Genetic diversity and distribution of a distinct strain of Chili leaf curl virus and associated betasatellite infecting tomato and pepper in Oman.

Science.gov (United States)

Khan, Akhtar J; Akhtar, Sohail; Al-Zaidi, Amal M; Singh, Achuit K; Briddon, Rob W

2013-10-01

Tomato and pepper are widely grown in Oman for local consumption. A countrywide survey was conducted during 2010-2011 to collect samples and assess the diversity of begomoviruses associated with leaf curl disease of tomato and pepper. A virus previously only identified on the Indian subcontinent, chili leaf curl virus (ChLCV), was found associated with tomato and pepper diseases in all vegetable grown areas of Oman. Some of the infected plant samples were also found to contain a betasatellite. A total of 19 potentially full-length begomovirus and eight betasatellite clones were sequenced. The begomovirus clones showed >96% nucleotide sequence identity, showing them to represent a single species. Comparisons to sequences available in the databases showed the highest levels of nucleotide sequence identity (88.0-91.1%) to isolates of the "Pakistan" strain of ChLCV (ChLCV-PK), indicating the virus from Oman to be a distinct strain, for which the name Oman strain (ChLCV-OM) is proposed. An analysis for recombination showed ChLCV-OM likely to have originated by recombination between ChLCV-PK (the major parent), pepper leaf curl Lahore virus and a third strain of ChLCV. The betasatellite sequences obtained were shown to have high levels of identity to isolates of tomato leaf curl betasatellite (ToLCB) previous shown to be present in Oman. For the disease in tomato Koch's postulates were satisfied by Agrobacterium-mediated inoculation of virus and betasatellites clones. This showed the symptoms induced by the virus in the presence of the betasatellite to be enhanced, although viral DNA levels were not affected. ChLCV-OM is the fourth begomovirus identified in tomato in Oman and the first in Capsicum. The significance of these findings is discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Tomato Leaf Curl New Delhi Virus: An Emerging Virus Complex Threatening Vegetable and Fiber Crops

Directory of Open Access Journals (Sweden)

Enrique Moriones

2017-09-01

Full Text Available The tomato leaf curl New Delhi virus (ToLCNDV (genus Begomovirus, family Geminiviridae represents an important constraint to tomato production, as it causes the most predominant and economically important disease affecting tomato in the Indian sub-continent. However, in recent years, ToLCNDV has been fast extending its host range and spreading to new geographical regions, including the Middle East and the western Mediterranean Basin. Extensive research on the genome structure, protein functions, molecular biology, and plant–virus interactions of ToLCNDV has been conducted in the last decade. Special emphasis has been given to gene silencing suppression ability in order to counteract host plant defense responses. The importance of the interaction with DNA alphasatellites and betasatellites in the biology of the virus has been demonstrated. ToLCNDV genetic variability has been analyzed, providing new insights into the taxonomy, host adaptation, and evolution of this virus. Recombination and pseudorecombination have been shown as motors of diversification and adaptive evolution. Important progress has also been made in control strategies to reduce disease damage. This review highlights these various achievements in the context of the previous knowledge of begomoviruses and their interactions with plants.

Tomato yellow leaf curl virus can be acquired and transmitted by Bemisia tabaci (Gennadius) from tomato fruits

NARCIS (Netherlands)

Delatte, H.; Dalmon, A.; Rist, D.; Soustrade, I.; Wuster, G.; Lett, J.M.; Goldbach, R.W.; Peterschmitt, M.; Reynaud, B.

2003-01-01

The whitefly Bemisia tabaci is an insect pest causing worldwide economic losses, especially as a vector of geminiviruses such as Tomato yellow leaf curl virus (TYLCV). Currently, imported and exported tomato fruit are not monitored for TYLCV infection because they are not considered to represent a

Molecular characterization of two sweepoviruses from China and evaluation of the infectivity of cloned SPLCV-JS in Nicotiana benthamiana.

Science.gov (United States)

Bi, Huiping; Zhang, Peng

2012-03-01

Sweepoviruses are important begomoviruses that infect Ipomoea plants worldwide and cause sweet potato yield losses and cultivar decline. Two sweepoviruses, sweet potato leaf curl virus-Jiangsu (SPLCV-JS) and sweet potato leaf curl China virus-Zhejiang (SPLCCNV-ZJ), were cloned from diseased sweet potato plants collected in the Jiangsu and Zhejiang provinces of China. Sequence characterization and phylogenetic analysis demonstrated that both are typical monopartite begomoviruses and have close relationships to several reported SPLCV and SPLCCNV isolates, respectively, from Asian countries. Analysis of the protein alignments and subcellular localizations of the six SPLCV-JS proteins was also conducted to verify their putative functions. In Nicotiana benthamiana, an infectivity assay of the infectious SPLCV-JS clone resulted in mild symptoms and weak viral DNA accumulation. Interestingly, SPLCV-JS, together with a heterologous betasatellite DNA (tomato yellow leaf curl China virus isolate Y10 [TYLCCNV-Y10] DNA-β), showed a synergistic effect on enhanced symptom severity and viral DNA accumulation. This is the first reported infectious SPLCV clone.

Genome wide identification of cotton (Gossypium hirsutum)-encoded microRNA targets against Cotton leaf curl Burewala virus.

Science.gov (United States)

Shweta; Akhter, Yusuf; Khan, Jawaid Ahmad

2018-01-05

Cotton leaf curl Burewala virus (CLCuBV, genus Begomovirus) causes devastating cotton leaf curl disease. Among various known virus controlling strategies, RNAi-mediated one has shown potential to protect host crop plants. Micro(mi) RNAs, are the endogenous small RNAs and play a key role in plant development and stress resistance. In the present study we have identified cotton (Gossypium hirsutum)-encoded miRNAs targeting the CLCuBV. Based on threshold free energy and maximum complementarity scores of host miRNA-viral mRNA target pairs, a number of potential miRNAs were annotated. Among them, ghr-miR168 was selected as the most potent candidate, capable of targeting several vital genes namely C1, C3, C4, V1 and V2 of CLCuBV genome. In addition, ghr-miR395a and ghr-miR395d were observed to target the overlapping transcripts of C1 and C4 genes. We have verified the efficacy of these miRNA targets against CLCuBV following suppression of RNAi-mediated virus control through translational inhibition or cleavage of viral mRNA. Copyright © 2017 Elsevier B.V. All rights reserved.

Biology and interactions of two distinct monopartite begomoviruses and betasatellites associated with radish leaf curl disease in India

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Singh AK

2012-02-01

Full Text Available Abstract Background Emerging whitefly transmitted begomoviruses are major pathogens of vegetable and fibre crops throughout the world, particularly in tropical and sub-tropical regions. Mutation, pseudorecombination and recombination are driving forces for the emergence and evolution of new crop-infecting begomoviruses. Leaf curl disease of field grown radish plants was noticed in Varanasi and Pataudi region of northern India. We have identified and characterized two distinct monopartite begomoviruses and associated beta satellite DNA causing leaf curl disease of radish (Raphanus sativus in India. Results We demonstrate that RaLCD is caused by a complex of two Old World begomoviruses and their associated betasatellites. Radish leaf curl virus-Varanasi is identified as a new recombinant species, Radish leaf curl virus (RaLCV sharing maximum nucleotide identity of 87.7% with Tomato leaf curl Bangladesh virus-[Bangladesh:2] (Accession number AF188481 while the virus causing radish leaf curl disease-Pataudi is an isolate of Croton yellow vein mosaic virus-[India] (CYVMV-IN (Accession number AJ507777 sharing 95.8% nucleotide identity. Further, RDP analysis revealed that the RaLCV has a hybrid genome, a putative recombinant between Euphorbia leaf curl virus and Papaya leaf curl virus. Cloned DNA of either RaLCV or CYVMV induced mild leaf curl symptoms in radish plants. However, when these clones (RaLCV or CYVMV were individually co-inoculated with their associated cloned DNA betasatellite, symptom severity and viral DNA levels were increased in radish plants and induced typical RaLCD symptoms. To further extend these studies, we carried out an investigation of the interaction of these radish-infecting begomoviruses and their associated satellite, with two tomato infecting begomoviruses (Tomato leaf curl Gujarat virus and Tomato leaf curl New Delhi virus. Both of the tomato-infecting begomoviruses showed a contrasting and differential interaction with

Gene expression in response to Cotton Leaf Curl Virus infection in Gossypium hirsutum under variable environmental conditions

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Rehman Iqra

2017-01-01

Full Text Available Cotton Leaf Curl Disease (CLCuD is one of the threatening constrains of cotton production in Pakistan for which no adequate remedy is available until now. Local variety of Gossypium hirsutum (FH-142 was grown in field and infected naturally by CLCuV under variable range of temperature and humidity. Plants showed thickening of veins in lower leaf surface at 34°C and 60% relative humidity at 15days post infection (dpi and curling of leaf margins at 33°C with 58% relative humidity at 30dpi. Remarkable leaf darkening was observed with reduced boll formation at 45dpi at 26°C and 41% relative humidity. Enation developed, severe thickening and curling of leaves intensified and plants showed dwarf growth at 60dpi at 24°C with 52% relative humidity. PCR amplification of Rep associated gene confirmed the presence of CLCuD-associated begomovirus in the infected samples. Quantitative RT-PCR confirmed the amplification and differential expression of a number of pathogen stress responsive genes at different levels of temperature and humidity. This observation predicts that Cotton Leaf Curl Virus (CLCuV interacts with several host genes that are upregulated to make plants susceptible or suppress other genes to overcome host defense responses.

Genome organization of Tobacco leaf curl Zimbabwe virus, a new, distinct monopartite begomovirus associated with subgenomic defective DNA molecules.

Science.gov (United States)

Paximadis, M; Rey, M E

2001-12-01

The complete DNA A of the begomovirus Tobacco leaf curl Zimbabwe virus (TbLCZWV) was sequenced: it comprises 2767 nucleotides with six major open reading frames encoding proteins with molecular masses greater than 9 kDa. Full-length TbLCZWV DNA A tandem dimers, cloned in binary vectors (pBin19 and pBI121) and transformed into Agrobacterium tumefaciens, were systemically infectious upon agroinoculation of tobacco and tomato. Efforts to identify a DNA B component were unsuccessful. These findings suggest that TbLCZWV is a new member of the monopartite group of begomoviruses. Phylogenetic analysis identified TbLCZWV as a distinct begomovirus with its closest relative being Chayote mosaic virus. Abutting primer PCR amplified ca. 1300 bp molecules, and cloning and sequencing of two of these molecules revealed them to be subgenomic defective DNA molecules originating from TbLCZWV DNA A. Variable symptom severity associated with tobacco leaf curl disease and TbLCZWV is discussed.

Assessment of the genetic diversity of tomato yellow leaf curl virus.

Science.gov (United States)

Wan, H J; Yuan, W; Wang, R Q; Ye, Q J; Ruan, M Y; Li, Z M; Zhou, G Z; Yao, Z P; Yang, Y J

2015-01-26

The objective of the present study was to analyze the genetic diversity of tomato yellow leaf curl virus (TYLCV). Representative TYLCV sequences were searched in the National Center for Biotechnology Information database. Comprehensive analysis of TYLCV was performed using bioinformatics by examining gene structure, sequence alignments, phylogeny, GC content, and homology. Forty-eight representative TYLCV sequences were selected from 48 regions in 29 countries. The results showed that all TYLCV sequences were 2752-2794 nucleotides in length, which encoded 6 open reading frames (AV1, AV2, AC1, AC2, AC3, and AC4). GC content ranged from 0.41-0.42. Sequence alignment showed a number of insertions and deletions within these TYLCV sequences. Phylogenetic tree results revealed that the sequences were divided into 10 classes; homology of the sequences ranged from 72.8 to 98.6%. All 48 sequences contained the typical structure of TYLCV, including open reading frames and intergenic regions. These results provide a theoretical basis for the identification and evolution of the virus in the future.

Engineering resistance against Tomato yellow leaf curl virus via the CRISPR/Cas9 system in tomato

KAUST Repository

Mahfouz, Magdy M.

2017-12-22

CRISPR/Cas systems confer molecular immunity against phages and conjugative plasmids in prokaryotes. Recently, CRISPR/Cas9 systems have been used to confer interference against eukaryotic viruses. Here, we engineered Nicotiana benthamiana and tomato (Solanum lycopersicum) plants with the CRISPR/Cas9 system to confer immunity against the Tomato yellow leaf curl virus (TYLCV). Targeting the TYLCV genome with Cas9-single guide RNA at the sequences encoding the coat protein (CP) or replicase (Rep) resulted in efficient virus interference, as evidenced by low accumulation of the TYLCV DNA genome in the transgenic plants. The CRISPR/Cas9-based immunity remained active across multiple generations in the N. benthamiana and tomato plants. Together, our results confirmed the efficiency of the CRISPR/Cas9 system for stable engineering of TYLCV resistance in N. benthamiana and tomato, and opens the possibilities of engineering virus resistance against single and multiple infectious viruses in other crops.

Amplicon based RNA interference targeting V2 gene of cotton leaf curl Kokhran virus-Burewala strain can provide resistance in transgenic cotton plants

Science.gov (United States)

An RNAi based gene construct designated “C2” was used to target the V2 region of the cotton leaf curl virus (CLCuV) genome which is responsible for virus movement. The construct was transformed into two elite cotton varieties MNH-786 and VH-289. A shoot apex method of plant transformation using Agr...

Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

KAUST Repository

Brown, J.K.

2011-06-01

The genome of a new bipartite begomovirus Melon chlorotic leaf curl virus from Guatemala (MCLCuV-GT) was cloned and the genome sequence was determined. The virus causes distinct symptoms on melons that were not previously observed in melon crops in Guatemala or elsewhere. Phylogenetic analysis of MCLCuV-GT and begomoviruses infecting cucurbits and other host plant species indicated that its closest relative was MCLCuV from Costa Rica (MCLCuV-CR). The DNA-A components of two isolates shared 88.8% nucleotide identity, making them strains of the same species. Further, both MCLCuV-GT and MCLCuV-CR grouped with other Western Hemisphere cucurbit-infecting species in the SLCV-clade making them the most southerly cucurbit-infecting members of the clade to date. Although the common region of the cognate components of MCLCuV-GT and MCLCuV-CR, shared similar to 96.3% nucleotide identity. While DNA-A and DNA-B components of MCLCuV-GT were less than 86% nucleotide identity with the respective DNAA and DNA-B common regions of MCLCuV-CR. The late viral genes of the two strains shared the least nt identity (<88%) while their early genes shared the highest nt identity (>90%). The collective evidence suggests that these two strains of MCLCuV are evolutionarily divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade. (C) 2011 Elsevier B.V. All rights reserved.

Recent evolution of a novel begomovirus causing tomato leaf curl disease in the Al-Batinah region of Oman.

Science.gov (United States)

Khan, Akhtar J; Akhtar, Sohail; Singh, Achuit K; Al-Shehi, Adel A; Al-Matrushi, Abdulrahman M; Ammara, Ume; Briddon, Rob W

2014-03-01

For last two decades, begomoviruses (family Geminiviridae) have been a major constraint for tomato production in Oman, particularly in the Al-Batinah region, the major agricultural area of Oman. Farms in the Al-Batinah region were surveyed during January-March and November-December in 2012 and January-February in 2013. Leaf samples of tomato plants showing typical leaf curl disease symptoms were collected and analyzed for begomoviruses. Out of fifteen begomovirus clones sequenced, seven were shown to be tomato yellow leaf curl virus strain Oman (TYLCV-OM); three, chili leaf curl virus strain Oman (ChLCV-OM); and one, tomato leaf curl Oman virus (ToLCOMV) - viruses that have previously been shown to occur in Oman. Four sequences were shown to have relatively low percent identity values to known begomoviruses, with the highest (86 %) to isolates of pepper leaf curl Lahore virus, indicating that these should be included in a new species, for which the name "Tomato leaf curl Al Batinah virus" (ToLCABV) is proposed. Although the betasatellite tomato leaf curl betasatellite (ToLCB; 7 full-length sequences isolated) was identified with some isolates of ChLCV-OM, TYLCV-OM and ToLCOMV, it was not identified in association with any of the ToLCABV isolates. Analysis of the sequences of the TYLCV-OM and ToLCOMV isolates characterized here did not show them to differ significantly from previously characterized isolates of these viruses. The three isolates of ChLCV-OM characterized were shown to have a recombination pattern distinct from earlier characterized isolates. ToLCABV was shown to have resulted from recombination between ChLCV-OM and ToLCOMV. A clone of ToLCABV was infectious by Agrobacterium-mediated inoculation to Nicotiana benthamiana and tomato, inducing symptoms typical of those seen in tomato in the field. Additionally, ToLCABV was shown to be able to interact in planta with ToLCB, resulting in a change in symptom phenotype, although the betasatellite did not

Molecular characterization and prevalence of two capulaviruses: Alfalfa leaf curl virus from France and Euphorbia caput-medusae latent virus from South Africa.

Science.gov (United States)

Bernardo, Pauline; Muhire, Brejnev; François, Sarah; Deshoux, Maëlle; Hartnady, Penelope; Farkas, Kata; Kraberger, Simona; Filloux, Denis; Fernandez, Emmanuel; Galzi, Serge; Ferdinand, Romain; Granier, Martine; Marais, Armelle; Monge Blasco, Pablo; Candresse, Thierry; Escriu, Fernando; Varsani, Arvind; Harkins, Gordon W; Martin, Darren P; Roumagnac, Philippe

2016-06-01

Little is known about the prevalence, diversity, evolutionary processes, genomic structures and population dynamics of viruses in the divergent geminivirus lineage known as the capulaviruses. We determined and analyzed full genome sequences of 13 Euphorbia caput-medusae latent virus (EcmLV) and 26 Alfalfa leaf curl virus (ALCV) isolates, and partial genome sequences of 23 EcmLV and 37 ALCV isolates. While EcmLV was asymptomatic in uncultivated southern African Euphorbia caput-medusae, severe alfalfa disease symptoms were associated with ALCV in southern France. The prevalence of both viruses exceeded 10% in their respective hosts. Besides using patterns of detectable negative selection to identify ORFs that are probably functionally expressed, we show that ALCV and EcmLV both display evidence of inter-species recombination and biologically functional genomic secondary structures. Finally, we show that whereas the EcmLV populations likely experience restricted geographical dispersion, ALCV is probably freely moving across the French Mediterranean region. Copyright © 2016 Elsevier Inc. All rights reserved.

Within-host dynamics of the emergence of Tomato yellow leaf curl virus recombinants.

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Cica Urbino

Full Text Available Tomato yellow leaf curl virus (TYLCV is a highly damaging begomovirus native to the Middle East. TYLCV has recently spread worldwide, recombining with other begomoviruses. Recent analysis of mixed infections between TYLCV and Tomato leaf curl Comoros begomovirus (ToLCKMV has shown that, although natural selection preserves certain co-evolved intra-genomic interactions, numerous and diverse recombinants are produced at 120 days post-inoculation (dpi, and recombinant populations from different tomato plants are very divergent. Here, we investigate the population dynamics that lead to such patterns in tomato plants co-infected with TYLCV and ToLCKMV either by agro-inoculation or using the natural whitefly vector Bemisia tabaci. We monitored the frequency of parental and recombinant genotypes independently in 35 plants between 18 and 330 dpi and identified 177 recombinants isolated at different times. Recombinants were detected from 18 dpi and their frequency increased over time to reach about 50% at 150 dpi regardless of the inoculation method. The distribution of breakpoints detected on 96 fully sequenced recombinants was consistent with a continuous generation of new recombinants as well as random and deterministic effects in their maintenance. A severe population bottleneck of around 10 genomes was estimated during early systemic infection-a phenomenon that could account partially for the heterogeneity in recombinant patterns observed among plants. The detection of the same recombinant genome in six of the thirteen plants analysed beyond 30 dpi supported the influence of selection on observed recombination patterns. Moreover, a highly virulent recombinant genotype dominating virus populations within one plant has, apparently, the potential to be maintained in the natural population according to its infectivity, within-host accumulation, and transmission efficiency - all of which were similar or intermediate to those of the parent genotypes. Our

Detection and molecular characterization of tomato yellow leaf curl virus naturally infecting Lycopersicon esculentum in Egypt.

Science.gov (United States)

Rabie, M; Ratti, C; Abdel Aleem, E; Fattouh, F

Tomato yellow leaf curl virus (TYLCV) infections of tomato crops in Egypt were widely spread in 2014. Infected symptomatic tomato plants from different governorates were sampled. TYLCV strains Israel and Mild (TYLCV-IL, TYLCV-Mild) were identified by multiplex and real-time PCR. In addition, nucleotide sequence analysis of the V1 and V2 protein genes, revealed ten TYLCV Egyptian isolates (TYLCV from TY1 to 10). Phylogenetic analysis showed their high degree of relatedness with TYLCV-IL Jordan isolate (98%). Here we have showed the complete nucleotide sequence of the TYLCV Egyptian isolate TY10, sampled from El Beheira. A high degree of similarity to other previously reported Egyptian isolates and isolates from Jordan and Japan reflect the importance of phylogenetic analysis in monitoring virus genetic diversity and possibilities for divergence of more virulent strains or genotypes.

Properties of a virus causing mosaic and leaf curl disease of Celosia argentea L. in Nigeria.

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Owolabi, T A; Taiwo, M A; Thottappilly, G A; Shoyinka, S A; Proll, E; Rabenstein, F

1998-06-01

A sap transmissible virus, causing mosaic and leaf curl disease of Celosia argentea, was isolated at vegetable farms in Amuwo Odofin, Tejuoso, and Abule Ado, Lagos, Nigeria. The virus had a restricted host range confined to a few species of the Amaranthaceae, Chenopodiaceae and Solanaceae families. It failed to infect several other species of the Aizoaceae, Brassicaceae, Cucurbitaceae, Fabaceae, Lamiaceae, Malvaceae, Poaceae and Tiliaceae families. The virus was transmitted in a non-persistent manner by Aphis spiraecola and Toxoptera citricidus but not by eight other aphid species tested. There was no evidence of transmission by seeds of C. argentae varieties. The viral coat protein had a relative molecular mass (M(r)) of about 30.2 K. Electron microscopy of purified virus preparations revealed flexuous rod shaped particles of about 750 nm in length. Serological studies were performed using the enzyme-linked immunosorbent assay (ELISA), immunosorbent electron microscopy (ISEM) and Western blot analysis. The virus reacted positively with an universal potyvirus group monoclonal antibody (MoAb) and MoAb P-3-3H8 raised against peanut stripe potyvirus. It also reacted with polyclonal antibodies raised against several potyviruses including asparagus virus-1 (AV-1), turnip mosaic virus (TuMV), maize dwarf mosaic virus (MDMV), watermelon mosaic virus (WMV-2), plum pox virus (PPV), soybean mosaic virus (SoyMV), lettuce mosaic virus (LMV), bean common mosaic virus (BCMV) and beet mosaic virus (BMV) in at least one of the serological assays used. On the basis of host range, mode of transmission, and available literature data, the celosia virus seems to be different from potyviruses previously reported to infect vegetables in Nigeria. The name celosia mosaic virus (CIMV) has been proposed for this virus.

Molecular characterization of two isolates of sweet potato leaf curl ...

African Journals Online (AJOL)

Jane

2011-08-17

Aug 17, 2011 ... related to that of sweet potato leaf curl virus (SPLCV) from United States with nucleotide sequence identity of ... species including Ipomoea indica, are grown orna- mentally all .... and AC4 were closely related to that of SPLCV-.

A simple, rapid and inexpensive method for localization of Tomato yellow leaf curl virus and Potato leafroll virus in plant and insect vectors.

Science.gov (United States)

Ghanim, Murad; Brumin, Marina; Popovski, Smadar

2009-08-01

A simple, rapid, inexpensive method for the localization of virus transcripts in plant and insect vector tissues is reported here. The method based on fluorescent in situ hybridization using short DNA oligonucleotides complementary to an RNA segment representing a virus transcript in the infected plant or insect vector. The DNA probe harbors a fluorescent molecule at its 5' or 3' ends. The protocol: simple fixation, hybridization, minimal washing and confocal microscopy, provides a highly specific signal. The reliability of the protocol was tested by localizing two phloem-limited plant virus transcripts in infected plants and insect tissues: Tomato yellow leaf curl virus (TYLCV) (Begomovirus: Geminiviridae), exclusively transmitted by the whitefly Bemisia tabaci (Gennadius) in a circulative non-propagative manner, and Potato leafroll virus (Polerovirus: Luteoviridae), similarly transmitted by the aphid Myzus persicae (Sulzer). Transcripts for both viruses were localized specifically to the phloem sieve elements of infected plants, while negative controls showed no signal. TYLCV transcripts were also localized to the digestive tract of B. tabaci, confirming TYLCV route of transmission. Compared to previous methods for localizing virus transcripts in plant and insect tissues that include complex steps for in-vitro probe preparation or antibody raising, tissue fixation, block preparation, sectioning and hybridization, the method described below provides very reliable, convincing, background-free results with much less time, effort and cost.

Identification of a disease complex involving a novel monopartite begomovirus with beta- and alphasatellites associated with okra leaf curl disease in Oman.

Science.gov (United States)

Akhtar, Sohail; Khan, Akhtar J; Singh, Achuit S; Briddon, Rob W

2014-05-01

Okra leaf curl disease (OLCD) is an important viral disease of okra in tropical and subtropical areas. The disease is caused by begomovirus-satellite complexes. A begomovirus and associated betasatellite and alphasatellite were identified in symptomatic okra plants from Barka, in the Al-Batinah region of Oman. Analysis of the begomovirus sequences showed them to represent a new begomovirus most closely related to cotton leaf curl Gezira virus (CLCuGeV), a begomovirus of African origin. The sequences showed less than 85 % nucleotide sequence identity to CLCuGeV isolates. The name okra leaf curl Oman virus (OLCOMV) is proposed for the new virus. Further analysis revealed that the OLCOMV is a recombinant begomovirus that evolved by the recombination of CLCuGeV isolates with tomato yellow leaf curl virus-Oman (TYLCV-OM). An alpha- and a betasatellite were also identified from the same plant sample, which were also unique when compared to sequences available in the databases. However, although the betasatellite appeared to be of African origin, the alphasatellite was most closely related to alphasatellites originating from South Asia. This is the first report of a begomovirus-satellite complex infecting okra in Oman.

Genetic diversity in upland cotton for cotton leaf curl virus disease, earliness and fiber quality

International Nuclear Information System (INIS)

Saeed, F.; Farooq, J.; Mahmood, A.; Hussain, T.

2014-01-01

In Pakistan during last two decades the major factor limiting cotton production is cotton leaf curl virus disease (CLCuD). For estimation of genetic diversity regarding CLCuD tolerance, fiber quality and some yield contributing traits, 101 cotton genotypes imported from USA were evaluated. Different statistical procedures like cluster, principle components (PC) and correlation analysis were employed to identify the suitable genotypes that can be further exploited in breeding programme. Significant associations were found between yield contributing trait, boll weight and fiber related trait, staple length. Earliness related traits, like days taken to 1 square and days taken to 1 flower had positive correlation with each other and both these traits also showed their positive association with ginning out turn. The negative significant correlation of CLCuD was obtained with monopodial branches, sympodial branches and plant height. Principal component (PC) analysis showed first five PCs having eigen value >1 explaining 67.8% of the total variation with days to st 1 square and flowering along with plant height and sympodia plant which were being the most important characters in PC1. Cluster analysis classified 101 accessions into five divergent groups. The genotypes in st cluster 1 only showed reasonable values for days to 1 square and flower, sympodia per plant, ginning out turn, staple length and fiber fineness and the genotypes in cluster 5 showed promising values for the traits like cotton leaf curl virus, ginning out turn and fiber fineness. The genotypes in cluster 1 and 5 may be combined to obtain desirable traits related to earliness and better disease tolerance. Scatter plot and tree diagrams demonstrated sufficient diversity among the cotton accessions for various traits and some extent of association between various clusters. It is concluded that diversity among the genotypes could be utilized for the development of CLCuD resistant lines with increased seed

Detection and Host Range Study of Virus Associated with Pepper Yellow Leaf Curl Disease

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SRI SULANDARI

2006-03-01

Full Text Available High incidence of Pepper yellow leaf curl virus (PepYLCV was observed in Indonesia since early 2000. Disease incidence in Yogyakarta, Central and West Java reached 100% on Capsicum frutescens, but only 10-35% on C. annuum. As an exception, the disease incidence on C. annuum cv. TM 999 was in the range of 70-100%. The causal agent of the disease, PepYLCV, was detected by polymerase chain reaction. Viral specific DNA fragment of the size ~1600 bp and ~550 bp was amplified from infected plants using two pairs of geminivirus universal primers pAL1v1978/pAL1c715, and pAv494/pAc1048, respectively. The PepYLCV has an intermediate host range including plants belonging to the family of Solanaceae, Leguminosae, and Compositae. The species belonging to the families of Cucurbitaceae, Malvaceae, Chenopodiaceae, and Amaranthaceae were resistant to the virus. Physalis floridana, is very prospective as a propagation host for the geminivirus infecting pepper. Nicotiana spp., cucumber, watermelon, cotton, and Sida sp. could be used as a differential host. Besides, Capsicum frutescens cv. Cakra, tomato, N. benthamiana, N. glutinosa, and Ageratum conyzoides could be used as indicator plants for the geminivirus infecting pepper.

The merging of two dynasties--identification of an African cotton leaf curl disease-associated begomovirus with cotton in Pakistan.

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Muhammad Nouman Tahir

Full Text Available Cotton leaf curl disease (CLCuD is a severe disease of cotton that occurs in Africa and Pakistan/northwestern India. The disease is caused by begomoviruses in association with specific betasatellites that differ between Africa and Asia. During survey of symptomatic cotton in Sindh (southern Pakistan Cotton leaf curl Gezira virus (CLCuGV, the begomovirus associated with CLCuD in Africa, was identified. However, the cognate African betasatellite (Cotton leaf curl Gezira betasatellite was not found. Instead, two Asian betasatellites, the CLCuD-associated Cotton leaf curl Multan betasatellite (CLCuMB and Chilli leaf curl betasatellite (ChLCB were identified. Inoculation of the experimental plant species Nicotiana benthamiana showed that CLCuGV was competent to maintain both CLCuMB and ChLCB. Interestingly, the enations typical of CLCuD were only induced by CLCuGV in the presence of CLCuMB. Also in infections involving both CLCuMB and ChLCB the enations typical of CLCuMB were less evident. This is the first time an African begomovirus has been identified on the Indian sub-continent, highlight the growing threat of begomoviruses and particularly the threat of CLCuD causing viruses to cotton cultivation in the rest of the world.

Ribbon curling

Science.gov (United States)

Juel, Anne; Prior, Chris; Moussou, Julien; Chakrabarti, Buddhapriya; Jensen, Oliver

The procedure of curling a ribbon by running it over a sharp blade is commonly used when wrapping presents. Despite its ubiquity, a quantitative explanation of this everyday phenomenon is still lacking. We address this using experiment and theory, examining the dependence of ribbon curvature on blade curvature, the longitudinal load imposed on the ribbon and the speed of pulling. Experiments in which a ribbon is drawn steadily over a blade under a fixed load show that the ribbon curvature is generated over a restricted range of loads, the curvature/load relationship can be non-monotonic, and faster pulling (under a constant imposed load) results in less tightly curled ribbons. We develop a theoretical model that captures these features, building on the concept that the ribbon under the imposed deformation undergoes differential plastic stretching across its thickness, resulting in a permanently curved shape. The model identifies factors that optimize curling and clarifies the physical mechanisms underlying the ribbon's nonlinear response to an apparently simple deformation.

Combining ability estimates for earliness in cotton leaf curl virus resistant inbred parents

International Nuclear Information System (INIS)

Baloch, M.J.; Baloch, Q.B.

2005-01-01

Four female cotton leaf curl virus-resistant resistant (cclv) parents consisting of advance strains and commercial varieties (VH-137, FH-901, CRIS-467 and Cyto-51) and four male parents, all clcv resistant Punjab varieties (FH-945, CIM-707, CIM-473 and FH-1000) were mated in a cross classification Design-II fashion. The results show that genetic variances due to additive genes were higher than the dominant variances, yet both types of variances were substantial, implying that significant improvement could reliably be made from segregating populations. The general combining ability (gca) estimates by and large suggested that for improvement in the appearance of first white flower and 1st sympodial branch node number, parents FH-945 and VH-137 whereas for 1st effective boll setting, parents FH-1000 and FH-901 and for percent of open bolls at 120 days after planting, parents CIM-707 and CRIS-467 may be given preference. However, for hybrid cotton development regarding earliness, hybrids CRIS-467 x CIM-707, VH-137 x FH-945 and Cyto-51 x FH-1000 may be chosen. (author)

Comparative Analyses of Tomato yellow leaf curl virus C4 Protein-Interacting Host Proteins in Healthy and Infected Tomato Tissues

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Namgyu Kim

2016-10-01

Full Text Available Tomato yellow leaf curl virus (TYLCV, a member of the genus Begomovirus, is one of the most important viruses of cultivated tomatoes worldwide, mainly causing yellowing and curling of leaves with stunting in plants. TYLCV causes severe problems in sub-tropical and tropical countries, as well as in Korea. However, the mechanism of TYLCV infection remains unclear, although the function of each viral component has been identified. TYLCV C4 codes for a small protein involved in various cellular functions, including symptom determination, gene silencing, viral movement, and induction of the plant defense response. In this study, through yeast-two hybrid screenings, we identified TYLCV C4-interacting host proteins from both healthy and symptom-exhibiting tomato tissues, to determine the role of TYLCV C4 proteins in the infection processes. Comparative analyses of 28 proteins from healthy tissues and 36 from infected tissues showing interactions with TYLCV C4 indicated that TYLCV C4 mainly interacts with host proteins involved in translation, ubiquitination, and plant defense, and most interacting proteins differed between the two tissues but belong to similar molecular functional categories. Four proteins—two ribosomal proteins, S-adenosyl-L-homocysteine hydrolase, and 14-3-3 family protein—were detected in both tissues. Furthermore, the identified proteins in symptom-exhibiting tissues showed greater involvement in plant defenses. Some are key regulators, such as receptor-like kinases and pathogenesis-related proteins, of plant defenses. Thus, TYLCV C4 may contribute to the suppression of host defense during TYLCV infection and be involved in ubiquitination for viral infection.

Characterization of alphasatellites associated with monopartite begomovirus/betasatellite complexes in Yunnan, China

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Gong Huanran

2010-08-01

Full Text Available Abstract Background Alphasatellites are single-stranded molecules that are associated with monopartite begomovirus/betasatellite complexes. Results Alphasatellites were identified in begomovirus-infected plant samples in Yunnan, China. All samples that contained alphasatellites also contained betasatellites, but only some samples that contained betasatellites contained alphasatellites. Thirty-three alphasatellites were sequenced, and they ranged from 1360 to 1376 nucleotides. All alphasatellites contain 3 conserved features: a single open reading frame (Rep, a conserved hairpin structure, and an adenine-rich (A-rich region. On the basis of the phylogenetic tree of the complete nucleotide sequences, the alphasatellites were divided into 3 types with one exception. Type 1 was associated with Tomato yellow leaf curl China virus (TYLCCNV/Tomato yellow leaf curl China betasatellite (TYLCCNB complex. Type 2 was associated with Tobacco curly shoot virus (TbCSV/Tobacco curly shoot betasatellite (TbCSB complex. Type 3 was associated with TbCSV/Ageratum yellow vein betasatellite (AYVB complex. Within each type, nucleotide sequence identity ranged from 83.4 to 99.7%, while 63.4-81.3% identity was found between types. Mixed infections of alphasatellites associated with begomovirus/betasatellite complexes were documented. Conclusions Our results validate that alphasatellites are only associated with begomovirus/betasatellite complexes. Thirty-three sequenced alphasatellites isolated from Yunnan Province, China were divided into 3 types--each associated with a specific begomovirus/betasatellite complex. Mix-infections of alphasatellite molecules may not be unusual.

Molecular evidence for the occurrence of tomato leaf curl New Delhi virus on chayote (Sechium edule) in southern India.

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Nagendran, K; Mohankumar, S; Mohammed Faisal, P; Bagewadi, B; Karthikeyan, G

2017-12-01

During 2012-2014, mosaic disease on chayote in the farmers field of Kodaikanal region (high altitude zone) of Tamil Nadu was observed. The disease was characterized with severe mosaic, cupping and enation on leaves with reduced fruit size. Disease was found to causes an yield loss of more than 60% with the maximum disease incidence of 100% for the past 5 years consecutively. Preliminary serological and molecular screening indicated the association of begomovirus with the disease. Complete nucleotide sequence and phylogenetic analysis of DNA A revealed the identity of the virus as tomato leaf curl New Delhi virus (ToLCNDV). In recombination analysis study, the major parent was identified as ToLCNDV from Pakistan infecting tomato. Thus the present finding confirms expansion of new geographical region and host for ToLCNDV causing mosaic disease on chayote from Tamil Nadu. To our knowledge this is the first confirmed report for the occurrence of ToLCNDV on chayote in southern India.

Curling for Confidence: Psychophysical Benefits of Curling for Older Adults.

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Stone, Rachael C; Rakhamilova, Zina; Gage, William H; Baker, Joseph

2018-04-01

While physical activity is increasingly promoted for older adults, there is a paucity of sport promotion, which has distinct benefits from exercise and remains stereotypically associated with younger age. Curling is a moderately intense and safe sport that continues to gain popularity; however, no research has investigated psychophysical benefits of curling for older adults. The present study compares high-experience (20+ years; n = 63) and low-experience (<20 years; n = 53) curlers (aged 60+ years) with older adult noncurlers (n = 44) on measures of daily functionality, balance confidence, and perceptions of the aging process. While no significant differences were found between high- and low-experience curlers, any level of experience reported significantly better functionality, physical confidence, and aging attitudes compared to noncurlers (p ≤ .05). Although further research is necessary, the results suggest that any level of curling experience can enhance older adult psychophysical well-being, and warrants consideration for physical activity promotion and falls prevention programs.

Aphid transmission of Lettuce necrotic leaf curl virus, a member of a tentative new subgroup within the genus Torradovirus.

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Verbeek, Martin; Dullemans, Annette M; van der Vlugt, René A A

2017-09-15

Lettuce necrotic leaf curl virus (LNLCV) was described as the first non-tomato-infecting member of the genus Torradovirus. Until today, the virus was found only in The Netherlands in two different areas in open field crops of lettuce. In 2015, LNLCV was accepted by the ICTV as a new member of the genus Torradovirus. The tomato-infecting (TI) torradoviruses Tomato torrado virus (ToTV), Tomato marchitez virus (ToMarV) and Tomato chocolàte virus (ToChV) are transmitted by at least three whitefly species in a semi-persistent and stylet-borne manner. As LNLCV was transmitted in open fields in The Netherlands, where whiteflies are present only in low incidence, transmission studies were set up to identify the natural vector of LNLCV. Whitefly species which survive Dutch open field conditions during summer, as well as lettuce colonizing aphid species, were tested for their ability to transmit LNLCV. Lengths of acquisition and inoculation periods were chosen in accordance with the conditions for TI torradoviruses. Transmission experiments involving whiteflies were never successful. Transmission with aphids was only successful in case of the lettuce-currant aphid, Nasonovia ribisnigri. Localization of LNLCV virions in N. ribisnigri with a nested RT-PCR indicated the stylets as possible retention sites. The willow-carrot aphid Cavariella aegopodii did not transmit LNLCV in our transmission experiment but the virus could be detected in the stylets of this aphid, leaving C. aegopodii as a possible vector for LNLCV. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Diversity in Betasatellites Associated with Cotton Leaf Curl Disease During Source-To-Sink Movement Through a Resistant Host

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Iftikhar Ali Khan

2016-02-01

Full Text Available Cotton leaf curl is devastating disease of cotton characterized by leaf curling, vein darkening and enations. The disease symptoms are induced by DNA satellite known as Cotton leaf curl Multan betasatellite (CLCuMuB, dominant betasatellite in cotton but another betasatellite known as Chili leaf curl betasatellite (ChLCB is also found associated with the disease. Grafting experiment was performed to determine if host plant resistance is determinant of dominant population of betasatellite in cotton (several distinct strains of CLCuMuB are associated with the disease. Infected scion of Gossypium hirsutum collected from field (the source was grafted on G. arboreum, a diploid cotton species, resistant to the disease. A healthy scion of G. hirsutum (sink was grafted at the top of G. arboreum to determine the movement of virus/betasatellite to upper susceptible scion of G. hirsutum. Symptoms of disease appeared in the upper scion and presence of virus/betasatellite in the upper scion was confirmed via molecular techniques, showing that virus/betasatellite was able to move to upper scion through resistant G. arboreum. However, no symptoms appeared on G. arboreum. Betasatelites were cloned and sequenced from lower scion, upper scion and G. arboreum which show that the lower scion contained both CLCuMuB and ChLCB, however only ChLCB was found in G. arboreum. The upper scion contained CLCuMuB with a deletion of 78 nucleotides (nt in the non-coding region between A-rich sequence and βC1 gene and insertion of 27 nt in the middle of βC1 ORF. This study may help in investigating molecular basis of resistance in G. arboreum.

Deformation behavior of curling strips on tearing tubes

Energy Technology Data Exchange (ETDEWEB)

Choi, Ji Won; Kwon, Tae Soo; Jung, Hyun Seung; Kim, Jin Sung [Dept. of Robotics and Virtual Engineering, Korea University of Science and Technology, Seoul (Korea, Republic of)

2015-10-15

This paper discusses the analysis of the curl deformation behavior when a dynamic force is applied to a tearing tube installed on a flat die to predict the energy absorption capacity and deformation behavior. The deformation of the tips of the curling strips was obtained when the curl tips and tube body are in contact with each other, and a formula describing the energy dissipation rate caused by the deformation of the curl tips is proposed. To improve this formula, we focused on the variation of the curl radius and the reduced thickness of the tube. A formula describing the mean curl radius is proposed and verified using the curl radius measurement data of collision test specimens. These improved formulas are added to the theoretical model previously proposed by Huang et al. and verified from the collision test results of a tearing tube.

Wheat curl mite and dry bulb mite: untangling a taxonomic conundrum through a multidisciplinary approach

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The taxonomy of two economically important eriophyoid species, Aceria tosichella (wheat curl mite, WCM) and A. tulipae (dry bulb mite, DBM), was confounded in the world literature until the late 20th century due to their morphological similarity and ambiguous data from plant-transfer and virus-trans...

Expression of tomato yellow leaf curl virus coat protein using baculovirus expression system and evaluation of its utility as a viral antigen.

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Elgaied, Lamiaa; Salem, Reda; Elmenofy, Wael

2017-08-01

DNA encoding the coat protein (CP) of an Egyptian isolate of tomato yellow leaf curl virus (TYLCV) was inserted into the genome of Autographa californica nucleopolyhedrovirus (AcNPV) under the control of polyhedrin promoter. The generated recombinant baculovirus construct harboring the coat protein gene was characterized using PCR analysis. The recombinant coat protein expressed in infected insect cells was used as a coating antigen in an indirect Enzyme-linked immunosorbent assay (ELISA) and dot blot to test its utility for the detection of antibody generated against TYLCV virus particles. The results of ELISA and dot blot showed that the TYLCV-antibodies reacted positively with extracts of infected cells using the recombinant virus as a coating antigen with strong signals as well as the TYLCV infected tomato and beat plant extracts as positive samples. Scanning electron microscope examination showed that the expressed TYLCV coat protein was self-assembled into virus-like particles (VLPs) similar in size and morphology to TYLCV virus particles. These results concluded that, the expressed coat protein of TYLCV using baculovirus vector system is a reliable candidate for generation of anti-CP antibody for inexpensive detection of TYLCV-infected plants using indirect CP-ELISA or dot blot with high specificity.

Real-time PCR protocols for the quantification of the begomovirus tomato yellow leaf curl Sardinia virus in tomato plants and in its insect vector.

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Noris, Emanuela; Miozzi, Laura

2015-01-01

Tomato yellow leaf curl Sardinia virus (TYLCSV) (Geminiviridae) is an important pathogen, transmitted by the whitefly Bemisia tabaci, that severely affects the tomato production in the Mediterranean basin. Here, we describe real-time PCR protocols suitable for relative and absolute quantification of TYLCSV in tomato plants and in whitefly extracts. Using primers and probe specifically designed for TYLCSV, the protocols for relative quantification allow to compare the amount of TYLCSV present in different plant or whitefly samples, normalized to the amount of DNA present in each sample using endogenous tomato or Bemisia genes as internal references. The absolute quantification protocol allows to calculate the number of genomic units of TYLCSV over the genomic units of the plant host (tomato), with a sensitivity of as few as ten viral genome copies per sample. The described protocols are potentially suitable for several applications, such as plant breeding for resistance, analysis of virus replication, and virus-vector interaction studies.

Isolation and sequence characterization of DNA-A genome of a new begomovirus strain associated with severe leaf curling symptoms of Jatropha curcas L.

KAUST Repository

Chauhan, Sushma

2018-04-22

Begomoviruses belong to the family Geminiviridae are associated with several disease symptoms, such as mosaic and leaf curling in Jatropha curcas. The molecular characterization of these viral strains will help in developing management strategies to control the disease. In this study, J. curcas that was infected with begomovirus and showed acute leaf curling symptoms were identified. DNA-A segment from pathogenic viral strain was isolated and sequenced. The sequenced genome was assembled and characterized in detail. The full-length DNA-A sequence was covered by primer walking. The genome sequence showed the general organization of DNA-A from begomovirus by the distribution of ORFs in both viral and anti-viral strands. The genome size ranged from 2844 bp–2852 bp. Three strains with minor nucleotide variations were identified, and a phylogenetic analysis was performed by comparing the DNA-A segments from other reported begomovirus isolates. The maximum sequence similarity was observed with Euphorbia yellow mosaic virus (FN435995). In the phylogenetic tree, no clustering was observed with previously reported begomovirus strains isolated from J. curcas host. The strains isolated in this study belong to new begomoviral strain that elicits symptoms of leaf curling in J. curcas. The results indicate that the probable origin of the strains is from Jatropha mosaic virus infecting J. gassypifolia. The strains isolated in this study are referred as Jatropha curcas leaf curl India virus (JCLCIV) based on the major symptoms exhibited by host J. curcas.

Implication of the Whitefly Bemisia tabaci Cyclophilin B Protein in the Transmission of Tomato yellow leaf curl virus.

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Kanakala, Surapathrudu; Ghanim, Murad

2016-01-01

Tomato yellow leaf curl virus (TYLCV) is a single-stranded (ssDNA) begomoviruses that causes severe damage to tomato and several other crops worldwide. TYLCV is exclusively transmitted by the sweetpotato whitefly, Bemisia tabaci in a persistent circulative and propagative manner. Previous studies have shown that the transmission, retention, and circulation of TYLCV in its vector involves interaction with insect and endosymbiont proteins, which aid in the transmission of the virus, or have a protective role in response to the presence of the virus in the insect body. However, only a low number of such proteins have been identified. Here, the role of B. tabaci Cyclophilin B (CypB) in the transmission of TYLCV protein was investigated. Cyclophilins are a large family of cellular prolyl isomerases that have many molecular roles including facilitating protein-protein interactions in the cell. One cyclophilin protein has been implicated in aphid-luteovirus interactions. We demonstrate that the expression of CypB from B. tabaci is altered upon TYLCV acquisition and retention. Further experiments used immunocapture-PCR and co-immunolocalization and demonstrated a specific interaction and colocalization between CypB and TYLCV in the the midgut, eggs, and salivary glands. Membrane feeding of anti-CypB antibodies and TYLCV-infected plants showed a decrease in TYLCV transmission, suggesting a critical role that CypB plays in TYLCV transmission. Further experiments, which used membrane feeding with the CypB inhibitor Cyclosporin A showed decrease in CypB-TYLCV colocalization in the midgut and virus transmission. Altogether, our results indicate that CypB plays an important role in TYLCV transmission by B. tabaci .

Implication of the whitefly Bemisia tabaci Cyclophilin B protein in the transmission of Tomato yellow leaf curl virus

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Surapathrudu Kanakala

2016-11-01

Full Text Available Tomato yellow leaf curl virus (TYLCV is a single-stranded (ssDNA begomoviruses that causes severe damage to tomato and several other crops worldwide. TYLCV is exclusively transmitted by the sweetpotato whitefly, Bemisia tabaci in a persistent circulative and propagative manner. Previous studies have shown that the transmission, retention and circulation of TYLCV in its vector involves interaction with insect and endosymbiont proteins, which aid in the transmission of the virus, or have a protective role in response to the presence of the virus in the insect body. However, only a low number of such proteins have been identified. Here, the role of B. tabaci Cyclophilin B (CypB in the transmission of TYLCV protein was investigated. Cyclophilins (Cyps are a large family of cellular prolyl isomerases that have many molecular roles including facilitating protein-protein interactions in the cell. One cyclophilin protein has been implicated in aphid-luteovirus interactions. We demonstrate that the expression of CypB from B. tabaci is altered upon TYLCV acquisition and retention. Further experiments used immunocapture-PCR and co-immunolocalization and demonstrated a specific interaction and colocalization between CypB and TYLCV in the the midgut, eggs and salivary glands. Membrane feeding of anti-CypB antibodies and TYLCV infected plants showed a decrease in TYLCV transmission, suggesting a critical role that CypB plays in TYLCV transmission. Further experiments, which used membrane feeding with the CypB inhibitor Cyclosporin A (CsA showed decrease in CypB-TYLCV colocalization in the midgut and virus transmission. Altogether, our results indicate that CypB plays an important role in TYLCV transmission by B. tabaci.

Isolation and sequence characterization of DNA-A genome of a new begomovirus strain associated with severe leaf curling symptoms of Jatropha curcas L.

Science.gov (United States)

Chauhan, Sushma; Rahman, Hifzur; Mastan, Shaik G; Pamidimarri, D V N Sudheer; Reddy, Muppala P

2018-07-20

Begomoviruses belong to the family Geminiviridae are associated with several disease symptoms, such as mosaic and leaf curling in Jatropha curcas. The molecular characterization of these viral strains will help in developing management strategies to control the disease. In this study, J. curcas that was infected with begomovirus and showed acute leaf curling symptoms were identified. DNA-A segment from pathogenic viral strain was isolated and sequenced. The sequenced genome was assembled and characterized in detail. The full-length DNA-A sequence was covered by primer walking. The genome sequence showed the general organization of DNA-A from begomovirus by the distribution of ORFs in both viral and anti-viral strands. The genome size ranged from 2844 bp-2852 bp. Three strains with minor nucleotide variations were identified, and a phylogenetic analysis was performed by comparing the DNA-A segments from other reported begomovirus isolates. The maximum sequence similarity was observed with Euphorbia yellow mosaic virus (FN435995). In the phylogenetic tree, no clustering was observed with previously reported begomovirus strains isolated from J. curcas host. The strains isolated in this study belong to new begomoviral strain that elicits symptoms of leaf curling in J. curcas. The results indicate that the probable origin of the strains is from Jatropha mosaic virus infecting J. gassypifolia. The strains isolated in this study are referred as Jatropha curcas leaf curl India virus (JCLCIV) based on the major symptoms exhibited by host J. curcas. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparative transcriptome profiling of a resistant vs. susceptible tomato (Solanum lycopersicum cultivar in response to infection by tomato yellow leaf curl virus.

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Tianzi Chen

Full Text Available Tomato yellow leaf curl virus (TYLCV threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. The current understanding of the host plant defense response to this virus is very limited. Using whole transcriptome sequencing, we analyzed the differential gene expression in response to TYLCV infection in the TYLCV-resistant tomato breeding line CLN2777A (R and TYLCV-susceptible tomato breeding line TMXA48-4-0 (S. The mixed inoculated samples from 3, 5 and 7 day post inoculation (dpi were compared to non-inoculated samples at 0 dpi. Of the total of 34831 mapped transcripts, 209 and 809 genes were differentially expressed in the R and S tomato line, respectively. The proportion of up-regulated differentially expressed genes (DEGs in the R tomato line (58.37% was higher than that in the S line (9.17%. Gene ontology (GO analyses revealed that similar GO terms existed in both DEGs of R and S lines; however, some sets of defense related genes and their expression levels were not similar between the two tomato lines. Genes encoding for WRKY transcriptional factors, R genes, protein kinases and receptor (-like kinases which were identified as down-regulated DEGs in the S line were up-regulated or not differentially expressed in the R line. The up-regulated DEGs in the R tomato line revealed the defense response of tomato to TYLCV infection was characterized by the induction and regulation of a series of genes involved in cell wall reorganization, transcriptional regulation, defense response, ubiquitination, metabolite synthesis and so on. The present study provides insights into various reactions underlining the successful establishment of resistance to TYLCV in the R tomato line, and helps in the identification of important defense-related genes in tomato for TYLCV disease management.

Computed tomography of ball pythons (Python regius) in curled recumbency.

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Hedley, Joanna; Eatwell, Kevin; Schwarz, Tobias

2014-01-01

Anesthesia and tube restraint methods are often required for computed tomography (CT) of snakes due to their natural tendency to curl up. However, these restraint methods may cause animal stress. The aim of this study was to determine whether the CT appearance of the lungs differs for ball pythons in a curled position vs. tube restraint. Whole body CT was performed on ten clinically healthy ball pythons, first in curled and then in straight positions restrained in a tube. Curved multiplanar reformatted (MPR) lung images from curled position scans were compared with standard MPR lung images from straight position scans. Lung attenuation and thickness were measured at three locations for each scan. Time for positioning and scanning was 12 ± 5 min shorter for curled snakes compared to tube restraint. Lung parenchyma thickness and attenuation declined from cranial to caudal on both straight and curled position images. Mean lung parenchyma thickness was greater in curled images at locations 1 (P = 0.048) and 3 (P = 0.044). Mean lung parenchyma thickness decreased between location 1 and 2 by 86-87% (straight: curled) and between location 1 and 3 by 51-50% (straight: curled). Mean lung attenuation at location 1 was significantly greater on curled position images than tube restraint images (P = 0.043). Findings indicated that CT evaluation of the lungs is feasible for ball pythons positioned in curled recumbency if curved MPR is available. However, lung parenchyma thickness and attenuation in some locations may vary from those acquired using tube restraint. © 2014 American College of Veterinary Radiology.

A Novel H1N2 Influenza Virus Related to the Classical and Human Influenza Viruses from Pigs in Southern China.

Science.gov (United States)

Song, Yafen; Wu, Xiaowei; Wang, Nianchen; Ouyang, Guowen; Qu, Nannan; Cui, Jin; Qi, Yan; Liao, Ming; Jiao, Peirong

2016-01-01

Southern China has long been considered to be an epicenter of pandemic influenza viruses. The special environment, breeding mode, and lifestyle in southern China provides more chances for wild aquatic birds, domestic poultry, pigs, and humans to be in contact. This creates the opportunity for interspecies transmission and generation of new influenza viruses. In this study, we reported a novel reassortant H1N2 influenza virus from pigs in southern China. According to the phylogenetic trees and homology of the nucleotide sequence, the virus was confirmed to be a novel triple-reassortant H1N2 virus containing genes from classical swine (PB2, PB1, HA, NP, and NS genes), triple-reassortant swine (PA and M genes), and recent human (NA gene) lineages. It indicated that the novel reassortment virus among human and swine influenza viruses occurred in pigs in southern China. The isolation of the novel reassortant H1N2 influenza viruses provides further evidence that pigs are "mixing vessels," and swine influenza virus surveillance in southern China will provide important information about genetic evaluation and antigenic variation of swine influenza virus to formulate the prevention and control measures for the viruses.

Implication of the Bacterial Endosymbiont Rickettsia spp. in Interactions of the Whitefly Bemisia tabaci with Tomato yellow leaf curl virus

Science.gov (United States)

Kliot, Adi; Cilia, Michelle; Czosnek, Henryk

2014-01-01

ABSTRACT Numerous animal and plant viruses are transmitted by arthropod vectors in a persistent, circulative manner. Tomato yellow leaf curl virus (TYLCV) is transmitted by the sweet potato whitefly Bemisia tabaci. We report here that infection with Rickettsia spp., a facultative endosymbiont of whiteflies, altered TYLCV-B. tabaci interactions. A B. tabaci strain infected with Rickettsia acquired more TYLCV from infected plants, retained the virus longer, and exhibited nearly double the transmission efficiency compared to an uninfected B. tabaci strain with the same genetic background. Temporal and spatial antagonistic relationships were discovered between Rickettsia and TYLCV within the whitefly. In different time course experiments, the levels of virus and Rickettsia within the insect were inversely correlated. Fluorescence in situ hybridization analysis of Rickettsia-infected midguts provided evidence for niche exclusion between Rickettsia and TYLCV. In particular, high levels of the bacterium in the midgut resulted in higher virus concentrations in the filter chamber, a favored site for virus translocation along the transmission pathway, whereas low levels of Rickettsia in the midgut resulted in an even distribution of the virus. Taken together, these results indicate that Rickettsia, by infecting the midgut, increases TYLCV transmission efficacy, adding further insights into the complex association between persistent plant viruses, their insect vectors, and microorganism tenants that reside within these insects. IMPORTANCE Interest in bacterial endosymbionts in arthropods and many aspects of their host biology in agricultural and human health systems has been increasing. A recent and relevant studied example is the influence of Wolbachia on dengue virus transmission by mosquitoes. In parallel with our recently studied whitefly-Rickettsia-TYLCV system, other studies have shown that dengue virus levels in the mosquito vector are inversely correlated with

The sports science of curling: a practical review.

