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81.
Natalia Calonghi Carla Boga Patrizia Nitti Dario Telese Silvia Bordoni Giovanna Farruggia Fioretta Asaro Martina Grandi Chiara Zalambani Gabriele Micheletti 《Molecules (Basel, Switzerland)》2022,27(8)
A series of regioisomers of the hydroxystearic acid (HSA) was prepared, and the effect of the position of the hydroxyl group along the chain on a panel of human cancer cell lines was investigated. Among the various regioisomers, those carrying the hydroxyl at positions 5, 7, and 9 had growth inhibitor activity against various human tumor cell lines, including CaCo-2, HT29, HeLa, MCF7, PC3, and NLF cells. 10-HSA and 11-HSA showed a very weak effect. 8-HSA did not show inhibitory activity in all cell lines. The biological role of 7-HSA and 9-HSA is widely recognized, while little is known about the effects of 5-HSA. Therefore, the biological effects of 5-HSA in HeLa, HT29, MCF7, and NLF cell lines were investigated using the Livecyte’s ptychography technology, which allows correlating changes in proliferation, motility, and morphology as a function of treatment at the same time. 5-HSA not only reduces cell proliferation but also induces changes in cell displacement, directionality, and speed. It is important to characterize the biological effects of 5-HSA, this molecule being an important component of fatty acyl esters of hydroxy fatty acids (FAHFA), a class of endogenous mammalian lipids with noticeable anti-diabetic and anti-inflammatory effects. 相似文献
82.
Paolo Ferruti Elisabetta Ranucci Amedea Manfredi Nicolò Mauro Elena Ferrari Riccardo Bruni Francesco Colombo Patrizia Mussini Manuela Rossi 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):5000-5010
Traditional precipitation methods for inorganic micropollutant removal from waters are increasingly being replaced by sorption methods based on both natural and synthetic materials. In this context, two novel effective heavy metal ions absorbers are presented. These resins, LYMA and LMT85, were crosslinked poly(amidoamine)s carrying amine and carboxyl groups in their repeating units. In particular, the LYMA‐repeating unit contains one carboxyl and two amine groups and is a mimic of L ‐lysine, whereas LMT85 contains two amine and five carboxyl groups and is a mimic of EDTA. Both resins were prepared at moderate cost by simple eco‐friendly procedures. The heavy metal ion set adopted as benchmark was Cu2+, Cd2+, Pb2+, Zn2+, Ni2+, and Co2+. LYMA proved selective for Cu2+ and Ni2+, the other ions tested being negligibly absorbed, whereas LMT85 proved capable of rapidly and quantitatively absorbing all the ions tested either singly or in mixed solution. The absorption process was reversible, and the resins were easily regenerated by acidification. The absorption of several metal ions imparted intense coloring to the resins, a feature possibly exploitable for analytical purposes. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
83.
L. Biasetto M. Manzolaro A. Andrighetto G. Meneghetti S. Carturan P. Zanonato P. Colombo G. Prete 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):517-521
The target is one of the key issues of isotope separation on line (ISOL) facilities. SPES, now under development at LNL-INFN,
is an innovative ISOL facility possessing a target chatacterized by seven separate uranium dicarbide thin disks. The research
on the materials development and target prototyping is discussed in the following. 相似文献
84.
Chiara Capolungo Dr. Damiano Genovese Prof. Marco Montalti Prof. Enrico Rampazzo Prof. Nelsi Zaccheroni Prof. Luca Prodi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17529-17541
The growing numbers related to plastic pollution are impressive, with ca. 70 % of produced plastic (>350 tonnes/year) being indiscriminately wasted in the environment. The most dangerous forms of plastic pollution for biota and human health are micro- and nano-plastics (MNPs), which are ubiquitous and more bioavailable. Their elimination is extremely difficult, but the first challenge is their detection since existing protocols are unsatisfactory for microplastics and mostly absent for nanoplastics. After a discussion of the state of the art for MNPs detection, we specifically revise the techniques based on photoluminescence that represent very promising solutions for this problem. In this context, Nile Red staining is the most used strategy and we show here its pros and limitations, but we also discuss other more recent approaches, such as the use of fluorogenic probes based on perylene-bisimide and on fluorogenic hyaluronan nanogels, with the added values of biocompatibility and water solubility. 相似文献
85.
Federico Colombo Luigi Lentini Terenziano Raparelli Vladimir Viktorov 《Meccanica》2017,52(15):3645-3660
Active compensation is an effective method for increasing air bearing static and dynamic performance. This paper describes the design, modelling and experimental validation of an actively compensated externally pressurized gas bearing. The active compensation is obtained through the support compensation strategy. With this strategy, the system’s initial working position is restored by compensating for air gap variations through adjustments to the bearing vertical dimension. The described bearing consists in a conventional thrust bearing which is integrated with a multilayer piezoelectric actuator, a compliant mechanism and a digital controller. Nevertheless the non-linear nature of the air system, a simple linear model results to be an effective choice for neighbour of equilibrium conditions. Results demonstrate the good accuracy of the model and the system’s good capacity of rejecting external force disturbances. 相似文献
86.
Sorin‐Claudiu Roşca Dr. Chiara Dinoi Dr. Elsa Caytan Dr. Vincent Dorcet Prof. Dr. Michel Etienne Prof. Dr. Jean‐François Carpentier Dr. Yann Sarazin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6505-6509
Strontium and calcium (alkaline earth: Ae) olefin complexes stabilised by secondary Ae???F?C and β‐agostic Ae???H?Si interactions are presented. Olefin coordination onto the alkaline earths is plain in the solid state, and it is thermodynamically favoured over the coordination of THF. The existence of the Ae???olefin interactions is corroborated by solution NMR data and DFT computations. The coordination mode of the olefin varies with steric effects and, if enforced, olefin dissociation can be compensated by the other non‐covalent interactions, as supported by DFT computations. 相似文献
87.
Cocchi M Franchini G Manfredini M Marchetti A Pigani L Seeber R Tassi L Ulrici A Vignali M Zanardi C Zannini P 《Annali di chimica》2002,92(3):177-185
A study on polythiophene coated microelectrodes is reported, the goal being that of checking the capability of these electrochemical systems to work in low conductive media. The possibility of electrochemically p-doping the polymer in the presence of very low concentrations or even in the absence of supporting electrolyte in the solution is ascertained, opening the way to the use of similar systems in pure solvent media. This result is obtained in such conditions that the presence of residual charges--and corresponding counterions--trapped inside the film coating can be reasonably hypothesised. 相似文献
88.
Bolm C Palazzi C Franciò G Leitner W 《Chemical communications (Cambridge, England)》2002,(15):1588-1589
The aerobic Baeyer-Villiger oxidation of a wide range of ketones, both cyclic and acyclic to the corresponding esters or lactones can be efficiently carried out in compressed carbon dioxide in the presence of an aldehyde as co-reductant. 相似文献
89.
90.