人胎盘来源Ⅳ型胶原蛋白的提取与纯化

目的从人胎盘中分离纯化Ⅳ型胶原蛋白,为制备其抗体提供抗原。方法选择人胎盘为提取原料,用胃蛋白酶消化、氯化钠盐析、凝胶化、超速离心、离子交换层析等方法,提取纯化Ⅳ型胶原蛋白。采用SDS-PAGE对提取的Ⅳ型胶原蛋白进行鉴定。结果胃蛋白酶消化法,使获得胶原蛋白的胶原链部分断裂,凝胶化方法可预先分离出组织中的Ⅰ、Ⅱ、Ⅲ型胶原蛋白,保留了Ⅳ、Ⅴ胶原蛋白,DEAE-Sephrose层析图表明,层析柱吸附的蛋白经洗脱得一主峰,经SDS-PAGE证实提取的Ⅳ型胶原蛋白的分子量80Kd和40Kd两条带。结论从人胎盘中提取的Ⅳ型胶原蛋白纯度高,符合Ⅳ型胶原的特征。提取材料广泛、实验条件简便,结果可靠。     

3种不同方式提取鳕鱼鱼鳔胶原蛋白与胶原蛋白肽的基本特性研究

目的 研究三种不同提取方式所制备的大西洋鳕鱼（Gadus macrocephalus）鱼鳔胶原蛋白的基本特性。方法 采用低温酸溶提取酸溶性胶原蛋白(acid-soluble collagen, ASC),热水抽提明胶(gelatin, GEL),复合蛋白酶酶解制备鳕鱼鱼鳔肽(swim bladder peptides, SWP)对鳕鱼鱼鳔中胶原蛋白的特性进行研究。对提取的胶原蛋白进行感官评定、SDS-PAGE电泳分析、紫外光谱分析、傅里叶红外光谱分析、氨基酸组成分析与扫描电镜分析。结果 ASC、GEL与SWP三种胶原蛋白的提取率分别为42.15%、72.20%与89.11%,且羟脯氨酸的含量为8.73%、8.97%与7.94%;SDS-PAGE图谱显示ASC至少由两条α链与一条β链组成,GEL中存在少量的α链与β链,SWP种α链与β链被降解。紫外光谱结果显示三种蛋白在230 nm波长处均有最大吸收;扫描电镜结果显示ASC与GEL具有一定的交联结构,SWP中无交联结构存在。结论 三种不同提取方式制备的胶原蛋白具有不同的特性,为鳕鱼鱼鳔胶原蛋白的开发与应用拓宽了领域。     

鱿鱼皮胶原蛋白医用止血材料的研究

目的 从鱿鱼皮中提取胶原蛋白并研究经化学和物理方法改性的鱿鱼皮胶原海绵的止血效果。方法 从新鲜鱿鱼皮中提取得到酸溶性胶原蛋白 (ASC)和酶溶性胶原蛋白 (PSC),冷冻干燥制备胶原海绵,分别采用EDC交联、干热交联 (DHT)、EDC/DHT结合交联这3种方法对其进行改性处理。采用兔耳创伤止血和肝脏止血试验来评价改性后胶原海绵的止血性能。结果 鱿鱼皮胶原蛋白ASC和PSC为典型的I型胶原蛋白。动物止血实验结果表明ASC-E、PSC-E、ASC-E/D和PSC-E/D等4种改性鱿鱼皮胶原海绵组均能对创面起到一定止血作用,其中尤以PSC-E组的止血效果最好,优于市售明胶海绵。 结论ASC-E、PSC-E、ASC-E/D和PSC-E/D等4种改性鱿鱼皮胶原海绵组均能有效的缩短出血时间,减少出血量,达到快速止血的效果,其中PSC-E止血效果最佳。     

