骨延长患者诱导型一氧化氮合酶的表达

背景：骨延长的牵张刺激如何转变为骨质再生的生物学信息至今不明确。目的：观察骨延长患者诱导型一氧化氮合酶的动态表达。方法：单侧胫腓骨延长组患者8例,分别于手术前第3天、术后第3,7,8,11,30天、停止延长时、停止延长第3,15,30天、拆除外固定器时、拆除外固定器后30d,检测血清诱导型一氧化氮合酶水平。并设立年龄相匹配的对照组8例。结果与结论：骨延长组牵张操作开始第1天时（术后第8天）,血清诱导型一氧化氮合酶即开始升高,停止延长时达高峰,这一时段各个时相骨延长组血清诱导型一氧化氮合酶均显著高于对照组（P〈0.01）,停止延长3d时的血清诱导型一氧化氮合酶亦高于对照组（P〈0.05）。提示诱导型一氧化氮合酶的高表达是骨延长的分子生物学机制之一。     

左旋精氨酸与褪黑激素对大鼠肾脏缺血再灌注损伤的保护作用

目的:诱导型一氧化氮合酶来源的一氧化氮与内皮型一氧化氮合酶来源的一氧化氮的平衡对维持血流动力学稳定及内环境动态平衡有重要作用.观察左旋精氨酸与褪黑激素对肾脏缺血再灌注损伤中诱导型一氧化氮合酶与内皮型一氧化氮合酶的影响.方法:实验于2006-07/2007-03在中山大学医学院动物实验中心完成.①实验分组:健康雄性清洁级SD大鼠60只,体质量170～210 g,随机数字表法分为缺血再灌注组、左旋精氨酸治疗组、褪黑激素治疗组、联合治疗组,每组15只.②实验方法:建立大鼠肾脏缺血再灌注损伤模型,术前1 h各组大鼠腹腔内注射生理盐水及相应药物,每隔24 h重复注射1次,连续5d.③实验评估:观察各组术前及术后1,3,5 d血肌酐、诱导型一氧化氮合酶和内皮型一氧化氮合酶的变化规律及肾脏病理组织学的改变,并采用Paller法对术后第3天肾小管进行评分.结果:纳入大鼠60只,均进入结果分析.①血肌酐的表达:术后第1天联合治疗组水平显著低于缺血再灌注组(P＜0.05);术后第3,5天左旋精氨酸治疗组、褪黑激素治疗组与联合治疗组显著低于缺血再灌注组(P＜0.05).②内皮型一氧化氮合酶的表达:术后第3天缺血再灌注组比术前降低(P＜0.05);术后第3天和第5天左旋精氨酸治疗组、联合治疗组高于缺血再灌注组(P＜0.05).③诱导型一氧化氮合酶的表达:术后第1天缺血再灌注组与术前相比升高,第3天达到高峰,第5天仍高于术前(P＜0.05);褪黑激素治疗组、联合治疗组术后第3天与第5天明显低于缺血再灌注组(P＜0.05).④血肌酐水平与诱导型一氧化氮合酶的表达呈正相关,r=0.57,P＜0.01,与内皮型一氧化氮合酶/诱导型一氧化氮合酶呈负相关,r=-0.61,P＜0.01.⑤肾小管损伤Palller法评分:依次为联合治疗组＜褪黑激素治疗组＜左旋精氨酸治疗组＜缺血再灌注组.结论:通过调高内皮型一氧化氮合酶的表达、抑制诱导型一氧化氮合酶的表达可以减轻肾脏缺血再灌注损伤,联合应用左型精氨酸与褪黑激素即通过以上途径更有效的起到对肾脏缺血再灌注损伤的保护作用.     

