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myocardial diastolic dysfunction by modulating Drp1-mediated mitochondrial fission and Ca homeostasis in a murinemodel of HFpEF

《医学前沿（英文）》 doi: 10.1007/s11684-023-0983-0

摘要： Berberine alleviates myocardial diastolic dysfunction by modulating Drp1-mediated mitochondrial fission and Ca homeostasis in a murine model of HFpEF

关键词： mitochondrial fission Ca     Berberine alleviates myocardial     murine model HFpEF    

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Gene and protein expression of proteinase-activated receptor-1, 2 in a murine model of acute graft host

Quan LI MD , Weiming LI MD , Ping ZOU MD , Jian ZHANG BM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 309-315 doi: 10.1007/s11684-009-0043-4

摘要： Proteinase-activated receptors (PARs) are a novel subclass of seven transmembrane-spanning, G protein-coupled receptors. PAR-1 and PAR-2 are widely expressed in a variety of cells and are found to be involved in many physiological and pathological processes including inflammation and immune response. However, little is known about the function of PAR-1, 2 in acute graft host disease (GVHD). In the present study, we first detected the expression of PAR-1, 2 protein and mRNA in a murine model of acute GVHD using the methods of immunohistochemistry, Western blot and quantitative real-time polymerase chain reaction (PCR). Syngeneic hematopoietic stem cell transplantation (HSCT) mice served as controls. The relative gene expression level of PAR-1 was significantly increased in the skin, liver, small intestine of allogeneic HSCT mice (in skin: 0.039±0.013 0.008±0.002 of controls, =0.009; in liver: 0.165±0.006 0.017±0.006 of controls, =0.004; in small intestine: 0.215±0.009 0.016±0.002 of controls, =0.003), but not in the stomach, lung and kidney of allogeneic HSCT mice (>0.05). PAR-2 mRNA expression in the liver and small intestine of allogeneic HSCT mice (in liver: 0.010±0.002 0.003±0.001 of controls, =0.008; in small intestine: 0.006±0.001 0.003±0.001 of controls, =0.024) was increased significantly, but PAR-2 mRNA expression in the other organs (>0.05) was not found to be significantly elevated. PAR-1, 2 protein expression was in accordance with the mRNA expression, as shown by Western blot. Using immunohistochemistry the present study demonstrated that there was strong PAR-1, 2 immunoreactivity in the epithelial cell and vascular endothelial cell of target organs of acute GVHD. Our findings of markedly increased expression of PAR-1, 2 in target organs of acute GVHD suggest that PAR-1 and PAR-2 may play an important role in the pathogenesis of acute GVHD.

关键词： graft vs host disease     proteinase-activated receptor     murine model     hematopoietic stem cell transplantation    

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4-1BBL expressed by eukaryotic cells activates immune cells and suppresses the progression of murine

Hui QIU, Hui ZHANG, Zuohua FENG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 20-25 doi: 10.1007/s11684-009-0006-9

摘要： The interaction by co-stimulatory molecules 4-1BB and 4-1BB ligand (4-1BBL) plays an important role in the activation, proliferation and differentiation of T lymphocytes. The function of 4-1BB/4-1BBL expressed by the immune cells has been the focus for many tumor immunotherapy efforts. In this study, 4-1BBL was expressed in non-immune cells and non-tumor cells, and the role of 4-1BBL in lymphocyte activation and tumor suppression was investigated. The plasmid p4-1BBL containing the full length of mouse 4-1BBL cDNA sequence was constructed, and the plasmid was transfected into baby hamster kidney (BHK) cells and murine muscle cells by means of lipofectin-mediated or naked plasmid DNA injection into the muscle directly. The study demonstrated that the molecule 4-1BBL expressed by BHK cells could enhance the proliferation and cytotoxicity of lymphocytes, and it could increase the expression level of IL-2 and IFN-γ. The treatment with plasmid p4-1BBL revealed that the number of CD8 T cells in the peri-tumoral tissue increased markedly, and the growth rate of the tumor was significantly lower than that of control group. These findings suggest that expression of 4-1BBL by normal cells in the tumor microenvironment can enhance the proliferation and other functions of T lymphocytes. This therapeutic method may provide a promising approach for tumor immunotherapy.

