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排序方式: 共有1105条查询结果,搜索用时 15 毫秒
961.
Claudia De Vitis Michela DAscanio Andrea Sacconi Dario Pizzirusso Valentina Salvati Massimiliano Mancini Giorgia Scafetta Roberto Cirombella Francesca Ascenzi Sara Bruschini Antonella Esposito Silvia Castelli Claudia Salvucci Leonardo Teodonio Bruno Sposato Angela Catizone Arianna Di Napoli Andrea Vecchione Gennaro Ciliberto Salvatore Sciacchitano Alberto Ricci Rita Mancini 《International journal of molecular sciences》2022,23(23)
Idiopathic pulmonary fibrosis (IPF) is a disease characterized by progressive scarring of the lung that involves the pulmonary interstitium. The disease may rapidly progress, leading to respiratory failure, and the long-term survival is poor. There are no accurate biomarkers available so far. Our aim was to evaluate the expression of the B4GALT1 in patients with IPF. Analysis of B4GALT1 gene expression was performed in silico on two gene sets, retrieved from the Gene Expression Omnibus database. Expression of B4GALT1 was then evaluated, both at the mRNA and protein levels, on lung specimens obtained from lung biopsies of 4 IPF patients, on one IPF-derived human primary cell and on 11 cases of IPF associated with cancer. In silico re-analysis demonstrated that the B4GALT1 gene was overexpressed in patients and human cell cultures with IPF (p = 0.03). Network analysis demonstrated that B4GALT1 upregulation was correlated with genes belonging to the EMT pathway (p = 0.01). The overexpression of B4GALT1 was observed, both at mRNA and protein levels, in lung biopsies of our four IPF patients and in the IPF-derived human primary cell, in other fibrotic non-lung tissues, and in IPF associated with cancer. In conclusion, our results indicate that B4GALT1 is overexpressed in IPF and could represent a novel marker of this disease. 相似文献
962.
Valentina Rep Kauli Livio Racan Marijana Leventi Domagoj ubari Vesna Rastija Ljubica Glava-Obrovac Silvana Rai-Mali 《International journal of molecular sciences》2022,23(24)
Syntheses of 6-halogen-substituted benzothiazoles were performed by condensation of 4-hydroxybenzaldehydes and 2-aminotiophenoles and subsequent O-alkylation with appropriate halides, whereas 6-amidino-substituted benzothiazoles were synthesized by condensation of 5-amidino-2-aminothiophenoles and corresponding benzaldehydes. While most of the compounds from non-substituted and halogen-substituted benzothiazole series showed marginal antiproliferative activity on tested tumor cell lines, amidino benzazoles exhibited stronger inhibitory activity. Generally, imidazolyl benzothiazoles showed pronounced and nonselective activity, with the exception of 36c which had a strong inhibitory effect on HuT78 cells (IC50 = 1.6 µM) without adverse cytotoxicity on normal BJ cells (IC50 >100 µM). Compared to benzothiazoles, benzimidazole structural analogs 45a–45c and 46c containing the 1,2,3-triazole ring exhibited pronounced and selective antiproliferative activity against HuT78 cells with IC50 < 10 µM. Moreover, compounds 45c and 46c containing the methoxy group at the phenoxy unit were not toxic to normal BJ cells. Of all the tested compounds, benzimidazole 45a with the unsubstituted phenoxy central core showed the most pronounced cell growth inhibition on THP1 cells in the nanomolar range (IC50 = 0.8 µM; SI = 70). QSAR models of antiproliferative activity for benzazoles on T-cell lymphoma (HuT78) and non-tumor MDCK-1 cells elucidated the effects of the substituents at position 6 of benzazoles, demonstrating their dependence on the topological and spatial distribution of atomic mass, polarizability, and van der Waals volumes. A notable cell cycle perturbation with higher accumulation of cells in the G2/M phase, and a significant cell increase in subG0/G1 phase were found in HuT78 cells treated with 36c, 42c, 45a–45c and 46c. Apoptotic morphological changes, an externalization of phosphatidylserine, and changes in the mitochondrial membrane potential of treated cells were observed as well. 相似文献
963.
This paper addresses two basic issues related to technological innovation and climate stabilization objectives: can innovation policies be effective in stabilizing climate? To what extent can innovation policies complement carbon pricing (taxes or permit trading) and improve the economic efficiency of a mitigation policy package? To answer these questions, we use an integrated assessment model with multiple externalities and an endogenous representation of the technical progress in the energy sector. We evaluate a range of innovation policies, both as stand-alone and in combination with other mitigation policies. Our analysis indicates that innovation policies alone are unlikely to stabilize global concentration and temperature. As for the benefits of combining climate and innovation policies, we find efficiency gains of 10% (6 USD Trillions in net present value terms) for a stringent climate policy, and 30% (3 USD Trillions) for a milder one. However, such gains are reduced when more plausible (sub-optimal) global innovation policy arrangements are considered. 相似文献
964.
