转香蕉MaASR1基因的拟南芥株系在干旱胁迫条件下的表达谱分析

干旱是最重要的环境胁迫,香蕉MaASR1基因在植物响应逆境胁迫时发挥着重要作用,为了深入研究MaASR1基因的过表达使拟南芥抗旱的分子机制,利用全基因组表达芯片来广谱的筛选MaASR1基因转入后自然条件下及干旱处理条件下差异基因的表达情况。对基因芯片的结果进行了详细的生物信息学分析及相关基因的RT-PCR验证,结果表明MaASR1基因异源表达的拟南芥株系在自然生长条件下共有747个差异基因,其中上调基因559个,下调基因188个;在干旱胁迫条件下共得到653个差异基因,其中上调基因256个,下调基因397个;MaASR1基因的转入可以通过影响激素、光合作用、锌指蛋白及不依赖ABA途径的DREB2A等相关基因的表达来提高拟南芥的抗旱性。为解析MaASR1基因作为转录因子提高植物抗旱能力的分子机制奠定基础。     

过量表达拟南芥CAT提高烟草对气体甲醛的吸收和抗性

为提高植物对甲醛的吸收和耐受,利用拟南芥CAT的编码区构建植物过表达载体pk2-Prbc S-*T-CAT,在野生型(WT)烟草叶绿体中过量表达CAT产生2个表达量不同的转基因株系(C1、C3)。用10ppm、20ppm和40ppm气体甲醛处理WT和转基因烟草,分析过量表达CAT的转基因烟草对甲醛的吸收效率和耐受性。结果表明,转基因烟草对气体甲醛的吸收量明显高于WT,且随着处理浓度的升高,转基因株系叶片的可溶性总糖、总蛋白质和总叶绿素含量都显著高于WT;转基因株系叶片氧化损伤指标H202、丙二醛(MDA)和羰基化蛋白(PC)的含量都显著低于野生型。转基因烟草(C1)的PM H+-ATPase和氢泵活性在40ppm处理后为WT的3倍和2.5倍,C1的气孔导度为WT的2.67倍。这些结果表明,在烟草中过量表达拟南芥CAT能降低甲醛进入烟草细胞引起的氧化损伤,提高烟草对甲醛的脱毒能力,增强烟草对甲醛的吸收和抗性。揭示气体甲醛胁迫时质膜H+-ATPase和氢泵活性影响叶片气孔的导度,这可能是转基因烟草甲醛吸收效率提高的原因之一。     

姜黄素对鼻咽癌细胞RECK基因甲基化以及MMP-9表达与活性的影响

目的探讨姜黄素对鼻咽癌细胞回复引导半胱氨酸丰富蛋白含kazal基元(RECK)基因甲基化以及基质金属蛋白酶9(MMP-9)表达的影响。方法体外培养鼻咽癌细胞系CNE-1,用1、10、30μmol/L姜黄素处理后,采用Western blot和实时定量PCR分别检测RECK、MMP-9蛋白和mRNA表达;高效液相色谱-电喷雾质谱检测RECK甲基化;MTT法检测CNE-1细胞的增殖。同时采用明胶酶谱实验观察姜黄素处理前后MMP-9酶活性变化。结果 CNE-1细胞未刺激时RECK表达水平较低,而经1~30μmol/L姜黄素处理后,能显著增强RECK蛋白和mRNA的表达。高效液相色谱-电喷雾质谱结果显示,30μmol/L姜黄素处理后,RECK启动子、全基因组以及细胞核内甲基化水平分别降低为(69.04±10.62)%、(61.13±7.08)%、2.80±1.32。同时,姜黄素能显著降低CNE-1细胞中MMP-9蛋白和mRNA表达以及MMP-9的酶活性。结论姜黄素可能通过能上调RECK基因表达,降低细胞内甲基化水平,从而抑制MMP-9的表达与活性而发挥对CNE-1细胞生长抑制作用。     

盐胁迫下甜菜M14品系BvM14-ATPaseF、BvM14-ATPaseH、BvM14-PsaD基因的表达分析

甜菜M14品系是由栽培甜菜和野生白花甜菜杂交后获得的带有野生白花甜菜第9号染色体的单体附加系,具有抗逆、无融合等优良特性。在前期工作中,对盐胁迫下叶片膜蛋白进行了定量蛋白质组学分析,与未处理对照相比,200、400mM盐胁迫下共获得50个差异蛋白质点,选择其中3个蛋白质点为研究对象,与实验室前期相同盐处理下获得的转录组数据库相匹配,获得基因cDNA全长,将此3个基因命名为BvM14-ATPaseF、BvM14-ATPaseH和BvM14-PsaD;进行在线功能预测;设计引物,对盐胁迫(0、200、400 mM)处理下此3个基因进行实时荧光定量分析,了解在盐胁迫下基因转录与蛋白水平上表达量的关系。结果表明,与未处理对照相比,200、400 mM盐浓度处理下BvM14-ATPaseF基因分别上调3.70与4.47倍,BvM14-ATPaseH基因在盐胁迫处理下分别上调0.85与1.36倍,而BvM14-PsaD基因随着盐浓度的增加却下调0.97与2.54倍,表明在盐胁迫下不同基因具有的功能不同,而导致转录水平与蛋白水平的表达量并不完全相同。     

