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51.
Wei Yang Xiaonan Xu Yang Li Yingzi Wang Ming Li Yong Wang Xinhua Ding Zhaohui Chu 《PloS one》2016,11(1)
Flavonoids are ubiquitous in the plant kingdom and have many diverse functions, including UV protection, auxin transport inhibition, allelopathy, flower coloring and insect resistance. Here we show that rutin, a proud member of the flavonoid family, could be functional as an activator to improve plant disease resistances. Three plant species pretreated with 2 mM rutin were found to enhance resistance to Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Pseudomonas syringae pv. tomato strain DC3000 in rice, tobacco and Arabidopsis thaliana respectively. While they were normally propagated on the cultural medium supplemented with 2 mM rutin for those pathogenic bacteria. The enhanced resistance was associated with primed expression of several pathogenesis-related genes. We also demonstrated that the rutin-mediated priming resistance was attenuated in npr1, eds1, eds5, pad4-1, ndr1 mutants, and NahG transgenic Arabidopsis plant, while not in either snc1-11, ein2-5 or jar1 mutants. We concluded that the rutin-priming defense signal was modulated by the salicylic acid (SA)-dependent pathway from an early stage upstream of NDR1 and EDS1. 相似文献
52.
We tried to establish compatible carbon content models of individual trees for a Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) plantation from Fujian province in southeast China. In general, compatibility requires that the sum of components equal the whole tree, meaning that the sum of percentages calculated from component equations should equal 100%. Thus, we used multiple approaches to simulate carbon content in boles, branches, foliage leaves, roots and the whole individual trees. The approaches included (i) single optimal fitting (SOF), (ii) nonlinear adjustment in proportion (NAP) and (iii) nonlinear seemingly unrelated regression (NSUR). These approaches were used in combination with variables relating diameter at breast height (D) and tree height (H), such as D, D2H, DH and D&H (where D&H means two separate variables in bivariate model). Power, exponential and polynomial functions were tested as well as a new general function model was proposed by this study. Weighted least squares regression models were employed to eliminate heteroscedasticity. Model performances were evaluated by using mean residuals, residual variance, mean square error and the determination coefficient. The results indicated that models with two dimensional variables (DH, D2H and D&H) were always superior to those with a single variable (D). The D&H variable combination was found to be the most useful predictor. Of all the approaches, SOF could establish a single optimal model separately, but there were deviations in estimating results due to existing incompatibilities, while NAP and NSUR could ensure predictions compatibility. Simultaneously, we found that the new general model had better accuracy than others. In conclusion, we recommend that the new general model be used to estimate carbon content for Chinese fir and considered for other vegetation types as well. 相似文献
53.
Mohan C. Pereira Monica Pianella Da Wei Anna Moshnikova Carlotta Marianecci Maria Carafa 《Molecular membrane biology》2016,33(3-5):51-63
Nanomedicine is becoming very popular over conventional methods due to the ability to tune physico-chemical properties of nano vectors, which are used for encapsulation of therapeutic and diagnostic agents. However, the success of nanomedicine primarily relies on how specifically and efficiently nanocarriers can target pathological sites to minimize undesirable side effects and enhance therapeutic efficacy. Here, we introduce a novel class of targeted nano drug delivery system, which can be used as an effective nano-theranostic for cancer. We formulated pH-sensitive niosomes (80–90?nm in diameter) using nonionic surfactants Span20 (43–45?mol%), cholesterol (50?mol%) and 5?mol% of pH (Low) insertion peptide (pHLIP) conjugated with DSPE lipids (DSPE-pHLIP) or hydrophobic fluorescent dye, pyrene, (Pyr-pHLIP). In coating of niosomes, pHLIP was used as an acidity sensitive targeting moiety. We have demonstrated that pHLIP coated niosomes sense the extracellular acidity of cancerous cells. Intravenous injection of fluorescently labeled (R18) pHLIP-coated niosomes into mice bearing tumors showed significant accumulation in tumors with minimal targeting of kidney, liver and muscles. Tumor-targeting niosomes coated with pHLIP exhibited 2–3 times higher tumor uptake compared to the non-targeted niosomes coated with PEG polymer. Long circulation time and uniform bio-distribution throughout the entire tumor make pHLIP-coated niosomes to be an attractive novel delivery system. 相似文献
54.
S-adenosylmethionine stimulates fatty acid metabolism-linked gene expression in porcine muscle satellite cells 总被引:2,自引:0,他引:2
Evidence indicates that both S-adenosylmethionine (SAMe) metabolism and intramuscular fat are associated with insulin resistance
and type II diabetes. However, it is still unknown whether SAMe have effects on intramuscular adipogenesis. The present study
investigated the roles of SAMe in the adipogenic differentiation of porcine muscle satellite cells. Cells isolated from neonatal
pig muscle were treated with different concentrations of SAMe (0, 0.5 and 1.0 mM) for 24 h, induced for a 9-day adipogenic
differentiation and were finally stained by oil red O staining. The adipocyte determination and differentiation factor-1 (ADD1)
and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA and protein were stimulated by SAMe treatment in a dose-dependent
manner. Lipoprotein lipase (LPL) mRNA and protein were enhanced in 1.0 mM treatment group, compared with the control. No significant
difference was observed in the intracellular lipid content among treatments. These results provide evidence that SAMe may
be associated with intramuscular adipogenesis and indicate a novel action of SAMe in fat metabolism. 相似文献
55.
Wei Zhang Nick Bansback Annelies Boonen Adam Young Amitabh Singh Aslam H Anis 《Arthritis research & therapy》2010,12(5):R177
Introduction
The Work Productivity and Activity Impairment (WPAI) questionnaire is a well validated instrument to measure impairments in work and activities. However, its validation among patients with rheumatoid arthritis (RA) has not been well established. The present study's purpose is to evaluate the construct validity of the WPAI-general health version among RA patients and its ability to differentiate between RA patients with varying health status. 相似文献56.
57.
58.
Zhi Xue Daniel Wei‐Jing Kwong Ling‐Wei Xue Qing Liu An‐Xin Hou Wai‐Kwok Wong 《化学与生物多样性》2009,6(7):1131-1143
Novel diselenide‐linked porphyrin dimers were synthesized under phase‐transfer catalysis conditions. The targeted compounds were characterized by 1H‐NMR, high‐resolution mass spectrometry, UV/VIS and fluorescence spectroscopies, redox‐potential measurements, and elemental analysis. The interaction of the title compounds with DNA was studied using UV/VIS, fluorescence, and circular dichroism (CD) spectroscopies. The relative rates of singlet‐oxygen production from the diselenide‐linked porphyrin dimers upon photoirradiation were also measured. 相似文献
59.
60.
Yu Zheng-Chao Lin Wei Zheng Xiao-Ting Chow Wah Soon Luo Yan-Na Cai Min-Ling Peng Chang-Lian 《Photosynthesis research》2021,149(1-2):41-55
Photosynthesis Research - Increasing amounts of experimental evidence show that anthocyanins provide physiological protection to plants under stress. However, the difference in photoprotection... 相似文献