葡萄糖修饰的载胰岛素脂质体以包封率为指标的制备工艺研究

目的基于乙醇对脂质双分子层膜的去稳定作用制备得较高包封率的载胰岛素脂质体。方法本研究以空白大单室脂质体在乙醇存在的条件下对胰岛素进行主动载药。考察了脂质处方、乙醇浓度、孵育温度、孵育时间、PEG2000-succ-Chol用量、药脂比等对包封率的影响。结果乙醇存在条件下空白大单室脂质体对胰岛素进行主动载药而得粒径（180±70）nm的小多室脂质体,包封率为28%～32%。结论该方法制备所得的胰岛素脂质体比文献报道的包封率提高了近2倍,而且避免了使用有机溶剂,最大程度保护了胰岛素的生物活性。     

脂质体包封率测定方法研究进展

包封率是脂质体研究的重点,脂质体作为药物载体只有对药物的有效包载,才可能较好地发挥临床治疗作用.本文主要介绍脂质体包封率的各种测定方法并对其适用范围、优越性和局限性进行归纳总结,以期为载药脂质体的研发和应用提供参考.     

表阿霉素脂质体的制备与质量评价

目的:制备盐酸表阿霉素脂质体,建立HPLC含量测定方法并优选包封率测定方法.方法:采用薄膜分散-pH梯度法制备盐酸表阿霉素脂质体;采用HPLC测定药物含量;采用葡聚糖凝胶色谱、超滤及透析3种分离方法测定脂质体的包封率.结果:制备的表阿霉素脂质体粒径较小、分布较窄;3种方法测得盐酸表阿霉素脂质体的包封率分别为96.1%,98.4%,92.9%;结论:薄膜分散-pH梯度法适于制备盐酸表阿霉素脂质体,含量测定方法可靠.超滤法可以准确、快速地测定脂质体包封率.     

紫杉醇长循环肝靶向脂质体的制备

目的:制备紫杉醇长循环肝靶向脂质体(pac-GLs),并对制备的脂质体的性质进行评价.方法:用薄膜水化-高压均质法制备紫杉醇长循环肝靶向脂质体,纳米粒度测定仪测定其粒径,高效液相法测定其包封率.结果:制备的紫杉醇长循环肝靶向脂质体中的药物浓度为(1.00±0.10)mg/ml,包封率为(94±3)%.结论:本研究制备的紫杉醇长循环肝靶向脂质体包封率较高,质量可控,重复性好.     

多西他赛热敏脂质体的制备及含量和包封率的测定

目的制备多西他赛(DTX)热敏脂质体(docetaxel-loaded thermosensitive liposomes,DTL),建立其含量和包封率测定方法。方法采用薄膜分散法制备DTL并用高效液相色谱法(HPLC)测定脂质体中多西他赛的含量。采用高速离心法分离脂质体与游离药物并测定包封率。结果制备的DTL粒径均一,平均粒径为104 nm,相变温度为42.20℃。辅料和溶剂不干扰主药含量测定,线性范围为1.0～100.0μg/ml(r=1);多西他赛平均回收率为99.50%(RSD=0.65%)。药物在脂质体中的包封率大于98%。结论薄膜分散法可用于制备DTL。药物含量和包封率测定方法简便快速,准确可靠,专属性强。     

多西他赛热敏脂质体的制备及含量和包封率的测定

目的制备多西他赛（DTX）热敏脂质体（docetaxel-loaded thermosensitive liposomes,DTL）,建立其含量和包封率测定方法。方法采用薄膜分散法制备DTL并用高效液相色谱法（HPLC）测定脂质体中多西他赛的含量。采用高速离心法分离脂质体与游离药物并测定包封率。结果制备的DTL粒径均一,平均粒径为104 nm,相变温度为42.20℃。辅料和溶剂不干扰主药含量测定,线性范围为1.0～100.0μg/ml（r=1）;多西他赛平均回收率为99.50%（RSD=0.65%）。药物在脂质体中的包封率大于98%。结论薄膜分散法可用于制备DTL。药物含量和包封率测定方法简便快速,准确可靠,专属性强。     

马尼地平脂质体的制备及其质量研究

目的优选马尼地平脂质体的处方和制备工艺,并对其进行质量研究。方法采用乙醇注入法制备马尼地平脂质体,并对其形态学、粒径、包封率、初步稳定性等性质进行了研究。结果在透射电子显微镜下观察,制备的马尼地平脂质体为均匀的球状或近球状,平均粒径为233．9nm,包封率为89．6％,脂质体4℃放置稳定。结论选择乙醇注入法优化工艺制备马尼地平脂质体稳定可行,为进一步开发马尼地平新制剂提供了实验依据。     