关键词： 4-1BB ligand     tumor immunotherapy     tumor microenvironment    

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Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic

Hongying ZHANG, Jianwu TANG, Wenting ZHU, Chunxiu HU, Guowang XU

《医学前沿（英文）》 2009年 第3卷 第2期   页码 119-129 doi: 10.1007/s11684-009-0022-9

摘要： In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells, a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential (Hca-P/L ) was established and the effect of curcumin on biological behavior of Hca-P/L was observed. Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential (Hca-P) was subcutaneously inoculated into the medioventral line of a mouse 615 and the first generation of metastatic tumor cells of inguinal lymph node (Hca-P/L ) was obtained. Then, Hca-P/L was screened by the route of mouse foot pad subcutaneously → lymph node → scale-up culture → mouse foot pad subcutaneously for five times consecutively. The sensitivity of two murine ascites hepatocarcinoma cell lines (Hca-P and Hca-P/L ) and two anchorage-dependent human hepatocarcinoma cell lines (SMC7721 and HepG ) to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after these cells had been pretreated by curcumin at the concentration of 15-240 μmol/L for 48 h. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 μmol/L , the effect of curcumin against cell proliferation of Hca-P and Hca-P/L was observed by inverted microscope, cell growth curve and cell population doubling time; the effects of curcumin on cell cycles of Hca-P/L and Hca-P were studied by flow cytometry (FCM). The results showed Hca-P/L spreading to the lymph nodes at multiple sites in mice was screened from Hca-P. The lymph node metastatic rate was 100%. Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner ( <0. 05). At concentrations of 30-120 μmol/L, curcumin had more inhibition on murine ascites hepatocarcinoma cell lines than on human anchorage-dependent hepatocarcinoma cell lines. At concentrations of 60-240 μmol/L, curcumin had more inhibition on Hca-P/L with (the 50% inhibitory concentration) IC of 51.48 μmol/L than on Hca-P with IC of 90.87 μmol/L. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days, the proliferations of Hca-P/L and Hca-P were inhibited ( <0.05) in a time-dependent manner ( <0.01) and the population doubling time of Hca-P/L and Hca-P was prolonged ( <0.01), and curcumin had more inhibition on Hca-P/L than on Hca-P ( <0.05). After pretreatment by 15 μmol/L curcumin for 48 h, the morphous of Hca-P/L was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L being blocked in the S phase and Hca-P in the S and G /M phases. Hca-P/L was validated to be more sensitive to curcumin than Hca-P. Hca-P/L is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.

关键词： murine ascites hepatocarcinoma cell line     metastasis     curcumin     drug sensitivity    

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Blockage of receptor-interacting protein 2 expression by small interfering RNA in murine macrophages

LIU Hongchun, CAO Zhongwei, JIN Jianjun, WANG Jiyao

《医学前沿（英文）》 2008年 第2卷 第2期   页码 166-170 doi: 10.1007/s11684-008-0030-1

摘要： This study aims to demonstrate that blocking the receptor-interacting protein2 (Rip2) expression can decrease inflammatory cytokine production by macrophage and protect mice from endotoxin lethality. Murine Rip2 small interfering RNA (siRNA) plasmids were constructed and transfected into macrophage and Rip2 expression was detected with reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Cell proliferation was assayed with MTT. TNF-? concentration was assayed with ELISA and high-mobility group box 1 protein (HMGB1) level with semi-quantitative western blot after lipopolysaccharide (LPS) stimulation. LPS challenge was given after the plasmids were injected into mice and the survival rate was calculated. Rip2 siRNA plasmid could block the mRNA and protein expression of Rip2 and promote cell proliferation. Blocking Rip2 could attenuate LPS-induced TNF-? and HMGB1 production. The HMGB1 expression in the liver decreased to (40.21 ± 11.03) pg/g, and serum TNF-? level decreased to (300.43 ± 59.26) ng/L ( < 0.05). The survival rate of mice from endotoxemia was also improved ( < 0.05). The results demonstrate that Rip2 siRNA plasmid can block the expression of Rip2, decrease the production of TNF-? and HMGB1 and protect mice from fatal endotoxemia.
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Immunotherapeutic effects on murine pancreatic carcinoma by β-elemene combined with dendritic cells modified

