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601.
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Andreea Ionescu Rossella Caligiuri Nicolas Godbert Loredana Ricciardi Massimo La Deda Mauro Ghedini Nicola Ferri Maria Giovanna Lupo Giorgio Facchetti Isabella Rimoldi Iolinda Aiello 《应用有机金属化学》2020,34(3):e5455
The in vitro biological activity towards the MDA-MB-231 triple-negative breast cancer cell line of two different series of anionic Pt(II) organometallic complexes was tested. For the first time, cytotoxic activity of anionic Pt(II) complexes has been observed. The anionic compounds of general formula NBu4[(C^N)Pt(O^O)], where (C^N) represents the cyclometalated form of 2-phenylpyridine (H(PhPy)), 2-thienylpyridine (H(Thpy)) or 2-benzo[h]quinoline (H(Bzq)), feature two different (O^O) chelated ligands: tetrabromocatechol [BrCat]2− ( 1 – 3 ) or alizarine [Aliz]2− ( 4 – 6 ). Complexes 1 – 6 displayed a significant cytotoxic effect against the studied cell line (IC50 range of 1.9–52.8 μM). For BrCat-containing complexes 1 – 3 , the biological activity was independent of the nature of the coordinated (C^N) ligand. In contrast, in the case of 4 – 6 , the cytotoxicity (significantly high for 4 ) was concomitantly induced by the presence of either the PhPy or the [Aliz]2− ligand. Since complexes 1–6 are emissive in solution, the potential use of 4 as a theranostic agent was investigated using confocal analysis. The fluorescence signal from MDA-MB-231 cells incubated with 4 indicated the localization of the compound into the cytosol region. 相似文献
603.
Dr. Marta Perez-Lloret Dr. Aurore Fraix Dr. Salvatore Petralia Dr. Sabrina Conoci Dr. Virginie Tafani Dr. Giovanna Cutrone Prof. Antonio Vargas-Berenguel Dr. Ruxandra Gref Prof. Salvatore Sortino 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14638-14643
A simple and green synthetic protocol for the rapid and effective preparation of Ag, Au and Au@Ag core–shell nanoparticles (NPs) is reported based on the light irradiation of a biocompatible, water-soluble dextran functionalized with benzophenone (BP) in the presence of AgNO3, HAuCl4, or both. Photoactivation of the BP moiety produces the highly reducing ketyl radicals through fast (<50 ns) intramolecular H-abstraction from the dextran scaffold, which, in turn, ensures excellent dispersibility of the obtained metal NPs in water. The antibacterial activity of the AgNPs and the photothermal action of the Au@Ag core–shell are also shown. 相似文献
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Lilian Dolores Chel-Guerrero Gabriela Castaeda-Corral Misael Lpez-Castillo Matteo Scampicchio Ksenia Morozova Julio Enrique Oney-Montalvo Giovanna Ferrentino Juan Jos Acevedo-Fernndez Ingrid Mayanín Rodríguez-Buenfil 《Molecules (Basel, Switzerland)》2022,27(4)
By-products of Capsicum chinense Jacq., var Jaguar could be a source of bioactive compounds. Therefore, we evaluated the anti-inflammatory effect, antioxidant activity, and their relationship with the polyphenol content of extracts of habanero pepper by-products obtained from plants grown on black or red soils of Yucatán, Mexico. Moreover, the impact of the type of extraction on their activities was evaluated. The dry by-product extracts were obtained by maceration (ME), Soxhlet (SOX), and supercritical fluid extraction (SFE). Afterward, the in vivo anti-inflammatory effect (TPA-induced ear inflammation) and the in vitro antioxidant activity (ABTS) were evaluated. Finally, the polyphenolic content was quantified by Ultra-Performance Liquid Chromatography (UPLC), and its correlation with both bioactivities was analyzed. The results showed that the SFE extract of stems of plants grown on red soil yielded the highest anti-inflammatory effect (66.1 ± 3.1%), while the extracts obtained by ME and SOX had the highest antioxidant activity (2.80 ± 0.0052 mM Trolox equivalent) and polyphenol content (3280 ± 15.59 mg·100 g−1 dry basis), respectively. A negative correlation between the anti-inflammatory effect, the antioxidant activity, and the polyphenolic content was found. Overall, the present study proposed C. chinense by-products as a valuable source of compounds with anti-inflammatory effect and antioxidant activity. 相似文献
606.
Giovanna Speranza CarloF. Morelli Maximilian Orlandi Mauro Scarpellini Paolo Manitto 《Helvetica chimica acta》2001,84(2):335-344
18O‐Substituted propane‐1,2‐diols and meso‐butane‐1,2‐diols were synthesized and fed to growing cells of Lactobacillus brevis. Propan‐1‐ol and butan‐2‐ol, prepared from such diols through diol‐dehydratase‐catalyzed dehydration followed by intracellular reduction, were analyzed for their 18O‐content. For each propane‐1,2‐diol enantiomer, partial retention or complete loss of the isotope appeared to be related to the mode of substrate binding. Specific retention of the O‐atom linked to the (R)‐configured C‐atom of meso‐butane‐1,2‐diol indicates that the diol dehydratase handles this substrate like (R)‐propane‐1,2‐diol. 相似文献
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609.
Giovanna Bonfanti Fabio Luterotti 《Mathematical Methods in the Applied Sciences》1998,21(12):1085-1105
A phase–field model based on the Coleman–Gurtin heat flux law is considered. The resulting system of non-linear parabolic equations, associated with a set of initial and Neumann boundary conditions, is studied. Existence, uniqueness, and regularity results are proved. An asymptotic analysis is also carried out, in the case where the coefficient of the interfacial energy term tends to 0. © 1998 B. G. Teubner Stuttgart—John Wiley & Sons, Ltd. 相似文献