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1.

Background

Glutamate plays a key role for post-ischaemic recovery of myocardial metabolism. According to post hoc analyses of the two GLUTAMICS trials, patients without diabetes benefit from glutamate with less myocardial dysfunction after coronary artery bypass surgery (CABG). Copeptin reflects activation of the Arginine Vasopressin system and is a reliable marker of heart failure but available studies in cardiac surgery are limited. We investigated whether glutamate infusion is associated with reduced postoperative rises of plasma Copeptin (p-Copeptin) after CABG.

Methods

A prespecified randomised double-blind substudy of GLUTAMICS II. Patients had left ventricular ejection fraction ≤0.30 or EuroSCORE II ≥3.0 and underwent CABG ± valve procedure. Intravenous infusion of 0.125 M L-glutamic acid or saline at 1.65 mL/kg/h was commenced 10–20 min before the release of the aortic cross-clamp and then continued for another 150 min P-Copeptin was measured preoperatively and postoperatively on day one (POD1) and day three. The primary endpoint was an increase in p-Copeptin from the preoperative level to POD1. Postoperative stroke ≤24 h and mortality ≤30 days were safety outcomes.

Results

We included 181 patients of whom 48% had diabetes. The incidence of postoperative mortality ≤30 days (0% vs. 2.1%; p = .50) and stroke ≤24 h (0% vs. 3.2%; p = .25) did not differ between the glutamate group and controls. P-Copeptin increased postoperatively with the highest values recorded on POD1 without significant inter-group differences. Among patients without diabetes, p-Copeptin did not differ preoperatively but postoperative rise from preoperative level to POD1 was significantly reduced in the glutamate group (73 ± 66 vs. 115 ± 102 pmol/L; p = .02). P-Copeptin was significantly lower in the Glutamate group on POD1 (p = .02) and POD 3 (p = .02).

Conclusions

Glutamate did not reduce rises of p-Copeptin significantly after moderate to high-risk CABG. However, glutamate was associated with reduced rises of p-Copeptin among patients without diabetes. These results agree with previous observations suggesting that glutamate mitigates myocardial dysfunction after CABG in patients without diabetes. Given the exploratory nature of these findings, they need to be confirmed in future studies.  相似文献   
2.
【目的】观察荷芪散治疗痰瘀互结证2型糖尿病(T2DM)合并冠心病(CHD)的临床疗效及其对血清氧化三甲胺(TMAO)水平的影响。【方法】将40例痰瘀互结证T2DM合并CHD患者随机分为观察组和对照组,每组各20例。2组患者均给予降压、调脂及抗血小板聚集等西医基础治疗,在此基础上,对照组给予利拉鲁肽治疗,观察组在对照组的基础上加用荷芪散治疗,疗程为1个月。观察2组患者治疗前后中医证候积分、糖代谢指标、脂代谢指标、左心室功能相关指标、炎症因子、内皮素1(ET-1)以及肠道菌群代谢产物TMAO水平的变化情况,并评价2组患者的临床疗效和安全性。【结果】(1)疗效方面:治疗1个月后,观察组的总有效率为95.0%(19/20),对照组为70.0%(14/20),组间比较,观察组的临床疗效明显优于对照组(P<0.05)。(2)中医证候积分方面:治疗后,2组患者的中医证候积分均较治疗前明显下降(P<0.01),且观察组对中医证候积分的下降作用明显优于对照组(P<0.01)。(3)糖代谢相关指标方面:治疗后,2组患者的空腹血糖(FPG)、餐后2 h血糖(2hPG)、糖化血红蛋白(HbA1c)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)均较治疗前明显下降(P<0.01),且观察组对FPG、2hPG、HbAlc、FINS、HOMA-IR的下降作用均明显优于对照组(P<0.05或P<0.01)。(4)脂代谢相关指标方面:治疗后,2组患者总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)均较治疗前明显下降(P<0.01),且观察组对TC、TG和LDL-C的下降作用均明显优于对照组(P<0.05)。(5)炎性因子、血管内皮因子以及肠道菌群代谢产物方面:治疗后,2组患者血清白细胞介素6(IL-6)、超敏C反应蛋白(hs-CRP)、ET-1和TMAO水平均较治疗前明显下降(P<0.01),且观察组对血清IL-6、hs-CRP、ET-1和TMAO水平的下降作用均明显优于对照组(P<0.05)。(6)超声心动图方面:治疗后,2组患者的左室射血分数(LVEF)、二尖瓣口血流频谱E峰与A峰流速比值(E/A)均较治疗前升高(P<0.01),且观察组对LVEF、E/A的升高作用均明显优于对照组(P<0.05)。(7)治疗过程中,2组患者均未出现相关并发症及药物不良反应。【结论】荷芪散联合利拉鲁肽治疗痰瘀互结证T2DM合并CHD患者,可以提高临床疗效,降低中医证候积分,改善糖脂代谢和胰岛素抵抗,提高左心室功能,降低炎症因子以及ET-1的表达,并降低血清TMAO水平,其疗效优于单用利拉鲁肽治疗。  相似文献   
3.
目的探讨脂蛋白a[Lp(a)]联合单核细胞/高密度脂蛋白胆固醇(HDL-C)比值(MHR)在非ST段抬高型急性冠脉综合征(NSTE-ACS)患者冠状动脉(冠脉)病变严重程度及预后中的评估及其价值。方法选择2020年3月至2021年3月安徽医科大学第一附属医院符合纳入标准的NSTE-ACS患者(n=310),依据冠脉造影结果进行Gensini评分,以Gensini积分的第3四分位数(QU=38)为切点,分为高危组(QU≥38,n=74)和非高危组(QU<38,n=236),比较其一般资料,并使用Logistic回归分析Lp(a)、MHR与冠脉病变严重程度的相关性;使用ROC曲线评估Lp(a)联合MHR评估冠脉病变严重程度及预后的价值。结果高危组和非高危组患者性别、吸烟史、高血压病、糖尿病、高胆固醇血症、肾功能不全等病史、他汀药物应用发生率差异无统计学意义(P>0.05),但高危组患者年龄、血Lp(a)水平和MHR均显著高于非高危组(P<0.01)。Spearman相关分析发现,Lp(a)和MHR分别与Gensini评分呈正相关(r=0.316,P<0.05;r=0.715,P<0.05)。Logistic多因素二元回归分析示,Lp(a)、年龄和MHR是冠脉高危病变的独立危险因素(P<0.01,P<0.05)。ROC曲线分析示,Lp(a)和MHR联合检测对冠脉高危病变评估的AUC(0.854),分别大于Lp(a)和MHR单独检测的AUC(0.852、0.754);联合评估的敏感度73.0%,高于单独检测Lp(a)的55.6%,但低于MHR的82.4%;联合评估的特异度85.6%,高于Lp(a)及MHR单独检测(84.1%、61.9%)。ROC曲线分析示,Lp(a)和MHR联合对NSTE-ACS患者不良预后评估的AUC(0.800),分别大于Lp(a)和MHR单独检测的AUC(0.781、0.739);联合评估患者预后的敏感度为72.2%,高于Lp(a)及MHR单独检测(66.7%、66.7%);联合评估的特异度为81.9%,高于MHR单独检测的80.9%,但低于Lp(a)单独检测的84.8%。结论异常升高的血Lp(a)水平联合MHR对NSTE-ACS患者冠脉病变的严重程度和不良预后具有较高的判断价值。  相似文献   
4.
目的:应用扫频光学相干断层扫描血管成像(SS-OCTA)对比研究白内障术中不同眼内压患者手术前后黄斑区血流的变化情况,为白内障个性化手术参数设计提供临床参考。

