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A new Multilocus Sequence Analysis Scheme for Mycobacterium tuberculosis

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Biomedical and Environmental Sciences 2012年第6期25卷 620-629页

作者： LU bing DONG hai Yan zhao Xiu Qin LIU Zhi Guang LIU hai Can ZHANG Yuan Yuan JIANG Yi WAN Kang Lin State Key Laboratory for Infectious Diseases Prevention and Control National Institute for Communicable DiseaseControl and Prevention Chinese Center for Disease Control and Prevention & National Tuberculosis ReferenceLaboratory Beijing 102206 China

Objective Tuberculosis remains one of the most serious infectious diseases in the world. In this study, a scheme of Mycobacterium tuberculosis （M. tuberculosis） multilocus sequence analysis （MLSA） was established for the phylogenetic and epidemiology analysis. Methods To establish the scheme of M. tuberculosis MLSA, the genome of H37Rv, CCDC5079 and CCDC5180 were compared, and some variable genes were chosen to be the MLSA typing scheme. 44 M. tuberculosis clinical isolates were typed by MLSA, IS6110-RFLP, and soligotyping, to evaluate the MLSA methods. Results After comparison of the genome, seven high discrimination gene loci （recX, rpsL, rmlC, rpmG1, mprA, gcvH, ideR） were chosen to be the MLSA typing scheme finally. 11 variable SNP sites of those seven genes were found among the 44 M. tuberculosis isolate strains and 11 sequence types （STs） were identified. Based on the Hunter-Gaston Index （HGI）, MLSA typing was not as good for discrimination at the strain level as IS6110-RFLP, but the HGI was much better than that of spoligotyping. In addition, the MEGA analysis result of MLSA data was similar to spoligotyping/PGG lineage, showing a strong phylogenetic signal in the modern strains of M. tuberculosis. The MLSA data analysis by eBURST revealed that 4 sequence types （ST） came into a main cluster, showing the major clonal complexes in those 44 strains. Conclusion MLSA genotyping not only can be used for molecular typing, but also is an ideal method for the phylogenetic analysis for M. tuberculosis.

关键词： M. tuberculosis Multilocus sequence analysis Genotyping

Effects of genistein and equol on human and rat testicular 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase 3 activities

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Asian Journal of Andrology 2010年第4期12卷 519-526页

作者： Guo-Xin Hu bing-hai zhao Yan-Hui Chu Hong-Yu Zhou Benson T. Akingbemi Zhi-Qiang Zheng Ren-Shan Ge Population Council New York NY 10065 USA School of Pharmacy Wenzhou Medical College Wenzhou 325000 China Heilongjiang Key Laboratory of Anti-fibrosis Biotherapy Mudanjiang Medical University Mudanjiang 157001 China Departments of Anatomy Physiology and Pharmacology Auburn University Auburn AL 36849 USA The Second Affiliated Hospital Wenzhou Medical College Wenzhou 325000 China

The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. These enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. Genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. There was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.

关键词： 3β-hydroxysteroid dehydrogenase 17β-hydroxysteroid dehydrogenase 3 enzyme inhibition equol genistein

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang bing Zhang Lanfang Li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu Kai zhao Guoqiang Liu Youming Lu Xinyan Li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 922-930页

作者： Pu Xie hai-Yan zhao bing Wu Shui-Li Gong Department of Mechanical Engineering Tsinghua University State Key Laboratory of Tribology Tsinghua University Beijing Aeronautical Manufacture Technology Research Institute

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates（50 mm thick） by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS *** the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement *** test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld *** peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.

关键词： Electron beam welding Residual stress Finite element method Contour method Titanium alloy

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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Transcriptome approach to understand the potential mechanisms of resistant and susceptible alfalfa(Medicago sativa L.) cultivars in response to aphid feeding

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Journal of Integrative Agriculture 2018年第11期17卷 2518-2527页

作者： TU Xiong-bing zhao hai-long ZHANG Ze-hua State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Plant Protection Shenyang Agricultural University

