Objective To observe the changes of brain natriuretic peptide(BNP)in patients with myocardial infarction,and to assess the clinical value of BNP in the patients with myocardial infarction.Methods BNP was determined in 91 patients with myocardial infarction and in 90 normal cases,and the difference was studied between the area of myocardial infarction and the number of coronary arteries stenosis.Results BNP(ng/L)(155.03 ± 113.45,71.03 ±37.01)and LVEDd(cm)(5.11 ±0.51,4.56 ±0.43)were significantly increased in patients with myocardial infarction than that in normal cases(P＜0.01),but EF(%)(50.84 ±7.98,57.09 ±6.29)was lower than that in normal cases(P＜0.01).BNP and LVEDd were also significantly higher in patients with wide-anterior myocardial infarction than that in antero-septal,inferior and posterior wall myocardial infarction,but LVEF was lower.Conclusion The BNP level was higher in patients with myocardial infarction,especially in patients with wide-anterior myocardial infarction.BNP was a reliable bio-chemical marker which can evaluate the degree and prognosis of patients with myocardial infarction.

Over the past years efforts have been made by the government to improve the management of clinical laboratories.The government activities such as networking of quality assurance, development and implementation of clinical laboratory standards, and establishment of external quality control mechanisms have facilitated the improvement of clinical laboratory quality.Further definition and integration of clinical laboratory services, introduction of clinical laboratory pathologists and consultation and establishment of a permission mechanism are needed for improving the effectiveness of clinical laboratory services.Government regulations will continue to play an essential role in the clinical improvement process.

ObjectiveTo evaluate creatinine proficiency testing data by robust Z-score analysis.MethodsThe data were collected from three proficiency surveys of routine biochemical test in 2009,to which 1 179,1 169 and 1 168 laboratories participated respectively.Creatinine data were divided into Jaffe group and enzymatic group based on the analytical method used.The results tested by both methods were compared using Mann-Whitney test.The outliers were deleted using the TUKEY fence established by quartile values.The normality of raw data and trimmed data was tested using one-sample Kolmogorov-Smirnov test.The performance of the laboratories was assessed using robust Z-score,whose values were considered satisfactory when ｜ Z-score｜ ≤2,questionable when 2 ＜ ｜ Z-score ｜ ＜ 3 and unsatisfactory when ｜ Z-score ｜ ≥3.Results86.7％ results tested using Jaffe and enzymatic methods were not comparable.The raw data in all research groups were not normally distributed.After deletion of outliers,73.3％ trimmed data in most research groups were normally distributed.For the three proficiency tests in 2009,in Jaffe group,the satisfactory rates were 89.8％( 495/551 ),87.2％( 468/537 ) and 89.5％( 476/532 ) respectively,unsatisfactory rates were 3.3％ ( 18/551 ),6.5％ (35/537) and 4.5％ (24/532) respectively; while in enzymatic group,the satisfactory rates were 88.8％ (558/628),89.3％ (564/632) and 88.1％ (560/636) respectively,unsatisfactory rates were 5.6％( 35/628 ),5.2％ (33/632) and 6.6％(42/636) respectively.Conclusion It is reasonable to choose robust Z-score as a proficiency testing assessment index,because it avoids the influence of the outliers on evaluation results.

Objective To perform calibration verification for the blood glucose test in Hitachi and Olympus automatic biochemistry analyzers and present a method of calibration verification and evaluate the results.Methods The glucose test results were divided into two groups:Hitachi and Olympus groups according to the different analytical instruments.The calibration verification was performed following the current College of American Pathologists strategies.The slope and intercept of the calibration line were tested by one-sample t test and the percentage differences were calculated.The percentage differences were compared with allowable errors.If the slope and intercept had no statistically significant difference from 1 and 0 respectively and the percentage differences were within the limits of allowable errors,the calibration line was evaluated as verified 1 ; if the slope and intercept had no statistically significant difference from 1 and 0 respectively and at least one of the percentage differences exceeded the limits of allowable errors,the calibration line was evaluated as different 1 ; if the slope or intercept had statistically significant difference from 1 and 0 respectively and the percentage differences were within the limits of allowable errors,the calibration line was evaluated as verified 2; if the slope or intercept had statistically significant difference from 1 and 0 respectively and at least one of the percentage differences exceeded the limits of allowable errors,the calibration line was evaluated as different 2.Results In Hitachi group,verified 1,different 1,verified 2 and different 2 were 5.4％ ( 4/74 ),0.0％ ( 0/74 ),68.9％ ( 51/74 ) and 25.7％ ( 19/74 ),respectively.In Olympus group,verified 1,different 1,verified 2 and different 2 were 16.4％ (12/73),0.0％ (0/73),58.9％ (43/73) and 24.7％ ( 18/73 ),respectively.Conclusions The current College of American Pathologist strategies could be performed as a reasonable and feasible method for calibration verification.Most of participating laboratories ( 74.8％,110/147 passed the assessment of calibration verification.

