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251.
Isocoumarin Derivatives from the Sponge‐Associated Fungus Peyronellaea glomerata with Antioxidant Activities 下载免费PDF全文
Chemical examination of the solid culture of the sponge‐associated fungus Peyronellaea glomerata led to the isolation of five new isocoumarins, namely peyroisocoumarins A – D ( 1 – 4 ) and isocitreoisocoumarinol ( 5 ), together with 13 known analogues ( 6 – 18 ). Their structures were determined on the basis of extensive spectroscopic analyses, including the modified Mosher's method for the configurational assignments. Peyroisocoumarins A and B were characterized by the presence of Cl‐atom at pentane chain, which were unusual in isocoumarin derivatives. The ARE reporter assay revealed that peyroisocoumarins A, B, and D exerted potent ARE activation in HepG2C8 cells, while the preliminary analyses of structure–activity relationship was discussed. 相似文献
252.
Shuen‐Fang Lo Ien‐Chie Wen Yi‐Lun Liu Ku‐Ting Chen Mirng‐Jier Jiang Ming‐Kuang Lin Meng‐Yen Rao Lin‐Chih Yu Tuan‐Hua David Ho Su‐May Yu 《Plant, cell & environment》2016,39(5):998-1013
Rice is an important crop and major model plant for monocot functional genomics studies. With the establishment of various genetic resources for rice genomics, the next challenge is to systematically assign functions to predicted genes in the rice genome. Compared with the robustness of genome sequencing and bioinformatics techniques, progress in understanding the function of rice genes has lagged, hampering the utilization of rice genes for cereal crop improvement. The use of transfer DNA (T‐DNA) insertional mutagenesis offers the advantage of uniform distribution throughout the rice genome, but preferentially in gene‐rich regions, resulting in direct gene knockout or activation of genes within 20–30 kb up‐ and downstream of the T‐DNA insertion site and high gene tagging efficiency. Here, we summarize the recent progress in functional genomics using the T‐DNA‐tagged rice mutant population. We also discuss important features of T‐DNA activation‐ and knockout‐tagging and promoter‐trapping of the rice genome in relation to mutant and candidate gene characterizations and how to more efficiently utilize rice mutant populations and datasets for high‐throughput functional genomics and phenomics studies by forward and reverse genetics approaches. These studies may facilitate the translation of rice functional genomics research to improvements of rice and other cereal crops. 相似文献
253.
ZnS:Mn nanoparticles were prepared by a chemical precipitation method and characterized by X‐ray diffraction (XRD), field emission gun scanning electron microscope (FEGSEM), and high resolution transmission electron microscopy (HRTEM). Capping agent (mercaptoethanol) concentrations used were 0 M, 0.005 M, 0.01 M, 0.015 M, 0.025 M, 0.040 M, and 0.060 M, and resulted in nanoparticles sizes of 2.98 nm, 2.9 nm, 2.8 nm, 2.7 nm, 2.61 nm, 2.2 nm and 2.1 nm, respectively. The thermoluminescence (TL) glow curve was recorded by heating the sample exposed to UV‐radiation, at a fixed heating rate 1°C sec–1. The TL intensity initially increased with temperature, attained a peak value Im for a particular temperature, and then decreased with further increase in temperature. The peak TL intensity increased with decreasing nanoparticle size, whereas the temperature corresponding to the peak TL intensity decreased slightly with reducing nanocrystal size. As a consequence of increase in surface‐to‐volume ratio and increased carrier recombination rates, the TL intensity increased with decreasing nanoparticle size. It was found that, whereas activation energy slightly decreased with decreasing nanoparticle size, the frequency factor decreased significantly with reduction in nanoparticle size. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
254.
《Cytokine》2016
BackgroundBiomarkers such as cytokines, chemokines, and soluble activation markers can be unstable when processing of blood is delayed. The stability of various biomarkers in serum and plasma was investigated when unprocessed blood samples were stored for up to 24 h at room and refrigerator temperature.MethodsBlood was collected from 16 healthy volunteers. Unprocessed serum, EDTA and heparinized blood was stored at room (20–25 °C) and refrigerator temperature (4–8 °C) for 0.5, 2, 4, 6, 8, and 24 h after collection before centrifugation and separation of serum and plasma. Samples were batch tested for various biomarkers using commercially available immunoassays. Statistically significant changes were determined using the generalized estimating equation.ResultsIFN-γ, sIL-2Rα, sTNF-RII and β2-microglobulin were stable in unprocessed serum, EDTA and heparinized blood samples stored at either room or refrigerator temperature for up to 24 h. IL-6, TNF-α, MIP-1β and RANTES were unstable in heparinized blood at room temperature; TNF-α, and MIP-1β were unstable in unprocessed serum at room temperature; IL-12 was unstable in unprocessed serum at refrigerator temperature; and neopterin was unstable in unprocessed EDTA blood at room temperature. IL-1ra was stable only in unprocessed serum at room temperature.ConclusionAll the biomarkers studied, with the exception of IL-1ra, were stable in unprocessed EDTA blood stored at refrigerator temperature for 24 h. This indicates that blood for these biomarkers should be collected in EDTA and if delays in processing are anticipated the unseparated blood should be stored at refrigerator temperature until processing. 相似文献
255.
