两种弹性模量水凝胶人工髓核对腰椎稳定性影响的比较

目的:比较两种弹性模量(3 MPa和1 MPa)的水凝胶人工髓核的生物力学特性。方法:实验于2002-12/2003-03在上海大学生物力学研究所实验室完成。实验材料:①新型改良聚乙烯醇水凝胶人工髓核,弹性模量为3 MPa和1 MPa。②新鲜青壮年腰椎脊柱标本7个(来源于自愿捐献者尸体)。实验分组:每个标本采用自身对照方法分为4组:完整髓核组、摘除髓核组、3 MPa人工髓核组、1 MPa人工髓核组。完整髓核组标本测试后,取出全部髓核组织,进行摘除髓核组的测量,然后植入人工髓核,进行3 MPa人工髓核组和1 MPa人工髓核组测试。椎间盘在WE-5液压万能试验机上进行测试,轴向载荷为0,100,200,300,400,500 N,弯曲载荷为0～5.0N·m。加载方式采用4种不同力学模拟生理状态(轴向压缩、前屈、后伸、侧屈)。实验评估:①各组椎间盘的水平膨出位移变化。②脊柱功能单元的弹性模量变化。③小关节的应变。结果:①各组椎间盘的水平膨出位移变化:生理载荷内属于线性位移,卸载后能恢复原状。在载荷作用下,摘除髓核组和1 MPa人工髓核组膨出位移大于完整髓核组,差异均有显著性意义[分别为(1.10±0.14),(0.91±0.12),(0.80±0.10)mm,t=14.55,12.43,P<0.05],3 MPa人工髓核组椎间盘的膨出与完整髓核组相近,差异无显著性意义(P>0.05)。②脊柱功能单元的弹性模量变化:摘除髓核组和1 MPa人工髓核组弹性模量均明显低于完整髓核组[分别为(1.085±0.102),(1.317±0.157),(3.628±0.201)MPa,t=18.48,14.07,P<0.05],3 MPa人工髓核组弹性模量略低于完整髓核组,差异无显著性意义(P>0.05)。③小关节的应变:摘除髓核组和1 MPa人工髓核组小关节的应变比完整髓核组分别增加45.0%,10.7%,差异有显著性意义(P<0.05)。3 MPa人工髓核组小关节的应变比完整髓核组略大,平均相差3.7%左右,比较接近于正常(P>0.05)。结论:人工髓核置换可纠正椎间盘摘除后的生物力学紊乱,弹性模量为3 MPa的髓核假体更加适合。     

巴林特小组在综合性医院的应用实践

目的:通过综合医院开展巴林特小组活动实践,提高各科医师对患者心理问题的认知,改善职业倦怠。方法:2009年9月至2010年11月,在2所三级甲等综合医院开展了56次巴林特小组活动,共有179名医师参与,参加的医师包括不同年资(住院医师、主治医师、副主任医师、正主任医师),涵盖多个专业(内科、外科、精神科、全科、肿瘤科、急诊科、放射科、病理科),其中在上海综合医院参加者主要为负责教学的主治医师,在温州综合医院主要为全院住院医师。结果:通过巴林特小组的活动,医师们在对理解患者的感受和自己的感受、提高沟通技能等方面获得显著的感悟和提高,73.8%的医师对患者的心理问题能够识别,在医患沟通中能与家属一起沟通疾病的发展情况并给予情感支持,78.6%的医师认识并感受到自身角色对医患关系中的作用和责任,57.1%的医师能够开展比较满意的医学访谈,54.8%的医师感觉通过培训能够与那些"挑剔"的患者及其家属沟通,64.3%的医师能够做支持性的危机干预,83.0%的医师感到能够在工作中识别和处理自己的情绪压力。结论:通过巴林特小组的培训,综合医院医师对患者的心理问题认知和处理得到提高,医师自身的职业倦怠也得到一定改善,巴林特小组很适合在综合医院推广。     

