1.A Secretive Pichia pastoris Expression Vector for Direct PCR Product Cloning
Chao ZHANG ; Gang LIU ; Shao-Wen YU ; Miao XING ;
China Biotechnology 2006;0(01):-
A secretive expression vector of Pichia pastoris system which can be used for the direct cloning of PCR products was constructed,and was verified through the expression of recombinant cellobiohydrolase II in Pichia pastoris.A randomly selected fragment was amplified with properly designed primers by PCR.The XhoI and Eam1105Ⅰ restriction sites were included in the 5'end of the fragment,and the Eam1105Ⅰ and XbaI restriction sites were included in its 3'end.The PCR amplified product was inserted into the P.pastoris expression plasmid pPICZ?A through XhoI and XbaI restriction sites and the resultant plasmid was digested with Eam1105Ⅰ,and lastly the big fragment was recovered,generating the P.pastoris expressive Tvector pPICZ?T.Then the cellobiohydrolase II of T.reesei was successfully expressed in P.pastoris with this expressive Tvector.Such results indicated that the constructed expression Tvector was convenient for PCR product cloning,and was effective for heterologous protein expression in P.pastoris.On the other hand,the application of the expression Tvector avoided the introduction of additional amino acids at the Nterminus of the expressed protein,which generally occurred when normal expression vectors were used in secretive expression system.
2.Arterial baroreflex function and left ventricular hypertrophy
Academic Journal of Second Military Medical University 2004;25(4):448-448
It is well known that the arterial baroreflex(ABR)plays a key role in the regulation of heart rate and stabilization of blood pressure.Currently,it appears that ABR dysfunction is involved in the pathophysiology of cardiovascular disease states.Since the mid-1990s,a number of studies have been carried out in our laboratory to explore the pathological significance of ABR function in cardiovascular damage.This minireview summarizes our research work on the topic of ABR and left ventricular hypertrophy(LVH).On the basis of discussion concerning the importance of ABR dysfunction in hypertensive LVH and sinoaortic denervation-induced LVH,we advance a new strategy for reversal of LVH,that is,restoration of impaired ABR function.We tested this hypothesis in animal models with ABR deficiency.It was found that improvement of impaird ABR function with long-term treatment of ketanserin or candesartan was accompanied by reversal of LVH.The preliminary results indicate that it is feasible to target ABR for treatment of LVH.
3.Arterial baroreflex function and left ventricular hypertrophy
Academic Journal of Second Military Medical University 2004;25(4):448-448
It is well known that the arterial baroreflex(ABR)plays a key role in the regulation of heart rate and stabilization of blood pressure.Currently,it appears that ABR dysfunction is involved in the pathophysiology of cardiovascular disease states.Since the mid-1990s,a number of studies have been carried out in our laboratory to explore the pathological significance of ABR function in cardiovascular damage.This minireview summarizes our research work on the topic of ABR and left ventricular hypertrophy(LVH).On the basis of discussion concerning the importance of ABR dysfunction in hypertensive LVH and sinoaortic denervation-induced LVH,we advance a new strategy for reversal of LVH,that is,restoration of impaired ABR function.We tested this hypothesis in animal models with ABR deficiency.It was found that improvement of impaird ABR function with long-term treatment of ketanserin or candesartan was accompanied by reversal of LVH.The preliminary results indicate that it is feasible to target ABR for treatment of LVH.
4.Expression of ADAM8 in hepatocellular carcinoma and its clinical significance
Yun ZHANG ; Benshun HU ; Yongfei TAN ; Zhijun GE ; Chao JIANG ; Miao ZHANG ; Xiaotian YU ; Haifeng YU
Chinese Journal of Hepatobiliary Surgery 2013;(2):116-119
Objective To investigate the expression of ADAM8 in patients with hepatocellular carcinoma (HCC) and its clinical significance.Methods The protein expression of ADAM8 in HCC tissues was analyzed using immunohistochemical analysis.Serum levels of ADAM8 were measured by ELISA in 126 patients with HCC,50 patients with liver cirrhosis (LC) and 50 healthy individuals.The relationship between patients' pathological features and serum ADAM8 level was analyzed.Results Immunohistochemical analysis showed that ADAM8 expression was associated closely with serum AFP elevation,tumor size,histological differentiation,and tumor stage.The ELISA assay showed that the serum levels of ADAM8 in the HCC were significantly higher than those in LC and healthy groups.Kaplan-Meier survival analysis showed that high expression of serum ADAM8 exhibited a significant correlation with poor prognosis for HCC patients.Multivariate analysis revealed that serum ADAM8 expression is an independent prognostic parameter for the overall survival rate of HCC patients.Conclusion ADAM8 expression was closely associated with tumor size,serum AFP elevation,tumor differentiation,tumor stage and prognosis in hepatocellular carcinoma.Therefore,ADAM8 expression may serve as a biomarker for predicting the prognosis of patients in hepatocellular carcinoma.
