异丙酚混合氯胺酮对大鼠海马神经元钠电流的影响

目的研究异丙酚混合氯胺酮对大鼠海马神经元钠电流的影响。方法酶消化法急性分离SD大鼠(出生10～14 d)海马神经元,全细胞膜片钳技术记录不同浓度氯胺酮、异丙酚或异丙酚混合氯胺酮对海马神经元钠电流的影响。结果在钳制电压-80 mV、刺激电压0 mV条件下,5．6- 560μmol·L-1异丙酚对钠电流的抑制作用逐渐增加,其抑制钠电流的IC50为(44±4)μmol·L-1;0．18 mmol·L-1氯胺酮对钠电流没有影响,0．54、1．8、5．4、10．8 mmol·L-1氯胺酮对钠电流均有抑制作用,其抑制钠电流的IC50为(2．7±0．7)mmol·L-1。1/4和3/4 IC50的异丙酚与0．54、1．8、5．4、10．8 mmol·L-1氯胺酮混合应用抑制钠电流的IC50分别为1．14±0．21、(0．97±0．32)mmol·L-1,异丙酚与氯胺酮混合应用产生相加作用。结论异丙酚混合氯胺酮对抑制大鼠海马神经元钠电流产生相加作用。     

Identification of promotion and prevention associated surgeon behaviors in the operating room to facilitate resident self-regulated learning

BackgroundThe regulatory focus theory (RFT) posits that people can pursue goals with a promotion or prevention focus. Greater alignment of RFT motivational styles between faculty and residents may enhance resident operative autonomy. This study establishes a set of faculty behaviors residents can identify to infer faculty motivational styles.Methods10 behaviors associated with promotion and prevention motivational styles were identified. General surgery residents rated faculty on how strongly they exhibit these behaviors. Faculty conducted a self-assessment of how strongly they exhibit these behaviors.ResultsThere is a positive correlation between resident and faculty ratings for the promotion-associated behaviors of “works quickly,” “high energy,” and “mostly provides broad oversight,” and for the prevention-associated behaviors of “works slowly and deliberately,” “quiet and calm,” and “preference for vigilant strategies.”ConclusionResidents can observe faculty operative behaviors to infer faculty motivational styles. Residents may use this knowledge to adjust to faculty motivational styles and enhance operative interactions.     

低氧环境对椎间盘自发性吸收的影响及其作用机制

目的探讨低氧环境对椎间盘自发性吸收的影响及其作用机制。方法取SPF级成年日本大耳兔9只,雌雄不限,平均体质量2 kg。将兔处死后取脊柱髓核组织,经消化、分离、培养后获得传代髓核细胞,将生长良好的髓核细胞制成细胞悬液。根据不同时效的低氧环境将细胞分为5组对照组(常氧浓度下培养6 h)、低氧6 h组(2%O2浓度下培养6 h)、低氧12 h组(2%O2浓度下培养12 h)、低氧24 h组(2%O2浓度下培养24 h)和低氧48 h组(2%O2浓度下培养48 h)。采用实时聚合酶链反应法检测缺氧诱导因子(HIF)-1α、3型酸敏感离子通道(ASIC3)及水通道蛋白3(AQP3)mRNA表达水平,采用流式细胞仪检测各组髓核细胞凋亡情况。采用SPSS 24.0软件对数据进行分析。结果与对照组比较,低氧各组细胞凋亡率均明显升高,差异均有统计学意义(均P<0.01);与低氧12、24和48 h组比较,低氧6 h组细胞凋亡率最高,差异均有统计学意义(均P<0.01)。与对照组比较,低氧各组细胞HIF-1α和ASIC3 mRNA表达水平均明显上升,AQP3 mRNA表达水平均明显下降,差异均有统计学意义(均P<0.01);与低氧12、24和48 h组比较,低氧6 h组HIF-1α和ASIC3 mRNA表达水平最高,差异均有统计学意义(均P<0.01)。结论短时间低氧环境可以促进髓核细胞凋亡,从而加速椎间盘突出组织自发性吸收进程,其机制可能与HIF-1α和ASIC3的表达增加及AQP3的表达下降有关。     

粉防己碱舒张离体新西兰白兔阴茎海绵体平滑肌的机制研究

目的观察粉防己碱(tetrandrine,Tet)对阴茎海绵体平滑肌胞内钙释放和胞外钙内流的影响,初步探讨其舒张作用的机制。方法采用离体阴茎海绵体平滑肌肌条张力记录法,观察Tet对去氧肾上腺素(phenylephrine,PE)和氯化钾(KCI)诱导收缩的肌条的影响；采用无Ca~(2 )-复Ca~(2 )实验法,观察Tet对PE诱导的依赖细胞内钙和细胞外钙的肌条收缩反应的影响。结果Tet对PE或kcl诱导的肌条收缩均具有浓度依赖性的抑制作用。100μmol/L Tet可抑制20μmol/L PE引起的依赖细胞内钙和细胞外钙的肌条收缩(P＜0．05)；结论Tet可通过阻滞电压依赖性钙通道、受体依赖性钙通道和抑制细胞内钙库释放,从而介导其对海绵体平滑肌的舒张作用。     

Myocardial preconditioning against ischemia-induced apoptosis and necrosis in man

