人工髋关节置换术发生股骨假体周围骨折的影响因素分析

目的:探讨人工髋关节置换术患者发生股骨假体周围骨折的相关危险因素,为临床预防和治疗提供参考资料。方法:回顾性分析2012年5月~2015年5月在我院接受人工髋关节置换术的92例患者的临床资料。根据是否发生股骨假体周围骨折将所选患者分为研究组和对照组,每组46例,比较两组患者的性别分布、年龄、骨折类型及假体固定方式等,分析影响患者发生股骨假体周围骨折的危险因素。结果:研究组患者骨折类型多为A2型,患者平均年龄、女性患者数及使用生物假体的比例均高于对照组,差异具有统计学意义(P0.05)。患者性别、年龄、骨折类型及假体固定方式是人工髋关节置换术患者发生股骨假体周围骨折的危险因素(OR=1.993、2.012和2.363,P0.05)。结论:高龄女性患者是发生股骨周围假体骨折的高危人群,骨质疏松及骨量减少是引发该并发症的主要危险因素。     

育肥饲料中植物油混合替代鱼油对中华绒螯蟹雄体脂肪酸代谢相关基因表达的影响

为研究植物油替代鱼油对中华绒螯蟹(以下简称河蟹)脂肪酸代谢产生的影响, 通过荧光定量PCR (qRTPCR)技术研究了河蟹脂肪酸碳链延长酶(Es-FAE)、9脂肪酸去饱和酶(Es-FAD9)、6脂肪酸去饱和酶b (Es-FAD6b)、脂肪酸结合蛋白3 (Es-FABP3)、脂肪酸结合蛋白9 (Es-FABP9)和脂肪酸结合蛋白10 (Es-FABP10)基因在不同组织中的表达情况, 以及育肥饲料中不同鱼油替代水平(鱼油替代水平分别为0、25%、50%、75%和100%, 记为饲料1#5#组)对河蟹雄体肝胰腺中这些基因mRNA表达水平的影响, 以探讨育肥中鱼油替代对河蟹雄体成蟹脂肪酸代谢的影响。结果表明: (1) Es-FAE、Es-FAD6b和Es-FAD9均在肝胰腺中表达水平最高, 在心脏和血淋巴中表达水平较低, 不同基因在其他组织中的表达规律有所不同; Es-FABP3、Es-FABP9和Es-FABP10主要在肝胰腺、肌肉、输精管和副性腺中表达水平较高, 在胃、肠和心脏中表达水平较低。(2) 随着饲料中鱼油替代水平的提高, 肝胰腺中Es-FAE-mRNA有显著增加趋势; 就Es-FAD6b而言, 饲料3#组显著高于饲料2#组, 其余各组间差异不显著; 随着饲料中鱼油水平的降低, 饲料1#3#组肝胰腺中Es-FAD9-mRNA也有显著增加趋势, 但差异不显著。(3) 就Es-FABP3而言, 饲料2#和3#组肝胰腺中表达水平最高,且显著高于饲料1#组(P0.05), 其余各组间差异不显著; 随着鱼油替代水平的升高, 肝胰腺中Es-FABP9和Es-FABP10-mRNA水平均有先上升后下降趋势, 但各组间差异不显著。综上, 河蟹脂肪酸代谢和转运相关基因在肝胰腺中表达水平最高, 饲料中不同鱼油替代水平对肝胰腺中上述基因mRNA表达水平具有较大影响。     

Three-dimensional macro-scale assessment of regional and temporal wall shear stress characteristics on aortic valve leaflets

The aortic valve (AV) achieves unidirectional blood flow between the left ventricle and the aorta. Although hemodynamic stresses have been shown to regulate valvular biology, the native wall shear stress (WSS) experienced by AV leaflets remains largely unknown. The objective of this study was to quantify computationally the macro-scale leaflet WSS environment using fluid–structure interaction modeling. An arbitrary Lagrangian–Eulerian approach was implemented to predict valvular flow and leaflet dynamics in a three-dimensional AV geometry subjected to physiologic transvalvular pressure. Local WSS characteristics were quantified in terms of temporal shear magnitude (TSM), oscillatory shear index (OSI) and temporal shear gradient (TSG). The dominant radial WSS predicted on the leaflets exhibited high amplitude and unidirectionality on the ventricularis (TSM>7.50 dyn/cm², OSI < 0.17, TSG>325.54 dyn/cm² s) but low amplitude and bidirectionality on the fibrosa (TSM < 2.73 dyn/cm², OSI>0.38, TSG < 191.17 dyn/cm² s). The radial WSS component computed in the leaflet base, belly and tip demonstrated strong regional variability (ventricularis TSM: 7.50–22.32 dyn/cm², fibrosa TSM: 1.26–2.73 dyn/cm²). While the circumferential WSS exhibited similar spatially dependent magnitude (ventricularis TSM: 1.41–3.40 dyn/cm², fibrosa TSM: 0.42–0.76 dyn/cm²) and side-specific amplitude (ventricularis TSG: 101.73–184.43 dyn/cm² s, fibrosa TSG: 41.92–54.10 dyn/cm² s), its temporal variations were consistently bidirectional (OSI>0.25). This study provides new insights into the role played by leaflet–blood flow interactions in valvular function and critical hemodynamic stress data for the assessment of the hemodynamic theory of AV disease.     

