Cardiac differentiation and electrophysiology characteristics of bone marrow mesenchymal stem cells

Objective  To review the progress of cardiac differentiation and electrophysiological characteristics of bone marrow mesenchymal stem cells.

Data sources  The databases of PubMed, Springer Link, Science Direct and CNKI were retrieved for papers published from January 2000 to January 2012 with the key words of “bone marrow mesenchymal stem cells, cardiac or heart, electrophysiology or electrophysiological characteristics”.

Study selection  The articles concerned cardiac differentiation and electrophysiological characteristics of bone marrow mesenchymal stem cells were collected. After excluding papers that study purposes are not coincident with this review or contents duplicated, 56 papers were internalized at last.

Results  For the treatment of myocardial infarction and myocardiac disease, the therapeutic effects of transplantation of bone marrow mesenchymal stem cells which have the ability to develop into functional myocardial cells by lots of methods have been proved by many researches. But the arrhythmogenic effect on ventricles after transplantation of bone marrow mesenchymal stem cells derived myocardial cells is still controversial in animal models. Certainly, the low differentiation efficiency and heterogeneous development of electricial function could be the most important risk for proarrhythmia.

Conclusion  Many studies of cardiac differentiation of bone marrow mesenchymal stem cells have paid attention to improve the cardiac differentiation rate, and the electrophysiology characteristics of the differentiated cells should be concerned for the risk for proarrhythmia as well.

     

术前肌电图和脑干听觉诱发电位与面肌痉挛微血管减压术后迟发性面瘫发生的关系(英文)

Background Delayed facial palsy ( DFP) after microvascular decompression ( MVD) in patients with hemifacial spasm ( HFS) is not uncommon,but the cause remains unknown. Objectives To assess whether intraoperative electromyography ( EMG) and brainstem auditory evoked potential ( BAEP) can predict DFP after MVD. Methods Between September 2009 and February 2011 we examined 86 patients,9 of whom ( 10. 4% ) developed DFP after MVD on the same side. All patients underwent MVD and were followed - up for a median period of 13 months ( range 6-22) . We retrospectively examined intraoperative facial EMG and BAEP findings using our MVD patients’ registry. We excluded secondary HFS and immediate postoperative facial palsy after MVD in this study. We assessed the prevalence and clinical characteristics of DFP and compared EMG and BAEP findings between DFP and non-DFP groups. Results: All pa- tients recovered completely,with a mean time to recovery of 37. 8 days ( range 22-57) . There were no significant differences between DFP and non - DFP patients in terms of the amplitude and latency of intraoperative EMG and BAEP. Conclusion The usefulness of intraoperative facial EMG and BAEP is limited and cannot predict DFP after MVD for HFS. We speculate that DFP after MVD is not associated with permanent nerve damage according to the EMG findings.     

Reassessment of the pharmacology of Sphingosine-1-phosphate S1P(3) receptor ligands using the DiscoveRx PathHunter™ and Ca(2+) release functional assays

BACKGROUND AND PURPOSE

DiscoverRx''s PathHunter™ assay measures GPCR agonist potency, via the recruitment of β-arrestin, independent of the subtype of G_α protein activated. This assay is frequently used in drug discovery although little is known about the agonist pharmacology generated. Here we have compared agonist potency, efficacy and affinity values obtained in PathHunter™ assays with those from more established radioligand binding and functional techniques.

EXPERIMENTAL APPROACH

Using cells expressing the human sphingosine-1-phosphate S1P₃ receptor at four different densities, we compared pharmacological affinity and efficacy values of four structurally distinct ligands – FTY720-P, VPC24191, CYM5442 and the endogenous agonist S1P – obtained from competition binding, functional Ca²⁺ release and PathHunter™ assays.

KEY RESULTS

The pK_i values for S1P were significantly different (9.34 ± 0.10 and 8.92 ± 0.15) in clones expressing different receptor levels using the binding assay. In the PathHunter™ and Ca²⁺ assays, S1P and CYM5442 were full agonists, FTY720-P was a partial agonist, while the efficacy of VPC24191 could not be detected in PathHunter™ assays. VPC23019, previously described as a S1P_1/3 receptor antagonist, behaved as an S1P₃ receptor partial agonist in the Ca²⁺ release assay.

CONCLUSIONS AND IMPLICATIONS

Comparison of data from the PathHunter™ assay with binding and functional Ca²⁺ assays suggest that PathHunter™ assays measured a different agonist-bound receptor conformation. While this assay has great utility in drug discovery, care must be taken as high-efficacy, low-affinity agonist compounds would not be detected. Therefore highly amplified, more traditional assays are necessary to identify agonists with low efficacy.     

