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

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

作者： ZHANG Renji college of life sciences, peking university, beijing 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.

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Biotic communities of the marine ecosystem in Meizhou Bay

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Journal of Environmental sciences 1996年第1期8卷 48-56页

作者： Ren Jiuchang Cai Xiaoming (Center of Environmental sciences,peking university, beijing 100871,china)Chen Bin(college of life sciences, peking university, beijing 100871, china )Li Peng(college of Chemistry and Molecular Engineering, peking university, Bei Ctr of Envmtl Sci Peking Univ Beijing China China

The current situation of biotic communities in Meizhou Bay is presented in this *** species composition,seasonal variation,and distribution of phytoplankton,zooplankton, red tide organisms,fishes,and benthos in Meizhou Bay were investigated,and the content of chlorophyll a and primary production and their seasonal variation were also *** water quality of Meizhou Bay was monitored by measuring the density of Escherichia coli. Results reveal that there is a great variety of species in Meizhou Bay and the water in Meizhou Bay is *** the individual numbers of various organisms are very low, especially those of ***,there are more than 40 species of red tide organisms and there exist opportunities of red tides between May and *** these demand cautious be taken in the future development of this area although it has great environment capacity.

关键词： biotic community marine ecosystem Meizhou Bay.

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Nuclear apoptosis induced by isolated mitochondria

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Cell Research 2000年第3期10卷 221-232页

作者： JIANG ZHENG FAN, YUN ZHAO, XIA HONG, ZHONG HE ZHAI (college of life sciences, peking university, beijing, 100871 china) collegeoflifesciences PekingUniversityBeijingChina.

We isolated and purified mitochondria from mouse livers and spinach leaves. When added into egg extracts of Xenopus laevis, they caused nuclei of mouse liver to undergo apoptotic changes. Chromatin condensation, margination and DNA ladder were observed. After incubating isolated mitochondria in some hypotonic solutions, and centrifuging these mixtures at high speed, we got mitochondrial supernatants. It was found that in the absence of cytosolic factor, the supernatant alone was able to induce apoptotic changes in nuclei. The effective components were partly of protein. DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC- YVADCHO. Meanwhile, caspase inhibitors fully blocked chromatin condensation. Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted. It was found that this endonuclease is different from endonuclease G, cytochrome c-induced nuclease, or Ca2+-activated endonuclease.

关键词： Mitochondria supernatant apoptosis egg ex- tract nuclei DNA cleavage.

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Structural Analysis and Identification of Cis-Elements of Rice osRACD Gene

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 191-198页

作者： Yun-Zhe XU, Rui-Lin YOU and Nai-Hu WU Institute of Genetics and Developmental Biology, Chinese Academy of sciences, beijing 100080, china 2college of life sciences, peking university, beijing 100871, china Institute of Genetics and Developmental Biology Chinese Academy of Sciences college of life sciences Peking University

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 58S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5' upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (–799 to –686 nt, and –686 to –431 nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 58S rice under short day (58S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 58S rice under long day (58S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.

关键词： photoperiod-sensitive male genic sterile rice osRACD gene photoperiod fertility transformation cis-element

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Induction of apoptosis in purified animal and plant nuclei by Xenopus egg extracts

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Cell Research 1999年第2期9卷 79-90页

作者： JIANG ZHENG FAN SHAN ZHU YING LI SUN ZHONG HE ZHAI (college of life sciences, peking university, beijing 100871, china) 1college of life sciences Peking University Beijing 100871 China 1college of life sciences Peking University Beijing 100871 China 1college of life sciences Peking University Beijing 100871 China 1college of life sciences Peking University Beijing 100871 China

We have developed a cell-free system that can trigger the nuclei purified from mouse liver and suspensioncultured carrot cells to undergo apoptosis as defined by the formation of apoptotic bodies and nucleosomal DNA fragments. The effects of different divalent cations and cycloheximide on DNA cleavage in this system were *** fact that nuclei of plant cells can be induced to undergo apoptosis in a cell-free animal system suggests that animals and plants share a common signal transduction pathway triggering in the initiation stage of apoptosis.

关键词： Apoptosis Xenopus laevis cell-free carrot mouse dATP

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GM-CSF-induced Ca_(2+) -activated non-voltage-dependent inwardly rectifying K_+ channel in murine peritoneal exudate macrophages

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Chinese Science Bulletin 1997年第11期42卷 947-952页

作者： ZHANG Xiaofeng, FENG Meifu, WU Caihong and ZHOU Pei’aiState Key Laboratory of Biomembrane and Membrane Biotechnology, Chinese Academy of sciences, beijing 100080, china 1 . In-stitute of Zoology, Chinese Academy of sciences, beijing 100080, china 2 college of life sciences, peking university, beijing 100871, china State Key Laboratory of Biomembrane and Membrane Biotechnology Chinese Academy of Sciences Beijing 100080 China

GRANULOCYTE-MACROPHAGE colony-stimulating factor(GM-CSF),a member in the family ofglycoprotein cytokines,can not only act to stimulate proliferation of immature progenitors,butalso enhance differentiated functions of mature effector *** has two kinds of biologicaleffects on mature effector cells,*** effect and indirect *** latter is also

关键词： K+ channel patch clamp GM-CSF macrophage.

