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191.
Ignazio G. Vetrano Michele Dei Cas Vittoria Nazzi Marica Eoli Niccol Innocenti Veronica Saletti Antonella Potenza Tatiana Carrozzini Giuliana Pollaci Gemma Gorla Rita Paroni Riccardo Ghidoni Laura Gatti 《International journal of molecular sciences》2022,23(1)
Peripheral nerve sheath tumors (PNSTs) include schwannomas, neurofibromas (NFs), and plexiform neurofibromas (PNFs), among others. While they are benign tumors, according to their biological behavior, some have the potential for malignant degeneration, mainly PNFs. The specific factors contributing to the more aggressive behavior of some PNSTs compared to others are not precisely known. Considering that lipid homeostasis plays a crucial role in fibrotic/inflammatory processes and in several cancers, we hypothesized that the lipid asset was also unbalanced in this group of nerve tumors. Through untargeted lipidomics, NFs presented a significant increase in ceramide, phosphatidylcholine, and Vitamin A ester. PNFs displayed a marked decrease in 34 out of 50 lipid class analyzed. An increased level of ether- and oxidized-triacylglycerols was observed; phosphatidylcholines were reduced. After sphingolipidomic analysis, we observed six sphingolipid classes. Ceramide and dihydroceramides were statistically increased in NFs. All the glycosylated species appeared reduced in NFs, but increased in PNFs. Our findings suggested that different subtypes of PNSTs presented a specific modulation in the lipidic profile. The untargeted and targeted lipidomic approaches, which were not applied until now, contribute to better clarifying bioactive lipid roles in PNS natural history to highlight disease molecular features and pathogenesis. 相似文献
192.
Gustavo A. Abraham Alberto Gallardo Antonella Motta Claudio Migliaresi Julio San Romn 《大分子材料与工程》2000,282(1):44-50
Poly(methyl methacrylate) – polycaprolactone (PMMA/PCL) microheterogeneous beads were synthesized by suspension polymerization starting from methyl methacrylate (MMA) monomer and PCL, which was synthesized by ring‐opening polymerization of ε‐caprolactone using ZnCl2 as initiator. The resulting polymer was fully characterized by 1H and 13C NMR, differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and dynamic mechanical thermal analysis (DMTA). The size distribution and morphology of the resulting beads were investigated by optical microscopy and scanning electron microscopy (SEM). Moreover, blends of PMMA beads and PCL in different proportions were prepared and the morphology of the films was examined by optical microscopy. The low compatibility between PMMA and PCL was clearly evidenced through these experiments. 相似文献
193.
Nicoletta De Francesco Antonella Santone 《Software Testing, Verification and Reliability》2002,12(3):173-186
A well‐known problem in the verification of concurrent systems based on model checking is state explosion: concurrent systems are often represented by automata with a prohibitive number of states. A reduction technique to reduce state explosion in deadlock checking is presented. The method is based on an automatic syntactic simplification of a calculus of communicating systems (CCS) specification, which keeps the parts of the program structure that may lead to a deadlock and deletes the other parts. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
194.
Mariah P. Csolle Lisa M. Ooms Antonella Papa Christina A. Mitchell 《International journal of molecular sciences》2020,21(23)
The phosphoinositide 3-kinase (PI3K)/AKT signalling pathway is hyperactivated in ~70% of breast cancers. Class I PI3K generates PtdIns(3,4,5)P3 at the plasma membrane in response to growth factor stimulation, leading to AKT activation to drive cell proliferation, survival and migration. PTEN negatively regulates PI3K/AKT signalling by dephosphorylating PtdIns(3,4,5)P3 to form PtdIns(4,5)P2. PtdIns(3,4,5)P3 can also be hydrolysed by the inositol polyphosphate 5-phosphatases (5-phosphatases) to produce PtdIns(3,4)P2. Interestingly, while PTEN is a bona fide tumour suppressor and is frequently mutated/lost in breast cancer, 5-phosphatases such as PIPP, SHIP2 and SYNJ2, have demonstrated more diverse roles in regulating mammary tumourigenesis. Reduced PIPP expression is associated with triple negative breast cancers and reduced relapse-free and overall survival. Although PIPP depletion enhances AKT phosphorylation and supports tumour growth, this also inhibits cell migration and metastasis in vivo, in a breast cancer oncogene-driven murine model. Paradoxically, SHIP2 and SYNJ2 are increased in primary breast tumours, which correlates with invasive disease and reduced survival. SHIP2 or SYNJ2 overexpression promotes breast tumourigenesis via AKT-dependent and independent mechanisms. This review will discuss how PTEN, PIPP, SHIP2 and SYNJ2 distinctly regulate multiple functional targets, and the mechanisms by which dysregulation of these distinct phosphoinositide phosphatases differentially affect breast cancer progression. 相似文献
195.
