羟基磷灰石纳米粒子-Mg2＋对结肠癌SW480/M5细胞基因转染的效果研究

目的 探讨新型非病毒载体羟基磷灰石纳米粒子（nHAP）在肿瘤基因治疗中的作用及可能机制.方法 nHAP经氯化镁修饰后,经琼脂糖凝胶电泳判断nHAP-Mg2＋与DNA的结合和保护作用.以增强型绿色荧光蛋白真核表达载体PEGFP-N1为报告基因,以脂质体作为基因载体转染到人类结肠癌SW480/M5细胞,流式细胞术测定转染效率和平均荧光值.四甲基偶氮唑蓝（MTT）比色法评价nHAP-Mg2＋对细胞生长的影响.结果 在质量比合适时,nHAP-Mg2＋与DNA能够完全结合并对DNA起到保护作用.单独应用nHAP-Mg2＋时无基因转移功能,联合脂质体共同作为基因转染的载体可成功将PEGFP-N1基因导入SW480/M5细胞,其转染效率和平均荧光强度高于单用脂质体组（P＜0.05）.单纯应用nHAP-Mg2＋和联合脂质体时,随着nHAP-Mg2＋量的增加（0 ～ 50 μg/ml）对SW480/M5细胞的生长抑制作用增强（P＜0.05）.结论 nHAP-Mg2＋具有结合和保护质粒DNA的作用.作为脂质体的辅助载体,不但可以提高基因转染效率和稳定表达,还可增强基因治疗的抗肿瘤效果.     

钛酸钡压电陶瓷涂层的生物相容性评价

背景：课题组利用等离子喷涂技术在羟基磷灰石表面喷涂钛酸钡制备了压电陶瓷涂层,但其生物相容性尚不清楚。 目的：检测钛酸钡压电陶瓷涂层的生物相容性。 方法：①溶血实验：在兔抗凝血中分别加入受试样品浸提液、生理盐水与蒸馏水,检测溶血率。②短期全身毒性实验：对Wistar大鼠分别灌胃给予受试样品浸提液与生理盐水,观察动物体质量变化。③热源实验：自新西兰兔耳缘静脉分别注射受试样品浸提液与生理盐水,观察动物体温变化。④致敏实验：将豚鼠随机分为2组,实验组以材料浸提液与完全弗氏佐剂为供试液,对照组以生理盐水溶液与完全弗氏佐剂为供试液。按照GBT16886.10-2005医疗器械生物学评价第10 部分：刺激与迟发型超敏反应试验规定,用最大剂量法进行致敏实验。 结果与结论：受试材料钛酸钡压电陶瓷涂层无溶血作用、无毒性、不致热、无致敏作用,结果表明钛酸钡压电陶瓷涂层具有良好的生物相容性。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

