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991.
Dan Li William Yang Yifan Zhang Jack Y Yang Renchu Guan Dong Xu Mary Qu Yang 《BMC medical genomics》2018,11(5):106
Background
Non-small cell lung cancer (NSCLC) represents more than about 80% of the lung cancer. The early stages of NSCLC can be treated with complete resection with a good prognosis. However, most cases are detected at late stage of the disease. The average survival rate of the patients with invasive lung cancer is only about 4%. Adenocarcinoma in situ (AIS) is an intermediate subtype of lung adenocarcinoma that exhibits early stage growth patterns but can develop into invasion.Methods
In this study, we used RNA-seq data from normal, AIS, and invasive lung cancer tissues to identify a gene module that represents the distinguishing characteristics of AIS as AIS-specific genes. Two differential expression analysis algorithms were employed to identify the AIS-specific genes. Then, the subset of the best performed AIS-specific genes for the early lung cancer prediction were selected by random forest. Finally, the performances of the early lung cancer prediction were assessed using random forest, support vector machine (SVM) and artificial neural networks (ANNs) on four independent early lung cancer datasets including one tumor-educated blood platelets (TEPs) dataset.Results
Based on the differential expression analysis, 107 AIS-specific genes that consisted of 93 protein-coding genes and 14 long non-coding RNAs (lncRNAs) were identified. The significant functions associated with these genes include angiogenesis and ECM-receptor interaction, which are highly related to cancer development and contribute to the smoking-free lung cancers. Moreover, 12 of the AIS-specific lncRNAs are involved in lung cancer progression by potentially regulating the ECM-receptor interaction pathway. The feature selection by random forest identified 20 of the AIS-specific genes as early stage lung cancer signatures using the dataset obtained from The Cancer Genome Atlas (TCGA) lung adenocarcinoma samples. Of the 20 signatures, two were lncRNAs, BLACAT1 and CTD-2527I21.15 which have been reported to be associated with bladder cancer, colorectal cancer and breast cancer. In blind classification for three independent tissue sample datasets, these signature genes consistently yielded about 98% accuracy for distinguishing early stage lung cancer from normal cases. However, the prediction accuracy for the blood platelets samples was only 64.35% (sensitivity 78.1%, specificity 50.59%, and AUROC 0.747).Conclusions
The comparison of AIS with normal and invasive tumor revealed diseases-specific genes and offered new insights into the mechanism underlying AIS progression into an invasive tumor. These genes can also serve as the signatures for early diagnosis of lung cancer with high accuracy. The expression profile of gene signatures identified from tissue cancer samples yielded remarkable early cancer prediction for tissues samples, however, relatively lower accuracy for boold platelets samples.992.
壳聚糖对镉胁迫下玉米幼苗叶片AsA-GSH循环的调控效应 总被引:2,自引:0,他引:2
以玉米(Zea mays L.)品种‘郑单958’为实验材料,分析外施壳聚糖对镉胁迫下玉米幼苗生物量、叶片镉含量、叶片超氧阴离子(O2·-)产生速率和过氧化氢(H2O2)的含量,以及抗坏血酸-谷胱甘肽(AsA-GSH)循环中抗氧化酶的活性及抗氧化物含量的影响。结果显示,随着镉胁迫时间的延长,玉米幼苗发生氧化胁迫,叶片抗氧化酶(APX、GR、DHAR、MDHAR)活性和抗氧化物(AsA、GSH)的含量降低,镉积累过量会抑制玉米幼苗的生长。施加壳聚糖可以降低镉胁迫下玉米幼苗叶片O2·-的产生速率和H2O2含量,提高上述抗氧化酶活性和抗氧化物的含量,促进AsA和GSH的再生,维持细胞的氧化还原状态,促进玉米幼苗的生长。研究结果表明壳聚糖处理后玉米幼苗保持了较高的AsA-GSH循环运作效率,提高了抗氧化能力,可有效缓解镉胁迫对玉米幼苗生长的抑制。 相似文献
993.
