共查询到19条相似文献,搜索用时 171 毫秒
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目的 探讨Wnt/β-catenin信号通路在骨折愈合中所起的作用. 方法采用8周龄Col2al-ICAT转基因小鼠为实验组(转基因在软骨细胞中特异性表达后可竞争性阻断β-catenin信号)和同窝出生WT小鼠(对照组)作为实验动物,分别制备右下肢胫骨中段截断骨折模型.于骨折后7、9、14、21、28 d取材进行分析,通过X线片、组织学观察和组织形态计量学分析,比较两组软骨痂和骨性骨痂在骨折愈合不同时期所占的比例. 结果通过X线片观察发现,骨折后第21天,WT小鼠骨折线已消失,而Col2al-ICAT转基因小鼠骨折线仍可见.组织学观察发现,与WT小鼠相比,Col2al-ICAT转基因小鼠软骨痂出现延迟,软骨内骨化受阻,骨折的塑形改造延迟.组织形态计量学结果显示:Col2al-ICAT转基因小鼠软骨痂较晚出现高峰期,骨折后第14和第21天时骨性骨痂占总骨痂的比例明显低于WT小鼠,差异有统计学意义(P<0.05).结论 抑制Wnt/β-catenin信号通路将抑制骨折愈合的软骨内骨化过程,最终导致骨折愈合延迟. 相似文献
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作者用~(35)S-Na_2SO_4无载体溶液为示踪核素,观察了口服左旋多巴对~(35)S掺入大鼠胫骨骨折后骨痂形成不同时期的影响.结果证实:第5天、第10天,实验组~(35)S掺入骨痂量(0.11±0.02DPM%和0.19±0.05DPM%)明显大于对照组(0.08±0.02DPM%和0.13±3.05DPM%),统计学上有显著性差异(P<0.01).说明左旋多巴能促进早期骨痂对硫的利用,使外骨痂中软骨合成量增加,加快了软骨内成骨的过程.作者认为:左旋多巴促进骨折愈合作用主要是在纤维和纤维软骨骨痂形成期. 相似文献
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骨折愈合中的软骨骨痂──形态学演变及超微结构观察 总被引:2,自引:0,他引:2
通过光镜下不脱钙骨组织学、组织化学和透射电镜对雄性兔桡骨标准缺损骨折模型愈合中软骨骨痂的形成、演变及超微结构进行了观察,结果显示:软骨骨痂由骨折后进入断端间的肉芽组织分化而成,其形成和改建并不完全相同于骺板软骨内化骨。电镜下,骨痂内软骨细胞可分为5个发育阶段:成软骨细胞、软骨细胞、肥大软骨细胞、变性软骨细胞和残存软骨细胞。我们认为1)软骨骨痂由断端周围组织内的间充质细胞分化而成;2)在改建过程中,软骨骨痂能直接形成骨小梁,我们支持肥大软骨细胞能转化为骨细胞的假说;3)软骨骨痂对骨折愈合有重要的作用,能早期填充骨缺损,联接断端,是骨折在重力负载下完成愈合的基础组织之一。 相似文献
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一氧化氮调节骨折愈合的实验研究 总被引:3,自引:0,他引:3
[目的] 探讨一氧化氮在骨折愈合中的可能作用。[方法] Wistar大鼠60只随机分为实验组和对照组。两组动物的饮用水分别含L-硝基-精氨酸甲基脂(L-NAME)和D-硝基-精氨酸甲基脂(D-NAME),建立股骨开放骨折模型,骨折后第3d、1、2和4周,取每组6只大鼠骨折处骨痂行HE染色观察。另6只大鼠于骨折后4周行骨痂的面积、骨密度和骨折的生物力学评价。[结果] 骨折后两组大鼠体重增加无差别。HE染色光镜下见骨折后不同时期L-NAME组骨折处骨痂生成少,骨痂塑形慢,未成熟细胞比例较对照组多(P〈0.05),加入L-NAME后使骨折愈合反应减小,实验组骨痂的大小、骨密度和愈合强度均明显低于对照组,有明显的统计学意义。[结论] 在骨折愈合过程中加入L-NAME会使骨折愈合减慢,一氧化氮可能促进骨折的愈合过程。 相似文献
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目的探讨全身性高频率低能量振动对骨折愈合过程中软骨内成骨的促进作用。方法建立大鼠闭合性股骨骨折髓内固定模型(n=72)并随机分为治疗组和对照组。治疗组行高频率低能量振动(35Hz,峰振幅0.3重力加速度)治疗,对照组则行假治疗。治疗后1、2及4周取材行组织形态计量学和免疫组织化学研究,并采用实时荧光定量PCR对与软骨内成骨相关的基因表达进行定量研究。结果治疗组早期骨痂内的软骨成分和II型胶原表达均高于对照组。随着骨折愈合,治疗组软骨成分迅速减少,并伴有I型胶原表达的显著提升。骨形态发生蛋白-2、转化生长因子-β1和血管内皮细胞生长因子的基因表达在治疗组均得到不同程度的提升。结论高频率低能量振动可刺激软骨生成和软骨内骨化,从而促进骨折愈合中的软骨内成骨。 相似文献
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目的探讨血管内皮生长因子(VEGF)在骨折愈合中的自分泌作用。方法利用鼠股骨闭合性骨折模型,应用组织学和逆转录聚合酶链反应(RT-PCR)方法,观察骨折不同的愈合修复阶段中骨痂的组织学变化,检测各种相应骨痂组织中VEGF及其受体VEGFR1(Flt-1)和VEG-FR2(KDR/Flk-1)的mRNA的表达。结果骨折愈合是一个高度有序的组织学变化过程,骨痂内的膜内化骨,软骨形成,软骨内化骨等过程可同时或连续出现。vEGF(251bp)及受体Flt-1(272bp)和KDR/Flk-1(252bp)在骨折后第7、14天的软骨性骨痂(软骨组织)和骨性骨痂(小梁骨-膜内化骨和软骨内化骨)中均同时清晰表达。表达信号均匀,强度较大。结论骨折愈合过程中的软骨性骨痂和骨性骨痂中的软骨-骨细胞系统共表达VEGF及其两种受体,提示VEGF自分泌作用参与骨折愈合过程。 相似文献
