期刊文献+
共找到1,585篇文章
< 1 2 80 >
每页显示 20 50 100
Advanced Machine Learning and Gene Expression Programming Techniques for Predicting CO_(2)-Induced Alterations in Coal Strength
1
作者 Zijian Liu Yong Shi +3 位作者 ChuanqiLi Xiliang Zhang Jian Zhou Manoj Khandelwal 《Computer Modeling in Engineering & Sciences》 2025年第4期153-183,共31页
Given the growing concern over global warming and the critical role of carbon dioxide(CO_(2))in this phenomenon,the study of CO_(2)-induced alterations in coal strength has garnered significant attention due to its im... Given the growing concern over global warming and the critical role of carbon dioxide(CO_(2))in this phenomenon,the study of CO_(2)-induced alterations in coal strength has garnered significant attention due to its implications for carbon sequestration.A large number of experiments have proved that CO_(2) interaction time(T),saturation pressure(P)and other parameters have significant effects on coal strength.However,accurate evaluation of CO_(2)-induced alterations in coal strength is still a difficult problem,so it is particularly important to establish accurate and efficient prediction models.This study explored the application of advancedmachine learning(ML)algorithms and Gene Expression Programming(GEP)techniques to predict CO_(2)-induced alterations in coal strength.Sixmodels were developed,including three metaheuristic-optimized XGBoost models(GWO-XGBoost,SSA-XGBoost,PO-XGBoost)and three GEP models(GEP-1,GEP-2,GEP-3).Comprehensive evaluations using multiple metrics revealed that all models demonstrated high predictive accuracy,with the SSA-XGBoost model achieving the best performance(R2—Coefficient of determination=0.99396,RMSE—Root Mean Square Error=0.62102,MAE—Mean Absolute Error=0.36164,MAPE—Mean Absolute Percentage Error=4.8101%,RPD—Residual Predictive Deviation=13.4741).Model interpretability analyses using SHAP(Shapley Additive exPlanations),ICE(Individual Conditional Expectation),and PDP(Partial Dependence Plot)techniques highlighted the dominant role of fixed carbon content(FC)and significant interactions between FC and CO_(2) saturation pressure(P).Theresults demonstrated that the proposedmodels effectively address the challenges of CO_(2)-induced strength prediction,providing valuable insights for geological storage safety and environmental applications. 展开更多
关键词 CO_(2)-induced coal strength meta-heuristic optimization algorithms XGBoost gene expression programming model interpretability
在线阅读 下载PDF
Cloning and Prokaryotic Expression of Canine IL-2 Gene
2
作者 FEI Dong-liang BI Cong-ming +1 位作者 SU Yu-gang BAI Ren 《Animal Husbandry and Feed Science》 CAS 2011年第1期30-32,共3页
[ Objective] To clone and express canine IL-2 gene and thus to provide theoretical support for the development of novel immune enhancers and genetic engineering vaccines. [ Method] Leukocytes separated from canine who... [ Objective] To clone and express canine IL-2 gene and thus to provide theoretical support for the development of novel immune enhancers and genetic engineering vaccines. [ Method] Leukocytes separated from canine whole blood were stimulated by concanavalin for 20 h, and then total RNA was extracted. According to the sequence of canine IL-2 gene published in the GenBank, a pair of primers was designed. After PCR am- plificetion, the target fragment was cloned into prokaryotic expression vector pET-28a. The recombinants were transformed into the host bacteria BL21. After IPTG induction, the expression products were analyzed by SDS-PAGE. [ Result] A 500 bp band with the expected size appeared in the RT-PCR products. After the pMD18-T-IL2 was identified by double digestion, an approximately 500 bp fragment was produced, which indicated successful cloning of the gene. After the pET-28a-lL2 was identified by restriction enzyme digestion and PCR, a 500 bp fragment was produced, which indicated successful construction of the expression vector. As revealed by the SDS-PAGE analysis, a protein band with molecular weight of about 20 kDa appeared. [ Conclusion] The canine IL-2 gene was cloned and expressed. 展开更多
关键词 CANINE INTERLEUKIN-2 gene cloning Prokaryotic expression
在线阅读 下载PDF
Effects of Light and Temperature on the Expression of the Lhcb2 Gene in Pea 被引量:6
3
作者 孙钦秒 李良璧 +2 位作者 阎久胜 毛大璋 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第3期258-262,共5页
An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting usi... An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting using special probe demonstrated that there existed one copy of Lhcb 2 in pea genome. RT_PCR and Northern blotting revealed the expression of Lhcb 2 which was regulated by light in a time_dependent expression manner. The Lhcb 2 gene didn't express untill 2 h after irradiated with white light. Low temperature (4 ℃) also affected the Lhcb 2 gene by decreasing half of its expression under 25 ℃. 展开更多
