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131.
132.
Silke C. Wenzel Holger Hoffmann Jidong Zhang Laurent Debussche Sabine Haag‐Richter Michael Kurz Frederico Nardi Peer Lukat Irene Kochems Heiko Tietgen Dietmar Schummer Jean‐Paul Nicolas Loreley Calvet Valerie Czepczor Patricia Vrignaud Agnes Mühlenweg Stefan Pelzer Rolf Müller Mark Brnstrup 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(51):15781-15785
133.
Supercritical fluid extraction (SFE) is a green alternative method of extraction for neutral lipids in seeds compared to conventional methods utilizing organic solvents. In this work, a novel method where SFE is hyphenated with an evaporative light scattering detector is presented. The method was subsequently applied to determine lipid content in crushed linseed. The new method enables rapid quantification of extracted lipids as well as be ability to continuously monitor the extraction rate in real-time, thus being able to determine the time point of completed extraction. 相似文献
134.
Antiviral Activity of Synthetic Aminopyrrolic Carbohydrate Binding Agents: Targeting the Glycans of Viral gp120 to Inhibit HIV Entry
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Dr. Oscar Francesconi Prof. Cristina Nativi Dr. Gabriele Gabrielli Irene De Simone Sam Noppen Prof. Jan Balzarini Prof. Sandra Liekens Dr. Stefano Roelens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(28):10089-10093
The binding abilities of a set of structurally related aminopyrrolic synthetic receptors for mannosides, endowed with antimycotic activity against yeast and yeast‐like pathogens bearing mannoproteins on their cell surface, have been investigated towards the highly mannosylated gp120 and gp41 glycoproteins of the HIV envelope. A pronounced binding interaction with both glycoproteins was observed by SPR for most of the investigated compounds. Comparison of their binding properties towards the glycoproteins with their binding affinities toward mannosides revealed a direct correlation, supporting their role as carbohydrate binding agents (CBAs). Cytostatic activity studies revealed antiproliferative activity dependent on the nature and the structure of compounds. Antiviral activity studies against a broad panel of DNA and RNA viruses showed inhibitory effect against HIV infection of the T‐lymphocyte CEM cell line for two compounds, suggesting antiviral activity similar to other CBAs, such as the nonpeptidic pradimicin antibiotics. 相似文献
135.
The main paper conservation methods are presented, classified in the following categories: preparation of the intervention, disinfestation and disinfection/sterilization, surface/dry cleaning, wet cleaning, chemical stabilization, paper repairs, consolidation and strengthening. Treatment documentation is also discussed. The targets, the historical aspects, the general principles, the materials and equipment, the acceptance and criticism pertaining to each method are briefly reviewed, and the most important research for their evaluation is presented. Several paper stabilization strategies, such as deacidification and iron gall ink stabilization, applicable to paper are elucidated. Specific consolidation and strengthening methods for paper, such as lamination and paper splitting are also discussed. The review mainly focuses on the established methods, but experimental, abandoned or insufficiently documented methods are also included. Shortcomings and limitations of several methods were found in the literature, concerning health issues, limited effectiveness, adverse side-effects on the treated artefacts and restricted applicability. 相似文献
136.
137.
Eleni Kalogria Athanasia Varvaresou Spyridon Papageorgiou Evaggelia Protopapa Ioannis Tsaknis Alexios Matikas Irene Panderi 《Chromatographia》2014,77(19-20):1275-1281
This article describes the development and validation of a selective high-performance liquid chromatography method that allows, after liquid–liquid extraction and pre-column derivatization reaction with quercetin, the quantification of aluminium chlorohydrate in antiperspirant creams. Chromatographic separation was achieved on an XTerra MS C18 analytical column (150 × 3.0 mm i.d., particle size 5 μm) using a mobile phase of acetonitrile:water (15:85, v/v) containing 0.08 % trifluoroacetic acid at a flow rate of 0.30 mL min?1. Ultraviolet spectrophotometric detection at 415 nm was used. The assay was linear over a concentration range of 3.7–30.6 μg mL?1 for aluminium with a limit of quantitation of 3.74 μg mL?1. Quality control samples (4.4, 17.1 and 30.6 μg mL?1) in five replicates from five different runs of analysis demonstrated intra-assay precision (% coefficient of variation <3.8 %), inter-assay precision (% coefficient of variation <5.4 %) and an overall accuracy (% recovery) between 96 and 101 %. The method was used to quantify aluminium in antiperspirant creams containing 11.0, 13.0 and 16.0 % (w/w) aluminium chlorohydrate, respectively. 相似文献
138.
