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991.
Rosaria Ottan Paolo Paoli Mario Cappiello Trung Ngoc Nguyen Ilenia Adornato Antonella Del Corso Massimo Genovese Ilaria Nesi Roberta Moschini Alexandra Naß Gerhard Wolber Rosanna Maccari 《Molecules (Basel, Switzerland)》2021,26(2)
Diabetes mellitus (DM) is a complex disease which currently affects more than 460 million people and is one of the leading cause of death worldwide. Its development implies numerous metabolic dysfunctions and the onset of hyperglycaemia-induced chronic complications. Multiple ligands can be rationally designed for the treatment of multifactorial diseases, such as DM, with the precise aim of simultaneously controlling multiple pathogenic mechanisms related to the disease and providing a more effective and safer therapeutic treatment compared to combinations of selective drugs. Starting from our previous findings that highlighted the possibility to target both aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two enzymes strictly implicated in the development of DM and its complications, we synthesised 3-(5-arylidene-4-oxothiazolidin-3-yl)propanoic acids and analogous 2-butenoic acid derivatives, with the aim of balancing the effectiveness of dual AR/PTP1B inhibitors which we had identified as designed multiple ligands (DMLs). Out of the tested compounds, 4f exhibited well-balanced AR/PTP1B inhibitory effects at low micromolar concentrations, along with interesting insulin-sensitizing activity in murine C2C12 cell cultures. The SARs here highlighted along with their rationalization by in silico docking experiments into both target enzymes provide further insights into this class of inhibitors for their development as potential DML antidiabetic candidates. 相似文献
992.
Lanthanoid/Alkali Metal β‐Triketonate Assemblies: A Robust Platform for Efficient NIR Emitters 下载免费PDF全文
Brodie L. Reid Dr. Stefano Stagni Dr. Joanna M. Malicka Dr. Massimo Cocchi Dr. Alexandre N. Sobolev Prof. Brian W. Skelton Dr. Evan G. Moore Prof. Garry S. Hanan Prof. Mark I. Ogden Dr. Massimiliano Massi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18354-18363
The reaction of hydrated lanthanoid chlorides with tribenzoylmethane and an alkali metal hydroxide consistently resulted in the crystallization of neutral tetranuclear assemblies with the general formula [Ln(Ae ? HOEt)( L )4]2 (Ln=Eu3+, Er3+, Yb3+; Ae=Na+, K+, Rb+). Analysis of the crystal structures of these species revealed a coordination geometry that varied from a slightly distorted square antiprism to a slightly distorted triangular dodecahedron, with the specific geometrical shape being dependent on the degree of lattice solvation and identity of the alkali metal. The near‐infrared (NIR)‐emitting assemblies of Yb3+ and Er3+ showed remarkably efficient emission, characterized by significantly longer excited‐state lifetimes (τobs≈37–47 μs for Yb3+ and τobs≈4–6 μs for Er3+) when compared with the broader family of lanthanoid β‐diketonate species, even in the case of perfluorination of the ligands. The Eu3+ assemblies show bright red emission and a luminescence performance (τobs≈0.5 ms, ${{\Phi}{{{\rm L}\hfill \atop {\rm Ln}\hfill}}}$ ≈35–37 %, ηsens≈68–70 %) more akin to the β‐diketonate species. The results highlight that the β‐triketonate ligand offers a tunable and facile system for the preparation of efficient NIR emitters without the need for more complicated perfluorination or deuteration synthetic strategies. 相似文献
993.
Cesare Oliviero Rossi Carmen Cretu Loredana Ricciardi Angela Candreva Massimo La Deda Iolinda Aiello 《Liquid crystals》2017,44(5):880-888
Luminescent complexes with general formula [(C^N)2Ir(N^N)]OCOCH3, where C^N = 2-phenylpyridine (ppy) and N^N = 2,2?-bipyridine (bpy), self-assemble into ordered ‘soft’ viscous mesophases of chromonic type. By changing the ancillary ligand with 1,10-phenanthroline (phen), a new mesomorphic complex was obtained. The self-assembly into ordered liquid crystalline phases of chromonic type in water was investigated by comprehensive rheological and photophysical studies. By changing the ancillary ligand bpy with phen, assembly into smaller, more symetric aggregates is favoured, resulting in lower viscosity and more dynamic mesophase. 相似文献
994.
