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931.
Defence reactions occurring in resistant (cv. Gankezaomi) and susceptible (cv. Ganmibao) muskmelon leaves were investigated after inoculating with Colletotrichum lagenarium. Lesion restriction in resistant cultivars was associated with the accumulation of hydrogen peroxide (H2O2). The activity of antioxidants catalase (CAT) and peroxidase (POD) significantly increased in both cultivars after inoculation, while levels of both CAT and POD activity were significantly higher in the resistant cultivar. Ascorbate peroxidase (APX) increased in both cultivars after inoculation, and level of APX activity was significantly higher in the resistant cultivar. Glutathione reductase (GR) activity significantly increased in both cultivars following inoculation, but was higher in the resistant cultivar, resulting in higher levels of ascorbic acid (AsA) and reduced glutathione (GSH). Phenylalanine ammonia lyase (PAL) significantly increased in inoculated leaves of both cultivars, resulting in higher levels of total phenolic compounds and flavonoids. The pathogenesis‐related proteins chitinase (CHT) and β‐1, 3‐glucanase (GLU) significantly increased following inoculation with higher activity in the resistant cultivar. These findings show that resistance of muskmelon plants against C. lagenarium is associated with the rapid accumulation of H2O2, resulting in altered cellular redox status, accumulation of pathogenesis‐related proteins, activation of phenylpropanoid pathway to accumulation of phenolic compounds and flavonoids. 相似文献
932.
Ge Qian 《The International Journal of Life Cycle Assessment》2014,19(7):1462-1467
Purpose
This paper aims to sort the literatures on life cycle assessments (LCA) by their respective importance through citation and co-citation analysis and to further discuss the strengths and weaknesses of these kinds of scientometric methods in the case of LCA research.Methods
CiteSpace II was used to generate document co-citation networks based on 3,824 articles retrieved from the ISI Web of Science database on this topic.Results
Table 1 provides the top 50 highest cited documents in the LCA field. Here, we use two indicators, i.e., citation frequency in citation analysis and betweenness centrality metric in co-citation analysis, to measure the importance of these LCA literatures.Conclusions
Citation and co-citation analysis are useful for environmental scientists and engineers to get a better understanding of the inner structure of LCA research. However, like all other research methods, this kind of analysis has some limitations. On the one hand, Scientometric studies and related software are very dependent on ISI Web of Science database, but considering the ISI Web of Science only began to track the LCA field fairly recently, the Scopus database would probably give a fuller picture. On the other hand, since the essence of scientometrics analysis is outsiders commenting insiders, so with only citation and co-citation analysis, to our understanding of the past, present, and future of LCA field, is insufficient. 相似文献933.
934.
Li-Chen Ge Zhuo-Jia Chen Hao Liu Kun-Shui Zhang Qiao Su Xiang-Yu Ma Hong-Bin Huang Zhen-Dong Zhao Yu-Ye Wang John P. Giesy Jun Du Hong-Sheng Wang 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Biphasic effects on cell proliferation of bisphenol A (BPA) can occur at lesser or greater exposures. Sertoli cells play a pivotal role in supporting proliferation and differentiation of germ cells. The mechanisms responsible for inverse effects of great and low concentrations of BPA on Sertoli cell proliferation need further study.Methods
We utilized proteomic study to indentify the protein expression changes of Sertoli TM4 cells treated with 10− 8 M and 10− 5 M BPA. The further mechanisms related to mitochondria, energy metabolism and oxidative stress were investigated by qRT-PCR and Western-blotting analysis.Results
Proteomic studies identified 36 proteins and two major clusters of proteins including energy metabolism and oxidative stress expressed with opposite changes in Sertoli cells treated with 10− 8 M and 10− 5 M BPA, respectively, for 24 h. Exposure to 10− 5 M BPA resulted in greater oxidative stress and then inhibited cell proliferation, while ROS scavenger NAC effectively blocked these effects. Exposure to 10− 8 M BPA caused higher intercellular ATP, greater activities of mitochondria, and resulted in significant proliferation of TM4 cells, while oligomycin A, an inhibitor of ATP synthase, abolished these growth advantages.Conclusions
Our study demonstrated that micromolar BPA inhibits proliferation of Sertoli cells by elevating oxidative stress while nanomolar BPA stimulates proliferation by promoting energy metabolism.General significance
Micromolar BPA inhibits cell proliferation by elevating oxidative stress while nanomolar BPA stimulates cell proliferation by promoting energy metabolism. 相似文献935.
