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51.
Hayley M Bennett Hoi Ping Mok Effrossyni Gkrania-Klotsas Isheng J Tsai Eleanor J Stanley Nagui M Antoun Avril Coghlan Bhavana Harsha Alessandra Traini Diogo M Ribeiro Sascha Steinbiss Sebastian B Lucas Kieren SJ Allinson Stephen J Price Thomas S Santarius Andrew J Carmichael Peter L Chiodini Nancy Holroyd Andrew F Dean Matthew Berriman 《Genome biology》2014,15(11)
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53.
Chien-Hsing Lin Ling-Hui Li Sheng-Feng Ho Tzu-Po Chuang Jer-Yuarn Wu Yuan-Tsong Chen Cathy SJ Fann 《BMC genetics》2008,9(1):1-9
Background
Winter migration of immature brown trout (Salmo trutta) into freshwater rivers has been hypothesized to result from physiologically stressful combinations of high salinity and low temperature in the sea.Results
We sampled brown trout from two Danish populations entering different saline conditions and quantified expression of the hsp70 and Na/K-ATPases α 1b genes following acclimation to freshwater and full-strength seawater at 2°C and 10°C. An interaction effect of low temperature and high salinity on expression of both hsp70 and Na/K-ATPase α 1b was found in trout from the river entering high saline conditions, while a temperature independent up-regulation of both genes in full-strength seawater was found for trout entering marine conditions with lower salinities.Conclusion
Overall our results support the hypothesis that physiologically stressful conditions in the sea drive sea-run brown trout into freshwater rivers in winter. However, our results also demonstrate intra-specific differences in expression of important stress and osmoregulative genes most likely reflecting adaptive differences between trout populations on a regional scale, thus strongly suggesting local adaptations driven by the local marine environment. 相似文献54.
All‐Nanomat Lithium‐Ion Batteries: A New Cell Architecture Platform for Ultrahigh Energy Density and Mechanical Flexibility 下载免费PDF全文
Ju‐Myung Kim Jeong A. Kim Seung‐Hyeok Kim In Sung Uhm Sung Joong Kang Guntae Kim Sun‐Young Lee Sun‐Hwa Yeon Sang‐Young Lee 《Liver Transplantation》2017,7(22)
The ongoing surge in demand for high‐energy/flexible rechargeable batteries relentlessly drives technological innovations in cell architecture as well as electrochemically active materials. Here, a new class of all‐nanomat lithium‐ion batteries (LIBs) based on 1D building element‐interweaved heteronanomat skeletons is demonstrated. Among various electrode materials, silicon (Si, for anode) and overlithiated layered oxide (OLO, for cathode) materials are chosen as model systems to explore feasibility of this new cell architecture and achieve unprecedented cell capacity. Nanomat electrodes, which are completely different from conventional slurry‐cast electrodes, are fabricated through concurrent electrospinning (for polymeric nanofibers) and electrospraying (for electrode materials/carbon nanotubes (CNTs)). Si (or rambutan‐shaped OLO/CNT composite) powders are compactly embedded in the spatially interweaved polymeric nanofiber/CNT heteromat skeletons that play a crucial role in constructing 3D‐bicontinuous ion/electron transport pathways and allow for removal of metallic foil current collectors. The nanomat Si anodes and nanomat OLO cathodes are assembled with nanomat Al2O3 separators, leading to the fabrication of all‐nanomat LIB full cells. Driven by the aforementioned structural/chemical uniqueness, the all‐nanomat full cell shows exceptional improvement in electrochemical performance (notably, cell‐based gravimetric energy density = 479 W h kgCell?1) and also mechanical deformability, which lie far beyond those achievable with conventional LIB technologies. 相似文献
55.
Purified inulinase (inulase, 2,1-β-d-fructan fructanohydrolase, EC 3.2.1.7) of Kluyveromyces fragilis has been immobilized on 2-aminoethyl-cellulose by treatment with 2% glutaraldehyde in 0.05 m phosphate buffer, pH 7.0, for 2 h at room temperature. The immobilized enzyme preparation had 39.3 units inulinase activity per gram dried matrix, with 53.4% recovery yield of activity, and showed good operational stability in the presence of substrate, inulin or the tuber extract of Jerusalem artichoke. Optimum pH and temperature were 5.5 and 45°C, respectively. In a batch reactor, the conversion was 90% () and 34 mg d-fructose per ml was produced from the artichoke tuber extract by the immobilized inulinase in 20 h. In column reactor packed with 28 ml immobilized enzyme, the following conditions were found to be optimal: height/diameter ratio of column, 10.3; space time, 3.8 h; temperature, 40°C. Operation under these conditions gave 90% conversion of a 7% inulin solution and the productivity was 102 mmol l?1 h?1. 相似文献
56.
57.
