Isolation and Identification of Pathogens Causing Marigold (Tagetes erecta L.) Black Spot in Beijing,China

Black spot leads to great marigold losses worldwide. The disease is characterized by black spots on leaves and stems in its early stages, and the whole plant has black rot at the advanced stage. In this report, 6 of 217 Alternaria strains isolated from lesions of marigold plants in Beijing were randomly selected. The morphological characteristics and a pathogenic tree based on two protein‐coding genes (gpd and alt a 1) indicated that Alternaria tagetica is the causal agent of marigold black spot in Beijing. All six Alternaria strains could successfully re‐infect marigold, but they could not infect carrot or zinnia by either spore spray in a greenhouse or planting experiments in the epidemic area. This is the first report of the A. tagetica pathogen being isolated from marigold in Beijing.     

Increased cold tolerance in Arabidopsis thaliana transformed with Choristoneura fumiferana glutathione S-transferase gene

A glutathione S-transferase (GST) gene cloned from the lepidopteran spruce budworm, Choristoneura fumiferana Clem. was transformed into the model plant Arabidopsis thaliana. The CfGST-transgenic and wild-type A. thaliana were subjected to 4 and 10 °C for 48 h and their cold resistance was studied. The GST activity of the transgenic plants was 46.6 and 35.7 % higher than that of the wild-type plants after 48 h under 4 and 10 °C, respectively. Relative membrane permeability and malondialdehyde content in the transgenic plants were lower while contents of the chlorophyll and proline were higher than those in the wild-type plants under 4 and 10 °C. The survival rate of the transgenic plants was 43.7 % for 24 h under 0 °C, while survival rate of wild-type plants was 28.3 %. The results indicated that the insect GST could enhance cold resistance in the transgenic A. thaliana.     

Different culture conditions used for arresting the G0/G1 phase of the cell cycle in goldfish (Carassius auratus) caudal fin-derived fibroblasts

One of the most important factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We investigated the effects of serum starvation, culturing to confluence and roscovitine treatment on the cell cycle synchronization of goldfish caudal fin-derived fibroblasts by flow cytometric analysis. The results show that culturing the cells to confluence (85.5%) and roscovitine treatment (82.71%) yield a significantly higher percentage of cells arrested in the G0/G1 (P < 0.05) phase than serum starvation (62.85%). Different concentrations of roscovitine (5, 10, or 15 μM) induce cell cycle arrest at the G0/G1 phase.     

醛固酮对新生大鼠心肌成纤维细胞分泌ET、NO功能的影响

目的: 探讨醛固酮对新生大鼠心肌成纤维细胞(CFs)分泌内皮素(ET)、一氧化氮(NO)的影响.方法: 采用胰酶消化法和差速贴壁分离法获取CFs,应用放射免疫分析法、硝酸还原酶法分别测定不同条件下培养的CFs培养液中的ET、NO水平.结果: 一定浓度范围内的醛固酮可按剂量依赖方式促进CFs分泌ET,抑制CFs分泌NO,使ET/NO比值上升;螺内酯可阻断醛固酮的上述作用(P<0.01).结论: 醛固酮可能通过影响CFs分泌ET、NO,从而改变生物活性物质网络平衡关系,发挥其促心肌纤维化作用.     

饥饿和饱食状态下丰鲤与其亲本的活动水平和活动节律

使用Videomex-V影像运动监视系统全天监测丰鲤(Cyprinus carpiovar.Xingguo♀×Cyprinus carpiovar.mirror splittered♂)、散鳞镜鲤(Cyprinus carpiovar.mirror splittered♂)和兴国红鲤(Cyprinus carpiovar.Xingguo♀)的活动(每种鱼12条,饥饿和饱食各6条)。结果显示,3种鱼饥饿时的活动水平都显著低于饱食时,但3种鱼白昼或夜间的相对活动水平都不受摄食与否的显著影响;饥饿或饱食时,丰鲤的活动水平与散鳞镜鲤都无显著差异,并且都显著高于兴国红鲤;丰鲤饥饿时的活动节律与散鳞镜鲤和兴国红鲤都不相似,饱食时的活动节律与散鳞镜鲤更相似。总的来看,丰鲤的活动水平和活动节律与散鳞镜鲤更为相似[动物学报51(5):806-812,2005]。     

On the classification of Calligonum juochiangense and C. pumilum (Polygonaceae)

After observing specimens of Calligonum pumilum Losinsk. and C. juochiangense Y. X. Liou in both the field and in herbarium collections, it was found that the morphological characters of these two species are quite different, especially with respect of the twisted direction of fruit ribs, number of bristle rows along each rib, rigidity and degree of interweaving of bristles, as well as their geographic distribution. Therefore, it is concluded that C. pumilum and C. juochiangense should be accepted as two independent species.     

Synthesis of mono-carbonyl analogues of curcumin and their effects on inhibition of cytokine release in LPS-stimulated RAW 264.7 macrophages

Curcumin has been reported to possess multifunctional bioactivities, especially the ability to inhibit proinflammatory induction. We previously demonstrated that the mono-carbonyl analogues of curcumin possessed improved pharmacokinetic profiles both in vitro and in vivo. In this study, we synthesized and examined a series of 5-carbon linker-containing mono-carbonyl analogues of curcumin with potent inhibitory activities against TNF-α and IL-6 release in LPS-stimulated RAW 264.7 macrophages. Discussion and conclusions are given regarding structure-activity relationships (SAR). The two most potent analogues among the tested compounds, B75 and C12, exhibited anti-inflammatory abilities in a dose-dependent manner in macrophages. This raises the possibility that mono-carbonyl analogues of curcumin might serve as potential agents for the treatment of various inflammatory diseases.     

Design,synthesis, and pharmacological evaluation of N-(4-mono and 4,5-disubstituted thiazol-2-yl)-2-aryl-3-(tetrahydro-2H-pyran-4-yl)propanamides as glucokinase activators

A series of N-thiazole substituted arylacetamides were designed on the basis of metabolic mechanism of the aminothiazole fragment as glucokinase (GK) activators for the treatment of type 2 diabetes. Instead of introducing a substituent to block the metabolic sensitive C-5 position on the thiazole core directly, a wide variety of C-4 or both C-4 and C-5 substitutions were explored. Compound R-9k bearing an iso-propyl group as the C-4 substituent was found possessing the highest GK activation potency with an EC₅₀ of 0.026 μM. This compound significantly increased both glucose uptake and glycogen synthesis in rat primary cultured hepatocytes. Moreover, single oral administration of compound R-9k exerted significant reduction of blood glucose levels in both ICR and ob/ob mice. These promising results indicated that compound R-9k is a potent orally active GK activator, and is warranted for further investigation as a new anti-diabetic treatment.