Unspecific elevation of plasma troponin‐T and CK‐MB after coronary surgery

Objective—Biochemical markers of myocardial injury are frequently elevated after cardiac surgery. It is generally accepted that release unrelated to permanent myocardial damage explains a proportion of these elevations. However, little is known about the magnitude and temporal characteristics of this diagnostic noise. One way to address this issue would be to study a group without permanent myocardial injury.

Design—The unique release kinetics of troponin‐T (permanent myocardial injury causes a sustained release of structurally bound troponin) were used to identify patients with no or minimal permanent myocardial injury. Blood was sampled from patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) before surgery, 3 and 8?h after unclamping the aorta, and each morning until postoperative day 4, for analysis of enzymes and troponin‐T. From 302 consecutive patients a subgroup was identified that fulfilled the following criteria: (a) normalized troponin‐T levels ≤postoperative day 4; (b) no ECG changes indicating myocardial injury.

Results—Seventy‐seven patients fulfilled the criteria above and in this subgroup troponin‐T (2.08?±?1.42?μg/l; range 0.35–8.99?μg/l) peaked at the 3?h recording and creatine kinase monobasic (CK‐MB) (28.6?±?11.3?μg/l; range 11.9–86.0?μg/l) peaked at the 8?h recording after unclamping the aorta.

Conclusion—Substantial early elevations of plasma CK‐MB and troponin‐T occurred in patients with no or minimal permanent myocardial injury after CABG. Unspecific release was most pronounced during the timeframe that is usually studied to evaluate myocardial protective strategies or to compare revascularization procedures.     

Damage and the repeated bout effect of arm,leg, and trunk muscles induced by eccentric resistance exercises

This study compared nine resistance eccentric exercises targeting arm, leg, and trunk muscles in one session for changes in maximal voluntary isometric contraction strength (MVC), delayed onset muscle soreness (DOMS), plasma creatine kinase (CK) activity, and myoglobin (Mb) concentration after the first and second bouts. Fifteen sedentary men (20‐25 years) performed 5 sets of 10 eccentric contractions with 80% of MVC load for the elbow flexors (EF), elbow extensors (EE), pectoralis, knee extensors (KE), knee flexors (KF), plantar flexors (PF), latissimus, abdominis, and erector spinae (ES) in a randomized order and repeated the same exercises 2 weeks later. MVC decreased at 1 (16%‐57%) to 4 (13%‐49%) days, DOMS developed (peak: 43‐70 mm), and CK activity (peak: 23 238‐207 304 IU/L) and Mb concentration showed large increases after the first bout. The magnitude of decrease in MVC was greater (P < 0.05) for EF, EE, and PEC than others and for KF than KE, PF, and ES. DOMS was greater (P < 0.05) for EF, EE, and ES than others. Changes in all measures were smaller (P < 0.05) after the second than the first bout, and the magnitude of the repeated bout effect was similar among the muscles. Plasma CK activity and Mb concentration did not increase significantly after the second exercise bout. It was concluded that muscle damage was greater for arm than leg muscles, and muscle proteins in the blood increased to a critical level after unaccustomed whole‐body resistance exercises, but the magnitude of damage was largely attenuated for all muscles similarly after the second bout.     

