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131.
To obtain microRNA (miRNA) profile and clarify their biological function in tumorigenic Sca‐1+CD34+ cells during carcinogenesis of lung adenocarcinoma. After intranasal infection with recombinant Adeno‐Cre viruses (AdV‐Cre), lung adenocarcinoma was identified pathologically in Lox‐stop‐lox Kras (LSL‐Kras) G12D mice. Sca‐1+CD34+ cells were sorted by flow cytometry and tested for tumor‐initiating ability, self‐renewal and tumorigenicity. MiRNA profiles were obtained using microarray and further confirmed by real‐time RT‐PCR (qRT‐PCR). MiRNA functions were predicted bioinformatically, and miR‐294 function was verified to explore its role in tumor migration and invasion. Lung adenocarcinoma was induced in LSL‐Kras G12D mice within 30 days. In vivo, the tumorigenicity of Sca‐1+CD34+ cells was 25 times stronger than Sca‐1?CD34? cells. During tumorigenesis of lung adenocarcinoma, the expression of 145 miRNAs in Sca‐1+CD34+ cells increased and 72 miRNAs decreased (P < 0.01). Four successively up‐regulated miRNAs (miR‐15a*, miR‐203, miR‐294 and miR‐295*) and three successively down‐regulated ones (miR‐19b, miR‐483 and miR‐615–5p) were identified. Among them, miR‐294 could constitutively bind to 3'‐UTR of matrix metalloproteinase 3 (MMP3), and down‐regulate MMP3 protein expression. MiR‐294 also significantly inhibited migration and invasion of Lewis lung cancer cells. MiRNAs are characteristically expressed in tumor‐initiating Sca‐1+CD34+ cells of lung adenocarcinoma, and may play important roles during the carcinogenesis of lung adenocarcinoma. J. Cell. Biochem. 116: 458–466, 2015. © 2014 The Authors. Journal of Cellular Biochemistry published by Wiley Periodicals, Inc.
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132.
细菌性阴道病(bacterial vaginosis,BV)可以通过破坏机体的免疫调节作用使HPV在宫颈组织中持续感染,导致宫颈癌前上皮内瘤变(cervical intraepithelial neoplasia,CIN)和宫颈癌。同时对BV的诊断可以作为预测CIN发展和宫颈癌发生的生物预测方法,对BV的诊断除了传统的Amsel标准和Nugent评分外,还可通过16S rRNA高通量测序、探针检测和实时PCR等新的分子生物学方法来精确诊断。应用益生菌治疗菌群失调的同时可以预防CIN的发展和宫颈癌的发生,因此通过改善菌群失调来调节机体对HPV病毒的免疫反应可能成为治疗CIN和宫颈癌的新方法。  相似文献   
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134.
Pharmacological treatment is a therapeutic approach to improving nerve regeneration and functional recovery after peripheral nerve crush injury. The objective of the present study was to investigate the effects of the polypeptides isolated from Achyranthes bidentata Blume (abbreviated as ABPP) on rat sciatic crush injury and to test the possible involvement of neurotrophic factors. After surgical crush injury, rats received daily intraperitoneal injection of 0.2 ml saline containing 2 mg ABPP, 1 μg nerve growth factor (NGF) or no additive. The results from walking track analysis, electrophysiological assessment and histological evaluation indicated that the repair outcomes by ABPP treatment were close to those by NGF treatment, but better than those by treatment with saline alone. The quantitative real-time RT-PCR was used to monitor the mRNA expression of growth associated protein in the crush nerves and the mRNA expression of NGF, brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), tyrosine kinase (Trk)A and TrkB in the dorsal root ganglia (DRGs) at L4–L6. The mRNA expression of these genes in the crush nerve sample and DRGs sample was higher after treatment with ABPP or NGF than after treatment with saline alone. Our findings suggest that ABPP might protect peripheral nerve against crush injury through stimulating release of neurotrophic factors and the other cytokines.  相似文献   
135.
通过高效液相色谱(HPLC)、高分辨率质谱(HRMS)和~H和~(13)C核磁共振(NMR)证明1株球毛壳菌Chaetomiumglobosum NKl02产生的杀根结线虫(Meloidogyne spp.)成分为球毛壳甲素(Chaetoglobosin A)。C.globosum NK102能够利用微晶纤维素、杨树叶和木屑合成ChA。在12 d发酵液中,3种培养基获得的ChA产量由高到低的顺序为PDA、杨树叶、微晶纤维素和木屑,产量分别为26.49、9.38、4.47和0.47 mg/L。通过在微晶纤维素培养基中添加表观遗传沉默抑制药物表明:100μmol/L 5′-AZA的添加使得ChA的产量提高至原来的3.6倍,100μmol/L SAHA将ChA的产量提高到原来的2.4倍,DMSO使得ChA的产量提高到原来的1.7倍。这个结果预示ChA的合成的某些基因受到表观遗传调控。  相似文献   
136.
