AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological character...AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine sple展开更多
Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sin...Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sinensis ) that were treated with 0.25 mmol/L iodoacetic acid for 15 min. It took nearly 15 months for the fusion_derived calli to develop into embryoids that were only originated in the medium of MT supplemented with 2% glycerol. The shoots were recalcitrant to rooting in the root_induction medium. In vitro grafting was employed to produce whole plants though one self_rooting plant was obtained. Cytological determination of root and shoot tips showed mainly diploid and aneuploid cells, together with few tetraploid cells in some plants. RAPD (random amplified polymorphism DNA) analysis with 10_mer primers demonstrated that bands specific to the fusion parents were detected in the regenerated plants, indicating that interspecific somatic hybrids have been obtained via protoplast asymmetric fusion in Citrus .展开更多
AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations...AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations, cell fusion and limit dilution, 8 Ag resistant cells were selected, and HGPRT - Hca P cells and eight cloned hybridoma cells were obtained. To observe their metastatic ability, they were inoculated into mice foodtaps and the drainage lymph nodes were examined under microscope. RESULTS The end concentration of 8 Ag which was used to select HGPRT deficient Hca P cells was 30mg/L . All the cells selected died in HAT culture medium in one week. Fused cells appeared approximately 9 days later. They were round, transparent and a little larger than their parental cells. Eight clones of hybridoma cells were obtained and named as PSH1 PSH8. The metastatic rate of HGPRT - Hca P cells and PSH7 cells was 28 6% and 71 4% respectively, the difference being significant ( P <0 05). The metastatic rate of other clones was no more than 20% and there was no significant difference from HGPRT - Hca P cells ( P >0 05). CONCLUSION In normal mice splenic lymphocytes, there are some factors that could inhibit tumor metastasis, however, there are some other factors accelerating tumor cells to metastasize. The establishment of PSH7 provides an experimental model which could be used to study the factors involved in metastasis.展开更多
Aim： To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells. Methods： The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to ...Aim： To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells. Methods： The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to pDsRed- Express-N 1 and transfected back into TM3 mouse Leydig cells for Cox7a2 overexpression by transient gene transfection. Steroidogenesis affected by overexpressed Cox7a2 was studied by ELISA. To elicit the mechanism of this effect, expression of steroidogenic acute regulatory （STAR） protein and reactive oxygen species （ROS） were examined by Western blot and fluorometer, respectively. Results： The cDNA of Cox7a2 （249 bp） was cloned from Leydig cells and confirmed by DNA sequencing. After constructed pDsRed-Express-N1-Cox7a2 was transfected back into TM3 mouse Leydig cells, Cox7a2 inhibited not only luteinizing hormone （LH）-induced secretion of testosterone but also the expression of StAR protein. At the same time, Cox7a2 increased the activity of ROS in TM3 mouse Leydig cells. Conclusion： Cox7a2 inhibited LH-induced StAR protein expression, and consequent testosterone production, at least in part, by increasing ROS activity in TM3 mouse Leydig cells.展开更多
针对图像拼接过程中传统算法存在特征点匹配正确率低和图像融合过程中出现重影、色差及拼接缝隙等问题,提出一种融合改进SURF(Speeded Up Robust Feature)和Cell加速的幂函数加权图像拼接方法。首先利用余弦相似度初步判断特征点的相似...针对图像拼接过程中传统算法存在特征点匹配正确率低和图像融合过程中出现重影、色差及拼接缝隙等问题,提出一种融合改进SURF(Speeded Up Robust Feature)和Cell加速的幂函数加权图像拼接方法。首先利用余弦相似度初步判断特征点的相似性,然后结合双向一致性算法和MSAC算法对粗匹配点进行精匹配,最后使用Cell加速的幂函数权重对图像进行融合,从而完成图像拼接。实验结果表明,相比于其他算法,所提算法的特征点匹配正确率高出约为11个百分点,均方误差缩小约为1.32%~1.48%,信息熵提升约为0.98%~1.70%,拼接总时间消耗减少约为2 s。所提算法在匹配正确率和融合效果上有较好的效果,且同时拥有较好的拼接图像质量,具有更好的普适性。展开更多
基金Supported jby the Natural Science Foundation of Guangdong Province China,No.980180
文摘AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine sple
基金TheNational Natural Science Foundation of China(3983026039625017)the International Foundation for Science(D/3001_1)
文摘Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sinensis ) that were treated with 0.25 mmol/L iodoacetic acid for 15 min. It took nearly 15 months for the fusion_derived calli to develop into embryoids that were only originated in the medium of MT supplemented with 2% glycerol. The shoots were recalcitrant to rooting in the root_induction medium. In vitro grafting was employed to produce whole plants though one self_rooting plant was obtained. Cytological determination of root and shoot tips showed mainly diploid and aneuploid cells, together with few tetraploid cells in some plants. RAPD (random amplified polymorphism DNA) analysis with 10_mer primers demonstrated that bands specific to the fusion parents were detected in the regenerated plants, indicating that interspecific somatic hybrids have been obtained via protoplast asymmetric fusion in Citrus .