高效液相色谱法测定奥扎格雷钠脂质体的包封率

 目的 建立高效液相色谱法(high performance liquid chromatography,HPLC)测定奥扎格雷钠脂质体包封率的检测技术。方法 采用HPLC,以C₁₈色谱柱分离,以0.05 mol/L磷酸二氢钾溶液(pH=7.0)-甲醇-乙腈(80∶15∶5)为流动相,检测波长为274 nm测定。结果 奥扎格雷在10～100 μg/ml浓度范围内线性关系良好,r=0.9997。日内、日间RSD均小于0.5%,方法回收率为(100.2±0.42)%,样品的平均包封率为(94.89±0.44)%。结论 该测定方法简单,准确度高,灵敏度好,适合奥扎格雷钠脂质体的包封率测定。     

盐酸表阿霉素-紫杉醇复方脂质体的制备

目的进行盐酸表阿霉素-紫杉醇复方脂质体的制备工艺研究并建立同时测定两药含量的高效液相色谱方法。方法采用薄膜分散-pH梯度法制备复方脂质体。Venusil MP C18色谱柱（250cm×4.6mm,5μm）;流动相：乙腈-甲醇-10mmol/L磷酸盐缓冲液（pH2.5）（36∶32∶32）;检测波长：227nm;流速：1.0ml/min。结果盐酸表阿霉素与紫杉醇出峰时间分别为4.2、14.8min;线性方程分别为Y=216300X-34525（r=0.9998,0.1~25μg/ml）,Y=161480X-84107（r=0.9998,0.3~75μg/ml）。盐酸表阿霉素和紫杉醇的回收率均在99%~101%范围内,日内和日间RSD均〈2%。制备的复方脂质体平均粒径162nm,盐酸表阿霉素与紫杉醇的含量分别为0.27、0.83mg/ml;包封率分别为98.6%、95.5%。结论本研究制备的复方脂质体粒径较小,包封率较高,建立的高效液相色谱法可以同时测定盐酸表阿霉素和紫杉醇的含量。     

Triple contrast technique for black blood imaging with double inversion preparation.

This work reports on the development of a pulse sequence to simultaneously acquire proton density, T(1), and T(2) weighted images in a single magnetization prepared fast spin echo acquisition. The technique is based upon the application of a magnetization preparation consisting of a global inversion followed by slice-selective 180 degrees and 90 degrees pulses to prepare the signal of specific slices. Slices are acquired in an interleaved manner with time delays appropriate for the desired image contrasts. Data acquisition is repeated for all combinations of slice interleaving covering the region of interest until images from all slice locations have been acquired with all desired image contrasts. The multiple image contrasts obtained with this technique should be useful in applications where discrimination between different types of tissue components is desired, such as in the analysis of plaque in cervical carotid artery disease.     

AxCaliber: a method for measuring axon diameter distribution from diffusion MRI.

The diameter of a myelinated nerve axon is directly proportional to its conduction velocity, so the axon diameter distribution helps determine the channel capacity of nervous transmission along fascicles in the central (CNS) and peripheral nervous systems (PNS). Previously, this histological information could only be obtained using invasive tissue biopsies. Here we propose a new NMR-based approach that employs a model of water diffusion within "restricted" cylindrical axons to estimate their diameter distribution within a nerve bundle. This approach can be combined with MRI to furnish an estimate of the axon diameter distribution within each voxel. This method is validated by comparing the diameter distributions measured using the NMR and histological techniques on sciatic and optic nerve tissue specimens. The axon diameter distribution measured in each voxel of porcine spinal cord using MRI and using histological methods were similar. Applications are expected in longitudinal studies designed to follow nerve growth in normal and abnormal development, as well as in diagnosing disorders and diseases affecting specific populations of axons in the CNS and PNS.     

痛舒颗粒的制备工艺

目的：研究痛舒颗粒的制备工艺。方法：采用正交试验的方法，以野黄芩苷含量、干膏收得率为指标综合评分，筛选出最佳提取工艺；采用单因素试验的方法对煎液浓缩的温度、制粒目数及颗粒干燥温度进行考察，筛选出成型工艺。结果：经3批中试研究，中试产品质量符合痛舒颗粒质量标准的各项规定，其成品收率达97．5％。结论：该生产工艺稳定、合理、可行，能够满足工业大生产的要求。     

Evaluation of a modified method for arthrography of the knee

A modified method for knee arthrography based on the technique introduced by Lindblom has been applied in 1 200 patients. The arthrographic reports on 132 patients submitted to arthrotomy are compared with the findings at surgery. The modified technique is easy to perform and offers a fairly reliable all-round method for diagnosis of both meniscus and crucial ligament lesions.     

