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1.
本文以苦荞总黄酮与大豆磷脂的复合率为评价指标,采用单因素考察对苦荞提取物与大豆磷脂形成复合物的制备工艺技术条件进行系统研究,并测定复合物在正辛醇和不同pH水溶液中的表观油水分配系数。结果表明:筛选出的最佳工艺条件为,以无水乙醇为反应溶剂,提取物的浓度为1 mg/mL,提取物与磷脂的质量比为1∶2,反应温度为40℃,反应时间24 h。与原提取物比较,磷脂复合物中总黄酮的表观油水分配系数有了显著的提高。按照该制备工艺制备的复合物复合率达到80%以上,同时结果表明磷脂复合物明显改善了苦荞总黄酮的脂溶性。  相似文献   

2.
溶剂挥发法制备制备青藤碱磷脂复合物。对制备的磷脂复合物进行X射线衍射(XRD)和核磁共振(NMR)分析。采用改进Franz扩散池进行离体SD大鼠皮渗透实验,并考察其体外透皮特性。XRD结果显示青藤碱以无定型状态存在于磷脂复合物中。NMR图谱显示青藤碱与磷脂酰胆碱发生氢键或分子间作用力。SD大鼠透皮实验显示青藤碱,磷脂复合物的渗透速率、增渗倍数及12 h内的累积渗透量均大于青藤碱原料药。因此,磷脂复合物能明显提高青藤碱的经皮透过量。  相似文献   

3.
为制备青藤碱磷脂复合物纳米结构脂质载体,并进行体外和SD大鼠体内评价。实验采用溶剂挥发法制备青藤碱磷脂复合物,乳化超声法制备青藤碱磷脂复合物纳米结构脂质载体。考察其粒径分布、Zeta电位,包封率,载药量及体外释药等基本理化性质。SD大鼠分别灌胃给予青藤碱混悬液和青藤碱磷脂复合物纳米结构脂质载体,比较药动学行为及生物利用度。结果显示,青藤碱磷脂复合物纳米结构脂质载体的平均粒径为201.32±5.05 nm,Zeta电位为-22.2±1.5 mV,包封率为80.31±1.01%,载药量为4.42±0.28%,体外释药具有明显的缓释特征,体外释药模型符合Weibull释药模型,拟合方程为:LnLn(1/1-Mt/M∞)=0.576 6Lnt-1.478 1(r=0.988 8)。体内药动学研究结果表明,磷脂复合物纳米结构脂质载体改变了青藤碱的药动学行为,增强了体内吸收,延长了青藤碱在体内滞留时间,相对生物利用度提高到了1.75倍。因此,青藤碱磷脂复合物纳米结构脂质载体可显著促进青藤碱体内吸收,提高其口服生物利用度。  相似文献   

4.
采用溶剂挥发法制备高乌甲素磷脂复合物,薄膜超声法制备高乌甲素磷脂复合物固体脂质纳米粒,并考察基本理化性质。SD大鼠分别灌胃给予高乌甲素及其磷脂复合物固体脂质纳米粒,比较药动学特征及生物利用度。结果表明,高乌甲素磷脂复合物固体脂质纳米粒平均粒径为(224.37±1.93)nm,Zeta电位为(-6.14±0.09)m V,包封率为(85.08±1.84)%。体外释药符合Weibull模型。药动学结果显示,Tmax,Cmax,AUC0~t和AUC0~?均具有统计学意义(P0.05或P0.01),口服吸收生物利用度提高了2.58倍。因此,高乌甲素磷脂复合物固体脂质纳米粒可有效提高高乌甲素的口服吸收生物利用度。  相似文献   

