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Absorption properties and mechanism of trolline and veratric acid and their implication to an evaluation of the effective components of the flowers of Trollius chinensis

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Chinese Journal of Natural Medicines 2014年第9期12卷 700-704页

作者： liu Li-Jia WU xiu-Wen WANG Ru-Feng PENG Yu-Shuai YANG Xin liu jun-xiu School of Chinese Materia Medica Beijing University of Chinese Medicine Department of Otorhinolaryngology Peking University Third Hospital

AIM: To study the absorption properties and mechanism of two important components, trolline and veratric acid, from the flowers of Trollius chinensis, in order to better understand the contribution of these two compounds to the effectiveness of these flowers. METHOD: The human Caco-2 cell monolayer model was employed to study the transport of trolline and veratric acid from apical side(AP) to basal side(BL), and from BL to AP by determining the transport rates as the function of time and concentration and calculating apparent permeability coefficients(Papp). RESULTS: Trolline and veratric acid were transported across Caco-2 cell monolayer through different mechanisms in a concentration dependent *** was transported at a Papp level of 10-6 cm·s-1 with a Papp AP→BL/Papp BL→AP ratio of more than 1.8 or less than 0.8, while veratric acid was transported at a Papp level of 10-5 cm·s-1 with a Papp AP→BL/Papp BL→AP ratio of close to 1.0. CONCLUSION: Trolline is moderately absorbed through an associative mechanism involving active and passive transport, and veratric acid is well-absorbed mainly through passive diffusion. These factors should be taken into account when chemically assessing the pharmacodynamic material basis of the flowers of T. chinensis.

关键词： Trollius flowers moderately apparent permeability implication absorbed chemically Absorption monolayer

A perturbation method to the tent map based on Lyapunov exponent and its application

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Chinese Physics B 2015年第10期24卷 78-85页

作者：曹绿晨罗玉玲丘森辉刘俊秀 Guangxi Key Laboratory of Multi-source Information Mining & Security Faculty of Electronic EngineeringGuangxi Normal University School of Computing and Intelligent Systems University of Ulster

Perturbation imposed on a chaos system is an effective way to maintain its chaotic features. A novel parameter perturbation method for the tent map based on the Lyapunov exponent is proposed in this paper. The pseudo-random sequence generated by the tent map is sent to another chaos function - the Chebyshev map for the post processing. If the output value of the Chebyshev map falls into a certain range, it will be sent back to replace the parameter of the tent map. As a result, the parameter of the tent map keeps changing dynamically. The statistical analysis and experimental results prove that the disturbed tent map has a highly random distribution and achieves good cryptographic properties of a pseudo-random sequence. As a result, it weakens the phenomenon of strong correlation caused by the finite precision and effectively compensates for the digital chaos system dynamics degradation.

关键词： perturbation tent map Lyapunov exponent finite precision

膜反应器中镁铝复合氧化物催化乙醇与环氧乙烷的醚化

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现代化工 2008年第1期28卷 56-57页

作者：刘秀军潘兵天津工业大学材料科学与化学工程学院天津300160

采用连续式膜反应器,在镁铝复合氧化物催化剂的作用下,以乙醇和环氧乙烷为原料,合成了乙二醇乙醚。通过确定合适镁铝摩尔比的催化剂,考察不同的反应温度以及空时的影响,得到了在以Mg/Al摩尔比=3的镁铝复合氧化物作为催化剂,在反应温度11... 详细信息

采用连续式膜反应器,在镁铝复合氧化物催化剂的作用下,以乙醇和环氧乙烷为原料,合成了乙二醇乙醚。通过确定合适镁铝摩尔比的催化剂,考察不同的反应温度以及空时的影响,得到了在以Mg/Al摩尔比=3的镁铝复合氧化物作为催化剂,在反应温度110℃、空时为2h时,乙二醇乙醚的选择性可达82.96%。

关键词：膜反应器乙氧基化镁铝复合氧化物催化剂乙二醇乙醚

“训诂治史”的会通之学——杨联陞与“清华学派”

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山东社会科学 2010年第4期 13-19页

作者：刘秀俊山东大学文史哲研究院山东济南250100

"清华学派"是基于共同文化背景及共同工作学习环境而产生共同治学情趣的一个群体,其主要特征是:"会通古今"、"会通中西"、"会通文理"。清华学子杨联陞沐浴在这种博通与专精相结合的学术环境下,转益多师,亲炙陈寅恪、雷海宗、陶希圣、赵... 详细信息

