Cytochrome P-450 in insects: 4. Reconstitution of cytochrome P-450-dependent monooxygenase activity in the house fly

Two cytochrome P-450-containing fractions were isolated from detergent-solubilized house fly microsomes by hydrophobic chromatography on a tryptamine-Sepharose gel. These fractions (designated P-450-1 and P-450-2) were distinctive in their spectral characteristics and in their profiles following electrophoresis in the presence of sodium dodecyl sulfate. Both fractions exhibited NADPH-dependent epoxidase activity when reconstituted with purified house fly cytochrome P-450 reductase and phospholipid. The aldrin epoxidase activity of fraction P-450-1 was twice that of P-450-2 even though heptachlor epoxidase activity of the fractions was equivalent. O-Demethylase activity with 7-methoxy-4-methylcoumarin was detectable only in the P-450-2 fraction.     

马斯京根法洪水演算公式参数确定方法的商榷

针对近年来最小二乘法用于马斯京根法出现的一种趋势,从流量演算法的水力学理论出发,剖析了马斯京根法进行洪水演算的原理,指出了马斯京根法中参数的物理意义.同时通过马斯京根法的理论解释,从理论上论证了康吉演算法推算具有衰减特性的洪水波运动必须满足的条件,指出了最小二乘法用于马斯京根法公式参数确定时造成的参数物理意义的模糊,并且该做法并不能从理论上保证该条件的成立以及可能出现的问题,所得结论愿与读者商榷.     

爪哇根结线虫-β1,4-内切葡聚糖酶基因cDNA全长克隆和序列分析

 以爪哇根结线虫为材料,根据同源序列法分别进行3'末端和5'末端的RACE,获得-β1,4-内切葡聚糖酶基因cDNA全长。此cDNA全长序列为1 675 bp,包括1 521 bp的完整ORF,编码一含506 aa的多肽。该基因命名为Mj-eng3-,其推导蛋白的编码氨基酸与南方根结线虫的-β1,4-内切葡聚糖酶基因MI-ENG-1、MI-ENG-3和MI-ENG-4的同源性为95.3%、95.8%和85.3%,与另外5个植物寄生线虫β-1,4-内切葡聚糖酶基因推导蛋白PP-ENG-1、GR-ENG-1、GT-ENG-1、HG-ENG-1、HS-ENG-1编码氨基酸的同源性分别为51.2%、43.7%、43.7%、46.8%和45.3%。     

Detection and Quantification of Spongospora subterranea in Soil, Water and Plant Tissue Samples Using Real-Time PCR

A sensitive real-time polymerase chain reaction (PCR) assay was developed for the quantification of Spongospora subterranea, the cause of powdery scab and root galling in potato, and the vector of Potato mop top virus. A specific primer pair and a fluorogenic TaqMan® probe were designed to perform a quantitative assay for the detection of S. subterranea in soil, water and plant tissue samples. The assay was tested using DNA from cystosori, zoospores, plasmodia and zoosporangia of the pathogen. DNA was extracted directly from cystosori suspended in water and from clay soil with varying levels of added cystosori. DNA obtained from zoospores released into nutrient solution by cystosori in the presence of tomato bait plants was also tested, as was DNA from plasmodia and zoosporangia in infected tomato roots. In many cases, detection was successful even at low inoculum levels. This specific quantitative assay could therefore be a useful tool for studying the biology of S. subterranea, and for the optimisation of disease avoidance and control measures.     

Interleukin-4 increases cortisol release and decreases adrenal androgen release from bovine adrenal cells

ACTH is the primary regulator of adrenal function during acute stress. However, during chronic inflammatory stress additional factors play a major role in the regulation of adrenal secretion. Many cytokines circulate in the blood and are synthesized and released from adrenal tissue. Furthermore, these peptides modify adrenal function. Recently, interleukin-4 (IL-4) was demonstrated to be released from a human adrenal tumor cell line. Therefore, we hypothesized that normal bovine adrenocortical cells could express IL-4 and that this cytokine may modify adrenal function. We determined that IL-4 and IL-4 receptors (IL-4R) are expressed in the bovine adrenal cortex whereas the expression of IL-4 and IL-4R in the adrenal medulla was not apparent. Exposure of dispersed bovine adrenocortical cells isolated from the zona fasciculate to IL-4 did not modify basal release of cortisol. However, the ACTH-stimulated release of cortisol from the bovine adrenal cells was augmented by IL-4. IL-4 exposure had no affect on adrenal androgen release from bovine zona reticularis cells, but IL-4 inhibited the ACTH-stimulated release of adrenal androgens from these cells. The effects of IL-4 on ACTH-stimulated cortisol and adrenal androgen release were dependent upon the IL-4 incubation interval and the IL-4 concentration. Because communication between the immune and endocrine systems is important in inflammatory conditions, IL-4 may play a role in coordinating the adrenal response to inflammatory stress.     

