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Cell Research 1999年第1期9卷 51-59页

作者： ZHAO hua yong hua xu (Shanghai Institute of Cell Biology, Chinese Academy of Sciences, 320 yue-yang Road, Shanghai 200031, China) 1Shanghai Institute of Cell Biology Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China 1Shanghai Institute of Cell Biology Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China

Mad protein has been shown as an antagonist of cMyc protein in some cell lines. The effect of Mad protein to the malignant phenotype of human hepatoma BEL7404 cell line was investigated experimentally. An eukarryotic vector pCDNA Ⅲ containing full ORF fragmentof mad cDNA was transfected into targeted cells. Under G418 selection, stable Mad-overexpressed cells were *** on the effect of Mad over-expression in cell proliferation and cell cycle revealed that cell morphology of the Mad-overexpressed BEL-7404-M1 cells was significantly different from the parent and control vector transfected cells. DNA synthesis, cell proliferation and anchorage-independent growth in soft-agar of the madtransfected cel1s were partially inhibited in comparison to control *** Cytometry analysis indicated that mad over-expression might block more transfectant cells at G0/G1 phase, resulting in the retardation of cell proliferation. RT-PCR detected a marked inhibition of the expression of cdc25A, an important regulator gene of G0/G1to S phase in cell cycle. It was also found that Mad protein overexpression could greatly suppress p53-mediated apoptosis in BEL-7404-M1 cells in the absence of ***, Mad proteins may function as a negative regulator antagonizing c-Myc activity in the control of cell growth and apoptosis in human hepatocellular carcinoma BEL7404 *** and regulation of cell growth and apoptosis

关键词： Mad c-Myc cell growth apoptosis human hepatoma cells

Recent advances in Ga-based solar-blind photodetectors

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Chinese Physics B 2019年第2期28卷 49-57页

作者： Ming-sheng xu Lei Ge Ming-ming Han Jing huang hua-yong xu Zai-xing Yang School of Microelectronics Shandong University Shenzhen Research Institute of Shandong University School of Mechatronics Engineering Guizhou Minzu University

Solar-blind ultraviolet photodetectors have many advantages, such as low false alarm rates, the ability to detect weak signals, and high signal-to-noise ratios. Among the various functional solar-blind ultraviolet photodetectors, Ga-based alloys of AlGaN and Ga_2O_3 are the most commonly adopted channel semiconductor materials and have attracted extensive research attention in the past decades. This review presents an overview of the recent progress in Ga-based solar-blind photodetectors. In case of AlGaN-based solar-blind ultraviolet photodetectors, the response properties can be improved by optimizing the AlN nucleation layer and designing the avalanche structure. On the other hand, we also discuss the morphology and growth methods of Ga_2O_3 nanomaterials and their effect on the performance of the corresponding solarblind photodetectors. The mechanically exfoliated Ga_2O_3 flakes show good potential for ultraviolet detection. Also, Ga_2O_3 nanoflowers and nanowires reveal perfect response to ultraviolet light. Finally, the challenges and future development of Ga-based functional solar-blind ultraviolet photodetectors are summarized.

关键词： solar-blind photodetector AlGaN Ga2O3

THEORETICAL AND EXPERIMENTAL STUDIES OF HYDRAULIC CHARACTERISTICS OF DISCHARGE TUNNEL WITH VORTEX DROP

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Journal of Hydrodynamics 2010年第4期22卷 582-589页

作者： CHEN hua-yong xu Wei-lin DENG Jun NIU Zhi-pan LIU Shan-jun WANG Wei State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

The velocities at given points in the volute chamber,the contracted section and the vertical dropshaft of a discharge tunnel with vortex drop were measured by a small specially designed L-shaped tube,as Laser Doppler Velocimetry（LDV） or Particle Image Velocimetry（PIV） would not work there due to the special structure of the discharge tunnel with vortex *** empirical formulas were proposed to predict the velocities and the angles of the velocities made with the vertical direction θ.The theoretical analysis results were in good agreement with experimental ***,the method proposed in this paper can be used to analyze related characteristics of discharge tunnels with vortex ***,different model scales were considered to predict the cavitation characteristics on the wall of a dropshaft in practical engineering.

关键词： discharge tunnel with vortex drop dropshaft velocity wall pressure cavitation

Expression of Bcl-2 inhibited Fas-mediated apoptosis in human hepatocellular carcinoma BEL-7404 cells

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Cell Research 2000年第3期10卷 233-242页

作者： CHANG YUN CHAO, yong hua xu (Shanghai institute of Cell Biology, Chinese Academy of Sciences, 320 Yue-yang Road, Shanghai 200031, China) ShanghaiInstituteofCellBiology ChineseAcademyofSciences.