关键词 PEA Lhcb 2 gene light and temperature expression
在线阅读 下载PDF
Analysis of Seed-specificity of Silencing fad_2 Gene Expression in Transgenic Rapeseed Line W-4(Brassica napus L.) 被引量:3
4
作者 陈松 彭琦 +5 位作者 周晓婴 高建芹 张维 张洁夫 浦惠明 戚存扣 《Agricultural Science & Technology》 CAS 2014年第8期1308-1311,1316,共5页
This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different deve... This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different developmental stages of 7th, 14th, 21st and 28th day after flowering (DAF) as wel as the root, stem, leaf at winter seedling stages of both the transgenic line W-4 and non-transgenic control Westar by real-time fluorescence quantitative PCR. [Results] The results showed the relative expression of fad2 gene was gradual y increasing with the days after flowering in the seeds of the control Westar, while it was found decreasing significantly since the 21st DAF in the seeds of the line W-4. The decline was up to 60% in comparison with the control Westar. However, no significant difference in the relative expression of fad2 gene in other organs like root, stem and leaf was observed between transgenic line W-4 and non-transgenic control Westar. Fatty acid composition analysis showed the oleic acid desaturation parameter(ODP) in seeds of the line W-4 was 0.07 in average, decreased by nearly 75% than control Westar which was 0.24 in average, while no significant difference in the seedling root, stem and leaf was measured between transgenic rapeseed and control. [Conclusion] The results above validated that RNA interference in transgenic rapeseed W-4 is at a seed-specific manner, not interfering with fad2 gene expression in organs such as the root, stem and leaf. The study also found that the period of fad2 gene expres-sion decline was wel coincided with the expression of napin gene, both appeared at the 21st DAF, indicating that the expression of dsRNA of fad2 gene is precisely control ed by the napin promoter. 展开更多
关键词 Transgenic rapeseed Real-time fluorescence quantitative PCR fad2gene Specific expression
在线阅读 下载PDF
The Role of Predominant Expression of Th2 Type Cytokines Gene in the Genesis and Development of Human Gliomas 被引量:1
5
作者 李刚 胡永生 +3 位作者 李新钢 张庆林 贾德泽 宫崧峰 《The Chinese-German Journal of Clinical Oncology》 CAS 2003年第4期227-230,252,253,共6页
Objective: To explore the expression of Th1/Th2 cytokines gene in human gliomas and its role in the genesis and development of human gliomas.Methods: Using IL-2 and IFNγ as Th1 type cytokines, IL-4, IL-6 and IL-10 as... Objective: To explore the expression of Th1/Th2 cytokines gene in human gliomas and its role in the genesis and development of human gliomas.Methods: Using IL-2 and IFNγ as Th1 type cytokines, IL-4, IL-6 and IL-10 as Th2 type cytokines, the biological activity of cytokines in the supernatant of glioma cell lines was assayed by ELISA method, and the gene expression of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines were detected by RT-PCR.Results: There was predominant expression of Th2 type cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines, but there was no such expression in normal brain tissues.Conclusion: It suggested that there is a relationship between the Th2 type cytokines expression in human gliomas and the immunosupressive status of human glioma patients. The predominant expression of Th2 type cytokines may play an important role in the genesis and development of human gliomas. Key words glioma - Th1/Th2 - gene expression - RT-PCR This project was supported by a grant from National Natural Sciences foundation of China (No. 30271335). 展开更多
关键词 GLIOMA TH1/TH2 gene expression RT-PCR
暂未订购
SNP Identification in α_(2A)-Adrenergic Receptor Gene in Chinese and the Effect on Gene Expression
6
作者 袁栎 沈士弼 罗超权 《Journal of Nanjing Medical University》 2003年第6期277-282,共6页