酸环境对大鼠髓核细胞自噬及功能的影响

目的:观察酸环境下髓核细胞(nucleus pulposus cells,NPCs)中卵巢癌G蛋白偶联受体1(ovarian cancer G-protein-coupled receptor 1,OGR1)和自噬相关蛋白LC3的表达水平,探讨自噬激活机制,初步分析其对细胞功能的影响。方法:取SD大鼠正常髓核组织,分离培养NPCs,甲苯胺蓝、阿利新染色和Ⅱ型胶原免疫荧光检测鉴定NPCs。扩增培养NPCs,取第2代NPCs,在pH值为6.2、6.4、6.8、7.0、7.2和7.4的培养基中培养24h,免疫荧光观察NPCs中OGR1的表达情况,Western blotting检查细胞中OGR1和LC3-Ⅱ蛋白表达水平;在pH值为6.4的培养基中培养0、3h、6h、12h、24h、48h后,采用Western blotting检测NPCs中LC3-Ⅰ和LC3-Ⅱ蛋白表达水平。构建3个不同靶点的OGR1干扰序列,检测最合适滴度慢病毒,用最适滴度慢病毒转染NPCs,使用Western blotting和Real-time PCR检测不同干扰序列的沉默效果,选取最适干扰系列构建OGR1-shRNA慢病毒载体。取第2代NPCs,分为4组:正常组(DMEM培养基)、pH值6.4培养基组(空白组)、pH值6.4培养基空载体组(空载体组)、pH值6.4培养基OGR1-shRNA慢病毒转染组(转染组),培养24h后用Western blotting检测LC3-Ⅱ和p62蛋白表达水平;Alcian染色观察NPCs中蛋白多糖的表达情况。结果:(1)分离培养的细胞高表达蛋白多糖和Ⅱ型胶原,符合NPCs表型。(2)OGR1蛋白表达水平与培养基pH值相关,pH值7.0时,OGR1和LC3-Ⅱ蛋白表达水平显著性升高(P0.05),pH值6.4时表达量最高。(3)在pH值6.4的培养基中培养时,细胞中LC3-Ⅰ和LC3-Ⅱ的表达量与培养时间有关,24h时达高峰,48h仍较高。(4)3个干扰序列对OGR1均有沉默作用,与对照组比较有显著性差异(P0.05),OGR1-shRNA1沉默效果最佳。(5)转染组细胞在pH值6.4的培养基中培养24h后,LC3-Ⅱ表达水平显著性低于空载体组(P0.05);p62表达水平显著性高于空载体组(P0.05);蛋白多糖的表达低于空载体组(P0.05)。结论:酸环境可促进大鼠NPCs中OGR1蛋白表达和自噬水平升高,OGR1介导了细胞自噬的激活,并影响NPCs的生物学功能。     

磷酸镁骨粘合剂粘接骨折的实验研究

目的 探讨磷酸镁骨粘合剂（magnesium phosphate cement,MPC）粘接固定骨折的治疗效果。方法实验分为体外及体内两部分。体外部分：取54对新鲜猪股骨头标本,制备1cm^2骨折断面,随机分为6组,每组9对。分别用MPC粘接,在室温25℃和37℃、100％湿度两种不同条件下粘合固化30min,2、24h,行抗拉强度测试。体内部分：健康新西兰大白兔24只,通过开放截骨法制备兔双侧胫骨平台骨折模型。随机选取一侧为实验侧,采用MPC粘接;另一侧为对照侧,采用L形钢板内固定,术后均不作外固定。于术后3d,3、6和9周行X线片、周围血电解质、大体观察及组织学观察。结果体外部分：猪股骨头粘接体于两种不同条件下固化相同时间后其平均抗拉强度比较,差异无统计学意义（P〉0．05）。体内部分：X线片可见实验侧和对照侧骨折均于术后9周愈合,MPC随骨折愈合而逐渐被吸收。术后不同时间点周围血钙、镁浓度与术前比较,差异无统计学意义（P〉0．05）;磷浓度术后6周出现一过性升高,与术前比较差异有统计学意义（P〈0．05）。大体观察：术后3d,实验侧和对照侧均可见骨折块复位良好;3周,实验侧骨折处有部分MPC残留,对照侧可见部分骨折线;6周,实验侧骨折线消失,对照侧周围瘢痕组织和骨痂出现过度增生;9周,实验侧骨折处塑形良好,对照侧可见钢板遗留痕迹。组织学观察：实验侧术后3d,MPC与骨间界面清晰;3周,MPC开始降解,骨小梁长入其中;6周骨折愈合,仅少量MPC未吸收;9周MPC骨折愈合良好,MPC全部吸收。结论MPC的粘接强度高、能降解、对体内电解质离子浓度干扰小,是一种较为理想的骨粘合剂,可用于骨折的粘接固定。     