Apoptosis plays an important role in embryonic development, tissue remodeling, immune regulation and tumor regression. Two groups of molecules (Bcl-2 family and 'Death factor' family) are involved in regulating apoptosis. In order to know about the effect of Bcl-2 on apoptosis induced by Fas, a typical member of 'Death factor' family, the transfection experiments with expression vectors pcDNA3-fl and pcDNA3-bcl-2 were performed in BEL-7404 cells, a human hepatocellular carcinoma cell line which expresses endogenous Fas, but not FasL and Bcl-2. The data showed that the expression of FasL in pcDNA3-fl transfected hepatoma cells obviously induced the apoptosis of the cells. However, the overexpression of Bcl-2 in pcDNA3-bcl-2 transfected 7404/b-16 cells counteracted pcDNA3-fl transient transfection mediated apoptosis. Further study by cotransfection experiments indicated that Bid but not Bax (both were pro-apoptotic proteins of Bcl-2 family) blocked the inhibitory effect of Bcl-2 on Fas-mediated apoptosis. These results suggested that Fas-mediated apoptosis in human hepatoma cells is possibly regulated by Bcl-2 family proteins via mitochondria pathway.

关键词： Apoptosis FasL Bcl-2 Bid Bax human hepa- tocellular carcinoma cells.

Cloning and Sequence Analysis of the Full-length cDNA of a Novel yp05 Gene Associated With Citrinin Production in Monascus aurantiacus

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Biomedical and Environmental Sciences 2007年第2期20卷 135-140页

作者： yong-hua XIONG YANG xu WEI-hua LAI YAN-PIN LI hua WEI Sino-Germany Joint Research Institute National Key Laboratory of Food Science （Nanchang University） Ministry of Education Nanchang 330047 Jiangxi China

Objective To obtain the full-length cDNA of a novel gene （named yp05） associated with citrinin production-related genes in Monascus aurantiacus. Methods Total RNA was extracted from mycelium, 3＇ and 5＇ cDNA end of yp05 gene was amplified using smartTM trace cDNA amplification kit, and the full-length cDNA of a novel gene （named yp05） was obtained from the electronic assembly of 3＇-RACE and 5＇- RACE products. Results This yp05 gene was 787 bp including a 597 bp open reading frame （ORF） and encoded a deduced protein with 199 amino acid residues, and the amino acid sequence of this protein was found similar with the sequences of many fungal manganese-superoxide dismutases in the GenBank with the aid of BLASTp. The transcription ofyp05 gene in Monascus strains was analyzed with the aid of Northern blotting. The transcription of yp05 gene was only detected in Monascus strains, provided that citrinin was produced. Conclusion The transcription of yp05 gene belongs to differential expression genes of citfinin yielded from Monascus and has no correlation with the biosynthesis pathway of red pigments.

关键词： Monascus aurantiacus Citrinin RACE Manganese-superoxide dismutases

Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells

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Cell Research 2001年第2期11卷 101-106页

作者： GUO BEN CHANG, yong hua xu Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-yang Road, Shanghai 200031, China 1Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yue-yang Road Shanghai 200031 China 1Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yue-yang Road Shanghai 200031 China

Trail, a tumor necrosis factor-related apoptosis-inducing ligand, is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2. Its role, like FasL in activation-induced cell death (AICD), has been demonstrated in immune system. However the mechanism of Trail induced apoptosis remains nuclear. In this report, the recombinant Trail protein was expressed and purified. The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro. Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner. Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in BcL-2 gene transfected cells. Treatment with PMA (phorbol 12-myristate 13-acetate), a PKC activator, suppressed nail-induced apoptosis in Jurkat T cells. The inhibition of apoptosis by PMA was abolished by pretreatment with Bis, a PKC inhibitor. Taken together, it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell.

关键词： trail Jurkat T cells apoptosis Bcl-2 PEA PKC Bis.

Deregulated c-myc expression in quiescent CHO cellsinduces target gene transcription and subsequent apoptotic phenotype

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Cell Research 1999年第4期9卷 305-314页

作者： FANG CHANG MING CAN SHI yong hua xu(Laboratory of Molecular and Cellular Oncology, Shanghai)(Institute of Cell Biology, Chinese Academy of Sciences,320 Yue Yang Road, Shanghai 200031, China) Laboratory of Molecular and Cellular Oncology Shanghai Institute of Cell Biology Chinese Academy of Sciences 320 Yue Yang Road Shanghai 200031 China

INTRODUCTIONThec-mycproto--oncogene,thecellularhomologueofthegenebornbytheretrovirusMC29,isresponsibleforchickenleukemia[1],anditoriginallygotitsnamefortheabilitytocausemyelocytomatosisinsusceptibleanimalsandculturedc... 详细信息

关键词： c-myc CHO cell line apoptosis c-myctarget genes.

