Fabrication of a Layered Microstructured Polymeric Microspheres as a Cell Carrier for Nucleus Pulposus Regeneration

Abstract

This study aimed to investigate the feasibility of nanostructured 3D poly(lactide-co-glycolide) (PLGA) constructs, which are loaded with dexamethasone (DEX) and growth factor embedded hepaiin/poly(L-lysine) nanoparticles by a layer-by-layer system, to serve as an effective scaffold for nucleus pulposus (NP) tissue engineering. Our results demonstrated that the microsphere constructs were capable of simultaneously releasing basic fibroblast growth factor and DEX with approximately zero-order kinetics. The dual bead microspheres showed no cytotoxicity, and promoted the proliferation of the rat mesenchymal stem cells (rMSCs) by lactate dehydrogenase assay and CCK-8 assay. After 4 weeks of culture in vitro, the rMSCs- scaffold hybrids contained significantly higher levels of sulfated GAG/DNA and type-II collagen than the control samples. Moreover, quantity real-time PCR analysis revealed that the expression of disc-matrix proteins, including type-II collagen, aggrecan and versican, in the rMSCs-scaffold hybrids was significantly higher than the control group, whereas the expression of osteogenic differentiation marker type-I collagen was decreased. Taken together, these data indicate that the heparin bound bFGF-coated and DEX-loaded PLGA microsphere constructs is an effective bioactive scaffold for the regeneration of NP tissue.     

Vascularization into a porous sponge by sustained release of basic fibroblast growth factor

Vascularization into a poly(vinyl alcohol) (PVA) sponge was investigated using basic fibroblast growth factor (bFGF). This growth factor was impregnated into biodegradable gelatin microspheres for its sustained release and then the bFGF-containing microspheres or free bFGF were incorporated into PVA sponges. Following subcutaneous implantation into the back of mice, the bFGF-containing gelatin microspheres induced vascularization in and around the sponge to a significantly greater extent than that of free bFGF from 3 days after implantation. Significant ingrowth of fibrous tissue into the sponge was also observed when bFGF-containing microspheres were added to the sponge in contrast to free bFGF. Tissue ingrowth occurred into the deeper portion of the sponge over time while it accompanied formation of new capillaries. Empty gelatin microspheres had no effect on vascularization and the level of fibrous tissue ingrowth into the sponge was similar to that of the control group. It was concluded that incorporation of gelatin microspheres containing bFGF into the PVA sponge was effective in prevascularization of the sponge pores.     

单环刺缢及同种异体神经制成人工神经修复神经缺损

目的:研究去细胞的单环刺缢体壁和同种异体神经所构成的人工组织神经的组织相容性及其修复神经缺损的效果。方法:取大鼠40只随机分成实验组、自体神经组、硅胶管组、正常组。实验组将去细胞的单环刺缢体壁缝合成神经导管,其内充填去细胞的异体神经,修复大鼠10 mm坐骨神经缺损。术后4月,通过大体观察,组织形态学观察,了解该人工组织神经修复大鼠坐骨神经缺损的疗效。结果:该人工组织神经组织相容性良好,神经功能恢复效果正常组>自体神经组>实验组>硅胶管组,实验组疗效与自体神经组接近,明显优于硅胶管组。结论:将去细胞的单环刺缢体壁和同种异体神经制成人工组织神经修复周围神经缺损是可行的。     

E003对RSA模型小鼠蜕膜组织超微结构的影响

目的　观察瑞香素（daphnetin）即E003处理后RSA模型小鼠蜕膜组织形态结构的改变。 方法　建立反复自然流产（recurrent spontaneous abortion,RSA）模型小鼠后,实验分正常妊娠组、RSA模型组、E003低剂量组和E003高剂量组共4组,E003连续灌胃处理14 d后,取蜕膜组织。光镜下观察蜕膜组织血管和细胞形态,电镜下观察蜕膜组织超微结构。 结果　解剖子宫计算胚胎吸收率,E003处理组（低剂量组和高剂量组）低于RSA模型组,差异具有统计学意义,P<0.05;E003高剂量组胚胎吸收率与正常妊娠组相比无统计学差异,P>0.05。光镜下可见RSA模型组蜕膜细胞碎裂,数量较正常妊娠组减少;E003低剂量组和高剂量组蜕膜细胞数量均较模型组增多,排列较整齐。电镜下RSA模型组较正常妊娠组蜕膜细胞体积减小,细胞间隙增大,血管壁不完整,血管内皮细胞结构不完整,细胞核呈梭形;E003低剂量组与模型组比较,蜕膜细胞体积增大,细胞间隙增大,血管壁较完整,血管内皮细胞呈长梭形,细胞结构较完整,细胞间隙稍增宽;E003高剂量组蜕膜细胞组织及血管壁接近正常妊娠组。 结论　RSA模型小鼠存在母胎界面血管生成障碍,E003可修复RSA模型小鼠蜕膜组织中破坏的细胞结构,改善血管生成和细胞器形态,对RSA模型小鼠具有一定的治疗作用。     

