谷氨酰胺合成酶抑制剂对烤烟烘烤特性的影响

以烤烟品种‘K326’叶片为材料,在达到工艺成熟期前7d分别用质量分数为0.005%和0.01%的谷氨酰胺合成酶(GS)抑制剂4-[羟基(甲基)膦酰基]-D/L-高丙氨酸(草铵膦)溶液喷施烤烟叶片,研究了烟叶烘烤过程中烘烤特性的变化特征。结果表明:于烟叶工艺成熟期前7d喷施GS抑制剂,能够显著降低烘烤过程中烟叶的叶绿素、类胡萝卜素含量和多酚氧化酶(PPO)活性;增加烟叶失水速率和丙二醛(MDA)含量,显著提高烟叶烘烤后黄烟比例,并降低杂色烟比例。研究认为,在烟叶工艺成熟期前7d喷施GS抑制剂,可增强烟叶的易烤性和耐烤性,使烟叶更容易变黄,并同时减少棕色化反应的发生,但高浓度的GS抑制剂使烟叶失水速率过快,不利于烟叶定色,烘烤后青烟比例升高,对烟叶外观质量形成不利。     

Effect of Water Deficit on Accumulation of Dry Matter, Carbon and Nitrogen in the Kernel of Wheat Genotypes Differing in Yield Stability

Water stress effects on accumulation of dry matter, carbon andnitrogen in grains were analysed in varieties and species ofwheat differing in yield stability. Variable water environmentswere generated using a line source sprinkler system. Althoughlarge fluctuations occurred in the water potentials of the flagleaf and ear, grain growth remained relatively buffered undermoisture stress. Developing grains were at a lower moisturelevel throughout grain growth in plants subjected to moisturestress relative to the unstressed plants. Carbon content decreasedmore than the nitrogen content in the stressed grains of thespecies and varieties. Reduction in the duration of grain growthand the rate of dry weight accumulation induced by water stresswas more prominent in T. aestivum var. C306 and T. sphaerococcum.Grain yield was reduced significantly under water stress, themaximum being in the high yielding cultivar HD2329. Both grainnumber and grain weight were reduced in response to stress,the extent of reduction being different in different genotypes.Copyright1994, 1999 Academic Press Water deficit, yield stability, C and N accumulation, heat degree days     

Effect of matrine on primary human hepatocytes in vitro

Matrine is a bioactive component of the traditional Chinese medical herb Sophora flavescens that has been used in China to treat various kinds of diseases including virus hepatitis. However, the molecular mechanisms underlying its hepatoprotective effects remains elusive. In the present study, primary human hepatocytes were employed to elucidate the protective effects and molecular mechanisms of matrine. We observed that low concentrations of matrine had no significant impact on albumin secretion, but high concentrations (>140 mg/L) of matrine decreased the albumin secretion in hepatocytes. Western blot data indicated that matrine at 140 mg/L at 72 h induced protein expression of CYP2A6, CYP2B6 and CYP3A4. Furthermore, high concentrations of matrine reduced LDH and AST levels and were cytotoxic to hepatocytes, leading to a decreased cell viability and total protein amount. Moreover, low concentrations of matrine, enhanced the ECOD activity and decreased the level of NO₂⁻ induced by cytokines in human hepatocytes. Taken together, the present study sheds novel light on the molecular mechanisms of matrine and potential application of matrine in hepatic diseases.

Electronic supplementary material

The online version of this article (doi:10.1007/s10616-013-9680-1) contains supplementary material, which is available to authorized users.     

Spatiotemporal Context Awareness for Urban Traffic Modeling and Prediction: Sparse Representation Based Variable Selection

Spatial-temporal correlations among the data play an important role in traffic flow prediction. Correspondingly, traffic modeling and prediction based on big data analytics emerges due to the city-scale interactions among traffic flows. A new methodology based on sparse representation is proposed to reveal the spatial-temporal dependencies among traffic flows so as to simplify the correlations among traffic data for the prediction task at a given sensor. Three important findings are observed in the experiments: (1) Only traffic flows immediately prior to the present time affect the formation of current traffic flows, which implies the possibility to reduce the traditional high-order predictors into an 1-order model. (2) The spatial context relevant to a given prediction task is more complex than what is assumed to exist locally and can spread out to the whole city. (3) The spatial context varies with the target sensor undergoing prediction and enlarges with the increment of time lag for prediction. Because the scope of human mobility is subject to travel time, identifying the varying spatial context against time lag is crucial for prediction. Since sparse representation can capture the varying spatial context to adapt to the prediction task, it outperforms the traditional methods the inputs of which are confined as the data from a fixed number of nearby sensors. As the spatial-temporal context for any prediction task is fully detected from the traffic data in an automated manner, where no additional information regarding network topology is needed, it has good scalability to be applicable to large-scale networks.     

