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11.
By nature of their segmented RNA genome, influenza A viruses (IAVs) have the potential to generate variants through a reassortment process. The influenza nonstructural (NS) gene is critical for a virus to counteract the antiviral responses of the host. Therefore, a newly acquired NS segment potentially determines the replication efficiency of the reassortant virus in a range of different hosts. In addition, the C-terminal PDZ-binding motif (PBM) has been suggested as a pathogenic determinant of IAVs. To gauge the pandemic potential from human and avian IAV reassortment, we assessed the replication properties of NS-reassorted viruses in cultured cells and in the lungs of mice and determined their transmissibility in guinea pigs. Compared with the recombinant A/Korea/01/2009 virus (rK09; 2009 pandemic H1N1 strain), the rK09/VN:NS virus, in which the NS gene was adopted from the A/Vietnam/1203/2004 virus (a human isolate of the highly pathogenic avian influenza H5N1 virus strains), exhibited attenuated virulence and reduced transmissibility. However, the rK09/VN:NS-PBM virus, harboring the PBM in the C-terminus of the NS1 protein, recovered the attenuated virulence of the rK09/VN:NS virus. In a guinea pig model, the rK09/VN:NS-PBM virus showed even greater transmission efficiency than the rK/09 virus. These results suggest that the PBM in the NS1 protein may determine viral persistence in the human and avian IAV interface.  相似文献   
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The effects of aluminum on lipid peroxidation and activities of antioxidative enzymes were investigated in detached rice leaves treated with 0 to 5 mM AlCl3 at pH 4.0 in the light. AlCl3 enhanced the content of malondialdehyde but not the content of H2O2. Superoxide dismutase activity was reduced by AlCl3, while catalase and glutathione reductase activities were increased. Peroxidase and ascorbate peroxidase activities were increased only after prolonged treatment, when toxicity occurred. The results give evidence that Al treatment caused oxidative stress and in turn, it caused lipid peroxidation.  相似文献   
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The present study was reported the effect of probiotics and herbals mixture supplementation diet on growth, blood constituents, and nonspecific immune response in olive flounder Paralichthys olivaceus against Streptococcus parauberis on weeks 1, 2, 4, 6, 8, 10, and 12 after injected intraperitoneally (i.p.) with 50 μl of PBS (phosphate buffer saline) containing S. parauberis (2.1 × 10? CFU ml?1). The initial weight did not significantly increased in supplementation diet group from 1 to 4 weeks, whereas it was significantly increased from weeks 6 to 12 as compared to fish fed without supplementation diet. The serum aspartate aminotransferase (SGOT) and alanine aminotransferase (SGPT) activities significantly increased from weeks 4 to 12 in infected fish fed with supplementation diet compared to fish fed without supplementation diet. However, the total protein (TP) and glucose (GLU) levels were significantly increased in infected fish fed with supplementation diet after 6 weeks. The phagocytic, respiratory burst, complement, and lysozyme activities significantly enhanced in infected fish fed with supplementation diet from weeks 4 to 12 as compared to fish fed without supplementation diet. These results suggested that different probiotics and herbals mixture supplementation diet enhanced the growth, blood biochemical constituents, and nonspecific immunity in olive flounder against S. parauberis.  相似文献   
15.
We isolated Mesoflavibacter zeaxanthinifaciens S86 as xylanase-producing bacteria from seawater sampled in Micronesia. Analysis of the M. zeaxanthinifaciens genome revealed that it contains a single circular chromosome of 3,704,661 bp with 3,249 putative open reading frames.  相似文献   
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Ahn KS  Kim YJ  Kim M  Lee BH  Heo SY  Kang MJ  Kang YK  Lee JW  Lee KK  Kim JH  Nho WG  Hwang SS  Woo JS  Park JK  Park SB  Shim H 《Theriogenology》2011,75(5):933-939
Animals with a targeted disruption of genes can be produced by somatic cell nuclear transfer (SCNT). However, difficulties in clonal selection of somatic cells with a targeted mutation often result in heterogeneous nuclear donor cells, including gene-targeted and non-targeted cells, and impose a risk of producing undesired wildtype cloned animals after SCNT. In addition, the efficiency of cloning by SCNT has remained extremely low. Most cloned embryos die in utero, and the few that develop to term show a high incidence of postnatal death and abnormalities. In the present study, resurrection of an alpha-1,3-galactosyltransferase (αGT) gene-targeted miniature pig by recloning using postmortem ear skin fibroblasts was attempted. Three cloned piglets were produced from the first round of SCNT, including one stillborn and two who died immediately after birth due to respiratory distress syndrome and cardiac dysfunction. Among the three piglets, two were confirmed to be αGT gene-targeted. Fibroblasts derived from postmortem ear skin biopsies were used as nuclear donor cells for the second round of SCNT, and a piglet was produced. As expected, PCR and Southern analyses confirmed that the piglet produced from recloning was αGT gene-targeted. Currently, the piglet is fourteen months of age, and no overt health problems have been observed. Results from the present study demonstrate that loss of an invaluable animal, such as a gene-targeted miniature pig, may be rescued by recloning, with assurance of the desired genetic modification.  相似文献   
