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91.
In this paper, we present an experimental setup to study photoionization of atoms and molecules using the high-order harmonic radiation generated by a highly non-linear process. We report on the characteristics of this table-top experimental apparatus showing also the results of the photoionization of krypton gas, by the use of the ninth order harmonic of fs Ti : S laser, observed both in the electron spectrum and in the mass spectrum. 相似文献
92.
Alessandro Venditti Claudio Frezza Fabio Sciubba Sebastiano Foddai Mauro Serafini Marcello Nicoletti 《Natural product research》2016,30(15):1698-1705
We compared the respective metabolite patterns of two Pedicularis species from Dolomites. Seven phenylethanoid glycosides, i.e., verbascoside (1), echinacoside (2), angoroside A (3), cistantubuloside B1 (4), wiedemannioside C (5), campneoside II (11) and cistantubuloside C1 (12), together with several iridoid glucosides as aucubin (6), euphroside (7), monomelittoside (8), mussaenosidic acid (9) and 8-epiloganic acid (13) were identified. Pedicularis verticillata showed also the presence of greatly unexpected secoiridoids, ligustroside (14) and excelside B (15), very rare compounds in Lamiales. Both PhGs and iridoids are considered of taxonomical relevance in the Asteridae and their occurrence in Pedicularis was discussed. In particular, the exclusive presence of several compounds such as 8-epiloganic acid (13), campneoside II (11), cistantubuloside C1 (12), ligustroside (14) and excelside B (15) in Pedicularis rostratocapitata, and angoroside A (3), cistantubuloside B1 (4) and wiedemannioside C (5) in P. verticillata could be considered specific markers for the two botanical entities. 相似文献
93.
Activation of Hsp90 Enzymatic Activity and Conformational Dynamics through Rationally Designed Allosteric Ligands
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Dr. Sara Sattin Dr. Jiahui Tao Dr. Gerolamo Vettoretti Dr. Elisabetta Moroni Dr. Marzia Pennati Dr. Alessia Lopergolo Dr. Laura Morelli Dr. Antonella Bugatti Dr. Abbey Zuehlke Dr. Mike Moses Dr. Thomas Prince Dr. Toshiki Kijima Dr. Kristin Beebe Dr. Marco Rusnati Dr. Len Neckers Dr. Nadia Zaffaroni Prof. David A. Agard Prof. Anna Bernardi Dr. Giorgio Colombo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(39):13598-13608
Hsp90 is a molecular chaperone of pivotal importance for multiple cell pathways. ATP‐regulated internal dynamics are critical for its function and current pharmacological approaches block the chaperone with ATP‐competitive inhibitors. Herein, a general approach to perturb Hsp90 through design of new allosteric ligands aimed at modulating its functional dynamics is proposed. Based on the characterization of a first set of 2‐phenylbenzofurans showing stimulatory effects on Hsp90 ATPase and conformational dynamics, new ligands were developed that activate Hsp90 by targeting an allosteric site, located 65 Å from the active site. Specifically, analysis of protein responses to first‐generation activators was exploited to guide the design of novel derivatives with improved ability to stimulate ATP hydrolysis. The molecules’ effects on Hsp90 enzymatic, conformational, co‐chaperone and client‐binding properties were characterized through biochemical, biophysical and cellular approaches. These designed probes act as allosteric activators of the chaperone and affect the viability of cancer cell lines for which proper functioning of Hsp90 is necessary. 相似文献
94.
Sugata Barui Marzia Conte Nicolò Maria Percivalle Rocío María García Montero Luisa Racca Marco Allione Valentina Cauda 《Particle & Particle Systems Characterization》2023,40(4):2200138
This study focuses on the development of theranostic, dual drug-loaded nanocarriers to propose a proof-of-principle therapeutic approach in the treatment of pancreatic ductal adenocarcinoma (PDAC). The nanoconstructs consist of a core of zinc oxide nanocrystals doped with gadolinium, useful as a potential contrast agent in magnetic resonance imaging applications. After functionalizing their surface with amino-propyl groups, the physical adsorption of two hydrophobic drugs is performed: Vismodegib and Sorafenib. Their synergistic use might improve PDAC treatment and stroma depletion when co-delivered in the tumor microenvironment for future in vivo applications. To enhance the nanoconstructs’ biostability, the ensemble is coated by a lipid bilayer and a tumor targeting peptide is incorporated on the outer shell surface. As a first proof of concept, the resulting nanoconstructs are tested against two pancreatic cancer cell lines, showing a modest increase in treatment efficacy compared to the free drug counterparts and proving to spare healthy pancreatic cells. In a second testing set, the dual-drug loaded nanoconstructs are tested on both cell lines previously sensitized to a first-line chemotherapeutic drug, Gemcitabine, showing an improved treatment response. From these preliminary results, the nanotheranostic platforms might constitute a good starting point for future PDAC therapy and diagnosis studies. 相似文献
95.
