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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 {3. sciences, beijing 100069, China Department of Anatomy, capital university of {3. sciences, beijing 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.

Overview of HBV whole genome data in public repositories and the Chinese HBV reference sequences

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progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a Graduate School of Chinese Academy of sciences, beijing 100049, China b beijing {3. of Genomics, Chinese Academy of sciences, beijing 1013.0, China c beijing Youan Hospital, capital medical university, beijing 100069, China Graduate School of Chinese Academy of sciences Beijing 100049 China beijing institute of Genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 229 HBV genomes in Chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in China. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the Chinese HBV database with the clinical information should be constructed.

关键词： public databases HBV genomic sequences Genotype Subtype Chinese reference sequences

Information extraction and CT reconstruction of liver images based on diffraction enhanced imaging

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progress in Natural Science:Materials International 2009年第8期19卷 955-962页

作者： Chunhong Hua,b, Tao Zhao a, Lu Zhanga, Hui Lia, Xinyan Zhao c, Shuqian Luoa, a College of biomedical Engineering, capital medical university, beijing 100069, China b National Laboratory of pattern Recognition, {3. of Automation, Chinese Academy of sciences, beijing 100080, China c Liver Research Center, beijing Friendship Hospital, capital medical university, beijing 100050, China [a]College of biomedical Engineering Capital Medical University Beijing 100069 China [b]National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China [c]Liver Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China

X-ray phase-contrast imaging (pCI) is a new emerging imaging technique that generates a high spatial resolution and high contrast of biological soft tissues compared to conventional radiography. Herein a biomedical application of diffraction enhanced imaging (DEI) is presented. As one of the pCI methods, DEI derives contrast from many different kinds of sample information, such as the sample’s X-ray absorption, refraction gradient and ultra-small-angle X-ray scattering (USAXS) properties, and the sample information is expressed by three parametric images. Combinedwith computed tomography (CT), DEI-CT can produce 3. volumetric images of the sample and can be used for investigating micro-structures of biomedical samples. Our DEI experiments for liver samples were implemented at the topography station of beijing Synchrotron Radiation Facility (BSRF). The results show that by using our provided information extraction method and DEI-CT reconstruction approach, the obtained parametric images clearly display the inner structures of liver tissues and the morphology of blood vessels. Furthermore, the reconstructed 3. view of the liver blood vessels exhibits the micro blood vessels whose minimum diameter is on the order of about tens of microns, much better than its conventional CT reconstruction at a millimeter resolution. In conclusion, both the information extraction method and DEI-CT have the potential for use in biomedical micro-structures analysis.

关键词： Diffraction enhanced imaging Computed tomography Information extraction X-ray Liver

Effects of the CNTF-collagen gel-controlled delivery system on rat neural stem/progenitor cells behavior

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Science China(Life sciences) 2010年第4期53卷 504-510页

作者： YANG ZhaoYang1, QIAO Hui2 & LI XiaoGuang1,3.1School of Biological Science and medical Engineering, Beihang university, beijing 100191, China 2public Heath School, Ningxia medical university, Yinchuan 750004, China 3.2} institute for Neuroscience, capital medical university, beijing 100069, China 1. School of Biological Science and medical Engineering Beihang University Beijing 100191 China2. Public Heath School Ningxia Medical University Yinchuan 750004 China3. Beijing Institute for Neuroscience Capital Medical University Beijing 100069 China

The injury of central nervous system (CNS) usually causes the cavity formation. Although transplantation of neural stem/precursor cells (NSpCs) into the lesioned area of CNS has been shown to be implicated in the functional restoration, the therapeutic result is limited by the poor survival of NSpCs as well as their insufficient proliferation and differentiation abilities. Type-1 collagen is considered as a candidate scaffold or drug delivery system to overcome the aforementioned obstacle. This study observed the effects of the CNTF (ciliary neurotrophic factor)-collagen gel-controlled delivery system and daily addition of soluble-form CNTF on the NSpC survival, migration, proliferation and differentiation. The results showed that, within 12 h of the initial co-culture, CNTF was released in a burst pattern, then the CNTF-collagen gel-controlled delivery system stably released CNTF for up to 12 d. The cell viability test, together with immunohistochemistry, RT-pCR and Western blotting, showed that the CNTF-collagen gel-controlled delivery system supported the NSpCs seeded on the surface of collagen gel survival and facilitated their migration and proliferation. The daily addition of soluble-form CNTF to the medium had similar effects to the CNTF-collagen gel-controlled delivery system, but large quantities of soluble-form CNTF were consumed during the entire process. Taken together, the CNTF-collagen gel-controlled delivery system not only provides a physical scaffold for the transplanted NSpCs to adhere and migrate, but also facilitates the NSpC survival, growth and proliferation, simultaneously reducing the consumption of the expensive growth factors. This system may be used to enhance the microenvironment in the lesioned area of CNS.

