牛血清白蛋白乳酸-羟乙酸共聚物微球的制备

目的 以牛血清白蛋白为模型蛋白,以乳酸-羟乙酸共聚物（PLGA）为包裹材料,探索粒径小于10μm的微球的制备方法并优化工艺。方法采用复乳溶剂挥发法制备蛋白质微球,以BCA法及微量BCA法测定微球的蛋白含量及蛋白从微球的释放。考察BSA浓度,内外相体积比,PLGA浓度,超声功率,匀浆转速,PVA浓度,PVA体积,PLGA分子量等因素对微球包封率、粒径、载药量及突释量的影响。结果通过控制不同的因素,可以得到较高的载药量及包封率、粒径在5μm左右的微球。结论采用复乳溶剂挥发法通过控制不同的因素,可得到粒径5μm左右不同载药量及突释量的具有较高包封率的微球。     

常用的蛋白质保护剂对NGF-PLGA微球性质的影响

目的研究常用的蛋白质保护剂对微球性质的影响特点。方法复乳化溶剂挥发法制备NGF-PLGA微球，分别添加葡萄糖，聚乙二醇，卵清蛋白作保护剂，观察微球的形态，载药量、包封率及体外释放特点，研究保护剂的作用特点。结果保护剂对微球的粒径、包封率和载药量影响不明显，粒径集中分布在10-40μm，载药量0．0007％-0．0011％，包封率7％～11％。保护剂主要影响微球的形态和体外释放。添加不同的保护剂，微球表面的光滑度和孔隙差别较大；体外释放的突释较小，存在明显的缓慢释放期，进入快速释放期的起始时间和释药速度受保护剂影响显著，一个月内的累积释放药量达到80％以上。结论保护剂的分子量可能是微球形态和释放不同的原因，添加分子量大的保护剂形成的微球的表面比添加分子量小的保护剂时致密光滑，体外的缓慢释放期长。     

紫杉醇长效缓释微球的制备与评价

目的：制备包含肉豆蔻酸异丙酯(IPM)的紫杉醇长效缓释微球，并对制备工艺及体内外缓释效果进行评价。方法：使用改良的单乳溶剂蒸发法制备紫杉醇长效缓释微球。通过分析粒径分布、突释、体外释放及体内的抑瘤效果等指标，对其进行评价。结果：所得微球平均粒径小于10μm，外观圆整，具有良好的体外释放曲线。含有30％IPM的微球体内抑瘤效果明显。结论：使用改良的单乳溶剂蒸发法制备的微球，可以达到缓释效果，体外释放4周的微球对小鼠体内的固体肿瘤有良好的抑制效果。     

载鼠疫亚单位疫苗多孔微球的制备及其免疫效果评价

目的制备载鼠疫F1抗原疫苗多孔微球,并评价其免疫效果。方法采用生物可降解高分子材料PLGA制备多孔微球,考察不同致孔剂对微球形态和孔隙率的影响,并将鼠疫F1抗原蛋白疫苗吸附到多孔微球上,分别于第0天和第21天肌肉注射免疫BALB/c小鼠,以其为实验组,分别以单独注射疫苗和单独注射多孔微球的小鼠为对照组。在第6、8、10周取血测定抗体滴度,并于第10周取血后皮下注射鼠疫杆菌攻毒（剂量：600×LD50）,攻毒后观察14d。结果 F1抗原多孔微球组抗体滴度明显高于对照组（P〈0.05）;攻毒后,F1抗原多孔微球组免疫的小鼠全部存活,且健康状况良好,而F1抗原对照组小鼠存活率为20%,多孔微球对照组小鼠全部死亡。结论多孔微球球形良好,孔隙率高,用作鼠疫亚单位疫苗载体可以明显提高其免疫效果。     

