细菌叶绿素a高产菌株的选育和发酵工艺优化#br#

目的 结合各种诱变手段,获得细菌叶绿素a(bacteriochlorophyll a, Bchla)的高产菌株,并优化其发酵工艺,提高产量。方法 以球红假单胞菌ATCC17023为出发菌株,通过紫外、ARTP(常压室温等离子体)及亚硝基胍单独诱变或组合诱变,结合含氯化胆碱的抗性平板进行筛选。调整发酵培养基中碳氮源组分和比例,优化种龄、接种量、发酵pH、摇瓶装量、转速及温度等发酵培养条件。结果 通过多轮筛选,得到突变高产菌株,其发酵单位达到285.7μg/mL,为原始出发菌株的114倍。采用优化后的发酵工艺,经50L发酵罐放大培养,最高效价单位达到296.6μg/mL。结论 获得Bchla的高产菌株和摇瓶发酵工艺,并经50L发酵罐放大验证,为大规模商业化生产奠定了良好的基础。     

浦东国际机场致倦库蚊和淡色库蚊的调查研究

目的了解致倦库蚊和淡色库蚊在浦东机场的分布与活动规律。方法帐诱法、灯诱法、人诱法、捞勺法和人工小时法。结果致倦库蚊和淡色库蚊是浦东国际机场的优势蚊种,4-11月均有危害;灯诱法调查,季节消长呈坡型,蚊虫于4月出现,5-6月达到高峰,10-11月逐渐减少至消失;蚊虫活动（帐诱法）主要在晚上,黄昏时有群舞习性,活动高峰为日落后1～4h,白天基本不活动;刺叮（人诱法）高峰时间为21：00,叮人频率最高为42次/15min;入室蚊虫以19：00-22：00为多,入室率最高为9只/15min;幼虫主要孳生于池塘、水坑、洼地、下水道和容器等污染或干净的静止水体中。结论致倦库蚊和淡色库蚊是浦东国际机场危害人类的常见蚊种,其活动规律的研究对媒介控制和虫媒病的预警提供了技术支撑。     

Seasonal and gender variation of peroxisome proliferator activated receptors expression in brown trout liver

PPAR isotypes have been previously identified in the teleost brown trout (Salmo trutta f. fario) and their organ distribution pattern established. Being that the liver is a vital metabolic organ presenting expression of all isotypes and also knowing that estrogens/estrogen receptors seem to interact with PPARs, we hypothesized that the latter may very well change seasonally. So, we studied the expression of these receptors in the liver, along the annual reproductive cycle and in both genders. According to real-time RT-PCR, PPARα mRNA expression in females was significantly higher in May and lower in September than in other seasons. No significant variation was observed along the year in males. A significant difference between genders occurred in May, when PPARα expression was higher for females. PPARβ expression showed little variation along the reproductive cycle in females, but in males it was significantly higher in December than in the other seasons. No significant differences existed between genders. PPARγ was more expressed in February than in September and December, for females. As to males, it was more expressed in February than in all other seasons. No significant differences were observed between genders. The study proved our hypothesis that PPARs gene expression varies along the year. Moreover, PPARα expression in females followed the same annual variation pattern as peroxisome volumes and enzyme activities, and an inverse pattern relatively to the salmonid type annual plasma estradiol levels. The data agrees with the idea that PPARα is under estradiol modulation and that cross-talk between this receptor and the estrogen receptor possibly exists.     

