Binding mechanism of interface of porous coated titanium alloy prostheses

ＢｉｎｄｉｎｇｍｅｃｈａｎｉｓｍｏｆｉｎｔｅｒｆａｃｅｏｆｐｏｒｏｕｓｃｏａｔｅｄｔｉｔａｎｉｕｍａｌｌｏｙｐｒｏｓｔｈｅｓｅｓＺｏｕＨｏｎｇｅｎ（邹宏思）；ＹｅＪｕｎ（叶军）；ＴａｎｇＮｏｎｇｘｕａｎ（唐农轩）；ＹｕａｎＣｕｎｈｕａ（袁存华）（Ｄｅ...     

3D打印多孔钛金属植入物不同孔隙率对骨长入影响的实验研究

目的通过动物实验探讨3D打印多孔钛金属植入物不同孔隙率对骨长入的影响。方法18只健康新西兰兔随机分为A、B、C组,各6只。利用3D打印技术制备3种孔隙率的多孔钛板:A组35%,B组55%,C组75%,分别将多孔钛板植入兔股骨干置板区域。于术后第4、16周取股骨干标本进行X线片、大体观察和组织学观察,比较3组新生骨形成率。结果术后4周,各组钛板周围及与骨面间可见纤维组织,未见明显骨痂形成,X线片见部分钛板与骨面有间隙;术后16周,各组钛板周围及与骨面之间有新骨形成连接,个别钛板被骨痂包裹,X线片见钛板与骨面贴合紧密。组织学观察:A组钛板边缘有新骨生成,但中间孔隙内仅有少量骨组织长入;B组钛板孔隙内部分骨组织长入,但与钛板之间存在一定缝隙;C组钛板孔隙间新骨长入密度较高,且与钛板结合紧密。3组新生骨形成率差异有统计学意义（P < 0.01）,A组均明显低于B、C组（P < 0.01）,B组亦明显低于C组（P < 0.01）。结论3D打印多孔钛板的孔隙结构,可以允许新生骨长入;不同孔隙率影响3D打印钛金属植入物的新生骨长入效果,75%孔隙率较35%、55%更有利于骨长入,可与经适当处理的皮质骨表面实现良好的骨性融合。     

Distribution and change of collagen types I and III and elastin in developing leg muscle in rat

The distribution of collagen types I and III and elastin in the developing leg muscles were studied by immunohistochemistry in rat. From 0-day to 8-weeks old, the size of the gastrocnemius and plantaris muscles increased. The muscle connective tissue developed in the order of epimysium, perimysium and finally endomysium. The epimysium contained a considerable amount of collagen types I and III and some elastin in the neonates. These components in the epimysium remained almost unchanged in their distribution during development. The perimysium had little collagen type I and III or elastin at 0 day. Collagen type I and elastin slightly increased around 2 and 1 week, respectively, and returned to the previous levels. Collagen type III, however, increased and became abundant after 1 week. In the endomysium, the amounts of collagen type I and elastin were slight during postnatal growth, while collagen type III gradually increased after 2 weeks. The intramuscular tendons consistently showed intense reactivity for collagen type I and weak staining for elastin, whereas the staining for collagen type III decreased after 1 week and was finally restricted to the surface of intramuscular tendons. This study clearly demonstrated that the distribution of collagens, but not of elastin, significantly changed during development. The increase in collagen type III in the perimysium and endomysium, and its decrease in the intramuscular tendons probably reflect functional demands imposed on these connective tissues, i.e., shear forces in the former two and tensile loading in the latter.     

