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Douglas Nam Chih-Wen Ni Amir Rezvan Jin Suo Klaudia Budzyn Alexander Llanos David G. Harrison Don P. Giddens Hanjoong Jo 《Journal of visualized experiments : JoVE》2010,(40)
Despite the well-known close association, direct evidence linking disturbed flow to atherogenesis has been lacking. We have recently used a modified version of carotid partial ligation methods [1,2] to show that it acutely induces low and oscillatory flow conditions, two key characteristics of disturbed flow, in the mouse common carotid artery. Using this model, we have provided direct evidence that disturbed flow indeed leads to rapid and robust atherosclerosis development in Apolipoprotein E knockout mouse [3]. We also developed a method of endothelial RNA preparation with high purity from the mouse carotid intima [3]. Using this mouse model and method, we found that partial ligation causes endothelial dysfunction in a week, followed by robust and rapid atheroma formation in two weeks in a hyperlipidemic mouse model along with features of complex lesion formation such as intraplaque neovascularization by four weeks. This rapid in vivo model and the endothelial RNA preparation method could be used to determine molecular mechanisms underlying flow-dependent regulation of vascular biology and diseases. Also, it could be used to test various therapeutic interventions targeting endothelial dysfunction and atherosclerosis in considerably reduced study duration.Download video file.(125M, mp4) 相似文献
203.
Yang D Cai S Liu H Guo X Li C Shang M Wang X Zhao Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,831(1-2):288-302
Buyang Huanwu decoction (BYHWD) is a widely used Chinese traditional compound medicine that has proved effective in treating cerebrovascular illnesses; however, its active substances have remained unknown. In this paper, serum chemistry and combined high-performance liquid chromatography (HPLC), photodiode-array detection and mass-spectrometry techniques were used to study the constituents of BYHWD from pig serum after oral administration. A total of 45 characteristic HPLC peaks were detected from serum containing drug. The chemical structures of nine of the peaks were tentatively elucidated as 7,3'-dihydroxy-4'-methoxyisoflavone-7-O-glucuronide (P1), 7-hydroxy-4'-methoxyisoflavone-7-O-glucuronide (P2), 7,2',4'-trihydroxy-3'-methoxyisoflavane-7-O-sulphate (P3), 3-hydroxy-9,10-dimethoxypterocarpan-3-O-glucuronide (P4), 7,2'-dihydroxy-3',4'-dimethoxyisoflavane-7-O-glucuronide (P5), 3-hydroxy-9,10-dimethoxypterocarpane-3-O-sulphate (P6), 4(1H)-quinolinone (P7 or P8), 4-hydroxyquinoline (P8 or P7) and oleic acid (P9). All of the identified peaks, with the exception of P9, were metabolites of the constituents of BYHWD in vivo. 相似文献
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Bolang Cheng Jianxiu Ma Gaoda Li Suo Bai Qi Xu Xin Cui Li Cheng Yong Qin Zhong Lin Wang 《Liver Transplantation》2020,10(27)
Although much effort has been put in the studies of weak in vivo microscale movements due to its importance, the real‐time, long‐time, and accurate monitoring is still a great challenge because of the complexity of the in vivo environment. Here, a new type of mechanically asymmetrical triboelectric nanogenerator with ultrashort working distance and high anti‐interference ability is developed to accurately and real‐timely monitor the microscopically weak movement of intestinal motility at low frequencies even around 0.3 Hz. The intestinal status after the glucose absorption, and physiological states in different times also have been monitored successfully in the complex in vivo environment with many kinds of interference and noises. This work gives a new self‐powered, long‐time and in vivo technical way for the real‐timely gastrointestinal motility monitoring, and contributes to the detection of every kind of gentle movements in various complex bio‐systems. 相似文献
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Shuo Wang Wenxin Shi Tang Tang Yuying Wang Liling Zhi Jinze Lv Ji Li 《Reviews in Environmental Science and Biotechnology》2017,16(1):1-13
Aerobic granular sludge (AGS) has recently attracted attention because of its excellent settling ability and treatment efficiency compared with traditional activated sludge. This review provides recent advances on the formation process of AGS and mainly analyzes the function of quorum sensing (QS) and cell signaling during AGS formation. QS and cell signaling play important roles in the formation of AGS. QS can accelerate the synthesis of extracellular polymeric substance (EPS) and increase microbial adhesion to the surface of AGS. Cell signaling can also promote the secretion of EPS and influence biofilm formation. Cyclic diguanylate (c-di-GMP), as a second messenger, acts an important role in granulation. C-di-GMP causes bacteria to adhere to each other and form a biofilm. Adding Ca2+ benefits bacterial growth and promotes c-di-GMP secretion. Adding Mn2+ reduces c-di-GMP content and triggers AGS disintegration. Finally, the review discusses the possible trends of AGS: QS and cell signaling can lay a theoretical foundation for the formation mechanism of AGS and would be of practical significance for its application in the future. 相似文献
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酒醅中精氨酸利用菌株的分离筛选及其对浓香型白酒中瓜氨酸积累的影响 总被引:2,自引:0,他引:2
【目的】分析浓香型白酒酒醅发酵过程中氨基甲酸乙酯前体物质瓜氨酸含量显著增加的原因,确定酒醅中能够利用精氨酸并积累瓜氨酸的微生物,为解析白酒中氨基甲酸乙酯的形成机制提供研究基础和理论依据。【方法】采用高通量筛选技术,从浓香型白酒酒醅中分离具有高精氨酸利用能力和高瓜氨酸积累特性的菌株,并通过基因型和表现型验证以及模拟窖内发酵验证它们对瓜氨酸积累的贡献。【结果】共筛选获得20株具有高精氨酸利用能力的菌株,其中Lactococcus garvieae LD3,Bacillus amyloliquefaciens BG5,Pediococcus acidilactici PH7和Staphylococcus pasteuri SH11具有较高的瓜氨酸生成能力,并可使酒醅中瓜氨酸含量显著增加。【结论】筛选获得的4类微生物均能够通过ADI途径代谢积累瓜氨酸,是导致酒醅瓜氨酸含量增加的原因。 相似文献