巴沙鱼皮胶原蛋白的提取、组成及变性温度研究

目的 从巴沙鱼皮中提取胶原蛋白并分析其结构类型及氨基酸组成,同时研究物理、化学交联法对其变性温度的影响。 方法 采用酸提法和酶提法提取巴沙鱼皮中的胶原蛋白,并用SDS-PAGE凝胶电泳、FTIR和HPLC分析胶原蛋白的结构类型和氨基酸组成。通过测定粘度值研究物理、化学交联法对其变性温度的影响。 结果 酸提法提取胶原蛋白的提取率为58.2%,酶提法的提取率为22.0%;巴沙鱼皮鱼胶原蛋白为I型胶原蛋白;经120 ℃热交联后,巴沙鱼皮胶原蛋白的变性温度从34.2 ℃下降至28.0 ℃,经四甲基乙二胺(EDC)交联后,其变性温度上升至35.8℃。 结论 巴沙鱼皮富含I型胶原蛋白,酸提法比酶提法提取效率高,采用化学交联法可提高其变性温度,因而巴沙鱼皮可作为胶原蛋白的重要来源,可用于制备多种生物医用材料,具广泛的应用前景。     

罗非鱼皮明胶的抗贫血活性研究

目的从罗非鱼皮中提取了明胶,并以驴皮中提取的阿胶为阳性对照,在对比研究两者理化性质的基础上,研究了两者对缺铁性贫血的改善效果。方法采用饲喂低铁饲料辅助尾静脉放血的方法制备大鼠缺铁性贫血模型,灌胃不同剂量的阿胶和罗非鱼皮明胶。结果罗非鱼明胶和阿胶的紫外最大吸收峰都在232nm左右;2种明胶的氨基酸组成相似,均符合胶原蛋白(明胶)的氨基酸组成特点;罗非鱼皮明胶中的K、Mg含量显著高于阿胶,而阿胶中的Cu、Fe、Na、Cd、Cr含量明显高于罗非鱼皮明胶;罗非鱼皮明胶能够促进大鼠体重的恢复,提高血红蛋白(Hb)含量、红细胞数(RBC)等外周血指标,显著促进大鼠贫血症状的改善效果。结论罗非鱼皮明胶与阿胶...     

重组人红细胞生成素胶原蛋白双层微条的制备及含量测定

目的:制备重组人红细胞生成素(rhEPO)胶原蛋白双层微条并建立其含量测定方法。方法:以胶原蛋白为包裹材料,以硫酸软骨素钠为释放调节剂,采用凝胶加压成型的方法制备双层微条;采用反相高效液相色谱法测定双层微条中rhEPO的含量。结果:rhEPO检测浓度线性范围为0 .25～20μg/ml(r=0 9998) ,平均回收率为96 .2% ,日内、日间精密度分别为0. 9%、2 .6%(n=3)。结论:rhEPO胶原蛋白双层微条制备方法简单可行,含量测定方法准确、可靠。     

明胶海绵复合重组人成骨蛋白-1的骨修复材料免疫原性及肌肉刺激性实验研究

目的考察以明胶海绵为载体的重组人成骨蛋白-1(rhOP-1)骨修复材料的免疫原性及肌肉刺激性。方法以明胶海绵为载体制备rhOP-1骨修复材料,间接ELISA方法观察该骨修复材料植入小鼠体内的免疫原性反应,病理切片观察其对周围肌肉的影响及形态变化。结果ELISA结果表明,此法制备的以明胶海绵为载体的rhOP-1骨修复材料未引起小鼠的特异性抗体产生。植入部位肌肉虽出现炎细胞浸润现象,但炎症反应呈可逆性,未发现肌肉组织的坏死,且组织钙化现象明显。结论明胶海绵复合rhOP-1的骨修复材料在免疫原性和肌肉刺激性方面安全可靠。     

