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Computational Management Science - High levels of correlation among financial assets and extreme losses are typical during crises. In such situations, investing in few assets might be a better... 相似文献
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Josephine Blersch Dr. Vitor Francisco Catarina Rebelo Dr. Adrian Jiménez-Balsa Helena Antunes Dr. Carlo Gonzato Dr. Sandra Pinto Dr. Susana Simões Prof. Dr. Klaus Liedl Prof. Dr. Karsten Haupt Prof. Dr. Lino Ferreira 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(5):2001-2007
RNA-based therapies offer a wide range of therapeutic interventions including the treatment of skin diseases; however, the strategies to efficiently deliver these biomolecules are still limited due to obstacles related to the cellular uptake and cytoplasmic delivery. Herein, we report the synthesis of a triggerable polymeric nanoparticle (NP) library composed of 160 formulations, presenting physico-chemical diversity and differential responsiveness to light. Six formulations were more efficient (up to 500 %) than commercially available lipofectamine in gene-knockdown activity. These formulations showed differential internalization by skin cells and the endosomal escape was rapid (minutes range). The NPs were effective in the release of siRNA and miRNA. Acute skin wounds treated with the top hit NP complexed with miRNA-150-5p healed faster than wounds treated with scrambled miRNA. Light-activatable NPs offer a new strategy to topically deliver non-coding RNAs. 相似文献
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Dr. Sandra Arias Dr. Shahrouz Amini Dr. Justus Horsch Matthias Pretzler Prof. Annette Rompel Inga Melnyk Dmitrii Sychev Prof. Andreas Fery Prof. Hans G. Börner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18653-18657
Artificial mussel-glue proteins with pH-triggered cohesion control were synthesized by extending the tyrosinase activated polymerization of peptides to sequences with specific modules for cohesion control. The high propensity of these sequence sections to adopt β-sheets is suppressed by switch defects. This allows enzymatic activation and polymerization to proceed undisturbed. The β-sheet formation is regained after polymerization by changing the pH from 5.5 to 6.8, thereby triggering O→N acyl transfer rearrangements that activate the cohesion mechanism. The resulting artificial mussel glue proteins exhibit rapid adsorption on alumina surfaces. The coatings resist harsh hypersaline conditions, and reach remarkable adhesive energies of 2.64 mJ m−2 on silica at pH 6.8. In in situ switch experiments, the minor pH change increases the adhesive properties of a coating by 300 % and nanoindentation confirms the cohesion mechanism to improve bulk stiffness by around 200 %. 相似文献
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Water nucleophilic attack is an important step in water oxidation reactions, which have been widely studied using density functional theory (DFT). Nevertheless, a single-determinant DFT picture may be insufficient for a deeper insight into the process, in particular during the oxygen–oxygen bond formation. In this work, we use complete active space self-consistent field calculations and describe an approach for a complete active space analysis along a reaction pathway. This is applied to the water nucleophilic attack at a Ru-based catalyst, which has successfully been used for efficient water oxidation and in silico design of new water oxidation catalysts recently. 相似文献
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Yancho Zarev Kenn Foubert Paul Cos Louis Maes Esameldin Elgorashi Sandra Apers 《Natural product research》2020,34(7):1037-1040
AbstractSeven tetracyclic spiro-alkaloids, i.e. glucoerysodine (1), erysodine (2), epi-erythratidine (3), erysovine (4), erythratidine (5), erysotrine (6) and erythraline (7) were isolated from the seeds of Erythrina latissima by means of conventional separation methods and HPLC-DAD-SPE-NMR. Their structures were elucidated by spectroscopic means. This is the first report on the isolation of compounds 3, 5 and 6 from this plant. Antiplasmodial activity against the chloroquine-resistant strain Plasmodium falciparum K1 and cytotoxicity against MRC-5 cells (human fetal lung fibroblast cells) was assessed in vitro. Erysodine (2) and erysovine (4) showed moderate activity (IC50 6.53?µM and 4.05?µM, respectively), compared with the standard chloroquine (IC50 = 0.14?µM). No cytotoxicity was observed in a concentration up to 64.0?µM. 相似文献