参慈胶囊联合顺铂对A549/DDP肺腺癌组织MDR1、MRP1、LRP表达的影响

目的:探讨参慈胶囊对人肺腺癌A549/DDP裸鼠体内多药耐药相关基因的影响。方法:将50只C57BL/6小鼠接种人肺腺癌细胞A549/DDP细胞悬液建立实体瘤模型,随机分为对照组、参慈胶囊组、参慈胶囊+顺铂组、顺铂组,各10只。对照组予等量生理盐水,其余各组荷瘤小鼠均用药21 d,断颈处死取肿瘤组织,采用FQ-PCR技术检测人肺腺癌A549/DDP肺癌组织MDR1、MRP1、LRP m RNA的表达情况。结果:MDR1 m RNA、MRP1 m RNA、LRP1 m RNA在各组均有表达,各治疗组的MDR1m RNA、MRP1 m RNA、LRP1 m RNA均低于对照组,差异均有统计学意义(P<0.01);参慈胶囊+顺铂组的MDR1 m RNA、MRP1 m RNA、LRP1 m RNA的表达均明显低于参慈胶囊组和顺铂组,差异均有统计学意义(P<0.01)。结论:通过降低MDR1、MRP1、LRP多药耐药相关基因的表达,可能是参慈胶囊逆转人肺腺癌A549/DDP裸鼠体内多药耐药的作用机制之一。     

高中语文教学高效课堂策略探究

高效课堂是所有教师不懈的追求。在高中语文课堂教学中,如何追求教学效益的最大化,提高学生的语文素养是教师一直在探究的问题。随着新课程的实施,新的课程理念给课堂教学注入了生机,实现高效课堂已经变为现实。在高中语文课堂教学中,采用新课程提倡的探究式学习方式,调动了学生的学习积极性,学生在探究的过程中,掌握了知识,提高了能力,实现了课堂教学效率最大化。     

植物重金属胁迫耐受机制

重金属是一类会对植物产生毒害作用的污染物,植物在长期进化过程中演变出耐受重金属胁迫的相关机制。以植物重金属耐受性为基础,对近几年来国内外植物响应重金属胁迫的耐受机制研究作一简要综述。主要概述了重金属对植物的胁迫影响及植物抗氧化系统,脯氨酸、可溶性糖、可溶性蛋白等渗透调节物质和不同类型基因家族等方面对植物耐受重金属胁迫机制的研究进展。以期为提高植物耐重金属胁迫能力及研究植物修复重金属污染土壤的应用奠定一定的基础。     

Abiotic transformation of catechol and 1-naphthol in aqueous solution-influence of environmental factors

The abiotic transformation of catechol and 1-naphthol singly and in mixtures was tested in sterile Tris-HCl buffer with regard to several environmental factors including temperature (7 degrees C, 20 degrees C and 30 degrees C), lighting conditions, pH (between 7.0 and 8.5) and dissolved oxygen (at partial pressures of 0.0, 220, 2200, 11000 and 22000 Pa). Irrespective of lighting conditions. catechol autoxidation was confirmed in aerated medium with a rate independent of the presence of 1-naphthol but proportional to the dissolved oxygen concentration, to the pH (its half-disappearance occurred in 24h at pH 8.5) and, to a lesser extent, to the incubating temperature (at 20 degrees C, 20% disappeared in 10 days at pH 7.0). Under alkaline conditions, the reaction of the anionic form (catecholate) with an equimolar concentration of molecular oxygen (O2) led presumably to hydrogen peroxide anion (HO2-) and coloured polymerization products. When tested alone, 1-naphthol was not significantly influenced either by lighting conditions, incubating temperature or dissolved oxygen concentration. It was also found to be quite stable with respect to pH, with a 15-fold weaker transformation rate than for catechol at the highest pH used. When tested in a mixture with catechol, 1-naphthol was found to be involved in a new chemical oxidation reaction catalyzed by catecholate. The transformation of one mole of 1-naphthol consumes four moles of oxygen. In the presence of catechol, the stoichiometry of the 1-naphthol transformation, under the influence of oxygen, suggests the possible formation of 2,5,6,8-tetrahydroxy 1,4-naphthoquinone via Lawsone (2-hydroxy 1,4-naphthoquinone) and naphthopurpurine (2,5,8-trihydroxy 1,4-naphthoquinone) as hypothetic intermediates. This is the first report of the autoxidation of 1-naphthol, catalyzed by catechol, in aqueous solution, in the absence of UV irradiation.     

