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J Sep Sci ; 43(1): 258-270, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654552


Microfluidic chip electrophoresis has been widely employed for separation of various biochemical species owing to its advantages of low sample consumption, low cost, fast analysis, high throughput, and integration capability. In this article, we reviewed the development of four different modes of microfluidics-based electrophoresis technologies including capillary electrophoresis, gel electrophoresis, dielectrophoresis, and field (electric) flow fractionation. Coupling detection schemes on microfluidic electrophoresis platform were also reviewed such as optical, electrochemical, and mass spectrometry method. We further discussed the innovative applications of microfluidic electrophoresis for biomacromolecules (nucleic acids and proteins), biochemical small molecules (amino acids, metabolites, ions, etc.), and bioparticles (cells and pathogens) analysis. The future direction of microfluidic chip electrophoresis was predicted.

Sci Rep ; 6: 21296, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26878829


Ascoviruses are insect-specific large DNA viruses that mainly infect noctuid larvae, and are transmitted by parasitoids in the fields. Heliothis virescens ascovirus 3h (HvAV-3h) has been recently isolated from Spodoptera exigua, without parasitoid vector identified previously. Here we report that Microplitis similis, a solitary endoparasitoid wasp, could transmit HvAV-3h between S. exigua larvae in the laboratory. When the female parasitoid wasp acquired the virus and served as a vector, the period of virion viability on the ovipositor was 4.1 ± 1.4 days. Infected host larvae were still acceptable for egg laying by parasitoids, and the parasitoids thereafter transmitted virus to healthy hosts. Virus acquisition occurred only from donor hosts between 3 and 9 days post infection. The peak of virus acquisition (80.9 ± 6.3%) was found when M. similis wasps oviposited in larvae that had been inoculated with the virus 7 days previously. When virus infection of the host took place during the life cycle of the parasitoid wasp, it caused 1- to 4-day-old immature parasitoids death in the host, whilst a small proportion of 5- to 6-day-old and the majority of 7-day-old parasitoids larvae survived from the virus-infected hosts. Viral contamination did not reduce the life span or fecundity of female M. similis.

Ascoviridae/fisiologia , Spodoptera/parasitologia , Spodoptera/virologia , Viroses/transmissão , Vespas/parasitologia , Vespas/virologia , Animais , Feminino , Interações Hospedeiro-Parasita , Insetos Vetores , Larva/parasitologia , Larva/virologia , Estágios do Ciclo de Vida , Masculino , Oviposição , Temperatura Ambiente
J Invertebr Pathol ; 122: 40-3, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25149038


The complete genome sequence of Heliothis virescens ascovirus 3f (HvAV-3f) was obtained. The HvAV-3f genome has a circular genome of 198,157bp with a G+C content of 46.0%, and encodes 190 open reading frames (ORFs) longer than 69 amino acids. Two major homologous regions (hrs) and 29 'baculovirus repeat ORFs' (bro) were found in the genome. BLAST analyses revealed that three HvAV-3f genes were homologous to that of lepidopteran insects. Nine ORFs were unique to HvAV-3f, in which two ORFs showed significant levels of similarity to genes that have not been previously described for ascoviruses in the Genbank database.

Ascoviridae/genética , DNA Viral/genética , Genoma Viral/genética , Zea mays/virologia , Animais , DNA Viral/análise , Larva/virologia , Análise de Sequência de DNA , Estados Unidos
PLoS One ; 8(12): e85704, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24386488


Ascoviruses are double-stranded DNA viruses that are pathogenic to lepidopteran hosts, particularly noctuid larvae. Infection of a larva is characterized by retarded growth, reduced feeding and yellowish body color. In this paper, we reported the growth and development of three major agricultural noctuid insect pests, Helicoverpa armigera (Hübner), Spodoptera exigua (Hübner) and Spodoptera litura (Fabricius), infected with Heliothis virescens ascovirus 3h (HvAV-3h). Using 10-fold serial dilutions (0 to 7) of HvAV-3h-containing hemolymph to infect S. litura larvae, we found no significant difference in larval mortalities from 0 to 10(3)-fold dilutions; however, significant differences were observed at 10(4)-fold dilution and above. Using a 10-fold dilution of HvAV-3h-containing hemolymph to infect H. armigera, S. exigua and S. litura larvae, we found that the growth and development were significantly affected. All infected larvae could not pupate; the survival times of treated H. armigera, S. litura and S. exigua larvae were significantly longer than untreated control larvae. Body weight showed significant difference between treated and untreated control group from day 1 after inoculation in H. armigera and S. exigua, but day 2 in S. litura. Additionally, food intake also showed significant difference between treated and untreated control group from day 2 after inoculation in H. armigera and S. litura, but day 3 in S. exigua.