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目的 研究鞘注神经生长因子(NGF)对大鼠胫骨骨折愈合的影响,以及相应脊髓背根神经节(DRG)与胫骨骨痂中的降钙素基因相关肽、P物质的表达变化. 方法 成年雄性SD大鼠48只随机分为两组.实验组予NGF 1μg/d连续鞘注14 d,对照组予等量生理盐水.术后7、14、21、28 d分批处死动物,行骨痂X线评分、骨痂/骨干比值测量.免疫组织化学法测定相应节段DRG与胫骨骨痂中的CGRP、SP表达.结果 术后21 d,NGF组X线评分低于对照组,21 d、28 d骨痂/骨干比值低于对照组.HE染色显示各时期NGF组软骨内成骨过程增强,骨痂成熟度高于对照组,骨痂改建过程提前且更为完全.CGRP、SP在DRG及胫骨骨痂中表达的平均光密度(OD)值高于同期对照组,差异有统计学意义(P<0.05).相关性分析显示DRG神经肽表达OD值与骨痂OD值明显正相关. 结论 鞘注神经生长因子可促进DRG与骨折骨痂中的神经肽表达,促进成骨细胞增殖与软骨内骨化,减小骨痂体积并加速骨折的愈合及塑形改建过程.推测神经生长因子与DRG神经肽参与了中枢神经调控外周成骨活动的过程. 相似文献
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低强度超声波对骨折愈合中胶原代谢影响的实验研究 总被引:6,自引:0,他引:6
目的:探讨低强度超声波对骨折愈合中Ⅰ,Ⅱ型胶原代谢的影响。方法:建立大鼠双侧胫骨近侧皮质骨缺损的动物模型,随机分为2组,实验组每日接受低强度超声波刺激,而对照组给与假刺激,于术后10,20,30天处死动物取标本(骨痂)进行组织学及免疫组化染色(SABC法),结果:组织学检查显示,实验组的血肿机化,吸收,软骨性骨痂和软骨内化骨明显早于对照组;免疫组化检查显示;实验组在20天时Ⅱ型胶原的表达明显高于对照组,在30天时I型胶原的表达也略高于对照组,结论:低强度超声波通过增加骨痂内I、Ⅱ型胶原的合成来促进骨折的愈合,其中以Ⅱ型胶原的作用尤其明显。 相似文献
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目的 通过脊髓损伤小鼠和对照组小鼠骨折愈合的对比研究来了解神经因素在骨折愈合中的作用.方法 将120只脊髓损伤小鼠(SCI)和对照组小鼠(CON)做成单侧股骨骨折模型.在术后2、4和8w,每个时间点,20只(SCI:10只,CON:10只)通过硅酮橡胶(microfil)灌注后micro-CT检查骨痂微血管,血清检测VEGF了解骨愈合过程中的血管形成的情况,检测骨钙素、碱性磷酸酶了解骨折愈合情况,同时另外20只进行骨密度,骨痂微结构分析,生物力学检测.结果 脊髓损伤小鼠骨折愈合中中血管形成情况,骨密度,骨痂微结构和生物力学都明显弱于对照组,血清VEGF、骨钙素、碱性磷酸酶也明显弱于对照组.结论 脊髓损伤明显抑制了骨折愈合,减少骨折处局部骨痂量,神经因素在骨折愈合过程中扮演着重要角色. 相似文献
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Quantitative trait locus analysis can be used to identify genes critically involved in biological processes. No such analysis
has been applied to identifying genes that control bone fracture healing. To determine the feasibility of such an approach,
healing of femur fractures was measured between C57BL/6, DBA/2, and C3H inbred strains of mice. Healing was assessed by radiography
and histology and measured by histomorphometry and biomechanical testing. In all strains, radiographic bridging of the fracture
was apparent after 3 weeks of healing. Histology showed that healing occurred through endochondral ossification in all strains.
Histomorphometric measurements found more bone in the C57BL/6 fracture calluses 7 and 10 days after fracture. In contrast,
more cartilage was present after 7 days in the C3H callus, which rapidly declined to levels less than those of C57BL/6 or
DBA/2 mice by 14 days after fracture. An endochondral ossification index was calculated by multiplying the callus percent
cartilage and bone areas as a measure of endochondral ossification. At 7 and 10 days after fracture, this value was higher
