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Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and *** (Primulaceae)

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Journal of Systematics and Evolution 2010年第2期48卷 109-117页

作者： 1,2Zhi-Kun WU 1Chang-Qin ZHANG 1(Kunming Institute of Botany,chinese academy of sciences,Kunming 650204,china) 2(graduate school of chinese academy of sciences,beijing 100049,china) (Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of chinese academy of sciences Beijing 100049 China)

The comparative pollination biology of a population of Primula beesiana,a population of ***,and an overlapping population of these two species in Yulong Shan,Yunnan Province,china,was studied in 2004 and *** results indicate that both *** and *** are typical heterostylous and obligate outcrossing species;the main pollinators of the two species were bees and *** the sites of all three populations,the main pollinating visitors of the two species showed preference for one of the two species,resulting in the ethological isolation of the two species by the *** ethological isolation contributes to the reproductive isolation of the two species,which supports the hypothesis that *** and *** are two distinct *** reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the *** addition,gene exchanges between *** and *** has occurred to some extent in the overlapping population,but whether natural hybridization has contributed to species diversification in Primula remains to be determined.

关键词： pollination biology Primula beesiana Primula bulleyana reproductive isolation

Molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and Evolution 2011年第2期49卷 138-145页

作者： 1,2 Xu QUAN 1 Shi-Liang ZHOU 1 (State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of sciences, beijing 100093, china) 2 (graduate school of the chinese academy of sciences, beijing 100049, china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate school of the chinese academy of sciences Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 38 populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

Cytotoxicity of carbon nanotubes

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Science china Chemistry 2008年第11期51卷 1021-1029页

作者： ZHU Ying1,2 & LI WenXin1 1 Laboratory of Nano-biology and Medicine, Shanghai Institute of Applied Physics, chinese academy of sciences, Shanghai 201800, china 2 graduate school of chinese academy of sciences, beijing 100049, china Laboratory of Nano-biology and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai China graduate school of chinese academy of sciences Beijing China

With large-scale production and application at large scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted great attention from scientists and governments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting CNTs cytotoxicity, including species of CNTs, impurities contained, lengths of CNTs, aspect ratios, chemical modification, and assaying methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we suggest that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be strengthened; assaying methods and evaluating criteria characterized by nanotoxicology should be gradually established.

关键词： carbon nanotubes (CNTs) cell bio-security

Suprathermal particle events observed by WIND spacecraft in interplanetary space during 1995―1999 and their classification

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Science china(Technological sciences) 2008年第9期51卷 1542-1553页

作者： SUN LingPeng1,2, WU DeJin1 & WANG DeYu1 1 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 2 graduate school of chinese academy of sciences, beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China graduate school of chinese academy of sciences Beijing China

Fifty-five suprathermal particle events were selected from WIND observations between 1995 and 1999. Based on systematic analysis on the observational characteristics of these events a two-parameter (the rising time and the flux ratio of electrons to protons in each event) classification method was proposed to classify these events. The three clas-sified classes are (1) impulsive electron events with the flux ratio of electrons to protons being bigger than 1 and rising time being shorter than 200 min, (2) impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 200 min, and (3) gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 200 min. In the past, "impulsive solar electron events" were under in-tense research. However, because the selection standards of their velocity dispersions or pitch-angle distributions were inadequate, statistical surveys of selected events were dif-ferent from each other and even some conclusions were not consistent with the theory, for example, the relation of type-III solar radio bursts to the "impulsive solar electron events". The first class of impulsive electron events are associated with type-III radio bursts and with clear velocity dispersions; therefore they ought to originate from the Sun. The second class of the events, which have short continuance time and usually are not associated with type-III radio bursts and without velocity dispersion, are still far away from inter-planetary shocks and most of them do not one-to-one correspond to corrotating interact-ing regions (CIRs); such events are possible results of local interplanetary magnetic field reconnection or electromagnetic disturbances. Finally, about 2/3 gradual proton events of the third class occur with interplanetary shocks, the delay times of which are almost equal to the rising time. Some of these events can be understood as particle accelerations by shocks.

关键词： suprathermal particles solar wind plasma solar eruptive activity interplanetary active regions

Novel Tumor-associated Antigen of Hepatocellular Carcinoma Defined by Monoclonal Antibody E4-65

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 359-365页

作者： Ke ZOU~(1,2), Jihang JU~(1,2), and Hong XIE~~(1*)1 Institute of Biochemist13, and Cell Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences, Shanghai 200031, china. 2 graduate school of the chinese academy of sciences beijing 100049, china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China graduate school of the chinese academy of sciencesbeijing 100049 China

A monoclonal antibody, E4-65, produced by immunizing mice with SMMC-7721 cells, a human hepatocellular carcinoma (HCC) cell line, was used to identify and characterize an unreported HCC-associated antigen. Indirect immunofluorescence studies showed that E4-65 antibody reacted with five out of eight HCC cell lines, but not with 10 non-HCC tumor cell lines or a normal liver cell line. Using immunohistochemical examination, E4-65 antigen was detected on the cell membranes and in the cytoplasm of human liver tumor tissues, but was not found in most other tumors, or normal adult or fetal tissues, except for a weakly positive reaction in tissues of the digestive system. Western blot analysis showed that E4-65 antibody bound to a 45 kDa protein in the human HCC cell line and tissue lysates. Enzyme treatment and lectin blotting did not detect the carbohydrate chain in E4-65 antigen. This HCC-associated protein represents a potentially useful target for diagnoses and immunotherapy of human HCC.

