidation of 3,11-imethylalkanes to pheromone components by the female. 相似文献