in C57BL/6 mice. Using torsional mechanical testing, normalized structural and material properties of the C57BL/6 healing
femurs were higher than values from the DBA/2 or C3H mice 4 weeks after fracture. The data indicate that fracture healing
proceeds more rapidly in C57BL/6 mice and demonstrate that genetic variability significantly contributes to the process of
bone regeneration. Large enough differences exist between C57BL/6 and DBA/2 or C3H mice to permit a quantitative trait locus
analysis to identify genes controlling bone regeneration. 相似文献
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低功率He-Ne激光照射对兔骨折愈合影响的实验研究 总被引:1,自引:0,他引:1
为探讨He-Ne激光对骨折愈合的作用,本实验用43只新西兰兔行桡骨中段截骨作为实验模型,用JG-I型医用He-Ne激光机照射骨折局部,同体对照,左侧为照射侧,右侧为对照侧,照射功率密度11.3mW/cm~2,光斑直径1.5cm,每天一次,每次10min,对照侧不作任何处理,10~60d取标本,通过X线摄片,组织学检查观察低功率,He-Ne激光照射对兔骨折愈合的影响。实验结果表明,在骨愈合的前40d,低功率He-Ne激光照射能明显促进兔新鲜骨折愈合。认为低功率He-Ne激光照射能促进骨折处血肿机化;骨折端血循环重建;加快软骨内化骨的进程;加速骨痂组织中钙盐沉积。 相似文献
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Endochondral ossification in fracture callus during long bone repair: the localisation of 'cavity-lining cells' within the cartilage. 总被引:2,自引:0,他引:2
Joanna L Ford Derek E Robinson Brigitte E Scammell 《Journal of orthopaedic research》2004,22(2):368-375
Successful fracture healing typically involves the production of a cartilaginous callus, which is eventually remodelled into new bone. The blood vessels in the advancing front of endochondral ossification are likely to play an important role in the replacement of cartilage with bone within the callus. This was investigated by histology and immunohistochemistry techniques carried out on rabbit tibial osteotomy tissue. Cavities within the cartilage were identified by histology and in many cases, there appeared to be vascular structures within them, identified by the immunolocalisation of the transmembrane proteins CD31 and CD34. Osteocalcin localisation and Alizarin red histology was carried out to identify 'osteoblastic' cells and mineral localisation within the cartilaginous callus respectively. However, it was the identification of a population of cells lining the cavities within the cartilage that became the main focus of this study. These cells were 'osteoblastic' in nature, (positive localisation of osteocalcin), and were also positive for the adhesion proteins CD31 and CD34. It is thought that these cells play a role in the conversion of cartilage to bone during the fracture healing process. 相似文献
