以PGA为三维支架同种异体工程化软骨的构建

为探讨以聚羟基乙酸（PGA）为三维支架材料的同种异体软骨细胞构建组织工程化软骨的能力,采用胶原酶消化方法分离乳兔肋软骨获取种子细胞,收集体外培养传2-3代的软骨细胞,接种于经多聚赖氨酸处理的PGA支架材料上,将细胞-材料复合物种植在成兔皮下,一定时间取材,对获得的同种异体工程化软骨进行组织学评价。结果显示,软骨细胞体外培养1天后,在PGA支架上分布均匀;培养1周左右,PGA纤维间有呈蜘蛛网状基质产生。种植复合物4周取材可见PGA纤维未完全降解,软骨细胞不成熟,周边存在一定程度炎细胞浸润;8周取材,PGA纤维消失,软骨基本成熟,炎细胞浸润不明显。软骨基质含量丰富,分布与正常肋软骨组织学特征相似,提示以PGA为支架材料同种异体软骨细胞在有免疫力的动物体内可形成工程化软骨,无明显免疫排斥反应。     

应用组织工程化人工软骨修复羊关节软骨缺损的实验研究

目的 :探索以多孔磷酸三钙生物陶瓷材料为支架构建组织工程化软骨修复羊关节软骨缺损的可行性。方法 :实验分 3组。实验组 (n =12 ) :分离培养羊自体关节软骨细胞 ,采用微载体技术在旋转生物反应器内进行扩增 ,扩增后的软骨细胞接种到预制的 β_磷酸三钙 (β_TCP)多孔生物陶瓷材料上 ,细胞_材料复合体经体外孵育后 ,无菌条件下植入预制的羊前肢肱骨头关节面缺损处 ;单纯材料组 (n =12 ) :采用单纯 β_TCP材料修复羊关节软骨缺损 ;空白对照组 (n =4 ) :制备的羊关节软骨缺损区未做任何修复。术后 3和 6个月分别取材 ,进行缺损区组织学、组织化学和免疫组织化学分析。结果 :在实验组羊关节软骨缺损处表面肉眼可见透明软骨样组织形成。组织学检查发现 ,术后 3个月时材料降解明显 ,未降解吸收的材料孔洞内广泛分布着新生软骨组织 ,软骨细胞外基质丰富 ,Ⅱ型胶原染色阳性。至术后 6个月 ,支架材料几乎完全降解 ,缺损区被新生软骨组织所取代。在单纯材料组羊关节软骨缺损处术后 3个月时 ,可见从缺损区边缘有新生软骨组织向支架材料内长入 ,支架材料吸收明显。至术后 6个月 ,可见从缺损区边缘长入到支架材料内的新生软骨组织逐渐增多 ,但材料的中心部位未发现新生软骨形成。空白对照组羊关节软骨缺损区至术后 6     

小肠黏膜下层的制备及其在心肌组织工程中的应用

目的 制备小肠黏膜下层生物材料,并以其为支架材料体外构建工程化心肌组织.方法 将猪小肠黏膜下层以0.25%胰酶和0.5%SDS各处理24h,制备出脱细胞小肠黏膜下层.用材料试验机沿平行或垂直于管腔的方向进行单轴拉伸,检测其力学性能,同时检测其细胞毒性和组织相容性,然后将3日龄新生大鼠心肌细胞接种于小肠黏膜下层支架上,体外构建工程化心肌组织薄片,倒置显微镜下观察.经Masson组织化学染色、肌节型肌动蛋白免疫组化染色和透射电镜观察对获得的心肌薄片进行评价.结果 小肠黏膜下层的力学性能良好,已经完全脱去细胞,无细胞毒性,组织相容性良好;接种12h后,心肌细胞开始在小肠黏膜下层上搏动,2d后心肌细胞-支架复合物(工程化心肌组织薄片)开始自发搏动,可搏动14d.构建的工程化心肌组织薄片由多层心肌细胞构成并有大量胞外胶原.结论 成功制备出力学性能和生物相容性良好的小肠黏膜下层生物支架材料,并以其为支架成功构建出工程化心肌组织薄片.     

