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121.
Righi V Di Nunzio M Danesi F Schenetti L Mucci A Boschetti E Biagi P Bonora S Tugnoli V Bordoni A 《Lipids》2011,46(7):627-636
It is well recognized that a high dietary intake of long-chain polyunsaturated fatty acids (LC-PUFA) has profound benefits
on health and prevention of chronic diseases. In particular, in recent years there has been a dramatic surge of interest in
the health effects of n-3 LC-PUFA derived from fish, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Notwithstanding,
the metabolic fate and the effects of these fatty acids once inside the cell has seldom been comprehensively investigated.
Using cultured neonatal rat cardiomyocytes as model system we have investigated for the first time, by means of high-resolution
magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy in combination with gas chromatography (GC), the
modification occurring in the cell lipid environment after EPA and DHA supplementation. The most important difference between
control and n-3 LC-PUFA-supplemented cardiomyocytes highlighted by HR-MAS NMR spectroscopy is the increase of signals from
mobile lipids, identified as triacylglycerols (TAG). The observed increase of mobile TAG is a metabolic response to n-3 LC-PUFA
supplementation, which leads to an increased lipid storage. The sequestration of mobile lipids in lipid bodies provides a
deposit of stored energy that can be accessed in a regulated fashion according to metabolic need. Interestingly, while n-3
LC-PUFA supplementation to neonatal rat cardiomyocytes causes a huge variation in the cell lipid environment, it does not
induce detectable modifications in water-soluble metabolites, suggesting negligible interference with normal metabolic processes. 相似文献
122.
Milan Erdelj Valeria Loscrí Enrico Natalizio Tahiry Razafindralambo 《Ad hoc Networks》2013,11(8):2288-2300
Environmental monitoring has become a typical application of wireless sensor networks. The concept of monitoring certain Points of Interest (PoIs) instead of the whole sensor field helps in reducing the costs of the deployment and improving the performance in terms of coverage. However, the problems of multiple PoI discovery, coverage and data report are still solved separately and there are no works that combine the aforementioned problems into a single deployment scheme. In this work, we present a novel approach for mobile sensor deployment, where we combine multiple PoI discovery and coverage with network connectivity preservation in order to capture the dynamics of the monitored area. Furthermore, we derive analytical expressions for circular movement parameters and examine the performance of our approach through extensive simulation campaigns. 相似文献
123.
Amanda Cia Hetzl Fabio Montico Raisa Misitieri Larissa Kido Eduardo Cândido Athanase Billis Ubirajara Ferreira Valeria Ha Cagnon 《Microscopy research and technique》2013,76(3):321-330
The objective was to characterize and associate the receptor reactivities of fibroblastic growth factor (FGF)‐2, FGF‐7, FGF‐8, epidermal growth factor (EGF), α‐actin and vimentin in relation to the androgen receptor (AR), α and β estrogen receptors (ERα and ERβ), and prolactin receptor in the prostate of elderly men showing low‐ and high‐grade adenocarcinoma. Thirty prostatic samples were taken from 60‐ to 90‐year‐old patients without prostatic lesions and with low‐grade cancer and high‐grade cancer, from the University Hospital, School of Medicine, the State University of Campinas. The results showed that increased FGF‐2, FGF‐7, and FGF‐8 receptor reactivities and decreased AR reactivity were verified in both high‐ and low‐grade cancer. However, the FGF‐8 receptor showed greater involvement at the beginning of the malignancy alterations. Increased EGF receptor (EGFR) reactivity and diminished α‐actin immunohistochemistry were identified in both cancer groups. Also, increased ERα, PR, and vimentin receptors were verified in both cancer groups. To conclude, the ERα involvement in the reactive stroma activation led to a microenvironment, which was favorable to cancer progression, due to maximizing stromal imbalance. The prolactin could be related to cancer progression due to its interaction with ERα action, indicating that this hormone could be a relevant target to prevent the estrogenic effects in the prostatic lesions. Both FGF receptor (FGFR)‐2 and FGFR‐8 play a fundamental role in the early stages of prostate cancer, suggesting that these molecules could be a promising therapeutic target. The differential localization of the fibroblastic factors between the prostatic epithelium and stroma of elderly men, who presented prostate cancer, could indicate a favorable distinction for tumoral progression. Microsc. Res. Tech. 76:321–330, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
124.