急性心肌梗死患者血清lncRNA p21表达水平及临床意义

目的 探究急性心肌梗死(AMI)患者血清lncRNA p21表达水平及临床意义。方法 选取河南科技大学第一附属医院心外科2019年1月至2021年1月收治的92例AMI患者(AMI组),根据冠脉病变程度分为轻度病变组(n=29)、中度病变组(n=43)和重度病变组(n=20);同期选择本院体检健康者92例为对照组。AMI患者在经皮冠状动脉植入术(PCI)术后随访24个月,将患者分为心血管不良事件(MACE)组(n=22)和非MACE组(n=70)。采用实时荧光定量聚合酶链式反应检测研究对象血清中lncRNA p21表达水平。采用Pearson法分析AMI患者血清lncRNA p21水平与肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)水平的相关性。采用受试者工作特征(ROC)曲线评价血清lncRNA p21水平预测AMI的价值。结果 与对照组相比,AMI组血清lncRNA p21相对表达水平较低(P＜0.05),CK-MB及cTnI水平较高(P＜0.05)。与轻度病变组相比,中度病变组、重度病变组血清lncRNA p21相对表达水平较低(P＜0.05),CK-MB、cTnI水平较高(P＜0.05);与中度病变组相比,重度病变组血清lncRNA p21相对表达水平较低(P＜0.05),CK-MB、cTnI水平较高(P＜0.05)。AMI患者血清lncRNA p21水平与cTnI、CK-MB水平均呈负相关(P＜0.05)。ROC曲线显示,lncRNA p21水平预测AMI的曲线下面积(AUC)为0.861,其灵敏度、特异度分别为70.70%、89.10%;lncRNA p21联合cTnI、CK-MB预测AMI的AUC为0.956,其灵敏度、特异度分别为89.10%、94.60%。与非MACE组相比,MACE组治疗前血清lncRNA p21相对表达水平较低(P＜0.05)。结论 AMI患者血清lncRNA p21表达水平下降,lncRNA p21对AMI具有一定的诊断价值。     

N-Acetylaspartate in the CNS: from neurodiagnostics to neurobiology

The brain is unique among organs in many respects, including its mechanisms of lipid synthesis and energy production. The nervous system-specific metabolite N-acetylaspartate (NAA), which is synthesized from aspartate and acetyl-coenzyme A in neurons, appears to be a key link in these distinct biochemical features of CNS metabolism. During early postnatal central nervous system (CNS) development, the expression of lipogenic enzymes in oligodendrocytes, including the NAA-degrading enzyme aspartoacylase (ASPA), is increased along with increased NAA production in neurons. NAA is transported from neurons to the cytoplasm of oligodendrocytes, where ASPA cleaves the acetate moiety for use in fatty acid and steroid synthesis. The fatty acids and steroids produced then go on to be used as building blocks for myelin lipid synthesis. Mutations in the gene for ASPA result in the fatal leukodystrophy Canavan disease, for which there is currently no effective treatment. Once postnatal myelination is completed, NAA may continue to be involved in myelin lipid turnover in adults, but it also appears to adopt other roles, including a bioenergetic role in neuronal mitochondria. NAA and ATP metabolism appear to be linked indirectly, whereby acetylation of aspartate may facilitate its removal from neuronal mitochondria, thus favoring conversion of glutamate to alpha ketoglutarate which can enter the tricarboxylic acid cycle for energy production. In its role as a mechanism for enhancing mitochondrial energy production from glutamate, NAA is in a key position to act as a magnetic resonance spectroscopy marker for neuronal health, viability and number. Evidence suggests that NAA is a direct precursor for the enzymatic synthesis of the neuron specific dipeptide N-acetylaspartylglutamate, the most concentrated neuropeptide in the human brain. Other proposed roles for NAA include neuronal osmoregulation and axon-glial signaling. We propose that NAA may also be involved in brain nitrogen balance. Further research will be required to more fully understand the biochemical functions served by NAA in CNS development and activity, and additional functions are likely to be discovered.     