卡铂-乳酸/羟基乙酸共聚物微球的制备和体外性质

目的制备卡铂-乳酸/羟基乙酸共聚物(PLGA)微球,比较不同方法所得微球的形态、载药量和体外释药特点。方法采用相分离法和溶剂挥发法制备卡铂-PLGA微球,显微镜下测定微球的粒径和粒径分布,电子扫描显微镜观察微球表面形态。用电感耦合等离子体发射光谱法(ICP-AES)测定微球含药量,计算包封率,考察微球体外释药行为。结果两种方法所得微球球形较好,相分离法制得的卡铂-PLGA微球,平均粒径为22~31μm,含药量为42~61μg·mg-1、包封率21%~31%;体外释放试验中药物于24h完全溶出。溶剂挥发法所得微球平均粒径为38~54μm,含药量为7.2μg·mg-1、包封率约为20%;体外药物突释率约为39%,缓释期药物释放符合Higuchi模型,PLGA75/25、η=0.19和PLGA50/50、η=0.18的微球药物释放速度常数分别为2.40h-1/2和0.85h-1/2;体外14d累计释药分别达到71%和54%。结论相分离法制备卡铂-PLGA微球含药量高,但体外释药快,没有缓释作用;溶剂挥发法所得微球药物突释率较低,体外能控制药物缓慢释放。     

紫杉醇/海藻酸钠微囊/微球的缓释及抑瘤作用研究

目的：以海藻酸钠为主要材料制备紫杉醇的缓释微囊／微球，对其形态、粒径、体外释放以及抑瘤活性进行研究。方法：扫描电镜观察微球的形态和大小。HPLC法测定紫杉醇在释放介质中的浓度。MTT法测定体外抑瘤活性。结果：制备的紫杉醇／海藻酸钠微囊／微球的形态呈规则圆形，粒径相近，平均粒径256μm。冷冻干燥后呈不规则球形。颗粒长径约100μm，表面形成皱襞。微囊载药量为25％左右，而微球不足10％。微囊与微球均具有缓释作用，体外实验证明保持了抑瘤活性。结论：海藻酸钠-紫杉醇微囊／微球具有缓释作用，可以维持较长时间的有效药物浓度，达到更好的抑瘤效果。     

不同制备工艺对胶质细胞源性神经营养因子微球理化性质及生物活性的影响

目的 评价不同制备工艺对胶质细胞源性神经营养因子(glial cell line-derived neurotrophic factor,GDNF)缓释微球的影响及微球所包裹的GDNF生物学活性.方法 以聚乳酸-羟基乙酸共聚物(polylactide-co-glycolide,PLGA)为包裹材料,采用复乳法(W1/O/W2)制备GDNF-PLGA微球,通过两因素析因设计方差分析,研究PLGA中乳酸(LA)与羟基乙酸(GA)单体组成比例和复乳搅拌速度对GDNF微球的粒径、包封率、突释率和体外释放行为的影响,并用PC-12细胞检测微球所释放的GDNF生物学活性,确定最佳制备工艺.结果 PLGA的单体组成比例可影响微球的突释率(P＜0.05),对粒径和包封率的影响无统计学意义,随着GA比例的增加,微球中GDNF释放速度加快.复乳搅拌速度由1 000 r/min增加到3 000 r/min后,微球的粒径显著减小(P＜0.01),突释率显著增加(P＜0.01),体外释放更为快速.微球中的GDNF在37℃下活性有效期可达20 d左右,较单独存放的GDNF活性有效期延长10 d以上.结论 复乳法可制备具有较高包封率和适宜体外释放时间的GDNF缓释微球,且活性有效期延长.

Abstract：

Objective To evaluate the effect of different preparation processes on preparation of the glial cell line-derived neurotrophic factor(GDNF)loaded microspheres and observe the biological activity of GDNF.Methods With polylactide-co-glycolide(PLGA)as the coating material,the GDNF-loaded microspheres were prepared by using double emulsion(W1/O/W2).Two-factor factorial design variance analysis was done to analyze the effects of the composition proportion of lactic acid(LA)and glycolic acid(GA)in PLGA and the stirring speed of multiple emulsion on particle size,entrapment efficiency,burst release and in vitro release characteristics of the GDNF-loaded microspheres.PC-12 bioassay was employed to detect the biological activity of the released GDNF so as to determine the optimal preparation process.Results The composition proportion of PLGA could affect the microspheres'burst release(P ＜ 0.05),with no effect on particle size and entrapment efficiency.with the higher.With higher proportion of GA,the release speed of GDNF in the microspheres was increased.When the stirring speed of multiple emulsion was increased from 1 000 r/min to 3 000 r/min,the particle size of the microspheres was decrease significantly(P ＜ 0.01),the burst release was increased markedly(P ＜ 0.01)and the in vitro release rate was accelerated.The activity of GDNF in the microspheres could last for about 20 days at 37℃,which was 10 days longer than that of single GDNF.Conclusions Double emulsioncan prepare the GDNF-loaded microspheres with high entrapment efficiency and suitable in vitro release time.In the meantime,the microspheres can extend the validity of GDNF.     