本文报导国人睾丸、附睾和输精管的NSE,AChE,ChE,ALP,ACP,5'-Nase,G-6-Pase,β-GA,β-GR,AP-M,ATPase和TPPase水解酶的组织化学活性、结果显示:睾丸曲细精管的ALP,5'-Nase和ATPase;睾丸间质细胞的NSE,ALP,ATPase和ACP;睾丸间质中的NSE,ALP和AT-Pasc;睾丸输出小管和附睾管上皮的NSE,ALP,ACP,5’-Nase,β-GA,β-GR,ATPase和Tppase;附睾头部间质中的NSE,AChE,ALP,和ATPase;输精管上皮细胞的ATPase的酶活性均呈强阳性或极强阳性。说明人类睾丸、附睾和输精管含有丰富的水解酶,尤其是附睾头部的输出小管、附睾管和头质均含有种类多活性高的水解酶,在精子的功能成熟上起了重要的作用,提示其可能作为生育与不育诊治中的重要指标。 相似文献
994.
本文从数学角度分析和研究了螺旋对称病毒衣壳参数、整理出衣壳参数20多个,对每一个参数的概念、含义等给予了明确的认定。提示了参数间的关系,推导出了一些计算参数值的公式。 相似文献
995.
Whereas protein disulfide isomerase (PDI) and prolyl isomerase (PPI) are considered as efficient protein folding catalysts, very few large scale processes use them because of economical and technical limitations. PDI and PPI were successfully immobilized on cross-linked agarose beads. PDI inactivation during coupling reaction was overcome by oxidizing active site thiols with dimethylsulfoxide and led to a 64% active enzyme. Alternatively, PPI and PDI biotinylation resulted in 100% and 55-66% active enzymes respectively. The use of these modified catalysts suppresses post-refolding purification and enables the design of biochemical reactors. Several other possible applications are also discussed. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 645-649, 1997. 相似文献
996.
对41例健康儿童和17例反复呼吸道感染患儿(复咸儿)的外周血淋巴细胞ADA活性进行了检测.两例ADA活性明显低下的复感儿的外周血T淋巴细胞被选作实验样品,经体外培养后,采用lipofectin介导的的方法导入外源性ADA基因.结果表明:体外培养的两例复感儿淋巴细胞中ADA活性较基因转移前升高;细胞免疫学特性也在一定程度上获得改善 相似文献
997.
998.
999.
Bao-He Qu Elizabeth Strickland Philip J. Thomas 《Journal of bioenergetics and biomembranes》1997,29(5):483-490
Cystic fibrosis (CF) is caused by mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator, CFTR. Previously we demonstrated that the common F508 mutation in the first nucleotide binding domain (NBD1) alters the ability of the domain to fold into a functional three-dimensional structure, providing a molecular explanation for the observation that the mutant CFTR is retained in the endoplasmic reticulum and does not traffic to the apical membrane of affected epithelial cells. Notably, when conditions are altered to promote folding of the mutant protein, it can assume a functional conformation. Correcting the folding defect may have therapeutic benefit for the treatment of cystic fibrosis. Here we summarize these results and discuss the implications in vitro folding studies have for understanding the pathobiology of CF. 相似文献
1000.
Ying Qu Lieve Moons Frans Vandesande 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,704(1-2)
An isocratic liquid chromatographic method with electrochemical detection for the determination of
-3,4-dihydroxyphenylalanine, dopamine, norepinephrine, epinephrine, serotonin, and their major metabolites, 3,4-dihydroxyphenylacetic acid, 4-hydroxy-3-methoxyphenylacetic acid and 5-hydroxyindole-3-acetic acid in chicken brain tissue is described. Chickens were killed at different ages, the brains were quickly frozen and 300-μm cryostat sections were made. From these sections, two to six tissue micropunches (1 mm in diameter) were punched out from 20 different areas of the hypothalamus and homogenated in 100 μl 0.1 M perchloric acid which included 0.01% cysteine as antioxidant. Fifty-μl supernatants were injected directly onto the LC system, separated on a 3-μm Phase II ODS column (100×3.2 mm I.D.) and detected by an electrochemical detector at a potential of +0.75 V. Standard curves, recoveries, analytical precision and detection limits were investigated for each monoamine neurotransmitter and its metabolites. The method was applied to study the influence of food restriction on the concentration of monoamine neurotransmitters in different brain areas, known to be involved in feeding and reproductive behaviour of female broiler chickens. Over 1000 micropunched tissue samples from ad libitum fed and food-restricted female broiler chickens were analyzed. Our results provide a possible role for catecholamines and indolamines in the altered feeding and reproductive behaviour of the broiler chicken. 相似文献
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