大鼠小肠移植术后血清一氧化氮及小肠组织一氧化氮合酶和诱导型一氧化氮合酶活性的变化

目的:研究同种大鼠小肠移植后内源性一氧化氮、一氧化氮合酶(nitricoxidesynthase,NOS)及诱导型一氧化氮合酶(induciblenitricoxidesyn-thase,iNOS)的变化及一氧化氮与急性排斥反应的关系。方法:以大鼠小肠移植为研究对象,16只SD大鼠进行同系移植作为对照组,8只SD大鼠和8只Wistar大鼠进行同种移植作为实验组,两组移植后分别于第3,5,7天同时取血液及小肠组织,病理为常规苏木精-伊红染色观察,血清一氧化氮采用硝酸还原酶法测定,NOS和iNOS采用分光光度法测定。结果:在急性排斥反应发生的早期实验组血清一氧化氮水平与对照组比较显著升高(术后第3,5,7天t值分别为9.7900,9.0073,6.3159,P<0.01),小肠组织NOS及iNOS活性亦显著高于对照组(NOS术后第3,5,7天t值分别为5.9318,9.1237,3.0457,iNOS术后第3,5,7天t值分别为3.2008,5.4930,4.8170,P<0.01)。结论:大鼠小肠移植后NOS及iNOS变化与排斥反应相关,血清一氧化氮水平的检测可作为干预移植措施始动的指标之一。     

活血化瘀汤对骨折愈合过程中诱导型一氧化氮合酶基因表达的影响

目的:观察活血化瘀汤对骨折愈合中诱导型一氧化氮合酶mRNA表达的影响,从而调控成骨作用。方法:实验于2002-12/2004-08在华中科技大学基础学院分子生物学实验室完成。将24只SD大鼠胫骨中段闭合骨折骨髓内克氏针固定制成骨折模型,随机分为活血化瘀汤组(n=12)及生理盐水组(n=12);于骨折后4,7,14,21d收集骨痂样本,反转录聚合酶链反应测定诱导型一氧化氮合酶的mRNA表达水平。结果:24只大鼠均进入结果分析。骨折后7,14,21d所有骨痂样本诱导型一氧化氮合酶的mRNA表达增强,骨折后14d达到峰值,活血化瘀汤组与生理盐水组比较,骨折后7,14d骨痂诱导型一氧化氮合酶基因表达显著性增强(P=0.0037)。结论:活血化瘀汤可能通过增加早期大鼠骨痂诱导型一氧化氮合酶源性一氧化氮,影响骨细胞增殖功能,从而促进骨折愈合。     

脂多糖诱导帕金森病模型中炎症因子的机制

目的:探讨脂多糖诱导帕金森病大鼠模型过程中肿瘤坏死因子α、白细胞介素1β、诱导型一氧化氮合酶等细胞毒性因子的作用。方法:实验于2003-07/2004-07在中山大学附属第一医院神经科实验室进行,取35只雄性SD大鼠随机分为4组:7,14,30d组,每组10只,对照组5只。对照组不做任何处理,3个不同时间点组立体定位注射脂多糖(20μg,质量浓度5g/L)入大鼠黑质。于注射后不同时间点观察大鼠行为学改变,并采用免疫组织化学及原位杂交等方法动态观察酪氨酸羟化酶神经元、肿瘤坏死因子α、白细胞介素1β、诱导型一氧化氮合酶等的表达。结果:29只动物进入结果分析。①行为学改变:脂多糖术后7d仅表现为轻度的旋转,每30min旋转(85±13)r,至14d时旋转次数增多,每30min旋转(121±17)r,30d时达高峰,每30min旋转(295±21)r。②7,14,30d组术侧黑质酪氨酸羟化酶阳性神经元数量较正常组明显下降(P<0.001),30d组下降达高峰;正常组仅有少量或无肿瘤坏死因子α、白细胞介素1β、诱导型一氧化氮合酶的表达,术后7d各阳性神经元表达较正常组显著增多(P<0.05),术后14d表达至高峰,术后30d较14d明显下降但仍高于正常对照组,其中诱导型一氧化氮合酶阳性神经元表达于术后30d仍维持较高水平。③各组均检测到酪氨酸羟化酶mRNA表达,7,14,30d组表达     

