应用轻型飞机防治马尾松毛虫的试验Ⅰ．喷施四种药剂防治的效果

马尾松毛虫Dendrolimus punctatus Walker是马尾松林重要害虫。林间应用超轻型飞机大面积喷洒溴氰菊酯超低容量喷雾、白僵菌纯孢子油剂、菌药混合液超低容量喷雾以及喷洒白僵菌菌粉,其防治效果分别为96．5%、85．7%、95．6%、86．5%。上述的防治措施可作为单独的措施或综合防控中的配套措施使用,同时应用飞机防治解决了树高、林密、水源缺乏、劳力工资昂贵等条件给防治工作带来的困难,是一种适应林区林业生产整体水平而又快速、高效、经济的防治手段。     

使用Cytoscape对生物网络数据的建模和分析

生物网络是系统生物学研究的重要内容。本文介绍了多种常用复杂生物网络可视化系统,针对Cytoscape系统在可视化的建模过程以及在建模过程中使用到的布局算法进行对比研究,并利用Cytoscape系统中丰富的插件对复杂网络数据进行分析,包括对数据进行网络分析和更改、使用BINGO插件进行基因注释、使用AGILENT LITERATURE SEARCH(ALS)插件搜索基因相互作用文献等。     

Effect of lipoic acid on redox regulation,digestive and absorptive function in intestine of mice fed high fat diet

AIM:To elucidate the molecular mechanisms of lipoic acid (LA) on redox regulation and digestive function in intestine of C57BL/6 mice fed high fat diet (HFD).METHODS:C57BL/6 mice were randomly assigned to one of three groups (n=8).The control group consumed an ordinary diet.The other two experimental groups were fed with a high fat diet, high fat plus 0.1% LA.After 6 weeks, the activities of digestive enzymes were examined.In order to evaluate the antioxidant status of the mice, superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant capacity (TAC) and reactive oxygen species (ROS) in intestinal homogenate were measured.To investigate the molecular mechanisms underlying the effects of LA, the gene expression profiles in intestine were examined using the GeneChip microarray system.RESULTS:A depressed antioxidant defense system, accompanied by digestive and absorptive function impairment, was observed in HFD-fed mice.These changes were partially restored in the LA-treated group.DNA microarray analysis of intestine showed that LA ingestion up-regulated the expression of genes related to free-radical scavenger enzymes, digestive enzymes and transporters.CONCLUSION:Treatment with LA improves redox homeostasis and the function of intestine in mice fed HFD.The mechanism may involve preventing oxidative stress by scavenging ROS directly and increasing those of free-radical scavenger enzymes gene expression indirectly.     

Pharmacokinetics of cimetidine in dogs after oral administration of cimetidine tablets

Long-term oral treatment with cimetidine is recommended to reduce vomiting in dogs with chronic gastritis. Despite this, few studies have specifically examined the plasma disposition and pharmacokinetics of cimetidine in dogs, particularly following repeated oral administration. The pharmacokinetics of cimetidine following oral administration as tablets was investigated in healthy dogs. Cimetidine was absorbed rapidly post-treatment ( t _max = 0.5 h). A mean absolute bioavailability of 75% was calculated following a single oral administration of 5 mg cimetidine/kg body weight. After intravenous administration, a plasma half-life of 1.6 h was calculated. Repeated oral administration at the recommended dose rate and regime (5 mg/kg body weight three times daily) for 30 consecutive days did not lead to any accumulation of cimetidine in plasma. Food intake concomitant with oral administration of cimetidine delayed ( t _max = 2.25 h) and decreased the rate and extent of absorption ( AUC ) by about 40%. Cimetidine was well absorbed in fasted dogs. Administration of food decreased the bioavailability of cimetidine by 40%. Cimetidine does not accumulate over time in plasma when administered long term to dogs.     

Change of reactive oxygen species production in co-culture model of rat astrocytes and motor neurons VSC 4.1

AIM: To explore the mutual effect of co-culture of wild-type astrocytes (ASC) and motor neurons VSC4.1 (VSC) on the respective ability to produce reactive oxygen species (ROS). METHODS: The inhibition rates of cell growth in ASC and VSC in co-culture or independent culture was detected after exposed to excitatory stimulus by MTT method. Real-time observation of ROS production by ASC and VSC labeled with Hoechst 33342 was detected by confocal microscopy under the conditions of co-culture or independent culture. RESULTS: Higher concentration of glutamate induced a higher inhibition rate in mixed cell growth than that in ASC alone, while lower concentration of glutamate induced a higher inhibition rate in mixed cell growth than that in VSC only. Real-time observation by confocal microscopy showed that ROS production by VSC under the condition of co-culture, which showed a notable increase at 15 min, was significant less than that in independent culture, which peaked at 5 min and was gradually decreased. ROS production by ASC in co-culture began to increase significantly at 10 min. CONCLUSION: Compared to independent culture, ASC reduces the resting ROS production by co-cultured with VSC, while ASC prolongs the duration of ROS production by VSC after exposed to excitatory stimulus.     

