天然珊瑚石人工骨在颏成形术中的应用

目的 探讨天然珊瑚石人工骨在颏成形术中的应用。方法 16例小颏畸形,采用嵌入植骨的方式将海南岛角蜂巢珊瑚石人工骨置人颏部水平截骨后的骨断面之间,观察分析其临床效果。结果 初步临床结果表明天然角蜂巢珊瑚石人工骨具有良好的组织相容性,在置入一定时间后能够被组织降解并被周围骨组织爬行替代,引导自体骨形成,所有病人对手术效果均表满意,除一过性唇颏部麻外无其它并发症发生。结论 水平截骨后采用天然角蜂巢珊瑚石人工骨嵌入植骨是矫正小颏畸形的可取方法之一。     

下颌骨外板劈开珊瑚石人工骨填充修复单侧下颌骨发育不良

目的探讨采用下颌骨外板劈开后填充珊瑚石人工骨修复重建单侧颜面短小的新方法。方法在全身麻醉下，经口内入路将下颌骨外板矢状劈开，根据术前设计需要增加的下颌骨厚度，置入相应形态和大小的珊瑚石人工骨，并采用钛钉钛板予以坚强内固定。结果采用下颌骨外板劈开填充珊瑚石人工骨的方法治疗面部畸形患者11例。随访6～18个月，1例为术后10个月时，因其他原因感染，取出珊瑚石人工骨，重新固定复位下颌骨外板后愈合；10例患者，珊瑚石人工骨与邻近骨组织结合良好，并逐渐被正常骨组织替代，面部形态得到明显改善。结论下颌骨外板矢状劈开符合下顷骨解剖学特点，并为人工骨的植入和愈合，提供了良好条件。该方法操作简单，并发症较少。是矫正单侧下颌骨发育不良的较为理想的治疗手段之一。     

新型复合人工骨成骨效应的实验研究

新型复合人工骨，ＨＡ／ＴＣＰ／ＢＭＰ为含孔块料，含孔率４０－４６％，孔径２００－４００μｍ该材料不但有一定的生物降解性能，良好的组织相容和隐固性，且具有诱导成骨作用。动物实验，经Ｘ－线，Ｙ－照像，骨密度测量及组织学检查后表明：ＨＡ／ＴＣＰ／ＢＭＰ成骨效应高于ＨＡ／ＴＣＰ，而ＨＡ／ＴＣＰ和ＨＡ／ＴＣＰ／ＢＭＰ的成骨效应都高于不具生物降解性能的ＨＡ。新型复合人工骨是一种有希望过渡于临床应用的人体硬组织     

BAM骨诱导人工骨体内植入的临床血管化DSA及3D成像研究

目的采用生物活性材料(BAM)骨诱导人工骨植入修复骨缺损并行数字减影血管造影(DSA)及三维(3D)成像,观察植入体的血供及循环重建情况。方法 12例骨缺损植骨后于术后3 d、3个月、6个月、1年在数字X线引导下,经动脉置管行植入修复部位DSA及3D成像,并对健侧同部位同时行DSA及3D成像进行对比。结果术后3个月可见有明显的从周围组织新生供应血管长入骨缺损修复区及BAM材料内,且材料植入区域血管数量较健侧多,但差异无统计学意义(P>0.05);术后6个月~1年植入骨修复材料可见更多的新生供给血管长入,血供良好,材料植入区域血管数量较健侧多(P<0.05)。结论生物活性材料植入体内后可诱发材料周围的血管长入,具有明显的血管趋化作用。     

膜内成骨与软骨成骨贴敷移植的早期血管化比较研究

目的 采用Ｗｉｓｔａｒ大鼠对颅骨（膜内成骨）和髂骨（软骨成骨）贴敷移植后早期再血管化进行了观察研究。方法 用计算机图像处理进行定量分析。结果 骨移植７天后,软骨 与膜内成骨血管密度分别为：２２．３３％和１１．８８％;１４天时分别为３４．９３％和１５．９３％。结论 软骨成骨移植后较膜内成骨有更加的血管化。文中地骨移植后骨质结构,血管化以及骨质体积存留之间的关系进行了讨论。     