Ascoviridae/metabolismo , Lepidópteros/virologia , Animais , Ascoviridae/patogenicidade , Hemolinfa/virologia , Larva/genética , Larva/metabolismo , Lepidópteros/metabolismo , Especificidade da Espécie
PLoS One ; 7(7): e40225, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22792245


Insect-specific ascoviruses with a circular genome are distributed in the USA, France, Australia and Indonesia. Here, we report the first ascovirus isolation from Spodoptera exigua in Hunan, China. DNA-DNA hybridization to published ascoviruses demonstrated that the new China ascovirus isolate is a variant of Heliothis virescens ascovirus 3a (HvAV-3a), thus named HvAV-3h. We investigated the phylogenetic position, cell infection, vesicle production and viral DNA replication kinetics of HvAV-3h, as well as its host-ranges. The major capsid protein (MCP) gene and the delta DNA polymerase (DNA po1) gene of HvAV-3h were sequenced and compared with the available ascovirus isolates for phylogenetic analysis. This shows a close relationship with HvAV-3g, originally isolated from Indonesia, HvAV-3e from Australia and HvAV-3c from United States. HvAV-3h infection induced vesicle production in the SeE1 cells derived from S. exigua and Sf9 cells derived from S. frugiperda, resulting in more vesicles generated in Sf9 than SeE1. Viral DNA replication kinetics of HvAV-3h also demonstrated a difference between the two cell lines tested. HvAV-3h could readily infect three important insect pests Helicoverpa armigera (Hübner), Spodoptera exigua (Hübner) and Spodoptera litura (Fabricius) from two genera in different subfamilies with high mortalities.

Ascoviridae/genética , Filogenia , Spodoptera/virologia , Replicação Viral , Animais , Ascoviridae/classificação , Ascoviridae/isolamento & purificação , Ascoviridae/ultraestrutura , DNA Viral/genética , Cinética , Células Sf9 , Proteínas Virais/genética , Tropismo Viral
Huan Jing Ke Xue ; 28(7): 1567-72, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17896427


Objective of this study was to understand the spatial pattern of soil properties and topographic factors and their relationships in a small watershed. We used classical statistical coupling with geo-statistical theory to characterize and compare the spatial variability of soil mineral N and topographic factors in the wind-water erosion crisscross region on the Loess Plateau. The results show that: 1) The nitrate's variable extent is strong while other properties are moderate variability, and the impacts of soil types, land uses on variable extent are significant. 2) All properties have different spatial dependence extent in the study area. Ammonium and elevation are strong spatial dependence while nitrate, slope gradient and slope aspect are moderate spatial dependence. 3) The analysis results of fractal dimension and spatial heterogeneity proportion are coherent, and the decreased sequence is: nitrate (1.9826) > slope aspect (1.9767) > slope angle (1.9420) > ammonium (1.8791) > elevation (1.7461). 4) In 0 degrees C/90 degrees C, 45 degrees C/135 degrees C aspects, nitrate is isotropy while elevation is anisotropy, and others are weak anisotropy. 5) Ammonium and elevation have strong spatial autocorrelation while nitrate has not. There exist extremely notable positive correlations between nitrate and ammonium, slope gradient and aspect, and the negative correlations between ammonium, slope aspect and elevation, which indicate that the distribution of ammonium and slope gradient have elevation gradients.

Água Doce/análise , Sedimentos Geológicos/análise , Nitrogênio/análise , Solo/análise , Altitude , China , Monitoramento Ambiental , Água Doce/química , Sedimentos Geológicos/química , Nitrogênio/química , Compostos Orgânicos/análise , Movimentos da Água , Vento