Objective: To scan single nucleotide polymorphism ( SNP ) in Chinese alpha-2Aadrenergic receptor (α_(2A)-AR) gene and study the effects of the SNP on the gene expression.Methods: The complete sequence of α_(2A)-AR g... Objective: To scan single nucleotide polymorphism ( SNP ) in Chinese alpha-2Aadrenergic receptor (α_(2A)-AR) gene and study the effects of the SNP on the gene expression.Methods: The complete sequence of α_(2A)-AR gene was analyzed with automated DNA sequencer to scanSNPs. Genomic DNA was extracted from whole blood and a 239 bp fragment containing the G/Cpolymorphism was amplified with PCR using a pair of. specific primers. PCR-RFLP was used to performthe genotyping of the SNP at the site-1 296 bp of the people in the North of China. Electrophoresismobility shift assay ( EMSA ) was used to study the binding of the 390 bp fragments (- 1 414-1 025bp) with G or C at the site-1 296 bp and nuclear extracts . Results: In our study, two SNPs werefound in α_(2A)-AR gene. Allele frequencies of the SNP at the site-1 296 bp were 0.61 and 0.39 forG and C , and the genotype frequencies were 0.34 , 0.54 and 0.13 for GG, GC and CC respectively fromthe people in the North of China. In the EMSA, a specific binding appeared in the complex ofnuclear extracts and DNA with C at-1 296 bp . Conclusion: Two SNPs exist in α_(2A)-AR gene from thepeople in the North of China , and DNA fragment with allele C of the SNP at the site-1 296 bp couldbind with a specific protein, which could influence the gene expression. 展开更多
关键词 α_(2A)-adrenergic receptor single nucleotide polymorphism gene expression
暂未订购
Study on the effect of doxorubicin on expressions of genes encoding myocardial sarcoplasmic reticulum Ca^2+ transport proteins and the effect of taurine on myocardial protection in rabbits 被引量:12
7
作者 黄先玫 朱卫华 康曼丽 《Journal of Zhejiang University Science》 CSCD 2003年第1期114-120,共7页
To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca 2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits... To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca 2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits were injected with DOX , 8 rabbits with DOX and Tau, and 9 rabbits with normal saline. Cardiac function , concentration of calcium in cardiomyocytes (Myo[Ca 2+ ] \%i\%), activity of SR Ca 2+ ATPase(SERCA2a), level of SERCA2a mRNA and Ca 2+ released channels(RYR2)mRNA were detected. The left ventricle tissues were observed by electron microscopy. The results showed that cardiac index, left ventricular systolic pressure, activity of SR Ca 2+ ATPase and level of SERCA2a mRNA decreased , while Myo[Ca 2+ ] \%i\% increased in DOX treated rabbits. DOX could not affect the level of RYR2 mRNA. Tau intervention could alleviate the increase of left ventricular diastolic pressure, Myo[Ca 2+ ] \%i\% and the decrease of SERCA2a mRNA induced by doxorubicin. The results suggested that downregulation of SERCA2a gene expression was an important mechanism of DOX induced cardiomyopathy and that Tau could partially improve the heart function by reducing calcium overload and alleviating downregulation of SERCA2a mRNA. 展开更多
关键词 DOXORUBICIN Ca 2+ ATPase Ryanodine receptor TAURINE gene expression
暂未订购
Expression of MTA2 Gene in Ovarian Epithelial Cancer and Its Clinical Implication 被引量:8
8
作者 冀予心 张萍 +1 位作者 卢运萍 马丁 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第3期359-362,共4页
In order to investigate the roles of MTA2 in the pathogenesis of ovarian epithelial cancer, the expression of MTA2 in 4 ovarian cell lines were detected by semi-quantitative RT-PCR and Western-blot assays. MTA2 expres... In order to investigate the roles of MTA2 in the pathogenesis of ovarian epithelial cancer, the expression of MTA2 in 4 ovarian cell lines were detected by semi-quantitative RT-PCR and Western-blot assays. MTA2 expression in normal, borderline, benign and malignant epithelial ovarian tissues was immunohistochemically examined. The expression of MTA2 mRNA and protein was detected in all of 4 cell lines of ovarian epithelial cancer. The expression of MTA2 mRNA and protein was higher in strong migration cell lines than in weak migration ones. In borderline and ma lignant ovarian tissues tested, MTA2 staining was dramatically stronger than in normal and benign tissues (P〈0. 01). The expression levels in malignant ovarian tissues were significantly higher than that in borderline epithelial ovarian tissues (P〈0.01). The expression of MTA2 was correlated with clinical stage, histopathological grade and lymph node metastasis. It was concluded that the high expression of MTA2 was associated with more aggressive behaviors of epithelial ovarian cancer. MTA2 provides a novel indicator of ovarian cancer. 展开更多
关键词 MTA2 ovarian cell lines ovarian tumor gene expression IMMUNOHISTOCHEMISTRY
暂未订购
Gene expression and MR diffusion-weighted imaging after chemoembolization in rabbit liver VX-2 tumor model 被引量:5
9
作者 You-Hong Yuan En-Hua Xiao +6 位作者 Jian-Bin Liu Zhong He Ke Jin Cong Ma Jun Xiang Jian-Hua Xiao Wei-Jian Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第36期5557-5563,共7页