Recombinant human heparin- binding neurite- promoting factor express ed with yeast stimulates neurites outgrowth .

Objectives Heparin- binding neurite- promoting factor (HBNF) is a heparin- binding protein primarily found in the brain, which can stimulate neurite outgrowth in vitro.We expressed recombinant human heparin- binding neurite- promoting factor (hrHBNF) using a yeast system, and observed its activity in stimulating neurite outgrowth in vitro.Methods cDNA encoding mature human HBNF was amplified from total RNA isolated from an 18- week aborted human fetal brain by RT- PCR method.After amplification, the HBNF cDNA gene was cloned into pPIC9K, a shuttle expression vector for yeast system.The positive clone of expression vector bearing HBNF cDNA gene was obtained by screening.Verified recombinant vector was then used to transform Pichia strain GS115 by electroporation.His+ transformants were selected on minimal dextrose medium (MD) plates which were histidine free.His+ yeast recombinants with multi- copy inserts were screened in vivo by their resistance to G418.PCR analysis was used to confirm the integration of the HBNF cDNA gene into the Pichia genome.Secreted expression of hrHBNF protein in culture medium was obtained when the positive clone containing the HBNF cDNA gene was induced by methanol. The hrHBNF product purified by gel chromatography was added to cultured rat pheochromocytoma (PC12) cells to observe its ability to stimulate neurite outgrowth.Results In the recombinant expression vector, the insert was sequenced to show exactly the sequence encoding human HBNF according to Genbank data.The HBNF cDNA gene was cloned downstream to the α- factor, and its open reading frame was in frame with the α- factor signal sequence in pPIC9K.SDS- PAGE showed that the molecular weight of the induced expression product was about 18 kDa, consistent with that of human HBNF reported in the literature.The protein product did promote neurite outgrowth in cultured rat pheochromocytoma (PC12) cells.Conclusion Recombinant human heparin- binding neurite- promoting factor can be expressed with a yeast system, and its product possesses the biological activity to promote neurite outgrowth.     

自噬对椎间盘退行性变作用机制的研究进展

椎间盘退行性变（IDD）被公认为是腰痛的主要原因,约有80%的人会在其一生中遭遇到腰痛^［1］。目前,世界上约有6.5亿人受到腰痛的困扰,仅在美国,每年投入的相关费用就超过了300亿美元,甚至超过了中风、呼吸道感染、糖尿病、冠状动脉疾病及类风湿疾病的费用总和^［2］。腰痛已是导致患者住院治疗的第二大常见病因,也是导致患者长期残疾的主要原因之一^［3］。此外,IDD还是颈部和背部疼痛综合征的主要原因,严重情况下甚至会造成患者残疾^［4］。随着人口老龄化的日渐加重,IDD对人类健康造成巨大危害,也给患者家庭和社会增加了沉重的经济负担。作为一种常见的复杂退行性疾病,其传统治疗措施已无法满足目前的临床需求。自噬细胞保护效应引起学者们的关注。椎间盘髓核细胞通过自噬适应外界环境,维持细胞稳态。适度激活自噬能有效抑制椎间盘细胞凋亡,延缓细胞外基质（ECM）降解。研究自噬在IDD中的作用机制,针对性地干预其病理生理进程,可为IDD的临床治疗提供新的理念。本文通过查阅近年自噬对IDD作用的相关文献,从IDD及自噬的发生机制、髓核细胞凋亡途径及自噬对髓核细胞凋亡的作用机制等方面展开分析,综述如下。     

