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91.
Alessandra Bosutti Barbara Dapas Gabriele Grassi Rossana Bussani Fabrizio Zanconati Fabiola Giudici Cristina Bottin Nicola Pavan Carlo Trombetta Bruna Scaggiante 《International journal of molecular sciences》2022,23(8)
Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer. 相似文献
92.
Manuel Bethencourt Francisco Javier Botana María José Cano Leandro González-Rovira Mariano Marcos José María Sánchez-Amaya 《Metallurgical and Materials Transactions A》2012,43(1):182-194
A wide variety of anticorrosive treatments for aluminum alloys that can be employed as “green” alternatives to those based
on Cr(VI) are currently under development. This article reports a study of the morphological and anticorrosive characteristics
of surface layers formed on the Al–Cu alloy AA2017 by immersion treatment in baths of cerium salt, accelerated by increased
temperature and the employment of hydrogen peroxide. Scanning electron microscopy (SEM)/X-ray energy dispersive spectroscopy
(XEDS) studies of the samples treated have demonstrated the existence of a heterogeneous layer formed by a film of aluminum
oxide/hydroxide on the matrix, and a series of dispersed islands of cerium over the cathodic intermetallics. The protective
efficacy has been evaluated using electrochemical techniques, linear polarizations (LP) and electrochemical impedance spectroscopy
(EIS), and salt spray tests. The results obtained indicate that the layer provided good resistance to corrosion in media with
chlorides, and the method gives a considerable reduction of the time required for the immersion treatments. 相似文献
93.
Roberto Chiabrando Enrico Fabrizio Gabriele Garnero 《Renewable & Sustainable Energy Reviews》2009,13(9):2441-2451
The installation and operation of systems that exploit solar energy through photovoltaic conversion, recently promoted in some European countries by new sell-back tariffs, is a relevant transformation of the territory for various reasons (land use, elimination of the existing vegetation, visual impact on the components of the landscape, microclimate change, glare from the reflection of the direct sunlight). The weak energy intensity of the solar source coupled with the low conversion efficiency of the photovoltaic cells, make the physical dimensions of such systems relevant and, with them, also the environmental, territorial and landscape impacts that basically depend on the physical extent of the system. If it is well known that an incentive to the exploitation of renewable sources is one of the features of the policy of land conservation, including the one of the protected areas, at the same time the concerns of local communities and governments about the environmental, territorial and landscape impacts of this technology are increasing rapidly.Given this picture, this work is intended to clarify the territorial impacts of the ground mounted photovoltaic systems. Later, the paper concentrates on a specific impact, which is the assessment of the risk of glare by reflection of direct sunlight from the surfaces of photovoltaic modules. The methodologies that can be used to assess this impact and the outcomes of an evaluation carried out for a 5000 m2 PV system currently designed on a hilly territory in Italy are presented. 相似文献
94.
Roberto Grena Raffaele Scafè Fabrizio Pisacane Renzo Pilato Tommaso Crescenzi Domenico Mazzei 《Solar Energy》2010,84(1):51-58
Solar plants that use molten salts as heat transfer fluid need careful control to avoid the freezing of the salt in the pipes; if such a problem occurs, a diagnostic instrument to localize where is the frozen salt plug and to determine its length is useful. If the salt contains potassium (as is the case of the most common mixture used in solar plants, NaNO3/KNO3 60/40% by weight), the gamma decay of the natural unstable isotope 40K can be exploited to detect the frozen salt in a non-invasive way. Simulations and experimental results regarding the detectability of such plugs with different masses/lengths are presented. 相似文献
95.
96.
