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51.
Effects of struvite formation and nitratation promotion on nitrogenous emissions such as NH3, N2O and NO during swine manure composting 总被引:4,自引:0,他引:4
To reduce nitrogenous emissions from composting, two different countermeasures were applied simultaneously in swine manure composting. One was forming struvite by adding Mg and P at the start of composting, and the other was to promote nitratation (nitrite being oxidized nitrate) by adding nitrite-oxidizing bacteria after the thermophilic phase of composting. In the laboratory- and mid-scale composting experiments, 25-43% of NH3, 52-80% of N2O and 96-99% of NO emissions were reduced. From the nitrogen balance, it was revealed that the struvite formation reduced not only NH3, but also other nitrogenous emissions except N2O. The amount of total nitrogen losses was reduced by 60% by the two combined countermeasures, against 51% by the struvite formation alone. However, the nitratation promotion dissolved struvite crystals due to the pH decline, diminishing the effect of struvite as a slow-release fertilizer. 相似文献
52.
Chonan T Wakasugi D Yamamoto D Yashiro M Oi T Tanaka H Ohoka-Sugita A Io F Koretsune H Hiratate A 《Bioorganic & medicinal chemistry》2011,19(5):1580-1593
Novel (4-piperidinyl)-piperazine derivatives were synthesized and evaluated as ACC1/2 non-selective inhibitors. Optimization of the substituents on the nitrogen of the piperidine ring led to the identification of the fluorine substituted tert-butoxycarbonyl group. Advanced analog, 1,1,1-trifluoro-2-methylpropan-2-yl 4-{4-[(2-amino-6-methyl-1-benzothiophen-3-yl)carbonyl]piperazin-1-yl}piperidine-1-carboxylate (12c) showed potent inhibitory activities in enzyme-assay and cell-based assays. Compound 12c also exhibited reduction of hepatic de novo fatty acid synthesis in rats after oral administration. 相似文献
53.
Ayumu Sugiura Ryo Yonashiro Toshifumi Fukuda Nobuko Matsushita Shun Nagashima Ryoko Inatome Shigeru Yanagi 《Mitochondrion》2011,11(1):139-146
Expansion of a polyglutamine tract in ataxin-3 (polyQ) causes Machado–Joseph disease, a late-onset neurodegenerative disorder characterized by ubiquitin-positive aggregate formation. Several lines of evidence demonstrate that polyQ also accumulates in mitochondria and causes mitochondrial dysfunction. To uncover the mechanism of mitochondrial quality-control via the ubiquitin–proteasome pathway, we investigated whether MITOL, a novel mitochondrial ubiquitin ligase localized in the mitochondrial outer membrane, is involved in the degradation of pathogenic ataxin-3 in mitochondria. In this study, we used N-terminal-truncated pathogenic ataxin-3 with a 71-glutamine repeat (ΔNAT-3Q71) and found that MITOL promoted ΔNAT-3Q71 degradation via the ubiquitin–proteasome pathway and attenuated mitochondrial accumulation of ΔNAT-3Q71. Conversely, MITOL knockdown induced an accumulation of detergent-insoluble ΔNAT-3Q71 with large aggregate formation, resulting in cytochrome c release and subsequent cell death. Thus, MITOL plays a protective role against polyQ toxicity, and thereby may be a potential target for therapy in polyQ diseases. Our findings indicate a protein quality-control mechanism at the mitochondrial outer membrane via a MITOL-mediated ubiquitin–proteasome pathway. 相似文献
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55.