血吸虫病流行区居民封洲禁牧依从性调查

目的了解我国血吸虫病流行区居民对封洲禁牧措施的依从性。方法根据人群血吸虫感染率〉10%、5%～10%和〈5%3个层次,在湖南、湖北、江西、安徽、江苏、四川省和云南省的血吸虫病流行村分层整群抽样,随机抽取2 204名居民进行问卷调查,调查其对封洲禁牧、舍饲圈养措施的认可情况。结果78.4%的居民认可封洲禁牧措施,3.7%的居民不支持。关于家畜舍饲圈养与血防两者之间的关系,83.9%的调查对象认为两者之间有关联,3.1%认为无关联;在3层不同感染率地区中,认为有关联的居民分别占调查人数的81.7%、85.1%和84.9%;认为无关联的各层之间差异有统计学意义（χ^2=45.121,P〈0.05）,感染率为5%～10%和〈5%的地区之间差异无统计学意义（χ^2=0.171,P〉0.05）,感染率〉10%的地区与其他2组差异有统计学意义（χ^2=45.045,P〈0.05）。家畜敞放的主要原因分别是舍饲圈养成本高（36.2%）、不习惯（26.4%）和没有地方舍饲圈养（25.4%）。结论应根据各地的经济水平、地理环境、农业生产状况、居民文化程度和生产习惯等社会经济情况,因地制宜地落实和巩固封洲禁牧舍饲圈养措施。     

储藏干果粉螨污染调查

目的 了解仓储干果污染粉螨的种类及其密度。方法 采集干果商店和仓库的储藏干果样本,分离其中的孳生粉螨,制备螨类玻片标本,光镜下观察其形态特征,进行鉴定和计数,并计算孳生密度、丰富度指数、多样性指数、物种均匀度等指标。此外,选择粉螨孳生数目较高的干果,进行人工环境下粉螨的培养观察,以了解其消长情况。结果 从49种干果样本共获得12种粉螨,隶属于6科10属,其中以甜果螨、腐食酪螨、粗脚粉螨、伯氏嗜木螨为优势螨种,在桂圆、平榛子、话梅等样本中孳生密度较高,分别为79.78、48.91、35.73只/g。对粉螨的季节变化调查发现平均孳生密度在7、10月份较高,丰富度指数和多样性指数均在7月份达到最高,均匀度指数则在1、4月份较高。人工环境下观察伯氏嗜木螨和腐食酪螨的消长情况,发现伯氏嗜木螨孳生密度逐渐下降,而腐食酪螨先增后降。结论 储藏干果的粉螨污染情况严重,应当采取积极有效的防制措施来控制粉螨的孳生,以降低粉螨带来的危害。     

2011～2015年宁波地区白纹伊蚊孳生调查分析

本研究通过对2011 ～2015年4～11月每月上、下旬对不同生境中的积水容器进行调查,分别计算容器指数、房屋指数和布雷图指数,分析不同月份及生境密度指数变化趋势.经研究,2013年各指数相对较低,各年不同指数随月份变化趋势明显,6～9月为指数相对较高的月份.居民区和城乡结合部容器指数最高,分别为10.86％和9.84％.总体上,宁波市以白纹伊蚊为媒介暴发蚊媒传染病疫情的风险较低,但应加强对7～9月的风险监测,环境条件对密度指数影响较大,应重视在6月份开展爱国卫生运动及对人员密集场所的环境消杀工作,加强宣传教育.     

Reciprocal congenics defining individual quantitative trait Loci for sedative/hypnotic sensitivity to ethanol

