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1.
【目的】观察黄芪甲苷体外诱导骨髓间充质干细胞(MSCs)定向分化为心肌样细胞的作用。【方法】采用密度梯度离心和贴壁培养法分离大鼠MSCs,反复传代及纯化后,取第3代MSCs,采用流式细胞仪检测细胞表面抗原CD34和CD44;取第8代MSCs进行分组诱导:黄芪甲苷组(终浓度为250 mg/L)、5-氮胞苷(5-aza,终浓度为10μmol/L)、黄芪甲苷加5-aza组(终浓度分别为250 mg/L与10μmol/L),并设空白对照组,诱导后继续培养4周;计算心肌样细胞诱导率,采用免疫组化法鉴定诱导后MSCs中结蛋白(Desmin)和心肌特异性肌钙蛋白I(cTnI)的表达,采用逆转录聚合酶链反应(RT-PCR)法鉴定诱导后MSCs中心肌特异性蛋白α-心肌肌球蛋白重链(-αMHC)和β-心肌肌球蛋白重链(-βMHC)信使核糖核酸(mRNA)的表达。【结果】原代培养的MSCs首先形成集落,传代细胞体积变大,诱导后细胞呈梭形,并出现肌管;MSCs表面抗原CD44表达阳性,而骨髓造血干细胞表面抗原CD34表达阴性,表明本实验方法所得细胞为均一的MSCs细胞群;各组在不同时间的心肌样细胞诱导率无明显差异;免疫组化结果显示诱导后MSCs表达心肌特异性蛋白Desmin和cTnI;RT-PCR结果显示诱导后MSCs表达成熟的心肌特异性蛋白-αMHC和-βMHC。【结论】黄芪甲苷可在体外诱导大鼠MSCs定向分化为心肌样细胞,但诱导率仍有待提高。  相似文献
2.
【目的】观察三七总皂苷(PNS)对大鼠骨髓间充质干细胞(MSCs)增殖和体外诱导其分化为心肌样细胞的作用。【方法】采用骨髓细胞体外培养技术分离大鼠MSCs,以流式细胞仪检测细胞表面标志;采用四甲基偶氮唑盐(MTT)法观察PNS对MSCs增殖的影响;采用第8代MSCs进行体外心肌细胞诱导分化;采用相差显微镜、免疫组化及逆转录聚合酶链反应(RT-PCR)结果鉴定心肌细胞。【结果】大鼠MSCs细胞表面抗原CD44阳性,CD34阴性;经PNS作用后MSCs增长速度比空白对照组明显加快,体外诱导后细胞形态发生变化,其细胞免疫组化鉴定呈结蛋白(Desmin)、肌钙蛋白(cTnI)阳性;RT-PCR结果显示诱导后细胞转录肌球蛋白重链mRNA水平增加。【结论】PNS能促进大鼠MSCs体外增殖并可诱导MSCs分化为心肌样细胞,这为细胞移植治疗心肌梗死提供了实验依据。  相似文献
3.
Yan HB  Wang J  Li N  Zhu XL  Gao H  Ai H  Li X  Ye M  Chi YP  Zhang H 《中华医学杂志(英文版)》2007,120(7):557-561
Background Different feasible and safe thrombectomy and distal protection devices have been used in clinical practice. The efficiency and safety of adjunct thrombectomy using Diver CE device (Invatec, Italy) versus Guardwire Plus device (Medtronic, USA) before percutaneous coronary intervention (PCI) were compared in patients with acute inferior ST-segment-elevation myocardial infarction (STEMI) for less than 12 hours, thrombolysis in myocardial infarction (TIMI) flow grade 0 to 1, and total occlusion of the proximal right coronary artery (≥3 mm in diameter) in a prospective randomized single-center study.Methods The primary end point was the magnitude of ST-segment resolution (STR) (>70% ) measured immediately, 90 minutes and 6 hours after PCI, myocardial blush grade and slow flow or no-reflow. Secondary end points were left ventricular end-diastolic volume (LVEDV), left ventricle ejection fraction (LVEF) and major adverse cardiac events (MACEs) including death, myocardial infarction, target vessel revascularization and stroke at 30 days.Results A total of 122 patients were equally divided into Diver CE group and Guardwire Plus group, which were comparable by age ((60±14) years vs (60±13) years), male (82% vs 84%), diabetes (31% vs 28%), previous coronary artery disease (25% vs 23%), onset-to-angiogram ((350±185) min vs (345±180) min), and use of glycoprotein IIb/IIIa inhibitor (11% vs 13%). The magnitude of ST-segment resolution was similar in the two groups as ST-segment resolution >70% (57% vs 59%; P>0.05). Similar slow flow/no-reflow rates were observed in the Diver CE group (8%) and the Guardwire Plus group (7%). TIMI flow grade 3 was obtained in 95% vs 97% patients, respectively (P>0.05). Myocardial blush grade 3 was similar (70% vs 72%; P>0.05). Thirty-day clinical outcome was comparable (LVEF, 0.54±0.12 vs 0.53±0.11; death, 3% vs 3%; myocardial infarction, 2% vs 0%; and target vessel revascularization, 2% vs 2%; P>0.05, respectively). Conclusions Removal of thrombus burden with the Diver CE catheter before stenting leads to similar improvement of myocardial reperfusion in patients with inferior STEMI and total occlusion of the proximal right coronary artery (≥3 mm in diameter) compared with the Guardwire Plus device, as illustrated by a reduced risk of distal embolization and improved ST-segment resolution.  相似文献
4.