5.Experimental study of superparamagentic scaffolds used to repair rabbit mandibular defect
Shanshan DING ; Yijun YU ; Chao LIU ; He ZHANG ; Xincong LI ; Weibin SUN ; Leiying MIAO
Journal of Medical Postgraduates 2017;30(3):251-256
Objective Sperparamagnetic material is widely used in tumor localization and treatment , but there are still few studies in bone tissue engineering .This study aims to investigate the osteogenic efficiency of superparamagnetic scaffolds poly lactic acid hydroxy acetic acid (PLGA)/iron-doped hydroxyapatite (Fe-HA) for repairing rabbit mandibular defects , as well as evaluating the biocompatibility of the material . Methods 36 New Zealand rabbits were randomly selected and randomly divided into 6 groups, control without and with static magnetic field ( SMF ) groups ( no material is implanted), PLGA scaffold without and with SMF groups (implanted PLGA), PLGA/Fe-HA scaffold without and with SMF groups ( im-planted PLGA/Fe-HA), each group has 6 rabbits.We created bilat-eral mandibular defect models , executed the rabbits at 4 weeks and 12 weeks post-surgery, marked the mandibular specimens which detected by general observation, Micro-CT and HE staining, and ana-lyzed the results of bone mineral density in defect area .The hematological detection , pathological examination of liver and kidney sam-ples were carried out at 12 weeks pot-surgery.. Results The PLGA/Fe-HA scaffold without and with SMF groups began to appear rough defect area edge , decreased defect diameter , new bone formation from 4 weeks; the defect area formed a smooth , continuous bone repair from 12 weeks.The PLGA scaffold without and with SMF groups appeared rough , irregular callus repair , visible boundary between defect edge and normal bone tissue .There are still have part of unrepaired bone defect in the center of defect area in the control without and with SMF groups.At 12 weeks , the bone mineral density of PLGA/Fe-HA scaffold with SMF group [(572.50±19.09) mgHA/cm3] , respectively, compared with the PLGA scaffold with SMF group [(467.00±6.24)mgHA/cm3], the control with SMF scaffold group [(480.00±2.08) mgHA/cm3], the PLGA/Fe-HA scaffold without SMF group [(461.00±19.79)mgHA/cm3], the PL-GA scaffold without SMF group [(446.00±11.31)mgHA/cm3] and the control without SMF group [(422.00±28.28) mgHA/cm3], all the differences were statistically significant ( P<0.05).The bone mineral density of PLGA/Fe-HA scaffold with SMF group at 4 weeks [(572.50±19.09)mgHA/cm3] was significantly higher than that at 12 weeks [(276.00±28.28)mgHA/cm3] (P<0.05), the differences between 4 weeks and 12 weeks in other groups were statistically significant (P<0.05). Conclusion The superparama-gentic PLGA/Fe-HA scaffolds can promote the repair of bone defect , optimize the osteogenic effect of the material with SMF .Also ,the scaffold showed a good biocompatibility .
6.Methylation in Promoter Region of SLC6A2 Gene in Heart Failure Patients and Its Correlation with Qi Deficiency/Blood Stasis Syndrome.
Jie-wei LUO ; Xiao-rong MENG ; Fang-meng HUANG ; Dan HU ; Xiao YANG ; Xing-yu ZHENG ; Shi-chao WEI ; Miao-miao GUO ; Shi-ming WU ; Hong-yi CHEN
Chinese Journal of Integrated Traditional and Western Medicine 2015;35(12):1448-1454
OBJECTIVETo explore the methylation status in promoter region of norepinephrine transporter gene (NET, SLC6A2) in heart failure ( HF) patients and its correlation with qi deficiency/blood stasis syndrome (QDS/BSS).
