硬脑膜细胞体外培养模型的建立

目的：建立兔硬脑膜缺损的体外培养模型,观察不同细胞外基质对其愈合过程的影响,研究硬脑膜修复的机制,为以后检测硬脑膜移植物提供理论基础。方法：兔硬脑膜体外培养,再用免疫细胞化学方法和扫描电镜进行观察。结果：预先铺过胶原的培养板中培养8～10d后有细胞从硬脑膜缺损的边缘逸出、增殖,13～15d硬脑膜缺损愈合;而以多聚赖氨酸及层粘连蛋白铺底的培养板中没有看到细胞逸出的现象。硬脑膜细胞对波形蛋白抗体呈强阳性反应,对第Ⅶ因子抗体则为阴性反应;在电镜下可以看到新生胶原的生成。结论：成功建立一种硬脑膜缺损的体外培养模型;成纤维细胞从硬脑膜创缘的逸出、增殖是硬脑膜缺损愈合的重要机制。     

应用3D适形打印制备网状复合体对兔颅骨缺损的修复作用及安全性研究

目的:探讨采用3D适形打印技术制备的羟基磷灰石/聚乳酸网状复合体在兔颅骨缺损中的修复作用及安全性。方法:以24只新西兰兔为研究对象,以羟基磷灰石/聚乳酸为材料,采用3D适形打印技术制备网状复合体,于兔颅骨顶部制成两个颅骨全层缺损,分别为孔A(左)和孔B(右),孔A(阳性对照组)以自体颅骨为修复材料,孔B(实验组)以复合体为修复材料,观察缺损修复区域的形态学、影像学(X线及CT扫描)及组织学检查结果。结果:植入后24周时,形态学显示:阳性对照组可见致密的骨组织修复,与缺损边缘界限不清,实验组中支架孔隙内纤维组织由新生骨质取代,且新生骨成熟度较提高,材料表面有部分吸收。CT扫描观察显示:冠状面上,阳性对照组缺损修复区域与周围正常骨组织融合为一体,实验组修复材料与缺损边缘融合紧密,与周围正常骨组织结合良好,部分边缘结合不连贯。组织学观察显示:实验组材料部分降解,材料间隔可见新生骨小梁。研究中无实验动物死亡,皮肤切口处缝合良好,无皮下积液,无移植物脱出、红肿感染等情况出现。结论:以3D适形打印技术制备的羟基磷灰石/聚乳酸复合体对兔颅骨缺损有较好的修复作用,能促进缺损区域新骨的形成和生长,且安全性较高。     

胰岛素对糖尿病兔牙槽骨缺损修复的影响

目的：探讨胰岛素对糖尿病兔牙槽骨缺损修复治疗的效果,为糖尿病所致的牙周炎提供临床治疗的依据,方法：40只大耳白兔随机分为4组：A组制备健康兔的牙槽骨缺损;B组为胰岛素组,制备健康兔牙槽骨缺损后,用胰岛素治疗;C组为糖尿病组,制备糖尿病兔牙槽骨缺损;D组为糖尿病胰岛素治疗组,制备糖尿病兔牙槽骨缺损后,用胰岛素治疗。每组10只,缺损制备后4、8周各处死5只,对各组成骨情况进行组织学观察及测定。结果：组织学观察A、B、D组修复区可见大量新骨形成,以B组为显著;C组仅见少许成骨,多为纤维组织。新生骨面积比和成骨细胞数在4、8周时均为D组大于c组,B组大于A组,组间差异有统计学意义（P〈0．05）。证明应用胰岛素促进糖尿病兔缺损牙槽骨形成新骨的效果明显。结论：胰岛素能够促进糖尿病兔牙槽骨缺损的戍骨,为,临床上治疗糖尿病并发牙周炎提供一种新的手段。     

PIII 改性ePTFE 膜对细菌生存状态的影响研究

目的:探讨等离子注入技术(Plasma immersion ion implantation,PⅢ)对膨体聚四氟乙烯(ePTFE)膜改性后表面性能以及对细菌生存状态的影响.方法:采用氧等离子注入技术(PⅢ)对ePTFE膜表面处理,获得改性ePTFE膜,利用扫描电镜(SEM)观察改性ePTFE膜和未处理膜的表面形貌,体外培养变形链球菌,观察改性前后各组膜作体外细菌生存状态变化.结果:与未处理ePTFE膜相比,改性ePTFE膜表面形貌、亲水性发生改变.荧光染色后观察长脉冲组表面的细菌最少;短脉冲组膜表面粘附的细菌密集,形成生物膜;空白组可见少量死菌和活菌粘附于ePTFE膜上.结论:长脉冲PⅢ改性ePTFE膜后有良好的抗细菌粘附能力.     

