背景和目的:2016年美国国家癌症研究所(National Cancer Institute,NCI)宣布不再使用NCI-60细胞系进行药物筛选,提示传统的肿瘤细胞系失去作为药物研发和基础研究工具的价值。NCI-60细胞“退休”原因是基于癌症细胞系和动物的实验结果...背景和目的:2016年美国国家癌症研究所(National Cancer Institute,NCI)宣布不再使用NCI-60细胞系进行药物筛选,提示传统的肿瘤细胞系失去作为药物研发和基础研究工具的价值。NCI-60细胞“退休”原因是基于癌症细胞系和动物的实验结果没有在临床试验中获得对应的预期,导致绝大部分潜在药物临床试验失败。癌症细胞系失去价值归因于肿瘤细胞经过长期培养后,其增殖和转移等主要生物学行为和与之有关的关键蛋白质系统发生了根本改变,已不能代表患者的真实癌症特征。现阶段需要创立一种来源于患者新鲜癌症组织和具有清晰临床背景的新癌症模型。本研究旨在为药物研发和基础研究建立经济的患者来源的可以无限传代的乳腺癌原代细胞系。方法:乳腺癌组织在贵州医科大学附属医院乳腺外科收集。肿瘤组织样本收集得到贵州医科大学附属医院伦理委员会批准(伦理编号:2022伦理第313号),收集和使用肿瘤组织均遵守赫尔辛基宣言,患者的乳腺癌组织消化分离后在BCMI培养基中培养,待乳腺癌细胞增殖到一定数量时更换成DMEM培养基。乳腺癌细胞经短串联重复序列(short tandem repeat,STR)检测确定细胞特异性遗传学标志和来源。克隆形成实验和动物实验分析乳腺癌原代细胞系形成肿瘤的能力。结果:成功建立了6种乳腺癌原代细胞系。他们具有清晰的临床病理学特征,包括病理学标志性分子检测、临床诊断、治疗方案和结果以及确定的预后结果。STR检测确定了6种乳腺癌原代细胞系特异性遗传标志和确定了该细胞系的来源。克隆形成实验和动物移植实验说明乳腺癌原代细胞系增殖能力显著大于传统乳腺癌细胞系,二者在形成肿瘤能力方面存在明显的差异。结论:构建的6种乳腺癌原代细胞系为乳腺癌药物研发和基础研究提供了新的癌症模型。展开更多
The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Fo...The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Four blowing conditions are considered in the computer runs: top blowing, combined blowing using just a bottom centered nozzle, combined blowing using two bottom lateral nozzles, and full combined blowing using the three top and the three bottom nozzles. Computer simulations show that full combined blowing provides greater slag splashing than conventional top blowing.展开更多
Combining the system of rapid collection of ambient particles and ion chromatography, the system of rapid collection of fine particles and ion chromatography (RCFP-IC) was established to automatically analyze on-lin...Combining the system of rapid collection of ambient particles and ion chromatography, the system of rapid collection of fine particles and ion chromatography (RCFP-IC) was established to automatically analyze on-line the concentrations of water-soluble ions in ambient particles. Here, the general scheme of RCFP-IC is described and its basic performance is tested. The detection limit of RCFP-IC for SO4^2-, NO3^-, NO2^-, Cl^- and F- is below 0.3μg m^-3. The collection efficiency of RCFP-IC increases rapidly with increasing sized particles. For particles larger than 300 nm, the collection efficiency approaches 100%. The precision of RCFP-IC is more than 90% over 28 repetitions. The response of RCFP-IC is very sensitive and no obvious cross-pollution is found during measurement. A comparison of RCFP-IC with an integrated filter measurement indicates that the measurement of RCFP-IC is comparable in both laboratory experiments and field observations. The results of the field experiment prove that RCFP-IC is an effective on-line monitoring system and is helpful in source apportionment and pollution episode monitoring.展开更多
BACKGROUND: Human gliomas are more likely to express basic fibroblast growth factor-2 (FGF-2) insulin-like growth factor-1(IGF-1), and IGF-1 receptor (IGF-1R) than normal brain tissue. These factors activate si...BACKGROUND: Human gliomas are more likely to express basic fibroblast growth factor-2 (FGF-2) insulin-like growth factor-1(IGF-1), and IGF-1 receptor (IGF-1R) than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE: To utilize RNA interference (RNAi) technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING: This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS: Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA (siRNA) was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS: C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up: A (2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm) and B (siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES: mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS: All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively (P 〈 0.01). Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION: siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.展开更多
