同种异体半月板移植的研究进展

膝关节半月板具有重要的生物力学功能，它是维持膝关节正常生理功能的重要组成部分，它可以增加关节软骨面之间的接触面积，减小关节面单位面积上的压力，其楔形结构可增加膝关节的稳定性，缓冲纵向压力。半月板切除后必然导致韧带松驰，关节不稳，软骨面磨损加快，加速膝关节退行性改变，为了避免这些并发症的发生，     

靶向daintain/AIF-1的siRNA抑制乳腺癌细胞MDA-MB-231的增殖和迁移

目的构建靶向daintain/AIF-1的siRNA表达载体pRNAT-H1.1-daintain/AIF-1(pRNAT-DT),研究靶向daintain/AIF-1的siRNA对乳腺癌细胞MDA-MB-231增殖和迁移的影响。方法设计合成靶向dain-tain/AIF-1的siRNA模板双链,将其克隆入siRNA空载体pRNAT-H1.1,用脂质体法导入乳腺癌细胞MDA-MB-231中;RT-PCR和Western印迹方法检测daintain/AIF-1以及cyclinD1的表达;MTT方法检测细胞增殖;流式细胞仪检测细胞周期;Trans-well细胞板检测细胞迁移。结果针对序列1和序列2的siRNA表达载体pRNAT-DT均能有效抑制daintain/AIF-1的表达。靶向daintain/AIF-1的siRNA抑制细胞增殖和cyclinD1表达,阻滞细胞周期由S期向G2/M期转变。同时,daintain/AIF-1表达的下调抑制了细胞的迁移。结论靶向daintain/AIF-1的siRNA抑制乳腺癌细胞MDA-MB-231的增殖和迁移。     

实验性冷冻保存带血管的同种异体骨移值

为探讨应用吻合血管的冷冻保存同种异体肋骨移植修复骨缺损的可能性，以15％二甲基甲砜(DMSO)作为低温保护剂，采用两步玲冻步骤，对狗的含后肋问血管的肋骨段进行冷冻处理，在液氟中保存96h后，施行同种异体移植于髂嵴骨缺损区。术后3周内使用免疫抑制剂。对移植体进行免疫学(白细胞个素Ⅱ、T细胞亚群)监测，SPECT扫描、血管造影和病理学分析。实验结果表明，同种异体移植肋骨段血循环丰富，骨细胞代谢活跃，未发生急性排斥反应，3个月达骨性愈台，取得了类似于吻合血管的自体骨移植的效果。     

脱细胞处理的同种异体神经移植研究进展

周围神经损伤的修复是创伤外科难题之一,筛选促进神经再生理想的移植物,是解决这一难题的关键。近年来,在修复周围神经缺损研究中采用脱细胞处理的同种异体神经作为移植物,已取得促进神经再生的效果,展示了较好的应用前景。本文对脱细胞处理移植体的脱细胞处理方法,脱细胞处理后的细胞外基质所含的生物活性物质,以及这些物质的对促进神经再生的生物效应进行综述,以期为此种移植体的深入研究提供参考资料。     

同种异体移植炎性因子-1:一种多功能的炎性蛋白质

同种异体移植炎性因子-1(allograft inflamuatory factor-1,AIF-1)是由143个氨基酸组成的小分子蛋白质,链内含有一个可与Ca2 结合的EF-手形结构域。AIF-1最初发现于同种大鼠的异体移植心脏。AIF-1被证明与机体的免疫应答、血管病变及生殖功能紧密相关,并能调节细胞的增殖及迁移,是一种多功能的炎症蛋白质。     

带血管的同种异体关节移植进展

因剖伤、肿瘤或其它病因引起的关节缺损是医学中治疗的难题。近年来，国外学者进行了一系列的带血管同种异体关节移植实验研究，研究的重点仍然是克服移植排斥反应，综述如下：     

同种异体器官移植排斥反应的细胞免疫机制

移植排斥反应的细胞免疫机制的研究，为免疫抑制治疗提供了重要的理论依据和途径。本文综述了同种异体排斥反应中ＭＨＣ抗原提呈、Ｔ细胞抗原识别、Ｔ细胞激活和分化、Ｔ细胞免疫效应等机制的研究进展。     

