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11.
Seyeon Oh Hyoung Moon Kim Sosorburam Batsukh Hye Jin Sun Taehui Kim Donghwan Kang Kuk Hui Son Kyunghee Byun 《International journal of molecular sciences》2022,23(16)
During skin aging, the volume of subcutaneous adipose tissue (sWAT) and the adipogenesis potential of adipose-derived stem cells (ASCs) decrease. It is known that the shortening of cilia length by pro-inflammatory cytokines is related to the decreased adipogenic differentiation of ASCs via increase in Wnt5a/β-catenin. High-intensity focused ultrasound (HIFU) is known to upregulate heat shock proteins (HSP), which decrease levels of pro-inflammatory cytokines. In this study, we evaluated whether HIFU modulates the cilia of ASCs by upregulating HSP70 and decreasing inflammatory cytokines. HIFU was applied at 0.2 J to rat skin, which was harvested at 1, 3, 7, and 28 days. All results for HIFU-applied animals were compared with control animals that were not treated. HIFU increased expression of HSP70 and decreased expression of NF-κB, IL-6, and TNF-α in sWAT. HIFU decreased the expression of cilia disassembly-related factors (AurA and HDAC9) in ASCs. Furthermore, HIFU increased the expression of cilia assembly-related factors (KIF3A and IFT88), decreased that of WNT5A/β-catenin, and increased that of the adipogenesis markers PPARγ and CEBPα in sWAT. HIFU increased the number of adipocytes in the sWAT and the thickness of sWAT. In conclusion, HIFU could selectively increase sWAT levels by modulating the cilia of ASCs and be used for skin rejuvenation. 相似文献
12.
Joon Seok Lee Hyun Geun Cho Jeong Yeop Ryu Eun Jung Oh Hyun Mi Kim Suin Kwak Seok-Jong Lee Jongmin Lee Sang Yub Lee Seung Huh Ji Yoon Kim Ho Yun Chung 《International journal of molecular sciences》2022,23(16)
Arteriovenous malformation (AVM) is characterized by high-flow blood vessels connecting arteries and veins without capillaries. This disease shows increased angiogenesis and a pathophysiological hypoxic environment in proximal tissues. Here, we analyzed the effects of hypoxia on angiogenesis in the endothelial cells (ECs) of AVM and normal tissues. ECs from human normal and AVM tissues were evaluated using immunocytochemistry with CD31. In vitro tube formation under hypoxia was tested in both ECs using Matrigel. The relative expression of angiogenesis-related genes was measured using real-time PCR. Under normoxia, CD31 was significantly higher in AVM ECs (79.23 ± 0.65%) than in normal ECs (74.15 ± 0.70%). Similar results were observed under hypoxia in AVM ECs (63.85 ± 1.84%) and normal ECs (60.52 ± 0.51%). In the tube formation test under normoxic and hypoxic conditions, the junction count and total vessel length were significantly greater in AVM ECs than normal ECs. Under both normoxia and hypoxia, the angiogenesis-related gene FSTL1 showed a significantly higher expression in AVM ECs than in normal ECs. Under hypoxia, CSPG4 expression was significantly lower in AVM ECs than in normal ECs. Accordingly, the angiogenic effect was increased in AVM ECs compared with that in normal ECs. These results provide a basic knowledge for an AVM treatment strategy. 相似文献
13.
