Docetaxel-loaded nanoparticles based on star-shaped mannitol-core PLGA-TPGS diblock copolymer for breast cancer therapy

A star-shaped biodegradable polymer, mannitol-core poly(d,l-lactide-co-glycolide)-d-α-tocopheryl polyethylene glycol 1000 succinate (M-PLGA-TPGS), was synthesized in order to provide a novel nanoformulation for breast cancer chemotherapy. This novel copolymer was prepared by a core-first approach via three stages of chemical reaction, and was characterized by nuclear magnetic resonance, gel permeation chromatography and thermogravimetric analysis. The docetaxel-loaded M-PLGA-TPGS nanoparticles (NPs), prepared by a modified nanoprecipitation method, were observed to be near-spherical shape with narrow size distribution. Confocal laser scanning microscopy showed that the uptake level of M-PLGA-TPGS NPs was higher than that of PLGA NPs and PLGA-TPGS NPs in MCF-7 cells. A significantly higher level of cytotoxicity was achieved with docetaxel-loaded M-PLGA-TPGS NPs than with commercial Taxotere®, docetaxel-loaded PLGA-TPGS and PLGA NPs. Examination of the drug loading and encapsulation efficiency proved that star-shaped M-PLGA-TPGS could carry higher levels of drug than linear polymer. The in vivo experiment showed docetaxel-loaded M-PLGA-TPGS NPs to have the highest anti-tumor efficacy. In conclusion, the star-like M-PLGA-TPGS copolymer shows potential as a promising drug-loaded biomaterial that can be applied in developing novel nanoformulations for breast cancer therapy.     

Fabrication and characterization of biomimetic collagen–apatite scaffolds with tunable structures for bone tissue engineering

The objective of the current study is to prepare a biomimetic collagen–apatite scaffold for improved bone repair and regeneration. A novel bottom–up approach has been developed, which combines a biomimetic self-assembly method with a controllable freeze-casting technology. In this study, the mineralized collagen fibers were generated using a simple one-step co-precipitation method which involved collagen self-assembly and in situ apatite precipitation in a collagen-containing modified simulated body fluid (m-SBF). The precipitates were then subjected to controllable freeze casting, forming scaffolds with either an isotropic equiaxed structure or a unidirectional lamellar structure. These scaffolds were comprised of collagen fibers and poorly crystalline bone-like carbonated apatite nanoparticles. The mineral content in the scaffold could be tailored in the range 0–54 wt.% by simply adjusting the collagen content in the m-SBF. Further, the mechanisms of the formation of both the equiaxed and the lamellar scaffolds were investigated, and freezing regimes for equiaxed and lamellar solidification were established. Finally, the bone-forming capability of such prepared scaffolds was evaluated in vivo in a mouse calvarial defect model. It was confirmed that the scaffolds well support new bone formation.     

128层螺旋CT联合心电门控技术在支气管动脉成像中的应用

目的：探讨128层螺旋CT联合心电门控扫描技术在支气管动脉成像中的临床应用价值。方法：回顾性分析我院124例次胸部CT血管成像（CTA）数据,其中72例次行常规胸部CTA扫描数据列入对照组,52例次采用心电门控技术扫描数据列入观察组,对比分析观察两组支气管动脉的开口位置、走行、与相邻组织之间的解剖关系以及支气管动脉显示的清晰度。结果：对照组中33．33％（24／72）支气管动脉显示较清晰,58．33％（42／72）支气管动脉显示模糊,8．33％（6／72）没有发现支气管动脉;观察组52例次支气管动脉全部显示,其中86．54％（45／52）支气管动脉显示清晰,13．46％（7／52）支气管动脉显示模糊。结论：128层螺旋CT联合心电门控扫描技术与常规胸部血管成像相比,能更清晰地显示支气管动脉开口位置、形态、走行及其与相邻组织的关系,对支气管动脉源性疾病的治疗,特别是介入治疗术前评估有重要的临床应用价值。     

生理学多媒体精品课件的制作与应用效果

多媒体辅助教学（CAI）已经广泛应用于生理学教学中,使教学效率与教学质量都显著提高。本文探讨了如何制作优质高效、个性鲜明的生理学多媒体精品课件,并恰当运用,期望能够充分发挥CAI的积极作用,更进一步提高生理学教学趣味与质量。关键词     

青岛市市南区小学生群体性窝沟封闭质量评价

目的研究群体性窝沟封闭的质量。方法参照第三次全国口腔健康流行病学抽样调查方案中分层、整群和随机抽样相结合的方法,从青岛市市南区4所学校抽取由青岛市口腔医院医务人员做过第一恒磨牙窝沟封闭的2～5年级小学生,各年级人数均为400名,男女各半。检查第一恒磨牙窝沟封闭剂的保留、脱落情况,填写统一记录表,对所得的数据进行统计学分析。结果随着窝沟封闭术后时间的延长,封闭剂的脱落率逐渐增加,封闭剂完全保留率逐渐降低;窝沟封闭术后3年,封闭剂完全保留率为60.0%,部分脱落率为24.0%,完全脱落率为16.0%。封闭剂在颊舌面的脱落率明显高于牙合面脱落率(P<0.05)。结论窝沟封闭后,随着时间延长,封闭剂的保留率降低,颊舌面封闭剂脱落率高于牙合面脱落率。窝沟封闭后应该加强复查复治,以保证防龋效果。     

A Decrease in the Percentage of CD3+ Cells Is Correlated With Clinical Improvement During Plasmapheresis in Patients With Myasthenia Gravis

Plasmapheresis not only removes circulating antibodies but also modulates cellular immunity, including lymphocyte subsets. To investigate the effect of double‐filtration plasmapheresis (DFPP) on the ratio of lymphocyte subsets in patients with myasthenia gravis (MG), we examined the percentages of B‐cells, T‐cells, T helper (Th) cells, T suppressor (Ts) cells, natural killer (NK) cells, NKT cells, and Th/Ts ratio before and after a single DFPP session and after a course of DFPP. A total of 26 patients were recruited; their peripheral blood lymphocyte subsets were assayed using flow cytometry. After a single session of DFPP treatment, the percentages of T‐cells (P = 0.0200), Th cells (P = 0.0178), and the Th/Ts ratio (P = 0.0309) decreased significantly, whereas the percentage of NK cells (P = 0.0007) increased significantly. More importantly, after one course of DFPP treatment, the reduced clinical quantitative MG (QMG) score was correlated with the decrease of the percentage of T‐cells (r = 0.5005, P = 0.0092). Fourteen thymectomized MG patients had decreased percentages of T‐cells (P = 0.0304) and Th cells (P = 0.0444), whereas they had increased NK cells (P = 0.0197) after a single DFPP session. Here, transiently decreased percentages of T‐cells after the full DFPP course could enhance the effectiveness of plasmapheresis for MG patients.