一种生物陶瓷体内血管化动物模型的建立

目的建立一种新的生物陶瓷（Bioceramics）体内血管化动物模型。方法选择体重2．5～3kg的成年新西兰兔24只进行动物手术，在生物陶瓷人工骨的中轴穿入兔腰背动脉后将其包埋入兔左侧腰背筋膜内，将其作为实验组，右侧单纯埋入生物陶瓷作为对照组。术后4周、8周、12周后对人工骨材料进行切片染色、骨扫描等检查，观察人工骨血管化及骨代谢情况。结果术后4周实验组人工骨材料内出现发育成熟的血管，并开始出现新生骨和骨代谢，术后12周骨小梁发育成熟，而对照组血管化及骨化程度较差。结论中轴穿入动脉的人工骨材料埋入兔腰背筋膜后可以显著地促进人工骨的血管化。     

体外构建与体内构建组织工程骨的血管化研究

目的比较骨髓基质干细胞(BMSCs)与生物衍生骨体内、体外复合所构建的组织工程骨修复山羊胫骨大段骨-骨膜缺损的血管化进程以及血管化与成骨的关系,以探讨修复大段负重骨缺损的最佳途径。方法22只山羊制备成胫骨中段20mm的骨-骨膜缺损,随机分为2组,分别植入BMSCs与生物衍生骨体外构建和体内构建的组织工程骨,常规钢板螺钉内固定,在2、4、6、12周时间点分别用墨汁灌注透明标本、血管面积图像分析和X线片观察血管化过程及成骨情况。结果体外构建组与体内构建组血管化进程无明显区别,各时间点血管面积差异无显著性意义(P>0.05),12周均能达到完全血管化,但X线片见体外构建组新骨形成较快,缺损区密度高,体内构建组以上各变化较前者慢大约2～4周。结论BMSCs与生物衍生骨体外构建和体内构建的组织工程骨均能快速血管化并成骨,但是体内构建方式成骨较体外构建慢。     

新型生物活性陶瓷复合人工骨成骨效应的实验研究

目的　探讨新型生物活性陶瓷复合材料成骨效应 ,为人工骨替代材料临床应用提供依据。　方法　小鼠 96只 ,随机分为 4组 ,每组 2 4只。采用具有诱导活性的骨形成蛋白 (bone morphogenetic protein,BMP)分别与羟基磷灰石 (hydroxyapatite,HA)、磷酸三钙 (tricalcium phosphate,TCP)、胶原复合羟基磷灰石 (collagen HA,CHA)及氟化羟基磷灰石 (fluoridated HA,FHA)复合 ,将 4种复合材料 (HA/ BMP,TCP/ BMP,CHA/ BMP及 FHA/ BMP)分别植入 4组小鼠左侧股部肌肉内为实验侧 ,右侧分别植入 HA、TCP、CHA及脱钙牙基质 (decalcified dentin matrix,DDM)作为对照 ,在 1、3、5及 7周取材作大体观察、组织形态学、扫描电镜观察及生化测定。　结果　各组实验侧及第 4组对照侧植入后 1周软骨形成 ,第 1～ 3组对照侧为纤维结缔组织 ;3周时各组实验侧均有较多的成熟骨组织 ,组织碱性磷酸酶 (alkalinephosphatase,AL P)染色均为阳性。各组对照侧材料被结缔组织包囊 ,AL P染色阴性 ,未见骨组织形成。各组实验侧材料AL P活性及磷 (phosphrus,P)检测水平明显高于相应的对照侧材料 ,实验侧与对照侧比较具有统计学意义 (P<0 .0 5 ) ,而 TCP/ BMP复合材料明显高于另 3种复合材料 ,有统计学意义 (P<0 .0 5 )。5、7周各实验侧及对照     

一期前路手术内固定珊瑚人工骨植入治疗脊柱结核

目的 探讨脊柱结核手术治疗中一期前路病灶清除椎体间植珊瑚羟基磷灰石人工骨融合同时前路内固定手术治疗的安全性、有效性.方法 总结18例脊柱结核患者,采用一期前路病灶清除,椎体间植珊瑚羟基磷灰石人工骨融合,前路内固定器内固定治疗.结果 平均随访25个月,18例患者血沉恢复正常时间平均为术后2个月,无局部结核复发、窦道形成,植骨全部骨性融合,融合时间平均为术后5.8个月,后凸畸形矫正平均较术前纠正23.6°.神经功能全部得到显著改善.结论 脊柱结核内固定可有效纠正脊柱后凸畸形,早期重建脊柱稳定性,有助于植骨融合和减少结核复发,在结核病灶彻底清除的同时,植珊瑚羟基磷灰石人工骨是安全有效的.植骨替代材料,珊瑚羟基磷灰石人工骨的应用,避免了取自体骨带来的并发症.     

