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1.
5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-β) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p?相似文献   
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综述蛋黄卵磷脂的分子结构、提取方法、功能活性,以及在脂质体方面的最新研究现状。蛋黄卵磷脂结构主要是以甘油为骨架,通过酰基键与磷酸和脂肪酸连接而成的一种磷脂类两亲分子,根据碱基基团的不同,蛋黄卵磷脂包括了磷脂酰胆碱、磷脂酰乙醇胺、磷脂酰肌醇、磷脂酰丝氨酸、磷脂酸和磷脂酰甘油等6种。目前,提取蛋黄卵磷脂的方法主要有溶剂提取法和超临界萃取法;蛋黄卵磷脂具有抗氧化、抗菌、抗炎、神经保护和心脑血管保护等功能的生理活性;此外,还简单介绍了蛋黄卵磷脂脂质体的种类和应用现状。为蛋黄卵磷脂产品的开发提供良好的参考。  相似文献   
3.
刘鸿铖 《中国油脂》2020,45(12):49-55
探究注射级玉米卵磷脂(CLFI)对高脂膳食诱导的大鼠的降血脂作用。将60 只雄性SD大鼠随机分为6 组,即空白对照组、高脂模型组、阳性对照组(1.2 g/kg大豆卵磷脂)和CLFI高(2.4 g/kg)、中(1.2 g/kg)和低(0.6 g/kg)剂量组。除空白对照组给予基础饲料外,其余各组均给予高脂饲料,喂养2 周后开始对阳性对照组和CLFI各剂量组连续灌胃给药6 周,每天1 次。空白对照组和高脂模型组给予蒸馏水10 mL/kg。试验结束后考察大鼠血清血脂水平变化,检测大鼠体重、腹腔脂肪蓄积系数(AFC)、血清及肝脏中超氧化物歧化酶(SOD)活力和丙二醛(MDA)水平等指标,并观察肝脏的组织形态变化。结果表明:CLFI能有效抑制高脂膳食诱导大鼠的体重增长,降低血清中甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、MDA水平和动脉粥样硬化指数(AI)、血脂综合指数(LCI),并且降低AFC和肝脏中MDA水平;此外,高密度脂蛋白胆固醇(HDL-C)和SOD水平都有不同程度的提升,肝脏脂肪变性情况也得到改善。CLFI对高脂血症大鼠具有较好的降血脂和预防肝脏脂肪变性的作用,可为CLFI后续的开发和产业化应用提供一定的理论依据。  相似文献   
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Antimicrobial efficacy of methyl and propylparaben combination as potential preservatives for submicron emulsions, and the effect of oil and lecithin concentration on the microbial growth were investigated. Parabens were ineffective in standard or doubled concentrations as per pharmacopoeial criteria. Poor growth inhibition and multiplication of reference strains point to protective and growth properties of submicron emulsions. No correlation was observed between oil/lecithin ratio and efficacy of parabens; partitioning of the latter into the oily phase and lipophilic domains could be the reason for such effect. Further studies are necessary to establish a stable and safe composition of such formulations.  相似文献   
6.
以壳聚糖和卵磷脂为材料,采用乳化-交联法制备壳聚糖/卵磷脂复合微球,并用光学显微镜和红外光谱对微球进行表征;再以此微球作为载体固定木瓜蛋白酶,以固定率为指标,应用正交试验法优选固定化酶的制备工艺,并对固定化酶的半衰期、米氏常数(Km)、操作稳定性进行研究.结果表明,制备的壳聚糖/卵磷脂复合微球呈完整的圆球形或椭球形;固定化酶的优化制备工艺为:m(壳聚糖)=250 mg,m(壳聚糖):m(卵磷脂)=1:2,V(戊二醛水溶液)=300 μL,m(木瓜蛋白酶)=20 mg,此时制备的固定化酶的固定率达61.94%,半衰期为86.27 h,米氏常数为6.37 mg/mL,固定化酶有很好的操作稳定性.  相似文献   
7.
