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排序方式: 共有495条查询结果,搜索用时 571 毫秒
81.
Sara Nava Daniela Lisini Simona Frigerio Anna Bersano 《International journal of molecular sciences》2021,22(22)
Dendritic cells (DCs) are immune specialized cells playing a critical role in promoting immune response against antigens, and may represent important targets for therapeutic interventions in cancer. DCs can be stimulated ex vivo with pro-inflammatory molecules and loaded with tumor-specific antigen(s). Protocols describing the specific details of DCs vaccination manufacturing vary widely, but regardless of the employed protocol, the DCs vaccination safety and its ability to induce antitumor responses is clearly established. Many years of studies have focused on the ability of DCs to provide overall survival benefits at least for a selection of cancer patients. Lessons learned from early trials lead to the hypothesis that, to improve the efficacy of DCs-based immunotherapy, this should be combined with other treatments. Thus, the vaccine’s ultimate role may lie in the combinatorial approaches of DCs-based immunotherapy with chemotherapy and radiotherapy, more than in monotherapy. In this review, we address some key questions regarding the integration of DCs vaccination with multimodality therapy approaches for cancer treatment paradigms. 相似文献
82.
The transport of anthropogenic pollution by desert dust in the Eastern Mediterranean region was studied by analyzing major and trace element composition, organic species, and Pb isotope ratios in suspended dust samples collected in Jerusalem, Israel. Dust storms in this region are associated with four distinct synoptic conditions (Red Sea Trough (RS), Eastern High (EH), Sharav Cyclone (SC), and Cold Depression (Cyprus low, CD)) that carry dust mostly from North African (SC, CD, EH) and Arabian and Syrian (RS, EH) deserts. Substantial contamination of dust particles by Pb, Cu, Zn, and Ni is observed, while other elements (Na, Ca, Mg, Mn, Sr, Rb, REE, U, and Th) display natural concentrations. Sequential extraction of the abovementioned elements from the dust samples shows that the carbonate and sorbed fractions contain most of the pollution, yet the Al-silicate fraction is also contaminated, implying that soils and sediments in the source terrains of the dust are already polluted. We identified the pollutant sources by using Pb isotopes. It appears that before the beginning of the dust storm, the pollutants in the collected samples are dominated by local sources but with the arrival of dust from North Africa, the proportion of foreign pollutants increases. Organic pollutants exhibit behavior similar and complementary to that of the inorganic tracers, attesting to the importance of anthropogenic-pollutant addition en route of the dust from its remote sources. Pollution of suspended dust is observed under all synoptic conditions, yet it appears that easterly winds carry higher proportions of local pollution and westerly winds carry pollution emitted in the Cairo basin. Therefore, pollution transport by mineral dust should be accounted for in environmental models and in assessing the health-related effects of mineral dust. 相似文献
83.
Luis Alberto Madrigal‐Perez Melina Canizal‐Garcia Juan Carlos González‐Hernández Rosalia Reynoso‐Camacho Gerardo M. Nava Minerva Ramos‐Gomez 《Yeast (Chichester, England)》2016,33(6):227-234
The metabolic effects induced by resveratrol have been associated mainly with the consumption of high‐calorie diets; however, its effects with standard or low‐calorie diets remain unclear. To better understand the interactions between resveratrol and cellular energy levels, we used Saccharomyces cerevisiae as a model. Herein it is shown that resveratrol: (a) decreased cell viability in an energy‐dependent manner; (b) lessening of cell viability occurred specifically when cells were under cellular respiration; and (c) inhibition of oxygen consumption in state 4 occurred at low and standard energy levels, whereas at high energy levels oxygen consumption was promoted. These findings indicate that the effects of resveratrol are dependent on the cellular energy status and linked to metabolic respiration. Importantly, our study also revealed that S. cerevisiae is a suitable and useful model to elucidate the molecular targets of resveratrol under different nutritional statuses. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
84.
Daniela Lisini Sara Lettieri Sara Nava Giulia Accordino Simona Frigerio Chandra Bortolotto Andrea Lancia Andrea Riccardo Filippi Francesco Agustoni Laura Pandolfi Davide Piloni Patrizia Comoli Angelo Guido Corsico Giulia Maria Stella 《International journal of molecular sciences》2021,22(16)
Malignant Pleural Mesothelioma (MPM) is a rare and aggressive neoplasm of the pleural mesothelium, mainly associated with asbestos exposure and still lacking effective therapies. Modern targeted biological strategies that have revolutionized the therapy of other solid tumors have not had success so far in the MPM. Combination immunotherapy might achieve better results over chemotherapy alone, but there is still a need for more effective therapeutic approaches. Based on the peculiar disease features of MPM, several strategies for local therapeutic delivery have been developed over the past years. The common rationale of these approaches is: (i) to reduce the risk of drug inactivation before reaching the target tumor cells; (ii) to increase the concentration of active drugs in the tumor micro-environment and their bioavailability; (iii) to reduce toxic effects on normal, non-transformed cells, because of much lower drug doses than those used for systemic chemotherapy. The complex interactions between drugs and the local immune-inflammatory micro-environment modulate the subsequent clinical response. In this perspective, the main interest is currently addressed to the development of local drug delivery platforms, both cell therapy and engineered nanotools. We here propose a review aimed at deep investigation of the biologic effects of the current local therapies for MPM, including cell therapies, and the mechanisms of interaction with the tumor micro-environment. 相似文献
85.