关键词： hepatocellular carcinoma immunohistochemistry monoclonal antibody neoplasm antigen

Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13°N

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Science china Earth sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2,YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2 & WANG XiaoMei1,2 1 Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment,Institute of Oceanology,chinese academy of sciences,Qingdao 266071,china 2 graduate school of chinese academy of sciences,beijing 100049,china Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate school of chinese academy of sciences Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12°42.30'N,103°54.48'W,water depth 2655 m) on the East Pacific Rise near 13°N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.30×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-1344×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-28.0×10-9),and Ta (0.203×10-9-1.21×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2 > 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2 > 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,Mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 34S value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13oN

Pretreatment with insulin enhances anticancer functions of 5-fluorou racil in human esophageal and colonic cancer cells

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Acta Pharmacologica Sinica 2007年第5期28卷 721-730页

作者： Ke ZOU~(1,2),Ji-hang JU~(1,2),Hong XIE~(1,3)~1 Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai 200031,china ~2 graduate school of the chinese academy of sciences,beijing,100049,china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of the chinese academy of sciences Beijing China

Aim:To investigate the effects of insulin on enhancing 5-fluorouracil (5-FU) anti-cancer functions and its mechanisms in the human esophageal cancer cell line(Eca 109) and human colonic cancer cell line (Ls-174-t).Methods:The effect ofinsulin/5-FU combination treatment on the growth of Eca 109 and Ls-174-t cellswas evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT) *** insulin treatment or insulin/5-FU treatment,cell cycle distri-bution of both cell lines was analyzed by flow *** blot assay wasused to assess the expression of caspase-3 and thymidylate synthase (TS).Apoptosis was detected by flow cytometry,DNA fragmentation assay,and termi-nal transferase dUTP nick end labeling assay (TUNEL).Moreover,the changes of5-FU uptake after insulin pretreatment were detected by HPLC assay and Westernblot ***:We found that insulin enhanced the inhibitory effect of 5-FU on cell proliferation when Eca 109 cells and Ls-174-t cells were pretreated withinsulin for the appropriate *** increased the cell number of the S phaseand the uptake of ***/5-FU treatment enhanced apoptosis of tumor cellsand upregulated the expression of cleaved caspase-3 compared with 5-FU ***,insulin/5-FU treatment induced the changes of free TS and the TSternary complex level compared with 5-FU treatment in Eca 109 and Ls-174-t ***:These data suggest that insulin enhances anticancer functions of 5-FU when it is treated before 5-FU for the appropriate time in human esophagealand colonic cancer cell lines.

关键词： apoptosis cell cycle 5-fluorouracil insulin

Ashkin-Teller Formalism for Elastic Response of DNA Molecule to External Force and Torque

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Communications in Theoretical Physics 2008年第2期49卷 525-528页

作者： CHANG Zhe~1 WANG Ping~(1,2) ZHENG Ying-Hong~(1,2) 1 Institute of High Energy Physics,the chinese academy of sciences,P.O.Box 918(4),beijing 100049,china 2 graduate school,the chinese academy of sciences,beijing 100049,china Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918(4) Beijing 100049 China graduate school the Chinese Academy of Sciences Beijing 100049 China

We propose an Ashkin Teller-like model for elastic response of DNA molecule to external force and *** base-stacking interaction is described in a simple and uniform *** obtain the phase diagram of dsDNA,andin particular,the transition from B form to the S state induced by stretching and *** elastic response of thessDNA is presented also in a unified *** close relation of dsDNA molecule structure with elastic response isshown *** calculated folding angle of the dsDNA molecule is 59.2°.

关键词： dsDNA elastic property

Morphological characteristics of leaf epidermis and size variation of leaf,flower and fruit in different ploidy levels in Buddleja macrostachya (Buddlejaceae)

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Journal of Systematics and Evolution 2009年第3期47卷 231-236页

作者： 1,2Gao CHEN 1Wei-Bang SUN 3Hang SUN 1(Kunming Botanical Garden, Kunming Institute of Botany, chinese academy of sciences, Kunming 650204, china) 2(graduate school of chinese academy of sciences, beijing 100049, china) 3(Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, chinese academy of sciences, Kunming 650204, china) (Kunming Botanical Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (graduate school of chinese academy of sciences Beijing 100049 China) (Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Buddleja macrostachya (Buddlejaceae) is a widespread shrub native to the Sino-Himalayan mountains and beyond. It has been found to occur at two ploidy levels, hexaploid, 2n=6x=114 and dodecaploid, 2n=12x=228. To determine if morphological characters might be used as indicators of ploidy levels, we measured floral and fruit length, relative and absolute leaf size, trichome density on both leaf surfaces, and stomatal density and length in different populations of B. macrostachya. In general, flower and fruit length, absolute leaf size, and stomatal length increased with an increase at ploidy level (P0.05) in different populations. Other characters studied such as trichome type, cuticular membrane and ornamentation of stomata, cell and stomatal shape, and anticlinal wall pattern were quite constant in this species. Thus it appears that flower and fruit length, absolute leaf size, and stomatal frequency and length can be used to distinguish hexaploid from dodecaploid cytotypes either in the fleld or in herbarium specimens.

关键词： Buddleja macrostachya dodecaploid hexaploid leaf epidermis ploidy level stomata.