经皮穴位电刺激对老年髋关节置换术患者脑氧代谢以及术后认知功能、镇痛效果的影响

目的:探讨经皮穴位电刺激(TEAS)对老年髋关节置换术患者脑氧代谢以及术后认知功能、镇痛效果的影响。方法:选取2016年1月～2018年7月期间我院收治的行髋关节置换术患者91例为研究对象,将研究对象根据随机数字表法分为对照组(n=45)和研究组(n=46),对照组给予常规麻醉处理,研究组在对照组基础上给予TEAS,比较两组脑氧代谢、术后认知功能以及镇痛效果,记录两组术后的不良反应发生情况。结果:在降压开始后20 min(T1)、降压开始后40 min(T2)、停止降压后20 min(T3)时间点时,两组静脉血氧含量(Cjv O2)较降压前即刻(T0)时间点升高,且研究组高于对照组(P0.05),两组脑动-静脉血氧含量差(Da-jvO2)、脑氧摄取率(CERO2)较T0时间点降低,且研究组低于对照组(P0.05)。两组患者术后72h简易智能量表(MMSE)评分均较术前24h降低,但研究组高于对照组(P0.05),研究组术后认知功能障碍(POCD)发生率低于对照组(P0.05)。与术前比较,两组患者术后8h、术后24h、术后48h视觉疼痛模拟量表(VAS)评分均升高(P0.05),但研究组术后8h、术后24h、术后48h等时间点VAS评分均低于对照组(P0.05)。两组患者不良反应总发生率比较无差异(P0.05)。结论:TEAS对老年髋关节置换术后患者的镇痛效果确切,可有效改善脑氧代谢情况,提高术后认知功能,临床应用价值较高。     

内固定与关节置换手术治疗骨质疏松性髋部骨折的临床效果及术后并发症的影响因素分析

目的:分析内固定与关节置换手术治疗骨质疏松性髋部骨折的临床效果及其术后并发症的影响因素。方法:将2017年4月至2018年5月因骨质疏松性髋部骨折于我院进行手术治疗的78例患者作为研究对象,参考患者自身意愿按照采取手术方案的不同将所有患者分为内固定组与关节置换组。内固定组主要采用动力髋螺钉内固定治疗;关节置换组采用全髋关节置换术治疗。对比分析两组治疗后并发症的发生情况及关节功能恢复程度。结果:关节置换组手术治疗后关节功能的恢复情况显著优于内固定组(P0.05),术后并发症发生率低于内固定组(P0.05);患者术后并发症发生的主要影响因素包括:术前存在合并症、手术时机≥2h、采用内固定手术。结论:与内固定术相比,关节置换手术治疗骨质疏松性髋部骨折患者的疗效和安全性均更高,但采用该手术治疗时需注意手术操作的规范性及手术时机。     

脓毒症急性肾损伤患者血液净化时机选择对治疗期间微循环系统的影响研究

目的:探究脓毒症急性肾损伤患者血液净化时机选择对治疗期间微循环系统的影响。方法:选取2016年2月～2017年2月期间来我院治疗的脓毒症急性肾损伤患者200例作为研究对象,依据急性肾损伤的诊断和分级(RIFLE)标准将脓毒症急性肾损伤患者分为1期(A组,n=56)、2期(B组,n=70)、3期(C组,n=74),所有患者皆采取连续性肾脏替代疗法。观察不同时期治疗前后微循环的变化。结果:三组脓毒症急性肾损伤患者在性别、年龄、空腹血糖浓度、急性生理功能和慢性健康状况(APACHE)评分、体温、心率指标上差异无统计学意义(P0.05);治疗后,A组患者微血管流动指数低于B组和C组,而灌注血管比例、灌注血管密度及总血管密度显著高于B组和C组(P0.05);A组患者血液流态积分、襻周状态积分、管襻形态积分及总积分显著低于B组和C组(P0.05),而襻顶血管直径显著大于B组和C组(P0.05)。结论:在RLFLE诊断标准1期对脓毒症急性肾损伤患者实施血液净化,可以明显地改善治疗效果,促进微循环系统的恢复。     