Dielectric,mechanical and transport properties of bisphenol A polycarbonate/graphene nanocomposites prepared by melt blending
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Andrea Oyarzabal Antonella Cristiano‐Tassi Estrella Laredo Dinorah Newman Alfredo Bello Agustín Etxeberría José Ignacio Eguiazabal Manuela Zubitur Agurtzane Mugica Alejandro J. Müller 《应用聚合物科学杂志》2017,134(13)
Nanocomposites based on polycarbonate (PC) and different amounts of untreated graphene nanoplatelets (GnP) (from 1 to 7 wt %) were prepared by melt blending. The nanocomposites were thoroughly characterized employing the following techniques: broad band dielectric spectroscopy, thermally stimulated depolarization currents, differential scanning calorimetry, tensile testing, dynamic mechanical thermal analysis, and water vapor, carbon dioxide and oxygen permeability measurements. The presence of a MWS relaxation mode indicated the accumulation of electrical charges trapped at the interfaces of the polycarbonate with graphene 2D platelets. The addition of GnP produced nanocomposite materials with enhanced mechanical and barrier properties. The melt mixed PC/graphene nanocomposites prepared here exhibit well‐balanced properties, even though unmodified graphene nanoplatelets were used. In addition, the nanocomposites were obtained by a single extrusion process, which is easily scalable for industrial applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44654. 相似文献
196.
The nutraceutical quality of tomato fruit during domestic storage is affected by chitosan coating
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Carlos Henrique Pagno Antonella Castagna Alice Trivellini Anna Mensuali‐Sodi Annamaria Ranieri Ester Alice Ferreira Alessandro de Oliveira Rios Simone Hickmann Flôres 《Journal of Food Processing and Preservation》2018,42(1)
Fruits and vegetables are highly perishable foods which usually undergo a gradual loss of nutraceuticals during storage. Chitosan‐based edible coatings are extensively studied thanks to antimicrobial activity and great potential to extend the shelf life. However, little information is presently available on the nutraceutical quality of chitosan‐coated products. The present study is addressed to evaluate accompanied by a delayed degradation of some phenolic compounds during storage. These results indicate that chitosan coating is effective in maintaining the quality parameters, the coated fruit showed less weight loss (?16%) and more firmer (+40%) than control fruit, chitosan‐coated tomato emitted significantly lower ethylene (?41%) than control, and slowing down the nutraceutical loss occurring in postharvest, mainly of the lycopene, main carotenoid, found in tomato fruits. These results indicate that chitosan coating is effective in slowing down the nutraceutical loss occurring in postharvest, thus representing a promising tool to preserve bio‐protective phytochemicals during fruit conservation.
Practical applications
During storage and domestic conservation, the nutraceutical quality of fruits and vegetables usually decreases and can undergo deterioration due to physiological disorders and mechanical damages. In the last decade, use of edible coatings has attracted interest as a promising technology to prolong the shelf life of particularly perishable foods. These coatings act as protective barriers decreasing transpiration rate and gas transfer across the product surface, thus promoting the maintenance of nutritional quality. 相似文献197.
Expanding the Potential of G‐Quadruplex Structures: Formation of a Heterochiral TBA Analogue
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Dr. Antonella Virgilio Prof. Michela Varra Dr. Maria Scuotto Dr. Antonella Capuozzo Dr. Carlo Irace Prof. Luciano Mayol Dr. Veronica Esposito Prof. Aldo Galeone 《Chembiochem : a European journal of chemical biology》2014,15(5):652-655
In order to expand the potential applications of G‐quadruplex structures, we explored the ability of heterochiral oligodeoxynucleotides based on the thrombin‐binding aptamer (TBA) sequence to fold into similar complexes, with particular focus on their resistance in biological environments. A combination of CD and NMR techniques was used. Similarly to TBA, the ODN ggTTggtgtggTTgg (lower case letters indicate L residues) is able to fold into a chair‐like antiparallel G‐quadruplex structure, but has a slightly higher thermal stability. The discovery that heterochiral ODNs are able to form stable G‐quadruplex structures opens up new possibilities for their development in several fields, as aptamers, sensors and, as recently shown, as catalysts for enantioselective reactions. 相似文献
198.
