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6篇 您的检索式:作者名="Qingyan Han"
    题名 作者 年代 出处 被引量
1De novo mutation in ATP6V1B2 impairs lysosome acidification and causes dominant deafness-onychodystrophy syndrome显示文摘Yongyi Yuan Jianguo Zhang Qing Chang Jin Zeng Feng Xin Jianjun Wang Qingyan Zhu Jing Wu Jingqiao Lu Weiwei Guo Xukun Yan Hui Jiang Binfei Zhou Qi Li Xue Gao Huijun Yuan Shiming Yang Dongyi Han Zixu Mao Ping Chen Xi Lin Pu Dai 2014Cell Research2014,24,11:13
2The transcription factor OpWRKY2 positively regulates the biosynthesis of the anticancer drug camptothecin in Ophiorrhiza pumila显示文摘The limited bioavailability of plant-derived natural products with anticancer activity poses major challenges to the pharmaceutical industry.An example of this is camptothecin,a monoterpene indole alkaloid with potent anticancer activity that is extracted at very low concentrations from woody plants.Recently,camptothecin biosynthesis has been shown to become biotechnologically amenable in hairy-root systems of the natural producer Ophiorrhiza pumila.Here,time-course expression and metabolite analyses were performed to identify novel transcriptional regulators of camptothecin biosynthesis in O.pumila.It is shown here that camptothecin production increased over cultivation time and that the expression pattern of the WRKY transcription factor encoding gene OpWRKY2 is closely correlated with camptothecin accumulation.Overexpression of OpWRKY2 led to a more than three-fold increase in camptothecin levels.Accordingly,silencing of OpWRKY2 correlated with decreased camptothecin levels in the plant.Further detailed molecular characterization by electrophoretic mobility shift,yeast one-hybrid and dual-luciferase assays showed that OpWRKY2 directly binds and activates the central camptothecin pathway gene OpTDC.Taken together,the results of this study demonstrate that OpWRKY2 acts as a direct positive regulator of camptothecin biosynthesis.As such,a feasible strategy for the over-accumulation of camptothecin in a biotechnologically amenable system is presented.Xiaolong Hao Chenhong Xie Qingyan Ruan Xichen Zhang Chao Wu Bing Han Jun Qian Wei Zhou Hans-Wilhelm Nutzmann Guoyin Kai 2021Horticulture Research2021,8,1:7
3Effect of diacylglycerol acyltransferase 2overexpression in 3T3-L1 is associated to an increase in mono-unsaturated fatty acid accumulation显示文摘Background:Fatty acid(FA) composition is the most important parameter affecting the flavor and nutritional value of the meat.The final and the only committed step in the biosynthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 2(DGAT2).The role of DGAT2 in lipid accumulation has been demonstrated in adipocytes,However,little is known about the effect of DGAT2 on the FA composition of these cells.Methods:To investigate the role of DGAT2 in regulating lipid accumulation,FA composition and the expression of adipogenic genes,we cloned the open reading frame of the porcine DGAT2 gene and established 3T3-L1 cells that overexpressed DGAT2.Cells were then cultured in differentiation medium(DM) without FA,with a mixture of FAs(FA-DM),or containing a ^(13)C stable isotope-labeled FA mixture(IFA-DM).The FA composition of adipocytes was analyzed by gas chromatography-mass spectrometry and gas chromatography-isotope ratio mass spectrometry.Quantitative PCR and western blotting were employed to detect expression of adipogenic genes in 3T3-L1 adipocytes cultured with FA-DM for 12 d.Results:The triacylglyceride(TAG) content was significantly higher in 3T3-L1 adipocytes overexpressing DGAT2 than in control cells.When cultured in DM or FA-DM for 12 d,cells overexpressing DGAT2 showed a higher proportion of unsaturated FAs(C16:1 and C18:1).However,when cells overexpressing DGAT2 were cultured with FA-DM for30 min,the FA composition was almost identical to that of controls.Further,the proportion of stable isotope-labeled FAs were similar in 3T3-L1 adipocytes overexpressing DGAT2 and control cells cultured in IFA-DM for 12 d.These results collectively indicate that the higher proportion of mono-unsaturated FAs,C16:1 and C18:1,may originate from de novo FA synthesis but not from the uptake of specific FAs from the medium.This hypothesis is further supported by evidence that both mRNA and protein expression of genes involved in FA synthesis(ACACA,FASN,SCD1,and A-FABP)were significantly higher in cells overexpressing DGAT2 than in control cells.Conclusions:In conclusion,our study revealed that TAG accumulation,the proportion of MUFAs,and the expression of adipogenic genes were higher in 3T3-L1 cells overexpressing DGAT2 than in control cells.Zhiqi Zhang Gang Shu Xiaotong Zhu Junming Guo Han Cai Songbo Wang Lina Wang Ping Gao Qianyun Xi Yongliang Zhang Li Yuan Qingyan Jiang 2014Journal of Animal Science and Biotechnology2014,5,4:3
