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1.
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。  相似文献   

2.
目的:制备F1,V,F1-V3种鼠疫耶尔森菌亚单位疫苗鼻腔免疫微球,研究其体外释放性质、抗原活性等性质。方法:采用复乳溶剂挥发法制备鼠疫疫苗微球,以激光粒度测定仪测定微球的平均粒径,以BCA法及微量BCA法测定微球的疫苗含量及疫苗从微球的释放,以ELISA法考察从微球中释放出的鼠疫疫苗的活性。结果:鼠疫耶尔森菌亚单位疫苗微球粒径均匀,F1,V,F1-V疫苗微球平均粒径分别为4.2,4.6和5.9μm,包裹率分别为68.2%,61.3%和51.0%,载药量分别为9.7%,8.7%和6.2%,微球中包裹的疫苗与原溶液相比活性降低不明显。结论:采用复乳溶剂挥发法,通过控制一定的因素,可以得到具有较高包封率的鼠疫耶尔森菌亚单位疫苗微球。  相似文献   

3.
常用的蛋白质保护剂对NGF-PLGA微球性质的影响   总被引:1,自引:0,他引:1  
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。  相似文献   

4.
GM-1 PLGA微球的制备工艺优化研究   总被引:4,自引:0,他引:4  
目的优化W/O/W型乳化溶剂挥发法制备GM-1PLGA微球的工艺。方法以载药量为检测指标,通过单因素分析和均匀设计法筛选影响微球制备工艺的10种因素,优化GM-1PLGA微球的制备工艺。结果在优化条件下制备的微球形态规则,粒径为(18.9±8.1)μm,载药量为4.91%,微球体外释药规律符合Higuchi方程:Q=0.153t1/2 0.03705,r=0.995。结论该制备工艺合理,为制备GM-1PLGA微球提供了理论依据。  相似文献   

5.
目的用生物可降解聚乳酸羟基乙酸共聚物(PLGA)制备载药微球包埋血管内皮生长因子(VEGF),并探索不同配比对释放行为的影响。方法采用不同分子量的PLGA制备不同粒径的载药微球,并经载药微球的合理配比改善其体外释放行为,达到优化工艺、降低成本的目的。结果载药微球粒径约为20μm、分子量10 kU:24 kU的配比为1:2组,粒径为20μm、分子量为24 kU和分子量为10 kU、粒径为6μm的载药微球配比为2:1组的体外释放突释较低,且在14 d内呈线性的零级释放趋势,体外释放行为得到改善。结论 VEGF长效缓释PLGA微球经优化配比后的持续释放能力较传统VEGF微球明显提高。  相似文献   

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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.  相似文献   

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目的制备载人骨形态发生蛋白-2(rhBMP-2)的甲基丙烯酸缩水甘油酯右旋糖酐(dex-GMA)凝胶微球并初步考察其体外溶胀、降解、载药与释药特征。方法以液体石蜡为油相,Span-80为乳化剂,采用乳化化学交联技术制备载rhBMP-2的凝胶微球(BMP-HMs)并通过正交设计法优化其制备工艺;观察BMP-HMs形态和粒径,测定其包封率与载药量;用微球的吸水能力表示微球的溶胀率(Rs),扫描电镜观察微球的体外降解,动态观察体外释药特征及其与微球溶胀、降解的关系。结果所制备的BMP-HMs形态规整,粒径40~50μm,分布均匀;rhBMP-2载药量(10.6±4.8)%,包封率(88.9±1.0)%,BMP-HMs冻干剂4℃以下存放6个月性能稳定,但在磷酸盐缓冲液(PBS)中20~40d内可以完全降解。微球Rs随反应促进剂四甲基乙二胺(TEMED)用量的增大而减小,0.3mlTEMED制备的BMP-HMs体外释药实验表明80%的rhBMP-2在前20d左右释放。结论BMP-HMs对rhBMP-2具有确定的缓释作用,并可以通过制备工艺的改变控制其释药。  相似文献   

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目的 制备载抑制性胆绿素还原酶A(BVR)多肽及全氟戊烷(PFP)的聚乳酸-羟基乙酸(PLGA)纳米微球(PPB NBs),评估其体外超声成像效果及与低强度聚焦超声(LIFU)联合使用抑制乳腺癌增殖及转移的能力。材料与方法 采用双乳法及碳二亚胺催化法制备PPB NBs,观察其形态大小、粒径、稳定性、表面电位及多肽包封率,并观察不同LIFU辐照时间的显影效果、载PFP的PLGA纳米微球(PP NBs)的细胞毒性,检测PPB NBs联合LIFU的抗增殖能力、抑制肿瘤细胞迁移和侵袭的能力。结果 PPB NBs乳液呈乳白色,纳米微球为粒径均一的球形,粒径(195.60±8.79)nm,7 d内粒径变化范围在24.50 nm内,多分散系数为0.064±0.030,表面电位为(-7.58±0.50)m V,多肽包封率为(82.94±1.10)%。二维超声及超声造影发现经LIFU辐照120 s为最佳显像时间,可证明PPB NBs成功包载PFP。PP NBs细胞毒性弱,细胞存活率在浓度最高(0.8mg/ml)时也超过75%。PPB NBs抗肿瘤能力呈浓度依赖性,多肽浓度为1 mg/ml时,细胞抑制率达...  相似文献   

9.
目的制备双氯芬酸钠微球,获得理想的释药行为。方法以微球的载药量、包封率及体外释药行为评价指标,采用单因素考察确立了最佳处方;结果最佳处方为:壳聚糖分子量为150kD,海藻酸钠:壳聚糖=3:1,药物:空白微球=1:4,吸附时间为12h,吸附温度为37℃,得到药物浓度为5.0mg·ml-1结论以该最佳处方制备的微球,具有均匀的粒径和理想的释药行为。  相似文献   

10.
顺铂壳聚糖微球制备工艺的研究   总被引:4,自引:0,他引:4  
选择壳聚糖为材料,用乳化化学交联技术制备顺铂壳聚糖微球,研究了影响微球制备的因素,在此基础上选择壳聚糖浓度(因素A)、水/油相体积比(因素B)、搅拌速度(因素C)、药物与鞯体材料用量比(因素D)、油相类型(因素E)、壳聚糖种类(因素F)及固化时间(因素G)七个因素,每个因素选择三水平,用正交实验设计安排实验,并以微球 载药量,药物包封率,粒子分布百分数为指标优化微球的制备工艺。  相似文献   

11.
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.  相似文献   

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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.  相似文献   

15.
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.  相似文献   

16.
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).  相似文献   

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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).  相似文献   

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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.  相似文献   

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