5.
以茶多酚磷脂复合物为研究对象,以茶多酚磷脂复合物对大肠杆菌的抑菌圈直径作为抑菌效果指标,对茶多酚磷脂复合物的抑菌条件进行了研究。考察茶多酚磷脂复合物浓度、壳聚糖浓度、柠檬酸浓度对大肠杆菌抑菌圈值的影响。在单因素试验的基础上,采用3因素3水平的响应面分析法对茶多酚磷脂复合物对大肠杆菌的抑制条件进行了优化,依据回归分析确定最优提取条件。结果表明,最佳抑菌条件为:茶多酚磷脂复合物的浓度为3.22 g/L,壳聚糖浓度为31.06 g/L,柠檬酸浓度为2.45 g/L。在此抑菌条件下,茶多酚磷脂复合物对大肠杆菌的抑制圈值达到最大,为18.1 mm。  相似文献   

6.
目的:制备葛胺酮(G20)-大豆卵磷脂复合物,提高G20的口服生物利用度。方法:以复合率为评价指标,采用单因素设计和正交试验优化复合物的制备方案,采用X线衍射分析该复合物的物理性质;SD大鼠分别灌胃给予G20及其卵磷脂复合物,RP-HPLC测定G20血药浓度,用药代动力学软件Winnonlin 5.2计算药动学参数。结果:复合物制备最佳条件为G20与卵磷脂的投料摩尔比为1∶1.5、乙醇量40 mL、反应温度50℃、反应时间2h,复合率为100%。在G20-卵磷脂复合物的X线衍射图中,不存在任何G20特征结晶衍射峰。与G20相比,其G20-卵磷脂复合物的口服生物利用度提高了160%。结论:采用磷脂复合物技术可以显著提高G20的口服生物利用度。  相似文献   

7.
为了探讨受体介导的基因转移技术在治疗血小板减少症方面应用的可行性,将促血小板生成素(Thrombopoietin,TPO)基因克隆入质粒型EB病毒表达载体pDR2中,并与半乳糖化组蛋白结合,从而制备了一种为肝细胞表面特异的脱唾液酸糖蛋白受体识别并内吞的核酸-蛋白复合物。在经化疗药物卡铂诱发的血小板减少症的实验动物大鼠中,同时静脉注射该复合物,可将TPO基因特异地导入肝细胞并在其中得到表达。从而有效地阻止了血小板减少症的发生,提示了一种以非病毒感染方式对化疗后血小板减少症进行有效基因治疗的可能前景  相似文献   

8.
核糖体是抗生素的主要靶点,而获得足量高纯度的核糖体是进行结构和药物研究的基础。结核分枝杆菌壁厚且生长缓慢,制备足量高纯度的核糖体具有挑战性。本研究改进并优化了核糖体纯化制备方法,通过大量培养和安全处理致病菌,应用高效破碎厚壁革兰阳性菌的技术,结合传统的蔗糖密度离心分离和蛋白液相色谱纯化技术,经多步纯化和分离,获得了高纯度和较高产率的耻垢分枝杆菌与结核分枝杆菌的核糖体样品,为后续生化实验和结构生物学研究提供了保证。该分枝杆菌核糖体制备方法也可应用于其他革兰阳性致病菌复合物样品的直接提纯,以及复合物特异性的进一步研究,特别是利用晶体学与冷冻电镜结合的高精度复合物结构研究,有助于揭示细菌耐药性机制及用于新型抗生素的研发。  相似文献   

9.
磷脂酰丝氨酸具有改善记忆和认知能力、防治老年痴呆症、抑郁症及缓解精神头力等作用,目前在国外被用作营养补克剂广泛应用于保健食品中.着重从提取法和酶转化法2个方面综述了磷脂酰丝氨酸的制备方法,同时通过对国内外磷脂酰丝氨酸消费现状的调查,对其在食品、药品、保健品方面的应用前景进行了展望.  相似文献   

10.
心磷脂和线粒体内膜   总被引:6,自引:0,他引:6  
心磷脂是构成线粒体内膜的主要磷脂之一,约75~90%的心磷脂分布在线粒体内膜脂双层的基质面,是线粒体内膜的特征性磷脂。心磷脂使线粒体内膜具有良好的流动性,利于呼吸链各复合物在膜脂双层中的侧向扩散。呼吸链的复合物与心磷脂特异结合才能表现其活性。在一定的条件下,心磷脂亦能形成六角形(?)相,这种多形性特点对离子转运和电子传递有重要意义。  相似文献   