骨形态蛋白2诱导大鼠骨髓间充质干细胞分化为心肌样细胞的实验研究

目的 观察骨形态蛋白2体外诱导骨髓间充质干细胞(BMMSCs)定向分化为心肌样细胞的作用.方法 采用密度梯度离心法分离大鼠BMMSCs,取第4代BMMSCs进行诱导:骨形态蛋白2组(BMP-2,终浓度为10 μg/L),空白对照组.诱导24h后更换常规培养液继续培养4周.倒置相差显微镜观察细胞的形态学变化,免疫荧光染色法鉴定诱导后BMMSCs中心肌特异性肌钙蛋白I(cTnI)的表达,Western Blot检测诱导2周和4周后Cx43以及cTnI的表达量,流式细胞计数法计算心肌样细胞诱导分化率.结果 原代培养的BMMSCs 2周形成集落,呈梭形或星形.传代细胞体积变大,诱导后细胞呈长梭形,呈一致性生长,并出现肌岛样结构.免疫荧光染色结果显示诱导后BMMSCs表达cTnI.Western Blot检测结果提示诱导后Cx43以及cTnI均明显增多,4周组明显高于2周组.流式细胞计数法显示:BMP-2组心肌样细胞诱导率为(17.9±0.8)％.结论 骨形态蛋白2可在体外诱导大鼠BMMSCs定向分化为心肌样细胞,其诱导分化率高.     

DBC1在肝癌组织中的表达及临床意义

目的检测DBC1蛋白在肝癌中的表达情况,分析并探讨其与肝癌临床病理参数间的相关性及意义。方法选取有详细临床资料的肝癌及其相匹配的癌旁组织120例,应用免疫组织化学改良二步法分别检测DBC1蛋白的表达,分析其与临床病理参数间的关系。结果 DBC1在肝癌组织中的表达阳性率为39.2%,明显低于相对应的癌旁组织97.5%(P<0.001)。DBC1的表达与性别、年龄、肿瘤大小无关,而与肿瘤TNM分期和组织学类型相关,差异具有统计学意义(P<0.01)。结论 DBC1在肝癌中低表达,其表达下调可能对肝癌的发生、发展具有重要作用,DBC1可能是肝癌的抑癌基因。     

主动脉球囊反搏治疗心源性休克患者的监护与护理

目的:观察主动脉球囊反搏(IABP)对心源性休克患者的临床疗效和分析护理经验。方法:对22例应用IABP治疗的患者,术前进行心理健康教育,术中密切监测生命体征,观察IABP运行状况和术后加强护理,预防并发症等。结果:22例患者接受IABP后循环稳定,血压回升,心功能逐渐改善,治疗好转后出院。结论:针对病因,应用IABP治疗可改善心功能,降低死亡率。     

上海地区34例百岁老人中医体质类型调查

目的了解上海地区百岁老人中医体质的分布情况。方法从上海市各区县随机抽取34例百岁老人。由专职医师经系统培训后统一入户,采用《中医体质分类与判定表》进行问卷调查,判定中医体质类型。结果34例百岁老人,男性18例,年龄101～110岁,平均（103．5±2．5）岁;女性16例,年龄101～113岁,平均（106．1±3．4）岁,2例由于精神原因失访。男性以阳虚质最多9例占34．6％,其次为平和质8例（30．8％）、气虚质6例（23．1％）、痰湿质1例（3．8％）、血瘀质1例（3．8％）、特禀质1例（3．8％）。女性以平和质最多10例占52．6％,其次为气虚质6例（31．6％）、阳虚质2例（10．5％）、血瘀质1例（5．3％）。没有百岁老人表现出阴虚质、湿热质和气郁质。20例舌质淡红,9例舌质淡白,3例舌质黯。13例苔质薄,15例苔质腻,4例少苔。27例苔色白,5例苔色黄。20例细脉,9例弱脉,16例弦脉,2例滑脉,1例沉脉,3例结脉。结论本组百岁老人平和质最多,与“阴平阳秘,精神乃治”的中医理论相符,大多数老人善于保存体内的阴气,脏腑机能正常,气血津液充盈,胃气旺盛,但在脉象上却难掩衰老之势。     

养血活血治疗女性更年期皮肤瘙痒症

更年期妇女正值七七前后,天癸阴精、肾气由盛渐衰,精血日趋不足,阴阳平衡失调。通过调养体内精血,达到治标又治本效果。治疗以调理气血为主,采用养血活血药物枸杞、当归各10g,阿胶15g,白芍5g,2次/d,水煎200mL,早晚口服,7d为1个疗程。