肝外胆管大出血10例术中处理体会

目的 介绍术中肝外胆管大出血处理的方法和体会。方法 12例术中大出血病例中2例用冷盐水纱布或去甲状腺素冷盐水纱条填塞胆总管止血；10例先用明胶海绵或胶原蛋白海绵等填塞胆管出血处，再用冷盐水加去甲。肾上腺素浸湿纱条填塞胆总管。结果 先用明胶海绵或胶原蛋白海绵等填塞胆管出血处，再用冷盐水加去甲。肾上腺素浸湿纱条填塞胆总管止血取得满意效果。结论 明胶海绵及胶原蛋白海绵等对胆管-血管瘘能起到填塞止血作用。     

单因素及正交试验法在酸法制备明胶中的应用

<正> 在动物的皮、肌腱、骨和结缔组织等中存在大量的胶原蛋白;这些胶原蛋白经过一定条件的水解,可以转化为明胶。明胶继续水解,可以得到短链的氨基酸多肽。山东阿胶厂用驴皮为原料,经熬胶、水解等制得的阿胶浆是深受医学界和病人欢迎的补品。近年来,明胶已从单一的食用型扩展到纺织、生物化工、医学卫生、日用化工、照相工业等许多领域,而且正在发展中。一、酸法制胶工艺简介从动物骨和皮中制备明胶,除酸法外,还有碱法,盐碱法,酶法等。     

胶原蛋白的制备及用作生物医用材料的研究进展

对动物结缔组织中重要的结构蛋白质--胶原蛋白提取、纯化的研究进展及其作为生物医用材料的新应用进行了综述.     

明胶管修复周围神经缺损的实验研究

目的　了解明胶管 (gelatinconduit)在修复外周神经缺损中的作用。方法　用明胶制成长1.0cm、内径 1.0mm的导管 ,套接修复大鼠右侧坐骨神经缺损 6.0mm ,左侧从同样规格的硅胶管套接作对照 ,于术后 3月进行电生理学、免疫组织化学、辣根过氧化物酶 (HRP)示踪等检查。结果　明胶管内有较多的再生神经纤维。明胶管套接侧胫前肌肌湿重、有髓神经纤维直径方面优于硅酮管 (P <0 .0 5 ) ,明胶管变薄无异物反应及炎症反应、无粘连。辣根过氧化物酶示踪证实在相应的背根神经节找到阳性的神经元。结论　作为一种新材料 ,明胶管能有效桥接坐骨神经缺损     

植物空心胶囊的研究进展

目前我国药用空心胶囊中绝大数为动物明胶空心硬胶囊。由于明胶的原料来源复杂、质量难控,这决定其存在诸多难以克服的性能及安全方面的缺陷。全球动物疫情频繁爆发、胶囊铬超标事件,使明胶空心胶囊面对前所未有的信任危机。因此,寻求质量更为可控的胶囊显得很有必要性,笔者综述了植物空心胶囊研究进展以期提供有益参考。     

The concentration of the cross-linking agent as a tool for the control of release and swelling properties of gelatin microspheres.

The effect of the concentration of a cross-linking agent (gelatin hardener) on gelatin microspheres was evaluated. A concentration increase of the gelatin hardener (formaldehyde) produced a decrease of drug loading, swelling degree and drug release rate. The cross-linking agent concentration affected also the kinetics of water absorption and drug release. This paper suggests a decreasing significance of the diffusion-type mechanism of drug release as the concentration of the cross-linking agent increased.     

Assessment of Albizia zygia gum as a binding agent in tablet formulations

Albizia gum has been evaluated as a binding agent in tablet formulations in comparison with gelatin BP. Compressional properties were analyzed using density measurements and the compression equations of Heckel and Kawakita as assessment parameters, while the mechanical properties of the tablets were assessed using the crushing strength and friability of the tablets. Drug release properties of the tablets were assessed using disintegration time and dissolution time as assessment parameters. Formulations containing Albizia gum as a binding agent show a faster onset and higher amount of plastic deformation under compression pressure than those containing gelatin. The crushing strength, disintegration and dissolution times of the tablets increased with increased binder concentration while their friability decreased. Albizia gum produced tablets with better mechanical properties and longer disintegration and dissolution times than those containing gelatin BP. This suggests that Albizia gum could be useful as a binding agent especially when high mechanical strength and slower release rates are desired.     

