丙烯酸树脂水性包衣工艺制备氯化钾缓释片的研究

目的:研究氯化钾缓释片的优化工艺.方法:采用丙烯酸树脂水性包衣工艺,通过体外溶出试验对工艺参数进行筛选.结果:包衣后热处理、包衣处方因数(聚合物配比、增塑剂、包衣增重等)都对缓释片释放度有影响,而浆法转速和介质渗透压对缓释片释放度几乎无影响.结论:本研究缓释片的体外释放按零级模式释药.     

吲哚美辛肠溶包衣微丸的制备及其释放度的研究

 目的:制备吲哚美辛肠溶包衣徽丸，考察其释放特性。方法:采用正交试验设计筛选徽九的处方、工艺参数，用滚动凝聚法制备素丸，用沸腾包衣技米制备微丸，通过溶出试验考察其释放特性。结果:以优选处方、工艺制备 的徽丸在规定的酸性介质中几乎不释放，而在碑酸盐缓冲液中则释放80%以上。结论:本品处方合理，制备工艺简单，能达到肠溶目的，可降低或消除吲哚美辛在临床上使用的毒副作用。     

乙基纤维素作为包衣材料在缓释盐酸苯丙醇胺树脂上的应用

 目的：考察影响药树脂体外溶出的因素，制备缓释盐酸苯丙醇胺(PPA·HCl)树脂。方法：以不同粘度规格的乙基纤维素(EC)为包衣膜材料制备缓释PPA·HCl树脂，以体外溶出试验，考察了树脂粒径、EC粘度、EC包衣增重百分率、EC分散介质(水或乙醇)以及体外释放介质的pH值和离子强度对上述缓释药树脂体外溶出的影响。结果：上述因素对药树脂的释药均有不同程度的影响，以EC 200 Pa·s包衣增重达150 g·kg^-1时，包衣药树脂在0.1 mol·L^-1HCl中的释放符合美国药典23版缓释PPA·HCl胶囊的要求。结论：用乙基纤维素为包衣膜材料，可以制备缓释PPA·HCl树脂。     

94例消化性溃疡患者舌象分析

目的观察消化性溃疡患者舌象特征.方法选择94例符合临床诊断及中医辨证分型标准的消化性溃疡患者,同步记录其舌质与舌苔变化.结果消化性溃疡患者各证型的舌象特征分布较广,且多数证型的主要舌象与证型的内在病理本质相吻合.结论舌象反映消化性溃疡各证型的内在病机变化,是临床诊治过程中确定分型证候的客观依据.     

Improvement to the Corrosion Resistance of Ti-Based Implants Using Hydrothermally Synthesized Nanostructured Anatase Coatings

The electrochemical behavior of polycrystalline TiO₂ anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected.     

Influence Factors and Prediction Model of Bond Strength of Tunnel Fireproof Coating under Freeze–Thaw Cycles

The freeze–thaw resistant performance of a tunnel fireproof coating (TFC) has an important impact on bonding property and durability. The influence of redispersible emulsion powder, polypropylene fiber and air-entraining agent on TFCs was studied. Transverse fundamental frequency and ultrasonic sound velocity were used to evaluate the damage degree of TFC, and the mechanism was revealed by SEM and pore structure. The results show that the most beneficial effect on bond strength of TFC is redispersible emulsion powder, followed by air-entraining agent, and then polypropylene fiber. After freeze–thaw cycles, the cumulative pore volume of micropores in the TFC increases obviously, while the porosity of macropores does not change significantly. A prediction model was proposed, which can calculate the bond strength from the damage degree of TFC under freeze–thaw cycles. The achievement can promote the application of TFC in cold regions.     

Wear Behavior of Fiber Laser Textured TiN Coatings in a Heavy Loaded Sliding Regime

In heavy loaded mating components, such as sliders and sliding bearings, guaranteeing the efficiency of lubricant films for long times during severe service conditions is very complicated. In this work, the benefits deriving from the use of fiber laser sources for surface texturing of very thin TiN coatings in severe wear working conditions were demonstrated. Evaluations of the laser textured dimples shape, geometry and density are given. Wear performance of the fiber laser textured surfaces was evaluated in discontinuous oil lubricated conditions with a flat contact. High normal load and low sliding speed were applied. Comparison tests were also performed on commercial TiN and WC/C coatings. In terms of average wear volume and maximum wear depth, Laser Surface Texturing of TiN provided respectively a 70% and a 45% reduction if compared to plain TiN. If compared to WC/C the wear resistance gains were lower but LST TiN maintained such benefits for longer wear runs. SEM analysis also revealed that the laser interaction provided a localized thermal cracking to the TiN coating. However, the sliding action caused very limited and localized coating fragmentation or delamination.     

Harmful at non-cytotoxic concentrations: SiO2-SPIONs affect surfactant metabolism and lamellar body biogenesis in A549 human alveolar epithelial cells

The pulmonary delivery of nanoparticles (NPs) is a promising approach in nanomedicine. For the efficient and safe use of inhalable NPs, understanding of NP interference with lung surfactant metabolism is needed. Lung surfactant is predominantly a phospholipid substance, synthesized in alveolar type II cells (ATII), where it is packed in special organelles, lamellar bodies (LBs). In vitro and in vivo studies have reported NPs impact on surfactant homeostasis, but this phenomenon has not yet been sufficiently examined. We showed that in ATII-like A549 human lung cancer cells, silica-coated superparamagnetic iron oxide NPs (SiO₂-SPIONs), which have a high potential in medicine, caused an increased cellular amount of acid organelles and phospholipids. In SiO₂-SPION treated cells, we observed elevated cellular quantity of multivesicular bodies (MVBs), organelles involved in LB biogenesis. In spite of the results indicating increased surfactant production, the cellular quantity of LBs was surprisingly diminished and the majority of the remaining LBs were filled with SiO₂-SPIONs. Additionally, LBs were detected inside abundant autophagic vacuoles (AVs) and obviously destined for degradation. We also observed time- and dose-dependent changes in mRNA expression for proteins involved in lipid metabolism. Our results demonstrate that non-cytotoxic concentrations of SiO₂-SPIONs interfere with surfactant metabolism and LB biogenesis, leading to disturbed ability to reduce hypophase surface tension. To ensure the safe use of NPs for pulmonary delivery, we propose that potential NP interference with LB biogenesis is obligatorily taken into account.