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991.
Organic acids as well as soluble sugars contribute highly to flavor and overall quality of citrus fruit. Citric acid level in fruit is influenced by several factors including environmental conditions. In this study, it was observed that different environments in two habitats (Ganzhou, Jiangxi; Songyang, Zhejiang) had minor effects on total soluble solids and citrus color index but had significant effects on organic acids levels, particularly on citric acid level, in fruit of “Newhall” and “SkaggsBonanza” navel oranges (Citrus sinensis). Expression of genes involved in citric acid biosynthesis and degradation (CitCS1, CitCS2, CitAco1, CitAco2, CitAco3, CitIDH1, CitIDH2, CitIDH3, CitGAD4, CitGAD5, and CitGS2) was analyzed in fruit grown in each of the two habitats. Citric acid biosynthesis-related citrate synthase genes were steadily expressed during navel orange fruit development, while degradation-related genes were differentially expressed. These findings suggested that the influence of different environments on fruit quality traits was predominant on the regulation of organic acids level, particularly on the degradation of citric acid. A cascade of CitAco3CitIDH1CitGS2 might be involved in citric acid degradation in response to different environments during fruit growth and development.  相似文献   
992.
B lymphocyte stimulator (BLyS) antagonists are new therapeutic reagents for treating the autoimmune diseases. Peptibodies can inhibit the bioactivity of BLyS, the same as other BLyS antagonists: decoyed BLyS receptors and anti-BLyS antibodies. In this study, a new optimized BLyS antagonist peptide was designed according to our previous work by the computer-aided homology modeling. Competitive ELISA showed that the peptide at 100 μg/ml could inhibit 54 % of the BCMA-Fc binding to BLyS. To maintain its stability and spatial conformation, the peptide was fused to human IgG1 Fc to form a peptide-Fc fusion protein—a novel peptibody by gene engineering. ELISA indicated that the peptibody could bind with BLyS in dosage-dependent manner as BCMA-Fc did. This study highlights the possibility of designing and optimizing BLyS antagonist peptides with high biopotency by the computer-aided design. Thus, these peptides could neutralize BLyS activity and be potential antagonists to treat autoimmune diseases related with BLyS overexpression.  相似文献   
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994.
We tried to identify the function of LINC01614 in lung adenocarcinoma (LUAD) and reveal its underlying mechanisms. qRT‐PCR was applied to assess the expression of LINC016014 in LUAD tissues, noncancerous tissues and cells. Through colony formation assay, MTT assay and apoptosis analysis, we examined the variation of cell proliferation and apoptosis ability after silencing LINC01614. Moreover, the targeting interactions among LINC01614, miR‐217 and FOXP1 were validated via luciferase reporter assay, and then, we regulated the expression of miR‐217 and FOXP1 to ascertain their importance in cell proliferation and apoptosis. LINC01614 and FOXP1 were found to be up‐regulated in LUAD tumours and cells, whereas miR‐217 was down‐regulated. The experiment showed that target‐specific selectivity exists between LINC01614‐miR‐217 and miR‐217‐FOXP1 3′UTR. Furthermore, we disclosed that inhibition of LINC01614 could activate miR‐217, which subsequently restrained FOXP1. It was proved that LINC01614 promoted FOXP1 by inhibiting miR‐217, which ultimately stimulated the development of LUAD.  相似文献   
995.
To meet human needs, the geographical location of lead changes during the process of mining lead ore to produce lead products for use by humans. These changes reveal the influence of human activities on lead distribution on the surface of Earth. In this study, a framework was built to analyze changes in lead distribution. Lead was traced through its life cycle using this framework. The provincial administrative unit in mainland of China was defined as the unit of space. The process of anthropogenic spatial transfer of lead was quantitatively analyzed by comparing lead distribution between different areas during each stage of its life cycle in 2010. The results showed that in 2010, around 60% of domestic lead resources were distributed in the Inner Mongolia Autonomous Region, Yunnan Province, and other locations in China. Nearly 80% of the refined lead was produced in Henan, Anhui, Hunan, Yunnan, and Jiangsu provinces. More than 50% of lead products were fabricated and manufactured in Zhejiang, Jiangsu, Shandong, and Hebei provinces. The distribution of lead usage and scrap recovery was relatively uniform (approximately 21 provinces accounted for 1% to 6% of all scrap in the country), although lead products and scrap were mainly distributed in Guangdong, Shandong, Jiangsu, and Zhejiang provinces, which together accounted for nearly 40% of the total. The recycling of lead scrap was mainly concentrated in Anhui (around 57% of the total). Overall, during the whole process, from the mining lead ore from the lithosphere to each stage of the product life cycle, lead was gradually transferred from the south and north of China to the central area and, finally, to the eastern coastal areas.  相似文献   
996.
997.
Antimicrobial peptides (AMPs), as evolutionarily conserved components of innate immune system, protect against pathogens including bacteria, fungi, viruses, and parasites. In general, AMPs are relatively small peptides (<10 kDa) with cationic nature and amphipathic structure and have modes of action different from traditional antibiotics. Up to now, there are more than 19 000 AMPs that have been reported, including those isolated from nature sources or by synthesis. They have been considered to be promising substitutes of conventional antibiotics in the quest to address the increasing occurrence of antibiotic resistance. However, most AMPs have modest direct antimicrobial activity, and their mechanisms of action, as well as their structure–activity relationships, are still poorly understood. Computational strategies are invaluable assets to provide insight into the activity of AMPs and thus exploit their potential as a new generation of antimicrobials. This article reviews the advances of AMP databases and computational tools for the prediction and design of new active AMPs. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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1000.
In order to assess heavy metal pollution of sediment samples collected from Shuangtaizi estuary, contamination factor (CF) and multivariate statistical analyses, including principal component analysis (PCA), cluster analysis (CA) and correlation analysis, are carried out in this paper. CF confirms that Pb, Cu and Hg concentrations are very low and all fall within the range of background, while Zn and Cd demonstrate moderate contamination (in A10, A13, A15, A16 and A17 sites) and very high contamination (in A10, A13, A15 and A17 sites), respectively. The PCA indicates that four significant principal components (PCs) are extracted, explaining 88.959% of total variance, which suggests that Pb, Cu and Zn are mainly associated with organic carbon (OC). The result from CA is consistent with that obtained from PCA, classifying that the heavy metals in two clusters derive from different sources. Correlation analysis supports the conclusions from PCA and CA, elucidating the relationships between heavy metals and particle sizes of the sediments.  相似文献   
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