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Annamaria Cattaneo Luisella Bocchio-Chiavetto Roberta Zanardini Eleonora Marchina Daniela Bellotti Elena Milanesi Stefania Moraschi Francesca Calabrese Sergio Barlati Marco Andrea Riva Massimo Gennarelli 《BMC neuroscience》2010,11(1):1-5
Background
Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which plays survival- and growth-promoting activity in neuronal cells and it is involved in cellular plasticity mechanisms as it controls activity dependent synaptic transmission. A functional polymorphism (Val66Met) in the pro-region of BDNF, which affects the intracellular trafficking of proBDNF has been associated with memory and cognitive deficits as well as to an increased susceptibility for several psychiatric disorders especially those with a neurodevelopmental origin. To date, no study has evaluated the influence of the Val66Met polymorphism on BDNF levels in a peripheral system that may reflect fetal neurodevelopment. Therefore we investigated in amniotic fluids (AF) obtained from 139 healthy women during 15-17 week of pregnancy, BDNF protein levels in correlation with the Val66Met polymorphism.Results
Interestingly we found a significant BDNF protein levels reduction in 55 Met carriers (Val/Met and Met/Met) (p = 0.002) as compared to 84 non carriers (Val/Val), and no effect of fetus gender, maternal age or gestation week on BDNF levels has been observed.Conclusion
These results, although explorative, indicate that during fetal life the Val66Met genotype might influences BDNF protein levels in AF supporting the involvement of this polymorphism in behavioral and functional brain individual differences in the adulthood. 相似文献144.
Annamaria Visco Cristina Scolaro 《International Journal of Polymer Analysis and Characterization》2018,23(4):354-361
Diode laser source was successfully employed for the fabrication of joints comprising nanocomposites of biomedical-grade UHMWPE and small amounts of carbon nanoparticles. The joint with 0.016?wt% of filler exhibited mechanical shear strength of 169N and a light-white color, close to the typical milk-white color of polyethylene. A morphological study of the welded area had been performed. The laser energy produced a thermal effect on the heat-altered zone, thereby smoothening out the surface at a depth of about 1.5?mm. Moreover, surface roughness decreased and the permeability of the joint to biological fluids was enhanced. 相似文献
145.
Water Molecules Gating a Photoinduced One‐Electron Two‐Protons Transfer in a Tyrosine/Histidine (Tyr/His) Model of Photosystem II
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Dr. Georgios Chararalambidis Dr. Shyamal Das Adelais Trapali Dr. Annamaria Quaranta Dr. Maylis Orio Dr. Zakaria Halime Dr. Pierre Fertey Dr. Régis Guillot Prof. Athanassios Coutsolelos Dr. Winfried Leibl Prof. Ally Aukauloo Dr. Marie Sircoglou 《Angewandte Chemie (International ed. in English)》2018,57(29):9013-9017
We investigate a biomimetic model of a TyrZ/His190 pair, a hydrogen‐bonded phenol/imidazole covalently attached to a porphyrin sensitizer. Laser flash photolysis in the presence of an external electron acceptor reveals the need for water molecules to unlock the light‐induced oxidation of the phenol through an intramolecular pathway. Kinetics monitoring encompasses two fast phases with distinct spectral properties. The first phase is related to a one‐electron transfer from the phenol to the porphyrin radical cation coupled with a domino two‐proton transfer leading to the ejection of a proton from the imidazole–phenol pair. The second phase concerns conveying the released proton to the porphyrin N4 coordinating cavity. Our study provides an unprecedented example of a light‐induced electron‐transfer process in a TyrZ/His190 model of photosystem II, evidencing the movement of both the phenol and imidazole protons along an isoenergetic pathway. 相似文献
146.
Ricerche di Matematica - The Cauchy problem for a class of hyperbolic operators with triple characteristics is analyzed. Some a priori estimates in Sobolev spaces with negative indexes are proved.... 相似文献
147.
Dimethyl carbonate (DMC) is used as an alternative and eco‐friendly solvent for selective cyclocarbonylation reactions of allyl phenol derivatives for the synthesis of lactones; in some cases, depending on the reaction condition, DMC behaves as a ring‐opening reagent producing methoxycarbonyl compounds. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
148.
Paola Marchese Annamaria Celli Maurizio Fiorini 《Journal of Polymer Science.Polymer Physics》2004,42(15):2821-2832
Poly(butylene terephthalate) (PBT)/polycarbonate (PC) samples, prepared via reactive blending in the presence of Ti‐ and Sm‐based catalysts, resulted in block copolymers whose block length decreased as the mixing time increased. A single homogeneous amorphous phase occurred when the blocks had monomeric sequences shorter than 10 units. Otherwise, a crystalline phase of PBT developed. Also, in poly(ethylene terephthalate) (PET)/PC blends previously studied, the miscibility was strictly correlated with the crystallizability of the system. Therefore, the miscibility of the PBT/PC and PET/PC blends was compared with respect to the tendency of the PBT and PET blocks to crystallize under isothermal conditions. The crystallization rate of the PBT/PC copolymers was faster than that of the PET/PC copolymers with similar block lengths. Accordingly, the minimum crystallizable sequence length of the PBT blocks was shorter than that of the PET blocks (18 vs 31 monomeric unit sequences). This behavior was interpreted as an effect of the more flexible PBT units, which had a greater tendency to fold and crystallize than the PET units. Therefore, PBT, the blocks of which tended to crystallize even if they were very short and phase‐separated, was characterized by a poorer compatibility with PC than that of PET. As a result, the block size had a fundamental role in determining the crystallizability and, therefore, phase behavior of the semicrystalline block copolymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2821–2832, 2004 相似文献
149.
We derive the analog of the large N Gross‐Taylor holomorphic string expansion for the refinement of q‐deformed Yang‐Mills theory on a compact oriented Riemann surface. The derivation combines Schur‐Weyl duality for quantum groups with the Etingof‐Kirillov theory of generalized quantum characters which are related to Macdonald polynomials. In the unrefined limit we reproduce the chiral expansion of q‐deformed Yang‐Mills theory derived by de Haro, Ramgoolam and Torrielli. In the classical limit , the expansion defines a new β‐deformation of Hurwitz theory wherein the refined partition function is a generating function for certain parameterized Euler characters, which reduce in the unrefined limit to the orbifold Euler characteristics of Hurwitz spaces of holomorphic maps. We discuss the geometrical meaning of our expansions in relation to quantum spectral curves and β‐ensembles of matrix models arising in refined topological string theory. 相似文献
150.
Jessica Clavadetscher Dr. Eugenio Indrigo Dr. Sunay V. Chankeshwara Dr. Annamaria Lilienkampf Prof. Mark Bradley 《Angewandte Chemie (International ed. in English)》2017,56(24):6864-6868
Transition metals have been successfully applied to catalyze non-natural chemical transformations within living cells, with the highly efficient labeling of subcellular components and the activation of prodrugs. In vivo applications, however, have been scarce, with a need for the specific cellular targeting of the active transition metals. Here, we show the design and application of cancer-targeting palladium catalysts, with their specific uptake in brain cancer (glioblastoma) cells, while maintaining their catalytic activity. In these cells, for the first time, two different anticancer agents were synthesized simultaneously intracellularly, by two totally different mechanisms (in situ synthesis and decaging), enhancing the therapeutic effect of the drugs. Tumor specificity of the catalysts together with their ability to perform simultaneous multiple bioorthogonal transformations will empower the application of in vivo transition metals for drug activation strategies. 相似文献