含天然钙化层的骨软骨材料修复猪膝关节软骨缺损

目的 构建含和不含天然钙化层的修复材料,比较两者在猪膝关节软骨缺损修复中的效果,探讨钙化层在骨软骨组织工程中的重要性.方法 选取普通实验猪膝关节骨,软骨通过Ⅱ型胶原水凝胶冻干技术和天然骨软骨脱细胞技术构建含有钙化层和无钙化层的骨软骨支架,以贵州小香猪自体骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)为种子细胞,构建移植修复材料.30只小香猪按随机数字表法分为空白对照组、无钙化层组、含钙化层组(n=10).双膝关节滑车骨软骨缺损造模,直径8 mm,深至软骨下骨,植入对应的修复材料.分别于12、24周取材,采用大体、体式显微镜观察,以及MRI检测缺损填充情况,HE染色、番红0-固绿染色,以及Ⅰ、Ⅱ型胶原蛋白免疫组化染色观察新生修复物的组织类别,O'Driscoll组织学评分评价修复效果.结果 各组术后24周修复效果较12周均有改善.大体和体式显微镜观察,24周空白对照组新生组织部分填充缺损,为纤维组织,软骨表面凹陷深大;无钙化层组移植物填充缺损,软骨表面凹陷;含钙化层组缺损填充较好,表面微凹陷,三层结构可见,与宿主组织整合佳.组织学观察提示空白对照组为纤维组织填充修复;无钙化层组为骨和纤维软骨修复,三层结构不明显;含钙化层组钙化层结构清晰,移植物与宿主整合,软骨表面微凹陷,透明软骨修复.O'Driscoll组织学评分,12、24周空白对照组分别为(3.80±0.83)、(5.50 ±0.52)分,无钙化层组分别为(10.30±0.63)、(14.20±0.68)分,含钙化层组分别为(15.10±0.58)、(18.80±0.87)分,各组评分差异均有统计学意义(P＜0.01),含钙化层组评分最高.结论 含有天然钙化层的骨软骨支架,在猪骨软骨缺损修复中取得了很好的修复效果,明显优于无钙化层支架和空白对照,是今后软骨组织工程支架设计的重要参考.     

牛骨形态发生蛋白复合微孔钛与骨界面疲劳损伤机理研究

观察微孔涂层假体与骨界面疲劳行为及影响因素，方法：将牛骨形态发生蛋白复合微孔涂层的钛合金假体植入犬股骨近侧，４，８周后取标本，干燥，在配置产皮劳台的扫描电镜下动态观察在周胶变载吓界面损伤机理。结论：微孔内骨组织改建状态对于界面疲劳损伤过程具有重要的影响。     

愈合期对微螺钉种植体-骨界面压力侧与非压力侧的影响

【目的】通过动物实验,研究不同愈合时间微螺钉种植体-骨界面颈部压力侧与非压力侧的组织学变化,探讨愈合期对颈部界面结合方式的影响。【方法】成年雄性杂种犬3只,每只犬每侧上颌颊侧骨板植入4枚种植钉,共24枚,分别进行愈合0、4、8周后加载200 g牵引力,加载8周时处死动物,取材,标记压力侧和非压力侧,两侧均制备扫描电镜标本、脱钙的HE染色标本及不脱钙的硬组织标本,后者行甲苯胺蓝及亚甲基蓝-碱性品红染色,光镜及扫描电镜下观察界面组织变化。【结果】即刻加力组颈部四周被纤维包绕,压力侧骨改建不如非压力侧活跃;愈合4周组压力侧骨改建较非压力侧活跃;愈合8周组压力侧与非压力侧骨改建较活跃,两侧差异不显著。【结论】随着愈合期的延长,无论压力侧还是非压力侧都逐渐由纤维愈合向骨性愈合转化。但即刻加力影响骨改建。     

COA: 大鼠肩关节制动后组织学和关节囊中胶原含量变化的实验研究

实验背景：临床上,肩部制动会导致肩关节粘连和关节囊挛缩伸直冻结肩,但肩部制动后的具体机制尚不清楚。本研究观察大鼠肩关节制动后盂肱关节囊、肩胛下滑囊的组织学改变以及关节囊中I/III型胶原的含量和分布的变化。 材料和方法： 46只SD大鼠随机分为1个对照组（n=6）和4个制动组（n=10）,制动组中左肩关节石膏制动1,2,3和4周。各时间点每组随机取两只鼠行盂肱关节囊连续组织学观察,III型胶原天狼星红和免疫组化观察。其它鼠用ELISA方法检测I/III型胶原在关节囊中的含量。 结果：制动2周和3周组出现前关节囊滑膜增生并阻塞于肩胛下滑囊开口处,制动3周和4周组肩胛下滑囊开始出现粘连或闭锁。制动2周组、3周组和4周组肩关节囊组织中I型和III型胶原含量增加,制动2周和3周组III型胶原分布更广泛。 结论：鼠肩制动会导致关节囊滑膜增生,肩胛下滑囊粘连和关节囊中I/III型胶原含量增加。     

骨形态发生蛋白-2基因治疗对假体-骨界面影响的实验研究

目的观察假体周围骨缺损重建中,骨形态发生蛋白(BMP)2基因治疗对假体骨界面骨整合的影响。方法14条成年Beagle犬,于双侧股骨外髁造成横向骨缺损,植入光滑面钛合金假体后保持假体周围3mm骨缺损。共28侧分成4组:空白对照组(2侧),缺损区未行处理;其余分3组为无细胞组(8侧)、细胞组(8侧)和基因组(10侧),采用压缩植骨技术重建股骨髁假体周围骨缺损,分别植入犬异体冻干骨、复合自体骨髓基质干细胞的冻干骨以及复合转BMP2基因自体骨髓基质干细胞的冻干骨。通过组织学、组织形态计量学及生物力学评估假体骨界面的愈合和整合。结果术后6周,基因组假体表面明显较多的新骨沉积,可见散在的假体与新骨间点状接触,假体骨接触率(BIC)达10%左右,而空白对照组、无细胞组和细胞组界面为厚薄不一的软组织,BIC为0;12周时,空白对照组界面仍是较厚的软组织,无细胞组和细胞组的界面主要为结缔组织纤维膜,少量点状骨接触,BIC均未超过10%,基因组的假体骨界面主要为骨组织,假体骨界面可见连续性骨接触,部分BIC达50%,远高于前两组(39.2±7.5比8.4±1.3、7.2±1.5,均P<0.01)。各组的界面推出强度随时间增加,基因组的强度在各个时间段均远高于前两组(1.40±0.22比0.09±0.04、0.08±0.04,均P<0.01)。结论BMP2基因治疗可明显提高假体骨界面的骨整合。     

Experimental Research on Ectopic Osteogenesis of BMP2-derived Peptide P24 Combined with PLGA Copolymers

To experimentally evaluate the ectopic osteogenetic capacity of synthesized BMP2-derived peptide P24 combined with poly lactic-co-glycolic acid (PLGA), Wistar rats were di- vided into two groups: group A, in which BMP2-derived peptide P24/PLGA complex was implanted, and group B which received simple PLGA implant. The complex was respectively implanted into the back muscles of rats. Samples were taken the 1st, 4th, 8th, and the 12th week after the implantation. Their bone formation was detected by X-ray examination, and tissue response was histologically ob- served. Western blotting was used for the detection of the expression of collagen Ⅰ (Col-Ⅰ) and osteopontin (OPN). There was acute inflammation in the tissue around both types of implants at early stage. The cartilage was found around implant areas 4 weeks after the implantation of BMP2-derived peptide p24/PLGA complex, 8 weeks after the implantation, osteoblasts were found, and 12 weeks after the implantation, typical trabecular bone structure was observed. In group B, after 12 weeks, no osteoblasts were found. It is concluded that PLGA is an ideal scaffold material for bone tissue engi- neering. BMP2-derived peptide can start endochondral ossification and is more effective in inducing ectopic osteogenesis.     

不同加载时机对种植体稳定性的影响

目的 探讨不同加载时机对种植体稳定性的影响.方法 将40颗种植体植入2只实验犬的双侧上、下颌骨,每只20颗.分为五组,对照组负载力值为0g,其他四组于即刻、术后2周、4周、6周加载力值200 g.测量种植体的位移情况,观察并分析种植体-骨组织界面的组织形态学变化情况.结果 40枚种植体有1枚出现Ⅰ °松动,其余39枚稳固无松动.随着加载时间的延长,种植体的平均位移逐渐缩短.不同加载时机各组的骨沉积率与对照组差异无统计学意义,不同加载时机各组的骨结合率差异无统计学意义.结论 不同加载时机会对种植体的位移距离产生一定的影响,对骨沉积率和骨结合率无明显影响,对种植体的稳定性无明显影响.     

冠状动脉旁路移植术后影响静脉移植物内膜增生因素的实验研究

目的　研究静脉移植物内膜增生机理 ,为预防静脉移植物内膜增生寻找合理有效的途径。方法　 2 4只新西兰大白兔随机分为手术组和对照组。应用半定量方法分别于术后 2周、4周检测转化生长因子 β(TGF β)、胶原Ⅰ、胶原Ⅲ和血管紧张素Ⅱ受体 1(AT1R)mRNA表达水平。 结果　手术组各检测指标在各时点均明显高于对照组 (P <0 0 1)。术后 2周时 ,TGF β(4 0 5± 0 4 9vs 2 0 5±0 2 6 ) ;AT1R(18 2 3± 1 32vs 4 6 1± 0 5 3)、胶原Ⅰ (1 80± 0 17vs 0 90± 0 18)、胶原Ⅲ (7 0 5± 0 6 8vs2 80± 0 17)各基因表达水平最高。结论　TGF β、AT1R在内膜增生中可能发挥着重要作用。持续的动脉压力作用是导致TGF β、AT1R大量表达的主要因素 ,并由此导致胶原纤维的大量合成和沉积。     

人晶状体上皮细胞Ⅰ,Ⅲ型前胶原mRNA的表达

目的 旨在从基因转录水平确定培养的人太体上皮细胞是否具有表达Ⅰ、Ⅲ型胶原的生物学特性。方法采用人眼晶状体囊膜进行晶状体上皮细胞体外的原代培养;细胞融合后,抽提ＲＮＡ,应用Ｎｏｒｔｈｅｒｎｂｌｏｔ分析技术进行探测人昌状体上皮细胞的基因转录产物。结果 人晶 状体上皮细胞的基因转录存在有Ⅰ、Ⅲ型胶胶原ｍＲＮＡ的表达,表达的二型前胶原ｍＲＮＡ均存在有长度为５．８、５．４、４．８ｋｂ的片段,Ⅰ型前胶原ｍＲＮ     

干扰素α对肝纤维化鼠星状细胞I和Ⅲ型前胶原mRNA表达及胶原？…

目的 观察干扰素α对大鼠纤维化时星状细胞增殖,Ｉ,Ⅲ型前胶原ｍＲＮＡ表达和肝脏胶原沉积的影响。方法 以ＣＣｌ４制造肝纤维化模型,培养肝星状细胞,抽提ＲＮＡ,用地高辛标记Ｉ,Ⅲ型前胶原和胶原酶ｃＤｎＡ探针,Ｎｏｒｔｈｅｒｎ杂交分析Ｉ,Ⅲ型前胶原和胶原酶ｍＲＮＡ表达,Ｄｏｔｂｌｏｔ测定大鼠肝Ｉ,Ⅲ型胶原沉积,分别用＾３Ｈ－ＴｄＲ和＾３Ｈ－脯氨酸掺入观察干扰素α对星状细胞增殖和胶原合成的影响。结果 干扰     

纳米羟基磷灰石/胶原骨修复材料

目的：制备纳米相羟基磷灰石／胶原（nano-HAp/Collagen,NHAC)复合材料,并检测骨修复性能。方法：采用仿生方法制备NHAC复合材料。结果：NHAC复合材料成分与微结构具有同天然骨类似的某些特征。复合材料的矿物含量约为50％,矿物相为含有碳酸根的羟基磷灰石,结晶度低,晶粒尺寸为纳米量级,矿物相均匀沉积在I型胶原蛋白基质上,NHAC复合材料的力学性能表现为各向同性,其显微硬度可以达到骨皮质显微硬度的下限,用颗粒型NHAC材料压制成的致密种植体植入骨髓腔后,界面层可发生溶解－再沉积的动态快速更新过程,巨噬细胞可在种植体表面或深入种植体内部通过吞噬和胞外降解方式吸收种植体材料,种植体表面及内部被吸收后,伴随有新骨的沉积,这一现象类似骨组织的重塑过程,可使NHAC种植体整合入活体骨的新陈代谢中并最终为自体现有组织所取代。结论：NHAC是生物活性材料,种植体与最组织可形成界面化学键合。     

珊瑚/胶原/重组人骨形成蛋白-2复合人工骨的异位骨诱导(英文)

目的：评价珊瑚／胶原／重组人骨形成蛋白－２ （ｒｈＢＭＰ－２）复合人工骨的骨诱导活性。　方法：将珊瑚／胶原／ｒｈＢＭＰ－２ 植入大鼠背部肌肉内,以珊瑚／胶原或珊瑚／ｒｈＢＭＰ－２ 植入作对照。术后１ 周和４周取材,通过组织学和计算机图像分析评价其异位诱导成骨情况。　结果：珊瑚／胶原／ｒｈＢＭＰ－２ 植入后１ 周,在局部诱导软骨形成;４ 周,形成含骨髓的板层骨;诱导成骨的量有明显的ｒｈＢＭＰ－２ 剂量依赖性（Ｐ＜ ０．００１）。珊瑚／胶原或珊瑚／ｒｈＢＭＰ－２ 植入区无骨或软骨形成。　结论：珊瑚／胶原／ｒｈＢＭＰ－２ 复合人工骨具有良好的异位骨诱导活性,是一种较理想的骨移植替代材料     

Effect of carvedilol on cardiac function and left ventricular remodeling in rats after acute myocardial infarction

Objective: To observe the effect of carvedilol injection on left ventricular function and collagen remodelingin rat with myocardial infarction. Methods: Sixty rats with a model of myocardial infarction were randomly divided intonine groups. The rats of therapeutical group were treated with carvedilol injection (2 mg/d intraperitoneal injection)and/or captopil (2 g/L drinking water). Acute myocardial infaction (AMI) group did not receive drug treatment. Theanimals were sacrificed at 4 weeks and 8 weeks after coronary artery ligation. The levels of plasma angiotensin Ⅱ andplasma aldosterone and left ventricle function were determined at different time. The collagen content and the raio of     

小鼠卵黄囊间质干细胞向成骨细胞定向分化的实验研究

目的研究卵黄囊间质干细胞的成骨潜能。方法用０．１％的Ⅰ型胶原酶消化获得妊娠第８．５天的小鼠卵黄囊细胞;取贴壁细胞培养,并于接近融合时进行传代培养。对细胞进行形态学观察、碱性磷酸酶（ａｌｋａｌｉｎｅ　ｐｈｏｓｐｈａｔａｓｅ,ＡＫＰ）及Ⅰ、Ⅲ型胶原检测,传代４次后进行成骨诱导,每天观察细胞形态,并于培养７ｄ后测定ＡＫＰ、Ⅰ、Ⅲ型胶原及骨形态发生蛋白－２（ｂｏｎｅ　ｍｏｒｐｈｏｇｅｎｅｔｉｃ　ｐｒｏｔｅｉｎ－２,ＢＭＰ　－２）的表达,培养８周后进行矿化检测。结果体外可获得纯化的卵黄囊间质干细胞,细胞大小形态均一,呈梭形,ＡＫＰ染色弱阳性,Ⅰ、Ⅲ型胶原阳性。在体外可诱导卵黄囊间质干细胞定向分化为多形性成骨样细胞,细胞由梭形向星形转化,并形成胞浆突起,相互连接成网状,细胞ＡＫＰ染色阳性,Ⅰ型胶原阳性,Ⅲ型胶原阴性,ＢＭＰ　－２强阳性,８周后矿化区经Ｖｏｎ　Ｋｏｓｓａ　＇ｓ染色呈阳性反应,符合成骨细胞的生物学特征。结论经体外纯化的卵黄囊间质干细胞可诱导向成骨细胞定向分化。     

Changes in myocardial collagen content before and after left ventricular assist device application in dilated cardiomyopathy

