克柔假丝酵母菌通过Dectin-1/Syk信号通路活化巨噬细胞自噬

目的探究Dectin-1/Syk信号通路在克柔假丝酵母菌激活RAW264.7细胞自噬中的作用。方法以特异性抗体封闭RAW264.7细胞表面TLR-2、TLR-4及Dectin-1受体,免疫蛋白印记检测克柔假丝酵母菌刺激后LC3II的表达量;通过白皮杉醇及Raf-1抑制剂分别阻断RAW264.7细胞Syk及Raf-1磷酸化,观察对克柔假丝酵母菌激活细胞自噬的影响;采用SiMi Transfection Reagents转染Atg5siRNA,检测不同时间段RAW264.7细胞对克柔假丝酵母菌的杀菌率。结果封闭细胞膜Dectin-1、阻断Syk磷酸化显著抑制克柔假丝酵母菌诱导RAW264.7细胞LC3II的表达,而封闭细胞膜TLR-2或TLR-4,以及阻断Raf-1磷酸化对于克柔假丝酵母菌刺激下LC3II的表达无显著影响。敲低Atg5后RAW264.7细胞在感染6h后对克柔假丝酵母菌的杀菌率显著降低。结论 Dectin-1/Syk信号通路介导了克柔假丝酵母菌激活RAW264.7细胞自噬,并且自噬功能参与了该细胞对克柔假丝酵母菌的杀灭作用。     

烟曲霉感染时内在化Dectin-1介导巨噬细胞自噬活化

目的探究在烟曲霉感染时Dectin-1是否内在化表达并介导了巨噬细胞的自噬活化,初步明确其作用机制。方法采用Western blot法和免疫荧光技术,观察经β-1,3-D-葡聚糖酶消化前后的烟曲霉孢子刺激下,RAW264.7细胞内Dectin-1与LC3Ⅱ的表达与定位,通过DCFH-DA探针检测消化β-葡聚糖对活性氧(ROS)生成的影响。结果烟曲霉孢子刺激后RAW264.7细胞的Dectin-1与LC3Ⅱ表达水平显著升高,同时二者呈斑点状聚集并共定位于烟曲霉孢子表面;消化β-葡聚糖后Dectin-1与LC3Ⅱ表达量降低,荧光斑点消失,并且ROS的生成受到抑制。结论烟曲霉感染时Dectin-1提高自身内在化表达并诱导了巨噬细胞自噬功能的活化。     

Bel-7402细胞通过自噬逃避FAS/ActD诱导的凋亡

为了探究FAS抗体与放线菌素D（actinomycin D,ActD）诱导肝癌细胞Bel-7402凋亡的作用机制,通过自噬阻断剂3-MA的作用,来探讨自噬与凋亡的关系.利用电子显微镜和流式细胞仪观察细胞自噬及凋亡.结果表明,FAS/ActD在诱导细胞凋亡的同时伴有细胞自噬现象,在3-MA作用下,FAS/ActD所诱导的细胞自噬体减少,而凋亡现象严重.并且通过流式细胞仪分析表明,3-MA明显增高FAS/ActD所诱导的细胞凋亡率. Western印迹分析进一步显示,FAS/ActD能引起caspase-3激活产生断裂,同时刺激LC3和BECN1表达,而3-MA作用后自噬体减少,同时LC3和BECN1表达降低,但是caspase-3断裂带表达明显增加.以上结果提示,FAS/ActD诱导的Bel-7402细胞凋亡的同时伴有细胞自噬,Bel-7402细胞通过自噬逃避FAS/ActD诱导的凋亡.     

