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Application of synchrotron source based DEI method in guinea pig cochleae imaging

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Progress in Natural Science:Materials International 2007年第1期17卷 59-67页

作者： YIN Hongxia, LIU Bo, GAO Xin, GAO Xiulai and LUO Shuqian ( college of Biomedical Engineering, capital university of medical sciences, {3. 100069, china Department of Anatomy, capital university of medical sciences, {3. 100069, china) college of Biomedical Engineering Capital University of Medical Sciences Beijing 100069 China Department of Anatomy Capital University of Medical Sciences Beijing 100069 China

Hard X-ray diffraction enhanced imaging (DEI), which is based on a synchrotron source and monochromator-analyzer-crystal system, is an effective method for imaging X-ray phase shift. Utilizing an analyzer crystal with high angular sensitivity of micro-radian, DEI can measure the transmitted, refracted and scattered X-rays when projecting onto a sample. It dramatically improves the contrast and spatial resolution of the resultant images. At the topography station of beijing Synchrotron Radiation Facilities (BSRF), we implemented DEI method in guinea pig cochleae imaging and acquired a series of DEI images. Based on these images, the apparent absorption and refraction images were calculated. The DEI images revealed the holistic spiral structures and inner details of guinea pig cochleae clearly, even including the structures at the cellular level, such as the static cilia of hairy cells and the limbus of Hansen cell. Due to the advantages of high contrast, high spatial resolution and distinct edge-enhanced effect, DEI method promises extensive applications in biology, medicine and clinic in the near future.

关键词： diffraction enhanced imaging hard X-ray imaging phase-contrast imaging cochlea micro-structure synchrotron source.

β2 Adrenergic receptor on T lymphocytes and its clinical implications

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Progress in Natural Science:Materials International 2009年第1期19卷 17-23页

作者： Xuelai Fan a,Yuedan Wang b,a Peking university,School of Pharmaceutical sciences,beijing 100083.{3. b Peking university,School of basic medical sciences,beijing 100083.{3. [a]Peking university School of Pharmaceutical Sciences Beijing 100083 China [b]Peking University School of Basic Medical Sciences Beijing 100083 China

Sustained complex cross-talk between the immune system and the nervous system plays a vital role in retaining homeostasis in a healthy *** of the central regulatory mechanisms involved is the existence and functions of β2-adrenergic receptors(β2AR) on T *** article reviews research progress made recently,including the expression of adrenergic receptors on T lymphocytes,the structure and intracellular pathways of β2AR,the activation of β2AR by either endogenous or exogenous agonists,and the effect of β2AR stimulation on T cells which alters T cell proliferation,differentiation,cytokine production and T-helper-mediated antibody ***,we discuss the roles of β2AR played in the pathogenesis and treatment of autoimmune diseases.

关键词： Neuroimmunology β2-adrenergic receptor T cell Autoimmune

Rheological Behavior of Epoxy Resin Concentrated Dispersions

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Chinese Chemical Letters 1999年第10期10卷 867-870页

作者： Zhen Zhong YANG Wei Wei WANG De Lu ZHAO Mao XU (1 Institute of Chemistry. The Chinese Academy of sciences, beijing 1000802 School of basic {3. Science. capital university of {3. Science, beijing 100054) Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China capital Univ Med Sci Sch Basic Med Sci Beijing 100054 Peoples R China

For the concentrated dispersions of epoxy resin prepared by phase inversion emulsification technique, the effects of solid content and temperature on the rheological behavior are studied. It is found that there exists reversible structural transition in concentrated dispersions subjected to shearing. The viscosity oscillation correlated with high viscoelasticity at lower stress is remarkable in highly concentrated dispersions. There exists storage modules overshot at higher stress during the dynamic stress time ramp test. This could provide some information on dynamics of structure changes during shear action. Besides, the effects of solid content and temperature on the relationship between tangent delta and frequency are essentially different.

关键词： rheological behavior waterborne dispersion bisphenol A epoxy resin

Synthesis and Electrical Conductivity of MDA[Ni(dmit)_2]_2

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Chinese Chemical Letters 1997年第10期8卷 917-918页

作者： Shu Qing SUN Xiao Yin XU Qi Chun ZHANG Pei Ji WU Dao Ben ZHU(Institule of Chemistry. Chinese Academy of sciences. beijing 100080)(basic School of {3. sciences. capital university of medical sciences. beijing 100054) Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China basic School of medical sciences Cap. University of Medical Sciences Beijing 100054 China

Single crystals of MDA[Ni(dmit)2]2 were synthesized by using electrooxidation *** conductivity measurements exhibit a semiconducting feature with high conductivity at roomtemperature