文摘背景和目的:2016年美国国家癌症研究所(National Cancer Institute,NCI)宣布不再使用NCI-60细胞系进行药物筛选,提示传统的肿瘤细胞系失去作为药物研发和基础研究工具的价值。NCI-60细胞“退休”原因是基于癌症细胞系和动物的实验结果没有在临床试验中获得对应的预期,导致绝大部分潜在药物临床试验失败。癌症细胞系失去价值归因于肿瘤细胞经过长期培养后,其增殖和转移等主要生物学行为和与之有关的关键蛋白质系统发生了根本改变,已不能代表患者的真实癌症特征。现阶段需要创立一种来源于患者新鲜癌症组织和具有清晰临床背景的新癌症模型。本研究旨在为药物研发和基础研究建立经济的患者来源的可以无限传代的乳腺癌原代细胞系。方法:乳腺癌组织在贵州医科大学附属医院乳腺外科收集。肿瘤组织样本收集得到贵州医科大学附属医院伦理委员会批准(伦理编号:2022伦理第313号),收集和使用肿瘤组织均遵守赫尔辛基宣言,患者的乳腺癌组织消化分离后在BCMI培养基中培养,待乳腺癌细胞增殖到一定数量时更换成DMEM培养基。乳腺癌细胞经短串联重复序列(short tandem repeat,STR)检测确定细胞特异性遗传学标志和来源。克隆形成实验和动物实验分析乳腺癌原代细胞系形成肿瘤的能力。结果:成功建立了6种乳腺癌原代细胞系。他们具有清晰的临床病理学特征,包括病理学标志性分子检测、临床诊断、治疗方案和结果以及确定的预后结果。STR检测确定了6种乳腺癌原代细胞系特异性遗传标志和确定了该细胞系的来源。克隆形成实验和动物移植实验说明乳腺癌原代细胞系增殖能力显著大于传统乳腺癌细胞系,二者在形成肿瘤能力方面存在明显的差异。结论:构建的6种乳腺癌原代细胞系为乳腺癌药物研发和基础研究提供了新的癌症模型。
文摘The influence of three different blowing conditions on the slag splashing process in a basic oxygen furnace for steelmaking is analyzed here using two-dimensional transient Computational Fluid Dynamics simulations. Four blowing conditions are considered in the computer runs: top blowing, combined blowing using just a bottom centered nozzle, combined blowing using two bottom lateral nozzles, and full combined blowing using the three top and the three bottom nozzles. Computer simulations show that full combined blowing provides greater slag splashing than conventional top blowing.
基金This work was supported by the National Natural Science Foundation of China under Grant No. 40525016.
文摘Combining the system of rapid collection of ambient particles and ion chromatography, the system of rapid collection of fine particles and ion chromatography (RCFP-IC) was established to automatically analyze on-line the concentrations of water-soluble ions in ambient particles. Here, the general scheme of RCFP-IC is described and its basic performance is tested. The detection limit of RCFP-IC for SO4^2-, NO3^-, NO2^-, Cl^- and F- is below 0.3μg m^-3. The collection efficiency of RCFP-IC increases rapidly with increasing sized particles. For particles larger than 300 nm, the collection efficiency approaches 100%. The precision of RCFP-IC is more than 90% over 28 repetitions. The response of RCFP-IC is very sensitive and no obvious cross-pollution is found during measurement. A comparison of RCFP-IC with an integrated filter measurement indicates that the measurement of RCFP-IC is comparable in both laboratory experiments and field observations. The results of the field experiment prove that RCFP-IC is an effective on-line monitoring system and is helpful in source apportionment and pollution episode monitoring.
基金the National Natural Science Foundation of China,No.30371459Science and Technology Development Fund of Shanghai,No.034047
文摘BACKGROUND: Human gliomas are more likely to express basic fibroblast growth factor-2 (FGF-2) insulin-like growth factor-1(IGF-1), and IGF-1 receptor (IGF-1R) than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE: To utilize RNA interference (RNAi) technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING: This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS: Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA (siRNA) was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS: C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up: A (2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm) and B (siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES: mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS: All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively (P 〈 0.01). Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION: siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.