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Cytological Events during Zygote Formation of the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2010年第3期52卷 254-264页

作者： jian-guo cao quan-xi wang nai-ying yang Wen-Mei Bao College of Life and Environment Science Shanghai Normal University Shanghai 200234 China

The cytological events, including nuclear fusion, digestion of male organelles and rebuilding of the plasmalemma and cell wall, during zygote formation of the fern Ceratopteris thalictroides （L.） Brongn. are described based on the observations of transmission electron microscopy. When the spermatozoid enters the egg and contacts the cytoplasm, the male chromatin relaxes continually. The microtubular ribbon （MTr） is separated from the male nucleus and then an envelope reappears around the male nucleus. During nuclear fusion, the egg nucleus becomes highly irregular and extends some nuclear protrusions. It is proposed that the protrusions fuse with the male nucleus actively. After nuclear fusion the irregular zygotic nucleus contracts gradually. It becomes spherical before the zygote divides. The male chromatin is identifiable as fibrous structure in the zygotic nucleus in the beginning, but it gradually becomes diffused completely. The male organelles, including the MTr, multilayered structure, flagella and the male mitochondria are finally digested in the zygotic cytoplasm. Finally a new plasmalemma and cell wall are formed outside the protoplast. The organelles in the zygote are rearranged, which produces a horizontal polarity zygote. The zygote divides with an oblique-vertical cell plate facing the apical notch of the gametophyte.

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Positive effect of Mo on mechanical properties of a Ni-42W-10Co-x Mo medium heavy alloy

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China Foundry 2025年

作者： guo-xin cao jian-xin Dong Yong-sheng He He jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology Beijing xi'an Superalloy Technology Co. Ltd. School of Materials Science and Engineering Beijing Institute of Technology Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou University

In this study,a novel Ni-W-Co-Mo medium heavy alloy (MHA) was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-xM o alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypoeutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-xM o alloys is Mo-induced solid solution strengthening and precipitation strengthening.

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Formation of the Fertilization Pore during Oogenesis of the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2010年第6期52卷 518-527页

作者： jian-guo cao quan-xi wang Wen-Mei Bao College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China

The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum （ER）, but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns.

关键词： Oogenesis Ferns Cells Eggs Lymphocytes

Casticin-induced apoptosis involves death receptor 5 upregulation in hepatocellular carcinoma cells

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World Journal of Gastroenterology 2011年第38期17卷 4298-4307页

作者： Jun yang Yun yang Li Tian xi-Feng Sheng Fei Liu jian-guo cao Department of Pathology The Third Xiangya Hospital of Central South University Changsha 410013 HunanProvince China Laboratory of Medical Engineering Medical College HunanNormal University Changsha 410013 Hunan Province China

AIM:To investigate the apoptotic activities of casticin in hepatocellular carcinoma(HCC) cells and its molecular ***:PLC/PRF/5 and Hep G2 cell lines were cultured in vitro and the inhibitory effect of casticin on the growth of cells was detected by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolim bromide(MTT) *** apoptotic cell death was examined using the cell apoptosis enzyme linked immunosorbent assay(ELISA) detection kit,flow cytometry(FCM) after propidium iodide(PI) staining and DNA agarose gel *** caspase activities were measured using *** oxygen species(ROS) production was evaluated by FCM after dichlorodihydrofluorescein diacetate(DCFH-DA) probe *** glutathione(GSH) content was measured using a glutathione assay *** expression of death receptor(DR)4 and DR5 proteins was analyzed by Western blotting and ***:Casticin significantly inhibited the growth of human HCC(PLC/PRF/5 and Hep G2) cells in a dosedependent manner(P xidants,acetylcysteine(NAC) and GSH restored GSH content and attenuated casticin-induced *** contrast,the nonthiol antioxidants,butylated hydroxyanisole and mannitol failed to do *** the HCC cells treated with casticin for 24 h,DR5 protein level was *** expression of DR5 protein induced by casticin was inhibited by *** wi

