Nicotine protects rat chondrocytes against interleukin-1beta-induced apoptosis through PI3K/Akt signaling

目的：探索尼古丁对IL-1β诱导的大鼠OA软骨细胞（模拟OA软骨细胞）的调节作用，观察是否能够通过激活软骨细胞内PI3K/Akt信号通路而抑制OA软骨细胞调亡、维持其存活；同时结合大鼠OA动物模型检测尼古丁对OA软骨组织损伤的影响，为将来临床上应用尼古丁预防与治疗OA的可能机制提供理论依据。 方法：体外实验：（1）软骨细胞分离培养：从新生大鼠关节软骨中分离出软骨细胞，使用特殊染色及免疫组化对其进行鉴定，并使其与软骨细胞凋亡诱导调节剂IL-1β(10ng/ml)共培养2小时，模拟体外OA软骨细胞。（2）软骨细胞生存能力检测：经尼古丁处理后，四甲基偶氮唑盐微量酶反应比色法（MTT）检测软骨细胞活...Objective. To identify the effects of nicotine on chondrocyte apoptosis in rat osteoarthritis (OA) which induced by IL-1β and the mechanism in vitro and in vivo. To observe that it is feasible to inhibite chondrocyte apoptosis and keep chondrocyte survival in rat osteoarthritis (OA) via activating PI3K/Akt signaling pathway. Meanwhile, combining together that the protective effect of nicotine on ...学位：医学硕士院系专业：医学院临床医学系_外科学学号：2452009115299

人骨髓间充质干细胞分离培养方法的改进

背景:当前分离培养骨髓间充质干细胞方法的有多种,但在外科手术中进行获取的方法仍然较少,而外科分离所得细胞对于相应疾病的具有揭示原因和提供研究线索的价值。目的:在骨科手术中以直接贴壁差速贴壁分离培养纯化与鉴定骨髓间充质干细胞。方法:在骨科关节置换等大手术中吸取少量人骨髓血,采用直接贴壁法分离骨髓间充质干细胞,在贴壁后36～48h行洗盘处理,并通过长期体外培养,特定培养基自身的筛选作用对细胞进行筛选,当细胞生长达到足量时进行鉴定。结果与结论:采用直接贴壁法能够在长骨髓腔内混合血中分离培养骨髓间充质干细胞并形成集落,其形态学表现和表面分子经鉴定符合骨髓间充质干细胞特点,能够获得符合要求的人骨髓间充质干细胞,从而进行后续实验

核因子-κB参与人骨髓间充质干细胞的增殖上调研究

目的探讨核因子(NF)-κB在人类骨髓间充质干细胞增殖调节中的作用。方法体外分离培养人骨髓间充质干细胞后:①蛋白免疫印迹法(Western-blot)观察脂多糖(LPS)作用下NF-κB活性亚型p65及其活性形式磷酸化p65的表达水平随时间变化的情况;②Western-blot法观察NF-κB活性抑制剂PDTC对磷酸化p65表达水平影响;③Western-blot法检测PDTC与LPS单独及共同作用下,细胞增殖标志物增殖细胞核抗原(PCNA)表达水平的变化;④MTT法检测PDTC与LPS作用下细胞增殖水平的变化。结果 LPS可显著上调p65及其磷酸化状态的表达水平,上调作用可被PDTC部分地抑制;NF-κB上调后可提高细胞增殖蛋白PCNA的表达水平,并促进细胞增殖。结论初步证实了NF-κB参与人骨髓间充质干细胞增殖的调节