Rita Pepponi Roberta De Simone Chiara De Nuccio Sergio Visentin Andrea Matteucci Antonietta Bernardo Patrizia Popoli Antonella Ferrante 《International journal of molecular sciences》2022,23(7)
Niemann Pick type C disease (NPC) is a rare disorder characterized by lysosomal lipid accumulation that damages peripheral organs and the central nervous system. Currently, only miglustat is authorized for NPC treatment in Europe, and thus the identification of new therapies is necessary. The hypothesis addressed in this study is that increasing adenosine levels may represent a new therapeutic approach for NPC. In fact, a reduced level of adenosine has been shown in the brain of animal models of NPC; moreover, the compound T1-11, which is able to weakly stimulate A2A receptor and to increase adenosine levels by blocking the equilibrative nucleoside transporter ENT1, significantly ameliorated the pathological phenotype and extended the survival in a mouse model of the disease. To test our hypothesis, fibroblasts from NPC1 patients were treated with dipyridamole, a clinically-approved drug with inhibitory activity towards ENT1. Dipyridamole significantly reduced cholesterol accumulation in fibroblasts and rescued mitochondrial deficits; the mechanism elicited by dipyridamole relies on activation of the adenosine A2AR subtype subsequent to the increased levels of extracellular adenosine due to the inhibition of ENT1. In conclusion, our results provide the proof of concept that targeting adenosine tone could be beneficial in NPC. 相似文献
199.
Katia Pane Cristina Quintavalle Silvia Nuzzo Francesco Ingenito Giuseppina Roscigno Alessandra Affinito Iolanda Scognamiglio Birlipta Pattanayak Enrico Gallo Antonella Accardo Guglielmo Thomas Zoran Minic Maxim V. Berezovski Monica Franzese Gerolama Condorelli 《International journal of molecular sciences》2022,23(7)
Extracellular vesicles (EVs) shuttle proteins, RNA, DNA, and lipids crucial for cell-to-cell communication. Recent findings have highlighted that EVs, by virtue of their cargo, may also contribute to breast cancer (BC) growth and metastatic dissemination. Indeed, EVs are gaining great interest as non-invasive cancer biomarkers. However, little is known about the biological and physical properties of EVs from malignant BC lesions, and even less is understood about EVs from non-malignant lesions, such as breast fibroadenoma (FAD), which are clinically managed using conservative approaches. Thus, for this pilot study, we attempted to purify and explore the proteomic profiles of EVs from benign breast lesions, HER2+ BCs, triple–negative BCs (TNBCs), and continuous BC cell lines (i.e., BT-549, MCF–10A, and MDA-MB-231), combining experimental and semi-quantitative approaches. Of note, proteome-wide analyses showed 49 common proteins across EVs harvested from FAD, HER2+ BCs, TNBCs, and model BC lines. This is the first feasibility study evaluating the physicochemical composition and proteome of EVs from benign breast cells and primary and immortalized BC cells. Our preliminary results hold promise for possible implications in precision medicine for BC. 相似文献
200.
Andrea Speltini Andrea Scalabrini Federica Maraschi Michela Sturini Ambra Pisanu Lorenzo Malavasi Antonella Profumo 《International Journal of Hydrogen Energy》2018,43(32):14925-14933
Chemically modified g-C3N4 for the photocatalytic H2 evolution from water was explored. Bulk g-C3N4 was treated in hot HNO3 aqueous solution to obtain the oxidized material (o-g-C3N4), tested in water containing glucose as model water-soluble sacrificial biomass, using Pt as co-catalyst, under simulated solar light. The behaviour of o-g-C3N4 was studied in relation with catalyst amount, Pt loading, glucose concentration. Results showed that H2 production is favoured by increasing glucose concentration up to 0.1 M and Pt loading up to 3 wt%, and it resulted strongly enhanced using small amount of o-g-C3N4 (0.25 g L?1). o-g-C3N4 possesses superior photocatalytic activity (~26-fold higher) compared to pristine g-C3N4, with H2 evolution further improved by ultrasound-assisted exfoliation and evolution rates up to ca. 1370 μmol h?1 per gram of catalyst, with excellent reproducibility (RSD < 6%, n = 3). Significant production was observed also in river water and seawater, with results far better (up to ca. 2500 μmol g?1 h?1) compared to commercial AEROXIDE® P25 TiO2 under natural solar light. 相似文献