AIM: To investigate the dynamic characteristics and the correlation between PCNA, Bax, nm23, E-cadherin expression and apparent diffusion coefficient (ADC) on MR diffusion-weighted imaging (DWI) after chemoembolizatio... AIM: To investigate the dynamic characteristics and the correlation between PCNA, Bax, nm23, E-cadherin expression and apparent diffusion coefficient (ADC) on MR diffusion-weighted imaging (DWI) after chemoembolization in rabbit liver VX-2 tumor model. METHODS: Forty New Zealand rabbit liver VX-2 tumor models were included in the study. DWI was carried out periodically after chemoembolization. All VX-2 tumor samples in each group were examined by histopathology and Strept Avidin-Biotin Complex (SABC) immunohistochemical staining. RESULTS: The PCNA expression index in VX-2 tumors was higher than in the normal parenchyma around the tumor (P < 0.001). Nm23, Bax or E-caderin expression index in VX-2 tumors were lower than in the normal parenchyma around the tumor (all P < 0.001). PCNAand nm23 expression in the VX-2 tumor periphery first increased and then decreased (P < 0.001 and P = 0.03, respectively), while the expression of Bax and E-cadherin before and after chemoembolization was insignificant. When b-value was 100 s/mm2, there was a linear correlation between PCNA expression and ADC in the area of VX-2 tumor periphery (P < 0.001), and PCNA expression in VX-2 tumor periphery influenced the ADC. CONCLUSION: The potential of VX-2 tumor infiltrating and metastasizing decreases, while its ability to proliferate increases for a short time after chemoembolization. To some degree, the ADC value indirectly reflects the proliferation of VX-2 tumor cells. 展开更多
关键词 Rabbit liver VX-2 tumor CHEMOEMBOLIZATION Diffusion-weighted imaging gene expression
暂未订购
EXPRESSION AND SWITCHING OF TH1/TH2 TYPE CYTOKINESGENE IN HUMAN GLIOMAS 被引量:5
10
作者 Gang Li Yong-sheng Hu +3 位作者 Xin-gang Li Qing-lin Zhang Dong-hai Wang Song-feng Gong 《Chinese Medical Sciences Journal》 CAS CSCD 2005年第4期268-272, ,共5页
Objective To study the expression and switching of Thl/Th2 cytokines gene in human gliomas and its effects on occurring and developing of human gliomas. Methods Interleukin(IL)-2 and interferon-3, represent Thl typ... Objective To study the expression and switching of Thl/Th2 cytokines gene in human gliomas and its effects on occurring and developing of human gliomas. Methods Interleukin(IL)-2 and interferon-3, represent Thl type cytokines. IL-4, IL-6, IL-10, and IL-13 represent Th2 type cytokines. The gene expressions of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes, and glioma cell lines were detected by reverse transcription polymerase chain reaction (RT-PCR). The biological activity of cytokines in the supematant of glioma cell lines was assayed by enzyme-linked immunosorbent assay (ELISA) method. Results The total positive rates of Th1 and Th2 type cytokines gene in human glioma cells were 14.77% and 75%. The total positive rates of Th1 and Th2 type cytokines gene in glioma infiltrating lymphocytes were 22.73% and 68.17%. There was obviously predominant expression of Th2 type cytokines in human glioma tissues, glioma infiltrating lymphocytes, and glioma cell lines. There was no unbalanced expression of Th1/Th2 cytokines in normal brain tissues. Conclusion There is a predominant expression of Th2 type cytokines in human glioma cells. The switching of Th1/Th2 cytokines gene may play an important role in the occurring and developing of human gliomas. 展开更多
关键词 GLIOMA CYTOKINE TH1/TH2 gene expression
暂未订购
Expression Pattern of Testis-specific Expressed Gene 2 in Cryptorchidism Model and Its Role in Apoptosis of Spermatogenic Cells 被引量:2
11
作者 胡涛 王智宇 +4 位作者 曾甫清 陈晓春 顾朝辉 郑丽端 童强松 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第2期193-197,共5页
In our previous study, we identified a novel testis-specific expressed gene 2 (TSEG-2) from mouse testis. To further investigate its functions, 35 male Balb/c mice (8 weeks old) were divided into cryptorchidism gr... In our previous study, we identified a novel testis-specific expressed gene 2 (TSEG-2) from mouse testis. To further investigate its functions, 35 male Balb/c mice (8 weeks old) were divided into cryptorchidism group (n=20), sham group (n=10), and control group (n=5). In cryptorchidism group, the right testes were anchored to the inner lateral abdominal wall. In situ hybridization (ISH) was applied to measure the localization of TSEG-2 in mouse testis. Real-time quantitative PCR was performed to detect the expression of TSEG-2 gene. Meanwhile, under the mediation of polyethylenimine (PEI), the recombinant vector pEGFP-TSEG-2 (n=5) or empty vector (mock, n=5) was transfected into the testis of male mice. The transfection efficiencies were measured