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41.
Won Noh Sang-Woo Kim Bae Dong-Won Jae-Yean Kim Hyeon-Su Ro 《Journal of microbiology (Seoul, Korea)》2010,48(2):253-256
Pleurotus eryngii was transformed via restriction enzyme-mediated integration. In order to construct the transformation plasmid, the enhanced
cyan fluorescent protein (ECFP) gene was ligated next to the gpd promoter of the plasmid pAN7-1. Transformation was facilitated via the heat treatment of a transformation mixture containing
1 μg of the HindIII-digested plasmid DNA and 106 mushroom protoplasts in 40% polyethyleneglycol solution, resulting in 10–40 hygromycin-resistant transformants. Successful
transformation was evidenced by PCR, Southern blot, and confocal fluorescence microscopic analyses on the selected transformants.
To date, this is the first report on the transformation of P. eryngii by REMI technique. 相似文献
42.
Autotrophic and heterotrophic respiration in needle fir and Quercus-dominated stands in a cool-temperate forest, central Korea 总被引:3,自引:0,他引:3
Na-yeon Lee Jin-Woo Koo Nam Jin Noh Joon Kim Yowhan Son 《Journal of plant research》2010,123(4):485-495
To investigate annual variation in soil respiration (R
S) and its components [autotrophic (R
A) and heterotrophic (R
H)] in relation to seasonal changes in soil temperature (ST) and soil water content (SWC) in an Abies holophylla stand (stand A) and a Quercus-dominated stand (stand Q), we set up trenched plots and measured R
S, ST and SWC for 2 years. The mean annual rate of R
S was 436 mg CO2 m−2 h−1, ranging from 76 to 1,170 mg CO2 m−2 h−1, in stand A and 376 mg CO2 m−2 h−1, ranging from 82 to 1,133 mg CO2 m−2 h−1, in stand Q. A significant relationship between R
S and its components and ST was observed over the 2 years in both stands, whereas a significant correlation between R
A and SWC was detected only in stand Q. On average over the 2 years, R
A accounted for approximately 34% (range 17–67%) and 31% (15–82%) of the variation in R
S in stands A and Q, respectively. Our results suggested that vegetation type did not significantly affect the annual mean
contributions of R
A or R
H, but did affect the pattern of seasonal change in the contribution of R
A to R
S. 相似文献
43.
Nam Jin Noh Yowhan Son Sue Kyoung Lee Tae Kyung Yoon Kyung Won Seo Choonsig Kim Woo-Kyun Lee Sang Won Bae Jaehong Hwang 《Journal of plant research》2010,123(4):411-419
We investigated the influence of stand density [938 tree ha−1 for high stand density (HD), 600 tree ha−1 for medium stand density (MD), and 375 tree ha−1 for low stand density (LD)] on soil CO2 efflux (R
S) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R
S measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature
(ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R
S (t C ha−1 year−1) and leaf litterfall (t C ha−1 year−1) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In
addition, R
S was correlated with ST (R
2 = 0.77–0.80, P < 0.001) and SWC (R
2 = 0.31–0.35, P < 0.001). It appeared that stand density influenced R
S via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R
2 = 0.71), TBCA (R
2 = 0.64–0.87), and total soil N contents in 2007 (R
2 = 0.94) explained a significant amount of the variance in R
S (P < 0.01). The current study showed that stand density is one of the key factors influencing R
S due to the changing biophysical and environmental factors in P. densiflora. 相似文献
44.
David R. Thomas Azis Araffin M.Noh Hj Jalil Bob C.S. Yong Robert J. Cooke Clifford Wood 《Phytochemistry》1981,20(6):1241-1244
Carnitine increases chlorophyll production in greening barley leaves. [Methyl-14C]carnitine fed to greening leaves was not utilized as a carbon sou 相似文献
45.
46.
We investigated the protective activity of radicicol, an antifungal antibiotic, against inflammation-induced neurotoxicity in neuron-glia cultures. Radicicol potently prevented the loss of neuronal cell bodies and neurites from LPS/IFN-gamma-induced neurotoxicity in rat cortical neuron-glia cultures with an EC(50) value of 0.09 microM. Radicicol inhibited the LPS/IFN-gamma-induced expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO) in microglia. Additionally, radicicol decreased the LPS/IFN-gamma-induced release of tumor necrosis factor-alpha (TNF-alpha) in the cultures. The inhibitory potency of radicicol against the production of NO and TNF-alpha was well correlated with the protection of neurons. These results suggest that the protective effect of radicicol against LPS/IFN-gamma-induced neuronal cell death in neuron-glia cultures is mediated via the inhibition of TNF-alpha release, as well as the suppression of iNOS expression in microglia. 相似文献
47.
