Effect of age on left ventricular systolic function in humans: a study of systolic isovolumic acceleration rate

The aim of this study was to examine the effect of age on left ventricular (LV) systolic function in normal healthy adults. Eighty consecutive subjects without cardiovascular disease underwent standard and tissue Doppler (TD) echocardiographic imaging. LV systolic function was assessed by load-dependent indices as ejection fraction (EF) and myocardial systolic velocities by TD as well as by the load-independent index, systolic isovolumic acceleration rate (IVA). None of the echocardiographic measurements of systolic function declined with age (mean IVA for the group, 286 +/- 123 cm s(-2); IVA vs. age, r = 0.21, P = 0.1). Likewise, LV end diastolic dimension, wall thickness, mass and left atrial maximum volume were not significantly related to age. On the other hand, as previously reported, echocardiographic indices of diastolic function showed a significant decline with age (P < 0.05). When the group was stratified by gender, isovolumic velocity and acceleration were higher in men than women, but the differences were not significant (P = 0.12 and 0.37, respectively). No significant relation was observed between age and measurements of LV systolic function by regression analysis in women (P > 0.1). However, in men, a positive correlation was noted between average IVA and age (r = 0.63, P = 0.007). In conclusion, age is not associated with a change in cardiac structure and LV systolic function, but is accompanied by a decline in echocardiographic indices of diastolic function. With respect to gender, age does not appear to influence LV systolic function in women, but is associated with an increase in IVA and septal systolic ejection in men.     

金丝桃抗脂质过氧化作用研究

为研究金丝桃的抗脂质过氧化作用,用分光光度法测定了金丝桃提取物对大鼠离体组织匀浆的脂质过氧化及由Fe2+-H2O2体系、Fe2+-VitC体系和Fe2+-Cys体系诱导的脂质过氧化的抑制作用。发现金丝桃提取物对大鼠肝、心、肾组织匀浆脂质过氧化和线粒体诱导的脂质过氧化具有抑制作用并表现出剂量依赖关系,而且提取物F003的抑制作用要强于F004、F005的抑制作用。认为金丝桃具有较好的抗脂质过氧化作用,具有进一步研究与开发价值。     

Probucol improves erectile function by regulating endoplasmic reticulum stress in rats with streptozotocin-induced diabetes

This study was to explore the effect and mechanism of Probucol on STZ-induced erectile dysfunction in diabetic rats. Thirty SD male rats aged 12 weeks were given intraperitoneal injection of STZ after fasting for 12 hr. Diabetic rats were haphazardly partitioned under two assemblies and administered 0 or 500 mg/kg probucol by oral gavage to 12 weeks. Control group was intraperitoneally injected with physiological saline, and saline was administered by oral gavage daily. Intracorporeal pressure was used to evaluate erectile function. Levels of proteins were detected using immunohistochemistry and Western blotting. α-SMA and vWF were detected using immunofluorescence staining. After treatment, erectile function in probucol group was significantly improved. Endoplasmic reticulum stress-related proteins were expressed higher in DM group than in sham group, while expression of these proteins decreased significantly in probucol group. However, α-SMA and vWF were expressed at lower levels in DM group than in sham group, and probucol treatment reversed this phenomenon. Finally, Bax and Caspase3 were expressed at higher levels and Bcl-2 was expressed at lower levels in DM group, while the opposite result was obtained in probucol group. In conclusions, probucol improves erectile function by reducing endothelial dysfunction and inhibiting PERK/ATF4/CHOP pathway in STZ-induced diabetic rats.     

Targeting NF-κB c-Rel in regulatory T cells to treat corneal transplantation rejection

The relevance of Tregs in the induction of tolerance against corneal allografts has been well established. Although it is well known that the conversion of Tregs into effector-like cells contributes to the loss of corneal immune privilege, the underlying mechanism is still not fully understood. Using heterologous penetrating keratoplasty model, we found that Tregs from corneal allograft rejected mice (inflam-Tregs) exhibit impaired function and characteristics of effector T cells. Further study showed that the expression of NF-κB c-Rel, a key mediator of effector T cell function, was significantly increased in inflam-Tregs. Mechanistic study revealed that elevated NF-κB c-Rel level in inflam-Tregs impaired Treg function through the promotion of inflammatory cytokine production and glycolysis. More importantly, we demonstrated that targeting NF-κB c-Rel was able to improve the immune suppressive function of inflam-Tregs in vitro and enhance the potential of them to suppress corneal transplantation rejection. Therefore, our current study identified NF-κB c-Rel as a key mediator of the conversion of Tregs into effector-like cells when under inflammatory environment.     

