AIM:To investigate the biological features of hepatitis B virus(HBV)-transfected HepG2.2.15 cells. METHODS:The cell ultrastructure,cell cycle and apoptosis,and the abilities of proliferation and invasion of HBV-transf...AIM:To investigate the biological features of hepatitis B virus(HBV)-transfected HepG2.2.15 cells. METHODS:The cell ultrastructure,cell cycle and apoptosis,and the abilities of proliferation and invasion of HBV-transfected HepG2.2.15 and the parent HepG2 cells were examined by electron microscopy,flow cytometry, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trans-well assay.Oncogenicity of the two cell lines was compared via subcutaneous injection and orthotopic injection or implantation in nude mice,and the pathological analysis of tumor formation was performed.Two cytoskeletal proteins were detected by Western blotting. RESULTS:Compared with HepG2 cells,HepG2.2.15 cells showed organelle degeneration and filopodia disappearance under electron microscope.HepG2.2.15 cells proliferated and migrated slowly in vitro,and hardly formed tumor and lung metastasis in nude mice.Flow cytometry showed that the majority of HepG2.2.15 cells were arrested in G1 phase,and apoptosis was minor in both cell lines.Furthermore,the levels of cytoskeletal proteins F-actin and Ezrin were decreased in HepG2.2.15 cells. CONCLUSION:HepG2.2.15 cells demonstrated a lower proliferation and invasion ability than the HepG2 cells due to HBV transfection.展开更多
Background The induced pluripotent stem cell （iPSC） has shown great potential in cellular therapy of myocardial infarction （MI）, while its application is hampered by the low efficiency of cardiomyocyte differentia...Background The induced pluripotent stem cell （iPSC） has shown great potential in cellular therapy of myocardial infarction （MI）, while its application is hampered by the low efficiency of cardiomyocyte differentiation. The present study was designed to investigate the effects of cardiotrophin-1 （CT-1） on cardiomyocyte differentiation from mouse induced pluripotent stem cells （miPSCs） and the underlying mechanisms involved. Methods The optimal treatment condition for cardiomyocyte differentiation from miPSCs was established with ideal concentration （10 ng/mL） and duration （from day 3 to day 14） of CT-1 administration. Up-regulated expression of cardiac specific genes that accounted for embryonic cardiogenesis was observed by quantitative RT-PCR. Elevated amount of a-myosin heavy chain （ct-MHC） and cardiac troponin I （cTn I） positive cells were detected by immunofluorescence staining and flow cytometry analysis in CT- 1 group. Results Transmission electron microscopic analysis revealed that cells treated with CT- 1 showed better organized sacromeric structure and more mitochondria, which are morphological characteristic of matured cardiomyocytes. Western blot demonstrated that CT-1 promotes cardiomyocyte differentiation from miPSCs partly via JAK2/STAT3/Pim-1 pathway as compared with control group. Conclusions These findings suggested that CT-1 could enhance the cardiomyocyte differentiation as well as the maturation of mouse induced pluripotent stem cell derived cardiomyocytes by regulating JAK2/STAT3/Pim-1 signaling pathway.展开更多
We develop and assess a model of the turbulent burning velocity ST over a wide range of conditions.The aim is to obtain an explicit ST model for turbulent combustion modeling and flame analysis.The model consists of s...We develop and assess a model of the turbulent burning velocity ST over a wide range of conditions.The aim is to obtain an explicit ST model for turbulent combustion modeling and flame analysis.The model consists of sub models of the stretch factor and the turbulent flame area.The stretch factor characterizes the flame response of turbulence stretch and incorporates detailed chemistry and transport effects with a lookup table of laminar counterflow flames.The flame area model captures the area growth based on Lagrangian statistics of propagating surfaces and considers the effects of turbulence length scales and fuel characteristics.The present model predicts sT via an algebraic expression without free parameters.We assess the model using 490 cases of the direct numerical simulation or experiment reported from various research groups on planar and Bunsen flames over a wide range of conditions,covering fuels from hydrogen to n-dodecane,pressures from 1 to 30 atm,lean and rich mixtures,turbulence intensity ratios from 0.1 to 177.6,and turbulence length ratios from 0.5 to 66.7.Despite the scattering sT data in the literature,the comprehensive comparison shows that the proposed ST model has an overall good agreement over the wide range of conditions,with the averaged modeling error of 28.1%.展开更多
基金Supported by Graduate Innovation Foundation of Harbin Medical University No.HCXB2010010Key Technology Project of Heilongjiang Science and Technology Department,No.ZJY04-0102
文摘AIM:To investigate the biological features of hepatitis B virus(HBV)-transfected HepG2.2.15 cells. METHODS:The cell ultrastructure,cell cycle and apoptosis,and the abilities of proliferation and invasion of HBV-transfected HepG2.2.15 and the parent HepG2 cells were examined by electron microscopy,flow cytometry, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trans-well assay.Oncogenicity of the two cell lines was compared via subcutaneous injection and orthotopic injection or implantation in nude mice,and the pathological analysis of tumor formation was performed.Two cytoskeletal proteins were detected by Western blotting. RESULTS:Compared with HepG2 cells,HepG2.2.15 cells showed organelle degeneration and filopodia disappearance under electron microscope.HepG2.2.15 cells proliferated and migrated slowly in vitro,and hardly formed tumor and lung metastasis in nude mice.Flow cytometry showed that the majority of HepG2.2.15 cells were arrested in G1 phase,and apoptosis was minor in both cell lines.Furthermore,the levels of cytoskeletal proteins F-actin and Ezrin were decreased in HepG2.2.15 cells. CONCLUSION:HepG2.2.15 cells demonstrated a lower proliferation and invasion ability than the HepG2 cells due to HBV transfection.
