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991.
Dr. Sergio Valente Dr. Daniela Trisciuoglio Dr. Maria Tardugno Dr. Rosaria Benedetti Dr. Donatella Labella Prof. Daniela Secci Dr. Ciro Mercurio Dr. Roberto Boggio Dr. Stefano Tomassi Dr. Salvatore Di Maro Prof. Ettore Novellino Prof. Lucia Altucci Dr. Donatella Del Bufalo Prof. Antonello Mai Dr. Sandro Cosconati 《ChemMedChem》2013,8(5):800-811
Herein we report novel pyrrole‐ and benzene‐based hydroxamates ( 8 , 10 ) and 2′‐aminoanilides ( 9 , 11 ) bearing the tert‐butylcarbamate group at the CAP moiety as histone deacetylase (HDAC) inhibitors. Compounds 8 b and 10 c selectively inhibited HDAC6 at the nanomolar level, whereas the other hydroxamates effected an increase in acetyl‐α‐tubulin levels in human acute myeloid leukemia U937 cells. In the same cell line, compounds 8 b and 10 c elicited 18.4 and 21.4 % apoptosis, respectively (SAHA: 16.9 %), and the pyrrole anilide 9 c displayed the highest cytodifferentiating effect (90.9 %). In tests against a wide range of various cancer cell lines to determine its antiproliferative effects, compound 10 c exhibited growth inhibition from sub‐micromolar (neuroblastoma LAN‐5 and SH‐SY5Y cells, chronic myeloid leukemia K562 cells) to low‐micromolar (lung H1299 and A549, colon HCT116 and HT29 cancer cells) concentrations. In HT29 cells, 10 c increased histone H3 acetylation, and decreased the colony‐forming potential of the cancer cells by up to 60 %. 相似文献
992.
Dr. Luca Sancineto Dr. Nunzio Iraci Dr. Serena Massari Dr. Vanessa Attanasio Dr. Gianmarco Corazza Dr. Maria Letizia Barreca Dr. Stefano Sabatini Dr. Giuseppe Manfroni Dr. Nilla Roberta Avanzi Prof. Violetta Cecchetti Prof. Christophe Pannecouque Prof. Alessandro Marcello Dr. Oriana Tabarrini 《ChemMedChem》2013,8(12):1941-1953
993.
994.
Stefano Pastore 《International Journal of Circuit Theory and Applications》2016,44(3):639-659
Real equilibrium solutions of electronic circuits are affected by deviation of real characteristics of devices from their nominal values, producing the displacement of solution points from their nominal position. In this paper, a method to determine all the equilibrium regions in which real equilibrium points may fall is presented. The analysis is based on the introduction of the so‐called strip characteristics that represent the characteristics of devices affected by tolerances. They are modeled by polyhedral characteristics. Different situations may occur as tolerances grow. A nominal solution point may disappear, or on the other end, some solution point not present with nominal characteristics may appear. These possible events call for a classification of the equilibrium regions in either certain or uncertain, depending on the existence or not of an equilibrium point for any choice of real characteristics. The algorithm adopts linear programming techniques and a clustering algorithm. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
995.
The efficiency of epoxy/CNT nanocomposites as photocatalyst on adsorbed, aqueous and gas phases is investigated. Epoxy films containing SWNTs in the range between 0.1 and 0.3 wt% are prepared by means of UV‐induced polymerization and the achieved materials are used as photocatalysts on adsorbed, aqueous, and gas phases. The activity of this new photocatalytic materials is evaluated in the adsorbed state by using the methylene blue target molecule, in the aqueous phase by following the photodegradation of phenol and 3,5‐dichlorophenol, and in the gas phase using nitrogen monoxide as probe molecule. It is demonstrated that the catalyst is suitable for both oxidative and reductive degradation reactions.
996.
Mariafrancesca Fochi Lucia Gramigna Andrea Mazzanti Sara Duce Stefano Fantini Alessandro Palmieri Marino Petrini Luca Bernardi 《Advanced Synthesis \u0026amp; Catalysis》2012,354(7):1373-1380
A catalytic asymmetric addition of nitroalkanes to alkylideneindolenines, generated in situ from arylsulfonylindoles, is presented. Despite the weakness of the non‐covalent H‐bond interactions between catalyst and substrates, the performance of the bifunctional organocatalyst used was found to be essentially unaffected by the polarity of the reaction medium. Nitroalkanes, mostly used in nearly stoichiometric amounts, could thus function both as solvents and reagents, resulting in a truly solvent‐free reaction. The broad substrate scope shown by the present transformation allowed the preparation of some optically active tryptamine precursors that are not accessible through the previous catalytic asymmetric methods. 相似文献
997.