Value of preoperative urine white blood cell and nitrite in predicting postoperative infection following percutaneous nephrolithotomy: a meta-analysis

BackgroundTo evaluate to what degree preoperative urine white blood cell (WBC) and urine nitrite (NIT) values are predictive of postoperative infections following percutaneous nephrolithotomy (PCNL).MethodsA systematic literature search was performed of the PubMed, Embase, Cochrane Library, Wanfang Data, National Knowledge Infrastructure (CNKI), and China Science and Technology Journal Database (CSTJ or VIP) online databases to identify relevant studies that examined the predictive value of urine WBC or NIT as risk factors for post-PCNL infection, and the search was finished on February 28, 2020. Two independent reviewers screened the relevant studies, extracted necessary data from the eligible case-control studies (CCS), and assessed the quality of included studies through the Newcastle-Ottawa scale (NOS). RevMan 5.3 software and the Stata 16.0 software were used to complete the statistical analysis of data. Results are expressed as odds ratio (OR) with 95% confidence intervals (CIs).ResultsAccording to the statistical analysis of 12 eligible studies involving 6113 patients, positive urine WBC (WBC+: OR =3.86, 95% CI: 3.03–4.91, P<0.001) and positive NIT (NIT⁺: OR =7.81, 95% CI: 5.44–11.21, P<0.001) in preoperative tests were identified as independent risk factors for postoperative infections following PCNL.ConclusionsIn summary, as risk factors for postoperative infections, the presence of preoperative urine WBC+ and NIT+ should be evaluated as part of clinical procedure, in order to reduce infections of PCNL.     

积分加权法评价磷化学烧伤实验病理的意义与应用

目的：积分加权法在病理组织学检查中的应用，方法：在常规病理描述基础上，采用积分加权法将病理结果予以定量，综合评价致伤后实验动物的主要脏器，结果：实验动物同等面积的磷酸烧伤各脏器积分降低，钙治疗后则显著改善，均与其它方面报道的资料一致，结论：积分加以数值使各脏器损伤程度一目了然，对不同脏器间的损伤情况有可比性，从而有助于了解主要受损脏器与总体的关系以及药物的治疗效果。     

基于直方图拟合的MRI图像水平集分割

利用混合高斯模型对MRI图像直方图进行分析,将拟合获得的特征参数作为水平集曲线进化的约束条件,对医学图像进行分割。分割中采用的自适应Level Set方法,能够自适应地确定曲线进化方向（扩张或收缩）,而不必在分割之前指定其进化方向,减少了人工干预;同时也克服了传统测地活动轮廓线（GAC）方法对图像梯度信息的过分依赖,以及由于对图像进行大尺度高斯平滑处理造成边缘点移动、定位准确度下降的缺陷。分别对MRI仿真和真实图像进行了实验,MRI仿真实验的分割敏感性、专一性和总体性能指标分别达到了94.72%、97.52%和97.22%。分割结果的定量分析和定性分析表明算法的有效性以及较高的分割准确度。     

几丁糖预防屈肌腱粘连的临床效果

目的：观察几丁糖预防肌腱粘连的临床效果。方法：对Ⅱ区肌腱损伤４８例７２条肌腱断裂行一期修复,术中采用改良Ｋｅｓｓｌｅｒ法缝合肌腱,在肌腱鞘管内注入２％医用几丁糖０．５￣１．０ｍｌ,缝合皮肤。     

急性心肌缺血时锌铜含量的变化及影响

目的　探讨急性心肌缺血时锌铜含量的变化及影响。方法　分别测定急性心肌缺血家兔局部心肌、心血、外周血及 15 0例急性心肌缺血病人血清中锌铜含量 ,并与对照组比较。腹腔给予急性心肌缺血家兔补充锌铜溶液 ,观察给予前后ECG变化。结果　家兔随心肌缺血时间延长 ,锌铜含量在局部心肌中逐渐减少 ,心血及外周血中逐渐增加 ,与对照组比差异显著 (P <0 .0 5 ) ;急性心肌缺血病人血清锌铜含量明显降低 (P <0 .0 1) ;家兔腹腔给予锌铜溶液心肌缺血及心律失常明显好转。结论　急性心肌缺血早期锌铜含量变化能引起心电活动的改变 ,可能是猝死的原因之一。补充锌铜对纠正心律失常及心肌缺血有一定作用。