伊蚊3HKT基因RNAi载体构建及口服对伊蚊的致死作用

构建伊蚊3HKT基因的RNAi表达载体pMaa7IR/3HKTIR,转化莱茵衣藻,将得到的转基因藻株喂饲伊蚊幼虫.结果表明,3HKT RNAi转基因藻株对伊蚊有一定的致死作用.伊蚊是登革热、寨卡病毒病、黄热病、基孔肯雅病的媒介昆虫;微藻是蚊子幼虫天然食物,在自然界广泛存在,并且小球藻、衣藻等可大规模生产、生产成本低廉,...     

Dual infection with HIV and malaria fuels the spread of both diseases in sub-Saharan Africa

Mounting evidence has revealed pathological interactions between HIV and malaria in dually infected patients, but the public health implications of the interplay have remained unclear. A transient almost one-log elevation in HIV viral load occurs during febrile malaria episodes; in addition, susceptibility to malaria is enhanced in HIV-infected patients. A mathematical model applied to a setting in Kenya with an adult population of roughly 200,000 estimated that, since 1980, the disease interaction may have been responsible for 8,500 excess HIV infections and 980,000 excess malaria episodes. Co-infection might also have facilitated the geographic expansion of malaria in areas where HIV prevalence is high. Hence, transient and repeated increases in HIV viral load resulting from recurrent co-infection with malaria may be an important factor in promoting the spread of HIV in sub-Saharan Africa.     

美洲棘蓟马体内共生菌Wolbachia的wsp基因分子检测及系统发育分析

【目的】对美洲棘蓟马体内共生菌Wolbachia进行分子生物学鉴定,确定该蓟马体内Wolbachia的进化位置,为进一步探讨Wolbachia对其生殖作用的调控机制提供理论依据。【方法】以wsp基因为目的基因,对美洲棘蓟马体内的共生菌Wolbachia进行特异性扩增和测序,使用Clustal X 1.83软件对所得DNA序列进行比对;在MEGA 4.0软件中采用邻接法对Wolbachia的系统发育关系进行分析。【结果】利用wsp基因的特异性引物从美洲棘蓟马体内扩增出了632 bp的Wolbachia的wsp基因片段(GenBank登录号为JN315668),580 bp的Wolbachia A群的wsp基因片段和405 bp的Mel亚群的wsp基因片段。系统发育分析结果表明,美洲棘蓟马体内的Wolbachia与黑腹果蝇亲缘关系较近。【结论】美洲棘蓟马体内感染的Wolbachia属于A群Mel亚群。     

天维菌素处理埃及伊蚊幼虫的转录组学分析

为探索新型大环内酯类杀虫剂天维菌素对蚊虫防控的应用前景，进一步了解天维菌素对蚊虫的作用机制，本研究利用转录组测序技术研究埃及伊蚊幼虫参与药物代谢及靶标等生物学过程的基因。利用高通量测序获取给药前后埃及伊蚊的差异表达基因，进一步进行Gene Ontology（GO）及KEGG富集分析，并利用Real-time Quantitative PCR（rt-qPCR）验证目标基因表达情况。结果显示，与对照组相比，天维菌素处理后埃及伊蚊幼虫中有2 647个基因差异显著表达，其中上调基因有697个，下调表达的基因有1 950个。Gene Ontology分析显示，测序基因主要注释到细胞过程、代谢过程、膜、结合和催化活性等功能类。KEGG通路主要富集在药物代谢、免疫应答、生物合成以及消化与吸收等过程。选取GST-1，EST2等6个目标基因进行rt-qPCR验证，表达水平与测序结果一致。     

北京地区8种斑螟Wolbachia的感染检测及其wsp基因序列分析

采用PCR扩增法,对北京地区8种斑螟亚科昆虫：圆斑栉角斑螟、红云翅斑螟、曲小锯齿斑螟、叉斑螟、亮雕斑螟、富泽云斑螟、微红梢斑螟和牙梢斑螟进行了Wolbachia的wsp基因分子检测;结果发现,在富泽云斑螟、微红梢斑螟和牙梢斑螟体内存在Wolbachia感染,所得的wsp基因序列分别为590,600和613 bp。对序列进行系统发育分析,结果发现富泽云斑螟体内感染的Wolbachia属于B大组的Btab2组类群,而微红梢斑螟和牙梢斑螟体内感染的Wolbachia属于A大组。     

A synthetic maternal-effect selfish genetic element drives population replacement in Drosophila

One proposed strategy for controlling the transmission of insect-borne pathogens uses a drive mechanism to ensure the rapid spread of transgenes conferring disease refractoriness throughout wild populations. Here, we report the creation of maternal-effect selfish genetic elements in Drosophila that drive population replacement and are resistant to recombination-mediated dissociation of drive and disease refractoriness functions. These selfish elements use microRNA-mediated silencing of a maternally expressed gene essential for embryogenesis, which is coupled with early zygotic expression of a rescuing transgene.     