新型多孔生物活性玻璃修复羊腔隙性骨缺损的实验研究

目的:评价新型多孔生物活性玻璃修复羊腔隙性骨缺损的能力.方法:12只成年绵羊L3-L5,共36个椎体均建立8mm× 15mm腔隙性骨缺损模型,实验组为Macro Porous Putty(MPS)和Injectable Putty(INJ),对照组为Nova Bone Putty(NBP).按照随机区组设计,随机分配每只羊的三个椎体缺损分别填充NBP、MPS、INJ材料.每种材料均填充12个椎体.术后6周、12周取材,通过术后一般状况、标本大体观察、X线平片以及组织病理学结果评价新型多孔生物活性玻璃的成骨作用.结果:①术后各组动物进食及粪便均正常,对外界刺激反应性良好.术后切口均一期愈合.②大体观察未发现缺损处有异常纤维组织包块及材料漏出.③术后6周和12周,MPS组和INJ组Lane-Sandhu X射线评分大于NBP组(P＜0.05).④组织学切片VG染色结果显示,术后6周和12周,MPS组和INJ组新生骨量多于NBP组(P＜0.05).MPS组和INJ组成骨性能相当(P＞0.05).术后12周和术后6周比较,NBP、MPS、INJ三种材料新生骨量均明显增多(P＜0.01).结论:新型多孔生物活性玻璃材料MPS和INJ具有可靠的骨缺损修复能力,比传统的NBP材料成骨能力更佳,具有良好的应用前景.     

表面改性双相陶瓷复合自体骨髓干细胞修复兔骨缺损的实验研究

目的:应用自体骨髓基质干细胞(Bone Marrow Stromal Cells,BMSCs)复合经低晶态羟基磷灰石(Low Crystalline Hydroxyap- atite,LcHA)涂层的双相陶瓷(Biphasic Calcium Phosphate,BCP)构建的组织工程化骨(LcBCP)修复兔桡骨节段性缺损。方法:体外分离培养、诱导扩增兔BMSCs,取第三代细胞复合LcBCP(实验组)后修复15只兔左侧桡骨15mm缺损;右侧桡骨缺损处植入复合BMSCs的BCP(对照组),于植入后4、8和12周处死动物,通过大体形态、组织学、影像学和扫描电镜检测骨缺损修复效果。结果:BMSCs-LcBCP复合物生长良好,随时间延长,X线显示实验组连接处骨痂形成,对照组连接处始终愈合稍差,12周大体观察实验组骨修复良好,髓腔再通;组织学显示板层骨形成,连接处骨性愈合,实验对照组连接处虽然也为骨性愈合,但尚有较多编织骨形成。结论:自体BMSCs复合LcBCP形成的组织工程化骨可修复兔桡骨节段性缺损,低晶态羟基磷灰石涂层能够增强双相陶瓷的早期成骨。     