急性缺氧大鼠肺组织病理改变和诱导型一氧化氮合酶的表达

目的:观察急性缺氧时大鼠肺组织损伤和诱导型一氧化氮合酶的分布和活性变化。方法:实验于2004-01/2005-12在齐齐哈尔医学院微形态实验室完成。取Wistar雌性大鼠40只,随机分为正常对照组,缺氧1,3,5,7d组5组,每组8只。缺氧1,3,5,7d组大鼠分别吸入氮气与大气的混合气体(氮气的体积分数为0.95、氧气为0.05)1,3,5,7d建立急性缺氧模型,缺氧每天持续2h,其余时间同正常对照组一样置于常氧下。各组在缺氧完成后进行肺组织取材,进行常规苏木精-伊红染色观察肺组织的形态变化,免疫组织化学染色观察诱导型一氧化氮合酶的染色强度分析。结果:40只大鼠进入结果分析。①苏木精-伊红染色可见缺氧5,7d组肺气肿明显,平均肺泡面积大于正常对照组[(3543.15±150.64),(3724.32±324.67),(2789.12±110.45)μm2,t=9.8913,6.6797,P<0.01]。②随着缺氧时间的延长,诱导型一氧化氮合酶的表达范围逐渐扩大,且其表达的强度也逐渐增强,缺氧5,7d组所有肺组织和肺动脉均为强阳性表达。结论:①急性缺氧可导致大鼠肺组织发生病理改变。②急性缺氧时诱导型一氧化氮合酶在肺组织的表达增多,表达的范围和强度与缺氧时间正相关,与肺组织损伤程度正相关。③诱导型一氧化氮合酶可以作为缺氧程度和肺组织损伤程度的标志之一。     

冷保存时间对大鼠原位肝移植后移植物诱导型一氧化氮合酶表达的影响

目的:探讨大鼠原位肝移植后移植物诱导型一氧化氮合酶基因随冷保存时间的延长而表达的变化。方法:实验于2004-06/2005-06在南京大学医学院附属鼓楼医院医学检验中心科研部完成。雄性SD大鼠120只。受体大鼠根据供肝保存时间的不同随机分为3组。假手术组、保存3h组、保存6h组,每组40只。在术后存活率比较中,每组为10只,超过7d为存活受体。其余受体包括假手术组分别在门静脉复流后1,3,6,12和24h麻醉状态下各处死大鼠6只,自腹主动脉取血检测血清谷丙转氨酶、谷草转氨酶。取肝脏肝中叶保存于液氮中作后续肝脏组织内的一氧化氮代谢产物、诱导型一氧化氮合酶活性、诱导型一氧化氮合酶mRNA测定。结果:120只大鼠均进入结果分析。①各组大鼠生存率:供肝保存时间3h组1周生存率大于6h组[90%(9/10),40%(4/10)]。②术后肝脏功能变化:肝功能自术后复灌开始即有谷丙转氨酶和谷草转氨酶的逐渐升高,在术后12h达到最高值,后逐渐降低,保存6h组转氨酶下降的程度较保存3h组缓慢。③肝脏组织内NO2-和NO3-浓度的变化:肝脏内NO2-和NO3-浓度在术后3h明显增高,在术后12h达到高峰,其中保存6h组明显高于假手术组和保存3h组。④肝组织中诱导型一氧化氮合酶mRNA表达:其表达随着冷冻保存时间的延长,逐渐加强,在再灌注后12h表达最明显,其后表达逐渐减弱。保存6h组表达强度及表达持续时间明显强于保存3h组。结论:冷冻保存时间的延长能够促进诱导型一氧化氮合酶的表达,加剧了过氧化亚硝酸盐的形成,导致肝脏保存再灌注损伤的进一步发展,说明诱导型一氧化氮合酶在肝脏保存再灌注损伤中扮演了重要角色。     

活血化瘀汤对骨折愈合过程中诱导型一氧化氮合酶基因表达的影响

目的：观察活血化瘀汤对骨折愈合中诱导型一氧化氮合酶mRNA表达的影响，从而调控成骨作用。方法：实验于2002-12／2004-08在华中科技大学基础学院分子生物学实验室完成。将24只SD大鼠胫骨中段闭合骨折骨髓内克氏针固定制成骨折模型，随机分为活血化瘀汤组(n=12)及生理盐水组(n=12)；于骨折后4，7，14，21d收集骨痂样本，反转录聚合酶链反应测定诱导型一氧化氮合酶的mRNA表达水平。结果：24只大鼠均进入结果分析。骨折后7，14，21d所有骨痂样本诱导型一氧化氮合酶的mRNA表达增强，骨折后14d达到峰值，活血化瘀汤组与生理盐水组比较，骨折后7，14d骨痂诱导型一氧化氮合酶基因表达显性增强(P=0．0037)。结论：活血化瘀汤可能通过增加早期大鼠骨痂诱导型一氧化氮合酶源性一氧化氮，影响骨细胞增殖功能，从而促进骨折愈合。     

