Influence of Transportation on the Serum Concentrations of the Cardiac Biomarkers Troponin I and Creatine Kinase-myocardial Band (CK-MB) and on Cortisol and Lactate in Horses

The objective of this study was to determine the influence of transportation on the serum concentrations of the cardiac biomarkers troponin I (cTnI) and creatine kinase-myocardial band (CK-MB) and on cortisol and lactate in horses. For this purpose, 10 horses were transported for 300 km. Blood samples were collected 24 hours before transport (T0), just before transport (T1), during transport at 50 km (T2), 100 km (T3), 200 km (T4), and 300 km (T5). An additional blood sample (T6) was collected 24 hours after transport. The median resting basal cTnI values in the horses were at T0, 0.000 ± 0.007 ng/mL and at T1, 0.01 ± 0.007 ng/mL. The median resting basal CK-MB values in the horses were at T0, 0.19 ± 0.05 ng/mL and at T1, 0.16 ± 0.05 ng/mL. Statistical analyses showed no significant differences of cTnI and CK-MB among the measured values (T0–T6). On the other side, the cortisol and lactate concentrations increased significantly (P < .01) at T2, T3, T3, and T4 compared with the resting values at T0. At T6, cortisol and lactate concentrations had returned to pretransport values, with no statistically significant differences compared with pretransport concentrations. In conclusion, the 300-km transportation of the horses did not influence the levels of the cardiac biomarkers, cTnI and CK-MB. The serum concentrations of cortisol and lactate, on the other side, increased significantly. The possible influence of transportation for longer distances or under more stressful conditions (higher temperature or in horses not used for transportation) on cTnI and CK-MB concentrations needs to be further investigated.     

Cardiac troponins as indicators of acute myocardial damage in dogs

Cardiac troponin I (cTnI) and T (cTnT) have a high sequence homology across phyla and are sensitive and specific markers of myocardial damage. The purpose of this study was to evaluate the Cardiac Reader, a human point-of-care system for the determination of cTnT and myoglobin, and the Abbott Axsym System for the determination of cTnI and creatine kinase isoenzyme MB (CK-MB) in healthy dogs and in dogs at risk for acute myocardial damage because of gastric dilatation-volvulus (GDV) and blunt chest trauma (BCT). In healthy dogs (n = 56), cTnI was below detection limits (<0.1 microg/L) in 35 of 56 dogs (reference range 0-0.7 microg/L), and cTnT was not measurable (<0.05 ng/mL) in all but 1 dog. At presentation, cTnI, CK-MB, myoglobin, and lactic acid were all significantly higher in dogs with GDV (n = 28) and BCT (n = 8) than in control dogs (P < .001), but cTnT was significantly higher only in dogs with BCT (P = .033). Increased cTnI or cTnT values were found in 26 of 28 (highest values 1.1-369 microg/L) and 16 of 28 dogs (0.1-1.7 ng/mL) with GDV, and in 6 of 8 (2.3-82.4 microg/L) and 3 of 8 dogs (0.1-0.29 ng/mL) with BCT, respectively. In dogs suffering from GDV, cTnI and cTnT increased further within the first 48 hours (P < .001). Increased cardiac troponins suggestive of myocardial damage occurred in 93% of dogs with GDV and 75% with BCT. cTnI appeared more sensitive, but cTnT may be a negative prognostic indicator in GDV. Both systems tested seemed applicable for the measurement of canine cardiac troponins, with the Cardiac Reader particularly suitable for use in emergency settings.     

人Troponin I的表达载体构建诱导表达和纯化及活性测定

以人肝脏cDNA文库为模板,通过PCR方法扩增出Tropon in基因,将其克隆到pCR-TOPO质粒中,构建表达质粒pET-22 b(+)-TnI,转化大肠杆菌BL 21(DE 3)-RPX并进行诱导表达,表达的目的蛋白占菌体总蛋白的20%以上并主要以可溶形式存在。建立了Tropon in I的非亲和色谱纯化工艺,纯化后蛋白产量约为20 mg/L,纯度在90%以上。体外活性实验表明重组蛋白具有良好的抗血管生成。     

Sex-based differences in plasma chemistry and cardiac marker test results in Siamese fighting fowl