目的:观察丹参多酚酸盐对猪急性心肌梗死后心肌细胞凋亡及心功能的影响。 方法:苏中幼猪21只,随机分为模型组和低、高剂量丹参多酚酸盐组。3组均经开胸结扎冠状动脉左前降支制作心肌梗死模型,造模成功后当日.高剂量丹参多酚酸盐组给予400mg丹参多酚酸盐加250 mL 5%葡萄糖生理盐水静脉滴注;低剂量丹参多酚酸盐组给予200mg丹参多酚酸盐加250 mL 5%葡萄糖生理盐水静脉滴注;模型组给予等体积的5%葡萄糖生理盐水静脉滴注。1次/d,连续给药7d。造模后4周,行核素门控心肌灌注显像评价各组动物心功能;处死动物,取心脏标本做石蜡切片,原位缺口末端标记法染色,高倍镜下计数心肌细胞凋亡指数。 结果:高、低剂量丹参多酚酸盐组动物梗死周边缺血区的,心肌细胞凋亡指数均明显下降,高剂量丹参多酚酸盐组与模型组比较。差异有统计学意义(P〈0.05)。心肌梗死后4周行核素门控心肌灌注显像,3组动物的梗死区均可见放射性稀疏区,但高、低剂量丹参多酚酸盐组放射性稀疏区较模型组明减显小。高剂量丹参多酚酸盐组心肌灌注得分与模型组相比,差异有统计学意义(P〈0.05);高剂量丹参多酚酸盐组动物的左室射血分数也高于模型组(P〈0.05)。 结论:静脉维持应用丹参多酚酸盐,能够减少猪急性心肌梗死后心肌细胞凋亡,促进梗死心脏心功能的改善,发挥心脏保护作用。  相似文献
5.
Background A growing volume of data suggests that simple manual thrombus aspiration followed by direct stenting improves myocardial reperfusion and clinical outcome compared with conventional primary PCI, but there is still limited data comparing the in vivo performance among different devices. This study aimed to compare the efficacy and operability of thrombus aspiration by the Diver CE (Invatec, Brescia, Italy) and ZEEK (Zeon Medical Inc., Tokyo, Japan) aspiration catheters in ST-segment elevation myocardial infarction (STEMI) and their impact on 3-month outcome.
Methods From September 2004 to June 2008, 298 consecutive patients with STEMI who received manual thrombus aspiration were involved in a single center retrospective analysis. Of them, 229 and 69 were treated with Diver CE and ZEEK aspiration catheters, respectively. Primary endpoints were myocardial blush grade (MBG), thrombolysis in myocardial infarction (TIMI) flow grade, ST-segment elevation resolution (STR), device pushability and trackability as judged by the frequency of usage of dual guide wires and aspiration efficacy as indicated by size distribution of aspirated thrombi. Secondary endpoints were 3-month outcome including left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), as well as cardiac death, target lesion revascularization (TLR), re-infarction and their combination as major adverse cardiac events (MACE). Results Baseline characteristics were not different between the two groups expect for a higher frequency of temporary cardiac pacing in the ZEEK group (ZEEK) than in the Diver CE group (Diver CE) (0.44% vs 5.8%, P=0.002). Visible retrieved thrombi were achieved in 65.9% of the Diver CE and 68.1% of the ZEEK (P=0.74). Aspirated thrombi were categorized as small thrombi (〈3.5 mm), moderate thrombi (3.5-7.0 mm) and large thrombi (〉7.0 mm). Small thrombi were more frequently seen in the Diver CE (61.6% vs 42.6%), whereas moderate and larger thrombi were more frequently found in the ZEEK (38.4% vs 57.4%) (P=0.021). Rates of dual wire utilization were 1.7% of the Diver CE and 7.2% of the ZEEK (P=0.052). There were no differences in MBG, STR and TIMI flow grade between the two groups. No differences were found in cardiac death, TLR, re-infarction, MACE, LVEDD and LVEF between the Diver CE and the ZEEK during 3-month follow-up.
