The development of human endometrial carcinoma(HEC) is a complex pathologic process involves several oncogenes and tumor suppressor genes.The full-length paired-box gene 2(pax2),a recently discovered oncogene,promotes...The development of human endometrial carcinoma(HEC) is a complex pathologic process involves several oncogenes and tumor suppressor genes.The full-length paired-box gene 2(pax2),a recently discovered oncogene,promotes cell proliferation and growth and inhibits apoptosis of HEC cells.Here,we examined the effect of pax2 small interfering RNA(siRNA) on the growth of transplanted HEC cells in nude mice.The expression of Pax2 in 21 cases of normal endometrium and 38 cases of HEC was examined by immohistochemistry(IHC).HEC models were developed by subcutaneously transferring HEC cells into nude mice,followed by treatment with empty lentivirus vector,lentivirus vector-based pax2 siRNA,and phosphate buffered saline,respectively.Four weeks later,tumor size was measured,tumor inhibition rate was calculated,and histological analyses were conducted after staining with hematoxylin and eosin.The expression of Pax2 and Bcl-2 was detected by Western blot;proliferating cell nuclear antigen(PCNA) was detected by IHC.Significant differences were observed in the positive rate of Pax2 between normal endometrium and HEC(14.2% vs.60.5%,P<0.01).The expression index of Pax2 in well differentiated tumors was 1.88±1.68,much lower than that in tumors of moderate(3.07±1.96,P<0.05) or poor differentiation(5.45±2.76,P<0.01).Tumor necrosis increased,nuclear basophilia stain decreased,tumor growth was inhibited,and PCNA,Pax2,and Bcl-2 expression was reduced in HEC models treated with pax2 siRNA.These results indicate that Pax2 expression is related to HEC tumor biology with the increased expression of Pax2 correlated to malignancy.pax2 siRNA down-regulates Pax2 expression and inhibits tumorigenesis of HEC in nude mice,possibly due to cell apoptosis and the inhibition of tumor proliferation induced by down-regulation of Bcl-2.展开更多
Specific challenges arise in the task of real-time automatic data reduction of optical space debris observations. Here we present an automatic technique that optimally detects and measures the sources from images of o...Specific challenges arise in the task of real-time automatic data reduction of optical space debris observations. Here we present an automatic technique that optimally detects and measures the sources from images of optical space debris ob- servations. We show that highly reliable and accurate results can be obtained on most images produced by our specific sensors, and due to optimizations, the whole pipeline works fast and efficiently. Tests demonstrate that the technique performs better than SExtractor from the point of view of fast and accurate detection, therefore it is well suited for data reduction of optical space debris observations.展开更多
In order to implement an observing strategy, image degradation that occurs during optical observation of space debris is ineluctable and has distinct characteris- tics. Image restoration is presented as a way to remov...In order to implement an observing strategy, image degradation that occurs during optical observation of space debris is ineluctable and has distinct characteris- tics. Image restoration is presented as a way to remove the influence of degradation in CCD images of space debris, based on assumed PSF models with the same F-WHM as images of the object. In the process of image restoration, the maximum entropy method is adopted. The results of reduction using observed raw CCD images indi- cate that the precision in estimating positions of objects is improved and the effects of degradation are reduced. Improving the astrometry of space debris using image restoration is effective and feasible.展开更多
An optical survey is the main technique for detecting space debris. Due to the specific character- istics of observation, the pointing errors and tracking errors of the telescope as well as image degradation may be si...An optical survey is the main technique for detecting space debris. Due to the specific character- istics of observation, the pointing errors and tracking errors of the telescope as well as image degradation may be significant, which make it difficult for astrometric calibration. Here we present an improved method that corrects the pointing and tracking errors, and measures the image position precisely. The pipeline is tested on a number of CCD images obtained from a 1-m telescope administered by Xinjiang Astronomical Observatory while observing a GPS satellite. The results show that the position measurement error of the background stars is around 0.1 pixel, while the time cost for a single frame is about 7.5 s; hence the relia- bility and accuracy of our method are demonstrated. In addition, our method shows a versatile and feasible way to perform space debris observation utilizing non-dedicated telescopes, which means more sensors could be involved and the ability to perform surveys could be improved.展开更多
