Objective To investigate the protective effects of ischemic postconditioning (IPo) on ischemiareperfusion (I/R) myocardium and the relationship with mitochondrial adenosine triphosphate (ATP) sensitive K+ channels (mitoKATP) and provide evidences to the development of druginduced postconditioning. Methods Langendorff models were established in 40 Wistar rats which were divided into 5 groups by random number table with 8 rats in each group. Normal control group(NC group): the rat hearts were continuously reperfused by KrebsHenseleit bicarbonate buffer (K-HB) for 100 min without any other treatment; I/R group: the rat hearts underwent a 40-min global ischemia followed by a 60-min reperfusion; IPo group: after a 40-min global ischemia, the process of 10-second reperfusion followed by a 10-second ischemia was repeated 6 times, then there was a continuous 58min reperfusion; 5-hydroxydecanoic acid(5-HD) group: after a 40min global ischemia, hearts with 5HD(100 μmol/L) K-HB were reperfused for 15min and then perfused without 5HD for 45min；IPo+5-HD group: after a 40-min global ischemia, the process that the isolated hearts with 5-HD(100 μmol/L) KHB were reperfused for 10second followed by a 10second ischemia was repeated 6 times, then the hearts with 5-HD(100 μmol/L) KHB were continuously [CM(159mm]perfused for 13-min followed by reperfusion without 5-HD(100 μmol/L) K-HB for 45-min. The cardiac function,coronary flow(CF), cardiac troponin I(cTnI) content in coronary effluent, the area of acute myocardial infarction (AMI) and myocardial ultrastructure were observed. Results Left ventricular developed pressure(74.3±3.3 mm Hg vs. 57.1±3.3 mm Hg,t=1300, P=0.000),+dp/dtmax(1 706.6±135.6 mm Hg/s vs. 1 313.3±96.2 mm Hg/s,t=6.28,P=0.000),－dp/dtmax(1 132.8±112.1 mm Hg/s vs. 575.7±67.7 mm Hg/s,t=13.48, P=0.000) and CF(6.49±0.30 ml/min vs. 3.70±0.24 ml/min,t=28.6,P=0.000) in IPo group were higher than those in I/R group. Left ventricular enddiastolic pressure(10.9±1.7mm Hg vs. 26.2±1.5 mm Hg,t=－19.21, P=0000)and cTnI content in coronary effluent (0.62±0.01 ng/ml vs. 0.71±0.01 ng/ml, t=-12.00,P=0.000) were lower than those in I/R group; the area of AMI decreased 20.8％ compared with that in I/R group (Plt;0.05). The myocardial protective effect in IPo+5HD group was similar with that in IPo group, but lower than that in IPo group. The electron microscope showed that IPo and IPo+5HD could reduce myocardial fiber damage and mitochondrial damage caused by I/R. Conclusion IPo can protect I/R myocardium, which is achieved mainly by activating mitoK-ATP channels.
目的 分析75岁以上高龄冠心病患者行冠状动脉旁路移植术（CABG）的治疗效果和临床经验。 方法回顾性分析山东省潍坊市人民医院和青岛市市立医院自2005年1月至2014年1月109例75岁以上行CABG术患者的临床资料。其中，男63例、女46例，平均年龄（78.1±4.2）岁，均为多支血管病变。术前心功能分级（NYHA） Ⅳ级23例、Ⅲ级57例、Ⅱ级29例。术中行非体外循环CABG （OPCABG） 92例，体外循环下行CABG （on pump CABG）术9例，体外循环辅助心脏不停跳下CABG （on pump beating heart CABG） 术8例。 结果 平均移植血管（2.5±1.4）支，围术期死亡4例，死亡率3.7%。其中，低心排血量综合征死亡1例，心律失常心室颤动死亡1例，肾衰和胃肠道并发症导致多器官衰竭死亡2例。术后主要并发症为心律失常、低心排血量综合征和肺部感染。105例生存患者95例获得随访，随访6～90 （45±26）个月，随访率90.5%。随访期间心源性死亡1例，非心源性死亡4例。患者心功能分级（NYHA）Ⅰ级81例，Ⅱ级18例，Ⅲ级2例，心绞痛消失。 结论 75岁以上冠心病患者行冠状动脉旁路移植术可改善患者症状，缓解心绞痛，提高生活质量，具有良好的近中期效果。
Abstract： Ischemia postconditioning is a new concept based on ischemic preconditioning. It has become a hot topic in protection of ischemic-reperfusion injury because of its effective protection, relative ease of application, and postconditioning. However, its precise mechanisms and most effective application methods are still unclear. This review covers recent progress in the understanding, developments (in remote postconditioning and pharmacological postconditioning), applications to the protection of heart, lung, liver, kidney, and brain, mechanisms and appropriate protocol of ischemic post-conditioning.
