Generation, characterization, and application in serodiagnosis of recombinant swine vesicular disease virus-like particles

Swine vesicular disease (SVD) is a highly contagious viral disease that causes vesicular disease in pigs. The importance of the disease is due to its indistinguishable clinical signs from those of foot-and-mouth disease, which prevents international trade of swine and related products. SVD-specific antibody detection via an enzyme-linked immunosorbent assay (ELISA) is the most versatile and commonly used method for SVD surveillance and export certification. Inactivated SVD virus is the commonly used antigen in SVD-related ELISA. A recombinant SVD virus-like particle (VLP) was generated by using a Bac-to-Bac baculovirus expression system. Results of SVD-VLP analyses from electron microscopy, western blotting, immunofluorescent assay, and mass spectrometry showed that the recombinant SVD-VLP morphologically resemble authentic SVD viruses. The SVD-VLP was evaluated as a replacement for inactivated whole SVD virus in competitive and isotype-specific ELISAs for the detection of antibodies against SVD virus. The recombinant SVD-VLP assay produced results similar to those from inactivated whole virus antigen ELISA. The VLP-based ELISA results were comparable to those from the virus neutralization test for antibody detection in pigs experimentally inoculated with SVD virus. Use of the recombinant SVD-VLP is a safe and valuable alternative to using SVD virus antigen in diagnostic assays.

Cerebrovascular blood flow dynamic changes in fetuses with congenital heart disease.

OBJECTIVE: The aim of this study was to determine whether the type of congenital heart disease (CHD) or heart function influence fetal cerebrovascular blood flow dynamics. METHODS: Doppler flow velocimetry was performed in the umbilical artery (UA) and middle cerebral artery (MCA), and the ratio of the UA pulsatility index (PI) to the MCA PI (U/C PI) was determined in 45 fetuses with CHD at 20-40 weeks' gestational age. The control group consisted of 275 healthy fetuses matched for gestational age. Individual PI measurements were converted into Z-scores for statistical analysis. RESULTS: Fetuses with CHD (n = 45) had an increased UA PI (p = 0.001) and U/C PI (p < 0.001) when compared to controls. There was no significant difference in the MCA PI between fetuses with CHD (n = 45) and controls (n = 275), while fetuses with CHD complicated by congestive heart failure (CHF) (n = 10) had a decreased MCA PI (p < 0.001) compared to controls. CONCLUSIONS: The lower PIs observed in the MCA of fetuses with CHD complicated by CHF represents a marker of cerebral vasodilation that is due to cerebral hypoxemia and limiting perfusion. The heart function and type of CHD have an impact on fetal cerebrovascular blood flow distribution and this may contribute to the cause of abnormal neurologic development in these fetuses.

Dendranthema morifolium attenuated the reduction of contraction of isolated heart and cardiomyocytes induced by ischemia/reperfusion / 中国病理生理杂志

AIM: To investigate the effect of Dendranthema morifolium (Ramat) Tzvel (DM) on isolated rat heart and ventricular myocytes during ischemia/anoxia and reperfusion/reoxygenation.METHODS: The Langendorff perfused rat hearts were used to measure intraventricular pressure and coronary flow. The cell contraction and intracellular calcium transient in enzymatically isolated ventricular myocytes were determined. RESULTS: (1) DM (0.5 g/L) significantly attenuated the inhibitory effects induced by ischemia/reperfusion on left ventricular developed pressure (LVDP), ?dp/dt max, coronary flow and LVDP?HR, meanwhile increased the content of SOD and decreased the content of MDA in the myocardium; (2) DM (0.5 g/L) attenuated the inhibitory effects of anoxia and reoxygenation on [Ca 2+]i transient and cell contraction in isolated ventricular myocytes. CONCLUSION: DM attenuated the effects on contractility and intracellular calcium induced by ischemia/anoxia and reperfusion/reoxygenation in the isolated rat heart and the ventricular myocytes. The mechanism might be related to increase in SOD activity and maintaining [Ca 2+]i homeostasis.

Salvia miltiorrhiza antagonized the alterations of contraction and intracellular calcium of rat ventricular cardiomyocytes induced by anoxia and reoxygenation / 中国病理生理杂志

AIM: To study the effect of salvia miltiorrhiza (SM) on cell contraction and intracellular calcium of enzymatically isolated rat ventricular myocytes during normoxia and anoxia/reoxygenation. METHODS: Contraction and intracellular calcium were determined with video tracking system and spectrofluorometric method, and the chemical anoxic method was employed. RESULTS: The ?d L /d t max , dL of cell contraction and the amplitude of [Ca 2+ ] i in the cardiomyocytes following SM treatment were decreased in a dose-dependent manner. During anoxia, the ?d L /d t max , dL and amplitude of [Ca 2+ ] i were decreased, while the diastolic Ca 2+ level was elevated compared with control group. All the contractile parameters and the diastolic Ca 2+ level were back toward pretreatment values during reoxygenation, but could not return to control level. After the treatment with SM (3 g/L), ?d L /d t max and dL of cell contraction and the amplitude of [Ca 2+ ] i were higher and the diastolic Ca 2+ level was lower than those in anoxia/reoxygenation group. CONCLUSION: SM antagonized effects of anoxia and reoxygenation on cell contraction and intracellular calcium in isolated ventricular myocytes.