Paola Fabbri Valeria Cannillo Antonella Sola Andrea Dorigato Federica Chiellini 《Composites Science and Technology》2010
Highly porous biocompatible composites made of polycaprolactone (PCL) and 45S5 Bioglass® (BG) were prepared by a solid–liquid phase separation method (SLPS). The composites were obtained with BG weight contents varying in the range 0–50%, using either dimethylcarbonate (DMC) or dioxane (DIOX) as solvent, and ethanol as extracting medium. The porosity of the scaffolds was estimated to be about 88–92%. Mechanical properties showed a dependence on the amount of BG in the composites, but also on the kind of solvent used for preparation, composites prepared with DIOX showing enhanced stress at deformation with respect to composites prepared with DMC (stress at 60% of deformation being as high as 214 ± 17 kPa for DIOX-prepared composites and 98 ± 24 kPa for DMC-prepared ones, with 50 wt/wtPCL% of glass), as well as higher elastic modulus (whose value was 251 ± 32 kPa for DIOX-prepared scaffolds and 156 ± 36 kPa for DMC-prepared ones, always with 50 wt/wtPCL% of glass). The ability of the composites to induce precipitation of hydroxyapatite was positively evaluated by means of immersion in simulated body fluid and the best results were achieved with high glass amounts (50 wt/wtPCL%). In vitro tests of cytotoxicity and osteoblast proliferation showed that, even if the scaffolds are to be considered non-cytotoxic, cells suffer from the scarce wettability of the composites. 相似文献
125.
Ciarrocca M Tomei F Bernardini A Capozzella A Fiore P Amicarelli V Sancini A Perugi F Firullo E Rosati MV Pimpinella B Monti C Tomei G 《The Science of the total environment》2006,370(1):17-22
Urban outside workers, such as traffic police, are daily exposed to air pollutants and psychosocial stressors: for these workers, the working environment corresponds to the living environment of the general population. Studies in the literature have shown that immune parameters could be affected by chronic exposure to various chemical pollutants. The aim of this study is to evaluate whether occupational exposure to urban pollutants can cause alterations in NK, IL-2, IFN-gamma and C3 plasma levels in female traffic police compared to a control group. After excluding subjects with the principal confounding factors, 86 female traffic police and 87 controls were matched by age, years of police work and habitual alcohol consumption. The distribution of NK values in female traffic police and controls was significantly different (p=0.000); NK values above the upper limit of the normal laboratory range were observed in 23 female traffic police and in 2 controls (p=0.000). IL-2 mean levels were higher in traffic police compared to controls, but the difference was not significant. The mean and the distribution of IFN-gamma values in female traffic police and controls were not different. C3 mean levels were higher in female traffic police versus controls, but the difference was not significant. Considering that the subjects with the principal confounding factors were excluded from the study and that female traffic police and controls were matched by the above-mentioned variables, our results suggest that chronic occupational exposure to low doses of chemical stressors, which may interact with and add to psychosocial ones, can affect both innate and adaptative immunity. 相似文献
126.