广东省桔小实蝇种群感染Wolbachia的分子检测

沃尔巴克氏体(Wolbachia)是一类广泛存在于节肢动物生殖器官内的共生细菌.利用Wolbachia表面蛋白wsp基因的1对通用引物81F和691R,对广东省桔小实蝇(Bactrocera dorsalis)地理种群感染Wolbachia状况进行PCR检测.结果表明,桔小实蝇珠海地理种群有1个个体感染Wolbachia,其他种群均未见感染;广东省桔小实蝇种群感染Wolbachia的概率为0.4%.     

Infection of Wolbachia in Trichogramma cacoeciae

Wolbachia is a symbiotic bacterium that alters reproductive behavior of numerous arthropods.It is the most advanced way to study phylogeny and classification based on sequences of the wsp gene. The presence of Wolbachia in a lab strain of the thelytokous Trichogramma cacoeciae was firstly identified based on amplification and sequencing part of the wsp gene. Aligned the resulting sequence with the published ones,the phylogenetic relationships among Wolbachia which was found in T. cacoeciae, T. dendrolimi and other insects were established. The Wolbachia that found in T. cacoeciae and in T. dendrolimi belong to the Kue group and the Pip group, respectively.     

管氏肿腿蜂感染Wolbachia的分子检测

Wolbachia是一类在节肢动物中广泛感染的胞内共生菌,为了解Wolbachia在管氏肿腿蜂体内的感染情况,采用Wolbachia的通用引物、A大组特异性引物和B大组特异性引物对管氏肿腿蜂体内Wolbachia的wsp基因进行PCR扩增及序列测定,所获得的基因片段分别命名为wSgu、wSguA和wSguB,长度分别为620、572bp和463bp。基因序列分析表明wSgu与wSguB序列间碱基差异较大,同源性仅为60%。系统发育分析表明该寄生蜂感染了A大组的Wolbachia,但对于该寄生蜂是否也感染了B大组的Wolbachia尚待确定。     

Disease tolerance as a defense strategy

The immune system protects from infections primarily by detecting and eliminating the invading pathogens; however, the host organism can also protect itself from infectious diseases by reducing the negative impact of infections on host fitness. This ability to tolerate a pathogen's presence is a distinct host defense strategy, which has been largely overlooked in animal and human studies. Introduction of the notion of "disease tolerance" into the conceptual tool kit of immunology will expand our understanding of infectious diseases and host pathogen interactions. Analysis of disease tolerance mechanisms should provide new approaches for the treatment of infections and other diseases.     

肉鸽新城疫的诊治报告

新城疫病毒(Newcastle disease virus)属于副粘病毒科副粘病毒属禽副粘病毒I型(A/PMV-1)。新城疫(ND)是一种高度接触性传染病,鸡、火鸡、鸽以及野禽均易患。1926年Kraneveld氏首先发现于印度尼西亚的巴塔维亚,同年doyle氏发现于英国的新城而故名,新城疫(ND)1迄今仍在世界广泛流行。邯郸县某肉鸽养殖场暴发一种以神经症状为主,腹泻,死亡率极高的传染病。经病原分离与鉴定,确诊为鸽新城疫,经鸡高免卵黄抗体治疗收到了良好效果。     

Using Markov Decision Processes to define an adaptive strategy to control the spread of an animal disease

A strategy to control an animal disease within an area is often based on one or more actions systematically implemented. In this paper, we illustrate how to use a Markov Decision Process (MDP) to compute an adaptive strategy depending on the pathogen spread within a group of farmers with only one decision-maker for the group. The objective at the group level is to decrease the cost of the disease and its control. Status for each farm is assumed to be exactly known each year by the decision-maker. Possible actions each year are Doing nothing or Vaccinating. The computed MDP policy results in a non-systematic vaccination. Although the objective is only based on the total costs, the computed MDP policy reduces the prevalence, that is the amount of infected herds, compared to a systematically Doing nothing strategy.     

Wolbachia对山楂叶螨实验种群生长发育和繁殖的影响

Wolbachia是一种共生菌,可在多种叶螨寄主中引起细胞质不亲和及适合度改变,影响寄主的生物学特性。为了明确感染Wolbachia对山楂叶螨种群生长发育和繁殖的影响,本试验采用生命表法系统观察了山楂叶螨感染种群和未感染种群的生物学,分析感染Wolbachia对其生殖参数的影响。结果显示:感染种群产卵前期比未感染种群延长了约0.69d,产卵量降低了16.84%,而对其性比没有显著影响。感染种群在25℃从卵发育到成螨平均需要(14.21±0.11)d,比未感染种群(13.25±0.08)d延长了将近1d。感染种群数量增长1倍,需要的时间为5.7346d,未感染种群仅需要5.1322d;感染种群平均每经过1d增长为原数量的1.1285倍,未感染种群则为原数量的1.1446倍。表明感染Wolbachia的山楂叶螨种群生殖力下降,各虫态的发育历期延长,种群发展速率下降。     