Objective To investigate the linearity on testing creatinine in various assay instntments,in order to evaluate creatinine testing ability of clinical laboratories. Methods Statistically standard linearity and nonlinearity were judged via polynomial regression analysis recommended by EP6-A guideline. The imprecision of analytical data were analyzed and the average deviation of best fitting curve from linearity were determined by Dr. Kroll's EP6-A extended methods. In accordance with the instruments used, the testing data were divided into four groups: Beckman LX (28 Labs), Beckman CX ( 14 Labs), Hitachi (62 Labs)and Olympus (72 Labs) groups. Results This research found that in samples analyzed by Beckman LX,Beckman CX, Hitachi and Olympus instruments, the imprecision ranged from 0. 30%-3.01%, 0.09%-3.46%, 0. 14%-4. 91% and 0. 17% -16. 44%, respectively. The imprecision in one laboratory in Olympus group exceeded the acceptable limit, while the imprecision in the remaining laboratories were precision for linear survey. The average deviations of best fitting curve from linearity ranged from 0%-2. 38%, 0%-2. 51%, 0% -5.46% and 0% -4. 66%, respectively. The linearity with statistical significance were 21.4% (6/28), 35.7% (5/14), 11.3% (7/62) and 18. 1% (13/72), respectively. The linearity with clinical significance were 78.6% (22/28), 64. 3% (9/14), 88. 7% (55/62) and 80. 6% (58/72), respectively.The percentages of laboratories whose creatinine testing met the linearity criteria were 100% (28/28),100% ( 14/14 ), 100% ( 62/62 ) and 98. 6% ( 71/72 ), respectively. Conclusion Majority of the laboratories involved in the linearity survey present good capability for creatinine testing.

Objective To investigate the predictive value of serum aldosterone and Plasminogen activator inhibitor-1 ( PAI-1 ) levels to the severity of coronary artery lesions and the recent prognosis in acute coronary syndrome (ACS) patients underwent percutaneous coronary intervention(PCI). Methods The study included 160 consecutive patients admitted. All the patients received coronary angiography and were divided into two groups:control group and ACS group. The patients' blood samples were abtained at the root of aortic artery to measure the serum aldosterone and PAI-1 levels. We analyzed their relationship with the severity of coronary artery lesions. The patients were also divided into three groups( high-score group, moderate-score group,low-score group)according to Gensini accumulated points,we analyzed the difference of aldosterone and PAI-1 levels in three groups. The predictive values of aldosterone and PAI-1 to the recent pronosis of ACS patients underwent PCIwere assessed. Results ( 1 )The patients' serum aldosteeone and PAI-1 levels in ACS group were significantly higher than control group( all P <0. 05 ) ;(2)The aldosterone and PAI-1 levels in high-score group were higher than moderate-score group, and moderate-score group was higher than low-score group. (3)The serum aldosterone level in ACS patients was positively correlated with the PAI-1 level ( r = 0.213, all P < 0. 05 ). ( 4 ) Multiple factor Logistic regression analysis indicated that aldosterone, PAI-1 levels were srtong independent predictors for the recent prognosis of ACS patients underwent PCI. Conclusion The aldosterone ,PAI-1 levels in ACS patients were correlated with the severity of coronary artery lesions. Both of them were strong predictors for the recent prognosis of ACS patients underwent PCI.

Objective To study the effects of ischemia postconditioning(IPC) in reducing ischemia-reperfusion injury(IRI) in acute limp ischemia(ALI) and investigate the mechanism.Methods 45 New Zealand rabbits were treated with the method that combined high lipid diets and femoral intima injury by balloon inflation to build up limp atherosclerotic stenosis model,then they were randomly divided into three groups( each group 15 rabbits):control group;IR group and IPC group.Serum creatine phosphate kinase(CK),malondialehyde(MDA),superoxide dismutase (SOD) in three groups were measured before occlusion and 2 hours after sustaining reperfusion.The histological changes of limp skeletal muscle of experimental rabbits were analyzed and TUNEL method was used to access apoptosis of skeletal muscle cells.Results The levels of CK,M DA in IPC group were lower than IR group [ (7.49 ± 0.84)vs (8.19 ± 1.06),P＜0.05],[ (3.67 ±0.36) vs (4.06 ±0.55),P ＜0.05] while SOD level was higher than IR group [ (420.40 ± 30.94 ) vs ( 384.73 ± 44.12),P ＜ 0.05 ] ; The injury of skeletal muscles in I PC group was lighter than IR group and the apoptosis index of skeletal muscle cells was significantly decreased compared with that in IR group[(12.27+2.11)％ vs (16.62 ± 1.44)％,P＜0.01].Conclusion Applying IPC in acute limp ischemia could alleviate IRI and protect skeletal muscles.The mechanism was associated with oxidation resistance enhancing and the effects in reducing apoptosis of skeletal muscles induced by IRI.