髓芯减压联合纳米羟基磷灰石/聚酰胺66杆治疗股骨头坏死的前瞻性研究

目的 探讨髓芯减压联合纳米羟基磷灰石/聚酰胺66(n-HA/PA66)杆及多孔生物玻璃骨移植物治疗股骨头坏死的效果。方法 本实验为前瞻性研究。纳入西安交通大学第二附属医院骨一科2009年1月—2013年7月收治的股骨头坏死患者64例(84髋),采用信封法行简单随机分组,分为髓芯减压联合n-HA/PA66杆及多孔生物玻璃骨移植物组(治疗组,29例38髋)及髓芯减压联合自体松质骨移植组(对照组,35例46髋)。收集两组患者的临床及影像学资料,比较两组患者手术前后Harris髋关节评分(HHS)、VAS及其变化,随访终点时临床及影像学失败率,并应用生存曲线分析两组髋关节生存率。结果 两组患者术前VAS、HHS评分差异均无统计学意义(P值均>0.05);随访终点时,治疗组VAS、HHS评分均优于对照组(P值均<0.01);与术前比较,两组随访终点VAS、HHS评分有显著改善(P值均＜0.01)。两组除Steinberg ⅡB、ⅡC、ⅢA患者间术前与术后随访终点HHS评分的变化差异均有统计学意义(t=2.901、2.242、4.435,P值均＜0.05)外,其余分期两组间差异均无统计学意义(P值均>0.05)。两组除Steinberg ⅡB、ⅡC、ⅢA患者间术前与术后随访终点VAS评分的变化差异有统计学意义(t=2.933、2.119、3.513,P值均＜0.05)外,其余分期两组间差异均无统计学意义(P值均>0.05)。Kaplan-Meier生存曲线发现,在随访期内治疗组髋关节生存率高于对照组,经Log-rank检验提示两组之间髋关节生存率差异有统计学意义( χ²=6.753,P<0.05)。治疗组影像学失败率为21.05%(8/38),低于对照组的45.65%(21/46);临床失败率23.68%(9/38),亦低于对照组的52.17%(24/46);差异均有统计学意义( χ²=5.571、7.081,P值均＜0.05)。结论 髓芯减压联合n-HA/PA66杆及多孔生物玻璃骨移植物法可以显著缓解股骨头坏死患者髋关节疼痛,改善髋关节功能,并阻止股骨头塌陷。由于本手术方法对股骨头坏死治疗效果可能与其Steinberg分期有关,推荐将该方法应用于早、中期股骨头坏死患者。     

纳米羟基磷灰石/聚酰胺66复合骨髓间充质干细胞阻止股骨骨不连的形成

BACKGROUND: Orthopedists should pay more attentions to nonunion prevention in view of nonunion treatment, that is, active interventions should be taken to avoid bone delayed union and nonunion.     

丝素蛋白纳米羟基磷灰石复合材料的生物安全性

BACKGROUND: Silk fibroin has excellent biocompatibility, biodegradability and unique mechanical properties. Its composite, silk fibroin/nano-hydroxyapatite, can simulate the composition and structure of nature bone tissue, contributing to remedying the insufficient mechanical properties of nano-hydroxyapatites. OBJECTIVE: To observe the biological safety of silk fibroin/nano-hydroxyapatite composites. METHODS: Silk fibroin/nano-hydroxyapetite composite biomaterial was synthesized by the coprecipitation method using silk fibroin, calcium chloride and diammonium phosphate as raw materials. According to the demands of International Standard Organization (ISO10993) and Technical Evaluation Standards of Biomedical Materials and Medical Instruments promulgated by Chinese Board of Health (GB/T 16886), experiments of cell toxicity in vitro, acute toxicity and hemolysis were investigated to evaluate the biocompatibility of silk fibroin/nano-hydroxyapetite composite. RESULTS AND CONCLUSION: L929 cells co-cultured with silk fibroin/nano-hydroxyapatite composite leaching liquor had good cell morphology, metabolism and proliferation. The leaching extract of silk fibroin/nano-hydroxyapatite composite injected into mice intraperitoneally had no significant adverse reactions. And silk fibroin/nano-hydroxyapatite composite extracts caused 2.39% blood hemolysis, less than the international standards 5%. These experimental results on cell toxicity test in vitro, acute toxicity and hemolysis met the demands of ISO10993 and GB/T, which show the biological safety of the silk fibroin/nano-hydroxyapatite composite for clinical application.     

