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Chinese science Bulletin 2000年第19期45卷 1729-1734页

作者： SUN DayeInstitute of molecular cell biology, Hebei Normal university, Shijiazhuang 050016, china Institute of molecular cell biology Hebei Normal University Shijiazhuang China

Generally, cell signal molecules are classified into the extracellular signal molecules (the first messengers) and the intracellular signal ones (the second messengers). Cyclic adenosine monophosphate (cAMP), calcium ions and calmodulin (CaM) are the traditional intracellular messengers, but they are also present in extracellular matrix (ECM). Some of them have been discovered to act as the first messengers through cell surface receptors. Other second messengers, such as cyclic guanosine monophosphate (cGMP), cyclic adenosine diphosphate ribose (cADPR) and annexin, are also found existing outside animal and plant cells. The existence of these messengers with intracellular-extracellular compatible functions in cells may be a regular biological phenomenon. These compatible messengers might be the communication factors between intracellular and extracellular regions or among the cell populations, and are also important in regulating cell development procedure.

关键词： intracellular signal extracellular signal compatible messenger.

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD

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Chinese Journal of Polymer science 2002年第4期20卷 353-360页

作者： Cai-yuan Pan Lei Tao Ye Liu Department of Polymer science and Engineering university of science and technology of china, hefei 2.002. china Department of Polymer science and Engineering University of Science and Technology of China Hefei 230026

A novel tetrafunctional initiator, C [CH_2O (CH_2)_3 OOCCH(Br)CH_3]_4 (1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4-armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4-armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of 'living' character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4-armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4-armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4-armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.

关键词： Tetrafunctional initiator Atom transfer radical polymerization 4-Armed polystyrene 4-Armed poly(styrene-b-pnitrophenyl methacrylate) Unimolecular micelles

Evolution of cd59 gene in mammals

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science china(Life sciences) 2007年第6期50卷 773-779页

作者： GONG YuanYing1,2, PENG MinSheng1,2, ZHOU WeiPing1,3,4 & ZHANG YaPing1,4 1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 molecular and cell biology, university of science and technology of china, hefei 2.002., china 4 Laboratory for Conservation and Utilization of Bio-resources, Yunnan university, Kunming 650091, china State Key Laboratory of Genetic Resources Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Graduate university of the Chinese Academy of sciences Beijing 100049 China molecular cell biology University of Science technology of china Hefei 230026 China Laboratory for Conservation Utilization of Bio-resources Yunnan University Kunming 650091 China

The CD59-coding sequences were obtained from 5 mammals by PCR and BLAST, and combined with the available sequences in GenBank, the nucleotide substitution rates of mammalian cd59 were calcu- lated. Results of synonymous and nonsynonymous substitution rates revealed that cd59 experienced negative selection in mammals overall. Four sites experiencing positive selection were found by using "site-specific" model in PAML software. These sites were distributed on the molecular surface, of which 2 sites located in the key functional domain. Furthermore, "branch-site-specific" model detected 1 positive site in cd59a and cd59b lineages which underwent accelerated evolution caused by positive selection after gene duplication in mouse.

关键词： cd59, evolution, positive selection

CONTROLLED RADICAL COPOLYMERIZATION OF STYRENE AND MALEIC ANHYDRIDE UNDER GAMMA RADIATION IN THE PRESENCE OF BENZYL DITHIOBENZOATE

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Chinese Journal of Polymer science 2002年第6期20卷 525-530页

作者： De-cheng Wu Ying-fang Zou Cai-yuan Pan Department of Polymer science and Engineering university of science and technology of china, hefei 2.002., china Univ Sci & Technol china Dept Polymer Sci & Engn Hefei 230026 Peoples R China

The copolymerization of styrene (St) with maleic anhydride (MAh) under gamma radiation at room temperature in the presence of benzyl dithiobenzoate (BDTB) was found to display 'living' nature evidenced by constant concentration of chain radicals during the copolymerization, linear evolution of molecular weights with conversion and narrow molecular weight distribution (M-w/M-n = 1.23-1.35). The compositional analysis and the sequence structural information of the copolymers obtained from DEPT (Distortionless Enhancement by Polarization Transfer) experiments demonstrate that the copolymers obtained also possess strictly alternating structure.

关键词： controlled radical polymerization alternating copolymer maleic anhydride styrene

An increase in opening of BKCa channels in smooth muscle cells in streptozotocin-induced diabetic mice

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Acta Pharmacologica Sinica 2004年第6期25卷 42-48页

作者： Chun-ling YE2, Bing SHEN4, Xian-da REN, Rong-jing LUO3, Sheng-yuan DING3, Fu-man YAN3, Jia-hua JIANG Department of Pharmacology, Pharmacy College of Ji-nan university, Guangzhou 510632 3Department of Physiology, Guangzhou university of Traditional Chinese Medicine, Guangzhou 510407 4Department of molecular biology and cell biology, School ofLife sciences, university of sciences and technology of china, hefei 230036, china Department of Pharmacology Pharmacy College of Ji-nan University Guangzhou 510632 Chin

