Urinary prothrombin fragment 1 (UPTFl) is a potent inhibitor of urinary stone formation. UPTF1 exerts such inhibitory effect by effective 7-carboxylation in which vitamin K epoxide reductase complex subunit 1 (VKO...Urinary prothrombin fragment 1 (UPTFl) is a potent inhibitor of urinary stone formation. UPTF1 exerts such inhibitory effect by effective 7-carboxylation in which vitamin K epoxide reductase complex subunit 1 (VKORC1), the rate-limiting enzyme, is involved. This study examined the correlation between VKORC1 expression and calcium oxalate urolithiasis. The renal cortex samples were obtained from patients undergoing nephrectomy and then divided into 3 groups: urolithiasis group, control group A [hydronephrosis-without-stone (HWS) group], control group B (normal control group), The localization and expression of VKORC1 in renal tissues were determined by using immunohistochemistry, immunofluorescence microscopy, Western blotting and SYBR Green I real-time reverse-transcription PCR. The rapid amplification of cDNA ends (RACE) were conducted to obtain the 3'- and 5'-untranslated region (UTR) of VKORC1. The results showed that VKORC1 was located in the cytoplasm of renal tubular epithelial cells. The expression of VKORC1 in the uro- lithiasis group was significantly lower than that in the other two control groups (P〈0.05). Moreover, the 3'- and 5'-UTR sequence of the VKORC1 gene was successfully cloned. No insertion or deletion was found in the 3'- and 5'-UTR. However, a 171-bp new base sequence was discovered in the up- stream of 5'-UTR end in the urolithiasis group. It was concluded that the decreased expression of VKORC 1 may contribute to the development of calcium oxalate urolithiasis in the kidney.展开更多
In the existing Statistics and Econometrics literature, there does not exist a statistical test which may test for all kinds of roots of the characteristic polynomial leading to an unstable dynamic response, i.e., pos...In the existing Statistics and Econometrics literature, there does not exist a statistical test which may test for all kinds of roots of the characteristic polynomial leading to an unstable dynamic response, i.e., positive and negative real unit roots, complex unit roots and the roots lying inside the unit circle. This paper develops a test which is sufficient to prove dynamic stability (in the context of roots of the characteristic polynomial) of a univariate as well as a multivariate time series without having a structural break. It covers all roots (positive and negative real unit roots, complex unit roots and the roots inside the unit circle whether single or multiple) which may lead to an unstable dynamic response. Furthermore, it also indicates the number of roots causing instability in the time series. The test is much simpler in its application as compared to the existing tests as the series is strictly stationary under the null (C01, C12).展开更多
基金supported by a grant from the National Natural Science Foundation of China(No.30901482)
文摘Urinary prothrombin fragment 1 (UPTFl) is a potent inhibitor of urinary stone formation. UPTF1 exerts such inhibitory effect by effective 7-carboxylation in which vitamin K epoxide reductase complex subunit 1 (VKORC1), the rate-limiting enzyme, is involved. This study examined the correlation between VKORC1 expression and calcium oxalate urolithiasis. The renal cortex samples were obtained from patients undergoing nephrectomy and then divided into 3 groups: urolithiasis group, control group A [hydronephrosis-without-stone (HWS) group], control group B (normal control group), The localization and expression of VKORC1 in renal tissues were determined by using immunohistochemistry, immunofluorescence microscopy, Western blotting and SYBR Green I real-time reverse-transcription PCR. The rapid amplification of cDNA ends (RACE) were conducted to obtain the 3'- and 5'-untranslated region (UTR) of VKORC1. The results showed that VKORC1 was located in the cytoplasm of renal tubular epithelial cells. The expression of VKORC1 in the uro- lithiasis group was significantly lower than that in the other two control groups (P〈0.05). Moreover, the 3'- and 5'-UTR sequence of the VKORC1 gene was successfully cloned. No insertion or deletion was found in the 3'- and 5'-UTR. However, a 171-bp new base sequence was discovered in the up- stream of 5'-UTR end in the urolithiasis group. It was concluded that the decreased expression of VKORC 1 may contribute to the development of calcium oxalate urolithiasis in the kidney.
文摘In the existing Statistics and Econometrics literature, there does not exist a statistical test which may test for all kinds of roots of the characteristic polynomial leading to an unstable dynamic response, i.e., positive and negative real unit roots, complex unit roots and the roots lying inside the unit circle. This paper develops a test which is sufficient to prove dynamic stability (in the context of roots of the characteristic polynomial) of a univariate as well as a multivariate time series without having a structural break. It covers all roots (positive and negative real unit roots, complex unit roots and the roots inside the unit circle whether single or multiple) which may lead to an unstable dynamic response. Furthermore, it also indicates the number of roots causing instability in the time series. The test is much simpler in its application as compared to the existing tests as the series is strictly stationary under the null (C01, C12).