模拟微重力对改良纤维蛋白胶软骨细胞复合物培养的影响

目的研究模拟微重力条件对体外构建工程化软骨的影响.方法将兔软骨细胞种植到经抑肽酶和氨甲环酸改良的纤维蛋白胶支架材料上;设旋转培养组和静态对照组,体外培养3周,对复合物进行组织学观察和生化指标检测.结果采用改良支架的复合物经体外培养3周,软骨基本保持了原有塑形;相对于静态培养组,旋转培养组DNA、GAG的合成量增加,并在第3周出现显著性差异.结论经过改良的纤维蛋白胶支架能较长时间支持体外软骨组织的形成;旋转培养仪提供的模拟微重力环境可提高工程化软骨的质量,为实现关节软骨损伤的修复提供有效途径.     

应用胶原壳聚糖体外构建组织工程心脏瓣膜的初步研究

 目的探讨应用胶原壳聚糖支架体外构建组织工程心脏瓣膜的可行性.方法观察材料结构特点,并行兔皮下包埋实验,分别于4、6、8、12周观察材料的生物相容性和降解率.将犬主动脉壁间质细胞和内皮细胞种植于壳聚糖胶原支架上,观察其形态并测定细胞合成胶原和前列环素的功能.结果胶原壳聚糖膜呈网孔状结构,孔径(103±17)μm.皮下包埋实验显示材料生物相容性好,完全降解时间为12周.种植实验示细胞在材料表面生长良好,并具有合成前列环素(62.3±3.2 pg/mlvs10.7±2.1 pg/ml,P＜0.05)的功能.结论以胶原壳聚糖膜为支架体外构建组织工程心脏瓣叶,种植细胞不仅能在材料表面生长,还能合成细胞间质和血管活性物质,初步提示应用本组材料和方法构建组织工程心脏瓣叶是可行的.     

壳聚糖水凝胶局部注射对心梗的治疗作用研究

目的 观察心梗部位局部注射壳聚糖水凝胶的促血管生成及心肌保护作用.方法 将19只Wistar大鼠随机分为壳聚糖水凝胶注射组、单纯心肌梗死模型组、PBS注射组.结扎大鼠冠状动脉致心肌梗死30min后,心肌缺血处注射壳聚糖水凝胶.术后1、2、4周,分别处死动物进行组织学、免疫组织化学检查.结果 壳聚糖水凝胶注射1、2周后有明显存留,4周后已降解吸收,无明显残留,但注射后明显提高了心梗部位的心室壁厚度,梗死部位的血管密度明显增加,存活的心肌数量增多,结缔组织增生程度减轻.结论 心梗部位注射壳聚糖水凝胶可明显促进血管增生,有利于梗死部位心肌细胞的存活,适宜作为可注射性组织工程化心肌的支架材料.     

壳聚糖/聚磷酸钙复合支架的生物相容性研究

目的:评价比较不同配比壳聚糖/聚磷酸钙(Chitosan/Calcium polyphosphate,CS/CPP)复合支架的细胞相容性和组织相容性,探讨其应用于组织工程半月板支架材料的可行性。方法:采用扫描电镜检测半月板细胞在支架材料上的生长情况。采用MTT法检测不同配比CS/CPP支架材料浸提液对第3代半月板细胞的毒性,通过肌袋内植入试验评价支架材料的体内组织相容性。结果:扫描电镜下可见:不同比例CS/CPP复合支架材料呈三维多孔的结构。复合第3代半月板细胞体外培养7 d,细胞在支架材料上均匀分布,紧贴支架铺展伸长,生长良好。MTT法显示不同浓度支架浸提液与对照DF培养液吸光度值比较,差异无统计学意义(P>0.05),支架无细胞毒性。肌袋内植入试验评价:肌袋内植入实验显示动物术后生存良好,各植入部位均未见组织坏死、积液及化脓感染。术后1周植入体周围有较多中性粒细胞浸润;术后2~8周植入体周围中性粒细胞浸润逐渐减少,出现淋巴细胞浸润,淋巴细胞多于中性粒细胞,纤维囊壁厚薄不均;3个月后植入体周围未见炎症细胞浸润,主要为胶原纤维和成纤维细胞。随植入时间的延长,炎症细胞浸润逐渐减少,浸润范围逐渐缩小,包膜先逐渐变厚再变薄,植入材料内部逐渐有组织长入,并且逐渐降解。结论:CS/CPP具有良好的细胞相容性和组织相容性,有望成为半月板组织工程的支架材料。     

