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991.
Hongren Qu Limin Yang Shanshan Meng Lei Xu Yuhai Bi Xiaojuan Jia Jing Li Lei Sun Wenjun Liu 《PloS one》2013,8(3)
Chicken interferon α (ChIFN-α) and ChIFN-β are type I IFNs that are important antiviral cytokines in the innate immune system. In the present study, we identified the virus-induced expression of ChIFN-α and ChIFN-β in chicken fibroblast DF-1 cells and systematically evaluated the antiviral activities of recombinant ChIFN-α and ChIFN-β by cytopathic-effect (CPE) inhibition assays. We found that ChIFN-α exhibited stronger antiviral activity than ChIFN-β in terms of inhibiting the replication of vesicular stomatitis virus, Newcastle disease virus and avian influenza virus, respectively. To elucidate the mechanism of differential antiviral activities between the two ChIFNs, we measured the relative mRNA levels of IFN-stimulated genes (ISGs) in IFN-treated DF-1 cells by real-time PCR. ChIFN-α displayed greater induction potency than ChIFN-β on several ISGs encoding antiviral proteins and MHC-I, whereas ChIFN-α was less potent than ChIFN-β for inducing ISGs involved in signaling pathways. In conclusion, ChIFN-α and ChIFN-β presented differential induction potency on various sets of ISGs, and the stronger antiviral activity of ChIFN-α is likely attributed to the greater expression levels of downstream antiviral ISGs. 相似文献
992.
Fengjiang Li Naiqin Wu Houyuan Lu Jianping Zhang Weilin Wang Mingzhi Ma Xiaohu Zhang Xiaoyan Yang 《PloS one》2013,8(3)
Mollusk remains are abundant in archaeological sites in the Guanzhong Basin of Northwestern China, providing good opportunities for investigations into the use of mollusks by prehistoric humans. Here we report on freshwater gastropod and bivalve mollusks covering the time interval from about 5600 to 4500 cal. yrs BP from sites of Mid-Late Neolithic age. They are identified as Cipangopaludina chinensis and Unio douglasiae, both of which are currently food for humans. The shells are well preserved and have no signs of abrasion. They are all freshwater gastropods and bivalves found in pits without water-reworked deposits and have modern representatives which can be observed in rivers, reservoirs, and paddy fields in the studied region. Mollusk shells were frequently recovered in association with mammal bones, lithic artifacts, and pottery. These lines of evidence indicate that the mollusks are the remains of prehistoric meals. The mollusk shells were likely discarded into the pits by prehistoric humans after the flesh was eaten. However, these mollusk remains may not have been staple food since they are not found in large quantities. Mollusk shell tools and ornaments are also observed. Shell tools include shell knives, shell reaphooks and arrowheads, whereas shell ornaments are composed of pendants and loops. All the shell tools and ornaments are made of bivalve mollusks and do not occur in large numbers. The finding of these freshwater mollusk remains supports the view that the middle Holocene climate in the Guanzhong Basin may have been warm and moist, which was probably favorable to freshwater mollusks growing and developing in the region. 相似文献
993.
994.
Growth differentiation factor 15 (GDF15), a direct target gene of p53, is a multifunctional member of the TGF-β/BMP superfamily. GDF15 can be induced and is implicated as a key secretory cytokine in response to multiple cellular stimuli. Accumulating evidence indicates that GDF15 is associated with the development and prognosis of diabetes mellitus, while whether GDF15 can be induced by high glucose is unknown. In the present study, we revealed that high glucose could induce GDF15 expression and secretion in cultured human umbilical vein endothelial cells in a ROS- and p53-dependent manner. Inhibition of high glucose-induced GDF15 expression by siRNA demonstrated that adaptively induced GDF15 played a protective role against high glucose-induced human umbilical vein endothelial cell apoptosis via maintaining the active state of PI3K/Akt/eNOS pathway and attenuating NF-κB/JNK pathway activation. The protective effects of GDF15 were probably achieved by inhibiting ROS overproduction in high glucose-treated human umbilical vein endothelial cells in a negative feedback manner. Our results suggest that high glucose can promote GDF15 expression and secretion in human umbilical vein endothelial cells, which in turn attenuates high glucose-induced endothelial cell apoptosis. 相似文献
995.
996.
MiRNAs are a class of non-coding small RNAs that play important roles in the regulation of gene expression. Although plant miRNAs have been extensively studied in model systems, less is known in other plants with limited genome sequence data, including eggplant (Solanum melongena L.). To identify miRNAs in eggplant and their response to Verticillium dahliae infection, a fungal pathogen for which clear understanding of infection mechanisms and effective cure methods are currently lacking, we deep-sequenced two small RNA (sRNA) libraries prepared from mock-infected and infected seedlings of eggplants. Specifically, 30,830,792 reads produced 7,716,328 unique miRNAs representing 99 known miRNA families that have been identified in other plant species. Two novel putative miRNAs were predicted with eggplant ESTs. The potential targets of the identified known and novel miRNAs were also predicted based on sequence homology search. It was observed that the length distribution of obtained sRNAs and the expression of 6 miRNA families were obviously different between the two libraries. These results provide a framework for further analysis of miRNAs and their role in regulating plant response to fungal infection and Verticillium wilt in particular. 相似文献
997.
