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91.
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
92.
Lalitha Kodumudi Venkataraman Tingting Zhu Monica Pinto Salazar Kathrin Hofmann Aamir Iqbal Waidha J. C. Jaud Pedro B. Groszewicz Jürgen Rödel 《Journal of the American Ceramic Society》2021,104(5):2201-2212
Na1/2Bi1/2TiO3-based materials have been earmarked for one of the first large-volume applications of lead-free piezoceramics in high-power ultrasonics. Zn2+-doping is demonstrated as a viable route to enhance the thermal depolarization temperature and electromechanically harden (1-y)Na1/2Bi1/2TiO3-yBaTiO3 (NBT100yBT) with a maximum achievable operating temperature of 150 °C and mechanical quality factor of 627 for 1 mole % Zn2+-doped NBT6BT. Although quenching from sintering temperatures has been recently touted to enhance TF-R, with quenching the doped compositions featuring an additional increase in TF-R by 17 °C, it exhibits negligible effect on the electromechanical properties. The effect is rationalized considering the missing influence on conductivity and therefore, negligible changes in the defect chemistry upon quenching. High-resolution diffraction indicates that Zn2+-doped samples favor the tetragonal phase with enhanced lattice distortion, further corroborated by 23Na Nuclear Magnetic Resonance investigations. 相似文献
93.
The inversion of the normal reactivity (umpolung) of aldehydes has been induced via N-heterocyclic carbenes (NHCs) thiazol-2-ylidenes 2a or 3a, generated by simple electrolyses of solutions containing thiazolium salt 2 or 3. Accordingly, 1,4-dicarbonyl compounds have been obtained, in mild conditions and in moderate to very high yields, via 1,4-addition of the Breslow intermediates to the suitable Michael acceptor. The procedure has been performed in classical organic solvents (VOCs) as well as in room temperature ionic liquids (RTILs). The different reactivity of aliphatic aldehydes vs the one of aromatic and heteroaromatic aldehydes has been emphasized. 相似文献
94.
Sueva Cantalupo Vito Alessandro Lasorsa Roberta Russo Immacolata Andolfo Giuseppe DAlterio Barbara Eleni Rosato Giulia Frisso Pasquale Abete Gian Marco Cassese Giuseppe Servillo Ivan Gentile Carmelo Piscopo Matteo Della Monica Giuseppe Fiorentino Giuseppe Russo Pellegrino Cerino Carlo Buonerba Biancamaria Pierri Massimo Zollo Achille Iolascon Mario Capasso 《International journal of molecular sciences》2021,22(10)
Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10−5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5. 相似文献
95.
Anna Campanati Emanuela Martina Federico Diotallevi Giulia Radi Andrea Marani Davide Sartini Monica Emanuelli George Kontochristopoulos Dimitris Rigopoulos Stamatis Gregoriou Annamaria Offidani 《International journal of molecular sciences》2021,22(13)
Saliva is easy to access, non-invasive and a useful source of information useful for the diagnosis of serval inflammatory and immune-mediated diseases. Following the advent of genomic technologies and -omic research, studies based on saliva testing have rapidly increased and human salivary proteome has been partially characterized. As a proteomic protocol to analyze the whole saliva proteome is not currently available, the most common aim of the proteomic analysis is to discriminate between physiological and pathological conditions. The salivary proteome has been initially investigated in several diseases: oral squamous cell carcinoma and oral leukoplakia, chronic graft-versus-host disease, and Sjögren’s syndrome. Otherwise, salivary proteomics studies in the dermatological field are still in the initial phase, thus the aim of this review is to collect the best research evidence on the role of saliva proteomics analysis in immune-mediated skin diseases to understand the direction of research in this field. The results of PRISMA analysis reported herein suggest that human saliva analysis could provide significant data for the diagnosis and prognosis of several immune-mediated and inflammatory skin diseases in the next future. 相似文献
96.
Alice Perrin Monica Sorescu Mari-Therese Burton David E. Laughlin Michael McHenry 《JOM Journal of the Minerals, Metals and Materials Society》2017,69(11):2125-2129
This paper explores the FeCoNiCuMn high-entropy alloy system, where small departures from equiatomic composition have yielded technologically interesting 300-K Curie temperatures (\(T_{\mathrm{c}}\)), making them promising for magnetocaloric applications. We also demonstrate that the small deviations from equiatomic compositions do not affect the structural stability of our single-phase fcc-based solid solutions. Room-temperature Mössbauer spectroscopy measurements provide evidence for the distributed exchange interactions (\(J_{\mathrm{ex}}\)) occurring between the magnetic elements, which contribute to a broadened magnetocaloric effect observed for these alloys. The average hyperfine field observed in the Mössbauer spectra decreases as the \(T_{\mathrm{c}}\) of the alloys decrease, confirming direct current magnetic measurements. Multiple peaks in the hyperfine field distribution are interpreted considering pairwise ferromagnetic or antiferromagnetic \(J_{\mathrm{ex}}\) between all elements except the Cu diluent as contributing to overall magnetic exchange in the alloy. 相似文献
97.