TAN Guang, WANG Zhongyu, CHE Luanqing, YIN Shuo

《医学前沿（英文）》 2007年 第1卷 第1期   页码 41-45 doi: 10.1007/s11684-007-0008-4

摘要： The dendritic cell vaccine is a treatment vaccine with potent clinical applications. Functional cytokines can enhance dendritic cell anti-tumor immune responses. This experiment was conducted to study the effects of bone marrow-deriv

关键词： Functional     experiment     anti-tumor     dendritic     clinical    

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Investigation on the mechanism of ginsenoside Rg3 in treating murine primary mammary tumor

Hongbo TANG MD, Zirong YE MM, Yuping REN MD, Zhanyong ZHU MD, Yiping WU MD,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 421-425 doi: 10.1007/s11684-009-0078-6

摘要： A murine primary mammary tumor model was established to investigate the treatment with ginsenosides Rg3. The relationship between ginsenosides Rg3 and primary mammary tumor was explored. Mammary tumor was induced by using the 7,12-dimethybenz(a)anthracene (DMBA). Ginsenoside Rg3 was employed for treatment. The incidence of mammary tumor in every group was compared, and the expressions of vascular endothelial growth factor (VEGF) and microvessel density (MVD) were detected by immunohistochemical method. The cell cycle and apoptosis percentage were determined by means of flow cytometry. The incidence of tumor in treatment group was significantly lower than that in control group (60.00% 33.33%, <0.05). The average diameter of mammary tumor was (0.86±0.27) cm in control group and (0.39±0.09) cm in treatment group, with the difference being significant between control and treatment groups (<0.01). The MVD value was (31.9±5.3) in control group and (20.1±4.9) in treatment group, respectively. There was a significant difference between the two groups (<0.05). The apoptosis percentage in control group was significantly lower than that in treatment group [(2.47±0.69)% (5.67±0.99)%, <0.05]. Ginsenoside Rg3 can play an antitumor role in primary mammary tumor model by inhibiting angiogenesis, cell cycle progression, and promoting cell apoptosis.

关键词： ginsenoside Rg3     mammary tumor     mice    

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Lentivector-mediated RNAi efficiently downregulates expression of murine cdk4 gene

Feng JIANG PhD , Xuezhen WANG PhD , Zheng XUE MD , Suming ZHANG PhD , Siyu FANG BM , Min ZHANG MD, PhD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 287-291 doi: 10.1007/s11684-009-0050-5

摘要： In order to explore the role of cyclin-dependent kinase 4 (cdk4) in neurodegenerative diseases, lentiviral-delivered RNA interference (RNAi) was used to silence the expression of the murine cdk4 gene . Three cdk4-shRNAs of mouse and a negative sequence were designed. After synthesis and annealing, double strand oligonucleotides were cloned into a linearized pSIH1-H1-copGFP shRNA vector. It was confirmed by polymerase chain reaction (PCR) and sequencing that three pairs of cdk4-shRNAs and a negative shRNA were correctly inserted into the pSIH1-H1-copGFP vector. The above recombinants were transfected by lipofectamine into BV-2 cells. The gene silencing efficacy rates of the 3 targets were compared by Western blotting. The cdk4-siRNA2 was the most effective in silencing cdk4. The optimized pSIH1-cdk4-siRNA2 and pSIH-negative-siRNA were co-transfected into 293T cells with the lentiviral packaging plasmids respectively. The culture supernatant was harvested and condensed at the 24th and 48thh after transfection. Interference efficiency of the lentivirus expressing cdk4-siRNA was determined by reverse transcriptase-PCR (RT-PCR) and Western blotting in BV-2 cells. Lentivector-mediated RNAi could efficiently down-regulate the expression of the murine cdk4 gene , which provides a potential tool for studying and treating cdk4-related diseases.