under a fluorescence microscope. The apoptosis of spermatogenic cells was detected by terminal deoxynuleotidyl-mediated nick end labeling (TUNEL). The results showed that TSEG-2 was expressed in convoluted seminiferous tubules, more precisely, in spermatogonia and spermatocytes. As compared with sham and control groups, the TSEG-2 transcription was significantly enhanced (P〈0.05) and was correlated with apoptosis of spermatogenic cells in cryptorchid testes (P〈0.05). PEI was efficient in mediating transfeetion of TSEG-2 into seminiferous tubules of testis. One week post-transfection, intratesticular injection of TSEG-2 resulted in increased apoptosis of spermatogenic cells in vivo (P〈0.05). These results indicate that TSEG-2 may participate in the apoptosis of spermatogenic cells and the pathogenesis of cryptorchidism. 展开更多
关键词 animal model testis-specific expressed gene 2 polyethylenimine APOPTOSIS
暂未订购
Expression and Chromosomal Mapping of Mouse Gpx2 Gene Encoding the Gastrointestinal Form of Glutathione Peroxidase, GPX-GI 被引量:5
12
作者 FONG-FONG CHU R. STEVEN ESWORTHY +4 位作者 YE SHIH HO MARGIT BERMEISTER KRISTINE SWIDEREK AND ROSEMARY W. ELLIOTT(Department of Medical Oncology, City of Hope Midical Center, Duarte,CA91010, USA Department of Psychiatry and Human Genetics,Mintal Health Research 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第2期156-162,共7页
GPX-GI is a cytosolic tetrameric Se-dependent glutathione peroxidase, similar in properties to GPX-1. Unlike the almost ubiquitous GPX-1, GPX-GI is mainly expressed in the epithelium of gastrointestinal tract. GPX-GI ... GPX-GI is a cytosolic tetrameric Se-dependent glutathione peroxidase, similar in properties to GPX-1. Unlike the almost ubiquitous GPX-1, GPX-GI is mainly expressed in the epithelium of gastrointestinal tract. GPX-GI contributes to at least fifty percent of GPX activity in rodent small intestmal epithelium. The total GPX activity consists of at least 70% of selenium-dependent GPX activity in this compartment.By analyzing a panel of mouse mterspecies DNA from the Jackson Laboratory's backcross resource,we mapped Gpx2 gene to mouse chromosome 12 between D12Mit4 and D12Mit5, near the Ccs1 locus which contains a colon cancer susceptibility gene. A pseudogene, Gpx2-ps is mapped to mouse chromosome 7.Comparison of Gpx2 gene expression in three pairs of C57BL/6Ha and ICR/Ha mice which are respectively resistant and sensitive to dimethylhydrazine-induced colon cancer, we found a higher Gpx2 mRNA level in C57BL/6Ha colon than ICR/Ha colon. Interestingly, a lower level of GPX activity is found in the resistant strain of mice. Because GPX-1 has three times higher specific activity than GPX GI, our data suggest that the decreased GPX activity may result from a higher level of Gpx2 gene expression in those cells co-express GPx1 gene 展开更多
关键词 GPX-GI GPx gene FORM expression and Chromosomal Mapping of Mouse Gpx2 gene Encoding the Gastrointestinal Form of Glutathione Peroxidase GI
在线阅读 下载PDF
Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells 被引量:16
13
作者 GuoBC XuYU 《Cell Research》 SCIE CAS CSCD 2001年第2期101-106,共6页
Trail, a tumor necrosis factor-related apoptosis-inducing ligand, is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2. Its role... Trail, a tumor necrosis factor-related apoptosis-inducing ligand, is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2. Its role, like FasL in activation-induced cell death (AICD), has been demonstrated in immune system. However the mechanism of Trail induced apoptosis remains unclear. In this report, the recombinant Trail protein was expressed and purified. The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro. Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner. Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in Bcl-2 gene transfected cells. Treatment with PMA (phorbol 12-myristate 13-acetate), a PKC activator, suppressed Trail-induced apoptosis in Jurkat T cells. The inhibition of apoptosis by PMA was abolished by pretreatment with Bis, a PKC inhibitor. Taken together, it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell. 展开更多
关键词 Apoptosis Apoptosis Regulatory Proteins CARCINOGENS gene expression Regulation Humans INTERLEUKIN-2 Jurkat Cells LIPOPOLYSACCHARIDES Membrane Glycoproteins Protein Kinase C Proto-Oncogene Proteins c-bcl-2 Recombinant Proteins Research Support Non-U.S. Gov't Tetradecanoylphorbol Acetate TRANSFECTION Tumor Necrosis Factor-alpha
暂未订购
HepG2 cells support viral replication and gene expression of hepatitis C virus genotype 4 in vitro 被引量:2
14