BACKGROUND: Ischemic preconditioning (IPC) protects against apoptosis and necrosis but the contribution of the two forms of cell death and whether the beneficial effects are mediated by similar or different signal transduction pathways remains unclear. Here we have investigated the effect of IPC on the type of cell death in the human heart and whether the inhibition of apoptosis and necrosis by IPC requires the opening of mitoK(ATP) channels and the activation of PKC and p38MAPK. MATERIALS AND METHODS AND RESULTS: Free-hand tissue sections (n = 6/group) obtained from the right atrium of patients at the time of coronary bypass surgery were subjected to 90-min simulated ischemia followed by 120-min reoxygenation (SI/R) with or without IPC (5 min SI/5 min R) prior to SI/R. IPC reduced apoptosis from 30.0 +/- 3.8 to 11.0 +/- 1.5% (P < 0.05) by TUNEL technique and necrosis from 11.6 +/- 2.4 to 4.2 +/- 1.7% (P < 0.05) by propidium iodide staining. When inhibitors of mitoKATP channels (1 mm 5-hydroxydecanoate), PKC (10 microm chelerythrine), and p38MAPK (10 microm SB203580) were added for 10 min before SI, the protection against necrosis was abolished. However, whereas 5-hydroxydecanoate and chelerythrine also abolished the protection of IPC against apoptosis, SB203580 did not. The activation of mitoKATP channels (100 microm diazoxide), PKC (1 microm PMA), and p38MAPK (1 nm anisomycin) were a mirror image of the findings with blockers. CONCLUSIONS: IPC protects the human myocardium against both apoptosis and necrosis. The anti-necrotic effect is mediated by the opening of mitoKATP channels and activation of PKC and p38MAPK; however, the anti-apoptotic effect requires opening of the mitoKATP channels and PKC activation but is p38MAPK-independent.     

TRPM7与肿瘤

瞬时受体电位(transient receptor potential,TRP)通道是位于细胞膜上的一类重要的阳离子通道超家族。TRPM(transient receptor potential melastatin)7是TRPM亚族的一员,是具有离子通道和激酶活性双功能的膜蛋白。它对阳离子有通透性,使细胞去极化,可使自身和底物磷酸化。TRPM7可以介导感觉信号的传递,调节细胞钙镁平衡和影响发育,其表达及活性异常与多种疾病特别是肿瘤的发生具有相关性。TRPM7通道激酶在细胞的增殖、存活、分化、生长和迁移等一系列细胞活动中起重要作用。     

2型糖尿病大鼠肠系膜动脉平滑肌细胞大电导钙激活钾通道α、β1亚基蛋白及mRNA表达水平变化

目的  探讨2型糖尿病（T2DM）大鼠肠系膜动脉平滑肌细胞大电导钙激活钾通道（BKCa）α、β1亚基蛋白及mRNA表达水平变化,从分子水平阐明T2DM大鼠肠系膜动脉平滑肌细胞膜BKCa通道活性改变的具体机制,为T2DM的综合治疗提供新靶点;为特异性针对此环节的药物研发提供实验依据。方法  SD大鼠高糖高脂饮食1个月后腹腔注射链脲菌素STZ（25 mg/kg）建立T2DM大鼠模型。免疫印记法和实时定量聚合酶链式反应测定肠系膜动脉BKCa通道α和β1亚基的蛋白和mRNA表达水平。结果  ①免疫印迹结果显示：模型组在第8周和第12周肠系膜动脉大电导钙激活钾通道（BKCa）α蛋白相对表达量分别为（1.093±0.251）和（0.921±0.153）,与对照组比较差异无统计学意义（P >0.05）;β1蛋白相对表达量分别为（0.334±0.200）和（0.193±0.310）,与对照组比较差异有统计学意义（P <0.05）。②实时定量聚合酶链式反应结果显示,模型组在第8周和第12周肠系膜动脉BKCa α亚基mRNA的表达分别为（1.15±0.03）和（0.92±0.04）,与对照组比较差异无统计学意义（P >0.05）;β1亚基mRNA的表达分别为（0.47±0.10）和（0.37±0.12）,与对照组比较差异有统计学意义（P <0.05）。结论  T2DM大鼠肠系膜动脉BKCa β1亚基蛋白和mRNA表达在8周及12周明显降低。

     

理筋通督手法治疗颈性眩晕临床研究

目的:观察理筋通督手法治疗颈性眩晕的临床疗效。方法:将120例颈性眩晕患者随机分成3组,理筋通督组、传统手法组及安慰剂组。理筋通督组采用理筋通督手法;传统手法组采用传统手法;安慰剂组口服维生素C。结果:理筋通督手法可显著减缓患者基底动脉舒张期最低血流速度(P0.05)。理筋通督组有效率为93.67%,传统手法组有效率为67.5%,安慰剂组有效率为17.5%,3组比较差异有统计学意义(P0.05),理筋通督组明显优于其他两组。结论:理筋通督手法治疗颈性眩晕临床疗效显著。     

糖尿病心肌细胞离子通道改变研究进展

越来越多的证据表明糖尿病会导致一种特异性心肌病——糖尿病心肌病(diabetic cardiomyopathy,DCM),其独立于其他心血管疾病.DCM患者易合并多种心律失常,发病率和死亡率很高,且心电图常显示QT间期延长.离子通道的改变是导致动作电位时程延长的基础,主要涉及钙离子、钾离子和钠离子通道的改变,本文对DCM患者离子通道改变的相关研究作一综述.