Reverse effect of FOXC2 silencing on epithelial-mesenchymal transition induced by TGF-β1 in MCF-7 cells

AIM: To study the reverse effect of FOXC2 silencing on epithelial-mesenchymal transition (EMT) induced by transforming growth factor β1(TGF-β1) in MCF-7 cells. METHODS: Cultured MCF-7 cells were treated with TGF-β1 at concentration of 5 μg/L for 6 d. The cell morphological changes were observed under phase-contrast microscope. The changes of EMT-related marker proteins were assessed by immunofluorescence staining assay. TGF-β1-induced MCF-7 cells were transfected with FOXC2-siRNA mediated by recombinant lentivirus. In addition, the expression levels of FOXC2 and EMT-related marker proteins E-cadherin, claudin-1 and fibronectin-1 were also measured by RT-PCR and Western blotting. The invasion of MCF-7 cells was detected by Transwell assay. RESULTS: TGF-β1 induced the morphological alteration in MCF-7 cells from epithelial phenotype to mesenchymal phenotype,up-regulated the expression of mesenchymal marker fibronectin-1, and down-regulated the expression of epithelial markers E-cadherin and claudin-1. FOXC2 silencing reversed and restored the mesenchymal MCF-7 cells to epithelial phenotype and reduced the tumor invasion. CONCLUSION: EMT model induced by TGF-β1 in breast cancer MCF-7 cells is successfully established, which increases the invasion of MCF-7 cells. The effect of TGF-β1 is reversed by FOXC2-siRNA and the invasion of the cells is reduced.     

枸杞中高效氯氰菊酯的残留动态研究

为了评价高效氯氰菊酯在枸杞上使用后的残留动态,在宁夏、青海、新疆三地进行了高效氯氰菊酯在枸杞上的残留动态试验。结果表明：高效氯氰菊酯在枸杞中的残留消解完全符合一级反应动力学方程式,高效氯氰菊酯在枸杞鲜果上的半衰期为5.2~6.5天,高效氯氰菊酯在枸杞干果上的半衰期为4.8~8.8天。按推荐剂量施用的情况下,高效氯氰菊酯在枸杞中的残留为0.0108~0.460 mg/kg。高效氯氰菊酯在枸杞中最大残留限量（MRL值）推荐值为1 mg/kg。     

Environmental similarity is more important than distance in the community structuring processes of ammonia-oxidizing archaea in agricultural soils

Ammonia-oxidizing archaea(AOA) are important in converting ammonia into nitrate in soils. While many aspects of their community structure have been studied, the relative importance of stochastic versus deterministic processes has poorly been understood. We compared AOA communities across the North China Plain, targeting the amoA gene. A phylogenetic null modelling approach was used to calculate the beta nearest taxon index to quantify the influence of stochastic and deterministic processes. We f...     

Heritability of β-glucan, groat percentage, and crown rust resistance in two oat crosses

Summary Parent-offspring regression was used to estimate heritability for three traits (-glucan content, groat percentage, and resistance to crown rust (Puccinia coronata Cda. f. sp. avenae Eriks.) in oat (Avena sativa L.). The populations used were derived from two crosses, Nova x Marion QC and Sylva x Marion QC. Marion QC was used as a parent because other research had shown that it is relatively high in -glucan, a trait for which heritability had not previously been estimated. Nova and Sylva are similar in adaptation to Marion QC, and Sylva may be a source of general resistance to crown rust. Random F₅ plants were grown in a greenhouse, and their F₆ and F₇ progeny were grown in replicated field trials. Heritability estimates for the two grain quality traits were based on regression of F₆ values on F₅ values, F₇ values on F₆ values, and F₇ values on F₅ values. Heritability estimates for -glucan content were between 0.27 and 0.45. The highest estimate was the one based on the F₆ and F₇ generations of Sylva x Marion QC: 0.45, compared to estimates of 0.32 or less for earlier generations of the same cross, and to estimates of 0.35 or less for all generations of Nova x Marion QC. Heritability estimates for groat percentage were all between 0.23 and 0.32. The F₆ and F₇ generations were evaluated for resistance to crown rust resistance. The Sylva x Marion QC cross seemed to segregate for heritable resistance (h ²=0.31) but the Nova x Marion QC cross did not (h ²=0.07). Several lines from the Sylva x Marion QC cross had low symptoms in both the F₆ and F₇ generations. There were no strong genetic correlations among the traits.     

In Vitro Accessibility and Intake of β-Carotene From Cooked Green Leafy Vegetables and Their Estimated Contribution to Vitamin A Requirements

Provitamin A carotenoids from green leafy vegetables constitute a major dietary source of vitamin A in Tanzania. The efficiency of different vegetable preparations in contributing to the daily safe intake level of vitamin A for children was evaluated in the present study. The amount of bioaccessible (available for absorption) all-trans--carotene from green leafy vegetable dishes prepared either traditionally in households or with an improved method was estimated by an in vitro digestion method that simulates human digestion. The median vegetable portion size consumed by 34 children (2--12 years old) in the surveyed households was determined by weighing. The amount of all-trans--carotene available for absorption from the same type of vegetables cooked without oil by traditional or a modified method ranged from 5 to 12% and 4 to 15%, respectively. Vegetables cooked with modified method with oil had 2–5 times higher amount of in vitro accessible all-trans--carotene than vegetables cooked without oil. A median portion (84 g) of such a relish then provided 88–477% of the daily safe intake level of vitamin A, while portions cooked without oil only provided between 23 and 46%. In this study, a wide variation in all-trans--carotene content and bioaccessibility among studied green leaves was obtained. Still, to supply daily safe intake level of vitamin A for children from a median vegetable relish portion it is necessary to add oil in the preparation.     

Inhibition of N-Type Calcium Channels by Fluorophenoxyanilide Derivatives

A set of fluorophenoxyanilides, designed to be simplified analogues of previously reported ω-conotoxin GVIA mimetics, were prepared and tested for N-type calcium channel inhibition in a SH-SY5Y neuroblastoma FLIPR assay. N-type or Ca_v2.2 channel is a validated target for the treatment of refractory chronic pain. Despite being significantly less complex than the originally designed mimetics, up to a seven-fold improvement in activity was observed.     

Formation and chemical structures of acid-soluble lignin II: reaction of aromatic nuclei model compounds with xylan in the presence of a counterpart for condensation,and behavior of lignin model compounds with guaiacyl and syringyl nuclei in 72% sulfuric acid

To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl₃-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl₃-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl₃-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62