Swine influenza A virus（swine IAV） circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 influenza pandemic. Among multiple subtypes/lineages of swine influenza A virus...Swine influenza A virus（swine IAV） circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 influenza pandemic. Among multiple subtypes/lineages of swine influenza A viruses, European avian-like（EA） H1N1 swine IAV has been dominant since 2005 in China and caused infections in humans in 2010. Highly sensitive and specific methods of detection are required to differentiate EA H1N1 swine IAVs from viruses belonging to other lineages and subtypes. In this study, a nested reverse transcription（RT）-PCR assay was developed to detect EA H1 swine IAVs. Two primer sets（outer and inner） were designed specifically to target the viral hemagglutinin genes. Specific PCR products were obtained from all tested EA H1N1 swine IAV isolates, but not from other lineages of H1 swine IAVs, other subtypes of swine IAVs, or other infectious swine viruses. The sensitivity of the nested RT-PCR was improved to 1 plaque forming unit（PFU） m L^（-1） which was over 10~4 PFU m L^（-1） for a previously established multiplex RT-PCR method. The nested RT-PCR results obtained from screening 365 clinical samples were consistent with those obtained using conventional virus isolation methods combined with sequencing. Thus, the nested RT-PCR assay reported herein is more sensitive and suitable for the diagnosis of clinical infections and surveillance of EA H1 swine IAVs in pigs and humans.展开更多
OBJECTIVES: To detect blood AFPmRNA in the nude mice bearing with human hepatocellular carcinoma (HCC) by using nested reverse transcriptase polymerase chain reaction (nested RT-PCR), and assess its significance in HC...OBJECTIVES: To detect blood AFPmRNA in the nude mice bearing with human hepatocellular carcinoma (HCC) by using nested reverse transcriptase polymerase chain reaction (nested RT-PCR), and assess its significance in HCC distant metastasis. METHOD: We detected 20 blood samples from the nude mice bearing with human HCC by nested RT-PCR to find out AFPmRNA. RESULT: AFPmRNA was detected in 6 blood samples from the nude mice hearing with human HCC (30. 0%), in which 4 mice developed distant metastasis. CONCLUSION: AFPmRNA may be used as an efficient and sensitive marker to detect blood spread of HCC cells. It can predict the occurrence of HCC distant metastasis.展开更多
Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution...Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution of CSFV in different organ samples showed some discrepancies in infected pigs. Four weaner pigs were inoculated with C-strain vaccine virus, then samples of spleen, tonsil, lung, mesenteric lymph node, kidney and brain were collected after slaughter and tested for E2 and NS5B genes using one-step RT-PCR and nested RT-PCR. Using the same method, 12 field cases were simultaneously studied. A discrepancy of CSFV in different samples was found upon detecting the target gene. The most reliable diagnostic organs were spleen and tonsil, and the nested RT-PCR assay provided a highly sensitive and specific method with comparable performance to the one-step RT-PCR assay.展开更多
Nested simulation encompasses the estimation of functionals linked to conditional expectations through simulation techniques.In this paper,we treat conditional expectation as a function of the multidimensional conditi...Nested simulation encompasses the estimation of functionals linked to conditional expectations through simulation techniques.In this paper,we treat conditional expectation as a function of the multidimensional conditioning variable and provide asymptotic analyses of general nonparametric least squared estimators on sieve,without imposing specific assumptions on the function’s form.Our study explores scenarios in which the convergence rate surpasses that of the standard Monte Carlo method and the one recently proposed based on kernel ridge regression.We use kernel ridge regression with inducing points and neural networks as examples to illustrate our theorems.Numerical experiments are conducted to support our statements.展开更多
Sparse array design has significant implications for improving the accuracy of direction of arrival(DOA)estimation of non-circular(NC)signals.We propose an extended nested array with a filled sensor(ENAFS)based on the...Sparse array design has significant implications for improving the accuracy of direction of arrival(DOA)estimation of non-circular(NC)signals.We propose an extended nested array with a filled sensor(ENAFS)based on the hole-filling strategy.Specifically,we first introduce the improved nested array(INA)and prove its properties.Subsequently,we extend the sum-difference coarray(SDCA)by adding an additional sensor to fill the holes.Thus the larger uniform degrees of freedom(uDOFs)and virtual array aperture(VAA)can be abtained,and the ENAFS is designed.Finally,the simulation results are given to verify the superiority of the proposed ENAFS in terms of DOF,mutual coupling and estimation performance.展开更多