BACKGROUND: Variations in the results of plasma chemistry analysis as a function of sex have rarely been demonstrated in avian species. OBJECTIVE: The aim of the present study was to investigate sex-related differences in values for routine biochemical variables, including conventional muscle enzymes, and novel cardiac markers in female and male Siamese fighting fowl. METHODS: Plasma chemistry analytes and cardiac marker proteins (creatine kinase-MB and cardiac troponin T) were measured in 70 Siamese fighting fowl using automated chemistry and immunoassay analyzers. Data were compared by 2-tailed t tests between sexes, and Spearman rank correlation between conventional and novel cardiac markers. RESULTS: Male fowl had significantly higher uric acid concentration and gamma-glutamyltransferase activity; whereas, female fowl had significantly higher total cholesterol, triglycerides, and calcium concentrations, and alkaline phosphatase activity. As compared with female fowl, the fighting cocks also had significantly higher plasma concentrations of creatine kinase-MB and cardiac troponin T. Significant correlations between cardiac troponin T, but not creatine kinase-MB, and the activities of conventional muscle enzymes (creatine kinase, aspartate aminotransferase and lactate dehydrogenase) were observed in male but not in female fowl. CONCLUSION: These results indicate that sex-specific differences exist for several biochemical parameters and cardiac marker proteins in fighting fowl, and that such differences should be considered in interpreting laboratory test results.     

Elimination half‐life of intravenously administered equine cardiac troponin I in healthy ponies

Reasons for performing study: To date, no information is available on the true biological elimination half‐life (T_1/2) of cardiac troponin I (cTnI) in the equine species. Such data are required to better evaluate the optimal time to acquire the cTnI sample following acute myocardial injury. Objective: To determine the T_1/2 of equine cTnI. Methods: Four healthy ponies received i.v. injections of recombinant equine cTnI. Plasma cTnI concentrations were measured with a point‐of‐care cTnI analyser at multiple time points after injection. Standard pharmacokinetic analysis was performed to establish the T_1/2 of cTnI. Results: The average T_1/2 of cTnI was determined to be 0.47 h using a single rate elimination model. Conclusion: The elimination of recombinant equine cTnI following i.v. administration is very rapid. Establishing the T_1/2 of troponin provides critical information in understanding the clinical application of this cardiac biomarker in equine practice.     

主动脉内球囊反搏术治疗急性心肌梗死的疗效和安全性观察

目的观察主动脉内球囊反搏术（IABP）治疗急性心肌梗死（AMI）的疗效和安全性。方法 80例AMI患者随机分为IABP组和对照组,每组40例。两组均给予WHO规定的标准基础治疗方案及PCI治疗,IABP组在PCI前使用IABP治疗。观察治疗前后两组脑利钠肽水平、肌钙蛋白I水平、左心室舒张末期容积（LVEDV）、左心室收缩末期容积（LVESV）和射血分数变化、治疗后30d内主要心血管事件。结果与对照组比较,IABP的使用显著降低心肌梗死后1周脑利钠肽及肌钙蛋白I水平（P〈0.01）,缩小LVEDV和LVESV（P〈0.01或0.05）,提高LVEF（P〈0.01）,降低30d内主要心血管事件的发生率（P〈0.01）。结论 IABP的使用能改善梗死后心肌缺血程度、心室压力、容量负荷和心室重构,从而改善AMI患者的预后。     

Biochemical markers of cardiac injury in normal, surviving septic, or nonsurviving septic neonatal foals

The cardiac biomarkers cardiac troponin T (cTnT) and I (cTnI) and the cardiac isoenzyme of creatine kinase (CKMB) are used extensively in human medicine to diagnose and provide valuable prognostic information in patients with ischemic, traumatic, and septic myocardial injury. We designed a study to establish normal values for these markers in healthy, neonatal foals and to compare them with values obtained from septic neonates in a referral hospital population. The 25th, 50th, 75th, and 95th percentiles for cTnI and CKMB in the healthy-foal population were 0.08, 0.14, 0.25, 0.49 ng/mL and 1.4, 2.3, 4.0, 7.4 ng/mL, respectively. The values obtained for cTnT were frequently (43/52 foals; 83%) below the lower limit of detection of the assay (0.009 ng/mL), but the median and range were 0.009 and 0.009-0.041 ng/mL, respectively. In the septic foal population, the 25th, 50th, 75th, and 95th percentile values for cTnI and CKMB were 0.05, 0.12, 0.22, and 1.10 ng/mL and 2.0, 4.4, 7.8, and 24 ng/mL, respectively. The values obtained for cTnT were less frequently below the lower limit of detection (23/38 foals; 60%) compared with the healthy foal population, and the median and range were 0.009 and 0.009-0.20 ng/mL, respectively. Significantly higher values were observed for cTnT and CKMB in septic foals compared with the healthy neonatal foal population, but there were no differences among septic foals in survivors compared with nonsurvivors. These findings suggest that myocardial injury occurs during septicemia in neonatal foals but that the injury is not associated with survival among septic foals.