百合花瓣衰老过程中的蛋白质变化研究

以5个百合品种为材料,对百合切花花瓣衰老过程中可溶性蛋白的变化进行了研究.结果表明,5个品种的百合切花都具有相同的蛋白质条带,如49.9 kDa、45 kDa、32.8 kDa、22.1 kDa;但品种问也有明显差异,如38.4 kDa是'黄色风暴'特有的;40 kDa为'铁炮百合'特有;'金百合'没有26.5 kDa的条带,但是相同的杂交品系之间蛋白条带的相似性要明显高于不同杂交品系;在百合花花瓣衰老过程中有的蛋白质的含量不断下降,而有的保持不变;在花瓣衰败期有新的蛋白条带出现,如'西伯利亚'、'黄色风暴'和'索邦'均出现58.3 kDa条带、'金百合'出现67 kDa的条带,这些条带可能与花瓣衰老相关,是衰老特异蛋白.     

超高产杂交稻剑叶衰老过程中的抗氧化性的变化

与对照种汕优63相比,超高产水稻组合培矮64S/E32的剑叶在生长后期具有更高的抗氧化酶(抗坏血酸过氧化物酶APX和谷胱甘肽还原酶GR)活性和小分子抗氧化剂(抗坏血酸Vc、总Vc、还原型谷胱甘肽GSH和β-胡萝卜素)含量,高的清除有机自由基DPPH·能力,更低的膜脂过氧化产物丙二醛含量。这表明培矮64S/E32剑叶在生长后期有强的抗氧化性,这种强抗氧化性与超高产水稻在结实后期剑叶中较慢的叶绿素和蛋白质降解速度相一致。     

大鼠海马CA1区神经元在衰老过程中的形态学变化

对不同年龄组雄性ＳＤ大鼠海马ＣＡ１区锥体层神经元分别做光学和电镜观察与测定,结果表明ＣＡ１区锥体层单位面积内神经元数目随增龄下降达３３％（Ｐ＜０．００１）,同时伴有锥体层厚度的增加（Ｐ＜０．００１）;ＣＡ１区部分锥体神经元细胞器与胞突在老化过程中出现一系列形态学变化。本文对上述结果及其意义进行了讨论。     

小鼠增龄过程中耳蜗MeCP2的变化

在对不同月龄BALB/c小鼠听功能和耳蜗形态学研究的基础上,应用免疫组化技术,检测不同月龄组(3,6,12,18月龄)小鼠耳蜗组织中MeCP2的表达与分布情况,初步探讨其在听觉老化中的作用.结果显示,MeCP2蛋白在BALB/c小鼠耳蜗中有表达,主要为细胞核着色,并随月龄增长,小鼠耳蜗染色阳性程度变弱,阳性细胞比例减少...     

天山中部天然云杉林森林生态系统降水过程中的水质变化

通过对天山中部天山云杉(Picea schrenkiana var.tianschanica (Rupr.)Chen et Fu)不同郁闭度、林龄天然林区内,降水在转化过程中各环节(包括大气降水、穿透水、地表径流、地下渗水)的水质变化规律,以及森林生态系统不同层次对水质的影响对比分析。结果表明:(1)天山云杉林生态系统对降雨的水质影响,随郁闭度和林龄的增加而增强。在林龄相同的条件下,表现为:0.20.40.60.8;在郁闭度为0.8的条件下,表现为:幼龄林中龄林成熟林近熟林;(2)大气降水透过林冠层后,水中的养分含量显著增高,表现为溶解氧含量减小,氨氮、COD、BOD、总磷、钾含量增加;(3)穿透水转化为地表径流,水中的溶解氧浓度进一步降低,COD、BOD、总磷、钾的含量升高,氨氮浓度降低;(4)总地下渗水的各项水质指标均明显优于大气降水,土壤层是森林生态系统净化水质的关键层。(5)通过对各集水区域水质指标定量化综合评价,天山云杉林生态系统内的水质质量表现为:7月份9月份8月份;(6)利用主成分分析方法(PAC)构建的水质综合评价多元线性模型,具有很强代表性,能很好地用于水质的等级评价。     

马齿苋多糖对衰老小鼠肠道微生态调节作用的研究

目的探讨中药马齿苋多糖对衰老小鼠微生态调节作用。方法皮下注射D-半乳糖建立衰老小鼠模型,用马齿苋多糖进行治疗,同时设正常对照组、阳性对照组和阴性对照组,用药30d后处死小鼠,进行肠道微生态指标检测。结果用D-半乳糖造模以后,小鼠肠道双歧杆菌及乳酸杆菌数量降低（P〈0．05）,而肠杆菌及肠球菌数量增加说明模型建立,血内毒素含量也升高（P〈0．05）。用马齿苋治疗后,益生菌数量升高而肠杆菌和肠球菌数量减少,血内毒素含量也降低（P〈0．05）。结论马齿苋多糖对衰老小鼠的肠道菌群和血内毒素具有调节作用。     

花衰老过程中的生理生化变化及对花衰老的调节(综述)