Modulation of ionization and structural properties of weak polyelectrolytes due to 1D, 2D,and 3D confinement 下载免费PDF全文
What is the impact of reducing the space available to molecules onto their properties is a fundamental question for capillary systems, molecular biology and transport, protein and material sciences. Possibly influenced by space restriction, ionization degree has rarely been studied for confined polyelectrolytes; Monte Carlo titrations and coarse‐grained models are thus used to investigate structural and ionization changes induced on a single polyelectrolyte chain by confinement into slit (1D), cylindrical (2D), or spherical (3D) cavities. Four polyelectrolyte models differing in chain stiffness and the possible formation of charged hydrogen bonds (c? H? bonds) are studied. Low pH effective ionization constants (pKa ) of confined chains are lower than for the free species if c? H? bonds can be formed. This is especially evident for 3D‐confined stiff chains, a finding rationalized by the impact of global compression onto chain conformations. If no c? H? bonds are allowed, chain ionization is largely unaffected by 1D or 2D confinement, while it is depressed by 3D. Chain confinement Helmholtz energy (ΔA conf) was computed as a function of both pH and confining width (W) to gauge the impact of ionization‐induced stiffening onto ΔA conf versus W behavior, the partition coefficient governing absorption, and the average number of c? H? bond formed. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 1088–1102 相似文献
995.
Mattia Bongini Massimo Fornasier Francesco Rossi Francesco Solombrino 《Journal of Optimization Theory and Applications》2017,174(1):1-4
This paper provides a characterization of the optimal average cost function, when the long-run (risk-sensitive) average cost criterion is used. The Markov control model has a denumerable state space with finite set of actions, and the characterization presented is given in terms of a system of local Poisson equations, which gives as a by-product the existence of an optimal stationary policy. 相似文献
996.
Fragment‐Based Discovery of a Dual pan‐RET/VEGFR2 Kinase Inhibitor Optimized for Single‐Agent Polypharmacology 下载免费PDF全文
Brendan Frett Francesca Carlomagno Maria Luisa Moccia Annalisa Brescia Giorgia Federico Valentina De Falco Brittany Admire Zhongzhu Chen Wenqing Qi Massimo Santoro Hong‐yu Li 《Angewandte Chemie (International ed. in English)》2015,54(30):8717-8721
Oncogenic conversion of the RET (rearranged during transfection) tyrosine kinase is associated with several cancers. A fragment‐based chemical screen led to the identification of a novel RET inhibitor, Pz‐1. Modeling and kinetic analysis identified Pz‐1 as a type II tyrosine kinase inhibitor that is able to bind the “DFG‐out” conformation of the kinase. Importantly, from a single‐agent polypharmacology standpoint, Pz‐1 was shown to be active on VEGFR2, which can block the blood supply required for RET‐stimulated growth. In cell‐based assays, 1.0 nM of Pz‐1 strongly inhibited phosphorylation of all tested RET oncoproteins. At 1.0 mg kg?1 day?1 per os, Pz‐1 abrogated the formation of tumors induced by RET‐mutant fibroblasts and blocked the phosphorylation of both RET and VEGFR2 in tumor tissue. Pz‐1 featured no detectable toxicity at concentrations of up to 100.0 mg kg?1, which indicates a large therapeutic window. This study validates the effectiveness and usefulness of a medicinal chemistry/polypharmacology approach to obtain an inhibitor capable of targeting multiple oncogenic pathways. 相似文献
997.
Massimo Cicognani Ferruccio Colombini 《Journal of Mathematical Analysis and Applications》2007,333(2):1237-1253
In the strictly hyperbolic Cauchy problem, we investigate the relation between the modulus of continuity in the time variable of the coefficients and the well-posedness in Beurling-Roumieu classes of ultradifferentiable functions and functionals. We find well-posedness in nonquasianalytic classes assuming that the coefficients have modulus of continuity tω(1/t) such that . This condition is sharp because, in the case , we provide examples of Cauchy problems which are well-posed only in quasianalytic classes. 相似文献
998.
We consider the Cauchy problem for the Perona–Malik equation
in a bounded open set , with Neumann boundary conditions.
If n = 1, we prove some a priori estimates on u and u
x
. Then we consider the semi-discrete scheme obtained by replacing the space derivatives by finite differences. Extending the
previous estimates to the discrete setting we prove a compactness result for this scheme and we characterize the possible
limits in some cases. Finally, for n > 1 we give examples to show that the corresponding estimates on are in general false. 相似文献
999.
Pier Domenico Lamberti Massimo Lanza de Cristoforis 《Mediterranean Journal of Mathematics》2007,4(4):435-449
Let Ω be an open connected subset of for which the imbedding of the Sobolev space W
1,2(Ω) into the space L
2(Ω) is compact. We consider the Neumann eigenvalue problem for the Laplace operator in the open subset (Ω) of , where is a Lipschitz continuous homeomorphism of Ω onto (Ω). Then we prove a result of real analytic dependence for symmetric functions of the eigenvalues upon variation of .
This paper represents an extension of a part of the work performed by P.D. Lamberti in his PhD Thesis at the University of
Padova under the guidance of M. Lanza de Cristoforis. 相似文献
1000.