Conclusions Both Diver CE and ZEEK manual aspiration catheters are effective for thrombectomy in STEMI. In clinical practice, ZEEK presents a stronger aspiration capacity for moderate to large thrombi compared with Diver CE, but Diver CE displays a trend towards better pushability and trackability than ZEEK. Differences in aspiration capacity and operability between Diver CE and ZEEK in this setting do not influence myocardial reperfusion and 3-month outcome.  相似文献
6.
经皮桡动脉入路直接冠状动脉介入治疗急性心肌梗死   总被引:10,自引:0,他引:10       下载免费PDF全文
目的:探讨经皮桡动脉入路介入治疗在急性心肌梗死中的应用.方法:急性心肌梗死患者107例,其中56例行直接经皮桡动脉入路冠状动脉介入(PCI)治疗(A组),51例行直接经皮股动脉入路PCI(B组),比较两组的穿刺成功率、PCI成功率、血管开通时间、手术总时间、穿刺点并发症.结果:A、B两组穿刺成功率均为100%,PCI成功率均大于96%,鞘管置入时间[(2.93±0.42) vs (3.07±0.54) min, P=0.14]、血管再通时间[(17.23±3.47) vs (16.81±4.86) min, P=0.61]、手术总时间[(47.04±7.53) vs (48.74±6.22) min, P=0.21]等差异均无统计学意义.B组穿刺点局部出血、血肿发生率(5/51, P=0.016 4)及拔管迷走反射(4/51, P=0.032 7)均明显高于A组(0/56).结论:经皮桡动脉入路介入治疗行急诊PCI是安全可行的,而且能减少穿刺点并发症.  相似文献
7.
Background Adipose-derived stem cells (ADSCs) are capable of differentiating into cardiomyogenic and endothelial cells in vitro. We tested the hypothesis that transplantation of ADSCs into myocardial scar may regenerate infracted myocardium and restore cardiac function. Methods ADSCs were isolated from the fatty tissue of New Zealand white rabbits and cultured in Iscove's modified dulbecco's medium. Three weeks after ligation of left anterior descending coronary artery of rabbits, either a graft of untreated ADSCs (UASCs, n=14), 5-azacytidine-pretreated ADSCs (AASCs, n=13), or phosphate buffer saline (n=13) were injected into the infarct region. Transmural scar size, cardiac function, and immunohistochemistry were performed 5 weeks after cell transplantation. Results ADSCs in culture demonstrated a fibroblast-like appearance and expressed CD29, CD44 and CD105. Five weeks after cell transplantation, transmural scar size in AASC-implanted hearts was smaller than that of the other hearts. Many ADSCs were differentiated into cardiomyocytes. The AASCs in the prescar appeared more myotube-like. AASCs in the middle of the scar and UASCs, in contrast, were poorly differentiated. Some ADSCs were differentiated into endothelial cells and participate in vessel-like structures formation. All the ADSC-implanted hearts had a greater capillary density in the infarct region than did the control hearts. Statistical analyses revealed significant improvement in left ventricular ejection fraction, myocardial performance index, end-diastolic pressure, and peak +dP/dt, in two groups of ADSC-implanted hearts relative to the control hearts. AASC-implanted hearts had higher peak -dP/dt values than did control, higher ejection fraction and peak +dP/dt values than did UASC-implanted hearts. Conclusions ADSCs transplanted into the myocardial scar tissue formed cardiac islands and vessel-like structures, induced angiogenesis and improved cardiac function. 5-Azacytidine pretreatment before implantation is desirable for augmenting myogenesis. Transplantation of 5-azacytidine-treated ADSCs into the myocardial scar was more efficient than that of untreated ADSCs in preservation of cardiac function.  相似文献
8.