Lidia Leporini Luigi Menghini Marzia Foddai Giacomo Luigi Petretto Mario Chessa Bruno Tirillini 《Natural product research》2015,29(10):899-907
Ethanol extracts of Stachys glutinosa L. (Lamiaceae) were investigated for antioxidative properties, as well as antiproliferative action on various cell lines. The antioxidant activities were investigated by ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulphonic acid) assay, DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, β-carotene/linoleic acid assay, scavenging of hydrogen peroxide (horseradish peroxidase test), superoxide anion scavenging, and hypochlorous acid scavenging (taurine test). The antioxidant activity was reported as IC50 and reveals antioxidant effects. Antiproliferative effects were measured in vitro on three cell lines: HepG2 (human hepatocarcinoma), MCF7 (breast human adenocarcinoma) and C2C12 (mouse myoblast) cell lines by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The ethanol extract induced variations in cell viability on all cell lines tested. At 200 μg/mL, the effects on cell viability were ? 23%, ? 27% and ? 37%, respectively, for C2C12, MCF7 and HepG2. 相似文献
96.
Alessandra Vitale Marzia Quaglio Stefano Turri Matteo Cocuzza Roberta Bongiovanni 《先进技术聚合物》2013,24(12):1068-1074
Herein, we describe the preparation and characterization of a material suitable for the fabrication of microfluidic devices. The material is a silicone acrylic polymer, obtained by photopolymerization. It is polymerase chain reaction (PCR) compatible, resistant to temperature, optically transparent, and dimensionally stable; it has a better water and solvent resistance if compared with polydimethylsiloxane. Production of microfluidic layouts is successfully tested: a simple photolithographic approach allows to accurately control the pattern transfer and to produce PCR compatible microfluidic devices. The polymer characterization suggests that the proposed material satisfies all the characteristics required for an ideal PCR chip, without further treatment. Moreover, the possibility for fast, accurate, and cheap reproducibility of microdevices by liquid phase photopolymerization increases the polymer attractiveness. The material is a good alternative with respect to polydimethylsiloxane for the fabrication of microfluidic chips for biological analysis purposes. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
97.
98.
Received September 18, 2001 / Published online February 28, 2002 相似文献
99.
Ali Al-Marzouqi Baboucarr Jobe Giovanna Corti Marzia Cirri Paola Mura 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):223-231
The objective of this study was to investigate the effectiveness of supercritical carbon dioxide (SC CO2) technique for preparing solid complexes between β-cyclodextrin and three local anesthetic agents (benzocaine, bupivacaine, and mepivacaine) by comparing it to more traditional
methods such as kneading, co-evaporation, co-grinding, and sealed-heating. Effects of variation of experimental conditions,
i.e. temperature, pressure and exposure time, on the products prepared by SC CO2 method were also examined. The products obtained were characterized by powder X-ray diffractometry and Fourier transform
infrared spectroscopy, and tested for dissolution properties. Results suggested the possibility of complex formation between
β-cyclodextrin and the three anesthetic agents, and indicated that it was influenced by the preparation technique. The co-grinding
method was the only one resulting in completely amorphous products for all three drugs. Almost amorphous products, with only
limited residual crystallinity, were obtained by co-evaporation and kneading techniques, while SC CO2 and sealed-heating methods gave rise to more crystalline systems. As for the SC CO2 method, temperature (for benzocaine and bupivacaine) or exposure time (for mepivacaine) had significant effects on the solid-state
properties of the final products. Dissolution studies indicated that all the examined methods were more effective than the
simple physical mixing in improving drug dissolution properties, but the different rank orders observed for the different
drugs suggested that there is no general rule for the selection of the most effective preparation method, which depends on
the type of drug-Cyd system considered. Nevertheless, in all cases, products obtained by the SC CO2 method showed satisfactory dissolution properties. 相似文献
100.
The reaction between tert-butylmagnesium chloride (or tert-pentylmagnesium chloride) and the particular phosphorus-sulfur bond of a benzothiadiphospholic system showed, for the first time, evidence of formation of intermediates with a four-center structure. The possibility, for the phosphorus atom, to have very stable hypervalent coordinations makes it possible to observe its hypervalent states during the course of a reaction. The benzothiadiphosphole, with its bicyclic folded structure, further stabilizes the hypervalent coordinations thus making the intermediates sufficiently stable to be detected during the course of the reaction by 31P NMR spectroscopy, which revealed the nature and the stability of the species involved in this reaction, carried out also using other Grignard reagents. 相似文献