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Cytochrome P450 enzymes (CYP or P450) 46A1 and 27A1 play important roles in cholesterol elimination from the brain and retina, respectively, yet they have not been quantified in human organs because of their low abundance and association with membrane. On the basis of our previous development of a multiple reaction monitoring (MRM) workflow for measurements of low-abundance membrane proteins, we quantified CYP46A1 and CYP27A1 in human brain and retina samples from four donors. These enzymes were quantified in the total membrane pellet, a fraction of the whole tissue homogenate, using 1?N-labled recombinant P450s as internal standards. The average P450 concentrations/mg of total tissue protein were 345 fmol of CYP46A1 and 110 fmol of CYP27A1 in the temporal lobe, and 60 fmol of CYP46A1 and 490 fmol of CYP27A1 in the retina. The corresponding P450 metabolites were then measured in the same tissue samples and compared to the P450 enzyme concentrations. Investigation of the enzyme-product relationships and analysis of the P450 measurements based on different signature peptides revealed a possibility of retina-specific post-translational modification of CYP27A1. The data obtained provide important insights into the mechanisms of cholesterol elimination from different neural tissues.  相似文献   
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Objective: To estimate the association between body mass index (BMI) and health‐related quality of life (HRQL) and examine whether joint pain and obesity‐related comorbidities mediate the BMI‐HRQL association. Research Methods and Procedures: Population‐based survey data from the 1999 Behavioral Risk Factor Surveillance Survey. Adults (N = 155, 989) were classified according to BMI as underweight (<18.5 kg/m2), desirable weight (18.5 to 24.9 kg/m2), overweight (25 to 29.9 kg/m2), obese class I (30 to 34.9 kg/m2), obese class II (35 to 39.9 kg/m2), and obese class III (≥40 kg/m2). Data including general health status, unhealthy days in the past 30 caused by physical problems and mental problems, and total unhealthy days in the past 30 were collected. Results: After adjusting for age, sex, race, smoking, education, and income, we observed J‐shaped associations between BMI and HRQL. Compared with desirable weight adults, underweight, overweight, and obesity classes I, II, and III adults [odds ratio (OR) = 1.57, 1.19, 1.95, 2.72, and 4.36, respectively] were significantly (p < 0.001) more likely to report fair/poor general health status. For unhealthy days caused by physical problems, the corresponding ORs were 1.51, 1.15, 1.66, 2.27, and 3.61 (p < 0.001). For unhealthy days caused by mental problems, the ORs were 1.35, 1.14 1.43, 1.57, and 2.25 (p < 0.001). For total unhealthy days, the corresponding ORs were 1.27, 1.09, 1.37, 1.73, and 2.46 (p < 0.01). Adding joint pain and obesity‐related comorbidities into models attenuated BMI‐HRQL associations. Discussion: Associations between BMI and HRQL indices were J‐shaped. Joint pain and comorbidities may mediate BMI‐HRQL associations.  相似文献   
19.
MicroRNAs (miRNAs) are a class of highly conserved small non-coding RNA molecules that play a pivotal role in several cellular functions. In this study, miRNA and messenger RNA (mRNA) profiles were examined by Illumina microarray in mouse embryonic stem cells (ESCs) derived from parthenogenetic, androgenetic, and fertilized blastocysts. The global analysis of miRNA-mRNA target pairs provided insight into the role of miRNAs in gene expression. Results showed that a total of 125 miRNAs and 2394 mRNAs were differentially expressed between androgenetic ESCs (aESCs) and fertilized ESCs (fESCs), a total of 42 miRNAs and 87 mRNAs were differentially expressed between parthenogenetic ESCs (pESCs) and fESCs, and a total of 99 miRNAs and 1788 mRNAs were differentially expressed between aESCs and pESCs. In addition, a total of 575, 5 and 376 miRNA-mRNA target pairs were observed in aESCs vs. fESCs, pESCs vs. fESCs, and aESCs vs. pESCs, respectively. Furthermore, 15 known imprinted genes and 16 putative uniparentally expressed miRNAs with high expression levels were confirmed by both microarray and real-time RT-PCR. Finally, transfection of miRNA inhibitors was performed to validate the regulatory relationship between putative maternally expressed miRNAs and target mRNAs. Inhibition of miR-880 increased the expression of Peg3, Dyrk1b, and Prrg2 mRNA, inhibition of miR-363 increased the expression of Nfat5 and Soat1 mRNA, and inhibition of miR-883b-5p increased Nfat5, Tacstd2, and Ppapdc1 mRNA. These results warrant a functional study to fully understand the underlying regulation of genomic imprinting in early embryo development.  相似文献   
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