关键词： spinal cord neural stem/progenitor cells control release type-1 collagen CNTF

Studies on repairing of hemisected thoracic spinal cord of adult rats by using a chitosan tube filled with alginate fibers

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progress in Natural Science:Materials International 2006年第10期16卷 1051-1055页

作者： LI Xiaoguang, YANG Zhaoyang and YANG Yi ( beijing Center for Neural Regeneration and Repairing, capital university of {3. sciences, beijing 100054, China Department of Bioengineering, beijing university of Aeronautics and Astronautics, beijing 100083. China National Center of biomedical Analysis, beijing 100850, China) [a]beijing Center for Neural Regeneration and Repairing Capital University of Medical Sciences Beijing China [b]Department of Bioengineering Beijing University of Aeronautics and Astronautics Beijing China [c]National Center of biomedical Analysis Beijing China

A chitosan tube filled with alginate fibers was implanted into the injured spinal cord of a rat for repairing the damaged tissue. Twelve months after the operation, the morphological observation demonstrated that this chitosan tube could induce regeneration of myelinated and non-myelinated axons and blood vessels. The Basso-Beattie-Bresnahan (BBB) behavioral evaluation confirmed that the implants played a key role in the long-term restoration of rats motor functions. It is a promising start in the treatment of the patients with the injury of the spinal cord.

关键词： spinal cord injury regeneration function recovery chitosan alginate behavioral evaluation.

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

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

Effects of chitosan/collagen substrates on the behavior of rat neural stem cells

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Science China(Life sciences) 2010年第2期53卷 215-222页

作者： YANG ZhaoYang1,MO LinHong2,DUAN HongMei2 & Li XiaoGuang1,2 1 School of Biological Science and medical Engineering,Beihang university,beijing 100191,China 2 beijing institute for Neuroscience,capital medical university,beijing 100069,China 1. School of Biological Science and medical Engineering Beihang University Beijing 100191 China2. Beijing Institute for Neuroscience Capital Medical University Beijing 100069 China

Spinal cord and brain injuries usually lead to cavity *** transplantation by combining stem cells and tissue engineering scaffolds has the potential to fill the cavities and replace the lost neural *** chitosan and collagen have their unique *** this study,the effects of chitosan and collagen on the behavior of rat neural stem cells (at the neurosphere level) were tested in vitro in terms of cytotoxicity and supporting ability for stem cell survival,proliferation and *** the serum-free condition,both chitosan membranes and collagen gels had low cytotoxicity to *** is,cells migrated from neurospheres,and processes extended out from these neurospheres and the differentiated *** with the above two materials,chitosan-collagen membranes were more suitable for the co-culture with rat neural stem cells,because,except for low cytotoxicity and supporting ability for the cell survival,in this group,a large number of cells were observed to migrate out from neurospheres,and the differentiating percentage from neurospheres into neurons was significantly *** modification of chitosan-collagen membranes may shed light on in vivo nerve regeneration by transplanting neural stem cells.

关键词： chitosan collagen neural stem cells biocompatibility differentiation

Overexpression of heme oxygenasel protects smooth muscle cells against oxidative injury and inhibits cell proliferation

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Cell Research 2002年第2期12卷 123-132页

作者： MIN ZHANG, BAO HuI ZHANG, LI CHEN, WEI AN1 institute of Sports Medicine, The Third Hospital, peking university, beijing 100083. China 2Department of Cell Biology, {3. university of medical sciences, beijing 100054, China 1institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 1institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 2Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 2Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China

To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with Znpp-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of H

关键词： Heme oxygenase retroviral vector free radical cell proliferation vascular smooth muscle cells.