作者 Mostafa K El-Awady Ashraf A Tabll +9 位作者 Yasmine S El-Abd Mahmoud M Bahgat Hussein A Shoeb Samar S Youssef Noha G Bader El Din El-Rashdy M Redwan Maha El-Demellawy Moataza H Omran Wael T El-Garf Said A Goueli 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第30期4836-4842,共7页
AIM: TO establish a cell culture system with longterm replication of hepatitis C virus (HCV) genome and expression of viral antigens in vitro. METHODS: HepG2 cell line was tested for its susceptibility to HCV by i... AIM: TO establish a cell culture system with longterm replication of hepatitis C virus (HCV) genome and expression of viral antigens in vitro. METHODS: HepG2 cell line was tested for its susceptibility to HCV by incubation with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various time points during the culture. Culture supernatant was tested for its ability to infect na'ive cells. The presence of minus (antisense) RNA strand, and the detection of core and E1 antigens in cells were examined by RT-PCR and immunological techniques (flow cytometry and Western blot) respectively. RESULTS: The intracellular HCV RNA was first detected on d 3 after infection and then could be consistently detected in both cells and supernatant over a period of at least three months. The fresh cells could be infected with supernatant from cultured infected cells. Flow cytometric analysis showed surface and intracellular HCV antigen expression using in house made polyclonal antibodies (anti-core, and anti-E1). Western blot analysis showed the expression of a cluster of immunogenic peptides at molecular weights extended between 31 and 45 kDa in an one month old culture of infected cells whereas this cluster was undetectable in uninfected HepG2 cells. CONCLUSION: HepG2 cell line is not only susceptible to HCV infection but also supports its replication in vitro. Expression of HCV structural proteins can be detected in infected HepG2 cells. These cells are also capable of shedding viral particles into culture media which in turn become infectious to uninfected cells. 展开更多
关键词 Hepatitis C virus In vitro propagation Genomic replication gene expression HepG2 cells
暂未订购
HER2 gene status and the relationship with p21 protein expression in gastric cancer 被引量:3
15
作者 Yongjie Li Yangkun Wang +4 位作者 Xianwei Zhang Fulin Li Nianlong Meng Xutao Yuan Jinsheng Song 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第3期162-165,共4页
Objective: We aimed to analysis the HER2 gene status and its relationship with p21 protein expression in gastric carcinoma. Methods: Fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) techn... Objective: We aimed to analysis the HER2 gene status and its relationship with p21 protein expression in gastric carcinoma. Methods: Fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) techniques were used to detect HER2 gene status and p53 protein in 59 cases of gastric cancer. Results: FISH detection of HER2 gene amplification rate was 16.9% (10/59), HER2 gene amplification in 49 cases without copy number gain and gene amplification were a total of 49.2% (29/59). HER2 protein expression was 42.4% (25/59), HER2 gene amplification rates in patients with +++, ++ HER2 protein expression were 3/3 and 5/8, while in patients with + HER2 protein expression, it was 2/14, there was significant difference (P 0.05). p21 protein expression rate was 49.2% (29/59), HER2 gene amplification rates and p21 protein expression had significant difference in tumor invasion depth, lymph node metastasis (P 0.05); had no statistical significance in histological type, age, gender differences (P 0.05). Conclusion: HER2 gene amplification rate and gene copy number had positively correlation with p21 protein expression, HER2 gene status and expression of p21 protein combined detection can provide a reference value in gastric cancer metastasis, patient’s condition development and prognosis, it also can guide clinical development of individual treatment. 展开更多
关键词 stomach cancer HER2 gene p21 protein expression
在线阅读 下载PDF
Liver expression of Nrf2-related genes in different liver diseases 被引量:9
16
作者 Ming-Liang Cheng Yuan-Fu Lu +2 位作者 Hong Chen Zhong-Yang Shen Jie Liu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2015年第5期485-491,共7页