方法:前瞻性随机对照研究。收集2021-01/04于四川省人民医院住院行白内障手术的患者61例77眼,使用随机数字表分为A组(37眼)和B组(40眼),术中分别予以75、90cm灌注瓶瓶高,相当于55.5、66.6mmHg术中平均眼内压。所有患者除常规眼科检查外,术前、术后1、7、30d均行黄斑区SS-OCTA检查,观察黄斑区视网膜厚度及放射状毛细血管网(RPCP)层、浅层血管网(SVP)层、中层血管网(IVP)层、深层血管网(DVP)层灌注面积和血管密度。

结果:手术前后各时间点两组患者最佳矫正视力(BCVA)、眼压、黄斑中心凹无血管区(FAZ)面积、黄斑区视网膜厚度及各层灌注面积和血管密度均无组间差异性(均P>0.05),但均有时间差异性(均P<0.05),两组患者术后各时间点BCVA均较术前明显改善,眼压和FAZ面积均较术前下降(均P<0.05),黄斑区视网膜厚度及各层灌注面积和血流密度均较术前增加。

结论:白内障术后黄斑区视网膜厚度及各层血流密度和灌注面积均增加,FAZ面积下降,有助于促进术后视力的恢复,且术中选择55.5、66.6mmHg不同眼内压情况下,患者术后眼底血流改变情况无明显差异,故术中可以灵活选择眼内压,为患者提供个性化手术设计方案。  相似文献   

