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排序方式: 共有675条查询结果,搜索用时 203 毫秒
1.
Bokyung Kim Young Ho Ko Massimiliano Runfola Simona Rapposelli Gabriella Ortore Grazia Chiellini Jin Hae Kim 《International journal of molecular sciences》2021,22(7)
Thyromimetics, whose physicochemical characteristics are analog to thyroid hormones (THs) and their derivatives, are promising candidates as novel therapeutics for neurodegenerative and metabolic pathologies. In particular, sobetirome (GC-1), one of the initial halogen-free thyromimetics, and newly synthesized IS25 and TG68, with optimized ADME-Tox profile, have recently attracted attention owing to their superior therapeutic benefits, selectivity, and enhanced permeability. Here, we further explored the functional capabilities of these thyromimetics to inhibit transthyretin (TTR) amyloidosis. TTR is a homotetrameric transporter protein for THs, yet it is also responsible for severe amyloid fibril formation, which is facilitated by tetramer dissociation into non-native monomers. By combining nuclear magnetic resonance (NMR) spectroscopy, computational simulation, and biochemical assays, we found that GC-1 and newly designed diphenyl-methane-based thyromimetics, namely IS25 and TG68, are TTR stabilizers and efficient suppressors of TTR aggregation. Based on these observations, we propose the novel potential of thyromimetics as a multi-functional therapeutic molecule for TTR-related pathologies, including neurodegenerative diseases. 相似文献
2.
Veronica Cocetta Vincenzo Quagliariello Francesco Fiorica Massimiliano Berretta Monica Montopoli 《International journal of molecular sciences》2021,22(4)
Resistance to chemotherapy still remains a major challenge in the clinic, impairing the quality of life and survival rate of patients. The identification of unconventional chemosensitizing agents is therefore an interesting aspect of cancer research. Resveratrol has emerged in the last decades as a fascinating molecule, able to modulate several cancer-related molecular mechanisms, suggesting a possible application as an adjuvant in cancer management. This review goes deep into the existing literature concerning the possible chemosensitizing effect of resveratrol associated with the most conventional chemotherapeutic drugs. Despite the promising effects observed in different cancer types in in vitro studies, the clinical translation still presents strong limitations due to the low bioavailability of resveratrol. Recently, efforts have been moved in the field of drug delivery to identifying possible strategies/formulations useful for a more effective administration. Despite the necessity of a huge implementation in this research area, resveratrol appears as a promising molecule able to sensitize resistant tumors to drugs, suggesting its potential use in therapy-refractory cancer patients. 相似文献
3.
4.
Filippo Lococo Massimiliano Paci Cristian Rapicetta Teresa Rossi Valentina Sancisi Luca Braglia Silvio Cavuto Alessandra Bisagni Italia Bongarzone Douglas M. Noonan Adriana Albini Sally Maramotti 《International journal of molecular sciences》2015,16(8):19612-19630
Assessment of biological diagnostic factors providing clinically-relevant information to guide physician decision-making are still needed for diseases with poor outcomes, such as non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) is a promising molecule in the clinical management of NSCLC. While the EGFR transmembrane form has been extensively investigated in large clinical trials, the soluble, circulating EGFR isoform (sEGFR), which may have a potential clinical use, has rarely been considered. This study investigates the use of sEGFR as a potential diagnostic biomarker for NSCLC and also characterizes the biological function of sEGFR to clarify the molecular mechanisms involved in the course of action of this protein. Plasma sEGFR levels from a heterogeneous cohort of 37 non-advanced NSCLC patients and 54 healthy subjects were analyzed by using an enzyme-linked immunosorbent assay. The biological function of sEGFR was analyzed in vitro using NSCLC cell lines, investigating effects on cell proliferation and migration. We found that plasma sEGFR was significantly decreased in the NSCLC patient group as compared to the control group (median value: 48.6 vs. 55.6 ng/mL respectively; p = 0.0002). Moreover, we demonstrated that sEGFR inhibits growth and migration of NSCLC cells in vitro through molecular mechanisms that included perturbation of EGF/EGFR cell signaling and holoreceptor internalization. These data show that sEGFR is a potential circulating biomarker with a physiological protective role, providing a first approach to the functional role of the soluble isoform of EGFR. However, the impact of these data on daily clinical practice needs to be further investigated in larger prospective studies. 相似文献
5.
Massimiliano Corsini Elisa Drelie Gelasca Touradj Ebrahimi Mauro Barni 《Multimedia, IEEE Transactions on》2007,9(2):247-256
This paper addresses the problem of assessing distortions produced by watermarking 3D meshes. In particular, a new methodology for subjective evaluation of the quality of 3D objects is proposed and implemented. Two objective metrics derived from measures of surface roughness are then proposed and their efficiency to predict the perceptual impact of 3D watermarking is assessed and compared with the state of the art. Results obtained show good correlations between the proposed objective metrics and subjective assessments by human observers 相似文献
6.
