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1.
目的 制备一种应用于共载基因和化疗药的硫辛酸(LA)修饰的非内吞机制进入细胞的固有无序正常蛋白-细胞质定位的内化肽6(CL)的纳米复合物(LA-CL),并考察其对HEK293细胞的转染效率、胞摄取情况,以及体外释放规律。方法 以不同比例(2.5%、5%、10%、20%)半胱氨酸作为交联剂,合成四种不同交联度的LA-CLss (LA-CLss1, LA-CLss2,LA-CLss3, LA-CLss4),利用1H-NMR和凝胶色谱鉴定合成的LA-CLss。取增强绿色荧光蛋白质粒(plasmid Enhanced Green Fluorescent Protein, pEGFP) 和LA-CLss以不同氮磷比(N/P)(2.5, 5, 10, 20, 40, 80)自组装形成纳米复合物,粒度测定仪测定复合物的粒径和zeta电位,琼脂糖凝胶电泳测定载体LA-CLss对pEGFP的包裹能力以及保护作用。用超声乳化法制备载多西他赛的载药胶束,并用芘荧光探针法测定其临界胶束浓度。用LA-CLss/ pEGFP纳米复合物与人胚肾HEK293细胞共同培养,考察不同交联度复合物的细胞转染情况。结果 通过核磁结果确定LA-CLss合成成功;在N/P=40时,HEK293细胞对LA-CLss3/ pEGFP的转染效率高于其他四种 复合物(LA-CLss, LA-CLss1,LA-CLss2, LA-CLss4)。超声乳化法制备的载药胶束包封率为85.25 ± 0.04%,载药量为8.81 ± 0.02%。细胞摄取结果表明该载体可以有效地将基因递送进细胞内。体外释放实验结果表明该多肽胶束具有还原性条件敏感释药行为。结论 制备的LA-CLss纳米复合物有望成为一种高效的共载基因和化疗药的载体。  相似文献   

2.
目的:研究合成的以聚乙烯亚胺(PEI)为内核、聚赖氨酸(PLL)为外围的星形嵌段共聚物PEI-g-PLL的基因载体性能。方法:将PEI-g-PLL与pDNA复合形成PEI-g-PLL/pDNA复合物,并用琼脂糖凝胶电泳和zeta电位粒径分析仪表征;CCK-8法检测聚合物的HEK293细胞毒性;检测复合物在HEK293转染后Luciferase表达量以评价其转染效率。结果:PEI-g-PLL能复合pDNA形成尺寸约为200 nm的复合物,在HEK293中有较高的转染效率和较低的细胞毒性。结论:合成的PEI-g-PLL可用作潜在的基因载体。  相似文献   

3.
目的合成一种新型阳离子聚合物聚氨基酯(PBAE),并以此作为基因载体进行研究。方法通过迈克尔加成反应合成PBAE,以自主装法制备PBAE/pDNA纳米复合物,并考察PBAE/pDNA纳米复合物在HEK293细胞中的转染效率。结果当PBAE/pDNA的质量比为50∶1时,pDNA被完全包裹;在HEK293细胞转染实验中,当PBAE/pDNA质量比为200∶1时,其转染效率高于阳性对照组PEI/pDNA的转染效率(43.3%±3.7%vs 30.3%±2.1%,P<0.05)。结论带正电荷的PBAE能够通过静电作用浓缩包裹pDNA,在体外转染实验中具有较高的转染效率。  相似文献   

4.
壳聚糖修饰对细胞摄入和细胞毒性的影响   总被引:2,自引:1,他引:2  
目的研究精氨酸或十六烷基修饰壳聚糖对其细胞摄入和细胞毒性的影响及作用机制。方法用α-32P-dATP标记质粒DNA,分别与十六烷基化壳聚糖和精氨酸修饰的壳聚糖通过复凝聚方法形成壳聚糖DNA纳米复合物。采用血管平滑肌A10细胞进行摄入测试,并用β液闪计数仪检测结果。用MTT方法对壳聚糖DNA纳米复合物的细胞毒性进行评价。结果经32P标记的DNA与不同修饰的壳聚糖复合所形成的纳米复合物粒径约为55·9~174·9nm,zeta电位约为1·8~10·8mV。细胞摄入实验显示通过精氨酸或十六烷基修饰的壳聚糖与DNA形成的纳米复合物更易于进入细胞。其中十六烷基化壳聚糖DNA纳米复合物(HCNC)在N/P为1∶1时细胞摄入量最高,精氨酸修饰的壳聚糖DNA纳米复合物(ACNC)细胞摄入次之,与未经修饰的壳聚糖DNA纳米复合物(UCNC)相比,差异具有显著性(HCNC、ACNC比UCNC高1·3倍,P<0·05)。细胞毒性实验显示,修饰后的壳聚糖纳米复合物的毒性远远小于商品化的细胞转染试剂Lipofectamine2000。结论两种修饰对壳聚糖DNA纳米复合物的血管平滑肌细胞摄入有明显促进作用,其作用机制各不相同;同时其细胞毒性远小于商品化的细胞转染试剂Lipofectamine2000。  相似文献   