关键词： MDA dmit Wang Synthesis and Electrical Conductivity of MDA[Ni

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life Science,capital Normal university,{3. 10003.,china 2 college of Applied sciences and Humanities,{3. Union university,{3. 100083.china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. Department of Pharmacology,School of Chemical Biology & Pharmaceutical sciences,capital university of {3. sciences,beijing 100069,china 3.Institute of Cardiovascular Science at Health Science Center,Peking university beijing 100083.china 4 Institute of Molecular medicine and college of Life Science,Peking university,beijing 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular Science at Health Science Center Peking University Beijing 100083 China Institute of Molecular medicine and college of Life Science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3. inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

Mechanism for chronic pain generation

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Chinese Science Bulletin 2000年第9期45卷 775-783页

作者： XIE YikuanInstitute of basic medical sciences, Peking Union medical college, Chinese Academy of medical sciences, beijing 100005. Institute of basic medical sciences Peking Union Medical College Chinese Academy of Medical Sciences Beijing China

Neuropathic pain and the other abnormalities of sensation induced by axon injury or by peripheral nerve inflammation should result from functional compensations of the injured neurons during their regeneration. Ectopic distribution of proteins related to Na+, K+ and Ca2+ channels as well as of receptors on both membranes of injured axon and its cell body becomes a main pacemaker from which spontaneous ectopic afferent of primary sensatory neurons and crosstalk between neurons occur. Abnormal ectopic afferent activities lead to disorders of the sensation, such as hyperalgesia, allodynia, spontaneous pain and paraesthesia. Administration of some ion channel agents and/or α2-adrenergic blockers has shown efficiency in preventing neuropathic pain development and in relieving neuropathic pain.

关键词： chronic pain nerve injury ectopic firing ion channels sympathetic activity.

Spinal processing of bee venom-induced pain and hyperalgesia

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生理学报 2008年第5期60卷 645-652页

作者： Jun CHEN Institute for Biomedical sciences of Pain and Institute for Functional Brain Disorders,Tangdu Hospital,the Fourth Military medical {3.,Xi’an 71003.,china Institute for Biomedical sciences of Pain,capital medical {3.,beijing 100069,china Institute for Biomedical sciences of Pain and Institute for Functional Brain Disorders Tangdu Hospital the Fourth Military Medical University Xi'an 710038

Subcutaneous injection of bee venom causes long-term neural activation and hypersensitization in the dorsal horn of the spinal cord,which contributes to the development and maintenance of various pain-related *** unique behavioral 'phenotypes' of nociception and hypersensitivity identified in the rodent bee venom test are believed to reflect a complex pathological state of inflammatory pain and might be appropriate to the study of phenotype-based mechanisms of pain and *** this review,the spinal processing of the bee venom-induced different 'phenotypes' of pain and hyperalgesia will be *** accumulative electrophysiological,pharmacological,and behavioral data strongly suggest that different 'phenotypes' of pain and hyperalgesia are mediated by different spinal signaling *** the phenotype-based mechanisms of pain might be useful in development of novel therapeutic drugs against complex clinic pathological pain.

关键词：脊髓痛觉过敏蜂毒疼痛治疗方法

Milestone of the meridian science──970th anniversary of the Chinese Bronze Statue of Meridian

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Chinese Science Bulletin 1998年第5期43卷 353-362页

作者： ZHANG Renji college of Life sciences, Peking university, {3. 100871, china college of Life sciences Peking University Beijing 100871 China

For more than a thousand years, Chinese people were aware of the transmitted sensations by the application of needles on the body surface. This practice is called acupuncture. Acupuncture had been recorded and transcribed in writings and in drawings, until finally the acupoints were inscribed onto a bronze statue. The bronze statue was called the Meridian Figure. Deeply embodied in the bronze statue is a tripartite confrontation-prism representation of the humans body. This concept was a great scientific achievement in ancient china. The author traces the history of Meridian science described in traditional Chinese medical terms. Then he explores a clear analogy of the meridian pathway (MP) phenomenon. In a model system, by using a simple segmental in vertebrate, certain parallels can be demonstrated with the meridian concept. For example, the author demonstrated a clear correlation rule among the central mechano-sensory channels, and characteristics of positional discrimination in individual nerve cells from different receptive field inputs. The evidence suggests that the MP phenomenon is an objective neurobiological response. To clarify the research objective in this paper, the author suggests that the MP is a bi-directional pathway along which a positional message signal is transmitted. This phenomenon is evoked by physical stimulation, transmitted linearly across the human body segments, and is perceived by the brain. The MP consists of low resistance paths, is connected by the liquid media contained in the apposite membranous structure. At the cellular level, the regulation functions of MP must pass through along this low resistance path. Two aspects of the modern Meridian research are the functional regulation and the mechanism of intercellular liquid modulation at the nanometer level.

关键词： meridian pathway tripartite confrontation-prism coordinate position discriminative recognition apposite membranous structure.