3D打印羊椎骨粉/聚乙烯醇支架、纳米级羟基磷灰石/聚乙烯醇支架、羊椎骨粉/聚乙烯醇无孔骨板的性能比较

BACKGROUND: With the promotion of 3D printing technology, 3D printing scaffolds for bone tissue engineering have become the new ideas for jaw bone repair. OBJECTIVE: To compare the physical and biological properties of sheep vertebral bone meal/polyvinyl alcohol (PVA) scaffold, nano-hydroxyapatite (nHA)/PVA scaffold, and sheep vertebral bone meal/PVA nonporous bone plate. METHODS: 3D printing technology was used to print sheep vertebral bone meal/PVA scaffold, nHA/PVA scaffold, and sheep vertebral bone meal/PVA nonporous bone plate. Porosity, morphology, water absorption rate and mechanical properties of different scaffolds were detected. Three kinds of scaffolds were all used to culture bone marrow mesenchymal stem cells, and cell proliferation ability was detected using cell counting kit-8 at 1, 4, 7 days of culture. RESULTS AND CONCLUSION: Under scanning electron microscope, the sheep vertebral bone meal/PVA scaffold and nHA/PVA scaffold exhibited regular and interconnected pores with good continuity and clear network structure; the sheep vertebral bone meal/PVA nonporous bone plate had no obvious pores; however, it had dense and evenly distributed micropores with different sizes on its surface. The porosity of nHA/PVA scaffold was lower than that of the sheep vertebral bone meal/PVA scaffold (P < 0.05). The water absorption rate was highest for the nHA/PVA scaffold followed by the sheep vertebral bone meal/PVA scaffold and the sheep vertebral bone meal/PVA nonporous bone plate (P < 0.05). In contrast, the scaffold toughness was highest for the sheep vertebral bone meal/PVA nonporous bone plate, followed by the sheep vertebral bone meal/PVA scaffold and nHA/PVA scaffold. In addition, the cell proliferation activity of cells cultured on the sheep vertebral bone meal/PVA scaffold was significantly higher than that cultured on the other two kinds of scaffolds. Taken together, the 3D printing sheep vertebral bone/PVA scaffold has good physical and chemical performance.     

纳米羟基磷灰石牙体修复材料的生物性能

BACKGROUND:Nanohydroxyapatite composition is similar to that of the natural bone, and because of its characteristics of nanomaterials, it has been widely used in the bone defect repair. OBJECTIVE: To observe the effect of nanohydroxyapatite composite materials in the repair of alveolar bone defect in animal models by detecting its cytotoxicity. METHODS: (1) In vitro experiment: nanohydroxyapatite extracts with concentrations of 10%, 50%, 100% (or hydroxyapatite leaching extracts) were used to culture periodontal ligament fibroblast-like cells and L-929 cells for 7 days, respectively, followed by cell cytotoxicity analysis. (2) In vivo experiment: 45 adult rabbits were used to make animal models of alveolar bone defects and then were randomized into three groups: experimental group implanted with nanohydroxyapatite, control group with hydroxyapatite, and blank control group with no implant material. New bone formation was observed at 1, 2 and 3 weeks after operation. RESULTS AND CONCLUSION: (1) In vitro experiment: after directly cultured with 10%, 50%, 100% nanohydroxyapatite extracts, the cell cytotoxicity was graded 0 to 1, indicating no presence of cytotoxicity. (2) In vivo experiment: in the three groups, the percentage of new bone area accounting for the total visual field was gradually in a rise over time. Moreover, the amount of new bone tissues was higher in the experimental group than the other two groups at different time (P < 0.05). These findings demonstrate that the nanohydroxyapatite materials have no cytotoxicity that can be used to promote the repair of alveolar bone defects.     