Influence of salinity on the ingestion rate of exotic species Mytilopsis sallei

外来物种沙筛贝(MyTIlOPSIS SAllEI)是一种滤食性软体动物双壳类,它有着很快的生长速度和很强的摄食能力.为了探索沙筛贝在不同盐度下对微藻的摄食能力,采用颗粒计数仪,测定了沙筛贝在15、20、25、30、35等5个盐度梯度下对等鞭金藻(ISOCHrySIS gAlbAnA)和小球藻(CHlOrEllA VulgArIS)的摄食率,比较了不同沙筛贝个体大小对小球藻的摄食率.结果表明,沙筛贝对等边金藻和小球藻的摄食率均在盐度25时达到最大,分别为3.42x104CEllS/(Ind.H)和6.72x104CEllS/(Ind.H).沙筛贝对等边金藻的摄食率随时间推移而降低,一是因为沙筛贝摄食率随着藻类密度的降低而减小,二是当海水盐度下降,沙筛贝渗透压改变,导致了进入其外套腔的海水体积的减少,从而摄食率也减少.个体较大(壳长2.8~3.5 CM)的沙筛贝对小球藻的摄食率明显高于个体较小(壳长1.7~2.4 CM)的沙筛贝的摄食率,这与其他贝类的研究结果是一致的.The exotic species Mytilopsis sallei is a filter-feeding bivalve mollusk.It has a fast growth rate and high ingestion ability.In order to explore the ingestion ability of Mytilopsis sallei to microalgae at different salinity,Particle Counter was used to determine the level of microalgae and the ingestion rates of Mytilopsis sallei on Isochrysis galbana and Chlorella vulgaris at salinity of 15,20,25,30,35 and at different sizes of Mytilopsis sallei.The results showed that the ingestion rates of Mytilopsis sallei on 2 microalgae were high at salinity of 25[the mean ingestion rates on Isochrysis galbana and Chlorella vulgaris were 3.42×104 cells/(ind·h) and 6.72 cells/(ind·h)].The ingestion rate of Mytilopsis sallei on Isochrysis galbana decreased with time.The first reason is due to the decrease of microalgae density.The second reason is that the osmotic pressure of Mytilopsis sallei was changed when salinity decreased,which resulted in less seawater entered into mantle cavity of Mytilopsis sallei.The larger individuals of Mytilopsis sallei is(shell length between 2.8 cm and 3.5 cm),the higher ingestion rate of Mytilopsis sallei on Isochrysis galbana is.The result was consistent with the ingestion rate of other shellfish.国家自然科学基金资助项目(40776066);厦门大学海洋与环境学院凌峰计划资助项

Significant broadband extinction abilities of bioaerosols

Bioaerosol, an important constituent of the atmosphere, can directly affect light radiation characteristics due to absorption and scattering effects. Current research lacks a reasonable explanation for the extinction abilities of bioaerosols in a broadband. Herein, we measured the reflectance spectra of 12 common biomaterials and calculated their complex refractive indexes. The peaks of the imaginary part of the complex refractive indexes are located at wavelengths of approximately 0.7, 2.7, 6.1 and 9.5 μm. Based on photographs of the floating structures of bioaerosols, we constructed a model for calculating the extinction abilities of bioaerosols in the wavelength range of 240 nm to 14 μm. Taking AN02 spores as an example, absorption was found to account for more than 90% of the total extinction. In addition, the theoretical calculations and experimental data of transmittance corresponding to the smoke box show that bioaerosol exhibits significant broadband extinction ability from UV to IR bands, which provides new directions for the development of broadband light attenuation materials.生物气溶胶是大气的重要组成部分, 因其吸收和散射效应, 可直接影响光辐射特性. 当前对于生物气溶胶是否具有宽波段消光特性 的研究还不够充分. 本文中, 我们测量了12种常见生物材料在240 nm–14 μm波段内的反射光谱, 并结合K-K算法计算了不同生物气溶胶材 料的复折射率. 我们发现, 不同种质生物气溶胶的吸收峰具有共性, 位于约0.7, 2.7, 6.1和9.5 μm处. 基于烟幕箱中生物气溶胶漂浮状态实际 结构的照片, 我们构建了模型计算240 nm–14 μm波长范围内生物气溶胶的消光能力. 以AN02孢子为例, 我们发现吸收作用占AN02孢子群 消光总量的90%以上. 此外, 我们对比了生物气溶胶理论计算透过率与大型烟幕箱实测透射率数据, 理论计算和实验验证都显示生物气溶 胶在紫外到红外波段具有显著的宽波段消光能力. 这一发现为宽波段消光材料的发展提供了新的研究方向

Terahertz filters based on frequency selective surfaces for high-speed terahertz switch

Localized plasmon modes are excited and probed in a large-area grating-gate GaN/AlGaN high-electron-mobility transistor structure embedded in a Fabry-Perot cavity using a terahertz time-domain spectroscopy (THz-TDS) at cryogenic temperature. Determined by the length of grating finger and the electron concentration, the frequency of localized plasmon modes can be continuously tuned by the gate voltage in the spectral range from 0.1 THz to 1.5 THz. When the plasmon frequency is tuned to be in resonance with the terahertz Fabry-Perot cavity mode, a strong coupling between the plasmon mode and the cavity mode is observed and the terahertz plasmon-polaritons are formed in such a cavity-coupled two-dimensional electron system. The electromagnetic simulations have confirmed the strong coupling between them