人骨髓基质干细胞与表面置换珊瑚羟基磷灰石培养的定向诱导分化

目的观察人骨髓基质干细胞（hMSC）与表面置换的珊瑚羟基磷灰石（SCHA）体外培养的细胞粘附、增殖和分化,寻找理想的骨修复材料。方法海南天然滨珊瑚在特定温度和压力下部分水热反应,制成表面置换的珊瑚羟基磷灰石,将SCHA薄片与人骨髓基质干细胞体外培养,经诱导后于4、8、12、16d分别用荧光显微镜和扫描电镜（SEM）观察细胞活性、粘附和分化过程。结果SCHA保留原有的珊瑚贯穿多孔的三维结构。荧光显微镜可见hMSC在SCHA的表面和孔道内生长良好,第16d达最高水平;电镜显示细胞粘附良好,分化为成骨细胞,分泌大量胶原纤维,可见合成的钙结节。结论hMSC在表面置换的珊瑚羟基磷灰石内粘附、增殖、分化良好,两者具有较好的生物相容性,SCHA是一种良好的骨组织工程支架材料。     

侧后方融合联合人工珊瑚椎间融合器治疗腰椎滑脱

目的　探讨侧后方融合联合人工珊瑚椎间融合器治疗腰椎滑脱的临床疗效。方法　 2 1例腰椎滑脱 ,其中L4滑脱Ⅰ°5例 ,Ⅱ°3例 ,L5滑脱Ⅰ°7例 ;Ⅱ°3例 ,L4、L5同时椎弓根不连滑脱Ⅰ°3例。平均年龄 4 8.5岁 ,采用后手术入路 ,用Steffee钢板提拉复位 ,侧后方融合联合人工珊瑚椎间融合器椎体间融合稳定脊柱。结果　随访 6～ 4 2个月 ,平均 19.1个月 ,19例术后腰痛消失 ,并感腰部稳定有力 ,18例恢复原工作与生活 ,其中有 5例术后 6个月后恢复体力劳动 ,摄腰椎正侧位片及过屈、过伸位片 ,见椎体间相对运动消失 ,椎间隙较术前平均增高 4mm ,椎间植骨已骨性模糊与上下椎体融合 ,未出现椎体再移位的并发症。结论　采用侧后方融合联合人工珊瑚椎间融合器椎体间融合吸收了前后路两种融合方法的优点 ,使融合率大大提高 ,增强了脊柱的稳定性 ,临床疗效满意。     

The release of nitroglycerin absorbed into the central venous Catheter

This study was conducted to evaluate the release of nitroglycerin (NG) that has been absorbed into the central venous catheter. A 0.05% NG solution was infused through a central venous catheter and the flow rates were set at 1, 5, or 10 ml/h, given over 12, 24, or 48 h. The catheter was flushed with lactate Ringer solution after completion of the NG infusion. The elution of the lactate Ringer solution from the tip of the catheter was then collected and assayed for its NG concentration by high performance liquid chromatography (HPLC). A higher concentration of NG was released with a faster flow rate and a longer infusion. The high level of NG release continued during the first 20 min, and ranged from a minimum of 0.07 mg/ml to a maximum that exceeded 0.15 mg/ml. Subsequently, the NG concentration gradually declined, but low concentrations of 0.006–0.02 mg/ml were still maintained 360 min later. Thus, it is suggested that if a catheter such as the Swan-Ganz continues to be used after the completion of a NG infusion, certain pharmacological effects due to the absorption of NG into the catheter body should be expected for at least 60 min.     