Sesbania seed collections in Southern Africa

The International Centre for Research in Agroforestry (ICRAF) is a member of the Consultative Group on International Agricultural Research (CGIAR) system and has recently established a Multipurpose Tree Germplasm Resource Unit (MPT-GRU) in Nairobi, Kenya. The first major activity of the MPT-GRU was to undertake a regional germplasm collection ofSesbania in 5 countries in southern Africa in a collaborative mode with National Agricultural Research Services (NARS). The collections took place in Botswana, Malawi, Namibia, Zambia and Zimbabwe.Key elements of a generalised collaborative mode (the model) are indicated follwed by a summary of actual events. The initial phase involved joint planning and training sessions between NARS, three sister CGIAR centres and one regional institution, the Southern Africa Development Conference (SADC) Regional Gene Bank (SRGB). This was followed by actual collections during 1993 led by National scientists with different levels of CGIAR participation in each of the five countries. The International Board of Plant Genetic Resources (IBPGR) took the lead in pre-collection training activities, ICRAF for developing the collection programme and the International Livestock Centre for Africa (ILCA) for seed drying, testing and despatch for field trials. NARS gene banks guided the necessary administrative processes. The ICRAF lead scientist for the species and provenance evaluation phase was a crucial member of the planning process thus allowing integration of the collection with the eventual field evaluation. The article focuses on the collection strategy, administrative protocols for actual collections and summary results. Some advantages and difficulties associated with the collection programme and model are discussed. The collections were important in bringing together agriculturalists and foresters in a common germplasm collection exercise.     

Induction of resistance against downy mildew pathogen in pearl millet by a synthetic jasmonate analogon

The synthetic 1-oxo-indanoyl-l-isoleucine methyl ester (Ind-Ile-Me) represents a highly active mimic of octadecanoic phytohormones, which are involved in plant defenses against pathogens and pests. Seed treatments and foliar spray with Ind-Ile-Me were tested for induced resistance against downy mildew disease caused by the phytopathogenic oomycete Sclerospora graminicola in pearl millet (Pennisetum glaucum) under greenhouse and field conditions. Under greenhouse conditions, a 50% protection level was achieved after seed treatment. Seed treatment in combination with foliar spray resulted in 60% protection. The induction of resistance was correlated with the enhanced activities of defense-related proteins such as phenylalanine-ammonia-lyase, peroxidase, and enhanced level of hydroxyproline-rich glycoproteins. Under field conditions, a maximum protection of 62% was recorded upon seed treatment along with foliar spray. Hence, it infers that Ind-Ile-Me can be used as a valuable protection compound at least in downy mildew disease management.     

江西省芝麻地方种质表型性状遗传多样分析

【目的】对江西省芝麻地方种质资源进行表型性状遗传多样分析,为江西芝麻种质资源的有效利用及开发提供理论参考。【方法】依托“第三次全国农作物种质资源普查与收集行动”从江西省39个县(市、区)收集到的132份芝麻地方种质为试验材料,对其23个表型性状(12个质量性状和11个数量性状)进行测定,并计算遗传多样性指数和变异系数。同时,对11个数量性状进行相关分析,并对供试种质进行聚类分析。【结果】23个表型性状的平均遗传多样性指数为1.2821,其中,12个质量性状的遗传多样性指数为0.3217~1.0307,平均0.7290;11个数量性状的变异系数为4.70%~43.58%,遗传多样性指数为1.6138~2.0627,平均1.8855。3种粒色类型芝麻种质中,以46份白芝麻种质表型性状的平均遗传多样性指数最高,为1.3602,74份黑芝麻种质和12份其他粒色(黄色、褐色、黄褐色、红褐色等)芝麻种质表型性状的平均遗传多样性指数分别为1.1782和1.0476。生育期与株高、始蒴高度、蒴果长、千粒重和蛋白含量呈极显著正相关(P<0.01,下同),但与含油量呈极显著负相关。供试的132份芝麻种质资源可分为四大类,不同类群种质的来源地存在地理位置的交错分布现象,其中,第Ⅰ类群可作为潜在选育芝麻高含油量新品种的亲本材料,第Ⅱ类群可作为潜在高产优良芝麻材料利用,第Ⅲ类群可作为潜在矮杆株型的亲本材料,第Ⅳ类群可作为潜在的高蛋白型亲本材料加以利用。【结论】江西芝麻地方种质资源的主要表型性状变异较大,遗传多样性较丰富,其中以46份白芝麻种质的遗传多样性更丰富。种质间亲缘关系与地理来源无必然联系。以高产高蛋白为育种目标时应选择株高较高,始蒴高度适中、蒴果较大、千粒重较高的材料为亲本,并据此进行后代选择。