Nanoencapsulation of thiamine dilauryl sulfate (TDS), a vitamin B1 derivative, was proved to effectively inhibit the spore germination of Fusarium oxysporum f. sp. raphani (F. oxysporum), as well as mycelial growth. The average diameter of nanoparticles was measured as 136 nm by being encapsulated with an edible encapsulant, lecithin, whose encapsulation efficiency was about 55% in containing 200 ppm of TDS concentration: the 100 ppm TDS nanoparticle solution showed a mycelial growth inhibition rate of 59%. These results were about similar or even better than the cases of treating 100 ppm of dazomet, a positive antifungal control (64%). Moreover, kinetic analysis of inhibiting spore germination were estimated as 6.6% reduction of spore germination rates after 24 h treatment, which were 3.3% similar to the case of treating 100 ppm of a positive control (dazomet) for the same treatment time. It was also found that TDS itself could work as an antifungal agent by inhibiting both mycelial growth and spore germination, even though its efficacy was lower than those of nanoparticles. Nanoparticles especially played a more efficient role in limiting the spore germination, due to their easy penetration into hard cell membranes and long resident time on the surface of the spore shell walls. In this work, it was first demonstrated that the nanoparticle of TDS not a harmful chemical can control the growth of F. oxysporum by using a lower dosage than commercial herbicides, as well as the inhibiting mechanism of the TDS. However, field trials of the TDS nanoparticles encapsulated with lecithin should be further studied to be effectively used for field applications.  相似文献   
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ABSTRACT:  The formation of biocompatible nanoparticles via the self-assembly of chitosan (CHI) and modified lecithin (ML) was studied. Stable nanoparticles in the size range of 123 to 350 nm were formed at over a wide molar mixing ratios of CHI/ML solutions (amino group/phosphate group) (NH3+/PO3) and total polyelectrolyte (PE) concentrations (0.1 to 1 wt%) except at intermediate molar ratios when the surface charge was close to neutrality. Zeta-potentials of the nanoparticles were found to be independent of the total PE concentrations. Nanoparticles exhibited excellent stability at over an extended pH (pHs 3 to 6) and ionic strength range (≤ 500 mM NaCl concentration). The particle size and zeta-potential of the nanoparticles increased with the molecular weight of CHI. Transmission electron microscopy suggested that nanoparticles were generally spherical in shape with CHI constituting the exterior of its surface at high molar mixing ratios. Dextran-fluorescein isothiocyanate, bovine serum albumin, and Coomassie brilliant blue as models of nonionic, positively and negatively charged compounds were encapsulated within the nanoparticles at between 8.7% and 62.7% efficiency. The ability of the nanoparticle suspensions to be converted to lyophilized powder or concentrated suspension was also demonstrated.  相似文献   
10.
本文比较研究了鱿鱼卵磷脂和蛋黄磷脂对老年痴呆小鼠学习记忆能力的影响。雄性BALB/c小鼠分为正常对照、模型、鱿鱼卵磷组(SL)和蛋黄磷脂组(EL),喂养1周后,腹腔注射东莨菪碱造模并进行行为学测试。测定脑皮层、白质、海马中乙酰胆碱酯酶(Tch E)、超氧化物歧化酶(SOD)、单胺氧化酶(MAO)活力和脑内丙二醛(MDA)含量。结果显示,SL组水迷宫潜伏期显著降低,而穿越平台次数和目标象限停留时间显著提高,行为学改善效果优于EL组。SL能显著降低脑内各组织Tch E活力、MDA水平和白质中MAO活力,显著提高脑皮层、海马和白质中SOD活力,且作用效果优于EL。综上,鱿鱼卵磷脂通过影响中枢胆碱能神经系统和脑内抗氧化系统,改善了东莨菪碱所致痴呆小鼠学习记忆能力。  相似文献   
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