不同形态的烟曲霉对巨噬细胞自噬水平的影响

目的探究烟曲霉静息孢子、膨胀孢子以及菌丝对巨噬细胞自噬水平的影响。方法培养烟曲霉并收获静息孢子,在沙保弱液体培养基中振荡不同时间获得膨胀孢子及菌丝。以3种形态的烟曲霉分组处理RAW264.7细胞,免疫印迹法检测LC3BⅡ蛋白的表达量,逆转录PCR检测自噬相关蛋白Atg5、Atg7、Atg12 mRNA的转录水平。观察不同形态的烟曲霉刺激GFP-LC3B-RAW264.7细胞后GFP-LC3B的表达与定位。结果膨胀的烟曲霉孢子及菌丝刺激巨噬细胞后LC3BⅡ表达水平升高;Atg5与Atg12 mRNA的转录均明显增高,Atg7转录水平无显著变化;膨胀孢子诱导LC3B呈斑点样聚集并与之共定位,烟曲霉菌丝刺激后自噬体增多。结论烟曲霉膨胀孢子与菌丝能显著提高巨噬细胞自噬水平,静息的分生孢子不能引起巨噬细胞自噬功能的应答。     

维生素D对烟曲霉感染的肺巨噬细胞 自噬机制的初步研究

目的探究维生素D在鼠肺细胞感染烟曲霉后对细胞自噬的影响。方法用一定量的烟曲霉活化孢子感染细胞后,一组细胞加入维生素D(维生素D组),一组细胞加入生理盐水,感染一定时间后用溶酶体探针检测自噬相关分子的表达;收集各组细胞并裂解细胞,离心取上清,用Western-blot法检测上清液中的LC3BII、Dectin-1及ROS的表达水平。结果活化的孢子感染肺巨噬细胞后,维生素D组自噬体与溶酶体共定位减少、吞噬孢子的速率在减少以及ROS水平降低,其对应的胞内Dectin-1、ROS、LC3BII减少且差异有统计学意义。结论烟曲霉感染肺巨噬细胞后,维生素D可通过减弱细胞自噬体与溶酶体的融合并下调自噬信号通路蛋白的表达以达到抵抗烟曲霉感染的作用。     

ESAT6通过mTOR抑制自噬并促进BCG增殖

目的研究mTOR在结核杆菌毒力因子ESAT6诱导的自噬抑制以及促进BCG增殖中的作用。方法 PCMV-HA-ESAT6质粒转染Raw264.7细胞,用蛋白免疫印迹检测LC3、P62、P-mTOR和P-70S6K表达水平;用mTOR阻断剂Torin1联合ESAT6转染以及分别作用于Raw264.7细胞后,免疫印迹检测P62和P-mTOR表达水平,LysoTracker Red染色观察溶酶体变化,BCG增殖实验计数各组菌落数。结果 ESAT6转染细胞后,细胞P62、P-mTOR和P-70S6K表达水平显著增高,LC3I完成向LC3II的转化;联合Torin1的ESAT6转染组和Torin1处理组的P-mTOR和P62无显著变化,溶酶体无变化,BCG菌落数减少。结论 ESAT6诱导的自噬抑制和BCG的增殖依赖于mTOR的活化。     

缺氧复氧诱导自噬基因表达对滋养细胞生长的影响与机制

为探索子痫前期孕妇胎盘病变的发病机制,我们模拟体内缺血再灌注微环境,在体外建立胎盘滋养细胞HTR8/SVneo缺氧复氧模型,以探究缺氧复氧对细胞自噬的诱导作用及对细胞生长的影响。将实验分为对照组、缺氧复氧组及自噬抑制剂3-MA+缺氧复氧组,应用吖啶橙染色及LC3-Ⅱ免疫荧光染色检测经处理24 h后细胞自噬水平,MTT法检测细胞增殖能力,Real time PCR检测自噬基因Beclin-1、LC3-Ⅱ的表达,Western blot分析相应自噬蛋白的表达。结果显示缺氧复氧组HTR8/SVneo细胞自噬水平明显升高(p0.01),伴随Beclin-1、LC3-Ⅱ基因及蛋白表达显著增高(p0.01),细胞增殖同时显著受抑(p0.01),而加入3-MA后缺氧复氧组细胞自噬水平明显受抑(p0.01),Beclin-1、LC3-Ⅱ基因及蛋白表达显著下降(p0.01),细胞增殖能力显著提高(p0.01)。这表明滋养细胞HTR8/SVneo在缺氧复氧环境中启动细胞自噬,过度自噬时可能通过诱导Ⅱ型程序性死亡影响细胞增殖,当自噬被抑制后,细胞增殖能力明显恢复。     

