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154.
Yu-Young Lee Ming Wang Yurim Son Eun-Ju Yang Moon-Seok Kang Hyun-Joo Kim Hyung-Seok Kim Jihoon Jo 《Molecules (Basel, Switzerland)》2021,26(20)
Memory deterioration in Alzheimer’s disease (AD) is thought to be underpinned by aberrant amyloid β (Aβ) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3β (p-GSK3β-S9) and cleaved caspase 3, which are involved in Aβ-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline. 相似文献
155.
Junzhi Yao David Y. Son 《Journal of polymer science. Part A, Polymer chemistry》1999,37(20):3778-3784
A new organosilicon hyperbranched oligomer has been prepared that contains both double bonds and silyl hydride groups. The monomer is prepared via the hydrosilylation of propargyl chloride with methyldichlorosilane in the presence of a platinum catalyst. The product is a mixture resulting from both α- and β-addition. Treatment of the monomer mixture with magnesium results in the formation of a hyperbranched oligomer, which is then treated with LiAlH4. Control of monomer addition speed to the magnesium is critical in order to keep head-head coupling low. The resulting oligomer is air- and water-stable, and has an average degree of polymerization of 8. This material gives a char yield of 24% but after crosslinking with platinum catalyst, the char yield increases to 69%. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3778–3784, 1999 相似文献
156.
Seyeon Oh Chang Hu Choi Bae-Jin Lee Joung-Hyun Park Kuk-Hui Son Kyunghee Byun 《Molecules (Basel, Switzerland)》2021,26(23)
It is well known that oxidative stress induces muscle atrophy, which decreases with the activation of Nrf2/HO-1. Fermented oyster extracts (FO), rich in γ-aminobutyric acid (GABA) and lactate, have shown antioxidative effects. We evaluated whether FO decreased oxidative stress by upregulating Nrf2/HO-1 and whether it decreased NF-κB, leading to decreased IL-6 and TNF-α. Decreased oxidative stress led to the downregulation of Cbl-b ubiquitin ligase, which increased IGF-1 and decreased FoxO3, atrogin1, and Murf1, and eventually decreased muscle atrophy in dexamethasone (Dexa)-induced muscle atrophy animal model. For four weeks, mice were orally administered with FO, GABA, lactate, or GABA+Lactate, and then Dexa was subcutaneously injected for ten days. During Dexa injection period, FO, GABA, lactate, or GABA+Lactate were also administered, and grip strength test and muscle harvesting were performed on the day of the last Dexa injection. We compared the attenuation effect of FO with GABA, lactate, and GABA+lactate treatment. Nrf2 and HO-1 expressions were increased by Dexa but decreased by FO; SOD activity and glutathione levels were decreased by Dexa but increased by FO; NADPH oxidase activity was increased by Dexa but decreased by FO; NF-κB, IL-6, and TNF-α activities were increased by Dexa were decreased by FO; Cbl-b expression was increased by Dexa but restored by FO; IGF-1 expression was decreased by Dexa but increased by FO; FoxO3, Atrogin-1, and MuRF1 expressions were increased by Dexa but decreased by FO. The gastrocnemius thickness and weight were decreased by Dexa but increased by FO. The cross-sectional area of muscle fiber and grip strength were decreased by Dexa but increased by FO. In conclusion, FO decreased Dexa-induced oxidative stress through the upregulation of Nrf2/HO-1. Decreased oxidative stress led to decreased Cbl-b, FoxO3, atrogin1, and MuRF1, which attenuated muscle atrophy. 相似文献
157.
Meccanica - In this paper, the isogeometric cable elements based on B-spline curves are developed for the static analysis of cable structures under conservative static loads. For this, the... 相似文献
158.
We report the direct observation of 1D and 2D nanostructures of cobalt dipyrromethene trimer complexes adsorbed on a highly oriented pyrolytic graphite surface using scanning tunneling microscopy (STM). STM images showed two types of ordered structures coexisting on the surface: long 1D molecular chains isolated on the terraces, and 2D hexagonal patterns confined by a 1D chain and/or a graphite step edge. These 1D and 2D structures are attributed to ‘edge-on’ and ‘face-on’ complex alignments on the surface, respectively. In both configurations, substrate-mediated molecule-molecule interactions may play a significant role in stabilizing the nanostructures. 相似文献
159.
Colloidal cupric oxide (CuO) nanoparticles were formed by using a colloid-thermal synthesis process. X-ray diffraction patterns, transmission electron microscopy (TEM) images, high-resolution TEM images, and X-ray energy dispersive spectrometry profiles showed that the colloidal CuO nanoparticles were formed. The optical band-gap energy of CuO nanoparticles at 300 K, as determined from the absorbance spectrum, was 3.63 eV. A photoluminescence spectrum at 300 K showed that a dominant emission peak appeared at the blue region. X-ray photoelectron spectroscopy profiles showed that the O 1s and the Cu 2p peaks corresponding to the CuO nanoparticles were observed. 相似文献
160.
The 3D bioplotter, which is one of the rapid-prototyping systems, enables us to produce the design-based scaffolds which could
control good mechanical properties and pore structures for mimicking human organs. Although the plotting system has several
advantages to fabricate a variety of designed scaffolds, the main disadvantage of scaffolds fabricated by the system is that
the strand surfaces are too smooth and tend to discourage initial cell attachment within the scaffolds. To overcome the problem,
we suggest a new 3D plotting method supplemented by piezoelectric vibration system for fabricating scaffolds that have hierarchical
surface structures, which increase the surface roughness of the scaffold without any additional chemical process. The surface-modified
3D scaffold exhibited various positive qualities including enhanced compressive modulus and improved initial cell attachment
and proliferation. Cell culturing results demonstrated that the interactions between chondrocytes and the scaffold were much
more favorable than those between the cells and conventionally plotted 3D scaffolds. This process provides a feasible new
technique for fabricating high-quality 3D scaffolds for tissue engineering applications. 相似文献