文摘The development of human endometrial carcinoma(HEC) is a complex pathologic process involves several oncogenes and tumor suppressor genes.The full-length paired-box gene 2(pax2),a recently discovered oncogene,promotes cell proliferation and growth and inhibits apoptosis of HEC cells.Here,we examined the effect of pax2 small interfering RNA(siRNA) on the growth of transplanted HEC cells in nude mice.The expression of Pax2 in 21 cases of normal endometrium and 38 cases of HEC was examined by immohistochemistry(IHC).HEC models were developed by subcutaneously transferring HEC cells into nude mice,followed by treatment with empty lentivirus vector,lentivirus vector-based pax2 siRNA,and phosphate buffered saline,respectively.Four weeks later,tumor size was measured,tumor inhibition rate was calculated,and histological analyses were conducted after staining with hematoxylin and eosin.The expression of Pax2 and Bcl-2 was detected by Western blot;proliferating cell nuclear antigen(PCNA) was detected by IHC.Significant differences were observed in the positive rate of Pax2 between normal endometrium and HEC(14.2% vs.60.5%,P<0.01).The expression index of Pax2 in well differentiated tumors was 1.88±1.68,much lower than that in tumors of moderate(3.07±1.96,P<0.05) or poor differentiation(5.45±2.76,P<0.01).Tumor necrosis increased,nuclear basophilia stain decreased,tumor growth was inhibited,and PCNA,Pax2,and Bcl-2 expression was reduced in HEC models treated with pax2 siRNA.These results indicate that Pax2 expression is related to HEC tumor biology with the increased expression of Pax2 correlated to malignancy.pax2 siRNA down-regulates Pax2 expression and inhibits tumorigenesis of HEC in nude mice,possibly due to cell apoptosis and the inhibition of tumor proliferation induced by down-regulation of Bcl-2.
基金funded by the National Natural Science Foundation of China(Grant Nos.11125315 and 11033009)
文摘Specific challenges arise in the task of real-time automatic data reduction of optical space debris observations. Here we present an automatic technique that optimally detects and measures the sources from images of optical space debris ob- servations. We show that highly reliable and accurate results can be obtained on most images produced by our specific sensors, and due to optimizations, the whole pipeline works fast and efficiently. Tests demonstrate that the technique performs better than SExtractor from the point of view of fast and accurate detection, therefore it is well suited for data reduction of optical space debris observations.
基金funded by the National Natural Science Foundation of China (Grant Nos.11125315 and 11033009)
文摘In order to implement an observing strategy, image degradation that occurs during optical observation of space debris is ineluctable and has distinct characteris- tics. Image restoration is presented as a way to remove the influence of degradation in CCD images of space debris, based on assumed PSF models with the same F-WHM as images of the object. In the process of image restoration, the maximum entropy method is adopted. The results of reduction using observed raw CCD images indi- cate that the precision in estimating positions of objects is improved and the effects of degradation are reduced. Improving the astrometry of space debris using image restoration is effective and feasible.
基金funded by the National Natural Science Foundation of China(Grant Nos.11125315,11403108 and 11273069)the Youth Innovation Promotion Association of CAS(2015252)
文摘An optical survey is the main technique for detecting space debris. Due to the specific character- istics of observation, the pointing errors and tracking errors of the telescope as well as image degradation may be significant, which make it difficult for astrometric calibration. Here we present an improved method that corrects the pointing and tracking errors, and measures the image position precisely. The pipeline is tested on a number of CCD images obtained from a 1-m telescope administered by Xinjiang Astronomical Observatory while observing a GPS satellite. The results show that the position measurement error of the background stars is around 0.1 pixel, while the time cost for a single frame is about 7.5 s; hence the relia- bility and accuracy of our method are demonstrated. In addition, our method shows a versatile and feasible way to perform space debris observation utilizing non-dedicated telescopes, which means more sensors could be involved and the ability to perform surveys could be improved.