基金supported by the National High-Tech R&D Program of China (2012AA101303)
文摘Swine influenza A virus（swine IAV） circulates worldwide in pigs and poses a serious public health threat, as evidenced by the 2009 H1N1 influenza pandemic. Among multiple subtypes/lineages of swine influenza A viruses, European avian-like（EA） H1N1 swine IAV has been dominant since 2005 in China and caused infections in humans in 2010. Highly sensitive and specific methods of detection are required to differentiate EA H1N1 swine IAVs from viruses belonging to other lineages and subtypes. In this study, a nested reverse transcription（RT）-PCR assay was developed to detect EA H1 swine IAVs. Two primer sets（outer and inner） were designed specifically to target the viral hemagglutinin genes. Specific PCR products were obtained from all tested EA H1N1 swine IAV isolates, but not from other lineages of H1 swine IAVs, other subtypes of swine IAVs, or other infectious swine viruses. The sensitivity of the nested RT-PCR was improved to 1 plaque forming unit（PFU） m L^（-1） which was over 10~4 PFU m L^（-1） for a previously established multiplex RT-PCR method. The nested RT-PCR results obtained from screening 365 clinical samples were consistent with those obtained using conventional virus isolation methods combined with sequencing. Thus, the nested RT-PCR assay reported herein is more sensitive and suitable for the diagnosis of clinical infections and surveillance of EA H1 swine IAVs in pigs and humans.
文摘OBJECTIVES: To detect blood AFPmRNA in the nude mice bearing with human hepatocellular carcinoma (HCC) by using nested reverse transcriptase polymerase chain reaction (nested RT-PCR), and assess its significance in HCC distant metastasis. METHOD: We detected 20 blood samples from the nude mice bearing with human HCC by nested RT-PCR to find out AFPmRNA. RESULT: AFPmRNA was detected in 6 blood samples from the nude mice hearing with human HCC (30. 0%), in which 4 mice developed distant metastasis. CONCLUSION: AFPmRNA may be used as an efficient and sensitive marker to detect blood spread of HCC cells. It can predict the occurrence of HCC distant metastasis.
基金supported by the grants from the National"863" Programme (2006AA10A2041)Development Programme of Science and Technology,Chengguan District of Gansu province (08-5-4)
文摘Reverse transcription polymerase chain reaction (RT-PCR) was used for the detection of classical swine fever virus (CSFV) in blood and tissue samples of field cases and experimentally inoculated pigs. The distribution of CSFV in different organ samples showed some discrepancies in infected pigs. Four weaner pigs were inoculated with C-strain vaccine virus, then samples of spleen, tonsil, lung, mesenteric lymph node, kidney and brain were collected after slaughter and tested for E2 and NS5B genes using one-step RT-PCR and nested RT-PCR. Using the same method, 12 field cases were simultaneously studied. A discrepancy of CSFV in different samples was found upon detecting the target gene. The most reliable diagnostic organs were spleen and tonsil, and the nested RT-PCR assay provided a highly sensitive and specific method with comparable performance to the one-step RT-PCR assay.
文摘Nested simulation encompasses the estimation of functionals linked to conditional expectations through simulation techniques.In this paper,we treat conditional expectation as a function of the multidimensional conditioning variable and provide asymptotic analyses of general nonparametric least squared estimators on sieve,without imposing specific assumptions on the function’s form.Our study explores scenarios in which the convergence rate surpasses that of the standard Monte Carlo method and the one recently proposed based on kernel ridge regression.We use kernel ridge regression with inducing points and neural networks as examples to illustrate our theorems.Numerical experiments are conducted to support our statements.
基金supported by China National Science Foundations(Nos.62371225,62371227)。
文摘Sparse array design has significant implications for improving the accuracy of direction of arrival(DOA)estimation of non-circular(NC)signals.We propose an extended nested array with a filled sensor(ENAFS)based on the hole-filling strategy.Specifically,we first introduce the improved nested array(INA)and prove its properties.Subsequently,we extend the sum-difference coarray(SDCA)by adding an additional sensor to fill the holes.Thus the larger uniform degrees of freedom(uDOFs)and virtual array aperture(VAA)can be abtained,and the ENAFS is designed.Finally,the simulation results are given to verify the superiority of the proposed ENAFS in terms of DOF,mutual coupling and estimation performance.