Tamara Montes Valeria Grazú Isabel Manso Beatriz Galn Fernando Lpez‐Gallego Ramn Gonzlez JuanA. Hermoso JosL. García JosM. Guisn Roberto Fernndez‐Lafuente 《Advanced Synthesis \u0026amp; Catalysis》2007,349(3):459-464
Penicillin G acylase (PGA) is an enzyme that hardly interacts with polycationic polymers (e.g., polyethyleneimine, PEI) and thus the enzyme cannot be stabilized against the action of organic solvents by its co‐immobilization with the polymer in the same support, neither covalently attached to the support nor adsorbed on the already immobilized enzyme. However, a new mutant PGA bearing eight additional Glu residues homogenously distributed throughout the enzyme surface may interact with the polymer. The co‐immobilization of the enzyme and PEI on glyoxyl‐agarose allows one to fully take advantage of the stabilization produced by the multipoint covalent attachment and by the protective hydrophilic micro‐environment generated by the polycationic polymer, enabling a significant stabilization of the immobilized PGA in the presence of organic solvents. 相似文献
127.
Freddy Romm Valeria Karchevsky Oleg Figovsky 《Journal of surfactants and detergents》2000,3(4):475-481
Quaternary ammonium silicate is a surfactant with very high content of silica that allows its use for preparation of protective
coatings. The problem of silica aggregation from quaternary ammonium solution in limited volume is the focus of this paper.
The system is described by a model based on a Monte Carbo approach with thermodynamic limitations. Thermodynamic characteristics
are estimated by statistical polymer method. The model is employed for estimation of such properties as monomer concentration
and tortuosity. The results of computer simulation are used for forecasting properties of coatings and for practical preparation
of samples coated with quaternary ammonium silicate-based composition. 相似文献
128.
Morena Petrini Tania Vanessa Pierfelice Emira DAmico Natalia Di Pietro Assunta Pandolfi Camillo DArcangelo Francesco De Angelis Domitilla Mandatori Valeria Schiavone Adriano Piattelli Giovanna Iezzi 《International journal of molecular sciences》2021,22(18)
Current research on dental implants has mainly focused on the influence of surface roughness on the rate of osseointegration, while studies on the development of surfaces to also improve the interaction of peri-implant soft tissues are lacking. To this end, the first purpose of this study was to evaluate the response of human gingival fibroblasts (hGDFs) to titanium implant discs (Implacil De Bortoli, Brazil) having different micro and nano-topography: machined (Ti-M) versus sandblasted/double-etched (Ti-S). The secondary aim was to investigate the effect of the macrogeometry of the discs on cells: linear-like (Ti-L) versus wave-like (Ti-W) surfaces. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis showed that the Ti-S surfaces were characterized by a significantly higher micro and nano roughness and showed the 3D macrotopography of Ti-L and Ti-W surfaces. For in vitro analyses, the hGDFs were seeded into titanium discs and analyzed at 1, 3, and 5 days for adhesion and morphology (SEM) viability and proliferation (Cck-8 and MTT assays). The results showed that all tested surfaces were not cytotoxic for the hGDFs, rather the nano-micro and macro topography favored their proliferation in a time-dependent manner. Especially, at 3 and 5 days, the number of cells on Ti-L was higher than on other surfaces, including Ti-W surfaces. In conclusion, although further studies are needed, our in vitro data proved that the use of implant discs with Ti-S surfaces promotes the adhesion and proliferation of gingival fibroblasts, suggesting their use for in vivo applications. 相似文献
129.
Johanna Lieb Valeria Demontis Domenic Prete Daniele Ercolani Valentina Zannier Lucia Sorba Shimpei Ono Fabio Beltram Benjamin Sacp Francesco Rossella 《Advanced functional materials》2019,29(3)
Here, the operation of a field‐effect transistor based on a single InAs nanowire gated by an ionic liquid is reported. Liquid gating yields very efficient carrier modulation with a transconductance value 30 times larger than standard back gating with the SiO2/Si++ substrate. Thanks to this wide modulation, the controlled evolution from semiconductor to metallic‐like behavior in the nanowire is shown. This work provides the first systematic study of ionic‐liquid gating in electronic devices based on individual III–V semiconductor nanowires: this architecture opens the way to a wide range of fundamental and applied studies from the phase transitions to bioelectronics. 相似文献
130.