11.
The aim of this study was to compare the effectiveness of antioxidants including Achillea millefolium extract (AmE) (n0t1.5: 1.5, n0t3: 3 and n0t4.5: 4.5 mg/L) and AmE loaded in nano phytosome (n1t1.5: 1.5, n1t3: 3 and n1t4.5: 4.5 mg/L) in the freezing of Ross 308 rooster semen. Sperm motility (CASA), membrane integrity (HOS test), viability, total abnormality and enzymatic parameters (SOD, CAT and GPx) were assessed after thawing. AmE-loaded nano phytosome at a concentration of 3 mg/l resulted in significantly (P < 0.05) higher total motility (MOT) (73.78 ± 2.92) and at concentrations of 1.5 mg/L and 3 mg/L in progressive motility (PROG) (14.12 ± 0.38, 16.78 ± 0.38) in comparison with the control group (MOT: 58.48 ± 2.92; PROG: 9.08 ± 0.38). Sperm viability (Vi) was higher (P < 0.05) in n1t3 (74.62 ± 1.55) and membrane integrity (Mi) in n0t3 and n1t3 groups (65.91 ± 1.91, 63.73 ± 1.91, respectively) compared to the control groups (Vi: 66.85 ± 1.55; Mi: 53.18 ± 1.91). Moreover, the lowest percentage of MDA was measured in n1t3 group (1.31 ± 0.31). There was no significant difference for SOD and CAT values with the use of various extenders.In conclusion, we suggest that AmE loaded in nano phytosome at 3 mg/l dose can be added to basic extender for improving rooster sperm motility, viability and oxidative stress values during the freezing procedure.  相似文献   

12.
Oncomirs are microRNAs (miRNA) associated with carcinogenesis and malignant transformation. They have emerged as potential molecular targets for anti-cancer therapy. We hypothesize that grape seed procyanidin extract (GSE) exerts antineoplastic effects through modulations of oncomirs and their downstream targets. We found that GSE significantly down-regulated oncomirs miR-19a and -19b in a variety of lung neoplastic cells. GSE also increased mRNA and protein levels of insulin-like growth factor II receptor (IGF-2R) and phosphatase and tensin homolog (PTEN), both predicted targets of miR-19a and -19b. Furthermore, GSE significantly increased PTEN activity and decreased AKT phosphorylation in A549 cells. Transfection of miR-19a and -19b mimics reversed the up-regulations of IGF2R and PTEN gene expression and abrogated the GSE induced anti-proliferative response. Additionally, oral administration of leucoselect phytosome, comprised of standardized grape seed oligomeric procyanidins complexed with soy phospholipids, to athymic nude mice via gavage, significantly down-regulated miR-19a, -19b and the miR-17-92 cluster host gene (MIR17HG) expressions, increased IGF-2R, PTEN, decreased phosphorylated-AKT in A549 xenograft tumors, and markedly inhibited tumor growth. To confirm the absorption of orally administered GSE, plasma procyanidin B1 levels, between 60 and 90 min after gavage of leucoselect phytosome (400 mg/kg), were measured by LC/MS at week 2 and 8 of treatment; the estimated concentration that was associated with 50% growth inhibition (IC50) (1.3 μg/mL) in vitro was much higher than the IC50 (0.032–0.13 μg/ml) observed in vivo. Our findings reveal novel antineoplastic mechanisms by GSE and support the clinical translation of leucoselect phytosome as an anti-neoplastic and chemopreventive agent for lung cancer.  相似文献   

