Liguzinediol对阿霉素诱导的慢性心衰大鼠心功能的影响

目的 通过阿霉素（Dox）复制大鼠慢性心力衰竭（CHF）模型，观察Liguzinediol对CHF大鼠心功能的影响。方法 通过血流动力学观察Liguzinediol对Dox（腹腔注射，2 mg/kg）诱导的CHF大鼠左心室内压最大上升/下降速率(±dp/dt_max)、左心室内压(LVSP)、动脉收缩压(ASP)、动脉舒张压(ADP)和心率(HR)的变化；观察Liguzinediol对血清一氧化氮（NO）、一氧化氮合成酶（NOS）、超氧化物歧化酶（SOD）、肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）以及血浆中丙二醛（MDA）的影响。结果 Liguzinediol能增加LVSP、+dp/dt_max、ASP、ADP、AP、HR，降低-dp/dt_max(P<0.05~0.01)；降低NO、iNOS以及MDA的浓度，同时增强了SOD的活性(P<0.05~0.01)；抑制IL-6和TNF-α的生成(P<0.05~0.01)。结论 Liguzinediol可明显改善Dox诱导的CHF大鼠血流动力学指标，减少模型大鼠炎症因子的释放以及抑制氧自由基的生成。      

Associations between heart rate variability and maximal fat oxidation in two different cohorts of healthy sedentary adults

Background and aimsResting heart rate variability (HRV) and maximal fat oxidation (MFO) during exercise are both considered as a noninvasive biomarkers for early detection of cardiovascular risk factors. Thus, this study aimed to analyze the relationship between resting HRV parameters and MFO during exercise, and the intensity of exercise that elicit MFO (Fat_max) in healthy sedentary adults.Methods and resultsA total of 103 healthy young adults (22.2 ± 2.3 years old, 67% female; from the ACTIBATE cohort) and 67 healthy middle-aged adults (53.1 ± 5.0 years old, 52% female; from the FIT-AGEING cohort) were included in this cross-sectional study. HRV was assessed using a Polar RS800CX heart rate monitor, while MFO and Fat_max were determined during a graded exercise treadmill test using indirect calorimetry. No significant associations were observed for healthy young adults (standardized β coefficients ranged from ?0.063 to 0.094, and all P ≥ 0.347) and for middle-aged adults (standardized β coefficients ranged from ?0.234 to 0.090, and all P ≥ 0.056). Nevertheless, only a weak association was observed between one HRV parameter in time-domain (the percentage of R-R intervals that shows a difference higher than 50 ms [pNN50]) and MFO in the cohort of middle-aged adults (β coefficient = ?0.279, and P = 0.033).ConclusionThe results of this study suggest that resting HRV parameters are not associated with MFO and Fat_max during exercise in two independent cohorts of healthy sedentary young and middle-aged adults, respectively.     

On estimands arising from misspecified semiparametric rate-based analysis of recurrent episodic conditions

Marginal rate-based analyses are widely used for the analysis of recurrent events in clinical trials. In many areas of application, the events are not instantaneous but rather signal the onset of a symptomatic episode representing a recurrent infection, respiratory exacerbation, or bout of acute depression. In rate-based analyses, it is unclear how to best handle the time during which individuals are experiencing symptoms and hence are not at risk. We derive the limiting value of the Nelson-Aalen estimator and estimators of the regression coefficients under a semiparametric rate-based model in terms of an underlying two-state process. We investigate the impact of the distribution of the episode durations, heterogeneity, and dependence on the asymptotic and finite sample properties of standard estimators. We also consider the impact of these features on power in trials designed to test intervention effects on rate functions. An application to a trial of individuals with herpes simplex virus is given for illustration.     

Outcomes of coronary artery bypass grafting in patients with heart failure with a midrange ejection fraction

BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization.     

二补助育汤对胚胎着床障碍小鼠子宫血管生成相关因子表达的影响

目的：探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1（Ang-1）mRNA、血管内皮生长因子（VEGF）mRNA的表达和定位的影响。方法：24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组，每组6只，用米非司酮建立胚胎着床障碍动物模型，各组给予相应药物灌胃，妊娠第5天处死小鼠后，检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果：模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组（均P<0.05）；与模型组比较，二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高（均P<0.05）。结论：二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量，促进子宫内膜血管生成，从而提高子宫内膜容受性。     

Cardioprotective effects of sinomenine in myocardial ischemia/reperfusion injury in a rat model

BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.