Science.gov (United States)

Bradley, John L

2009-01-01

Curling is a sport played on ice in which two teams each deliver 8 granite stones towards a target, or 'house'. It is the only sport in which the trajectory of the projectile can be influenced after it has been released by the athlete. This is achieved by sweeping the ice in front of the stone to change the stone-ice friction and thereby enable to stone to travel further, curl more or stay straight. Hard sweeping is physically demanding. Different techniques of sweeping can also have different effects on the stone. This paper will review the current research behind sweeping a curling stone, outline the physiological demands of sweeping, the associated performance effects and suggest potential strategies of sweeping that can be used by both coaches and curling teams. Key pointsSweeping a curling stone can be highly physically demanding.Effective sweeping requires a combination of downward force and brush head speed, determined by the stone velocity.Sweeping on the left or right of a stone can help the stone to remain straight or curl more depending on the rotation of the stone.This can lead to the development of sweeping and playing tactics and contribute to team selection.

Cotton Leaf Curl Multan Betasatellite DNA as a Tool to Deliver and Express the Human B-Cell Lymphoma 2 (Bcl-2) Gene in Plants.

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Kharazmi, Sara; Ataie Kachoie, Elham; Behjatnia, Seyed Ali Akbar

2016-05-01

The betasatellite DNA associated with Cotton leaf curl Multan virus (CLCuMB) contains a single complementary-sense ORF, βC1, which is a pathogenicity determinant. CLCuMB was able to replicate in plants in the presence of diverse helper geminiviruses, including Tomato leaf curl virus-Australia (TLCV-Au), Iranian isolate of Tomato yellow leaf curl virus (TYLCV-[Ab]), and Beet curly top virus (BCTV-Svr), and can be used as a plant gene delivery vector. To test the hypothesis that CLCuMB has the potential to act as an animal gene delivery vector, a specific insertion construct was produced by the introduction of a human B-cell lymphoma 2 (Bcl-2) cDNA into a mutant DNA of CLCuMB in which the βC1 was deleted (β∆C1). The recombinant βΔC1-Bcl-2 construct was successfully replicated in tomato and tobacco plants in the presence of TLCV-Au, BCTV-Svr and TYLCV-[Ab]. Real-time PCR and Western blot analyses of plants containing the replicative forms of recombinant βΔC1-Bcl-2 DNA showed that Bcl-2 gene was expressed in an acceptable level in these plants, indicating that β∆C1 can be used as a tool to deliver and express animal genes in plants. This CLCuMB-based system, having its own promoter activity, offers the possibility of production of animal recombinant proteins in plants.

Functional characterization of a strong bi-directional constitutive plant promoter isolated from cotton leaf curl Burewala virus.

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Zainul A Khan

Full Text Available Cotton leaf curl Burewala virus (CLCuBuV, belonging to the genus Begomovirus, possesses single-stranded monopartite DNA genome. The bidirectional promoters representing Rep and coat protein (CP genes of CLCuBuV were characterized and their efficacy was assayed. Rep and CP promoters of CLCuBuV and 35S promoter of Cauliflower mosaic virus (CaMV were fused with β-glucuronidase (GUS and green fluorescent protein (GFP reporter genes. GUS activity in individual plant cells driven by Rep, CP and 35S promoters was estimated using real-time PCR and fluorometric GUS assay. Histochemical staining of GUS in transformed tobacco (Nicotiana tabacum cv. Xanthi leaves showed highest expression driven by Rep promoter followed by 35S promoter and CP promoter. The expression level of GUS driven by Rep promoter in transformed tobacco plants was shown to be two to four-fold higher than that of 35S promoter, while the expression by CP promoter was slightly lower. Further, the expression of GFP was monitored in agroinfiltrated leaves of N. benthamiana, N. tabacum and cotton (Gossypium hirsutum plants using confocal laser scanning microscopy. Rep promoter showed strong consistent transient expression in tobacco and cotton leaves as compared to 35S promoter. The strong constitutive CLCuBuV Rep promoter developed in this study could be very useful for high level expression of transgenes in a wide variety of plant cells.

[Differences on geographic distribution of rabies virus lineages in China].

Science.gov (United States)

Wang, Q; Li, M L; Chen, Y; Wang, B; Tao, X Y; Zhu, W Y

2018-04-10

Objective: To study the lineages of rabies virus and the epidemic characteristics in different provincial populations of China, to provide information for the development of control and prevention measures in each respective provinces. Methods: Full length N and G genes and full-genome of epidemic strains of rabies virus collected in China were downloaded from GenBank and combined with newly sequenced strains by our lab. Each strain was classified under six lineages of China rabies by constructing phylogenetic trees based on the N or G sequences. Numbers of strains and lineages in each province were counted and compared. Results: Six lineages (China Ⅰ-Ⅵ) were prevalent in China, with 4 found in Yunnan and Hunan. In 6 provinces, including Henan and Fujian, 3 lineages were found. In 8 provinces, including Shanghai and Jiangxi, 2 lineages were found Only 1 lineage, were found in Beijing, Tianjin and other 12 provinces. the China Ⅰ, was the dominant one in 25 provinces. In recent years, China Ⅲ had been found in wild animals and spread over livestock in Inner Mongolia and Xinjiang areas. Qinghai and Tibet had been influenced by China Ⅳ, which also been found in wild animals of Inner Mongolia and Heilongjiang. Conclusion: There had been obvious differences in lineages and strain numbers of rabies virus identified in different provinces in China.

The typical RB76 recombination breakpoint of the invasive recombinant tomato yellow leaf curl virus of Morocco can be generated experimentally but is not positively selected in tomato.

Science.gov (United States)

Belabess, Z; Urbino, C; Granier, M; Tahiri, A; Blenzar, A; Peterschmitt, M

2018-01-02

TYLCV-IS76 is an unusual recombinant between the highly recombinogenic tomato yellow leaf curl virus (TYLCV) and tomato yellow leaf curl Sardinia virus (TYLCSV), two Mediterranean begomoviruses (Geminiviridae). In contrast with the previously reported TYLCV/TYLCSV recombinants, it has a TYLCSV derived fragment of only 76 nucleotides, and has replaced its parental viruses in natural conditions (Morocco, Souss region). The viral population shift coincided with the deployment of the popular Ty-1 resistant tomato cultivars, and according to experimental studies, has been driven by a strong positive selection in such resistant plants. However, although Ty-1 cultivars were extensively used in Mediterranean countries, TYLCV-IS76 was not reported outside Morocco. This, in combination with its unusual recombination pattern suggests that it was generated through a rare and possibly multistep process. The potential generation of a recombination breakpoint (RB) at locus 76 (RB76) was investigated over time in 10 Ty-1 resistant and 10 nearly isogenic susceptible tomato plants co-inoculated with TYLCV and TYLCSV clones. RB76 could not be detected in the recombinant progeny using the standard PCR/sequencing approach that was previously designed to monitor the emergence of TYLCV-IS76 in Morocco. Using a more sensitive PCR test, RB76 was detected in one resistant and five susceptible plants. The results are consistent with a very low intra-plant frequency of RB76 bearing recombinants throughout the test and support the hypothesis of a rare emergence of TYLCV-IS76. More generally, RBs were more scattered in resistant than in susceptible plants and an unusual RB at position 141 (RB141) was positively selected in the resistant cultivar; interestingly, RB141 bearing recombinants were detected in resistant tomato plants from the field. Scenarios of TYLCV-IS76 pre-emergence are proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

Vector-virus mutualism accelerates population increase of an invasive whitefly.

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Min Jiu

2007-01-01

Full Text Available The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. This variation in relationships may affect the process of biological invasion and the displacement of indigenous species by invaders when the invasive and indigenous organisms occur with niche overlap but differ in the interactions. The notorious invasive B biotype of the whitefly complex Bemisia tabaci entered China in the late 1990s and is now the predominant or only biotype in many regions of the country. Tobacco curly shoot virus (TbCSV and Tomato yellow leaf curl China virus (TYLCCNV are two whitefly-transmitted begomoviruses that have become widespread recently in south China. We compared the performance of the invasive B and indigenous ZHJ1 whitefly biotypes on healthy, TbCSV-infected and TYLCCNV-infected tobacco plants. Compared to its performance on healthy plants, the invasive B biotype increased its fecundity and longevity by 12 and 6 fold when feeding on TbCSV-infected plants, and by 18 and 7 fold when feeding on TYLCCNV-infected plants. Population density of the B biotype on TbCSV- and TYLCCNV-infected plants reached 2 and 13 times that on healthy plants respectively in 56 days. In contrast, the indigenous ZHJ1 performed similarly on healthy and virus-infected plants. Virus-infection status of the whiteflies per se of both biotypes showed limited effects on performance of vectors on cotton, a nonhost plant of the viruses. The indirect mutualism between the B biotype whitefly and these viruses via their host plants, and the apparent lack of such mutualism for the indigenous whitefly, may contribute to the ability of the B whitefly biotype to invade, the displacement of indigenous whiteflies, and the disease pandemics of the viruses associated with this vector.

Swept Away: Exploring the Physics of Curling

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Esser, Liza

2011-01-01

Studying the Olympic sport of curling is a fun and engaging way to learn about the concepts of friction, forces, momentum, and Newton's laws. Each winter, the author takes her eighth-grade physical science class on a field trip to experience curling firsthand. This field trip has become a favorite of the eighth graders at Capitol Hill Day School…

Phylogenetic analysis and inflow route of Tomato yellow leaf curl virus (TYLCV) and Bemisia tabaci in Korea.

Science.gov (United States)

Lee, Hyejung; Song, Woogeun; Kwak, Hae-Ryun; Kim, Jae-Deok; Park, Jungan; Auh, Chung-Kyoon; Kim, Dae-Hyun; Lee, Kyeong-Yeoll; Lee, Sukchan; Choi, Hong-Soo

2010-11-01

Tomato yellow leaf curl virus (TYLCV) is a member of the genus Begomovirus of the family Geminiviridae, members of which are characterized by closed circular single-stranded DNA genomes of 2.7-2.8 kb in length, and include viruses transmitted by the Bemisia tabaci whitefly. No reports of TYLCV in Korea are available prior to 2008, after which TYLCV spread rapidly to most regions of the southern Korean peninsula (Gyeongsang-Do, Jeolla-Do and Jeju-Do). Fifty full sequences of TYLCV were analyzed in this study, and the AC1, AV1, IR, and full sequences were analyzed via the muscle program and bayesian analysis. Phylogenetic analysis demonstrated that the Korea TYLCVs were divided into two subgroups. The TYLCV Korea 1 group (Masan) originated from TYLCV Japan (Miyazaki) and the TYLCV Korea 2 group (Jeju/Jeonju) from TYLCV Japan (Tosa/Haruno). A B. tabaci phylogenetic tree was constructed with 16S rRNA and mitochondria cytochrome oxidase I (MtCOI) sequences using the muscle program and MEGA 4.0 in the neighbor-joining algorithm. The sequence data of 16S rRNA revealed that Korea B. tabaci was closely aligned to B. tabaci isolated in Iran and Nigeria. The Q type of B. tabaci, which was originally identified as a viruliferous insect in 2008, was initially isolated in Korea as a non-viruliferous insect in 2005. Therefore, we suggest that two TYLCV Japan isolates were introduced to Korea via different routes, and then transmitted by native B. tabaci.

Discovering Host Genes Involved in the Infection by the Tomato Yellow Leaf Curl Virus Complex and in the Establishment of Resistance to the Virus Using Tobacco Rattle Virus-based Post Transcriptional Gene Silencing

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Rosa Lozano-Durán

2013-03-01

Full Text Available The development of high-throughput technologies allows for evaluating gene expression at the whole-genome level. Together with proteomic and metabolomic studies, these analyses have resulted in the identification of plant genes whose function or expression is altered as a consequence of pathogen attacks. Members of the Tomato yellow leaf curl virus (TYLCV complex are among the most important pathogens impairing production of agricultural crops worldwide. To understand how these geminiviruses subjugate plant defenses, and to devise counter-measures, it is essential to identify the host genes affected by infection and to determine their role in susceptible and resistant plants. We have used a reverse genetics approach based on Tobacco rattle virus-induced gene silencing (TRV-VIGS to uncover genes involved in viral infection of susceptible plants, and to identify genes underlying virus resistance. To identify host genes with a role in geminivirus infection, we have engineered a Nicotiana benthamiana line, coined 2IRGFP, which over-expresses GFP upon virus infection. With this system, we have achieved an accurate description of the dynamics of virus replication in space and time. Upon silencing selected N. benthamiana genes previously shown to be related to host response to geminivirus infection, we have identified eighteen genes involved in a wide array of cellular processes. Plant genes involved in geminivirus resistance were studied by comparing two tomato lines: one resistant (R, the other susceptible (S to the virus. Sixty-nine genes preferentially expressed in R tomatoes were identified by screening cDNA libraries from infected and uninfected R and S genotypes. Out of the 25 genes studied so far, the silencing of five led to the total collapse of resistance, suggesting their involvement in the resistance gene network. This review of our results indicates that TRV-VIGS is an exquisite reverse genetics tool that may provide new insights into the

Performance of cotton leaf curl virus resistant intrahirsutum f/sub 1/ hybrids

International Nuclear Information System (INIS)

Baloch, M.J.

2004-01-01

The first and foremost effort to combat the devastating cotton leaf curl virus (clcv) disease would be to utilize those clcv resistant germplasm in a hybridization programme which can enhance the possibilities of selecting desirable progenies from segregating populations. In this connection, 16 clcv intrahirsutum F1 hybrids were developed and evaluated for their performance. The hybrids, on an average gave an increase of 26.02 % in seed cotton yield; 11.52 % in bolls per plant; 14.23 % in boll weight; 4.28 % in lint; 3.89 % in fibre length and 8.21 % in earliness against the average of parents. However, among the hybrids, the top three scoring for yield were, BH.121 x Cyto.9/91, Cyto.9/91 x CRIS-226 and VH-137 x CRIS-226. The number of bolls per plant was found to be a major contributing factor for increased yield because the hybrids which set higher bolls correspondingly gave higher yields. Boll weight was not regarded as an important attribute to increase yield because hybrids with moderate boll sizes were among the top three high yielders. For lint %, the hybrids CRIS-129 x LRA-5166 and FH-901 x VH-137 were first for fibre length, whereas CRIS-121 x Cyto.51 and BH-124 x CIM-448 were among the top two rankers. Regarding earliness, the hybrids CRIS-121 x Cyto. 51 gave the highest boll opening percent and next in order was the hybrid VH-137 x DNH-49. Our results thus generally suggest that although the best three hybrids were desirable for other traits, the choice of the hybrids may be made on the priority for characters to be bred. (author)

A Novel H1N2 Influenza Virus Related to the Classical and Human Influenza Viruses from Pigs in Southern China

OpenAIRE

Song, Yafen; Wu, Xiaowei; Wang, Nianchen; Ouyang, Guowen; Qu, Nannan; Cui, Jin; Qi, Yan; Liao, Ming; Jiao, Peirong

2016-01-01

Southern China has long been considered to be an epicenter of pandemic influenza viruses. The special environment, breeding mode, and lifestyle in southern China provides more chances for wild aquatic birds, domestic poultry, pigs, and humans to be in contact. This creates the opportunity for interspecies transmission and generation of new influenza viruses. In this study, we reported a novel reassortant H1N2 influenza virus from pigs in southern China. According to the phylogenetic trees and...

Dissemination, divergence and establishment of H7N9 influenza viruses in China.

Science.gov (United States)

Lam, Tommy Tsan-Yuk; Zhou, Boping; Wang, Jia; Chai, Yujuan; Shen, Yongyi; Chen, Xinchun; Ma, Chi; Hong, Wenshan; Chen, Yin; Zhang, Yanjun; Duan, Lian; Chen, Peiwen; Jiang, Junfei; Zhang, Yu; Li, Lifeng; Poon, Leo Lit Man; Webby, Richard J; Smith, David K; Leung, Gabriel M; Peiris, Joseph S M; Holmes, Edward C; Guan, Yi; Zhu, Huachen

2015-06-04

Since 2013 the occurrence of human infections by a novel avian H7N9 influenza virus in China has demonstrated the continuing threat posed by zoonotic pathogens. Although the first outbreak wave that was centred on eastern China was seemingly averted, human infections recurred in October 2013 (refs 3-7). It is unclear how the H7N9 virus re-emerged and how it will develop further; potentially it may become a long-term threat to public health. Here we show that H7N9 viruses have spread from eastern to southern China and become persistent in chickens, which has led to the establishment of multiple regionally distinct lineages with different reassortant genotypes. Repeated introductions of viruses from Zhejiang to other provinces and the presence of H7N9 viruses at live poultry markets have fuelled the recurrence of human infections. This rapid expansion of the geographical distribution and genetic diversity of the H7N9 viruses poses a direct challenge to current disease control systems. Our results also suggest that H7N9 viruses have become enzootic in China and may spread beyond the region, following the pattern previously observed with H5N1 and H9N2 influenza viruses.

Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures

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Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

2016-01-01

Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency. PMID:26792235

The complete genomic sequence of pepper yellow leaf curl virus (PYLCV and its implications for our understanding of evolution dynamics in the genus polerovirus.

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Aviv Dombrovsky

Full Text Available We determined the complete sequence and organization of the genome of a putative member of the genus Polerovirus tentatively named Pepper yellow leaf curl virus (PYLCV. PYLCV has a wider host range than Tobacco vein-distorting virus (TVDV and has a close serological relationship with Cucurbit aphid-borne yellows virus (CABYV (both poleroviruses. The extracted viral RNA was subjected to SOLiD next-generation sequence analysis and used as a template for reverse transcription synthesis, which was followed by PCR amplification. The ssRNA genome of PYLCV includes 6,028 nucleotides encoding six open reading frames (ORFs, which is typical of the genus Polerovirus. Comparisons of the deduced amino acid sequences of the PYLCV ORFs 2-4 and ORF5, indicate that there are high levels of similarity between these sequences to ORFs 2-4 of TVDV (84-93% and to ORF5 of CABYV (87%. Both PYLCV and Pepper vein yellowing virus (PeVYV contain sequences that point to a common ancestral polerovirus. The recombination breakpoint which is located at CABYV ORF3, which encodes the viral coat protein (CP, may explain the CABYV-like sequences found in the genomes of the pepper infecting viruses PYLCV and PeVYV. Two additional regions unique to PYLCV (PY1 and PY2 were identified between nucleotides 4,962 and 5,061 (ORF 5 and between positions 5,866 and 6,028 in the 3' NCR. Sequence analysis of the pepper-infecting PeVYV revealed three unique regions (Pe1-Pe3 with no similarity to other members of the genus Polerovirus. Genomic analyses of PYLCV and PeVYV suggest that the speciation of these viruses occurred through putative recombination event(s between poleroviruses co-infecting a common host(s, resulting in the emergence of PYLCV, a novel pathogen with a wider host range.

The complete genomic sequence of pepper yellow leaf curl virus (PYLCV) and its implications for our understanding of evolution dynamics in the genus polerovirus.

Science.gov (United States)

Dombrovsky, Aviv; Glanz, Eyal; Lachman, Oded; Sela, Noa; Doron-Faigenboim, Adi; Antignus, Yehezkel

2013-01-01

We determined the complete sequence and organization of the genome of a putative member of the genus Polerovirus tentatively named Pepper yellow leaf curl virus (PYLCV). PYLCV has a wider host range than Tobacco vein-distorting virus (TVDV) and has a close serological relationship with Cucurbit aphid-borne yellows virus (CABYV) (both poleroviruses). The extracted viral RNA was subjected to SOLiD next-generation sequence analysis and used as a template for reverse transcription synthesis, which was followed by PCR amplification. The ssRNA genome of PYLCV includes 6,028 nucleotides encoding six open reading frames (ORFs), which is typical of the genus Polerovirus. Comparisons of the deduced amino acid sequences of the PYLCV ORFs 2-4 and ORF5, indicate that there are high levels of similarity between these sequences to ORFs 2-4 of TVDV (84-93%) and to ORF5 of CABYV (87%). Both PYLCV and Pepper vein yellowing virus (PeVYV) contain sequences that point to a common ancestral polerovirus. The recombination breakpoint which is located at CABYV ORF3, which encodes the viral coat protein (CP), may explain the CABYV-like sequences found in the genomes of the pepper infecting viruses PYLCV and PeVYV. Two additional regions unique to PYLCV (PY1 and PY2) were identified between nucleotides 4,962 and 5,061 (ORF 5) and between positions 5,866 and 6,028 in the 3' NCR. Sequence analysis of the pepper-infecting PeVYV revealed three unique regions (Pe1-Pe3) with no similarity to other members of the genus Polerovirus. Genomic analyses of PYLCV and PeVYV suggest that the speciation of these viruses occurred through putative recombination event(s) between poleroviruses co-infecting a common host(s), resulting in the emergence of PYLCV, a novel pathogen with a wider host range.

Curls of My Dreams.

Science.gov (United States)

Greenman, Geri

2001-01-01

Describes an art activity in which students draw ribbons (thin watercolor paper that, when torn, will stand up in a curling fashion). Explains in detail the assignment in which students used pencil rendering or charcoal pencil depending on the type of paper used for the assignment. (CMK)

Virus infection of a weed increases vector attraction to and vector fitness on the weed.

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Chen, Gong; Pan, Huipeng; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Fang, Yong; Shi, Xiaobin; Zhang, Youjun

2013-01-01

Weeds are important in the ecology of field crops, and when crops are harvested, weeds often become the main hosts for plant viruses and their insect vectors. Few studies, however, have examined the relationships between plant viruses, vectors, and weeds. Here, we investigated how infection of the weed Datura stramonium L. by tomato yellow leaf curl virus (TYLCV) affects the host preference and performance of the TYLCV vector, Bemisia tabaci (Gennadius) Q. The results of a choice experiment indicated that B. tabaci Q preferentially settled and oviposited on TYLCV-infected plants rather than on healthy plants. In addition, B. tabaci Q performed better on TYLCV-infected plants than on healthy plants. These results demonstrate that TYLCV is indirectly mutualistic to B. tabaci Q. The mutually beneficial interaction between TYLCV and B. tabaci Q may help explain the concurrent outbreaks of TYLCV and B. tabaci Q in China.

Classical dynamics with curl forces, and motion driven by time-dependent flux

International Nuclear Information System (INIS)

Berry, M V; Shukla, Pragya

2012-01-01

For position-dependent forces whose curl is non-zero (‘curl forces’), there is no associated scalar potential and therefore no obvious Hamiltonian or Lagrangean and, except in special cases, no obvious conserved quantities. Nevertheless, the motion is nondissipative (measure-preserving in position and velocity). In a class of planar motions, some of which are exactly solvable, the curl force is directed azimuthally with a magnitude varying with radius, and the orbits are usually spirals. If the curl is concentrated at the origin (for example, the curl force could be an electric field generated by a changing localized magnetic flux, as in the betatron), a Hamiltonian does exist but violates the rotational symmetry of the force. In this case, reminiscent of the Aharonov–Bohm effect, the spiralling is extraordinarily slow. (paper)

Pre-infestation of Tomato Plants by Aphids Modulates Transmission-Acquisition Relationship among Whiteflies, Tomato Yellow Leaf Curl Virus (TYLCV and Plants

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Xiao L. Tan

2017-09-01

Full Text Available Herbivory defense systems in plants are largely regulated by jasmonate-(JA and salicylate-(SA signaling pathways. Such defense mechanisms may impact insect feeding dynamic, may also affect the transmission-acquisition relationship among virus, plants and vectoring insects. In the context of the tomato – whitefly – Tomato Yellow Leaf Curl Virus (TYLCV biological model, we tested the impact of pre-infesting plants with a non-vector insect (aphid Myzus persicae on feeding dynamics of a vector insect (whitefly Bemisia tabaci as well as virus transmission-acquisition. We showed that an aphid herbivory period of 0–48 h led to a transient systemic increase of virus concentration in the host plant (root, stem, and leaf, with the same pattern observed in whiteflies feeding on aphid-infested plants. We used real-time quantitative PCR to study the expression of key genes of the SA- and JA-signaling pathways, as well as electrical penetration graph (EPG to characterize the impact of aphid pre-infestation on whitefly feeding during TYLCV transmission (whitefly to tomato and acquisition (tomato to whitefly. The impact of the duration of aphid pre-infestation (0, 24, or 48 h on phloem feeding by whitefly (E2 during the transmission phase was similar to that of global whitefly feeding behavior (E1, E2 and probing duration during the acquisition phase. In addition, we observed that a longer phase of aphid pre-infestation prior to virus transmission by whitefly led to the up-regulation and down-regulation of SA- and JA-signaling pathway genes, respectively. These results demonstrated a significant impact of aphid pre-infestation on the tomato – whitefly – TYLCV system. Transmission and acquisition of TYLCV was positively correlated with feeding activity of B. tabaci, and both were mediated by the SA- and JA-pathways. TYLCV concentration during the transmission phases was modulated by up- and down-regulation of SA- and JA-pathways, respectively. The two

Multiple Virus Infections and the Characteristics of Chronic Bee Paralysis Virus in Diseased Honey Bees (Apis Mellifera L. in China

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Wu Yan Y.

2015-12-01

Full Text Available China has the largest number of managed honey bee colonies globally, but there is currently no data on viral infection in diseased A. mellifera L. colonies in China. In particular, there is a lack of data on chronic bee paralysis virus (CBPV in Chinese honey bee colonies. Consequently, the present study investigated the occurrence and frequency of several widespread honey bee viruses in diseased Chinese apiaries, and we used the reverse transcription-polymerase chain reaction (RT-PCR assay. Described was the relationship between the presence of CBPV and diseased colonies (with at least one of the following symptoms: depopulation, paralysis, dark body colorings and hairless, or a mass of dead bees on the ground surrounding the beehives. Phylogenetic analyses of CBPV were employed. The prevalence of multiple infections of honey bee viruses in diseased Chinese apiaries was 100%, and the prevalence of infections with even five and six viruses were higher than expected. The incidence of CBPV in diseased colonies was significantly higher than that in apparently healthy colonies in Chinese A. mellifera aparies, and CBPV isolates from China can be separated into Chinese-Japanese clade 1 and 2. The results indicate that beekeeping in China may be threatened by colony decline due to the high prevalence of multiple viruses with CBPV.

The Curl of a Vector Field: Beyond the Formula

Science.gov (United States)

Burch, Kimberly Jordan; Choi, Youngna

2006-01-01

It has been widely acknowledged that there is some discrepancy in the teaching of vector calculus in mathematics courses and other applied fields. The curl of a vector field is one topic many students can calculate without understanding its significance. In this paper, we explain the origin of the curl after presenting the standard mathematical…

Detection of yellow fever virus genomes from four imported cases in China.

Science.gov (United States)

Cui, Shujuan; Pan, Yang; Lyu, Yanning; Liang, Zhichao; Li, Jie; Sun, Yulan; Dou, Xiangfeng; Tian, Lili; Huo, Da; Chen, Lijuan; Li, Xinyu; Wang, Quanyi

2017-07-01

Yellow fever virus (YFV), as the first proven human-pathogenic virus, is still a major public health problem with a dramatic upsurge in recent years. This is a report on four imported cases of yellow fever virus into China identified by whole genome sequencing. Phylogenetic analysis was performed and the results showed that these four viruses were highly homologous with Angola 71 strains (AY968064). In addition, effective mutations of amino acids were not observed in the E protein domain of four viruses, thus confirming the effectiveness of the YFV-17D vaccine (X03700). Although there is low risk of local transmission in most part of China, the increasing public health risk of YF caused by international exchange should not be ignored. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Suppressors of RNA silencing encoded by tomato leaf curl

Indian Academy of Sciences (India)

Whitefly-transmitted begomoviruses infecting tomato crop code for five different proteins, ORF AC4, ORF AC2 and ORF AV2 in DNA-A component, ORF BV1 in DNA-B ... In the present study suppressor function of ORF C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl ...

Engineering cotton (Gossypium hirsutum L.) for resistance to cotton leaf curl disease using viral truncated AC1 DNA sequences.

Science.gov (United States)

Hashmi, Jamil A; Zafar, Yusuf; Arshad, Muhammad; Mansoor, Shahid; Asad, Shaheen

2011-04-01

Several important biological processes are performed by distinct functional domains found on replication-associated protein (Rep) encoded by AC1 of geminiviruses. Two truncated forms of replicase (tAC1) gene, capable of expressing only the N-terminal 669 bp (5'AC1) and C-terminal 783 bp (3'AC1) nucleotides cloned under transcriptional control of the CaMV35S were introduced into cotton (Gossypium hirsutum L.) using LBA4404 strain of Agrobacterium tumefaciens to make use of an interference strategy for impairing cotton leaf curl virus (CLCuV) infection in transgenic cotton. Compared with nontransformed control, we observed that transgenic cotton plants overexpressing either N-terminal (5'AC1) or C-terminal (3'AC1) sequences confer resistance to CLCuV by inhibiting replication of viral genomic and β satellite DNA components. Molecular analysis by Northern blot hybridization revealed high transgene expression in early and late growth stages associated with inhibition of CLCuV replication. Of the eight T(1) transgenic lines tested, six had delayed and minor symptoms as compared to nontransformed control lines which developed disease symptoms after 2-3 weeks of whitefly-mediated viral delivery. Virus biological assay and growth of T(2) plants proved that transgenic cotton plants overexpressing 5'- and 3'AC1 displayed high resistance level up to 72, 81%, respectively, as compared to non-transformed control plants following inoculation with viruliferous whiteflies giving significantly high cotton seed yield. Progeny analysis of these plants by polymerase chain reaction (PCR), Southern blotting and virus biological assay showed stable transgene, integration, inheritance and cotton leaf curl disease (CLCuD) resistance in two of the eight transgenic lines having single or two transgene insertions. Transgenic cotton expressing partial AC1 gene of CLCuV can be used as virus resistance source in cotton breeding programs aiming to improve virus resistance in cotton crop.

Rabies Virus Transmission in Solid Organ Transplantation, China, 2015-2016.

Science.gov (United States)

Chen, Shuilian; Zhang, Heng; Luo, Meiling; Chen, Jingfang; Yao, Dong; Chen, Faming; Liu, Ruchun; Chen, Tianmu

2017-09-01

We report rabies virus transmission among solid organ transplantation recipients in Changsha, China, in 2016. Two recipients were confirmed to have rabies and died. Our findings suggest that more attention should be paid to the possibility of rabies virus transmission through organ transplantation for clinical and public health reasons.

Molecular characterization and experimental host range of an isolate of Wissadula golden mosaic St. Thomas virus.

Science.gov (United States)

Collins, A M; Mujaddad-ur-Rehman, Malik; Brown, J K; Reddy, C; Wang, A; Fondong, V; Roye, M E

2009-12-01

Partial genome segments of a begomovirus were previously amplified from Wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of St. Thomas, Jamaica and this isolate assigned to a tentative begomovirus species, Wissadula golden mosaic St. Thomas virus. To clone the complete genome of this isolate of Wissadula golden mosaic St. Thomas virus, abutting primers were designed to PCR amplify its full-length DNA-A and DNA-B components. Sequence analysis of the complete begomovirus genome obtained, confirmed that it belongs to a distinct begomovirus species and this isolate was named Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). The genome of WGMSTV-[JM:Alb:05] is organized similar to that of other bipartite Western Hemisphere begomoviruses. Phylogenetic analyses placed the genome components of WGMSTV-[JM:Alb:05] in the Abutilon mosaic virus clade and showed that the DNA-A component is most closely related to four begomovirus species from Cuba, Tobacco leaf curl Cuba virus, Tobacco leaf rugose virus, Tobacco mottle leaf curl virus, and Tomato yellow distortion leaf virus. The putative Rep-binding-site motif in the common region of WGMSTV-[JM:Alb:05] was observed to be identical to that of Chino del tomate virus-Tomato [Mexico:Sinaloa:1983], Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005], and Tomato leaf curl Sinaloa virus-[Nicaragua:Santa Lucia], suggesting that WGMSTV-[JM:Alb:05] is capable of forming viable pseudo-recombinants with these begomoviruses, but not with other members of the Abutilon mosaic virus clade. Biolistic inoculation of test plant species with partial dimers of the WGMSTV-[JM:Alb:05] DNA-A and DNA-B components showed that the virus was infectious to Nicotiana benthamiana and W. amplissima and the cultivated species Phaseolus vulgaris (kidney bean) and Lycopersicon esculentum (tomato). Infected W. amplissima plants developed symptoms similar to symptoms observed under field

Molecular Evidence for Occurrence of Tomato leaf curl New Delhi virus in Ash Gourd (Benincasa hispida) Germplasm Showing a Severe Yellow Stunt Disease in India.

Science.gov (United States)

Roy, Anirban; Spoorthi, P; Panwar, G; Bag, Manas Kumar; Prasad, T V; Kumar, Gunjeet; Gangopadhyay, K K; Dutta, M

2013-06-01

An evaluation of 70 accessions of ash gourd germplasm grown at National Bureau of Plant Genetic Resources, New Delhi, India during Kharif season (2010) showed natural occurrence of a yellow stunt disease in three accessions (IC554690, IC036330 and Pusa Ujjwal). A set of begomovirus specific primers used in PCR gave expected amplicon from all the symptomatic plants; however no betasatellite was detected. Complete genome of the begomovirus (DNA-A and DNA-B), amplified through rolling circle amplification, was cloned and sequenced. The begomovirus under study shared high sequence identities to different isolates of Tomato leaf curl New Delhi virus (ToLCNDV) and clustered with them. Among those isolates, the DNA-A and DNA-B of the present begomovirus isolate showed highest 99.6 and 96.8 % sequence identities, respectively with an isolate reported on pumpkin from India (DNA-A: AM286433, DNA-B: AM286435). Based on the sequence analysis, the begomovirus obtained from ash gourd was considered as an isolate of ToLCNDV. Thus, the present findings constitute the first report of occurrence of a new yellow stunt disease in ash gourd from India and demonstrated the association of ToLCNDV with the symptomatic samples. Occurrence of ToLCNDV in ash gourd germplasm not only adds up a new cucurbitaceous host of this virus but also raises the concern about the perpetuation of this virus in absence of its main host tomato and thus has an epidemiological relevance for understanding the rapid spread of this virus in tomato and other hosts in Indian sub-continent.

Genetic diversity of tomato-infecting Tomato yellow leaf curl virus (TYLCV) isolates in Korea.

Science.gov (United States)

Kim, Sue Hoon; Oh, Sung; Oh, Tae-Kyun; Park, Jae Sung; Kim, Sei Chang; Kim, Seong Hwan; Kim, Young Shik; Hong, Jeum Kyu; Sim, Sang-Yun; Park, Kwon Seo; Lee, Hwan Gu; Kim, Kyung Jae; Choi, Chang Won

2011-02-01

Epidemic outbreaks of Tomato yellow leaf curl virus (TYLCV) diseases occurred in greenhouse grown tomato (Solanum lycopersicum) plants of Busan (TYLCV-Bus), Boseong (TYLCV-Bos), Hwaseong (TYLCV-Hwas), Jeju Island (TYLCV-Jeju), and Nonsan (TYLCV-Nons) in Korea during 2008-2009. Tomato disease by TYLCV has never occurred in Korea before. We synthesized the full-length genomes of each TYLCV isolate from the tomato plants collected at each area and determined their nucleotides (nt) sequences and deduced the amino acids of six open reading frames in the genomes. TYLCV-Bus and -Bos genomes shared higher nt identities with four Japanese isolates -Ng, -Omu, -Mis, and -Miy. On the other hand, TYLCV-Hwas, -Jeju, and -Nons genomes shared higher nt identities with five Chinese isolates TYLCV-AH1, -ZJ3, -ZJHZ12, -SH2, -Sh10, and two Japanese isolates -Han and -Tosa. On the basis of a neighbor-joining tree, five Korean TYLCV isolates were separated into three clades. TYLCV-Bus and -Bos formed the first clade, clustering with four Japanese isolates TYLCV-Mis, -Omu, -Ng, and -Miy. TYLCV-Jeju and -Nons formed the second clade, clustering with two Chinese isolates -ZJHZ212 and -Sh10. TYLCV-Hwas was clustered with two Japanese isolates -Han and -Tosa and three Chinese isolates -AH1, -ZJ3, and -SH2. Two fragments that had a potentially recombinant origin were identified using the RDP, GENECONV, BootScan, MaxChi, Chimaera, SiScan, and 3Seq methods implemented in RDP3.41. On the basis of RDP analysis, all TYLCV isolates could originated from the interspecies recombination between TYLCV-Mld[PT] isolated from Portugal as a major parent and TYLCTHV-MM isolated from Myanmar as a minor parent.

Differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus.

Science.gov (United States)

He, Wen-Bo; Li, Jie; Liu, Shu-Sheng

2015-01-08

Plant viruses interact with their insect vectors directly and indirectly via host plants, and this tripartite interaction may produce fitness benefits to both the vectors and the viruses. Our previous studies show that the Middle East-Asia Minor 1 (MEAM1) species of the whitefly Bemisia tabaci complex improved its performance on tobacco plants infected by the Tomato yellow leaf curl China virus (TYLCCNV), which it transmits, although virus infection of the whitefly per se reduced its performance. Here, we use electrical penetration graph recording to investigate the direct and indirect effects of TYLCCNV on the feeding behaviour of MEAM1. When feeding on either cotton, a non-host of TYLCCNV, or uninfected tobacco, a host of TYLCCNV, virus-infection of the whiteflies impeded their feeding. Interestingly, when viruliferous whiteflies fed on virus-infected tobacco, their feeding activities were no longer negatively affected; instead, the virus promoted whitefly behaviour related to rapid and effective sap ingestion. Our findings show differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus, and help to unravel the behavioural mechanisms underlying a mutualistic relationship between an insect vector and a plant virus that also has features reminiscent of an insect pathogen.

Correlation of meteorological parameters and remotely sensed normalized difference vegetation index (NDVI) with cotton leaf curl virus (CLCV) in Multan

International Nuclear Information System (INIS)

Ahmed, A; Akhtar, A; Khalid, B; Shamim, A

2013-01-01

Climate change and weather has a profound effect on the spread of Cotton Leaf Curl Virus (CLCV) which is transmitted by whitefly. Climate change is altering temperature and precipitation patterns, resulting in the shift of some insect/pest from small population to large population thus effecting crops yield. To find out the relationship between the weather conditions, outburst of CLCV and changes in Normalized Difference Vegetation Index (NDVI) values due to the outburst of CLCV, a study was carried out for tehsil Multan. Data was acquired for the months of June, July, August and September for the year 2010. Regression analysis between CLCV and meteorological conditions as well as between CLCV and NDVI was performed. Meteorological parameters included temperature, humidity, precipitation, cloud cover, wind direction, pan evaporation and sunshine hours. NDVI values were calculated from SPOT satellite imagery (1km) using ArcMap10 and WinDisp v5.1. Correlation coefficients obtained in most of the cases were acceptable however the significance F and P-value were higher than their critical value at 95% level of significance. Therefore significant correlation was found only between CLCV and temperature and between CLCV and PAN evaporation during the month of July.

Spillover of Newcastle disease viruses from poultry to wild birds in Guangdong province, southern China.

Science.gov (United States)

Xiang, Bin; Han, Lujie; Gao, Pei; You, Renrong; Wang, Fumin; Xiao, Jiajie; Liao, Ming; Kang, Yinfeng; Ren, Tao

2017-11-01

Despite intensive vaccination programs in many countries, including China, Newcastle disease has been reported sporadically and is still a significant threat to the poultry industry in China. Newcastle disease virus (NDV) is infectious for at least 250 bird species, but the role of wild birds in virus epidemiology remains largely unknown. Fourteen NDV isolates were obtained from 2040 samples collected from wild birds or the environment in Guangdong province, southern China, from 2013 to 2015. The isolation rate was the highest in the period of wintering and lowest during the periods of spring migration, nesting, and postnesting. A maximum clade credibility phylogenetic analysis revealed that at least four genotypes circulate in southern China: three class II genotypes (II, VI, and IX) and one class I (1b). We also demonstrated that most isolates from wild birds were highly similar to isolates from poultry, and two isolates were linked to viruses from wild birds in northern China. These data suggested that wild birds could disseminate NDV and poultry-derived viruses may spillover to wild birds. Accordingly, vaccine development and poultry management strategies should be considered to prevent future NDV outbreaks, particularly given the strength of the poultry industry in developing countries, such as China. Copyright © 2017 Elsevier B.V. All rights reserved.

Enzootic genotype S of H9N2 avian influenza viruses donates internal genes to emerging zoonotic influenza viruses in China.

Science.gov (United States)

Gu, Min; Chen, Hongzhi; Li, Qunhui; Huang, Junqing; Zhao, Mingjun; Gu, Xiaobing; Jiang, Kaijun; Wang, Xiaoquan; Peng, Daxin; Liu, Xiufan

2014-12-05

Avian influenza viruses of subtype H9N2 are widely prevalent in poultry in many Asian countries, and the segmented nature of the viral genome results in multiple distinct genotypes via reassortment. In this study, genetic evolution of H9N2 viruses circulating in eastern China during 2007-2013 was analyzed. The results showed that the diversity of the gene constellations generated six distinct genotypes, in which a novel genotype (S) bearing the backbone of A/chicken/Shanghai/F/98-like viruses by acquiring A/quail/Hong Kong/G1/97-like polymerase basic subunit 2 and matrix genes has gradually established its ecological niche and been consistently prevalent in chicken flocks in eastern China since its first detection in 2007. Furthermore, genotype S possessed the peculiarity to donate most of its gene segments to other emerging influenza A viruses in China, including the novel reassortant highly pathogenic avian influenza H5N2, the 2013 novel H7N7, H7N9 and the latest reassortant H10N8 viruses, with potential threat to poultry industry and human health. Copyright © 2014 Elsevier B.V. All rights reserved.

Human Infection with Avian Influenza A(H7N9) Virus - China

Science.gov (United States)

... response operations Diseases Biorisk reduction Disease outbreak news Human infection with avian influenza A(H7N9) virus – China ... Region (SAR) notified WHO of a laboratory-confirmed human infection with avian influenza A(H7N9) virus and ...

The Whitefly Bemisia tabaci Knottin-1 Gene Is Implicated in Regulating the Quantity of Tomato Yellow Leaf Curl Virus Ingested and Transmitted by the Insect

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Aliza Hariton Shalev

2016-07-01

Full Text Available The whitefly Bemisia tabaci is a major pest to agricultural crops. It transmits begomoviruses, such as Tomato yellow leaf curl virus (TYLCV, in a circular, persistent fashion. Transcriptome analyses revealed that B. tabaci knottin genes were responsive to various stresses. Upon ingestion of tomato begomoviruses, two of the four knottin genes were upregulated, knot-1 (with the highest expression and knot-3. In this study, we examined the involvement of B. tabaci knottin genes in relation to TYLCV circulative transmission. Knottins were silenced by feeding whiteflies with knottin dsRNA via detached tomato leaves. Large amounts of knot-1 transcripts were present in the abdomen of whiteflies, an obligatory transit site of begomoviruses in their circulative transmission pathway; knot-1 silencing significantly depleted the abdomen from knot-1 transcripts. Knot-1 silencing led to an increase in the amounts of TYLCV ingested by the insects and transmitted to tomato test plants by several orders of magnitude. This effect was not observed following knot-3 silencing. Hence, knot-1 plays a role in restricting the quantity of virions an insect may acquire and transmit. We suggest that knot-1 protects B. tabaci against deleterious effects caused by TYLCV by limiting the amount of virus associated with the whitefly vector.

Suppression of cotton leaf curl disease symptoms in Gossypium hirsutum through over expression of host-encoded miRNAs.

Science.gov (United States)

Akmal, Mohd; Baig, Mirza S; Khan, Jawaid A

2017-12-10

Cotton leaf curl disease (CLCuD), a major factor resulting in the enormous yield losses in cotton crop, is caused by a distinct monopartite begomovirus in association with Cotton leaf curl Multan betasatellite (CLCuMB). Micro(mi)RNAs are known to regulate gene expression in eukaryotes, including antiviral defense in plants. In a previous study, we had computationally identified a set of cotton miRNAs, which were shown to have potential targets in the genomes of Cotton leaf curl Multan virus (CLCuMuV) and CLCuMB at multiple loci. In the current study, effect of Gossypium arboreum-encoded miRNAs on the genome of CLCuMuV and CLCuMB was investigated in planta. Two computationally predicted cotton-encoded miRNAs (miR398 and miR2950) that showed potential to bind multiple Open Reading Frames (ORFs; C1, C4, V1, and non- coding intergenic region) of CLCuMuV, and (βC1) of CLCuMB were selected. Functional validation of miR398 and miR2950 was done by overexpression approach in G. hirsutum var. HS6. A total of ten in vitro cotton plants were generated from independent events and subjected to biological and molecular analyses. Presence of the respective Precursor (pre)-miRNA was confirmed through PCR and Southern blotting, and their expression level was assessed by semi quantitative RT-PCR, Real Time quantitative PCR and northern hybridization in the PCR-positive lines. Southern hybridization revealed 2-4 copy integration of T-DNA in the genome of the transformed lines. Remarkably, expression of pre-miRNAs was shown up to 5.8-fold higher in the transgenic (T 0 ) lines as revealed by Real Time PCR. The virus resistance was monitored following inoculation of the transgenic cotton lines with viruliferous whitefly (Bemisia tabaci) insect vector. After inoculation, four of the transgenic lines remained apparently symptom free. While a very low titre of viral DNA could be detected by Rolling circle amplification, betasatellite responsible for symptom induction could not be detected

First Report of Hepatitis E Virus Infection in Sika Deer in China

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Xiao-Xuan Zhang

2015-01-01

Full Text Available Hepatitis E virus (HEV, a single stranded RNA, nonenveloped virus, belongs to the genus Hepevirus, in the family of Hepeviridae. In this study, 46 (5.43% out of the 847 serum samples from sika deer (Cervus nippon were detected as seropositive with hepatitis E virus (HEV by enzyme linked immunosorbent assay (ELISA. These samples were collected from Inner Mongolia and Jilin and Heilongjiang provinces in China, between October 2012 and October 2013. Seroprevalence of HEV infection in male and female deer was 4.82% and 6.52%, respectively. HEV seroprevalence in sika deer from different geographical locations varied from 3.13% to 6.73%. There was no significant difference in HEV seroprevalence between sika deer collected in autumn (5.65% and winter (4.85%. This is the first report of HEV seroprevalence in sika deer in China, which will provide foundation information for estimating the effectiveness of future measures to control HEV infection in sika deer in China and assessing the potential risk of humans infected with HEV after consumption of undercooked or raw meat from infected sika deer.

First report of hepatitis E virus infection in sika deer in China.

Science.gov (United States)

Zhang, Xiao-Xuan; Qin, Si-Yuan; Zhang, Yuan; Meng, Qing-Feng; Jiang, Jing; Yang, Gui-Lian; Zhao, Quan; Zhu, Xing-Quan

2015-01-01

Hepatitis E virus (HEV), a single stranded RNA, nonenveloped virus, belongs to the genus Hepevirus, in the family of Hepeviridae. In this study, 46 (5.43%) out of the 847 serum samples from sika deer (Cervus nippon) were detected as seropositive with hepatitis E virus (HEV) by enzyme linked immunosorbent assay (ELISA). These samples were collected from Inner Mongolia and Jilin and Heilongjiang provinces in China, between October 2012 and October 2013. Seroprevalence of HEV infection in male and female deer was 4.82% and 6.52%, respectively. HEV seroprevalence in sika deer from different geographical locations varied from 3.13% to 6.73%. There was no significant difference in HEV seroprevalence between sika deer collected in autumn (5.65%) and winter (4.85%). This is the first report of HEV seroprevalence in sika deer in China, which will provide foundation information for estimating the effectiveness of future measures to control HEV infection in sika deer in China and assessing the potential risk of humans infected with HEV after consumption of undercooked or raw meat from infected sika deer.

Flange Curling in Cold Formed Profiles

DEFF Research Database (Denmark)

Jönsson, Jeppe; Ramonas, Gediminas

2012-01-01

The non-linear flange curling phenomenon in cold formed profiles is the tendency of slender flanges to deform towards the neutral axis for increasing flexural curvature. Based on Braziers work, Winter proposed a simple engineering formula for determination of the local flange deformation towards...

Leaf curl diseases of two solanaceous species in Southwest Arabia are caused by a monopartite begomovirus evolutionarily most closely related to a species from the Nile Basin and unique suite of betasatellites

KAUST Repository

Idris, Ali

2012-10-01

The complete genome of 2780 bases was amplified using rolling circle amplification, and cloned, and sequenced for two distinct strains of the monopartite begomovirus Tomato leaf curl Sudan virus (ToLCSDV). The two strains shared 86-91% identity with the previously described ToLCSDV from the Nile Basin, and 90-91% identity with one another. One strain was cloned from symptomatic tomato plants from Tihamah (ToLCSDV-YE[YE:Tih:05]) while the other was cloned from symptomatic tobacco plants collected from Wadi Hadramaut (ToLCSDV-YE[YE:Had:89]). A distinct full-length betasatellite molecule (1352 bases) was cloned from the respective field-infected tomato and tobacco plants. Agro-inoculation of tomato and Nicotiana benthamiana plants with cloned partial tandem repeats of ToLCSDV-YE[YE:Tih11:05]) and the associated betasatellite, Tomato leaf curl Yemen betasatellite (ToLCYEB-[Tih:tom:137:05]), resulted in the reproduction of leaf curl disease symptoms in test plants like those observed in the field-infected plants. The betasatellite contributed to symptom severity in N. benthamiana test plants when it was co-inoculated with ToLCSDV-YE, compared to the milder symptoms that were observed in tobacco plants infected with the helper virus alone. © 2012 Elsevier B.V.

Leaf curl diseases of two solanaceous species in Southwest Arabia are caused by a monopartite begomovirus evolutionarily most closely related to a species from the Nile Basin and unique suite of betasatellites

KAUST Repository

Idris, Ali; Abdullah, N.; Brown, Judith K.

2012-01-01

The complete genome of 2780 bases was amplified using rolling circle amplification, and cloned, and sequenced for two distinct strains of the monopartite begomovirus Tomato leaf curl Sudan virus (ToLCSDV). The two strains shared 86-91% identity with the previously described ToLCSDV from the Nile Basin, and 90-91% identity with one another. One strain was cloned from symptomatic tomato plants from Tihamah (ToLCSDV-YE[YE:Tih:05]) while the other was cloned from symptomatic tobacco plants collected from Wadi Hadramaut (ToLCSDV-YE[YE:Had:89]). A distinct full-length betasatellite molecule (1352 bases) was cloned from the respective field-infected tomato and tobacco plants. Agro-inoculation of tomato and Nicotiana benthamiana plants with cloned partial tandem repeats of ToLCSDV-YE[YE:Tih11:05]) and the associated betasatellite, Tomato leaf curl Yemen betasatellite (ToLCYEB-[Tih:tom:137:05]), resulted in the reproduction of leaf curl disease symptoms in test plants like those observed in the field-infected plants. The betasatellite contributed to symptom severity in N. benthamiana test plants when it was co-inoculated with ToLCSDV-YE, compared to the milder symptoms that were observed in tobacco plants infected with the helper virus alone. © 2012 Elsevier B.V.

Biodiversity and evolution of Imjin virus and Thottapalayam virus in Crocidurinae shrews in Zhejiang Province, China.

Science.gov (United States)

Lin, Xian-Dan; Zhou, Run-Hong; Fan, Fei-Neng; Ying, Xu-Hua; Sun, Xiao-Yu; Wang, Wen; Holmes, Edward C; Zhang, Yong-Zhen

2014-08-30

The recent discovery of numerous hantaviruses in insectivores has provided a new view of hantavirus biodiversity and evolution. To determine the presence and genetic diversity of Imjin virus (MJNV) and Thottapalayam virus (TPMV) in insectivores in Zhejiang Province, China, we captured and performed virus screening of 32 Ussuri white-toothed shrews (Crocidura lasiura) and 105 Asian house shrews (Suncus murinus) in different coastal regions. Hantavirus genome (S, M, and L segments) sequences were successfully recovered from one Ussuri white-toothed shrew and seven Asian house shrews. Phylogenetic analysis revealed that the virus carried by the Ussuri white-toothed shrew was most closely related to MJNV, but with >15% nucleotide sequence difference, suggesting that it represents a new subtype. The hantaviruses carried by Asian house shrews were closely related to the TPMV variants found in the same geographic area, but more distantly related to those sampled in India and Nepal. Additionally, the TPMV sequences obtained in this study, as well as those found previously in this area, could be divided into three lineages reflecting their geographic origins, indicative of largely allopatric evolution. Overall, our data highlights the high genetic diversity of insectivore-borne hantaviruses in China, suggesting that more may be discovered in the future. Copyright © 2014 Elsevier B.V. All rights reserved.

No MERS-CoV but positive influenza viruses in returning Hajj pilgrims, China, 2013–2015

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Xuezheng Ma

2017-11-01

Full Text Available Abstract Background There is global health concern that the mass movement of pilgrims to and from Mecca annually could contribute to the international spread of Middle East Respiratory Syndrome Coronavirus (MERS-CoV. In China, about 11,000 Muslim pilgrims participate in the Hajj gathering in Mecca annually. This is the first report of MERS-CoV and respiratory virus molecular screening of returning pilgrims at points of entry in China from 2013 to 2015. Methods and results A total of 847 returning Hajj pilgrims participated in this study. The test results indicated that of the travelers, 34 tested positive for influenza A virus, 14 for influenza B virus, 4 for metapneumo virus, 2 for respiratory syncytial virus, and 3 for human coronavirus. There was a significant difference in the rates of positive and negative influenza virus tests between Hajj pilgrims with symptoms and those without. The detection rates of influenza virus were not significantly different among the three years studied, at 5.3, 6.0 and 6.3% for 2013, 2014 and 2015, respectively. Discussion and conclusion The MERS-CoV and respiratory viruses detection results at points of entry in China from 2013 to 2015 indicated that there were no MERS-CoV infection but a 5.7% positive influenza viruses in returning Chinese pilgrims.

[Clinical analysis of two cases of imported children Zika virus infection in China].

Science.gov (United States)

Zheng, C G; Xu, Y; Jiang, H Q; Yin, Y X; Zhang, J H; Zhu, W J; Liang, X J; Chen, M X; Ye, J W; Tan, L M; Luo, D; Gong, S T

2016-05-01

To analyze the clinical characteristics, outcome and diagnosis of two cases of imported children Zika virus infection in China. A retrospective analysis was performed on clinical characteristics, treatment and outcome of two cases of imported children with Zika virus infection in February 2016 in Enping People's Hospital of Guangdong. Two cases of children with imported Zika virus infection resided in an affected area of Venezuela, 8-year-old girl and her 6 year-old brother. The main findings on physical examination included the following manifestations: fever, rash, and conjunctivitis. The rash was first limited to the abdomen, but extended to the torso, neck and face, and faded after 3-4 d. The total number of white blood cells was not high and liver function was normal. The diagnosis of two cases of Zika virus infection was confirmed by the expert group of Guangdong Provincial Center for Disease Control and Prevention, according to the epidemiological history, clinical manifestations and Zika virus nucleic acid detection results.Treatment of Zika virus infection involves supportive care. Two Zika virus infection children had a relatively benign outcome. At present, Zika virus infection in children is an imported disease in China. No specific therapy is available for this disease. Information on long-term outcomes among infants and children with Zika virus disease is limited, routine pediatric care is advised for these infants and children.

Single endemic genotype of measles virus continuously circulating in China for at least 16 years.

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Yan Zhang

Full Text Available The incidence of measles in China from 1991 to 2008 was reviewed, and the nucleotide sequences from 1507 measles viruses (MeV isolated during 1993 to 2008 were phylogenetically analyzed. The results showed that measles epidemics peaked approximately every 3 to 5 years with the range of measles cases detected between 56,850 and 140,048 per year. The Chinese MeV strains represented three genotypes; 1501 H1, 1 H2 and 5 A. Genotype H1 was the predominant genotype throughout China continuously circulating for at least 16 years. Genotype H1 sequences could be divided into two distinct clusters, H1a and H1b. A 4.2% average nucleotide divergence was found between the H1a and H1b clusters, and the nucleotide sequence and predicted amino acid homologies of H1a viruses were 92.3%-100% and 84.7%-100%, H1b were 97.1%-100% and 95.3%-100%, respectively. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Cluster H1a and H1b viruses were co-circulating during 1993 to 2005, while no H1b viruses were detected after 2005 and the transmission of that cluster has presumably been interrupted. Analysis of the nucleotide and predicted amino acid changes in the N proteins of H1a and H1b viruses showed no evidence of selective pressure. This study investigated the genotype and cluster distribution of MeV in China over a 16-year period to establish a genetic baseline before MeV elimination in Western Pacific Region (WPR. Continuous and extensive MeV surveillance and the ability to quickly identify imported cases of measles will become more critical as measles elimination goals are achieved in China in the near future. This is the first report that a single endemic genotype of measles virus has been found to be continuously circulating in one country for at least 16 years.

