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941.
942.
Tetsuya Tanaka Md. Morshedur Rahman Banzragch Battur Damdinsuren Boldbaatar Min Liao Rika Umemiya-Shirafuji Xuenan Xuan Kozo Fujisaki 《In vitro cellular & developmental biology. Animal》2010,46(6):560-565
Human defensins play a fundamental role in the initiation of innate immune responses to some microbial pathogens. In this
paper, we show that human α-defensin-5 displays a parasiticidal role against Toxoplasma gondii, the causative agent of toxoplasmosis. Exposure of the tachyzoite form of T. gondii to defensin induced aggregation and significantly reduced parasite viability in a concentration-dependent peptide. Pre-incubation
of tachyzoites with human α-defensin-5 followed by exposure to a mouse embryonal cell line (NIH/3T3) significantly reduced
T. gondii infection in these cells. Thus, human α-defensin-5 is an innate immune molecule that causes severe toxocity to T. gondii and plays an important role in reducing cellular infection. This is the first report showing that human α-defensin-5 causes
aggregation, leading to Toxoplasma destruction. 相似文献
943.
Shu‐Jyuan Yang Szu‐Min Chang Kun‐Che Tsai Wen‐Shiang Chen Feng‐Huei Lin Ming‐Jium Shieh 《The journal of gene medicine》2010,12(2):168-179
Background
Gene therapy has been used to treat a variety of health problems, but transfection inefficiency and the lack of safe vectors have limited clinical progress. Fabrication of a vector that is safe and has high transfection efficiency is crucial for the development of successful gene therapy. The present study aimed to synthesize chitosan‐alginate nanoparticles that can be used as carriers of the pAcGFP1‐C1 plasmid and to use these nanoparticles with an ultrasound protocol to achieve high efficiency gene transfection.Methods
Chitosan was complexed with alginate and the pAcGFP1‐C1 plasmid at different charge ratios to create chitosan‐alginate‐DNA nanoparticles (CADNs). The average particle size and loading efficiency were measured. Plasmid DNA retardation and integrity were analysed on 1% agarose gels. The effect of CADNs and ultrasound on the efficiency of transfection of cells and subcutaneous tumors was evaluated.Results
In the CADNs, the average size of incorporated plasmid DNA was 600–650 nm and the loading efficiency was greater than 90%. On the basis of the results of the plasmid DNA protection test, CADNs could protect the transgene from DNase I degradation. The transgene product expression could be enhanced efficiently if cells or tumor tissues were first given CADNs and then treated with ultrasound.Conclusions
The use of CADNs combined with an ultrasound regimen is a promising method for safe and effective gene therapy. Copyright © 2009 John Wiley & Sons, Ltd.944.
Park IS Park JU Seo MJ Kim MJ Lee HH Kim SR Kang BW Choi YH Joo WH Jeong YK 《Journal of microbiology (Seoul, Korea)》2010,48(6):836-841
A fibrinolytic enzyme of the mushroom, Schizophyllum commune was purified with chromatographic methods, including a DEAE-Sephadex A-50 ion-exchange column and gel filtrations with Sephadex
G-75 and Sephadex G-50 columns. The analysis of fibrin-zymography and SDS-PAGE showed that the enzyme was a monomeric subunit
that was estimated to be approximately 17 kDa in size. The fibrinolytic activity of the enzyme in plasminogen-rich and plasminogen-free
fibrin plates was 1.25 and 0.44 U/ml, respectively. The N-terminal amino acid sequence of the purified enzyme was identified
as HYNIXNSWSSFID, which was highly distinguished from known fibrinolytic enzymes. The relative activity of the purified enzyme
with an addition of 5 mM EDTA, Phosphoramidon, and Bestatin was about 76, 64, and 52%, respectively, indicating that it is
a metalloprotease. The optimum temperature for the purified enzyme was approximately 45°C, and over 87% of the enzymatic activity
was maintained as a stable state in a pH range from 4.0 to 6.0. Therefore, our results suggest that the potential thrombolytic
agent from S. commune is a unique type of fibrinolytic enzyme. 相似文献
945.
This paper describes the development of a two-dimensional, spatially distributed model to simulate coupled hydrologic and phosphorus (P) biogeochemical processes in a 147-ha cell of a 1544-ha stormwater treatment wetland designed to help protect the greater Everglades, FL, USA. The model was used to assess the effects of a suite of feasible management alternatives on the long-term ability of the wetland to sustain total P (TP) removal. The spatial and temporal dynamics of TP retention were simulated under historical (1995–2000) conditions, and under assumptions of removal of short-circuiting channels and ditches, changes in external hydraulic and TP loading, and long-term (>20 years) impacts on soil and water column TP dynamics under current and reduced load conditions. Internal hydrology and transport processes were calibrated against measured tracer concentrations, and subsequently validated against outflow discharge and spatial chloride concentration data. Cycling of P was simulated as first-order uptake and release, with different uptake coefficients for open water/sparse submerged aquatic vegetation (SAV) areas (0.2 day?1) and dense SAV areas (0.4 day?1), and a much lower, uniform release coefficient (1.97 × 10?4 day?1). The calibration and validation of the P model showed good agreement with field measurements of water column TP concentrations measured at the wetland outlet (calibration RMSE = 10.5 μg L?1; validation RMSE = 15.6 μg L?1). Under simulated conditions of preferential channels eliminated, average annual TP treatment effectiveness increased by 25%. When inflow TP loads were assumed to be eliminated after 6 years of loading, the release of accumulated soil P sustained predicted annual average outlet concentrations above 6.7 μg L?1 for 18 years, decreasing at a rate of 0.16 μg L?1 yr?1. Sensitivity analyses indicate that the most critical model input factors include flow resistance parameters, initial soil TP content, and P cycling parameters compared to initial water level, initial TP concentration in water column, ET and transport parameters. 相似文献
946.