Genomic,molecular evolution,and expression analysis of NOX genes in soybean (Glycine max)

Reactive oxygen species (ROS) are versatile signaling molecules in sensing stresses and play critical roles in signaling and development. Plasma membrane NADPH oxidases (NOXs) are key producers of ROS, and play important roles in the regulation of plant-pathogen interactions. Here, we performed a comprehensive analysis of the NOX gene family in the soybean genome (Glycine max) and 17 NOX (GmNOX) genes were identified. Structural analysis revealed that the GmNOX proteins in soybean were as conserved as those in other plants. 8 duplicated gene pairs were formed by a Glycine-specific whole-genome duplication (WGD) event approximately 13 million years ago (Mya). The Ka/Ks ratios of GmNOX genes ranged from 0.04 to 0.28, suggesting that the GmNOX family had undergone purifying selection in soybean. Gene expression patterns showed different expression of these duplicate genes, suggesting that the GmNOXs were retained by substantial subfunctionalization during the soybean evolutionary processes. Subsequently, the expression of GmNOXs in response to drought and phytohormones were characterized via qPCR. Importantly, four GmNOXs showed strong expression in nodules, pointing to their probable involvement in nodulation. Thus, our results shed light on the evolutionary history of this family in soybean and contribute to the functional characterization of GmNOX genes in soybean.     

Activation of peroxisome proliferator-activated receptor-γ by rosiglitazone improves lipid homeostasis at the adipose tissue-liver axis in ethanol-fed mice

The development of alcohol-induced fatty liver is associated with a reduction of white adipose tissue (WAT). Peroxisome proliferator-activated receptor (PPAR)-γ prominently distributes in the WAT and plays a crucial role in maintaining adiposity. The present study investigated the effects of PPAR-γ activation by rosiglitazone on lipid homeostasis at the adipose tissue-liver axis. Adult C57BL/6 male mice were pair fed liquid diet containing ethanol or isocaloric maltose dextrin for 8 wk with or without rosiglitazone supplementation to ethanol-fed mice for the last 3 wk. Ethanol exposure downregulated adipose PPAR-γ gene and reduced the WAT mass in association with induction of inflammation, which was attenuated by rosiglitazone. Ethanol exposure stimulated lipolysis but reduced fatty acid uptake capacity in association with dysregulation of lipid metabolism genes. Rosiglitazone normalized adipose gene expression and corrected ethanol-induced lipid dyshomeostasis. Ethanol exposure induced steatosis and upregulated inflammatory genes in the liver, which were attenuated by rosiglitazone. Hepatic peroxisomal fatty acid β-oxidation was suppressed by ethanol in associated with inhibition of acyl-coenzyme A oxidase 1. Rosiglitazone elevated plasma adiponectin level and normalized peroxisomal fatty acid β-oxidation rate. However, rosiglitazone did not affect ethanol-reduced very low-density lipoprotein secretion from the liver. These results demonstrated that activation of PPAR-γ by rosiglitazone reverses ethanol-induced adipose dysfunction and lipid dyshomeostasis at the WAT-liver axis, thereby abrogating alcoholic fatty liver.     

思茅松松脂分类加工初探

通过对云南思茅松松脂的理化分析,论述了松脂生产加工中存在问题,提出了思茅松松脂分类加工的必要性.     

赤霉素和6-BA对苦豆子种子萌发生理特性的影响

以苦豆子种子为材料,研究了不同浓度的赤霉素(GA3)和6-苄基氨基嘌呤(6-BA)对苦豆子种子发芽特性的影响。结果表明,在一定浓度范围内,赤霉素和6-BA均能提高苦豆子种子发芽,而且延长浸种时间也可促进种子的萌发,其中以200 mg/L的赤霉素浸种8 h和60 mg/L的6-BA浸种8h效果最佳。