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91.
A series of titanium oxides was prepared by using a surfactant-template method (STM) and used as a carrier for the sustained release of ibuprofen, which was chosen as a model drug. This STM provides an efficient route to TiO(2) matrices with both high surface area (when compared with those that were obtained by using traditional synthetic approaches) and well-defined mesoporous textures. Some parameters of the synthetic procedure were varied: pH value, surfactant, and thermal treatment. The physicochemical nature of the surface carriers were investigated by means of N(2) -physisorption measurements and FTIR spectroscopy. The effect of the amount of drug on the release kinetics was also investigated. The drug delivery was evaluated in vitro in four different physiological solutions (that simulated the gastrointestinal tract) to analyze the behavior of the TiO(2) -based systems if they were to be formulated as oral DDSs. Our optimized approach is a good alternative to the classical methods that are used to prepare efficient TiO(2) -based drug-delivery systems.  相似文献   
92.
Ain't got that swing(-out): The cyclopeptide isoDGR is emerging as a new αvβ3 integrin binding motif. Agreement between the results of computational and biochemical studies reveals that isoDGR-containing cyclopeptides are true αvβ3 integrin antagonists that block αvβ3 in its inactive conformation (see scheme). isoDGR-based ligands may give αvβ3 antagonists without paradoxical effects.  相似文献   
93.
Unless the radiolytic reducing species are neutralised or converted into oxidising species, an EB remediation system cannot be considered a true Advanced Oxidation Processes (AOP). A water/H2O2 system irradiated by UVC mercury lamps constitutes a widely used OH production method. Employing H2O2 in radiolysis as well, an enhancement of the oxidative efficiency of an EB treatment can be obtained. Pulse radiolysis measurements of an aerated aqueous/H2O2/KSCN system have been systematically undertaken to assess the optimal H2O2 concentration. By linearly fitting a competition kinetics relationship, it is found that the scavengeable extra-yield of OH is ΔG(OH)=0.24 μmol J?1 (R=0,9958), while the maximum experimental yield is measured G(OH)max=(0.52±0.02) μmol J?1 when [H2O2]=5–10 mM. Exceeding these concentrations the OH yield drops off.  相似文献   
94.
We study the long time behavior of a Brownian particle moving in an anomalously diffusing field, the evolution of which depends on the particle position. We prove that the process describing the asymptotic behavior of the Brownian particle has bounded (in time) variance when the particle interacts with a subdiffusive field; when the interaction is with a superdiffusive field the variance of the limiting process grows in time as t2γ−1, 1/2<γ<1. Two different kinds of superdiffusing (random) environments are considered: one is described through the use of the fractional Laplacian; the other via the Riemann-Liouville fractional integral. The subdiffusive field is modeled through the Riemann-Liouville fractional derivative.  相似文献   
95.
A series of titanium oxides was prepared by using a surfactant‐template method (STM) and used as a carrier for the sustained release of ibuprofen, which was chosen as a model drug. This STM provides an efficient route to TiO2 matrices with both high surface area (when compared with those that were obtained by using traditional synthetic approaches) and well‐defined mesoporous textures. Some parameters of the synthetic procedure were varied: pH value, surfactant, and thermal treatment. The physicochemical nature of the surface carriers were investigated by means of N2‐physisorption measurements and FTIR spectroscopy. The effect of the amount of drug on the release kinetics was also investigated. The drug delivery was evaluated in vitro in four different physiological solutions (that simulated the gastrointestinal tract) to analyze the behavior of the TiO2‐based systems if they were to be formulated as oral DDSs. Our optimized approach is a good alternative to the classical methods that are used to prepare efficient TiO2‐based drug‐delivery systems.  相似文献   
96.
This paper consists of two results dealing with balanced metrics (in Donaldson terminology) on noncompact complex manifolds. In the first one we describe all balanced metrics on Cartan domains. In the second one we show that the only Cartan–Hartogs domain which admits a balanced metric is the complex hyperbolic space. By combining these results with those obtained in Loi and Zedda (Mathematische Annalen, 2011, to appear) we also provide the first example of complete, Kähler-Einstein and projectively induced metric g such that α g is not balanced for all α > 0.  相似文献   
97.