同种异体肌腱移植的有关生物力学问题

腱是致密的、规则的胶原组织,它主要由平行排列的堆积成的胶原纤维组成,其它组成材料包括弹性纤维、网状纤维、蛋白多糖以及水等。胶原纤维使其具有一定的强度和刚度,弹性纤维使其具有在载荷下具有延伸的能力,而网状纤维提供容积。胶原组织附加成份为基质,是一种胶状材料,能减少纤维间的摩擦。而且研究表明,基质的完整性对腱的机械完整性是非常重要的,酶对于非胶原成份的消化作用可在很大范围内改变腱的力学特性。在运动过程中,腱主要承受张力,自身不会产生主动活动。大部分韧带（除项韧带、黄韧带外）具有和腱相似的物质结构     

吻合血管同种异体骨移植动物模型的建立

目的:为吻合血管同种异体骨移植提供理想的动物模型。方法:日本大耳白兔雌21只为供体,雄42只为受体,对股骨滋养血管进行显微解剖观测,在此基础上设计吻合血管同种异体股骨干移植术,并设立应用环孢素A的实验组和未予任何免疫抑制剂的对照组。结果:股骨干的滋养孔位于小粗隆前下方3.0mm,滋养动脉起始于旋股外侧动脉,管径0.3mm,斜向外下入滋养孔,干长1.7cm,伴行静脉1条。实验组术后一般情况正常,血管吻合口通畅,骨愈合良好;对照组术后出现脱毛,腹泻,死亡等GVHD现象,术肢出现血管早期栓塞,非感染性坏死组织,骨愈合不良等HVGR征象。结论:本动物模型滋养血管解剖恒定,可操作性强,且能较好地复制免疫排斥反应及体现免疫抑制剂对吻合血管同种异体骨移植的调控作用。     

Rap1 promotes proliferation and migration of vascular smooth muscle cell via the ERK pathway

Background

Rap1 is involved in a multitude of cellular signal transduction pathways, which has extensively been linked to cell proliferation and migration. It has been shown to be important in the regulation of physiological and pathological processes. The present study aims to elucidate its detailed mechanistic in proliferation and migration.

RNA interference targeting ORC1 gene suppresses the proliferation of vascular smooth muscle cells in rats

Background

The proliferation of vascular smooth muscle cells (VSMCs) plays an important role in the pathogenesis of vascular diseases such as atherosclerosis and postangioplasty restenosis. The largest subunit of the origin recognition complex (ORC), ORC1, plays a critical role during the initiation of DNA replication in eukaryotes. However, the involvement of ORC1 in the initiation of DNA replication in VSMCs has not been studied yet.

Objective

The aim of this study was to silence ORC1 gene selectively by using RNA interference and analyze the effects of ORC1 gene on the proliferation and apoptosis of rat VSMCs.

Methods

Freshly isolated rat VSMCs were transfected with siRNA targeting ORC1 gene capsulated in liposome. ORC1 protein expression was determined by Western blotting and ORC1 mRNA level by RT-PCR. DNA synthesis was analyzed by ³H thymidine (³H-TdR) incorporation and cell proliferative activity and cell cycle distribution by flow cytometry. Two apoptosis-related proteins, Bax and Bcl-2, were examined immunohistochemically.

Results

Down-regulation of ORC1 mRNA and protein expression was observed in rat VSMCs at 24 h after transfection with the three pairs of siRNA targeting ORC1 gene and this reduction persisted at least 7 days post-transfection. Down-regulation of ORC1 mRNA (60%) and protein (80%) expression was observed at 72 h post-transfection in the cells transfected with B-ORC1 siRNA. A significant decrease in ³H thymidine incorporation was observed in rat VSMCs with ORC1 gene silencing after serum challenge, but not in the non-silenced control. A significant increase in the proliferation index and a significant decrease in the percentage of cells at G₀/G₁ phase after serum challenge were observed in the non-silenced control, but not in ORC1 gene silenced cells. A significant increase in the ratio of Bcl-2/Bax was observed after serum challenge in the non-silenced control, but only a slight increase was found in the ORC1 gene silenced cells. ORC1 gene silencing disappeared 7 days after transfection. Continuous serum challenge stimulated VSMCs to synchronously reenter the cell cycle as evidenced by increases in [³H] thymidine incorporation, the proliferation index, and the ratio of Bcl-2/Bax, as non-silenced cells were induced to resume cell cycle progression by the addition of 15% fetal bovine serum to the culture medium.