Min Yao Chuan Gu Francis J. Doyle Jr. Hong Zhu Robert W. Redmond Irene E. Kochevar 《Photochemistry and photobiology》2014,90(2):297-305
Photosensitized protein cross‐linking has been recently developed to seal wounds and strengthen tissue. Although the photosensitizing dye, Rose Bengal (RB), is phototoxic to cultured cells, cytotoxicity does not accompany RB‐photosensitized tissue repair in vivo. We investigated whether the environment surrounding cells in tissue or the high irradiances used for photo–cross‐linking inhibited RB phototoxicity. Fibroblasts (FB) grown within collagen gels to mimic a tissue environment and monolayer cultured FB were treated with RB (0.01–1 mm ) and the high 532 nm laser irradiances used in vivo for tissue repair (0.10–0.50 W cm?2). Monolayer FB were substantially more sensitive to RB photosensitization: the LD50 was >200‐fold lower than that in collagen gels. Collagen gel protection was associated with increased Akt phosphorylation, a prosurvival pathway. RB phototoxicity in collagen gels was 25‐fold greater at low (0.030 W cm?2) that at high (0.50 W cm?2) irradiances. Oxygen depletion at high irradiance only partially accounted for the irradiance dependence of phototoxicity as replacing air with nitrogen only increased the LD50 by four‐fold in monolayers. These results indicate that the lack of RB phototoxicity during in vivo tissue repair results from upregulation of prosurvival pathways in tissue cells, oxygen depletion and irradiance‐dependent RB photochemistry. 相似文献
139.
A mixed quantum-classical formulation is developed for a quantum subsystem in strong interaction with an N-particle environment, to be treated as classical in the framework of a hydrodynamic representation. Starting from the quantum Liouville equation for the N-particle distribution and the corresponding reduced single-particle distribution, exact quantum hydrodynamic equations are obtained for the momentum moments of the single-particle distribution coupled to a discretized quantum subsystem. The quantum-classical limit is subsequently taken and the resulting hierarchy of equations is further approximated by various closure schemes. These include, in particular, (i) a Grad-Hermite-type closure, (ii) a Gaussian closure at the level of a quantum-classical local Maxwellian distribution, and (iii) a dynamical density functional theory approximation by which the hydrodynamic pressure term is replaced by a free energy functional derivative. The latter limit yields a mixed quantum-classical formulation which has previously been introduced by I. Burghardt and B. Bagchi, Chem. Phys. 134, 343 (2006). 相似文献
140.
Finocchio E Baccini I Cristiani C Dotelli G Gallo Stampino P Zampori L 《The journal of physical chemistry. A》2011,115(26):7484-7493
The intercalation of organic polymers molecules (i.e., PEGs and BRIJ) into a standard Ca-montmorillonite has been studied by XRD, TG, and IR spectroscopy. The polymer intercalation is confirmed by the increasing of the d(001) in XRD spectra as well as by the complex multisteps thermal decomposition behavior of the organo-clay materials. Mid-IR and diffuse reflectance near-IR spectra of the intercalated materials show the polymer diagnostic bands (CH stretching and deformation mode), shifted or changed in shape by the interaction with the clay matrix. Both PEG 1500 and PEG 4000 based materials are likely intercalated in an extended configuration, similar to the amorphous polymer form. BRIJ intercalated polymer spectra suggest the disordered conformation of the alkilic chain in a prevailing "gauche", poorly packed, conformation. Host montmorillonite IR bands, mainly OH and water stretching and deformation fundamentals, combination, and overtone bands, are reduced in intensity by polymer intercalation, pointing out an interaction, likely through H-bonding and/or a possible substitution of cations hydration water molecules. 相似文献