5,033 research outputs found

    Effect of backwashing on perchlorate removal in fixed bed biofilm reactors

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    The influence of backwashing on biological perchlorate reduction was evaluated in two laboratory scale fixed bed biofilm reactors using 1- or 3-mm glass beads as support media. Influent perchlorate concentrations were 50 μg/L and acetate was added as the electron donor at a concentration of 2 mg C/L. Perchlorate removal was evaluated at various influent dissolved oxygen (DO) concentrations. Complete perchlorate removal was achieved with an influent DO concentration of 1 mg/L resulting in bulk phase DO concentrations below the detection limit of 0.01 mg/L. The influence of increasing influent DO concentrations for 12 h periods was evaluated before and after individual backwash events. Partial perchlorate removal was achieved with an influent DO concentration of 3.5 mg/L before a strong backwash (bulk phase DO concentrations of approximately 0.2 mg/L), while no perchlorate removal was observed after the strong backwash at the same influent DO level (bulk phase DO concentrations of approximately 0.8 mg/L). The immediate effect of backwashing depended on influent DO concentrations. With influent DO concentrations of 1 mg/L, strong backwashing resulted in a brief (\u3c12 h) increase of effluent perchlorate concentrations up to 20 μg/L; more pronounced effects were observed with influent DO concentrations of 3 mg/L. Daily weak backwashing had a small and, over time, decreasing negative influence on perchlorate reduction, while daily strong backwashing ultimately resulted in the breakdown of perchlorate removal with influent DO concentrations of 3 mg/L

    Plasmacytoid Dendritic Cells Contribute to the Protective Immunity Induced by Intranasal Treatment with Fc-fused Interleukin-7 against Lethal Influenza Virus Infection

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    Developing a novel vaccine that can be applied against multiple strains of influenza virus is of utmost importance to human health. Previously, we demonstrated that the intranasal introduction of Fc-fused IL-7 (IL-7-mFc), a long-acting cytokine fusion protein, confers long-lasting prophylaxis against multiple strains of influenza A virus (IAV) by inducing the development of lung-resident memory-like T cells, called TRM-like cells. Here, we further investigated the mechanisms of IL-7-mFc-mediated protective immunity to IAVs. First, we found that IL-7-mFc treatment augments the accumulation of pulmonary T cells in 2 ways: recruiting blood circulating T cells into the lung and expanding T cells at the lung parenchyma. Second, the blockade of T cell migration from the lymph nodes (LNs) with FTY720 treatment was not required for mounting the protective immunity to IAV with IL-7-mFc, suggesting a more important role of IL-7 in T cells in the lungs. Third, IL-7-mFc treatment also recruited various innate immune cells into the lungs. Among these cells, plasmacytoid dendritic cells (pDCs) play an important role in IL-7-mFc-mediated protective immunity through reducing the immunopathology and increasing IAV-specific cytotoxic T lymphocyte (CTL) responses. In summary, our results show that intranasal treatment with IL-7-mFc modulates pulmonary immune responses to IAV, affecting both innate and adaptive immune cells. ? 2017. The Korean Association of Immunologists.112Ysciescopuskc

    Characterization of Fabry mice treated with recombinant adeno-associated virus 2/8-mediated gene transfer

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    <p>Abstract</p> <p>Background</p> <p>Enzyme replacement therapy (ERT) with α-galactosidase A (α-Gal A) is currently the most effective therapeutic strategy for patients with Fabry disease, a lysosomal storage disease. However, ERT has limitations of a short half-life, requirement for frequent administration, and limited efficacy for patients with renal failure. Therefore, we investigated the efficacy of recombinant adeno-associated virus (rAAV) vector-mediated gene therapy for a Fabry disease mouse model and compared it with that of ERT.</p> <p>Methods</p> <p>A pseudotyped rAAV2/8 vector encoding α-Gal A cDNA (rAAV2/8-hAGA) was prepared and injected into 18-week-old male Fabry mice through the tail vein. The α-Gal A expression level and globotriaosylceramide (Gb3) levels in the Fabry mice were examined and compared with Fabry mice with ERT. Immunohistochemical and ultrastructural studies were conducted.</p> <p>Results</p> <p>Treatment of Fabry mice with rAAV2/8-hAGA resulted in the clearance of accumulated Gb3 in tissues such as liver, spleen, kidney, heart, and brain with concomitant elevation of α-Gal A enzyme activity. Enzyme activity was elevated for up to 60 weeks. In addition, expression of the α-Gal A protein was identified in the presence of rAAV2/8-hAGA at 6, 12, and 24 weeks after treatment. α-Gal A activity was significantly higher in the mice treated with rAAV2/8-hAGA than in Fabry mice that received ERT. Along with higher α-Gal A activity in the kidney of the Fabry mice treated with gene therapy, immunohistochemical studies showed more α-Gal A expression in the proximal tubules and glomerulus, and less Gb3 deposition in Fabry mice treated with this gene therapy than in mice given ERT. The α-gal A gene transfer significantly reduced the accumulation of Gb3 in the tubules and podocytes of the kidney. Electron microscopic analysis of the kidneys of Fabry mice also showed that gene therapy was more effective than ERT.</p> <p>Conclusions</p> <p>The rAAV2/8-hAGA mediated α-Gal A gene therapy provided improved efficiency over ERT in the Fabry disease mouse model. Furthermore, rAAV2/8-hAGA-mediated expression showed a greater effect in the kidney than ERT.</p
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