Conclusion

ORC1 gene silencing causes rat VSMCs to enter a reversible G₀ quiescent, growth arrested state; thus, ORC1 gene may be an important new target for suppressing VSMCs proliferation.     

雌激素对大鼠血管平滑肌细胞囊泡素-1基因表达的影响

目的:探讨雌激素对血管平滑肌细胞囊泡素-1基因表达的影响。方法:取Wistar雌性大鼠,分为3组:假手术组,卵巢切除后皮下埋植雌激素组 (OVX+E组)及卵巢切除后皮下埋植安慰剂组(OVX+V组)。用药2周后处死大鼠,剥离主动脉平滑肌组织,提取总RNA进行半定量RT-PCR分析,检测雌激素对囊泡素-1(caveolin-1)基因表达的影响。为进一步明确雌激素是否直接调节血管平滑肌细胞caveolin-1基因表达,又采用100 nmol/L 17β-雌二醇(17β-E₂)处理培养的大鼠血管平滑肌细胞24 h,通过Northern blot分析检测雌激素对细胞caveolin-1 mRNA表达的影响。结果:OVX+E组大鼠主动脉平滑肌组织caveolin-1基因表达量明显高于OVX+V组,17β-E₂处理的培养细胞中caveolin-1基因mRNA表达量高于未用药的培养细胞。 结论:雌激素可促进血管平滑肌细胞caveolin-1基因表达,反映了雌激素心血管作用机理的一个方面。     

Influence of Cyclooxygenase-2 (COX-2) gene promoter-1195 and allograft inflammatory factor-1 (AIF-1) polymorphisms on allograft outcome in Hispanic kidney transplant recipients

Cyclooxygenase-2 (COX-2) alleles have been associated with allograft outcomes in kidney transplant recipients; however, these alleles may be in linkage with other genes. Human allograft inflammatory factor-1 (AIF-1) is a cytoplasmic protein and is produced by macrophages. Its synthesis is regulated by several cytokines, including interferon gamma. We investigated whether polymorphisms of gene encoding COX-2 and AIF-1 were associated with allograft outcomes among Hispanic renal transplant recipients (RTRs).     

麝香保心丸对内皮素-1诱导原代培养的人脐动脉血管平滑肌细胞增殖的影响

目的:观察麝香保心丸(SXBXW)对内皮素-1(ET-1)诱导原代培养的人脐动脉血管平滑肌细胞(VSMCs)增殖作用的影响。方法:建立ET-1刺激原代培养人脐动脉VSMCs增殖的细胞模型,设对照组、ET-1组、ET-1+SXBXW0.25g/L组、ET-1+SXBXW0.5g/L组、ET-1+SXBXW1.0g/L组和ET-1+SXBXW2.0g/L组,采用MTT法测定ET-1和SXBXW对细胞增殖的影响;用台盼蓝拒染和乳酸脱氢酶检测方法观察不同浓度的SXBXW对VSMCs的毒性作用;用流式细胞术观察ET-1和SXBXW对VSMCs增殖周期的影响。结果:与对照组相比,ET-1可显著促进VSMCs的增殖,一定剂量的SXBXW能够有效地抑制ET-1诱导的VSMCs细胞增殖,呈剂量依赖性;SXBXW抑制细胞增殖,但对活细胞数目和乳酸脱氢酶释放量均没有影响,提示对VSMCs无毒性作用。ET-1能够刺激VSMCs从G1期进入S期,从而促进细胞增殖,而SXBXW能抑制这一作用。结论:SXBXW能够有效抑制ET-1诱导的VSMCs增殖作用,其作用机制可能与其抑制细胞周期从G1期进入S期有关。     

Intracellular free calcium concentration / force relationship in rabbit inferior vena cava activated by norepinephrine and high K+