"清华学派"是基于共同文化背景及共同工作学习环境而产生共同治学情趣的一个群体,其主要特征是:"会通古今"、"会通中西"、"会通文理"。清华学子杨联陞沐浴在这种博通与专精相结合的学术环境下,转益多师,亲炙陈寅恪、雷海宗、陶希圣、赵元任等先生的教导与督励之惠,吸收了当时史学风潮中最好的质素,走出了一条"训诂治史"的会通之路,致力于提升汉学研究水平,成为打入国际汉学界之第一人。

关键词：清华学派杨联陞训诂治史会通

A 65-year-old man with infratentorial diffuse encephalopathy and hydrocephalus

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Chinese Medical Journal 2011年第11期124卷 1758-1760页

作者： FENG Yan-qing GUO Ning liu jun-xiu LAI Rong CHEN Xi HUANG Fan Department of Neurology First Affiliated Hospital of Sun Yat-senUniversity Guangzhou Guangdong 510080 China

Tuberculous encephalopathy （TBE） is an important diagnosis in countries with a high prevalence of tuberculosis. TBE is a life-threatening condition but rarely reported in the modern literature. We reported a case of a man with extensive parenchymal lesions involving the brainstem and right cerebellar hemisphere that resolved after treatment. The clinical, laboratory and pathological features of this case are highlighted and the pathogenesis is discussed.

关键词： tuberculous encephalopathy hydrocephalus

Effect of Neuronal Excitability in Hippocampal CA1 Area on Auditory Pathway in a Rat Model of Tinnitus

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Chinese Medical Journal 2018年第16期131卷 1969-1974页

作者： Yu-Jing Ding Yu Song jun-xiu liu Ya-Li Du Li Zhu Fu-Rong Ma Department of Otorhinolaryngology Peking University Third Hospital Beijing 100191 China

Background： Tinnitus is a common disorder that causes significant morbidity; however, the neurophysiological mechanism is not yet fully understood. A relationship between tinnitus and limbic system has been reported. As a significant component of the l imbic system, the hippocampus plays an important role in various pathological processes, such as emotional disturbance, decreased learning ability, and deterioration of memory. This study was aimed to explore the role of the hippocampus in the generation oftinnitus by electrophysiological technology. Methods： A tinnitus model was established in rats through intraperitoneal injection of salicylate （SA）. Subsequently, the spontaneous firing rate （SFR） of neurons in the hippocampal CAI area was recorded with in vivo multichannel recording technology to assess changes in excitability induced by SA. To investigate the effect of excitability changes ofhippocampus on the auditory pathway, the hippocampus was electrically stimulated and neural excitability in the auditory cortex （AC） was monitored. Results： Totally 65 neurons in the hippocampal CAI area were recorded, 45 from the SA group （n = 5）, and 20 from the saline group （n = 5）. Two hours after treatment, mean SFR of neurons in the hippocampal CA1 area had significantly increased from 3.06 ± 0.36 Hz to 9.18 ±1.30 Hz in the SA group （t = -4.521, P 〈 0.05）, while no significant difference was observed in the saline group （2.66 ± 0.36 Hz vs. 2.16 ± 0.36 Hz, t = 0.902, P 〉 0.05）. In the AC, 79.3% （157/198） of recorded neurons showed responses to electrical stimulation of the hippocampal CA1 area. Presumed pyramidal neurons were excited, while intermediate neurons were inhibited after electrical stimulation of the hippocampus. Conclusions： The study shows that the hippocampus is excited in SA-induced tinnitus, and stimulation of hippocampus could modulate neuronal excitability of the AC. The hippocampus is involved in tinnitus and may also have a regulatory effect on the neu

关键词： Auditory Cortex Electrical Stimulation Hippocampus Neuronal Excitability Tinnitus

Change of extracellular ascorbic acid in the brain cortex following ice water vestibular stimulation： an on-line electrochemical detection coupled with in vivo microdialysis sampling for guinea pigs

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Chinese Medical Journal 2008年第12期121卷 1120-1125页