Chemical Defense of the Caribbean Reef Sponge Axinella corrugata Against Predatory Fishes 总被引:2,自引:0,他引:2
Dean M. Wilson Monica Puyana William Fenical Joseph R. Pawlik 《Journal of chemical ecology》1999,25(12):2811-2823
Field and laboratory experiments were performed to investigate the palatability to predatory fishes of organic extracts and purified compounds from the Caribbean reef sponge Axinella corrugata (=Teichaxinella morchella). When incorporated into artificial foods at the same volumetric concentration as found in sponge tissue, crude extracts of the sponge, as well as a butanol-soluble partition of the crude extract, deterred feeding of the Caribbean reef fish Thalassoma bifasciatum in laboratory aquarium assays and deterred feeding of a natural assemblage of fishes in assays performed on reefs where A. corrugata is found. Bioassay-directed fractionation of the butanol-soluble partition led to the isolation of a single compound responsible for feeding deterrency, stevensine, a previously described dibrominated alkaloid. The mean concentration of stevensine in A. corrugata, as determined by quantitative NMR analysis, was 19.0 mg/ml (N = 8, SD = 7.2 mg/ml). Stevensine deterred feeding in laboratory aquarium assays at concentrations >2.25 mg/ml, and deterred feeding in field assays at ~12 mg/ml. Stevensine represents another in the oroidin class of brominated pyrrole derivatives that function as chemical defenses of sponges in the families Axinellidae and Agelasidae. 相似文献
98.
Advances in Bioapplications of Carbon Nanotubes 总被引:1,自引:0,他引:1
Fushen Lu Lingrong Gu Mohammed J. Meziani Xin Wang Pengju G. Luo Lucia Monica Veca Li Cao Ya‐Ping Sun 《Advanced materials (Deerfield Beach, Fla.)》2009,21(2):139-152
This progress report provides an overview on recent advances in bioapplications of carbon nanotubes including the chemical modification of carbon nanotubes, targeting specifically their covalent and noncovalent conjugations with a variety of biological and bioactive species (proteins and peptides, DNAs/RNAs, and carbohydrates). Furthermore, the significant recent development and progress in the use of carbon nanotubes for biosensors, drug and other delivery systems, bioimaging, etc. and in the understanding of in vivo biodistribution and toxicity of carbon nanotubes are reported. 相似文献
99.
Antonio Fiorentino Claudio Mastellone Brigida D’Abrosca Severina Pacifico Monica Scognamiglio Giuseppe Cefarelli Romualdo Caputo Pietro Monaco 《Food chemistry》2009
A new vitamin E, δ-tocomonoenol, has been isolated from Actinidia chinensis (kiwi) fruits. The new structure, 2,8-dimethyl-2-(4,8,12-trimethyltridec-11-enyl)chroman-6-ol, has been elucidated on the basis of EIMS, 1D, and 2D NMR spectral data. GC–MS analysis of peels and pulps of kiwi showed that the new compound, together with δ-tocopherol, is mainly present in the fruit peel, whilst α-tocopherol is present in a similar amount in both matrices. The compound was tested for its radical-scavenging and antioxidant capabilities, by measuring its ability to scavenge DPPH (2,2′-diphenyl-1-picrylhydrazyl radical) and anion superoxide radical, and inhibit the formation of methyl linoleate conjugated diene hydroperoxides and TBARS (thiobarbituric acid reactive species). 相似文献
100.
In this article the authors use the imaginal worlds of three children’s stories to explore variations in the affective quality of potential space. Lewis Carroll’s Alice in Wonderland, C. S. Lewis’ The Lion, the Witch, and the Wardrobe, and Norton Juster’s The Phantom Toolbooth, each contain a metaphor of transition in which the protagonist moves from the real space of the narrative into the imaginary space where the action takes place—the protagonists are altered and alter their own worlds. The authors will use these metaphors as analogues to differing qualities of imaginary space, including the collapse of meaning in schizoid states, the play of meaning in mentalization and the adventurousness of negotiating separation. These metaphors of transitioning into imaginary space may be used to think about disruptions in development as they manifest in clinical process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献