The changes in isometric force and the underlying fluctuations in intracellular free calcium concentration ([Ca²⁺]_i) were monitored simultaneously in thin sheets of rabbit inferior vena cava loaded with the fluorescent Ca²⁺ indicator fura-2. In resting tissues bathed in physiological saline solution, the estimated [Ca²⁺]_i was approximately 105 nM. The -adrenergic agonist norepinephrine (10 M) caused an initial rise in [Ca²⁺]_i to 264 nM during force development, which dropped to 216 nM during force maintenance. The maintained norepinephrine-induced increase in force and [Ca²⁺]_i was reversed in Ca²⁺-free (2 mM EGTA) solution. Membrane depolarization by high K⁺ (80 mM) significantly increased [Ca²⁺]_i to 234 nM. Compared to norepinephrine, high K⁺ caused about the same steady-state increase in [Ca²⁺]_i, but a smaller increase in force. [Ca²⁺]_i/force curves were constructed at different concentrations of extracellular Ca²⁺, with either norepinephrine or high K⁺ as a stimulant. The curve generated with norepinephrine was located to the left of that generated with high K⁺.     

银杏叶提取物诱导大鼠主动脉平滑肌细胞HO-1的表达及细胞信号通路研究

目的： 旨在研究银杏叶提取物（Ginkgo Biloba Extract,EGB761）对大鼠主动脉平滑肌细胞(RVSMC)血红素氧合酶-1（HO-1）蛋白的影响,并探讨其中涉及的细胞信号通路。方法: 大鼠主动脉平滑肌细胞株复苏、传代培养到第6代，再复孔培养用于实验，分别给予空白对照、单纯EGB761、EGB761＋锌原卟啉Ⅸ(ZnPPⅨ)或不同的细胞内信号途径特异性阻断剂进行处理，采用Western blotting法定量检测HO-1蛋白表达。结果: EGB761能呈剂量依赖性诱导HO-1蛋白表达，加用ZnPPⅨ（血红素氧合酶特异性阻断剂）及酪氨酸蛋白激酶(TPK)阻断剂木黄酮均能显著抑制EGB761诱导的HO-1蛋白表达（均P<0.01），但calphostin-C（蛋白激酶C阻断剂）、LY294002（磷脂酰肌醇-3激酶阻断剂）及Bay11-7082（核因子-κB阻断剂）对EGB761诱导的HO-1蛋白表达无明显影响（均P>0.05）。结论: (1) EGB761能显著诱导RVSMC中HO-1蛋白的表达，并且这种诱导作用能被血红素氧合酶的特异性阻断剂ZnPPⅨ所阻断。（2）EGB761通过TPK途径介导大鼠主动脉平滑肌细胞HO-1蛋白的表达。     

STAT3介导了血小板源性生长因子BB诱导的大鼠血管平滑肌细胞Pim-1表达

 目的： 观察血小板源性生长因子BB(PDGF-BB)是否可以诱导大鼠血管平滑肌细胞（VSMCs）表达Pim-1及Pim-1对VSMCs增殖的影响,探讨STAT3信号分子在这一过程中的作用,为血管重建性疾病（VRD）的研究提供实验依据。方法： 不同浓度PDGF-BB作用不同时间刺激体外培养的VSMCs,用细胞计数法检测增殖;用real-time RT-PCR 检测Pim-1 mRNA表达水平;Western blotting 检测STAT3 的活性变化;用放线菌素D（actinomycin D）、AG490（JAK特异性抑制剂）及siRNA沉默Pim-1和STAT3进行干预。结果： PDGF-BB（20 μg/L）作用VSMCs 24 h,可以诱导细胞增殖,Pim-1沉默抑制了这一过程;正常未经处理的VSMCs Pim-1 mRNA表达量较低,不同浓度PDGF-BB（10 μg/L~50 μg/L ）作用VSMCs 1 h,Pim-1 mRNA表达明显增加,其中以20 μg/L最显著;用PDGF-BB（20 μg/L）作用VSMCs 不同时间（0.5 h~4 h）,可显著上调Pim-1 mRNA表达,以0.5 h最显著。用actinomycin D及AG490预处理后Pim-1 mRNA表达随之降低。PDGF-BB可激活VSMCs中磷酸化STAT3水平,AG490和转染STAT3-siRNA可抑制 STAT3的磷酸化以及相应的Pim-1 mRNA表达。结论： PDGF-BB可通过Pim-1调节VSMCs增殖;STAT3可能参与了PDGF-BB诱导的VSMCs Pim-1表达。