Ying-Chao Lin Ai-Ru Hsieh Ching-Lin Hsiao Shang-Jung Wu Hui-Min Wang Ie-Bin Lian Cathy SJ Fann 《Journal of biomedical science》2014,21(1)
Background
Genome-wide association studies have been successful in identifying common genetic variants for human diseases. However, much of the heritable variation associated with diseases such as Parkinson’s disease remains unknown suggesting that many more risk loci are yet to be identified. Rare variants have become important in disease association studies for explaining missing heritability. Methods for detecting this type of association require prior knowledge on candidate genes and combining variants within the region. These methods may suffer from power loss in situations with many neutral variants or causal variants with opposite effects.Results
We propose a method capable of scanning genetic variants to identify the region most likely harbouring disease gene with rare and/or common causal variants. Our method assigns a score at each individual variant based on our scoring system. It uses aggregate scores to identify the region with disease association. We evaluate performance by simulation based on 1000 Genomes sequencing data and compare with three commonly used methods. We use a Parkinson’s disease case–control dataset as a model to demonstrate the application of our method.Our method has better power than CMC and WSS and similar power to SKAT-O with well-controlled type I error under simulation based on 1000 Genomes sequencing data. In real data analysis, we confirm the association of α-synuclein gene (SNCA) with Parkinson’s disease (p = 0.005). We further identify association with hyaluronan synthase 2 (HAS2, p = 0.028) and kringle containing transmembrane protein 1 (KREMEN1, p = 0.006). KREMEN1 is associated with Wnt signalling pathway which has been shown to play an important role for neurodegeneration in Parkinson’s disease.Conclusions
Our method is time efficient and less sensitive to inclusion of neutral variants and direction effect of causal variants. It can narrow down a genomic region or a chromosome to a disease associated region. Using Parkinson’s disease as a model, our method not only confirms association for a known gene but also identifies two genes previously found by other studies. In spite of many existing methods, we conclude that our method serves as an efficient alternative for exploring genomic data containing both rare and common variants.Electronic supplementary material
The online version of this article (doi:10.1186/s12929-014-0088-9) contains supplementary material, which is available to authorized users. 相似文献58.
In this article, we report the synthesis of Na2Sr1‐x(PO4)F:Eux phosphor via a combustion method. The influence of different annealing temperatures on the photoluminescence properties was investigated. The phosphor was excited at both 254 and 393 nm. Na2Sr1‐x(PO4)F:Eux3+ phosphors emit strong orange and red color at 593 and 612 nm, respectively, under both excitation wavelengths. Na2Sr1‐x(PO4)F:Eux3+ phosphors annealed at 1050°C showed stronger emission intensity compared with 600, 900 and 1200°C. Moreover, Na2Sr1‐x(PO4)F:Eux3+ phosphor was found to be more intense when compared with commercial Y2O3:Eu3+ phosphor. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
59.
Seok SH Park JH Baek MW Lee HY Kim DJ Uhm HM Hong JJ Na YR Jin BH Ryu DY Park JH 《Journal of biotechnology》2006,126(3):406-413
Heat shock proteins (HSPs) play a central role in cell protection and repair upon stresses, such as that caused by heat and heavy metals. Copper sulfate inducibility of a pHhsp70 construct expressing the enhanced green fluorescent protein (EGFP) gene under the control of the exogenous human hsp70 promoter was tested in transfected CHSE 214 cells and transgenic zebrafish (Danio rerio). We developed a transient expression system, using mosaically transgenic zebrafish, which allows rapid analysis of transgenic expression. Transfected CHSE 214 cells which had been exposed to 250 nM and 2.5 microM copper sulfate for up to 24h showed increased EGFP expression in a dose-dependent manner. The 1.5 microM copper sulfate caused stronger EGFP fluorescence than the 1.0 microM copper sulfate in transgenic zebrafish. Most of the expression was spotty and was detected in the gills, dorsal and ventral retina, myotubes of the trunk, and skin epithelium. Transgenic zebrafish exposed to copper sulfate exhibited gross dysmorphogenesis, edema and trunk abnormalities, such as spinal lordosis, in vertebral development 5 days after fertilization. This transgenic zebrafish system was sensitive enough to detect copper sulfate at doses below the median lethal concentration (the LC50 was calculated to be 1.2 microM (95% confidence interval of 0.6-1.9 microM)). These results indicate that zebrafish could be useful transgenic biosensor systems for the detection of xenobiotic toxicants in the environment. 相似文献
60.
Tetracycline-inducible gene expression in nuclear transfer embryos derived from porcine fetal fibroblasts transformed with retrovirus vectors 总被引:2,自引:0,他引:2
Choi BR Koo BC Ahn KS Kwon MS Kim JH Cho SK Kim KM Kang JH Shim H Lee H Uhm SJ Lee HT Kim T 《Molecular reproduction and development》2006,73(10):1221-1229
A critical problem of transgenic livestock production is uncontrollable constitutive expression of the foreign gene, which usually results in serious physiological disturbances in transgenic animals. One of the best solutions for this problem may be use of controllable gene expression system. In this study, using retrovirus vectors designed to express the enhanced green fluorescent protein (EGFP) gene under the control of the tetracycline-inducible promoter, we examined whether the expression of the transgene could be controllable in fibroblast cells and nuclear transfer (NT) embryos of porcine. Transformed fibroblast cells were cultured in medium supplemented with or without doxycycline (a tetracycline analog) for 48 hr, and the induction efficiency was measured by comparing EGFP gene expression using epifluorescence microscopy and Western and Northern blot analyses. After the addition of doxycycline, EGFP expression increased up to 17-fold. The nuclei of transformed fibroblast cells were transferred into enucleated oocytes. Fluorescence emission data revealed strong EGFP gene expression in embryos cultured with doxycycline, but little or no expression in the absence of the antibiotic. Our results demonstrate the successful regulation of transgene expression in porcine nuclear transfer embryos, and support the application of an inducible expression system in transgenic pig production to solve the inherent problems of side-effects due to constitutive expression of the transgene. 相似文献