本文概述花衰老过程中的多种生理生化变化以及各种影响因素的调节作用。     

潘氏细胞在昆明小鼠弓形虫病发病过程中的变化

每只昆明小鼠灌胃1×104个弓形虫卵囊,分别在灌胃后1,3,5,6 DAI(days after inoculation),采用HE方法和免疫组织化学方法对小鼠回肠潘氏细胞的变化以及弓形虫在回肠的分布和数量进行研究,探讨潘氏细胞(paneth cells,PCs)在小鼠弓形虫病感染期间的变化。结果发现,回肠隐窝总数、含PCs的隐窝数、PCs总数及颗粒总数呈先增加后迅速减少至消失的趋势,回肠后段表现明显,6 DAI各参数与对照组比较差异显著(P0.05)。弓形虫在回肠中的分布面积呈增大趋势,6 DAI与1 DAI、3 DAI相比差异显著(P0.05)。该研究结果表明,弓形虫卵囊感染昆明小鼠可减少回肠潘氏细胞及其分泌颗粒的数量,为以小肠潘氏细胞为基础的弓形虫病的防治提供了实验依据。     

An Animal Model of Type A Cystinuria Due to Spontaneous Mutation in 129S2/SvPasCrl Mice

Cystinuria is an autosomal recessive disease caused by the mutation of either SLC3A1 gene encoding for rBAT (type A cystinuria) or SLC7A9 gene encoding for b^0,+AT (type B cystinuria). Here, we evidenced in a commonly used congenic 129S2/SvPasCrl mouse substrain a dramatically high frequency of kidney stones that were similar to those of patients with cystinuria. Most of 129S2/SvPasCrl exhibited pathognomonic cystine crystals in urine and an aminoaciduria profile similar to that of patients with cystinuria. In addition, we observed a heterogeneous inflammatory infiltrate and cystine tubular casts in the kidney of cystinuric mice. As compared to another classical mouse strain, C57BL/6J mice, 129S2/SvPasCrl mice had an increased mortality associated with bilateral obstructive hydronephrosis. In 129S2/SvPasCrl mice, the heavy subunit rBAT of the tetrameric transporter of dibasic amino acids was absent in proximal tubules and we identified a single pathogenic mutation in a highly conserved region of the Slc3a1 gene. This novel mouse model mimicking human disease would allow us further pathophysiological studies and may be useful to analyse the crystal/tissue interactions in cystinuria.     

Rheumatoid factor production in 129/Sv mice: involvement of an intestinal infectious agent

High titers of IgG2a-specific rheumatoid factors (RF) are frequently observed in colonies of 129/Sv mice. The involvement of a transmissible agent in this phenomenon was shown by the following findings: (i) cesarean-derived and isolator-reared offsprings of RF-positive dams were free of RF, ii) a single intragastric inoculation with intestinal fluid from RF-positive donors elicited chronic RF production in RF-negative recipients, and iii) intestinal fluid collected from these primary recipients induced a comparable RF response in a second set of animals. The nature of this RF-inducing agent, however, remained elusive. Although its ability to pass through filters that efficiently retained bacteria could be unequivocally established, systematic serological analysis failed to detect any significant correlation between RF production and antibody responses to common mouse viruses or Mycoplasma. Moreover, all attempts to identify the RF-inducing agent by electron microscopy or to grow it in nude or newborn mice, as well as in cell cultures, remained unsuccessful.     

PM2.5暴露荷瘤裸鼠后肠道菌群组成的改变

目的 了解暴露PM2.5后的Bac荷瘤裸鼠肠道菌群组成的变化。方法 采用A549细胞对30只Bac裸鼠进行肺内注射,饲养1周适应环境,第2周开始进行暴露染尘与对照暴露生理盐水组实验,共暴露1、4、8周。采用口鼻暴露仓进行小鼠染尘与生理盐水暴露操作,每周暴露6 d,每天2 h,建立大气污染暴露荷瘤裸鼠模型,5只未做处理的Bac荷瘤裸鼠作为空白对照组。采集裸鼠晨起新鲜粪便样品,抽提其中微生物总基因组DNA,采用Ⅱ代基因测序技术对粪便样品进行16S高变区扩增测序,划分可操作分类单元（operational taxonomic unit,OTU）,使用I-Sanger分析平台对所有OTU进行物种注释与评估、物种组成分析、样本比较分析等,运用R Studio软件对数据进行统计学分析。结果 厚壁菌门和拟杆菌门在PM2.5暴露组、生理盐水对照组和空白对照组均为最优势菌门。PM2.5暴露组与生理盐水对照组及空白对照组相比厚壁菌门减少,拟杆菌门增加。结论 PM2.5暴露减少Bac荷瘤裸鼠肠道菌群丰度,破坏肠道菌群平衡,在一定程度上可抑制有益菌的繁殖,并使致病菌数量增加。     

