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排序方式: 共有8576条查询结果,搜索用时 15 毫秒
1.
Patricia Seoane-Collazo Amparo Romero-Pic Eva Rial-Pensado Laura Liares-Pose nxela Estvez-Salguero Johan Fern Rubn Nogueiras Carlos Diguez Miguel Lpez 《International journal of molecular sciences》2021,22(4)
Several studies have reported that nicotine, the main bioactive component of tobacco, exerts a marked negative energy balance. Apart from its anorectic action, nicotine also modulates energy expenditure, by regulating brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. These effects are mainly controlled at the central level by modulation of hypothalamic neuropeptide systems and energy sensors, such as AMP-activated protein kinase (AMPK). In this study, we aimed to investigate the kappa opioid receptor (κOR)/dynorphin signaling in the modulation of nicotine’s effects on energy balance. We found that body weight loss after nicotine treatment is associated with a down-regulation of the κOR endogenous ligand dynorphin precursor and with a marked reduction in κOR signaling and the p70 S6 kinase/ribosomal protein S6 (S6K/rpS6) pathway in the lateral hypothalamic area (LHA). The inhibition of these pathways by nicotine was completely blunted in κOR deficient mice, after central pharmacological blockade of κOR, and in rodents where κOR was genetically knocked down specifically in the LHA. Moreover, κOR-mediated nicotine effects on body weight do not depend on orexin. These data unravel a new central regulatory pathway modulating nicotine’s effects on energy balance. 相似文献
2.
Quality enhancement of the abundant under‐valued crustacean,lobster krill (Munida spp.), during its chilled storage 下载免费PDF全文
Bibiana García‐Soto José M. Miranda Jorge Barros‐Velázquez Santiago P. Aubourg 《International Journal of Food Science & Technology》2015,50(3):708-716
Lobster krill (Munida genus) represents an under‐valued crustacean frequently caught on European fishing banks. In this work, its sensory, microbiological and biochemical qualities were evaluated during chilled storage. Additionally, the effects of a prestorage antimelanosic treatment consisting of soaking in sodium metabisulphite (SMB) solutions at two different concentrations (0.25% and 0.75%) were also studied. SMB prestorage treatment provided lobster specimens that still exhibited acceptable sensory quality after 10 days of storage, while control specimens were unacceptable at that time. SMB treatment also resulted in a significant (P < 0.05) inhibition of microbial growth, mainly of Enterobacteriaceae, psychrotrophes and proteolytic bacteria. Low lipid oxidation levels were observed for all batches; however, a significantly higher (P < 0.05) retention of polyunsaturated fatty acids was found in SMB‐treated lobster, especially in the 0.75% SMB batch. The results presented here open the way to the potential commercialisation of currently under‐utilised lobster krill as a chilled product. 相似文献
3.
ABSTRACTThis paper deals with asymptotic stabilisation of a class of nonlinear input-delayed systems via dynamic output feedback in the presence of disturbances. The proposed strategy has the structure of an observer-based control law, in which the observer estimates and predicts both the plant state and the external disturbance. A nominal delay value is assumed to be known and stability conditions in terms of linear matrix inequalities are derived for fast-varying delay uncertainties. Asymptotic stability is achieved if the disturbance or the time delay is constant. The controller design problem is also addressed and a numerical example with an unstable system is provided to illustrate the usefulness of the proposed strategy. 相似文献
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Pablo Salcedo-Abraira Sergio M.F.Vilela Artem A.Babaryk Maria Cabrero-Antonino Pedro Gregorio Fabrice Salles Sergio Navalon Hermenegildo Garcia Patricia Horcajada 《Nano Research》2021,14(2):450-457
A novel microporous two-dimensional(2D)Ni-based phosphonate metal-organic framework(MOF;denoted as IEF-13)has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational techniques.Structure resolution by single-crystal X-ray diffraction reveals that IEF-13 crystallizes in the triclinic space group Pi having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ligand.Remarkably,this material exhibits coordinatively unsaturated nickel(II)sites,free-P03H2and-P03H acidic groups,a C02accessible microporosity,and an exceptional thermal and chemical stability.Further,its in-deep optoelectronic characterization evidences a photoresponse suitable for photocatalysis.In this sense,the photocatalytic activity for challenging H2generation and overall water splitting in absence of any co-catalyst using UV-Vis irradiation and simulated sunlight has been evaluated,constituting the first report for a phosphonate-MOF photocatalyst.IEF-13 is able to produce up to 2,200 fimol of H2per gram using methanol as sacrificial agent,exhibiting stability,maintaining its crystal structure and allowing its recycling.Even more,170μmol of H2per gram were produced using IEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting,being this reaction limited by the 02reduction.The present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials. 相似文献
8.