5.
目的 制备巯基烷基化壳聚糖(TACS)载基因纳米粒,并对其体外相关性质进行初步研究.方法 复凝聚法制备TACS/pDNA复合纳米粒子,并用透射电镜对其的形态和粒径进行观察和表征;凝胶阻滞分析观察其对基因的保护情况;以Lipofectamine 2000转染试剂作为阳性对照,检测其对人胚胎肾细胞(HEK293)的转染活性;四嚷氮唑盐(MTT)比色法测定其对细胞活性的影响.结果 TACS/pDNA复合纳米粒子形态不很均一,粒径在390 nm左右;凝胶阻滞分析证明了载体能有效地包裹和保护基因不受DNase Ⅰ酶的消化;体外基因转染实验证实了TACS纳米粒子能够有效地转染HEK293,其转染效率远高于壳聚糖纳米粒子,略低于脂质体;MTT测定其对细胞活力影响甚微,对细胞的毒性明显低于脂质体.结论 TACS有望成为一种有价值的新型基因载体.  相似文献   

6.
目的:选用聚-羟丙基-天冬氨酸-谷氨酸材料作为骨架偶联低分子量聚乙烯亚胺,以构建低毒、高效的新型非病毒性基因载体.方法:用聚-羟丙基-天冬氨酸-谷氨酸(PHPAG)为基本骨架,偶联低分子量的聚乙烯亚胺(PEI 1.8 kDa)形成聚-羟丙基-天冬氨酸-谷氨酸-聚乙烯亚胺(PHPAG-PEI 1.8 kDa)的载体材料.通过核磁共振氢谱(1H-NMR)、粒径测定、凝胶体积排除色谱法(GPC)等化学物理方法,凝胶电泳阻滞实验、MTT细胞毒性实验、细胞转染等生物学实验,对聚合物的结构及性能进行研究.结果:成功合成载体材料PHPAG-PEI 1.8 kDa.通过1H-NMR证实材料PHPAG-PEI 1.8 kDa在5或6个氨基酸上能偶合1个PEI 1.8 kDa.GPC结果表明PHPAG、PHPAG-PEI 1.8 kDa 2种材料的分子量约为1.2×104.粒径检测结果显示,PHPAG-PEI/pDNA复合物的平均粒径为200 nm左右.凝胶电泳阻滞实验表明,PHPAG-PEI/pDNA复合物在N/P为3.5∶1时可以完全阻滞DNA.细胞毒性实验表明,在COS-7和A293 2种不同的细胞中,载体材料显示出较低的毒性,与对照组PEI 1.8 kDa相近.在B16细胞、Hela细胞上的转染实验表明,PHPAG-PEI/pCAG-Luc3的复合物在N/P为25∶1时的转染效率最高,高于对照组PEI 25 kDa.结论:PHPAG-PEI聚合物载体材料是一种有潜在用途的非病毒基因药物载体.  相似文献   

7.
制备新型壳聚糖衍生物——尿刊酸修饰壳聚糖(UAC)/质粒DNA(pDNA)纳米复合物,采用凝胶电泳阻滞实验评价UAC包裹pDNA的能力;通过对各种影响因素(包括pH、渗透压、脱氧核糖核酸酶及肝素)的考察,对该纳米复合物的稳定性进行评价;利用激光粒度仪测定该纳米复合物的粒径和Zeta电位,透射电镜对其进行形态学观察。研究结果表明,高取代度(50.0%)的载体UAC在氮磷比(N/P)≥3时将pDNA完全包裹形成纳米复合物;N/P越高,该纳米复合物对碱性环境、高渗透压、DNaseⅠ、肝素的稳定性越好;低相对分子质量壳聚糖(20 kD)的UAC能够更有效地保护pDNA免受DNaseⅠ的降解,且形成的纳米复合物较容易被肝素解聚;N/P为30的纳米复合物的粒径为125.2 nm,Zeta电位为+37.9 mV,呈类球形结构。因此,高取代度、低相对分子质量壳聚糖的载体UAC与pDNA形成高N/P的纳米复合物能够具有良好的特性,适合进行细胞转染实验,有望成为一种新型载基因纳米复合物。  相似文献   

