HPLC法测定左卡尼汀注射液的含量及有关物质

目的:建立简便快捷的左卡尼汀注射液含量及有关物质测定方法。方法:采用AlltechBrava Amino色谱柱(250 mm×4.6 mm,5μm),柱温40℃,以0.01 mol·L-1磷酸盐缓冲液-乙腈(25∶75)为流动相,流速1.0 m L·min-1,检测波长205 nm。结果:左卡尼汀与各有关物质及降解产物色谱峰分离度良好,各杂质峰互不干扰。左卡尼汀、杂质A、杂质B、杂质C、杂质D质量浓度分别在436.2~2 617、3.5~87.4、2.8~56、1.79~44.8、2.54~50.8μg·m L-1范围内线性关系良好,平均回收率(n=9)分别为100.0%、100.1%、101.6%、95.7%和102.5%,其定量限(S/N=10)分别为167.50、4.20、22.40、60.48和30.48 ng。结论:方法学验证结果表明,本法可用于左卡尼汀注射液的质量控制。     

The relationship between Cd‐induced autophagy and lysosomal activation in WRL‐68 cells

This study shows that Cd induces autophagy in the human's embryonic normal liver cell line (WRL‐68). The expression of LC3B‐II and the mature cathepsin L were analyzed by Western blotting. The autophagosomes and lysosomes were directly visualized by electron microscopy and confocal microscopy analysis in Cd‐exposed WRL‐68 cells. In this study, we first found that autophagy induced the activation of lysosomal function in WRL‐68 cells. The lysosomal activation was markedly decreased when the cells were co‐treated with 3‐MA (an inhibitor of autophagy). Secondly, we provided the evidence that the activation of lysosomal function depended on autophagosome–lysosome fusion. The colocalization of lysosome‐associated membrane protein‐2 (LAMP2) and GFP‐LC3 was significantly reduced, when they were treated with thapsigargin (an inhibitor of autophagosome–lysosome fusion). We demonstrated that deletion or blockage of the autophagosome–lysosome fusion process effectively diminished lysosomal activation, which suggests that lysosomal activation occurring in the course of autophagy is dependent on autophagosome–lysosome fusion. Thirdly, we provided evidence that the activation of lysosomal function was associated with lysosomal acid. We investigated the relationship between autophagosome–lysosome fusion and pH in acidic compartments by visualizing fusion process in WRL‐68 cells. This suggests that increasing pH in acidic compartments in WRL‐68 cells inhibits the autophagosome–lysosome fusion. Finally, we found that the activation of lysosomal function was associated with Ca²⁺ stores and the intracellular Ca²⁺ channels or pumps were possibly pH‐dependent. Copyright © 2015 John Wiley & Sons, Ltd.     

(Ba,Sr)TiO3:RE perovskite phosphors (RE = Dy,Eu): nitrate pyrolysis synthesis,enhanced photoluminescence,and reversible emission against heating

A series of (Ba,Sr)TiO₃ phosphors singly doped with Eu³⁺ and Dy³⁺ were successfully synthesized using the nitrate pyrolysis method at 750 °C. Eu³⁺ or Dy³⁺ single-doped BaTiO₃ retained the tetragonal crystal structure of the host, while the Sr²⁺-substituted (Ba,Sr)TiO₃:RE³⁺ (RE³⁺ = Eu³⁺ or Dy³⁺) experienced a phase transformation from tetragonal to cubic phase with a unit cell shrinkage. For Eu³⁺ doped phosphors, BaTiO₃:xEu³⁺ (x = 0.02–0.10) exhibited red photoluminescence and the highest intensity of emission belonged to the optimal-doped BaTiO₃:xEu³⁺ (x = 8 mol%). Moreover, the substitution of 30 mol% Sr²⁺ for Ba²⁺ (that is Ba_0.7Sr_0.3TiO₃:xEu³⁺, x = 8 mol%) further enhanced the emission intensity of BaTiO₃:xEu³⁺ (x = 8 mol%). For Dy³⁺ doped phosphors, BaTiO₃:xDy³⁺ (x = 0.02–0.10) showed yellow photoluminescence and the highest light intensity was from the optimal-doped BaTiO₃:xDy³⁺ (x = 4 mol%). In addition, the substitution of 20 mol% Sr²⁺ for Ba²⁺ (the phosphor Ba_0.8Sr_0.2TiO₃:xDy³⁺, x = 4 mol%) induced further increase in emission intensity of BaTiO₃:xDy³⁺ (x = 4 mol%). The emission intensities at higher temperature of 100 °C retained about 70% and 90% of the initial values at room temperature (RT) for the optimal BaTiO₃:xEu³⁺ (x = 8 mol%) and BaTiO₃:xDy³⁺ (x = 4 mol%) phosphors, respectively, while the emission intensities at the temperature of 100 °C retained about 60% and 80% of the initial intensities at RT for the optimal Sr²⁺-substituted Ba_0.7Sr_0.3TiO₃:xEu³⁺ (x = 8 mol%) and Ba_0.8Sr_0.2TiO₃:xDy³⁺ (x = 4 mol%) phosphors, respectively. It is worth noting that on cooling down to RT again from 210 °C, the BaTiO₃:xDy³⁺ (x = 4 mol%) phosphor exhibited excellent luminescent thermal stability (with a high activation energy of 0.387 eV) and the strongest recovery (∼95%) of PL emission among the series of phosphors. The as-prepared phosphors with optimal compositions would be good candidates for the applications in lighting, display, and related fields.