筛选适宜于构建工程化肝组织的凝胶材料支架

目的使用不同可注射性凝胶支架体外进行新生大鼠肝细胞立体培养,为后期体内植入筛选相容性较好的支架材料。方法使用胰酶冷消化法分离新生大鼠肝细胞。将肝细胞分别与纤维蛋白胶、壳聚糖凝胶、鼠尾胶原、透明质酸钠支架材料复合,形成工程化肝组织凝胶,接种于培养板中,并通过定期光镜来观察大鼠肝细胞,四唑盐(MTT)比色法评价细胞活性。溴甲酚绿法测上清白蛋白含量,脲酶比色法测定上清尿素含量。结果四组均可形成三维生长的工程化类肝样组织。培养第4天,生物蛋白胶及壳聚糖组的培养上清液中尿素含量达到高峰,分别为培养第1天的1.31倍和1.28倍,随后含量缓慢下降。培养第7天,新生大鼠肝细胞在纤维蛋白凝胶及壳聚糖凝胶中密集生长,同时MTT显示细胞活性及白蛋白分泌达到高峰,OD值分别为培养初期的1.11倍和1.17倍,上清白蛋白含量分别是初期的1.13倍和1.15倍。而在透明质酸钠及鼠尾胶原凝胶中则细胞生长缓慢,白蛋白及尿素含量持续下降。结论 4种可注射性支架中,壳聚糖和生物蛋白胶对于新生大鼠肝细胞生物相容性较好,透明质酸和鼠尾胶原较差,前两者更适合用于工程化肝组织的构建。     

定向结构组织工程软骨支架的构建

目的基于仿生学原理,构建类似软骨真实结构的定向结构组织工程软骨支架,以解决目前组织工程软骨修复过程中存在的支架亲水性相容性不够的缺陷以及新生软骨生理功能和机械性能不能长期维持等问题。方法选择软骨基质及壳聚糖共混溶液基于定向结晶及热致相分离工艺构建定向结构支架,研究支架孔径及力学性能生物相容性、细胞生长情况等。结果材料配比、模具底端温度等是影响着定向结构支架的孔径及力学性能的主要因素,定向结构支架轴向力学性能优于垂直轴向,细胞大量贴附支架表面,并沿着定向孔隙生长。结论采用上述方法构建的支架孔径可控,轴向抗压性能好,生物相容性,亲水性好,并有利于软骨细胞沿支架定向孔隙排布。     

不同细胞移植修复兔全层关节软骨缺损的比较研究

目的 :比较软骨细胞、骨髓基质细胞及成纤维细胞对全层关节软骨缺损的修复作用。材料和方法 :取幼兔的软骨细胞、骨髓基质细胞及成纤维细胞 ,共 3种有生成软骨潜力的细胞进行体外分离培养 ;以聚乳酸 (PLA)为载体 ,将培养的原代细胞植入PLA支架上 ,形成细胞 -PLA复合物。于 2 8只成年新西兰大白兔的股骨滑车关节面上造成直径 4 5mm、深 3 0mm的全层关节软骨缺损 ,将 3种细胞 -PLA复合物分别植入关节软骨缺损处。植入细胞 -PLA复合物为实验组 ,单纯植入PLA支架为对照组。术后 6周、12周观察缺损修复情况及新生组织类型。结果 :软骨细胞移植组为软骨样组织修复 ,分界明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨部分重建 ;细胞排列紊乱。骨髓基质细胞移植组为软骨样组织修复 ,分界不明显 ,甲苯胺兰及Ⅱ型胶原染色阳性 ;软骨下骨重建良好 ,软骨下潮线恢复 ;细胞排列趋于正常。成纤维细胞移植组为纤维组织修复 ,甲苯胺兰及Ⅱ型胶原染色阴性 ;软骨下潮线消失。对照组为纤维组织修复。结论 :软骨细胞、骨髓基质细胞移植修复软骨缺损明显优于成纤维细胞及对照组。骨髓基质细胞与软骨细胞移植组的修复结果无统计学差异 ,但骨髓基质细胞修复组织的细胞排列有序 ,软骨下骨重建良好 ,与周围组织融合密切 ,更接近正?     

