Tissue engineering approaches for bone repair: concepts and evidence

Over the last decades, the medical world has advanced dramatically in the understanding of fracture repair. The three components needed for fracture healing are osteoconduction, osteoinduction and osteogenesis. With newly designed scaffolds, ex vivo produced growth factors and isolated stem cells, most of the challenges of critical size bone defects have been resolved in vitro, and in some cases in animal models as well. However, there are still challenges needed to be overcome before these technologies can be fully converted from the bench to the bedside. These technological and biological advancements need to be converted to mass production of affordable products that can be used in every part of the world. Vascularity, full substation of scaffolds by native bone, and bio-safety are the three most critical steps to be challenged before reaching the clinical setting.     

膝关节骨关节炎治疗的研究进展

骨关节炎（osteoarthritis，OA）是一种以关节软骨退行性改变和继发性骨增生为特征的慢性关节疾病，其中以膝关节骨关节炎（knee osteoarthritis，KOA）最为常见。目前针对KOA的非手术治疗仅能达到缓解疼痛、改善功能的目的。积极的手术治疗效果虽好，但假体定位困难，手术难度高，因此急需新的治疗方式以改善患者预后。基于KOA的最新临床研究，本文对膝神经射频消融术、机器人辅助膝关节置换术、生物治疗和激光治疗等4种新的治疗方式开展评述。     

Platelet-rich plasma improves impaired glucose hemostasis,disrupted insulin secretion,and pancreatic oxidative stress in streptozotocin-induced diabetic rat

Abstract

Our study aimed to investigate the effects of platelet-rich plasma (PRP) on impaired glucose homeostasis, disrupted islet insulin secretion, and pancreatic oxidative status in streptozotocin (STZ)-diabetic rats. A total of 64 Sprague-Dawley male were randomized to four groups including controls, diabetes, control-PRP, and diabetes-PRP. The rats received the PRP (0.5?ml/kg, SC injection) twice weekly for 4 weeks. Plasma glucose and insulin levels, pancreatic oxidative stress markers and islet insulin secretion and content were measured. Compared with the control group, in the diabetic group, increased plasma glucose and malondialdehyde (MDA) levels and decreased plasma insulin level, islet insulin secretion, pancreatic superoxide dismutase (SOD), and catalase activities were observed. PRP treatment significantly reduced plasma glucose and MDA levels and enhanced plasma insulin, antioxidant enzyme activity, islet insulin secretion, and content in the diabetic rats. These findings showed that PRP can improve pancreatic islet insulin secretion, pancreatic oxidative stress and regulate plasma insulin and glucose levels in diabetic rats.     

PRP及前列地尔对兔缺血皮瓣的影响

【摘要】 目的 探讨富血小板血浆（PRP）、前列地尔注射液及其联合应用对兔缺血皮瓣的影响。 方法 选择 40 只健康新西兰兔随机分为20组，每组2 只，每只兔背部设计两块以中线对称的 10cm×2.5cm 大小超长宽比例任意皮瓣，形成每组 4 个兔背缺血皮瓣模型。每组随机分为对照瓣及实验瓣1、试验瓣2、试验瓣3。对照瓣：采用局部及静脉均注射生理盐水；实验瓣1：局部注射 PRP，静脉注射生理盐水；试验瓣2：局部注射生理盐水，静脉注射前列地尔注射液（0.8mL/kg)；试验瓣3：局部注射 PRP，静脉注射前列地尔注射液。术后 7d 在统一标准下拍照并取材。测量各瓣存活面积，计算皮瓣存活率；HE 染色后镜下观察各瓣组织结构层次、炎性细胞浸润情况及微血管口径变化；免疫组化检测 CD34 表达、测量微血管密度；酶联免疫吸附法（ELISA）检测血管内皮生长因子（VEGF）含量。结果 术后 7d，各瓣远端均发生不同程度坏死，经测量计算后得出：各瓣平均存活面积、存活率、微血管密度、VEGF 含量由大到小依次为：实验瓣3＞实验瓣1＞实验瓣2＞对照瓣，组间比较差异有统计学意义（均P＜0.05)。HE 染色后镜下观察可见：所有实验瓣较对照瓣组织水肿轻，新生毛细血管增多；实验瓣3较对照瓣及实验瓣1、实验瓣2结构、层次更清晰分明，新生毛细血管最多，大部分管腔扩大，炎性细胞浸润较少，组织水肿轻；实验瓣1较实验瓣2组织结构分明，新生毛细血管较多，炎性细胞浸润较少，但实验瓣2血管管腔直径更大。结论 富血小板血浆、前列地尔注射液单独应用时均能不同程度改善兔缺血皮瓣缺血坏死，提高皮瓣存活率，并且二者联合应用效果优于单独使用。     

全视网膜光凝术联合雷珠单抗对糖尿病性黄斑水肿患者最佳矫正视力的影响

目的 研究全视网膜光凝术(PRP)联合雷珠单抗对糖尿病性黄斑水肿患者最佳矫正视力的治疗效果。方法125例患者(合计125只眼)被分为两组,即观察组(n=62)与对照组(n=63)。对照组接受PRP进行治疗,而观察组患者联合使用PRP与雷珠单抗进行治疗。结果相比较对照组,观察组治疗后(3个月、6个月)最佳矫正视力明显增高,视网膜新生血管渗漏面积、中心区视网膜厚度、黄斑总体积明显更低。且观察组治疗有效率明显高于对照组(90.48% vs 67.44%,P<0.05),同时无严重并发症发生。结论PRP联合雷珠单抗治疗糖尿病性黄斑水肿安全有效,值得推广。     

Combination of hydroxyapatite,platelet rich fibrin and amnion membrane as a novel therapeutic option in regenerative periapical endodontic surgery: Case series

IntroductionPeriapical surgery is the last resort in the arsenal of an endodontist to effectively deal with periapical lesions that result from necrosis of the pulp. Bone grafts, growth factors and membranes form an array of regenerative materials that influence the healing outcome of periapical surgery.Presentation of caseThe main purpose of the two cases reported here was to assess the potential benefits of a combination of bone graft, platelet-rich fibrin (PRF) and amnion membrane in terms of reduced post-operative discomfort, radiographic evidence of accelerated periapical bone healing and present a novel therapeutic option in the management of large periapical lesions. Two cases of radicular cysts were treated through a combined regenerative approachof Bio-Gen mix^®, PRF and amnion membrane. The patients were assessed for discomfort immediate post-operatively and after a week. The patients were recalled every month for the next 6 months for radiographic assessment of the periapical healing.DiscussionLiterature is replete with articles that have substantiated the role of demineralized bone matrix comprising a mixture of cancellous and cortical bone graft particles in enhancing regeneration. To the best of our knowledge, there has been no evidence related to the application of a human placental membrane in periapical surgery. Hence, the rationale of using a combined approach of Bio-Gen mix^®, PRF and amnion membrane was to combine the individual advantages of these materials to enhance clinical and radiographic healing outcomes. Our present case reports provide an insight into this novel therapeutic option.ConclusionThe results of this case seriessubstantiatesthe credibility of using a combination ofamnion membrane with a bone graft and PRF to enhance radiographic healing outcome with decreased post-operative discomfort and present a viable regenerative treatment modality in periapical surgery.