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Highly pathogenic avian influenza viruses (HPAIV) of subtype H5N1 not only cause a devastating disease in domestic chickens and turkeys but also pose a continuous threat to public health. In some countries, H5N1 viruses continue to circulate and evolve into new clades and subclades. The rapid evolution of these viruses represents a problem for virus diagnosis and control. In this work, recombinant vesicular stomatitis virus (VSV) vectors expressing HA of subtype H5 were generated. To comply with biosafety issues the G gene was deleted from the VSV genome. The resulting vaccine vector VSV*ΔG(HA) was propagated on helper cells providing the VSV G protein in trans. Vaccination of chickens with a single intramuscular dose of 2×108 infectious replicon particles without adjuvant conferred complete protection from lethal H5N1 infection. Subsequent application of the same vaccine strongly boosted the humoral immune response and completely prevented shedding of challenge virus and transmission to sentinel birds. The vaccine allowed serological differentiation of infected from vaccinated animals (DIVA) by employing a commercially available ELISA. Immunized chickens produced antibodies with neutralizing activity against multiple H5 viruses representing clades 1, 2.2, 2.5, and low-pathogenic avian influenza viruses (classical clade). Studies using chimeric H1/H5 hemagglutinins showed that the neutralizing activity was predominantly directed against the globular head domain. In summary, these results suggest that VSV replicon particles are safe and potent DIVA vaccines that may help to control avian influenza viruses in domestic poultry.  相似文献   
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Lung cancer is the most commonly diagnosed cancer worldwide with a high mortality rate. In this study, the therapeutic effect of combination valproic acid and niclosamide was investigated on human lung cancer cell line. The effects of the compounds alone and combination therapy on cell viability were determined by sulforhodamine B and adenosine 5′-triphosphate viability assays. Flow cytometry was used to determine the cell death mechanism and DNA damage levels responsible for the cytotoxic effects of combination therapy. The presence of apoptosis in cells was supported by fluorescence microscopy and also by using inhibitors of the apoptotic signaling pathway. The increase in cellular reactive oxygen species (ROS) level in combination therapy was determined by H2DCFDA staining. The effect of N-acetyl-l -cysteine combination on ROS increase was investigated on cell viability. In addition, the expression levels of the proteins associated with epigenetic regulation and cell death were analyzed by Western blotting and gene expression levels were determined using real-time quantitative polymerase chain reaction.It was observed that the combination therapy showed a cytotoxic effect on the A549 lung cancer cells compared to the individual use of the inhibitors. The absence of this effect on normal lung cells revealed the presence of a selective toxic effect. When the mechanism of cytotoxicity is examined, it has been observed that combination therapy initiates the activation of tumor necrosis receptors and causes apoptosis by activated caspase. It was also observed that this extrinsic apoptotic pathway was activated on the mitochondrial pathway. In addition, ER stress and mitochondrial membrane potential loss associated with increased ROS levels induce cell death. When the data in this study were evaluated, combination therapy caused a dramatic decrease in cell viability by inducing the extrinsic apoptotic pathway in lung cancer cell line. Therefore, it was concluded that it can be used as an effective and new treatment option for lung cancer.  相似文献   
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Objectives: Crimean Congo hemorrhagic fever (CCHF) is the second most common hemorrhagic fever worldwide. This study aimed to evaluate the oxidant–antioxidant balance of patients with CCHF by detecting dynamic thiol disulfide homeostasis (TDH), which is a novel oxidative stress marker, and other molecules, including paraoxonase (PON), arylesterase (ARES), ceruloplasmin (CLP), myeloperoxidase (MPO), and catalase.

Methods: This retrospective, cross-sectional, controlled study, which involved patients with CCHF and healthy volunteers, measured dynamic TDH using a novel automated method developed by Erel.

Results: We recruited 69 adult patients with CCHF (31 females, 38 males, median age 46 years). The case fatality rate was 1.49% (1/69). Increased disulfide/native thiol and disulfide/total thiol ratios, decreased total antioxidant status (TAS), and increased total oxidant status (TOS) were found in patients with CCHF. TAS, PON, and ARES values were found to be positively correlated with both native and total thiol levels, whereas TOS and CLP were negatively correlated with both, at a significant level. MPO activity was similar in both groups.