关键词： Hepatocellular carcinoma Casticin Glutathione Death receptor 5

Characterization and Wettability of ZnO Film Prepared by Chemical Etching Method

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Chemical Research in Chinese Universities 2013年第2期29卷 333-337页

作者： guo Hua-xi JIA Hui-ying ZENG jian-bo CONG Qian REN Lu-quan Key Laboratory of Bionic Engineering Ministry of Education Jilin University Changchun 130025 P. R. China

ZnO thin films were prepared by a chemical etching method and their wettability was investigated. The structure and surface composition structure were characterized by means of scanning electron microscopy, X-ray photoelectronic spectrometry（XPS）, X-ray diffraction（XRD） and Raman spectrometry. These analyses reveal that the etched films were large-scale micro-nanohierarchical structures composed of a Zn core and a ZnO coating. Superhy- drophobic surfaces with water contact angles of over 150~ were obtained by n-octadecanethiol（ODT） modification. The XPS and Raman results indicate that ODT molecules were bound to the ZnO surface with the S head group by forming Zn--S bond.

关键词： ZnO Chemical etching Micro-nanostructure Raman spectrometry Wettability

Review on recent advances of inorganic electrode materials for potassium-ion batteries

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Tungsten 2024年第1期6卷 174-195页

作者： jian-Zhen xiong Ze-Cheng yang xin-Liang guo xi-ying wang Chao Geng Zong-Fu Sun An-Yong xiao quan-Chao Zhuang Ya-xin Chen Zhi-Cheng Ju School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of *** electrode materials are the key factors to determine the electrochemical performance of devices,relevant research is being carried out to build high-performance *** recent years,significant progress has been made in the study of the design of inorganic electrode ***,we review the cathode materials(Prussian blue and its analogues,layered oxides and poly anionic compounds)and the anode materials(antimony-based,selenium-based and bismuth-based compounds).On the basis of previous work,the structural design principles for improving the performance of electrode materials are reasonably *** the same time,the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.

关键词： Inorganic electrode materials Potassium-ion batteries Cathode materials Anode materials

Dentin matrix protein 1 and phosphate homeostasis are critical for postnatal pulp, dentin and enamel formation

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International Journal of Oral Science 2012年第4期4卷 189-195页

作者： Afsaneh Rangiani Zheng-guo cao ying Liu Anika Voisey Rodgers Yong jiang Chun-Lin Qin jian-quan Feng Biomedical Sciences Baylor College of DentistryTexas A&M Health Science Center

Deletion or mutation of dentin matrix protein 1 （DMP1） leads to hypophosphatemic rickets and defects within the dentin. However, it is largely unknown if this pathological change is a direct role of DMP1 or an indirect role of phosphate （Pi） or both. It has also been previously shown that Klotho-deficient mice, which displayed a high Pi level due to a failure of Pi excretion, causes mild defects in the dentinal structure. This study was to address the distinct roles of DMP1 and Pi homeostasis in cell differentiation, apoptosis and mineralization of dentin and enamel. Our working hypothesis was that a stable Pi homeostasis is critical for postnatal tooth formation, and that DMP1 has an antiapoptotic role in both amelogenesis and dentinogenesis. To test this hypothesis, Dmpl-null （Dmpl-/-）, Klotho-deficient （kl/kl）, Dmpl/Klotho-double-deficient （Dmpl-/-/kl/kl） and wild-type （WT） mice were killed at the age of 6 weeks. Combinations of X-ray, microcomputed tomography （I^CT）, scanning electron microscopy （SEM）, histology, apoptosis and immunohistochemical methods were used for characterization of dentin, enamel and pulp structures in these mutant mice. Our results showed that Dmpl-/- （a low Pi level） or kl/kl（a high Pi level） mice displayed mild dentin defects such as thin dentin and a reduction of dentin tubules. Neither deficient mouse line exhibited any apparent changes in enamel or pulp structure. However, the double-deficient mice （a high Pi level） displayed severe defects in dentin and enamel structures, including loss of dentinal tubules and enamel prisms, as well as unexpected ectopic ossification within the pulp root canal. TUNEL assay showed a sharp increase in apoptotic cells in ameloblasts and odontoblasts. Based on the above findings, we conclude that DMP1 has a protective role for odontoblasts and ameloblasts in a pro-apoptotic environment （a high Pi level）.