《Cytokine》2016
Chronic systemic inflammation contributes to the development of adverse health conditions, yet the influence of fixed and modifiable risk factors on many serologic biomarkers of inflammation remains largely unknown. Serum concentrations of twenty-three biomarkers, including C-reactive protein (CRP), cytokines (CXCL11, CXCL8, CXCL10, CCL2, CCL13, CCL4, CCL17, CXCL13, IL-10, IL-12p70, IL-6, TNF-α, IL-2, IFN-γ, IL-1β, GM-CSF, BAFF), and soluble immune receptors (sCD14, sIL-2Rα, sCD27, sgp130, sTNF-R2) were measured longitudinally using multiplexed immunometric assays in 250 HIV-uninfected men followed in the Multicenter AIDS Cohort Study (1984–2009). Generalized gamma regression was used to determine the statistical significance of factors associated with each biomarker. After accounting for age, race, and education, and for analysis of multiple biomarkers, higher concentrations of specific individual biomarkers were significantly (P < 0.002) associated with hypertension, obesity, hepatitis C infection, stimulant use, and diabetes and lower concentrations with hypercholesterolemia. These associations should be taken into account in epidemiological studies of these biomarkers, and may provide potential targets for disease prevention and treatment. 相似文献
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258.
Ramon Velazquez Eric Ferreira Sara Knowles Chaya Fux Alexis Rodin Wendy Winslow Salvatore Oddo 《Aging cell》2019,18(6)
Currently, there are no effective therapies to ameliorate the pathological progression of Alzheimer's disease (AD). Evidence suggests that environmental factors may contribute to AD. Notably, dietary nutrients are suggested to play a key role in mediating mechanisms associated with brain function. Choline is a B‐like vitamin nutrient found in common foods that is important in various cell functions. It serves as a methyl donor and as a precursor for production of cell membranes. Choline is also the precursor for acetylcholine, a neurotransmitter which activates the alpha7 nicotinic acetylcholine receptor (α7nAchR), and also acts as an agonist for the Sigma‐1 R (σ1R). These receptors regulate CNS immune response, and their dysregulation contributes to AD pathogenesis. Here, we tested whether dietary choline supplementation throughout life reduces AD‐like pathology and rescues memory deficits in the APP/PS1 mouse model of AD. We exposed female APP/PS1 and NonTg mice to either a control choline (1.1 g/kg choline chloride) or a choline‐supplemented diet (5.0 g/kg choline chloride) from 2.5 to 10 months of age. Mice were tested in the Morris water maze to assess spatial memory followed by neuropathological evaluation. Lifelong choline supplementation significantly reduced amyloid‐β plaque load and improved spatial memory in APP/PS1 mice. Mechanistically, these changes were linked to a decrease of the amyloidogenic processing of APP, reductions in disease‐associated microglial activation, and a downregulation of the α7nAch and σ1 receptors. Our results demonstrate that lifelong choline supplementation produces profound benefits and suggest that simply modifying diet throughout life may reduce AD pathology. 相似文献
259.
Yue Liu Songhua Xu Xiuli Lian Yang Su Yuhuan Zhong Ruimin Lv 《Cell cycle (Georgetown, Tex.)》2019,18(4):437-451
Zygotic genome activation (ZGA) is one of the most critical events at the beginning of mammalian preimplantation embryo development (PED). The mechanisms underlying mouse ZGA remain unclear although it has been widely studied. In the present study, we identified that tricho-rhino-phalangeal syndrome 1 (TRPS1), an atypical GATA family member, is an important factor for ZGA in mouse PED. We found that the Trps1 mRNA level peaked at the one-cell stage while TRPS1 protein did so at the two/four-cell stage. Knockdown of Trps1 by the microinjection of Trps1 siRNA reduced the developmental rate of mouse preimplantation embryos by approximately 30%, and increased the expression of ZGA marker genes MuERV-L and Zscan4d via suppressing the expression of major histone markers H3K4me3 and H3K27me3. Furthermore, Trps1 knockdown decreased the expression of Sox2 but increased Oct4 expression. We conclude that TRPS1 may be indispensable for zygotic genome activation during mouse PED. 相似文献
260.