Knee injury and Osteoarthritis Outcome Score (KOOS) - validation of a Swedish version

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.     

The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

Do Balance Board Training Programs Reduce the Risk of Ankle Sprains in Athletes?

Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).     

High Intensity Interval Training:New Insights

KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief，intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.，≥90%of VO2 peak).     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

Developmental validation of the PowerPlex(®) ESI 16 and PowerPlex(®) ESI 17 Systems: STR multiplexes for the new European standard

In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega^® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex^® ESI 16 (European Standard Investigator 16) and the PowerPlex^® ESI 17 Systems. The PowerPlex^® ESI 16 System combines the 11 loci compatible with the UK National DNA Database^®, contained within the AmpFlSTR^® SGM Plus^® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR^® SGM Plus^® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex^® ESI 17 System amplifies the same loci as the PowerPlex^® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR^® SGM Plus^® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex^® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.     

Bronchial stump fistula :treatment with covered retrievable hinged metallic stents-preliminary clinical experience

Objective To evaluate the preliminaily clinical efficacy and retrievability of a retrievable hinged covered metallic stent in the treatment of the bronchial stump fistula （BSF）. Methods Between April 2003 and March 2005, 8 patients with bronchial stump fistula after pneumonectomy or lobectomy were treated with two types （A and B） of retrievable hinged covered metallic stents. Type A stent was placed in 6 patients and type B in 2 under fluoroscopic guidance. The stent was removed with a retrieval set when BSF was healed or complications occurred. Results Stent placement in the bronchial tree was technically successful in all patients, without procedure-related complications. Immediate closure of the BSF was achieved in all patients after the procedure. Stents were removed from all patients but one. Removal of the stents was difficult in two patients due to tissue hyperplasia. Patients were followed up for 6 - 21 months. Placement of the stents remained stable in all patients except one due to severe cough. Permanent closure of BSF was achieved in 7 （87.5%） of 8 patients. Conclusion Use of a retrievable hinged covered expandable metallic stent is a simple, safe, and effective procedure for closure of the BSF. Retrieval of the stent seems to be feasible. （J Intervent Radiol, 2007, 16： 253-257）     

Prevalence and severity of hip and groin pain in sub‐elite male football: a cross‐sectional cohort study of 695 players

The purpose of this study was twofold: (a) to investigate the prevalence of hip and groin pain in sub‐elite male adult football in Denmark and (b) to explore the association between prevalence and duration of hip and groin pain in the previous season with the Copenhagen Hip and Groin Outcome Score (HAGOS) in the beginning of the new season. In total 695 respondents from 40 teams (Division 1–4) were included. Players completed in the beginning of the new season (July–Sept 2011) a self‐reported paper questionnaire on hip and/or groin pain during the previous season and HAGOS. In total 49% (95% CI: 45–52%) reported hip and/or groin pain during the previous season. Of these, 31% (95% CI: 26–36%) reported pain for >6 weeks. Players with the longest duration of pain during the previous season had the lowest HAGOS scores, when assessed at the beginning of the new season, P < 0.001. This study documents that half of sub‐elite male adult football players report pain in the hip and/or groin during a football season. The football players with the longest duration of pain in previous season displayed the lowest HAGOS scores in the beginning of the new season.