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目的:观察丹参缓释剂植入骨折局部对骨折愈合的影响.方法:42只新西兰健康白兔随机分为两组,均于右前肢桡骨中段制成3mm骨缺损的骨折模型,同时实验组放置丹参缓释剂60mg,对照组放置等量赋形剂.分别于术后第2、4、5、6周取右桡骨行X线片及组织学检查;第2、4、6周行电镜及骨密度检查;第5、6周进行生物力学测试.结果:X线片显示实验组较对照组骨折愈合提前.组织学观察实验组纤维性骨痂、软骨性骨痂、骨小梁之间过渡加快,毛细血管增生明显.电镜检查实验组示骨折修复细胞形态学变化均有利于修复骨折.术后第2、4、6周时骨密度值实验组均较对照组高,其中第4周时两者差异具有显著性(P<0.05).术后第5、6周实验组抗折力均较对照组高(P<0.05).结论:在骨折局部使用丹参缓释剂对骨折愈合具有一定的促进作用. 相似文献
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云南白药促进骨缺损修复及引导性骨再生的实验研究 总被引:7,自引:0,他引:7
目的:阐明云南白药促进骨缺损修复及引导性骨再生的愈合机制,为临床上治疗骨折提供理论依据。方法:36只新西兰兔制作桡骨缺损不愈合模型和引导性骨再生模型,随机均分用药组及对照组,手术后3d、1、3、5、10、12周取材,观察骨痂愈合程度的差异及骨痂组织学变化,结果:实验组有明显的促进骨缺损修复作用,并在引导性骨再生中的膜内成骨作用强于对照组,结论:云南白药对骨缺损修复及引导性骨再生有明显的促进作用。 相似文献
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《BONE》2015
Parathyroid hormone-related protein (PTHrP) is widely expressed in the fibrous outer layer of the periosteum (PO), and the PTH/PTHrP type I receptor (PTHR1) is expressed in the inner PO cambial layer. The cambial layer gives rise to the PO osteoblasts (OBs) and osteoclasts (OCs) that model/remodel the cortical bone surface during development as well as during fracture healing. PTHrP has been implicated in the regulation of PO modeling during development, but nothing is known as regards a role of PTHrP in this location during fracture healing.We propose that PTHrP in the fibrous layer of the PO may be a key regulatory factor in remodeling bone formation during fracture repair. We first assessed whether PTHrP expression in the fibrous PO is associated with PO osteoblast induction in the subjacent cambial PO using a tibial fracture model in PTHrP-lacZ mice. Our results revealed that both PTHrP expression and osteoblast induction in PO were induced 3 days post-fracture. We then investigated a potential functional role of PO PTHrP during fracture repair by performing tibial fracture surgery in 10-week-old CD1 control and PTHrP conditional knockout (PTHrP cKO) mice that lack PO PTHrP. We found that callus size and formation as well as woven bone mineralization in PTHrP cKO mice were impaired compared to that in CD1 mice. Concordant with these findings, functional enzyme staining revealed impaired OB formation and OC activity in the cKO mice.We conclude that deleting PO PTHrP impairs cartilaginous callus formation, maturation and ossification as well as remodeling during fracture healing. These data are the initial genetic evidence suggesting that PO PTHrP may induce osteoblastic activity and regulate fracture healing on the cortical bone surface. 相似文献