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Jan Tauchen Lukas Huml Ludvik Bortl Ivo Doskocil Veronika Jarosova Petr Marsik 《Natural product research》2019,33(18):2718-2721
Plants mentioned in this study have numerous records in traditional Peruvian medicine being used in treatment of cancer and other diseases likely to be associated with oxidative stress. Amongst the eight plant species tested, only Dysphania ambrosioides exhibited combinatory antioxidant and anti-proliferative effect on a broad spectrum of cancer cells (DPPH and ORAC values = 80.6 and 687.3 μg TE/mg extract, respectively; IC50 against Caco-2, HT-29 and Hep-G2 = 129.2, 69.9 and 130.6, respectively). Alkaloids and phenolic compounds might significantly contribute to anticancer/antioxidant activity of this plant. The results justify the traditional medicinal use of this plant. Our findings further suggest that D. ambrosioides might serve as a prospective material for further development of novel plant-based antioxidant and/or anti-proliferative agents. Detailed analysis of chemical composition together with toxicology assessments and in vivo antioxidant/anti-proliferative activity of this plant should be carried out in order to verify its potential practical use. 相似文献
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Michael Meier Dr. Lei Ji Dr. Jörn Nitsch Dr. Ivo Krummenacher Andrea Deißenberger Dr. Dominic Auerhammer Dr. Marius Schäfer Prof. Dr. Todd B. Marder Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(18):4707-4712
A novel thiophene-bridged donor–acceptor system was synthesized with a carbazole as donor and a borole as acceptor unit. The borole group was successfully installed via the tin–boron exchange reaction of 1,1-dimethyl-2,3,4,5-tetraphenylstannole with 9-(5-(dibromoboryl)thiophen-2-yl)carbazole. The effect of the borole on the optoelectronic properties of the donor–acceptor system was explored by spectroscopic (UV/Vis and fluorescence spectroscopy), electrochemical (cyclic voltammetry) and theoretical (TD-DFT) methods as well as by modifying its structure. The corresponding donor–acceptor compound bearing the widely employed dimesitylboryl acceptor group was also synthesized for comparison. 相似文献
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Anneli Kruve Riin Rebane Karin Kipper Maarja-Liisa Oldekop Hanno Evard Koit Herodes Pekka Ravio Ivo Leito 《Analytica chimica acta》2015
This is the part II of a tutorial review intending to give an overview of the state of the art of method validation in liquid chromatography mass spectrometry (LC–MS) and discuss specific issues that arise with MS (and MS–MS) detection in LC (as opposed to the “conventional” detectors). The Part II starts with briefly introducing the main quantitation methods and then addresses the performance related to quantification: linearity of signal, sensitivity, precision, trueness, accuracy, stability and measurement uncertainty. The last section is devoted to practical considerations in validation. With every performance characteristic its essence and terminology are addressed, the current status of treating it is reviewed and recommendations are given, how to handle it, specifically in the case of LC–MS methods. 相似文献
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Ivo Grabchev Evgenia Vasileva-Tonkova Desislava Staneva Paula Bosch Rositsa Kukeva Radostina Stoyanova 《International Journal of Polymer Analysis and Characterization》2018,23(1):45-57
A new polyamidoamine metallodendrimer modified with eight 1,8-naphthalimide units was synthesized. The Cu(II) complex has been investigated by EPR spectroscopy and it has shown that 17 copper ions have involved in the dendrimer complex. To confirm the presence of metallodendrimers on the cotton surface, scanning electron microscopy characterization has been used. In vitro antimicrobial activity of the metallodendrimer against different pathogens was investigated and compared to the dendrimer ligand free of copper ions. Both dendrimers were deposited on a cotton fabric and antibacterial activity of the treated cotton samples was investigated against model Gram-positive and Gram-negative bacteria. It has been shown that the studied dendrimers reduce bacterial growth and prevent the formation of biofilms. The metallodendrimer showed stronger antimicrobial and biofilm inhibiting abilities than those of the free of Cu(II) ions ligand. 相似文献
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Pascal Röthlisberger Fabienne Levi-Acobas Ivo Sarac Rémy Ricoux Jean-Pierre Mahy Piet Herdewijn Philippe Marlière Marcel Hollenstein 《Tetrahedron letters》2018,59(48):4241-4244
Abasic sites are amongst the most frequent DNA lesions and result from spontaneous hydrolysis of the glycosidic bond or from the removal of damaged nucleobases. These depurination events can also occur on free deoxyribonucleoside triphosphates present in cells and lead to the formation of an abasic site triphosphate of which very little is known. Herein, we report the synthesis and biochemical characterization of the minimal triphosphate dФTP. Unexpectedly, dФTP is tolerated by various DNA polymerases and the incorporation efficiency obeys the A-rule. Single incorporation of dФMP units were also observed opposite abasic sites and the addition of prosthetic molecules mimicking base-pairs do not seem to favor the process. 相似文献