J. Geppert Y. Min M. Neville C. Lowy K. Ghebremeskel 《Prostaglandins, leukotrienes, and essential fatty acids》2010,82(1):51-56
Previous studies suggested that women synthesise docosahexaenoic acid (DHA) more efficiently from their precursors than men. This study investigated the relationship between diet, platelet phospholipids fatty acids and gender. Dietary intake and platelet phosphatidyl-choline (PC) and phosphatidylethanolamine (PE) fatty acids were determined in Caucasian 40 men and 34 women. Absolute and %energy intakes of arachidonic acid (AA), eicosapentaenoic acid (EPA), and DHA, and the ratios of total n-6/n-3 PUFA and linoleic/alpha-linolenic acids did not differ between the sexes. However, women had higher DHA in PC (1.19 vs 1.05 wt%, p<0.05) and PE (3.62 vs 3.21 wt%, p<0.05) than men. Also EPA (1.10 vs 0.93 wt%, p<0.05) was higher in women's PE. Conversely, men had elevated AA and total n-6 fatty acids in PC. The higher platelet DHA levels and lower platelet AA/EPA and AA/DHA ratios in women of child-bearing age compared with men, may lead to less platelet aggregation and vaso-occlusion. 相似文献
947.
Jongrae Kim Min Kyung Kong Sang Yup Lee Pyung Cheon Lee 《World journal of microbiology & biotechnology》2010,26(12):2231-2239
The effects of three phosphoenolpyruvate (PEP)-dependent PTS carbon sources (glucose, mannose and maltose) and three non-PTS
carbon sources (glycerol, galactose, and lactose) on the formation of four carotenoids with diverse structures and on the
cell growth of the recombinant Escherichia coli were investigated. The biosynthetic pathways of four carotenoids, C30 diapolycopene, C30 diapotorulene, C40 lycopene, and C40 beta-carotene, were engineered in E. coli. The resulting E. coli cells were grown in a mineral medium supplemented with each of the six carbon sources. Among the six carbon sources, non-PTS
glycerol showed the highest performance in production of all four carotenoid structures, whereas PTS glucose showed the lowest
performance. Based on the conversion yield, carotenoid-producing capability, and the cell density, we found that there was
no close correlation between PTS and non-PTS transport mechanism and carotenoid formations in E. coli. 相似文献
948.
Xuwu Sun Min Ouyang Jinkui Guo Jinfang Ma Congming Lu Zach Adam Lixin Zhang 《The Plant journal : for cell and molecular biology》2010,62(2):240-249
DegP proteases have been shown to possess both chaperone and protease activities. The proteolytic activities of chloroplast DegP‐like proteases have been well documented. However, whether chloroplast Deg proteases also have chaperone activities has remained unknown. Here we show that chloroplast Deg1 also has chaperone activities, like its Escherichia coli ortholog DegP. Transgenic plants with reduced levels of Deg1 accumulated normal levels of different subunits of the major photosynthetic protein complexes, but their levels of photosystem‐II (PSII) dimers and supercomplexes were reduced. In vivo pulse‐chase protein labeling experiments showed that the assembly of newly synthesized proteins into PSII dimers and supercomplexes was impaired, although the synthesis rate of chloroplast proteins was unaffected in the transgenic lines. Protein overlay assays provided direct evidence that Deg1 interacts with the PSII reaction center protein D2. These results suggest that Deg1 assists the assembly of the PSII complex, probably through interaction with the PSII reaction center D2 protein. 相似文献
949.
Lin He Fan He Huichang Bi Jiankang Li Su Zeng Hai-Bin Luo Min Huang 《Bioorganic & medicinal chemistry letters》2010,20(20):6008-6012
Our kinetics studies demonstrated that the nature product chrysin exhibited a high inhibitory affinity of 54 nM towards human cytochrome P450 1A2 and was comparable to α-naphthoflavone (49 nM), whereas it represented a moderate affinity of 5225 nM against human cytochrome P450 2C9. However, it remains unclear how this inhibitor selectively binds 1A2. To better understand the isoform selectivity of chrysin, molecular docking and molecular dynamics simulations were performed. Chrysin formed a strong H-bond with Asp313 of 1A2. The stacking interactions with Phe226 also contributed to its tight binding to 1A2. The larger and much more open active site architectures of 2C9 may explain the weaker inhibitory affinity of chrysin towards 2C9. The predicted binding free energies suggest that chrysin preferred 1A2 (ΔGbind, pred = ?23.11 kcal/mol) to 2C9 (?20.41 kcal/mol). Additionally, the present work revealed that 7-hydroxy-flavone bound to 1A2 in a similar pattern as chrysin and represented a slightly less negative predicted binding free energy, which was further validated by our kinetics analysis (IC50 = 240 nM). Results of the study can provide insight for designing novel isoform-selective 1A2 inhibitors. 相似文献
950.
The nucleus encounters other organelles as well as high cytoplasmic pressures during its migration within the cell. A new study describes how the action of kinesin and dynein motors is coordinated at the nuclear envelope to rock and roll the nucleus in Caenorhabditis elegans. 相似文献