Abstract： Objective To observe the expression changes of microRNA 1 （miRNA-1） and microRNA 21（miRNA-21） after ischemic preconditioning （IPC）, ischemic postconditioning （IPO） and remote ischemic preconditioning （RIPC）in an ischemia-reperfusion rat heart model in vitro, as well as the expression of their target protein heat shock protein 70 （HSP70） and programmed cell death 4 （PDCD4）, and evaluate whether miRNA are involved in endogenous cardio-protective mechanism. Methods The Langendorff-perfused Sprague-Dawley rat hearts were randomly assigned into one of the four groups, control group （CON group, n=12）, ischemia preconditioning group （IPC group， n=12） , ischemia postconditioning group （IPO group， n=12） and remote ischemia preconditioning group （RIPC group，n=12）. Cardiac function was digitalized and analyzed. The expression of HSP70, PDCD4, B-cell lymphoma/leukemia-2 （Bcl-2） and Bax was detected by Western blotting. The expression of miRNA-1 and miRNA-21 was detected by real-time reverse transcriotion-polymerase chain reaction （RT-PCR）. Assessment of cardiac infarct size and myocardial apoptosis was determined using triphenyltetrazolium chloride （TTC） assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay （TUNEL） assay respectively. Results The expressions of miRNA-1 and miRNA-21 were up-regulated in IPC group, but the expression of miRNA-1 was down-regulated in RIPC group and IPO group （P＜0.05）. The expressionsof PDCD4, HSP70 and Bax were down-regulated in ‘conditioning’ groups compared with CON group （P＜0.05）. The expression of Bcl-2 was not statistically different among the four groups. The infarct size and the myocardial apoptosis in ‘conditioning’ hearts were significantly decreased compared with CON group （P＜0.05）. Conclusion The expressions of the miRNA-1 and miRNA-21 are different in IPC, RIPC and IPO groups, and their target proteins are not inversely correlated with the miRNAs in all the ‘conditioning’ groups.
Objective To explore the impact of ischemic postconditioning on ischemia-reperfusion injury in isolatedelderly rat hearts and their relation with P-Akt. Methods A total of 30 healthy elderly SD rats (21-23 months old， male or female) with their body weight of 450-500 g were divided into 3 groups: control group， ischemia-reperfusion group， and postconditioning group， with 10 rats in each group. Coronary artery blood flow，myocardial infarction size， phosphorylatedAkt （p-Akt） expression， and changes in myocardium and mitochondria were detected. Results Coronary artery blood flow of the postconditioning group was significantly higher than that of the ischemia-reperfusion group （6.4±1.2 ml/min vs.3.1±1.2 ml/min， P＜0. 01）， and myocardial infarction size of the postconditioning group was significantly smaller thanthat of the ischemia-reperfusion group （35.0%±2.0% vs. 55.7%±3.6%， Plt;0. 05）. The expression of P-Akt was significantlyhigher， and myocardial fibers and mitochondria were preserved better in the postconditioning group than the ischemia-reperfusion group. Conclusion Ischemic postconditioning can protect isolated elderly rat hearts against ischemia-reperfusion injury， which may be related to P-Akt activation.
