水凝胶对PICC置管后机械性静脉炎的预防作用研究

目的 观察水凝胶对PICC置管后机械性静脉炎的预防作用.方法 将2010年8月～2011年8月我院普外科361例因癌症化疗需要行PICC穿刺置管患者随机分为两组,实验组182例和对照组179例,实验组置管后使用水凝胶加3M透明敷贴,对照组置管后使用3M透明敷贴,观察两组PICC置管后10d内机械性静脉炎的发生率、严重程度及其发生时间.结果 PICC置管后10 d内实验组7例发生静脉炎,平均发生于置管后(6.6±1.5)d,对照组18例发生静脉炎,平均发生于置管后(3.6±2.0)d,两组静脉炎发生率及发生时间比较差异有显著意义(P＜0.01);两组静脉炎发生的严重程度比较差异有显著意义(P＜0.05).结论 水凝胶对PICC置管后机械性静脉炎具有良好的预防作用.     

HPLC法测定双氯芬酸钠水凝胶中双氯芬酸的含量

目的:建立HPLC法,测定双氯芬酸钠水凝胶中双氯芬酸的含量,用于医院内制剂的质量标准研究。方法:采用高效液相色谱法,以Kromasil ODS(250 mm×4.6 mm,5μm)为分析色谱柱;流动相:甲醇-pH 2.5磷酸盐缓冲液(70∶30);流速:1 mL.min-1;检测波长:254 nm;柱温为室温。结果:双氯芬酸在0.05～0.80 mg.mL-1浓度范围内具有良好的线性关系。结论:该方法可准确、快速、简便地测定双氯芬酸钠水凝胶中双氯芬酸的含量。     

Neurotropic growth factors and glycosaminoglycan based matrices to induce dopaminergic tissue formation

Current cell replacement therapies in Parkinson's disease (PD) are limited by low survival of transplanted cell and lacking regeneration of neuronal circuitries. Therefore, bioartificial cell carriers and growth/differentiation factors are applied to improve the integration of transplants and maximize newly generated and/or residual dopaminergic function. In this work, biohybrid poly(ethylene glycol) (starPEG)-heparin hydrogels releasing fibroblast growth factor 2 (FGF-2) and glial-derived neurotrophic factor (GDNF) were used to trigger dopaminergic tissue formation by primary murine midbrain cells in vitro. Matrix-delivered FGF-2 enhanced cell viability while release of GDNF had a pro-neuronal/dopaminergic effect. Combined delivery of both factors from the glycosaminoglycan-based matrices resulted in a tremendous improvement in survival and maturation capacity of dopaminergic neurons as obvious from tyrosine hydroxylase expression and neurite outgrowth. The reported data demonstrate that glycosaminoglycan-based hydrogels can facilitate the administration of neurotrophic factors and are therefore instrumental in potential future treatments of PD.     

Preparation,characterization, and antibacterial activity of plaunotol and plaunoi extracts complexed with hydroxypropyl-β-cyclodextrin

Croton stellatopilosus (Plaunoi) leaves accumulate several diterpenes and possess various pharmacological activities. The present study aimed to prepare, characterize and assess the antibacterial activity of inclusion complexes prepared by mixing plaunotol (PL) or plaunoi extract (PE) with cyclodextrins (CD), including α-CD, β-CD, γ-CD, and hydroxypropyl-β-cyclodextrin (HP-β-CD). The inclusion complexes were characterized using SEM, XRD, DSC, and FT-IR and evaluated for aqueous solubility and thermal stability. The PL and PE lyophilized complexes with HP-β-CD were further evaluated for their antibacterial activity against acne-causing bacteria. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of PL, PE, and the inclusion complexes evaluated using the agar dilution method revealed that the MIC and MBC values of the inclusion complexes were lower than those of PL or PE alone. Interestingly, the complexes had a synergistic activity with clindamycin after testing with checkerboard assay. The hydrogel containing the inclusion complex and clindamycin were assessed for antibacterial activity using the agar well diffusion method. The results indicated that the hydrogels showed significant inhibition of bacterial growth. In conclusion, the prepared solid dispersion of PL or PE with HP-β-CD could enhance antibacterial activity by increasing the drug solubility. The hydrogels containing PL or PE complex and clindamycin could be considered as a candidate for the treatment of acne vulgaris.     