EFFECT OF THE SHOULDER POSITION ON THE BICEPS BRACHII EMG IN DIFFERENT DUMBBELL CURLS

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Taian M.M. Vieira

2009-03-01

Full Text Available Incline Dumbbell Curl (IDC and Dumbbell Preacher Curl (DPC are two variations of the standard Dumbbell Biceps Curl (DBC, generally applied to optimize biceps brachii contribution for elbow flexion by fixing shoulder at a specific angle. The aim of this study is to identify changes in the neuromuscular activity of biceps brachii long head for IDC, DPC and DBC exercises, by taking into account the changes in load moment arm and muscle length elicited by each dumbbell curl protocol. A single cycle (concentric-eccentric of DBC, IDC and DPC, was applied to 22 subjects using a submaximal load of 40% estimated from an isometric MVC test. The neuromuscular activity of biceps brachii long head was compared by further partitioning each contraction into three phases, according to individual elbow joint range of motion. Although all protocols elicited a considerable level of activation of the biceps brachii muscle (at least 50% of maximum RMS, the contribution of this muscle for elbow flexion/extension varied among exercises. The submaximal elbow flexion (concentric elicited neuro muscular activity up to 95% of the maximum RMS value during the final phase of IDC and DBC and 80% for DPC at the beginning of the movement. All exercises showed significant less muscle activity for the elbow extension (eccentric. The Incline Dumbbell Curl and the classical Dumbbell Biceps Curl resulted in similar patterns of biceps brachii activation for the whole range of motion, whereas Dumbbell Preacher Curl elicited high muscle activation only for a short range of elbow joint angle

Genome characterization, antigenicity and pathogenicity of a novel infectious bronchitis virus type isolated from south China.

Science.gov (United States)

Jiang, Lei; Zhao, Wenjun; Han, Zongxi; Chen, Yuqiu; Zhao, Yan; Sun, Junfeng; Li, Huixin; Shao, Yuhao; Liu, Liangliang; Liu, Shengwang

2017-10-01

In 2014, three infectious bronchitis virus (IBV) strains, designated as γCoV/ck/China/I0111/14, γCoV/ck/China/I0114/14 and γCoV/ck/China/I0118/14, were isolated and identified from chickens suspected to be infected with IBV in Guangxi province, China. Based upon data arising from S1 sequence and phylogenetic analyses, the three IBV isolates were genetically different from other known IBV types, which represented a novel genotype (GI-29). Virus cross-neutralization tests, using γCoV/ck/China/I0111/14 as a representative, showed that genotype GI-29 was antigenically different from all other known IBV types, thus representing a novel serotype. Complete genomic analysis showed that GI-29 type viruses were closely related to and might originate from a GX-YL5-like virus by accumulation of substitutions in multiple genes. These GI-29 viral genomes are still evolving and diverging, particularly in the 3' region, although we cannot rule out the possibility of recombination events occurring. For isolate γCoV/ck/China/I0114/14, we found that recombination events had occurred between nsps 2 and 3 in gene 1 which led to the introduction of a 4/91 gene fragment into the γCoV/ck/China/I0114/14 viral genome. In addition, we found that the GI-29 type γCoV/ck/China/I0111/14 isolate was a nephropathogenic strain and high pathogenic to 1-day-old specific pathogen-free (SPF) chickens although cystic oviducts were not observed in the surviving layer chickens challenged with γCoV/ck/China/I0111/14 isolate. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolation of Irkut virus from a Murina leucogaster bat in China.

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Ye Liu

Full Text Available BACKGROUND AND OBJECTIVES: Bats are recognized as a major reservoir of lyssaviruses; however, no bat lyssavirus has been isolated in Asia except for Aravan and Khujand virus in Central Asia. All Chinese lyssavirus isolates in previous reports have been of species rabies virus, mainly from dogs. Following at least two recent bat-associated human rabies-like cases in northeast China, we have initiated a study of the prevalence of lyssaviruses in bats in Jilin province and their public health implications. A bat lyssavirus has been isolated and its pathogenicity in mice and genomic alignment have been determined. RESULTS: We report the first isolation of a bat lyssavirus in China, from the brain of a northeastern bat, Murina leucogaster. Its nucleoprotein gene shared 92.4%/98.9% (nucleotide and 92.2%/98.8% (amino acid identity with the two known Irkut virus isolates from Russia, and was designated IRKV-THChina12. Following intracranial and intramuscular injection, IRKV-THChina12 produced rabies-like symptoms in adult mice with a short inoculation period and high mortality. Nucleotide sequence analysis showed that IRKV-THChina12 has the same genomic organization as other lyssaviruses and its isolation provides an independent origin for the species IRKV. CONCLUSIONS: We have identified the existence of a bat lyssavirus in a common Chinese bat species. Its high pathogenicity in adult mice suggests that public warnings and medical education regarding bat bites in China should be increased, and that surveillance be extended to provide a better understanding of Irkut virus ecology and its significance for public health.

Epidemiologic and genetic characteristics of mumps viruses isolated in China from 1995 to 2010.

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Cui, Aili; Zhu, Zhen; Chen, Meng; Zheng, Huanying; Liu, Leng; Wang, Yan; Ma, Yan; Wang, Changyin; Fang, Xueqiang; Li, Ping; Guan, Ronghui; Wang, Shuang; Zhou, Jianhui; Zheng, Lei; Gao, Hui; Ding, Zhengrong; Li, Liqun; Bo, Fang; Sun, Zhaodan; Zhang, Zhenying; Feng, Daxing; He, Jilan; Chen, Hui; Jin, Li; Rota, Paul A; Xu, Wenbo

2014-01-01

The epidemiologic and genetic characteristics of mumps viruses detected in China from 1995 to 2010 were analyzed in this study. Mumps remains endemic in China with a high overall incidence rate. The incidence of mumps in Western China was higher than that in other regions of the country. Each year, most of mumps cases occurred between April and July, but a small peak also occurred in November and December. Mumps cases primarily affected the under 15 year old age group. Virologic data demonstrated that genotype F was the predominant circulating genotype throughout China for at least 15 years and no other genotype was detected between 1995 and 2010. Analysis of sequence data from the small hydrophobic (SH) gene indicated that multiple transmission chains of genotype F were found in various provinces of China, with no apparent chronologic and geographic restriction. This is the first report describing the epidemiology of mumps and genetic characterization of mumps viruses at the national level in China. Copyright © 2013 Elsevier B.V. All rights reserved.

Morphologic and Molecular Characterization of a Strain of Zika Virus Imported into Guangdong, China.

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Shufen Li

Full Text Available The recent outbreaks of Zika virus (ZIKV disease have caused worldwide concerns. Guangdong province is one of the commercial centers in China and communicates frequently with the epidemic areas. To date, 65.2% of the ZIKV infection cases in China were imported via port of entry in Guangdong. The continuous surveillance of imported cases is crucial for the prevention and control of potential ZIKV infection outbreak in China. In this study, a strain of ZIKV was isolated from the serum of a 6-year-old child returning from Venezuela. The morphology of the ZIKV was analyzed in vivo and in vitro by electron microscopy, and clusters of virus particles were found in the loose cytoplasmic membrane structures. The genomic sequence of the isolated ZIKV was determined, and the alignment and phylogenetic analysis identified one unique amino acid substitution occurring in the non-structural protein 4B (NS4B, and the isolated virus belonged to the Asian lineage.

First Report of Hepatitis E Virus Infection in Sika Deer in China

OpenAIRE

Zhang, Xiao-Xuan; Qin, Si-Yuan; Zhang, Yuan; Meng, Qing-Feng; Jiang, Jing; Yang, Gui-Lian; Zhao, Quan; Zhu, Xing-Quan

2015-01-01

Hepatitis E virus (HEV), a single stranded RNA, nonenveloped virus, belongs to the genus Hepevirus, in the family of Hepeviridae. In this study, 46 (5.43%) out of the 847 serum samples from sika deer (Cervus nippon) were detected as seropositive with hepatitis E virus (HEV) by enzyme linked immunosorbent assay (ELISA). These samples were collected from Inner Mongolia and Jilin and Heilongjiang provinces in China, between October 2012 and October 2013. Seroprevalence of HEV infection in male a...

The antigenic property of the H5N1 avian influenza viruses isolated in central China

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Zou Wei

2012-08-01

Full Text Available Abstract Background Three influenza pandemics outbroke in the last century accompanied the viral antigen shift and drift, resulting in the change of antigenic property and the low cross protective ability of the existed antibody to the newly emerged pandemic virus, and eventually the death of millions of people. The antigenic characterizations of the viruses isolated in central China in 2004 and 2006–2007 were investigated in the present study. Results Hemagglutinin inhibition assay and neutralization assay displayed differential antigenic characteristics of the viruses isolated in central China in two periods (2004 and 2006–2007. HA genes of the viruses mainly located in two branches in phylogeny analysis. 53 mutations of the deduced amino acids of the HA genes were divided into 4 patterns. Mutations in pattern 2 and 3 showed the main difference between viruses isolated in 2004 and 2006–2007. Meanwhile, most amino acids in pattern 2 and 3 located in the globular head of the HA protein, and some of the mutations evenly distributed at the epitope sites. Conclusions The study demonstrated that a major antigenic drift had occurred in the viruses isolated in central China. And monitoring the antigenic property should be the priority in preventing the potential pandemic of H5N1 avian influenza virus.

Single Endemic Genotype of Measles Virus Continuously Circulating in China for at Least 16 Years

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Wang, Huiling; Zhu, Zhen; Ji, Yixin; Liu, Chunyu; Zhang, Xiaojie; Sun, Liwei; Zhou, Jianhui; Lu, Peishan; Hu, Ying; Feng, Daxing; Zhang, Zhenying; Wang, Changyin; Fang, Xueqiang; Zheng, Huanying; Liu, Leng; Sun, Xiaodong; Tang, Wei; Wang, Yan; Liu, Yan; Gao, Hui; Tian, Hong; Ma, Jiangtao; Gu, Suyi; Wang, Shuang; Feng, Yan; Bo, Fang; Liu, Jianfeng; Si, Yuan; Zhou, Shujie; Ma, Yuyan; Wu, Shengwei; Zhou, Shunde; Li, Fangcai; Ding, Zhengrong; Yang, Zhaohui; Rota, Paul A.; Featherstone, David; Jee, Youngmee; Bellini, William J.; Xu, Wenbo

2012-01-01

The incidence of measles in China from 1991 to 2008 was reviewed, and the nucleotide sequences from 1507 measles viruses (MeV) isolated during 1993 to 2008 were phylogenetically analyzed. The results showed that measles epidemics peaked approximately every 3 to 5 years with the range of measles cases detected between 56,850 and 140,048 per year. The Chinese MeV strains represented three genotypes; 1501 H1, 1 H2 and 5 A. Genotype H1 was the predominant genotype throughout China continuously circulating for at least 16 years. Genotype H1 sequences could be divided into two distinct clusters, H1a and H1b. A 4.2% average nucleotide divergence was found between the H1a and H1b clusters, and the nucleotide sequence and predicted amino acid homologies of H1a viruses were 92.3%–100% and 84.7%–100%, H1b were 97.1%–100% and 95.3%–100%, respectively. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Cluster H1a and H1b viruses were co-circulating during 1993 to 2005, while no H1b viruses were detected after 2005 and the transmission of that cluster has presumably been interrupted. Analysis of the nucleotide and predicted amino acid changes in the N proteins of H1a and H1b viruses showed no evidence of selective pressure. This study investigated the genotype and cluster distribution of MeV in China over a 16-year period to establish a genetic baseline before MeV elimination in Western Pacific Region (WPR). Continuous and extensive MeV surveillance and the ability to quickly identify imported cases of measles will become more critical as measles elimination goals are achieved in China in the near future. This is the first report that a single endemic genotype of measles virus has been found to be continuously circulating in one country for at least 16 years. PMID:22532829

Molecular Identification of Weed hosts of Tomato yellow leaf curl virus in southeast of Kerman Province

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Kh. Salari

2016-02-01

Full Text Available Introduction Tomato yellow leaf curl virus, TYLCV belongs to the family Geminiviridae and Begomovirus genus (27. In recent years, extensive damage to tomatoes and cucurbits plants in the south and the southeast of Iran has arrived (23. This virus family have circular, and single-stranded DNA genome and are widespread in tropical and subtropical areas (30. They are infected several plant species with economic importance. Begomoviruses are dicot-infecting, whitefly-transmitted viruses with a genome comprised of one or two molecules DNA (5. Up to now, studies have been performed to evaluate the status of distribution, and identification of natural host and assess the genetic diversity, but there is not a comprehensive review about its weed hosts yet. Materials and Methods In this research, The weeds from margins and inside greenhouses and farms of tomato and cucurbit in severely infected areas including Manoojan, Kahnooj, Faryab, Anbrabad and Jiroft to identify weed hosts of the virus in nature, were collected. Identification of collected samples were conducted by botanical specialists. Total DNAs were extracted from leaves according to the method of zhang et al. (1998 and stored at -20 oC. Identification of infected samples were carried out by PCR using degenerate primer pairs PCRv 181/Bc that direct the amplification of˷ 550 bp fragment of mono – and bipartite begomoviruses genome comprising the C-terminal portion of the intergenic region (IR N-terminal portion of the CPgene. PCR were performed in 25 µl reaction volumes containing 1 µl of template DNA, o.5 µl of Taq DNA polymerase Sinaclon (IRAN, 1.2 µl MgCl2, 0.5 µl dNTPs. 1 µM of each forward and reverse primers, 4.3 µl of 10× reaction buffer and 15.5 distilled water. The amplification were performed using a peqSTAR 96x Termal Cycler (Peqlabe, Germany. PCR conditions consisted of initial denaturing 94 oC for 3 min followed by 30 cycles of denaturation at 94 oC for 50s, annealing at

First Molecular Characterization of Feline Immunodeficiency Virus in Domestic Cats from Mainland China.

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Zhang, Jilei; Wang, Liang; Li, Jing; Kelly, Patrick; Price, Stuart; Wang, Chengming

2017-01-01

The feline immunodeficiency virus (FIV) is a retrovirus of the Lentivirus genus that was initially isolated from a colony of domestic cats in California in 1986 and has now been recognized as a common feline pathogen worldwide. To date, there is only one recent serology-based report on FIV in mainland China which was published in 2016. We designed this study to investigate the molecular prevalence and diversity of feline immunodeficiency virus (FIV) in domestic cats from mainland China. We studied the prevalence of FIV in whole blood samples of 615 domestic cats in five cities (Beijing, Guangzhou, Nanjing, Shanghai and Yangzhou) of mainland China and examined them using FRET-PCR (Fluorescence Resonance Energy Transfer-Polymerase Chain Reaction) and regular PCRs for the gag and env genes. Overall, 1.3% (8/615) of the cats were positive for provirus DNA with nucleotide analysis using PCRs for the gag and env sequences showing the cats were infected with FIV subtype A. This is the first molecular characterization of FIV in mainland China and the first description of subtype A in continental Asia.

Oncorine, the World First Oncolytic Virus Medicine and its Update in China.

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Liang, Min

2018-01-01

The oncolytic viruses now hold a promise of new therapeutic strategy for cancer. Its concept has inspired a wave of commercial research and development activities for the products of this category in China since 1998. The first commercialized oncolytic virus product in the world, Oncorine (H101), developed by Shanghai Sunway Biotech Co., Ltd since 1999, was approved by Chinese SFDA in November, 2005 for nasopharyngeal carcinoma in combination with chemotherapy after the phase III clinical trial, and finally acquired GMP certificate in August, 2006. This review introduces how Oncorine was successfully developed in China, and how the Chinese market responded after it was launched into the market in 2006. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Establishment of an H6N2 Influenza Virus Lineage in Domestic Ducks in Southern China ▿ †

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Huang, K.; Bahl, J.; Fan, X. H.; Vijaykrishna, D.; Cheung, C. L.; Webby, R. J.; Webster, R. G.; Chen, H.; Smith, Gavin J. D.; Peiris, J. S. M.; Guan, Y.

2010-01-01

Multiple reassortment events between different subtypes of endemic avian influenza viruses have increased the genomic diversity of influenza viruses circulating in poultry in southern China. Gene exchange from the natural gene pool to poultry has contributed to this increase in genetic diversity. However, the role of domestic ducks as an interface between the natural gene pool and terrestrial poultry in the influenza virus ecosystem has not been fully characterized. Here we phylogenetically and antigenically analyzed 170 H6 viruses isolated from domestic ducks from 2000 to 2005 in southern China, which contains the largest population of domestic ducks in the world. Three distinct hemagglutinin lineages were identified. Group I contained the majority of isolates with a single internal gene complex and was endemic in domestic ducks in Guangdong from the late 1990s onward. Group II was derived from reassortment events in which the surface genes of group I viruses were replaced with novel H6 and N2 genes. Group III represented H6 viruses that undergo frequent reassortment with multiple virus subtypes from the natural gene pool. Surprisingly, H6 viruses endemic in domestic ducks and terrestrial poultry seldom reassort, but gene exchanges between viruses from domestic ducks and migratory ducks occurred throughout the surveillance period. These findings suggest that domestic ducks in southern China mediate the interaction of viruses between different gene pools and facilitate the generation of novel influenza virus variants circulating in poultry. PMID:20463062

Molecular characterization and phylogenetic analysis of infectious bursal disease viruses isolated from chicken in South China in 2011.

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Liu, Di; Zhang, Xiang-Bin; Yan, Zhuan-Qiang; Chen, Feng; Ji, Jun; Qin, Jian-Ping; Li, Hai-Yan; Lu, Jun-Peng; Xue, Yu; Liu, Jia-Jia; Xie, Qing-Mei; Ma, Jing-Yun; Xue, Chun-Yi; Bee, Ying-Zuo

2013-06-01

Infectious bursal disease virus (IBDV) is a double-stranded RNA virus that causes immunosuppressive disease in young chickens. Thousands of cases of IBDV infection are reported each year in South China, and these infections can result in considerable economic losses to the poultry industry. To monitor variations of the virus during the outbreaks, 30 IBDVs were identified from vaccinated chicken flocks from nine provinces in South China in 2011. VP2 fragments from different virus strains were sequenced and analyzed by comparison with the published sequences of IBDV strains from China and around the world. Phylogenetic analysis of hypervariable regions of the VP2 (vVP2) gene showed that 29 of the isolates were very virulent (vv) IBDVs, and were closely related to vvIBDV strains from Europe and Asia. Alignment analysis of the deduced amino acid (aa) sequences of vVP2 showed the 29 vv isolates had high uniformity, indicated low variability and slow evolution of the virus. The non-vvIBDV isolate JX2-11 was associated with higher than expected mortality, and had high deduced aa sequence similarity (99.2 %) with the attenuated vaccine strain B87 (BJ). The present study has demonstrated the continued circulation of IBDV strains in South China, and emphasizes the importance of reinforcing IBDV surveillance.

Apparatus and method for transfer of information by means of a curl-free magnetic vector potential field

International Nuclear Information System (INIS)

Gelinas, R.C.

1984-01-01

A system for transmission of information using a curl-free magnetic vector potential radiation field. The system includes current-carrying apparatus for generating a magnetic vector potential field with a curl-free component coupled to apparatus for modulating the current applied to the field generating apparatus. Receiving apparatus includes a detector with observable properties that vary with the application of an applied curl-free magnetic vector potential field. Analyzing apparatus for determining the information content of modulation imposed on the curl-free vector potential field can be established in materials that are not capable of transmitting more common electromagnetic radiation

Competence of Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus Mosquitoes as Zika Virus Vectors, China

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Liu, Zhuanzhuan; Zhou, Tengfei; Lai, Zetian; Zhang, Zhenhong; Jia, Zhirong; Zhou, Guofa; Williams, Tricia; Xu, Jiabao; Gu, Jinbao; Zhou, Xiaohong; Lin, Lifeng; Yan, Guiyun

2017-01-01

In China, the prevention and control of Zika virus disease has been a public health threat since the first imported case was reported in February 2016. To determine the vector competence of potential vector mosquito species, we experimentally infected Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquitoes and determined infection rates, dissemination rates, and transmission rates. We found the highest vector competence for the imported Zika virus in Ae. aegypti mosquitoes, some susceptibility of Ae. albopictus mosquitoes, but no transmission ability for Cx. quinquefasciatus mosquitoes. Considering that, in China, Ae. albopictus mosquitoes are widely distributed but Ae. aegypti mosquito distribution is limited, Ae. albopictus mosquitoes are a potential primary vector for Zika virus and should be targeted in vector control strategies. PMID:28430562

Competence of Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus Mosquitoes as Zika Virus Vectors, China.

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Liu, Zhuanzhuan; Zhou, Tengfei; Lai, Zetian; Zhang, Zhenhong; Jia, Zhirong; Zhou, Guofa; Williams, Tricia; Xu, Jiabao; Gu, Jinbao; Zhou, Xiaohong; Lin, Lifeng; Yan, Guiyun; Chen, Xiao-Guang

2017-07-01

In China, the prevention and control of Zika virus disease has been a public health threat since the first imported case was reported in February 2016. To determine the vector competence of potential vector mosquito species, we experimentally infected Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquitoes and determined infection rates, dissemination rates, and transmission rates. We found the highest vector competence for the imported Zika virus in Ae. aegypti mosquitoes, some susceptibility of Ae. albopictus mosquitoes, but no transmission ability for Cx. quinquefasciatus mosquitoes. Considering that, in China, Ae. albopictus mosquitoes are widely distributed but Ae. aegypti mosquito distribution is limited, Ae. albopictus mosquitoes are a potential primary vector for Zika virus and should be targeted in vector control strategies.

Neuraminidase inhibitor susceptibility profile of human influenza viruses during the 2016-2017 influenza season in Mainland China.

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Huang, Weijuan; Cheng, Yanhui; Li, Xiyan; Tan, Minju; Wei, Hejiang; Zhao, Xiang; Xiao, Ning; Dong, Jie; Wang, Dayan

2018-06-01

To understand the current situation of antiviral-resistance of influenza viruses to neuraminidase inhibitors (NAIs) in Mainland China, The antiviral-resistant surveillance data of the circulating influenza viruses in Mainland China during the 2016-2017 influenza season were analyzed. The total 3215 influenza viruses were studied to determine 50% inhibitory concentration (IC 50 ) for oseltamivir and zanamivir using a fluorescence-based assay. Approximately 0.3% (n = 10) of viruses showed either highly reduced inhibition (HRI) or reduced inhibition (RI) against at least one NAI. The most common neuraminidase (NA) amino acid substitution was H275Y in A (H1N1)pdm09 virus, which confers HRI by oseltamivir. Two A (H1N1)pdm09 viruses contained a new NA amino acid substitution respectively, S110F and D151E, which confers RI by oseltamivir or/and zanamivir. Two B/Victoria-lineage viruses harbored a new NA amino acid substitution respectively, H134Q and S246P, which confers RI by zanamivir. One B/Victoria-lineage virus contained dual amino acid substitution NA P124T and V422I, which confers HRI by zanamivir. One B/Yamagata-lineage virus was a reassortant virus that haemagglutinin (HA) from B/Yamagata-lineage virus and NA from B/Victoria-lineage virus, defined as B/Yamagata-lineage virus confers RI by oseltamivir, but as B/Victoria-lineage virus confers normal inhibition by oseltamivir. All new substitutions that have not been reported before, the correlation of these substitutions and observed changes in IC 50 should be further assessed. During the 2016-2017 influenza season in Mainland China the majority tested viruses were susceptible to oseltamivir and zanamivir. Hence, NAIs remain the recommended antiviral for treatment and prophylaxis of influenza virus infections. Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Genetic Characterization of the Hemagglutinin Genes of Wild-Type Measles Virus Circulating in China, 1993–2009

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Zhu, Zhen; Liu, Chunyu; Mao, Naiying; Ji, Yixin; Wang, Huiling; Jiang, Xiaohong; Li, Chongshan; Tang, Wei; Feng, Daxing; Wang, Changyin; Zheng, Lei; Lei, Yue; Ling, Hua; Zhao, Chunfang; Ma, Yan; He, Jilan; Wang, Yan; Li, Ping; Guan, Ronghui; Zhou, Shujie; Zhou, Jianhui; Wang, Shuang; Zhang, Hong; Zheng, Huanying; Liu, Leng; Ma, Hemuti; Guan, Jing; Lu, Peishan; Feng, Yan; Zhang, Yanjun; Zhou, Shunde; Xiong, Ying; Ba, Zhuoma; Chen, Hui; Yang, Xiuhui; Bo, Fang; Ma, Yujie; Liang, Yong; Lei, Yake; Gu, Suyi; Liu, Wei; Chen, Meng; Featherstone, David; Jee, Youngmee; Bellini, William J.; Rota, Paul A.; Xu, Wenbo

2013-01-01

Background China experienced several large measles outbreaks in the past two decades, and a series of enhanced control measures were implemented to achieve the goal of measles elimination. Molecular epidemiologic surveillance of wild-type measles viruses (MeV) provides valuable information about the viral transmission patterns. Since 1993, virologic surveillnace has confirmed that a single endemic genotype H1 viruses have been predominantly circulating in China. A component of molecular surveillance is to monitor the genetic characteristics of the hemagglutinin (H) gene of MeV, the major target for virus neutralizing antibodies. Principal Findings Analysis of the sequences of the complete H gene from 56 representative wild-type MeV strains circulating in China during 1993–2009 showed that the H gene sequences were clustered into 2 groups, cluster 1 and cluster 2. Cluster1 strains were the most frequently detected cluster and had a widespread distribution in China after 2000. The predicted amino acid sequences of the H protein were relatively conserved at most of the functionally significant amino acid positions. However, most of the genotype H1 cluster1 viruses had an amino acid substitution (Ser240Asn), which removed a predicted N-linked glycosylation site. In addition, the substitution of Pro397Leu in the hemagglutinin noose epitope (HNE) was identified in 23 of 56 strains. The evolutionary rate of the H gene of the genotype H1 viruses was estimated to be approximately 0.76×10−3 substitutions per site per year, and the ratio of dN to dS (dN/dS) was measles in China. PMID:24073194

Identification and application of biocontrol agents against Cotton leaf curl virus disease in Gossypium hirsutum under greenhouse conditions

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Memoona Ramzan

2016-05-01

Full Text Available Biological control is a novel approach in crop protection. Bacteria, such as Bacillus spp. and Pseudomonas spp., are reported for this purpose and some of their products are already commercially available. In this study, the rhizosphere and phyllosphere of healthy cotton plants were used as a source of bacterial isolates with properties of potential biocontrol agents. The isolates were screened for phosphate solubilization activity, indole acetic acid (IAA production and antifungal activity. Two isolates, S1HL3 and S1HL4, showed phosphate solubilization and IAA production simultaneously, while another two, JS2HR4 and JS3HR2, demonstrated potential to inhibit fungal pathogens. These bacteria were identified as Pseudomonas aeruginosa (S1HL3, Burkholderia sp. (S1HL4 and Bacillus sp. (JS2HR4 and JS3HR2 based on biochemical and molecular characteristics. The isolates were tested against Cotton leaf curl virus (CLCuV in greenhouse conditions, both as individual bacterial isolates and consortia. Treated plants were healthy as compared to control plants, where up to 74% of the plants were symptomatic for CLCuV infection. Maximum inhibition of CLCuV was observed in the plants treated with a mixture of bacterial isolates: the viral load in the treated plants was only 0.4% vs. up to 74% in controls. This treatment consortium included P. aeruginosa S1HL3, Burkholderia sp. S1HL4 and Bacillus spp. isolates, JS2HR4 and JS3HR2. The principal-component biplot showed a highly significant correlation between the viral load percentage and the disease incidence.

Isolation of avian influenza virus (H9N2 from emu in china

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Kang Wenhua

2006-03-01

Full Text Available Abstract This is the first reported isolation of avian influenza virus (AIV from emu in China. An outbreak of AIV infection occurred at an emu farm that housed 40 four-month-old birds. Various degrees of haemorrhage were discovered in the tissues of affected emus. Cell degeneration and necrosis were observed microscopically. Electron microscopy revealed round or oval virions with a diameter of 80 nm to 120 nm, surrounded by an envelope with spikes. The virus was classified as low pathogenic AIV (LPAIV, according to OIE standards. It was named A/Emu/HeNen/14/2004(H9N2(Emu/HN/2004. The HA gene (1683bp was amplified by RT-PCR and it was compared with other animal H9N2 AIV sequences in GenBank, the US National Institutes of Health genetic sequence database. The results suggested that Emu/HN/2004 may have come from an avian influenza virus (H9N2 from Southern China.

Ageratum enation virus Infection Induces Programmed Cell Death and Alters Metabolite Biosynthesis in Papaver somniferum

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Ashish Srivastava

2017-07-01

Full Text Available A previously unknown disease which causes severe vein thickening and inward leaf curl was observed in a number of opium poppy (Papaver somniferum L. plants. The sequence analysis of full-length viral genome and associated betasatellite reveals the occurrence of Ageratum enation virus (AEV and Ageratum leaf curl betasatellite (ALCB, respectively. Co-infiltration of cloned agroinfectious DNAs of AEV and ALCB induces the leaf curl and vein thickening symptoms as were observed naturally. Infectivity assay confirmed this complex as the cause of disease and also satisfied the Koch’s postulates. Comprehensive microscopic analysis of infiltrated plants reveals severe structural anomalies in leaf and stem tissues represented by unorganized cell architecture and vascular bundles. Moreover, the characteristic blebs and membranous vesicles formed due to the virus-induced disintegration of the plasma membrane and intracellular organelles were also present. An accelerated nuclear DNA fragmentation was observed by Comet assay and confirmed by TUNEL and Hoechst dye staining assays suggesting virus-induced programmed cell death. Virus-infection altered the biosynthesis of several important metabolites. The biosynthesis potential of morphine, thebaine, codeine, and papaverine alkaloids reduced significantly in infected plants except for noscapine whose biosynthesis was comparatively enhanced. The expression analysis of corresponding alkaloid pathway genes by real time-PCR corroborated well with the results of HPLC analysis for alkaloid perturbations. The changes in the metabolite and alkaloid contents affect the commercial value of the poppy plants.

Two genotypes of H1N2 swine influenza viruses appeared among pigs in China.

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Xu, Chuantian; Zhu, Qiyun; Yang, Huanliang; Zhang, Xiumei; Qiao, Chuanling; Chen, Yan; Xin, Xiaoguang; Chen, Hualan

2009-10-01

H1N2 is one of the main subtypes of influenza, which circulates in swine all over the world. To investigate the prevalence and genetic of H1N2 in swine of China. Two H1N2 swine influenza viruses were isolated from Tianjin and Guangdong province of China in 2004 and 2006, respectively. The molecular evolution of eight gene segments was analyzed. A/Swine/Tianjin/1/2004 has low identity with A/Swine/Guangdong/2006; in the phylogenetic tree of PA gene, A/Swine/Guangdong/1/2006 and A/Swine/Guangxi/1/2006 along with the H1N2 swine isolates of North America formed a cluster; and A/Swine/Tianjin/2004 and A/Swine/Zhejiang/2004, along with the classical H1N1 swine isolates formed another cluster; except that NA gene of A/Swine/Tianjin/1/2004 fell into the cluster of the H3N2 human influenza virus, indicating the reassortment between H3N2 human and H1N1 swine influenza viruses. Two different genotypes of H1N2 appeared among pigs in China. A/swine/Guangdong/1/06 was probably from H1N2 swine influenza viruses of North America; while A/swine/Tianjin/1/04 maybe come from reassortments of classical H1N1 swine and H3N2 human viruses prevalent in North America.

Molecular evolution of hepatitis C virus in China: A nationwide study.

Science.gov (United States)

Huang, K; Chen, J; Xu, R; Jiang, X; Ma, X; Jia, M; Wang, M; Huang, J; Liao, Q; Shan, Z; Dailey, C; Song, X; Lu, L; Li, C; Rong, X; Zhang, M; Fu, Y

2018-03-01

The evolutionary and epidemic history and the regional differences of hepatitis C virus (HCV) are complex and remain unclear in the vast territory China. Here we recruited 1540 HCV-RNA positive patients sampled in 29 provinces across whole China, which is the largest sample capacity and the most comprehensive geographic coverage of China to our knowledge. 1b, 2a, 3b, 6a and 3a were the major subtypes in China. 1b was the most predominant subtype which presented in every province. The second most predominant subtype, 2a, appeared to concentrate in the north of China. Subtypes 3a and 3b were mainly found in the Southwest region, while 6a was restricted in the South region. We further estimated the origins of the dominating subtypes and discovered for the first time that a Chinese-specific transmission pattern for some strains of subtype 2a which was restricted in north China, and Chinese subtype 3b originated from Thailand. Copyright © 2018 Elsevier Inc. All rights reserved.

Epidemiology and vaccine of porcine epidemic diarrhea virus in China: a mini-review.

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Sun, Dongbo; Wang, Xinyu; Wei, Shan; Chen, Jianfei; Feng, Li

2016-03-01

Porcine epidemic diarrhea (PED) is an intestinal infectious disease caused by porcine epidemic diarrhea virus (PEDV); manifestations of the disease are diarrhea, vomiting and dehydration. Starting from the end of 2010, a PED outbreak occurred in several pig-producing provinces in southern China. Subsequently, the disease spread throughout the country and caused enormous economic losses to the pork industry. Accumulating studies demonstrated that new PEDV variants that appeared in China were responsible for the PED outbreak. In the current mini-review, we summarize PEDV epidemiology and vaccination in China.

Scales of North Atlantic wind stress curl determined from the comprehensive ocean-atmosphere data set

Science.gov (United States)

Ehret, Laura L.; O'Brien, James J.

1989-01-01

Nineteen years of wind data over the North Atlantic are used to calculate a field of wind stress curl. An empirical orthogonal function (EOF) analysis is performed on this field, resulting in spatial patterns of wind stress curl and associated time series. A Monte Carlo technique is used to establish the statistical significance of each spatial pattern, and the associated time series are spectrally analyzed. The first four statistically significant EOF modes represent more than 50 percent of the curl variance, and the spatial patterns of curl associated with these modes exhibit the major elements of North Atlantic climatology. Most of the time series spectral variance is contained in annual and semiannual frequencies. The features observed include the individual annual variation of the subtropical high and the subpolar low, the annual oscillation of intensity between pressure centers, the influence of localized strong SST gradients and associated cyclogenesis regions, and the constant nature of the trades.

Seed storage protein components are associated with curled ...

African Journals Online (AJOL)

PRECIOUS

2009-11-16

Nov 16, 2009 ... analysis suggests that the two increased protein spots in mutants were ... The main objective of this work was to gain further understanding of the influence of curled cotyledon on the seed storage protein components in soybean by com- .... cotyledon formation during Arabidopsis embryogenesis: interaction.

Novel triple reassortant H1N2 influenza viruses bearing six internal genes of the pandemic 2009/H1N1 influenza virus were detected in pigs in China.

Science.gov (United States)

Qiao, Chuanling; Liu, Liping; Yang, Huanliang; Chen, Yan; Xu, Huiyang; Chen, Hualan

2014-12-01

The pandemic A/H1N1 influenza viruses emerged in both Mexico and the United States in March 2009, and were transmitted efficiently in the human population. Transmissions of the pandemic 2009/H1N1 virus from humans to poultry and other species of mammals were reported from several continents during the course of the 2009 H1N1 pandemic. Reassortant H1N1, H1N2, and H3N2 viruses containing genes of the pandemic 2009/H1N1 viruses appeared in pigs in some countries. In winter of 2012, a total of 2600 nasal swabs were collected from healthy pigs in slaughterhouses located throughout 10 provinces in China. The isolated viruses were subjected to genetic and antigenic analysis. Two novel triple-reassortant H1N2 influenza viruses were isolated from swine in China in 2012, with the HA gene derived from Eurasian avian-like swine H1N1, the NA gene from North American swine H1N2, and the six internal genes from the pandemic 2009/H1N1 viruses. The two viruses had similar antigenic features and some significant changes in antigenic characteristics emerged when compared to the previously identified isolates. We inferred that the novel reassortant viruses in China may have arisen from the accumulation of the three types of influenza viruses, which further indicates that swine herds serve as "mixing vessels" for influenza viruses. Influenza virus reassortment is an ongoing process, and our findings highlight the urgent need for continued influenza surveillance among swine herds. Copyright © 2014 Elsevier B.V. All rights reserved.

Resistance to Wheat Curl Mite in Arthropod-Resistant Rye-Wheat Translocation Lines

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Lina Maria Aguirre-Rojas

2017-11-01

Full Text Available The wheat curl mite, Aceria toschiella (Keifer, and a complex of viruses vectored by A. toschiella substantially reduce wheat yields in every wheat-producing continent in the world. The development of A. toschiella-resistant wheat cultivars is a proven economically and ecologically viable method of controlling this pest. This study assessed A. toschiella resistance in wheat genotypes containing the H13, H21, H25, H26, H18 and Hdic genes for resistance to the Hessian fly, Mayetiola destructor (Say and in 94M370 wheat, which contains the Dn7 gene for resistance to the Russian wheat aphid, Diuraphis noxia (Kurdjumov. A. toschiella populations produced on plants containing Dn7 and H21 were significantly lower than those on plants of the susceptible control and no different than those on the resistant control. Dn7 resistance to D. noxia and H21 resistance to M. destructor resulted from translocations of chromatin from rye into wheat (H21—2BS/2RL, Dn7—1BL/1RS. These results provide new wheat pest management information, indicating that Dn7 and H21 constitute resources that can be used to reduce yield losses caused by A. toschiella, M. destructor, D. noxia, and wheat streak mosaic virus infection by transferring multi-pest resistance to single sources of germplasm.

Fatal H5N6 Avian Influenza Virus Infection in a Domestic Cat and Wild Birds in China.

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Yu, Zhijun; Gao, Xiaolong; Wang, Tiecheng; Li, Yanbing; Li, Yongcheng; Xu, Yu; Chu, Dong; Sun, Heting; Wu, Changjiang; Li, Shengnan; Wang, Haijun; Li, Yuanguo; Xia, Zhiping; Lin, Weishi; Qian, Jun; Chen, Hualan; Xia, Xianzhu; Gao, Yuwei

2015-06-02

H5N6 avian influenza viruses (AIVs) may pose a potential human risk as suggested by the first documented naturally-acquired human H5N6 virus infection in 2014. Here, we report the first cases of fatal H5N6 avian influenza virus (AIV) infection in a domestic cat and wild birds. These cases followed human H5N6 infections in China and preceded an H5N6 outbreak in chickens. The extensive migration routes of wild birds may contribute to the geographic spread of H5N6 AIVs and pose a risk to humans and susceptible domesticated animals, and the H5N6 AIVs may spread from southern China to northern China by wild birds. Additional surveillance is required to better understand the threat of zoonotic transmission of AIVs.

Molecular Evolution and Emergence of H5N6 Avian Influenza Virus in Central China.

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Du, Yingying; Chen, Mingyue; Yang, Jiayun; Jia, Yane; Han, Shufang; Holmes, Edward C; Cui, Jie

2017-06-15

H5N6 avian influenza virus (AIV) has posed a potential threat to public health since its emergence in China in 2013. To understand the evolution and emergence of H5N6 AIV in the avian population, we performed molecular surveillance of live poultry markets (LPMs) in Wugang Prefecture, Hunan Province, in central China, during 2014 and 2015. Wugang Prefecture is located on the Eastern Asian-Australian migratory bird flyway, and a human death due to an H5N6 virus was reported in the prefecture on 21 November 2016. In total, we sampled and sequenced the complete genomes of 175 H5N6 AIVs. Notably, our analysis revealed that H5N6 AIVs contain at least six genotypes arising from segment reassortment, including a rare variant that possesses an HA gene derived from H5N1 clade 2.3.2 and a novel NP gene that has its origins with H7N3 viruses. In addition, phylogenetic analysis revealed that genetically similar H5N6 AIVs tend to cluster according to their geographic regions of origin. These results help to reveal the evolutionary behavior of influenza viruses prior to their emergence in humans. IMPORTANCE The newly emerged H5N6 influenza A virus has caused more than 10 human deaths in China since 2013. In November 2016, a human death due to an H5N6 virus, in Wugang Prefecture, Hunan Province, was confirmed by the WHO. To better understand the evolution and emergence of H5N6 viruses, we surveyed live poultry markets (LPMs) in Wugang Prefecture before the reported human death, with a focus on revealing the diversity and genomic origins of H5N6 in birds during 2014 and 2015. In general, H5N6 viruses in this region were most closely related to H5N1 clade 2.3.4.4, with the exception of one virus with an HA gene derived from clade 2.3.2 such that it represents a novel reassortant. Clearly, the ongoing surveillance of LPMs is central to monitoring the emergence of pathogenic influenza viruses. Copyright © 2017 American Society for Microbiology.

Complete genome sequence of a divergent strain of lettuce chlorosis virus from Periwinkle in China

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A novel strain of Lettuce chlorosis virus (LCV) was identified from periwinkle in China (PW) with foliar interveinal chlorosis and plant dwarfing. Complete nucleotide (nt) sequences of genomic RNA1 and RNA2 of the virus are 8,602 nt and 8,456 nt, respectively. The genomic organization of LCV-PW rese...

Reliability of Arm Curl and Chair Stand tests for assessing muscular endurance in older people

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Boneth M

2012-05-01

Full Text Available Objective: to assess the test-retest reliability and level of agreement between measures of the 30 second (30-s Arm Curl and 30-s Chair Stand test in a sample of older adults from Bucaramanga. Materials and methods: a study of evaluation of diagnostic technology was done. Both tests were administered by the same evaluator to 111 adults older than 59 year-old (70,4 ± 7,3, on two occasions, with an interval of time between measures of 4 to 8 days. In the analysis, test-retest reliability was determined using the Intraclass Correlation Coefficient ICC= 2,1 with their confidence interval 95% (CI 95% respective. The agreement level was established by the Bland and Altman method. Results: the test-retest reproducibility of the 30-s Arm Curl test was very good ICC= 0,88 and to the Chair Stand test was good ICC= 0,78. The agreement was very good for both tests of muscle endurance. The CI 95% were between -3,8 and 3,2 stands to 30-s Chair Stand test and between -3,1 and 2,8 curls to 30-s Arm Curl test. Conclusion: the 30-s Arm Curl and 30-s Chair Stand test have good reliability and agreement to assess muscle endurance in older adults functionally independent.

Characterization of a novel curled-cotyledons mutant in soybean ...

African Journals Online (AJOL)

ARL

different stages. Protein and amino acid contents in seeds of mutant are higher than those of the wild .... curled shape, from seedling to maturation phase (Figure. 1D-1F). ..... Arabidopsis seed dermination by stimulating abscisic acid synthesis.

Isolation and sequence analysis of a canine distemper virus from a raccoon dog in Jilin Province, China.

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Cheng, Yuening; Wang, Jianke; Zhang, Miao; Zhao, Jianjun; Shao, Xiqun; Ma, Zengjun; Zhao, Hang; Lin, Peng; Wu, Hua

2015-10-01

Canine distemper virus (CDV) is a major pathogen not only in raccoon dogs but also in a variety of carnivorous animals, including domesticated animals, particularly if they have not been vaccinated. In this study, a wild-type strain of CDV was isolated from lung tissue from a raccoon dog kept at a fur farm in Jilin Province, China. Cytopathic effects typical of CDV infection were observed after three blind passages in Vero cells, yielding a virus titer of 10(4.6) TCID50/mL. Virus identification was carried out by RT-PCR, immunofluorescence, electron microscopy, and genome sequencing. The results showed that the isolated virus, termed the SY strain, corresponded to the Asia-1 genotype of CDV and has a genome of 15,690 nucleotides. This represents the first complete nucleotide sequence of a CDV strain circulating in raccoon dogs in China.

A new genus and species of Macrosiphini (Hemiptera, Aphididae from China, living on Isodon eriocalyx

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Bin Zhang

2013-12-01

Full Text Available The aphid genus Nigritergaphis gen. n. is described, and N. crassisetosa sp.n. on Isodon eriocalyx (Dunn Kudô (Lamiaceae from Yunnan, China is described and illustrated. The new species curls and distorts the leaves of this important traditional Chinese medicinal plant, and is evidently specific to this host. Holotype and paratypes are deposited in the National Zoological Museum of China, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.

A fatal yellow fever virus infection in China: description and lessons

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Chen, Zhihai; Liu, Lin; Lv, Yanning; Zhang, Wei; Li, Jiandong; Zhang, Yi; Di, Tian; Zhang, Shuo; Liu, Jingyuan; Li, Jie; Qu, Jing; Hua, Wenhao; Li, Chuan; Wang, Peng; Zhang, Quanfu; Xu, Yanli; Jiang, Rongmeng; Wang, Qin; Chen, Lijuan; Wang, Shiwen; Pang, Xinghuo; Liang, Mifang; Ma, Xuejun; Li, Xingwang; Wang, Quanyi; Zhang, Fujie; Li, Dexin

2016-01-01

Yellow fever (YF) is a viral disease endemic to the tropical regions of Africa and South America. An outbreak of YF has been occurring in Angola, since the beginning of 2016. In March 2016, a 32-year-old Chinese man who returned from Angola was hospitalized and diagnosed with the first case of imported YF in China. Clinical observations, blood viral RNA detection, serological testing and treatments for the patient were performed daily. The virus was isolated in Vero cells, and the complete viral genome was sequenced and analyzed using the next-generation genomic sequencing platform. The patient presented with hemorrhagic fever, jaundice and oliguria at day 3 after onset, which rapidly progressed to multisystem organ failure with extremely elevated liver, pancreatic and myocardial enzymes. The patient died despite the intensive supportive treatments that were performed. A liver biopsy showed severe and multilobular necrosis. Viral RNA was detectable throughout the clinical course of the disease. Whole-genomic sequence analysis revealed that the virus belongs to the Angola71 genotype. Although the virus has been circulating in Angola for 45 years, only 14 amino-acid substitutions and no amino-acid changes were observed in the membrane and envelope proteins compared with the virus collected in 1971. The presence of this imported YF case in China indicated that with the increase in business travel among countries, YF outbreaks in Africa can lead to the international spread of the disease. The production and use of YF vaccines is, therefore, an urgent issue. PMID:27406389

Qualitative investigation into students' use of divergence and curl in electromagnetism

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Bollen, Laurens; van Kampen, Paul; Baily, Charles; De Cock, Mieke

2016-12-01

Many students struggle with the use of mathematics in physics courses. Although typically well trained in rote mathematical calculation, they often lack the ability to apply their acquired skills to physical contexts. Such student difficulties are particularly apparent in undergraduate electrodynamics, which relies heavily on the use of vector calculus. To gain insight into student reasoning when solving problems involving divergence and curl, we conducted eight semistructured individual student interviews. During these interviews, students discussed the divergence and curl of electromagnetic fields using graphical representations, mathematical calculations, and the differential form of Maxwell's equations. We observed that while many students attempt to clarify the problem by making a sketch of the electromagnetic field, they struggle to interpret graphical representations of vector fields in terms of divergence and curl. In addition, some students confuse the characteristics of field line diagrams and field vector plots. By interpreting our results within the conceptual blending framework, we show how a lack of conceptual understanding of the vector operators and difficulties with graphical representations can account for an improper understanding of Maxwell's equations in differential form. Consequently, specific learning materials based on a multiple representation approach are required to clarify Maxwell's equations.

Isolation and genetic characterization of avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China.

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Yu, Hai; Zhang, Peng-Chao; Zhou, Yan-Jun; Li, Guo-Xin; Pan, Jie; Yan, Li-Ping; Shi, Xiao-Xiao; Liu, Hui-Li; Tong, Guang-Zhi

2009-08-21

As pigs are susceptible to both human and avian influenza viruses, they have been proposed to be intermediate hosts or mixing vessels for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we reported avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Homology and phylogenetic analyses showed that the H1N1 virus (A/swine/Zhejiang/1/07) was closely to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses, which was for the first time reported in China; and the two H1N2 viruses (A/swine/Shanghai/1/07 and A/swine/Guangxi/13/06) were novel ressortant H1N2 influenza viruses containing genes from the classical swine (HA, NP, M and NS), human (NA and PB1) and avian (PB2 and PA) lineages, which indicted that the reassortment among human, avian, and swine influenza viruses had taken place in pigs in China and resulted in the generation of new viruses. The isolation of avian-like H1N1 influenza virus originated from the European swine H1N1 viruses, especially the emergence of two novel ressortant H1N2 influenza viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and swine influenza virus surveillance in China should be given a high priority.

[Epidemiology of human infection with avian influenza A(H7N9) virus in China, 2013-2017].

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Han, D D; Han, C X; Li, L Y; Wang, M; Yang, J H; Li, M

2018-01-10

Objective: To understand the epidemiological characteristics of human infection with avian influenza A (H7N9) virus in China, and provide evidence for the prevention and control of human infection with H7N9 virus. Methods: The published incidence data of human infection with H7N9 virus in China from March 2013 to April 2017 were collected. Excel 2007 software was used to perform the analysis. The characteristics of distribution of the disease, exposure history, cluster of the disease were described. Results: By the end of April 2017, a total of 1 416 cases of human infection with H7N9 virus were confirmed in China, including 559 deaths, the case fatality rate was 39.5%. In 2016, the case number was lowest (127 cases), with the highest fatality rate (57.5%). The first three provinces with high case numbers were Zhejiang, Guangdong and Jiangsu. The median age of the cases was 55 years and the male to female ratio was 2.3∶1. Up to 66% of cases had clear live poultry exposure history before illness onset, 31% of cases had unknown exposure history and only 3% of the cases had no live poultry exposure history. There were 35 household clusters (5 in 2013, 9 in 2014, 6 in 2015, 5 in 2016, 10 in 2017), which involved 72 cases, accounting for 5% of the total cases. Conclusions: The epidemic of human infection with H7N9 virus in China during 2013-2017 had obvious seasonality and spatial distribution. There was limited family clustering. Infection cases were mostly related to poultry contact.

Injuries in recreational curling include head injuries and may be prevented by using proper footwear.

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Ting, D K; Brison, R J

2015-04-01

Our study examines a recreational curling population to describe patterns of injury occurrence, estimate risk of injury and to gauge attitudes towards equipment-based prevention strategies. In a retrospective case series, we queried the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP), a national injury surveillance database, for curling injuries entered between 1993 and 2011. Kingston General Hospital and Hotel Dieu Hospital provide the two Kingston, Ontario, sites for emergency department (ED) care and participate in CHIRPP. Each retrieved entry underwent a chart review. A secondary survey was mailed to select individuals who had experienced curling injuries to solicit details on their injury and attitudes towards equipment to prevent injury. We used descriptive statistics for rates and proportions. Over 90% of acute curling injuries resulted from a fall, and 31.7% were head impacts. We found that acute injuries requiring ED presentation occur at a rate of approximately 0.17 per 1000 athlete-exposures (95% CI: 0.12-0.22). The secondary survey was completed by 54% of potential respondents. Of survey respondents, 41.3% attributed their fall to a lack of proper footwear and 73.5% of respondents agreed with mandatory sport-specific footwear as a prevention strategy, but only 8% agreed with mandatory helmet wear. Although curling injuries requiring medical care are not common, head injuries make up a large proportion. Mandated use of appropriate footwear appears to be the most effective prevention strategy, as well as the measure deemed most acceptable by players.

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum).

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Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

2017-01-01

Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways.

SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum.

Directory of Open Access Journals (Sweden)

Yunzhou Li

Full Text Available Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3 in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L. infected with tomato yellow leaf curl virus (TYLCV. There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA and jasmonic acid (JA defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD, peroxidase (POD, catalase (CAT, and ascorbate peroxidase (APX activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways.

Predicting hand function in older adults: evaluations of grip strength, arm curl strength, and manual dexterity.

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Liu, Chiung-Ju; Marie, Deana; Fredrick, Aaron; Bertram, Jessica; Utley, Kristen; Fess, Elaine Ewing

2017-08-01

Hand function is critical for independence in activities of daily living for older adults. The purpose of this study was to examine how grip strength, arm curl strength, and manual dexterous coordination contributed to time-based versus self-report assessment of hand function in community-dwelling older adults. Adults aged ≥60 years without low vision or neurological disorders were recruited. Purdue Pegboard Test, Jamar hand dynamometer, 30-second arm curl test, Jebsen-Taylor Hand Function Test, and the Late-Life Function and Disability Instrument were administered to assess manual dexterous coordination, grip strength, arm curl strength, time-based hand function, and self-report of hand function, respectively. Eighty-four adults (mean age = 72 years) completed the study. Hierarchical multiple regressions show that older adults with better arm curl strength (β = -.25, p function test. In comparison, older adults with better grip strength (β = .40, p function. The relationship between grip strength and hand function may be test-specific. Grip strength becomes a significant factor when the test requires grip strength to successfully complete the test tasks. Arm curl strength independently contributed to hand function in both time-based and self-report assessments, indicating that strength of extrinsic muscles of the hand are essential for hand function.

Computation of Surface Integrals of Curl Vector Fields

Science.gov (United States)

Hu, Chenglie

2007-01-01

This article presents a way of computing a surface integral when the vector field of the integrand is a curl field. Presented in some advanced calculus textbooks such as [1], the technique, as the author experienced, is simple and applicable. The computation is based on Stokes' theorem in 3-space calculus, and thus provides not only a means to…

Effect of morphological fin curl on the swimming performance and station-holding ability of juvenile shovelnose sturgeon

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Deslauriers, David; Johnston, Ryan; Chipps, Steven R.

2016-01-01

We assessed the effect of fin-curl on the swimming and station-holding ability of juvenile shovelnose sturgeon Scaphirhynchus platorynchus (mean fork length = 17 cm; mean weight = 16 g; n = 21) using a critical swimming speed test performed in a small swim chamber (90 L) at 20°C. We quantified fin-curl severity using the pectoral fin index. Results showed a positive relationship between pectoral fin index and critical swimming speed indicative of reduced swimming performance displayed by fish afflicted with a pectoral fin index < 8%. Fin-curl severity, however, did not affect the station-holding ability of individual fish. Rather, fish affected with severe fin-curl were likely unable to use their pectoral fins to position their body adequately in the water column, which led to the early onset of fatigue. Results generated from this study should serve as an important consideration for future stocking practices.

Human Infection with Highly Pathogenic Avian Influenza A(H7N9) Virus, China.

Science.gov (United States)

Ke, Changwen; Mok, Chris Ka Pun; Zhu, Wenfei; Zhou, Haibo; He, Jianfeng; Guan, Wenda; Wu, Jie; Song, Wenjun; Wang, Dayan; Liu, Jiexiong; Lin, Qinhan; Chu, Daniel Ka Wing; Yang, Lei; Zhong, Nanshan; Yang, Zifeng; Shu, Yuelong; Peiris, Joseph Sriyal Malik

2017-07-01

The recent increase in zoonotic avian influenza A(H7N9) disease in China is a cause of public health concern. Most of the A(H7N9) viruses previously reported have been of low pathogenicity. We report the fatal case of a patient in China who was infected with an A(H7N9) virus having a polybasic amino acid sequence at its hemagglutinin cleavage site (PEVPKRKRTAR/GL), a sequence suggestive of high pathogenicity in birds. Its neuraminidase also had R292K, an amino acid change known to be associated with neuraminidase inhibitor resistance. Both of these molecular features might have contributed to the patient's adverse clinical outcome. The patient had a history of exposure to sick and dying poultry, and his close contacts had no evidence of A(H7N9) disease, suggesting human-to-human transmission did not occur. Enhanced surveillance is needed to determine whether this highly pathogenic avian influenza A(H7N9) virus will continue to spread.

First report of zucchini tigre mosaic virus infecting several cucurbit plants in China

Science.gov (United States)

Pumpkin (Cucurbita moschata Duch.), Cucumber (Cucumis sativus Linn.) and Zucchini (Cucurbita pepo Linn.) are important crops in tropical and subtropical regions in the world, and they are popular vegetable crops in China. There are currently 59 viruses known infecting cucurbit plants which including...

Antibodies against severe fever with Thrombocytopenia syndrome Virus in healthy persons, China, 2013

NARCIS (Netherlands)

Zhang Lei, Lei; Sun, J.; Yan, J.; Huakun, L.; Chai, C.Y.; Sun, Y.; Shao, B.; Jiang, J.D.; Chen, Z.; Kortekaas, J.A.; Zhang, Y.

2014-01-01

In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding

Injuries in recreational curling include head injuries and may be prevented by using proper footwear

Directory of Open Access Journals (Sweden)

D. K. Ting

2015-04-01

Full Text Available Introduction: Our study examines a recreational curling population to describe patterns of injury occurrence, estimate risk of injury and to gauge attitudes towards equipment-based prevention strategies. Methods: In a retrospective case series, we queried the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP, a national injury surveillance database, for curling injuries entered between 1993 and 2011. Kingston General Hospital and Hotel Dieu Hospital provide the two Kingston, Ontario, sites for emergency department (ED care and participate in CHIRPP. Each retrieved entry underwent a chart review. A secondary survey was mailed to select individuals who had experienced curling injuries to solicit details on their injury and attitudes towards equipment to prevent injury. We used descriptive statistics for rates and proportions. Results: Over 90% of acute curling injuries resulted from a fall, and 31.7% were head impacts. We found that acute injuries requiring ED presentation occur at a rate of approximately 0.17 per 1000 athlete-exposures (95% CI: 0.12–0.22. The secondary survey was completed by 54% of potential respondents. Of survey respondents, 41.3% attributed their fall to a lack of proper footwear and 73.5% of respondents agreed with mandatory sport-specific footwear as a prevention strategy, but only 8% agreed with mandatory helmet wear. Conclusions: Although curling injuries requiring medical care are not common, head injuries make up a large proportion. Mandated use of appropriate footwear appears to be the most effective prevention strategy, as well as the measure deemed most acceptable by players.