关键词： cyclin-dependent kinase 4     RNA interference     plasmid     lentiviral vector    

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Standard model of knowledge representation

Wensheng YIN

《机械工程前沿（英文）》 2016年 第11卷 第3期   页码 275-288 doi: 10.1007/s11465-016-0372-3

摘要：

Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

关键词： knowledge representation     standard model     ontology     system theory     control theory     multidimensional representation    

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受限空间火灾模型研究进展

郑昕,袁宏永

《中国工程科学》 2004年 第6卷 第3期   页码 68-74

摘要：

火灾模型是从工程科学的角度出发，分析研究火灾的发生、发展，烟气蔓延以及火灾对周围环境诸如建筑设备、森林植被及大气环境等影响的数学模型。介绍了广泛应用于建筑物内部受限空间的场、区域、网模型以及经验模型的理论思想与数学方程，分析了4种模型在相应环境下应用的合理性，并对火灾模型的发展做出了展望。

关键词： 受限空间     场模型     区域模型     网模型     场区网模型     经验模型    

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Elevated temperature creep model of parallel wire strands

《结构与土木工程前沿（英文）》   页码 1060-1071 doi: 10.1007/s11709-023-0981-y

摘要： Parallel wire strands (PWSs), which are widely used in prestressed steel structures, are typically in high-stress states. Under fire conditions, significant creep effects occur, reducing the prestress and influencing the mechanical behavior of PWSs. As there is no existing approach to analyze their creep behavior, this study experimentally investigated the elevated temperature creep model of PWSs. A charge-coupled camera system was incorporated to accurately obtain the deformation of the specimen during the elevated temperature creep test. It was concluded that the temperature level had a more significant effect on the creep strain than the stress level, and 450 °C was the key segment point where the creep rate varied significantly. By comparing the elevated temperature creep test results for PWSs and steel strands, it was found that the creep strain of PWSs was lower than that of steel strands at the same temperature and stress levels. The parameters in the general empirical formula, the Bailey–Norton model, and the composite time-hardening model were fitted based on the experimental results. By evaluating the accuracy and form of the models, the composite time-hardening model, which can simultaneously consider temperature, stress, and time, is recommended for use in the fire-resistance design of pre-tensioned structures with PWSs.

关键词： parallel wire strands     experimental study     elevated temperature creep model    

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Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

《工程管理前沿（英文）》 2018年 第5卷 第2期   页码 195-201 doi: 10.15302/J-FEM-2017052

摘要： In this work, we examine the impact of crude distillation unit (CDU) model errors on the results of refinery-wide optimization for production planning or feedstock selection. We compare the swing cut+ bias CDU model with a recently developed hybrid CDU model (Fu et al., 2016). The hybrid CDU model computes material and energy balances, as well as product true boiling point (TBP) curves and bulk properties (e.g., sulfur % and cetane index, and other properties). Product TBP curves are predicted with an average error of 0.5% against rigorous simulation curves. Case studies of optimal operation computed using a planning model that is based on the swing cut+ bias CDU model and using a planning model that incorporates the hybrid CDU model are presented. Our results show that significant economic benefits can be obtained using accurate CDU models in refinery production planning.