Down-regulated expression of atypical PKC-binding domain deleted asip isoforms in human hepatocellular carcinomas

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Cell Research 2001年第3期11卷 223-229页

作者： FANG CHANG MINC, yong hua xu Laboratory of Molecular and Cellular Oncology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China 1Laboratory of Molecular and Cellular Oncology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China. 1Laboratory of Molecular and Cellular Oncology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China.

Asip is a mammalian homologue of polarity protein Par-3 of Caenorhabditis elegans and Bazooka of Drosophila melanogaster. Asip/Par-3/Bazooka are PDZ-motif containing proteins that localize asymmetrically to the cell periphery and play a pivotal role in cell polarity and asymmetric cell division. In the present study, we have cloned human asip cDNA and its splicing variants by 5’-RACE and RT-PCR using candidate human EST clones which have a high homology to rat asip cDNA. The full-length cDNA of human asip encodes a 1,353 aa protein exhibiting 88% similarity to the rat one. Human asip is a single copy gene consisting of at least 26 exons and localizing in human chromosome 10, band p11.2, with some extraordinarily long introns. All exon/intron boundary nucleotides conform to the "gt-ag" rule. Three main transcripts were detected by Northern blot analysis, and at least five variants, from alternative splicing and polyadenylation, have been identified by RT-PCR and liver cDNA library screening. Exon 17b deleted asip mRNAs expressed ubiquitously in normal human tissues, including liver, on RT-PCR analysis. However, they were absent from most human liver cancer cell lines examined. More interestingly, the expression of exon 1 7b deleted variants was down regulated in 52.6% (10/19) clinic specimens of human hepatocellular carcinomas (HCCs), compared with the surrounding nontumorous liver tissues from the same patients. The presence of various splicing transcripts, the variation of their distribution among different tissues and cells, and their differential expressions in human HCCs suggest that human Asip isoforms may function in different context.

关键词： Alternative splicing and polyadenylation A sip/Par-3/Bazooka PDZ-motif protein Polarity protein hepatocellular carcinomas.

Delivery efficiency of periadventitial approach in comparison of intravascular delivery: an assessment of pharmacokinetics in porcine arteries

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中国介入影像与治疗学 2005年第5期2卷 319-324页

作者： yong-hua xu Gordon McLennan Department of Radiology Indiana University School of Medicine Indianapolis 46202 USA

Objective To investigate the delivery efficacy of periadventitial delivery of125I-iododeoxyuridine 125I-IUdR) in comparison of intravascular delivery to determine the optimal delivery method for inhibiting post-angioplasty restenosis. Methods In 8 pigs, one side carotid, subclavian and iliac arteries of each pig were injured by balloon angioplasty with a 20% overstretches. Then, 4 mCi of 125I-IUdR was delivered at each targeted vessel with periadventitial method in 4 pigs （periadventitial group） and with intravascular method via a porous balloon catheter in other 4 pigs （intravascular group）. The animals survived for 5 hours and the blood radioactivity was investigated prior to and hourly after procedure until sacrifice. The targeted vessels and renal arteries （for control） were harvested for gamma-counting and histological observation. Meanwhile, the radioactivity in thyroid, liver, bladder, small bowel and each kidney also were measured to determine the biodistribution of125I. The activities of125I presented in arterial and tissue specimens were compared between the two delivery groups. The targeted arteries were histologically observed and the ratio of intima to media （I∶M ratio） was calculated. Results The target arterial walls in the periadventitial group had 3.4 times as much of125I radioactivity as in the intravascular group, respectively （P=0.038）; the blood activity in intravascular group was significantly higher than periadventitial group immediate after procedure （P0.05）. The mean I: M ratios in both groups were 0.05 without additional injury at the vessel wall. Conclusion The periadventitial delivery offered substantial advantage over intravascular approach with high local delivery efficacy. The apparent redistribution rate is more rap

关键词：传输方式血管内传输药物代谢动力学猪动脉疾病

Scintillation Arc from FRB 20220912A

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee Dong-Zi Li Yuan-Pei Yang Fa-Yin Wang Rui Luo Pei Wang Chen-Hui Niu Heng xu Bo-Jun Wang Wei-Yang Wang yong-Kun Zhang Yi Feng De-Jiang Zhou yong-hua xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for Astrophysics and Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and Astrophysics California Institute of TechnologyPasadena 91125USA South-Western Institute For Astronomy Research Yunnan UniversityKunming 650504China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China CSIRO Space and Astronomy Epping 1710Australia Department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)20220912A during its extremely active episode in 2022using data from the Five-hundred-meter Aperture Spherical Radio Telescope(FAST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler *** arc indicates that the scintillation is caused by a highly localized *** analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy *** present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or *** methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 20220912A

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