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971.
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Plant gene responses to frequency-specific sound signals   总被引:1,自引:0,他引:1  
We identified a set of sound-responsive genes in plants using a sound-treated subtractive library and demonstrated sound regulation through mRNA expression analyses. Under both light and dark conditions, sound up-regulated expression of rbcS and ald. These are also light-responsive genes and these results suggest that sound could represent an alternative to light as a gene regulator. Ald mRNA expression increased significantly with treatment at 125 and 250 Hz, whereas levels decreased significantly with treatment at 50 Hz, indicating a frequency-specific response. To investigate whether the ald promoter responds to sound, we generated transgenic rice plants harboring a chimeric gene comprising a fusion of the ald promoter and GUS reporter. In three independent transgenic lines treated with 50 or 250 Hz for 4 h, GUS mRNA expression was up-regulated at 250 Hz, but down-regulated at 50 Hz. Thus, the sound-responsive mRNA expression pattern observed for the ald promoter correlated closely with that of ald, suggesting that the 1,506 bp ald promoter is sound-responsive. Therefore, we propose that in transgenic plants, specific frequencies of sound treatment could be used to regulate the expression of any gene fused to the ald promoter.  相似文献   
973.
Cultures of water fern Azolla pinnata R. Br. exposed for 1 weekto either 30, 50 or 80 nl l-1 O3 showed significant reductionsin rates of growth and N2 fixation, and had fewer heterocysts.Although the levels of glutamine synthetase (GS) and glutamatedehydrogenase (GDH) activity were decreased by low concentrationsof O3 exposures (30 or 50 nl l-1), significant increases inlevels of the same enzymes were caused by higher concentrationsof O3 (80 nl l-1). Increased levels of total protein, polyamines(putrescine and spermidine), and the xanthophyll-cycle precursorof abscisic acid (ABA), violaxanthin, were also found with higherlevels of O3 (80 nl l-1). Levels of ABA itself were significantlyincreased by low level O3 fumigation (30 nl l-1) but significantlydecreased by exposure to 80 nl l-1 O3. This may indicate thathigher levels of atmospheric O3 inhibit the final stages ofABA biosynthesis from violaxanthin.Copyright 1994, 1999 AcademicPress Abscisic acid, nitrogen assimilation, nitrogen fixation, ozone pollution, polyamines, violaxanthin  相似文献   
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Passive and label-free isolation of viable target cells based on intrinsic biophysical cellular properties would allow for cost savings in applications where molecular biomarkers are known as well as potentially enable the separation of cells with little-to-no known molecular biomarkers. We have demonstrated the purification of adrenal cortical progenitor cells from digestions of murine adrenal glands utilizing hydrodynamic inertial lift forces that single cells and multicellular clusters differentially experience as they flow through a microchannel. Fluorescence staining, along with gene expression measurements, confirmed that populations of cells collected in different outlets were distinct from one another. Furthermore, primary murine cells processed through the device remained highly viable and could be cultured for 10 days in vitro. The proposed target cell isolation technique can provide a practical means to collect significant quantities of viable intact cells required to translate stem cell biology to regenerative medicine in a simple label-free manner.  相似文献   
978.
We investigated the effects of light emitting plasma (LEP) and red, blue, green, and white light emitting diode (LED) artificial light sources on plant growth characteristics and antioxidant activities in Astragalus membranaceus B. The highest germination rate (91.33 ± 2.08%) was produced by growth under red LED light. Root growth under LEP light was superior to that under the other light treatments. We measured antioxidant activity using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and determined the total phenol and flavonoid contents and tyrosinase inhibitory activity in response to the various light treatments. Antioxidant activities were 53.6% as the highest level of activity under LEP light. Growth under LEP light also produced the highest total phenolic and flavonoid contents of 36.05 and 5.94 mg/mL, respectively. Extracts from plants grown under LEP light caused the highest inhibition of tyrosinase activity with inhibition of 35.37, 61.87 and 65.49%, respectively, for extract concentrations of 100, 500, and 1000 μg/mL compared with other artificial light treatments. These results suggest that LEP light may be an important artificial light source for the enhancement of plant growth and biological activity and indicate the importance of further study of the use of LEP light sources for agricultural production.  相似文献   
979.
Given their important role in neuronal function, there has been an increasing focus on altered lipid levels in brain disorders. The effect of a high-fat (HF) diet on the lipid profiles of the cortex, hippocampus, hypothalamus, and olfactory bulb of the mouse brain was investigated using nanoflow ultrahigh pressure liquid chromatography-electrospray ionization-tandem mass spectrometry in the current study. For 8?weeks, two groups of 5-week-old mice were fed either an HF or normal diet (6 mice from each group analyzed as the F and N groups, respectively). The remaining mice in both groups then received a 4-week normal diet. Each group was then subdivided into two groups for another 4-week HF or normal diet. Quantitative analysis of 270 of the 359 lipids identified from brain tissue revealed that an HF diet significantly affected the brain lipidome in all brain regions that were analyzed. The HF diet significantly increased diacylglycerols, which play a role in insulin resistance in all regions that were analyzed. Although the HF diet increased most lipid species, the majority of phosphatidylserine species were decreased, while lysophosphatidylserine species, with the same acyl chain, were substantially increased. This result can be attributed to increased oxidative stress due to the HF diet. Further, weight-cycling (yo-yo effect) was found more critical for the perturbation of brain lipid profiles than weight gain without a preliminary experience of an HF diet. The present study reveals systematic alterations in brain lipid levels upon HF diet analyzed either by lipid class and molecular levels.  相似文献   
980.
Fish scales-derived collagen peptides (CPs) are characterized by their specific amino acid composition with a high concentration of glycine, proline and hydroxyproline. These amino acids have been known to exert beneficial effects on human skin. The aim of the present study was to examine the effects of collagen peptides obtained from fish scales on changes in periorbital wrinkles, facial skin hydration, and skin elasticity in healthy women aged 30–60 years. In the present randomized, placebo-controlled, double-blind trial, 71 subjects consumed a 20 mL beverage containing 3000 mg of CPs or placebo once per day over 12 weeks. Significant decreases in periorbital wrinkles (p?<?0.05) were observed in the treatment group after 12 weeks of CPs ingestion compared to the control group. This study also demonstrated a consistent trend of enhanced facial skin moisture (p?<?0.001) and skin elasticity (p?<?0.001) by dietary intake of CPs without any side effects or adverse events. These findings indicate that fish-derived CPs hold great promise as a natural supplement with cutaneous anti-aging properties.  相似文献   
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