Gelatin behaviour in dilute aqueous solution: designing a nanoparticulate formulation.

Although it has been claimed that nanoparticles can be produced from gelatin, a naturally occurring polypeptide, the commercial conversion of animal collagen to gelatin results in a heterogeneous product with a wide molecular-weight range. This is probably responsible for the widely observed variation in the experimental conditions required for nanoparticle formation. In this study, 0.2% w/v aqueous B225 gelatin solutions were incubated under various conditions of time, temperature, pH and ethanol concentration and characterized by both size-exclusion high-performance liquid chromatography (HPLC) and dynamic light scattering. Gelatin was shown to be denatured when the temperature was increased to 37 degrees C (approx.) and the rate of renaturation was optimized over the temperature range 7-20 degrees C at pH 5.0, equivalent to the isoelectric point (IEP). The molecular-weight profile remained unchanged at 37 degrees C (approx.) in the pH range 5-7. When the gelatin solutions were mixed with ethanol, higher-molecular-weight fractions (microgel, delta and zeta fractions, all with molecular weights > 700 kDa) precipitated at ethanol concentrations lower than those required to precipitate the lower molecular weight material ( < 700 kDa), with maximum precipitation occurring close to the isoelectric point (pH 5.0). The molecular weight profile of gelatin in solution is evidently critically affected in a time-dependent manner by both pH and temperature. These two factors influence the noncovalent interactions responsible for the molecular structure of gelatin. The molecular weight profiles, in turn, affect the phase behaviour of gelatin in hydroalcoholic solutions. Systematically investigating the effect of time, temperature, pH and ethanol concentration on the molecular-weight-distribution profile of a gelatin solution enabled a robust method to be developed for the preparation of colloidal dispersions of non-aggregated gelatin nanoparticles 220-250 nm in diameter. This contrasts with the multiparticulate aggregates produced by earlier literature methods.     

Myo-inositol soft gel capsules may prevent the risk of coffee-induced neural tube defects

Objective: Neural tube defects (NTDs) are classified as folate sensitive (about 70%) and folate resistant (about 30%); although folic acid is able to prevent the former, several data have shown that inositol may prevent the latter. It has recently been proposed that coffee intake might represent a risk factor for NTD, likely by interfering with the inositol signaling. In the present study, we tested the hypothesis that, beside affecting the inositol signaling pathway, coffee also interferes with inositol absorption. Research design and methods: In order to evaluate coffee possible negative effects on inositol gastrointestinal absorption, a single-dose bioavailability trial was conducted. Pharmacokinetics (PK) parameters of myo-inositol (MI) powder and MI soft gelatin capsules swallowed with water and with a single 'espresso' were compared. PK profiles were obtained by analysis of MI plasma concentration, and the respective MI bioavailability was compared. Results: Myo-inositol powder administration was negatively affected by coffee intake, thus suggesting an additional explanation to the interference between inositol deficiency and coffee consumption. On the contrary, the concomitant single 'espresso' consumption did not affect MI absorption following MI soft gelatin capsules administration. Furthermore, it was observed that MI soft gelatin capsule administration resulted in improved bioavailability compared to the MI powder form. Conclusions: Myo-inositol soft gelatin capsules should be considered for the preventive treatment of NTDs in folate-resistant subjects due to their higher bioavailability and to the capability to reduce espresso interference.     

Bioavailability of flufenamic acid in hard and soft gelatin capsules.

The biological availability of flufenamic acid after oral administration of the drug in both hard and soft gelatin capsules was studied in dogs and humans. The soft gelatin capsules produced consistently higher plasma concentration-time curves.     