CD4~+与T淋巴细胞干扰素γ/诱导型一氧化氮合酶/一氧化氮通路在脐带间充质干细胞移植治疗重症肌无力中的作用

背景:有研究表明,CD4+、干扰素γ/诱导型一氧化氮合酶/一氧化氮通路与重症肌无力的发生密切相关。目的:探讨CD4+T细胞与干扰素γ/诱导型一氧化氮合酶/一氧化氮通路在脐带间充质干细胞移植治疗重症肌无力中的作用机制。方法:建立重症肌无力大鼠模型,并进行脐带间充质干细胞经静脉移植治疗,同时设立对照组。流式细胞术检测移植后大鼠腋窝淋巴结细胞CD4+的表达,ELISA法检测其干扰素γ的表达,Griess试剂和比色法检测一氧化氮和一氧化氮合酶水平。结果与结论:移植1周后,移植组大鼠腋窝淋巴结的淋巴细胞CD4+的表达显著高于模型组(P<0.01),干扰素γ、一氧化氮及诱导型一氧化氮合酶水平显著低于模型组(P<0.01)。证实,脐带间充质干细胞移植可上调重症肌无力模型大鼠淋巴细胞CD4+的表达,并调节干扰素γ/诱导型一氧化氮合酶/一氧化氮通路,下调一氧化氮水平,以减轻机体的免疫损伤。     

缺氧诱导因子1α和诱导型一氧化氮合酶基因在缺氧性肺动脉高压大鼠发病过程中的表达

背景:关于缺氧性肺动脉高压发病过程中缺氧诱导因子1α和诱导型一氧化氮合酶在肺动脉壁内的动态变化尚需探讨。目的:观察不同缺氧时间点肺动脉壁内缺氧诱导因子1α和诱导型一氧化氮合酶基因表达,探讨其在缺氧性肺动脉高压发病机制中的作用。设计:对比观察的动物实验。单位:南华大学附属第二医院呼吸内科。材料:选用健康雄性Wistar大鼠40只,清洁级,6～8周龄,体质量(220±10)g。按随机表法分为对照组(n=8)和缺氧组(n=32),其中缺氧组又分为缺氧后3,7,14,21d4个时间点进行观察,每个时间点8只。方法:实验于2004-08/2005-12在南华大学肿瘤研究所完成。缺氧组大鼠按李启芳报道的方法进行干预。对照组大鼠置于同一室内,除不缺氧外,余同缺氧组。按照观察时间点将大鼠麻醉后,右颈外静脉插入微导管,连接多导生理记录仪,检测大鼠肺动脉平均压。将大鼠处死取出心脏称量右心室、左室加室间隔的质量,以右室肥大指数反映右心室肥厚程度。取大鼠右上肺组织,进行苏木精-伊红染色和弹性纤维染色。用病理图像分析软件测定肺动脉管壁面积/管总面积、管腔面积/管总面积、肺细小动脉中膜平滑肌细胞密度、肺细小动脉中膜厚度作为肺小血管重塑指标。对肺小血管壁缺氧诱导因子1α,诱导型一氧化氮合酶进行原位杂交和免疫组织化学检测,以肺细小动脉管壁平均吸光度值作为mRNA表达和蛋白水平的相对含量。主要观察指标:①大鼠肺动脉平均压、右心室肥厚程度和肺小血管重塑指标的变化。②缺氧诱导因子1和诱导型一氧化氮合酶的表达及其与肺动脉平均压,肺血管重塑的关系。结果:共纳入Wistar大鼠40只全部进入结果分析。①缺氧7d时肺动脉平均压明显高于对照组(P<0.05),14d达到最高水平,之后维持于此水平。②缺氧14d右心室肥大指数高于对照组(P<0.05)。③缺氧7d肺小动脉管壁增厚,管腔变窄,肺动脉管壁面积/管总面积、管腔面积/管总面积与对照组比较,差异明显(P<0.05);缺氧14d可见肺小动脉中膜和肺细小动脉中膜平滑肌细胞密度增高,肺细小动脉中膜厚度明显增加(P<0.05)。21d管腔进一步变窄,平滑肌增生明显。④缺氧诱导因子1和诱导型一氧化氮合酶mRNA的表达:对照组大鼠呈弱阳性表达;缺氧3d和7d缺氧诱导因子1αmRNA相对量无明显变化,14d时明显增高,此后维持于高水平。诱导型一氧化氮合酶mRNA在缺氧3d明显高于对照组,7d达到高峰,14d接近对照组水平,21d再次升高,但低于缺氧3d时。⑤缺氧诱导因子1α主要表达于血管内膜和中膜,而诱导型一氧化氮合酶表达涉及血管全层。诱导型一氧化氮合酶在对照组肺血管内膜和中膜均弱阳性表达,缺氧3d与对照组差异不明显,7d中膜、内膜表达明显,14d血管中膜增厚,表达增强。在血管外膜,对照组诱导型一氧化氮合酶为阴性,各缺氧组均阳性表达。⑥mPAP与肺血管重塑正相关(r=0.976,P<0.01),缺氧诱导因子1αmRNA与诱导型一氧化氮合酶蛋白正相关(r=0.927,P<0.05)。结论:缺氧诱导因子1α和诱导型一氧化氮合酶均在大鼠缺氧性肺动脉高压的发病过程中发挥作用,且缺氧诱导因子1α与诱导型一氧化氮合酶基因表达可能存在相互调控。     