Manerba M Vettraino M Fiume L Di Stefano G Sartini A Giacomini E Buonfiglio R Roberti M Recanatini M 《ChemMedChem》2012,7(2):311-317
One of the most prominent alterations in cancer cells is their strict dependence on the glycolytic pathway for ATP generation. This observation led to the evaluation of glycolysis inhibitors as potential anticancer agents. The inhibition of lactate dehydrogenase (LDH) is a promising way to inhibit tumor cell glucose metabolism without affecting the energetic balance of normal tissues. However, the success of this approach depends chiefly on the availability of inhibitors that display good selectivity. We identified a compound (galloflavin, CAS 568‐80‐9) which, in contrast to other inhibitors of human LDH, hinders both the A and B isoforms of the enzyme. To determine the mechanism of action, we collected LDH‐A and ‐B inhibition data in competition reactions with pyruvate or NADH and evaluated the results using software for enzyme kinetics analysis. We found that galloflavin inhibits both human LDH isoforms by preferentially binding the free enzyme, without competing with the substrate or cofactor. The calculated Ki values for pyruvate were 5.46 μM (LDH‐A) and 15.06 μM (LDH‐B). In cultured tumor cells, galloflavin blocked aerobic glycolysis at micromolar concentrations, did not interfere with cell respiration, and induced cell death by triggering apoptosis. To our knowledge, the inhibition of LDH is, to date, the only biochemical effect described for galloflavin. Because galloflavin is not commercially available, we also describe herein a procedure for its synthesis and report its first full chemical characterization. 相似文献
998.
Giovanna Lomolino Alberto De Iseppi Stefano Bravo Mara Vegro Matteo Marangon Antonella Crapisi Andrea Curioni 《International Journal of Dairy Technology》2023,76(2):418-428
Four milk-based ice cream samples were produced by heating (65°C) the ingredients at different pressures (0.5, 1.0 bar) and times (5, 30 min). Overrun, melting behaviour, particle size, viscosity and sensory analysis were conducted for each time/temperature combination. The 5-min vacuum application resulted in a reduction of overrun and air bubbles size, whereas ice cream viscosity increased. Opposite outcomes were found for the sample treated with vacuum for 30 min, which also showed a significant fat globule size reduction (<3.0 μm). Sensory analysis revealed that the use of vacuum improved sweetness, milky and creamy sensations regardless the treatment times. 相似文献
999.
Fabio Bignotti Stefano Pandini Francesco Baldi Riccardo De Santis 《Polymer Composites》2011,32(7):1034-1048
The curing reaction, structure, and glass transition behavior of epoxy‐clay nanocomposites prepared using several different resin/hardener ratios were investigated. Nonisothermal DSC experiments evidenced that the incorporation of the organoclay did not induce appreciable changes in the curing enthalpy, but determined a slight acceleration of the curing reaction, without modifying the activation energy. TEM and SEM analyses of the nanocomposite resins showed the presence of micrometric aggregates for all the resin/hardener ratios investigated, even though these materials showed good optical clarity and their WAXD analyses did not evidence any organoclay peak. In addition, the higher the hardener content, the lower the tendency toward exfoliation and the broader the distribution of the interlamellar distances. The degree of cross‐linking of cured resins was evaluated both from measurements of the elastic modulus in the rubbery plateau and from solvent sorption experiments. A maximum in cross‐link density was observed near the stoichiometric composition. Both modulus and sorption experiments suggested that filler‐matrix adhesion increased with increasing the resin/hardener ratio, a trend that was confirmed also by glass transition temperature data. An analysis of ethyl acetate sorption curves evidenced that a gradual transition from Fickian to Case II diffusion occurred as the resin/hardener ratio was raised and that the organoclay promoted deviation from the Fickian behavior. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献
1000.
Stefano Pandini Francesco Baldi Riccardo De Santis Fabio Bignotti 《Polymer Composites》2011,32(9):1461-1472
In this work, the effect of the resin/hardener ratio on the small deformation, yield, post‐yield, and fracture behavior of a series of DGEBA‐Jeffamine epoxy‐clay nanocomposites with a fixed organo‐clay content (6 phr), and of the corresponding unfilled resins, was investigated. The mechanical behavior at small deformation was studied by means of uniaxial tensile tests, whereas compression tests were employed to investigate the large (yield and post‐yield) deformation levels. The fracture behavior was studied by the application of fracture mechanics testing methods. The results pointed out that small variations in the resin/hardener ratio used for the preparation of the resin can give rise to remarkable differences in the mechanical behavior at large deformation levels and at fracture. These effects were related to the parameters characteristic of the macromolecular architecture of the resins (chain segments flexibility and crosslink density). The results obtained on nanofilled systems showed that the effect of the resin/hardener ratio on the mechanical behavior of the resins is reduced in presence of organoclay particles. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献