Eu³⁺ and Dy³⁺ doped (Ba,Sr)TiO₃ red and yellow phosphors were synthesized respectively. Substituting of Sr²⁺ for Ba²⁺ further enhance emission. BaTiO₃:0.04Dy³⁺ possess an excellent thermal stability and the strongest emission recovery of 95% among the phosphors.     

输入性疟疾的卫生检疫法律义务反思

从全国范围内输入性恶性疟疾个案调查看,输入性疟疾正以点状势态侵入我国。河南国际旅行卫生保健中心调查状况显示,输入性恶性疟疾呈现上升趋势。但是,归国人员的卫生检疫复查困难重重,使得防控结果不稳定。由于目前卫生检疫法律界定模糊,归国人员疾病监测执法不能有效落实,思考目前应该和可以采取的措施认为,除了应该加大传染病的监测力度和强化国际旅行卫生保健知识等健康教育力度外,归国人员应该自律,承担法律义务,负起社会责任,才能有效防止疟疾传入。     

医院医疗器械临床试验的特点及管理对策

该文通过分析中山大学附属第三医院近10年完成的医疗器械临床试验的一般资料,结合临床试验过程中的管理经验,对我院医疗器械临床试验的特点及存在问题进行阐述,并提出相应的管理对策以保证医疗器械试验的质量,提高医院对医疗器械临床试验管理的规范性。     

湖南省永州市1993—2014年艾滋病疫情特点

目的分析永州市1993—2014年艾滋病疫情特点,为制定人免疫缺陷病毒(HIV)/获得性免疫缺陷综合征(AIDS)预防和控制策略提供科学依据。方法采用描述流行病学方法,对永州市1993—2014年艾滋病疫情进行统计分析。结果永州市1993—2014年累计报告HIV/AIDS病例2 917例,报告病例数逐年上升;男女比例为2.30∶1;20~49岁青壮年占52.04%,≥50岁者占46.76%,近年≥50岁人群所占比例上升明显;感染途径以性传播为主,占88.48%,其中男男同性传播占2.64%。结论永州市要进一步加大艾滋病知识宣传力度,切实落实高危人群行为干预各项措施;将端口下移,扩大检测范围,以有效防控艾滋病的传播与流行。     

H7N9禽流感病毒疫苗及其预防控制

<正>禽流感病毒有6个内部基因来自于H9N2,部分血凝素(hemagglutinin,HA)和神经氨酸酶(neuramidinase,NA)基因源自H7N3和H1N9。禽流感病毒能够感染人类,可能与HA和NA基因发生了Q226L和E627K关键位点突变有关,这两个突变被认为是病毒适应人类气道上皮的表现。此外,H7N9具有哺乳动物流感病毒的特性,如HA蛋     

口腔专科医院医务人员手卫生依从性干预效果

目的提高口腔专科医院医务人员的手卫生依从性,有效降低医院感染率。方法依照世界卫生组织推荐的《手卫生指南》及《手卫生实施方案》,制订系统、循序渐进的口腔专科医院手卫生促进方案,分5个步骤进行:全院戒备、基线调查、实施改进、跟踪调查和回顾分析。对比手卫生促进活动前后医务人员的手卫生依从性。结果通过手卫生促进活动,医务人员手卫生知识问卷调查平均得分由之前的58.33分提高至77.40分,提升了32.69%;平均手卫生依从率由24.28%(59/243)上升至49.81%(133/267),差异有统计学意义(χ2=35.331,P=0.000);5个手卫生时刻的手卫生状况也有较大改善。结论手卫生促进活动对口腔专科医院医务人员的手卫生依从性有显著影响。     

藁本内酯对谷氨酸诱导的PC12细胞凋亡的保护作用

研究藁本内酯对谷氨酸诱导PC12细胞凋亡的保护作用。采用MTT比色法检测细胞存活率;Annexin V-FITC/propidium iodide(PI)双染法流式细胞术(flow cytometry,FCM)检测细胞凋亡率;Fluo-3/AM荧光染色法检测钙离子含量;Western blot法检测线粒体和胞浆中细胞色素C(cytochrome C,Cyt C)及凋亡相关蛋白Caspase-3、Bcl-2、Bax的表达。结果显示,谷氨酸具有细胞毒性,其半数抑制浓度(IC50)为15 mmol·L-1;不同浓度藁本内酯(1、5、15μmol·L-1)预处理可显著提高细胞存活率。与正常对照组相比,谷氨酸单独给药组的细胞凋亡率为13.39%;藁本内酯给药组(1、5、15μmol·L-1)使细胞的凋亡率分别减少到9.06%、6.48%和3.82%。并且藁本内酯可以显著减少谷氨酸所致的钙离子内流,Western blot结果显示,藁本内酯可能通过减少线粒体Cyt C的释放,抑制Caspase-3活性,同时升高Bcl-2/Bax比值来保护谷氨酸诱导的PC12细胞凋亡。结果表明,藁本内酯对谷氨酸诱导PC12细胞的凋亡具有保护作用。该保护作用可能与抑制细胞内钙离子内流及阻断Cyt C从线粒体释放入胞浆有关。