Limb lengthening in automatic mode

Background. More than 5000 lengthening procedures in the upper and lower limb bones were performed at the Russian Ilizarov Scientific Centre, including 406 segments that were lengthened in automatic mode. Distraction was continuous, 24 hours a day, at a rate of 1 mm over 60 operating cycles of the autodistractor. Material and methods. Lengthening in automatic mode was used in 171 patients between the ages of 5 and 43. Monosegmental and polysegmental osteosynthesis techniques were applied. The amount of lengthening ranged from 3 to 16 cm. The mean value of lengthening by the monosegmental type of osteosynthesis was 6.1 +/- 2.0 cm, and by polysegmental techniques, 7.2 +/- 1.5 cm. The distraction forces developed in the autodistractor were also measured. In order to develop an objective opinion about the advantages of automatic distraction, we calculated the fixation index in the apparatus for one centimeter of lengthening. Results and conclusions. The fixation index was only 5-6 days/cm when using automatic distraction, but came to 22-24 days/cm by manual adjustment of lengthening. The biochemical study of bone metabolism during lengthening showed expressed activity of blood enzymes, such as alkaline and acid phosphatases, as well as large amounts of minerals in the distraction osteogenesis area.     

Distraction epiphysiolysis in the treatment of uneven limb length

Background. In view of difference of opinion regarding the clinical value of limb lengthening by epiphyseal distraction we decided to analyze our own experiences in this area. Material and methods. Our research involved 31 children, 18 girls and 13 boys ranging in age from 7 to 14 years, treated by means of epiphyseal distraction in 17 femoral and 14 tibial segments. The mean initial shortening of the leg was 6 cm. During lengthening and after its conclusion we evaluated the extent of lengthening, the quality of the regenerated bone, and the status of the growth plate. The average follow-up was 6 years. Results. The mean limb lengthening was 5 cm (range 3-8), the average duration was 110 days, with a mean time to stabilization of 48 days (range 30-106). The mean lengthening index was 42 days/cm. Conclusions. In our opinion epiphyseal distraction is a simple procedure for limb lengthening, relatively non-invasive, but requiring considerable experience on the part of the clinical staff. The maximum lengthening should not exceed 6 cm. Monitoring of the lengthening process is very important in order to guarantee good quality regenerated bone. Epiphyseal distraction should be performed just before the child completes growth.     

