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601.
Stefano DallAcqua Kouadio Ibrahime Sinan Stefania Sut Irene Ferrarese Ouattara Katinan Etienne Mohamad Fawzi Mahomoodally Devina Lobine Gokhan Zengin 《Molecules (Basel, Switzerland)》2021,26(7)
Croton hirtus L’Hér methanol extract was studied by NMR and two different LC-DAD-MSn using electrospray (ESI) and atmospheric pressure chemical ionization (APCI) sources to obtain a quali-quantitative fingerprint. Forty different phytochemicals were identified, and twenty of them were quantified, whereas the main constituents were dihydro α ionol-O-[arabinosil(1-6) glucoside] (133 mg/g), dihydro β ionol-O-[arabinosil(1-6) glucoside] (80 mg/g), β-sitosterol (49 mg/g), and isorhamnetin-3-O-rutinoside (26 mg/g). C. hirtus was extracted with different solvents—namely, water, methanol, dichloromethane, and ethyl acetate—and the extracts were assayed using different in vitro tests. The methanolic extracts presented the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) values. All the tested extracts exhibited inhibitory effects on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with a higher activity observed for dichloromethane (AChE: 5.03 and BChE: 16.41 mgGALAE/g), while the methanolic extract showed highest impact against tyrosinase (49.83 mgKAE/g). Taken together, these findings suggest C. hirtus as a novel source of bioactive phytochemicals with potential for commercial development. 相似文献
602.
Vittoria Graziani Nicoletta Potenza Brigida DAbrosca Teresa Troiani Stefania Napolitano Antonio Fiorentino Monica Scognamiglio 《Molecules (Basel, Switzerland)》2021,26(11)
In the search of new natural products to be explored as possible anticancer drugs, two plant species, namely Ononis diffusa and Ononis variegata, were screened against colorectal cancer cell lines. The cytotoxic activity of the crude extracts was tested on a panel of colon cancer cell models including cetuximab-sensitive (Caco-2, GEO, SW48), intrinsic (HT-29 and HCT-116), and acquired (GEO-CR, SW48-CR) cetuximab-resistant cell lines. Ononis diffusa showed remarkable cytotoxic activity, especially on the cetuximab-resistant cell lines. The active extract composition was determined by NMR analysis. Given its complexity, a partial purification was then carried out. The fractions obtained were again tested for their biological activity and their metabolite content was determined by 1D and 2D NMR analysis. The study led to the identification of a fraction enriched in oxylipins that showed a 92% growth inhibition of the HT-29 cell line at a concentration of 50 µg/mL. 相似文献
603.
604.
Back Cover: Enhanced Thermal Oxidation Stability of Reduced Graphene Oxide by Nitrogen Doping (Chem. Eur. J. 38/2014)
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605.
Design of Decorin‐Based Peptides That Bind to Collagen I and their Potential as Adhesion Moieties in Biomaterials
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Dr. Stefania Federico Dr. Benjamin F. Pierce Dr. Susanna Piluso Dr. Christian Wischke Prof. Dr. Andreas Lendlein Dr. Axel T. Neffe 《Angewandte Chemie (International ed. in English)》2015,54(37):10980-10984
Mimicking the binding epitopes of protein–protein interactions by using small peptides is important for generating modular biomimetic systems. A strategy is described for the design of such bioactive peptides without accessible structural data for the targeted interaction, and the effect of incorporating such adhesion peptides in complex biomaterial systems is demonstrated. The highly repetitive structure of decorin was analyzed to identify peptides that are representative of the inner and outer surface, and it was shown that only peptides based on the inner surface of decorin bind to collagen. The peptide with the highest binding affinity for collagen I, LHERHLNNN, served to slow down the diffusion of a conjugated dye in a collagen gel, while its dimer could physically crosslink collagen, thereby enhancing the elastic modulus of the gel by one order of magnitude. These results show the potential of the identified peptides for the design of biomaterials for applications in regenerative medicine. 相似文献
606.