Innocenzo Muzzalupo Massimiliano Pellegrino Enzo Perri 《European Food Research and Technology》2007,224(4):469-475
Characterization of genetic identity using DNA extracted from olive oil has the potential to facilitate assessment of origin
and varietal conformity. Such a prospect is particularly interesting in light of the increased regional spread of olive cultivars
and their various contributions to olive oil mixtures for certification of denomination of origin. Towards this goal, we have
devised a reliable method for extracting DNA from virgin olive oil that was utilized on monovariety oils from the single,
self-sterile cultivar ‘Ogliarola salentina’. We show that DNA purified from oil can be used for microsatellite analysis and
that the profile of DNA purified from a monovariety oil corresponds to the profile of DNA purified from the leaves of the
same cultivar. While DNA from the pollinators present in the genome of the seed embryo, could potentially contain alleles
not present in the genome fruit pulp, invalidating the molecular traceability of olive oil, we show for the first time that
there is no contamination of seed embryo DNA in a monovariety oil. Thus, this molecular assay is applicable for monovariety
olive oils. 相似文献
7.
We investigate the wave propagation properties of nonuniform plane waves in an (unbounded homogeneous) anisotropic conducting material. Such waves (for which amplitudes vary across surfaces of constant phase) characterize the refracted field in an imperfect dielectric, like the earth when a uniform electromagnetic plane wave is incident from the air. The results, presented in terms of polar diagrams of the attenuation, slowness, energy velocity, and quality factor predict the existence of “stopbands” beyond a given degree of nonuniformity (i.e., combinations of propagation and attenuation directions where there is no wave propagation). This is a peculiar, effect due to the joint presence of anisotropy and conductivity that may have application in the design of synthetic materials acting as absorbers of electromagnetic radiation 相似文献
8.
Foutse Khomh Massimiliano Di Penta Yann-Ga?l Guéhéneuc Giuliano Antoniol 《Empirical Software Engineering》2012,17(3):243-275
Antipatterns are poor design choices that are conjectured to make object-oriented systems harder to maintain. We investigate
the impact of antipatterns on classes in object-oriented systems by studying the relation between the presence of antipatterns
and the change- and fault-proneness of the classes. We detect 13 antipatterns in 54 releases of ArgoUML, Eclipse, Mylyn, and
Rhino, and analyse (1) to what extent classes participating in antipatterns have higher odds to change or to be subject to
fault-fixing than other classes, (2) to what extent these odds (if higher) are due to the sizes of the classes or to the presence
of antipatterns, and (3) what kinds of changes affect classes participating in antipatterns. We show that, in almost all releases
of the four systems, classes participating in antipatterns are more change-and fault-prone than others. We also show that
size alone cannot explain the higher odds of classes with antipatterns to underwent a (fault-fixing) change than other classes.
Finally, we show that structural changes affect more classes with antipatterns than others. We provide qualitative explanations
of the increase of change- and fault-proneness in classes participating in antipatterns using release notes and bug reports.
The obtained results justify a posteriori previous work on the specification and detection of antipatterns and could help
to better focus quality assurance and testing activities. 相似文献
9.
Layered double hydroxides/epoxy (LDHs/EP) nanocomposites were prepared from organo-modified LDHs, a diglycidyl ether of bisphenol A monomer (DGEBA) and amine curing agents. The organo-modified LDHs were obtained by ionic exchange of a magnesium-aluminum carbonate LDH in an acid medium. X-ray diffraction and transmission electron microscopy showed a dispersion of the layers at a nanometer scale, indicating the formation of LDH/EP nanocomposites. The thermal degradation and flame resistance properties of LDH/EP nanocomposites, montmorillonite-epoxy (MMT/EP) nanocomposites, LDH/EP microcomposites and aluminum hydroxide-epoxy microcomposites were compared by thermogravimetrical analyses, simultaneous thermal analyses, UL94 and cone calorimeter tests. Only LDH/EP nanocomposites showed self-extinguishing behavior in the horizontal UL94 test; LDH/EP microcomposites and MMT/EP nanocomposites samples burned completely showing that the unique flame resistance of LDH/EP nanocomposites is related to both the level of dispersion and the intrinsic properties of LDH clay. Furthermore, cone calorimeter revealed intumescent behavior for LDH/EP nanocomposites and a higher reduction in the peak heat release rate compared to MMT/EP nanocomposites. 相似文献
10.
Giuseppe Ajroldi Maurizio Pianca Massimiliano Fumagalli Giovanni Moggi 《Polymer》1989,30(12):2180-2187
The dynamic-mechanical properties of some fluoroelastomers were determined as a function of composition at low frequency (≈ 1 Hz), by means of a free oscillation torsion pendulum, between −180°C and the softening point. Vinylidenefluoride (VDF)-hexafluoropropene (HFP) copolymers of molar composition 0–39% HFP and terpolymers of VDF and HFP with up to 30mol% tetrafluoroethylene (TFE) and a constant VDF to HFP molar ratio of 3.4 were considered. Two relaxation processes typical of the amorphous phase were found. The first, located at about −87°C, is related to local motions and the transition temperature was found to be independent of composition for copolymers, while it depends on TFE molar content for terpolymers. The second is related to the glass transition and the transition temperature depends on the composition. However, for semicrystalline copolymers the double glass transition phenomenon was observed. When crystallinity goes to zero at about 20 mol% HFP, only one transition is observed. It was also found that ordered structures can take place for terpolymers when TFE molar concentration exceeds 20%. The crystal disorder transition of pure PVDF (75°C) is observed also for low HFP concentrations but the transition temperature is strongly reduced. Analogies between the VDF-HFP and E-P systems are also discussed. 相似文献