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Callus formation in relation to changes of the membrane Ca^(2+) in the graft unions of Ginkgo biloba L.

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Chinese Science Bulletin 1998年第20期43卷 1732-1736页

作者： YANG Xiong and LI Zhengli (Lee C. L.) college of life sciences, peking university, beijing 100871, china college of life sciences Peking University Beijing China

The relationship between the callus formation and intracellular Ca 2+ at the early stage of development of graft unions in Ginkgo biloba L. was investigated. On the second day after grafting, part of the undamaged living cells at the graft interface of the stock and scion in the regions of the cortex and pith began to dedifferentiate or divide. 8 d after grafting, a great number of callus cells were produced from the cortex and phloem, while callus bridges linking the stock with scion formed between the callus cells of the graft partners from the cortex. A membrane Ca 2+ probe, chlortetracycline (CTC), was used to locate the intracellular Ca 2+ distribution and it was found that the cortical and pith parenchyma cells were the first to show remarkably increased CTC Ca 2+ fluorescence, suggesting that the cortical and other parenchyma cells play a leading role at the early stage of development of graft unions by earlier dedifferentiation and more rapid production of callus cells.

关键词： callus formation membrane Ca 2+ graft union Ginkgo biloba.

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LDFF,the large molecular weight DNA fragmentation factor,is responsible for the large molecular weight DNA degradation during apoptosis in Xenopus egg extracts

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Cell Research 2004年第2期14卷 134-140页

作者： Zhi Gang LU, Chuan Mao ZHANG~*, Zhong He ZHAI~* Department of Cell Biology and Genetics, college of life sciences, peking university, beijing 100871, china. Department of Cell Biology and Genetics College of Life Sciences Peking University Beijing 100871 China.

DNA degradation is a biochemical hallmark in apoptosis. It has been demonstrated in many cell types that there are two stages of DNA fragmentation during the apoptotic execution. In the early stage, chromatin DNA is cut into large molecular weight DNA fragments, although the responsible nuclease(s) has not been recognized. In the late stage, the chromatin DNA is cleaved further into short oligonucleosomal fragments by a well-characterized nuclease in apoptosis, the caspase-activated DNase (CAD/DFF40). In this study, we demonstrate that large molecular weight DNA fragmentation also occurs in Xenopus egg extracts in apoptosis. We show that the large molecular weight DNA fragmentation factor (LDFF) is not the Xenopus CAD homolog XCAD. LDFF is activated by caspase-3. The large molecular weight DNA fragmentation activity of LDFF is Mg2+-dependent and Ca2+-independent, can occur in both acidic and neutral pH conditions and can tolerate 45℃ treatment. These results indicate that LDFF in Xenopus egg extr

关键词： apoptosis caspase-activated DNase (CAD) large molecular weight DNA fragmentation factor (LDFF).

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Research progress in gecko locomotion and biomimetic gecko-robots

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Progress in Natural Science:Materials International 2007年第1期17卷 1-5页

作者： DAI Zhendong and SUN Jiurong ( Institute of Bio-inspired Structure and Surface Engineering, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china college of life sciences, peking university, beijing 100871, china) Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China college of life sciences Peking University Beijing 100871 China

Geckos are known for their excellent ability to climb walls and run on ceilings. Previous studies of the gecko's locomotive and adhesive mechanisms, its neuro-sensory and neuro-modulatory systems, its fabrication of artificial setae array, and other related developments, have inspired further research on gecko-based and gecko-like robots. Key research findings in this area are reviewed in the present paper.

关键词： gecko locomotion biomimetic modulation gecko-like robot.

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Recombinant scorpion insectotoxin AaIT kills specifically insect cells but not human cellss

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Cell Research 2002年第2期12卷 143-150页

作者： SHENG JIAN JI, FENG LIU, ER Qiu LI, Yu XIAN ZHUThe National Laboratory of Protein Engineering and Plant Genetic Engineering, college of life sciences, peking university, beijing 100871, china 1The National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China 1The National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China 1The National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China 1The National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth （Plutella xylostella） larvae were killed in both groups with LC50 value of 18.4 μM and 0.70 μM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 μM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3 μM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma

关键词： Scorpion toxin AaIT prokaryotic expression cytotoxicity.

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