肢体缓慢牵伸延长过程中膝关节功能的变化规律

背景有报道肢体延长后关节活动功能障碍是最常见的并发症之一,但也有学者认为在合理的技术操作及有效的功能防护下肢体延长术后关节功能障碍完全可以避免.目的探讨兔肢体延长过程中膝关节功能变化规律,为临床工作提供实验依据.设计随机对照实验研究.单位一所军医大学医院的骨科.对象实验于2001-02/2002-06在第三军医大学实验动物中心完成.30只健康成年新西兰兔,第三军医大学实验动物中心提供.随机分为延长组及延迟观察组(停止延长3个月观察).方法各组按延长幅度不同又分别分为延长10%,20%及40%3个亚组.采用胫骨上干骺端1 mm/d速度缓慢牵伸延长术.X射线确定延长幅度及膝关节影像学变化;测定延长终止及取材时膝关节屈伸范围.主要观察指标延长前、延长终止时及延长终止3个月时兔膝关节活动度和X射线检查结果.结果①各组不同时相点膝关节软骨未见明显影像学异常.②延长组中延长20%时出现显著性膝关节屈伸功能障碍(P＜0.05),延长40%时仅为正常膝关节活动度的44.7%左右(P＜0.01);延迟观察组关节功能均有显著性改善,其中延长20%组已恢复至延长前水平,而延长40%组也较延长终止时明显改善,但仍低于延长前正常水平,为正常水平的88.5%左右(P＜0.05).结论肢体延长过程中可能出现暂时性关节功能障碍,并主要发生在大幅度延长时.虽然在延长停止后可逐渐恢复,但仍需积极防治.     

Upper leg lengthening on an intramedullary nail: a preliminary report

Current methods of treatment for anisomelia are based on distraction osteogenesis. This involves creating callus during gradual distraction using an external fixator. The lengthening of long bones by Ilizarov's method requires keeping the external fixator in place for a long period of time, which increases the risk of complications, such as pin - track infection, stiffness of the joint, misalignment, and fracture of the regenerate. In order to shorten the period during which the external fixator must remain in place, we have introduced a method which enables the external fixator to be removed when the distraction phase is completed. During the period 1999-2001 we carried out femoral lengthening in 9 patients, using a combination of external fixation and intramedullary nail. After osteotomy of the femur and fixation by intramedullary nail, an external fixator was also applied, allowing for gradual distraction. After the requisite lengthening had been obtained by distraction at the rate of 1 mm per day, the nail was locked and the external fixator was removed. The operated patients ranged in age from 13 to 23; the average age at the moment of surgery was 16,2 years. The mean femoral anisomelia was 4,5 cm (range: 2,5-8,3). In seven cases the etiology of the anisomelia was congenital, in one case avascular necrosis of the femur, and in one case a history of femur fracture. The average duration of external fixation was 11 days for 1 cm of bone lengthening. All the lengthening femurs healed without bone union complications. In 8 cases we obtained complete isomelia, wile in 1 case there remained an inequality of 6 mm due to premature callus maturation and bone union. This is turn was caused by the patient's voluntary termination of distraction in conjunction with a two-week delay in the scheduled clinical follow-up. The removal of the external apparatus upon completion of distraction made it possible to institute early rehabilitation and enabled a quick restoration of physiological mobility in the knee joint. The chief advantages of limb lengthening using an intramedullary nail are the significant reduction in the duration of external fixation, protection of the bone regenerate against fracture, and a shorter period of time for rehabilitation. The disadvantages of this method include the extended surgical procedure and the risk of nail wedging in the intramedullary canal, which prevents lengthening.     

下颌骨牵张成骨和牵张器拆除时机的评价

目的:牵张成骨是治疗颌骨畸形和骨缺损的新方法,但力学研究及由此而确立的牵张器拆除时机的研究甚少。通过建立了山羊下颌骨牵张模型,观察下颌骨牵张后的物理、机械特性,探索牵引器拆除的时间。方法:8只山羊单侧下颌骨2次/d,1mm/d,共8d,后以牵开器继续固定至4周,行放射学、组织学、骨密度及力学测试。结果:牵拉术后下颌骨成骨明显,牵拉后2周,X线示骨间隙内新骨已基本连接骨缺损,4周时骨化明显。其骨密度与正常松质骨无明显差别,极限载荷为正常侧的61%。结论:生长期山羊为一良好的下颌骨牵张模型动物,牵拉后4周可以考虑去除牵开器。     

Osteogenic growth peptide accelerates bone healing during distraction osteogenesis in rabbit tibia

Distraction osteogenesis is a valuable treatment method that allows limb lengthening or reconstruction of large bone defects. However, its major disadvantage is the long period required for the consolidation of a distraction callus. Osteogenic growth peptide (OGP) stimulates endochondral bone formation in fracture callus, but its capacity to promote regenerate ossification during distraction osteogenesis has not been evaluated. This study investigated whether intravenously administered OGP accelerated bone healing during distraction osteogenesis in 36 male New Zealand White rabbits, randomized into two groups. The treatment group received OGP (200 ng/kg body weight) in phosphate-buffered saline (PBS), intravenously, each day; the control group received PBS alone. A 15-mm lengthening of the right lower leg was performed using the method of Ilizarov. Evidence from biomechanical, histological and radiographic evaluations demonstrated that systemic OGP treatment promoted optimal new bone formation during distraction osteogenesis in this rabbit model.     