A Scott bench with ergonomic thorax stabilisation pad improves body posture during preacher arm curl exercise.

Science.gov (United States)

Biscarini, Andrea; Benvenuti, Paolo; Busti, Daniele; Zanuso, Silvano

2016-05-01

We assessed whether the use of an ergonomic thorax stabilisation pad, during the preacher arm curl exercise, could significantly reduce the excessive shoulder protraction and thoracic kyphosis induced by the standard flat pad built into the existing preacher arm curl equipment. A 3D motion capture system and inclinometers were used to measure shoulder protraction and thoracic kyphosis in 15 subjects performing preacher arm curl with a plate-loaded machine provided with the standard flat pad. The same measures were repeated after replacing the flat pad with a new ergonomic pad, specifically designed to accommodate the thorax profile and improve body posture. Pad replacement significantly (p ergonomic pad may potentially allow a more effective training, prevent musculoskeletal discomfort and reduce the risk of injury. Practitioner summary: We have designed an ergonomic thorax stabilisation pad for the preacher arm curl exercise. The new ergonomic pad improves the poor posture conditions induced by the standard flat pad and may potentially allow a more effective training, prevent musculoskeletal discomfort, improve the breathing function and reduce the risk of injury.

Thermal and curl properties of PET/PP blend fibers compatibilized ...

Indian Academy of Sciences (India)

67

blend fibers were prepared using a melt-spinning system, and their curl properties were investigated. ... by extrusion and injection molding processes. ..... Inuwa I M, Hassan A, Samsudin S A, Kassim M H M and Jawaid M 2014. Polym.

Spectral mimetic least-squares method for div-curl systems

NARCIS (Netherlands)

Gerritsma, Marc; Palha, Artur; Lirkov, I.; Margenov, S.

2018-01-01

In this paper the spectral mimetic least-squares method is applied to a two-dimensional div-curl system. A test problem is solved on orthogonal and curvilinear meshes and both h- and p-convergence results are presented. The resulting solutions will be pointwise divergence-free for these test

The first human infection with severe fever with thrombocytopenia syndrome virus in Shaanxi Province, China

Directory of Open Access Journals (Sweden)

Jing Wei

2015-06-01

Conclusions: SFTSV readily infects humans with outdoor exposure. The results of the serological study indicate that the virus circulates widely in Shaanxi Province. SFTSV represents a public health threat in China.

Molecular characterization of a divergent strain of calla lily chlorotic spot virus infecting celtuce (Lactuca sativa var. augustana) in China.

Science.gov (United States)

Wu, Xiaodong; Wu, Xiaoyun; Li, Wenbin; Cheng, Xiaofei

2018-05-01

Through sequencing and assembly of small RNAs, an orthotospovirus was identified from a celtuce plant (Lactuca sativa var. augustana) showing vein clearing and chlorotic spots in the Zhejiang province of China. The S, M, and L RNAs of this orthotospovirus were determined to be 3146, 4734, and 8934 nt, respectively, and shared 30.4-72.5%, 43.4-80.8%, and 29.84-82.9% nucleotide sequence identities with that of known orthotospoviruses. The full length nucleoprotein (N) of this orthotospovirus shared highest amino acid sequence identity (90.25%) with that of calla lily chlorotic spot virus isolated from calla lily (CCSV-calla) [China: Taiwan: 2001] and tobacco (CCSV-LJ1) [China: Lijiang: 2014]. Phylogenetic analyses showed that this orthotospovirus is phylogenetically associated with CCSV isolates and clustered with CCSV, tomato zonate spot virus (TZSV), and tomato necrotic spot-associated virus (TNSaV) in a separate sub-branch. These results suggest that this orthotospovirus is a divergent isolate of CCSV and was thus named CCSV-Cel [China: Zhejiang: 2017].

Injuries in recreational curling include head injuries and may be prevented by using proper footwear

OpenAIRE

D. K. Ting; R. J. Brison

2015-01-01

Introduction: Our study examines a recreational curling population to describe patterns of injury occurrence, estimate risk of injury and to gauge attitudes towards equipment-based prevention strategies. Methods: In a retrospective case series, we queried the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP), a national injury surveillance database, for curling injuries entered between 1993 and 2011. Kingston General Hospital and Hotel Dieu Hospital provide the two Kingston,...

Short communication: isolation and phylogenetic analysis of an avian-origin H3N2 canine influenza virus in dog shelter, China.

Science.gov (United States)

Su, Shuo; Yuan, Ziguo; Chen, Jidang; Xie, Jiexiong; Li, Huatao; Huang, Zhen; Zhang, Minze; Du, Guohao; Chen, Zhongming; Tu, Liqing; Zou, Yufei; Miao, Junhao; Wang, Hui; Jia, Kun; Li, Shoujun

2013-06-01

A H3N2 canine influenza virus, A/canine/Guangdong/3/2011 (H3N2), was isolated from roaming dogs in rural China. Sequence and phylogenetic analysis of eight gene segments revealed that the A/canine/Guangdong/3/2011 (H3N2) was most similar to a recent H3N2 canine influenza virus isolated in cats from South Korea, which originated from an avian strain. To our knowledge, this is the first report of an avian-origin H3N2 CIV which was isolated from roaming dogs in China. The epidemiologic information provided herein suggests that continued study is required to determine if this virus could be established in the roaming dog population in rural China and pose potential threats to public health.

Role of Poultry in the Spread of Novel H7N9 Influenza Virus in China

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Pantin-Jackwood, Mary J.; Miller, Patti J.; Spackman, Erica; Swayne, David E.; Susta, Leonardo; Costa-Hurtado, Mar

2014-01-01

ABSTRACT The recent outbreak of H7N9 influenza in China has resulted in many human cases with a high fatality rate. Poultry are the likely source of infection for humans on the basis of sequence analysis and virus isolations from live bird markets, but it is not clear which species of birds are most likely to be infected and shedding levels of virus sufficient to infect humans. Intranasal inoculation of chickens, Japanese quail, pigeons, Pekin ducks, Mallard ducks, Muscovy ducks, and Embden geese with 106 50% egg infective doses of the A/Anhui/1/2013 virus resulted in infection but no clinical disease signs. Virus shedding was much higher and prolonged in quail and chickens than in the other species. Quail effectively transmitted the virus to direct contacts, but pigeons and Pekin ducks did not. In all species, virus was detected at much higher titers from oropharyngeal swabs than cloacal swabs. The hemagglutinin gene from samples collected from selected experimentally infected birds was sequenced, and three amino acid differences were commonly observed when the sequence was compared to the sequence of A/Anhui/1/2013: N123D, N149D, and L217Q. Leucine at position 217 is highly conserved for human isolates and is associated with α2,6-sialic acid binding. Different amino acid combinations were observed, suggesting that the inoculum had viral subpopulations that were selected after passage in birds. These experimental studies corroborate the finding that certain poultry species are reservoirs of the H7N9 influenza virus and that the virus is highly tropic for the upper respiratory tract, so testing of bird species should preferentially be conducted with oropharyngeal swabs for the best sensitivity. IMPORTANCE The recent outbreak of H7N9 influenza in China has resulted in a number of human infections with a high case fatality rate. The source of the viral outbreak is suspected to be poultry, but definitive data on the source of the infection are not available. This

Edge curling that has plagued scrolls for millenniums

Science.gov (United States)

Chou, Ming-Han; Shen, Wei-Chao; Wang, Yi-Ping; Hung, Sun-Hsin; Hong, Tzay-Ming; Department of Registration and Conservation, National Palace Museum Collaboration; Department of Physics, National Tsing Hua University Team

2014-03-01

Qi-Wa refers to the up curl on the lengths of handscrolls and hanging scrolls, which has troubled Chinese artisans and emperors for as long as the art of painting and calligraphy exists. This warp is unwelcome not only for aesthetic reasons, but its potential damage to the fiber and ink. Although it is generally treated as a part of the cockling and curling due to moisture, consistency of paste, and defects from the mounting procedures, we demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing Qi-Wa. In contrast to the former factors whose effects are less predictable, the plastic deformation and strain distribution on a membrane are a well-defined mechanical problem. We study this phenomenon by experiments, theoretical models, and Molecular Dynamics Simulation, and obtain consistent scaling relations for the Qi-Wa height. This knowledge enables us to propose modifications on the traditional mounting techniques, that are tested on real mounted paper to be effective at mitigating Qi-Wa. By experimenting on polymer-based films, we demonstrate possible relevance of our study to the modern development of flexible electronic paper.

Effect of Performance Speed on Trunk Movement Control During the Curl-Up Exercise

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Barbado David

2015-06-01

Full Text Available Trunk exercise speed has significant effects on neuro-mechanical demands; however, the influence of a variety of exercise speeds on motor control of the trunk displacement remains unknown. The aim of this study was to assess the effect of performance speed on trunk motion control during the curl-up exercise by analyzing the kinematic variance about the sagittal trajectory. Seventeen subjects volunteered to perform curl-ups at different cadences controlled by a metronome. Standard deviation (SD and range (RG of shoulder girdle medial-lateral displacement (SGML and detrended fluctuation analysis (DFA of SGML were calculated to examine linear variability and long range autocorrelation of medial-lateral upper trunk displacements, respectively. In addition, SD, RG and DFA of centre of pressure medial-lateral displacement (COPML were performed to analyze the behavior of the motor system while controlling trunk displacement. Although SD and RG of COPML increased as speed increased, the curl-up cadence did not have significant effects on SD and RG of SGML. These results suggest that although high speed curl-ups challenged participants’ ability to carry out medial-lateral adjustments, an increase of performance speed did not modify the linear variability about the sagittal trajectory. Regarding DFA, the scaling exponent α of SGML and COPML was higher for the fastest movements, mainly in long term fluctuations. Therefore, to maintain the target trajectory, participants used different strategies depending on performance speed. This is to say, there were less trajectory changes when participants performed the fastest exercises.

Characterisation of a highly pathogenic H5N1 clade 2.3.2 influenza virus isolated from swans in Shanghai, China.

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Zhao, Guo; Zhong, Lei; Lu, Xinlun; Hu, Jiao; Gu, Xiaobing; Kai, Yan; Song, Qingqing; Sun, Qing; Liu, Jinbao; Peng, Daxin; Wang, Xiaoquan; Liu, Xiaowen; Liu, Xiufan

2012-02-01

In spring 2009, one strain of H5N1 clade 2.3.2 virus was isolated from wild swans in Shanghai, indicating the importance of the wild swan in the ecology of this highly pathogenic avian influenza virus (HPAIV) in Eastern China. Pathogenicity experiments conducted in this study indicated that the virus was highly pathogenic for chickens but lowly pathogenic for mammalian hosts, as evidenced by reduced infection of mice. The analysis of complete genome sequences and genetic evolution showed that A/Swan/Shanghai/10/09 (SW/SH/09) may be derived from the strain A/silky chicken/Shantou/475/2004 (CK/ST/04), which is homologous to the influenza viruses isolated from chicken, duck, pika, little egret, swan, mandarin duck and bar-headed goose in China Hunan, China Qinghai, Mongolia, Russia, Japan, Korea, Laos and Hong Kong during 2007-2011, indicating that the virus has retro-infected diverse wild birds from chicken, and significant spread of the virus is still ongoing through overlapping migratory flyways. On the basis of the molecular analysis, we also found that there was a deletion of the glycosylation site (NSS) in amino acid 156 of the hemagglutinin (HA) protein when compared with that of the other Clade 2.3.2 viruses isolated between 2007 and 2011. More importantly, the sequence analysis of SW/SH/09 virus displayed the drug-resistant mutations on the matrix protein (M2) and neuraminidase (NA) genes.

Isolation and molecular characterization of an H5N1 swine influenza virus in China in 2015.

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Wu, Haibo; Yang, Fan; Lu, Rufeng; Xu, Lihua; Liu, Fumin; Peng, Xiuming; Wu, Nanping

2018-03-01

In 2015, an H5N1 influenza virus was isolated from a pig in Zhejiang Province, Eastern China. This strain was characterized by whole-genome sequencing with subsequent phylogenetic analysis. Phylogenetic analysis showed that all segments from this strain belonged to clade 2.3.2 and that it had received its genes from poultry influenza viruses in China. A Glu627Lys mutation associated with pathogenicity was observed in the PB2 protein. This strain was moderately pathogenic in mice and was able to replicate without prior adaptation. These results suggest that active surveillance of swine influenza should be used as an early warning system for influenza outbreaks in mammals.

Rubella epidemic caused by genotype 1E rubella viruses in Beijing, China, in 2007-2011.

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Chen, Meng; Zhu, Zhen; Liu, Donglei; Huang, Guohong; Huang, Fang; Wu, Jiang; Zhang, Tiegang; Xu, Wenbo; Pang, Xinghuo

2013-04-18

A series of different rubella vaccination strategies were implemented to control rubella and prevent congenital rubella virus infection in Beijing, China. The rubella vaccine was available in 1995 in Beijing, and was introduced into the Beijing immunization program (vaccine recipients at their own expense vaccination) in 2000, and was introduced into the National Expanded Program on Immunization (vaccine recipients free vaccination) in 2006. Rubella virological surveillance started in Beijing in 2007. The reported rubella incidence rate has decreased dramatically due to the introduction of the vaccine in Beijing since 1995. However, rubella epidemics occurred regardless in 2001 and 2007. The incidence rate among the floating population has gradually increased since 2002, reaching 2 or more times that in the permanent resident population. The peak age of rubella cases gradually changed from tree was constructed based on the World Health Organization standard sequence window for rubella virus isolates. All Beijing rubella virus isolates belong to genotype 1E/cluster1 and were clustered interspersed with viruses from other provinces in China. The effective number of infections indicated by a Bayesian skyline plot remained constant from 2007 to 2011. The proportion of rubella cases among the floating population has increased significantly in Beijing since 2002, and the disease burden gradually shifted to the older age group (15- to 39-year olds), which has become a major group with rubella infection since 2006. Genotype 1E rubella virus continuously caused a rubella epidemic in Beijing in 2007-2011 and was the predominant virus, and all Beijing genotype 1E viruses belong to cluster 1, which is also widely circulated throughout the country.

Cross-border spread, lineage displacement and evolutionary rate estimation of rabies virus in Yunnan Province, China.

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Zhang, Yuzhen; Vrancken, Bram; Feng, Yun; Dellicour, Simon; Yang, Qiqi; Yang, Weihong; Zhang, Yunzhi; Dong, Lu; Pybus, Oliver G; Zhang, Hailin; Tian, Huaiyu

2017-06-03

Rabies is an important but underestimated threat to public health, with most cases reported in Asia. Since 2000, a new epidemic wave of rabies has emerged in Yunnan Province, southwestern China, which borders three countries in Southeast Asia. We estimated gene-specific evolutionary rates for rabies virus using available data in GenBank, then used this information to calibrate the timescale of rabies virus (RABV) spread in Asia. We used 452 publicly available geo-referenced complete nucleoprotein (N) gene sequences, including 52 RABV sequences that were recently generated from samples collected in Yunnan between 2008 and 2012. The RABV N gene evolutionary rate was estimated to be 1.88 × 10 -4 (1.37-2.41 × 10 -4 , 95% Bayesian credible interval, BCI) substitutions per site per year. Phylogenetic reconstructions show that the currently circulating RABV lineages in Yunnan result from at least seven independent introductions (95% BCI: 6-9 introductions) and represent each of the three main Asian RABV lineages, SEA-1, -2 and -3. We find that Yunnan is a sink location for the domestic spread of RABV and connects RABV epidemics in North China, South China, and Southeast Asia. Cross-border spread from southeast Asia (SEA) into South China, and intermixing of the North and South China epidemics is also well supported. The influx of RABV into Yunnan from SEA was not well-supported, likely due to the poor sampling of SEA RABV diversity. We found evidence for a lineage displacement of the Yunnan SEA-2 and -3 lineages by Yunnan SEA-1 strains, and considered whether this could be attributed to fitness differences. Overall, our study contributes to a better understanding of the spread of RABV that could facilitate future rabies virus control and prevention efforts.

Method of inhibiting plant virus pathogen infections by crispr/cas9-mediated interference

KAUST Repository

Mahfouz, Magdy Mahmoud

2016-11-24

A genetically modified tobacco plant or tomato plant resistant to at least one pathogenic geminiviridae virus species is provided. The plant comprises a heterologous CRISPR/Cas9 system and at least one heterologous nucleotide sequence that is capable of hybridizing to a nucleotide sequence of the pathogenic virus and that directs inactivation of the pathogenic virus species or plurality of viral species by the CRISPR/Cas9 system. The heterologous nucleotide sequence can be complementary to, but not limited to an Intergenic Region (IR) of the Tomato Yellow Leaf Curl Virus (TYLCV), Further provided are methods of generating a genetically modified plant that is resistant to a virus pathogen by a heterologous CRISPR/Cas9 system and expression of a gRNA specifically targeting the virus.

H5N1 avian influenza virus: human cases reported in southern China.

NARCIS (Netherlands)

Crofts, J.; Paget, J.; Karcher, F.

2003-01-01

Two cases of confirmed influenza due to the avian influenza A H5N1 virus were reported last week in Hong Kong (1). The cases occurred in a Hong Kong family who had recently visited Fujian province in southern China. The daughter, aged 8 years, died following a respiratory illness. The cause of her

Molecular and Biochemical Characterization of Cotton Epicuticular Wax in Defense Against Cotton Leaf Curl Disease.

Science.gov (United States)

Khan, Muhammad Azmat Ullah; Shahid, Ahmad Ali; Rao, Abdul Qayyum; Bajwa, Kamran Shehzad; Samiullah, Tahir Rehman; Muzaffar, Adnan; Nasir, Idrees Ahmad; Husnain, Tayyab

2015-12-01

Gossypium arboreumis resistant to Cotton leaf curl Burewala virus and its cognate Cotton leaf curl Multan beta satellite ( CLCuBuV and CLCuMB ). However, the G. arboreum wax deficient mutant (GaWM3) is susceptible to CLCuV . Therefore, epicuticular wax was characterized both quantitatively and qualitatively for its role as physical barrier against whitefly mediated viral transmission and co-related with the titer of each viral component (DNA-A, alphasatellite and betasatellite) in plants. The hypothesis was the CLCuV titer in cotton is dependent on the amount of wax laid down on plant surface and the wax composition. Analysis of the presence of viral genes, namely alphasatellite, betasatellite and DNA-A, via real-time PCR in cotton species indicated that these genes are detectable in G. hirsutum , G. harknessii and GaWM3, whereas no particle was detected in G. arboreum . Quantitative wax analysis revealed that G. arboreum contained 183 μg.cm -2 as compared to GaWM3 with only 95 μg.cm -2 . G. hirsutum and G. harknessii had 130 μg.cm -2 and 146 μg.cm -2 , respectively. The GCMS results depicted that Lanceol, cis was 45% in G. harknessii . Heptadecanoic acid was dominant in G. arboreum with 25.6%. GaWM3 had 18% 1,2,-Benenedicarboxylic acid. G. hirsutum contained 25% diisooctyl ester. The whitefly feeding assay with Nile Blue dye showed no color in whiteflies gut fed on G. arboreum . In contrast, color was observed in the rest of whiteflies. From results, it was concluded that reduced quantity as well as absence of (1) 3-trifluoroacetoxytetradecane, (2) 2-piperidinone,n-|4-bromo-n-butyl|, (3) 4-heptafluorobutyroxypentadecane, (4) Silane, trichlorodocosyl-, (5) 6- Octadecenoic acid, methyl ester, and (6) Heptadecanoicacid,16-methyl-,methyl ester in wax could make plants susceptible to CLCuV , infested by whiteflies.

A novel synthetic quantification standard including virus and internal report targets: application for the detection and quantification of emerging begomoviruses on tomato.

Science.gov (United States)

Péréfarres, Frédéric; Hoareau, Murielle; Chiroleu, Frédéric; Reynaud, Bernard; Dintinger, Jacques; Lett, Jean-Michel

2011-08-05

Begomovirus is a genus of phytopathogenic single-stranded DNA viruses, transmitted by the whitefly Bemisia tabaci. This genus includes emerging and economically significant viruses such as those associated with Tomato Yellow Leaf Curl Disease, for which diagnostic tools are needed to prevent dispersion and new introductions. Five real-time PCRs with an internal tomato reporter gene were developed for accurate detection and quantification of monopartite begomoviruses, including two strains of the Tomato yellow leaf curl virus (TYLCV; Mld and IL strains), the Tomato leaf curl Comoros virus-like viruses (ToLCKMV-like viruses) and the two molecules of the bipartite Potato yellow mosaic virus. These diagnostic tools have a unique standard quantification, comprising the targeted viral and internal report amplicons. These duplex real-time PCRs were applied to artificially inoculated plants to monitor and compare their viral development. Real-time PCRs were optimized for accurate detection and quantification over a range of 2 × 10(9) to 2 × 10(3) copies of genomic viral DNA/μL for TYLCV-Mld, TYLCV-IL and PYMV-B and 2 × 10(8) to 2 × 10(3) copies of genomic viral DNA/μL for PYMV-A and ToLCKMV-like viruses. These real-time PCRs were applied to artificially inoculated plants and viral loads were compared at 10, 20 and 30 days post-inoculation. Different patterns of viral accumulation were observed between the bipartite and the monopartite begomoviruses. Interestingly, PYMV accumulated more viral DNA at each date for both genomic components compared to all the monopartite viruses. Also, PYMV reached its highest viral load at 10 dpi contrary to the other viruses (20 dpi). The accumulation kinetics of the two strains of emergent TYLCV differed from the ToLCKMV-like viruses in the higher quantities of viral DNA produced in the early phase of the infection and in the shorter time to reach this peak viral load. To detect and quantify a wide range of begomoviruses, five duplex

A novel synthetic quantification standard including virus and internal report targets: application for the detection and quantification of emerging begomoviruses on tomato

Directory of Open Access Journals (Sweden)

Lett Jean-Michel

2011-08-01

Full Text Available Abstract Background Begomovirus is a genus of phytopathogenic single-stranded DNA viruses, transmitted by the whitefly Bemisia tabaci. This genus includes emerging and economically significant viruses such as those associated with Tomato Yellow Leaf Curl Disease, for which diagnostic tools are needed to prevent dispersion and new introductions. Five real-time PCRs with an internal tomato reporter gene were developed for accurate detection and quantification of monopartite begomoviruses, including two strains of the Tomato yellow leaf curl virus (TYLCV; Mld and IL strains, the Tomato leaf curl Comoros virus-like viruses (ToLCKMV-like viruses and the two molecules of the bipartite Potato yellow mosaic virus. These diagnostic tools have a unique standard quantification, comprising the targeted viral and internal report amplicons. These duplex real-time PCRs were applied to artificially inoculated plants to monitor and compare their viral development. Results Real-time PCRs were optimized for accurate detection and quantification over a range of 2 × 109 to 2 × 103 copies of genomic viral DNA/μL for TYLCV-Mld, TYLCV-IL and PYMV-B and 2 × 108 to 2 × 103 copies of genomic viral DNA/μL for PYMV-A and ToLCKMV-like viruses. These real-time PCRs were applied to artificially inoculated plants and viral loads were compared at 10, 20 and 30 days post-inoculation. Different patterns of viral accumulation were observed between the bipartite and the monopartite begomoviruses. Interestingly, PYMV accumulated more viral DNA at each date for both genomic components compared to all the monopartite viruses. Also, PYMV reached its highest viral load at 10 dpi contrary to the other viruses (20 dpi. The accumulation kinetics of the two strains of emergent TYLCV differed from the ToLCKMV-like viruses in the higher quantities of viral DNA produced in the early phase of the infection and in the shorter time to reach this peak viral load. Conclusions To detect and

Nucleotide sequence of a chickpea chlorotic stunt virus relative that infects pea and faba bean in China.

Science.gov (United States)

Zhou, Cui-Ji; Xiang, Hai-Ying; Zhuo, Tao; Li, Da-Wei; Yu, Jia-Lin; Han, Cheng-Gui

2012-07-01

We determined the genome sequence of a new polerovirus that infects field pea and faba bean in China. Its entire nucleotide sequence (6021 nt) was most closely related (83.3% identity) to that of an Ethiopian isolate of chickpea chlorotic stunt virus (CpCSV-Eth). With the exception of the coat protein (encoded by ORF3), amino acid sequence identities of all gene products of this virus to those of CpCSV-Eth and other poleroviruses were Polerovirus, and the name pea mild chlorosis virus is proposed.

Serological and molecular epidemiology of Japanese encephalitis virus infections in swine herds in China, 2006-2012.

Science.gov (United States)

Chai, Chunxia; Wang, Qiao; Cao, Sanjie; Zhao, Qin; Wen, Yiping; Huang, Xiaobo; Wen, Xintian; Yan, Qiguai; Ma, Xiaoping; Wu, Rui

2018-01-31

Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing viral encephalitis in humans and reproductive disorder in swine. JEV is prevalent throughout China in human; however, spatiotemporal analysis of JEV in Chinese swine herds has not been reported previously. Herein, we present serological and molecular epidemiological results and estimates of prevalence of JEV infections among swine herds in various regions of China. The results suggest that JEV infections are widespread and genotype I and III strains co-exist in the same regions. Therefore, there is an urgent need to monitor JEV infection status among swine herds in China.

Antibodies against Severe Fever with Thrombocytopenia Syndrome Virus in Healthy Persons, China, 2013

Science.gov (United States)

Zhang, Lei; Sun, Jimin; Yan, Jie; Lv, Huakun; Chai, Chengliang; Sun, Yi; Shao, Bin; Jiang, Jianmin; Chen, Zhiping

2014-01-01

In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding suggests that most natural infections with SFTSV are mild or subclinical. PMID:25061813

Wind Stress, METOP ASCAT, 0.25 degrees, Global, Near Real Time, Curl

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

Surveillance of Hepatitis E Virus Contamination in Shellfish in China

Directory of Open Access Journals (Sweden)

Shenyang Gao

2015-02-01

Full Text Available Background: Hepatitis E virus (HEV has been confirmed to be a zoonotic virus of worldwide distribution. HEV contamination in the water environment has not been well examined in China. The objective of this study was to evaluate HEV contamination in shellfish in a coastal area of China. Such contamination would be significant for evaluating public health risks. Methods: samples of three species shellfish were collected from thirteen points of estuarine tidal flats around the Bohai Gulf and screened for HEV RNA using an in-house nested RT-PCR assay. The detected HEV-positive samples were further verified by gene cloning and sequencing analysis. Results: the overall HEV-positive detection rate is approximately 17.5% per kilogram of shellfish.  HEV was more common among S. subcrenata (28.2%, followed by A. granosa (14.3% and R. philippinarum (11.5%. The phylogenetic analysis of the 13 HEV strains detected revealed that gene fragments fell into two known 4 sub-genotypes (4b/4d groups and another unknown group. Conclusions: 13 different sub-genotype 4 HEVs were found in contaminated shellfish in the Bohai Gulf rim. The findings suggest that a health risk may exist for users of waters in the Bonhai area and to consumers of shellfish.  Further research is needed to assess the sources and infectivity of HEV in these settings, and to evaluate additional shellfish harvesting areas.

Genetic Characterization of Continually Evolving Highly Pathogenic H5N6 Influenza Viruses in China, 2012-2016.

Science.gov (United States)

Li, Meng; Zhao, Na; Luo, Jing; Li, Yuan; Chen, Lin; Ma, Jiajun; Zhao, Lin; Yuan, Guohui; Wang, Chengmin; Wang, Yutian; Liu, Yanhua; He, Hongxuan

2017-01-01

H5N6 is a highly pathogenic avian influenza (HPAI) and a zoonotic disease that causes recurring endemics in East Asia. At least 155 H5N6 outbreaks, including 15 human infections, have been reported in China. These repeated outbreaks have increased concern that the H5N6 virus may cross over to humans and cause a pandemic. In February, 2016, peafowls in a breeding farm exhibited a highly contagious disease. Post-mortem examinations, including RT-PCR, and virus isolation, confirmed that the highly pathogenic H5N6 influenza virus was the causative agent, and the strain was named A/ Pavo Cristatus /Jiangxi/JA1/2016. In animal experiments, it exhibited high pathogenicity in chickens and an estimated median lethal dose in mice of ~10 4.3 TCID 50 . A phylogenetic analysis showed that JA1/2016 was clustered in H5 clade 2.3.4.4. FG594-like H5N6 virus from Guangdong Province was the probable predecessor of JA1/2016, and the estimated divergence time was June 2014. Furthermore, we found that H5N6 influenza viruses can be classified into the two following groups: Group 1 and Group 2. Group 2 influenza viruses have not been detected since the end of 2014, whereas Group 1 influenza viruses have continually evolved and reassorted with the "gene pool" circulating in south China, resulting in the rise of novel subtypes of this influenza virus. An increase in the number of its identified hosts, the expanding range of its distribution, and the continual evolution of H5N6 AIVs enhance the risk that an H5N6 virus may spread to other continents and cause a pandemic.

Molecular and phylogenetic characterization of honey bee viruses, Nosema microsporidia, protozoan parasites, and parasitic mites in China.

Science.gov (United States)

Yang, Bu; Peng, Guangda; Li, Tianbang; Kadowaki, Tatsuhiko

2013-02-01

China has the largest number of managed honey bee colonies, which produce the highest quantity of honey and royal jelly in the world; however, the presence of honey bee pathogens and parasites has never been rigorously identified in Chinese apiaries. We thus conducted a molecular survey of honey bee RNA viruses, Nosema microsporidia, protozoan parasites, and tracheal mites associated with nonnative Apis mellifera ligustica and native Apis cerana cerana colonies in China. We found the presence of black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Israeli acute paralysis virus (IAPV), and sacbrood virus (SBV), but not that of acute bee paralysis virus (ABPV) or Kashmir bee virus (KBV). DWV was the most prevalent in the tested samples. Phylogenies of Chinese viral isolates demonstrated that genetically heterogeneous populations of BQCV, CBPV, DWV, and A. cerana-infecting SBV, and relatively homogenous populations of IAPV and A. meliifera-infecting new strain of SBV with single origins, are spread in Chinese apiaries. Similar to previous observations in many countries, Nosema ceranae, but not Nosema apis, was prevalent in the tested samples. Crithidia mellificae, but not Apicystis bombi was found in five samples, including one A. c. cerana colony, demonstrating that C. mellificae is capable of infecting multiple honey bee species. Based on kinetoplast-encoded cytochrome b sequences, the C. mellificae isolate from A. c. cerana represents a novel haplotype with 19 nucleotide differences from the Chinese and Japanese isolates from A. m. ligustica. This suggests that A. c. cerana is the native host for this specific haplotype. The tracheal mite, Acarapis woodi, was detected in one A. m. ligustica colony. Our results demonstrate that honey bee RNA viruses, N. ceranae, C. mellificae, and tracheal mites are present in Chinese apiaries, and some might be originated from native Asian honey bees.

Phylogenetic analysis of canine distemper virus in domestic dogs in Nanjing, China.

Science.gov (United States)

Bi, Zhenwei; Wang, Yongshan; Wang, Xiaoli; Xia, Xingxia

2015-02-01

Canine distemper virus (CDV) infects a broad range of carnivores, including wild and domestic Canidae. The hemagglutinin gene, which encodes the attachment protein that determines viral tropism, has been widely used to determine the relationship between CDV strains of different lineages circulating worldwide. We determined the full-length H gene sequences of seven CDV field strains detected in domestic dogs in Nanjing, China. A phylogenetic analysis of the H gene sequences of CDV strains from different geographic regions and vaccine strains was performed. Four of the seven CDV strains were grouped in the same cluster of the Asia-1 lineage to which the vast majority of Chinese CDV strains belong, whereas the other three were clustered within the Asia-4 lineage, which has never been detected in China. This represents the first record of detection of strains of the Asia-4 lineage in China since this lineage was reported in Thailand in 2013.

Comparison of complete genome sequences of dog rabies viruses isolated from China and Mexico reveals key amino acid changes that may be associated with virus replication and virulence.

Science.gov (United States)

Yu, Fulai; Zhang, Guoqing; Zhong, Xiangfu; Han, Na; Song, Yunfeng; Zhao, Ling; Cui, Min; Rayner, Simon; Fu, Zhen F

2014-07-01

Rabies is a global problem, but its impact and prevalence vary across different regions. In some areas, such as parts of Africa and Asia, the virus is prevalent in the domestic dog population, leading to epidemic waves and large numbers of human fatalities. In other regions, such as the Americas, the virus predominates in wildlife and bat populations, with sporadic spillover into domestic animals. In this work, we attempted to investigate whether these distinct environments led to selective pressures that result in measurable changes within the genome at the amino acid level. To this end, we collected and sequenced the full genome of two isolates from divergent environments. The first isolate (DRV-AH08) was from China, where the virus is present in the dog population and the country is experiencing a serious epidemic. The second isolate (DRV-Mexico) was taken from Mexico, where the virus is present in both wildlife and domestic dog populations, but at low levels as a consequence of an effective vaccination program. We then combined and compared these with other full genome sequences to identify distinct amino acid changes that might be associated with environment. Phylogenetic analysis identified strain DRV-AH08 as belonging to the China-I lineage, which has emerged to become the dominant lineage in the current epidemic. The Mexico strain was placed in the D11 Mexico lineage, associated with the West USA-Mexico border clade. Amino acid sequence analysis identified only 17 amino acid differences in the N, G and L proteins. These differences may be associated with virus replication and virulence-for example, the short incubation period observed in the current epidemic in China.

Epidemiology of Classical Hodgkin Lymphoma and Its Association with Epstein Barr Virus in Northern China

NARCIS (Netherlands)

Huang, Xin; Nolte, Ilja; Gao, Zifen; Vos, Hans; Hepkema, Bouke; Poppema, Sibrand; van den Berg, Anke; Diepstra, Arjan

2011-01-01

Background: The incidence of classical Hodgkin lymphoma (cHL) and its association with Epstein-Barr virus (EBV) varies significantly with age, sex, ethnicity and geographic location. This is the first report on epidemiological features of cHL patients from Northern regions of China. These features

Phylogenetic and pathotypic characterization of Newcastle disease viruses circulating in South China and transmission in different birds

Directory of Open Access Journals (Sweden)

Yinfeng eKang

2016-02-01

Full Text Available Although Newcastle disease virus (NDV with high pathogenicity has frequently been isolated in poultry in China since 1948, the mode of its transmission among avian species remains largely unknown. Given that various wild bird species have been implicated as sources of transmission, in this study we genotypically and pathotypically characterized 23 NDV isolates collected from chickens, ducks, and pigeons in live bird markets (LBMs in South China as part of an H7N9 surveillance program during December 2013–February 2014. To simulate the natural transmission of different kinds of animals in LBMs, we selected three representative NDVs—namely, GM, YF18, and GZ289—isolated from different birds to evaluate the pathogenicity and transmission of the indicated viruses in chickens, ducks, and pigeons. Furthermore, to investigate the replication and shedding of NDV in poultry, we inoculated the chickens, ducks, and pigeons with 106 EID50 of each virus via intraocular and intranasal routes. Eight h after infection, the naïve contact groups were housed with those inoculated with each of the viruses as a means to monitor contact transmission. Our results indicated that genetically diverse viruses circulate in LBMs in South China’s Guangdong Province and that NDV from different birds have different tissue tropisms and host ranges when transmitted in different birds. We therefore propose the continuous epidemiological surveillance of LBMs to support the prevention of the spread of these viruses in different birds, especially chickens, and highlight the need for studies of the virus–host relationship.

Serological and molecular epidemiology of Japanese encephalitis virus infections in swine herds in China, 2006–2012

Science.gov (United States)

Chai, Chunxia; Wang, Qiao; Cao, Sanjie; Zhao, Qin; Wen, Yiping; Huang, Xiaobo; Wen, Xintian; Yan, Qiguai; Ma, Xiaoping

2018-01-01

Japanese encephalitis virus (JEV) is a mosquito-borne, zoonotic flavivirus causing viral encephalitis in humans and reproductive disorder in swine. JEV is prevalent throughout China in human; however, spatiotemporal analysis of JEV in Chinese swine herds has not been reported previously. Herein, we present serological and molecular epidemiological results and estimates of prevalence of JEV infections among swine herds in various regions of China. The results suggest that JEV infections are widespread and genotype I and III strains co-exist in the same regions. Therefore, there is an urgent need to monitor JEV infection status among swine herds in China. PMID:28693301

Incidence of human rabies and characterization of rabies virus nucleoprotein gene in dogs in Fujian Province, Southeast China, 2002-2012.

Science.gov (United States)

Zhang, Jian-Ming; Zhang, Zhi-Shan; Deng, Yan-Qin; Wu, Shou-Li; Wang, Wei; Yan, Yan-Sheng

2017-08-30

Rabies is a global fatal infectious viral disease that is characterized by a high mortality after onset of clinical symptoms. Recently, there has been an increase in the incidence of rabies in China. The aim of this study was to investigate the incidence of human rabies and characterize the rabies virus nucleoprotein gene in dogs sampled from Fujian Province, Southeast China from 2002 to 2012. Data pertaining to human rabies cases in Fujian Province during the period from 2002 through 2012 were collected, and the epidemiological profiles were described. The saliva and brain specimens were collected from dogs in Quanzhou, Longyan and Sanming cities of the province, and the rabies virus antigen was determined in the canine saliva specimens using an ELISA assay. Rabies virus RNA was extracted from canine brain specimens, and rabies virus nucleoprotein gene was amplified using a nested RT-PCR assay, followed by sequencing and genotyping. A total of 226 human rabies cases were reported in Fujian Province from 2002 to 2012, in which 197 cases were detected in three cities of Quanzhou, Longyan and Sanming. ELISA assay revealed positive rabies virus antigen in six of eight rabid dogs and 165 of 3492 seemingly healthy dogs. The full-length gene fragment of the rabies virus nucleoprotein gene was amplified from the brain specimens of seven rabid dogs and 12 seemingly healthy dogs. Sequence alignment and phylogenetic analysis revealed that these 19 rabies virus nucleoprotein genes all belonged to genotype I, and were classified into three genetic groups. Sequencing analysis showed a 99.7% to 100% intra-group and an 86.4% to 89.3% inter-group homology. This study is the first description pertaining to the epidemiological characteristics of human rabies cases and characterization of the rabies virus nucleoprotein gene in dogs in Fujian Province, Southeast China. Our findings may provide valuable knowledge for the development of strategies targeting the prevention and control of

[Establishment of Quality Control System of Nucleic Acid Detection for Ebola Virus in Sierra Leone-China Friendship Biological Safety Laboratory].

Science.gov (United States)

Wang, Qin; Zhang, Yong; Nie, Kai; Wang, Huanyu; Du, Haijun; Song, Jingdong; Xiao, Kang; Lei, Wenwen; Guo, Jianqiang; Wei, Hejiang; Cai, Kun; Wang, Yanhai; Wu, Jiang; Gerald, Bangura; Kamara, Idrissa Laybohr; Liang, Mifang; Wu, Guizhen; Dong, Xiaoping

2016-03-01

The quality control process throughout the Ebola virus nucleic acid detection in Sierra Leone-China Friendship Biological Safety Laboratory (SLE-CHN Biosafety Lab) was described in detail, in order to comprehensively display the scientific, rigorous, accurate and efficient practice in detection of Ebola virus of first batch detection team in SLE-CHN Biosafety Lab. Firstly, the key points of laboratory quality control system was described, including the managements and organizing, quality control documents and information management, instrument, reagents and supplies, assessment, facilities design and space allocation, laboratory maintenance and biosecurity. Secondly, the application of quality control methods in the whole process of the Ebola virus detection, including before the test, during the test and after the test, was analyzed. The excellent and professional laboratory staffs, the implementation of humanized management are the cornerstone of the success; High-level biological safety protection is the premise for effective quality control and completion of Ebola virus detection tasks. And professional logistics is prerequisite for launching the laboratory diagnosis of Ebola virus. The establishment and running of SLE-CHN Biosafety Lab has landmark significance for the friendship between Sierra Leone and China, and the lab becomes the most important base for Ebola virus laboratory testing in Sierra Leone.

Genetic Characterization of Continually Evolving Highly Pathogenic H5N6 Influenza Viruses in China, 2012–2016

Science.gov (United States)

Li, Meng; Zhao, Na; Luo, Jing; Li, Yuan; Chen, Lin; Ma, Jiajun; Zhao, Lin; Yuan, Guohui; Wang, Chengmin; Wang, Yutian; Liu, Yanhua; He, Hongxuan

2017-01-01

H5N6 is a highly pathogenic avian influenza (HPAI) and a zoonotic disease that causes recurring endemics in East Asia. At least 155 H5N6 outbreaks, including 15 human infections, have been reported in China. These repeated outbreaks have increased concern that the H5N6 virus may cross over to humans and cause a pandemic. In February, 2016, peafowls in a breeding farm exhibited a highly contagious disease. Post-mortem examinations, including RT-PCR, and virus isolation, confirmed that the highly pathogenic H5N6 influenza virus was the causative agent, and the strain was named A/Pavo Cristatus/Jiangxi/JA1/2016. In animal experiments, it exhibited high pathogenicity in chickens and an estimated median lethal dose in mice of ~104.3 TCID50. A phylogenetic analysis showed that JA1/2016 was clustered in H5 clade 2.3.4.4. FG594-like H5N6 virus from Guangdong Province was the probable predecessor of JA1/2016, and the estimated divergence time was June 2014. Furthermore, we found that H5N6 influenza viruses can be classified into the two following groups: Group 1 and Group 2. Group 2 influenza viruses have not been detected since the end of 2014, whereas Group 1 influenza viruses have continually evolved and reassorted with the “gene pool” circulating in south China, resulting in the rise of novel subtypes of this influenza virus. An increase in the number of its identified hosts, the expanding range of its distribution, and the continual evolution of H5N6 AIVs enhance the risk that an H5N6 virus may spread to other continents and cause a pandemic. PMID:28293218

Wind Stress, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality, Curl

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

Identification and phylogenetic analysis of a sheep pox virus isolated from the Ningxia Hui Autonomous Region of China.

Science.gov (United States)

Zhu, X L; Yang, F; Li, H X; Dou, Y X; Meng, X L; Li, H; Luo, X N; Cai, X P

2013-05-14

An outbreak of sheep pox was investigated in the Ningxia Hui Autonomous Region in China. Through immunofluorescence testing, isolated viruses, polymerase chain reaction identification, and electron microscopic examination, the isolated strain was identified as a sheep pox virus. The virus was identified through sequence and phylogenetic analysis of the P32 gene, open reading frame (ORF) 095, and ORF 103 genes. This study is the first to use the ORF 095 and ORF 103 genes as candidate genes for the analysis of sheep pox. The results showed that the ORF 095 and ORF 103 genes could be used for the genotyping of the sheep pox virus.

The seroprevalence of pandemic influenza H1N1 (2009 virus in China.

Directory of Open Access Journals (Sweden)

Cuiling Xu

2011-04-01

Full Text Available Mainland China experienced pandemic influenza H1N1 (2009 virus (pH1N1 with peak activity during November-December 2009. To understand the geographic extent, risk factors, and attack rate of pH1N1 infection in China we conducted a nationwide serological survey to determine the prevalence of antibodies to pH1N1.Stored serum samples (n = 2,379 collected during 2006-2008 were used to estimate baseline serum reactogenicity to pH1N1. In January 2010, we used a multistage-stratified random sampling method to select 50,111 subjects who met eligibility criteria and collected serum samples and administered a standardized questionnaire. Antibody response to pH1N1 was measured using haemagglutination inhibition (HI assay and the weighted seroprevalence was calculated using the Taylor series linearization method. Multivariable logistic regression analyses were used to examine risk factors for pH1N1 seropositivity. Baseline seroprevalence of pH1N1 antibody (HI titer ≥40 was 1.2%. The weighted seroprevalence of pH1N1 among the Chinese population was 21.5%(vaccinated: 62.0%; unvaccinated: 17.1%. Among unvaccinated participants, those aged 6-15 years (32.9% and 16-24 years (30.3% had higher seroprevalence compared with participants aged 25-59 years (10.7% and ≥60 years (9.9%, P<0.0001. Children in kindergarten and students had higher odds of seropositivity than children in family care (OR: 1.36 and 2.05, respectively. We estimated that 207.7 million individuals (15.9% experienced pH1N1 infection in China.The Chinese population had low pre-existing immunity to pH1N1 and experienced a relatively high attack rate in 2009 of this virus. We recommend routine control measures such as vaccination to reduce transmission and spread of seasonal and pandemic influenza viruses.

Epidemiology, Evolution, and Recent Outbreaks of Avian Influenza Virus in China.

Science.gov (United States)

Su, Shuo; Bi, Yuhai; Wong, Gary; Gray, Gregory C; Gao, George F; Li, Shoujun

2015-09-01

Novel reassortants of H7N9, H10N8, and H5N6 avian influenza viruses (AIVs) are currently circulating in China's poultry flocks, occasionally infecting humans and other mammals. Combined with the sometimes enzootic H5N1 and H9N2 strains, this cauldron of genetically diverse AIVs pose significant risks to public health. Here, we review the epidemiology, evolution, and recent outbreaks of AIVs in China, discuss reasons behind the recent increase in the emergence of novel AIVs, and identify warning signs which may point to the emergence of a potentially virulent and highly transmissible AIV to humans. This review will be useful to authorities who consider options for the detection and control of AIV transmission in animals and humans, with the goal of preventing future epidemics and pandemics. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Complete genome sequence of a novel H9N2 subtype influenza virus FJG9 strain in China reveals a natural reassortant event.

Science.gov (United States)

Xie, Qingmei; Yan, Zhuanqiang; Ji, Jun; Zhang, Huanmin; Liu, Jun; Sun, Yue; Li, Guangwei; Chen, Feng; Xue, Chunyi; Ma, Jingyun; Bee, Yingzuo

2012-09-01

A/chicken/FJ/G9/09 (FJ/G9) is an H9N2 subtype avian influenza virus (H9N2 AIV) strain causing high morbidity that was isolated from broilers in Fujian Province of China in 2009. FJ/G9 has been used as the vaccine strain against H9N2 AIV infection in Fujian Province of China. Here, we report the complete genome sequence of FJ/G9 with natural six-way reassortment, which is the most complex genotype strain in China and even in the world so far. The present findings will aid in understanding the complexity and diversity of H9N2 subtype avian influenza virus.

Curling Edges: A Problem that Has Plagued Scrolls for Millennia

Science.gov (United States)

Chou, Ming-Han; Shen, Wei-Chao; Wang, Yi-Ping; Hung, Sun-Hsin; Hong, Tzay-Ming

2014-01-01

Qi-Wa refers to the up curl on the lengths of hand scrolls and hanging scrolls, which has troubled Chinese artisans and emperors for as long as the art of painting and calligraphy has existed. This warp is unwelcome not only for aesthetic reasons, but its potential damage to the fiber and ink. Although it is generally treated as a part of the cockling and curling due to moisture, consistency of paste, and defects from the mounting procedures, we demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing Qi-Wa. In contrast to the former factors whose effects are less predictable, the plastic deformation and strain distribution on a membrane are a well-defined mechanical problem. We study this phenomenon by experiments, theoretical models, and molecular dynamics simulation, and obtain consistent scaling relations for the Qi-Wa height. This knowledge enables us to propose modifications on the traditional mounting techniques that are tested on real mounted paper to be effective at mitigating Qi-Wa. By experimenting on polymer-based films, we demonstrate the possible relevance of our study to the modern development of flexible electronic paper.

Virus surveys of Capsicum spp. in the Republic of Benin reveal the prevalence of pepper vein yellows virus and the identification of a previously uncharacterised polerovirus species.

Science.gov (United States)

Afouda, Leonard; Kone, Daouda; Zinsou, Valerien; Dossou, Laurence; Kenyon, Lawrence; Winter, Stephan; Knierim, Dennis

2017-06-01

Surveys were conducted in 2014 and 2015 in Southern and Northern Benin, respectively, to identify the viruses infecting peppers (Capsicum spp.). The samples were screened by ELISA for cucumber mosaic virus (CMV), pepper veinal mottle virus (PVMV), potato virus Y (PVY) and tomato yellow leaf curl virus (TYLCV). A generic reverse transcription PCR (RT-PCR) was used to test for the presence of poleroviruses. ELISA tests confirmed the prevalence of all viruses, while the RT-PCR detected pepper vein yellows virus (PeVYV) which is reported for the first time in Benin. A further, divergent polerovirus isolate was detected from a single pepper sample originating from southern Benin. Screening of samples collected from solanaceous plants during virus surveys in Mali (conducted in 2009) also detected this divergent polerovirus isolate in two samples from African eggplants. The complete genome sequence was obtained from the Mali isolate using transcriptome sequencing and by conventional Sanger sequencing of overlapping RT-PCR products. Based on the sequence characteristics of this isolate we propose a new polerovirus species, African eggplant yellowing virus (AeYV).

Update: Increase in Human Infections with Novel Asian Lineage Avian Influenza A(H7N9) Viruses During the Fifth Epidemic - China, October 1, 2016-August 7, 2017.

Science.gov (United States)

Kile, James C; Ren, Ruiqi; Liu, Liqi; Greene, Carolyn M; Roguski, Katherine; Iuliano, A Danielle; Jang, Yunho; Jones, Joyce; Thor, Sharmi; Song, Ying; Zhou, Suizan; Trock, Susan C; Dugan, Vivien; Wentworth, David E; Levine, Min Z; Uyeki, Timothy M; Katz, Jacqueline M; Jernigan, Daniel B; Olsen, Sonja J; Fry, Alicia M; Azziz-Baumgartner, Eduardo; Davis, C Todd

2017-09-08

Among all influenza viruses assessed using CDC's Influenza Risk Assessment Tool (IRAT), the Asian lineage avian influenza A(H7N9) virus (Asian H7N9), first reported in China in March 2013,* is ranked as the influenza virus with the highest potential pandemic risk (1). During October 1, 2016-August 7, 2017, the National Health and Family Planning Commission of China; CDC, Taiwan; the Hong Kong Centre for Health Protection; and the Macao CDC reported 759 human infections with Asian H7N9 viruses, including 281 deaths, to the World Health Organization (WHO), making this the largest of the five epidemics of Asian H7N9 infections that have occurred since 2013 (Figure 1). This report summarizes new viral and epidemiologic features identified during the fifth epidemic of Asian H7N9 in China and summarizes ongoing measures to enhance pandemic preparedness. Infections in humans and poultry were reported from most areas of China, including provinces bordering other countries, indicating extensive, ongoing geographic spread. The risk to the general public is very low and most human infections were, and continue to be, associated with poultry exposure, especially at live bird markets in mainland China. Throughout the first four epidemics of Asian H7N9 infections, only low pathogenic avian influenza (LPAI) viruses were detected among human, poultry, and environmental specimens and samples. During the fifth epidemic, mutations were detected among some Asian H7N9 viruses, identifying the emergence of high pathogenic avian influenza (HPAI) viruses as well as viruses with reduced susceptibility to influenza antiviral medications recommended for treatment. Furthermore, the fifth-epidemic viruses diverged genetically into two separate lineages (Pearl River Delta lineage and Yangtze River Delta lineage), with Yangtze River Delta lineage viruses emerging as antigenically different compared with those from earlier epidemics. Because of its pandemic potential, candidate vaccine viruses

Two different genotypes of H1N2 swine influenza virus isolated in northern China and their pathogenicity in animals.

Science.gov (United States)

Yang, Huanliang; Chen, Yan; Qiao, Chuanling; Xu, Chuantian; Yan, Minghua; Xin, Xiaoguang; Bu, Zhigao; Chen, Hualan

2015-02-25

During 2006 and 2007, two swine-origin triple-reassortant influenza A (H1N2) viruses were isolated from pigs in northern China, and the antigenic characteristics of the hemagglutinin protein of the viruses were examined. Genotyping and phylogenetic analyses demonstrated different emergence patterns for the two H1N2 viruses, Sw/Hebei/10/06 and Sw/Tianjin/1/07. Sequences for the other genes encoding the internal proteins were compared with the existing data to determine their origins and establish the likely mechanisms of genetic reassortment. Sw/Hebei/10/06 is an Sw/Indiana/9K035/99-like virus, whereas Sw/Tianjin/1/07 represents a new H1N2 genotype with surface genes of classic swine and human origin and internal genes originating from the Eurasian avian-like swine H1N1 virus. Six-week-old female BALB/c mice infected with the Sw/HeB/10/06 and Sw/TJ/1/07 viruses showed an average weight loss of 12.8% and 8.1%, respectively. Healthy six-week-old pigs were inoculated intranasally with either the Sw/HeB/10/06 or Sw/TJ/1/07 virus. No considerable changes in the clinical presentation were observed post-inoculation in any of the virus-inoculated groups, and the viruses effectively replicated in the nasal cavity and lung tissue. Based on the results, it is possible that the new genotype of the swine H1N2 virus that emerged in China may become widespread in the swine population and pose a potential threat to public health. Copyright © 2014 Elsevier B.V. All rights reserved.

The off-shore Transport of China Coastal Current over Taiwan Bank in Winter

Science.gov (United States)

Liao, E.; Yan, X. H.; Oey, L. Y.; Jiang, Y.

2016-12-01

In winter, an off-shore flow of China Coastal Current can be inferred from satellite and in-situ data over the Taiwan Bank. The dynamics related to this off-shore flow have not been previously explained and are examined here using observations and model. Influenced by southward wind stress and opposing pressure gradient, currents over the Taiwan Bank can be classified into three regimes. The southward China Coastal Current flows pass the Taiwan Bank when the wind stress is stronger than a critical value which depends on the opposite pressure gradient force. The coastal current turns northward under a weak wind stress. Two opposite currents converge over the bank and a branch of the coastal current then turns into the northward warm current when these two forces are in balance. Analysis of the vorticity balance shows that the cross-isobath movement is related to a negative bottom stress curl over the Taiwan Bank. Both bottom Ekman transport and shear and curvature vorticity related to the weak bottom slope over the Taiwan Bank contribute to the bottom stress curl. Composite analyses using observations tend to support the model results.

Observability of the effects of curl-free magnetic vector potential on ...

Indian Academy of Sciences (India)

We discuss here the prediction, based on a formalism by the author, on the observable effects of a curl-free magnetic vector potential on the macroscale as against the microscale of the Aharonov–Bohm effect. A new quantum concept – the 'transition amplitude wave' – postulated in the formalism has already been shown to ...

Effect of Live Poultry Market Interventions on Influenza A(H7N9) Virus, Guangdong, China

Science.gov (United States)

Wu, Jie; Lu, Jing; Faria, Nuno R.; Zeng, Xianqiao; Song, Yingchao; Zou, Lirong; Yi, Lina; Liang, Lijun; Ni, Hanzhong; Kang, Min; Zhang, Xin; Huang, Guofeng; Zhong, Haojie; Bowden, Thomas A.; Raghwani, Jayna; He, Jianfeng; He, Xiang; Lin, Jinyan; Koopmans, Marion; Pybus, Oliver G.

2016-01-01

Since March 2013, three waves of human infection with avian influenza A(H7N9) virus have been detected in China. To investigate virus transmission within and across epidemic waves, we used surveillance data and whole-genome analysis of viruses sampled in Guangdong during 2013–2015. We observed a geographic shift of human A(H7N9) infections from the second to the third waves. Live poultry market interventions were undertaken in epicenter cities; however, spatial phylogenetic analysis indicated that the third-wave outbreaks in central Guangdong most likely resulted from local virus persistence rather than introduction from elsewhere. Although the number of clinical cases in humans declined by 35% from the second to the third waves, the genetic diversity of third-wave viruses in Guangdong increased. Our results highlight the epidemic risk to a region reporting comparatively few A(H7N9) cases. Moreover, our results suggest that live-poultry market interventions cannot completely halt A(H7N9) virus persistence and dissemination. PMID:27869613

[Phylogenetic analysis of human/swine/avian gene reassortant H1N2 influenza A virus isolated from a pig in China].

Science.gov (United States)

Chen, Yixiang; Meng, Xueqiong; Liu, Qi; Huang, Xia; Huang, Shengbin; Liu, Cuiquan; Shi, Kaichuang; Guo, Jiangang; Chen, Fangfang; Hu, Liping

2008-04-01

Our aim in this study was to determine the genetic characterization and probable origin of the H1N2 swine influenza virus (A/Swine/Guangxi/13/2006) (Sw/GX/13/06) from lung tissue of a pig in Guangxi province, China. Eight genes of Sw/GX/13/06 were cloned and genetically analyzed. The hemagglutinin (HA), nucleoprotein (NP), matrix (M) and non-structural (NS) genes of Sw/GX/13/06 were most closely related to genes from the classical swine H1N1 influenza virus lineage. The neuraminidase (NA) and PB1 genes were most closely related to the corresponding genes from the human influenza H3N2 virus lineage. The remaining two genes PA and PB2 polymerase genes were most closely related to the genes from avian influenza virus lineage. Phylogenetic analyses revealed that Sw/GX/13/06 was a human/swine/avian H1N2 virus, and closely related to H1N2 viruses isolated from pigs in United States (1999-2001) and Korea (2002). To our knowledge, Sw/GX/13/06 was the first triple-reassortant H1N2 influenza A virus isolated from a pig in China. Whether the Sw/GX/13/06 has a potential threat to breeding farm and human health remains to be further investigated.