Lee SC Mietchen D Cho JH Kim YS Kim C Hong KS Lee C Kang D Lee W Cheong C 《Differentiation; research in biological diversity》2007,75(1):84-92
Differentiation inside a developing embryo can be observed by a variety of optical methods but hardly so in opaque organisms. Embryos of the frog Xenopus laevis--a popular model system--belong to the latter category and, for this reason, are predominantly being investigated by means of physical sectioning. Magnetic resonance imaging (MRI) is a noninvasive method independent of the optical opaqueness of the object. Starting out from clinical diagnostics, the technique has now developed into a branch of microscopy--MR microscopy--that provides spatial resolutions of tens of microns for small biological objects. Nondestructive three-dimensional images of various embryos have been obtained using this technique. They were, however, usually acquired by long scans of fixed embryos. Previously reported in vivo studies did not cover the very early embryonic stages, mainly for sensitivity reasons. Here, by applying high field MR microscopy to the X. laevis system, we achieved the temporal and spatial resolution required for observing subcellular dynamics during early cell divisions in vivo. We present image series of dividing cells and nuclei and of the whole embryonic development from the zygote onto the hatching of the tadpole. Additionally, biomechanical analyses from successive MR images are introduced. These results demonstrate that MR microscopy can provide unique contributions to investigations of differentiating cells and tissues in vivo. 相似文献
48.
Green tea as inhibitor of the intestinal absorption of lipids: potential mechanism for its lipid-lowering effect 总被引:2,自引:0,他引:2
Animal and epidemiological studies suggest that green tea catechins may reduce the risk of cardiovascular diseases [e.g., coronary heart disease (CHD)]. The health benefit of green tea has been attributed to its antioxidant and anti-inflammatory properties; however, considerable evidence suggests that green tea and its catechins may reduce the risk of CHD by lowering the plasma levels of cholesterol and triglyceride. Although the mechanism underlying such effect of green tea is yet to be determined, it is evident from in vitro and in vivo studies that green tea or catechins inhibit the intestinal absorption of dietary lipids. Studies in vitro indicate that green tea catechins, particularly (-)-epigallocatechin gallate, interfere with the emulsification, digestion, and micellar solubilization of lipids, critical steps involved in the intestinal absorption of dietary fat, cholesterol, and other lipids. Based on the observations, it is likely that green tea or its catechins lower the absorption and tissue accumulation of other lipophilic organic compounds. The available information strongly suggests that green tea or its catechins may be used as safe and effective lipid-lowering therapeutic agents. 相似文献
49.
50.
Min BW Cho YN Song MJ Noh TK Kim BK Chae WK Park YS Choi YD Harn CH 《Plant cell reports》2007,26(3):337-344
A mannose selection system was adapted for use in the Agrobacterium-mediated transformation of Chinese cabbage. This system makes use of the pmi gene that encodes phosphomannose isomerase, which converts mannose-6-phosphate to fructose-6-phosphate. Hypocotyl explants
from 4–5-day-old seedlings of Chinese cabbage inbred lines were pre-cultured for 2–3 days and then infected with Agrobacterium. Two genes (l-guluno-γ-lactone oxidase, GLOase, and jasmonic methyl transferase, JMT) were transformed into Chinese cabbage using the transformation procedure developed in this study. We found that supplementing
the media with 7 g l−1 mannose and 2% sucrose provides the necessary conditions for the selection of transformed plants from nontransformed plants.
The transformation rates were 1.4% for GLOase and 3.0% for JMT, respectively. The Southern blot analysis revealed that several independent transformants (T
0) were obtained from each transgene. Three different inbred lines were transformed, and most of the T
1 plants had normal phenotypes. The transformation method presented here for Chinese cabbage using mannose selection is efficient
and reproducible, and it can be useful to introduce a desirable gene(s) into commercially useful inbred lines of Chinese cabbage. 相似文献