Contributions of matrix and large protein genes of the measles virus edmonston strain to growth in cultured cells as revealed by recombinant viruses 下载免费PDF全文
The Edmonston strain of measles virus (MV) was obtained by sequential passages of the original isolate in various cultured cells. Although attenuated in vivo, it grows efficiently in most primate cell lines. Previous studies have revealed that MV tropism cannot be solely explained by the use of CD150 and/or CD46 as a cellular receptor. In order to evaluate the contributions of individual genes of the Edmonston strain to growth in cultured cells, we generated a series of recombinant viruses in which part of the genome of the clinical isolate IC-B (which uses CD150 as a receptor) was replaced with the corresponding sequences of the Edmonston strain. The recombinant virus possessing the Edmonston hemagglutinin (H) gene (encoding the receptor-binding protein) grew as efficiently in Vero cells as the Edmonston strain. Those viruses having either the matrix (M) or large (L) protein gene from the Edmonston strain could also replicate well in Vero cells, although they entered them at low efficiencies. P64S and E89K substitutions were responsible for the ability of the M protein to make virus grow efficiently in Vero cells, while the first half of the Edmonston L gene was important for better replication. Despite efficient growth in Vero cells, the recombinant viruses with these mutations had growth disadvantage in CD150-positive lymphoid B95a cells. Thus, not only the H gene but also the M and L genes contribute to efficient replication of the Edmonston strain in some cultured cells. 相似文献
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Isolation of human β-defensin-4 in lung tissue and its increase in lower respiratory tract infection
Shigehisa Yanagi Jun-ichi Ashitani Hiroshi Ishimoto Yukari Date Hiroshi Mukae Naoyoshi Chino Masamitsu Nakazato 《Respiratory research》2005,6(1):130
Background
Human β-defensin-4 (hBD-4), a new member of the β-defensin family, was discovered by an analysis of the genomic sequence. The objective of this study was to clarify hBD-4 expression in human lung tissue, along with the inducible expression in response to infectious stimuli, localization, and antimicrobial activities of hBD-4 peptides. We also investigated the participation of hBD-4 in chronic lower respiratory tract infections (LRTI) by measuring the concentrations of hBD-4 peptides in human bronchial epithelial lining fluid (ELF).Methods
The antimicrobial activity of synthetic hBD-4 peptides against E. coli and P. aeruginosa was measured by radial diffusion and colony count assays. We identified hBD-4 in homogenated human lung tissue by reverse-phase high-performance liquid chromatography coupled with a radioimmunoassay (RIA). Localization of hBD-4 was studied through immunohistochemical analysis (IHC). We investigated the effects of lipopolysaccharide (LPS) on hBD-4 expression and its release from small airway epithelial cells (SAEC). We collected ELF from patients with chronic LRTI using bronchoscopic microsampling to measure hBD-4 concentrations by RIA.Results
hBD-4 exhibited salt-sensitive antimicrobial activity against P. aeruginosa. We detected the presence of hBD-4 peptides in human lung tissue. IHC demonstrated the localization of hBD-4-producing cells in bronchial and bronchiolar epithelium. The levels of hBD-4 peptides released from LPS-treated SAECs were higher than those of untreated control cells. ELF hBD-4 was detectable in 4 of 6 patients with chronic LRTI, while the amounts in controls were all below the detectable level.Conclusion
This study suggested that hBD-4 plays a significant role in the innate immunity of the lower respiratory tract. 相似文献58.
Yanagi K Mizuno T Tsuyama T Tada S Iida Y Sugimoto A Eki T Enomoto T Hanaoka F 《The Journal of biological chemistry》2005,280(20):19689-19694
Cdt1 is an essential component for the assembly of a pre-replicative complex. Cdt1 activity is inhibited by geminin, which also participates in neural development and embryonic differentiation in many eukaryotes. Although Cdt1 homologues have been identified in organisms ranging from yeast to human, geminin homologues had not been described for Caenorhabditis elegans and fungi. Here, we identify the C. elegans geminin, GMN-1. Biochemical analysis reveals that GMN-1 associates with C. elegans CDT-1, the Hox protein NOB-1, and the Six protein CEH-32. GMN-1 inhibits not only the interaction between mouse Cdt1 and Mcm6 but also licensing activity in Xenopus egg extracts. RNA interference-mediated reduction of GMN-1 is associated with enlarged germ nuclei with aberrant nucleolar morphology, severely impaired gametogenesis, and chromosome bridging in intestinal cells. We conclude that the Cdt1-geminin system is conserved throughout metazoans and that geminin has evolved in these taxa to regulate proliferation and differentiation by directly interacting with Cdt1 and homeobox proteins. 相似文献
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Exudative age-related macular degeneration, characterized by choroidal neovascularization (CNV), is a major cause of visual loss. In this study, we examined the distribution of the polyion complex (PIC) micelle encapsulating FITC-P(Lys) in blood and in experimental CNV in rats to investigate whether PIC micelle can be used for treatment of CNV. We demonstrate that PIC micelle has long-circulating characteristics, accumulating to the CNV lesions and is retained in the lesion for as long as 168 h after intravenous administration. These results raise the possibility that PIC micelles can be used for achieving effective drug targeting to CNV. 相似文献