19-Hydroxyeicosatetraenoic acid analogs: Antagonism of 20-hydroxyeicosatetraenoic acid-induced vascular sensitization and hypertension

19-Hydroxyeicosatetraenoic acid (19-HETE, 1), a metabolically and chemically labile cytochrome P450 eicosanoid, has diverse biological activities including antagonism of the vasoconstrictor 20-hydroxyeicosatetraenoic acid (20-HETE, 2). A SAR study was conducted to develop robust analogs of 1 with improved in vitro and in vivo efficacy. Analogs were screened in vitro for inhibition of 20-HETE-induced sensitization of rat renal preglomerular microvessels toward phenylephrine and demonstrated to normalize the blood pressure of male Cyp4a14(-/-) mice that display androgen-driven, 20-HETE-dependent hypertension.     

Malate valves: old shuttles with new perspectives

Malate valves act as powerful systems for balancing the ATP/NAD(P)H ratio required in various subcellular compartments in plant cells. As components of malate valves, isoforms of malate dehydrogenases (MDHs) and dicarboxylate translocators catalyse the reversible interconversion of malate and oxaloacetate and their transport. Depending on the co‐enzyme specificity of the MDH isoforms, either NADH or NADPH can be transported indirectly. Arabidopsis thaliana possesses nine genes encoding MDH isoenzymes. Activities of NAD‐dependent MDHs have been detected in mitochondria, peroxisomes, cytosol and plastids. In addition, chloroplasts possess a NADP‐dependent MDH isoform. The NADP‐MDH as part of the ‘light malate valve’ plays an important role as a poising mechanism to adjust the ATP/NADPH ratio in the stroma. Its activity is strictly regulated by post‐translational redox‐modification mediated via the ferredoxin‐thioredoxin system and fine control via the NADP⁺/NADP(H) ratio, thereby maintaining redox homeostasis under changing conditions. In contrast, the plastid NAD‐MDH (‘dark malate valve’) is constitutively active and its lack leads to failure in early embryo development. While redox regulation of the main cytosolic MDH isoform has been shown, knowledge about regulation of the other two cytosolic MDHs as well as NAD‐MDH isoforms from peroxisomes and mitochondria is still lacking. Knockout mutants lacking the isoforms from chloroplasts, mitochondria and peroxisomes have been characterised, but not much is known about cytosolic NAD‐MDH isoforms and their role in planta. This review updates the current knowledge on MDH isoforms and the shuttle systems for intercompartmental dicarboxylate exchange, focusing on the various metabolic functions of these valves.     

Identification and characterization of cells with high angiogenic potential and transitional phenotype in calcific aortic valve

Recent data suggest that angiogenesis plays an important role in the pathogenesis of valvular disease. However, the cellular mechanisms underlying this process remain unknown. This study aimed at identifying and characterizing the cellular components responsible for pathological neovascularization in calcific aortic valves (CAV). Immunohistochemical analysis of uncultured CAV tissues revealed that smooth muscle alpha-actin (alpha-SMA)-positive cells, which coexpressed Tie-2 and vascular endothelial growth factor receptor-2 (VEGFR-2), can be identified prior to the initiation of capillary-like tube formation. In a second step, leaflets of CAV and non-calcific aortic valves (NCAV) were cultured and the cells involved in capillary-like tube formation were isolated. The majority of these cells displayed the same phenotype as non-cultured cells identified in CAV tissues, i.e., expression of alpha-SMA, Tie-2, and VEGFR-2. In comparison to cells isolated from cultures of NCAV leaflets, these cells showed enhanced angiogenic activity as demonstrated by migration and tube assays. The coexpression of VEGFR-2 and Tie-2 together with alpha-SMA suggests both endothelial and mesenchymal properties of the angiogenically activated cells involved in valvular neovascularization. Hence, our findings might provide new insights into the process of pathological angiogenesis in cardiac valves.