Objective To investigate the application value of spiral CT postprocessing technique in the airway stent implantation technology. Methods Twenty-three patients with malignant airway stenosis or malignant tracheoesophageal fistula who needed the treatment of airway stent implantation from May 2012 to April 2016 were collected, including 19 males and 4 females with an average age of (61.6±10.0) years. Bronchoscopy and spiral CT with three-dimensional airway reconstruction were proceeded for the same patients before and after stent implantation, and the relevant data about narrow airway was measured by volume rendering, multiplanar reformation (MPR) and CT virtual endoscopy (CTVE) in a variety of ways, to confirm the location and size of narrow airway and fistulas, the degree and length of airway stenosis, as well as the distal end of the situation, and evaluate the patency of airway, the position and shape of stents, adjacent airway and complications after stenting. The positive forecast outcomes of the two inspections wascompared. Results Airway stents were placed successfully according to the data from the spiral CT airway three-dimensional reconstruction. Thirty stents were implantated in the 23 patients, including 21 column-type stents, 3 L-type stents, and 6 Y-type stents. All stents stayed in situ, with patency and no deformation.The fistulas were closed and the airways were reopened. Symptoms of cough after eating and drinking and dyspnea were relieved. The positive rates of bronchoscopy and CT examination on diagnosis of airway stenosis were both 100% (23/23). Complications: MRP showed tumor growth leading to stenosis again in 3 patients, and CTVE displayed mucous congestion in 2 patients. Conclusions The technique of 64-layer spiral CT postprocessing technique can measure the relate data of airway stricture or fistulas as a kind of convenient, quick, accurate, and noninvasive method in patients with malignant airway stenosis or tracheoesophageal fistula who need the treatment of airway stenting. It is of high reference value both to airway stent implanting and postoperative observation, and is worthy of application.
ObjectiveTo investigate the effect of post-conditioning with fospropofol disodium on hepatic ischemiareperfusion (I/R) and its possible mechanism in rats. MethodsForty-eight Sprague-Dawley rats were randomly divided into four groups, including sham group (S), control group (C), propofol group (P) and fospropofol disodium group (F). According to the different periods after reperfusion, each group was further divided into 2-hour and 4-hour reperfusion subgroups respectively (n=6 in each subgroup), named S2h, C2h, P2h, and F2h subgroups and S4h, C4h, P4h, and F4h subgroups. The livers of rats were reperfused after hepatic ischemia for one hour. In the beginning of reperfusion, normal saline was infused intravenously in group S and group C continuously, propofol was infused intravenously in group P continuously, fospropofol disodium was infused continuously in group F. The blood was sampled at the end of ischemia and reperfusion for assay of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The bcl-2 and bax protein contents in liver tissue were detected by immunohistochemical analysis, and liver samples were stained with hematoxylin-eosine for histological observation and damage degree evaluation by counting the proportion of necrosis cells. ResultsThe activity of ALT and AST, the rate of necrosis cells and the amount of bcl-2 and bax protein after reperfusion in group C, group P and group F were higher than those in group S at matched reperfusion time points (P<0.05). The activity of ALT and AST, the proportion of necrosis cells and bax protein contents decreased in group P and group F, compared with group C at the same reperfusion time points, while the contents of bcl-2 protein were significantly increased (P<0.05). ConclusionFospropofol disodium can alleviate hepatic injury induced by ischemia-reperfusion in rats, in which the bcl-2 and bax protein may play important roles.
ObjectiveTo explore the value and role of post-processing techniques such as 3D reconstruction in the online education mode in neurosurgery undergraduate clinical probation teaching.MethodsA retrospective analysis method was used to collect 120 clinical 5-year medical students who were trained in neurosurgery at West China Hospital of Sichuan University from January 2019 to May 2020, including 40 students receiving traditional imaging materials offline (control group 1), 40 students being taught on image post-processing technology offline (control group 2), and 40 students being taught on-line image post-processing technology during the novel coronavirus epidemic (observational group). The students’ scores of departmental rotation examination and feedback survey results on teaching satisfaction were collected, and multiple comparison was conducted between the observational group and the two control groups respectively.ResultIn the control group 1, the control group 2, and the observational group, the theoretical test scores were 36.80±3.22, 38.17±2.61, and 38.97±2.79, respectively; the case analysis scores were 37.05±2.01, 38.40±2.62, and 39.25±2.88, respectively; the total scores were 73.85±5.06, 76.57±4.29, and 78.10±4.53, respectively; the scores of interest in teaching were 84.47±3.71, 86.05±2.87, and 86.82±2.60, respectively; the scores of mastery of knowledge were 82.85±4.39, 84.90±2.72, and 85.78±2.36, respectively; and the scores of overall satisfaction with teaching were 84.17±3.45, 85.97±2.64, and 86.37±2.59, respectively. The differences among the three groups were all statistically significant (P<0.05). The observational group differed significantly from the control group 1 in all the above scores (P<0.05), while did not differed from the control group 2 in any of the above scores (P>0.05).ConclusionsIn neurosurgery internship activities, the online application of image post-processing techniques such as 3D reconstruction will help students establish 3D spatial concepts, better understand the brain anatomy, and improve students’ academic performance and acceptance.