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Cationic liposome-mediated transfection of CD40 ligand gene inhibits hepatic tumor growth of hepatocellular carcinoma in mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 7-13页

作者： yong-fang JIANG Jing MA Yan HE yong-hong zhang Yun XU Guo-zhong GONG Center for Liver Diseases the Second Xiangya Hospital Central South University Changsha 410011 China

Objective: To evaluate the efficacy of cationic liposome-mediated CD40 ligand (CD40L) gene therapy for hepato- cellular carcinoma. Methods: 1×106 of parental H22 cells or H22 cells transfected with the expression vector containing murine CD40L cDNA encoding the entire coding region (pcDNA3.1+-mCD40L) were inoculated subcutaneously into the left flanks of syngenic BALB/C mice. The tumor-bearing mice (tumor nodules 10 mm in maximal diameter) received the treatment of the intratumoral injection of pcDNA3.1+-mCD40L/Transfectam, pcDNA3.1+, or phosphate-buffered saline (PBS), or no treatment. The mice were monitored for tumor growth weekly. We examined mCD40L messenger ribonucleic acid (mRNA) expression by reverse transcription polymerase chain reaction (RT-PCR) and the histologic changes in tumors at two weeks after intratumoral injection using immunohistochemical staining of tumor tissues. Results: All mice inoculated with parental H22 cells developed a tumor subcutaneously, and the tumor size increased progressively within three weeks. However, the mice receiving H22-CD40L cells exhibited complete regression of the tumor two weeks after tumor cell inoculation. The tumor-bearing animals with the treatment of pcDNA3.1+ or PBS, or without treatment had progressive tumor growth, while those mice treated with pcDNA3.1+-mCD40L exhibited a significant inhibition of tumor growth. RT-PCR analysis showed that 783-bp fragments cor- responding to the mCD40L mRNA were amplified only from pcDNA3.1+-mCD40L treated tumors. The tumor samples from pcDNA3.1+-mCD40L-treated mice showed significant lymphocyte infiltration, apoptotic bodies, and confluent necrosis in the tumor tissues. Conclusion: The tumorigenicity of CD40L-expressing cells was abrogated when the cells were implanted subcu- taneously. In vivo gene therapy of established liver tumor nodules in mice by the intratumoral injection of pcDNA3.1+-mCD40L led to significant tumor inhibition. There was mCD40L mRNA expression in the

关键词： CD40 ligand gene Hepatocellular carcinoma (HCC) Cationic liposome Transfection

Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1210-1220页

作者： Xiao-yong Gao hong Wei Li-feng zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion Mechanical property Anisotropy

Motor Fault Diagnosis Based on Short-time Fourier Transform and Convolutional Neural Network

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1357-1368页

作者： Li-Hua Wang Xiao-Ping Zhao Jia-Xin Wu Yang-Yang Xie yong-hong zhang School of Information and Control Nanjing University ofInformation Science and Technology Nanjing 210044 China School of Computer and Software Nanjing University ofInformation Science and Technology Nanjing 210044 China Network Monitoring Center of Jiangsu Province NanjingUniversity of Information Science and TechnologyNanjing 210044 China

With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and poor accuracy, when handling big data. In this study, the research object was the asynchronous motor in the drivetrain diagnostics simulator system. The vibration signals of different fault motors were collected. The raw signal was pretreated using short time Fourier transform （STFT） to obtain the corresponding time-frequency map. Then, the feature of the time-frequency map was adap- tively extracted by using a convolutional neural network （CNN）. The effects of the pretreatment method, and the hyper parameters of network diagnostic accuracy, were investigated experimentally. The experimental results showed that the influence of the preprocessing method is small, and that the batch-size is the main factor affecting accuracy and training efficiency. By investigating feature visualization, it was shown that, in the case of big data, the extracted CNN features can represent complex mapping relationships between signal and health status, and can also overcome the prior knowledge and engineering experience requirement for feature extraction, which is used by tra- ditional diagnosis methods. This paper proposes a new method, based on STFT and CNN, which can complete motor fault diagnosis tasks more intelligently and accurately.

关键词： Big data Deep learning Short-time Fouriertransform Convolutional neural network Motor

A New Ecdysteroid from Rhaponticum uniflorum

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Chinese Chemical Letters 2001年第9期12卷 797-798页

作者： yong hong zhang Xin Pu LI Zhi Gang LU Han Qing WANG Lanzhou Institute of Chemical Physics Chinese Academy of SciencesLanzhou 730000 Lanzhou Institute of Animal Science and Animal Medicine Lanzhou 730050

A new phytoecdysteroid was isolated from the root of Rhaponticum uniflorum. Its structure has been shown to be 2, 3, 20, 22-diacetonide ajugasterone.

