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91.
92.

Background  

Superoxide mediated oxidative stress is a key neuropathologic mechanism in acute central nervous system injuries. We have analyzed the neuroprotective efficacy of the transient overexpression of antioxidant enzyme Cu/Zn Superoxide dismutase (SOD) after excitotoxic injury to the immature rat brain by using a recently constructed modular protein vector for non-viral gene delivery termed NLSCt. For this purpose, animals were injected with the NLSCt vector carrying the Cu/Zn SOD or the control GFP transgenes 2 hours after intracortical N-methyl-D-aspartate (NMDA) administration, and daily functional evaluation was performed. Moreover, 3 days after, lesion volume, neuronal degeneration and nitrotyrosine immunoreactivity were evaluated.  相似文献   
93.
In the last decades, the development of interconnectivity, pervasive systems, citizen sensors, and Big Data technologies allowed us to gather many data from different sources worldwide. This phenomenon has raised privacy concerns around the globe, compelling states to enforce data protection laws. In parallel, privacy-enhancing techniques have emerged to meet regulation requirements allowing companies and researchers to exploit individual data in a privacy-aware way. Thus, data curators need to find the most suitable algorithms to meet a required trade-off between utility and privacy. This crucial task could take a lot of time since there is a lack of benchmarks on privacy techniques. To fill this gap, we compare classical approaches of privacy techniques like Statistical Disclosure Control and Differential Privacy techniques to more recent techniques such as Generative Adversarial Networks and Machine Learning Copies using an entire commercial database in the current effort. The obtained results allow us to show the evolution of privacy techniques and depict new uses of the privacy-aware Machine Learning techniques.  相似文献   
94.
The synthesis of selenium derivatives of naturally occurring chiral molecules is becoming increasingly important in recent years. In this context, we describe herein an easy, straightforward synthetic route for the preparation of a series of chiral seleno-furanosides, starting from the readily available carbohydrate d-xylose. In addition, selected compounds were screened as inhibitors of the δ-aminolevulinate dehydratase (δ-ALA-D) enzyme. Diselenide 4 was found to reduce significantly the enzymatic activity, while seleno-furanoside 1a increased δ-ALA-D activity.  相似文献   
95.
The local single particle momentum is proposed as a localized‐electrons detector (LED) that provides a direct three‐dimensional representation of bonding interactions in molecules. It is given exclusively in terms of the electron density and its gradient. We show that the graphical representation of bonding interactions given by LED is consistent with the local curvatures of the electron density as given by the eigenvalues of the Hessian matrix, according to a local symmetry classification of the critical points here introduced. LED consistently complements the topological analysis of the electron density given by the quantum theory of atoms in molecules, by providing a graphical representation of the symmetry of the bonding interactions in molecular systems. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2418–2425, 2010  相似文献   
96.
The certification of glass-fibre reinforced plastic (GFRP) piping systems is regulated by normative standards in which test series of 10,000 h are required to estimate the residual properties at the end of the expected life (normally, 50 years). In this paper, the possibility to reduce the test duration, whilst maintaining an equivalent prediction of long-term properties, is discussed. Experimental results from standard test procedures conducted on GFRP pipes of four different types and respective data analysis support this possibility. The estimation error when using only data from shorter tests is consistently less than 10% if compared to the standard methods.  相似文献   
97.
Chlorophyll a and, in particular, bacteriochlorophyll a derivatives are promising candidates for photosensitizers in photodynamic therapy. The distribution of 21 (bacterio)chlorophyll derivatives among human blood plasma fractions was studied by iodixanol gradient ultracentrifugation and in situ absorption spectroscopy. Modifications of the natural pigments involved the central metal (Mg2+, Zn2+, Pd2+, none), the isocyclic ring (closed, open and taurinated), substituents at C-3 (vinyl, acetyl, 1-hydroxyethyl) and C-173 (phytyl ester, free acid). Cellular blood components bound only a small fraction of the pigments. Distribution among low-density lipoproteins (LDL), high-density lipoproteins (HDL) and high-density proteins (HDP) of the plasma was influenced as follows: (1) application in Cremophor® EL slightly altered pigment distribution by lipoprotein modification, (2) only very polar pigments with multiple hydrophilic substituents showed substantial HDP binding, (3) the presence of the esterifying alcohol at C-173 caused enrichment in LDL, this was more pronounced with bacteriochlorophylls than with chlorophylls, (4) substituents at C-3 had only little influence on the distribution, (5) Zn2+-complexes were enriched in HDL compared to Mg2+ and Pd2+ complexes, indicating specific binding of the former. Equilibration of pigments among the different fractions was largely complete within 3 h.  相似文献   
98.
99.
In the present work we report on a novel and fast protocol for accurate bottom-up protein quantification that overcomes the drawbacks of in-gel digestion and MALDI analysis, while maintaining their benefits. It relies on the following steps: (i) gel electrophoresis separation of proteins, (ii) fast in-gel protein digestion with trypsin, (iii) (18)O-labeling through the decoupled method, (iv) quantification through selected peptides previously chosen using the (18)O inverse labeling approach and that, finally, (v) it takes advantage of software specifically developed to select the peptides that will drive the quantification of the protein in an automated mode. We have accurately quantified the following six proteins: glycogen phosphorylase, BSA, ovalbumin, carbonic anhydrase, trypsin inhibitor, and α-lactalbumin. As a case study we have quantified the protein vitellogenin in plasma of Cyprinus carpio exposed to high levels of estrogens. The proposed new protocol was validated against the traditional ELISA method; both were found to provide comparable results (non-parametric Mann-Whitney U-test).  相似文献   
100.
The fulvene complexes [(η6-C5Me4CH2)Re(CO)2(R)] (1a, RI; 1b, RC6F5) react at the exocyclic methylene carbon with a vinylmagnesium bromide solution to produce the anionic species [(η5-C5Me4CH2CHCH2)Re(CO)2(R)]. Protonation with HCl at 0 °C produces the hydride complexes [trans-5-C5Me4CH2CHCH2)Re(CO)2(R)(H)] (2a, RI; 2b, RC6F5). Thermolysis of an hexane solution of the iodo-hydride (2a) under a CO atmosphere yields the complex [(η5-C5Me4CH2CHCH2)Re(CO)3] (3) and [Re(CO)5I] as by-product. Thermolysis of 2b produced three new products, mainly the chelated complex [(η52-C5Me4CH2CHCH2)Re(CO)2] (4) and complex 3, with a non-coordinated olefin group, in moderated yield, and traces of [Re(CO)5(C6F5)]. Thermolysis of an hexane solution of 2 in presence of an excess of PMe3, afforded the phosphine derivative [(η5-C5Me4CH2CHCH2)Re(CO)2(PMe3)] (5). All the complexes were characterized by IR, 1H, 13C and 31P NMR spectroscopies and mass spectrometry. The molecular structure of 4 has also been determined. The molecule exhibits a formal three-legged piano-stool structure, with two CO groups, and the third position corresponding to the η2-coordination of the propenyl side arm of the η5-C5Me4 ring.  相似文献   
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