Plant breeding for resistance to agricultural pests is an essential element in the development of integrated crop management systems, however, the molecular and genetic mechanisms underlying resistance are poorly understood. In this pilot study, we conducted a transcriptomic analysis of a resistant （R） and susceptible （S） variety of alfalfa, with （＋A） or without （-A） aphids （totally four treatments）. We used the resistant cultivar Zhongmu t and the susceptible cultivar Soca. A total of 3 549 mRNAs were differentially expressed, of which 1 738 up-regulated and 1 307 down-regulated genes were identified in S＋A/S-A plants, while 543 up-regulated and 331 down-regulated genes were identified in the R＋A/R-A plants. KEGG analysis mapped 112 and 546 differentially expressed genes to 8 and 17 substantially enriched pathways for Zhongmu 1 and Soca, respectively. Six shared pathways were linked to plant resistance traits, including phenylpropanoid biosynthesis associated with salicylic acid synthesis, and linoleic acid metabolism associated with both jasmonic acid and flavonoid biosynthesis. Ultimately, we proposed a preliminary regulatory mechanism of alfalfa cultivar resistance response to aphids feeding based on transcriptome analyses and published documents.

关键词： alfalfa cultivar resistance aphids transcriptomic molecular mechanism

Nebkhas play important roles in desertification control and biodiversity protection in arid and semi-arid regions of China

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Ecosystem Health and Sustainability 2020年第1期6卷 503-509,502页

作者： Weicheng Luo Wenzhi zhao bing Liu hai Zhou Linze Inland River Basin Research Station Chinese Ecosystem Research NetworkKey Laboratory of Ecohydrology of Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina

Nebkhas are isolated mounds vegetated with burial-tolerant desert plants that trap windborne sediment within their *** are critical to desertification control and biodiversity protection of oases in arid and semi-arid regions of China,as they(ⅰ)trap windborne sediments and ensure oasis security;(ⅱ)as“fertile islands,”nebkhas can trap and provide a suitable micro-environment for seeds,birds,and small soil animals,and increase biodiversity;(ⅲ)increase the soil surface roughness and significantly reduce soil erosion following heavy ***,the establishment of sand-fixing vegetation and over-grazing significantly limits the development and accelerate the degradation of nebkhas,threatening oasis *** provide background and recommendations for protective measures for nebkha landscapes in arid and semi-arid areas of China to aid managers in oasis protection.

关键词： Nebkha desertification control biodiversity protection human activities arid and semi-arid regions

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企业内部控制系统可控性原理应用初探

武汉科技大学学报（社会科学版） 2003年第1期5卷 20-23页

作者：李秉成赵海明陈群芳武汉科技大学管理学院湖北武汉430081

本文首先讨论了企业内部控制研究及实务存在的问题 ,然后 ,根据可控性原理。

关键词：可控性控制手段控制目标企业经济内部控制系统财务管理

Damage characteristics and new constitutive model of sandstone under wet–dry cycles

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Journal of Mountain Science 2022年第7期19卷 2111-2125页

作者： HUANG Zhen ZHANG Wei ZHANG hai ZHANG Jia-bing HU zhao-jian School of Civil Engineering and Architecture Guangxi UniversityNanning530004China Key Laboratory of Engineering Disaster Prevention and Structural Safety Guangxi UniversityNanning530004China

The mechanical properties of rock deteriorate under repeated wet-dry(WD)cycles,causing the deformation and failure of the rock mass.A reasonable damage constitutive model can truly reflect the whole process of rock deformation and ***,it is of great significance to study the damage characteristics and constitutive behaviour of rock subjected to numerous WD ***,sandstone from Tingliang tunnel was sampled for the WD cycle experiment,and uniaxial and triaxial tests were carried out on the rock samples after various numbers of WD cycles to analyze their macroscale damage ***,the damage mechanisms of the rock samples under the action of WD cycling were identified by X-ray diffraction(XRD)and scanning electron microscopy(SEM).Finally,based on the test data,the WD cycle-induced damage variable,Weibull distribution function,damage threshold,Drucker-Prager(D-P)yield criterion and residual strength correction coefficient were introduced,a wet-dry loading(WDL)constitutive damage model that considers the cracking stress of rock masses was established,and the expressions of the corresponding parameters were *** results show that an increasing number of WD cycles induces considerable variations in the macroscopic physical and mechanical parameters(such as the rock sample mass,saturated water content,longitudinal-wave velocity,compressive strength and elastic modulus),and the rate of change presents two stages,the inflection point of their rate of change is the 15th WD ***,the rock sample structure changes from intact and dense to fragmented and unconsolidated;additionally,the surface roughness increases,and the mineral composition *** established constitutive damage model exhibited good agreement with the experimental data;thus,this model can reflect the deformation and failure of rocks under WDL conditions,and the physical meaning of each parameter is clear.

关键词： Wet-dry cycle Sandstone Rock damage Constitutive model