In this paper we are concerned with the optimal control problem consisting in minimizing the time for reaching (visiting) a fixed number of target sets, in particular more than one target. Such a problem is of course reminiscent of the famous “Traveling Salesman Problem” and brings all its computational difficulties. Our aim is to apply the dynamic programming technique in order to characterize the value function of the problem as the unique viscosity solution of a suitable Hamilton–Jacobi equation. We introduce some “external” variables, one per target, which keep in memory whether the corresponding target is already visited or not, and we transform the visiting problem in a suitable Mayer problem. This fact allows us to overcome the lacking of the Dynamic Programming Principle for the originary problem. The external variables evolve with a hysteresis law and the Hamilton–Jacobi equation turns out to be discontinuous  相似文献   
98.
Local branching is a general purpose heuristic method which searches locally around the best known solution by employing tree search. It has been successfully used in Mixed-Integer Programming where local branching constraints are used to model the neighborhood of an incumbent solution and improve the bound. We propose the integration of local branching in Constraint Programming (CP). This integration is not simply a matter of implementation, but requires a number of significant extensions. The original contributions of this paper are: the definition of an efficient and incremental bound computation for the neighborhood, a cost-based filtering algorithm for the local branching constraint and a novel diversification strategy that can explore arbitrarily far regions of the search tree w.r.t. the already found solutions. We demonstrate the practical value of local branching in CP by providing an extensive experimental evaluation on the hard instances of the Asymmetric Traveling Salesman Problem with Time Windows.  相似文献   
99.
The brain area which surrounds the frankly ischemic region is named the area penumbra. In this area, most cells are spared although their oxidative metabolism is impaired. area penumbra is routinely detected by immunostaining of a molecule named Heat Shock Protein 70 (HSP70). Within the area penumbra, autophagy-related proteins also increase. Therefore, in the present study, the autophagy-related microtubule-associated protein I/II-Light Chain 3 (LC3) was investigated within the area penumbra along with HSP70. In C57 black mice, ischemia was induced by permanent occlusion of the distal part of the middle cerebral artery. Immunofluorescence and electron microscopy show that LC3 and HSP70 are overexpressed and co-localize within the area penumbra in the same cells and within similar subcellular compartments. In the area penumbra, marked loss of co-localization of HSP70 and LC3-positive autophagy vacuoles, with lysosomal-associated membrane protein 1 (LAMP1) or cathepsin-D-positive lysosome vacuoles occurs. This study indicates that, within the area penumbra, a failure of autophagolysosomes depends on defective compartmentalization of LC3, LAMP1 and cathepsin-D and a defect in merging between autophagosomes and lysosomes. Such a deleterious effect is likely to induce a depletion of autophagolysosomes and cell clearing systems, which needs to be rescued in the process of improving neuronal survival.  相似文献   
100.
Natural products black cumin—Nigella sativa (N. sativa) and wild garlic—Allium ursinum (AU) are known for their potential role in reducing cardiovascular risk factors, including antracycline chemotherapy. Therefore, this study investigates the effect of N. sativa and AU water and methanolic extracts in a cellular model of doxorubicin (doxo)-induced cardiotoxicity. The extracts were characterized using Ultraviolet-visible (UV-VIS) spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, Liquid Chromatography coupled with Mass Spectrometry (LC-MS) and Gas Chromatography coupled with Mass Spectrometry (GC-MS) techniques. Antioxidant activity was evaluated on H9c2 cells. Cytosolic and mitochondrial reactive oxygen species (ROS) release was evaluated using 2′,7′-dichlorofluorescin-diacetate (DHCF-DA) and mitochondria-targeted superoxide indicator (MitoSOX red), respectively. Mitochondrial membrane depolarization was evaluated by flow cytometry. LC-MS analysis identified 12 and 10 phenolic compounds in NSS and AU extracts, respectively, with flavonols as predominant compounds. FT-IR analysis identified the presence of carbohydrates, amino acids and lipids in both plants. GC-MS identified the sulfur compounds in the AU water extract. N. sativa seeds (NSS) methanolic extract had the highest antioxidant activity reducing both intracellular and mitochondrial ROS release. All extracts (excepting AU methanolic extract) preserved H9c2 cells viability. None of the investigated plants affected the mitochondrial membrane depolarization. N. sativa and AU are important sources of bioactive compounds with increased antioxidant activities, requiring different extraction solvents to obtain the pharmacological effects.  相似文献   
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