应用基因分型技术研究牛结核分枝杆菌分子流行病学

牛分枝杆菌是引起牛结核病(bTB)的病原体,侵染宿主广泛,可感染多种家畜和野生动物,对人类和动物健康构成巨大危害。随着多年不懈的研究,有关分枝杆菌分子流行病学的知识积累不断增加。作者对近年来应用新的基因分型技术研究牛结核分枝杆菌分子流行病学方面的一些研究进展。这些技术包限制性片段长度多态性分析(RFLP)、PCR介导的间隔区寡核苷酸分析(spoligotyping)、数目可变串联重复位点(VNTR)等。主要用于对人、牛、家畜以及野生动物的结核病分子流行病学进行分析和监测。另外,还利用一系列敏感的基于PCR的技术从分枝杆菌杆菌复合体(NTM)中对菌型进行鉴别。对分枝杆菌感染分子流行病学的全面了解,有助于对本病扩散传播机制的深入研究。可为制定科学防治结核病的措施做出贡献。     

Wolbachia在灰飞虱群体中的传染

灰飞虱(Laodelphaxstriatellus)能传播水稻条纹叶枯病,是我国重要的水稻害虫。Wolbachia是存在于多种昆虫生殖器官的一类共生菌,它可通过在宿主群体中引起细胞质不亲和性(CI)而给宿主带来生殖优势。通过对灰飞虱体内Wolbachia感染率的测定,监测Wolbachia在灰飞虱群体中的扩散趋势从而为媒介昆虫-共生菌技术(Vector-Insect-SymbiontTech-nology,VIST)这一防治手段提供研究基础。     

Wolbachia enhance Drosophila stem cell proliferation and target the germline stem cell niche

Wolbachia are widespread maternally transmitted intracellular bacteria that infect most insect species and are able to alter the reproduction of innumerous hosts. The cellular bases of these alterations remain largely unknown. Here, we report that Drosophila mauritiana infected with a native Wolbachia wMau strain produces about four times more eggs than the noninfected counterpart. Wolbachia infection leads to an increase in the mitotic activity of germline stem cells (GSCs), as well as a decrease in programmed cell death in the germarium. Our results suggest that up-regulation of GSC division is mediated by a tropism of Wolbachia for the GSC niche, the cellular microenvironment that supports GSCs.     

Role of delayed nuclear envelope breakdown and mitosis in Wolbachia-induced cytoplasmic incompatibility

The bacterium Wolbachia manipulates reproduction in millions of insects worldwide; the most common effect is cytoplasmic incompatibility (CI). We found that CI resulted from delayed nuclear envelope breakdown of the male pronucleus in Nasonia vitripennis. This caused asynchrony between the male and female pronuclei and, ultimately, loss of paternal chromosomes at the first mitosis. When Wolbachia were present in the egg, synchrony was restored, which explains suppression of CI in these crosses. These results suggest that Wolbachia target cell cycle regulatory proteins. A striking consequence of CI is that it alters the normal pattern of reciprocal centrosome inheritance in Nasonia.     

Vaccination for disease.

Recombinant virus vaccines that express a limited number of epitopes are currently being developed to prevent disease by changing the relative balance between viral spread and the immune response. Some circumstances, however, were found in infections with a noncytopathic virus in which vaccination caused disease; sensitive parameters included the genetic background of the host, the time or dose of infection, and the constituents of the vaccine. Thus, immunopathologic damage by T cells may be an unwanted consequence of vaccination with the new types of peptide or recombinant vaccines that are being investigated for the human immunodeficiency viruses and other pathogens.     

未感染概率为一般函数的离散S-I-R模型

研究了一个离散S-I-R传染病模型,其中未感染概率为关于被感染人群的一般函数.建立了模型的基本再生数,得到了平衡点的存在性和稳定性只依赖于此再生数.此外,还得到了系统一致持久和全局渐近稳定的条件.模型的数学结论表明种群密集是疾病传播的原因,提高医疗技术有利于疾病控制.     

Wolbachia在短管赤眼蜂和拟澳洲赤眼蜂种间的水平传递

用米蛾卵作为短管赤眼蜂和拟澳洲赤眼蜂共寄生的寄主,实现Wolbachia在赤眼蜂种间的水平传递.对Wolbachia的wsp基因进行PCR检测,结果表明,这4头处女雌蜂体内有Wolbachia的存在,且在由这4头处女雌蜂为单系所建立第1～5代拟澳洲赤眼蜂群体内,Wolbaccha的检测均为阳性;wsp基因序列比对和同源性分析结果表明,拟澳洲赤眼蜂和短管赤眼蜂体内Wolbachia的wsp基因序列完全一致.证明未感染Wolbachia的拟澳洲赤眼蜂和感染Wolbachia的短管赤眼蜂在同一米蛾卵体内共同发育时,Wolbachia能从供体短管赤眼蜂成功地水平传递到新宿主拟澳洲赤眼蜂体内,并能在新宿主体内垂直传递5代.