8.
目的 制备聚乙烯亚胺修饰纳米金基因载体并研究其理化性质的表征参数和体外转染效率.方法 通过化学还原法制备聚乙烯亚胺修饰的纳米金基因载体,用绿色荧光蛋白质粒(pAcGFP-N1)做报告基因,纳米基因载体可通过静电吸附的方式结合质粒DNA.用紫外分光光度计检测其吸收光谱,用透射电镜观察其形态特征,激光粒度分析仪测定其粒度分布、表面电位(Zeta电位),1%琼脂糖凝胶电泳检测该基因载体与质粒DNA的结合稳定性,CCK-8实验检测聚乙烯亚胺修饰纳米金基因载体及DNA-纳米金复合物对HEK293细胞的细胞毒性作用,通过荧光显微镜观察聚乙烯亚胺纳米基因载体介导pAcGFP-N1在体外培养的HEK293细胞中的表达,并分析其转染效率.结果 聚乙烯亚胺还原氯金酸可以得到带正电荷的纳米颗粒,呈单分散球形分布,其粒径为(12.3 ±3.3)nm.在pH =7.2时,Zeta电位为+(29.7±5.1)mV.1%琼脂糖凝胶电泳结果表明,当纳米金/质粒DNA≥0.5时,质粒DNA可完全结合到纳米金表面.体外转染实验表明,聚乙烯亚胺修饰纳米金基因载体能介导pAcGFP-N1转染HEK293细胞并在细胞中表达绿色荧光蛋白,其转染效率可达25%.结论 聚乙烯亚胺修饰纳米金是一种新型非病毒基因载体,具有转染效率高、对细胞毒性小等优势.  相似文献   

9.
关云  高彦晨  张兴  滕伟 《广东医学》2022,(10):1234-1239
目的 采用新型阳离子共聚物脂多糖胺(lipopolysaccharide-amine, LPSA)与质粒构建脂多糖胺/质粒复合物(LPSA/pDNA),探究其理化性能随氮磷比(N/P)变化规律。方法 构建含骨形态生成蛋白2(bone morphogenetic protein 2, BMP2)的非融合的真核表达质粒并鉴定。配置不同N/P的LPSA/pDNA复合物,凝胶阻滞实验探究LPSA与pDNA结合能力;动态光散射仪检测其粒径及zeta电位;透射电镜及原子力显微镜下观察LPSA/pDNA复合物形态;探究LPSA/pDNA复合物耐酶解能力随时间的变化规律。结果 经琼脂糖凝胶电泳及测序鉴定,真核表达载体BMP2编码序列片段与Genebank一致。随着N/P增加,LPSA/pDNA阻滞质粒DNA能力增加;当N/P>10时,LPSA可基本阻滞pDNA。LPSA/pDNA复合物的粒径随着N/P的增加先减小后增大,当N/P>3时,LPSA/pDNA粒径<150 nm;当N/P为12~25时,LPSA/pDNA粒径稳定于65 nm左右,LPSA/pDNA表面zeta电位呈正电性,...  相似文献   

10.
采用阳离子寡肽脂质材料赖氨酰化谷氨酸双十四醇酯(T2GL)制备阳离子脂质体(CL),与增强型绿色荧光蛋白质粒(pEGFP)静电结合形成复合物(CL/pDNA),CL/pDNA粒径和表面电位分别为(132.3±1.0)nm和+(31.35±2.99)mV。考察CL/pDNA对肝素及脱氧核糖核酸酶Ⅰ(DNase I)的稳定性,结果表明,CL/pDNA可被适宜浓度的肝素竞争性解组装释放pDNA,其对DNase I的稳定性明显优于市售制剂Lipofectamine 2000。研究CL与pDNA的比例(N/P)及质粒用量对转染效率的影响,结果显示当N/P为3,质粒用量4μg时,CL/pDNA的转染效率最佳。采用CL/pDNA对3种不同的细胞进行转染,发现CL/pDNA在人源非小细胞肺癌A549细胞中转染效果最好,与Lipofectamine 2000相比,转染效率相当但细胞毒性更低,因此为进一步研究其体内行为提供了良好的基础。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

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