胶原-明胶海绵作为金葡液载体修复骨缺损的实验研究

目的初步探讨胶原-明胶海绵作为金葡液的载体修复骨缺损的可行性,为探索一种治疗骨缺损的新方法提供实验依据。方法选用Wistar大鼠30只,随机分为3组,每组10只。手术造成双侧股骨髁标准缺损后,A组左侧植入胶原-明胶海绵-金葡液复合物,右侧植入胶原-明胶海绵,B组左侧植入胶原-明胶海绵-金葡液复合物,右侧作为空白对照。C组左侧作为空白对照,右侧植入胶原-明胶海绵。于术后4周和6周行大体观察,X线拍片,组织学检查,灰重与湿重的测定。结果植入胶原-明胶海绵-金葡液侧具有高效的骨诱导活性,其成骨量也显著高于单纯植入胶原-明胶海绵侧和空白侧。结论胶原-明胶海绵作为金葡液的载体修复骨缺损,能减少金葡液局部注射的缺陷,提高其药物疗效,同时,胶原-明胶海绵能够阻挡周围软组织进入缺损区,为新骨生长提供空间。     

Enhancement of the dissolution rate and gastrointestinal absorption of pranlukast as a model poorly water-soluble drug by grinding with gelatin

The effect of grinding with gelatin on the dissolution behavior and gastrointestinal absorption of a poorly water-soluble drug was evaluated using the antiasthmatic agent, pranlukast, as a model poorly water-soluble drug. A ground pranlukast-gelatin mixture was prepared by grinding equal quantities of pranlukast and gelatin. In the dissolution testing, the dissolution rate of pranlukast in the suspension of the ground pranlukast-gelatin mixture under conditions of pH 3.0, 5.0 and 7.0 was markedly faster than that in the suspension of pranlukast. According to powder X-ray diffractometry (PXRD) and differential scanning calorimetry (DSC) analysis, the enhanced dissolution rate of pranlukast produced by grinding with gelatin was caused by changing the crystalline state of pranlukast into an amorphous state. In an animal experiment, the bioavailability of pranlukast following oral administration of the ground pranlukast-gelatin mixture to rats was threefold greater than that following administration of pranlukast. In the in vitro permeation experiment, the amount of permeated pranlukast through Caco-2 cell monolayers after application of the ground pranlukast-gelatin mixture was greater than that after application of pranlukast. These results suggest that the enhancement of the gastrointestinal absorption of pranlukast by grinding with gelatin is due to enhancement of the dissolution rate. Grinding a poorly water-soluble drug with gelatin is a useful method of enhancing its gastrointestinal absorption.     

Cytotoxicity of 5-fluorouracil entrapped in gelatin microspheres

Gelatin microspheres were prepared by water/oil emulsion polymerization and by cross-linking with glutaraldehyde. For the microsphere preparation procedure, two different gelatin (5 or 10% w/v) and three different glutaraldehyde (5, 0.5 or 0.1% v/v) concentrations were used. The influence of preparation compositions on microsphere recovery, particle size and morphology, swelling and degradation, 5-fluorouracil loading and release, and cytotoxicity were investigated. The concentrations of gelatin and glutaraldehyde influenced the size and surface properties of microspheres. The decrease in gelatin concentration and the increase in glutaraldehyde concentration resulted in the formation of smaller (140.82-71.47 microm for gelatin microspheres with a 5% gelatin content; 297.67-97.44 microm for gelatin microspheres with a 10% gelatin content) microspheres with smoother surface properties. Swelling values were decreased as the amount of glutaraldehyde was increased. In particular, for microspheres with a high glutaraldehyde content (5% v/v), only about 15% were degraded in 12 days, whereas for those with 0.5% (v/v) glutaraldehyde, almost 97% degradation occurred in the same period. The most rapid 5-fluorouracil release was observed from uncross-linked microspheres (about 88% in 4 h), whereas a particular slower release (about 36% in 4 h) profile was obtained for the highly cross-linked ones. Cytotoxicity tests of free and entrapped 5-fluorouracil were carried out with MCF-7 breast cancer cell line. Free 5-fluorouracil produced an immediate effect, whereas entrapped 5-fluorouracil showed a prolonged cytotoxic effect.