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921.
Laily Rahmawati Sang Hee Park Dong Seon Kim Hwa Pyoung Lee Nur Aziz Chae Young Lee Seung A Kim Seok Gu Jang Dong Sam Kim Jae Youl Cho 《Molecules (Basel, Switzerland)》2022,27(1)
Prasiola japonica possesses several biological activities. However, reports on the anti-inflammatory activities and molecular mechanisms of its different solvent fractions remain limited. In this study, we investigated the potential anti-inflammatory activities of P. japonica ethanol extract (Pj-EE) and four solvent fractions of Pj-EE made with hexane (Pj-EE-HF), chloroform (Pj-EE-CF), butanol (Pj-EE-BF), or water (Pj-EE-WF) in both in vitro (LPS-induced macrophage-like RAW264.7 cells) and in vivo (carrageenan-induced acute paw edema mouse models) experiments. The most active solvent fraction was selected for further analysis. Various in vitro and in vivo assessments, including nitric oxide (NO), cytokines, luciferase assays, real-time polymerase chain reactions, and immunoblotting analyses were performed to evaluate the underlying mechanisms. In addition, the phytochemical constituents were characterized by Liquid chromatography-tandem mass spectrometry. In in vitro studies, the highest inhibition of NO production was observed in Pj-EE-CF. Further examination revealed that Pj-EE-CF decreased the expression of inflammation-related cytokines in LPS-induced RAW264.7 cells and suppressed subsequent AP-1-luciferase activity by inhibition of phosphorylation events in the AP-1 signaling pathway. Pj-EE-CF treatment also demonstrated the strongest reduction in thickness and volume of carrageenan-induced paw edema, while Pj-EE-BF showed the lowest activity. Furthermore, Pj-EE-CF also reduced gene expression and cytokines production in tissue lysates of carrageenan-induced paw edema. These findings support and validate the evidence that Pj-EE, and especially Pj-EE-CF, could be a good natural source for an anti-inflammatory agent that targets the AP1 pathway. 相似文献
922.
923.
为了探测图像中的肤色像素,提出了一种新的方法-支持向量机(SVM:Support Vector Machine)方法.它是一种基于肤色的非特定人的面部定位方法,是非接触人机交互技术和机器视觉中的一个重要内容.实验结果表明,采用支持向量机方法较传统人工神经网络方法不仅有更高的探测准确性,而且具有更好的推广性能.由于SVM采用结构风险最小化(SRM:Structural Risk Minimization)准则,在最小化训练误差(经验风险)的同时,尽量缩小模型预测误差的上界,从而使模型有更好的泛化能力. 相似文献
924.
D形光纤Bragg光栅弯曲灵敏度的理论和实验研究 总被引:2,自引:1,他引:1
用材料力学理论分析了D形光纤Bragg光栅(D-shaped fiber Bragg grating,D-FBG)以及常规光纤Bragg光栅由弯曲引起的轴向应变,得到了光栅Bragg波长漂移的弯曲敏感特性.实验结果和理论计算结果基本相符.与常规FBG相比,该D-FBG的弯曲灵敏度要高近80倍.因此D-FBG可以直接应用于弯曲形变的测量,以及间接应用于压力、加速度等物理量的测量.理论分析和实验结果对采用该类型光纤光栅的器件和传感系统的设计具有参考意义. 相似文献
925.
理论研究电流注入对垂直腔面发射激光器多横模行为的影响 总被引:1,自引:0,他引:1
从包含时空变量的速率方程出发,针对弱折射率导引垂直腔面发射激光器(VCSELs),利用空间积分法分析了典型电注入参数对VCSELs多横模行为的影响,在不降低模型准确性的前提下提高了仿真效率。仿真结果表明,注入盘孔径和注入环越小、注入强度越低以及电流扩散越弱时,VCSELs更易实现单横模工作;反之,VCSELs高阶横模开始出现并呈现较强的模式竞争,引发了载流子空间烧孔效应,并导致基模强度降低。进一步得出,在环形注入方式下,高阶模式更容易出现且彼此间的竞争较盘形注入时强。 相似文献
926.
927.
928.
KBA显微镜是一种非轴对称、非共轴的掠入射成像系统。其结构复杂,调节精度要求很高,在实际成像实验操作中难以掌握其成像特性。利用光学设计软件模拟其成像,对系统的调节和成像分析提供有益的参考。利用光学设计软件ZEMAX模拟了KBA显微镜对点源的成像过程,给出了KBA显微镜成像系统的焦深约为1 mm,景深为50 mm左右。并且由模拟可知,掠入射角对成像的影响很大。对像素尺寸约10μm的探测设备,模拟得出KBA成像系统的空间分辨力上限为3μm左右。基于星光Ⅱ装置对周期为20μm的网格靶成像,获得了KBA显微镜较为清晰的X光图像。该项工作为进一步开展掠入射成像系统的研究奠定了基础。 相似文献
929.
930.
Dongjoon Lee Jong-Chan Park Keum Sim Jung Jiyeong Kim Ji Sung Jang Sunghoon Kwon Min Soo Byun Dahyun Yi Gihwan Byeon Gijung Jung Yu Kyeong Kim Dong Young Lee Sun-Ho Han Inhee Mook-Jung 《Experimental & molecular medicine》2022,54(1):61
The deposition of beta-amyloid (Aβ) in the brain precedes the onset of symptoms such as cognitive impairment in Alzheimer’s disease (AD); therefore, the early detection of Aβ accumulation is crucial. We previously reported the applicability of the QPLEXTM Alz plus assay kit for the prescreening of Aβ accumulation. Here, we tested the specific application of the kit in a large cohort of cognitively normal (CN) individuals of varying ages for the early detection of Aβ accumulation. We included a total of 221 CN participants with or without brain Aβ. The QPLEXTM biomarkers were characterized based on age groups (1st–3rd tertile) and across various brain regions with cerebral amyloid deposition. The 3rd tertile group (>65 years) was found to be the most suitable age group for the application of our assay kit. Receiver operating characteristic curve analysis showed that the area under the curve (AUC, discrimination power) was 0.878 with 69.7% sensitivity and 98.4% specificity in the 3rd tertile group. Additionally, specific correlations between biomarkers and cerebral amyloid deposition in four different brain regions revealed an overall correlation with general amyloid deposition, consistent with previous findings. Furthermore, the combinational panel with plasma Aβ1–42 levels maximized the discrimination efficiency and achieved an AUC of 0.921 with 95.7% sensitivity and 67.3% specificity. Thus, we suggest that the QPLEXTM Alz plus assay is useful for prescreening brain Aβ levels in CN individuals, especially those aged >65 years, to prevent disease progression via the early detection of disease initiation.Subject terms: Alzheimer''s disease, Neural ageing, ELISA 相似文献