鸭呼肠孤病毒TaqMan与SYBR Green荧光定量检测方法的建立及比较

本研究旨在针对新型鸭呼肠孤病毒(NDRV)建立两种快速、敏感、特异的荧光定量PCR诊断方法并对其临床实用性进行比较.试验根据呼肠孤病毒S1基因序列设计合成1对特异性引物和1条MGB探针,分别建立TaqMan和SYBR GreenI两种荧光定量PCR检测方法,并对两种方法的特异性、灵敏性、重复性进行比较.结果 显示,两种...     

3种中间砧高接换种纽荷尔脐橙试验

采用温州蜜柑、椪柑、沙田柚为中间砧高接纽荷尔脐橙,对其成活率、新梢长度、粗度以及产量、品质等进行了测定.结果表明:温州蛮柑成活率最高,为87.1%,各次梢生长势最强.平均单株产量最高(9.55kg),而以椪柑为中间砧高接纽荷尔脐橙各性状表现均较差.从品质方面综合分析.以沙田柚为中间砧高换纽荷尔脐橙最好.     

Virulence and inoculum density‐dependent interactions between clubroot resistant canola (Brassica napus) and Plasmodiophora brassicae

To mitigate the impact and dissemination of clubroot in western Canada, canola (Brassica napus) producers have relied on clubroot resistance traits. However, in 2013 and 2014, new strains of the clubroot pathogen, Plasmodiophora brassicae, emerged that are virulent on most clubroot‐resistant (CR) canola genotypes. Novel strains of the pathogen were inoculated onto two susceptible canola cultivars, one resistant line and six CR cultivars. Although all cultivars/lines showed a susceptible response to inoculation with the new strains of P. brassicae, the severity of disease reaction, root hair infection rates and the amount of P. brassicae DNA present in each canola genotype varied depending on the strain. In addition, the effect of inoculum density on disease severity and gall formation was recorded for one of these new strains on a universally susceptible Chinese cabbage cultivar and one susceptible and 10 resistant canola genotypes. Although root galls were observed at an inoculum density of 10³ spores per mL of soil, clear differentiation of susceptible and resistant reactions among canola cultivars/lines was not observed until the inoculum density reached 10⁵ spores mL^?1. At a spore density of 10⁶ spores mL^?1 and above, all cultivars/lines developed susceptible reactions, although there was some differentiation in the degree of reaction. This study shows the potential to develop a unique disease profile for emergent clubroot pathotypes and shows a useful range of spore densities at which to study new P. brassicae strains.     

Statistical Research on the Bioactivity of New Marine Natural Products Discovered during the 28 Years from 1985 to 2012

Every year, hundreds of new compounds are discovered from the metabolites of marine organisms. Finding new and useful compounds is one of the crucial drivers for this field of research. Here we describe the statistics of bioactive compounds discovered from marine organisms from 1985 to 2012. This work is based on our database, which contains information on more than 15,000 chemical substances including 4196 bioactive marine natural products. We performed a comprehensive statistical analysis to understand the characteristics of the novel bioactive compounds and detail temporal trends, chemical structures, species distribution, and research progress. We hope this meta-analysis will provide useful information for research into the bioactivity of marine natural products and drug development.     

The Bright Side of Gelatinous Blooms: Nutraceutical Value and Antioxidant Properties of Three Mediterranean Jellyfish (Scyphozoa)

Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest.     

新型A型H1N1猪流感疫情动态及防控措施

2009年3月18日由墨西哥发端的人类大流行性甲型(A型)H1N1流感疫情迅速在全球蔓延,并已扩散到中国。新型A型H1N1流感突破种间屏障由人传染给猪、禽,并相继在北美、南美、大洋洲出现疫情。2009年4月21日,新型A型H1N1猪流感疫情首次在北美的加拿大发生;2009年6月24日,在南美的阿根廷发生猪流感疫情;2009年7月24日,远在大洋洲的澳大利亚也出现猪流感疫情;更糟糕的是在2009年7月23日,在南美紧邻阿根廷的智利的禽类(火鸡)首次发生A型流感疫情。此次新型A型H1N1流感疫情呈现大流行病学显著变化:①突破种间屏障由人传染给猪、禽;②突破地理屏障,在三大洲先后暴发规模不等、强度不一的多起疫情。因此,我国卫生主管部门、兽医主管部门和出入境检验检疫部门应高度戒备,密切关注,采取严格的生物安全措施,严防疫情疫病跨越国境,特别是防止新型A型H1N1流感疫情在人群、猪群、禽群之间相互传播,避免疫情在人类和动物进一步扩散。     

改性再生油合成可降解材料制备缓释肥的技术参数研究

【目的】回收油提纯后直接合成的生物基聚氨酯(PUs),耐湿耐热性能较差,不适宜于用作肥料缓释包膜材料。本文在聚氨酯合成过程中引入能提高产品的机械、耐水、抗老化等性能的γ―氨丙基三乙氧基硅烷(KH550)对PUs进行改性,并初步测定了该包膜肥料养分的释放特征。【方法】回收的食用油和反复使用的炸油来自贵州省毕节市的餐馆。依次用磷酸、蒸馏水、NaOH、NaCl清洗提纯后得到再生油。将制得的再生油与过氧乙酸按质量比1∶0.3混合,经过中和、洗涤、蒸馏,与乙二醇反应生成醇化再生油。将醇化再生油与KH550在80℃下按一定比例混合搅拌2 h,制成含KH550分别为0、10%、20%和30%的醇化再生油混合物。在BYC-300型包衣机中加入150 g尿素(包衣温度为60℃,转速为1300 r/min),按尿素重量的3%加入上述混合物,再滴加MDI-50进行包衣,即制备得KH550改性聚氨酯(K-PUs)包膜尿素(PCUs-0、PCUs-1、PCUs-2、PCUs-3)。参考Oertli等方法测定了该包膜肥料的缓释性能。【结果】1)回收油经过多步提纯后得到的再生油仍保持原油的分子结构,含有官能团碳碳双键。2)再生油经过预改性后明显增加活性基团羟基,为聚氨酯的合成提供反应基团。3)通过化学反应将再生油合成为新型生物基聚氨酯,并在聚氨酯合成过程中成功引入硅烷偶联剂KH550,从而得到改性PUs包膜材料。4) KH550的存在使得改性后PUs的疏水性相比于未改性的提高了48%~74%;孔隙率相比于未改性前降低了31%~54%;热稳定性相比于未改性的PUs在T5%提高了3%~11%、T50%提高了6%~32%、T80%提高了4%~11%。氮素模拟试验表明PCUs氮的累积释放速率明显降低。改性后的PCUs氮素在第30天累积释放不超过70%,未改性PCUs氮素在第30天累积释放超过90%。5)当KH550含量为20%时,改性PUs具有最大的接触角和最低的孔隙率,其值分别为113.31°和10.91%,该条件下制备的PCUs综合性能最佳。【结论】以回收油为原料合成新型生物基聚氨酯,需进行醇化后,再与硅烷偶联剂混合,并加入MDI-50进行反应,形成KH550含量为20%的改性生物基聚氨酯。以该材料包膜的尿素30天氮素累积释放量不超过70%,可以满足可降解缓释肥的要求。