医教结合理念下特殊职业教育课程资源的开发与运用——以面点工艺专业为例

医教结合理念下,特殊职业教育课程资源开发需要聚焦专业技能教学和功能康复训练的双维度融合。基于医教结合理念,转换课程教学内容,采用教学与训练协作共进模式,并设计多元行动路径,以此重构课程结构体系。基于面点工艺专业,梳理专业教学内容,分析、归类核心操作技能,开发支持式手指操辅助资源;同时,结合具体课程内容设计教学实验方案,通过实践落实资源的有效运用。结果表明:专业性支持式课程资源干预技能教学与训练,可以提升技能掌握度,并在一定程度上促进机体功能康复。     

Abiotic methylation of mercury in the aquatic environment

Methylation of inorganic mercury in the aquatic environment has been considered to be largely the result of biological processes, primarily involving sulfate-reducing bacteria. However, these processes cannot account for all of the methylmercury that is formed naturally. A growing body of evidence suggests that chemical reactions represent another possible pathway for mercury methylation in the aquatic environment. In order to assess the abiotic contribution to mercury methylation in the water column, and specifically the conditions under which this contribution may be significant, the current state of knowledge about environmentally significant methylation reactions is reviewed. Results of our laboratory-based investigations of aqueous mercury reactions with some potential methyl donors, including MeCo(dmg)(2)(H2O), a simple model for methylcobalamin, various methyltin compounds and methyl iodide, are presented. In each reaction, the yield of methylmercury and the rate of methylation depend strongly on environmental factors such as pH, temperature, and the presence of complexing agents, especially chloride.     

不同绿化树种抗旱性、抗盐性及抗涝性比较

为了探讨不同树种间抗逆性的差异,以华北五角枫、紫薇、青檀、榔榆、木槿1年生扦插苗为试验材料,对其抗旱性、抗涝性和抗盐性进行比较,并用隶属函数法进行综合评价。结果表明:不同树种间抗逆性差异较大,供试材料抗性强弱依次为:紫薇>榔榆>木槿>华北五角枫>青檀。     

Tolerance of Antarctic soil fungi to hydrocarbons

Little is known about the effects of hydrocarbons and fuel oil on Antarctic filamentous fungi in the terrestrial Antarctic environment. Growth of fungi and bacteria from soils around Rothera Research Station (Adelaide Island, Antarctic Peninsula) was assessed in the presence of ten separate aromatic and aliphatic hydrocarbons [marine gas oil (MGO), dodecane, hexadecane, benzoic acid, p-hydroxybenzoic acid, toluene, phenol, biphenyl, naphthalene and m- and p-xylenes with ethylbenzene]. Aromatic hydrocarbons inhibited soil microbial growth more than aliphatic hydrocarbons. Soil microorganisms from a moss patch, where little previous impact or hydrocarbon contamination had occurred, were less tolerant of hydrocarbons than those from high impact sites. Fungal growth rates of Mollisia sp., Penicillium commune, Mortierella sp., Trichoderma koningii, Trichoderma sp. and Phoma herbarum were assessed in the presence of hydrocarbons. Generally, aromatic hydrocarbons inhibited or stopped hyphal extension, though growth rates increased with some aliphatic hydrocarbons. Hyphal dry weight measurements suggested that Mortierella sp. may be able to use dodecane as sole carbon and energy source. Hydrocarbon-degrading Antarctic fungi may have use in future hydrocarbon spill bioremediation.     

对冠心病心脏康复后护理的探索

冠心病(coronary artery disease,CHD)是一种在全世界范围内广泛发生的疾病,20世纪以来,人们生活水平不断提高的同时,体力锻炼活动的时间也在逐渐的减少,冠心病的发病率有逐年增加的趋势。相当一部分患者在经过冠状动脉介入术或搭桥术后得以存活,鉴于冠心病相关危险因素的不可逆性,术后复发率依然很高。因此,对于手术后恢复的冠心病患者进行心脏康复(cardiac rehabilitation,CR)就有很重要的现实意义。随着对疾病的深入研究,现代医学对冠心病的认识已经不是单纯的停留在治疗方面,更是需要满足一个高水平的健康状态和保证高质量的生存条件,因此,以运动为基础的冠心病术后心脏康复治疗逐渐成为一种较为理想的治疗方式。     

胃癌组织中TGFBR1的基因突变研究

目的揭示胃癌组织的转化生长因子-β受体1(TGFBR1)的突变位点,探索其在胃癌发生发展过程中的作用。方法将20例胃癌组织标本进行DNA提取,PCR扩增,应用Sanger双脱氧测序法进行TGFBR1全部外显子的基因测序,再对序列进行分析,找到TGFBR1的基因突变位点。结果在6例标本中得到了TGFBR1外显子9的7个基因突变位点(c.1470 G>A;c.1491 G>A;c.1493 G>A;c.1543 G>A;c.1624 G>A;c.1675 G>A;c.1684 G>A),均是第一次发现和报道。TGFBR1的基因突变与胃癌患者的年龄、性别、分化程度、淋巴结转移及分期均无关(P>0.05)。结论本实验发现7个未报道的TGFBR1基因突变位点,其中3个错义突变(c.1470G>A;c.1491 G>A;c.1493 G>A)可能是胃癌患者的致病原因之一,对揭示TGFBR1与胃癌的确切关系有重要意义。