聚乙烯醇水凝胶及其复合物的研究与在人工软骨替代材料上的应用

聚乙烯醇水凝胶是一种具有良好生物相容性和力学性能的高弹性材料。本文介绍了聚乙烯醇水凝胶的成型方法，复合改性技术的研究进展，着重对聚乙烯醇水凝胶作为替代材料在关节软骨损伤修复中的研究现状和存在问题进行了综述，并概述了其应用前景和发展方向。     

Hydrogel nanoparticles in drug delivery

Hydrogel nanoparticles have gained considerable attention in recent years as one of the most promising nanoparticulate drug delivery systems owing to their unique potentials via combining the characteristics of a hydrogel system (e.g., hydrophilicity and extremely high water content) with a nanoparticle (e.g., very small size). Several polymeric hydrogel nanoparticulate systems have been prepared and characterized in recent years, based on both natural and synthetic polymers, each with its own advantages and drawbacks. Among the natural polymers, chitosan and alginate have been studied extensively for preparation of hydrogel nanoparticles and from synthetic group, hydrogel nanoparticles based on poly (vinyl alcohol), poly (ethylene oxide), poly (ethyleneimine), poly (vinyl pyrrolidone), and poly-N-isopropylacrylamide have been reported with different characteristics and features with respect to drug delivery. Regardless of the type of polymer used, the release mechanism of the loaded agent from hydrogel nanoparticles is complex, while resulting from three main vectors, i.e., drug diffusion, hydrogel matrix swelling, and chemical reactivity of the drug/matrix. Several crosslinking methods have been used in the way to form the hydrogel matix structures, which can be classified in two major groups of chemically- and physically-induced crosslinking.     

Effect of microemulsion in topical sertaconazole hydrogel: in vitro and in vivo study

Purpose: A topical microemulsion (ME)-based hydrogel was developed to enhance permeation of an antifungal drug, sertaconazole (STZL) for effective eradication of cutaneous fungal infection.

Methods: Pseudo-ternary phase diagrams were used to determine the existence of MEs region. ME formulations were prepared with oleic acid, Tween 80, propylene glycol (PG) and water. Carbopol 940 (0.75% w/w) was used for preparation of hydrogel of STZL microemulsion (HSM) and characterized. The in vitro and in vivo evaluation of prepared HSM and commercial cream of STZL were compared.

Results: The viscosity, average droplet size and pH of HSM were 154.23?±?0.54 to 162.52?±?0.21?Pas, 42.3–91.7?nm and 6.9–7.2?, respectively. Permeation rate of STZL from optimized formulation (HSM-4), composed with oleic acid (8.75 % w/w), Tween 80 (33.35% w/w), PG (33.35% w/w) and water (24.55% w/w) was observed higher in compare with other HSMs and commercial cream. HSM-4 was stable, three times higher drug retention capacity in skin than commercial cream and did not caused any erythema or edema based on skin sensitivity study on rabbit. The average zone of inhibition of HSM-4 (23.54?±?0.72?mm) was higher in compare with commercial cream (16.53?±?0.63?mm) against Candida albicans.

Conclusion: The results of study showed that ME played a major role in permeation enhancing and skin retention effect of HSM and the concentration of STZL used for cutaneous fungal infection could be decreased by using ME based hydrogel preparation.     

Stimuli-responsive hydrogels in drug delivery and tissue engineering

Hydrogels are the three-dimensional network structures obtained from a class of synthetic or natural polymers which can absorb and retain a significant amount of water. Hydrogels are one of the most studied classes of polymer-based controlled drug release. These have attracted considerable attention in biochemical and biomedical fields because of their characteristics, such as swelling in aqueous medium, biocompatibility, pH and temperature sensitivity or sensitivity towards other stimuli, which can be utilized for their controlled zero-order release. The hydrogels are expected to explore new generation of self-regulated delivery system having a wide array of desirable properties. This review highlights the exciting opportunities and challenges in the area of hydrogels. Here, we review different literatures on stimuli-sensitive hydrogels, such as role of temperature, electric potential, pH and ionic strength to control the release of drug from hydrogels.     

可注射、组织黏附性PVA/淀粉水凝胶对力学失稳条件下关节软骨退变抑制作用的研究

目的 制备一种仿生正常关节滑液流变学特征的组织黏附性可注射水凝胶,并研究该水凝胶抑制膝关节创伤后软骨退变的效果及其可能的机制。方法 以聚乙烯醇溶液（PVA）、淀粉和氯化钠为主要原料制备可注射、组织黏附性水凝胶（PWN）。通过流变学测试、注射器推出实验、体外降解实验、CCK-8实验、活/死细胞染色、细菌黏附实验、组织黏附实验分别对其流变学性能、可注射性、降解性能、细胞相容性、抗细菌黏附性能和组织黏附性能进行表征。构建大鼠膝关节力学失稳模型,并分为正常组、PWN组、透明质酸组（HA组）与未治疗组,其中PWN组、HA组术后1周时注射PWN与HA进行治疗。治疗4周后取大鼠膝关节标本进行Micro-CT分析和组织学染色分析,对比评估PWN对关节软骨退变的抑制作用。结果 PWN具有良好的细胞相容性和可注射性。此外,相比于HA,PWN的流变学特征更接近正常关节滑液,并且PWN具有缓慢降解的特性、更高的组织黏附性能和抗细菌黏附的能力。动物实验Micro-CT分析结果显示,PWN组软骨下骨的骨密度和骨体积/组织体积均显著高于未治疗组和HA组（P<0.05）。同时,番红快绿染色结果显示,相比于HA组...