Nucleotide sequence analyses of genomic RNAs of peanut stunt virus Mi, the type strain representative of a novel PSV subgroup from China

NARCIS (Netherlands)

Yan, L.; Xu, Z.; Goldbach, R.W.; Chen, Y.K.; Prins, M.W.

2005-01-01

The complete nucleotide sequence of Peanut stunt virus strain Mi (PSV-Mi) from China was determined and compared to other viruses of the genus Cucumovirus. The tripartite genome of PSV-Mi encoded five open reading frames (ORFs) typical of cucumoviruses. Distance analyses of four ORFs indicated that

Tomato leaf curl Yunnan virus-encoded C4 induces cell division through enhancing stability of Cyclin D 1.1 via impairing NbSKη -mediated phosphorylation in Nicotiana benthamiana

Science.gov (United States)

Mei, Yuzhen; Yang, Xiuling; Huang, Changjun

2018-01-01

The whitefly-transmitted geminiviruses induce severe developmental abnormalities in plants. Geminivirus-encoded C4 protein functions as one of viral symptom determinants that could induce abnormal cell division. However, the molecular mechanism by which C4 contributes to cell division induction remains unclear. Here we report that tomato leaf curl Yunnan virus (TLCYnV) C4 interacts with a glycogen synthase kinase 3 (GSK3)/SHAGGY-like kinase, designed NbSKη, in Nicotiana benthamiana. Pro32, Asn34 and Thr35 of TLCYnV C4 are critical for its interaction with NbSKη and required for C4-induced typical symptoms. Interestingly, TLCYnV C4 directs NbSKη to the membrane and reduces the nuclear-accumulation of NbSKη. The relocalization of NbSKη impairs phosphorylation dependent degradation on its substrate-Cyclin D1.1 (NbCycD1;1), thereby increasing the accumulation level of NbCycD1;1 and inducing the cell division. Moreover, NbSKη-RNAi, 35S::NbCycD1;1 transgenic N. benthamiana plants have the similar phenotype as 35S::C4 transgenic N. benthamiana plants on callus-like tissue formation resulted from abnormal cell division induction. Thus, this study provides new insights into mechanism of how a viral protein hijacks NbSKη to induce abnormal cell division in plants. PMID:29293689

A novel synthetic quantification standard including virus and internal report targets: application for the detection and quantification of emerging begomoviruses on tomato

OpenAIRE

Péréfarres, Frédéric; Hoareau, Murielle; Chiroleu, Frédéric; Reynaud, Bernard; Dintinger, Jacques; Lett, Jean-Michel

2011-01-01

Abstract Background Begomovirus is a genus of phytopathogenic single-stranded DNA viruses, transmitted by the whitefly Bemisia tabaci. This genus includes emerging and economically significant viruses such as those associated with Tomato Yellow Leaf Curl Disease, for which diagnostic tools are needed to prevent dispersion and new introductions. Five real-time PCRs with an internal tomato reporter gene were developed for accurate detection and quantification of monopartite begomoviruses, inclu...

Filaggrin gene polymorphism associated with Epstein-Barr virus-associated tumors in China.

Science.gov (United States)

Yang, Yang; Liu, Wen; Zhao, Zhenzhen; Zhang, Yan; Xiao, Hua; Luo, Bing

2017-08-01

Mutations of filaggrin gene (FLG) have been identified as the cause of ichthyosis vulgaris, while recently FLG mutations were found to be associated with gastric cancer. This study aimed to investigate the association of filaggrin polymorphism with Epstein-Barr virus-associated tumors in China. A total of 200 patients with three types of tumors and 117 normal control samples were genotyped at three common FLG mutation loci (rs3126085, K4671X, R501X) by using Sequenom MassARRAY technique. The χ 2 test was used to evaluate the relationship between the mutation and the three kinds of tumors. A two-sided P value of Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and EBV-negative gastric carcinoma (EBVnGC), respectively. Furthermore, allele distributions in EBVaGC and EBVnGC were verified to be different in both SNP loci.

Hepatitis E Virus Serosurvey among Pet Dogs and Cats in Several Developed Cities in China

Science.gov (United States)

Sun, Long; Ji, Fangxiao; He, Shuyi; Zheng, Yun; Liang, Chumin; Zhang, Guihong; Su, Shuo; Li, Shoujun

2014-01-01

Infection by Hepatitis E virus (HEV), as a zoonotic disease virus, is well studied in pigs in China, but few studies in pets have been performed. This study was designed to characterize the prevalence of HEV infection among pet dogs and cats in major metropolitan areas of China. We conducted a seroepidemiological survey from 2012 to 2013 in 5 developed cities, Beijing, Shanghai, Canton, Shenzhen and Macao, by enzyme-linked immunosorbent assay (ELISA). The overall HEV seroprevalence in 658 dog and 191 cat serum samples was 21.12% and 6.28%, respectively. The analysis in dogs suggested that there were significant differences among cities, and the positive rate of HEV-specific antibody in all cities ranged from 6.06% (Shenzhen) to 29.34% (Beijing). Older pet cats have a high risk (OR, 10.25) for HEV seropositivity, but no strong relationship was observed between different genders and age groups. Additionally, it was revealed that stray dogs, omnivorous pet dogs and pet cats who share food, such as kitchen residue, with the general population would have a higher risk for HEV seropositivity. The odds ratios for these groups are 2.40, 2.83 and 5.39, respectively, compared with pet dogs and cats fed on commercial food. In this study, we first report that HEV is prevalent in pet dogs and cats in several large cities in China. Swill and kitchen residue may be a potential risk for HEV transmission from human to pets. As the sample size was relatively small in this study and may not be fully representative of China, further investigation is required to confirm the conclusions. PMID:24896257

Large-Deformation Curling Actuators Based on Carbon Nanotube Composite: Advanced-Structure Design and Biomimetic Application.

Science.gov (United States)

Chen, Luzhuo; Weng, Mingcen; Zhou, Zhiwei; Zhou, Yi; Zhang, Lingling; Li, Jiaxin; Huang, Zhigao; Zhang, Wei; Liu, Changhong; Fan, Shoushan

2015-12-22

In recent years, electroactive polymers have been developed as actuator materials. As an important branch of electroactive polymers, electrothermal actuators (ETAs) demonstrate potential applications in the fields of artificial muscles, biomimetic devices, robotics, and so on. Large-shape deformation, low-voltage-driven actuation, and ultrafast fabrication are critical to the development of ETA. However, a simultaneous optimization of all of these advantages has not been realized yet. Practical biomimetic applications are also rare. In this work, we introduce an ultrafast approach to fabricate a curling actuator based on a newly designed carbon nanotube and polymer composite, which completely realizes all of the above required advantages. The actuator shows an ultralarge curling actuation with a curvature greater than 1.0 cm(-1) and bending angle larger than 360°, even curling into a tubular structure. The driving voltage is down to a low voltage of 5 V. The remarkable actuation is attributed not only to the mismatch in the coefficients of thermal expansion but also to the mechanical property changes of materials during temperature change. We also construct an S-shape actuator to show the possibility of building advanced-structure actuators. A weightlifting walking robot is further designed that exhibits a fast-moving motion while lifting a sample heavier than itself, demonstrating promising biomimetic applications.

Identification of viral epitopes recognized by the immune system following vaccination and challenge with the H7N9 avian influenza virus from China

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In March of 2013, the first cases of H7N9 influenza were reported in humans in China, and shortly thereafter the virus was confirmed from poultry in live bird markets. Since that time the virus has persisted in both human and avian populations. The genetic composition of these H7N9 influenza virus...

Seed Transmission of Beet Curly Top Virus and Beet Curly Top Iran Virus in a Local Cultivar of Petunia in Iran

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Anabestani, Ameneh; Behjatnia, Seyed Ali Akbar; Izadpanah, Keramat; Tabein, Saeid

2017-01-01

Beet curly top virus (BCTV) and beet curly top Iran virus (BCTIV) are known as the causal agents of curly top disease in beet and several other dicotyledonous plants in Iran. These viruses are transmitted by Circulifer species, and until now, there has been no confirmed report of their seed transmission. A percentage (38.2–78.0%) of the seedlings developed from the seeds of a petunia local cultivar under insect-free conditions showed stunting, interveinal chlorosis, leaf curling, and vein swelling symptoms, and were infected by BCTV when tested by PCR. Presence of BCTV in seed extracts of petunia local cultivar was confirmed by PCR and IC-PCR, followed by sequencing. Agroinoculation of curly top free petunia plants with a BCTV infectious clone resulted in BCTV infection of plants and their developed seeds. These results show the seed infection and transmission of BCTV in a local cultivar of petunia. Similar experiments performed with BCTIV showed that this virus is also seed transmissible in the same cultivar of petunia, although with a lower rate (8.8–18.5%). Seed transmission of curly top viruses may have significant implications in the epidemiology of these viruses. PMID:29035342

Returning ex-patriot Chinese to Guangdong, China, increase the risk for local transmission of Zika virus.

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Sun, Jiufeng; Wu, De; Zhong, Haojie; Guan, Dawei; Zhang, Huan; Tan, Qiqi; Zhou, Huiqiong; Zhang, Meng; Ning, Dan; Zhang, Baohuan; Ke, Changwen; Song, Tie; Lin, Jinyan; Zhang, Yonghui; Koopmans, Marion; Gao, George F

2017-10-01

Fast expansion and linkage to microcephaly and Guillain Barre syndrome have made Zika virus (ZIKV) track attention of global health authority concerns. The epidemiology, virological characteristics and genetic evolution of introduced ZIKV to Guangdong, China, were investigated. Analyses of the epidemiological characteristics and genetic diversity of ZIKV isolates were performed. A total of twenty-eight confirmed ZIKV infection cases were imported into China in 2016, of which 19 were imported into Guangdong, China from Venezuela (16), the Samoa Islands (1), Suriname (1) and Guatemala (1). Serial sampling studies of the cases indicated longer shedding times of ZIKV particles from urine and saliva samples than from serum and conjunctiva swab samples. Seven ZIKV strains were successfully isolated from serum, urine and conjunctiva swab samples using cell culture and neonatal mouse injection methods. Genomic analysis indicated that all viruses belonged to the Asian lineage but had different evolutionary transmission routes with different geographic origins. The molecular clock phylogenetic analysis of the ZIKV genomes indicated independent local transmission that appeared to have been previously established in Venezuela and Samoa. Additionally, we found 7 unique non-synonymous mutations in the genomes of ZIKV that were imported to China. The mutations may indicate that ZIKV has undergone independent evolutionary history not caused by sudden adaptation to Chinese hosts. The increasing number of ex-patriot Chinese returning from ZIKV hyper-endemic areas to Guangdong combined with the presence of a variety of Aedes species indicate the potential for autochthonous transmission of ZIKV in Guangdong. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Top 10 plant viruses in molecular plant pathology.

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Scholthof, Karen-Beth G; Adkins, Scott; Czosnek, Henryk; Palukaitis, Peter; Jacquot, Emmanuel; Hohn, Thomas; Hohn, Barbara; Saunders, Keith; Candresse, Thierry; Ahlquist, Paul; Hemenway, Cynthia; Foster, Gary D

2011-12-01

Many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. However, to our knowledge, no such list exists. The aim of this review was to survey all plant virologists with an association with Molecular Plant Pathology and ask them to nominate which plant viruses they would place in a 'Top 10' based on scientific/economic importance. The survey generated more than 250 votes from the international community, and allowed the generation of a Top 10 plant virus list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Tobacco mosaic virus, (2) Tomato spotted wilt virus, (3) Tomato yellow leaf curl virus, (4) Cucumber mosaic virus, (5) Potato virus Y, (6) Cauliflower mosaic virus, (7) African cassava mosaic virus, (8) Plum pox virus, (9) Brome mosaic virus and (10) Potato virus X, with honourable mentions for viruses just missing out on the Top 10, including Citrus tristeza virus, Barley yellow dwarf virus, Potato leafroll virus and Tomato bushy stunt virus. This review article presents a short review on each virus of the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant virology community, as well as laying down a benchmark, as it will be interesting to see in future years how perceptions change and which viruses enter and leave the Top 10. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.

Immunogenicity of mumps virus vaccine candidates matching circulating genotypes in the United States and China.

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Zengel, James; Phan, Shannon I; Pickar, Adrian; Xu, Pei; He, Biao

2017-07-13

Mumps virus (MuV) causes acute infection in humans with characteristic swelling of the parotid gland. While vaccination has greatly reduced the incidence of MuV infection, there have been multiple large outbreaks of mumps virus (MuV) in highly vaccinated populations. The most common vaccine strain, Jeryl Lynn, belongs to genotype A, which is no longer a circulating genotype. We have developed two vaccine candidates that match the circulating genotypes in the United States (genotype G) and China (genotype F). We found that there was a significant decrease in the ability of the Jeryl Lynn vaccine to produce neutralizing antibody responses to non-matched viruses, when compared to either of our vaccine candidates. Our data suggests that an updated vaccine may allow for better immunity against the circulating MuV genotypes G and F. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular diagnostic development for begomovirus-betasatellite complexes undergoing diversification: A case study.

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Brown, Judith K; Ur-Rehman, Muhammad Zia; Avelar, Sofia; Chingandu, N; Hameed, Usman; Haider, Saleem; Ilyas, Muhammad

2017-09-15

At least five begomoviral species that cause leaf curl disease of cotton have emerged recently in Asia and Africa, reducing fiber quality and yield. The potential for the spread of these viruses to other cotton-vegetable growing regions throughout the world is extensive, owing to routine, global transport of alternative hosts of the leaf curl viruses, especially ornamentals. The research reported here describes the design and validation of polymerase chain reaction (PCR) primers undertaken to facilitate molecular detection of the two most-prevalent leaf curl-associated begomovirus-betasatellite complexes in the Indian Subcontinent and Africa, the Cotton leaf curl Kokhran virus-Burewala strain and Cotton leaf curl Gezira virus, endemic to Asia and Africa, respectively. Ongoing genomic diversification of these begomoviral-satellite complexes was evident based on nucleotide sequence alignments, and analysis of single nucleotide polymorphisms, both factors that created new challenges for primer design. The additional requirement for species and strain-specific, and betasatellite-specific primer design, imposes further constraints on primer design and validation due to the large number of related species and strains extant in 'core leaf curl virus complex', now with expanded distribution in south Asia, the Pacific region, and Africa-Arabian Peninsula that have relatively highly conserved coding and non-coding regions, which precludes much of the genome-betasatellite sequence when selecting primer 'targets'. Here, PCR primers were successfully designed and validated for detection of cloned viral genomes and betasatellites for representative 'core leaf curl' strains and species, distant relatives, and total DNA isolated from selected plant species. The application of molecular diagnostics to screen plant imports prior to export or release from ports of entry is expected to greatly reduce the likelihood of exotic leaf curl virus introductions that could dramatically affect

Seroprevalence of Hepatitis E Virus in Four Species of Parrots in China

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Xiao-Xuan Zhang, Nian-Zhang Zhang, Dong-Hui Zhou, Wei-Peng Tian, Ying-Tian Xu and Xing-Quan Zhu

2014-01-01

Full Text Available In this study, antibodies against avian Hepatitis E Virus (avian HEV were detected in 6.43% of examined serum samples (n=311 from budgerigars (Melopsittacus undulatus, lovebirds (Agapornis sp., cockatiel (Nymphicus hollandicus and Alexandrine parakeets (Psittacula eupatria by indirect ELISA. Seroprevalence of avian HEV infection in different parrot species varied from 0 to 7.92%. Statistical analysis of the origins of parrots demonstrated that parrots from Weifang city had a higher avian HEV seropositivity (7.84% compared with parrots from Beijing city (5.06%. The seroprevalence in parrots of different age groups varied from 4 to 7.62%. The avian HEV seroprevalence in parrots examined in spring and summer was 7.19 and 5.81%, respectively. This is the first report of avian HEV seroprevalence in four species of parrots in China, which will provide base-line data for the control of HEV infection in parrots in China.

Genetic characterization of H1N2 swine influenza virus isolated in China and its pathogenesis and inflammatory responses in mice.

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Zhang, Yan; Wang, Nan; Cao, Jiyue; Chen, Huanchun; Jin, Meilin; Zhou, Hongbo

2013-09-01

In 2009, two H1N2 influenza viruses were isolated from trachea swabs of pigs in Hubei in China. We compared these sequences with the other 18 complete genome sequences of swine H1N2 isolates from China during 2004 to 2010 and undertook extensive analysis of their evolutionary patterns. Six different genotypes - two reassortants between triple reassortant (TR) H3N2 and classical swine (CS) H1N1 virus, three reassortants between TR H1N2, Eurasian avian-like H1N1 swine virus and H9N2 swine virus, and one reassortant between H1N1, H3N2 human virus and CS H1N1 virus - were observed in these 20 swine H1N2 isolates. The TR H1N2 swine virus is the predominant genotype, and the two Hubei H1N2 isolates were located in this cluster. We also used a mouse model to examine the pathogenesis and inflammatory responses of the two isolates. The isolates replicated efficiently in the lung, and exhibited a strong inflammatory response, serious pathological changes and mortality in infected mice. Given the role that swine can play as putative "genetic mixing vessels" and the observed transmission of TR H1N2 in ferrets, H1N2 influenza surveillance in pigs should be increased to minimize the potential threat to public health.

Detection of viruses and atypical bacteria associated with acute respiratory infection of children in Hubei, China.

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Wu, Zegang; Li, Yan; Gu, Jian; Zheng, Hongyun; Tong, Yongqing; Wu, Qing

2014-02-01

Acute respiratory infection is the major cause of disease and death in children, particularly in developing countries. However, the spectrum of pathogenic viruses and atypical bacteria that exist in many of these countries remains incompletely characterized. The aim of this study was to examine the spectrum of pathogenic viruses and atypical bacteria associated with acute respiratory infection in children under the age of 16. A total of 10 435 serum sera specimens were collected from hospitalized children presenting with acute respiratory infection symptoms. Indirect immunofluorescence assays were performed to detect immunoglobulin M antibodies against nine common pathogens: mycoplasma pneumonia, influenza virus B, respiratory syncytial virus, parainfluenza virus, adenovirus, influenza virus A, legionella pneumophila, coxiella burnetii and chamydophila pneumonia. Of the 10 435 specimens examined, 7046 tested positive for at least one pathogen. Among all of the tested pathogens, mycoplasma pneumonia had the highest detection rate (56.9%). Influenza virus A and influenza virus B epidemics occurred during both winter and summer. The detection rate of respiratory syncytial virus and adenovirus was higher in spring. Cases of mixed infection were more complex: 4136 specimens (39.6%) tested positive for ≥2 pathogens. There were statistically significant difference in detection rates of mycoplasma pneumonia, influenza virus B, respiratory syncytial virus, parainfluenza virus, adenovirus, influenza virus A, legionella pneumophila and chamydophila pneumonia among different age groups (P acute respiratory infection among children in Hubei of China were mycoplasma pneumonia, influenza virus B and respiratory syncytial virus. The detection rates for each pathogen displayed specific seasonal and age group variations. © 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.

Molecular surveillance of canine distemper virus in diarrhoetic puppies in northeast China from May 2014 to April 2015.

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Li, Chunqiu; Guo, Donghua; Wu, Rui; Kong, Fanzhi; Zhai, Junjun; Yuan, Dongwei; Sun, Dongbo

2018-04-24

To trace the prevalence of canine distemper virus (CDV) in diarrhoetic dogs, a total of 201 stool samples were collected in the Heilongjiang province of northeastern China from May 2014 to April 2015. The 201 fecal samples were subjected to the detection of CDV by using RT-PCR targeting the partial N gene, phylogenetic analysis based on the complete H gene, and co-infection analysis. Results indicated that 24.88% (50/201) of the samples were positive for CDV. The fifty CDV samples exhibited an overall co-infection rate of 94% (47/50) with four enteric viruses (82%, 41/50) and five bacteria (72%, 36/50). The positivity rate of CDV exhibited differences among regions, seasons, ages, and immunization status. Phylogenetic analysis of the complete H genes (n=6) revealed that the CDV strains identified in our study belonged to the Asia-1 group, and showed genetic diversities. These data provide evidence that there are a number of genetically diverse CDV Asia-1 strains circulating in diarrhoetic dogs in northeastern China; the CDV-affected animals exhibit the high co-infection with other enteric viruses and bacteria.

Detection and molecular characterization of J subgroup avian leukosis virus in wild ducks in China.

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Zeng, Xiangwei; Liu, Lanlan; Hao, Ruijun; Han, Chunyan

2014-01-01

To assess the status of avian leukosis virus subgroup J (ALV-J) in wild ducks in China, we examined samples from 528 wild ducks, representing 17 species, which were collected in China over the past 3 years. Virus isolation and PCR showed that 7 ALV-J strains were isolated from wild ducks. The env genes and the 3'UTRs from these isolates were cloned and sequenced. The env genes of all 7 wild duck isolates were significantly different from those in the prototype strain HPRS-103, American strains, broiler ALV-J isolates and Chinese local chicken isolates, but showed close homology with those found in some layer chicken ALV-J isolates and belonged to the same group. The 3'UTRs of 7 ALV-J wild ducks isolates showed close homology with the prototype strain HPRS-103 and no obvious deletion was found in the 3'UTR except for a 1 bp deletion in the E element that introduced a binding site for c-Ets-1. Our study demonstrated the presence of ALV-J in wild ducks and investigated the molecular characterization of ALV-J in wild ducks isolates.

Imported Genotype 2B Rubella Virus Caused the 2012 Outbreak in Anqing City, China.

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Zhen Zhu

Full Text Available A rubella outbreak occurred in Anqing city of Anhui province, China, from February to July of 2012, and a total of 241 clinically diagnosed or lab-confirmed patients were reported. The highest number of rubella cases during this outbreak was recorded in teenagers between 10 and 19 years of age who had not previously received the rubella vaccine. Genotyping results indicated that the genotype 2B rubella virus (RV was responsible for the outbreak. However, a phylogenetic analysis showed that the genotype 2B RVs isolated in Anqing City were not related to 2B RVs found in other cities of Anhui province and in other provinces of China, thus providing evidence for importation. After importation, the transmission of Anqing RVs was interrupted owing to an effective immunization campaign against rubella, suggesting the timeliness and effectiveness of contingency vaccination. Strengthening rubella surveillance, including the integration of epidemiologic information and laboratory data, is a vital strategy for rubella control and elimination. In addition, except for routine immunization, targeted supplementary immunization activities aimed at susceptible groups according to sero-epidemiological surveillance data also play a key role in stopping the continuous transmission of rubella viruses and in preventing further congenital rubella syndrome cases.

Ageratum enation virus-a begomovirus of weeds with the potential to infect crops.

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Tahir, Muhammad; Amin, Imran; Haider, Muhammad Saleem; Mansoor, Shahid; Briddon, Rob W

2015-02-10

Samples of two Ageratum conyzoides, one Sonchus oleraceus and one turnip (Brassica rapa var. rapa) exhibiting virus-like symptoms were collected from Pakistan and Nepal. Full-length begomovirus clones were obtained from the four plant samples and betasatellite clones from three of these. The begomovirus sequences were shown to be isolates of Ageratum enation virus (AEV) with greater than 89.1% nucleotide sequence identity to the 26 AEV sequences available in the databases. The three betasatellite sequences were shown to be isolates of Ageratum yellow leaf curl betasatellite (AYLCB) with greater than 90% identity to the 18 AYLCB sequences available in the databases. The AEV sequences were shown to fall into two distinct strains, for which the names Nepal (consisting of isolates from Nepal, India, and Pakistan-including the isolates identified here) and India (isolates occurring only in India) strains are proposed. For the clones obtained from two AEV isolates, with their AYLCB, infectivity was shown by Agrobacterium-mediated inoculation to Nicotiana benthamiana, N. tabacum, Solanum lycopersicon and A. conyzoides. N. benthamiana plants infected with AEV alone or betasatellite alone showed no symptoms. N. benthamiana plants infected with AEV with its associated betasatellite showed leaf curl symptoms. The findings show that AEV is predominantly a virus of weeds that has the capacity to infect crops. AYLCB appears to be the common partner betasatellite of AEV and is associated with diseases with a range of very different symptoms in the same plant species. The inability to satisfy Koch's postulates with the cloned components of isolate SOL in A. conyzoides suggests that the etiology may be more complex than a single virus with a single betasatellite.

A review of the burden of hepatitis C virus infection in China, Japan, South Korea and Taiwan.

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Bennett, Heather; Waser, Nathalie; Johnston, Karissa; Kao, Jia-Horng; Lim, Young-Suk; Duan, Zhong-Ping; Lee, Youn-Jae; Wei, Lai; Chen, Chien-Jen; Sievert, William; Yuan, Yong; Li, Hong

2015-07-01

Hepatitis C virus (HCV) infection is associated with substantial clinical and economic burden and is an important public health issue in Asia. The objective of this review was to characterize HCV epidemiology and related complications in China, Japan, South Korea and Taiwan. A search of electronic databases and conference abstracts identified 71 potentially relevant articles. Of those, 55 were included in the epidemiology review and 9 in the review of HCV-related complications. HCV prevalence in the general population was 1.6% in China, 0.6-0.9% in Japan, 0.6-1.1% in South Korea and 1.8-5.5% in Taiwan. Prevalence was higher for injecting drug users (48-90%) and those with human immunodeficiency virus coinfection (32-85%) and was lower for blood donors (China was 6.01 per 100,000. HCV genotype 1b was associated with the highest incidence of hepatocellular carcinoma (HCC). Five-year survival for patients with liver cirrhosis was 73.8%, decreasing to 39.2% following liver transplantation; the majority of deaths were attributable to HCC. Limitations were that the majority of studies included in the epidemiology review were small, regional studies conducted in specific populations, and there was an absence of large population-based studies. Thus, estimates may not be representative of the epidemiology of HCV for each country. The prevalence HCV in China and HCV incidence in the Asian region remain largely unknown, and they are likely underestimated. Further epidemiologic and clinical data are needed to provide more precise estimates for use by public health agencies.

Phylogenetic Analysis of Severe Fever with Thrombocytopenia Syndrome Virus in South Korea and Migratory Bird Routes Between China, South Korea, and Japan.

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Yun, Yeojun; Heo, Sang Taek; Kim, Gwanghun; Hewson, Roger; Kim, Hyemin; Park, Dahee; Cho, Nam-Hyuk; Oh, Won Sup; Ryu, Seong Yeol; Kwon, Ki Tae; Medlock, Jolyon M; Lee, Keun Hwa

2015-09-01

Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne viral disease. The SFTS virus (SFTSV) has been detected in the Haemaphysalis longicornis, which acts as a transmission host between animals and humans. SFTSV was first confirmed in China in 2009 and has also been circulating in Japan and South Korea. However, it is not known if a genetic connection exists between the viruses in these regions and, if so, how SFTSV is transmitted across China, South Korea, and Japan. We therefore hypothesize that the SFTSV in South Korea share common phylogenetic origins with samples from China and Japan. Further, we postulate that migratory birds, well-known carriers of the tick H. longicornis, are a potential source of SFTSV transmission across countries. Our phylogenetic analysis results show that the SFTSV isolates in South Korea were similar to isolates from Japan and China. We connect this with previous work showing that SFTSV-infected H. longicornis were found in China, South Korea, and Japan. In addition, H. longicornis were found on migratory birds. The migratory bird routes and the distribution of H. longicornis are concurrent with the occurrence of SFTSV. Therefore, we suggest that migratory birds play an important role in dispersing H. longicornis-borne SFTSV. © The American Society of Tropical Medicine and Hygiene.

Analysis of monthly variability of thermocline in the South China Sea

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Peng, Hanbang; Pan, Aijun; Zheng, Quan'an; Hu, Jianyu

2018-03-01

This study analyzes monthly variability of thermocline and its mechanism in the South China Sea (SCS). The study is based on 51-year (1960-2010) monthly seawater temperature and surface wind stress data from Simple Ocean Data Assimilation (SODA), together with heat flux, precipitation and evaporation data from the National Centers for Environmental Prediction (NCEP), the National Oceanic and Atmospheric Administration (NOAA) and the Woods Hole Oceanographic Institution, respectively. The results reveal that the upper boundary depth ( Z up), lower boundary depth ( Z low), thickness (Δ Z) and intensity ( T z ) of thermocline in the SCS show remarkable monthly variability. Being averaged for the deep basin of SCS, Z up deepens gradually from May to the following January and then shoals from February to May, while Z low varies little throughout the whole year. Further diagnostics indicates that the monthly variability of Z up is mainly caused by the buoyancy flux and wind stress curl. Using a linear method, the impacts of the buoyancy flux and wind stress curl on Z up can be quantitatively distinguished. The results suggest that Z up tends to deepen about 4.6 m when the buoyancy flux increases by 1×10 -5 kg/(m•s 3), while it shoals about 2.5 m when the wind stress curl strengthens by 1×10 -7 N/m³.

Phylogenetic relationships and pathogenicity variation of two Newcastle disease viruses isolated from domestic ducks in Southern China.

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Kang, Yinfeng; Li, Yanling; Yuan, Runyu; Li, Xianwei; Sun, Minhua; Wang, Zhaoxiong; Feng, Minsha; Jiao, Peirong; Ren, Tao

2014-08-12

Newcastle disease (ND) is an OIE listed disease caused by virulent avian paramyxovirus type 1 (APMV-1) strains, which is enzootic and causes large economic losses in the poultry sector. Genotype VII and genotype IX NDV viruses were the predominant circulating genotype in China, which may possibly be responsible for disease outbreaks in chicken flocks in recent years. While ducks and geese usually have exhibited inapparent infections. In the present study, we investigate the complete genome sequence, the clinicopathological characterization and transmission of two virulent Newcastle disease viruses, SS-10 and NH-10, isolated from domestic ducks in Southern China in 2010. F, and the complete gene sequences based on phylogenetic analysis demonstrated that SS-10 (genotype VII) and NH-10 (genotype IX) belongs to class II. The deduced amino acid sequence was (112)R-R-Q-K/R-R-F(117) at the fusion protein cleavage site. Animal experiment results showed that the SS-10 virus isolated from ducks was highly pathogenic for chickens and geese, but low pathogenic for ducks. It could be detected from spleen, lung, kidney, trachea, small intestine, bursa of fabricius, thymus, pancreas and cecal tonsils, oropharyngeal and cloacal swabs, and could transmit to the naive contact birds. Moreover, it could transmit to chickens, ducks and geese by naive contact. However, the NH-10 virus isolated from ducks could infect some chickens, ducks and geese, but only caused chickens to die. Additionally, it could transmit to the naive contact chickens, ducks, and geese. The two NDV isolates exhibited different biological properties with respect to pathogenicity and transmission in chickens, ducks and geese. Therefore, no species-preference exists for chicken, duck or goose viruses and more attention should be paid to the trans-species transmission of VII NDVs between ducks, geese and chickens for the control and eradication of ND.

Molecular characterization of Banana streak virus isolate from Musa Acuminata in China.

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Zhuang, Jun; Wang, Jian-Hua; Zhang, Xin; Liu, Zhi-Xin

2011-12-01

Banana streak virus (BSV), a member of genus Badnavirus, is a causal agent of banana streak disease throughout the world. The genetic diversity of BSVs from different regions of banana plantations has previously been investigated, but there are relatively few reports of the genetic characteristic of episomal (non-integrated) BSV genomes isolated from China. Here, the complete genome, a total of 7722bp (GenBank accession number DQ092436), of an isolate of Banana streak virus (BSV) on cultivar Cavendish (BSAcYNV) in Yunnan, China was determined. The genome organises in the typical manner of badnaviruses. The intergenic region of genomic DNA contains a large stem-loop, which may contribute to the ribosome shift into the following open reading frames (ORFs). The coding region of BSAcYNV consists of three overlapping ORFs, ORF1 with a non-AUG start codon and ORF2 encoding two small proteins are individually involved in viral movement and ORF3 encodes a polyprotein. Besides the complete genome, a defective genome lacking the whole RNA leader region and a majority of ORF1 and which encompasses 6525bp was also isolated and sequenced from this BSV DNA reservoir in infected banana plants. Sequence analyses showed that BSAcYNV has closest similarity in terms of genome organization and the coding assignments with an BSV isolate from Vietnam (BSAcVNV). The corresponding coding regions shared identities of 88% and -95% at nucleotide and amino acid levels, respectively. Phylogenetic analysis also indicated BSAcYNV shared the closest geographical evolutionary relationship to BSAcVNV among sequenced banana streak badnaviruses.

Diversity and Distribution Characteristics of Viruses in Soils of a Marine-Terrestrial Ecotone in East China.

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Yu, Dan-Ting; Han, Li-Li; Zhang, Li-Mei; He, Ji-Zheng

2018-02-01

A substantial gap remains in our understanding of the abundance, diversity, and ecology of viruses in soil although some advances have been achieved in recent years. In this study, four soil samples according to the salinity gradient from shore to inland in East China have been characterized. Results showed that spherical virus particles represented the largest viral component in all of the four samples. The viromes had remarkably different taxonomic compositions, and most of the sequences were derived from single-stranded DNA viruses, especially from families Microviridae and Circoviridae. Compared with viromes from other aquatic and sediment samples, the community compositions of our four soil viromes resembled each other, meanwhile coastal sample virome closely congregated with sediment and hypersaline viromes, and high salinity paddy soil sample virome was similar with surface sediment virome. Phylogenetic analysis of functional genes showed that four viromes have high diversity of the subfamily Gokushovirinae in family Microviridae and most of Circoviridae replicase protein sequences grouped within the CRESS-DNA viruses. This work provided an initial outline of the viral communities in marine-terrestrial ecotone and will improve our understanding of the ecological functions of soil viruses.

Unexpected infection outcomes of China-origin H7N9 low pathogenicity avian influenza virus in turkeys.

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Slomka, Marek J; Seekings, Amanda H; Mahmood, Sahar; Thomas, Saumya; Puranik, Anita; Watson, Samantha; Byrne, Alexander M P; Hicks, Daniel; Nunez, Alejandro; Brown, Ian H; Brookes, Sharon M

2018-05-09

The China-origin H7N9 low pathogenicity avian influenza virus (LPAIV) emerged as a zoonotic threat in 2013 where it continues to circulate in live poultry markets. Absence of overt clinical signs in poultry is a typical LPAIV infection outcome, and has contributed to its insidious maintenance in China. This study is the first description of H7N9 LPAIV (A/Anhui/1/13) infection in turkeys, with efficient transmission to two additional rounds of introduced contact turkeys which all became infected during cohousing. Surprisingly, mortality was observed in six of eight (75%) second-round contact turkeys which is unusual for LPAIV infection, with unexpected systemic dissemination to many organs beyond the respiratory and enteric tracts, but interestingly no accompanying mutation to highly pathogenic AIV. The intravenous pathogenicity index score for a turkey-derived isolate (0.39) affirmed the LPAIV phenotype. However, the amino acid change L235Q in the haemagglutinin gene occurred in directly-infected turkeys and transmitted to the contacts, including those that died and the two which resolved infection to survive to the end of the study. This polymorphism was indicative of a reversion from mammalian to avian adaptation for the H7N9 virus. This study underlined a new risk to poultry in the event of H7N9 spread beyond China.

Field Trial and Molecular Characterization of RNAi-Transgenic Tomato Plants That Exhibit Resistance to Tomato Yellow Leaf Curl Geminivirus.

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Fuentes, Alejandro; Carlos, Natacha; Ruiz, Yoslaine; Callard, Danay; Sánchez, Yadira; Ochagavía, María Elena; Seguin, Jonathan; Malpica-López, Nachelli; Hohn, Thomas; Lecca, Maria Rita; Pérez, Rosabel; Doreste, Vivian; Rehrauer, Hubert; Farinelli, Laurent; Pujol, Merardo; Pooggin, Mikhail M

2016-03-01

RNA interference (RNAi) is a widely used approach to generate virus-resistant transgenic crops. However, issues of agricultural importance like the long-term durability of RNAi-mediated resistance under field conditions and the potential side effects provoked in the plant by the stable RNAi expression remain poorly investigated. Here, we performed field trials and molecular characterization studies of two homozygous transgenic tomato lines, with different selection markers, expressing an intron-hairpin RNA cognate to the Tomato yellow leaf curl virus (TYLCV) C1 gene. The tested F6 and F4 progenies of the respective kanamycin- and basta-resistant plants exhibited unchanged field resistance to TYLCV and stably expressed the transgene-derived short interfering RNA (siRNAs) to represent 6 to 8% of the total plant small RNAs. This value outnumbered the average percentage of viral siRNAs in the nontransformed plants exposed to TYLCV-infested whiteflies. As a result of the RNAi transgene expression, a common set of up- and downregulated genes was revealed in the transcriptome profile of the plants selected from either of the two transgenic events. A previously unidentified geminivirus causing no symptoms of viral disease was detected in some of the transgenic plants. The novel virus acquired V1 and V2 genes from TYLCV and C1, C2, C3, and C4 genes from a distantly related geminivirus and, thereby, it could evade the repressive sequence-specific action of transgene-derived siRNAs. Our findings shed light on the mechanisms of siRNA-directed antiviral silencing in transgenic plants and highlight the applicability limitations of this technology as it may alter the transcriptional pattern of nontarget genes.

The genomic and biological characterization of Citrullus lanatus cryptic virus infecting watermelon in China.

Science.gov (United States)

Xin, Min; Cao, Mengji; Liu, Wenwen; Ren, Yingdang; Lu, Chuantao; Wang, Xifeng

2017-03-15

A dsRNA virus was detected in the watermelon (Citrullus lanatus) samples collected from Kaifeng, Henan province, China through the use of next generation sequencing of small RNAs. The complete genome of this virus is comprised of dsRNA-1 (1603nt) and dsRNA-2 (1466nt), both of which are single open reading frames and potentially encode a 54.2kDa RNA-dependent RNA polymerase (RdRp) and a 45.9kDa coat protein (CP), respectively. The RdRp and CP share the highest amino acid identities 85.3% and 75.4% with a previously reported Israeli strain Citrullus lanatus cryptic virus (CiLCV), respectively. Genome comparisons indicate that this virus is the same species with CiLCV, whereas the reported sequences of the Israeli strain of CiLCV are partial, and our newly identified sequences can represent the complete genome of CiLCV. Futhermore, phylogenetic tree analyses based on the RdRp sequences suggest that CiLCV is one member in the genus Deltapartitivirus, family Partitiviridae. In addition, field investigation and seed-borne bioassays show that CiLCV commonly occurs in many varieties and is transmitted though seeds at a very high rate. Copyright © 2017 Elsevier B.V. All rights reserved.

The neglected arboviral infections in mainland China.

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Xiaoyan Gao

2010-04-01

Full Text Available The major arboviral diseases in mainland China include Japanese encephalitis, dengue fever, Crimean-Congo hemorrhagic fever (also known as Xinjiang hemorrhagic fever, and tick-borne encephalitis. These and other newly found arbovirus infections due to Banna virus and Tahyna virus contribute to a large and relatively neglected disease burden in China. Here we briefly review the literature regarding these arboviral infections in mainland China with emphasis on their epidemiology, primary vectors, phylogenetic associations, and the prevention programs associated with these agents in China.

Molecular characterization of a novel reassortant H1N2 influenza virus containing genes from the 2009 pandemic human H1N1 virus in swine from eastern China.

Science.gov (United States)

Peng, Xiuming; Wu, Haibo; Xu, Lihua; Peng, Xiaorong; Cheng, Linfang; Jin, Changzhong; Xie, Tiansheng; Lu, Xiangyun; Wu, Nanping

2016-06-01

Pandemic outbreaks of H1N1 swine influenza virus have been reported since 2009. Reassortant H1N2 viruses that contain genes from the pandemic H1N1 virus have been isolated in Italy and the United States. However, there is limited information regarding the molecular characteristics of reassortant H1N2 swine influenza viruses in eastern China. Active influenza surveillance programs in Zhejiang Province identified a novel H1N2 influenza virus isolated from pigs displaying clinical signs of influenza virus infection. Whole-genome sequencing was performed and this strain was compared with other influenza viruses available in GenBank. Phylogenetic analysis suggested that the novel strain contained genes from the 2009 pandemic human H1N1 and swine H3N2 viruses. BALB/c mice were infected with the isolated virus to assess its virulence in mice. While the novel H1N2 isolate replicated well in mice, it was found to be less virulent. These results provide additional evidence that swine serve as intermediate hosts or 'mixing vessels' for novel influenza viruses. They also emphasize the importance of surveillance in the swine population for use as an early warning system for influenza outbreaks in swine and human populations.

Xanthium strumarium: a weed host of components of begomovirus-betasatellite complexes affecting crops.

Science.gov (United States)

Mubin, M; Akhtar, S; Amin, I; Briddon, R W; Mansoor, S

2012-02-01

Xanthium strumarium is a common weed that often shows symptoms typical of begomovirus infection, such as leaf curling and vein thickening. The virus complex isolated from the weed consisted of two begomoviruses along with a betasatellite and an alphasatellite. The first begomovirus was shown to be an isolate of Cotton leaf curl Burewala virus, a new recombinant begomovirus species that is associated with resistance breaking in previously resistant cotton varieties in Pakistan, whereas the second was shown to be an isolate of Tomato leaf curl Gujarat virus (ToLCGV), a begomovirus previously reported to be bipartite. However, there was no evidence for the presence of the second genomic component, DNA B, of ToLCGV in X. strumarium. The betasatellite was shown to be an isolate of Tomato yellow leaf curl Thailand betasatellite, the first time this satellite has been identified in Pakistan. The alphasatellite associated with infection of X. strumarium was shown to be a species recently identified in potato and various weeds; Potato leaf curl alphasatellite. Although each component has been identified previously, this is the first time they have been identified in a single host. These findings reinforce the hypothesis that weeds are reservoirs of crop-infecting begomoviruses that may contribute to virus diversity by virtue of harboring multiple viruses and virus associated components, which may lead to interspecific recombination and component exchange.

Zika virus infection in travelers returning from countries with local transmission, Guangdong, China, 2016.

Science.gov (United States)

Jia, Haimei; Zhang, Meng; Chen, Maoyu; Yang, Zhiwen; Li, Jiansen; Huang, Guo; Guan, Dawei; Cen, Xiaoli; Zhang, Lijie; Feng, Qiwen; Yi, Jianron; Wu, De; Zhong, Haojie; Ma, Huilai; Song, Tie

Zika virus (ZIKV) is a mosquito-borne virus spreading rapidly in the Americas, Africa, and Asia. No indigenous ZIKV infection had been seen in China. We monitored ZIKV infection among travelers returning to Enping county from ZIKV transmitting countries from 1 March to 10 April 2016. We analyzed data including interviews; conducted laboratory test on blood, urine, saliva, conjunctival swab or semen specimens for evidence of ZIKV infection; evaluated household for presence of Aedes mosquitoes or larvae. A total of 925 individuals were screened, 507 (54.8%) were interviewed, 400 (43.2%) provided samples, of which 13 (3.3%) tested positive for ZIKV including 3 asymptomatic. Rash, conjunctivitis, sore throat, fever were the common symptoms; rash was more pronounced in adults than in children. ZIKV RNA was detected for 1-4 days in blood, but longer in urine and saliva (3-32 days and 2-10 days). Among interviewed, 57.0% had good knowledge about ZIKV, 45.8% were worried about ZIKV, 99.2% would go to hospital if they had infection. Aedes mosquitoes or larvae were detected in townships of infected returners. ZIKV was imported to China. Screening by symptoms alone is inadequate for detecting ZIKV infection. ZIKV surveillance, health-education, and vector control are necessary to decrease risk of ZIKV transmission. Copyright © 2017. Published by Elsevier Ltd.

Direct measurement of conformational strain energy in protofilaments curling outward from disassembling microtubule tips.

Science.gov (United States)

Driver, Jonathan W; Geyer, Elisabeth A; Bailey, Megan E; Rice, Luke M; Asbury, Charles L

2017-06-19

Disassembling microtubules can generate movement independently of motor enzymes, especially at kinetochores where they drive chromosome motility. A popular explanation is the 'conformational wave' model, in which protofilaments pull on the kinetochore as they curl outward from a disassembling tip. But whether protofilaments can work efficiently via this spring-like mechanism has been unclear. By modifying a previous assay to use recombinant tubulin and feedback-controlled laser trapping, we directly demonstrate the spring-like elasticity of curling protofilaments. Measuring their mechanical work output suggests they carry ~25% of the energy of GTP hydrolysis as bending strain, enabling them to drive movement with efficiency similar to conventional motors. Surprisingly, a β-tubulin mutant that dramatically slows disassembly has no effect on work output, indicating an uncoupling of disassembly speed from protofilament strain. These results show the wave mechanism can make a major contribution to kinetochore motility and establish a direct approach for measuring tubulin mechano-chemistry.

Genetic and antigenic evolution of H9N2 subtype avian influenza virus in domestic chickens in southwestern China, 2013-2016.

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Jing Xia

Full Text Available H9N2 avian influenza virus (AIV has caused significant losses in chicken flocks throughout china in recent years. There is a limited understanding of the genetic and antigenic characteristics of the H9N2 virus isolated in chickens in southwestern China. In this study a total of 12 field strains were isolated from tissue samples from diseased chickens between 2013 and 2016. Phylogenetic analysis of the Hemagglutinin (HA and Neuraminidase (NA nucleotide sequences from the 12 field isolates and other reference strains showed that most of the isolates in the past four years could be clustered into a major branch (HA-branch A and NA-branch I in the Clade h9.4.2 lineages. These sequences are accompanied by nine and seven new amino acids mutations in the HA and NA proteins, respectively, when compared with those previous to 2013. In addition, four new isolates were grouped into a minor branch (HA-branch B in the Clade h9.4.2 lineages and two potential N-glycosylation sites were observed due to amino acid mutations in the HA protein. Three antigenic groups (1-3, which had low antigenic relatedness with two commonly used vaccines in China, were identified among the 12 isolates by antigenMap analysis. Immunoprotection testing showed that those two vaccines could efficiently prevent the shedding of branch A viruses but not branch B viruses. In conclusion, these results indicate the genotype of branch B may become epidemic in the next few years and that a new vaccine should be developed for the prevention of H9N2 AIV.

Transcriptomics of the interaction between the monopartite phloem-limited geminivirus tomato yellow leaf curl Sardinia virus and Solanum lycopersicum highlights a role for plant hormones, autophagy and plant immune system fine tuning during infection.

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Laura Miozzi

Full Text Available Tomato yellow leaf curl Sardinia virus (TYLCSV, a DNA virus belonging to the genus Begomovirus, causes severe losses in tomato crops. It infects only a limited number of cells in the vascular tissues, making difficult to detect changes in host gene expression linked to its presence. Here we present the first microarray study of transcriptional changes induced by the phloem-limited geminivirus TYLCSV infecting tomato, its natural host. The analysis was performed on the midrib of mature leaves, a material naturally enriched in vascular tissues. A total of 2206 genes were up-regulated and 1398 were down-regulated in infected plants, with an overrepresentation of genes involved in hormone metabolism and responses, nucleic acid metabolism, regulation of transcription, ubiquitin-proteasome pathway and autophagy among those up-regulated, and in primary and secondary metabolism, phosphorylation, transcription and methylation-dependent chromatin silencing among those down-regulated. Our analysis showed a series of responses, such as the induction of GA- and ABA-responsive genes, the activation of the autophagic process and the fine tuning of the plant immune system, observed only in TYLCSV-tomato compatible interaction so far. On the other hand, comparisons with transcriptional changes observed in other geminivirus-plant interactions highlighted common host responses consisting in the deregulation of biotic stress responsive genes, key enzymes in the ethylene biosynthesis and methylation cycle, components of the ubiquitin proteasome system and DNA polymerases II. The involvement of conserved miRNAs and of solanaceous- and tomato-specific miRNAs in geminivirus infection, investigated by integrating differential gene expression data with miRNA targeting data, is discussed.

Generation and Characterization of HIV-1 Transmitted and Founder Virus Consensus Sequence from Intravenous Drug Users in Xinjiang, China.

Science.gov (United States)

Li, Fan; Ma, Liying; Feng, Yi; Hu, Jing; Ni, Na; Ruan, Yuhua; Shao, Yiming

2017-06-01

HIV-1 transmission in intravenous drug users (IDUs) has been characterized by high genetic multiplicity and suggests a greater challenge for HIV-1 infection blocking. We investigated a total of 749 sequences of full-length gp160 gene obtained by single genome sequencing (SGS) from 22 HIV-1 early infected IDUs in Xinjiang province, northwest China, and generated a transmitted and founder virus (T/F virus) consensus sequence (IDU.CON). The T/F virus was classified as subtype CRF07_BC and predicted to be CCR5-tropic virus. The variable region (V1, V2, and V4 loop) of IDU.CON showed length variation compared with the heterosexual T/F virus consensus sequence (HSX.CON) and homosexual T/F virus consensus sequence (MSM.CON). A total of 26 N-linked glycosylation sites were discovered in the IDU.CON sequence, which is less than that of MSM.CON and HSX.CON. Characterization of T/F virus from IDUs highlights the genetic make-up and complexity of virus near the moment of transmission or in early infection preceding systemic dissemination and is important toward the development of an effective HIV-1 preventive methods, including vaccines.

Primary surveys on molecular epidemiology of bovine viral diarrhea virus 1 infecting goats in Jiangsu province, China.

Science.gov (United States)

Mao, Li; Li, Wenliang; Yang, Leilei; Wang, Jianhui; Cheng, Suping; Wei, Yong; Wang, Qiusheng; Zhang, Wenwen; Hao, Fei; Ding, Yonglong; Sun, Yinhua; Jiang, Jieyuan

2016-09-05

Bovine viral diarrhea virus (BVDV) is a pathogen of domestic and wildlife animals worldwide and is associated with several diseases. In China, there are many reports about genotyping of BVDV strains originated from cattle and pigs, and some of them focused on the geographical distributions of BVDV. Currently, the goat industry in Jiangsu province of China is under going a rapid expansion. Most of these goat farms are backyard enterprises and in close proximity to pig and cattle farms. However, there was very limited information about BVDV infections in goats. The objective of this study was to assess the frequency of BVDV infections of goats, the relationship of these infections to clinical signs and determine what BVDV genotypes are circulating in Jiangsu province. From 236 goat sera collected from six regions in Jiangsu province between 2011 and 2013, BVDV-1 was identified in 29 samples from the five regions by RT-PCR. The BVDV-1 infections occurred with/without clinical signs. Eight different BVDV-1 strains were identified from these positive samples based on the 5'-untranslated region (5'-UTR) sequences, and further clustered into four BVDV-1 subtypes on the phylogenetic analysis. Three were BVDV-1b, two BVDV-1m, two BVDV-1o, and one BVDV-1p, respectively. To our knowledge, this is the first report to investigate the occurrence of BVDV and the genotypes of BVDV infecting goats in China. The results indicated that BVDV-1 infections were indeed present and the viruses were with genetic variations in Chinese goat herds. The information would be very useful for prevention and control of BVDV-1 infections in China.

Comparison of the prevalence of respiratory viruses in patients with acute respiratory infections at different hospital settings in North China, 2012-2015.

Science.gov (United States)

Yu, Jianxing; Xie, Zhengde; Zhang, Tiegang; Lu, Yanqin; Fan, Hongwei; Yang, Donghong; Bénet, Thomas; Vanhems, Philippe; Shen, Kunling; Huang, Fang; Han, Jinxiang; Li, Taisheng; Gao, Zhancheng; Ren, Lili; Wang, Jianwei

2018-02-08

Acute respiratory infections (ARIs) are a great public health challenge globally. The prevalence of respiratory viruses in patients with ARIs attending at different hospital settings is fully undetermined. Laboratory-based surveillance for ARIs was conducted at inpatient and outpatient settings of 11 hospitals in North China. The first 2-5 patients with ARIs were recruited in each hospital weekly from 2012 through 2015. The presence of respiratory viruses was screened by PCR assays. The prevalence of respiratory viruses was determined and compared between patients at different hospital settings. A total of 3487 hospitalized cases and 6437 outpatients/Emergency Department (ED) patients were enrolled. The most commonly detected viruses in the hospitalized cases were respiratory syncytial virus (RSV, 33.3%) in children less than two years old, adenoviruses (13.0%) in patients 15-34 years old, and influenza viruses (IFVs, 9.6%) in patients ≥65 years. IFVs were the most common virus in outpatient/ED patients across all age groups (22.7%). After controlling for the confounders caused by other viruses and covariates, adenoviruses (adjusted odds ratio [aOR]: 3.97, 99% confidence interval [99% CI]: 2.19-7.20) and RSV (aOR: 2.04, 99% CI: 1.34-3.11) were independently associated with increased hospitalization in children, as well as adenoviruses in adults (aOR: 2.14, 99% CI: 1.19-3.85). Additionally, co-infection of RSV with IFVs was associated with increased hospitalization in children (aOR: 12.20, 99% CI: 2.65-56.18). A substantial proportion of ARIs was associated with respiratory viruses in North China. RSV, adenoviruses, and co-infection of RSV and IFVs were more frequent in hospitalized children (or adenoviruses in adults), which might predict the severity of ARIs. Attending clinicians should be more vigilant of these infections.

Screening for sweet potato (Ipomoea batatas (L.)) viruses and their elimination using thermotheraphy-meristem tip culture technique

International Nuclear Information System (INIS)

Arkorful, E.

2012-11-01

Despite its high potential for food security, production of sweet potato is constrained by viruses which reduce yield by 90%. It is therefore essential to screen for, identify and eliminate these viruses in elite clones before dissemination to farmers. In this study, visual symptomatology and PCR-based techniques were used to identify sweet potato viruses. Visual symptomatology revealed virus associated symptoms ranging from vein clearing, interveinal chlorosis, chlorotic spots, upward curling on leaf edges, leaf narrowing and distortion, purpling, blistering, reduction of the leaf blades and general leaf yellowing in all 22 accessions grown on the field. Disease Incidence (DI) significantly (p≤0.05) varied between accessions with US003 having the lowest (20%) while ten accessions had 90% DI at the end of the study. Index of symptom severity of all plants (ISSap) ranged from 1.08±0.09 to 3.67 ±0.11 with VOTCR003 having the lowest suggesting that it is a moderately susceptible accession while VOTCR002 had the highest suggesting that it is susceptible to viral diseases. Contrarily, index of symptom severity of diseased plants (ISSdp) ranged from 2.00±0.25 to 3.75±0.32. The accession VOTCR002 had the highest ISSdp. Visual symptomatology showed that VOTCR002 had the highest DI, ISSap and ISSdp suggesting that it is highly susceptible to viral diseases. Ten severely infected accessions were tested for Sweet Potato leaf curl virus (SPLCV), Sweet Potato chlorotic stunt virus (SPCSV), Sweet potato feathery mottle virus (SPFMV) and Sweet Potato mild mottle virus (SPMMV) using PCR and RT-PCR techniques. RT-PCR did not amplify any of the virus genomes due to prolonged storage enzymes, In contrast, PCR detected SPLCV in 30% of the accessions. Plants infected with SPLCV were grown in the chamber at 35 degrees celsius for 4 weeks followed by meristem top culture. The regenerants were indexed after ten weeks for SPLCV. Fifty two percent (52.385 od the regenerants were

Molecular characterization of a naturally occurring intraspecific recombinant begomovirus with close relatives widespread in southern Arabia

KAUST Repository

Al-Saleh, Mohammed A; Al-Shahwan, Ibrahim M; Brown, Judith K; Idris, Ali

2014-01-01

Background: Tomato leaf curl Sudan virus (ToLCSDV) is a single-stranded DNA begomovirus of tomato that causes downward leaf curl, yellowing, and stunting. Leaf curl disease results in significant yield reduction in tomato crops in the Nile Basin. To

Could Changes in the Agricultural Landscape of Northeastern China Have Influenced the Long-Distance Transmission of Highly Pathogenic Avian Influenza H5Nx Viruses?

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Marius Gilbert

2017-12-01

Full Text Available In the last few years, several reassortant subtypes of highly pathogenic avian influenza viruses (HPAI H5Nx have emerged in East Asia. These new viruses, mostly of subtype H5N1, H5N2, H5N6, and H5N8 belonging to clade 2.3.4.4, have been found in several Asian countries and have caused outbreaks in poultry in China, South Korea, and Vietnam. HPAI H5Nx also have spread over considerable distances with the introduction of viruses belonging to the same 2.3.4.4 clade in the U.S. (2014–2015 and in Europe (2014–2015 and 2016–2017. In this paper, we examine the emergence and spread of these new viruses in Asia in relation to published datasets on HPAI H5Nx distribution, movement of migratory waterfowl, avian influenza risk models, and land-use change analyses. More specifically, we show that between 2000 and 2015, vast areas of northeast China have been newly planted with rice paddy fields (3.21 million ha in Heilongjiang, Jilin, and Liaoning in areas connected to other parts of Asia through migratory pathways of wild waterfowl. We hypothesize that recent land use changes in northeast China have affected the spatial distribution of wild waterfowl, their stopover areas, and the wild-domestic interface, thereby altering transmission dynamics of avian influenza viruses across flyways. Detailed studies of the habitat use by wild migratory birds, of the extent of the wild–domestic interface, and of the circulation of avian influenza viruses in those new planted areas may help to shed more light on this hypothesis, and on the possible impact of those changes on the long-distance patterns of avian influenza transmission.

