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1.
Jianhua Zhang Mei Liu Hongjian Jin Liandong Deng Jinfeng Xing Anjie Dong 《AAPS PharmSciTech》2010,11(2):894-903
Lactate esters are widely used as food additives, perfume materials, medicine additives, and personal care products. The objective
of this work was to investigate the effect of a series of lactate esters as penetration enhancers on the in vitro skin permeation of four drugs with different physicochemical properties, including ibuprofen, salicylic acid, dexamethasone
and 5-fluorouracil. The saturated donor solutions of the evaluated drugs in propylene glycol were used in order to keep a
constant driving force with maximum thermodynamic activity. The permeability coefficient (K
p), skin concentration of drugs (SC), and lag time (T), as well as the enhancement ratios for K
p and SC were recorded. All results indicated that lactate esters can exert a significant influence on the transdermal delivery
of the model drugs and there is a structure-activity relationship between the tested lactate esters and their enhancement
effects. The results also suggested that the lactate esters with the chain length of fatty alcohol moieties of 10–12 are more
effective enhancers. Furthermore, the enhancement effect of lactate esters increases with a decrease of the drug lipophilicity,
which suggests that they may be more efficient at enhancing the penetration of hydrophilic drugs than lipophilic drugs. The
influence of the concentration of lactate esters was evaluated and the optimal concentration is in the range of 5∼10 wt.%.
In sum, lactate esters as a penetration enhancer for some drugs are of interest for transdermal administration when the safety
of penetration enhancers is a prime consideration. 相似文献
2.
探讨了研制的具有谷胱甘肽过氧化物酶活力的含硒抗体酶(GPX-abzyme)对于受损心肌线粒体的保护作用,利用牛的心肌线粒体为实验材料,通过线粒体的膨胀度、脂质过氧化物含量、CCO活力变化及电镜观察等几个方面证明GPX-abzyme能抵抗XO/HX系统产生的自由基的损伤作用,ESR研究也表明GPX-abzyme能明显降低XO/HX损伤系统中的自由基含量。 相似文献
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This paper presents results of Monte Carlo simulations of a full bilayer of 200 lipid chains and one gramicidin A dimer. Simulations are described for systems with lipid chains of 14, 16, and 18 carbons, respectively. Using accepted potential functions to calculate interactions between all non-hydrogen atoms a Monte Carlo configuration sampling is generated from which order parameter profiles are calculated and specific configurations are displayed. Results are compared with experimental data for lipid-gramicidin bilayers. 相似文献
5.
Production of MUC1 and MUC2 mucins by human tumor cell lines. 总被引:2,自引:0,他引:2
P L Devine G T Layton B A Clark G W Birrell B G Ward P X Xing I F McKenzie 《Biochemical and biophysical research communications》1991,178(2):593-599
A mucus secreting, clonal derivative (HT29-SB) of the human colonic adenocarcinoma cell line HT29, and the LS174T colon cancer cell line, secrete mucin into the culture medium as a viscoelastic gel. Mab BC2, which defines a peptide epitope present in the variable number of tandem repeats (VNTR) of the MUC1 core protein, reacted with this material after deglycosylation. Two high molecular weight bands were detected in TFMSA treated gel-formed mucin from HT29-SB and LS174T by western blotting (Mr 580 kDa and 420 kDa). A similar pattern of reactivity was seen with the culture supernatants from HT29-SB, the ovarian tumor cell line COLO-316, and the breast cancer cell line MCF-7. Mab CCP58 (anti-MUC2 VNTR) reacted with a 580 kDa band in gel-formed mucin produced by LS174T, but was not reactive with mucin produced by the other cell lines. The findings indicate that human colonic cell lines, in addition to breast and ovarian cell lines, may both express and secrete the MUC1 protein core, and that the LS174T cell line expresses and secretes both the MUC1 and MUC2 core proteins. 相似文献
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【目的】鉴定一株来源于中国南海海水样能够分泌多种胞外几丁质酶的类芽孢杆菌CAU904,并优化其产几丁质酶的发酵条件。【方法】采用形态学观察、16S r DNA序列比对及生理生化实验鉴定;通过碳源、氮源、温度、初始p H、表面活性剂种类以及发酵时间的单因素优化实验获得最佳发酵条件。【结果】菌株CAU904被鉴定为巴伦葛兹类芽孢杆菌(Paenibacillus barengoltzii),其最优发酵产酶条件为:0.5%胶体几丁质,0.2%酵母浸提物,0.1%吐温-80,培养基初始p H 7.0,45°C培养72 h。在最优发酵条件下,该菌株最大产酶水平达到8.2 U/m L,比优化前提高了5.4倍。几丁质酶的酶谱分析表明该菌株能够产生多达11种具有几丁质水解活性的同工酶,其中主要酶谱带对应分子量分别为54、47和38 k D。【结论】实验结果为巴伦葛兹类芽孢杆菌几丁质酶的分离纯化和酶的应用提供了基础。 相似文献
9.
Zehua Zou Ruixuan Liu Yiwen Wang Yufei Xing Zuowei Shi Kaifu Wang Darning Dong 《Acta biochimica et biophysica Sinica》2021,(3):294-303
The occurrence and progress of osteoporosis(OP)are partially caused by impaired osteoblast differentiation.Interleukin-I receptor antagonist(IL1RN)is an immune ... 相似文献
10.
对寄生蜂交配行为的了解将有助于发展对其行为调控的技术,提高寄生蜂对害虫控制的效能。为探讨椰心叶甲啮小蜂Tetrastichus brontispae Ferrière的复眼和触角在交配中的作用,用水溶性黑色素和液体石蜡分别涂抹该蜂复眼和触角后观察其交配行为,并利用扫描电镜(SEM)观察其复眼和触角的超微结构,分析雌、雄蜂触角感器的分布与数量差异。结果表明:椰心叶甲啮小蜂雄蜂的复眼在交配过程中起重要作用,雌蜂复眼作用不显著。在椰心叶甲啮小蜂求偶识别和接受过程中,雄蜂触角柄节部位起主要作用,其次是棒节部位,再次是鞭节的索亚节部位,而雌蜂触角鞭节索亚节部位起主要作用,然后是棒节部位,最后是柄节部位。扫描电镜观察表明椰心叶甲啮小蜂触角上共有8种感器,其中毛形感器和板形感器是主要感器,雌、雄蜂触角有明显的性二型现象,表现为触角大小不同及触角感器类型、大小、数量、分布不同。 相似文献