复合重组人骨形态发生蛋白2壳聚糖缓释水凝胶的新型HA/ZrO2多孔泡沫陶瓷人工椎体修复犬脊椎骨缺损

目的 研制复合重组人骨形态发生蛋白2(rhBMP-2)壳聚糖水凝胶的新型HA/ZrO₂多孔泡沫陶瓷人工椎体,并观察其修复beagle犬椎体骨缺损的能力。方法 离子交联法制备壳聚糖水凝胶作为rhBMP-2的缓释载体,扫描电镜下观察其微观形态,检测其载药量、包封率及缓释速率。将HA/ZrO₂多孔泡沫陶瓷人工椎体复合rhBMP-2壳聚糖水凝胶,构建新型HA/ZrO₂多孔泡沫陶瓷人工椎体。将12只beagle犬按数字表法随机分为3组,每组4只;均采用手术造成半径9 mm、高23 mm的半圆柱状L₄椎骨缺损模型,其中A组植入复合rhBMP-2壳聚糖水凝胶的新型HA/ZrO₂多孔泡沫陶瓷人工椎体,B组植入复合空白干燥壳聚糖的新型HA/ZrO₂多孔泡沫陶瓷人工椎体,C组植入实验犬自体髂骨。术后6、12、24周对实验犬行大体观察、X线影像学观察;术后24周取实验犬椎体标本行离体Micro CT新生骨量检测及生物力学检测。结果 制备所得壳聚糖水凝胶扫描电镜下呈3D网状结构,内部均匀分布壳聚糖微球,其负载rhBMP-2后包封率达91.88%±1.53%,载药量为(39.84±2.34)ng/mg;释放率第1天为28.32%±3.01%,第3天为48.92%±6.27%,第12天为74.40%±6.29%。术后6周C组动物平均活动度恢复较A组和B组快(P值均＜0.05),A、B组差异无统计学意义(P＞0.05);术后12、24周B组与C组活动度比较差异均有统计学意义(P值均＜0.05),A、C组差异均无统计学意义(P值均＞0.05)。术后6、12、24周X线影像学观察显示,A组椎体置换术后骨痂生成逐渐增多,植入材料与宿主骨之间的界线逐渐模糊,至24周时人工椎体周围新生骨与自体骨融为一体;C组在24周时出现明显非承重部位的骨吸收,出现较快的自体骨塑形;B组椎体置换术后人工椎体与自体骨的融合速度慢于A组和C组。术后24周标本Micro CT新生骨量检测结果显示,A组(145.38±18.52)mm³,B组(86.30±15.60)mm³,两组比较差异有统计学意义(t=4.879, P＜0.01)。术后24周A、B、C组手术节段椎体标本抗压强度分别为(14.03±1.67) MPa、(8.62±1.24) MPa、(13.79±1.43) MPa,A组和C组椎体极限抗压强度均高于B组(P值均＜0.01),而A组与C组比较差异无统计学意义(P＞0.05)。结论 复合rhBMP-2壳聚糖水凝胶新型HA/ZrO₂多孔泡沫陶瓷人工椎体能有效修复脊柱骨缺损,有望代替自体髂骨移植运用于临床骨缺损的修复。     

应用羟基磷灰石义眼座行眼窝充填整形术

评估眼球摘除术后应用羟基磷灰石义眼座充填进行眼窝整形的疗效。方法　采用巩膜包裹羟基磷灰石球作为眼球摘除术后眼窝整形的充填物 ,观察 15 0例眼窝充填术的效果 ,其中自体巩膜包裹羟基磷灰石球Ⅰ期植入者 10 5例 ,异体巩膜包裹羟基磷灰石球Ⅱ期植入者 45例。结果　术后并发症少 ,10 5例中除 2例因故取出 ,其余均获满意的外形和良好的义眼活动。随访 6～ 34个月 ,无植入物排出现象 ,但有 10例结膜裂开或延迟愈合 (其中 3例结膜裂开直径超过 9mm者经用人羊膜修补后愈合 ) ;1例植入物略下移 (因Ⅱ期植入时 ,下直肌未找到 )。结论　用羟基磷灰石义眼座充填适合于任何眼球摘除术后需要进行眶内植入的患者 ,没有其它人工材料制成的义眼座所常见的高排斥率及感染率。     

Evaluation of vascularization of coralline hydroxyapatite ocular implants by magnetic resonance imaging

A coralline hydroxyapatite orbital implant may be placed after ocular enucleation or evisceration. It must be vascularized to support epithelialization of a hole drilled in its anterior face for insertion of a motility peg. We used gadolinium-DTPA enhanced magnetic resonance imaging (MRI) of the orbits of two patients to assess fibrovascular penetration into their implants. MRI provides a reliable determination of implant vascularization and greater anatomic detail than 99m technetium-MDP bone scanning.