Physical control possibilities of Bemisia tabaci (Gennadius) and Tomato yellow leaf curl disease (TYLCD) in protected crops

International Nuclear Information System (INIS)

Rapisarda, C.; Cascone, G.; Tropea Garzia, G.; Mazzarella, R.; Colombo, A.; Serges, T.

2005-01-01

Among alternatives to chemical control for reducing virus epidemics in protected tomato crops, physical management of vectors populations through the application of insect-proof screens to greenhouse openings has been investigated since many years and satisfactory results have been obtained so far, especially regarding the incidence of the whitefly Bemisia tabaci (Gennadius), which is the vector of Tomato yellow leaf curl disease (TYLCD). Nevertheless, although effective from the phytosanitary point of view, these insect-proof screens negatively affect the climate inside the greenhouse, by reducing ventilation, increasing air temperature, etc.. Recently, a low incidence of whitefly infestations on crops has been observed inside greenhouses which have been covered with photoselective plastic films absorbing the ultra-violet component (200-380 nm) of solar radiation. The present study, carried out in Sicily by means of three trials during three consecutive years, allowed to evaluate the ability of two different UV-absorbing plastic films to reduce B. tabaci infestations, in comparison to UV-unabsorbing plastic films and insect-proof screens commonly used to cover and protect tomato greenhouses. The results show the good efficiency of both the tested UV-absorbing films to reduce the witefly presence on tomato crops and the consequent TYLCD spreading. Furthermore, it may be observed that UV-absorbing films do not determine sensible variations of greenhouse climate conditions, compared to greenhouses covered with conventional films. These data not only confirm the physical validity of the UV-absorbing films, but also show that they may fit properly within strategies of integrated control of pests and viruses in protected cultivations [it

Epidemiological surveillance of low pathogenic avian influenza virus (LPAIV from poultry in Guangxi Province, Southern China.

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Yi Peng

Full Text Available Low pathogenic avian influenza virus (LPAIV usually causes mild disease or asymptomatic infection in poultry. However, some LPAIV strains can be transmitted to humans and cause severe infection. Genetic rearrangement and recombination of even low pathogenic influenza may generate a novel virus with increased virulence, posing a substantial risk to public health. Southern China is regarded as the world "influenza epicenter", due to a rash of outbreaks of influenza in recent years. In this study, we conducted an epidemiological survey of LPAIV at different live bird markets (LBMs in Guangxi province, Southern China. From January 2009 to December 2011, we collected 3,121 cotton swab samples of larynx, trachea and cloaca from the poultry at LBMs in Guangxi. Virus isolation, hemagglutination inhibition (HI assay, and RT-PCR were used to detect and subtype LPAIV in the collected samples. Of the 3,121 samples, 336 samples (10.8% were LPAIV positive, including 54 (1.7% in chicken and 282 (9.1% in duck. The identified LPAIV were H3N1, H3N2, H6N1, H6N2, H6N5, H6N6, H6N8, and H9N2, which are combinations of seven HA subtypes (H1, H3, H4, H6, H9, H10 and H11 and five NA subtypes (N1, N2, N5, N6 and N8. The H3 and H9 subtypes are predominant in the identified LPAIVs. Among the 336 cases, 29 types of mixed infection of different HA subtypes were identified in 87 of the cases (25.9%. The mixed infections may provide opportunities for genetic recombination. Our results suggest that the LPAIV epidemiology in poultry in the Guangxi province in southern China is complicated and highlights the need for further epidemiological and genetic studies of LPAIV in this area.

Analysis of factors that influence the maximum number of repetitions in two upper-body resistance exercises: curl biceps and bench press.

Science.gov (United States)

Iglesias, Eliseo; Boullosa, Daniel A; Dopico, Xurxo; Carballeira, Eduardo

2010-06-01

The purpose of this study was to analyze the influence of exercise type, set configuration, and relative intensity load on relationship between 1 repetition maximum (1RM) and maximum number of repetitions (MNR). Thirteen male subjects, experienced in resistance training, were tested in bench press and biceps curl for 1RM, MNR at 90% of 1RM with cluster set configuration (rest of 30s between repetitions) and MNR at 70% of 1RM with traditional set configuration (no rest between repetitions). A lineal encoder was used for measuring displacement of load. Analysis of variance analysis revealed a significant effect of load (pbench press and biceps curl, respectively; pbench press and biceps curl, respectively; p>0.05). Correlation between 1RM and MNR was significant for medium-intensity in biceps curl (r=-0.574; pvelocity along set, so velocity seems to be similar at a same relative intensity for subjects with differences in maximum strength levels. From our results, we suggest the employment of MNR rather than % of 1RM for training monitoring. Furthermore, we suggest the introduction of cluster set configuration for upper-body assessment of MNR and for upper-body muscular endurance training at high-intensity loads, as it seems an efficient approach in looking for sessions with greater training volumes. This could be an interesting approach for such sports as wrestling or weightlifting.

Highly Pathogenic Avian Influenza A(H5N1) Virus Struck Migratory Birds in China in 2015.

Science.gov (United States)

Bi, Yuhai; Zhang, Zhenjie; Liu, Wenjun; Yin, Yanbo; Hong, Jianmin; Li, Xiangdong; Wang, Haiming; Wong, Gary; Chen, Jianjun; Li, Yunfeng; Ru, Wendong; Gao, Ruyi; Liu, Di; Liu, Yingxia; Zhou, Boping; Gao, George F; Shi, Weifeng; Lei, Fumin

2015-08-11

Approximately 100 migratory birds, including whooper swans and pochards, were found dead in the Sanmenxia Reservoir Area of China during January 2015. The causative agent behind this outbreak was identified as H5N1 highly pathogenic avian influenza virus (HPAIV). Genetic and phylogenetic analyses revealed that this Sanmenxia H5N1 virus was a novel reassortant, possessing a Clade 2.3.2.1c HA gene and a H9N2-derived PB2 gene. Sanmenxia Clade 2.3.2.1c-like H5N1 viruses possess the closest genetic identity to A/Alberta/01/2014 (H5N1), which recently caused a fatal respiratory infection in Canada with signs of meningoencephalitis, a highly unusual symptom with influenza infections in humans. Furthermore, this virus was shown to be highly pathogenic to both birds and mammals, and demonstrate tropism for the nervous system. Due to the geographical location of Sanmenxia, these novel H5N1 viruses also have the potential to be imported to other regions through the migration of wild birds, similar to the H5N1 outbreak amongst migratory birds in Qinghai Lake during 2005. Therefore, further investigation and monitoring is required to prevent this novel reassortant virus from becoming a new threat to public health.

Epidemiology, Evolution, and Pathogenesis of H7N9 Influenza Viruses in Five Epidemic Waves since 2013 in China.

Science.gov (United States)

Su, Shuo; Gu, Min; Liu, Di; Cui, Jie; Gao, George F; Zhou, Jiyong; Liu, Xiufan

2017-09-01

H7N9 influenza viruses were first isolated in 2013 and continue to cause human infections. H7N9 infections represent an ongoing public health threat that has resulted in 1344 cases with 511 deaths as of April 9, 2017. This highlights the continued threat posed by the current poultry trade and live poultry market system in China. Until now, there have been five H7N9 influenza epidemic waves in China; however, the steep increase in the number of humans infected with H7N9 viruses observed in the fifth wave, beginning in October 2016, the spread into western provinces, and the emergence of highly pathogenic (HP) H7N9 influenza outbreaks in chickens and infection in humans have caused domestic and international concern. In this review, we summarize and compare the different waves of H7N9 regarding their epidemiology, pathogenesis, evolution, and characteristic features, and speculate on factors behind the recent increase in the number of human cases and sudden outbreaks in chickens. The continuous evolution of the virus poses a long-term threat to public health and the poultry industry, and thus it is imperative to strengthen prevention and control strategies. Copyright © 2017. Published by Elsevier Ltd.

The genetic structure of Turnip mosaic virus population reveals the rapid expansion of a new emergent lineage in China.

Science.gov (United States)

Li, Xiangdong; Zhu, Tiansheng; Yin, Xiao; Zhang, Chengling; Chen, Jia; Tian, Yanping; Liu, Jinliang

2017-08-29

Turnip mosaic virus (TuMV) is one of the most widespread and economically important virus infecting both crop and ornamental species of the family Brassicaceae. TuMV isolates can be classified to five phylogenetic lineages, basal-B, basal-BR, Asian-BR, world-B and Orchis. To understand the genetic structure of TuMV from radish in China, the 3'-terminal genome of 90 TuMV isolates were determined and analyzed with other available Chinese isolates. The results showed that the Chinese TuMV isolates from radish formed three groups: Asian-BR, basal-BR and world-B. More than half of these isolates (52.54%) were clustered to basal-BR group, and could be further divided into three sub-groups. The TuMV basal-BR isolates in the sub-groups I and II were genetically homologous with Japanese ones, while those in sub-group III formed a distinct lineage. Sub-populations of TuMV basal-BR II and III were new emergent and in a state of expansion. The Chinese TuMV radish populations were under negative selection. Gene flow between TuMV populations from Tai'an, Weifang and Changchun was frequent. The genetic structure of Turnip mosaic virus population reveals the rapid expansion of a new emergent lineage in China.

A weak Galerkin least-squares finite element method for div-curl systems

Science.gov (United States)

Li, Jichun; Ye, Xiu; Zhang, Shangyou

2018-06-01

In this paper, we introduce a weak Galerkin least-squares method for solving div-curl problem. This finite element method leads to a symmetric positive definite system and has the flexibility to work with general meshes such as hybrid mesh, polytopal mesh and mesh with hanging nodes. Error estimates of the finite element solution are derived. The numerical examples demonstrate the robustness and flexibility of the proposed method.

Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections in stray and pet cats (Felis catus) in northwest China: co-infections and risk factors.

Science.gov (United States)

Cong, Wei; Meng, Qing-Feng; Blaga, Radu; Villena, Isabelle; Zhu, Xing-Quan; Qian, Ai-Dong

2016-01-01

This study was conducted to estimate the prevalence of Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections among stray and pet cats in Lanzhou, northwest China, and to identify the influence of age, gender, and regions on seropositivity. T. gondii antibodies were examined in cat sera by the modified agglutination test (MAT). The circulating antigens of D. immitis and FeLV and specific antibodies to FIV were examined using kits commercially available. The overall prevalence of T. gondii, FIV, FeLV, and D. immitis was 19.34, 9.12, 11.33, and 3.04 %, respectively. For the genetic characterization of T. gondii genotypes in cats, genomic DNA was extracted from the seropositive cats and the T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genotyped using multilocus PCR-RFLP. Two T. gondii genotypes (ToxoDB#9 and ToxoDB#1) were identified. Results of the multivariate logistic regression analysis showed that older cats are more likely to be seropositive than juveniles for T. gondii, FIV, FeLV, and D. immitis. This is the first report of T. gondii genotypes in cats in northwest China. Moreover, the present study is the first study of retrovirus and D. immitis seroprevalence in cats in China. The results revealed that T. gondii, FIV, and FeLV infections are common in stray and pet cats in northwest China.

Novel coronaviruses, astroviruses, adenoviruses and circoviruses in insectivorous bats from northern China.

Science.gov (United States)

Han, H-J; Wen, H-L; Zhao, L; Liu, J-W; Luo, L-M; Zhou, C-M; Qin, X-R; Zhu, Y-L; Liu, M-M; Qi, R; Li, W-Q; Yu, H; Yu, X-J

2017-12-01

Bats are considered as the reservoirs of several emerging infectious disease, and novel viruses are continually found in bats all around the world. Studies conducted in southern China found that bats carried a variety of viruses. However, few studies have been conducted on bats in northern China, which harbours a diversity of endemic insectivorous bats. It is important to understand the prevalence and diversity of viruses circulating in bats in northern China. In this study, a total of 145 insectivorous bats representing six species were collected from northern China and screened with degenerate primers for viruses belonging to six families, including coronaviruses, astroviruses, hantaviruses, paramyxoviruses, adenoviruses and circoviruses. Our study found that four of the viruses screened for were positive and the overall detection rates for astroviruses, coronaviruses, adenoviruses and circoviruses in bats were 21.4%, 15.9%, 20% and 37.2%, respectively. In addition, we found that bats in northern China harboured a diversity of novel viruses. Common Serotine (Eptesicus serotinu), Fringed long-footed Myotis (Myotis fimriatus) and Peking Myotis (Myotis pequinius) were investigated in China for the first time. Our study provided new information on the ecology and phylogeny of bat-borne viruses. © 2017 The Authors. Zoonoses and Public Health Published by Blackwell Verlag GmbH.

Short communication. First report of Eggplant mottled dwarf virus in China rose in southern Spain

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G. Parrella

2013-01-01

Full Text Available Eggplant mottled dwarf virus (EMDV, genus Nucleorhabdovirus, family Rhabdoviridae is transmitted in nature by leafhoppers and its natural host range includes vegetable crops (eggplant, tomato, potato, pepper, ornamentals (pittosporum, honeysuckle, pelargonium and wild plants (caper, Solanum nigrum. The prevalence of infections is generally very low. EMDV has been demonstrated to be the causal agent of a vein yellowing disease of China rose (Hibiscus rosa-sinensis in southern Italy. In this work, four locations from Málaga and Granada provinces (southern Spain were surveyed in 2011 to study the prevalence of EMDV infections in China rose by serological and molecular methods. Overall, EMDV was detected in 77.3% of the samples (33 out of 45 samples tested. Mechanical transmission tests and immunoelectron microscopy confirmed the presence of EMDV. The possible causes of such a high and unexpected prevalence are discussed. The use of molecular hibridization with an EMDV specific riboprobe is proposed for early screening of vegetative propagated China rose plants to avoid dissemination of infected material.

Hepatitis E Virus Genotype 4 Sequences Detected in Sewage from Treatment Plants of China

OpenAIRE

Li, Heng; Li, Wei; She, Ruiping; Yu, Liang; Wu, Qiaoxing; Yang, Jingling; Hu, Fengjiao; Soomro, Majid Hussain; Shi, Ruihan; Hao, Wenzhuo; Zhao, Yue; Mao, Jingjing

2017-01-01

The aim of this study was to investigate the occurrence of hepatitis E virus (HEV) in sewage samples in Shen Zhen, China. Sewage samples were collected from 152 sewage plants including livestock sewage, domestic sewage and treated sewage from May to July of 2015. Two of 152 samples were HEV positive (1.32%) from the livestock sewage plants. Partial ORF2 fragments of HEV were sequenced and a phylogenetic tree was constructed using MEGA5.1. Blast and phylogenetic analyses showed that both of th...

Wind stress, curl and vertical velocity in the Bay of Bengal during southwest monsoon, 1984

Digital Repository Service at National Institute of Oceanography (India)

Babu, M.T.; Heblekar, A.K.; Murty, C.S.

Wind distribution observed during southwest monsoon of 1984 has used to derive the mean wind stress for the season at every 1 degree square grid and curl over the Bay of Bengal. Two regions of maximum wind stress are present over the Bay of Bengal...

Identification of three new isolates of Tomato spotted wilt virus from different hosts in China: molecular diversity, phylogenetic and recombination analyses.

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Zhang, Zhenjia; Wang, Deya; Yu, Chengming; Wang, Zenghui; Dong, Jiahong; Shi, Kerong; Yuan, Xuefeng

2016-01-14

Destructive diseases caused by Tomato spotted wilt virus (TSWV) have been reported associated with many important plants worldwide. Recently, TSWV was reported to infect different hosts in China. It is of value to clone TSWV isolates from different hosts and examine diversity and evolution among different TSWV isolates in China as well as worldwide. RT-PCR was used to clone the full-length genome (L, M and S segments) of three new isolates of TSWV that infected different hosts (tobacco, red pepper and green pepper) in China. Identity of nucleotide and amino acid sequences among TSWV isolates were analyzed by DNAMAN. MEGA 5.0 was used to construct phylogenetic trees. RDP4 was used to detect recombination events during evolution of these isolates. Whole-genome sequences of three new TSWV isolates in China were determined. Together with other available isolates, 29 RNA L, 62 RNA M and 66 RNA S of TSWV isolates were analyzed for molecular diversity, phylogenetic and recombination events. This analysis revealed that the entire TSWV genome, especially the M and S RNAs, had major variations in genomic size that mainly involve the A-U rich intergenic region (IGR). Phylogenetic analyses on TSWV isolates worldwide revealed evidence for frequent reassortments in the evolution of tripartite negative-sense RNA genome. Significant numbers of recombination events with apparent 5' regional preference were detected among TSWV isolates worldwide. Moreover, TSWV isolates with similar recombination events usually had closer relationships in phylogenetic trees. All five Chinese TSWV isolates including three TSWV isolates of this study and previously reported two isolates can be divided into two groups with different origins based on molecular diversity and phylogenetic analysis. During their evolution, both reassortment and recombination played roles. These results suggest that recombination could be an important mechanism in the evolution of multipartite RNA viruses, even negative

Sweepoviruses cause disease in sweet potato and related Ipomoea spp.: fulfilling Koch's postulates for a divergent group in the genus begomovirus.

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Trenado, Helena P; Orílio, Anelise F; Márquez-Martín, Belén; Moriones, Enrique; Navas-Castillo, Jesús

2011-01-01

Sweet potato (Ipomoea batatas) and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae), known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV), Sweet potato leaf curl Spain virus (SPLCSV) and Sweet potato leaf curl Canary virus (SPLCCaV). Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06) of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato) and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, 'Beauregard' and 'Promesa', were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus.

Sweepoviruses cause disease in sweet potato and related Ipomoea spp.: fulfilling Koch's postulates for a divergent group in the genus begomovirus.

Directory of Open Access Journals (Sweden)

Helena P Trenado

Full Text Available Sweet potato (Ipomoea batatas and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae, known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV, Sweet potato leaf curl Spain virus (SPLCSV and Sweet potato leaf curl Canary virus (SPLCCaV. Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06 of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, 'Beauregard' and 'Promesa', were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus.

Clinical Presentation and Care of Patients with Ebola Virus Disease in the China Ebola Treatment Unit, Liberia.

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Shao, Xiaoping; Ren, Weizheng; Zhou, Feihu

2017-01-24

In order to evaluate the clinical characteristics of confirmed Ebola Virus Disease (EVD) patients admitted to the China Ebola Treatment Unit (China ETU) between January 2015 and March 2015, we retrospectively analyzed clinical symptoms, treatment, and epidemiologic features of 5 patients with confirmed EVD, and reviewed the relevant medical literature. Of these, 3 patients survived, and 2 died. The time interval from the onset of symptoms to the negative PCR test for Ebola virus in the 3 survivors was 14-18 days. All survivors reported direct contact with confirmed EVD patients up to 21 days prior to admission. All patients developed a fever, fatigue, and anorexia. Fever was generally the first symptom to develop, followed by a gastrointestinal phase characterized by vomiting/nausea (3 cases, 60%), diarrhea (3 cases), and abdominal pain (4 cases, 80%). Three patients (60%) reported joint pain, muscle pain, and conjunctival hemorrhage, respectively, and 2 patients (40%) developed a headache. We concluded that strict isolation and interruption of the route of transmission were required for suspected or confirmed EVD patients. The main treatment strategies were supportive care, maintenance of blood volume and electrolyte balance, and the prevention of complications.

Detection and phylogenetic analyses of spike genes in porcine epidemic diarrhea virus strains circulating in China in 2016-2017.

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Zhang, Qiaoling; Liu, Xinsheng; Fang, Yuzhen; Zhou, Peng; Wang, Yonglu; Zhang, Yongguang

2017-10-10

Large-scale outbreaks of porcine epidemic diarrhea (PED) have re-emerged in China in recent years. However, little is known about the genetic diversity and molecular epidemiology of field strains of PED virus (PEDV) in China in 2016-2017. To address this issue, in this study, 116 diarrhea samples were collected from pig farms in 6 Chinese provinces in 2016-2017 and were detected using PCR for main porcine enteric pathogens, including PEDV, porcine deltacoronavirus (PDCoV), porcine transmissible gastroenteritis virus (TGEV) and porcine kobuvirus (PKV). In addition, the complete S genes from 11 representative PEDV strains were sequenced and analyzed. PCR detection showed that 52.6% (61/116) of these samples were positive for PEDV. Furthermore, sequencing results for the spike (S) genes from 11 of the epidemic PEDV strains showed 93-94% nucleotide identity and 92-93% amino acid identity with the classical CV777 strain. Compared with the CV777 vaccine strain, these strains had an insertion (A 133 ), a deletion (G 155 ), and a continuous 4-amino-acid insertion ( 56 NNTN 59 ) in the S1 region. Phylogenetic analysis based on the S gene indicated that the 11 assessed PEDV strains were genetically diverse and clustered into the G2 group. These results demonstrate that the epidemic strains of PEDV in China in 2016-2017 are mainly virulent strains that belong to the G2 group and genetically differ from the vaccine strain. Importantly, this is the first report that the samples collected in Hainan Province were positive for PEDV (59.2%, 25/42). To our knowledge, this article presents the first report of a virulent PEDV strain isolated from Hainan Island, China. The results of this study will contribute to the understanding of the epidemiology and genetic characteristics of PEDV in China.

Experimental Challenge of a Peridomestic Avian Species, European Starlings ( Sturnus vulgaris ), with Novel Influenza A H7N9 Virus from China.

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Hall, Jeffrey S; Ip, Hon S; TeSlaa, Joshua L; Nashold, Sean W; Dusek, Robert J

2016-07-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings ( Sturnus vulgaris ) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Experimental challenge of a peridomestic avian species, European Starlings (Sturnus vulgaris), with novel Influenza A H7N9 virus from China

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Hall, Jeffrey S.; Ip, Hon S.; Teslaa, Joshua L.; Nashold, Sean W.; Dusek, Robert

2016-01-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings (Sturnus vulgaris) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Avian influenza virus and Newcastle disease virus (NDV) surveillance in commercial breeding farm in China and the characterization of Class I NDV isolates.

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Hu, Beixia; Huang, Yanyan; He, Yefeng; Xu, Chuantian; Lu, Xishan; Zhang, Wei; Meng, Bin; Yan, Shigan; Zhang, Xiumei

2010-07-29

In order to determine the actual prevalence of avian influenza virus (AIV) and Newcastle disease virus (NDV) in ducks in Shandong province of China, extensive surveillance studies were carried out in the breeding ducks of an intensive farm from July 2007 to September 2008. Each month cloacal and tracheal swabs were taken from 30 randomly selected birds that appeared healthy. All of the swabs were negative for influenza A virus recovery, whereas 87.5% of tracheal swabs and 100% cloacal swabs collected in September 2007, were positive for Newcastle disease virus isolation. Several NDV isolates were recovered from tracheal and cloacal swabs of apparently healthy ducks. All of the isolates were apathogenic as determined by the MDT and ICPI. The HN gene and the variable region of F gene (nt 47-420) of four isolates selected at random were sequenced. A 374 bp region of F gene and the full length of HN gene were used for phylogenetic analysis. Four isolates were identified as the same isolate based on nucleotide sequences identities of 99.2-100%, displaying a closer phylogenetic relationship to lentogenic Class I viruses. There were 1.9-9.9% nucleotide differences between the isolates and other Class I virus in the variable region of F gene (nt 47-420), whereas there were 38.5-41.2% nucleotide difference between the isolates and Class II viruses. The amino acid sequences of the F protein cleavage sites in these isolates were 112-ERQERL-117. The full length of HN gene of these isolates was 1851 bp, coding 585 amino acids. The homology analysis of the nucleotide sequence of HN gene indicated that there were 2.0-4.2% nucleotide differences between the isolates and other Class I viruses, whereas there were 29.5-40.9% differences between the isolates and Class II viruses. The results shows that these isolates are not phylogenetically related to the vaccine strain (LaSota). This study adds to the understanding of the ecology of influenza viruses and Newcastle disease viruses in

Phylogenetic analysis of the haemagglutinin gene of canine distemper virus strains detected from giant panda and raccoon dogs in China

Science.gov (United States)

2013-01-01

Background Canine distemper virus (CDV) infects a variety of carnivores, including wild and domestic Canidae. In this study, we sequenced and phylogenetic analyses of the hemagglutinin (H) genes from eight canine distemper virus (CDV) isolates obtained from seven raccoon dogs (Nyctereutes procyonoides) and a giant panda (Ailuropoda melanoleuca) in China. Results Phylogenetic analysis of the partial hemagglutinin gene sequences showed close clustering for geographic lineages, clearly distinct from vaccine strains and other wild-type foreign CDV strains, all the CDV strains were characterized as Asia-1 genotype and were highly similar to each other (91.5-99.8% nt and 94.4-99.8% aa). The giant panda and raccoon dogs all were 549Y on the HA protein in this study, irrespective of the host species. Conclusions These findings enhance our knowledge of the genetic characteristics of Chinese CDV isolates, and may facilitate the development of effective strategies for monitoring and controlling CDV for wild canids and non-cainds in China. PMID:23566727

First report of natural infection of Vigna mungo var. silvestris L. by Groundnut bud necrosis virus, a tospovirus

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Mohammad AKRAM

2010-09-01

Full Text Available In the autumn of 2008, Vigna mungo var. silvestris growing in the experimental field of the Indian Institute of Pulses Research, Kanpur, India, showed chlorosis around some lateral veins and vein branches (mainly near the leaflet margin, downward curling of the leaf margins, necrosis of the stems and petioles, and twisting of the leaflets. Disease incidence was 20%. Symptoms indicated that the cause was Groundnut bud necrosis virus. The virus was identified on the basis of the symptoms on the diagnostic host, and the reverse transcription polymerase chain reaction (RT-PCR using specific primers of the NSm and NP genes. To our knowledge this is the first report of Groundnut bud necrosis virus on V. mungo var. silvestris.

Flat acoustic lens by acoustic grating with curled slits

KAUST Repository

Peng, Pai

2014-10-01

We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

Reassortant H9N2 influenza viruses containing H5N1-like PB1 genes isolated from black-billed magpies in Southern China.

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Guoying Dong

Full Text Available H9N2 influenza A viruses have become endemic in different types of terrestrial poultry and wild birds in Asia, and are occasionally transmitted to humans and pigs. To evaluate the role of black-billed magpies (Pica pica in the evolution of influenza A virus, we conducted two epidemic surveys on avian influenza viruses in wild black-billed magpies in Guangxi, China in 2005 and characterized three isolated black-billed magpie H9N2 viruses (BbM viruses. Phylogenetic analysis indicated that three BbM viruses were almost identical with 99.7 to 100% nucleotide homology in their whole genomes, and were reassortants containing BJ94-like (Ck/BJ/1/94 HA, NA, M, and NS genes, SH/F/98-like (Ck/SH/F/98 PB2, PA, and NP genes, and H5N1-like (Ck/YN/1252/03, clade 1 PB1 genes. Genetic analysis showed that BbM viruses were most likely the result of multiple reassortments between co-circulating H9N2-like and H5N1-like viruses, and were genetically different from other H9N2 viruses because of the existence of H5N1-like PB1 genes. Genotypical analysis revealed that BbM viruses evolved from diverse sources and belonged to a novel genotype (B46 discovered in our recent study. Molecular analysis suggested that BbM viruses were likely low pathogenic reassortants. However, results of our pathogenicity study demonstrated that BbM viruses replicated efficiently in chickens and a mammalian mouse model but were not lethal for infected chickens and mice. Antigenic analysis showed that BbM viruses were antigenic heterologous with the H9N2 vaccine strain. Our study is probably the first report to document and characterize H9N2 influenza viruses isolated from black-billed magpies in southern China. Our results suggest that black-billed magpies were susceptible to H9N2 influenza viruses, which raise concerns over possible transmissions of reassortant H9N2 viruses among poultry and wild birds.

An improved electrochemiluminescence polymerase chain reaction method for highly sensitive detection of plant viruses

International Nuclear Information System (INIS)

Tang Yabing; Xing Da; Zhu Debin; Liu Jinfeng

2007-01-01

Recently, we have reported an electrochemiluminescence polymerase chain reaction (ECL-PCR) method for detection of genetically modified organisms. The ECL-PCR method was further improved in the current study by introducing a multi-purpose nucleic acid sequence that was specific to the tris(bipyridine) ruthenium (TBR) labeled probe, into the 5' terminal of the primers. The method was applied to detect plant viruses. Conserved sequence of the plant viruses was amplified by PCR. The product was hybridized with a biotin labeled probe and a TBR labeled probe. The hybridization product was separated by streptavidin-coated magnetic beads, and detected by measuring the ECL signals of the TBR labeled. Under the optimized conditions, the experiment results show that the detection limit is 50 fmol of PCR products, and the signal-to-noise ratio is in excess of 14.6. The method was used to detect banana streak virus, banana bunchy top virus, and papaya leaf curl virus. The experiment results show that this method could reliably identity viruses infected plant samples. The improved ECL-PCR approach has higher sensitivity and lower cost than previous approach. It can effectively detect the plant viruses with simplicity, stability, and high sensitivity

Molecular characterization and evolutionary analysis of soybean mosaic virus infecting Pinellia ternata in China.

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Sun, Haohua; ShenTu, Susu; Xue, Feng; Duns, Greg; Chen, Jishuang

2008-02-01

Twenty-nine Pinellia ternata specimens were collected from representative areas in China, including the major production provinces of Zhejiang, Henan, Shanxi, Hunan, Shandong and Hubei. Seven isolates related to soybean mosaic virus (SMV), which could be pathogenic on P. ternata and some soybean [Glycine max (L.) Merr.] cultivars, were detected using double antibody sandwich immunosorbent assay (DAS-ELISA) and RT-PCR amplification performed with degenerate primer of potyviruses. It is revealed that the common potyvirus infecting P. ternata is, indeed, only SMVs rather than Dasheen mosaic virus (DsMV) as previously reported. Further molecular phylogenetic analysis of the coat protein (CP) genes of these SMV isolates from P. ternata and G. max, along with some other potyvirus members, such as DsMV and Watermelon mosaic virus (WMV) reconstructed the evolutionary route on both nucleotide and amino acid levels. Similarity and homology of nucleotide sequences for SMV CP genes demonstrated high host correlation and low partial habitat correlation, while those of amino acid sequences also showed that the host correlation was more notable than the habitat correlation. The amino acid sequence of conserved region within CP determines the main function, which shows high homology between species. This study outspreaded from the viruses themselves and their relationship to the infected hosts and revealed the evolutionary strategies, especially the rapid variation or recombination of SMV of P. ternata, in order to adapt itself naturally to the special host.

Characterization of a New World Monopartite Begomovirus Causing Leaf Curl Disease of Tomato in Ecuador and Peru Reveals a New Direction in Geminivirus Evolution

Science.gov (United States)

Melgarejo, Tomas A.; Kon, Tatsuya; Rojas, Maria R.; Paz-Carrasco, Lenin; Zerbini, F. Murilo

2013-01-01

All characterized whitefly-transmitted geminiviruses (begomoviruses) with origins in the New World (NW) have bipartite genomes composed of a DNA-A and DNA-B component. Recently, an NW begomovirus lacking a DNA-B component was associated with tomato leaf curl disease (ToLCD) in Peru, and it was named Tomato leaf deformation virus (ToLDeV). Here, we show that isolates of ToLDeV associated with ToLCD in Ecuador and Peru have a single, genetically diverse genomic DNA that is most closely related to DNA-A components of NW bipartite begomoviruses. Agroinoculation of multimeric clones of the genomic DNA of three ToLDeV genotypes (two variants and a strain) resulted in the development of tomato leaf curl symptoms indistinguishable from those of ToLCD in Ecuador and Peru. Biological properties of these ToLDeV genotypes were similar to those of Old World (OW) monopartite tomato-infecting begomoviruses, including lack of sap transmissibility, phloem limitation, a resistance phenotype in tomato germplasm with the Ty-1 gene, and functional properties of the V1 (capsid protein) and C4 genes. Differences in symptom phenotypes induced by the ToLDeV genotypes in tomato and Nicotiana benthamiana plants were associated with a highly divergent left intergenic region and C4 gene. Together, these results establish that ToLDeV is an emergent NW monopartite begomovirus that is causing ToLCD in Ecuador and Peru. This is the first report of an indigenous NW monopartite begomovirus, and evidence is presented that it emerged from the DNA-A component of a NW bipartite progenitor via convergent evolution and recombination. PMID:23468482

Epidemiology of hepatitis E virus in China: results from the Third National Viral Hepatitis Prevalence Survey, 2005-2006.

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Zhiyuan Jia

Full Text Available In China, hepatitis E virus (HEV is prevalent and causes disease, but its epidemiological profile is not well understood. We used a commercial enzyme-linked immunosorbent assay to detect total antibodies to hepatitis E virus in 15,862 serum samples collected during the Third National Viral Hepatitis Prevalence Survey. The results were analyzed to calculate estimates of HEV seroprevalence and to examine the effects of some putative risk factors. The seroprevalence of HEV in the general Chinese population during the period from 2005 through 2006 was 23.46% (95% confidence interval [CI], 18.41%-28.50%. The farming population, the age group of 15-60 year olds, and those living in the Midwest or Mideast region and in Xinjiang province had the highest seroprevalence estimates. The prevalence of HEV is high in China. The seroprevalence rate of HEV shows an unbalanced distribution among areas with different geographic location and economic development levels. The characteristics of the distribution associated may be due to the route of HEV transmission (via contaminated water or animal reservoirs. Within the same region, the seroprevalence of HEV is generally increased with age.

Laboratory diagnosis of Ebola virus disease and corresponding biosafety considerations in the China Ebola Treatment Center.

Science.gov (United States)

Huang, Qing; Fu, Wei-Ling; You, Jian-Ping; Mao, Qing

2016-10-01

Ebola virus disease (EVD), caused by Ebola virus (EBOV), is a potent acute infectious disease with a high case-fatality rate. Etiological and serological EBOV detection methods, including techniques that involve the detection of the viral genome, virus-specific antigens and anti-virus antibodies, are standard laboratory diagnostic tests that facilitate confirmation or exclusion of EBOV infection. In addition, routine blood tests, liver and kidney function tests, electrolytes and coagulation tests and other diagnostic examinations are important for the clinical diagnosis and treatment of EVD. Because of the viral load in body fluids and secretions from EVD patients, all body fluids are highly contagious. As a result, biosafety control measures during the collection, transport and testing of clinical specimens obtained from individuals scheduled to undergo EBOV infection testing (including suspected, probable and confirmed cases) are crucial. This report has been generated following extensive work experience in the China Ebola Treatment Center (ETC) in Liberia and incorporates important information pertaining to relevant diagnostic standards, clinical significance, operational procedures, safety controls and other issues related to laboratory testing of EVD. Relevant opinions and suggestions are presented in this report to provide contextual awareness associated with the development of standards and/or guidelines related to EVD laboratory testing.

Complete genomic characterization of milk vetch dwarf virus isolates from cowpea and broad bean in Anhui province, China.

Science.gov (United States)

Zhang, Chenhua; Zheng, Hongying; Yan, Dankan; Han, Kelei; Song, Xijiao; Liu, Yong; Zhang, Dongfang; Chen, Jianping; Yan, Fei

2017-08-01

Cowpea and broad bean plants showing severe stunting and leaf rolling symptoms were observed in Hefei city, Anhui province, China, in 2014. Symptomatic plants from both species were shown to be infected with milk vetch dwarf virus (MDV) by PCR. The complete genomes of MDV isolates from cowpea and broad bean were sequenced. Each of them had eight genomic DNAs that differed between the two isolates by 10.7% in their overall nucleotide sequences. In addition, the MDV genomes from cowpea and broad bean were associated with two and three alphasatellite DNAs, respectively. This is the first report of MDV on cowpea in China and the first complete genome sequences of Chinese MDV isolates.

Preliminary Epidemiology of Human Infections with Highly Pathogenic Avian Influenza A(H7N9) Virus, China, 2017.

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Zhou, Lei; Tan, Yi; Kang, Min; Liu, Fuqiang; Ren, Ruiqi; Wang, Yali; Chen, Tao; Yang, Yiping; Li, Chao; Wu, Jie; Zhang, Hengjiao; Li, Dan; Greene, Carolyn M; Zhou, Suizan; Iuliano, A Danielle; Havers, Fiona; Ni, Daxin; Wang, Dayan; Feng, Zijian; Uyeki, Timothy M; Li, Qun

2017-08-01

We compared the characteristics of cases of highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) A(H7N9) virus infections in China. HPAI A(H7N9) case-patients were more likely to have had exposure to sick and dead poultry in rural areas and were hospitalized earlier than were LPAI A(H7N9) case-patients.

Effect of cotton leaf-curl virus on the yield-components and fibre properties of cotton genotypes under varying plant spacing and nitrogen fertilizer

International Nuclear Information System (INIS)

Ahmad, S.; Hayat, K.; Ashraf, F.; Sadiq, M.A.

2008-01-01

Cotton leaf-curl virus (CLCu VB. Wala strain) is one of the major biotic constraints of cotton production in Punjab. Development of resistant cotton genotype is the most feasible, economical and effective method to combat this hazardous problem, but so far no resistant genotype has been reported. Therefore, the objective of this study was to compare yield and yield-components and fiber traits of different genotypes/varieties under different plant spacing and nitrogen fertilizer as a management strategy to cope with this viral disease. Field experiment was conducted during 2006-07 to evaluate the effect of genotype, plant spacing and nitrogen fertilizer on cotton. Five genotypes (MNH-786, MNH-789, MNH- 6070, CIM- 496, and BH-160), three plant-spacings (15, 30 and 45 cm) and three nitrogen fertilizer-levels (6.5, 8.6 and 11 bags Urea / ha) were studied. Results showed that significant differences exist for plant height, no. of bolls/m/sup -2/, seed-cotton yield (kg/ha) due to genotype, interaction of genotype with plant spacing and nitrogen fertilizer level. Whereas boll weight, ginning out-turn, staple length and fiber fineness were not affected significantly by the plant spacing and nitrogen fertilizer, the effect due to genotype was significant for these traits. CLCuV infestation varied significantly with genotypes, while all other factors, i.e., plant spacing and nitrogen fertilizers, have non-significant effect. As the major objective of cotton cultivation is production of lint for the country and seed- cotton yield for the farmers, it is noted that genotypes grown in narrow plant-spacing (15 cm) and higher nitrogen fertilizer level (11.0 bags of urea/ha) produced maximum seed-cotton yield under higher CLCu V infestation in case of CIM-496, MNH-789 and BH-I60, while the new strain MNH-6070 gave maximum yield under 30cm plant-spacing and 8.6 bags of urea/ha has the 2.3% CLCu V infestation was observed in this variety. From the present study, it is concluded that

Effect of Live Poultry Market Closure on Avian Influenza A(H7N9) Virus Activity in Guangzhou, China, 2014

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Yuan, Jun; Lau, Eric H.Y.; Li, Kuibiao; Leung, Y.H. Connie; Yang, Zhicong; Xie, Caojun; Liu, Yufei; Liu, Yanhui; Ma, Xiaowei; Liu, Jianping; Li, Xiaoquan; Chen, Kuncai; Luo, Lei; Di, Biao; Cowling, Benjamin J.; Leung, Gabriel M.; Peiris, Malik

2015-01-01

We assessed the effect of closing live poultry markets in China on influenza A(H7N9) virus detection and viability. Intensive sampling was carried out before, during, and after a 2-week citywide market closure; the markets were cleaned and disinfected at the beginning of the closure period. Swab samples were collected at different sites within the markets and tested for H7N9 by real-time reverse transcription PCR and culture. During the closure, H7N9 viral RNA detection and isolation rates in retail markets decreased by 79% (95% CI 64%–88%) and 92% (95% CI 58%–98%), respectively. However, viable H7N9 virus could be cultured from wastewater samples collected up to 2 days after the market closure began. Our findings indicates that poultry workers and the general population are constantly exposed to H7N9 virus at these markets and that market closure and disinfection rapidly reduces the amount of viable virus. PMID:26402310

Temporal Changes in the Modes of Hepatitis C Virus Transmission in the USA and Northern China.

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Wu, Elizabeth; Yang, Ming; Rao, Huiying; Fu, Sherry; Feng, Bo; Fei, Ran; Lin, Andy; Fontana, Robert J; Wei, Lai; Lok, Anna S

2017-08-01

Predominant modes of hepatitis C virus (HCV) transmission vary between countries and over time. To compare HCV transmission modes in the USA and northern China. We conducted a prospective study enrolling two cohorts of chronic HCV patients in the USA, and in China at Beijing, and at Gu'an and Kuancheng counties in Hebei. Patients self-reported the most likely source and year of infection. A total of 1957 patients were studied (1000 USA; 957 China-428 Beijing, 387 Gu'an, 142 Kuancheng). The predominant infection sources were transfusion (23.0%) and injection drug use (IDU) (32.1%) in the USA and transfusion (64.5%) in northern China. Within China, transfusion was the most common source in Beijing (62.1%) and Gu'an (88.1%), and medical procedures (35.9%) and IDU (12.0%) in Kuancheng. Infection via transfusion decreased significantly in the USA (35.1-4.6%) and Beijing (84.2-14.3%) but remained frequent in Gu'an (90.5-72.5%) over time. Infection via IDU decreased from 32.4% in those ≥61 years to 25.0% in those 41-50 years but increased to 46.5% in those ≤40 years in US patients and decreased over time from 38.7 to 1.9% in Kuancheng. Infection via medical procedures increased over time in Beijing (7.0-33.3%) and remained frequent in Kuancheng (45.2-31.1%). There are major differences in presumed HCV infection source between the USA and northern China. Favorable as well as worrisome changes in the modes of HCV transmission in both countries were observed.

Molecular characterization and phylogenetic analysis of Sugarcane yellow leaf virus isolates from China.

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Gao, San-Ji; Lin, Yi-Hua; Pan, Yong-Bao; Damaj, Mona B; Wang, Qin-Nan; Mirkov, T Erik; Chen, Ru-Kai

2012-10-01

Sugarcane yellow leaf virus (SCYLV) (genus Polerovirus, family Luteoviridae), the causal agent of sugarcane yellow leaf disease (YLD), was first detected in China in 2006. To assess the distribution of SCYLV in the major sugarcane-growing Chinese provinces, leaf samples from 22 sugarcane clones (Saccharum spp. hybrid) showing YLD symptoms were collected and analyzed for infection by the virus using reverse transcription PCR (RT-PCR), quantitative RT-PCR, and immunological assays. A complete genomic sequence (5,879 nt) of the Chinese SCYLV isolate CHN-FJ1 and partial genomic sequences (2,915 nt) of 13 other Chinese SCYLV isolates from this study were amplified, cloned, and sequenced. The genomic sequence of the CHN-FJ1 isolate was found to share a high identity (98.4-99.1 %) with those of the Brazilian (BRA) genotype isolates and a low identity (86.5-86.9 %) with those of the CHN1 and Cuban (CUB) genotype isolates. The genetic diversity of these 14 Chinese SCYLV isolates was assessed along with that of 29 SCYLV isolates of worldwide origin reported in the GenBank database, based on the full or partial genomic sequence. Phylogenetic analysis demonstrated that all the 14 Chinese SCYLV isolates clustered into one large group with the BRA genotype and 12 other reported SCYLV isolates. In addition, five reported Chinese SCYLV isolates were grouped with the Peruvian (PER), CHN1 and CUB genotypes. We therefore speculated that at least four SCYLV genotypes, BRA, PER, CHN1, and CUB, are associated with YLD in China. Interestingly, a 39-nt deletion was detected in the sequence of the CHN-GD3 isolate, in the middle of the ORF1 region adjacent to the overlap between ORF1 and ORF2. This location is known to be one of the recombination breakpoints in the Luteoviridae family.

Human infection with a highly pathogenic avian influenza A (H5N6) virus in Yunnan province, China.

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Xu, Wen; Li, Hong; Jiang, Li

2016-01-01

Highly pathogenic avian influenza A H5N6 virus has caused four human infections in China. This study reports the preliminary findings of the first known human case of H5N6 in Yunnan province. The patient initially developed symptoms of sore throat and coughing on 27 January 2015. The disease rapidly progressed to severe pneumonia, multiple organ dysfunctions and acute respiratory distress syndrome and the patient died on 6 February. Virological analysis determined that the virus belonged to H5 clade 2.3.4.4 and it has obtained partial ability for mammalian adaptation and amantadine resistance. Environmental investigation found H5 in 63% of the samples including poultry faeces, tissues, cage surface swabs and sewage from local live poultry markets by real-time RT-PCR. These findings suggest that the expanding and enhancing of surveillance in both avian and humans are necessary to monitor the evolution of H5 influenza virus and to facilitate early detection of suspected cases.

Genotypic and geographical distribution of porcine reproductive and respiratory syndrome viruses in mainland China in 1996-2016.

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Gao, Jia-Cong; Xiong, Jun-Yao; Ye, Chao; Chang, Xiao-Bo; Guo, Jin-Chao; Jiang, Cheng-Gang; Zhang, Gui-Hong; Tian, Zhi-Jun; Cai, Xue-Hui; Tong, Guang-Zhi; An, Tong-Qing

2017-09-01

Porcine reproductive and respiratory syndrome (PRRS) has caused huge economic losses to Chinese swine industry and remains a major threat since it was first reported in 1996. However, investigations of molecular epidemiological and genetic diversity of PRRS viruses (PRRSVs) in China were limited to a small number of representative strains collected in several areas. Moreover, lineage classifications reported by individual researchers were quite different. In the present study, we sequenced ORF5 sequences of 217 PRRSVs from clinical samples, retrieved all the available ORF5 sequences of PRRSVs isolated in China in 1996-2016 (n=2213) from GenBank, and systematically analyzed corresponding epidemiological data. NA-type PRRSVs in China were classified into five lineages: lineage 1, lineage 3, lineage 5, lineage 8, and lineage 9. Most strains in China belonged to lineage 8 (85.6%), with dominant strains being classified as sublineage 8.3 (78.3%). Importantly, the emerging lineage 1 and lineage 3 strains spread rapidly, and their proportions among circulating PRRSVs have significantly increased in recent years. The geographical distribution of different PRRSV lineages in each province was analyzed and possible inter-province transmission routes were outlined for main lineages and sublineages. To our knowledge, this study is the most comprehensive and extensive phylogeographical analysis of PRRSVs in China since PRRS outbreak in 1996. Our dataset can serve as a canonical standard for PRRSV classification and will help to study genetic evolution of PRRSV. The results of the present study may also improve prevention of PRRS in China. Copyright © 2017 Elsevier B.V. All rights reserved.

Genotype Distribution and Molecular Epidemiology of Hepatitis C Virus in Hubei, Central China.

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Jing Peng

Full Text Available Little is known about the molecular epidemiology of hepatitis C virus (HCV infection in Central China.A total of 570 patients from Hubei Province in central China were enrolled. These patients were tested positive for HCV antibody prior to blood transfusion. Among them, 177 were characterized by partial NS5B and/or Core-E1 sequences and classified into five subtypes: 1b, 83.0% (147/177; 2a, 13.0% (23/177; 3b, 2.3% (4/177; 6a, 1.1% (2/177; 3a, 0.6% (1/177. Analysis of genotype-associated risk factors revealed that paid blood donation and transfusion before 1997 were strongly associated with subtypes 1b and 2a, while some subtype 2a cases were also found in individuals with high risk sexual behaviors; subtypes 3b, 6a, and 3a were detected only in intravenous drug users. Phylogeographic analyses based on the coalescent datasets demonstrated that 1b, 2a, 3b, and 6a were locally epidemic in Hubei Province. Among them, subtype 1b Hubei strains may have served as the origins of this subtype in China, and 2a and 3b Hubei strains may have descended from the northwest and southwest of China, respectively, while 6a Hubei strains may have been imported from the central south and southwest.The results suggest that the migration patterns of HCV in Hubei are complex and variable among different subtypes. Implementation of mandatory HCV screening before donation has significantly decreased the incidence of transfusion-associated HCV infection since 1997. More attention should be paid to intravenous drug use and unsafe sexual contact, which may have become new risk factors for HCV infection in Hubei Province.

Detection and transmission of Carrot torrado virus, a novel putative member of the Torradovirus genus.

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Rozado-Aguirre, Zuriñe; Adams, Ian; Collins, Larissa; Fox, Adrian; Dickinson, Matthew; Boonham, Neil

2016-09-01

A new Torradovirus tentatively named Carrot torrado virus (CaTV) was an incidental finding following a next generation sequencing study investigating internal vascular necrosis in carrot. The closest related viruses are Lettuce necrotic leaf curl virus (LNLCV) found in the Netherlands in 2011 and Motherwort yellow mottle virus (MYMoV) found in Korea in 2014. Primers for reverse transcriptase-PCR (RT-PCR) and RT-qPCR were designed with the aim of testing for the presence of virus in plant samples collected from the field. Both methods successfully amplified the target from infected samples but not from healthy control samples. The specificity of the CaTV assay was also checked against other known carrot viruses and no cross-reaction was seen. A comparative study between methods showed RT-qPCR was the most reliable method, giving positive results in samples where RT-PCR fails. Evaluation of the Ct values following RT-qPCR and a direct comparison demonstrated this was due to improved sensitivity. The previous published Torradovirus genus specific RT-PCR primers were tested and shown to detect CaTV. Also, virus transmission experiments carried out suggest that unlike other species of the same genus, Carrot torrado virus could be aphid-transmitted. Copyright © 2016 Elsevier B.V. All rights reserved.

Avian Influenza A (H7N9) Virus

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... August 7, 2017 Increase in Human Infections with Avian Influenza A(H7N9) Virus During the Fifth Epidemic — China, October 2016–February 2017 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for ...

Pathogenesis and phylogenetic analyses of canine distemper virus strain ZJ7 isolate from domestic dogs in China

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Tan Bin

2011-11-01

Full Text Available Abstract A new isolate of canine distemper virus (CDV, named ZJ7, was isolated from lung tissues of a dog suspected with CDV infection using MDCK cells. The ZJ7 isolate induced cytopathogenic effects of syncytia in MDCK cell after six passages. In order to evaluate pathogenesis of ZJ7 strain, three CDV sero-negative dogs were intranasally inoculated with its virus suspension. All infected dogs developed clinical signs of severe bloody diarrhea, conjunctivitis, ocular discharge, nasal discharge and coughing, fever and weight loss at 21 dpi, whereas the mock group infected with DMEM were normal. The results demonstrated that CDV-ZJ7 strain isolated by MDCK cell was virulent, and the nucleotide and amino acid sequences of strain ZJ7 had no change after isolation by MDCK cell when compared with the original virus from the fresh tissues. Molecular and phylogenetic analyses for the nucleocapsid (N, phosphoprotein (P and receptor binding haemagglutinin (H gene of the ZJ7 isolate clearly showed it is joins to the Asia 1 group cluster of CDV strains, the predominant genotype in China.

Pathogenesis and phylogenetic analyses of canine distemper virus strain ZJ7 isolate from domestic dogs in China.

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Tan, Bin; Wen, Yong-Jun; Wang, Feng-Xue; Zhang, Shu-Qin; Wang, Xiu-Dong; Hu, Jia-Xin; Shi, Xin-Chuan; Yang, Bo-Chao; Chen, Li-Zhi; Cheng, Shi-Peng; Wu, Hua

2011-11-16

A new isolate of canine distemper virus (CDV), named ZJ7, was isolated from lung tissues of a dog suspected with CDV infection using MDCK cells. The ZJ7 isolate induced cytopathogenic effects of syncytia in MDCK cell after six passages. In order to evaluate pathogenesis of ZJ7 strain, three CDV sero-negative dogs were intranasally inoculated with its virus suspension. All infected dogs developed clinical signs of severe bloody diarrhea, conjunctivitis, ocular discharge, nasal discharge and coughing, fever and weight loss at 21 dpi, whereas the mock group infected with DMEM were normal. The results demonstrated that CDV-ZJ7 strain isolated by MDCK cell was virulent, and the nucleotide and amino acid sequences of strain ZJ7 had no change after isolation by MDCK cell when compared with the original virus from the fresh tissues. Molecular and phylogenetic analyses for the nucleocapsid (N), phosphoprotein (P) and receptor binding haemagglutinin (H) gene of the ZJ7 isolate clearly showed it is joins to the Asia 1 group cluster of CDV strains, the predominant genotype in China.

Chino del tomate virus:Relationships to Other Begomoviruses and Identification of A-Component Variants that Affect Symptom Expression.

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Brown, J K; Ostrow, K M; Idris, A M; Stenger, D C

2000-05-01

Phylogenetic and distance analyses place Chino del tomate virus (CdTV) in the New World clade of begomoviruses and indicate that CdTV and Tomato leaf crumple virus (TLCrV) are closely related strains of the same virus. One cloned CdTV A component (pCdTV-H6), when inoculated to tomato with the B component (pCdTV-B52), produced mild symptoms and low DNA titers. Another cloned CdTV A component (pCdTV-H8), when coinoculated to tomato with the B component, produced moderate leaf curling and veinal chlorosis similar to that of TLCrV. Coinoculation of both CdTV A components and the B component to tomato produced wild-type chino del tomate (CdT) disease symptoms consisting of severe leaf curling, veinal and interveinal chlorosis, and stunting. The two CdTV A components were nearly identical, except at nucleotide positions 1,722 and 2,324. The polymorphism at nucleotide 1,722 resulted in a change at Rep amino acid 261. The second polymorphism at nucleotide 2,324 resulted in changes at Rep amino acid 60 and AC4 amino acid 10. Two chimeric A components constructed by reciprocal exchange of a fragment bearing the polymorphic site at nucleotide 1,722 were evaluated for symptom phenotype. One chimeric A component (pCdTV-H86) produced wild-type CdT symptoms when coinoculated to tomato with the B component. The reciprocal chimeric A component (pCdTV-H68), when coin-oculated to tomato with the B component, also produced severe leaf curling, veinal chlorosis, and stunting. However, pCdTV-H68 induced less obvious interveinal chlorosis than wild-type or pCdTV-H86. Examination of A component genotypes recovered from tomato coinoculated with pCdTV-H6 and pCdTV-H8 indicated that recombination occurred to produce a genotype identical to pCdTV-H86. These results indicate that subtle genotypic variation has significant effects on symptom expression and may explain phenotypic differences observed among isolates and cloned DNAs of CdTV and TLCrV.

Virus Incidence of Sweet Potato in Korea from 2011 to 2014.

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Kim, Jaedeok; Yang, Jung Wook; Kwak, Hae-Ryun; Kim, Mi-Kyeong; Seo, Jang-Kyun; Chung, Mi-Nam; Lee, Hyeong-Un; Lee, Kyeong-Bo; Nam, Sang Sik; Kim, Chang-Seok; Lee, Gwan-Seok; Kim, Jeong-Soo; Lee, Sukchan; Choi, Hong-Soo

2017-10-01

A nationwide survey was performed to investigate the current incidence of viral diseases in Korean sweet potatoes for germplasm and growing fields from 2011 to 2014. A total of 83.8% of the germplasm in Korea was infected with viruses in 2011. Commercial cultivars that were used to supply growing fields were infected at a rate of 62.1% in 2012. Among surveyed viruses, the incidence of five Potyvirus species that infect sweet potato decreased between 2012 and 2013, and then increased again in 2014. Representatively, the incidence of Sweet potato feathery mottle virus (SPFMV) was 87.0% in 2012, 20.7% in 2013 and then increased to 35.3% in 2014. Unlike RNA viruses, DNA viruses were shown to decrease continuously. The incidence of Sweet potato leaf curl virus (SPLCV) was 5.5% in 2003, 59.5% in 2011, and 47.4% in 2012. It then decreased continuously year by year to 33.2% in 2013, and then 25.6% in 2014. While the infection rate of each virus species showed a tendency to decline, the virus infection status was more variable in 2013 and 2014. Nevertheless, the high rate of single infections and mixed infection combinations were more variable than the survey results from 2012. As shown in the results from 2013, the most prevalent virus infection was a single infection at 27.6%, with the highest rate of infection belonging to sweet potato symptomless virus-1 (SPSMV-1) (12.9%). Compared to 2013, infection combinations were more varied in 2014, with a total of 122 kinds of mixed infection.

Engineering resistance against Tomato yellow leaf curl virus via the CRISPR/Cas9 system in tomato

KAUST Repository

Mahfouz, Magdy M.; Tashkandi, Manal; Ali, Zahir; Aljedaani, Fatimah R.; Shami, Ashwag

2017-01-01

CRISPR/Cas systems confer molecular immunity against phages and conjugative plasmids in prokaryotes. Recently, CRISPR/Cas9 systems have been used to confer interference against eukaryotic viruses. Here, we engineered Nicotiana benthamiana and tomato

Complete Genome Sequences of Porcine Epidemic Diarrhea Virus Strains JSLS-1/2015 and JS-2/2015 Isolated from China.