重组人表皮细胞生长因子缓释微球治疗糖尿病大鼠溃疡

目的 制备重组人表皮细胞生长因子(rhEGF)缓释微球,并对其形貌、释药行为和在体外促进细胞增殖的能力进行评价;同时比较rhEGF缓释微球与rhEGF原液对糖尿病大鼠溃疡促愈作用的差异. 方法 (1)用改进的复乳法制备rhEGF缓释微球.透射电镜检测rhEGF微粒形貌表征,激光粒度仪/Zeta电位仪分析微球粒径分布,ELISA法测定rhEGF微球释药行为.(2)以小鼠成纤维细胞L929细胞系为对象,采用MTT法鉴定rhEGF缓释微球的生物学活性.(3)制备糖尿病大鼠溃疡模型,成模后采用随机数字表法将大鼠分为4组:rhEGF缓释微球组(A组)、rhEGF原液组(B组)、空白微球组(C组)、PBS溶媒对照组(D组),每天给药1次.分别于给药后3,7,14,21 d对溃疡创面照相计算创面愈合率.创缘皮肤取材,测定羟脯氨酸含量,免疫组化检测β1整合素和角蛋白-19并测量其阳性染色面积比. 结果 (1)rhEGF缓释微球平均粒径为193.5nm,粒径分布均匀,微球之间元粘连,分散性好.释药过程符合Higuchi释放动力学模型,释放时间长达24 h.(2)不同浓度rhEGF缓释微球均有促进小鼠成纤维细胞增殖的作用,其中以10μg/L浓度促小鼠成纤维细胞增殖的作用最强.(3)从治疗第7天开始,愈合率以A组最快,A组与其他三组比较,差异均有统计学意义(P<0.05).羟脯氨酸含量、β1整合素和角蛋白-19阳性染色面积比A组均高于B组. 结论 用改进的复乳法制备的rhEGF缓释微球,粒径大小分布均一,释放时间长达24 h.rhEGF缓释微球促进糖尿病大鼠溃疡创面愈合速度较rhEGF原液更快,溃疡创面愈合质量更高.     

溶剂挥发法制备水溶性药物的聚羟基酸微球

羟基酸或其内酯的聚合物是目前研究最多、应用最广泛的可生物降解的药用合成高分子材料 ,常用聚乳酸(ＰＬＡ)和乳酸羟基乙酸共聚物 (ＰＬＧＡ) ,由于具有无毒、生物相容性好、可生物降解等特点 ,以它们为基质的微球给药系统受到普遍重视并得到广泛的应用 ,其制备方法较多 ,以溶济挥发法最为常用[1～ 3 ] 。对于水溶性药物若用传统的Ｏ/Ｗ乳剂溶剂挥发成囊 ,一般将会导致药物迅速从有机相转移入水相 ,从而使微球载药量很少甚至根本不载药。现已有溶剂挥发法的改进方法 ,主要是利用Ｏ/Ｏ乳剂系统和复乳系统 ,综述如下。1　Ｏ/Ｏ型乳剂系统将聚…     

蛋白芯片筛选鼠疫耶尔森菌与巨噬细胞的蛋白相互作用

目的：利用蛋白芯片筛选鼠疫耶尔森菌的毒力因子，进一步揭示鼠疫菌与宿主之间相互作用的机制。方法：鼠疫菌毒力相关蛋白芯片筛选与小鼠巨噬细胞系774A．1可能有相互作用的蛋白质，免疫荧光试验验证筛选出的蛋白相互作用。结果：共筛选到17个可能与巨噬细胞有相互作用的鼠疫菌蛋白，并通过免疫荧光试验初步验证了其中8个蛋白芯片筛选试验中信号最强的蛋白与巨噬细胞的相互作用。结论：蛋白芯片技术可用于筛选病原菌与宿主之间的相互作用，有助于深入研究病原与宿主之间相互作用的机制。本研究筛选出的鼠疫菌蛋白与巨噬细胞的相互作用尚需深入研究和验证，以便最终确定这些蛋白在鼠疫菌致病机制中所发挥的作用。     

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.     

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.     

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).     

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.