Objective To investigate relationship of microalbuminuria (MAU) and insulin resistance (IR) to severity of coronary lesions in patients with acute coronary syndrome (ACS), and its predictive value for short-term prognosis in then.Methods In total, 162 ACS patients admitted to the department of cardiology, Guangzhou First People's Hospital, Guangzhou, Guangdong province during January 2008 to June 2009 were selected and divided into three groups according to their urine albumin excretion rate (UAER): 54 cases in normal group with UAER less than 20 μg/min, 62 cases in microalbuminuria group with UAER of (20-200)μg/min, and 46 cases in mass-albuminuria group with UAER more than 200 μg/min.Difference in IR (by homeostasis model assessment, HOMA ) and severity of coronary lesions among the three groups was assessed.Effects of baseline MAU and IR on main adverse cardiac events within the recent six months were observed in ACS patients after percutaneous coronary intervention (PCI).Results IR increased and coronary lesions aggravated as UAER increasing in all the three groups of ACS patients (P＜0.05 or P＜0.01).MAU associated with IR, with a coefficient of correlation of 0.366 (P＜0.01).Results of multivariate logistic regression analysis showed that both MAU and IR were strong independent predictors for main adverse cardiac events in ACS patients within six months after PCI.Conclusions MAU and IR associate with severity of coronary lesions in ACS patients, suggesting certain predictive value for main adverse cardiac events in short-term after PCI.

Objective To assess the roles of renalase and renal sympathetic nerve activity in patients with chronic heart failure (CHF). Methods Plasma renin activity (PRA), angiotensinⅠ (AngⅠ), angiotensin Ⅱ(AngⅡ),adrenaline (E), noradrenaline (NE) and renalase were determined in 60 patients with CHF (CHF group) and in 42 healthy cases (control group). Data were compared between patients with mild and serious CHF. Results PRA, E, NE and AngⅠincreased and renalase decreased in CHF group than those in control group. Compared with mild CHF, renalase and left ventricular ejection fraction decreased (P < 0.01, 0.034), while N-terminal pro-B-type natriuretic peptide (NT-proBNP) and PRA significantly increased (P<0.01). Linear correlation analysis showed that renalase was inversely correlated with Log NT-proBNP (r = -0.400, P = 0.002) and Log NE (r=-0.314, P = 0.014). Logistic regression analysis showed that NT-proBNP (OR = 6.963, 95%CI = 1.223 to 39.638), PRA (OR = 3.736, 95%CI = 1.031 to 13.540) and renalase (OR = 0.253, 95%CI = 0.069 to 0.927) were associated with increased NYHA classes. Conclusions PRA would increase while renalase would decrease in patients with CHF. PRA and renalase were correlated to the severity of CHF.

Objective To investigate the effect and mechanism of ischemic postconditioning (IPC) on myocardial perfusion levels of acute ST-segment elevation myocardial infarction (STEMI) patients having underwent primary percutaneous coronary intervention (PCI), and the safety of IPC. Methods One hundred and sixty patients with STEMI were enrolled, and they accepted the primary PCI therapy within the onset of 12 h. The patients were divided into 2 groups according the treatment method:control group (routine PCI group, 82 cases) and IPC group (78 cases). The ST-segment resolution, TIMI myocardial perfusion grade (TMPG), before and after PCI levels of nitrogen monoxidum (NO), endothelin (ET)-1, tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor (PAI)-1, rate of intraoperative complication were observed. The patients were followed up for 6 months, the rate of major adverse cardiac event (MACE) was recorded. Results The rates of ST-segment resolution and TMPG well in IPC group were significantly higher than those in control group:84.62%(66/78) vs. 67.07%(55/82) and 80.77%(63/78) vs. 64.63%(53/82), and the rate of ischemia-reperfusion injury in IPC group was significantly lower than that in control group: 7.69%(6/78) vs. 24.39%(20/82), and there were statistical differences ( P<0.05 or<0.01). The endothelial function and fibrinolysis activity indexes (NO, ET-1, t-PA and PAI-1 levels ) 7 d after PCI in IPC group were significantly better than those in control group: (52.37 ± 3.84) μmol/L vs. (50.95 ±3.85) μmol/L, (75.47 ±3.47) ng/L vs. (76.61 ±3.72) ng/L, (12.96 ±1.25) μg/L vs. (12.52 ±1.23) μg/L, (21.78 ±4.01)μg/L vs. (24.95±7.56)μg/L, and there were statistical differences (P<0.05 or<0.01). There was no statistical difference in the rate of intraoperative complication between 2 groups ( P>0.05). The rate of MACE in IPC group was significantly lower than that in control group:3.85% (3/78) vs. 14.63% (12/82), and there was statistical difference (P<0.05). Conclusions Applying IPC in patients with STEMI having underwent primary PCI is safe and can improve myocardial perfusion levels. The improvement of vessel endothelial function and fibrinolysis activity attained from IPC may be the major mechanism.