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Tao, Jie; Li, Benqiang; Zhang, Chunling; Liu, Huili

2016-11-10

Two porcine epidemic diarrhea virus (PEDV) strains, JSLS-1/2015 and JS-2/2015, were isolated from piglets with watery diarrhea in South China. Two genomic sequences were highly homologous to the attenuated DR13 strain. Furthermore, JSLS-1/2015 contains a 24-amino-acid deletion in open reading frame 1b, which was first reported in PEDV isolates. Copyright © 2016 Tao et al.

An unusual alphasatellite associated with monopartite begomoviruses attenuates symptoms and reduces betasatellite accumulation

KAUST Repository

Idris, Ali

2010-11-17

The Oman strain of Tomato yellow leaf curl virus (TYLCV-OM) and its associated betasatellite, an isolate of Tomato leaf curl betasatellite (ToLCB), were previously reported from Oman. Here we report the isolation of a second, previously undescribed, begomovirus [Tomato leaf curl Oman virus (ToLCOMV)] and an alphasatellite from that same plant sample. This alphasatellite is closely related (90% shared nucleotide identity) to an unusual DNA-2-type Ageratum yellow vein Singapore alphasatellite (AYVSGA), thus far identified only in Singapore. ToLCOMV was found to have a recombinant genome comprising sequences derived from two extant parents, TYLCV-OM, which is indigenous to Oman, and Papaya leaf curl virus from the Indian subcontinent. All possible combinations of ToLCOMV, TYLCV-OM, ToLCB and AYVSGA were used to agro-inoculate tomato and Nicotiana benthamiana. Infection with ToLCOMV yielded mild leaf-curl symptoms in both hosts; however, plants inoculated with TYLCV-OM developed more severe symptoms. Plants infected with ToLCB in the presence of either helper begomovirus resulted in more severe symptoms. Surprisingly, symptoms in N. benthamiana infected with the alphasatellite together with either of the helper viruses and the betasatellite were attenuated and betasatellite DNA accumulation was substantially reduced. However, in the latter plants no concomitant reduction in the accumulation of helper virus DNA was observed. This is the first example of an attenuation of begomovirus-betasatellite symptoms by this unusual class of alphasatellites. This observation suggests that some DNA-2 alphasatellites encode a pathogenicity determinant that may modulate begomovirus-betasatellite infection by reducing betasatellite DNA accumulation. © 2011 SGM.

An unusual alphasatellite associated with monopartite begomoviruses attenuates symptoms and reduces betasatellite accumulation

KAUST Repository

Idris, Ali; Shahid, Muhammad Shafiq; Briddon, Rob William; Khan, Akhtarjamal; Zhu, Jian-Kang; Brown, Judith K.

2010-01-01

The Oman strain of Tomato yellow leaf curl virus (TYLCV-OM) and its associated betasatellite, an isolate of Tomato leaf curl betasatellite (ToLCB), were previously reported from Oman. Here we report the isolation of a second, previously undescribed, begomovirus [Tomato leaf curl Oman virus (ToLCOMV)] and an alphasatellite from that same plant sample. This alphasatellite is closely related (90% shared nucleotide identity) to an unusual DNA-2-type Ageratum yellow vein Singapore alphasatellite (AYVSGA), thus far identified only in Singapore. ToLCOMV was found to have a recombinant genome comprising sequences derived from two extant parents, TYLCV-OM, which is indigenous to Oman, and Papaya leaf curl virus from the Indian subcontinent. All possible combinations of ToLCOMV, TYLCV-OM, ToLCB and AYVSGA were used to agro-inoculate tomato and Nicotiana benthamiana. Infection with ToLCOMV yielded mild leaf-curl symptoms in both hosts; however, plants inoculated with TYLCV-OM developed more severe symptoms. Plants infected with ToLCB in the presence of either helper begomovirus resulted in more severe symptoms. Surprisingly, symptoms in N. benthamiana infected with the alphasatellite together with either of the helper viruses and the betasatellite were attenuated and betasatellite DNA accumulation was substantially reduced. However, in the latter plants no concomitant reduction in the accumulation of helper virus DNA was observed. This is the first example of an attenuation of begomovirus-betasatellite symptoms by this unusual class of alphasatellites. This observation suggests that some DNA-2 alphasatellites encode a pathogenicity determinant that may modulate begomovirus-betasatellite infection by reducing betasatellite DNA accumulation. © 2011 SGM.

Identification of a Novel Recombinant Type 2 Porcine Reproductive and Respiratory Syndrome Virus in China

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Long Zhou

2018-03-01

Full Text Available Since the emergence of NADC30-like porcine reproductive and respiratory syndrome virus (PRRSV in China in 2013, PRRSVs have undergone rapid evolution. In this study, a novel variant of PRRSV strain (designated SCcd17 was successfully isolated from piglets with clinical signs in Sichuan Province in China in 2017, and the complete genomic sequence was determined. The genome of this new isolate was 15,015 nucleotides (nt long, and comparative analysis revealed that SCcd17 exhibited 90.2%, 85.2%, 84.9%, and 84.0% nucleotide similarity to PRRSVs NADC30, JXA1, CH-1a, and VR-2332, respectively. Phylogenetic analysis indicated that the SCcd17 strain was classified into the NADC30-like sub-genotype, in which all the strains contained the unique discontinuous 131-amino acid deletion in nonstructural protein 2 (nsp2 when compared to VR-2332-like viruses. Notably, extensive amino acid substitutions were observed in nsp2 and a unique single amino acid deletion at position 33 of the GP5 is being described for the first time. Strikingly, recombination analysis revealed that SCcd17 was the result of recombination between the NADC30-like, JXA1-like, and VR-2332-like strains at five recombination breakpoints: nsp1α (nt 641, nsp3 (nt 5141, nsp10 (nt 9521, open reading frame 3 (ORF3 (nt 12,581, and ORF4 (nt 13,021. The genomic data of SCcd17 will be helpful for understanding the role of genomic recombination in the evolution of PRRSV.

Isolation and identification of a bovine viral diarrhea virus from sika deer in china.

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Gao, Yugang; Wang, Shijie; Du, Rui; Wang, Quankai; Sun, Changjiang; Wang, Nan; Zhang, Pengju; Zhang, Lianxue

2011-02-25

Bovine viral diarrhea virus (BVDV) infections continue to cause significantly losses in the deer population. Better isolation and identification of BVDV from sika deer may contribute significantly to the development of prophylactic therapeutic, and diagnostic reagents as well as help in prevention and control of BVDV. However, isolation and identification of BVDV from sika deer is seldom reported in literature. In this study, we collected some samples according to clinical sign of BVDV to isolation and identification of BVDV from sika deer. we isolated a suspected BVDV strain from livers of an aborted fetus from sika deer in Changchun (China) using MDBK cell lines, named as CCSYD strain, and identified it by cytopathic effect (CPE), indirect immunoperoxidase test (IPX) and electron microscopy(EM). The results indicated that this virus was BVDV by a series of identification. The structural proteins E0 gene was cloned and sequenced. The obtained E0 gene sequence has been submitted to GenBank with the accession number: FJ555203. Alignment with other 9 strains of BVDV, 7 strains of classical swine fever virus (CSFV) and 3 strains of border disease virus(BDV) in the world, showed that the homology were 98.6%-84.8%, 76.0%-74.7%, 76.6%-77.0% for nucleotide sequence, respectively. The phylogenetic analysis indicated that new isolation and identification CCSYD strain belonged to BVDV1b. To the best of our knowledge, this is the first report that BVDV was isolated and identified in sika deer. This current research contributes development new BVDV vaccine to prevent and control of BVD in sika deer.

Isolation and identification of a bovine viral diarrhea virus from sika deer in china

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Wang Nan

2011-02-01

Full Text Available Abstract Background Bovine viral diarrhea virus (BVDV infections continue to cause significantly losses in the deer population. Better isolation and identification of BVDV from sika deer may contribute significantly to the development of prophylactic therapeutic, and diagnostic reagents as well as help in prevention and control of BVDV. However, isolation and identification of BVDV from sika deer is seldom reported in literature. In this study, we collected some samples according to clinical sign of BVDV to isolation and identification of BVDV from sika deer. Results we isolated a suspected BVDV strain from livers of an aborted fetus from sika deer in Changchun (China using MDBK cell lines, named as CCSYD strain, and identified it by cytopathic effect (CPE, indirect immunoperoxidase test (IPX and electron microscopy(EM. The results indicated that this virus was BVDV by a series of identification. The structural proteins E0 gene was cloned and sequenced. The obtained E0 gene sequence has been submitted to GenBank with the accession number: FJ555203. Alignment with other 9 strains of BVDV, 7 strains of classical swine fever virus (CSFV and 3 strains of border disease virus(BDV in the world, showed that the homology were 98.6%-84.8%, 76.0%-74.7%, 76.6%-77.0% for nucleotide sequence, respectively. The phylogenetic analysis indicated that new isolation and identification CCSYD strain belonged to BVDV1b. Conclusion To the best of our knowledge, this is the first report that BVDV was isolated and identified in sika deer. This current research contributes development new BVDV vaccine to prevent and control of BVD in sika deer.

Trends in Hepatitis B Virus Resistance to Nucleoside/Nucleotide Analogs in North China from 2009 to 2016: A Retrospective Study.

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Guo, Xianghua; Wu, Jushan; Wei, Feili; Ouyang, Yabo; Li, Qing; Liu, Kai; Wang, Yanjun; Zhang, Yulin; Chen, Dexi

2018-04-11

Nucleos(t)ide analogs (NAs) are widely used in anti-hepatitis B virus (HBV) therapy for effective inhibition of HBV replication. However, HBV resistance to NAs has emerged, resulting in virus reactivation and disease recurrence. Big data on the current dynamic of HBV resistance profiles are still rare in China. Herein, we analyzed 4,491 plasma samples with HBV primary genotypic resistance mutations representative of the general HBV resistance situation in northern China from 2009 to 2016. We found that entecavir (ETV), representing 52.8% of 12,713 NAs users in the North of China in 2016, has become the major NA for treating Chinese patients infected with HBV. Despite more than 50% of M204I/V±L180M among all HBV resistance cases annually and extensive exposure of the patients to lamivudine (LAM), telbivudine (LdT), and adefovir dipivoxil (ADV), ETV resistance also showed dramatically increased incidence, which climbed to 17.1% in 2016. Moreover, A181T/V, ETV-resistant mutations, and multidrug-resistant mutations were found more frequently in HBV genotype C than in HBV genotype B, 21.2% vs. 8.5%, 12.5% vs. 7.9%, and 5.9% vs. 3%, respectively, whereas M204I and N236T were more predominant in genotype B than in genotype C, 40.3% vs. 20.8%, and 11.3% vs. 1.8%, respectively. In conclusion, we have reported dynamic changes of HBV NA-resistance mutation patterns and the current NA usage profile for anti-HBV treatment in North China in the past 8 years. Our data provides valuable information on HBV NA resistance that is an important reference for clinics to devise more effective treatment regimens for individual patients. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Analysis of the complete genome of the first Irkut virus isolate from China: comparison across the Lyssavirus genus.

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Liu, Ye; Li, Nan; Zhang, Shoufeng; Zhang, Fei; Lian, Hai; Wang, Ying; Zhang, Jinxia; Hu, Rongliang

2013-12-01

The genome of Irkut virus, isolate IRKV-THChina12, the first non-rabies lyssavirus from China (of bat origin), has been completely sequenced. In general, coding and non-coding regions of this viral genome are similar to those of other lyssaviruses. However, alignment of the deduced amino acid sequences of the structural proteins of IRKV-THChina12 with those of other lyssavirus representatives revealed significant variability between viral species. The nucleoprotein and matrix protein were found to be the most conserved, followed by the large protein, glycoprotein and phosphoprotein. Differences in the antigenic sites in glycoprotein may result in only partial protection of the available rabies biologics against Irkut virus, which is of particular concern for pre- and post-exposure rabies prophylaxis. Copyright © 2013 Elsevier Inc. All rights reserved.

The single-leg Roman chair hold is more effective than the Nordic hamstring curl in improving hamstring strength-endurance in Gaelic footballers with previous hamstring injury.

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Macdonald, Ben; O'Neill, John; Pollock, Noel; Van Hooren, Bas

2018-03-06

Poor hamstring strength-endurance is a risk factor for hamstring injuries. This study investigated the effectiveness of the single-leg Roman hold and Nordic hamstring curl in improving hamstring strength-endurance. Twelve Gaelic footballers (mean ± standard deviation age, height and mass were 25.17 ± 3.46 years, 179.25 ± 5.88 cm, 85.75 ± 4.75 kilo) with a history of hamstring injury were randomized into 2 groups that performed 6 weeks of either Nordic hamstring curl, or single-leg Roman chair hold training. The single-leg hamstring bridge (SLHB) was measured pre- and post- intervention. The Roman chair group showed a very likely moderate magnitude improvement on SLHB performance for both legs (23.7% for the previously injured leg [90% confidence interval 9.6% to 39.6%] and 16.9% for the non-injured leg [6.2% to 28.8%]). The Nordic curl group showed a likely trivial change in SLHB performance for the non-injured leg (-2.1% [-6.7% to 2.6%]) and an unclear, but possibly trivial change for the previously injured leg (0.3% [-5.6% to 6.6%]). The Roman chair group improved very likely more with a moderate magnitude in both the non-injured (19.5% [8.0% to 32.2%]) and the previously injured leg (23.3% [8.5% to 40.0%]) compared to the Nordic curl group. This study demonstrated that 6-weeks single-leg Roman chair training substantially improved SLHB performance, suggesting that it may be an efficacious strategy to mitigate hamstring (re-) injury risk. Conversely, 6-weeks Nordic curl training did not substantially improve SLHB performance, suggesting this may not be the intervention of choice for modifying this risk factor.

Genome characterization of sugarcane yellow leaf virus from China reveals a novel recombinant genotype.

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Lin, Yi-Hua; Gao, San-Ji; Damaj, Mona B; Fu, Hua-Ying; Chen, Ru-Kai; Mirkov, T Erik

2014-06-01

Sugarcane yellow leaf virus (SCYLV; genus Polerovirus, family Luteoviridae) is a recombinant virus associated with yellow leaf disease, a serious threat to sugarcane in China and worldwide. Among the nine known SCYLV genotypes existing worldwide, COL, HAW, REU, IND, CHN1, CHN2, BRA, CUB and PER, the last five have been reported in China. In this study, the complete genome sequences (5,880 nt) of GZ-GZ18 and HN-CP502 isolates from the Chinese provinces of Guizhou and Hainan, respectively, were cloned, sequenced and characterized. Phylogenetic analysis showed that, among 29 SCYLV isolates described worldwide, the two Chinese isolates clustered together into an independent clade based on the near-complete genome nucleotide (ORF0-ORF5) or amino acid sequences of individual genes, except for the MP protein (ORF4). We propose that the two isolates represent a novel genotype, CHN3, diverging from other genotypes by 1.7-13.6 % nucleotide differences in ORF0-ORF5, and 2.7-28.1 %, 1.8-20.4 %, 0.5-5.1 % and 2.7-15.9 % amino acid differences in P0 (ORF0), RdRp (RNA-dependent RNA polymerase) (ORF1+2), CP (coat protein) (ORF3) and RT (readthrough protein) (ORF3+5), respectively. CHN3 was closely related to the BRA, HAW and PER genotypes, differing by 1.7-3.8 % in the near-complete genome nucleotide sequence. Recombination analysis further identified CHN3 as a new recombinant strain, arising from the major parent CHN-HN1 and the minor parent CHN-GD-WY19. Recombination breakpoints were distributed mostly within the RdRp region in CHN3 and the four significant recombinant genotypes, IND, REU, CUB and BRA. Recombination is considered to contribute significantly to the evolution and emergence of such new SCYLV variants.

Geometric classification of scalp hair for valid drug testing, 6 more reliable than 8 hair curl groups.

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K Mkentane

Full Text Available Curly hair is reported to contain higher lipid content than straight hair, which may influence incorporation of lipid soluble drugs. The use of race to describe hair curl variation (Asian, Caucasian and African is unscientific yet common in medical literature (including reports of drug levels in hair. This study investigated the reliability of a geometric classification of hair (based on 3 measurements: the curve diameter, curl index and number of waves.After ethical approval and informed consent, proximal virgin (6cm hair sampled from the vertex of scalp in 48 healthy volunteers were evaluated. Three raters each scored hairs from 48 volunteers at two occasions each for the 8 and 6-group classifications. One rater applied the 6-group classification to 80 additional volunteers in order to further confirm the reliability of this system. The Kappa statistic was used to assess intra and inter rater agreement.Each rater classified 480 hairs on each occasion. No rater classified any volunteer's 10 hairs into the same group; the most frequently occurring group was used for analysis. The inter-rater agreement was poor for the 8-groups (k = 0.418 but improved for the 6-groups (k = 0.671. The intra-rater agreement also improved (k = 0.444 to 0.648 versus 0.599 to 0.836 for 6-groups; that for the one evaluator for all volunteers was good (k = 0.754.Although small, this is the first study to test the reliability of a geometric classification. The 6-group method is more reliable. However, a digital classification system is likely to reduce operator error. A reliable objective classification of human hair curl is long overdue, particularly with the increasing use of hair as a testing substrate for treatment compliance in Medicine.

Genetic diversity/impurity estimation in sources of natural resistance against cotton leaf curl disease in pakistan

International Nuclear Information System (INIS)

Sarwar, G.

2007-01-01

Cotton accounts for more than 60% of Pakistan's export earnings through the export of both raw cotton and cotton products. An epidemic of cotton leaf curl disease (CLCuD) in Pakistan during the 1990s led to the withdrawal of high yielding cotton cultivars. Due of their susceptibility to the disease. The identification of natural resistance in some genotypes provided a means to manage reduce losses due to the disease. But it has been an adversity that almost all these resistant varieties have ultimately 'lost' their resistance. There are also reports that the original sources of resistance, as well as the varieties developed from them, are now susceptible to the disease when grafted with infected scion. For the present studies. Seed of two resistant varieties (LRA-5166 and (CP-152) was obtained from six different research organizations. Plants raised from these seed were grafted with symptomatic scion and used for morphological comparisons. Our results indicated that the genetic pool of these cultivars is not well maintained and that an unacceptable diversity impurity is present within and among the genetic stock of both these lines. There is thus a requirement for screening of these elite lines at the molecular level to ensure the purity of these varieties for future development. The virus causing CLCuD showed change by recombination making the search for new sources of resistance, as well as the maintenance of established sources, indispensable for the sustainable cotton production in Pakistan. (author)

Hepatitis E virus infection in central China reveals no evidence of cross-species transmission between human and swine in this area.

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Wen Zhang

Full Text Available Hepatitis E virus (HEV is a zoonotic pathogen of which several species of animal were reported as reservoirs. Swine stands out as the major reservoir for HEV infection in humans, as suggested by the close genetic relationship of swine and human virus. Since 2000, Genotype 4 HEV has become the dominant cause of hepatitis E disease in China. Recent reports showed that genotype 4 HEV is freely transmitted between humans and swine in eastern and southern China. However, the infection status of HEV in human and swine populations in central China is still unclear. This study was conducted in a rural area of central China, where there are many commercial swine farms. A total of 1476 serum and 554 fecal specimens were collected from the general human and swine populations in this area, respectively. The seroepidemiological study was conducted by enzyme-linked immunosorbent assay. Conserved genomic sequences of open reading frame 2 were detected using reverse transcription-PCR. The results indicated that the overall viral burden of the general human subjects was 0.95% (14/1476, while 7.0% (39/554 of the swine excreted HEV in stool. The positive rate of anti-HEV IgG and IgM in the serum samples was 7.9% (117/1476 and 1.6% (24/1476, respectively. Phylogenetic analysis based on the 150 nt partial sequence of the capsid protein gene showed that the 53 swine and human HEV isolates in the current study all belonged to genotype 4, clustering into three major groups. However, the HEV isolates prevalent in the human and swine populations were classified into known distinct subgenotypes, which suggested that no cross-species transmission between swine and humans had taken place in this area. This result was confirmed by cloning and phylogenetic analysis of the complete capsid protein gene sequence of three representative HEV strains in the three major groups. The cross reactivity between anti-HEV IgG from human sera and the two representative strains from swine in

Incidence, Distribution and Characteristics of Major Tomato Leaf Curl and Mosaic Virus Diseases in Uganda

OpenAIRE

Ssekyewa, C

2006-01-01

In Uganda, about 3 million households consume tomato. However, tomato yields (10 ton/ ha) are low due to poor agronomic practices, lack of high yielding and disease resistant varieties, and pests (Varela, 1995; Hansen, 1990; Defrancq, 1989). Viral diseases are the third major cause of low tomato productivity in Uganda. Therefore, a survey was conducted; symptoms observed on tomato were categorized, and screened for both ribonucleic and deoxyribonucleic acid tomato viruses. Genetic identity fo...

Evidence for Cross-species Influenza A Virus Transmission Within Swine Farms, China: A One Health, Prospective Cohort Study.

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Ma, Mai-Juan; Wang, Guo-Lin; Anderson, Benjamin D; Bi, Zhen-Qiang; Lu, Bing; Wang, Xian-Jun; Wang, Chuang-Xin; Chen, Shan-Hui; Qian, Yan-Hua; Song, Shao-Xia; Li, Min; Lednicky, John A; Zhao, Teng; Wu, Meng-Na; Cao, Wu-Chun; Gray, Gregory C

2018-02-01

Our understanding of influenza A virus transmission between humans and pigs is limited. Beginning in 2015, we used a One Health approach and serial sampling to prospectively study 299 swine workers and 100 controls, their 9000 pigs, and 6 pig farm environments in China for influenza A viruses (IAVs) using molecular, culture, and immunological techniques. Study participants were closely monitored for influenza-like illness (ILI) events. Upon enrollment, swine workers had higher serum neutralizing antibody titers against swine H1N1 and higher nasal wash total immunoglobulin A (IgA) and specific IgA titers against swine H1N1 and H3N2 viruses. Over a period of 12 months, IAVs were detected by quantitative reverse-transcription polymerase chain reaction in 46 of 396 (11.6%) environmental swabs, 235 of 3300 (7.1%) pig oral secretion, 23 of 396 (5.8%) water, 20 of 396 (5.1%) aerosol, and 19 of 396 (4.8%) fecal-slurry specimens. Five of 32 (15.6%) participants with ILI events had nasopharyngeal swab specimens that were positive for IAV, and 17 (53.1%) demonstrated 4-fold rises in neutralization titers against a swine virus. Reassorted Eurasian avian-lineage H1N1, A(H1N1)pdm09-like, and swine-lineage H3N2 viruses were identified in pig farms. The A(H1N1)pdm09-like H1N1 viruses identified in swine were nearly genetically identical to the human H1N1 viruses isolated from the participants with ILI. There was considerable evidence of A(H1N1)pdm09-like, swine-lineage H1N1, and swine-lineage H3N2 viruses circulating, likely reassorting, and likely crossing species within the pig farms. These data suggest that stronger surveillance for novel influenza virus emergence within swine farms is imperative. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

New frontiers in oncolytic viruses: optimizing and selecting for virus strains with improved efficacy

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Lundstrom K

2018-02-01

Full Text Available Kenneth Lundstrom PanTherapeutics, Lutry, Switzerland Abstract: Oncolytic viruses have demonstrated selective replication and killing of tumor cells. Different types of oncolytic viruses – adenoviruses, alphaviruses, herpes simplex viruses, Newcastle disease viruses, rhabdoviruses, Coxsackie viruses, and vaccinia viruses – have been applied as either naturally occurring or engineered vectors. Numerous studies in animal-tumor models have demonstrated substantial tumor regression and prolonged survival rates. Moreover, clinical trials have confirmed good safety profiles and therapeutic efficacy for oncolytic viruses. Most encouragingly, the first cancer gene-therapy drug – Gendicine, based on oncolytic adenovirus type 5 – was approved in China. Likewise, a second-generation oncolytic herpes simplex virus-based drug for the treatment of melanoma has been registered in the US and Europe as talimogene laherparepvec. Keywords: immunotherapy, viral vectors, clinical trials, drug approval

Complete nucleotide sequence of watermelon chlorotic stunt virus originating from Oman.

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Khan, Akhtar J; Akhtar, Sohail; Briddon, Rob W; Ammara, Um; Al-Matrooshi, Abdulrahman M; Mansoor, Shahid

2012-07-01

Watermelon chlorotic stunt virus (WmCSV) is a bipartite begomovirus (genus Begomovirus, family Geminiviridae) that causes economic losses to cucurbits, particularly watermelon, across the Middle East and North Africa. Recently squash (Cucurbita moschata) grown in an experimental field in Oman was found to display symptoms such as leaf curling, yellowing and stunting, typical of a begomovirus infection. Sequence analysis of the virus isolated from squash showed 97.6-99.9% nucleotide sequence identity to previously described WmCSV isolates for the DNA A component and 93-98% identity for the DNA B component. Agrobacterium-mediated inoculation to Nicotiana benthamiana resulted in the development of symptoms fifteen days post inoculation. This is the first bipartite begomovirus identified in Oman. Overall the Oman isolate showed the highest levels of sequence identity to a WmCSV isolate originating from Iran, which was confirmed by phylogenetic analysis. This suggests that WmCSV present in Oman has been introduced from Iran. The significance of this finding is discussed.

Distribution of mosquitoes and mosquito-borne arboviruses in Yunnan Province near the China-Myanmar-Laos border.

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Wang, Jinglin; Zhang, Hailin; Sun, Xiaohong; Fu, Shihong; Wang, Huanqin; Feng, Yun; Wang, Huanyu; Tang, Qing; Liang, Guo-Dong

2011-05-01

Economic development and increased tourism in the southern region of Yunnan Province in China, adjacent to several countries in Southeast Asia, has increased the likelihood of import and export of vectors and vector-borne diseases. We report the results of surveillance of mosquitoes and mosquito-borne arboviruses along the border of China-Myanmar-Laos in 2005 and 2006, and information associating several arboviruses with infections and possibly disease in local human populations. Seventeen mosquito species representing four genera were obtained, and 14 strains of mosquito-borne viruses representing six viruses in five genera were isolated from Culex tritaeniorhynchus. In addition, IgM against Japanese encephalitis virus, Sindbis virus, Yunnan orbivirus and novel Banna virus was detected in acute-phase serum samples obtained from hospitalized patients with fever and encephalitis near the areas where the viruses were isolated. This investigation suggests that Japanese encephalitis virus, Sindbis virus, and lesser-known arboviruses circulate and may be infecting humans in the China-Myanmar-Laos border region.

Barley yellow dwarf virus: Luteoviridae or Tombusviridae?

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Miller, W Allen; Liu, Sijun; Beckett, Randy

2002-07-01

Summary Barley yellow dwarf virus (BYDV), the most economically important virus of small grains, features highly specialised relationships with its aphid vectors, a plethora of novel translation mechanisms mediated by long-distance RNA interactions, and an ambiguous taxonomic status. The structural and movement proteins of BYDV that confer aphid transmission and phloem-limitation properties resemble those of the Luteoviridae, the family in which BYDV is classified. In contrast, many genes and cis-acting signals involved in replication and gene expression most closely resemble those of the Tombusviridae. BYDV is in genus Luteovirus, family Luteoviridae. BYDV includes at least two serotypes or viruses: BYDV-PAV and BYDV-MAV. The former BYDV-RPV is now Cereal yellow dwarf virus-RPV (CYDV-RPV). CYDV is in genus Polerovirus, family Luteoviridae. Genus Luteovirus shares many features with family Tombusviridae. Physical properties: approximately 25 nm icosahedral (T = 3) virions. One major (22 kDa) and one minor (50-55 kDa) coat protein. 5.6-5.8 kb positive sense RNA genome with no 5'-cap and no poly(A) tail. Most grasses. Most important in oats, barley and wheat. Also infects maize and rice. Yellowing and dwarfing in barley, stunting in wheat; reddening, yellowing and blasting in oats. Some isolates cause leaf notching and curling. Key attractions: Model for the study of circulative transmission of aphid-transmitted viruses. Plethora of unusual translation mechanisms. Evidence of recombination in recent evolutionary history creates taxonomic ambiguity. Economically important virus of wheat, barley and oats, worldwide. Useful websites/meetings: International symposium: 'Barley Yellow Dwarf Disease: Recent Advances and Future Strategies', CIMMYT, El Batan, Mexico, 1-5 September 2002, http://www.cimmyt.cgiar.org/Research/wheat/Conf_BYD_02/invitation.htm http://www.cimmyt.org/Research/wheat/BYDVNEWS/htm/BYDVNEWS.htm Aphid transmission animation: http://www.ppws.vt.edu/~sforza/tmv/bydv_aph.html.

Mimic Phosphorylation of a βC1 Protein Encoded by TYLCCNB Impairs Its Functions as a Viral Suppressor of RNA Silencing and a Symptom Determinant.

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Zhong, Xueting; Wang, Zhan Qi; Xiao, Ruyuan; Cao, Linge; Wang, Yaqin; Xie, Yan; Zhou, Xueping

2017-08-15

Phosphorylation of the βC1 protein encoded by the betasatellite of tomato yellow leaf curl China virus (TYLCCNB-βC1) by SNF1-related protein kinase 1 (SnRK1) plays a critical role in defense of host plants against geminivirus infection in Nicotiana benthamiana However, how phosphorylation of TYLCCNB-βC1 impacts its pathogenic functions during viral infection remains elusive. In this study, we identified two additional tyrosine residues in TYLCCNB-βC1 that are phosphorylated by SnRK1. The effects of TYLCCNB-βC1 phosphorylation on its functions as a viral suppressor of RNA silencing (VSR) and a symptom determinant were investigated via phosphorylation mimic mutants in N. benthamiana plants. Mutations that mimic phosphorylation of TYLCCNB-βC1 at tyrosine 5 and tyrosine 110 attenuated disease symptoms during viral infection. The phosphorylation mimics weakened the ability of TYLCCNB-βC1 to reverse transcriptional gene silencing and to suppress posttranscriptional gene silencing and abolished its interaction with N. benthamiana ASYMMETRIC LEAVES 1 in N. benthamiana leaves. The mimic phosphorylation of TYLCCNB-βC1 had no impact on its protein stability, subcellular localization, or self-association. Our data establish an inhibitory effect of phosphorylation of TYLCCNB-βC1 on its pathogenic functions as a VSR and a symptom determinant and provide a mechanistic explanation of how SnRK1 functions as a host defense factor. IMPORTANCE Tomato yellow leaf curl China virus (TYLCCNV), which causes a severe yellow leaf curl disease in China, is a monopartite geminivirus associated with the betasatellite (TYLCCNB). TYLCCNB encodes a single pathogenicity protein, βC1 (TYLCCNB-βC1), which functions as both a viral suppressor of RNA silencing (VSR) and a symptom determinant. Here, we show that mimicking phosphorylation of TYLCCNB-βC1 weakens its ability to reverse transcriptional gene silencing, to suppress posttranscriptional gene silencing, and to interact with N

Phylogenetic relationships of the glycoprotein gene of bovine ephemeral fever virus isolated from mainland China, Taiwan, Japan, Turkey, Israel and Australia

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Zheng Fuying

2012-11-01

Full Text Available Abstract Background The glycoprotein (G gene sequences of bovine ephemeral fever virus (BEFV strains derived from mainland China have not been compared with those of the isolates from other countries or areas. Therefore, the G genes of four BEFV isolates obtained from mainland China were amplified and sequenced. A phylogenetic tree was constructed in order to compare and analyze the genetic relationships of the BEFV isolates derived from mainland China and different countries and areas. Results The complete BEFV G gene was successfully amplified and sequenced from four isolates that originated from mainland China. A total of fifty-one BEFV strains were analyzed based on the G gene sequence and were found to be highly conserved. A phylogenetic tree showed that the isolates were grouped into three distinct lineages depending on their source of origin. The antigenic sites of G1, G2 and G3 are conserved among the isolates, except for several substitutions in a few strains. Conclusions The phylogenetic relationships of the BEFV isolates that originated from mainland China, Taiwan, Japan, Turkey, Israel and Australia were closely related to their source of origin, while the antigenic sites G1, G2 and G3 are conserved among the BEFV isolates used in this work.

Genetic characterization of H1N2 influenza a virus isolated from sick pigs in Southern China in 2010.

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Kong, Wei Li; Huang, Liang Zong; Qi, Hai Tao; Cao, Nan; Zhang, Liang Quan; Wang, Heng; Guan, Shang Song; Qi, Wen Bao; Jiao, Pei Rong; Liao, Ming; Zhang, Gui Hong

2011-10-13

In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2), was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.

Genetic characterization of H1N2 influenza a virus isolated from sick pigs in Southern China in 2010

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Kong Wei

2011-10-01

Full Text Available Abstract In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2, was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.

A randomised clinical trial of the efficacy of drop squats or leg extension/leg curl exercises to treat clinically diagnosed jumper's knee in athletes: pilot study

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Cannell, L; Taunton, J; Clement, D; Smith, C; Khan, K

2001-01-01

Objectives—To compare the therapeutic effect of two different exercise protocols in athletes with jumper's knee. Methods—Randomised clinical trial comparing a 12 week programme of either drop squat exercises or leg extension/leg curl exercises. Measurement was performed at baseline and after six and 12 weeks. Primary outcome measures were pain (visual analogue scale 1–10) and return to sport. Secondary outcome measures included quadriceps and hamstring moment of force using a Cybex II isokinetic dynamometer at 30°/second. Differences in pain response between the drop squat and leg extension/curl treatment groups were assessed by 2 (group) x 3 (time) analysis of variance. Two by two contingency tables were used to test differences in rates of return to sport. Analysis of variance (2 (injured versus non-injured leg) x 2 (group) x 3 (time)) was also used to determine differences for secondary outcome measures. Results—Over the 12 week intervention, pain diminished by 2.3 points (36%) in the leg extension/curl group and 3.2 points (57%) in the squat group. There was a significant main effect of both exercise protocols on pain (psquat group returned to sporting activity by 12 weeks, but five of those subjects still had low level pain. Six of nine of the leg extension/curl group returned to sporting activity by 12 weeks and four patients had low level pain. There was no significant difference between groups in numbers returning to sporting activity. There were no differences in the change in quadriceps or hamstring muscle moment of force between groups. Conclusions—Progressive drop squats and leg extension/curl exercises can reduce the pain of jumper's knee in a 12 week period and permit a high proportion of patients to return to sport. Not all patients, however, return to sport by that time. Key Words: knee; patellar tendon; tendinopathy; tendinosis; eccentric strengthening; strength training PMID:11157465

Management of whitefly-transmitted viruses in open-field production systems.

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Lapidot, Moshe; Legg, James P; Wintermantel, William M; Polston, Jane E

2014-01-01

Whiteflies are a key pest of crops in open-field production throughout the tropics and subtropics. This is due in large part to the long and diverse list of devastating plant viruses transmitted by these vectors. Open-field production provides many challenges to manage these viruses and in many cases adequate management has not been possible. Diseases caused by whitefly-transmitted viruses have become limiting factors in open-field production of a wide range of crops, i.e., bean golden mosaic disease in beans, tomato yellow leaf curl disease in tomato, cassava mosaic disease and cassava brown streak disease in cassava, and cotton leaf crumple disease in cotton. While host resistance has proven to be the most cost-effective management solution, few examples of host resistance have been developed to date. The main strategy to limit the incidence of virus-infected plants has been the application of insecticides to reduce vector populations aided to some extent by the use of selected cultural practices. However, due to concerns about the effect of insecticides on pollinators, consumer demand for reduced pesticide use, and the ability of the whitefly vectors to develop insecticide-resistance, there is a growing need to develop and deploy strategies that do not rely on insecticides. The reduction in pesticide use will greatly increase the need for genetic resistance to more viruses in more crop plants. Resistance combined with selected IPM strategies could become a viable means to increase yields in crops produced in open fields despite the presence of whitefly-transmitted viruses.

Influenza A(H9N2) Virus, Myanmar, 2014-2015.

Science.gov (United States)

Lin, Thant Nyi; Nonthabenjawan, Nutthawan; Chaiyawong, Supassama; Bunpapong, Napawan; Boonyapisitsopa, Supanat; Janetanakit, Taveesak; Mon, Pont Pont; Mon, Hla Hla; Oo, Kyaw Naing; Oo, Sandi Myint; Mar Win, Mar; Amonsin, Alongkorn

2017-06-01

Routine surveillance of influenza A virus was conducted in Myanmar during 2014-2015. Influenza A(H9N2) virus was isolated in Shan State, upper Myanmar. Whole-genome sequencing showed that H9N2 virus from Myanmar was closely related to H9N2 virus of clade 4.2.5 from China.

Seroprevalence and Risk Factors of Bluetongue Virus Infection in Tibetan Sheep and Yaks in Tibetan Plateau, China.

Science.gov (United States)

Ma, Jian-Gang; Zhang, Xiao-Xuan; Zheng, Wen-Bin; Xu, Ying-Tian; Zhu, Xing-Quan; Hu, Gui-Xue; Zhou, Dong-Hui

2017-01-01

Bluetongue (BT), caused by bluetongue virus (BTV), is an arthropod-borne viral disease in ruminants. However, information about BTV infection in yaks in China is limited. Moreover, no such data concerning BTV in Tibetan sheep is available. Therefore, 3771 serum samples were collected from 2187 Tibetan sheep and 1584 yaks between April 2013 and March 2014 from Tibetan Plateau, western China, and tested for BTV antibodies using a commercially available ELISA kit. The overall seroprevalence of BTV was 17.34% (654/3771), with 20.3% (443/2187) in Tibetan sheep and 13.3% (211/1584) in yaks. In the Tibetan sheep group, the seroprevalence of BTV in Luqu, Maqu, Tianzhu, and Nyingchi Prefecture was 20.3%, 20.8%, 20.5%, and 19.1%, respectively. The seroprevalence of BTV in different season groups varied from 16.5% to 23.4%. In the yak group, BTV seroprevalence was 12.6%, 15.5%, and 11.0% in Tianzhu, Maqu, and Luqu counties, respectively. The seroprevalence in different seasons was 12.6%, 15.5%, 15.4%, and 9.0% in spring, summer, autumn, and winter, respectively. The season was the major risk factor concerning BTV infection in yaks ( P Tibetan sheep and yaks provides baseline information for controlling BT in ruminants in western China.

Analytical solutions of the electrostatically actuated curled beam problem

KAUST Repository

Younis, Mohammad I.

2014-07-24

This works presents analytical expressions of the electrostatically actuated initially deformed cantilever beam problem. The formulation is based on the continuous Euler-Bernoulli beam model combined with a single-mode Galerkin approximation. We derive simple analytical expressions for two commonly observed deformed beams configurations: the curled and tilted configurations. The derived analytical formulas are validated by comparing their results to experimental data and numerical results of a multi-mode reduced order model. The derived expressions do not involve any complicated integrals or complex terms and can be conveniently used by designers for quick, yet accurate, estimations. The formulas are found to yield accurate results for most commonly encountered microbeams of initial tip deflections of few microns. For largely deformed beams, we found that these formulas yield less accurate results due to the limitations of the single-mode approximation. In such cases, multi-mode reduced order models are shown to yield accurate results. © 2014 Springer-Verlag Berlin Heidelberg.

The current incidence of viral disease in korean sweet potatoes and development of multiplex rt-PCR assays for simultaneous detection of eight sweet potato viruses.

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Kwak, Hae-Ryun; Kim, Mi-Kyeong; Shin, Jun-Chul; Lee, Ye-Ji; Seo, Jang-Kyun; Lee, Hyeong-Un; Jung, Mi-Nam; Kim, Sun-Hyung; Choi, Hong-Soo

2014-12-01

Sweet potato is grown extensively from tropical to temperate regions and is an important food crop worldwide. In this study, we established detection methods for 17 major sweet potato viruses using single and multiplex RT-PCR assays. To investigate the current incidence of viral diseases, we collected 154 samples of various sweet potato cultivars showing virus-like symptoms from 40 fields in 10 Korean regions, and analyzed them by RT-PCR using specific primers for each of the 17 viruses. Of the 17 possible viruses, we detected eight in our samples. Sweet potato feathery mottle virus (SPFMV) and sweet potato virus C (SPVC) were most commonly detected, infecting approximately 87% and 85% of samples, respectively. Furthermore, Sweet potato symptomless virus 1 (SPSMV-1), Sweet potato virus G (SPVG), Sweet potato leaf curl virus (SPLCV), Sweet potato virus 2 ( SPV2), Sweet potato chlorotic fleck virus (SPCFV), and Sweet potato latent virus (SPLV) were detected in 67%, 58%, 47%, 41%, 31%, and 20% of samples, respectively. This study presents the first documented occurrence of four viruses (SPVC, SPV2, SPCFV, and SPSMV-1) in Korea. Based on the results of our survey, we developed multiplex RT-PCR assays for simple and simultaneous detection of the eight sweet potato viruses we recorded.

The Current Incidence of Viral Disease in Korean Sweet Potatoes and Development of Multiplex RT-PCR Assays for Simultaneous Detection of Eight Sweet Potato Viruses

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Hae-Ryun Kwak

2014-12-01

Full Text Available Sweet potato is grown extensively from tropical to temperate regions and is an important food crop worldwide. In this study, we established detection methods for 17 major sweet potato viruses using single and multiplex RT-PCR assays. To investigate the current incidence of viral diseases, we collected 154 samples of various sweet potato cultivars showing virus-like symptoms from 40 fields in 10 Korean regions, and analyzed them by RT-PCR using specific primers for each of the 17 viruses. Of the 17 possible viruses, we detected eight in our samples. Sweet potato feathery mottle virus (SPFMV and sweet potato virus C (SPVC were most commonly detected, infecting approximately 87% and 85% of samples, respectively. Furthermore, Sweet potato symptomless virus 1 (SPSMV-1, Sweet potato virus G (SPVG, Sweet potato leaf curl virus (SPLCV, Sweet potato virus 2 ( SPV2, Sweet potato chlorotic fleck virus (SPCFV, and Sweet potato latent virus (SPLV were detected in 67%, 58%, 47%, 41%, 31%, and 20% of samples, respectively. This study presents the first documented occurrence of four viruses (SPVC, SPV2, SPCFV, and SPSMV-1 in Korea. Based on the results of our survey, we developed multiplex RT-PCR assays for simple and simultaneous detection of the eight sweet potato viruses we recorded.

Outbreak of variant pseudorabies virus in Bartha-K61-vaccinated piglets in central Shandong Province, China.

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Hu, Dongfang; Zhang, Zhendong; Lv, Lin; Xiao, Yihong; Qu, Yajin; Ma, Haiying; Niu, Yujuan; Wang, Guangwen; Liu, Sidang

2015-09-01

An epidemic that mainly endangered 3-7-day-old piglets struck many farms in Shandong Province, China in 2013 and caused heavy losses. To identify the pathogenesis, the type of lesions, and the causative agent, systemic examinations were performed. Autopsy showed multiple lesions, including necrotic foci of the spleen and liver, punctate hemorrhage of the renal cortex, and interstitial pneumonia. Histological examinations showed typical nonsuppurative encephalitis, necrotic lymphocytes, and reticuloendothelial cells in lymphatic tissues, as well as eosinophilic inclusion bodies in the nuclei of reticuloendothelial cells, necrotic foci in liver cells, and hemorrhagic glomeruli. The average seroprevalence rate of field pseudorabies virus (PRV; Suid herpesvirus 1) of a representative farm tested by enzyme-linked immunosorbent assay was 46%, indicating that the PRV infectious pressure was quite severe especially among gilts, young multiparous sows, boars, and growing-finishing pigs. The glycoprotein E (gE) gene of PRV was detected in 8 of 10 clinical samples, and the virus in the positive samples induced obvious cytopathic effects. An immunoperoxidase monolayer assay showed that PRV antigens were distributed both in the nucleoli and cytoplasm of infected cells. Sequencing and phylogenetic analysis of the gE gene showed that the strain isolated herein, TaiAn SD 2013, was highly similar to previously isolated strains, especially those isolated in northern China in 2013, and was closely related to other isolates from Asia. Evidence confirmed that the variant PRV was the etiologic agent of this epidemic, suggesting that the Bartha-K61 vaccine does not provide complete protection against PRV infection. Further challenge tests are ongoing to investigate the virulence of variant PRV. © 2015 The Author(s).

Genetic characterization of canine influenza A virus (H3N2) in Thailand.

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Bunpapong, Napawan; Nonthabenjawan, Nutthawan; Chaiwong, Supassama; Tangwangvivat, Ratanaporn; Boonyapisitsopa, Supanat; Jairak, Waleemas; Tuanudom, Ranida; Prakairungnamthip, Duangduean; Suradhat, Sanipa; Thanawongnuwech, Roongroje; Amonsin, Alongkorn

2014-02-01

In January 2012, several clinical cases of dogs with flu-like symptoms, including coughing, sneezing, nasal discharge, and fever, were reported in a small-animal hospital located in Bangkok, Thailand. One influenza A virus was identified and characterized as an avian-like influenza virus H3N2. The virus was named A/canine/Thailand/CU-DC5299/12. A phylogenetic analysis indicated that the canine virus belonged to an avian Eurasian lineage and was genetically related to the canine influenza viruses H3N2 from China and Korea. This canine virus displays a unique genetic signature with two amino acid insertions in the NA protein, which is similar to the canine influenza viruses from eastern China (Zhejiang and Jiangsu). This study constitutes the first report of H3N2 canine influenza virus infection in a small-animal hospital in Thailand.

Serum neutralizing activities from a Beijing homosexual male cohort infected with different subtypes of HIV-1 in China.

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Mingshun Zhang

Full Text Available Protective antibodies play a critical role in an effective HIV vaccine; however, eliciting antibodies to block infection by viruses from diverse genetic subtypes remains a major challenge. As the world's most populous country, China has been under the threat of at least three major subtypes of circulating HIV-1 viruses. Understanding the cross reactivity and specificities of serum antibody responses that mediate broad neutralization of the virus in HIV-1 infected Chinese patients will provide valuable information for the design of vaccines to prevent HIV-1 transmission in China. Sera from a cohort of homosexual men, who have been managed by a major HIV clinical center in Beijing, China, were analyzed for cross-sectional neutralizing activities against pseudotyped viruses expressing Env antigens of the major subtype viruses (AE, BC and B subtypes circulating in China. Neutralizing activities in infected patients' blood were most capable of neutralizing viruses in the homologous subtype; however, a subset of blood samples was able to achieve broad neutralizing activities across different subtypes. Such cross neutralizing activity took 1-2 years to develop and CD4 binding site antibodies were critical components in these blood samples. Our study confirmed the presence of broadly neutralizing sera in China's HIV-1 patient population. Understanding the specificity and breadth of these neutralizing activities can guide efforts for the development of HIV vaccines against major HIV-1 viruses in China.

Emerging of two new subgenotypes of porcine reproductive and respiratory syndrome viruses in Southeast China.

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Zhang, Qiaoya; Xu, Xiaojie; You, Shumei; Li, Yufeng; Wang, Haiyan; Bai, Juan; Jiang, Ping

2016-08-01

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the leading swine pathogens and causes major economic loss to the global swine industry. In this study, a total of 49 PRRSV isolates were collected from different swine herds in seven provinces in Southeast China from 2014 to 2015. All the ORF5 genes and some Nsp2 genes were sequenced. Phylogenetic analysis showed that all the isolates belonged to the North America genotype. Among them, five isolates formed a new subgenotype IV derived from highly pathogenic PRRSV (HP-PRRSV). Six isolates formed subgenotype III, which were closely related to the NADC30 strain in the US. These isolates formed 13 putative N-linked glycosylation site (NGS) patterns based on N30, 33, 34, 35, 44 and 51. There were fewer NGSs of isolates in subgenotype IV than in subgenotype III. This indicates that the two new subgenotypes of PRRSV strains with different NGS patterns were spreading in those regions of China. The genetic diversity should be considered for the control and prevention of this disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

History and Current Status of Development and Use of Viral Insecticides in China

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Xiulian Sun

2015-01-01

Full Text Available The use of insect viruses as biological control agents started in the early 1960s in China. To date, more than 32 viruses have been used to control insect pests in agriculture, forestry, pastures, and domestic gardens in China. In 2014, 57 products from 11 viruses were authorized as commercial viral insecticides by the Ministry of Agriculture of China. Approximately 1600 tons of viral insecticidal formulations have been produced annually in recent years, accounting for about 0.2% of the total insecticide output of China. The development and use of Helicoverpa armigera nucleopolyhedrovirus, Mamestra brassicae nucleopolyhedrovirus, Spodoptera litura nucleopolyhedrovirus, and Periplaneta fuliginosa densovirus are discussed as case studies. Additionally, some baculoviruses have been genetically modified to improve their killing rate, infectivity, and ultraviolet resistance. In this context, the biosafety assessment of a genetically modified Helicoverpa armigera nucleopolyhedrovirus is discussed.

Annual economic burden of hepatitis B virus-related diseases among hospitalized patients in twelve cities in China.

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Zhang, S; Ma, Q; Liang, S; Xiao, H; Zhuang, G; Zou, Y; Tan, H; Liu, J; Zhang, Y; Zhang, L; Feng, X; Xue, L; Hu, D; Cui, F; Liang, X

2016-03-01

A nationwide survey of hepatitis B virus (HBV)-associated economic burden has not previously been performed in China. The purpose of this study was to examine the direct, indirect, and intangible costs of HBV-related diseases within the span of one year. A random sample was taken from specialty and general hospitals across 12 cities in six provinces of China. Intangible costs were estimated based on willingness to pay or open-ended answers provided by patients. The results showed that 27 hospitals were enrolled, with a sample population of 4726 patients (77.7% response rate). The average annual costs were $4454.0 (direct), $924.3 (indirect), and $6611.10 (intangible), corresponding to 37.3%, 7.7%, and 55.1% of the total costs, respectively. The direct medical fees were substantially greater than the non-medical fees. Annual indirect costs were divided into outpatient ($112.9) and inpatient ($811.40) loss of income. The intangible costs of chronic HBV were notably higher than either the direct or indirect costs, consistent with the social stigma in China. The comparison amongst individual cities for the average ratio of direct to indirect costs revealed that the sizes of ratios were negatively correlated with the socioeconomic status of the regions. This study suggested that as a whole in China, the HBV-related diseases caused a heavy financial burden which was positively associated with disease severity. Although the intangible costs coincided with a high prevalence of discrimination against CHB patients in Chinese society, our study may serve as future reference for detailed exploration. © 2015 John Wiley & Sons Ltd.

Molecular and biological characterisation of two novel pomo-like viruses associated with potato (Solanum tuberosum) fields in Colombia.

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Gil, Jose Fernando; Adams, Ian; Boonham, Neil; Nielsen, Steen Lykke; Nicolaisen, Mogens

2016-06-01

Potato is the fourth most important crop worldwide that is used as a staple food, after rice, wheat and maize. The crop can be affected by a large number of pathogens, including fungi, oomycetes, bacteria and viruses. Diseases caused by viruses are among the most important factors contributing to reduced quality and yield of the crop. Potato mop-top virus (genus Pomovirus) induces necrotic flecks in the tuber flesh and skin of potato in temperate countries. Spongospora subterranea is the vector of PMTV. Both the virus and its vector cause disease in potato. In Colombia, PMTV has been detected throughout the country together with a novel pomo-like virus in the centre (Cundinamarca and Boyacá) and south west (Nariño) of the country. We studied the molecular and biological characteristics of this novel virus. Its genome resembles those of members of the genus Pomovirus, and it is closely related to PMTV. It induces mild systemic symptoms in Nicotiana benthamiana (mosaic, branch curling), but no symptoms in N. tabacum, N. debneyi and Chenopodium amaranticolor. The proposed name for the virus is "Colombian potato soil-borne virus" (CPSbV). Additionally, another pomo-like virus was identified in Nariño. This virus induces severe systemic stem declining and mild mosaic in N. benthamiana. The tentative name "soil-borne virus 2" (SbV2) is proposed for this virus. No vectors have been identified for these viruses despite several attempts. This work focused on the characterisation of CPSbV. The risk posed by these viruses if they are introduced into new territories is discussed.

Molecular and antigenic characteristics of Newcastle disease virus isolates from domestic ducks in China.

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Wu, Wei; Liu, Huairan; Zhang, Tingting; Han, Zongxi; Jiang, Yanyu; Xu, Qianqian; Shao, Yuhao; Li, Huixin; Kong, Xiangang; Chen, Hongyan; Liu, Shengwang

2015-06-01

Newcastle disease (ND) is one of the most devastating diseases to the poultry industry. The causative agents of ND are virulent strains of Newcastle disease virus (NDV), which are members of the genus Avulavirus within the family Paramyxoviridae. Waterfowl, such as ducks and geese, are generally considered potential reservoirs of NDV and may show few or no clinical signs when infected with viruses that are obviously virulent in chickens. However, ND outbreaks in domestic waterfowl have been frequently reported in many countries in the past decade. In this study, 18 NDV strains isolated from domestic ducks in southern and eastern China, between 2005 and 2013, were genetically and phylogenetically characterized. The complete genomes of these strains were sequenced, and they exhibited genome sizes of 15,186 nucleotides (nt), 15,192 nt, and 15,198 nt, which follow the "rule of six" that is required for the replication of NDV strains. Based on the cleavage site of the F protein and pathogenicity tests in chickens, 17 of our NDV isolates were categorized as lentogenic viruses, and one was characterized as a velogenic virus. Phylogenetic analysis based on the partial sequences of the F gene and the complete genome sequences showed that there are at least four genotypes of NDV circulating in domestic ducks; GD1, AH224, and AH209 belong to genotypes VIId, Ib, and II of class II NDVs, respectively, and the remaining 15 isolates belong to genotype 1b of class I NDVs. Cross-reactive hemagglutination inhibition tests demonstrated that the antigenic relatedness between NDV strains may be associated with their genotypes, rather than their hosts. These results suggest that though those NDV isolates were from duck, they still don't form a phylogenetic group because they came from the same species; however, they may play an important role in promoting the evolution of NDVs. Copyright © 2015 Elsevier B.V. All rights reserved.

Direct economic burden of hepatitis B virus related diseases: evidence from Shandong, China

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Lu Jingjing

2013-01-01

Full Text Available Abstract Background Although the expenses of liver cirrhosis are covered by a critical illness fund under the current health insurance program in China, the economic burden associated with hepatitis B virus (HBV related diseases is not well addressed. In order to provide evidence to address the economic disease burden of HBV, we conducted a survey to investigate the direct economic burden of acute and chronic hepatitis B, cirrhosis and liver cancer caused by HBV-related disease. Methods From April 2010 to November 2010, we conducted a survey of inpatients with HBV-related diseases and who were hospitalized for seven or more days in one of the seven tertiary and six secondary hospitals in Shandong, China. Patients were recorded consecutively within a three-to-five month time period from each sampled hospital; an in-person survey was conducted to collect demographic and socio-economic information, as well as direct medical and nonmedical expenses during the last month and last year prior to the current hospitalization. Direct medical costs included total outpatient, inpatient, and self-treatment expenditures; direct nonmedical costs included spending on nutritional supplements, transportation, and nursing. Direct medical costs during the current hospitalization were also obtained from the hospital financial database. The direct economic cost was calculated as the sum of direct medical and nonmedical costs. Our results call for the importance of implementing clinical guideline, improving system accountability, and helping secondary and smaller hospitals to improve efficiency. This has important policy implication for the on-going hospital reform in China. Results Our data based on inpatients with HBV-related diseases suggested that the direct cost in US dollars for acute hepatitis B, severe hepatitis B, chronic hepatitis B, compensated cirrhosis, decompensated cirrhosis and primary liver cancer was $2954, $10834, $4552, $7400.28, $6936 and $10635

Direct economic burden of hepatitis B virus related diseases: evidence from Shandong, China.