关键词： impact of model accuracy on production planning     swing cut+ bias CDU model     hybrid CDU model     refinery feedstock selection optimization     optimization of refinery operation    

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Test-driven verification/validation of model transformations

László LENGYEL,Hassan CHARAF

《信息与电子工程前沿（英文）》 2015年 第16卷 第2期   页码 85-97 doi: 10.1631/FITEE.1400111

摘要： Why is it important to verify/validate model transformations? The motivation is to improve the quality of the transformations, and therefore the quality of the generated software artifacts. Verified/validated model transformations make it possible to ensure certain properties of the generated software artifacts. In this way, verification/validation methods can guarantee different requirements stated by the actual domain against the generated/modified/optimized software products. For example, a verified/validated model transformation can ensure the preservation of certain properties during the model-to-model transformation. This paper emphasizes the necessity of methods that make model transformation verified/validated, discusses the different scenarios of model transformation verification and validation, and introduces the principles of a novel test-driven method for verifying/validating model transformations. We provide a solution that makes it possible to automatically generate test input models for model transformations. Furthermore, we collect and discuss the actual open issues in the field of verification/validation of model transformations.

关键词： Graph rewriting based model transformations     Verification/validation     Test-driven verification    

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Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-023-0748-0

摘要： One of the core challenges of intelligent fault diagnosis is that the diagnosis model requires numerous labeled training datasets to achieve satisfactory performance. Generating training data using a virtual model is a potential solution for addressing such a problem, and the construction of a high-fidelity virtual model is fundamental and critical for data generation. In this study, a digital twin-assisted dynamic model updating method for fault diagnosis is thus proposed to improve the fidelity and reliability of a virtual model, which can enhance the generated data quality. First, a virtual model is established to mirror the vibration response of a physical entity using a dynamic modeling method. Second, the modeling method is validated through a frequency analysis of the generated signal. Then, based on the signal similarity indicator, a physical–virtual signal interaction method is proposed to dynamically update the virtual model in which parameter sensitivity analysis, surrogate technique, and optimization algorithm are applied to increase the efficiency during the model updating. Finally, the proposed method is successfully applied to the dynamic model updating of a single-stage helical gearbox; the virtual data generated by this model can be used for gear fault diagnosis.

关键词： digital twin     gearbox     model construction     model updating     physical–virtual interaction    

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标题 作者 时间 类型 操作

myocardial diastolic dysfunction by modulating Drp1-mediated mitochondrial fission and Ca homeostasis in a murinemodel of HFpEF

期刊论文

Gene and protein expression of proteinase-activated receptor-1, 2 in a murine model of acute graft host

Quan LI MD , Weiming LI MD , Ping ZOU MD , Jian ZHANG BM ,

期刊论文

4-1BBL expressed by eukaryotic cells activates immune cells and suppresses the progression of murine

Hui QIU, Hui ZHANG, Zuohua FENG

期刊论文

Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic

Hongying ZHANG, Jianwu TANG, Wenting ZHU, Chunxiu HU, Guowang XU

期刊论文

Blockage of receptor-interacting protein 2 expression by small interfering RNA in murine macrophages

LIU Hongchun, CAO Zhongwei, JIN Jianjun, WANG Jiyao

期刊论文

Immunotherapeutic effects on murine pancreatic carcinoma by β-elemene combined with dendritic cells modified

TAN Guang, WANG Zhongyu, CHE Luanqing, YIN Shuo

期刊论文

Investigation on the mechanism of ginsenoside Rg3 in treating murine primary mammary tumor

Hongbo TANG MD, Zirong YE MM, Yuping REN MD, Zhanyong ZHU MD, Yiping WU MD,

期刊论文

Lentivector-mediated RNAi efficiently downregulates expression of murine cdk4 gene

Feng JIANG PhD , Xuezhen WANG PhD , Zheng XUE MD , Suming ZHANG PhD , Siyu FANG BM , Min ZHANG MD, PhD ,

期刊论文

Standard model of knowledge representation

Wensheng YIN

期刊论文

张正彦：融合知识的预训练语言模型（2020年4月3日）

2022年04月18日

会议视频

受限空间火灾模型研究进展

郑昕,袁宏永

期刊论文

Elevated temperature creep model of parallel wire strands

期刊论文

Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

期刊论文

Test-driven verification/validation of model transformations

László LENGYEL,Hassan CHARAF

期刊论文

Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

期刊论文