5.
ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established.  相似文献   
6.
7.
The Extracellular Vesicle Flow Cytometry Working Group ( http://www.evflowcytometry.org ) is formed by members of the International Society for Extracellular Vesicles (ISEV), the International Society for Advancement of Cytometry (ISAC), and the International Society on Thrombosis and Haemostasis (ISTH). This working group of flow cytometry experts develops guidelines for best practices regarding flow cytometry detection of extracellular vesicles. To improve rigor and standardization, this working group published a framework outlining the minimal information to report about a flow cytometry experiment on extracellular vesicles (MIFlowCyt-EV) in the Journal of Extracellular Vesicles, the ISEV journal, in 2020. In parallel, an article explaining MIFlowCyt-EV was published in Cytometry Part A, one of the ISAC journals, and now will be introduced to the ISTH as an SSC Communication in the Journal of Thrombosis and Haemostasis. The goal of this SSC Communication is to explain why flow cytometry is becoming the instrument of choice to characterize single extracellular vesicles, the obstacles that have been identified and (mostly) overcome by developing procedures to calibrate flow cytometers, and the relevance of reporting minimal information to improve reliability and reproducibility of experiments in which flow cytometers are used for characterization of extracellular vesicles.  相似文献   
8.
目的:探讨急性冠脉综合征(ACS)患者血清中促炎性因子血管生成素样蛋白-2(Angptl-2)的表达及其临床意义。方法:采用酶联免疫吸附方法(ELISA)检测182例ACS患者和30例对照组血清中Angptl-2、白细胞介素-6(IL-6)及可溶性细胞间黏附分子-1(sICAM-1)水平,通过受试者工作特征曲线(ROC)分析血清Angptl-2水平对ACS的诊断价值。人重组Angptl-2蛋白干预人冠状动脉内皮细胞(HCAEC)后,采用蛋白印迹法检测内皮细胞IL-6及ICAM-1的表达。结果:ACS患者血清中Angptl-2、IL-6及sICAM-1水平均明显高于对照组(P<0.001),且急性心肌梗死患者显著高于不稳定型心绞痛患者(P<0.05)。ROC曲线分析提示Angptl-2水平对ACS具有良好的诊断价值(曲线下面积为0.970),最佳诊断界值为5.77 ng/mL(敏感度为91.8%,特异度为93.3%,P<0.001)。人重组Angptl-2蛋白干预HCAEC后,内皮细胞IL-6及ICAM-1蛋白表达均上调(P<0.05)。结论:Angptl-2促进内皮细胞炎性黏附分子表达,其血清水平可作为ACS的诊断标志物。  相似文献   
9.
ObjectiveTo determine the long-term cardiovascular disease risk of astronauts with spaceflight exposure compared with a well-matched cohort.MethodsNational Aeronautics and Space Administration (NASA) astronauts are selected into their profession based upon education, unique skills, and health and are exposed to cardiovascular disease risk factors during spaceflight. The Cooper Center Longitudinal Study (CCLS) is a generally healthy cohort from a preventive medicine clinic in Dallas, Texas. Using a matched cohort design, astronauts who were selected beginning April 1, 1959, (and each subsequent selection class through 2009) and exposed to spaceflight were matched to CCLS participants who met astronaut selection criteria; 1514 CCLS participants matched to 303 astronauts in a 5-to-1 ratio on sex, date of birth, and age. The outcome of cardiovascular mortality through December 31, 2016, was determined by death certificate or National Death Index.ResultsThere were 11 deaths caused by cardiovascular disease (CVD) among astronauts and 46 among CCLS participants. There was no evidence of increased mortality risk in astronauts (hazard ratio [HR]=1.10; 95% confidence interval [CI], 0.50 to 2.45) with adjustment for baseline cardiovascular covariates. However, the secondary outcome of CVD events showed an increased adjusted risk in astronauts (HR=2.41; 95% CI, 1.26 to 4.63).ConclusionNo increased risk of CVD mortality was observed in astronauts with spaceflight exposure compared with a well-matched cohort, but there was evidence of increased total CVD events. Given that the duration of spaceflight will increase, particularly on missions to Mars, continued surveillance and mitigation of CVD risk is needed to ensure the safety of those who venture into space.  相似文献   
10.
目的建立小鼠肠道(包括小肠和结肠)黏膜固有层3型固有淋巴样细胞(ILC3)检测与分析的方法。方法小鼠麻醉后分离小肠和结肠组织,利用不同的消化液分别获得小肠和结肠固有层淋巴细胞悬液,通过CD45+CD3-CD90.2+RORγt+流式分析策略检测ILC3比例,通过IL-23刺激后用流式细胞术分析显示ILC3的IL-22表达水平。结果小肠和结肠固有层淋巴细胞成功分离,流式细胞术检测显示ILC3细胞分群显著并明显表达IL-22。在小肠和结肠中,ILC3在淋巴细胞中的占比分别为(8.30±2.42)%和(1.43±0.34)%,IL-22+ILC3在RORγt+ILC3中的占比分别为(38.98±8.76)%和(85.86±1.72)%。结论本研究成功建立了小鼠小肠和结肠黏膜固有层ILC3的检测和分析方法,为相关研究奠定了技术基础。  相似文献   
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