头部亚低温治疗新生儿缺氧缺血性脑病的疗效及其对脑脊液中肌酸激酶脑型同工酶的影响

目的:探讨头部亚低温治疗对新生儿缺氧缺血性脑病(HIE)脑脊液中肌酸激酶脑型同工酶(CK鄄BB)的影响及临床治疗效果。 方法:选择 2014 年 3 月至 2016 年 3 月在我院治疗的 HIE 患儿 84 例,随机分为亚低温组 39 例和常规治疗组 45 例,亚低温组在常规治疗基础上给予头部亚低温治疗,常规治疗组给予 HIE 常规治疗,检测两组患儿脑脊液中 CK鄄BB 变化,同时进行新生儿神经行为(NBNA)评分和婴幼儿期智能发育评估。 结果:亚低温组和常规治疗组患儿治疗 72 h 后脑脊液中 CK鄄BB 较治疗前降低(P<0.05);亚低温组治疗72 h 后脑脊液中 CK-BB 为(13.10±1.57)U/ L,明显低于常规治疗组(P<0.05);两组出生14 d、28 d 时 NBNA 评分均较出生 7 d 时明显升高(P<0.05);亚低温组出生14 d 和28 d 时 NBNA 评分为(37.10±1.32)分和(38.10±1.30)分,均明显高于常规治疗组(P<0.05);亚低温组出生后 3 个月和 6 个月智力发育指数(MDI)分别为(91.02±9.80)分和(99.10±7.53)分,明显高于常规治疗组(P<0.05);亚低温组出生后 3 个月和 6 个月心理运动发育指数(PDI)分别为(87.22±6.72)分和(95.10±5.52)分,明显高于常规治疗组(P<0.05)。 结论:头部亚低温治疗 HIE 有较好的效果,能明显降低患儿脑脊液中 CK-BB 水平,值得临床推广。     

新生儿窒息后血清CK-MB、CT-1及H-FABP判断心肌损伤的价值

目的 探讨新生儿窒息后血清肌酸激酶同工酶（CK-MB）、心肌营养素-1（CT-1）及心性脂肪酸结合蛋白（H-FABP）判断心肌损伤的价值。方法 选取2018年1月～2019年12月我院收治的窒息新生儿98例为观察组,其中有心肌损伤者31例,同时选取健康新生儿50例为对照组,比较两组患儿血清CK-MB、CT-1及H-FABP水平。结果 两组性别、胎龄、体质量及身长比较差异无统计学意义（P＞0.05）;观察组出生后5 min Apgar评分（5.30±0.82）明显低于对照组（9.40±0.32）（P＜0.05）。观察组血清CK-MB、CT-1及H-FABP分别为（6.62±1.31）ng/mL、（68.46±18.84）ng/L和（21.03±8.11）ng/mL,明显高于对照组（P＜0.05）;观察组有心肌损伤患儿血清CK-MB、CT-1及H-FABP分别为（7.01±1.22）ng/mL、（78.11±12.03）ng/L和（30.45±9.54）ng/mL,明显高于无心肌损伤患儿（P＜0.05）;血清CK-MB、CT-1及H-FABP判断心肌损伤的ROC曲线下面积分别为0.629、0.815和0.862,其中CT-1及H-FABP的ROC曲线下面积高于CK-MB（均P＜0.05）。结论 CK-MB、CF-1及H-FABP在判断新生儿窒息后心肌损伤中有一定应用价值,其中CF1及HFABP价值较高。     

Effect of lansoprazole on DNA integrity of human spermatozoa and activity of seminal creatine kinase

Although lansoprazole (brand name Prevacid) is a commonly used dug to manage various acid-related gastrointestinal diseases, little is known about its effects on human semen quality and sperm parameters. Here, we aimed to investigate the effect of lansoprazole on DNA integrity of human spermatozoa and activity of seminal creatine kinase. DNA integrity of human spermatozoa was assessed by the Apo-Direct™ kit followed by flow cytometry. The activity of creatine kinase was measured by kinetic spectrophotometric method using commercially available kits following the International Federation of Clinical Chemistry recommendations. Lansoprazole at 3 µg/ml, after 1-hr incubation period, did not show any significant increase in fluorescein isothiocyanate fluorescence (p > .05) and hence on the content of DNA breaks of human spermatozoa. In addition, there was no significant change (p = .8113) in the activity of seminal creatine kinase by the effect of lansoprazole. In conclusion, lansoprazole at 3 µg/ml did not alter DNA integrity of human spermatozoa or activity of seminal creatine kinase after 1-hr incubation period.