作者： ZHANG Na liu jun-xiu MA Fu-rong YU Li-sheng LIN Yu-qing liu Kun MAO Lan-qun Department of Otorhinolaryngology Peking University Third Hospital Beijing 100083 China Department of Otorhinolaryngology Peking University People's Hospital Beijing 100044 China Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Background Ascorbic acid （AA） represents one of the most important enzyme co-factors, antioxidants and neuromodulators and plays an important role in the cerebral system. Increasing evidence has suggested that AA could treat certain kinds of vertigo diseases such as Meniere＇s disease. To elucidate the neurochemical functions associated with AA in vertigo, the change of extracellular AA in the brain cortex following caloric vestibular stimulation （CVS） was evaluated.Methods An on-line electrochemical detection was coupled with in vivo microdialysis to continuously monitor the change of extracellular AA in the primary somatosensory （SI） area of guinea pigs following a caloric vestibular stimulation. Sixteen guinea pigs were divided into three groups, i.e., experimental group with irrigation of the ear canal with ice water （0℃）（n=-8）, and two control groups, one with irrigation of the ear canal with warm water （38℃）（n=-4） and the other with irrigation of the auricle with ice water （n=-4）.Results In the experimental group, the ice water irrigation of the left external ear canal induced a horizontal nystagmus towards the right side lasting about 45 seconds. No nystagmus was induced by warm water irrigation of the external ear canal or by ice water irrigation of the auricle. The extracellular AA concentration significantly increased following the ice water vestibular stimulation, reaching a maximum of （130±20）% （n=8） of the basal dialysate level （2.61±0.92） μmol/L （n=8）, lasting at least for an hour. AA level did not change distinctly after the irrigation of the left external ear canal with warm water or the irriclation of the auricle with ice water.Conclusions The concentration of extracellular AA in the brain cortex of the SI area increased following the ice water vestibular stimulation. This demonstration may be useful for the investigation of the neurochemical processes associated with AA in the process of vertigo.

关键词： ascorbic acid caloric vestibular stimulation primary somatosensory area in vivo microdialysis on-line electrochemical detection

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基于最小二乘法的边坡稳定性分析

岩土力学 2012年第6期33卷 1724-1729页

作者：贺建清刘秀军湖南科技大学湖南省普通高等学校土木工程施工过程与质量安全控制重点实验室湖南湘潭411201

利用经典土压力理论设定合理土条推力线范围,根据静力平衡及力矩平衡条件建立以条块界面安全系数Fv为变量的线性超定方程组,应用MATLAB软件基于最小二乘方法对此方程组求解,依据极大值原理及合理性条件:Fv≥Fs,最终获得边坡整体安全系... 详细信息

利用经典土压力理论设定合理土条推力线范围,根据静力平衡及力矩平衡条件建立以条块界面安全系数Fv为变量的线性超定方程组,应用MATLAB软件基于最小二乘方法对此方程组求解,依据极大值原理及合理性条件:Fv≥Fs,最终获得边坡整体安全系数Fs。经算例验证得出如下结论:当条块界面与条块整体安全系数相等时,边坡抗剪能力发挥最大;安全系数随推力线位置的升高而减小,但影响并不大;由于考虑了极大值原理,该法求得的安全系数略微偏大于其他方法。

关键词：最小二乘法边坡稳定性分析线性方程组

Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

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Chinese Medical Journal 2007年第2期120卷 120-124页

作者： MA Fu-rong liu jun-xiu LI Xue-pei MAO Jian-jun ZHANG Qun-dan JIA Hong-bo MAO Lan-quan ZHAO Rui Department of Otorhinolaryngology Peking University Third Hospital Beijing 100083 China Institue of Chemistry Chinese Academy of Sciences Beijing 100080 China Institue of Aviation Medicine Beijing 100036 China

Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei （MVN） receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin （5-hydroxytryptamine, 5-HT） release in the MVN during the period of vertigo induced by caloric stimulation. Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water （n=6）, ice water （n=6） and 37℃ water （n=4）, and the groups of irrigation of the auricle with hot water （n=-4） and ice water （n=4）, according to different caloric vestibular stimulation. We examined the animal＇s caloric nystagmus with a two-channel electronystagmographic recorder （ENG）, and meanwhile examine serotonin （5-hydroxytryptamine, 5-HT） level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water （44℃） irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

关键词： caloric stimulation vertigo media vestibular nuclei 5-hydroxytryptamine microdialysis