BACKGROUND: The KEAP1-Nrf2 antioxidant signaling pathway is important in protecting liver from various insults. However,little is known about the expression of Nrf2-related genes in human liver in different diseases.... BACKGROUND: The KEAP1-Nrf2 antioxidant signaling pathway is important in protecting liver from various insults. However,little is known about the expression of Nrf2-related genes in human liver in different diseases.METHODS: This study utilized normal donor liver tissues(n=35), samples from patients with hepatocellular carcinoma(HCC, n=24), HBV-related cirrhosis(n=27), alcoholic cirrhosis(n=5) and end-stage liver disease(n=13). All of the liver tissues were from the Oriental Liver Transplant Center, Beijing,China. The expressions of Nrf2 and Nrf2-related genes, including its negative regulator Kelch-like ECH-associated protein 1(KEAP1), its targeted gene NAD(P)H-quinone oxidoreductase 1(NQO1), glutamate-cysteine ligase catalytic subunit(GCLC) and modified subunit(GCLM), heme oxygenase 1(HO-1) and peroxiredoxin-1(PRDX1) were evaluated. RESULTS: The expression of Nrf2 was decreased in HCC, increased in alcoholic cirrhosis and end-stage liver disease. The expression of KEAP1 was increased in all of the liver samples.The most notable finding was the increased expression of NQO1 in HCC(18-fold), alcoholic cirrhosis(6-fold), endstage liver disease(5-fold) and HBV-related cirrhosis(3-fold).Peri-HCC also had 4-fold higher NQO1 m RNA as compared to the normal livers. GCLC m RNA levels were lower only in HCC, as compared to the normal livers and peri-HCC tissues.GCLM m RNA levels were higher in HBV-related cirrhosis and end-stage liver disease. HO-1 m RNA levels were increased in all liver tissues except for HCC. Peri-HCC had higher PRDX1 m RNA levels compared with HCC and normal livers.CONCLUSION: Nrf2 and Nrf2-related genes are aberrantly expressed in the liver in different diseases and the increase of NQO1 was the most notable finding, especially in HCC. 展开更多
关键词 Nrf2-related gene expression cirrhosis hepatocellular carcinoma end-stage liver disease
暂未订购
Expression of mature peptide of human bone morphogenetic protein-2 in Escherichia coli 被引量:1
17
作者 蒲勤 陈苏民 陈南春 《Journal of Medical Colleges of PLA(China)》 CAS 1998年第1期40-42,共3页
To express die mature peptide of human bone morphogenetic protein-2 in Escherichia coil. Methods: TheDNA fragment encoding the mature peptide of human bone morphogenetic protein-2 (hBMP-2m) was inserted into expressio... To express die mature peptide of human bone morphogenetic protein-2 in Escherichia coil. Methods: TheDNA fragment encoding the mature peptide of human bone morphogenetic protein-2 (hBMP-2m) was inserted into expression vectorpDH in which foreign gene was controlled by PRPL promoters. E. coli DH5a transformed with recombinant plasmid pDHB2m wasinduced at 42℃to express the target protein. The expressed product was partially purified and refolded, and then implanted intorat thigh muscles to assay its bone inductive activity. Results: After induction, a protein band on SDS-PAGE gel with an apparentmol. wt. of 13kD was observed to anticipate in the strain carrying pDHB2m, but not in the control. The expressed hBMP-2m accounted for 45%-60% of the total bacterial protein. The expressed product existed in a form of inclusion body. After partially purified and refolded, rhBMP-2m could induce the formation of cartilage and bone tissue heterotopically. Conclusion: The maturepeptide of human bone morphogenetic protein-2 has ben successfully expressed in E. coli and the product has ectopic bone inductive activity. 展开更多
关键词 HUMAN BONE morphogenetic protein-2 RECOMBINANT DNA gene expression
暂未订购
Cloning and Expression Analysis of <i>RrGT2</i>Gene Related to Anthocyanin Biosynthesis in <i>Rosa rugosa</i> 被引量:2
18
作者 Xiaoming Sui Yang Wang +3 位作者 Mingyuan Zhao Xu Han Lanyong Zhao Zongda Xu 《American Journal of Plant Sciences》 2018年第10期2008-2019,共12页
At present, the research about flower color of Rosa rugosa is a very inno-vative and practical study. Glycosylation modification fulfills an important role in increasing the stability and solubility of anthocyanin in ... At present, the research about flower color of Rosa rugosa is a very inno-vative and practical study. Glycosylation modification fulfills an important role in increasing the stability and solubility of anthocyanin in plants. In this study, based on the transcriptional database of R. rugosa, a gene with full length cDNA of 1422bp, encoding 473 amino acids, designated as RrGT2, were isolated from flowers of R. rugosa ‘Zizhi’ and then functionally characterized. According to online software prediction, the molecular formula of the protein encoded by the RrGT2 gene is C2334H3628N602O711S18, the relative molecular mass is 52,075.17 Da, and the theoretical isoelectric point is pI = 4.76. The result of the RrGT2 protein 3D model construction showed that it had the highest homology with the UDP-glycosyltransferase 74F2 protein model in the database (39.53%). Sequence alignments with the NCBI database showed that the RrGT2 protein is a member of the GTB superfamily. Homology analysis revealed that the coding regions of RrGT2 was highly specific among different species, but still had typical conserved amino acid residues called PSPG that are crucial for RrGT2 enzyme activity. RrGT2 transcripts were detected in five flowering stages and seven tissues of R. rugosa ‘Zizhi’, R. rugosa ‘Fenzizhi’ and R. rugosa ‘Baizizhi’, and their expression patterns corresponded with the accumulation of antho-cyanins. Therefore, we speculated that glycosylation of RrGT2 plays a crucial role in anthocyanin biosynthesis in R. rugosa. 展开更多
