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31.
Yuanshan Yao Qingwang Hua Yinjie Zhou 《Biochemical and biophysical research communications》2019,508(1):37-45
Recently, circular RNAs (circRNAs) are identified as a novel class of noncoding RNAs playing important roles in human malignant tumors. However, the regulatory function of circRNA in lung adenocarcinoma (LUAD) is still largely unknown. Present study aimed to explore the role of circ_0006427 in LUAD progression. Firstly, the downregulation of circ_0006427 in LUAD tissues and cell lines was revealed by microarray analysis and qRT-PCR analysis. And we also confirmed the circ_0006427 as a prognostic target in LUAD patients. Functionally, overexpression of circ_0006427 effectively suppressed cell proliferation, migration and invasion. Mechanistically, circ_0006427 was found to be predominantly located in the cytoplasm of LUCA cell, and was further revealed to positively regulate DKK1 in LUAD by sponging miR-6783–3p. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis and western blot analysis revealed that circ_0006427 inactivated Wnt/β-catenin signaling pathway by upregulating DKK1. At last, rescue assays proved the function of circ_0006427/miR-6783–3p/DKK1 axis in LUAD progression. In conclusion, our study revealed that circ_0006427 suppressed lung adenocarcinoma progression through regulating miR-6783–3p/DKK1 axis. 相似文献
32.
The use of entomopathogenic nematodes on cabbage leaves against larvae of the diamondback moth (DBM) Plutella xylostella requires the addition of formulation adjuvants to achieve satisfying control. Without adjuvants nematodes settle in the tank mix of backpack sprayers causing uneven distribution. The polymers arabic and guar gum, alginate and xanthan were used in concentrations between 0.05 and 0.3% to retard sedimentation of Steinernema carpocapsae. Arabic gum had no effect, guar gum prevented sedimentation at 0.3% but the effect dropped significantly at lower concentration. At 0.05%, xanthan prevented nematode sedimentation better than alginate. Deposition of nematodes on the leaves was significantly increased by the addition of any of the polymers. Spraying nematodes on leaves with an inclination of 45° without the addition of any formulation resulted in 70% run-off. Adding 0.2% alginate or xanthan reduced the losses to <20%. The use of a surfactant–polymer formulation significantly reduced defoliation by DBM larvae. Visual examinations provided evidence that nematodes are not ingested by DBM larvae. Invasion of S. carpocapsae is an active process via the anus. The function of the formulation is not to prolong nematode survival, but to provide environmental conditions which enable rapid invasion of the nematodes. Nematode performance was improved by selection of the best surfactant in combination with xanthan and by optimisation of the concentrations of the surfactant Rimulgan® and the polymer xanthan. The best control results were achieved with Rimulgan® at 0.3% together with 0.3% xanthan, causing DBM mortality of >90% at 80% relative humidity and >70% at 60%. The formulation lowered the LC50 from 12 to 1 nematode/larva. The viscosity of the surfactant–polymer formulations correlated well with nematode efficacy, prevention of sedimentation and adherence to the leave. This physical parameter can therefore be recommended for improvement of nematode formulations to be used for foliar application against DBM. 相似文献
33.
Fine root distribution of trees and understory in mature stands of maritime pine (Pinus pinaster) on dry and humid sites 总被引:2,自引:0,他引:2
Maritime pine (Pinus pinaster) is the main tree cropping species in the Landes of Gascogne forest range in south western France. Soils are nutrient poor, sandy podzosols and site fertility is determined essentially by organic matter content and depth of water table, which is known to limit root growth. We hypothesised, with an ultimate goal of constructing a nutrient uptake model applicable to this region, that the organic top horizons together with the depth of the water table should be the most important parameters related to fine root distribution and presence of associated mycorrhiza. To test this hypothesis, we compared two adult Pinus pinaster stands, contrasting in depth of water table and soil fertility and evaluated fine roots (diameter ≤2 mm) of understory species and fine roots and ectomycorrhizal morphotypes of Pinus pinaster down to 1.2 m, using a soil corer approach. Total fine root biomass of Pinus pinaster was not significantly different between both sites (3.6 and 4.5 t ha−1 for the humid, respectively, dry site), but root distribution was significantly shallower and root diameter increased more with depth at the humid site, presumably due to more adverse soil conditions as related to the presence of a hardpan, higher amount of aluminium oxides and / or anoxia. Fine roots of Pinus pinaster represented only about 30% of total fine root biomass and 15% of total fine root length, suggesting that the understory species cannot be ignored with regards to competition for mineral nutrients and water. A comparison of the ectomycorrhizal morphotypes showed that the humid site could be characterised by a very large proportion of contact exploration types, thought to be more relevant in accessing organic nutrient sources, whereas the dry site had a significantly higher proportion of both long-distance and short-distance exploration types, the latter of which was thought to be more resistant to short-term drought periods. These results partly confirm our hypothesis on root distribution as related to the presence of soil mineral nutrients (i.e. in organic matter), point out the potential role of understory plant species and ectomycorrhizal symbiosis and are a valuable step in building a site-specific nutrient uptake model. 相似文献
34.