Comparative in vitro antimicrobial efficacy of commercial ear cleaners

The aim of this study was to compare the antimicrobial efficacy of ear cleaners against Staphylococcus intermedius, Pseudomonas aeruginosa and Malassezia pachydermatis. Single isolates of each organism were incubated in duplicate at 38 °C for 30 min with each ear cleaner diluted 1/2 to1/256 in phosphate‐buffered saline. Positive and negative controls were included. Aliquots were then incubated for 16–18 h on sheep blood agar (bacteria) or for 3 days on Sabouraud's dextrose agar (Malassezia) at 38 °C. The lowest dilutions exhibiting 100% antimicrobial efficacy for S. intermedius were: Cleanaural^® Dog 1/32; Sancerum^® 1/16; Otoclean^® 1/4; EpiOtic^® 1/2; MalAcetic^® 1/2; and Triz Plus^® 1/2. The results for P. aeruginosa were Sancerum^® and Triz Plus^® 1/16; Cleanaural^® Dog and EpiOtic^® 1/8; Otoclean^® 1/4; and MalAcetic^® 1/2. Results for M. pachydermatis were: Cleanaural^® Dog 1/32; Sancerum^®, Otoclean^®, EpiOtic^® and Triz Plus^® 1/8; and MalAcetic^® 1/4. Cleanaural^® Cat, MalAcetic HC^® and Triz EDTA^® did not display any antimicrobial activity at any dilution. Antimicrobial activity appeared to be associated with the presence of isopropyl alcohol, parachlorometaxylenol and a low pH. The results of this study may help clinicians make evidence‐based decisions when selecting ear cleaners for use in individual cases.     

家蚕BmN细胞S期同步化体系建立

细胞S期为DNA复制期,探索细胞S期的同步化将为研究各种调控因子对DNA复制、细胞分裂和增殖的影响奠定基础。本研究以家蚕BmN细胞为研究对象,采用脱氧胸苷(TdR)双阻断、脱氧胸苷-诺考达唑(TdR-Nocodazole)双阻断及羟基脲(HU)法,探索BmN细胞S期同步化的最佳体系。结果发现,TdR双阻断法处理对BmN细胞S期的同步化效率为67.2%,TdR-Nocodazole双阻断法处理为69.7%,HU处理对S期同步化效果最好,达90%以上。进一步对HU处理后不同释放时间点的细胞进行研究发现,1 mmol/mL HU处理后释放7 h时BmN细胞S期同步化效率最高,达94.9%。通过不同处理方法研究家蚕BmN细胞的S期同步化效果,发现1 mmol/mL的HU处理16 h,然后于正常培养基中释放7 h,可有效的将BmN细胞同步化在S期,且该处理方法简单,易于操作。     

残膜机械化回收技术

地膜具有保墒、提高地温、抑制杂草生长和增产增收等作用,得到了广泛应用,并极大地促进了我国农业经济的发展。但是残留在土壤中的地膜极难降解,给农业生产和生态环境造成了巨大危害,残膜回收对于保护耕地、改善农田生态环境具有重要的意义。总结了国内外残膜回收技术的研究现状及研究方法,指出我国残膜回收机具存在的主要问题,提出了实施机械化残膜回收技术的建议,为机械化回收残膜的研究提供理论依据。      

基于数据挖掘的熊继柏教授诊疗失眠模型构建研究

目的 构建熊继柏教授关于失眠的辨证论治模型。方法 通过对熊继柏教授治疗失眠的162人、254例次病案进行整理,运用Weka 3.7.12软件,采用FP-Growth算法,对就诊患者中不同性别与年龄段的证候特点、方剂间配伍、证候与用方进行关联规则分析,使用SPSS 17.0软件对常用药物进行R型系统聚类分析。结果 就诊的失眠患者证候特征随年龄变化由单纯虚证或实证逐渐演变为虚实夹杂证,男性与女性的失眠证候特点各异;熊继柏教授治疗失眠的4个常用方剂组合中,黄连温胆汤与痰热内扰证相关联,黄连温胆汤合酸枣仁汤与痰热兼肝郁化火证相关联,酸枣仁汤合孔圣枕中丹与肝肾阴虚相关联,黄连温胆汤、酸枣仁汤、孔圣枕中丹3方合用与肝肾阴虚合并痰热证相关联。常用治疗失眠的药物为酸枣仁、龙齿、甘草、茯神、黄连、半夏、陈皮、竹茹、枳实、知母等,大致可分为清热化痰、重镇安神、育阴潜阳3类。结论 熊继柏教授辨治失眠,多责之于痰热内扰、肝郁化火、肝肾阴虚,辨证注重辨舌脉,因证选方,经方与时方灵活搭配应用。