博尔纳病病毒对BALB/c小鼠感染性检测

目的分析博尔纳病病毒（Borna disease virus,BDV）H1766株对BALB/c小鼠的感染性。方法选择病毒滴度为2.0×107FFU/ml的BDV病毒液分别对新生和成年BALB/c小鼠进行脑内接种,并用相同病毒液对原代培养的新生BALB/c小鼠脑细胞进行接种。经过一定时间的病毒作用后分别提取总RNA,采用巢式RT-PCR方法检测BDV-p40基因,并通过免疫组化方法检测脑内接种脑组织中BDV-P40蛋白。结果脑内接种病毒的小鼠脑组织中可以检测到BDV-p40基因和BDV-P40蛋白,培养的小鼠脑细胞中可以检测到BDV-p40基因。结论BDVH1766株可以感染新生和成年的BALB/c小鼠。     

博尔纳病病毒pEGFP-p24基因重组质粒的构建及鉴定

构建博尔纳病病毒pEGFP-p24基因重组表达质粒。通过PCR方法扩增获得博尔纳病痛毒p24基因的完整序列,将此片段定向克隆到pEGFP-N1载体多克隆位点区,筛选重组阳性菌株,提取重组质粒,利用PCR方法和核酸序列测定验证重组质粒构建的正确性。PCR及核酸序列测定证明博尔纳病病毒pEGFP-p24基因重组表达质粒构建成功。构建的重组质粒将为研究博尔纳病病毒p24基因在真核细胞中的功能和作用提供实验依据。     

On the nature of lengthy nucleotide repeated sequences in genomes of prokaryotic organisms

The whole genomic analysis in silico of 64 free-living prokaryotic species has been performed to determine the number, length, distribution, and localization of directed and inverted intragenomic repeated sequences (LRS). Three main types of lengthy (≥500 bp) repeated sequences were revealed: (a) associated with ribosomal RNA genes; (b) with copies of protein coding genes; (c) with IS-elements and genes encoding the hypothetical transposases. Lengthy repeated sequences related to transposases comprise 50 to 95% of the total number of LRS depending on the species. Intragenomic LRS associated with transposases and IS-elements can reflect the recombination potential of different prokaryotic species determining the capability for adaptive gene rearrangements as well as the cell capacity for integration of foreign genes acquired through horizontal transfer paths.     

Isolation and characterization of polymorphic microsatellite loci for the horn fly, Haematobia irritans (L.) (Diptera: Muscidae)

The horn fly, Haematobia irritans (L.) (Diptera: Muscidae), is a cosmopolitan livestock pest that has caused a great negative impact on the animal production sector throughout the world. Here, we describe 10 polymorphic microsatellite loci isolated from H. irritans. The number of alleles found ranged from two to eight per locus and the expected heterozygosity from 0.1421 to 0.7702. These loci are potentially useful for the fine-scale genetic characterization of horn fly populations and provide fundamental information for pest management and planning of control programs.     

Expression of estrogen receptor (ER) -α and -βtranscripts in the neonatal and adult rat cerebral cortex, cerebellum, and olfactory bulb

INTRODUCTIONEstrogen has been known to exert extensive effects via estrogen receptor (ER) on diverse physio-logical and develoPmental functions of the brain[1,2]. It has been observed that the distribution ofthe classical ER subtype-a (ERa) and the recentlycharacterized novel ER subtype--fi (ERg), and theirexpression patterns (ERcr/ERfi) vary greatly amongvarious brain regions[1, 3]. These evidences suggestthat each ER subtype may play a different role inestrogen's effects on the br…     

Collection of Arabidopsis thalianaMutants with Altered Sensitivity to Oxidative Stress Inductors

Selective systems for screening Arabidopsis thaliana(L.) Heynh. mutants with altered sensitivity to the oxidative stress (OS) inductors norflurazon (NF), acifluorfen (AF), and plumbagin (PB) were developed and a collection of 28 mutants was obtained. Dwarf and necrotic forms predominated among the NF-tolerant mutants, while pigment mutants and those with changed root morphology prevailed among the AF-tolerant and PB-sensitive mutants, respectively. Genetic and biochemical analysis of certain mutants was performed; quantitative and qualitative changes in the content of superoxide dismutase and peroxidase isoforms have been revealed. These data, complemented by the data on the cross-tolerance (sensitivity) of the mutants to paraquat, indicate a correlation between tolerance to the OS inductors and the functions of antioxidant systems.     

UV-induced DNA degradation in Aspergillus nidulans cells]

UV-induced DNA degradation was studied in mycellial cells of Aspergillus nidulans wild type and several uvs mutants. It was shown to be an enzymatic specific process which possibly reflects the excision of pyrimidine dimers from UV-damaged DNA. Inhibition of DNA degradation by caffeine and 2,4-dinitrophenol shows the connection between degradation and repair of DNA. Two ways of DNA degradation were found in A. nidulans cells, one of them being glucose dependent and the other--glucose independent. The dependence of DNA degradation on protein synthesis before and after UV-irradiation was demonstrated. The scheme of ways of DNA degradation and its genetic control were suggested on the basis of uvs mutations effect on UV-induced DNA degradation.     

Carrion flies of forensic interest: a study of seasonal community composition and succession in Lisbon,Portugal

Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal.