富血小板纤维蛋白对下颌骨牵引成骨区RANKL表达的影响

目的　通过动物实验,研究应用富血小板纤维蛋白（Platelet-rich Fibrin,PRF）对兔下颌骨牵引成骨区核因子KB受体活化因子配体（receptor activator for NF-KB ligand,RANKL）的影响, 为临床研究与应用提供参考依据。 方法　在20只成年大耳白兔的一侧下颌骨前部行骨切开术,用牵引器延长一侧下颌骨4 mm,牵引间隙放置PRF膜;另一侧下颌骨行骨切开并安置牵引器,作为对照组,稳定期第1、7、14、21、28天,分别处死各组动物,取牵引区新生骨痂行组织学及RANKL免疫组化染色。 结果　下颌牵引延长后牵引间隙均有新骨形成,免疫组织化学显色RANKL主要定位于骨髓基质细胞的胞浆中,其中以稳定期的第1,14天的表达最强。在稳定期第1、14天,实验组较对照组RANKL表达的阳性细胞率及阳性面积百分比差异有统计学意义（P＜0.05）,以后逐渐下降,第28 d仅有微弱表达。 结论　动物实验表明,PRF能促进兔下颌骨牵引成骨区新骨的生成,RANKL可能在牵引成骨过程中特别是调控组织细胞应力信号传递的早期发挥破骨作用。     

Choukroun富血小板纤维蛋白复合自体微小颗粒骨修复兔颅骨缺损

背景：Choukroun富血小板纤维蛋白与自体微小颗粒骨具有促进骨缺损修复的能力,但单独应用均有其不足,拟将两种材料结合使用以期达到理想效果。 目的：观察Choukroun富血小板纤维蛋白复合自体微小颗粒骨修复颅骨缺损的效果。 方法：采用自体对照方法在大耳白兔颅骨中缝两侧利用磨骨术各制备标准一致的骨缺损,即刻于一侧骨缺损处回填Choukroun富血小板纤维蛋白膜与自体微小颗粒骨混合物作为实验组,另一侧只填充Choukroun富血小板纤维蛋白膜作为对照组,术后4,6,8周行软X射线摄片与组织病理切片观察。 结果与结论：实验组骨小梁面积显著大于对照组,骨愈合程度均优于对照组,骨小梁密度、形态、新生骨质的量及结构、成骨细胞数量均优于对照组(P < 0.05或P < 0.01),说明Choukroun富血小板纤维蛋白与自体微小颗粒骨复合材料较Choukroun富血小板纤维蛋白具有更明显促进骨缺损修复的作用。     

富血小板纤维蛋白骨诱导动物模型的建立

BACKGROUND: At present, many studies have focused on platelet-rich fibrin combined with other bone substitute materials in repair of peri-implant bone defects and sinus lifting, but there is still a lack of research  about the platelet-rich fibrin alone in repair of critical-size bone defects. OBJECTIVE: To compare the effect of three kinds of bone substitutes, platelet-rich fibrin, Bio-Oss bone substitute and autogenous cancellous bone, in repair of bone defects. METHODS: Four areas of cylindrical critical bone defects with a diameter of 6.0 mm and depth of 10.0 mm were prepared in the medial femoral condyle of beagle dogs. Three areas of bone defects were implanted with autologous platelet-rich fibrin, Bio-Oss bone substitutes and autologous cancellous bone, respectively. The remaining one area of bone defect was not implanted any substance, as control group. X-ray and Micro-CT detections in bone defect area were conducted after 12 weeks of surgery. RESULTS AND CONCLUSION: (1) X-ray: the density of platelet-rich fibrin group was more higher, but still slightly lower than that of the surrounding normal bone tissue; the density of the Bio-Oss bone substitute group was more lower, but still higher than that of the surrounding bone tissues; the density of autologous cancellous bone group was more higher, which was close to that of the surrounding bone tissues; circular low-density images were visible in the control group. (2) Micro-CT: platelet-rich fibrin group was similar with the autogenous cancellous bone group, and their density was slightly lower than that of the surrounding normal bone tissues; the trabecular bone exlibited a clear regular arrangement, and no obvious interface; the Bio-Oss bone substitute group showed a high density image with clear interface; the bone defect area was still clearly visible in the control group, with a low-density image. The bone volume fraction and trabecular number in the platelet-rich fibrin and autologous cancellous bone groups were both higher than those in the Bio-Oss bone substitute group (P < 0.05). These results demonstrate that platelet-rich fibrin and autogenous cancellous bone have a similar bone repair effect.      

富血小板纤维蛋白促进兔下颌骨牵引成骨

目的:通过建立兔下颌骨牵引成骨模型,探讨富血小板纤维蛋白(PRF)在牵引成骨中的作用,为临床研究与应用提供参考依据。方法:在成年白兔的一侧下颌骨前部行骨切开术,用牵引器延长一侧下颌骨4 mm,牵引间隙放置PRF膜为实验组;另一侧下颌骨行骨切开并安置牵引器,作为对照组,分别于稳定期的第3、7、14、28天处死动物,取牵引区新生骨痂,行大体标本观察、X线影像观察、H-E切片观察,比较2组的成骨效果,并进行骨计量学分析,计算新生骨小梁面积百分比。结果:新生骨小梁面积在不同时间点的实验组均显著大于对照组。组织学观察表明,不同时间点实验组骨成熟程度均高于对照组。结论:PRF在兔下颌骨牵引成骨中具有较显著的促进成骨的作用。     

富血小板纤维蛋白对兔下颌骨牵引成骨区骨形态发生蛋白-4表达的影响

目的:探讨富血小板纤维蛋白(PRF)对牵引成骨区骨形态发生蛋白-4(BMP-4)表达的影响。方法:25只大耳白兔随机分2组,分别行双侧下颌骨皮质骨切开术,一侧下颌骨牵引间隙放置PRF膜作为实验组,对侧作为对照组,分别于稳定期第3、7、14、21、28天处死一组动物,切取牵引间隙处骨痂行H-E染色和BMP-4免疫组织化学显色,细胞图像分析仪测量牵引间隙处骨痂BMP-4表达情况。结果:下颌牵引延长后牵引间隙均有新骨形成,免疫组织化学显色显示BMP-4主要定位于成骨细胞的细胞质中。实验组在稳定期3、7、14、21 d BMP-4表达的阳性细胞率和阳性面积百分比均显著高于对照组,稳定期28 d BMP-4表达的阳性细胞率和阳性面积百分比与对照组比较差异均无统计学意义。结论:PRF能促进兔下颌骨牵引成骨区新骨的生成,BMP-4可能在牵引成骨过程中调控组织细胞应力信号传递,发挥成骨作用。     

富血小板血浆促进牵拉成骨的矿化过程

BACKGROUND: The platelet-rich plasma contains various growth factors that could enhance the regeneration of certain tissues. OBJECTIVE: To observe the effect of platelet-rich plasma on the mineralization process during distraction osteogenesis in rabbits. METHODS: Thirty-two adult Japanese white rabbits were randomly divided into four groups (n=8 per group). The upper 1/3 tibial osteotomy at the posterior limb was performed in all rabbits, and the 1 cm limb lengthening models were prepared, followed by the local injection of 500 μL platelet-rich plasma at 5, 15 and 25 days. The controls received no treatment. At 37 days after modeling, the rabbits were killed and newly formed callus was removed to undergo hematoxylin-eosin staining, and the frontal X-ray film of tibia was obtained. RESULTS AND CONCLUSION: Lane-Sandhu radiographic scoring showed that the scores in the injection groups at 15 and 25 days after modeling were obviously better than those in the control group and the injection at 5 days after modeling. Lane-Sandhu histological scoring revealed that the scores in the injected groups at 15 and 25 days after modeling were significantly higher than those in the control group and group at 5 days after modeling (P < 0.05), which highest at 25 days. These results suggest that local injection of platelet-rich plasma can promote bone mineralization during distraction osteogenesis effectively, especially in the middle period of distraction osteogenesis. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Choukroun富血小板纤维蛋白在口腔种植骨缺损中的研究与进展

背景：近年来,Choukroun富血小板纤维蛋白作为一种富含自体细胞因子和生长因子的新型生物材料,在口腔种植骨缺损的临床应用中受到了广泛关注。 目的：就富血小板纤维蛋白的实验及临床研究进展进行综述。 方法：由第一作者应用计算机检索PubMed数据库及中国期刊网全文数据库2000-01/2011-12有关富血小板纤维蛋白生物学特性、实验研究以及临床应用等方面的文章,英文检索词为“choukroun’s platelet-rich fibrin,platelet-rich plasma,dental implant,bone defect,GBR”,中文检索词为“富血小板纤维蛋白,富血小板血浆,口腔种植,骨缺损,引导骨再生”。排除重复性研究,共保留30篇文献进行综述。 结果与结论：富血小板纤维蛋白由纤维蛋白网、血小板及粒细胞等组成,是目前较为先进的一种富含成骨作用因子的血液制品。具有制备过程操作简单、不需要添加其他制剂的特点,同时还有效模拟生理状态下血凝块中纤维蛋白的形成,与人体正常血凝块中的纤维蛋白相似,并很好地避免了免疫排斥和交叉感染的发生。在实验研究及临床应用中均显示了很好的促进组织愈合的能力。加之其成本低廉、取材方便等优点,在今后的口腔种植领域将得到越来越多的关注。     

富自体浓缩生长因子膜在兔下颌骨牵张成骨中的作用北大核心

背景:富自体浓缩生长因子膜可参与调节代谢,已被用于骨缺损的重建。研究发现在牵张成骨的新骨缝附近的成骨细胞、间质细胞及骨细胞的胞质中均有骨保护素和核因子ΚB受体活化因子配体表达。目的:分析骨矫形作用的机制及富自体浓缩生长因子膜对兔下颌骨牵张成骨的促进意义。方法:随机选取24只大白兔建立兔下颌骨牵张成骨模型;对照组行左单侧下颌骨牵张成骨;实验组将富自体浓缩生长因子膜固定于牵张成骨器内侧面并且完全包绕牵张间隙,再行右单侧下颌骨牵张成骨;共延长6 mm。在固定期第1,7,14及28天分别处死动物,获取双侧下颌骨行组织学苏木精-伊红染色、免疫印迹法Western blot法和免疫组织化学检测核因子ΚB受体活化因子配体及骨保护素在新生骨中的表达情况;观察和对比两组间牵张间隙内成骨效果。结果与结论:牵引后第1,7,14天骨保护素表达的阳性细胞率和阳性面积百分比实验组均显著高于对照组(P<0.05或P<0.01);牵引后第1,14天核因子ΚB受体活化因子配体表达的阳性细胞率和阳性面积百分比实验组均显著高于对照组(P<0.05或P<0.01);Western blot法检测核因子ΚB受体活化因子配体/骨保护素比值对照组较实验组要高(P<0.01)。结果说明,富自体浓缩生长因子膜可促进兔下颌骨牵张成骨间隙内的新骨形成和矿化,说明富自体浓缩生长因子膜是促进下颌骨牵张成骨的有效手段。     

富血小板纤维蛋白诱导口腔缺损软组织的修复与再生

BACKGROUND: Insufficient oral soft tissues in the implant zone may have a negative effect on the wound healing and the aesthetic restoration in the late stage. Platelet-rich fibrin can promote the wound healing of soft tissue defects. But there is still a lack of in-depth studies on the promotion of oral soft tissue defects in animal experiments. OBJECTIVE: To compare the repairing effects of platelet-rich fibrin and collagen membrane on soft tissue defects of the hard palate in New Zealand rabbits. METHODS: Fifty-four New Zealand rabbits were randomly divided into three groups (n=14 per group): platelet-rich fibrin group, collagen membrane group and blank control group. A 5 mm-diameter circular full-thickness soft tissue defect was made in the front of the hard palate, 2 mm distant to the rear maxillary incisors and mucosal edge of the bilateral hard palates. Autologous platelet-rich fibrin membrane or collagen membrane were implanted into the defect in the platelet-rich fibrin group and collagen membrane group, respectively. No treatment was given in the blank control group. General observation of the wound and wound healing analysis were performed at days 3, 7, 14, 21, 28, 56 post operation. Hematoxylin-eosin staining, CD31 immunohistochemical staining and Masson staining were used to observe inflammatory reaction, angiogenesis and collagen formation in the surgical site. RESULTS AND CONCLUSION: The wound healing rate was fastest in the platelet-rich fibrin group, and no obvious scar formed. At 3 days post operation, there was no difference in the wound healing rates among the three groups; at 7 days, the wound healing rate in the platelet-rich fibrin group was significantly higher than that in the collagen membrane group and blank control group (P < 0.05). At 3 and 7 days after operation, the inflammatory reaction in the platelet-rich fibrin group was less than that in the collagen membrane and blank control groups (P < 0.05); at 14, 21, 28 and 56 days, there was no significant difference between the three groups. At 7, 14, 21 days after operation, the average absorbance value of CD31 in the platelet-rich fibrin group was significantly higher than that in the collagen membrane and blank control groups (P < 0.05). The average absorbance value of collagen formation in the platelet-rich fibrin group was significantly higher than that in the collagen membrane and blank control groups at 7 days after operation (P < 0.05), significantly higher than that in the blank control group at 14 days (P < 0.05), but lower than that in the collagen membrane and blank control groups at 21, 28 and 56 days after operation (P < 0.05). These findings show that platelet-rich fibrin can reduce inflammatory reactions in the process of wound healing, accelerate the angiogenesis, regulate the metabolism of collagen, reduce the formation of scar and improve the quality of wound healing, thereby promoting the repair of oral soft tissue defects. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Enzymatically induced mineralization of platelet-rich fibrin

Membranes of the autologous blood-derived biomaterial platelet-rich fibrin (PRF) were functionalized by incorporation of alkaline phosphatase (ALP), an enzyme involved in mineralization of bone, and subsequently incubated in calcium glycerophosphate (CaGP) solution to induce PRFs mineralization with calcium phosphate (CaP) to improve PRFs suitability as a material for bone replacement. Incorporated ALP retained its bioactivity and induced formation of CaP material within PRF membranes, as confirmed by SEM, EDS, FTIR, and von Kossa staining. The mass percentage attributable to CaP was quantified by lyophilization and measurement of the remaining mass fraction as well as by TGA. Cytocompatibility tests (LDH, MTT, and WST) with SAOS-2 cells showed that mineralized PRF did not release substances detrimental to cell vitality. Live/dead staining and SEM showed that mineralized PRF was colonized by cells. The results show that hydrogel biomaterials such as PRF can be mineralized through functionalization with ALP.     

自体骨髓间充质干细胞复合富血小板纤维蛋白促进拔牙窝骨愈合

BACKGROUND: Alveolar bone deficiency will not meet aesthetic and functional requirements for dental implants.OBJECTIVE: To observe the repair effect of passage 3 autologous bone marrow mesenchymal stem cells (BMSCs) and platelet-rich fibrin (PRF) on alveolar bone defects in rabbits.METHODS: Twenty-seven New Zealand rabbits were randomly divided into BMSCs/PRF group, PRF group and model group (n=9 per group). The left mandible incisors were extracted in all the rabbits under general anesthesia. BMSCs/PRF group was immediately implanted BMSCs/PRF composite into the alveolar socket, PRF group only implanted PRF, and model group implanted nothing.RESULTS AND CONCLUSION: In the model group, the alveolar crest and alveolar mucosa become sunken notably and narrowed. In the BMSCs/PRF and PRF groups, the thickness of alveolar bone wall, alveolar bone width, alveolar bone height difference, and bone mineral density were all increased, especially in the former group. In addition, the trabecular arrangement was better in the BMSCs/PRF groups than the model and PRF group. Our findings indicate that alveolar socket filling with composite of BMSCs and PRF can achieve preservation of alveolar bone width and height after tooth extraction in rabbits.   中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

Study of platelet-rich fibrin promoting endothelial cell differentiation and angiogenesis induced by transplantation of adipose-derived stem cells

Diabetic patients are characterized by long wound healing time, and adipose stem cells (ADSCs) can secrete growth factors to promote angiogenesis and improve diabetic wound healing. In this research, we attempted to interrogate the impact of platelet-rich fibrin (PRF) on ADSCs in diabetic wound healing. ADSCs were harvested from human adipose tissues and identified through flow cytometry. After pretreatment with cultured medium supplemented with different concentrations of PRF (2.5%, 5%, and 7.5%), proliferation and differentiation capacity of ADSCs were assessed by CCK-8 assay, qRT-PCR and immunofluorescence (IF), respectively. Tube formation assay measured angiogenesis. Western blot analysis analyzed expression of endothelial markers and the extracellular signal-regulated kinase (ERK) and serine/threonine kinase (Akt) pathways in PRF-induced ADSCs. The CCK-8 experiment indicated that PRF enhanced proliferation of ADSCs in dose-dependent manner, relative to normal control group. The expression of endothelial markers and the capacity of tube formation were significantly promoted by 7.5% PRF. The release of growth factors containing vascular endothelial grow factor (VEGF) and insulin-like growth factor-1 (IGF-1) from PRF was increased with the extension of detection time. When the receptors of VEGF or/and IGF-1 were neutralized, ADSCs differentiation into endothelial cells were obviously inhibited. Additionally, PRF stimulated ERK and Akt pathways, and the inhibitors of ERK and Akt attenuated PRF-induced differentiation of ADSCs into endothelial cells. In conclusion, PRF promoted endothelial cell differentiation and angiogenesis induced by ADSCs in diabetic wound healing, which appears to give guidance for treating patients.     

人引导骨再生修复颌骨缺损的组织学观察

背景：引导骨再生对于成骨的引导及成形效果在基础研究及动物实验中已得到充分肯定,但国内有关人的颌骨骨缺损后引导骨再生中新生骨的组织学观察是一个空白。 目的：应用组织学检查了解人引导骨再生修复颌骨骨缺损的成骨效果。 方法：选取引导骨再生治疗颌骨骨缺损患者19例24个部位,于治疗后6个月行种植术中,中空钻取出术区新生骨,组织学观察,评价成骨效果。 结果与结论：所取新生骨可见不同发育阶段的骨形成。近根尖段骨中主要为板层骨,而冠方新生骨主要为纤维性骨形成,内含类骨组织及软骨性骨,极少板层骨。提示人颌骨骨缺损经引导骨再生后6个月成骨效果肯定,但远期效果还有待进一步观察。     

富血小板凝胶与拔牙窝新骨形成和骨量保持

背景：富血小板血浆能否促进骨组织的修复再生存在一定的争议。 目的：研究富血小板血浆/凝胶对拔牙窝骨愈合过程中新骨形成和骨量保持的可能调节作用,探讨富血小板血浆/凝胶与骨愈合的相互关系。 方法：通过拔牙建立Beagle犬拔牙窝骨缺损模型,同期在拔牙窝导入富血小板血浆或复血小板凝胶,并设计对照组。术后2,4,8,12周分别进行大体观察、放射影像学检查、三维CT平扫+重建、组织学检查拔牙窝颊舌侧牙槽嵴高度差、CT值以及新生骨面积。 结果与结论：与富血小板血浆组和对照组比较,影像学结果表明富血小板凝胶组在第2,4,8周新骨形成的面积最大(P < 0.01);组织学结果表明富血小板凝胶组在第2,4周新骨形成面积最大(P < 0.05);在所有时间点上富血小板凝胶组颊舌侧牙槽嵴高度差值最小(P < 0.05)。在第12周,富血小板凝胶组颊舌侧牙槽嵴高度仍有2 mm差值。提示,富血小板凝胶具有促进牙槽窝早期愈合的能力,但其单独使用时促进牙槽窝骨量保持的效能有限。