Yang Jiang Bi-Qing Li Yuchao Zhang Yuan-Ming Feng Yu-Fei Gao Ning Zhang Yu-Dong Cai 《PloS one》2013,8(6)
Most of pyruvoyl-dependent proteins observed in prokaryotes and eukaryotes are critical regulatory enzymes, which are primary targets of inhibitors for anti-cancer and anti-parasitic therapy. These proteins undergo an autocatalytic, intramolecular self-cleavage reaction in which a covalently bound pyruvoyl group is generated on a conserved serine residue. Traditional detections of the modified serine sites are performed by experimental approaches, which are often labor-intensive and time-consuming. In this study, we initiated in an attempt for the computational predictions of such serine sites with Feature Selection based on a Random Forest. Since only a small number of experimentally verified pyruvoyl-modified proteins are collected in the protein database at its current version, we only used a small dataset in this study. After removing proteins with sequence identities >60%, a non-redundant dataset was generated and was used, which contained only 46 proteins, with one pyruvoyl serine site for each protein. Several types of features were considered in our method including PSSM conservation scores, disorders, secondary structures, solvent accessibilities, amino acid factors and amino acid occurrence frequencies. As a result, a pretty good performance was achieved in our dataset. The best 100.00% accuracy and 1.0000 MCC value were obtained from the training dataset, and 93.75% accuracy and 0.8441 MCC value from the testing dataset. The optimal feature set contained 9 features. Analysis of the optimal feature set indicated the important roles of some specific features in determining the pyruvoyl-group-serine sites, which were consistent with several results of earlier experimental studies. These selected features may shed some light on the in-depth understanding of the mechanism of the post-translational self-maturation process, providing guidelines for experimental validation. Future work should be made as more pyruvoyl-modified proteins are found and the method should be evaluated on larger datasets. At last, the predicting software can be downloaded from http://www.nkbiox.com/sub/pyrupred/index.html. 相似文献
998.
Pengchao Li Jinbao Gu Xiao Yang Hongzhou Cai Jun Tao Xuejian Yang Qiang Lu Zengjun Wang Changjun Yin Min Gu 《PloS one》2013,8(8)
Background
A functional -94 insertion/deletion polymorphism (rs28362491) in the promoter of the NFKB1 gene was reported to influence NFKB1 expression and confer susceptibility to different types of cancer. This study aims to determine whether the polymorphism is associated with risk of bladder cancer.Materials and methods
TaqMan assay was used to determine genotype among 609 cases and 640 controls in a Chinese population. Logistic regression was used to assess the association between the polymorphism and bladder cancer risk, and quantitative real-time polymerase chain reaction was used to determine NFKB1 mRNA expression.Results
Compared with the ins/ins/ins/del genotypes, the del/del genotype was associated with a significantly increased risk of bladder cancer [adjusted odd ratio (OR) = 1.92, 95% confidence interval (CI) = 1.42–2.59]. The increased risk was more prominent among subjects over 65 years old (OR = 2.37, 95% CI = 1.52–3.70), male subjects (OR = 1.97, 95% CI = 1.40–2.79) and subjects with self-reported family history of cancer (OR = 3.59, 95% CI = 1.19–10.9). Furthermore, the polymorphism was associated with a higher risk of developing non-muscle invasive bladder cancer (OR = 2.07, 95% CI = 1.51–2.85), grade 1 bladder cancer (OR = 2.40, 95% CI = 1.68–3.43), single tumor bladder cancer (OR = 2.04, 95% CI = 1.48–2.82) and smaller tumor size bladder cancer (OR = 2.10, 95% CI = 1.51–2.92). The expression of NFKB1 mRNA in bladder cancer tissues with homozygous insertion genotype was higher than that with deletion allele.Conclusions
In conclusion, the -94 ins/del ATTG polymorphism in NFKB1 promoter may contribute to the etiology of bladder cancer in the Chinese population. 相似文献999.
Yun-Song Wang Rong Huang Yan Li Wen-Bin Shang Fei Chen Hong-Bin Zhang Jing-Hua Yang 《Phytochemistry letters》2013,6(1):26-30
A pair of novel tetrahydrobenzofuran derivatives with a unique C18 carbon skeleton, panamonon A (1) and B (2), was isolated from the leaves and twigs of Litsea panamonja (Nees) Hook. f. These new compounds contain an unprecedented C18 carbon skeleton consisting of a characteristic tetrahydrobenzofuran-2,5(3H,6H)-dione core with a biosynthetically extended geranyl side chain, designated as “panamonane”.Highlights? A pair of novel tetrahydrobenzofuran derivatives with a unique C18 carbon skeleton was isolated. ? The new compounds possess an unprecedented C18 carbon skeleton and are designated as “panamonane”. ? They are featured with a tetrahydrobenzofuran-2,5(3H,6H)-dione moiety and a geranyl side chain. ? The plausible biosynthetic pathways of them were discussed. 相似文献
1000.
Wei Zhao Xiaoying Zeng Tao Zhang Lan Wang Guangyu Yang Yong-Kuan Chen Qiufen Hu Mingming Miao 《Phytochemistry letters》2013,6(2):179-182
Two new flavonoids, fistulaflavonoids B and C (1–2), together with five known flavonoids (3–7) were isolated from the bark and stems of Cassia fistula. Their structures were determined by means of HRESIMS, extensive 1D and 2D NMR spectroscopic studies and chemical evidences. The anti-tobacco mosaic virus (anti-TMV) activity of the isolated flavonoids was also evaluated. The results showed that compounds 1 and 2 showed high anti-TMV activity with inhibition rate of 28.5% and 31.3%, which is higher than that of Ningnanmycin (24.7%). Compounds 4–7 showed modest anti-TMV activity with inhibition rate of 18.5%, 22.7%, 16.4%, and 15.3%, respectively. 相似文献