关键词： Rhaponticum uniflorum compositae 2, 3, 20, 22-diacetonide ajugasterone

Conservation implications of population genetic structure in a threatened orchid Cypripedium tibeticum

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Plant Diversity 2019年第1期41卷 13-18页

作者： Jian-Ling Guo Wen-Juan Cao Zhi-Min Li yong-hong zhang Sergei Volis Life Science Department Yunnan Normal University Kunming Institute of Botany Chinese Academy of Sciences

Cypripedium tibeticum is a threatened orchid which efficient conservation requires knowledge of its extent and structure of genetic variation. Using two chloroplast DNA fragments(rps16 and trnL-F), we analyzed 157 individuals from 9 populations representing the species range in China. Seven haplotypes were identified. C. tibeticum had high total genetic diversity(H_T=0.80) with major contribution to this diversity made by among-population component(G_ST=0.64, Ф_ST= 0.86). However, despite high population differentiation there was no clear phylogeographic structure. The populations CY and DC made the greatest contribution to the total gene diversity as well as allelic richness. The possible mechanisms and implications of these findings for conservation of the species are discussed.

关键词： Cypripedium tibeticum Orchid genetic diversity Population differentiation East Himalaya-Hengduan mountains Conservation strategy

Experiences and Research Perspectives on Sustainable Development of Rice-Wheat Cropping Systems in the Chengdu Plain, China

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Agricultural Sciences in China 2010年第9期9卷 1317-1325页

作者： ZHENG Jia-guo CHI Zhong-zhi JIANG Xin-lu TANG yong-lu zhang hong Tillage and Cultivation Research Center Sichuan Academy of Agricultural Sciences Chengdu 610066 P.R.China

The rice and wheat cropping pattern is one of the main cropping systems in the world. A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption, gradual degeneration of soil fertility, decline of soil organic matter, and increased incidence of diseases and pests. In China, especially in the Chengdu plain where rice-wheat cropping system is practiced, productivity and soil fertility was enhanced and sustained. This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006. The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included： 1） creating a favorable environment and viable rotations; 2） balanced fertilization for maintenance of sustainable soil productivity; 3） improvement of crop management for higher efficiency; and 4） use the newest cultivars and cultivation techniques to upgrade the production level. Future research is also discussed in the paper as： 1） the constant topic： a highly productive and efficient rice-wheat cropping system for sustainable growth; 2） the future trend： simplified cultivation techniques for the rice-wheat cropping system; 3） the foundation： basic research for continuous innovation needed for intensive cropping. It is concluded that in the rice-wheat cropping system, a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity, but also maintain sustainable growth in the long run.

关键词： rice-wheat cropping system principle strategies rotation sustainable soil productivity simplification cultivation techniques Chengdu Plain

Two new triterpenoid saponins from Rhaponticum uniflorum

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Chinese Chemical Letters 2009年第6期20卷 690-693页

作者： yong hong zhang Ying Wu Li Yang Zhong Li Liu Dong Liang Cheng Department of Pharmacy Fujian Medical University Fuzhou 350004 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

Two new triterpenoid saponins were isolated from the roots ofRhaponticum uniflorum. Their structures were elucidated as 3-O- [β-D-glucopyranosyl]-ilexolic acid-28-O-[β-D-glucopyranosyl] ester 1 and 3-O-[β-D-glucopyranosyl]-urs-12, 19 （29）-dien-oic acid-28-O-[β-b-glucopyranosyl] ester 2 mainly by 1D, 2D NMR techniques and chemical methods.

关键词： Rhaponticum uniflorum Compositae Triterpenoid saponin

Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models

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Zoological Research 2024年第4期45卷 747-766页

作者： hong-Yi Zheng Tian-zhang Song yong-Tang Zheng State Key Laboratory of Genetic Evolution&Animal Models KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019(COVID-19)immunobiology,often resulting in a lack of reproducibility when extrapolated to the whole ***,developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** review summarizes current progress related to COVID-19 animal models,including non-human primates(NHPs),mice,and hamsters,with a focus on their roles in exploring the mechanisms of immunopathology,immune protection,and long-term effects of SARS-CoV-2 infection,as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 *** among these animal models and their specific applications are also highlighted,as no single model can fully encapsulate all aspects of *** effectively address the challenges posed by COVID-19,it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and *** animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic,serving as a robust resource for future emerging infectious diseases.

关键词： SARS-CoV-2 COVID-19 Animal models Infection immunology Immunotherapy

Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-Hai Ma Xiao-Chuan zhang Li-hong Han yong-hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test