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101.
Hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) has a poor prognosis with high in-hospital mortality. Hepatic and circulating inflammatory cytokines, such as fibrinogen like protein 2 (fgl2), FasL/Fas, and TNFα/TNFR1, play a significant role in the pathophysiology of ACLF. This study aimed to investigate the therapeutic effect of recombinant adenoviral vectors carrying constructed DNA code for non-native microRNA (miRNA) targeting mouse fgl2 (mfgl2) or both mFas and mTNFR1 on murine hepatitis virus (MHV)-3-induced fulminant hepatitis in BALB/cJ mice. Artificial miRNA eukaryotic expression plasmids against mfgl2, mFas, and mTNFR1 were constructed, and their inhibitory effects on the target genes were confirmed in vitro. pcDNA6.2-mFas-mTNFR1- miRNA,which expresses miRNA against both mFas and mTNFR1 simultaneously,was constructed. To construct a miRNA adenovirus expression vector against mfgl2, pcDNA6.2-mfgl2-miRNA was cloned using Gateway technology. Ad-mFas-mTNFR1- miRNA was also constructed by the same procedure. Adenovirus vectors were delivered by tail-vein injection into MHV-3-infected BALB/cJ mice to evaluate the therapeutic effect. 8 of 18 (44.4%) mice recovered from fulminant viral hepatitis in the combined interference group treated with Ad-mfgl2-miRNA and Ad-mFas-mTNFR1-miRNA. But only 4 of 18 (22.2%) mice receiving Ad-mfgl2-miRNA and 3 of 18 (16.7%) mice receiving Ad-mFas-mTNFR1- miRNA survived. These adenovirus vectors significantly ameliorated inflammatory infiltration, fibrin deposition, hepatocyte necrosis and apoptosis, and prolonged survival time. Our data illustrated that combined interference using adenovirus-mediated artificial miRNAs targeting mfgl2, mFas, and mTNFR1 might have significant therapeutic potential for the treatment of fulminant hepatitis. 相似文献
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Wei‐Guang Wang Zhao‐Yuan Wu Rui Chen Hai‐Zhou Li Hong‐Mei Li Yuan‐Dan Li Rong‐Tao Li Huai‐Rong Luo 《化学与生物多样性》2013,10(6):1061-1071
Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05). 相似文献
105.
Jianmei Luo Meiling Chi Hongyu Wang Huanhuan He Minghua Zhou 《Bioprocess and biosystems engineering》2013,36(12):1889-1896
A convenient and promising alternative to surface modification of carbon mesh anode was fulfilled by electrochemical oxidation in the electrolyte of nitric acid or ammonium nitrate at ambient temperature. It was confirmed that such an anode modification method was low cost and effective not only in improving the efficiency of power generation in microbial fuel cells (MFCs) for synthetic wastewater treatment, but also helping to reduce the period for MFCs start-up. The MFCs with anode modification in electrolyte of nitric acid performed the best, achieving a Coulombic efficiency enhancement of 71 %. As characterized, the electrochemical modification resulted in the decrease of the anode potential and internal resistance but the increase of current response and nitrogen-containing and oxygen-containing functional groups on the carbon surface, which might contribute to the enhancement on the performances of MFCs. 相似文献
106.
Shu Xu Jianying Luo Xiayan Pan Xiaoyu Liang Jian Wu Wenjun Zheng Changjun Chen Yiping Hou Hongyu Ma Mingguo Zhou 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(8):1660-1670
The plant-pathogenic bacterium Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of bacterial blight, which is one of the most serious diseases of rice. Xoo has been studied for over one century, and much has been learned about it, but proteomic investigation has been neglected. In this study, proteome reference maps of Xoo were constructed by two-dimensional gel electrophoresis, and 628 spots in the gels representing 469 different protein species were identified with MALDI-TOF/TOF MS. The identified spots were assigned to 15 functional categories according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and the annotations from the National Center for Biotechnology Information (NCBI) database. The data set has been deposited in the World-2DPAGE database (Database ID: 0044). In addition, comparative proteomic analysis revealed that proteins related to the TonB-dependent transportation system and energy metabolism are involved in the phenazine-1-carboxylic acid resistance in Xoo. In conclusion, we have established a proteome database for Xoo and have used this database in a comparative proteomic analysis that identified proteins potentially contributing to phenazine-1-carboxylic acid resistance in Xoo. 相似文献
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109.