METHODSThirty-six patients with heart failure (NYHA classification III to IV) were recruited in the study (as the heart failure group) and their scores of QDS/BSS were evaluated. Besides, a healthy elderly group (30 cases) and a healthy youth group (30 cases) were also set up. They were recruited from Physical Examination Center of Fujian Provincial Hospital. Pyrosequencing was applied to detect the methylation in promoter region of SLC6A2 gene, and the total methylation index (MTI) of CpG island was calculated. The correlation between the methylation status in promoter region of SLC6A2 and scores of QDS/BSS was assessed using Pearson and Partial analyses. Risk factors were screened and adjusted using Logistic regression.
RESULTSBy one-factor analysis of variance, the total MTI in the HF group (219.72% ± 54.03%) was obviously higher than that in the healthy elderly group (194.47% ± 34.92%) and the healthy youth group (161.60% ± 41.11%) (all P < 0.05). Meanwhile, the total MTI was higher in the healthy elderly group than in the healthy youth group (P < 0.01). By covariance analysis , after controlling age and BMI, the total MTI was higher in the HF group than in the healthy elderly group (P = 0.041), while it was higher in the healthy elderly group than in the healthy youth group (P = 0.016). Age was found to play an essential role in affecting MTI of SLC6A2 gene promoter region among the 3 groups (F = 16.447, P = 0.01). The total MTI was quite lower in the healthy youth group. Results of Partial correlation analysis showed MTI was positively correlated with scores of qi deficiency and blood stasis respectively (r = 0.494 and 0.419 respectively, both P < 0.05). Logistic regression analysis showed after adjusting confounding factors, the relative risk (OR value) of total MTI of SLC6A2 gene in promoter region was 1.038 (95% CI, 1.006 to 1.071, P = 0.020).
CONCLUSIONSAbnormally elevated methylation of the promoter region of SLC6A2 gene is one of risk factors for HF. In addition, the degree of methylation of the promoter region of SLC6A2 gene was positively correlated with the severity of QDS/BSS.
Adolescent ; Aged ; DNA Methylation ; Heart Failure ; genetics ; physiopathology ; Humans ; Logistic Models ; Medicine, Chinese Traditional ; Norepinephrine Plasma Membrane Transport Proteins ; genetics ; Promoter Regions, Genetic ; Qi
7.Contribution of blood pressure variability to the effect of nitrendipine on end-organ damage in spontaneously hypertensive rats
Jian-Guo LIU ; Li-Ping XU ; Zheng-Xu CHU ; Chao-Yu MIAO ; Ding-Feng SU
Academic Journal of Second Military Medical University 2004;25(4):406-406
Objective:It has been proposed that blood pressure variability(BPV) is positively related to end-organ damage(EOD) in hypertension.The present work was designed to observe the effects of long-term treatment with nitrendipine and hydralazine on BPV and EOD in spontaneously hypertensive rats(SHR),to examine the hypothesis that lowering BPV with an antihypertensive drug is an important factor in organ protection.Design and methods:Drugs were mixed in rat chow.After 4 months of drug administration,blood pressure was recorded continuously in conscious freely moving rats for 24 h.The heart,kidneys,and brain were then isolated and examined.Results:It was found that nitrendipine significantly decreased blood pressure and BPV,and significantly decreased EOD score in SHR.Hydralazine decreased blood pressure,but did not lower BPV.No effect on EOD was found in hydralazine-treated rats.In control rat(n=38),EOD score was weakly related to systolic blood pressure(r=0.331,P<0.05) and closely related to long-term systolic BPV(r=0.551,P<0.01).In nitrendipine-treated rats,EOD score was closely related to long-term systolic BPV(r=0.602,P<0.01),but not to blood pressure level(r=0.174,P>0.05).Conclusion:BPV plays an important role in the organ-protecting effects of nitrendipine.
