Objective: To investigate the effects of GM1 on inducing adult rat bone marrow stromal cells(MSCs) to form neural progenitor cells and their differentiation. Methods: Purified MSCs were induced by different components...Objective: To investigate the effects of GM1 on inducing adult rat bone marrow stromal cells(MSCs) to form neural progenitor cells and their differentiation. Methods: Purified MSCs were induced by different components of basic fibroblast growth factor (bFGF) alone, GM1 alone or combination of bFGF with GM1. After 3 days’ incubation, fibronectin and collagen I were detected with immunocytochemistry, and nestin was detected with immunofluorescence. Neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and galactose cerebroside (GalC) were detected with immunocytochemistry after 7 days’ incubation. Results: After induction with bFGF alone or combination of bFGF and GM1, some MSCs exhibited the phenotypes of neural progenitor cells, and then neurons and astrocytes. In these two groups, the positive cells for fibronectin and collagen I decreased markedly after 3 days’ induction. At the same time, the positive cells for nestin increased markedly. After 7 days’ induction, NSE and GFAP positive cells increased significantly. Furthermore, the addition of bFGF and GM1 caused the maximal variation. However, addition of GM1 alone had no inductive effects. Conclusions: Combination of bFGF with GM1 may synergistically promote the transformation of MSCs and differentiation into neurons and astrocyte like cells. The results suggest a promising route for the application of MSCs.展开更多
AIM: To explore different roles of TGF-β (transforming growth factor beta) and bone morphogenetic proteins (BMPs)in hepatic stellate cell proliferation and trans-differentiation.METHODS: Hepatic stellate cells were i...AIM: To explore different roles of TGF-β (transforming growth factor beta) and bone morphogenetic proteins (BMPs)in hepatic stellate cell proliferation and trans-differentiation.METHODS: Hepatic stellate cells were isolated from male Sprague-Dawley rats. Sub-cultured hepatic stellate cells were employed for cell proliferation assay with WST-1 reagent and Western blot analysis with antibody against smooth muscle alpha actin (SMA).RESULTS: The results indicated that TGF-β1 significantly inhibited cell proliferation at concentration as low as 0.1 ng/ml, but both BMP-2 and BMP-4 did not affect cell proliferation at concentration as high as 10 ng/ml. The effect on hepatic stellate cell trans-differentiation was similar between TGFβ1 and BMPs. However, BMPs was more potent at transdifferentiation of hepatic stellate cells than TGF-β1. In addition, we observed that TGF-β1 transient reduced the abundance of SMA in hepatic stellate cells.CONCLUSION: TGF-β may be more important in regulation of hepatic stellate cell proliferation while BMPs may be the major cytokines regulating hepatic stellate cell transdifferentiation.展开更多
AIM: To study the effect of hepatitis C virus nonstructural protein 3 c-terminal deleted protein (HCV NS3-5') on hepatocyte transformation and tumor development.METHODS: QSG7701 cells were transfected with plasmid...AIM: To study the effect of hepatitis C virus nonstructural protein 3 c-terminal deleted protein (HCV NS3-5') on hepatocyte transformation and tumor development.METHODS: QSG7701 cells were transfected with plasmid pRcHCNS3-5' (expressing HCV NS3 c-terminal deleted protein) by lipofectamine and selected in G418. The expression of HCV NS3 gene and protein was determined by PCR and immunohistochemistry respectively. Biological behavior of transfected cells was observed through cell proliferation assay, anchorage-independent growth and tumor development in nude mice. The expression of HCV NS3 and c-mycproteins in the induced tumor was evaluated by immunohistochemistry.RESULTS: HCV NS3 was strongly expressed in QSG7701 cells transfected with plasmid pRcHCNS3-5' and the positive signal was located in cytoplasm. Cell proliferation assay showed that the population doubling time in pRcHCNS3-5' transfected cells was much shorter than that in pRcCMV and nontransfected cells (24 h, 26 h, 28 h respectively). The cloning ratio of cells transfected with pRcHCNS3-5; pRcCMV and nontransfected cells was 33 %, 1.46 %, 1.11%, respectively,the former one was higher than that in the rest two groups (P＜0.01). Tumor development was seen in nude mice inoculated with pRcHCNS3-5' transfected cells after 15 days.HE staining showed its feature of hepatocarcinoma, and immunohistochemistry confirmed the expressions of HCV NS3and c-mycproteins in tumor tissue. The positive control group inoculated with HepG2 also showed tumor development, while no tumor developed in the nude mice injected with pRcCMV and non-transfected cells after 40 days.CONCLUSION: 1.HCV NS3 c-terminal deleted protein has transforming and oncogenic potential. 2. Human liver cell line QSG7701 may be used as a good model to study HCV NS3 pathogenesis.展开更多