改良Papineau植骨术与抗生素磷酸钙骨水泥局部应用治疗牵张成骨并发Ceirny Ⅲ型骨髓炎的比较研究

目的:探讨改良Papineau植骨术与抗生素磷酸钙骨水泥局部填塞治疗牵张成骨技术使用中并发Ceirny Ⅲ型骨髓炎的疗效。方法:回顾性分析自2013年1月到2015年4月采用改良Papineau植骨术与抗生素磷酸钙骨水泥局部填塞治疗牵张成骨技术并发Ceirny Ⅲ型骨髓炎17例。A组6例,采用清创后磷酸钙骨水泥5 mL混合0.5 g万古霉素粉剂清创后填塞治疗。B组11例,采用改良Papineau植骨术,即清创后,按5 mL体积松质骨混合0.5 g万古霉素粉剂,清创后植入缺损部位。两组病例术后均行封闭负压吸引(VAC)治疗7天。随访病人局部疼痛缓解情况,皮肤红肿表现、窦道愈合情况、骨缺损部位骨愈合情况以及术后复发情况来判定疗效并比较分析。结果:17例病人术后随访12~20个月。A组全部病例术后2~3周局部炎症消退,创口愈合,定期检测血白细胞计数(WBC)、血沉(ESR)和C反应蛋白(CRP)均下降至正常,2例再未出现感染征象,4例病人于术后3~10周再次出现渗液,局部皮肤发红,ESR、CRP进行性升高表现。再次给与清创,换药治疗后逐渐愈合,随访再无渗液出现。B组病人11例,创口2~3周内全部愈合,定期检测WBC、ESR和CRP均下降至正常。随访未见复发。结论:抗生素负荷磷酸钙骨水泥在牵张成骨技术治疗后并发Ceirny Ⅲ型骨髓炎时,虽有效果,但复发率较高,改良Papineau植骨术疗效更好。     

微弧氧化和碱处理技术在多孔钽修复兔颅骨缺损中的应用

目的观察微弧氧化和碱处理对多孔钽表面性状、生物相容性和成骨能力的影响。方法微弧氧化和碱处理多孔钽片后,扫描电镜观察表面微孔数量、表面钙磷沉积和接触角。植入钽片修复兔颅骨缺损模型,在4周和12周观察骨愈合情况。结果扫描电镜显示处理组表面有更多的微孔和钙磷沉积以及更小的接触角(P<0.05)。植入多孔钽片后,所有动物均生长良好,伤口愈合佳。CT观察多孔钽片和周围骨组织耦合良好;钙黄绿素标记检测显示12周时有新生骨长入多空钽材料内部;扫描电镜观察发现4周时多空钽材料内部有新生血管,12周时有骨小梁长入材料内部。结论微弧氧化和碱处理能改变多孔钽材料表面形状,处理后多孔钽片具有良好的生物相容性和成骨能力。     

人工骨表面覆盖口腔修复膜对颌骨囊性缺损人工骨植入术患者植入腔感染的预防作用

目的:探讨人工骨表面覆盖口腔修复膜对颌骨囊性缺损人工骨植入术患者植入腔感染的预防作用。方法:将我院2012年4月～2016年2月收治的78例颌骨囊性缺损患者按治疗时间分为对照组38例与观察组40例,均行开窗人工骨植入术,其中对照组采取常规抗感染,观察组采取人工骨表面覆盖口腔修复膜。比较两组的囊腔体积、面积缩减率、人工骨植入量、骨厚度及植入腔感染率。结果:两组的囊腔体积、面积缩减率及人工骨植入量比较差异无统计学意义(P0.05)。但观察组的骨厚度明显大于对照组(P0.05),植入腔感染率明显低于对照组(P0.05)。结论:在开窗人工骨植入术的基础上使用口腔修复膜不仅能引导骨组织再生,而且能够显著降低植入腔的感染率。     

生长激素-海藻酸钠-壳聚糖微胶囊促进骨折愈合的组织学研究

目的:观察生长激素-海藻酸钠-壳聚糖微胶囊促进兔挠骨骨折愈合的作用。方法:实验将新西兰兔80只,在制备新西兰兔右桡骨中段3mm骨缺损模型的基础上,随机分成四组:口服生长激素-海藻酸钠-壳聚糖微胶囊组、皮下注射生长激素组、口服空微胶囊组和生理盐水对照组。实验组口服生长激素-海藻酸钠-壳聚糖微胶囊和皮下注射生长激素,对照组口服空微胶囊。并于术后9、17、30、42d定期HE染色和地衣红染色观察各组的骨折愈合情况。结果:本实验HE染色结果表明,由于在骨缺损部位成纤维细胞产生的大量胶原纤维为基质,形成透明软骨及成骨细胞,骨小梁生长的基础,连接骨痂形成和骨髓腔贯通。而观察到生长激素微胶囊组各期提前生长及改建提前的形态。地衣红染色图像结果分析及直方图的分析表明:生长激素微胶囊组胶原纤维产生促进骨小梁提前形成,进而骨折处骨性骨痂的提前愈合和髓腔的提前贯通。结论:生长激素-海藻酸钠-壳聚糖微胶囊口服能促进骨折修复愈合。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.