股深动脉第1穿动脉穿支皮瓣修复臀股部IV期压疮疗效

目的　探讨应用股深动脉第1穿动脉穿支皮瓣修复臀股部IV期压疮的可行性。 方法　2016年1月至2019年2月,本院手足创伤骨科收治9例臀股部IV期压疮患者,男3例,女6例,年龄26~68岁,平均46岁。截瘫原因：高处坠落伤4例,车祸伤3例,脑梗塞2例。清创后创面面积8 cm×5 cm~18 cm×9 cm。根据创面形状、大小及位置设计股深动脉第1穿动脉穿支皮瓣修复压疮创面,皮瓣面积为10 cm×7 cm~20 cm×10 cm。 结果　所有皮瓣成活,其中2例术后局部渗液较多,经积极保守换药治疗后,皮瓣恢复良好。9例获得6~24月随访,平均13月,皮瓣色泽良好,质地柔软,不影响日常生活,压疮未见复发。 结论　股深动脉第1穿动脉穿支皮瓣操作简便,血供可靠,可供组织量较多,是修复臀股部IV期压疮的较好选择。     

骨髓间充质干细胞联合3D生物打印技术治疗骨缺损的研究进展

骨缺损一直以来都是临床治疗中的难题,目前主要是行自体骨或人工骨移植治疗。但自体骨取骨的损伤和人工骨资源有限且价格昂贵使得骨移植手术在临床广泛应用受到限制。近年来国内外学者对骨髓间充质干细胞诱导分化成骨的研究愈加重视,对其分离提取和定向分化的研究取得了长足的进步。骨髓间充质干细胞可向成骨细胞、软骨细胞等分化且不存在排斥反应及伦理问题,其结合3D生物打印技术修复骨缺损具有精准化和可控性的优势,是一种极具潜力和应用前景的新型骨缺损修复技术。文章对骨髓间充质干细胞的生物学特性、成骨诱导及结合载体支架治疗骨缺损的研究进行阐述,为今后在骨缺损的临床治疗中提供理论依据。     

A practical approach to the clinico-pathological diagnosis of panniculitis

Panniculitides are a group of diseases characterized by an inflammatory process that originates primarily in the subcutaneous tissue. Histopathological classification of panniculitides in mostly septal or lobular types, according to the predominant localization of the infiltrate, is complemented with the eventual identification of vasculitis and the consideration of the vessel size. Additional steps involve the characterization of the inflammatory infiltrate and other findings, such as, the type of adipocyte necrosis or the presence of sclerosis, crystals and foreign bodies. Apart from this purely histopathological characteristics, clinico-pathological correlation is often required to encompass the clinical, histopathological and laboratory data in order obtain the correct diagnosis. We will review the classification of panniculitis, useful histopathological clues for their diagnosis and diagnostic algorithms that can be applied when sclerosis is present or the inflammatory infiltrate is mostly neutrophilic.     

A Case Report of Non-Hodgkin Low-grade B-cell Mucosa-associated Lymphoid Tissue Lymphoma Presenting as a Suspected Endodontic Lesion

Extranodal mucosa-associated lymphoid tissue lymphoma is a rare oral disease. This case report describes a 71-year-old woman who presented for endodontic evaluation and treatment for swelling on the right posterior palatal. The case details the evaluation and diagnostic processes and treatment course. The case report draws attention to the importance of performing a biopsy, having proper sampling, and the additional steps sometimes required to arrive at a definitive diagnosis. This case report is the first to document a definitive low-grade B-cell mucosa-associated lymphoid tissue lymphoma mimicking endodontic pathology. The case shows the importance of proper examination, clinical imaging, and pathologic testing to arrive at a definitive diagnosis. It highlights that collaboration with other medical and dental specialties is essential for appropriate diagnosis and treatment and describes the “buttonhole” diagnostic strategy.     

临时冠塑形对前牙种植美学的临床观察

目的 在前牙区通过利用临时冠对种植体周围软组织进行塑形,观察最终修复的美学效果及软组织的稳定性。方法 选取本院种植科21例上前牙需要种植病例,牙种植后即刻或延期行临时冠修复,对种植体周围软组织进行塑形,待软组织稳定后,行个性化转移杆取模,制作最终修复体,使用红色美学指数（PES）来评价种植体周围软组织的美学效果。结果 11例患者PES≥12,9例8≤PES≤11,获得较好的美学效果。1例患者前牙区种植体支持固定桥修复,由于牙槽骨水平吸收,牙龈退缩,后期通过牙龈瓷进行美学处理。21例患者最终修复后观察1年,通过PES再次评价,同样获得较好的美学效果。结论 前牙种植术后利用临时冠对软组织进行塑形,能够将软组织调整到较好的美观外形,并且形态较稳定。此方法在前牙区种植修复是必要的,值得在临床中广泛推广。