In vivo magnetic resonance imaging of vascularization in islet transplantation

To evaluate changes in neovascularization of transplanted islets in vivo, dynamic contrast (gadolinium) enhanced magnetic resonance imaging (MRI) was used. Both iron (Feridex)-labeled and unlabeled syngeneic murine subcapsular islet grafts were studied. Differences in dynamic contrast enhancement of islet grafts were quantified after gadolinium injection at post-transplant days 3 and 14. Normalized contrast concentrations at day 14 in transplanted islets were increased relative with that on day 3. Time to peak contrast enhancement was faster by 12 min at day 14 compared to day 3 islets (while kidney and muscle peak times remained the same). Areas under the curve for contrast concentration versus time plots were larger in 14-day relative to 3-day islet grafts. In conclusion, noninvasive assessment of neovascularization is achievable. In vivo dynamic contrast-enhanced MRI can be used to detect and quantify changes in vascularization following islet transplantation. This technique may be useful in developing pro-angiogenic strategies to improve the transplantation outcome in experimental and clinical settings.     

The effect of in vivo created vascularized neurotube on peripheric nerve regeneration

IntroductionCreating vascularized nerve conduits for treatment of nerve gaps have been researched, however, these methods need microsurgical anastomosis thereby complicating the nerve repair process. Thus, the concept of vascularized nerve conduits has not popularized up till now. The aim of this study is to evaluate the effects of vascularized and non-vascularized biological conduits on peripheral nerve regeneration.Material and methodsFollowing ethical board approval, 15 Sprague-Dawley rats were used in the study. The rats were equally divided into three groups. In group I, a silicon rod was inserted next to the sciatic nerve of the rat and connective tissue generated around this rod was used as a vascularized biological conduit. In group II, a silicon rod was inserted into the dorsum of the rat and connective tissue generated around this rod was used as a non-vascularized biological conduit. In group III, autogenic nerve graft was used to repair the nerve gap. The contralateral sciatic nerve is used as a control in all rats. Macroscopic, electrophysiological and histomorphometric evaluations were performed to determine the nerve regeneration.ResultsThere was no statistically significant difference between groups, in terms of latency. However, the mean amplitude of group I was found to be higher than other groups. The difference between group I and II was statistically significant. Myelinated axonal counts in group I was significantly higher than groups II and III.ConclusionOur results showed that vascularized biological conduits provided better nerve regeneration when compared to autografts and non-vascularized biological conduits. Creation and application of vascularized conduits by using the technique described here is easy. Although this method is not an alternative to autogenic nerve grafts, our results are promising and encouraging for further studies.     

Laser preconditioning of calvarial bone prior to an X-ray radiation injury: a preliminary in vivo study of the vascular response

BACKGROUND AND OBJECTIVES: Thermal preconditioning prior to injury induces a cytoprotective effect on soft tissues and promotes their recovery. Lasers are an adequate tool to generate controlled and reproducible heat. X-ray irradiation induces a chronic antiangiogenic effect on bone, affecting its healing and remodeling processes. The aim of this study was to investigate the effect of laser preconditioning on the re-vascularization of X-ray irradiated bone. MATERIALS AND METHODS: A bone chamber was implanted onto the calvaria of rabbits to study the vascularization process. Digital pictures were taken of the vascular plexus at the target bone site using a modified digital camera. Vascular density (VD) was determined using image processing. It was defined as the ratio of blood vessel pixels to the total number of pixels to the region of interest. Laser preconditioning was performed with a diode laser (810 nm, 2 W, 3 seconds, 48 J/cm(2), 4 mm). A 12-week follow-up study was performed on 20 rabbits divided into four groups: #1: control group (n = 5); #2: laser irradiation alone (n = 5). #3: X-ray radiation (18.75 Gy) alone (n = 5), #4: laser preconditioning 24 hours prior to X-ray radiation (n = 5). RESULTS: VD remained stable during the 12-week follow up for group #1. No significant difference was observed between laser irradiation group (#2) and control group (#1) (P>0.5). The angiolytic action of X-ray radiation was confirmed in groups #3 and #4, which were statistically different from group #1 (P<0.001). However, the decrease of the vascularization was limited in group #4 highlighting a different evolution between group #3 and #4 (P<0.05). These results were confirmed by histological analysis. DISCUSSION AND CONCLUSION: The bone chamber is an effective reproducible method for the longitudinal analysis of the dynamics of vascularization. Our findings have shown that laser preconditioning is capable of preserving vascularization in an X-ray irradiated bone site, thus suggesting a novel approach for promoting the healing of bone tissue in which the vascular supply has been damaged.     