Zhang Xi Wang Xianhai Zhao Hongke Ordóñez de Pablos Patricia Sun Yongqiang Xiong Hui 《Scientometrics》2019,119(3):1311-1344
Scientometrics - Altmetrics indices are increasingly applied to measure scholarly influence in recent years because they can reflect the influence of research outputs more timely comparing with... 相似文献
9.
Thandi Patricia Gumede 《乙烯基与添加剂工艺杂志》2021,27(3):469-484
This review paper deals with the overall crystallization behavior of polyethylene/wax blends as phase change materials (PCMs) for thermal energy storage with the determination of their thermal properties. The addition of molten wax to the polyethylenes decreases the crystallization and melting temperatures of the blends. However, incorporating fillers to the polyethylene/wax blends can either decrease or increase the crystallization and melting temperatures of the composites depending on the filler type. The normalized enthalpy values of linear low-density polyethylene showed no significant change when increasing the wax content. On the contrary, the normalized enthalpy values of the wax in the blends were lesser than that of pure wax and increased with increasing wax content. Since the wax in the blend had a lower crystallinity compared to pure wax, this influences its effectiveness as a PCM for thermal energy storage. The effect of different polyethylenes on the wax morphology gave rise to enhance phase separation when wax was blended to high-density polyethylene as compared to the other polyethylenes. On the contrary, the effect of various waxes on the morphology of polyethylene resulted in different morphologies due to the molecular weight of the wax used and the structure of the polyethylene chain. The addition of fillers to the polyethylene (PE)/wax samples resulted in enhanced phase separation. The overall isothermal crystallization rate and the equilibrium melting temperature of PEs in the PEs/wax blends were depressed by wax addition due to the wax dilution effect. 相似文献
10.
Cecilia Arriagada Viviana A. Cavieres Charlotte Luchsinger Alexis E. Gonzlez Vanessa C. Muoz Jorge Cancino Patricia V. Burgos Gonzalo A. Mardones 《International journal of molecular sciences》2020,21(22)
Protein trafficking is altered when normal cells acquire a tumor phenotype. A key subcellular compartment in regulating protein trafficking is the Golgi apparatus, but its role in carcinogenesis is still not well defined. Golgi phosphoprotein 3 (GOLPH3), a peripheral membrane protein mostly localized at the trans-Golgi network, is overexpressed in several tumor types including glioblastoma multiforme (GBM), the most lethal primary brain tumor. Moreover, GOLPH3 is currently considered an oncoprotein, however its precise function in GBM is not fully understood. Here, we analyzed in T98G cells of GBM, which express high levels of epidermal growth factor receptor (EGFR), the effect of stable RNAi-mediated knockdown of GOLPH3. We found that silencing GOLPH3 caused a significant reduction in the proliferation of T98G cells and an unexpected increase in total EGFR levels, even at the cell surface, which was however less prone to ligand-induced autophosphorylation. Furthermore, silencing GOLPH3 decreased EGFR sialylation and fucosylation, which correlated with delayed ligand-induced EGFR downregulation and its accumulation at endo-lysosomal compartments. Finally, we found that EGF failed at promoting EGFR ubiquitylation when the levels of GOLPH3 were reduced. Altogether, our results show that GOLPH3 in T98G cells regulates the endocytic trafficking and activation of EGFR likely by affecting its extent of glycosylation and ubiquitylation. 相似文献