Quentin SimonDavide Barreca Daniela BekermannAlberto Gasparotto Chiara MaccatoElisabetta Comini Valentina GombacPaolo Fornasiero Oleg I. LebedevStuart Turner Anjana DeviRoland A. Fischer Gustaaf Van Tendeloo 《International Journal of Hydrogen Energy》2011,36(24):15527-15537
Ag/ZnO nanocomposites were developed by a plasma-assisted approach. The adopted strategy exploits the advantages of Plasma Enhanced-Chemical Vapor Deposition (PE-CVD) for the growth of columnar ZnO arrays on Si(100) and Al2O3 substrates, in synergy with the infiltration power of the Radio Frequency (RF)-sputtering technique for the subsequent dispersion of different amounts of Ag nanoparticles (NPs). The resulting composites, both as-prepared and after annealing in air, were thoroughly characterized with particular attention on their morphological organization, structure and composition. For the first time, the above systems have been used as catalysts in the production of hydrogen by photo-reforming of alcoholic solutions, yielding a stable H2 evolution even by the sole use of simulated solar radiation. In addition, Ag/ZnO nanocomposites presented an excellent response in the gas-phase detection of H2, opening attractive perspectives for advanced technological applications. 相似文献
965.
Valentina Lazarescu Mihail F Lazarescu Wolfgang Schmickler 《Electrochimica acta》2004,49(24):4231-4238
Second harmonic generation from n-GaAs(1 0 0) electrodes in sulfuric acid solution has been investigated at an incident wavelength of 1064 nm over a potential range where Faradaic processes are excluded. In the p-in/p-out polarization configuration, the rotational anisotropy in the nonlinear response was found to depend both on the doping level and the applied potential. The effects of the applied potential on the isotropic amplitude of the SHG signal turned out to be closely related to the population of surface states as revealed by impedance spectroscopy, indicating that these states could play a significant role in second harmonic generation. 相似文献
966.
967.
Valentina G. Savinskaya Anatolii A. Adamovskii 《Powder Metallurgy and Metal Ceramics》2005,44(1-2):23-28
A procedure is developed for choosing a composite abrasive for grinding alloys that are hard to machine based on considering the interaction of tool materials and the article being machined. The efficiency of the procedure is demonstrated using the composite created for machining titanium alloys.__________Translated from Poroshkovaya Metallurgiya, Nos. 1–2(441), pp. 31–38, January–February, 2005. 相似文献
968.
This article summarizes several approaches for understanding the catalytic chemistry and “structure-surface acidity-reactivity” relationships in a multiplicity of catalytic applications of a continually increasing assemblage of metal-organic frameworks (MOFs) structures. The various spectroscopic techniques for acid-base characterization of MOFs are reviewed. The experimental requirements and the type and nature of probe molecules available are also discussed. Special emphasis is given to the revealing of the surface acid-base effect on the catalytic performance of MOFs. 相似文献
969.
Michela Murdocca Silvia Anna Ciafrè Paola Spitalieri Rosa Valentina Talarico Massimo Sanchez Giuseppe Novelli Federica Sangiuolo 《International journal of molecular sciences》2016,17(8)
Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by mutations in the Survival Motor Neuron 1 gene, resulting in very low levels of functional Survival of Motor Neuron (SMN) protein. SMA human induced Pluripotent Stem Cells (hiPSCs) represent a useful and valid model for the study of the disorder, as they provide in vitro the target cells. MicroRNAs (miRNAs) are often reported as playing a key role in regulating neuronal differentiation and fate specification. In this study SMA hiPSCs have been differentiated towards early motor neurons and their molecular and immunocytochemical profile were compared to those of wild type cells. Cell cycle proliferation was also evaluated by fluorescence-activated cell sorting (FACS). SMA hiPSCs showed an increased proliferation rate and also higher levels of stem cell markers. Moreover; when differentiated towards early motor neurons they expressed lower levels of NCAM and MN specific markers. The expression of miR-335-5p; already identified to control self-renewal or differentiation of mouse embryonic stem cells (mESCs); resulted to be reduced during the early steps of differentiation of SMA hiPSCs compared to wild type cells. These results suggest that we should speculate a role of this miRNA both in stemness characteristic and in differentiation efficiency of these cells. 相似文献
970.
Manuela Suess Christian Wilhelmi Milena Salvo Valentina Casalegno Peter Tatarko Matthias Funke 《International Journal of Applied Ceramic Technology》2017,14(3):313-322
The effect of a pulsed laser irradiation (Nd:YVO4, 1064 nm) in air on the surface morphology and chemical composition of silicon carbide and on the adhesion with an epoxy adhesive was investigated. Scanning and transmission electron microscopies, atomic force microscopy, and X‐ray photoelectron spectroscopy revealed that the laser treatment reduced the contamination level of the surface and induced the formation of a silica‐based nanostructured columnar layer on the SiC surface. The mechanism for the formation of five different microstructural regions is described in this paper. In addition, the formation of a 5‐10‐nm‐thick graphite layer between the oxide layer and SiC was observed. The joining test with Hysol® EA9321 showed that the nanostructured columnar silica layer was completely infiltrated by the adhesive, thus leading to a significant increase in the joined specific area and a mechanical interlocking at the adhesive/substrate interface. Nevertheless, the apparent shear strength of the joined SiC samples slightly decreased after the laser processing of the surfaces from about 42 MPa for lapped SiC to about 35 MPa for laser‐nanostructured SiC. The formation of the graphite layer was found to be responsible of the poor adhesion properties of the SiC surfaces modified by the laser radiation. 相似文献