13.
Quercetin, the plant-derived phenolic compounds, plays a pivotal role in controlling hemostasis, by having potent antioxidant and free-radical scavenging properties. This flavonoid in combination with chemotherapeutic drugs improves the efficacy of these agents in induction of apoptosis in cancer cells. This study investigated the role of nano-quercetin (phytosome) in doxorubicin-induced apoptosis. Nanoparticles were characterized for particle size, zeta potential, scanning electron microscopy (SEM) and differential scanning calorimetric assessments. Anti-proliferative effect of formulations was evaluated by MTT assay. mRNA expression levels of target genes were measured by real time RT-PCR. The mean size of nanoparticles was 85 ± 2 nm with nearly narrow size distribution which was confirmed by SEM analysis. Our results showed that co-treatment of MCF-7 breast cancer cells with nano-quercetin and doxorubicin increased the percentage of apoptosis from 40.11 ± 7.72–58 ± 7.13 (p < 0.05). Furthermore, mRNA expression levels for downstream genes including NQO1 and MRP1 showed a marked decrease (p < 0.05). Taken together, our results suggest that phytosome technology can elevate the efficacy of chemotherapeutics by increasing the permeability of tumor cells to chemical agents. Our findings introduce a novel phytosome-dependent strategy to improve delivery of doxorubicin to the breast cancerous tissues.  相似文献   

14.
戴国  卢光琇 《激光生物学报》2011,20(3):404-408,359
卵泡液是在卵泡形成过程中生成的,作为卵母细胞生长和分化的培养基,直接或间接影响卵母细胞的生育力和发育潜能,其成分非常复杂。本研究通过调整,优化2-DE技术条件,建立了相对稳定的卵泡液蛋白质2-DE技术,获得了卵泡液蛋白质组表达图谱,并用PDQuest软件进行了图像分析,用MALDI-TOF MS鉴定了9个蛋白点,其中有四种为新鉴定的在卵泡液中表达的蛋白质。结果表明,该体系稳定性、重复性好,为进一步开展卵泡液蛋白质组学的相关研究奠定了基础。  相似文献   

15.
As with many forms of flexible working, Annualized Hours (AH) systems offer potential benefits to both the employer and the employee. However, the flexibility requirements of employers and employees often conflict. Therefore, when a large food manufacturing organization decided to redesign its AH system, it employed an independent consultancy to act as neutral third party. The consultancy provided technical expertise and assistance in developing an AH system that optimised productivity and was acceptable to the workforce. Data are presented, obtained from focus groups conducted throughout the organization, describing some of the potential difficulties of implementing an AH system. Drawing upon these data, a number of new AH systems were proposed and modelled using specialist software tools. The design process is described, together with the advantages and difficulties associated with use of the software tools. It is concluded that the key elements in the process of designing AH systems are centred around issues of trust and communication; the involvement of a broad range of interested parties, through a process of carefully managed group facilitation; and the need for adequate technical support in the development and evaluation of AH systems.  相似文献   

16.
基于信息管理的一种虚拟森林景观构建及应用探讨   总被引:20,自引:0,他引:20  
在分析不同尺度的森林可视化建模内容和技术特点的基础上,提出了一个基于信息管理的虚拟森林景观构造原理和技术体系.把过程建模技术与树木形态结构描述结合,提出了一种交互式、参数化的树木动态建模方法,给出了相应的绘制方法和几何体简化算法以实现加速实时绘制,并以福建省漳浦县为例,建立了典型树种的几何模型库.利用森林调查和遥感动态空间数据,借助地理信息系统ArcObiect组件、图形环境OpenGL和Visual C++语言,开发了虚拟森林管理原型系统,实现森林二维/三维交互漫游、查询分析、森林生长仿真模拟,其真实感与模拟精度满足实际森林资源管理需求.最后给出了系统的典型用户界面以及在考虑竞争条件下马尾松自然生长模拟和人工间伐前后的虚拟景观对比的应用例子.  相似文献   