Complication, difficulties and problems in the application of distraction epiphysiolysis

Background. Limb lengthening is a very attractive procedure in orthopedic surgery, but it is connected with a significant number of complications. Among the many methods used to lengthen limbs we studied the slow stretching of the growth plate. Material and methods. Our research involved 31 children, 18 girls and 13 boys, ranging in age from 7 to 14 years (mean 11.9), in whom epiphyseal distraction was used to lengthen 17 femoral and 14 tibial segments. The mean shortening of the leg at baseline was 6 cm. A number of complications were observed during the course of lengthening, including premature closure of the growth plate, disturbances of the limb axis, infections in the vicinity of the Kirschner wires, penetration of the wires to the knee joint, and the formation of hypoplastic regenerated bone. Results. During the mean follow-up period of 6 years,the average limb lengthening was 5 cm (range 3-8 cm), the duration averaged 110 days (range 50-160 days), the stabilization time was 48 days (30-106 days), and the mean lengthening index was 42 days/cm. Conclusions. In our opinion epiphyseal distraction is simple and relative less traumatic method of limb lengthening; however, it is associated with possible serious complications.     

Distraction-resisting force during tibial diaphyseal lengthening and consolidation--a study on a rabbit model

BACKGROUND: Distraction-resisting force is generated in the soft tissues and callus during limb lengthening. Monitoring this force may offer a method of studying the behaviour of soft tissue and detecting the distraction osteogenesis related problems, and help to prevent complications. Changes in the post distraction period have not been previously investigated and there are no reports on the contribution of gastrocnemius to the distraction-resisting force. METHODS: Sixteen immature New Zealand White rabbits underwent 30% (left) tibial diaphyseal lengthening at a rate of two 0.4 mm increments per day. Using an instrumented bilateral fixator, the passive distraction-resisting force and the contribution made by gastrocnemius were measured at the end of lengthening and 5 weeks after lengthening. FINDINGS: The distraction-resisting force at the end of lengthening (mean 44 N (SD 10)) was statistically higher (p < 0.01) than that five weeks after lengthening (mean 20 N (SD 8)), so was the contribution of the gastrocnemius to the force (mean 11 N (SD 5 N) or 25% (SD 7) at the end of lengthening and 3 N (SD 1) or 13% (SD 5.2) five weeks later). INTERPRETATION: The callus rather than the surrounding muscles generates most of the passive DRF and its share of the force increased during consolidation period.     

下颌骨牵引成骨过程中基因干预对牵引区转化生长因子β1表达的影响

背景:局部基因治疗能促进牵引区新骨的生成,但关于基因治疗后对局部生长因子表达的影响目前尚不清楚。目的:观察电穿孔介导的基因治疗对兔下颌骨牵引成骨过程中转化生长因子β1表达的影响。方法:新西兰大白兔双侧下颌骨截骨后3d开始下颌骨牵引,0.8mm/d,连续牵引7d后,随机分为5组,分别在牵引区注射2μg(0.1g/L)重组质粒pIRES-hVEGF165-hBMP2、pIRES-hBMP2、pIRES-hVEGF165、空质粒pIRES及相同剂量的生理盐水。之后施加电穿孔刺激。结果与结论:免疫组织化学染色发现转化生长因子β1主要在细胞胞浆中表达,给药7d时骨端骨细胞、编织骨痂骨细胞、骨痂表面成骨细胞呈转化生长因子β1染色阳性;14d时新生成的编织骨痂骨细胞、骨痂表面成骨细胞、肉芽组织中的间质细胞、单核巨细胞、多核巨细胞转化生长因子β1染色阳性;28d时转化生长因子β1阳性细胞明显减少。其中注射重组质粒pIRES-hVEGF165-hBMP2、pIRES-hBMP2、pIRES-hVEGF165后转化生长因子β1的表达明显多于注射空质粒pIRES及生理盐水(P<0.05或P<0.01)。说明基因治疗能促进转化生长因子β1的表达,促进牵引区细胞基质的形成和新骨生成。