In the natural environment, organisms are exposed to large variations in physical conditions. Quantifying such physiological responses is, however, often performed in laboratory acclimation studies, in which usually only a single factor is varied. In contrast, field acclimatization may expose organisms to concurrent changes in several environmental variables. The interactions of these factors may have strong effects on organismal function. In particular, rare events that occur stochastically and have relatively short duration may have strong effects. The present experiments studied levels of expression of several genes associated with cellular stress and metabolic regulation in a field population of limpet Cellana toreuma that encountered a wide range of temperatures plus periodic rain events. Physiological responses to these variable conditions were quantified by measuring levels of mRNA of genes encoding heat‐shock proteins (Hsps) and metabolic sensors (AMPKs and Sirtuin 1). Our results reveal high ratios of individuals in upregulation group of stress‐related gene expression at high temperature and rainy days, indicating the occurrence of stress from both prevailing high summer temperatures and occasional rainfall during periods of emersion. At high temperature, stress due to exposure to rainfall may be more challenging than heat stress alone. The highly variable physiological performances of limpets in their natural habitats indicate the possible differences in capability for physiological regulation among individuals. Our results emphasize the importance of studies of field acclimatization in unravelling the effects of environmental change on organisms, notably in the context of multiple changes in abiotic factors that are accompanying global change.  相似文献   
137.
抗除草剂杂交籼稻亲本的配合力分析   总被引:2,自引:0,他引:2  
本试验以6份新育成的抗除草剂籼型恢复系为父本,5份生产上广泛应用的不育系为母本,采用不完全双列杂交设计配制了30份杂交组合,对其苗期除草剂抗性和主要农艺性状配合力进行了分析。除草剂抗性鉴定表明,亲本恢复系及三系杂交组合抗性接近完全,两系杂交组合抗性达90%以上。配合力分析表明,不育系除单株有效穗数外其他农艺性状的一般配合力均达到极显著差异;恢复系间一般配合力在所有性状中均达到显著或极显著差异;杂交组合间特殊配合力方差仅在单株产量、结实率、播始历期和千粒重4个性状中达到显著或极显著差异。不育系中,金科1A在单株产量、结实率等7个性状上的一般配合力均为最高,但其特殊配合力方差最小;广占63-4S在千粒重性状上具有最高的一般配合力、最大的特殊配合力方差,在播始历期上具有最高的一般配合力负效应;C815S在株高上的一般配合力负效应最大,同时特殊配合力方差较高。恢复系中,华抗恢101在单株有效穗数上具有最高的一般配合力和特殊配合力方差;华抗恢104在穗长上具有最高的一般配合力,在播始历期上具有最高的一般配合力负效应;华抗恢105在单株产量、结实率等性状上具有最高的一般配合力,在株高上具有最高的一般配合力负效应;华抗恢106在千粒重性状上具有最高的一般配合力和特殊配合力效应方差。利用抗除草剂恢复系配制杂交组合,不仅可以改良其除草剂抗性,也可以通过广泛测配,选择一般配合力强、特殊配合力方差大的亲本配组育成强优势组合。  相似文献   
138.
应用电镜技术对蕨类植物绵马鳞毛蕨(RYOPTERIS CRASSIRHIZOMA Nakai)精母细胞和游动精子的超微结构特征进行了研究。精母细胞为多边形,细胞质内含有丰富的线粒体、质体、内质网、高尔基体等常见的细胞器.在细胞质中还可见到一些同心圆膜状结构,位于质膜的附近或精母细胞的角偶。同心圆膜状结构由双层膜环绕构成,外被l层单位膜。精母细胞与精子器的璧细胞之间形成了分离腔。在精母细胞质膜外形成了嗜锇层,这些结构的形成说明精母细胞已经开始与雄配子体逐渐分离,进入独立发育的阶段。尽管精母细胞之间也有嗜锇层的形成,但嗜锇层是不连续的,其上有一些空隙,精母细胞之间可通过空隙进行物质和信息的交流。成熟的精子细胞外被l层透明的薄膜,里面为游动精子。螺旋状。由环状细胞器环绕3~4圈构成.这些环状细胞器包括多层结卡构、微管带、巨大线粒体、鞭毛带和1个长形浓缩的细胞核。游动精子的后端为一些泡囊化的细胞质.其中包括一些残存的线粒体、造粉质体及大的囊泡等。当成熟的精子细胞排出精子器后。其内的游动精子挣脱透明质膜的束缚,摆脱后端的囊泡,成为1条游动精子。本文还对绵马鳞毛蕨和其它蕨类植物精子的超微结构特征进行了比较。  相似文献   
139.
目的分析微小膜壳绦虫感染人体所致病变特点及临床表现,阐明微小膜壳绦虫病发病的流行病学依据。方法对大连地区1例微小膜壳绦虫病患者的发病原因及临床表现,结合文献报道对其流行病学进行探讨分析。结果人体感染少数微小膜壳绦虫时,一般没有明显的症状。感染严重时,尤其在儿童可表现消化系统与神经系统的症状,注意饮食卫生和加强鼠害防制是控制该病感染和传播的重要措施。  相似文献   
140.
野生来源TW小鼠近交系培育及其生物学特性的研究   总被引:3,自引:3,他引:0  
目的 培育中国特有TW (TianjinWild)野生小鼠来源的实验近交小鼠品系 ,筛选其重要的生物学特征 ,丰富现有实验动物基因库。方法 严格按照国际培育近交系动物标准 ,即每代繁育的雌雄小鼠严格按照同胎雌雄 (兄妹 )进行交配。结果 经过 1 2年的精心培育 ,培育TW小鼠至F2 2代 ,其他 1 5地野生小鼠品系均因故中断。结论 该项研究将为丰富国际现有实验小鼠基因库资源 ,建立抗肺肿瘤特性实验小鼠模型动物奠定坚实基础。  相似文献   
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