冠心病患者血浆脑钠肽N末端前体浓度的变化及临床意义   总被引:9,自引:0,他引:9  
目的 分析稳定型心绞痛(SAP)、不稳定型心绞痛(UAP)和非ST段抬高型心肌梗死(NSTEMI)患者以及冠脉介入治疗前后血浆中的脑钠肽(BNP)N末端前体(NT-proBNP)水平的变化,评价血浆NT-proBNP水平与不同冠心病类型的关系,以及心肌缺血改善后血浆NT-proBNP水平的变化.方法 选择住院冠心病患者345例,其中NSTEM组29例,UAP组151例,SAP组165例:同时设正常对照组140例.采用电化学发光双抗体夹心免疫法检测血浆NT-proBNP水平,同时对180例急性冠状动脉综合征(ACS)患者经皮冠状动脉介入治疗(PCI)后的上述指标进行分析.结果 NSTEMI组NT-proBNP水平明显高于其他三组(P<0.05),UAP组高于SAP组(P<0.05),SAP组高于正常对照组(P<0.05),其中180例ACS患者在经皮冠脉介入术后12~24 h内,血浆NT-proBNP水平UAP组从术前的(1720.53±610.77)ng/L降为(1020.52±510.70)ng/L(P<0.05),NSTEMI组从术前的(5660.23±1290.53)ng/L降为(2640.20±890.50) ng/L(P<0.05);术后1周NT-proBNP水平,UAP组降为(359.05±230.33) ng/L;NSTEMI组降为(360.30±210.26)ng/L;与对照组比较均无显著性差异(P>0.05).血浆NT-proBNP值与心肌TIMI血流评分相关(r=-0.402,P<0.001).结论 冠心病患者血浆NT-proBNP浓度增高;NT-proBNP水平增高可以预测冠心病的严重程度;ACS患者冠脉介入治疗后血浆NT-proBNP含量明显降低,可作为观察疗效的指标,对临床病情的评估具有重要价值.  相似文献
9.
葛根素预处理保护心肌缺血再灌注损伤的机制   总被引:9,自引:0,他引:9  
目的:探讨线粒体ATP敏感性钾通道(mitoKATP)是否参与葛根素(puerarin,PUE)预处理保护心肌缺血再灌注损伤的机制.方法:开胸结扎左冠状动脉前降支(LAD),复制大鼠心肌缺血再灌注损伤模型,设立假手术(sham)组、缺血再灌注(I/R)组、PUE预处理组,PUE预处理加mitoKATP特异性阻断剂5-hydroxydecanoate(5-HD)组和5-HD组,采用TTC法测定心肌梗塞面积,TUNEL法检测心肌细胞凋亡情况,并测定血清肌酸激酶(CK)活力.结果:I/R组较sham组心肌梗塞面积、血清CK活力以及心肌细胞凋亡指数显著增高;与I/R组比较,PUE预处理组心肌梗塞面积明显缩小,血清CK活力和心肌细胞凋亡指数显著降低;PUE加5-HD组与PUE预处理组相比心肌梗塞面积增大,心肌细胞凋亡增加,血清CK活力增高;5-HD组与I/R组相比以上指标差异均无显著意义.结论:葛根素预处理明显减轻了大鼠心肌I/R损伤,其心肌保护效应可能部分通过开放mitoKATP通道的途径产生.  相似文献
10.
目的 研究静脉应用重组人脑利钠肽(rhBNP)对急性心肌梗死经皮冠状动脉介入治疗(PCI)术后患者心室重塑和左心功能的影响。方法 选择48例发病12h内的急性前壁心肌梗死PCI术后患者,随机分为rhBNP组25例和常规治疗组23例,分别于发病后1周、4周和24周采用二维超声心动图测定舒张末期容积指数(LVEDVI)、收缩末期容积指数(LVESVI)、左室射血分数(LVEF)、左室质量指数(LVMI),计算梗死区的局部室壁运动指数(RWMI)。结果 两组患者治疗1周时LVEDVI、LVESVI、LVEF、RWMI、LVMI间差异均无显著性意义(P〉0.05);治疗4、24周时LVEDVI、LVESVI、LVEF以及治疗24周时RWMI、LVMI间差异均有显著性意义(P〈0.05)。结论 PCI术后在常规治疗的基础上应用rhBNP可进一步阻抑急性前壁心肌梗死后心室重塑,改善左心功能。  相似文献
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