肺泡Ⅱ型上皮细胞自噬体与结核分枝杆菌相互作用的研究

目的:检测LC3在肺泡Ⅱ型上皮细胞A549上的表达情况,及结核分枝杆菌刺激后对其表达的影响,探讨自噬在结核分枝杆菌感染上皮细胞中所起的作用。方法:体外培养肺泡Ⅱ型上皮细胞A549,在结核分枝杆菌感染A549细胞0h,24h分别提取RNA,采用RT-PCR的方法检测LC3mRNA的表达情况。采用凋亡坏死染色试剂盒在结核分枝杆菌感染24h后检测对照组,3-MA组,MTB组和3-MA+MTB组的细胞坏死情况。在结核分枝杆菌感染A549细胞4h,8h,16,24h采用Non-Radioactive Cytocity Assay的方法检测对照组,3-MA组,MTB组和3-MA+MTB组上清液LDH的OD值。结果:LC3在肺泡Ⅱ型上皮细胞显著表达,结核分枝杆菌感染后LC3表达降低。细胞凋亡和坏死染色结果显示空白组和3-MA组没有明显差异(P>0.05),MTB组和3-MA+MTB组有明显差异(P<0.05)。LDH检测显示MTB组和3-MA+MTB组上清液LDH的OD值数据两两之间有明显差异(P<0.05)并且有时间依赖性。结论:肺泡II型上皮细胞自噬体在抵抗结核分枝杆菌的感染过程中起一定的作用。     

结核分枝杆菌eis基因对鼠巨噬细胞Raw264．7白噬影响的研究

目的探讨结核分枝杆菌eis基因对巨噬细胞自噬的影响。方法将鼠巨噬细胞Raw264．7以自噬体荧光表达质粒GFP-LC3转染,将含eis基因的重组耻垢分枝杆菌MS—pmv261-eis与不含eis基因的耻垢分枝杆菌MS—pmv261分别感染宿主巨噬细胞,透射电镜下观察自噬小体形成情况,荧光显微镜下观察自噬荧光并计数,Westernblot检测如基因表达的蛋白及自噬蛋白LC3-Ⅱ的表达水平。结果结核分枝杆菌eis基因可抑制感染宿主细胞自噬小体的形成,并显著抑制自噬荧光小点形成（P〈0．05）,显著降低了自噬蛋白LC3-Ⅱ表达水平。结论结核分枝杆菌e曲基因对Raw264．7细胞自噬有抑制作用。     

雷公藤红素通过激活LXRα/ABCA1通路和细胞自噬抑制巨噬细胞脂质蓄积

巨噬细胞源性泡沫细胞转化被认为是动脉粥样硬化(atherosclerosis,AS)形成与发展的早期变化,其细胞内蓄积的过量脂质可通过促进血管内膜生长与坏死核形成,继而诱发斑块破裂及血栓形成等严重后果.近期研究发现,雷公藤红素可显著调节脂质代谢,对泡沫细胞转化进程具有潜在的治疗意义.本研究表明,雷公藤红素(Celasrol,CeT)呈浓度依赖性减少巨噬细胞Raw264.7内的脂滴积蓄,并上调胆固醇转运关键分子ABCA1、LXRA蛋白质表达.进一步研究显示,CeT可逆转ABCA1敲低介导的脂质蓄积与ABCA1表达下调.此外,CeT处理Raw264.7细胞24 h时观察到自噬标志物LC3Ⅱ/Ⅰ增加、p62减少,且采用自噬抑制剂3MA可恢复细胞内脂质水平.综上,CeT可能通过上调LXRα/ABCA1信号及激活荷脂细胞自噬,抑制巨噬细胞内脂质蓄积.因此,深入探究CeT在巨噬细胞源性泡沫细胞转化及AS发生发展中的作用,是研究AS治疗新的着力点,并为药物干预提供新的靶点.     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

医疗机构合理用药评价模型的构建研究

目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.