Extended ex vivo normothermic perfusion for preservation of vascularized composite allografts

Ischemia and reperfusion injury remains a significant limiting factor for the successful revascularization of amputated extremities. Ex vivo normothermic perfusion is a novel approach to prolong the viability of the amputated limbs by maintaining physiologic cellular metabolism. This study aimed to evaluate the outcomes of extended ex vivo normothermic limb perfusion (EVNLP) in preserving the viability of amputated limbs for over 24 hours. A total of 10 porcine forelimbs underwent EVNLP. Limbs were perfused using an oxygenated colloid solution at 38°C containing washed RBCs. Five forelimbs (Group A) were perfused for 12 hours and the following 5 (Group B) until the vascular resistance increased. Contralateral forelimbs in each group were preserved at 4°C as a cold storage control group. Limb viability was compared between the 2 groups through assessment of muscle contractility, compartment pressure, tissue oxygen saturation, indocyanine green (ICG) angiography and thermography. EVNLP was performed for 12 hours in group A and up to 44 hours (24-44 hours) in group B. The final weight increase (−1.28 ± 8.59% vs. 7.28 ± 15.05%, P = .548) and compartment pressure (16.50 ± 8.60 vs. 24.00 ± 9.10) (P = .151) were not significantly different between the two groups. Final myoglobin and CK mean values in group A and B were: 875.0 ± 325.8 ng/mL (A) versus 1133.8 ± 537.7 ng/mL (B) (P = .056) and 53 344.0 ± 16 603.0 U/L versus 64 333.3 ± 32 481.8 U/L (P = .286). Tissue oxygen saturation was stable until the end in both groups. Infra-red thermography and ICG-angiography detected variations of peripheral limb perfusion. Our results suggest that extended normothermic preservation of amputated limbs is feasible and that the outcomes of prolonged EVNLP (>24 hours) are not significantly different from short EVNLP (12 hours).     

In vivo evaluation of coralline hydroxyapatite and direct current electrical stimulation in lumbar spinal fusion.

STUDY DESIGN: An animal model of posterolateral intertransverse process lumbar spinal fusion using autologous bone, coralline hydroxyapatite, and/or direct current electrical stimulation. OBJECTIVES: To evaluate the effect of an osteoconductive bone graft substitute and direct-current electrical stimulation on the rate of pseudarthrosis in a rabbit spinal fusion model. SUMMARY OF BACKGROUND DATA: Conventional techniques for the surgical treatment of degenerative conditions in the lumbar spine have a substantial failure rate and associated morbidity. Bone graft substitutes and electrical stimulation are alternative techniques to enhance fusion rates and limit the morbidity associated with posterolateral intertransverse process fusion using autologous iliac crest bone graft. METHODS: Fifty-three adult female New Zealand White rabbits underwent single-level lumbar posterolateral intertransverse process fusion. Animals were assigned to one of four groups using either autologous bone (Group I), coralline hydroxyapatite with autologous bone marrow aspirate (Group II), coralline hydroxyapatite with a 40-microA implantable direct current electrical stimulator and bone marrow aspirate (Group III), or coralline hydroxyapatite with a 100-microA implantable direct current electrical stimulator and bone marrow aspirate (Group IV). Animals were killed at 8 weeks, and fused motion segments were subjected to manual palpation, mechanical testing, and radiographic and histologic analysis to assess the fusion mass. RESULTS: Successful fusion was achieved in 57% (8/14) of animals in Group I, 25% (3/12) in Group II, 50% (6/12) in Group III, and 87% (13/15) in Group IV. Mean stiffness and ultimate load to failure were significantly higher in Group IV than in all other groups (P < 0.05). Histologic analysis demonstrated a qualitative increase in fusion mass in Group IV versus all other groups. CONCLUSIONS: Direct-current electrical stimulation increased fusion rates in a dose-dependent manner in a rabbit spinal fusion model. Coralline hydroxyapatite is an osteoconductive bone graft substitute, and thus requires an osteoinductive stimulus to ensure reliable fusion rates. Furthermore, coralline hydroxyapatite and direct current electrical stimulation can be used together to increase fusion rates in a rabbit spinal fusion model while avoiding the morbidity associated with harvesting iliac crest bone.