Day–night cycle is the main zeitgeber (time giver) for biological circadian rhythms. Recently, it was suggested that natural diurnal geomagnetic variation may also be utilized by organisms for the synchronization of these rhythms. In this study, life-history traits in Daphnia magna were evaluated after short-term and multigenerational exposure to 16 h day/8 h night cycle, 32 h day/16 h night cycle, diurnal geomagnetic variation of 24 h, simulated magnetic variation of 48 h, and combinations of these conditions. With short-term exposure, the lighting mode substantially influenced the brood to brood period and the lifespan in daphnids. The brood to brood period, brood size, and body length of crustaceans similarly depended on the lighting mode during the multigenerational exposure. At the same time, an interaction of lighting mode and magnetic variations affected to a lesser extent brood to brood period, brood size, and newborn's body length. The influence of simulated diurnal variation on life-history traits in daphnids appeared distinctly as effects of synchronization between periods of lighting mode and magnetic variations during the multigenerational exposure. Newborn's body length significantly depended on the lighting regime when the periods of both studied zeitgebers were unsynchronized, or on the interaction of light regime with magnetic variations when the periods were synchronized. These results confirm the hypothesis that diurnal geomagnetic variation is an additional zeitgeber for biological circadian rhythms. Possible mechanisms for these observed effects are discussed. Bioelectromagnetics. © 2020 Bioelectromagnetics Society 相似文献
35.
《Bioorganic & medicinal chemistry letters》2014,24(10):2329-2333
The fruits of Cudrania tricuspidata (Carr.) Bur. (Moraceae) significantly inhibited pancreatic lipase, which plays a key role in fat absorption. Optimization of extraction conditions with minimum pancreatic lipase activity and maximum yield was determined using response surface methodology with three-level-three-factor Box–Behnken design (BBD). Regression analysis showed a good fit of the experimental data and the optimal condition was obtained as ethanol concentration, 74.5%; temperature 61.9 °C and extraction time, 13.5 h. The pancreatic lipase activity and extraction yield under optimal conditions were found to be 65.5% and 54.0%, respectively, which were well matched with the predicted value of 65.8% and 47.1%. Further fractionation of C. tricuspidata extract resulted in the isolation of compound 1, which was identified as 5,7,4′-trihydroxy-6,8-diprenylisoflavone. It inhibited pancreatic lipase activity with IC50 value of 65.0 μM. HPLC analysis suggested positive correlation between pancreatic lipase inhibition and 5,7,4′-trihydroxy-6,8-diprenylisoflavone of C. tricuspidata fruits. 相似文献
36.
Potassium iodate (KIO3) and potassium iodide (KI) are the major salt iodization agents used worldwide. Unlike iodide (I−), iodate (IO3−) should be reduced to I− before it can be effectively used by the thyroid. In this study, we developed a new method for analyzing IO3− and I− in tissue homogenates using high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC–ICP-MS). We further applied the method to demonstrate the KIO3 reduction process by tissues in vitro. The effects of KIO3 on the total antioxidative activity (TAA) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) were also investigated here. Finally, we found that IO3− can be reduced to I− by tissue homogenates and IO3− irreversibly decreases the antioxidant capability of tissues. Our studies suggest that KIO3 might have a big effect on the redox balance of tissue and would further result in oxidative stress of organisms. 相似文献
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As we confront the current environmental crisis, determining the biophysical base (e.g., materials, energy, land, and water) of nations has become paramount. With advanced economies benefiting from the import of resource-intensive primary goods originating from poorer parts of the world, especially emerging nations, these are dilapidating their natural capital. Brazil is one of such emerging economies, whose mining and farming activities, propping up its export-led economic growth, exert great pressure on the environment. In particular, farming has been shown to have one of the world's greatest environmental impacts, especially as a consequence of land use associated with cattle ranching. Since a nation-wide evaluation of land-use types across the whole sectorial spectrum of the country's economy is still lacking, we used the most recently available Input–Output Economic Model for Brazil and the Ecological Footprint method to identify those economic sectors with the greatest potential for appropriating portions of the natural world.Our results show that: (i) the biggest chunk of Brazil's Ecological Footprint is due to its Carbon Footprint and, in particular, emissions from cattle; (ii) only a few economic sectors exhibit high Ecological Footprint values, chiefly those belonging to livestock farming and energy production based on fossil fuels; (iii) excluding the soybeans and slaughter sectors, export-oriented sectors have below-average Ecological Footprint values; and (iv) the percentage of Brazil's Ecological Footprint due to household consumption (excluding imports) is three times bigger than that attributable to exports, with sectors belonging to livestock farming contributing the most to such disparity.These results underscore that the environmental impact of the Brazilian economy can be drastically reduced by tackling the emission-intensive production processes of a few sectors only and disincentivizing the domestic consumption of a narrow range of products, especially with respect to the livestock segment. 相似文献