关键词： apoptosis dentin dentin matrix protein 1 enamel Klotho phosphate

In-situ observation of microstructural evolution in reheated low carbon bainite weld metals with various Ni contents

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Journal of Iron and Steel Research International 2017年第12期24卷 1206-1214页

作者： Gao-jun Mao Rui cao jian-hong Chen xi-li guo Yong jiang Department of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050GansuChina State Key Laboratory of Advanced Processing and Recycling of Non ferrous Metals Lanzhou University of TechnologyLanzbou 730050GansuChina Atlantic China Welding Concumables Inc.Zigong 643000SichuanChina

Microstructural evolution in weld metals was in-situ observed through utilizing a laser scanning confocal microscope at two cooling *** specimens with various nickel contents were adopted for the *** the specimen with low fraction of Ni（≤2 wt.%）,granular bainite microstructure（*** surface relief）transformation from intragranular nucleation site was in-situ observed,while,lath bainite microstructure originating from grain boundary of austenite was in-situ observed for specimens with high mass percentage of Ni（≥4 wt.%）.With increasing nickel content,the transformation temperature *** prior austenite grain size was initially depressed and subsequently coarsened dramatically with the addition of *** microstructure difference was ascribed to various nucleation sites and growth direction in the *** account of those observations,not only the chemical component,cooling rate and microstructure were systematically correlated,but also the microstructural evolution was definite.

关键词： Weld metal Ni content Bainite Nucleation site Growth In-situ observation

Short term effects of small incision lenticule extraction surgery on corneal endothelium

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International Journal of Ophthalmology(English edition) 2016年第4期9卷 536-539页

作者： Dan-yang wang Man-Li Liu Yi-Le Chen xiao-ying Zhang yang-Tao Xu jian-Chao wang Chi-Ho To jian-guo wang quan Liu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina Department of Ophthalmology Liuzhou Worker's HospitalLiuzhou 545006Guangxi Zhuang Autonomous RegionChina Department of Ophthalmology the Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710000Shaanxi ProvinceChina Laboratory of Experimental Optometry Centre for Myopia ResearchSchool of Optometrythe Hong Kong PolytechnicUniversityHong KongChina Wuzhishan Ophthalmic Hospital Wuzhishan 572200Hainan ProvinceChina Hainan Eye Hospital Zhongshan Ophthamic CenterSun Yat-sen UniversityHaikou 570311Hainan ProvinceChina

AIM： To assess the effects of small incision lenticule extraction（SMILE） surgery on the corneal endothelium at1 d to 1mo postoperatively.·METHODS： A retrospective, observational study was conducted on 47 patients（47 eyes） who received SMILE surgery. Patients were grouped according to contact lens wear condition. The corneal endothelium was examined preoperatively and at 1d, 1wk and 1mo *** corneal endothelium was analyzed for endothelial cell density（ECD）, percentage of hexagonal cells, and coefficient of variation（CV） of cell size.·RESULTS： There were no significant decrease in the ECD, percentage of hexagonal cells or increase in CV at1 d, 1wk and 1mo postoperatively（P 〉0.05）. However,there was a small increase of ECD by 2.88% in contact lens wearers（78.26±113.62 cell/mm2, P 〈0.05）.· CONCLUSION： SMILE has no significant adverse effects on the corneal ECD and morphology during 1mo follow-up time.

关键词： myopia corneal endothelium refractive surgery