兔肝癌模型的改良接种及其DSA影像分析

目的建立可供实验研究稳定的兔Vx2移植性肝癌模型,探讨不同植瘤方式的成功率,并分析该肿瘤的DSA影像特征。方法60只新西兰白兔随机分3组,每组20只。将Vx2瘤细胞(5×107个)经肝动脉或经肝包膜分别接种于2组兔的肝左叶,建立对照肝癌模型。第3组经肝包膜植入瘤组织块(约含106～108个瘤细胞)建立改良肝癌模型。观察:①不同组植瘤的成活率。②改良Vx2移植性肝癌的DSA影像特征。结果3组植瘤成活率分别为7/20、10/20、19/20,改良组植瘤成活率最高,差异有统计学意义(P<0.05)。DSA影像示该移植性肝癌具有丰富的血供。结论成功建立了兔Vx2移植性肝癌改良模型,瘤组织块种植方式成功率明显高于动脉途径和细胞液注射方式,为肝癌介入治疗的基础及临床研究提供了成熟的大型实验动物模型。     

Theoretical foundation for a simple method for simultaneous measurements of the unattached fraction and activity median diameter of attached radon progeny

Calculation of lung dose from established lung dosimetry models requires use of the unattached fraction of potential alpha energy concentration (PAEC) of radon progeny and the activity median diameter (AMD) of attached radon progeny, in addition to the total PAEC. In the present work, for indoor environments without the nucleation mode of aerosols, a method based on the wire screen penetration theory using two wire screens and a filter is proposed for simultaneous measurements of these two parameters. It is shown that the traditional wire screen method can overestimate or sometimes underestimate the unattached fraction, depending on the properties of the wire screen and the true unattached fraction. The present method eliminates such uncertainties.     

Gallium-67 activated charcoal: a new method for preparation of radioactive capsules for colonic transit study

Indium-111 is currently the radionuclide of choice for colonic transit study. However, it is expensive and not available in many hospitals. Technetium-99m has been proposed for colonic transit study but the short half-life has limited its use. Gallium-67 citrate is inexpensive and available in most countries. Most importantly, it has a suitable half-life for colonic transit study. Attempts have been made in some studies to use (67)Ga citrate to label activated charcoal, but the results have not been good because of poor stability. In this study, we successfully labelled activated charcoal()with (67)Ga citrate by adding alcohol and 5% glucose solution. To evaluate the in vitro stability, the (67)Ga-activated charcoal was incubated in a milieu mimicking the intestinal content, containing lipase, trypsin and glycochenodeoxycholate at different pH values (6.0, 7.0, 7.4 and 8.0) and for different durations (0 h, 24 h, 48 h, 72 h and 96 h). For the in vivo study, the (67)Ga-activated charcoal was loaded into a commercial empty enteric capsule. Colonic transit scintigraphy was performed in five volunteers, including three healthy people and two constipated patients, after intake of the radioactive capsule. Images were obtained at 2 h, 4 h, 6 h, 8 h, 24h, 48 h, 72 h etc. until no radioactivity was detected in the bowel. Our data show that the in vitro stability of (67)Ga-activated charcoal was good. The labelling efficiency still exceeded 91% at 96 h at pH values of 6.0, 7.0 and 7.4. In the group with a pH value of 8.0, the labelling efficiency gradually fell during the 4-day incubation but was still higher than 88% at the end of the fourth day. In the in vivo study, most capsules disintegrated in the caecum/colon region, and the (67)Ga-activated charcoal mixed very well with bowel content. In addition, the radioactive charcoal could be detected clearly on the 72-h image, which is very important for the evaluation of colonic transit time in patients with constipation. In conclusion, activated charcoal labelled with (67)Ga citrate is a potential radioactive marker for colonic transit study.     

Development of a rapid source preparation method for high-resolution α-particle spectrometry

In order to prepare sources of short-lived actinides for α-particle spectrometry, a coprecipitation method with Sm hydroxide was developed. The preparation procedure can be completed within 5 min with a high chemical yield of over 90%. It was found that the uniformity of the produced sources was sufficient to provide a high resolution of better than 20 keV. Under this method, we successfully measured the α-particle spectrum of short-lived Cf isotopes produced in the ²³⁸U(¹²C, xn) reaction.