Aiming at one of the decisive alternatives for long-term perspectives of the nuclear power, an integral and closed nuclear energy system concept is proposed; namely, the Advanced Molten-salt Break-even Inherently-safe Dual-missioning Experimental and Test Reactor (AMBIDEXTER) nuclear energy complex. This essentially comprises two mutually independent circuits of the radiation/material transport and the heat/energy conversion, centered at the integral reactor assembly, which enables one to utilize maximum benefits of nuclear energy under minimum risks of nuclear radiation. The entire reactor system resides in a thin and large Hastelloy vessel, the internal part of which is divided into a number of equipment compartments with neither connection pipings nor active valves necessary. As the reactor operates at very low FP inventory throughout its designed lifetime and there is no primary heat transport pipings outside the reactor vessel, significant release of radioactive materials due to any equipment failure should be incredible. The nuclear-thermalhydraulic characteristics of the molten ThF4–233UF4 fuel salt extend the self-sustainability of the AMBIDEXTER fuel cycle to enhance the resource security and safeguard transparency. While maintaining the break-even conversion ratio criterion, a flexible fuel management strategy using a certain choice of denaturants should improve its own proliferation-resistance characteristics. As the core technologies associated with developing the AMBIDEXTER concept are mostly available in commercialized forms at present, investigating the integral performance of the concept should be the prime research topic in ongoing 250 MWth prototype design studies. 相似文献
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Friction and wear behavior of continuous graphite fiber composites was studied for different fiber orientations against the sliding direction. The effect of fiber orientation on friction and wear of the composite and on deformation of the counterface was investigated experimentally. A pin on disk type testing machine was built and employed to generate friction and wear data. A graphite fiber composite plate was produced by the bleeder ply molding in an autoclave and machined into rectangular pin specimens with specific fiber orientations, i.e., normal, transverse, and longitudinal directions. Three different wear conditions were employed for two different periods of time, 24 and 48 hours. The wear track of the worn specimens and the metal counterface was examined and a scanning electron microscope (SEM) to observe the damaged fibers on the sliding surface of the specimen and wear film generation on the counterface. A wear mechanism of the continuous graphite fiber composite during sliding wear is proposed based on the experimental results. 相似文献
17.
Dong-Yong Hong Dong-Hun Lee Ji-Young Lee Eun-Chae Lee Sang-Won Park Man-Ryul Lee Jae-Sang Oh 《International journal of molecular sciences》2022,23(15)
The low-density-lipoprotein receptor (LDLr) removes low-density lipoprotein (LDL), an endovascular transporter that carries cholesterol from the bloodstream to peripheral tissues. The maintenance of cholesterol content in the brain, which is important to protect brain function, is affected by LDLr. LDLr co-localizes with the insulin receptor and complements the internalization of LDL. In LDLr deficiency, LDL blood levels and insulin resistance increase, leading to abnormal cholesterol control and cognitive deficits in atherosclerosis. Defects in brain cholesterol metabolism lead to neuroinflammation and blood–brain-barrier (BBB) degradation. Moreover, interactions between endoplasmic reticulum stress (ER stress) and mitochondria are induced by ox-LDL accumulation, apolipoprotein E (ApoE) regulates the levels of amyloid beta (Aβ) in the brain, and hypoxia is induced by apoptosis induced by the LDLr defect. This review summarizes the association between neurodegenerative brain disease and typical cognitive deficits. 相似文献
18.
In this letter, we present an event stream processing system that can evaluate a pattern query for a data sequence with predicates. We propose a pattern query language and develop a pattern query processing system. In our system, we propose novel techniques for run‐time aggregation and negation processing and apply our system to stream data generated from vehicles to monitor unusual driving patterns. 相似文献
19.
Ho Jin Ryu Byoung Oon Lee Seok Jin Oh Jun Hwan Kim Chan Bock Lee 《Journal of Nuclear Materials》2009,392(2):206-61
Diffusion couple tests of U-Zr or U-Zr-Ce alloys vs. ferritic martensitic steels such as HT9 or T91 were carried out in order to evaluate the performance of the diffusion barrier candidates. Elemental metal foils of Zr, Nb, Ti, Mo, Ta, V and Cr were very effective in inhibiting interdiffusion between these fuels and steels. Eutectic melting between the fuels and steels was not observed in any of the diffusion couples using these diffusion barrier foils at annealing temperatures up to 800 °C. Among the metallic foils evaluated in this study, V and Cr exhibited the most promising performances as a diffusion barrier material for eliminating the fuel cladding chemical interaction problem. However, Zr, Nb and Ti showed an active interaction with the fuel mainly due to the large U solubility. 相似文献
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