Novel Composite Plastics Containing Silver(I) Acylpyrazolonato Additives Display Potent Antimicrobial Activity by Contact
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Prof. Fabio Marchetti Dr. Jessica Palmucci Prof. Claudio Pettinari Dr. Riccardo Pettinari Dr. Francesca Condello Dr. Stefano Ferraro Dr. Mirko Marangoni Prof. Alessandra Crispini Dr. Stefania Scuri Prof. Iolanda Grappasonni Prof. Mario Cocchioni Dr. Massimo Nabissi Dr. Michele R. Chierotti Prof. Roberto Gobetto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):836-850
New silver(I) acylpyrazolonato derivatives displaying a mononuclear, polynuclear, or ionic nature, as a function of the ancillary azole ligands used in the synthesis, have been fully characterized by thermal analysis, solution NMR spectroscopy, solid‐state IR and NMR spectroscopies, and X‐ray diffraction techniques. These derivatives have been embedded in polyethylene (PE) matrix, and the antimicrobial activity of the composite materials has been tested against three bacterial strains (E. coli, P. aeruginosa, and S. aureus): Most of the composites show antimicrobial action comparable to PE embedded with AgNO3. Tests by contact and release tests for specific migration of silver from PE composites clearly indicate that, at least in the case of the PE, for composites containing polynuclear silver(I) additives, the antimicrobial action is exerted by contact, without release of silver ions. Moreover, PE composites can be re‐used several times, displaying the same antimicrobial activity. Membrane permeabilization studies and induced reactive oxygen species (ROS) generation tests confirm the disorganization of bacterial cell membranes. The cytotoxic effect, evaluated in CD34+ cells by MTT (3‐(4,5‐dimethylthiazole‐2‐yl)‐2,5‐diphenyltetrazoliumbromide) and CFU (colony forming units) assays, indicates that the PE composites do not induce cytotoxicity in human cells. Studies of ecotoxicity, based on the test of Daphnia magna, confirm tolerability of the PE composites by higher organisms and exclude the release of Ag+ ions in sufficient amounts to affect water environment. 相似文献
607.
Pasquale Longo Ermelinda Siani Stefania Pragliola Guglielmo Monaco 《Journal of polymer science. Part A, Polymer chemistry》2002,40(19):3249-3255
Ethene–propene copolymerizations were performed in the presence of Cs symmetric group 4 metallocenes. The reactivity ratios were strongly influenced by both the transition metal and the ancillary ligands. Substantially alternate, almost random, and blocky copolymers were obtained with titanocene, zirconocene, and hafnocene, respectively, with the bis(dimethylsilyl)‐1,1′‐2,2′‐diyl‐(3′,5′‐diisopropyl)(4‐isopropyl)‐(cyclopentadienyl) ligand, and a blocky copolymer was obtained with (diphenyl methylidene)(cyclopentadienyl)(9‐fluorenyl)TiCl2. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3249–3255, 2002 相似文献
608.
Stefania Bellavia Maria Macconi Benedetta Morini 《Numerical Linear Algebra with Applications》2006,13(10):825-846
An interior point approach for medium and large non‐negative linear least‐squares problems is proposed. Global and locally quadratic convergence is shown even if a degenerate solution is approached. Viable approaches for implementation are discussed and numerical results are provided. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
609.
A Quantitative Relaxometric Version of the ELISA Test for the Measurement of Cell Surface Biomarkers
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Dr. Diego Alberti Dr. Mark van't Erve Dr. Rachele Stefania Dr. Maria Rosaria Ruggiero Dr. Marta Tapparo Dr. Simonetta Geninatti Crich Prof. Silvio Aime 《Angewandte Chemie (International ed. in English)》2014,53(13):3488-3491
Quantitative measurement of marker expression in diseased cells is still a topic of considerable interest and different methodologies are currently under intense scrutiny. This work aims at developing an in vitro diagnostic method based on the release of paramagnetic species from relaxometrically “silent” liposomes operated by the action of a phospholipase A2 (PLA2) previously targeted to the epitope of interest. The released paramagnetic species causes an increase of the longitudinal water proton relaxation rate proportional to the number of PLA2 bound to the cell outer surface. The sensitivity of the herein proposed method, named R‐ELISA, was attempted in the detection of folate receptor expression on human ovarian cancer cells by functionalizing PLA2 with folic acid. Receptor/cell number of 8.3×105 has been measured on IGROV‐1 cells. The R‐ELISA assay can detect nanomolar cell suspension receptor concentrations and has been validated by well‐established spectrofluorimetric procedures. 相似文献
610.
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