We explore the phase behavior of Helium films on two variants of graphene: graphane (graphene coated with H, denoted GH) and graphene–fluoride (GF). A semiempirical interaction with these substrates is used in T=0 K Path Integral Ground State and finite temperature Path Integral Monte Carlo simulations. We predict that 4He forms anisotropic fluid states at low coverage. This behavior differs qualitatively from that on graphite because of the different surface composition, symmetry and spacing of the adsorption sites. The 4He ground state on both substrates is thus a self-bound anisotropic superfluid with a superfluid fraction ρ s /ρ lower than 1 due to the corrugation of the adsorption potential. In the case of GF such corrugation is so large that ρ s /ρ=0.6 at T=0 K and the superfluid is essentially restricted to move in a multiconnected space, along the bonds of a honeycomb lattice. We predict a superfluid transition temperature T? 0.25 (1.1) K for 4He on GF (GH). We have studied the elementary excitation spectrum of 4He on GF at equilibrium density finding a phonon–maxon–roton dispersion relation that is strongly anisotropic in the roton region. We conclude that these new platforms for adsorption studies offer the possibility of studying novel superfluid phases of quantum condensed matter. 相似文献
86.
Moshe Dayan 《Journal of Superconductivity and Novel Magnetism》2013,26(3):575-587
Here, I extend my last work about the origin of the pseudogaps in underdoped cuprates (Dayan in arXiv:1011.3206 cond-mat, 2010) to include the mechanism of superconductivity. This is done by adapting the formalism of the double correlations in systems with nested Fermi surfaces to the semi one-dimensional system of strings of holes. It is proposed that magnetic interaction is crucial for the establishment of the pseudogap and the high temperature superconductivity. It is shown that superconductivity disturbs the completeness of the strings of holes, and creates fluctuations in them. This, in turn, reduces the magnetic interaction and the pseudogap order. 相似文献
87.
S.A. Macías-Sánchez R. Nava V. Hernández-Morales Y.J. Acosta-Silva B. Pawelec S.M. Al-Zahrani R.M. Navarro J.L.G. Fierro 《International Journal of Hydrogen Energy》2013
Cd1−xZnxS solid solutions (x = 0.05–0.3) supported on mesoporous silica SBA-16 substrate with 3D cubic structure were investigated for hydrogen production from water splitting under visible light. The influence of Zn concentration (x) in the Cd1−xZnxS solid solution and support morphology were investigated. The bare SBA-16 substrate was synthetized by the hydrothermal method whereas the Cd1−xZnxS photocatalysts were prepared by coprecipitation of metal sulfides from aqueous solutions of Cd2+ and Zn2+ using Na2S as precipitating agent. An attempt has been made to determine the photocatalyst structures using several techniques including elemental analysis, N2 adsorption–desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM), UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS) and Raman spectroscopy. Surface characterization of the samples by XPS indicates that Cd1−xZnxS nanoparticles are unevenly distributed on both external surface and within the pore network. An increase of the band gap energy with increasing Zn loading up to x = 0.2 in the Cd1−xZnxS solid solution was observed. As a consequence, H2 evolution increases gradually with an increase of the Zn loading in the photocatalysts from 0.05 to 0.2 wt% being the Cd0.8Zn0.2S/SBA-16 system the most active among the catalysts studied. The highest activity of this photocatalyst was explained in terms not only of its large band gap energy but also by the enhancement of the interaction between the particles of solid solution and the SBA-16 substrate. 相似文献
88.
Surface characterization of the transient products that precede chalcocite formation during chalcopyrite reduction was carried out. The experimental strategy employed in the present work consisted of the application of different potential pulses (fixed energetic conditions) on the surface of chalcopyrite electrodes in 1.7 M H2SO4. The chemical products formed at different potential pulses were characterized by cyclic voltammetry (CV) and XPS. Each electrogenerated species presented a specific voltammetric behavior and an XPS spectrum, in which the values of principal photoelectronic peak bond energies for Cu 2p3/2, Fe 2p3/2 and S 2p3/2 and the atomic concentrations were considered. Several potential intervals could be identified: in 0.115 ≥ Ecat ≥ −0.085 V vs. SHE, an intermediate copper sulfide is formed whose composition is between those of chalcopyrite and bornite, such as talnakhite. The reduction of this product occurs slowly, giving bornite at potentials less than −0.085 V. In the applied potential region −0.085 ≥ Ecat > −0.185 V, the bornite gradually decomposes causing the incomplete conversion to chalcocite. In the potential interval −0.185 > Ecat ≥ −0.285 V, energetic conditions are large enough to allow the immediate decomposition of bornite, forming chalcocite in a more quantitative manner. 相似文献
89.
90.