17.
Technical external quality assessment (TEQA) in Wales is based on NHSCSP publication 19, which sets out policy and procedures for the scheme. The purpose of EQA is to sustain and improve the quality of patient care by promoting a high standard of performance. Following the introduction of liquid base cytology (LBC) technical limitations, particularly in assessing counterstaining, have been noted. LBC provides the means to address these limitations - As part of a development plan for TEQA in Wales, a control sample procedure was introduced to the scheme. A pooled control sample was composed, containing residual material from six 'matched' negative samples, re-suspended in collection fluid. Aliquots of this sample were distributed for processing and staining, to the 13 laboratories registered with the scheme. The slides produced were assessed at a scheduled TEQA assessment in accordance with the standard criteria. Initial overall scoring for these control samples produced acceptable levels of staining for 12 of the laboratories - one laboratory produced a marginal score. Repeat distributions have shown maintained or improved results. This method provides a prospective quality assessment tool, which counters the emphasis on slide selection and eliminates potential selection bias, whilst introducing consistency and improving comparability across participant laboratories. The method may also prove helpful in identifying technical inconsistencies such as equipment or handling errors that may occur during sample processing prior to or during staining. The control process, which is now used routinely in the Welsh TEQA scheme; is considered complimentary to, and not a replacement for, the selection process established in NHSCSP #19. However, we feel that this development could be considered as a new initiative in the National TEQA scheme. The control process is applicable to all LBC systems in current use.  相似文献   

18.
Liang C  Wang J 《Biologicals》2011,39(5):312-316
In order to ensure most Chinese patients, particularly in the population with relatively low incomes, have access to safe, low cost, effective and quality-assured medicines, a number of "stand-alone" biological products, which have good quality, safety and efficacy have been marketed in China. Many countries and regions' regulatory agencies are actively engaging in the development of bio-similar guidance and documents, which is being coordinated by WHO. As a major developing country of new drug development, China is now working hard to promote the process of new similar biotherapeutic products (SBPs) approval and also actively involved in developing and updating technical documents.  相似文献   

19.
低能离子束生物工程的发展趋势   总被引:7,自引:0,他引:7  
简述了低能离子束生物技术在6个主要方面的研究成果。随着离子束生物技术不断发展,迫切需要建立一个更加完善的物理学平台,形成一个更加完整的研究体系,借助于其它学科的新技术或新工艺形成一个相互补充的技术集成体系,更应该将离子束生物技术的实用性和普遍性的范围不断地拓宽。明确提出了低能离子束生物工程的技术思路,即立足于低能离子束这一物理学技术平台,瞄准2个发展方向,促进3个有效转变,分清4个研究层次,注重5大生物学特性。  相似文献   

20.
Mass production of entomopathogenic nematodes for plant protection   总被引:2,自引:0,他引:2  
Entomopathogenic nematodes of the genera Heterorhabditis and Steinernema are commercially used to control pest insects. They are symbiotically associated with bacteria of the genera Photorhabdus and Xenorhabdus, respectively, which are the major food source for the nematodes. The biology of the nematode-bacterium complex is described, a historical review of the development of in vitro cultivation techniques is given and the current use in agriculture is summarised. Cultures of the complex are pre-incubated with the symbiotic bacteria before the nematodes are inoculated. Whereas the inoculum preparation and preservation of bacterial stocks follow standard rules, nematodes need special treatment. Media development is mainly directed towards cost reduction, as the bacteria are able to metabolise a variety of protein sources to provide optimal conditions for nematode reproduction. The process technology is described, discussing the influence of bioreactor design and process parameters required to obtain high nematode yields. As two organisms are grown in one vessel and one of them is a multicellular organism, the population dynamics and symbiotic interactions need to be understood in order to improve process management. Major problems can originate from the delayed or slow development of the nematode inoculum and from phase variants of the symbiotic bacteria that have negative effects on nematode development and reproduction. Recent scientific progress has helped to understand the biological and technical parameters that influence the process, thus enabling transfer to an industrial scale. As a consequence, costs for nematode-based products could be significantly reduced.  相似文献   

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