Yuxia Yang Wei Ma Dan Wu Yu Huang Hongge Li Junhua Zou Yanju Zhang Meifu Feng Jianyuan Luo 《PloS one》2013,8(7)
Background
Hematopoietic stem cell (HSC) regulation is highly dependent on interactions with the marrow microenvironment, of which osteogenic cells play a crucial role. While evidence is accumulating for an important role of intrinsic miR-17 in regulating HSCs and HPCs, whether miR-17 signaling pathways are also necessary in the cell-extrinsic control of hematopoiesis hereto remains poorly understood.Methodology/Principal Findings
Using the immortalized clone with the characteristics of osteoblasts, FBMOB-hTERT, in vitro expansion, long-term culture initiating cell (LTC-IC) and non-obese diabetic/severe combined immunodeficient disease (NOD/SCID) mice repopulating cell (SRC) assay revealed that the ectopic expression of miR-17 partly promoted the ability of FBMOB-hTERT to support human cord blood (CB) CD34+ cell expansion and maintain their multipotency. It also seemed that osteoblastic miR-17 was prone to cause a specific expansion of the erythroid lineage. Conversely, deficient expression of miR-17 partly inhibited the hematopoietic supporting ability of FBMOB-hTERT. We further identified that HIF-1α is responsible for, at least in part, the promoted hematopoietic supporting ability of FBMOB-hTERT caused by miR-17. HIF-1α expression is markedly enhanced in miR-17 overexpressed FBMOB-hTERT upon interaction with CB CD34+ cells compared to other niche associated factors. More interestingly, the specific erythroid lineage expansion of CB CD34+ cells caused by osteoblastic miR-17 was abrogated by HIF-1α knock down.Conclusion/Significance
Our data demonstrated that CB CD34+ cell expansion can be partly promoted by osteoblastic miR-17, and in particular, ectopic miR-17 can cause a specific expansion of the erythroid lineage through augmenting HIF-1α in osteoblasts. 相似文献110.
Jun Liu Yan Luo Hengtao Ge Chengquan Han Hui Zhang Yongsheng Wang Jianmin Su Fusheng Quan Mingqing Gao Yong Zhang 《PloS one》2013,8(6)
The present study was conducted to determine whether recombinant human β-defensin-3 (rHBD3) in the milk of transgenic goats has an anti-bacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Streptococcus agalactiae (S. agalactiae) that could cause mastitis. A HBD3 mammary-specific expression vector was transfected by electroporation into goat fetal fibroblasts which were used to produce fourteen healthy transgenic goats by somatic cell nuclear transfer. The expression level of rHBD3 in the milk of the six transgenic goats ranged from 98 to 121 µg/ml at 15 days of lactation, and was maintained at 90–111 µg/ml during the following 2 months. Milk samples from transgenic goats showed an obvious inhibitory activity against E. coli, S. aureus and S. agalactiae in vitro. The minimal inhibitory concentrations of rHBD3 in milk against E. coli, S. aureus and S. agalactiae were 9.5–10.5, 21.8–23.0 and 17.3–18.5 µg/mL, respectively, which was similar to those of the HBD3 standard (P>0.05). The in vivo anti-bacterial activities of rHBD3 in milk were examined by intramammary infusion of viable bacterial inoculums. We observed that 9/10 and 8/10 glands of non-transgenic goats infused with S. aureus and E. coli became infected. The mean numbers of viable bacteria went up to 2.9×103 and 95.4×103 CFU/ml at 48 h after infusion, respectively; the mean somatic cell counts (SCC) in infected glands reached up to 260.4×105 and 622.2×105 cells/ml, which were significantly higher than the SCC in uninfected goat glands. In contrast, no bacteria was presented in glands of transgenic goats and PBS-infused controls, and the SSC did not significantly change throughout the period. Moreover, the compositions and protein profiles of milk from transgenic and non-transgenic goats were identical. The present study demonstrated that HBD3 were an effective anti-bacterial protein to enhance the mastitis resistance of dairy animals. 相似文献