关键词 Rosa RUGOSA RrGT2 gene CLONE gene expression ANTHOCYANIN
暂未订购
Effect of Dai-Saiko-To (Da-Chai-Hu-Tang) on LDL-Receptor Gene Expression in Human Hepatoma Cell Line (HepG2) 被引量:2
19
作者 Akira Iizuka Fumihiko Yoshie +5 位作者 Sakae Amagaya Takaaki Yasuda Maki Iizuka Haruyo Yamaguchi Seiji Nagumo Kazuo Kondo 《American Journal of Plant Sciences》 2013年第2期454-459,共6页
We previously reported that Dai-saiko-to (Da-Chai-Hu-Tang), a traditional Japanese kampo medicine, increased LDL receptor mRNA expression in the liver of the hypercholesterolemic rabbits. In this study, we focused on ... We previously reported that Dai-saiko-to (Da-Chai-Hu-Tang), a traditional Japanese kampo medicine, increased LDL receptor mRNA expression in the liver of the hypercholesterolemic rabbits. In this study, we focused on LDL receptor gene expression in a human hepatoma cell line (HepG2) treated with Dai-saiko-to extract and the extracts of eight herbs presented in Dai-saiko-to. Dai-saiko-to extract significantly increased LDL receptor gene and SREBP2 gene expression compared with the control. The extracts of four herbs, Bupleurum root, Pinellia tuber, Scutellaria root and Peony root significantly increased the LDL receptor gene expression. Whereas, Jujube, Immature orange, Ginger and Rhubarb extracts did not change the gene expression. These results suggest that Dai-saiko-to increased the expression of the cholesterol transport gene (LDL receptor) regulated by SREBP2 gene in the human hepatoma cell line. The pharmacological activity of Dai-saiko-to against hypercholesterolemia and atheromatous lesions related for these four herbal components. 展开更多
关键词 KAMPO Dai-Saiko-To LDL Receptor gene expression HEPG2
暂未订购
EHMT2 (G9a) activation in mantle cell lymphoma and its associated DNA methylation and gene expression 被引量:1
20
作者 Jun Wang Hui Xu +6 位作者 Shuang Ge Chaoshuai Xue Hailing Li Xiaotong Jing Ke Liang Xiaoying Zhang Cuijuan Zhang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第6期836-849,共14页
Objective:The function of euchromatic histone-lysine N-methyltransferase 2(EHMT2)has been studied in several cancers;however,little is known about its role in mantle cell lymphoma(MCL).Thus,this study aimed to charact... Objective:The function of euchromatic histone-lysine N-methyltransferase 2(EHMT2)has been studied in several cancers;however,little is known about its role in mantle cell lymphoma(MCL).Thus,this study aimed to characterize the significance and function of EHMT2 in MCL.Methods:EHMT2 expression in MCL and reactive hyperplasia(RH)were investigated by immunohistochemistry.Genome-wide analysis of DNA methylation was performed on EHMT2+MCL samples.The function of EHMT2 was determined by CCK&flow cytometry,and western blot assays.Gene expression profile analysis was performed before and after EHMT2 knockdown to search for EHMT2-regulated genes.Co-immunoprecipitation(Co-IP)experiments were conducted to identify the proteins interacting with EHMT2.Results:EHMT2 was expressed in 68.57%(24/35)of MCLs but not in any RHs.Genome-wide analysis of DNA methylation on EHMT2+MCLs revealed that multiple members of the HOX,FOX,PAX,SOX,and CDX families were hypermethylated or hypomethylated in EHMT2+MCLs.BIX0I294,a EHMT2 inhibitor,inhibited MCL cell growth and stalled cells in the G1 phase.Additionally,BIX01294 downregulated the expressions of cell cycle proteins,cyclin DI,CDK4,and P21,but upregulated the expressions of apoptosis-related proteins,Bax and caspase-3.Co-IP experiments revealed that EHMT2 interacted with UHRF1,HDAC1,and HDAC2 but not with HDCA3.After EHMT2 knockdown,multiple genes were regulated,including CD5 and CCND1,mostly enriched in the Tec kinase signaling pathway.In addition,several genes(e.g.,MARCH 1,CCDC50,HIP1,and WNT3)were aberrantly methylated in EHMT2+MCLs.Conclusions:For the first time,we determined the significance of EHMT2 in MCL and identified potential EHMT2-regulated genes. 展开更多
关键词 DNA methylation mantle cell lymphoma epigenetic biomarker EHMT2 gene expression
暂未订购
上一页 1 2 80 下一页 到第
使用帮助 返回顶部