• 제목/요약/키워드: sciences

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Molecular Cloning and Characterization of the Yew Gene Encoding Squalene Synthase from Taxus cuspidata

  • Huang, Zhuoshi;Jiang, Keji;Pi, Yan;Hou, Rong;Liao, Zhihua;Cao, Ying;Han, Xu;Wang, Qian;Sun, Xiaofen;Tang, Kexuan
    • BMB Reports
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    • 제40권5호
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    • pp.625-635
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    • 2007
  • The enzyme squalene synthase (EC 2.5.1.21) catalyzes a reductive dimerization of two farnesyl diphosphate (FPP) molecules into squalene, a key precursor for the sterol and triterpene biosynthesis. A full-length cDNA encoding squalene synthase (designated as TcSqS) was isolated from Taxus cuspidata, a kind of important medicinal plants producing potent anti-cancer drug, taxol. The full-length cDNA of TcSqS was 1765 bp and contained a 1230 bp open reading frame (ORF) encoding a polypeptide of 409 amino acids. Bioinformatic analysis revealed that the deduced TcSqS protein had high similarity with other plant squalene synthases and a predicted crystal structure similar to other class I isoprenoid biosynthetic enzymes. Southern blot analysis revealed that there was one copy of TcSqS gene in the genome of T. cuspidata. Semi-quantitative RT-PCR analysis and northern blotting analysis showed that TcSqS expressed constitutively in all tested tissues, with the highest expression in roots. The promoter region of TcSqS was also isolated by genomic walking and analysis showed that several cis-acting elements were present in the promoter region. The results of treatment experiments by different signaling components including methyl-jasmonate, salicylic acid and gibberellin revealed that the TcSqS expression level of treated cells had a prominent diversity to that of control, which was consistent with the prediction results of TcSqS promoter region in the PlantCARE database.

Development of a dual-mode energy-resolved neutron imaging detector: High spatial resolution and large field of view

  • Wenqin Yang;Jianrong Zhou;Jianqing Yang;Xingfen Jiang;Jinhao Tan;Lin Zhu;Xiaojuan Zhou;Yuanguang Xia;Li Yu;Xiuku Wang;Haiyun Teng;Jiajie Li;Yongxiang Qiu;Peixun Shen;Songlin Wang;Yadong Wei;Yushou Song;Jian Zhuang;Yubin Zhao;Junrong Zhang;Zhijia Sun;Yuanbo Chen
    • Nuclear Engineering and Technology
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    • 제56권7호
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    • pp.2799-2805
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    • 2024
  • Energy-resolved neutron imaging is an effective way to investigate the internal structure and residual stress of materials. Different sample sizes have varying requirements for the detector's imaging field of view (FOV) and spatial resolution. Therefore, a dual-mode energy-resolved neutron imaging detector was developed, which mainly consisted of a neutron scintillator screen, a mirror, imaging lenses, and a time-stamping optical fast camera. This detector could operate in a large FOV mode or a high spatial resolution mode. To evaluate the performance of the detector, the neutron wavelength spectra and the multiple spatial resolution tests were conducted at CSNS. The results demonstrated that the detector accurately measured the neutron wavelength spectra selected by a bandwidth chopper. The best spatial resolution was about 20 ㎛ in high spatial resolution mode after event reconstruction, and a FOV of 45.0 mm × 45.0 mm was obtained in large FOV mode. The feasibility was validated to change the spatial resolution and FOV by replacing the scintillator screen and adjusting the lens magnification.

Organ Specific Gene Expressions in C57BL6 Mice

  • Majumder, Zahidur Rahman;Lee, Woo-Jung;Kim, Dae-Yong;Jeoung, Doo-Il;Cho, Chul-Koo;Lee, Su-Jae;Bae, Sang-Woo;Lee, Yun-Sil
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 2004년도 추계학술발표회 발표논문집
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    • pp.1211-1211
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    • 2004
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Wild Carrot Oil Extract is Selectively Cytotoxic to Human Acute Myeloid Leukemia Cells

  • Tawil, Mirna;Bekdash, Amira;Mroueh, Mohammad;Daher, Costantine F.;Abi-Habib, Ralph J.
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권2호
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    • pp.761-767
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    • 2015
  • Background: In this study, we used Daucus carota oil extract (DCOE) to target acute myeloid leukemia (AML) cells. All the AML cell lines tested were sensitive to the extract while peripheral mononuclear cells were not. Analysis of mechanism of cell death showed an increase in cells positive for annexinV and for active caspases, indicating that DCOE induces apoptotic cell death in AML. Inhibition of the MAPK pathway decreased sensitivity of AML cells to DCOE, indicating that cytotoxicity may be dependent on its activity. In conclusion, DCOE induces selective apoptosis in AML cells, possibly through a MAPK-dependent mechanism.