基金This work was supported by the National Funds for Distinguished Young Scientists of China （No. 81325009） and National Nature Science Foundation of China （No. 81270168, No. 81227901）, （Feng Cao BWS12J037）, Innovation Team granted by Ministry of Education PRC （IRT1053）, National Basic Research Program of China （2012CB518101）. Shaanxi Province Program （2013K12-02-03, 2014KCT-20）. The authors declare no conflict of interest.
文摘Background The induced pluripotent stem cell （iPSC） has shown great potential in cellular therapy of myocardial infarction （MI）, while its application is hampered by the low efficiency of cardiomyocyte differentiation. The present study was designed to investigate the effects of cardiotrophin-1 （CT-1） on cardiomyocyte differentiation from mouse induced pluripotent stem cells （miPSCs） and the underlying mechanisms involved. Methods The optimal treatment condition for cardiomyocyte differentiation from miPSCs was established with ideal concentration （10 ng/mL） and duration （from day 3 to day 14） of CT-1 administration. Up-regulated expression of cardiac specific genes that accounted for embryonic cardiogenesis was observed by quantitative RT-PCR. Elevated amount of a-myosin heavy chain （ct-MHC） and cardiac troponin I （cTn I） positive cells were detected by immunofluorescence staining and flow cytometry analysis in CT- 1 group. Results Transmission electron microscopic analysis revealed that cells treated with CT- 1 showed better organized sacromeric structure and more mitochondria, which are morphological characteristic of matured cardiomyocytes. Western blot demonstrated that CT-1 promotes cardiomyocyte differentiation from miPSCs partly via JAK2/STAT3/Pim-1 pathway as compared with control group. Conclusions These findings suggested that CT-1 could enhance the cardiomyocyte differentiation as well as the maturation of mouse induced pluripotent stem cell derived cardiomyocytes by regulating JAK2/STAT3/Pim-1 signaling pathway.
基金supported by the National Natural Science Foundation of China(Grant Nos.91841302,11925201,and 11988102)the National Key Research and Development.Program of China(Grant No.2020YFE0204200)。
文摘We develop and assess a model of the turbulent burning velocity ST over a wide range of conditions.The aim is to obtain an explicit ST model for turbulent combustion modeling and flame analysis.The model consists of sub models of the stretch factor and the turbulent flame area.The stretch factor characterizes the flame response of turbulence stretch and incorporates detailed chemistry and transport effects with a lookup table of laminar counterflow flames.The flame area model captures the area growth based on Lagrangian statistics of propagating surfaces and considers the effects of turbulence length scales and fuel characteristics.The present model predicts sT via an algebraic expression without free parameters.We assess the model using 490 cases of the direct numerical simulation or experiment reported from various research groups on planar and Bunsen flames over a wide range of conditions,covering fuels from hydrogen to n-dodecane,pressures from 1 to 30 atm,lean and rich mixtures,turbulence intensity ratios from 0.1 to 177.6,and turbulence length ratios from 0.5 to 66.7.Despite the scattering sT data in the literature,the comprehensive comparison shows that the proposed ST model has an overall good agreement over the wide range of conditions,with the averaged modeling error of 28.1%.