Understanding miRNAs' regulatory networks and target genes could facilitate the development of therapies for human diseases such as cancer. Although much useful gene expression profiling data for tumor cell lines is available, microarray data for miRNAs and mRNAs in the human HepG2 cell line have only been compared with that of other cell lines separately. The relationship between miRNAs and mRNAs in integrated expression profiles for HepG2 cells is still unknown. To explore the miRNA–mRNA correlations in hepatocellular carcinoma (HCC) cells, we performed miRNA and mRNA expression profiling in HepG2 cells and normal liver HL-7702 cells at the genome scale using next-generation sequencing technology. We identified 193 miRNAs that are differentially expressed in these two cell lines. Of these, 89 miRNAs were down-regulated in HepG2 cells compared with HL-7702 cells, while 104 miRNAs were up-regulated. We also observed 3035 mRNAs that are significantly dys-regulated in HepG2 cells. We then performed an integrated analysis of the expression data for differentially expressed miRNAs and mRNAs and found several miRNA–mRNA pairs that are significantly correlated in HepG2 cells. Further analysis suggested that these differentially expressed genes were enriched in four tumorigenesis-related signaling pathways, namely, ErbB, JAK–STAT, mTOR, and WNT, which until now had not been fully reported. Our results could be helpful in understanding the mechanisms of HCC occurrence and development. 相似文献
936.
Insulin‐Like Growth Factor Binding Protein 4 Enhances Cardiomyocytes Induction in Murine‐Induced Pluripotent Stem Cells
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937.
为进一步确定黑曲霉菌株TCCC41650的生物转化能力,以雄甾-4-烯-3,17-二酮(Androstenedione)为底物,利用黑曲霉菌株TCCC41650进行催化,产物经纯化、重结晶后,通过单晶衍射鉴定为16β-羟基雄甾-4-烯-3,17-二酮。转化条件为:培养液pH 6.0,乙醇添加量为2%,投料浓度为1‰时,72 h转化率为85.8%。目前甾体研究领域对于C16β-羟基化的微生物转化未见报道,研究结果为C16β-羟基甾体药物的研发奠定了基础。 相似文献
938.
939.
940.
Di Ge Lei Han ShuYa Huang Nan Peng PengChong Wang Zheng Jiang Jing Zhao Le Su ShangLi Zhang Yun Zhang HsiangFu Kung BaoXiang Zhao JunYing Miao 《Autophagy》2014,10(6):957-971
MTOR, a central regulator of autophagy, is involved in cancer and cardiovascular and neurological diseases. Modulating the MTOR signaling balance could be of great significance for numerous diseases. No chemical activators of MTOR have been found, and the urgent challenge is to find novel MTOR downstream components. In previous studies, we found a chemical small molecule, 3-benzyl-5-((2-nitrophenoxy) methyl)–dihydrofuran-2(3H)-one (3BDO), that inhibited autophagy in human umbilical vein endothelial cells (HUVECs) and neuronal cells. Here, we found that 3BDO activated MTOR by targeting FKBP1A (FK506-binding protein 1A, 12 kDa). We next used 3BDO to detect novel factors downstream of the MTOR signaling pathway. Activation of MTOR by 3BDO increased the phosphorylation of TIA1 (TIA1 cytotoxic granule-associated RNA binding protein/T-cell-restricted intracellular antigen-1). Finally, we used gene microarray, RNA interference, RNA-ChIP assay, bioinformatics, luciferase reporter assay, and other assays and found that 3BDO greatly decreased the level of a long noncoding RNA (lncRNA) derived from the 3′ untranslated region (3′UTR) of TGFB2, known as FLJ11812. TIA1 was responsible for processing FLJ11812. Further experiments results showed that FLJ11812 could bind with MIR4459 targeting ATG13 (autophagy-related 13), and ATG13 protein level was decreased along with 3BDO-decreased FLJ11812 level. Here, we provide a new activator of MTOR, and our findings highlight the role of the lncRNA in autophagy. 相似文献