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991.
Identification of Limonol Derivatives as Heat Shock Protein 90 (Hsp90) Inhibitors through a Multidisciplinary Approach
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Dr. Maria G. Chini Dr. Nicola Malafronte Dr. Maria C. Vaccaro Dr. Maria J. Gualtieri Dr. Antonio Vassallo Dr. Michele Vasaturo Prof. Sabrina Castellano Dr. Ciro Milite Prof. Antonietta Leone Prof. Giuseppe Bifulco Prof. Nunziatina De Tommasi Prof. Fabrizio Dal Piaz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(37):13236-13250
The identification of inhibitors of Hsp90 is currently a primary goal in the development of more effective drugs for the treatment of various types of multidrug resistant malignancies. In an attempt to identify new small molecules modulating the activity of Hsp90, we screened a small library of tetranortriterpenes. A high‐affinity interaction with Hsp90 inducible form was uncovered for eight of these compounds, five of which are described here for the first time. By monitoring the ATPase activity and the citrate synthase thermal induced aggregation, compound 1 (cedrelosin A), 3 (7α‐limonylacetate), and 5 (cedrelosin B), containing a limonol moiety, were found to be the most effective in compromising the Hsp90α chaperone activity. Consistent with these findings, the three compounds caused a depletion of c‐Raf and pAkt Hsp90 client proteins in HeLa and MCF/7 cell lines. Induced fit docking protocol and molecular dynamics were used to rationalize the structural basis of the biological activity of the limonol derivatives. Taken together, these results point to limonol‐derivatives as promising scaffolds for the design of novel Hsp90α inhibitors. 相似文献
992.
G. Longo G. Busarello A. Rifatto E. Acampa A. D'Orsi P. Paura C. Sterken 《Il Nuovo Cimento C》1992,15(6):1097-1099
Summary We present a complete database of photoelectric and photographic multiaperture photoelectric photometry of galaxies. The database
contains all data published prior to 1991, in all standard photometric bands from UV to IR. The database contains also some
global quantities as, for instance, total magnitudes and color indexes.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
993.
AKi is a complete subgraph of size i. A Ki-cover of a graph G(V, E) is a set C of Ki?1s of G such that every Ki in G contains at least one Ki?1 in C . ci(G) is the cardinality of a smallest Ki-cover of G. A Ki-packing of G is a set of Kis such that no two Kis have i ? 1 nodes in common. pi(G) is the cardinality of a largest Ki-packing of G. Let F i(G) denote the set of Kis in G and define ci(F) and pi(F) analogously for F ? F i(G). G is Ki-perfect if ?F ? F i(G), ci(F) = pi(F). The K2-perfect graphs are precisely the bipartite graphs. We present a characterization of Ki-perfect graphs that is similar to the Strong Perfect Graph Conjecture, and explore the relationships between Ki-perfect graphs and normal hypergraphs. Furthermore, if iA denotes the 0 ? 1 matrix of G where the rows are the elements of F i?1(G) that belong to at least one Ki and the columns are the elements of F i(G), then we show that iA is perfect iff G is a Ki-perfect graph. We also characterize the Ki-perfect graphs for which iAis balanced. 相似文献
994.
995.
Gianfranco L. Cariolaro Roberto Corvaja Pierluigi Franco Michele Midrio Gianfranco L. Pierobon 《Fiber and Integrated Optics》1994,13(2):199-213
This article presents an application of a recently published probablistic model for traveling wave optical amplification. Both optical signal and amplified spontaneous emission (ASE) noise are modeled as bunches of photons traveling along the amplifying region with size varying according to simple random rules. The results of the theory enable one to obtain a complete and accurate characterization of the signal and noise counting at the amplifier output. On the basis of the above statistics, we find a realistic evaluation of the limits imposed by both quantum and ASE noise on the performances of a receiver including an optical amplifier at a preamplifier stage. 相似文献
996.
997.
Cosimo Carfagna Michele Vacatello Paolo Corradini 《Journal of polymer science. Part A, Polymer chemistry》1977,15(1):1-4
The melting behavior of diamides of general formula (n-CpH2p+1)CONH(CH2)qNHCO(nCpH2p+1) has been investigated by differential scanning calorimetry (DSC). The close similarity of the melting behavior of these low molar mass compounds with that of polymeric amides is discussed in terms of restricted conformational disorder in the amorphous state, due to the high degree of retention of hydrogen bonding. 相似文献
998.
999.
Giafranco Cainelli Michele Contento Daria Giacomini Mauro Panunzio 《Tetrahedron letters》1985,26(7):937-940
A total stereocontrolled synthesis of (), an intermediate in the synthesis of (+)-thienamycin, carbapenems and penems, based on a strategy that uses the S(-)hydroxy ethylbutyrate as chiral building block, is reported. 相似文献
1000.
L.F. Liotta A. Macaluso G. Pantaleo A. Longo A. Martorana G. Deganello G. Marcì S. Gialanella 《Journal of Sol-Gel Science and Technology》2003,26(1-3):235-240
Ceria-zirconia mixed oxides of nominal composition Ce0.6Zr0.4O2 were prepared by sol-gel method. The structural and morphological modifications of these materials due to calcination and redox treatments up to 1000°C were studied by X-ray diffraction (XRD) and Rietveld refinements, specific surface area measurements (BET), oxygen storage capacity (OSC), TEM and SEM analyses. The materials maintain high OSC after several hours of treatments at 1000°C in oxidizing and reducing atmosphere, showing good resistance to the thermal ageing. An improvement of the OSC is manifested after repetitive redox cycles, even though textural characterization shows that reduction/oxidation processes induce sintering of the crystallites. 相似文献