文摘AIM To study the effect of cell fusion on metastatic ability of mouse hepatocarcinoma cells and the factors involved in the process of metastasis. METHODS By the method of successively increasing the concentrations, cell fusion and limit dilution, 8 Ag resistant cells were selected, and HGPRT - Hca P cells and eight cloned hybridoma cells were obtained. To observe their metastatic ability, they were inoculated into mice foodtaps and the drainage lymph nodes were examined under microscope. RESULTS The end concentration of 8 Ag which was used to select HGPRT deficient Hca P cells was 30mg/L . All the cells selected died in HAT culture medium in one week. Fused cells appeared approximately 9 days later. They were round, transparent and a little larger than their parental cells. Eight clones of hybridoma cells were obtained and named as PSH1 PSH8. The metastatic rate of HGPRT - Hca P cells and PSH7 cells was 28 6% and 71 4% respectively, the difference being significant ( P <0 05). The metastatic rate of other clones was no more than 20% and there was no significant difference from HGPRT - Hca P cells ( P >0 05). CONCLUSION In normal mice splenic lymphocytes, there are some factors that could inhibit tumor metastasis, however, there are some other factors accelerating tumor cells to metastasize. The establishment of PSH7 provides an experimental model which could be used to study the factors involved in metastasis.
文摘Aim： To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells. Methods： The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to pDsRed- Express-N 1 and transfected back into TM3 mouse Leydig cells for Cox7a2 overexpression by transient gene transfection. Steroidogenesis affected by overexpressed Cox7a2 was studied by ELISA. To elicit the mechanism of this effect, expression of steroidogenic acute regulatory （STAR） protein and reactive oxygen species （ROS） were examined by Western blot and fluorometer, respectively. Results： The cDNA of Cox7a2 （249 bp） was cloned from Leydig cells and confirmed by DNA sequencing. After constructed pDsRed-Express-N1-Cox7a2 was transfected back into TM3 mouse Leydig cells, Cox7a2 inhibited not only luteinizing hormone （LH）-induced secretion of testosterone but also the expression of StAR protein. At the same time, Cox7a2 increased the activity of ROS in TM3 mouse Leydig cells. Conclusion： Cox7a2 inhibited LH-induced StAR protein expression, and consequent testosterone production, at least in part, by increasing ROS activity in TM3 mouse Leydig cells.
文摘针对图像拼接过程中传统算法存在特征点匹配正确率低和图像融合过程中出现重影、色差及拼接缝隙等问题,提出一种融合改进SURF(Speeded Up Robust Feature)和Cell加速的幂函数加权图像拼接方法。首先利用余弦相似度初步判断特征点的相似性,然后结合双向一致性算法和MSAC算法对粗匹配点进行精匹配,最后使用Cell加速的幂函数权重对图像进行融合,从而完成图像拼接。实验结果表明,相比于其他算法,所提算法的特征点匹配正确率高出约为11个百分点,均方误差缩小约为1.32%~1.48%,信息熵提升约为0.98%~1.70%,拼接总时间消耗减少约为2 s。所提算法在匹配正确率和融合效果上有较好的效果,且同时拥有较好的拼接图像质量,具有更好的普适性。