8.Effects of glucose-insulin-potassium on baroreflex sensitivity, left ventricular function and ventricular arrhythmia in the subacute phase of myocardial infarction in rats
Jian-Guo LIU ; He SHU ; Fu-Ming SHEN ; Chao-Yu MIAO ; Ding-Feng SU
Academic Journal of Second Military Medical University 2004;25(4):433-433
Objective:Glucose-insulin-potassium(GIK) is clinically used for reducing mortality in acute myocardial infarction(MI). It is known that ventricular arrhythmia, left ventricular dysfunction and impaired baroreflex sensitivity(BRS) are the three major determinants for predicting the mortality after acute MI. The present work was designed to study the effects of GIK on BRS, ventricular arrhythmia, and left ventricular function in rats with coronary artery ligature. Sprague-Dawley rats were used and the myocardial infarction was produced by ligature of the left anterior descending artery. Five weeks after coronary artery ligation, BRS was measured in conscious state with a computerized blood pressure monitoring system and left ventricular function and electrocardiogram were determined in the anaesthetized state in the subacute phase of myocardial infarction. It was found that GIK did not affect the blood pressure and heart period in both conscious and anaesthetized rats. GIK did not enhance BRS, but reduced ventricular arrhythmia and improved left ventricular function by reducing left ventricular end diastolic pressure in anaesthetized rats with MI. It is proposed that reducing ventricular arrhythmia and improving left ventricular function contribute to the effect of GIK on reducing the mortality after MI.
9.Contribution of blood pressure variability to the effect of nitrendipine on end-organ damage in spontaneously hypertensive rats
Jian-Guo LIU ; Li-Ping XU ; Zheng-Xu CHU ; Chao-Yu MIAO ; Ding-Feng SU
Academic Journal of Second Military Medical University 2004;25(4):406-406
Objective:It has been proposed that blood pressure variability(BPV) is positively related to end-organ damage(EOD) in hypertension.The present work was designed to observe the effects of long-term treatment with nitrendipine and hydralazine on BPV and EOD in spontaneously hypertensive rats(SHR),to examine the hypothesis that lowering BPV with an antihypertensive drug is an important factor in organ protection.Design and methods:Drugs were mixed in rat chow.After 4 months of drug administration,blood pressure was recorded continuously in conscious freely moving rats for 24 h.The heart,kidneys,and brain were then isolated and examined.Results:It was found that nitrendipine significantly decreased blood pressure and BPV,and significantly decreased EOD score in SHR.Hydralazine decreased blood pressure,but did not lower BPV.No effect on EOD was found in hydralazine-treated rats.In control rat(n=38),EOD score was weakly related to systolic blood pressure(r=0.331,P<0.05) and closely related to long-term systolic BPV(r=0.551,P<0.01).In nitrendipine-treated rats,EOD score was closely related to long-term systolic BPV(r=0.602,P<0.01),but not to blood pressure level(r=0.174,P>0.05).Conclusion:BPV plays an important role in the organ-protecting effects of nitrendipine.
10.Effects of glucose-insulin-potassium on baroreflex sensitivity, left ventricular function and ventricular arrhythmia in the subacute phase of myocardial infarction in rats
Jian-Guo LIU ; He SHU ; Fu-Ming SHEN ; Chao-Yu MIAO ; Ding-Feng SU
Academic Journal of Second Military Medical University 2004;25(4):433-433
Objective:Glucose-insulin-potassium(GIK) is clinically used for reducing mortality in acute myocardial infarction(MI). It is known that ventricular arrhythmia, left ventricular dysfunction and impaired baroreflex sensitivity(BRS) are the three major determinants for predicting the mortality after acute MI. The present work was designed to study the effects of GIK on BRS, ventricular arrhythmia, and left ventricular function in rats with coronary artery ligature. Sprague-Dawley rats were used and the myocardial infarction was produced by ligature of the left anterior descending artery. Five weeks after coronary artery ligation, BRS was measured in conscious state with a computerized blood pressure monitoring system and left ventricular function and electrocardiogram were determined in the anaesthetized state in the subacute phase of myocardial infarction. It was found that GIK did not affect the blood pressure and heart period in both conscious and anaesthetized rats. GIK did not enhance BRS, but reduced ventricular arrhythmia and improved left ventricular function by reducing left ventricular end diastolic pressure in anaesthetized rats with MI. It is proposed that reducing ventricular arrhythmia and improving left ventricular function contribute to the effect of GIK on reducing the mortality after MI.