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Zhuo K.,South China Agricultural University | Cui R.,South China Agricultural University | Ye W.,United Road Services | Luo M.,South China Agricultural University | And 4 more authors.
Zootaxa | Year: 2010

Aphelenchoides fujianensis n. sp. is described and illustrated from a dead Pinus massoniana based on morphology and molecular analyses of the near-full-length small subunit rDNA gene and partial cytochrome oxidase subunit I of mitochondrial DNA. This new species belongs to the Group 3 of Aphelenchoides species sensu Shahina with star-shaped tail terminus and is characterised by a relatively long body (653-843 μm in the male and 803-941 μm in the female) and four lateral incisures in the lateral field. The male has relatively large spicules (24-30 μm). The female has elongate postvulval uterine sac (extending ca 32-44% of vulva-anus distance), usually with sperms. Both male and female have star-shaped mucro. It is distinguished from other species by postvulval uterine sac length, a and c ratios, and spicule size and shape. Molecular analysis reveals that this species has unique 18S and mt-DNA sequences, and is closest to Aphelenchoides besseyi in dendrograms inferred using both markers. The identification codes of OEPP/EPPO for A. fujianensis n. sp. are: A1-B2-C1-D1/3-E1-F1/2. © 2010 Magnolia Press. Source

Wu Y.,China Agricultural University | Wu Y.,Chinese Academy of Sciences | Mcpheron B.A.,Pennsylvania State University | Wu J.-J.,Guangdong Entry Exit Inspection and Quarantine Bureau | Li Z.-H.,China Agricultural University
Insect Science | Year: 2012

The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), has been the subject of worldwide quarantine and management efforts due to its widespread agricultural impact and potential for rapid range expansion. From its presumed native distribution in India, this species has spread throughout the hot-humid regions of the world. We provide information that reveals population structure, invasion history and population connectivity from 23 locations covering nine countries based on DNA sequences of the mitochondrial cytochrome oxidase I (COI) gene. Forty-two polymorphic sites were described among 38 haplotypes. The most common haplotype, H1, was observed in 73% of the samples distributed among all populations. Highest genetic diversity was seen within populations, and no isolation-by-distance was detected. The western regions (Nepal, Bangladesh, Thailand, Burma and China-west) showed higher haplotype diversity than eastern regions (China-east). China-Yunnan showed highest levels of genetic diversity in China. Haplotype diversity decreased with longitude from west to east. Together, these analyses suggest that B. cucurbitae has expanded from west to east within a limited geographic scale and recently invaded China through Yunnan Province. © 2012 The Authors Journal compilation © Institute of Zoology, Chinese Academy of Sciences. Source

Lu X.,PLA Fourth Military Medical University | Li X.,Guangdong Entry Exit Inspection and Quarantine Bureau | Mo Z.,Guangzhou University | Jin F.,PLA Fourth Military Medical University | And 4 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2012

Both Chikungunya and Dengue virus belong to the acute arthropod-borne viruses. Because of the lack of specific symptoms, it is difficult to distinguish the two infections based on clinical manifestations. To identify and quantitatively detect Chikungunya and Dengue viruses, a real-time accelerated reverse-transcription-loop-mediated isothermal amplification (RT-LAMP) platform was developed, and 26-confirmed RNA samples, 42 suspects, and 18 healthy serum samples were evaluated by the method. The RT-polymerase chain reaction (PCR) and cDNA sequencing were used as references. The results showed that it could identify the Chikungunya and Dengue virus RNA correctly in all antibody-positive samples within 1 hour, without any cross-reactions. The virus load of the positive samples was quantitatively detected with a turbidimeter. The sensitivity was 100% and specificity was 95.25%. The findings indicate that the RT-LAMP is an effective method for rapid quantity detection of Chikungunya virus and Dengue virus in serum samples with convenient operation, high specificity, and high sensitivity. Copyright © 2012 by The American Society of Tropical Medicine and Hygiene. Source

Li J.,Hunan University | Chen L.,Hunan University | Chen L.,Changsha Municipal Drainage Co. | Huang C.,Hunan University | And 5 more authors.
Analyst | Year: 2013

Anti-octachlorostyrene (OCS) antibody was derived from an immune rabbit preparation. An OCS immunosensor was constructed by immobilizing the anti-OCS antibody on a glassy carbon electrode coated with chitosan and gold nanoparticles (AuNPs, ∼5 nm, represented as AuNP05). Large-sized AuNPs (∼90 nm, represented as AuNP90) were used as the electrochemical label. The AuNP90-labeled OCS competes with the target OCS for the limited antibody molecules immobilized on the sensor surface. The amount of bound AuNP90 is inversely proportional to the OCS concentration. OCS was quantified based on the bound AuNP90 which was detected by differential pulse voltammetry (DPV), i.e. the AuNP90 was firstly electrooxidized in 0.1 M HCl to produce AuCl 4-, then the reduction current of AuCl4 - was detected. The immobilized AuNP05 increases the loading of anti-OCS antibody. Both the immobilized AuNP05 and the label AuNP90 amplify the sensor response. The proposed electrochemical immunosensor exhibits high selectivity, good storage stability, and high sensitivity with a linear range from 1 to 500 nM (R2 = 0.971) and a detection limit of 0.4 nM. © 2013 The Royal Society of Chemistry. Source

Lu X.,PLA Fourth Military Medical University | Li X.,Guangdong Entry Exit Inspection and Quarantine Bureau | Mo Z.,Guangzhou University | Jin F.,PLA Fourth Military Medical University | And 5 more authors.
Virus Genes | Year: 2014

A small-scale local chikungunya outbreak occurred in a Guangdong village of southern China in October 2010. The five chikungunya viruses (CHIKV) isolated from the epidemic and three other imported cases obtained from the same period were sequenced and analyzed for phylogenesis. The results demonstrated that all of the eight sequences were clustered in the Eastern, Central, Southern, and African group. However, the local strains and imported isolates showed different sequence variations. A226V in E1 gene and V264A in E2 gene were detected in all three imported isolates, the unique substitutions S250P in E1 gene and H313Y in E2 genes could be observed in four of the five local strains. These significant variations might be some of the causes for the outbreak. It would be an important event for CHIKV to have mutated adaption to the local mosquitoes in China, Aedes albopictus and Aedes aegypti. © Springer Science+Business Media 2013. Source

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