【动态】大多数罹患致心律失常性右心室心肌病（arrhythmogenic right ventricular dysplasia/eardiomyopathy,ARVD／C）这一遗传性心脏病的患者，都是在20岁左右时才出现症状。该病由于在年龄较小时缺乏症状使研究人员极难研究其发病...【动态】大多数罹患致心律失常性右心室心肌病（arrhythmogenic right ventricular dysplasia/eardiomyopathy,ARVD／C）这一遗传性心脏病的患者，都是在20岁左右时才出现症状。该病由于在年龄较小时缺乏症状使研究人员极难研究其发病机制和治疗手段。展开更多
Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour met...Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.展开更多
文摘Objective: To investigate the effects of GM1 on inducing adult rat bone marrow stromal cells(MSCs) to form neural progenitor cells and their differentiation. Methods: Purified MSCs were induced by different components of basic fibroblast growth factor (bFGF) alone, GM1 alone or combination of bFGF with GM1. After 3 days’ incubation, fibronectin and collagen I were detected with immunocytochemistry, and nestin was detected with immunofluorescence. Neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and galactose cerebroside (GalC) were detected with immunocytochemistry after 7 days’ incubation. Results: After induction with bFGF alone or combination of bFGF and GM1, some MSCs exhibited the phenotypes of neural progenitor cells, and then neurons and astrocytes. In these two groups, the positive cells for fibronectin and collagen I decreased markedly after 3 days’ induction. At the same time, the positive cells for nestin increased markedly. After 7 days’ induction, NSE and GFAP positive cells increased significantly. Furthermore, the addition of bFGF and GM1 caused the maximal variation. However, addition of GM1 alone had no inductive effects. Conclusions: Combination of bFGF with GM1 may synergistically promote the transformation of MSCs and differentiation into neurons and astrocyte like cells. The results suggest a promising route for the application of MSCs.
文摘AIM: To explore different roles of TGF-β (transforming growth factor beta) and bone morphogenetic proteins (BMPs)in hepatic stellate cell proliferation and trans-differentiation.METHODS: Hepatic stellate cells were isolated from male Sprague-Dawley rats. Sub-cultured hepatic stellate cells were employed for cell proliferation assay with WST-1 reagent and Western blot analysis with antibody against smooth muscle alpha actin (SMA).RESULTS: The results indicated that TGF-β1 significantly inhibited cell proliferation at concentration as low as 0.1 ng/ml, but both BMP-2 and BMP-4 did not affect cell proliferation at concentration as high as 10 ng/ml. The effect on hepatic stellate cell trans-differentiation was similar between TGFβ1 and BMPs. However, BMPs was more potent at transdifferentiation of hepatic stellate cells than TGF-β1. In addition, we observed that TGF-β1 transient reduced the abundance of SMA in hepatic stellate cells.CONCLUSION: TGF-β may be more important in regulation of hepatic stellate cell proliferation while BMPs may be the major cytokines regulating hepatic stellate cell transdifferentiation.
基金the Health Ministry Science Foundation of China,No.98-1-110
文摘AIM: To study the effect of hepatitis C virus nonstructural protein 3 c-terminal deleted protein (HCV NS3-5') on hepatocyte transformation and tumor development.METHODS: QSG7701 cells were transfected with plasmid pRcHCNS3-5' (expressing HCV NS3 c-terminal deleted protein) by lipofectamine and selected in G418. The expression of HCV NS3 gene and protein was determined by PCR and immunohistochemistry respectively. Biological behavior of transfected cells was observed through cell proliferation assay, anchorage-independent growth and tumor development in nude mice. The expression of HCV NS3 and c-mycproteins in the induced tumor was evaluated by immunohistochemistry.RESULTS: HCV NS3 was strongly expressed in QSG7701 cells transfected with plasmid pRcHCNS3-5' and the positive signal was located in cytoplasm. Cell proliferation assay showed that the population doubling time in pRcHCNS3-5' transfected cells was much shorter than that in pRcCMV and nontransfected cells (24 h, 26 h, 28 h respectively). The cloning ratio of cells transfected with pRcHCNS3-5; pRcCMV and nontransfected cells was 33 %, 1.46 %, 1.11%, respectively,the former one was higher than that in the rest two groups (P＜0.01). Tumor development was seen in nude mice inoculated with pRcHCNS3-5' transfected cells after 15 days.HE staining showed its feature of hepatocarcinoma, and immunohistochemistry confirmed the expressions of HCV NS3and c-mycproteins in tumor tissue. The positive control group inoculated with HepG2 also showed tumor development, while no tumor developed in the nude mice injected with pRcCMV and non-transfected cells after 40 days.CONCLUSION: 1.HCV NS3 c-terminal deleted protein has transforming and oncogenic potential. 2. Human liver cell line QSG7701 may be used as a good model to study HCV NS3 pathogenesis.
文摘Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.