BACKGROUND: We have identified four major genes or quantitative trait loci (QTLs) that determine duration of loss of righting reflex (LORR), induced by sedative doses of ethanol: Lore1, Lore2, Lore4, and Lore5. Together these genes explain more than 50% of the phenotypic variance for sensitivity to the sedative/hypnotic effects of ethanol between the Inbred Long Sleep (ILS) and Inbred Short Sleep (ISS) strains of mice. The derivation of these strains is reviewed here. METHODS: Each QTL has been bred onto the opposite background (ILS or ISS) through 10 rounds of backcrossing by using QTL-marker-assisted counter selection to produce reciprocal congenic strains. Mice were genotyped for markers that flanked each of the QTLs. Selection for the donor at the desired QTL, and against donor markers at the other four QTLs, allowed rapid fixation of the genetic background. Phenotypic assessment in the ISS-recipient congenic strains was conducted throughout the backcross. RESULTS: By the N5 generation, phenotypic assessments failed to detect significant effects in some sublines; these sublines were discarded and positive lines split to create new replicate sublines. In the N10, all sublines retained the phenotypic difference between heterozygotes and ISS homozygotes; however, the expected additive effect was not found in the Lore1 congenics. On the ILS background, each Lore was captured, as shown by the expected differential LORR. Two strains on the ILS background, and one on the ISS, exhibited the differential effect on blood ethanol concentration associated with the donor strain. CONCLUSIONS: Congenic strains represent an important resource for confirmation of previously identified QTLs, for identification and mapping of additional phenotypes, and for exclusion of candidate genes. QTL-marker-assisted selection rapidly stabilized the genetic background within four generations (based on phenotypic assessments); however, phenotypic selection during the backcrossing to generate congenic strains did not contribute to the successful capture of the ISS QTLs.     

Effects of social cues on GnRH-I, GnRH-II, and reproductive physiology in female house sparrows (Passer domesticus)

In all vertebrates, at least two forms of gonadotropin-releasing hormone (GnRH) are present: GnRH-I and GnRH-II. GnRH-I directly influences the reproductive axis whereas the function of GnRH-II is less clear. The present experimental objectives were to determine the effect(s) of male social cues on the peripheral and neural responses of female house sparrows (Passer domesticus). We hypothesized that male breeding status would significantly influence the amount of immunoreactive GnRH-II in female house sparrow brains. In order to test this hypothesis, females were caged with a breeding male, a non-breeding male, or caged alone. The presence of breeding males did not significantly influence ovary development, luteinizing hormone, or estradiol levels, but male presence increased female body mass, and male presence and condition interacted to influence ovarian follicle size. Using immunocytochemistry, GnRH-I and GnRH-II immunoreactivity was measured in order to evaluate the neuroendocrine response to breeding status in males. When females were housed with breeding males, there were stable numbers of immunoreactive GnRH-I and -II cells but significantly lower amounts of immunoreactive GnRH-I fibre staining within the preoptic area compared to females housed with non-breeding males. Moreover, immunoreactive GnRH-II fibres in the preoptic area, ventromedial nucleus, and medial septum were significantly greater in females housed alone in chamber with non-breeding males. The data demonstrate that the GnRH system in songbirds is modulated by social context. These finding provide novel insight into the mechanisms involved with regulating avian reproductive physiology.     

Sergentomyia spp.: Breeding sites in vertisols and peri-domestic habitats in North West Ethiopia

Sand flies belonging to the genus Sergentomyia Franca & Parrot, 1920, are hematophagous insects feeding mostly on reptiles and birds, but some species feed also on mammals including humans. Sergentomyia spp. frequently comprise the vast majority of sand flies trapped along with Phlebotomus spp., the vectors of mammalian leishmaniasis. Within the framework of a project on the ecology and transmission of visceral leishmaniasis in Ethiopia, putative breeding sites of phlebotomine sand flies were studied. Large horizontal sticky traps (LHSTs) covered with sand fly-proof mesh were deployed over cracked vertisol and related habitats for up to 3 nights, and emerging sand flies were collected daily. Emergence traps (ETs) were also adapted to sample other putative breeding sites including tree trunks, termite mounds, rock piles and vertical river banks. Productive breeding sites were identified in the trunks and roots systems of trees, vertisol fields, cracks and burrows in vertisol dry river banks and termite mounds. Emerging flies were also collected form a stone wall and a rock pile situated inside a village. Significantly more Sergentomyia spp. were trapped in vertisols by ETs deployed over root system than in open fields. Similarly, more sand flies emerged from cracks in the vertisol in fallow Sorghum than in fallow sesame fields. Productive breeding sites were characterized by stable micro-climatic conditions. Species composition of emerging sand flies varied with habitat, season and geographical location.