miRNA与肺癌顺铂耐药相关性的研究进展

 顺铂因其具有抗癌效果显著、抗癌谱广等特点,广泛应用于肺癌的临床治疗中。然而,顺铂化疗常受到内在的和获得性的耐药性的限制。越来越多的研究发现,miRNA通过调控肿瘤细胞对顺铂的转运、细胞周期、上皮细胞-间充质细胞转换和细胞凋亡等过程,与肺癌顺铂耐药存在密切联系。本文将对miRNA与肺癌顺铂耐药相关性的研究进展作一综述。     

脊柱术后静脉血栓栓塞症药物预防的研究进展

 静脉血栓栓塞症（venous thromboembolism,VTE）是骨科手术后灾难性的并发症,有较高的致死率,是患者围术期死亡以及医院内非预期死亡的重要原因之一。膝髋关节置换和髋部骨折手术后,预防性应用抗凝药物已经成为临床实践的常规。但脊柱疾病术后使用抗凝药物的意见不统一,并且脊柱术后所特有的出血并发症——硬膜外血肿,也可能会造成严重的后果。越来越多的研究发现,存在血栓高危因素的脊柱手术患者中,术后VTE的发生率很高。目前已开始尝试在脊柱术后预防性使用抗凝药物。本文通过复习相关文献,综述了近年来脊柱疾病术后VTE的发生率、危险因素、风险评估与诊断、预防措施、药物预防的作用以及并发症等研究的进展,以期能够给临床提供参考。     

胸椎黄韧带骨化症的外科治疗及疗效影响因素分析

 目的 探讨胸椎黄韧带骨化症（ossification of ligamentum flavum,OLF）的手术治疗方法及其术后疗效的影响因素。方法 回顾性分析2001年5月至2008年9月在我院进行手术治疗的39例胸椎OLF患者,其中30例采用“揭盖”式全椎板切除减压,9例采用改良后路全椎板切除减压及短节段椎弓根螺钉内固定治疗。随访术后脊髓功能恢复情况,分析术前病程、术前JOA评分（日本矫形外科学会,11分）、硬化节段、CT分型、脊髓信号改变与术后疗效的关系。结果 39例患者均获得随访,随访时间在10个月～8年,平均54个月。根据JOA评分标准进行术前和术后的疗效评价。术后疗效评价为优19例、良14例、可6例,优良率达84.6%。术前病程短,JOA评分高,单节段骨化,CT分型为外侧型及矢状位T2加权像髓内信号无改变的病例术后疗效好。结论 “揭盖”式全椎板切除减压和改良后路全椎板切除减压是治疗胸椎OLF可靠、有效的手术方式。患者术前病程、术前JOA评分、硬化节段、CT分型及压迫节段MRI示脊髓信号有无改变是影响术后疗效的主要因素。     

Prediction of traumatic avascular necrosis of the femoral head by single photon emission computerized tomography and computerized tomography: an experimental study in dogs

Objective: To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis (AVN) of the femoral head by single photon emission computerized tomography and computerized tomography (SPECT/CT). Methods: Totally 18 adult beagle dogs were divided randomly into three equal-sized (n=6) groups. Subsequently different degrees of ischemia model were developed by destroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tissues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/ CT was performed. Laser Doppler Flowmetry (LDF) measurements were also obtained at three different time points (before operation, immediately and three hours after operation) in order to assess the change process of blood supply to the femoral head. Results: SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femoral heads in Group A (t=-0.09, P=0.94) and Group B (t= 0.52, P=0.62). However, in Group C, it was 261 ±62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from (45.0±3.3) PU to (39.1±3.7) PU in Group A, from (44.0±2.7) PU to (34.3±2.6) PU in Group B, and from (47.3 ±2.1) PU to (4.96±0.6) PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C. Conclusion: SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.