小鼠肠道优势菌群失衡肠黏液sIgA、黏液素的变化

目的研究肠道菌群失衡对小鼠肠黏膜机械屏障的影响,探讨优势菌群与肠道黏膜屏障的相互作用机制。方法利用ELISA法检测肠黏膜sIgA含量变化,RT-PCR技术及免疫组化法检测肠黏膜上皮细胞Mucin2、Mucin3和防御素mRNA转录产物的变化。结果菌群失衡小鼠小肠段肠黏膜sIgA水平下降,重度菌群失衡组与正常组比较下降显著（P〈0.05）,与轻度菌群失衡组相比下降明显。菌群失衡小鼠上皮细胞中的Mucin2、Mucin3和防御素mRNA转录产物与正常小鼠相比明显增高,在杯状细胞胞浆内Mucin2蛋白阳性表达增强,且重度菌群失衡组与轻度菌群失衡组小鼠比较,Mucin2、Mucin3和防御素增高明显。结论菌群失衡可导致肠黏膜sIgA分泌量随菌群失衡程度呈下降趋势,同时引起黏液层中黏液素和防御素分泌量增加。     

Behavioral alterations induced by repeated testing in C57BL/6J and 129S2/Sv mice: implications for phenotyping screens

The C57BL/6JOlaHsd and 129S2/SvHsd mice were tested in a battery designed for behavioral phenotyping of genetically modified mice. The study was performed in order to reveal the effect of training history on the behavior by comparison with the experimentally naïve mice in the same tests. Significant strain differences were obtained in all experiments. Previous handling and testing reduced exploratory activity and emotionality significantly in the mice. The coordination ability was better and nociceptive sensitivity was increased in the trained mice. The contextual fear was reduced whereas the cued fear was enhanced in the experienced mice. The training history did not alter initial learning in the water maze. However, after reversal learning the naïve mice displayed significant preference for both old and new platform locations, whereas the battery animals did not exhibit preference to the old location. The experienced mice appeared to be less active in the forced swimming test and exhibited decreased conditioned taste aversion. The influence of test history was strain-dependent in certain cases. Therefore, the experience has substantial consequences on the behavior, mainly by reducing exploratory activity, and the previous experience of the animals has always to be considered in the analysis of genetically modified mice.     

Impaired substrate utilization in mitochondria from strain 129 dystrophic mice

Mitochondria from skeletal muscle, heart and liver of strain 129/ReJ-dy dystrophic mice and their littermate controls were characterized with respect to their respiratory and phosphorylating activities. Skeletal muscle mitochondria from dystrophic mice showed significantly lower state 3 respiratory rates than controls with both pyruvate + malate and succinate as substrates (P < 0.01). ADP/O and Ca²⁺/O ratios were found to be normal. A decreased rate of NADH oxidation (0.01 <P < 0.05) by sonicated mitochondrial suspensions from dystrophic mice was also seen. High respiratory rates with ascorbate + phenazine methosulfate as substrates indicated that cytochrome oxidase was not rate limiting in the oxidation of either pyruvate + malate or succinate. Skeletal muscle mitochondria from dystrophic mice showed no deficiency in any of the cytochromes or coenzyme Q. Mg²⁺-stimulated ATPase activity was higher in dystrophic muscle mitochondria than in controls, but basal and oligomycin-insensitive activities were virtually identical to those of controls. A significant reduction in the intramitochondrial NAD⁺ content (0.01 <P < 0.02) was seen in dystrophic skeletal muscle as compared to controls. Heart mitochondria from dystrophic mice showed similar, though less extensive abnormalities while liver mitochondria were essentially normal. We concluded from these results that skeletal muscle mitochondria from strain 129 dystrophic mice possess impairments in substrate utilization which may result from (1) an abnormality in the transfer of electrons on the substrate side of coenzyme Q in the case of succinate oxidation; (2) a defect on the path of electron flow from NADH to cytochrome c, and (3) a deficiency of NAD⁺ in the case of NAD⁺-linked substrates.     

旋毛虫感染小鼠肠道菌群变化的研究

目的通过观察黑龙江株旋毛虫感染小鼠肠道分泌物中分泌型免疫球蛋白A、肠道菌群的变化,探讨感染小鼠肠道菌群的变化。方法分别于小鼠感染黑龙江株旋毛虫后7、14、21、28和35d,观察模型组及对照组小鼠肠道分泌物中的分泌型免疫球蛋白A、肠道双歧杆菌、乳酸杆菌、肠杆菌、肠球菌的菌群变化。sIgA采用放射免疫法检测。结果模型组sIgA分泌水平在感染后14d达高峰,随后缓慢下降但始终保持高水平（P〈0．01）。模型组肠道双歧杆菌的数量在感染后7d略低于对照组（P〈0．05）,第14天降至最低水平,随后逐渐升高,至感染后35d恢复正常水平。乳酸杆菌的数量在感染后7d略低于对照组,第14天降至最低水平,随后逐渐增加（P〈0．05）。肠杆菌的数量在感染后7d略高于对照组,感染后14d明显高于对照组,随后始终保持下降趋势（P〈0．05）。肠球菌在感染后7d略高于对照组（P〈0．05）,在14d明显高于对照组,随后缓慢下降,至感染后35d恢复正常水平。结论旋毛虫感染小鼠sIga的分泌在肠道免疫中发挥重要作用,同时也影响肠道菌群;肠道菌群的变化可能与旋毛虫感染小鼠免疫系统中sIgA的分泌有关。