Background The purposes of this study were to confirm the changes in myocardial collagen level after left ventricular assist device (LVAD) support in dilated cardiomyopathy (DCM), find the relation between these changes and prognosis, and test a practical method to assess the level of myocardial collagen.Methods Left ventricular samples were collected from DCM patients with different prognosis (transplanted group n=8, weaning group n=10) at the time when the LVADs were implanted and again during cardiac transplantation (n=8). The level of neutral salt soluble collagen (NSC) and acid soluble collagen (ASC) was measured by Sircol collagen assay, and that of total collagen and insoluble collagen (ISC) by quantification of hydroxyproline (Hyp). Serum samples were collected from a portion of these patients (transplanted group, n=6; weaning group n=7) at the time the LVADs were implanted, 1 month after implantation and on explantation. Circulating concentration of carboxy-terminal propeptide of type Ⅰ procollagen (PⅠCP), amino-terminal propeptide of type Ⅰ procollagen (PⅠNP), amino-terminal propeptide of type Ⅲ procollagen (PⅢNP) and type Ⅰ collagen telopeptide (ⅠCTP) were measured by the equilibrium type radioimmunoassay. Results Before LVAD implantation the level of NSC and ISC in the weaning group was higher but ASC in the transplanted group was lower than in the controls (P&lt;0.05). After LVAD support, the level of total collagen was higher, but ASC was also lower in the transplanted group than in the controls (P&lt;0.05). In comparison of the pre- and post-LVAD subgroups of the transplanted and weaning groups, all collagen fraction levels before LVAD implantation were lower in the transplanted group than in the weaning group (P&lt;0.05); but this difference disappeared after LVAD support. Comparison of the pre- and post-LVAD subgroups of the transplanted group showed increased level of NSC and total collagen after LVAD support. The changes of serum peptide concentration showed that PⅢNP increased constantly in the transplanted group, but PⅠCP and PⅠNP increased in the weaning group after LVAD implantation. Conclusions The changes in myocardial collagen level as a sign of myocardial interstitial remodeling in DCM are not involved with total collagen but invalved with collagen fractions, and they are related to prognosis. The changes of myocardial collagen content and serum procollagen peptide after LVAD support can be regarded as an expression of the reverse of maladaptive myocardial interstitial remodeling.     

AD.Egr-Smad7定向基因治疗放射性肺纤维化的体内实验研究

目的通过体内实验研究,观察AD．Egr-Smad7防治C57BL小鼠放射性肺纤维化的疗效,探讨其作用机制。方法将Egr-1基因启动子的放射敏感元件和Smad7 cDNA包装到复制缺陷型腺病毒内,制备成AD．Egr-Smad7。288只小鼠随机分成6组,分别为空白对照组,单纯放射组（每日照射2次,每次8Gy,两次照射间隔8h）、AD．Egr-Smad7组,AD．Egr-Smad7放射组,病毒载体组,病毒载体放射组,各组又分为放射后0、1、2、4、8及12周小组,每小组小鼠8只。小鼠气管内给AD．Egr-Smad7、病毒载体,24h后单次全胸放射。用ELISA法检测肺组织内TGF-81、CTGF、Ⅰ型及Ⅲ型胶原含量;碱水解法测定羟脯氨酸含量;光镜下病理组织学做肺泡炎及肺纤维化镜下评分。结果γ射线照射激活Egr-1启动子调控腺病毒介导的外源性Smad7在C57BL小鼠肺内放射后1～4周内有降低TGF-B、Ⅰ型、Ⅲ型胶原及羟脯氨酸含量的作用,与对照组相比差异有统计学意义（均P〈0．01）;光镜下病理组织学改变及肺纤维化评分也证明放射激活Egr-1启动子调控外源性Smad7有降低放射后12周时肺纤维化的作用。结论放射前单次给药,经放射线诱导Egr-1启动子靶向性调控外源性Smad7基因表达,4周内在一定程度上存在阻断TGF-β信号传导通路的作用,12周时病理结果显示有定向阻断放射性肺纤维化的作用。但降低病毒载体的免疫源性及解决外源性基因持续作用问题需要进一步研究。