Discussion: This is the first study in the literature to evaluate dynamic TDH in CCHF. TDH shifts to the oxidative side in patients with CCHF, leading to an increase in TOS.  相似文献   

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This study investigated the distribution and accumulation of strontium (Sr) in the shoots and roots of Euphorbia macroclada (EU), Verbascum cheiranthifolium (VR), and Astragalus gummifer (AS), with respect to their potential use in phytoremediation. Plant samples and their associated soils were collected from the arid and semi-arid Keban mining area and were analyzed inductively by ICP-MS for Sr. Mean Sr values in the shoots, roots and soil were, respectively, 453, 243 and 398 mg kg?1 for E. macroclada; 149, 106 and 398 mg kg?1 for V. cheiranthifolium; and 278, 223 and 469 mg kg?1 for A. gummifer. The enrichment factors for root (ECR) and shoot (ECS) of these plants were lower than 1 or close to 1, except for the shoot of E. macroclada. The mean translocation factors (TLF) of these plants were higher than 1 and 2.08 for E. macroclada, 1.47 for V. cheiranthifolium, 1.18 for A. gummifer. It thus appeared that the shoots of these plants can be an efficient bioaccumulator plant for Sr and it can be used in cleaning or rehabilitating of the contaminated soil and areas by Sr because of their high translocation factors.  相似文献   
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Biological Trace Element Research - Metabolic diseases or injuries damage bone structure and self-renewal capacity. Trace elements and hydroxyapatite crystals are important in the development of...  相似文献   
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Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a distinct telomeric chromatin environment is a major requirement for the folding of yeast telomeres. We demonstrate that telomeres are not folded when cells enter replicative senescence, which occurs independently of short telomere length. Indeed, Sir2, Sin3 and Set2 protein levels are decreased during senescence and their absence may thereby prevent telomere folding. Additionally, we show that the homologous recombination machinery, including the Rad51 and Rad52 proteins, as well as the checkpoint component Rad53 are essential for establishing the telomere fold-back structure. This study outlines a method to interrogate telomere-subtelomere interactions at a single unmodified yeast telomere. Using this method, we provide insights into how the spatial arrangement of the chromosome end structure is established and demonstrate that telomere folding is compromised throughout replicative senescence.  相似文献   
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In this study, we aimed to research the effects of class‐I HDACs and glucose on differentiation of pancreatic islet derived mesenchymal stem cells (PI‐MSCs) to beta cells. Beta cell differentiation determined by flow cytometric analysis and gene expression levels of PDX1, PAX4, PAX6, NKX6.1, NGN3, INS2, and GLUT2. As a result the valproic acid, is an inhibitor of class‐I HDACs, caused the highest beta cell differentiation in PI‐MSCs. However, the cells in this group were at early stages of differentiation. Glucose co‐administration to this group carried the differentiation to higher levels, but these newly formed beta cells were not functional. Moreover, reduction in the levels of pluripotency factors that Oct3/4, c‐Myc, and Nanog were parallel to beta cell differentiation. Also, the levels of HDAC1 and acetylated H3/H4 were increased and methylated H3 was decreased by VPA treatment. In addition, we have detected over expression in genes of miR‐18a‐5p, miR‐19b‐5p, miR‐30d‐3p, miR‐124, miR‐146a‐5p, miR‐184, miR‐335, and miR‐433‐5p in parallel to beta cell differentiation. As the conclusion, this study is important for understanding the epigenetic mechanism that controls the beta cell differentation and it suggests new molecules that can be used for diagnosis, and treatment of diabetes. J. Cell. Biochem. 119: 455–467, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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The objective of the present study was to evaluate the effects of propolis, pollen, and caffeic acid phenethyl ester (CAPE) on tyrosine hydroxylase (TH) activity and total RNA levels of Nω-nitro-L-arginine methyl ester (L-NAME) inhibition of nitric oxide synthase in the heart, adrenal medulla, and hypothalamus of hypertensive male Sprague dawley rats. The TH activity in the adrenal medulla, heart, and hypothalamus of the rats was significantly increased in the L-NAME group vs. control (p < 0.05). Treatment with L-NAME led to a significant increase in blood pressure (BP) in the L-NAME group compared to control (p < 0.05). These data suggest that propolis, pollen, and CAPE may mediate diminished TH activity in the heart, adrenal medulla, and hypothalamus in hypertensive rats. The decreased TH activity may be due to the modulation and synthesis of catecholamines and BP effects. In addition, the binding mechanism of CAPE within the catalytic domain of TH was investigated by means of molecular modeling approaches. These data suggest that the amino acid residues, Glu429 and Ser354 of TH may play a pivotal role in the stabilization of CAPE within the active site as evaluated by molecular dynamics (MD) simulations. Gibbs binding free energy (ΔGbinding) of CAPE in complex with TH was also determined by post-processing MD analysis approaches (i.e. Poisson-Boltzmann Surface Area (MM-PBSA) method).  相似文献   
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