This paper deals with the performance of a Carbon Nano Tube Field Effect Transistor (CNTFET) in the presence of undeposited CNTs as defects. A simulation-based analysis of delay degradation due to different features (such as chirality and defective CNT distribution) is initially pursued. Two solutions to mitigate the change in delay are proposed; these approaches are based on adjusting the gate width of the CNTFET by lithography (and removing CNTs) as part of the fabrication process. These two methods reduce the average delay and its deviation, respectively. A probabilistic delay analysis is then presented. The performance of the proposed two adjustment methods is evaluated by considering CNT features (such as chirality and defect distribution) deterministically and probabilistically. By deterministic (probabilistic) simulation, the first method reduces on average the delay by 6.968 % (7.811 %) while the deviation is increased (decreased) by 32.444 % (9.788 %). The second method reduces deterministically (probabilistically) on average the deviation by 44.159 % (47.476 %) with 2.166 % (4.409 %) delay reduction. 相似文献
97.
G.N. Marichal Mariano ArtésJ.C. García Prada O. Casanova 《Mechanical Systems and Signal Processing》2011,25(6):2073-2082
In this paper, a classification system of faulty bearings based on a Neuro-Fuzzy approach is presented. The vibration signals in the frequency domain produced by the faulty bearings will be taken as the inputs to the classification system. In this sense, it is an essential characteristic for the used Neuro-Fuzzy approach, the possibility of taking a great number of inputs. The system consists of several Neuro-Fuzzy systems for determining different bearing status, along with a measurement equipment of the vibration spectral data. In this paper, a special attention is focused on the analysis of the rules obtained by the final Neuro-Fuzzy system. In fact, a rule extraction process and an interpretation rule process is discussed. Several trials have been carried out, taking into account the vibration spectral data collected by the measurement equipment, where satisfactory results have been achieved. 相似文献
98.
Dr. Irene Amata Mariano Maffei Dr. Ana Igea Dr. Marina Gay Dr. Marta Vilaseca Dr. Angel R. Nebreda Prof. Dr. Miquel Pons 《Chembiochem : a European journal of chemical biology》2013,14(14):1820-1827
Intrinsically disordered regions (IDRs) are preferred sites for post‐translational modifications essential for regulating protein function. The enhanced local mobility of IDRs facilitates their observation by NMR spectroscopy in vivo. Phosphorylation events can occur at multiple sites and respond dynamically to changes in kinase–phosphatase networks. Here we used real‐time NMR spectroscopy to study the effect of kinases and phosphatases present in Xenopus oocytes and egg extracts on the phosphorylation state of the “unique domain” of c‐Src. We followed the phosphorylation of S17 in oocytes, and of S17, S69, and S75 in egg extracts by NMR spectroscopy, MS, and western blotting. Addition of specific kinase inhibitors showed that S75 and S69 are phosphorylated by CDKs (cyclin‐dependent kinases) differently from Cdk1. Moreover, although PKA (cAMP‐dependent protein kinase) can phosphorylate S17 in vitro, this was not the major S17 kinase in egg extracts. Changes in PKA activity affected the phosphorylation levels of CDK‐dependent sites, thus suggesting indirect effects of kinase–phosphatase networks. This study provides a proof‐of‐concept of the use of real‐time in vivo NMR spectroscopy to characterize kinase/phosphatase effects on intrinsically disordered regulatory domains. 相似文献
99.
100.
Gianluca Paravati Andrea Sanna Fabrizio Lamberti Luigi Ciminiera 《Mobile Networks and Applications》2011,16(3):385-393
Wireless communication advances have enabled emerging video streaming applications to mobile handheld devices. For example,
it is possible to display and interact with complex 3D virtual environments on mobile devices that don’t have enough computational
and storage capabilities (e.g. smart phones, PDAs) through remote rendering techniques, where a server renders 3D data and
streams the corresponding image flow to the client. However, due to fluctuations in bandwidth characteristics and limited
mobile device CPU capabilities, it is extremely challenging to design effective systems for streaming interactive multimedia
over wireless networks. This paper presents a novel approach based on a controller that can automatically adjust streaming
parameters basing on feedback measures from the client device. Experimental results prove the effectiveness of the proposed
solution in coping with bandwidth changes, thus providing high Quality of Service (QoS) in remote visualizations. 相似文献