AIM: To investigate the changes of function of large conductance of calcium-activated potassium channels (BKCa channels) in thoracic aortic smooth muscle cells in early stage of streptozotocin (STZ)-induced diabetic C57BL/6J mice. METHODS: Vascular muscle tension in the isolated thoracic aortic rings of mice was compared, and the role of BKCa channels in relaxation of isolated mice thoracic aortic rings induced by acetylcholine (ACh) was determined. Meanwhile, single vascular smooth muscle cells (VSMCs) were isolated by collagenase, and BKCa currents were recorded by patch-clamp single channel recording technique in symmetric high potassium solution. RESULTS: Tetraethylammonium (TEA) 1 mmol/L, a selective calcium-activated potassium channel blocker, caused significant rightward shift in the concentration-response curves of ACh in the isolated thoracic aortic rings of diabetic mice and pD2 value of ACh-induced relaxation was decreased notably after TEA treatment [(6.3±0.4) vs (6.9±0.5), n=10 rings from 7 mice, P0.05]. Furthermore, conductance of BKCa channels in single thoracic aortic smooth muscle cells was decreased [(199±15) pS, n=10 cells from 7 mice vs (266±11) pS, n=12 cells from 6 mice, Pcells from 6 mice, P32±98), n=6 cells from 6 mice, Pcells in the early stage of STZ-induced diabetic C57BL/6J mice by reducing mean closed time, but the conductance of BKCa channels was decreased.

关键词： diabetes mellitus streptozotocin aorta patch-clamp techniques potassium channels calcium

Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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science china(Technological sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & molecular Engineering,Qingdao university of science & technology,Qingdao,china 2 College of Information science & technology,Qingdao university of science & technology,Qingdao,china Institute of Chemistry & molecular Engineering Qingdao University of Science & Technology Qingdao China College of Information science & technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

Identification and Characterization of a Rat Novel Gene RSEP4 Expressed Specifically in Central Nervous System

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 501-507页

作者： Xi-Dao WANG1,2, Ling-Wei KONG1, Zhi-Qin XIE1, Yu-Qiu ZHANG3, Zhi-Xin LIN2, Zhi-Qi ZHAO3,Lei YU4, and Nai-He JING1* 1 Laboratory of molecular cell biology, Laboratory of Stem cell biology, Institute of Biochemistry and cell biology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Graduate School of the Chinese Academy of sciences, Shanghai 200031, china School of Life science and Biotechnology, 2 Shanghai Jiaotong university, Shanghai 200030, china Institute of Neurobiology, Fudan university, Shanghai 200433, china 3 4 Department of cell biology, Neurobiology and Anatomy, College of Medicine, university of Cincinnati, Cincinnati, Ohio, USA Laboratory of molecular cell biology and Stem cell biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Shanghai China

The low-abundantly expressed genes composed the majorities of the mRNAs expressed in the central nervous system (CNS), and were thought to be important for the normal brain functions. Through differential screening a low-abundance cDNA sublibrary with mRNA from neuropathic pain of chronic constriction injury (CCI) model, we have identified a novel rat gene, rat spinal-cord expression protein 4 gene (RSEP4). The total length of RSEP4 cDNA is 2006 bp, with a 501 nucleotide open reading frame (ORF) that encodes a 167 amino acid polypeptide. Northern blot revealed that RSEP4 was expressed specifically in the CNS. In situ hybridization showed that the mRNA of RSEP4 was strongly expressed in the CA1, CA2, CA3 and DG regions of hippocampus, the Purkinje cells of cerebellum, and the small sensory neurons of dorsal horn and large motor neurons of ventral horn of spinal cord. Over-expression of RSEP4-EGFP fusion protein in the human embryonic kidney 293T cells showed that RSEP4 protein was mainly localized in the cell cytoplasm. These results suggest that RSEP4 may play some roles in the CNS.

关键词： central nervous system (CNS) rat Northern blot in situ hybridization

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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science china(Technological sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & molecular Engineering, Qingdao university of science & technology, Qingdao 266000, china 2 College of Information science technology, Qingdao university of science & technology, Qingdao 266000, china Institute of Chemistry & molecular Engineering Qingdao University of Science & Technology Qingdao 266000 China College of Information science technology Qingdao University of Science & Technology Qingdao 266000 China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to china and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

Effects of Cu^(2+) on characteristic of SV currents

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science china Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1,2 & YANG Pin1 1. Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education, Institute of molecular science, Shanxi university, Taiyuan 030006, china 2. Institute of Environment science, Taiyuan university of science and technology, Taiyuan 030024, china 1. Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China 2. Institute of Environment science Taiyuan University of Science and Technology Taiyuan 030024 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2+ on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2+ in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2+ significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2+. These results show that there may be some Cu2+ binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2+, SV channel.

Metal-amyloid-β peptide interactions: a preliminary investigation of molecular mechanisms for Alzheimer’s disease

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science china Chemistry 2007年第4期50卷 453-467页

作者： JIAO Yong & YANG Pin Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education, Institute of molecular science, Shanxi university, Taiyuan 030006, china 1. Key Laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China

Although humans have spent exactly 100 years combating Alzheimer’s disease (AD), the molecular mechanisms of AD remain unclear. Owing to the rapid growth of the oldest age groups of the popula-tion and the continuous increase of the incidence of AD, it has become one of the crucial problems to modern sciences. It would be impossible to prevent or reverse AD at the root without elucidating its molecular mechanisms. From the point of view of metal-amyloid-β peptide (Aβ) interactions, we review the molecular mechanisms of AD, mainly including Cu2+ and Zn2+ inducing the aggregation of Aβ, cata-lysing the production of active oxygen species from Aβ, as well as interacting with the ion-channel-like structures of Aβ. Moreover, the development of therapeutic drugs on the basis of metal-Aβ interactions is also briefly introduced. With the increasingly rapid progress of the molecular mechanisms of AD, we are now entering a new dawn that promises the delivery of revolutionary developments for the control of dementias.

关键词： Alzheimer’s disease (AD) amyloid-β peptide Cu2+ Zn2+ molecular mechanisms aggregation active oxygen species ion channel