4Synthesis of Ag-SiO_2 composite nanospheres and their catalytic activity显示文摘A simple,mild,and time-saving method is employed to synthesize Ag-SiO2 composite nanospheres with Ag nanoparticles uniformly distributed on the surface of SiO2 nanoparticles.The chemical elements and the morphology of Ag-SiO2 composite nanospheres were analyzed with transmission electron microscopy(TEM),X-ray power diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).On the surface of Ag-SiO2 composite nanospheres,silane coupling agent(KH-550)is introduced as an intermediary to connect the surfaces of SiO2 nanospheres and Ag nanoparticles,which is also helpful for avoiding the aggregation of Ag nanoparticles.It is found that Ag-SiO2 composite nanospheres have very good catalytic properties for the reduction of organic dyes,which may have potential application in wastewater treatment.HAN QingYan LI GuiAn WANG DeXuan HE EnJie DONG Jun GAO Wei LI JunNa LIU TingZhuo ZHANG ZhongYue ZHENG HaiRong 2014Science China Chemistry2014,57,6:2
5Enhancement of red upconversion emission intensity of Ho^(3+) ions in NaLuF4:Yb^(3+)/Ho^(3+)/Ce^(3+)@NaLuF_(4) core-shell nanoparticles显示文摘The red upconversion emission of Ho^(3+)ions,in the optical window of biological tissue,exhibits excellent prospects in biological applications.This study aims to enhance the red upconversion emission intensity of Ho^(3+)ions in NaLuF_(4):20%Yb^(3+)/2%Ho^(3+)/12%Ce^(3+) nanoparticles through building different core–shell structures with different excitation wavelengths.A significantly enhanced red upconversion emission with a higher red-to-green ratio was successfully obtained in NaLuF_(4):20%Yb^(3+)/2%Ho^(3+)/12%Ce^(3+)@NaLuF_(4) core–shell nanoparticles by introducing the Yb^(3+)and Yb^(3+)/Nd^(3+)ions into the NaLuF_(4) shell,with enhancement of the red emission occurring when Yb^(3+)and Nd^(3+)ions in the shell transfer more excitation energy to the Ho^(3+)ions.Investigation of the red emission enhancement mechanism is based on spectral characteristics and lifetimes.We examined the synergistic effect of dual-wavelength co-excitation NaLuF_(4):20%Yb^(3+)/2%Ho^(3+)/12%Ce^(3+)@NaLuF_(4):10%Yb^(3+)/15%Nd^(3+)core–shell nanoparticles to establish optimal excitation conditions.It is hoped that this method,using red upconversion emission core–shell nanoparticles with multi-mode excitation,can provide new ways to expand the applications of rare-earth luminescent materials in biomedicine and anti-counterfeiting.Wei Gao Xiaotong Cheng Yu Xing Shanshan Han Binhui Chen Qingyan Han Xuewen Yan Jihong Liu Lin Liu Jun Dong 2022Journal of Rare Earths2022,40,4:1
6Estimation of chlorophyll content in pepper leaves using spectral transmittance red-edge parameters显示文摘The objective of this work was to monitor the growth status of pepper and provide precise guidance on fertilization through non-destructive detection methods for chlorophyll content based on spectral transmittance.The analysis of the narrower red-edge spectral region(680-760 nm)reduced the requirements for light sources and light detection sensors,and provided a simpler and more accurate method of data acquisition for the process of developing instruments for estimating chlorophyll content in leaves.The red-edge region of spectral transmittance was demonstrated to be closely related to chlorophyll content.Regression models for estimating chlorophyll content with seven different methods were developed using the four red-edge parameters extracted from the red-edge region.The problems of multicollinearity of red-edge parameters and errors in model coefficients were solved by the ridge regression method in the process of building a multivariate regression model.The results indicated that the ridge regression method reduces the errors of the model coefficients and constant terms while improving the detection accuracy,thus the ridge regression model could estimate the leaf chlorophyll content more accurately and repeatedly.Shuai Huang You Wu Qinglan Wang Jingli Liu Qingyan Han Jianfeng Wang 2022International Journal of Agricultural and Biological Engineering2022,15,5:0
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