Science.gov (United States)

Lu, Jingjing; Xu, Aiqiang; Wang, Jian; Zhang, Li; Song, Lizhi; Li, Renpeng; Zhang, Shunxiang; Zhuang, Guihua; Lu, Mingshan

2013-01-31

Although the expenses of liver cirrhosis are covered by a critical illness fund under the current health insurance program in China, the economic burden associated with hepatitis B virus (HBV) related diseases is not well addressed. In order to provide evidence to address the economic disease burden of HBV, we conducted a survey to investigate the direct economic burden of acute and chronic hepatitis B, cirrhosis and liver cancer caused by HBV-related disease. From April 2010 to November 2010, we conducted a survey of inpatients with HBV-related diseases and who were hospitalized for seven or more days in one of the seven tertiary and six secondary hospitals in Shandong, China. Patients were recorded consecutively within a three-to-five month time period from each sampled hospital; an in-person survey was conducted to collect demographic and socio-economic information, as well as direct medical and nonmedical expenses during the last month and last year prior to the current hospitalization. Direct medical costs included total outpatient, inpatient, and self-treatment expenditures; direct nonmedical costs included spending on nutritional supplements, transportation, and nursing. Direct medical costs during the current hospitalization were also obtained from the hospital financial database. The direct economic cost was calculated as the sum of direct medical and nonmedical costs. Our results call for the importance of implementing clinical guideline, improving system accountability, and helping secondary and smaller hospitals to improve efficiency. This has important policy implication for the on-going hospital reform in China. Our data based on inpatients with HBV-related diseases suggested that the direct cost in US dollars for acute hepatitis B, severe hepatitis B, chronic hepatitis B, compensated cirrhosis, decompensated cirrhosis and primary liver cancer was $2954, $10834, $4552, $7400.28, $6936 and $10635, respectively. These costs ranged from 30.72% (for acute

Seroprevalence of avian influenza A (H5N1 virus among poultry workers in Jiangsu Province, China: an observational study

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Huo Xiang

2012-04-01

Full Text Available Abstract Background Since 2003 to 06 Jan 2012, the number of laboratory confirmed human cases of infection with avian influenza in China was 41 and 27 were fatal. However, the official estimate of the H5N1 case-fatality rate has been described by some as an over estimation since there may be numerous undetected asymptomatic/mild cases of H5N1 infection. This study was conducted to better understand the real infection rate and evaluate the potential risk factors for the zoonotic spread of H5N1 viruses to humans. Methods A seroepidemiological survey was conducted in poultry workers, a group expected to have the highest level of exposure to H5N1-infected birds, from 3 counties with habitat lakes of wildfowl in Jiangsu province, China. Serum specimens were collected from 306 participants for H5N1 serological test. All participants were interviewed to collect information about poultry exposures. Results The overall seropositive rate was 2.61% for H5N1 antibodies. The poultry number was found associated with a 2.39-fold significantly increased subclinical infection risk after adjusted with age and gender. Conclusions Avian-to -human transmission of avian H5N1 virus remained low. Workers associated with raising larger poultry flocks have a higher risk on seroconversion.

[Detection of Avian Influenza Virus in Environmental Samples Collected from Live Poultry Markets in China during 2009-2013].

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Zhang, Ye; Li, Xiaodan; Zou, Shumei; Bo, Hong; Dong, Libo; Gao, Rongbao; Wang, Dayan; Shu, Yuelong

2015-11-01

Abstract: To investigate the distribution of avian influenza virus in environmental samples from live poultry markets (LPM) in China, samples were collected and tested by nucleic acid during 2009-2013 season. Each sample was tested by real-time RT PCR using flu A specific primers. If any real-time PCR was positive, the sample was inoculated into specific-pathogen-free (SPF) embryonated chicken eggs for viral isolation. The results indicated that the positive rate of nucleic acid in enviromental samples exhibited seasonality. The positive rate of nucleic acid was significantly higher in Winter and Spring. The positive rate of nucleic acid in LPM located in the south of China was higher than in northern China. Samples of Sewage for cleaning poultry and chopping board showed that higher positive rate of nucleic acid than other samples. The Subtype identification showed that H5 and H9 were main subtypes in the enviromental samples. Viral isolation indicated H5 subtypes was more than H9 subtypes between 2009 and 2013 while H9 subtypes increased in 2013. Our findings suggested the significance of public health based on LPM surveillance and provided the basis of prevention and early warning for avian flu infection human.

[Swine influenza virus: evolution mechanism and epidemic characterization--a review].

Science.gov (United States)

Qi, Xian; Lu, Chengping

2009-09-01

Pigs may play an important role in the evolution and ecology of influenza A virus. The tracheal epithelium of pigs contain both SA alpha 2,6 Gal and SA alpha 2,3 Gal receptors and can be infected with swine, human and avian viruses, therefore, pigs have been considered as an intermediate host for the adaptation of avian influenza viruses to humans or as mixing vessels for the generation of genetically reassortant viruses. Evolution patterns among swine influenza viruses including evolution of host adaptation, antigenic drift and genetic reassortment, and the latter is the main one. Unlike human influenza viruses, swine viruses have different epizootiological patterns in different areas of world, which is enzootic and geographic dependence. Currently, three predominant subtypes of influenza virus are prevalent in pig populations worldwide: H1N1, H3N2, and H1N2, and these include classical swine H1N1, avian-like H1N1, human-like H3N2, reassortant H3N2 and various genotype H1N2 viruses. In Europe, North America and China, influenza A viruses circulating in pigs are distinct in the genetic characteristics and genetic sources. Since 1979, three subtypes, avian-like H1N1, reassortant H1N2 and H3N2 viruses, have been co-circulating in European swine. Before 1998, classical H1N1 viruses were the exclusive cause of swine influenza in North America. However, after that, three triple-reassortant H1N2, H3N2 and H1N1 viruses with genes of human, swine and avian virus began to emerge in pigs. Genetically, the pandemic viruses emerging in human, so called influenza A (H1N1) viruses, contain genes from both Europe and North American SIV lineages. SIV is not the same as Europe and the United States in the prevalence and genetic background in China, mainly classical swine H1N1 and human-like H3N2 type virus. However, in recent years, SIV from Europe and North America have been introduced into Chinese pig herds, so more attention should be given on the evolutionary of SIV in China

Vector competence of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) for the DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus in Fujian, China.

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Guo, Xiao-Xia; Li, Chun-Xiao; Zhang, Ying-Mei; Xing, Dan; Dong, Yan-De; Zhang, Heng-Duan; Qin, Cheng-Feng; Zhao, Tong-Yan

2016-09-01

Dengue is an acute, emerging, infectious disease transmitted by Aedes mosquitoes that has become a serious global public health problem. The DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus were originally isolated from the serum of a patient with dengue fever in Fujian Province, China, in 1999. Our data provide the first assessment of the vector competence of Aedes mosquitoes with respect to the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus. There were significant differences in the replication rates of these two viral strains in Aedes albopictus and Aedes aegypti (P0.05). In summary, our results indicate that Ae. albopictus and Ae. aegypti mosquitoes are moderately competent vectors of the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus and provide the first evidence of the effect of these two viral strains on the vector competence of mosquitoes in China. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparative epidemiology of human infections with avian influenza A H7N9 and H5N1 viruses in China: a population-based study of laboratory-confirmed cases.

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Cowling, Benjamin J; Jin, Lianmei; Lau, Eric H Y; Liao, Qiaohong; Wu, Peng; Jiang, Hui; Tsang, Tim K; Zheng, Jiandong; Fang, Vicky J; Chang, Zhaorui; Ni, Michael Y; Zhang, Qian; Ip, Dennis K M; Yu, Jianxing; Li, Yu; Wang, Liping; Tu, Wenxiao; Meng, Ling; Wu, Joseph T; Luo, Huiming; Li, Qun; Shu, Yuelong; Li, Zhongjie; Feng, Zijian; Yang, Weizhong; Wang, Yu; Leung, Gabriel M; Yu, Hongjie

2013-07-13

The novel influenza A H7N9 virus emerged recently in mainland China, whereas the influenza A H5N1 virus has infected people in China since 2003. Both infections are thought to be mainly zoonotic. We aimed to compare the epidemiological characteristics of the complete series of laboratory-confirmed cases of both viruses in mainland China so far. An integrated database was constructed with information about demographic, epidemiological, and clinical variables of laboratory-confirmed cases of H7N9 (130 patients) and H5N1 (43 patients) that were reported to the Chinese Centre for Disease Control and Prevention until May 24, 2013. We described disease occurrence by age, sex, and geography, and estimated key epidemiological variables. We used survival analysis techniques to estimate the following distributions: infection to onset, onset to admission, onset to laboratory confirmation, admission to death, and admission to discharge. The median age of the 130 individuals with confirmed infection with H7N9 was 62 years and of the 43 with H5N1 was 26 years. In urban areas, 74% of cases of both viruses were in men, whereas in rural areas the proportions of the viruses in men were 62% for H7N9 and 33% for H5N1. 75% of patients infected with H7N9 and 71% of those with H5N1 reported recent exposure to poultry. The mean incubation period of H7N9 was 3·1 days and of H5N1 was 3·3 days. On average, 21 contacts were traced for each case of H7N9 in urban areas and 18 in rural areas, compared with 90 and 63 for H5N1. The fatality risk on admission to hospital was 36% (95% CI 26-45) for H7N9 and 70% (56-83%) for H5N1. The sex ratios in urban compared with rural cases are consistent with exposure to poultry driving the risk of infection--a higher risk in men was only recorded in urban areas but not in rural areas, and the increased risk for men was of a similar magnitude for H7N9 and H5N1. However, the difference in susceptibility to serious illness with the two different viruses

Human immunodeficiency virus/human parvovirus B19 co-infection in blood donors and AIDS patients in Sichuan, China

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He, Miao; Zhu, Jiang; Yin, Huimin; Ke, Ling; Gao, Lei; Pan, Zhihong; Yang, Xiuhua; Li, Wuping

2012-01-01

Background Human parvovirus B19 (B19) is a common pathogen which causes a variety of diseases. Persistent B19 infection is related to the degree of host immunodeficiency in patients with human immunodeficiency virus (HIV) infection. However, the existence, loading, virus evolution and distribution of B19 in Chinese HIV-positive patients have not been determined. Materials and methods. We investigated 573 HIV-positive blood donors and AIDS patients in Sichuan, China in the last two decades. Bl9-specific serology and quantitative polymerase chain reaction were used to determine the prevalence of B19/HIV co-infection. Viral genome fragments were subjected to phylogeny and haplotype analysis. Results B19 genomic DNA was found in 26 of 573 (4.5%) HIV-positive individuals, a higher prevalence than in blood donors. DNA levels ranged from 5.3×102–1.1×105 copies/mL. The seroprevalence of IgG was significantly lower in HIV-positive samples than in HIV-negative blood donors, indicating deficient production of B19-specific IgG in the former. The B19 isolates were genotype-1 subtype B19-1A which formed a monophyletic group; seven distinct haplotypes were discovered with 60% of the B19/HIV co-infected variants sharing one central haplotype. Discussion. This study on the prevalence, phylogeny and distribution of human parvovirus B19 in Sichuan, China, demonstrates the persistence of B19 in the circulation of both immunocompetent and immunocompromised subjects, with implications for blood safety. PMID:22790259

Isolation and sequence characterization of DNA-A genome of a new begomovirus strain associated with severe leaf curling symptoms of Jatropha curcas L.

KAUST Repository

Chauhan, Sushma; Rahman, Hifzur; Mastan, Shaik G.; Sudheer, Pamidimarri D.V.N.; Reddy, Muppala P.

2018-01-01

Begomoviruses belong to the family Geminiviridae are associated with several disease symptoms, such as mosaic and leaf curling in Jatropha curcas. The molecular characterization of these viral strains will help in developing management strategies

Identification of a monopartite begomovirus associated with yellow vein mosaic of Mentha longifolia in Saudi Arabia.

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Sohrab, Sayed Sartaj; Daur, Ihsanullah

2018-02-01

Mentha is a very important crop grown and used extensively for many purposes in the Kingdom of Saudi Arabia. Begomoviruses are whitefly-transmitted viruses causing serious disease in many important plants exhibiting variable symptoms with significant economic loss globally. During farmers' field survey, yellow vein mosaic disease was observed in Mentha longifolia plants growing near tomato fields in Saudi Arabia. The causative agent was identified in 11 out of 19 samples using begomovirus-specific primers and the association of begomovirus with yellow vein mosaic disease in M. longifolia was confirmed. The full-length viral genome and betasatellite were amplified, cloned, and sequenced bidirectionally. The full DNA-A genome was found to have 2785 nucleotides with 1365 bp-associated betasatellite molecule. An attempt was made to amplify DNA-B, but none of the samples produced any positive amplicon of expected size which indicated the presence of monopartite begomovirus. The sequence identity matrix and phylogenetic analysis, based on full genome showed the highest identity (99.6%) with Tomato yellow leaf curl virus (TYLCV) and in phylogenetic analysis it formed a closed cluster with Tomato leaf curl virus infecting tomato and Corchorus crop in Saudi Arabia. The sequence analysis results of betasatellites showed the highest identity (98.9%) with Tomato yellow leaf curl betasatellites infecting tomato and phylogenetic analysis using betasatellites formed a close cluster with Tomato yellow leaf curl betasatellites infecting tomato and Corchorus crops, which has already been reported to cause yellow vein mosaic and leaf curl disease in many cultivated and weed crops growing in Saudi Arabia. The identified begomovirus associated with yellow vein mosaic disease in mentha could be a mutated strain of TYLCV and tentatively designated as TYLCV-Mentha isolate. Based on published data and latest information, this is the first report of identification of Tomato yellow leaf

Decline in the risk of hepatitis A virus infection in China, a country with booming economy and changing lifestyles.

Science.gov (United States)

Xu, Zhi-Yu; Wang, Xuan-Yi; Liu, Chang-Qing; Li, Yang-Ting; Zhuang, Fang-Chen

2008-10-01

The objective of the study was to identify the protective factors for the rapid decline in the risk of hepatitis A virus (HAV) infection in China between 1990 and 2006. Results of serological follow-up and data on annual hepatitis A incidence were analysed and correlated with economic growth and HAV vaccine output during the same period. In conclusion, both HAV vaccination and changing lifestyles associated with the booming economy contributed to the rapid risk decline. Changing lifestyles played a major role in the decline especially in the areas with booming economy.

CHILI: China Lijiang IFU

Science.gov (United States)

Hao, Lei

2014-07-01

Wide-field IFU technology on medium-size telescope provides a unique science capability that compliments larger future facilities. Here I introduce a program to employ a VIRUS-like unit on the 2.4 meter telescope in GaoMeiGu Observatory in LiJiang, China. We name the instrument "CHILI (China Lijiang IFU)". It will be an IFU with very large field of view at 1.8'x3.6'. We discuss its science capabilities and its potential benefit to the Chinese astronomical community.

Human infection and environmental contamination with Avian Influenza A (H7N9) Virus in Zhejiang Province, China: risk trend across the three waves of infection.

Science.gov (United States)

He, Fan; Chen, En-Fu; Li, Fu-Dong; Wang, Xin-Yi; Wang, Xiao-Xiao; Lin, Jun-Fen

2015-09-21

The third wave of H7N9 cases in China emerged in the second half of 2014. This study was conducted to identify the risk trends of H7N9 virus in human infections and environment contamination. A surveillance program for H7N9 virus has been conducted in all 90 counties in Zhejiang since March 2013. All H7N9 cases were reported by hospitals through the China Information System for Disease Control and Prevention. Sampling sites for environment specimens were randomly selected by a multi-stage sampling strategy. Poultry-related workers for serological surveillance were randomly selected from the sampling sites for environmental specimens in the first quarter of each year. rRT-PCR and viral isolation were performed to identify H7N9 virus. A hemagglutination inhibition assay was conducted to detect possible H7N9 infection among poultry-related workers. A total of 170 H7N9 cases were identified in Zhejiang from 20 March 2013 to 28 February 2015. The proportion of rural cases increased from 42.2% (19/45) to 67.7% (21/31) with progression of the three epidemics (P markets in the territory. Poultry operations in slaughtering plants must be supervised rigorously. Prior to the closure of live poultry markets, daily cleaning and disinfecting of areas potentially contaminated by H7N9 virus, centralized collection and disposal of trash, designating certain days as market rest days, banning overnight poultry storage and other measures should be strictly carried out in both urban and rural areas.

Fatal disease associated with Swine Hepatitis E virus and Porcine circovirus 2 co-infection in four weaned pigs in China

OpenAIRE

Yang, Yifei; Shi, Ruihan; She, Ruiping; Mao, Jingjing; Zhao, Yue; Du, Fang; Liu, Can; Liu, Jianchai; Cheng, Minheng; Zhu, Rining; Li, Wei; Wang, Xiaoyang; Soomro, Majid Hussain

2015-01-01

Background In recent decades, Porcine circovirus 2 (PCV2) infection has been recognized as the causative agent of postweaning multisystemic wasting syndrome, and has become a threat to the swine industry. Hepatitis E virus (HEV) is another high prevalent pathogen in swine in many regions of the world. PCV2 and HEV are both highly prevalent in pig farms in China. Case presentation In this study, we characterized the HEV and PCV2 co-infection in 2?3 month-old piglets, based on pathogen identifi...

Genomic Characterization of Travel-Associated Dengue Viruses Isolated from the Entry-Exit Ports in Fujian Province, China, 2013-2015.

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Gao, Bo; Zhang, Jianming; Wang, Yuping; Chen, Fan; Zheng, Chaohui; Xie, Lianhui

2017-09-25

Over the past decade, indigenous dengue outbreaks have occurred occasionally in Fujian province in southeastern China because of sporadic imported dengue viruses (DENV). In this study, 3 DENV-2 and 2 DENV-4 strains were isolated from suspected febrile travelers at 2 ports of entry in Fujian between 2013-2015. Complete viral genome sequences of these new isolates were obtained with Sanger chemistry. Genomic sequence analyses revealed that these strains belonged to genotypes of 2-Cosmopolitan and 4-II. Consistent with the patients' travel information, phylogenetic analyses of the complete coding regions also indicated that most of the new isolates were genetically similar to the circulating strains in Southeast Asia rather than previous Chinese strains that were available. Therefore, phylogenetic analyses of the imported DENV demonstrated that multiple introductions of DENV emerged continuously in Fujian, and highlighted the importance of dengue surveillance at entry-exit ports in the subtropical regions of southern China.

Isolates of Liao ning virus from wild-caught mosquitoes in the Xinjiang province of China in 2005.

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Xinjun Lv

Full Text Available Liao ning virus (LNV is related to Banna virus, a known human-pathogen present in south-east Asia. Both viruses belong to the genus Seadornavirus, family Reoviridae. LNV causes lethal haemorrhage in experimentally infected mice. Twenty seven isolates of LNV were made from mosquitoes collected in different locations within the Xinjiang province of north-western China during 2005. These mosquitoes were caught in the accommodation of human patients with febrile manifestations, or in animal barns where sheep represent the main livestock species. The regions where LNV was isolated are affected by seasonal encephalitis, but are free of Japanese encephalitis (JE. Genome segment 10 (Seg-10 (encoding cell-attachment and serotype-determining protein VP10 and Seg-12 (encoding non-structural protein VP12 were sequenced for multiple LNV isolates. Phylogenetic analyses showed a less homogenous Seg-10 gene pool, as compared to segment 12. However, all of these isolates appear to belong to LNV type-1. These data suggest a relatively recent introduction of LNV into Xinjiang province, with substitution rates for LNV Seg-10 and Seg-12, respectively, of 2.29×10(-4 and 1.57×10(-4 substitutions/nt/year. These substitution rates are similar to those estimated for other dsRNA viruses. Our data indicate that the history of LNV is characterized by a lack of demographic fluctuations. However, a decline in the LNV population in the late 1980s-early 1990s, was indicated by data for both Seg-10 and Seg-12. Data also suggest a beginning of an expansion in the late 1990s as inferred from Seg-12 skyline plot.

Characterization of the complete genome of euonymus yellow vein associated virus, a distinct member of the genus Potexvirus, family Alphaflexiviridae, isolated from Euonymus bungeanus Maxim in Liaoning, Northern China.

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Yang, Caixia; Han, Tong; Fu, Jingjing; Liao, Yiming; Chen, Sha

2018-02-01

In August 2016, a yellow vein disease was observed on leaves of Euonymus bungeanus Maxim (Euonymus, Celastraceae) in Liaoning, China. Virions measuring 750 × 13 nm were observed in a sample from the diseased plant. A potexvirus was detected in the sample by small-RNA deep sequencing analysis and recovered by traditional cloning. The genome of this potexvirus consists of 7,279 nucleotides, excluding the poly(A) tail at the 3' end, and contains five open reading frames (ORFs). Based on the nucleotide and amino acid sequences of the coat protein gene, the virus shared the highest sequence similarity with white clover mosaic virus (WCMV, X16636) (40.1%) and clover yellow mosaic virus (ClYMV, D00485) (37.1%). Phylogenetic analysis showed that the virus clustered with potexviruses and is most closely related to strawberry mild yellow edge virus. These results indicate that this virus is a distinct member of the genus Potexvirus, for which the name euonymus yellow vein associated virus (EuYVAV) is proposed. To our knowledge, this is the first report of a potexvirus on E. bungeanus.

Diversity and evolution of avian influenza viruses in live poultry markets, free-range poultry and wild wetland birds in China.

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Chen, Liang-Jun; Lin, Xian-Dan; Guo, Wen-Ping; Tian, Jun-Hua; Wang, Wen; Ying, Xu-Hua; Wang, Miao-Ruo; Yu, Bin; Yang, Zhan-Qiu; Shi, Mang; Holmes, Edward C; Zhang, Yong-Zhen

2016-04-01

The wide circulation of novel avian influenza viruses (AIVs) highlights the risk of pandemic influenza emergence in China. To investigate the prevalence and genetic diversity of AIVs in different ecological contexts, we surveyed AIVs in live poultry markets (LPMs), free-range poultry and the wetland habitats of wild birds in Zhejiang and Hubei provinces. Notably, LPMs contained the highest frequency of AIV infection, and the greatest number of subtypes (n = 9) and subtype co-infections (n = 14), as well as frequent reassortment, suggesting that they play an active role in fuelling AIV transmission. AIV-positive samples were also identified in wild birds in both provinces and free-range poultry in one sampling site close to a wetland region in Hubei. H9N2, H7N9 and H5N1 were the most commonly sampled subtypes in the LPMs from Zhejiang, whilst H5N6 and H9N2 were the dominant subtypes in the LPMs from Hubei. Phylogenetic analyses of the whole-genome sequences of 43 AIVs revealed that three reassortant H5 subtypes were circulating in LMPs in both geographical regions. Notably, the viruses sampled from the wetland regions and free-range poultry contained complex reassortants, for which the origins of some segments were unclear. Overall, our study highlights the extent of AIV genetic diversity in two highly populated parts of central and south-eastern China, particularly in LPMs, and emphasizes the need for continual surveillance.

Genome characterization of a porcine circovirus type 3 in South China.

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Shen, H; Liu, X; Zhang, P; Wang, L; Liu, Y; Zhang, L; Liang, P; Song, C

2018-02-01

Porcine circovirus type 3 (PCV3) is a novel circovirus that was associated with porcine dermatitis and nephropathy syndrome, reproductive failure, and multisystemic inflammation. Recently, a PCV3 strain was identified from pyretic and pneumonic piglets in Guangdong province, China. This virus strain was sequenced and designated PCV3-China/GD2016. The complete genome of PCV3-China/GD2016 is 2,000 bp in length and shared 99.1% and 99.1% nucleotide identities with PCV3/29160 and PCV3/2164, respectively. [Corrections added after initial online publication on 13 March 2017: The numbers '98.5%' and '97.4%' has been changed to '99.1%' and '99.1%' in the previous sentence.] Phylogenetic analysis based on the complete genome showed that PCV3-China/GD2016 clustered with the emerging PCV3 and separated with other virus in genus Circovirus. The results of this study suggest that PCV3 has existed within the pigs of China. It is urgent to investigate the pathogenicity and epidemiology of this novel circovirus China. © 2017 Blackwell Verlag GmbH.

Emergence of dengue virus 4 genotype II in Guangzhou, China, 2010: Survey and molecular epidemiology of one community outbreak

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Jing Qin-Long

2012-04-01

Full Text Available Abstract Background The re-emergence of dengue virus 4 (DENV-4 has become a public health concern in South America, Southeast Asia and South Asia. However, it has not been known to have caused a local outbreak in China for the past 20 years. The purpose of this study was to elucidate the epidemiology of one local community outbreak caused by DENV-4 in Guangzhou city, China, in 2010; and to determine the molecular characteristics of the genotype II virus involved. Case presentations During September and October of 2010, one imported case, a Guangzhou resident who travelled back from Thailand, resulted in 18 secondary autochthonous cases in Guangzhou City, with an incidence rate of 5.53 per 10,000 residents. In indigenous cases, 14 serum samples tested positive for IgM against DENV and 7 for IgG from a total of 15 submitted serum samples, accompanied by 5 DENV-4 isolates. With identical envelope gene nucleotide sequences, the two isolates (D10168-GZ from the imported index case and Guangzhou 10660 from the first isolate in the autochthonous cases were grouped into DENV-4 genotype II after comparison to 32 previous DENV-4 isolates from GenBank that originated from different areas. Conclusions Based on epidemiological and phylogenetic analyses, the outbreak, which was absent for 20 years after the DENV-4 genotype I outbreak in 1990, was confirmed as DENV-4 genotype II and initially traced to the imported index case, a Guangzhou resident who travelled back from Thailand.

Sequence and recombination analyses of the geminivirus replication

Indian Academy of Sciences (India)

Prakash

2006-09-18

Sep 18, 2006 ... Recombination can provide selective advantage in the evolution of viruses .... Program (v 1.08): Recombination Detection Program (RDP). (Martin and Rybicki ..... Sweet potato leaf curl virus - [US:Louisiana:1994]. AF104036.

Chronic Active Epstein–Barr Virus Infection

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Li Jun

2012-06-01

Full Text Available Chronic active Epstein-Barr virus (CAEBV infection is a systemic Epstein-Barr virus (EBV positive lymphoprolifetative disease characterized by fever, lymphadenopathy, splenomegaly, unusual pattern of anti- EBV antibodies, and/or increased EBV genomes in affected tissues. Most cases are from Asia. So far, there is hardly any adult case reported from mainland of China. We herein presented a 33-year-old man with fever, facial erythema and rash, lymphadenopathy, lower limbs weakness, splenomegaly and liver lesion. EBV VCA, EA and EBNA were all positive. EBV DNA could be found in serum and PBMC. In situ hybridization of EBV encoded RNA in skin and liver biopsy was positive. Viral load in serum decreased under interferon alpha therapy. To our knowledge, it’s the first adult case reported from mainland of China.

Identification of equine influenza virus infection in Asian wild horses (Equus przewalskii).

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Yin, Xin; Lu, Gang; Guo, Wei; Qi, Ting; Ma, Jian; Zhu, Chao; Zhao, Shihua; Pan, Jialiang; Xiang, Wenhua

2014-05-01

An outbreak of equine influenza was observed in the Asian wild horse population in Xinjiang Province, China, in 2007. Nasal swabs were collected from wild horses and inoculated into 9-10-day SPF embryonated eggs. The complete genome of the isolate was sequenced. A comparison of the amino acid sequence revealed that the isolate was an equine influenza virus strain, which we named A/equine/Xinjiang/4/2007. Each gene of the virus was found to have greater than 99 % homology to equine influenza virus strains of the Florida-2 sublineage, which were circulating simultaneously in China, and a lesser amount of homology was found to the strain A/equine/Qinghai/1/1994 (European lineage), which was isolated during the last outbreak in China. These observations were confirmed by phylogenetic analysis. In addition, the deduced amino acid sequence of the neuraminidase of the A/equine/Xinjiang/4/2007 strain was identical to that of A/equine/California/8560/2002, an American isolate, and was found to be similar to those of Florida-2 strains found in other countries by comparing them with nine other field strains that were isolated in China from 2007 to 2008. It is suggested that the neuraminidase segment of A/equine/Xinjiang/4/2007 may have been obtained from equine influenza virus strains from other countries. We report for the first time an outbreak of equine influenza in the Asian wild horse population, and the complete genome of the virus is provided and analyzed.

Whole genome characterization of a novel porcine reproductive and respiratory syndrome virus 1 isolate: Genetic evidence for recombination between Amervac vaccine and circulating strains in mainland China.

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Chen, Nanhua; Liu, Qiaorong; Qiao, Mingming; Deng, Xiaoyu; Chen, Xizhao; Sun, Ming

2017-10-01

Genotype 1 porcine reproductive and respiratory syndrome virus (PRRSV 1) have been continuously isolated in China in recent years. Complete genome sequences of these isolates are important to investigate the prevalence and evolution of Chinese PRRSV 1. Herein, we describe the isolation of a novel PRRSV 1 isolate, denominated HLJB1, in the Heilongjiang province of China. Complete genome sequencing of HLJB1 showed that it shares 90.66% and 58.21% nucleotide identities with PRRSV 1 and 2 prototypic strains Lelystad virus and ATCC VR-2332, respectively. HLJB1 has a unique 5-amino-acid insertion in nsp2, which has never been described in other PRRSV 1 isolates. Whole genome-based phylogenetic analysis revealed that all Chinese PRRSV 1 isolates are clustered in pan-European subtype 1 and can be divided into four subgroups. HLJB1 resides in the subgroup of BJEU06-1-like isolates but is also closely related to the Amervac-like isolates. Additionally, recombination analyses suggested that HLJB1 is a recombinant from the Amervac vaccine and the BJEU06-1 isolate. To our best knowledge, our results provide the first genetic evidence for recombination between Amervac vaccine and circulating strains. These findings are also beneficial for studying the origin and evolution of PRRSV 1 in China. Copyright © 2017. Published by Elsevier B.V.

Isolation and Characterization of Encephalomyocarditis Virus from Dogs in China

NARCIS (Netherlands)

Luo, Ya-Kun; Liang, Lin; Tang, Qing-Hai; Zhou, Ling; Shi, Li-Jun; Cong, Ying-Ying; Lin, Wen-Cheng; Cui, Shang-Jin

2017-01-01

Encephalomyocarditis virus (EMCV) is as a potential zoonotic agent with a wide host range. Here, we describe an EMC virus isolate, identified as EMCV C15, which was successfully obtained from the serum of dogs from animal hospitals. Virus production in cell culture was confirmed by EMCV-specific

The Arabidopsis synaptotagmin SYTA regulates the cell-to-cell movement of diverse plant viruses

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Asako eUchiyama

2014-11-01

Full Text Available Synaptotagmins are a large gene family in animals that have been extensively characterized due to their role as calcium sensors to regulate synaptic vesicle exocytosis and endocytosis in neurons, and dense core vesicle exocytosis for hormone secretion from neuroendocrine cells. Thought to be exclusive to animals, synaptotagmins have recently been characterized in Arabidopsis thaliana, in which they comprise a five gene family. Using infectivity and leaf-based functional assays, we have shown that Arabidopsis SYTA regulates endocytosis and marks an endosomal vesicle recycling pathway to regulate movement protein-mediated trafficking of the Begomovirus Cabbage leaf curl virus (CaLCuV and the Tobamovirus Tobacco mosaic virus (TMV through plasmodesmata (Lewis and Lazarowitz, 2010. To determine whether SYTA has a central role in regulating the cell-to-cell trafficking of a wider range of diverse plant viruses, we extended our studies here to examine the role of SYTA in the cell-to-cell movement of additional plant viruses that employ different modes of movement, namely the Potyvirus Turnip mosaic virus (TuMV, the Caulimovirus Cauliflower mosaic virus (CaMV and the Tobamovirus Turnip vein clearing virus (TVCV, which in contrast to TMV does efficiently infect Arabidopsis. We found that both TuMV and TVCV systemic infection, and the cell-to-cell trafficking of the their movement proteins, were delayed in the Arabidopsis Col-0 syta-1 knockdown mutant. In contrast, CaMV systemic infection was not inhibited in syta-1. Our studies show that SYTA is a key regulator of plant virus intercellular movement, being necessary for the ability of diverse cell-to-cell movement proteins encoded by Begomoviruses (CaLCuV MP, Tobamoviruses (TVCV and TMV 30K protein and Potyviruses (TuMV P3N-PIPO to alter PD and thereby mediate virus cell-to-cell spread.

Acquired immunodeficiency syndrome/human immunodeficiency virus knowledge, attitudes, and practices, and use of healthcare services among rural migrants: a cross-sectional study in China

OpenAIRE

Wang, Ying; Cochran, Christopher; Xu, Peng; Shen, Jay J; Zeng, Gang; Xu, Yanjun; Sun, Mei; Li, Chengyue; Li, Xiaohong; Chang, Fengshui; Lu, Jun; Hao, Mo; Lu, Fan

2014-01-01

Background Today’s rapid growth of migrant populations has been a major contributor to the human immunodeficiency virus (HIV) epidemic. However, relatively few studies have focused on HIV/acquired immunodeficiency syndrome (AIDS)-related knowledge, attitudes, and practice among rural-to-urban migrants in China. This cross-sectional study was to assess HIV/AIDS-related knowledge and perceptions, including knowledge about reducing high-risk sex. Methods Two-phase stratified cluster sampling was...

Genetic, antigenic and pathogenic characterization of four infectious bursal disease virus isolates from China suggests continued evolution of very virulent viruses.

Science.gov (United States)

Li, Kai; Courtillon, Céline; Guionie, Olivier; Allée, Chantal; Amelot, Michel; Qi, Xiaole; Gao, Yulong; Wang, Xiaomei; Eterradossi, Nicolas

2015-03-01

Infectious bursal disease virus (IBDV) causes an economically significant disease of young chickens worldwide. The emergence of very virulent IBDV (vvIBDV) strains has brought more challenges for effective prevention and control of this disease. The aim of the present study was to characterize four IBDV isolates from various regions of China between late 1990s and recent years and to compare them with previously isolated European IBDV strains. In this study, one Chinese vvIBDV strain isolated in 1999 and three strains isolated between 2005 and 2011 were analyzed at the genetic, antigenic and pathogenic levels. Strain SH99 was closely related and clustered in the same genetic lineage as the typical vvIBDV based on the genomic sequences of segments A and B. However, the three more recent Chinese vvIBDV (HLJ0504, HeB10 and HuN11) showed several genetic changes in both segments and clustered in a distinct lineage from the typical vvIBDV and the previously known Chinese vvIBDV. Based on the binding to a panel of neutralizing monoclonal antibodies in antigen capture enzyme-linked immunosorbent assays, all Chinese vvIBDVs exhibited similar antigenicity with the European typical vvIBDV strains. Nonetheless, the pathogenicity caused by the recent Chinese vvIBDV was higher than that induced by the European typical vvIBDV. This study calls for a sustained surveillance of IBD situation in China in order to support a better prevention and control of the disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Migratory Whooper Swans Cygnus cygnus Transmit H5N1 Virus between China and Mongolia: Combination Evidence from Satellite Tracking and Phylogenetics Analysis.

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Li, Shuhong; Meng, Weiyue; Liu, Dongping; Yang, Qiqi; Chen, Lixia; Dai, Qiang; Ma, Tian; Gao, Ruyi; Ru, Wendong; Li, Yunfeng; Yu, Pengbo; Lu, Jun; Zhang, Guogang; Tian, Huaiyu; Chai, Hongliang; Li, Yanbing

2018-05-04

In late 2014, a highly pathogenic avian influenza (hereafter HPAI) H5N1 outbreak infected whooper swans Cygnus cygnus wintering at the Sanmenxia Reservoir area, China, and raised concerns about migratory linkages between wintering and breeding grounds of whooper swans. In this study, 61 swans were satellite tracked from 2013 to 2016 to determine the spatial association of their migration routes and H5N1 outbreaks, and 3596 fecal samples were collected along the migration routes for virology testing. Swans departed the wintering grounds and migrated along the Yellow River, and flew over the Yin Mountains in China. The Brownian bridge movement model showed there was a high degree of spatiotemporal overlap between the core use area along the spring migration pathway and historical H5N1 events in China and Mongolia from 2005 to 2015. The H5N1 strain was isolated and phylogenetic analyses confirmed that the HA gene sequence generated is genetically similar to that of the epidemic strain at a previous wintering site (the Sanmenxia Reservoir area) along its flyway. Our results identified a previously unknown migratory link of whooper swans in central China with Mongolia and confirmed that the swans could carry the HPAI H5N1 virus during migration, resulting in long-distance transmission.

Detection and Genetic Characterization of Lineage IV Peste Des Petits Ruminant Virus in Kazakhstan.

Science.gov (United States)

Kock, R A; Orynbayev, M B; Sultankulova, K T; Strochkov, V M; Omarova, Z D; Shalgynbayev, E K; Rametov, N M; Sansyzbay, A R; Parida, S

2015-10-01

Peste des petits ruminant (PPR) is endemic in many Asian countries with expansion of the range in recent years including across China during 2013-2014 (OIE, 2014). Till the end of 2014, no cases of PPR virus (PPRV) were officially reported to the Office Internationale des Epizooties (OIE) from Kazakhstan. This study describes for the first time clinicopathological, epidemiological and genetic characterization of PPRV in 3 farm level outbreaks reported for the first time in Zhambyl region (oblast), southern Kazakhstan. Phylogenetic analysis based on partial N gene sequence data confirms the lineage IV PPRV circulation, similar to the virus that recently circulated in China. The isolated viruses are 99.5-99.7% identical to the PPRV isolated in 2014 from Heilongjiang Province in China and therefore providing evidence of transboundary spread of PPRV. There is a risk of further maintenance of virus in young stock despite vaccination of adult sheep and goats, along livestock trade and pastoral routes, threatening both small livestock and endangered susceptible wildlife populations throughout Kazakhstan. © 2015 Blackwell Verlag GmbH.

[Stress, Needs, and Quality of Life of People Living With Human Immunodeficiency Virus/AIDS in North East China].

Science.gov (United States)

Tsai, Meng-Chu; Lu, Po-Liang; Wu, Shiau-Jiun; Feng, Ming-Chu

2017-04-01

HIV/AIDS has become a chronic disease since anti-retroviral therapy has reduced the related rates of morbidity and mortality and maintained the immunity of people living with the human immunodeficiency virus / AIDS (PLWHA). PLWHA have psychological needs and many hope to improve their quality of life (QoL) over the long course of their treatment. Despite the large number of AIDS cases, there are limited reports addressing the issue of QoL among PLWHA in China. The present study aims to explore the stress, needs, QoL, and related factors among PLWHA in China. This cross-sectional, descriptive study used a structural questionnaire to assess the stress, needs, and QoL of 100 PLWHA in Shenyang, China. The most stressful issues faced by the participants were admitting HIV/AIDS status publicly and explaining their illness to others. Their needs were mainly related to receiving adequate information about HIV-related medical services, examination, and treatment and learning how to prevent disease progression. Among the four domains of QoL, the score in the physical domain was the lowest. The stress, needs, and QoL of the participants were significantly inter-correlated. However, only stress was found to predict QoL (β = -.25 to -.60, p stress, meet the needs, and improve the QoL of PLWHA, healthcare providers should work to lower the risk of divulgence, provide adequate healthcare information, and work to reduce the stigma and discrimination that is associated with having HIV/AIDS.

[Zika Virus and Zika Viral Disease].

Science.gov (United States)

Zhang, Shuo; Li, Dexin

2016-01-01

Since Zika virus (ZIKV) has firstly been isolated in 1947, Uganda, outbreaks of Zika fever have been reported in many areas such as in Africa, Southeast Asia and America. Imported cases in China also have been reported. Zika virus belongs to the family Flaviviridae, genus Flavivirus, and include Africa subtype and Asia subtype. It is a mosquito-borne virus primarily transmitted by Aedes aegypti mosquitoes. Sexual transmission, Blood transmission and mother-to-fetus transmission were also reported. Zika virus can go though blood-brain barrier and infect central nervous system. Symptoms are generally mild and self-limited, but recent evidence suggests a possible association between maternal Zika virus infection and adverse fetal outcomes, such as congenital microcephaly, as well as a possible association with Guillain-Barré syndrome. Laboratorial Diagnosis includes nucleic acid detection, Serological test, and isolation of virus. Currently, no vaccine or medication exists to prevent or treat Zika virus infection. Preventive measures against Zika virus infection should be taken through prevention of mosquito bites and surveillance in epidemic area.

Simultaneous bilateral distal biceps tendon rupture during a preacher curl exercise: a case report.

Science.gov (United States)

Rokito, Andrew S; lofin, Ilya

2008-01-01

Complete rupture of the distal biceps tendon is a rare injury, the overwhelming majority occurring in the dominant arm of males during the fourth to sixth decades of life. Simultaneous bilateral rupture of the distal biceps tendon is an extremely rare occurrence, with only three cases reported in the literature. This unusual injury occurred in a recreational weightlifter during a preacher curl exercise. In this particular case, a 6-week delay in presentation necessitated a staged procedure in which a primary repair was feasible in one elbow, while reconstruction using allograft tissue was required in the contralateral elbow. Satisfactory results for both elbows were achieved, with return to weightlifting by one year following surgery.

Chinese and global distribution of H9 subtype avian influenza viruses.

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Wenming Jiang

Full Text Available H9 subtype avian influenza viruses (AIVs are of significance in poultry and public health, but epidemiological studies about the viruses are scarce. In this study, phylogenetic relationships of the viruses were analyzed based on 1233 previously reported sequences and 745 novel sequences of the viral hemagglutinin gene. The novel sequences were obtained through large-scale surveys conducted in 2008-2011 in China. The results revealed distinct distributions of H9 subtype AIVs in different hosts, sites and regions in China and in the world: (1 the dominant lineage of H9 subtype AIVs in China in recent years is lineage h9.4.2.5 represented by A/chicken/Guangxi/55/2005; (2 the newly emerging lineage h9.4.2.6, represented by A/chicken/Guangdong/FZH/2011, has also become prevalent in China; (3 lineages h9.3.3, h9.4.1 and h9.4.2, represented by A/duck/Hokkaido/26/99, A/quail/Hong Kong/G1/97 and A/chicken/Hong Kong/G9/97, respectively, have become globally dominant in recent years; (4 lineages h9.4.1 and h9.4.2 are likely of more risk to public health than others; (5 different lineages have different transmission features and host tropisms. This study also provided novel experimental data which indicated that the Leu-234 (H9 numbering motif in the viral hemagglutinin gene is an important but not unique determinant in receptor-binding preference. This report provides a detailed and updated panoramic view of the epidemiological distributions of H9 subtype AIVs globally and in China, and sheds new insights for the prevention of infection in poultry and preparedness for a potential pandemic caused by the viruses.

Thermal niches of two invasive genotypes of the wheat curl mite Aceria tosichella (Acari: Eriophyidae): congruence between physiological and geographical distribution data

Science.gov (United States)

The wheat curl mite (WCM; Aceria tosichella) is a major pest of cereals worldwide. It is also a complex of well-defined genetic lineages with divergent physiological traits, which has not been accounted for in applied contexts. The aims of the study were to model the thermal niches of the two most p...

[Experience of integrated traditional Chinese and Western medicine in first case of imported Zika virus disease in China].

Science.gov (United States)

Deng, Yichu; Zeng, Liping; Bao, Wen; Xu, Pinghua; Zhong, Gongrong

2016-02-01

Zika virus disease is an acute infectious disease caused by Zika virus transmitted through Aedes mosquitoes. To explore the therapeutic effect of integrated traditional Chinese and Western Medicine for Zika virus disease, the treatment process of the first imported case in China was reviewed. The first imported Zika virus disease in China was admitted to Ganxian People's Hospital in Jiangxi Province on February 6th, 2016, and the patient received isolation treatment for 9 days and cured later. The effect of antiviral treatments including Xiyanping injection was evaluated based on clinical diagnosis and treatment process of the patient. A 34-year old male patient was admitted with chief complaint of fever for 9 days, orbital pain and itching rash for 4 days on February 6th, 2016. (1) Epidemiological characteristics: the patient was bitted by mosquitoes during his business trip in Venezuela since January 1st, where Zika virus disease was spreading. On January 20th he had dizziness without fever, and the symptom disappeared after taking medicines without details. Paroxysmal dizziness, chills and mild fever without myalgia was experienced on January 28th. On February 3rd small red rash appeared in the neck, spreading to anterior part of chest, limbs and trunk, and the fever, fatigue, nausea was continued, and a new symptom of paroxysmal pain in back of ears and orbits appeared, during which he had not go to hospital. The symptoms relieved on February 4th. He returned to Ganxian County on February 5th, he had yellow stool 3 times with normal temperature, without abdominal pain, and red rash still appeared in the neck. He went to Ganxian People's Hospital on February 6th, 2016. (2) Clinical manifestation: the vital signs showed a temperature of 36.8?centigrade, a pulse rate of 80 bpm, a respiratory rate of 20 bpm, and a blood pressure of 110/70 mmHg (1 mmHg = 0.133 kPa). It was showed by physical examination that red rash appeared in the neck, and no superficial enlarged

Molecular characterization of a naturally occurring intraspecific recombinant begomovirus with close relatives widespread in southern Arabia

KAUST Repository

Al-Saleh, Mohammed A

2014-06-02

Background: Tomato leaf curl Sudan virus (ToLCSDV) is a single-stranded DNA begomovirus of tomato that causes downward leaf curl, yellowing, and stunting. Leaf curl disease results in significant yield reduction in tomato crops in the Nile Basin. ToLCSDV symptoms resemble those caused by Tomato yellow leaf curl virus, a distinct and widespread begomovirus originating in the Middle East. In this study, tomato samples exhibiting leaf curl symptoms were collected from Gezira, Sudan. The associated viral genome was molecularly characterized, analyzed phylogenetically, and an infectious clone for one isolate was constructed. Findings. The complete genomes for five newly discovered variants of ToLCSDV, ranging in size from 2765 to 2767-bp, were cloned and sequenced, and subjected to pairwise and phylogenetic analyses. Pairwise analysis indicated that the five Gezira isolates shared 97-100% nucleotide identity with each other. Further, these variants of ToLCSDV shared their highest nucleotide identity at 96-98%, 91-95%, 91-92%, and 91-92% with the Shambat, Gezira, Oman and Yemen strains of ToLCSDV, respectively. Based on the high maximum nucleotide identities shared between these ToLCSDV variants from Gezira and other previously recognized members of this taxonomic group, they are considered isolates of the Shambat strain of ToLCSDV. Analysis of the complete genome sequence for these new variants revealed that they were naturally occurring recombinants between two previously reported strains of ToLCSDV. Finally, a dimeric clone constructed from one representative ToLCSV genome from Gezira was shown to be infectious following inoculation to tomato and N. benthamiana plants. Conclusion: Five new, naturally occurring recombinant begomovirus variants (>96% shared nt identity) were identified in tomato plants from Gezira in Sudan, and shown to be isolates of the Shambat strain of ToLCSDV. The cloned viral genome was infectious in N. benthamiana and tomato plants, and symptoms

Energy efficiency guide for ice arenas and curling rinks

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

This document presented a set of guidelines which were designed to help operators of Manitoba's rinks and arenas by presenting practical ideas for saving money on energy in ice arenas, curling rinks, and similar recreational complexes. They cover a broad range of topics, from funding projects to details of specific components, and apply to new facilities, renovations, and day-to-day maintenance. These guidelines were based on a manual produced by the Saskatchewan Parks and Recreation Association in cooperation with the Saskatchewan Recreation Facility Association and sponsored by SaskPower. They represent an update of the 1991 manual to reflect improvements in technology, Manitoba Hydro's utility rates, and the requirements of Manitoba operators. The document presented guidelines and tips for understanding electrical and natural gas rates and structures; energy estimating methods; making a financial analysis; the building envelope; heating and ventilation; refrigeration; lighting; and heating effects of electrical equipment. Other guidelines presented came under the topics of operation and maintenance and project planning. Several appendices were also included, such as a glossary of terms; reference publications; energy calculations; power factor correction; heat pumps for rinks and arenas; and power smart programs for commercial buildings. refs., tabs., figs.

Suppressors of RNA silencing encoded by tomato leaf curl ...

Indian Academy of Sciences (India)

2013-01-06

Jan 6, 2013 ... Virus encoded RNA-silencing suppressors (RSSs) are the key components evolved by the viruses to ... severe disease symptom in the host (Briddon et al. ..... Voinnet O 2001 RNA silencing as a plant immune system against.

First report of a complete genome sequence for a begomovirus infecting Jatropha gossypifolia in the Americas.

Science.gov (United States)

Simmonds-Gordon, R N; Collins-Fairclough, A M; Stewart, C S; Roye, M E

2014-10-01

Jatropha gossypifolia is a weed that is commonly found with yellow mosaic symptoms growing along the roadside and in close proximity to cultivated crops in many farming communities in Jamaica. For the first time, the complete genome sequence of a new begomovirus, designated jatropha mosaic virus-[Jamaica:Spanish Town:2004] (JMV-[JM:ST:04]), was determined from field-infected J. gossypifolia in the western hemisphere. DNA-A nucleotide sequence comparisons showed closest identity (84 %) to two tobacco-infecting viruses from Cuba, tobacco mottle leaf curl virus-[Cuba:Sancti Spiritus:03] (TbMoLCV-[CU:SS:03]) and tobacco leaf curl Cuba virus-[Cuba:Taguasco:2005] (TbLCuCUV-[CU:Tag:05]), and two weed-infecting viruses from Cuba and Jamaica, Rhynchosia rugose golden mosaic virus-[Cuba:Camaguey:171:2009] (RhRGMV- [CU:Cam:171:09]) and Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). Phylogenetic analysis revealed that JMV-[JM:ST:04] is most closely related to tobacco and tomato viruses from Cuba and WGMSTV-[JM:Alb:05], a common malvaceous-weed-infecting virus from eastern Jamaica, and that it is distinct from begomoviruses infecting Jatropha species in India and Nigeria.

Is the pull-out force of the Meniscus Arrow in bone affected by the inward curling of the barbs during biodegradation? An in vitro study

NARCIS (Netherlands)

Wouters, Diederick B.; Burgerhof, Johannes G. M.; de Hosson, Jeff T. M.; Bos, Rudolf R. M.

Background: Inward curling of the barbs of Meniscus Arrows during degradation was observed in a previous study, in which swelling, distention, and water uptake by Meniscus Arrows was evaluated. This change of configuration could have consequences with respect to anchorage capacity in bone.

Penentuan Secara Imunopatologi Organ Target Virus Flu Burung Menggunakan Streptavidin Biotin (DETERMINATION OF TARGET ORGANS OF AVIAN INFLUENZA VIRUS USING IMMUNOPATHOLOGICAL IMMUNOHISTOCHEMISTRY STREPTAVIDIN-BIOTIN

Directory of Open Access Journals (Sweden)

Niken Yunita

2018-01-01

Full Text Available Avian influenza is a viral disease in poultry caused by avian influenza virus (AIV subtype H5N1 with varying clinical signs are often similar to the clinical signs of other viral infections, such as Newcastle disease virus (NDV. The mechanism of disease pathogenesis to express clinical signs tightly correlated to the determination of the target organ seen from AIV H5N1 antigens distribution in organs, such as respiratory tract, brain and gastrointestinal tract. Immunopathological immunohistochemistry streptavidin-biotin (IHC SB is a method for sensitive and accurate in detecting antigens of AIV on the tissues. In the present study, it was determined whether in laying hens with clinical signs of torticollis and curled toe paralysis, and pathologic anatomic lesions in the form of petechial and foci necrotic hemorrhages tested with immunopathological IHC SB is positive AIV H5N1 infection. IHC SB study results showed that the AIV H5N1 antigen were found in tissues of the lung, brain, duodenum and proventriculus. Based on these results, we can conclude that the IHC SB is a method that is highly sensitive and accurate to detect H5N1 antigens and its distribution in the host.

Genetic analysis of Asian measles virus strains--new endemic genotype in Nepal.

Science.gov (United States)

Truong, A T; Mulders, M N; Gautam, D C; Ammerlaan, W; de Swart, R L; King, C C; Osterhaus, A D; Muller, C P

2001-07-01

In many parts of Asia measles virus (MV) continues to be endemic. However, little is known about the genetic characteristics of viruses circulating on this continent. This study reports the molecular epidemiological analysis based on the entire nucleocapsid (N) and hemagglutinin (H) genes of the first isolates from Nepal and Taiwan, as well as of recent MV strains from India, Indonesia, and China. Four isolates collected in various regions in Nepal during 1999 belonged to a new genotype, tentatively called D8. Another Nepalese isolate and one from India belonged to genotype D4. The diversity of the Nepalese strains indicated that measles continues to be endemic in this country. The isolate from Taiwan grouped with D3 viruses and one Chinese strain isolated in The Netherlands was assigned to the previously described clade H, known to be endemic in Mainland China. Molecular characterization emerges as an important tool for monitoring virus endemicity and vaccination efforts.

Molucular Epidemiology and Evolution of Influenza Viruses Circulating within European Swine between 2009 and 2013

NARCIS (Netherlands)

Watson, S.J.; Langat, P.; Reid, S.; Lam, T.; Cotten, M.; Kelly, M.; Reeth, Van K.; Qiu, Y.; Simon, G.; Bonin, E.; Foni, E.; Chiapponi, C.; Larsen, L.; Hjulsager, C.; Markowska-Daniel, I.; Urbaniak, K.; Durrwald, R.; Schlegel, M.; Huovilainen, A.; Davidson, I.; Dan, A.; Loeffen, W.L.A.; Edwards, S.; Bublot, M.; Vila, T.; Maldonado, J.; Valls, L.; Brown, I.H.; Pybus, O.G.; Kellam, P.

2015-01-01

The emergence in humans of the A(H1N1)pdm09 influenza virus, a complex reassortant virus of swine origin, highlighted the importance of worldwide influenza virus surveillance in swine. To date, large-scale surveillance studies have been reported for southern China and North America, but such data

Rabies Outbreaks and Vaccination in Domestic Camels and Cattle in Northwest China.

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Ye Liu

2016-09-01

Full Text Available In contrast to many countries where rabies has been well controlled in humans and livestock, even in wildlife, rabies is still endemic in almost regions of China. In Northwest China, rabies transmitted by stray dogs and wild foxes has caused heavy economic losses to local herdsmen, as well as causing numbers of human cases. In this study, as part of an investigation of ways to prevent rabies epidemics in livestock, we report an analysis of domestic cattle and camel rabies cases in Ningxia Hui (NHAR and Inner Mongolia Autonomous Region (IMAR and the immune efficacy of canine inactivated rabies vaccines in these animals. We found that rabies viruses from these animals are closely related to dog-hosted China I and fox-associated China III lineages, respectively, indicating that the infections originated from two different sources (dogs and wild foxes. As well as the previously reported Arctic and Arctic-related China IV lineage in IMAR, at least three separate phylogenetic groups of rabies virus consistently exist and spread throughout Northwest China. Since there is no licensed oral vaccine for wild foxes and no inactivated vaccine for large livestock, local canine inactivated vaccine products were used for emergency immunization of beef and milk cattle and bactrian (two-humped camels in local farms. Compared with a single injection with one (low-efficacy or three doses (high-cost, a single injection of a double dose of canine vaccine provided low-price and convenience for local veterinarians while inducing levels of virus neutralizing antibodies indicative of protection against rabies for at least 1 year in the cattle and camels. However, licensed vaccines for wildlife and large domestic animals are still needed in China.

Development, Production, and Postmarketing Surveillance of Hepatitis A Vaccines in China

Science.gov (United States)

Cui, Fuqiang; Liang, Xiaofeng; Wang, Fuzhen; Zheng, Hui; Hutin, Yvan J; Yang, Weizhong

2014-01-01

China has long experience using live attenuated and inactivated vaccines against hepatitis A virus (HAV) infection. We summarize this experience and provide recent data on adverse events after immunization (AEFIs) with hepatitis A vaccines in China. We reviewed the published literature (in Chinese and English) and the published Chinese regulatory documents on hepatitis A vaccine development, production, and postmarketing surveillance of AEFI. We described the safety, immunogenicity, and efficacy of hepatitis A vaccines and horizontal transmission of live HAV vaccine in China. In clinical trials, live HAV vaccine was associated with fever (0.4%–5% of vaccinees), rash (0%–1.1%), and elevated alanine aminotransferase (0.015%). Inactivated HAV vaccine was associated with fever (1%–8%), but no serious AEFIs were reported. Live HAV vaccine had seroconversion rates of 83% to 91%, while inactivated HAV vaccine had seroconversion rates of 95% to 100%. Community trials showed efficacy rates of 90% to 95% for live HAV and 95% to 100% for inactivated HAV vaccine. Postmarketing surveillance showed that HAV vaccination resulted in an AEFI incidence rate of 34 per million vaccinees, which accounted for 0.7% of adverse events reported to the China AEFI monitoring system. There was no difference in AEFI rates between live and inactivated HAV vaccines. Live and inactivated HAV vaccines manufactured in China were immunogenic, effective, and safe. Live HAV vaccine had substantial horizontal transmission due to vaccine virus shedding; thus, further monitoring of the safety of virus shedding is warranted. PMID:24681843

Duck egg-drop syndrome caused by BYD virus, a new Tembusu-related flavivirus.

Directory of Open Access Journals (Sweden)

Jingliang Su

Full Text Available Since April 2010, a severe outbreak of duck viral infection, with egg drop, feed uptake decline and ovary-oviduct disease, has spread around the major duck-producing regions in China. A new virus, named BYD virus, was isolated in different areas, and a similar disease was reproduced in healthy egg-producing ducks, infecting with the isolated virus. The virus was re-isolated from the affected ducks and replicated well in primary duck embryo fibroblasts and Vero cells, causing the cytopathic effect. The virus was identified as an enveloped positive-stranded RNA virus with a size of approximately 55 nm in diameter. Genomic sequencing of the isolated virus revealed that it is closely related to Tembusu virus (a mosquito-borne Ntaya group flavivirus, with 87-91% nucleotide identity of the partial E (envelope proteins to that of Tembusu virus and 72% of the entire genome coding sequence with Bagaza virus, the most closely related flavivirus with an entirely sequenced genome. Collectively our systematic studies fulfill Koch's postulates, and therefore, the causative agent of the duck egg drop syndrome occurring in China is a new flavivirus. Flavivirus is an emerging and re-emerging zoonotic pathogen and BYD virus that causes severe egg-drop, could be disastrous for the duck industry. More importantly its public health concerns should also be evaluated, and its epidemiology should be closely watched due to the zoonotic nature of flaviviruses.

Molecular detection and sequence characterization of diverse rhabdoviruses in bats, China.

Science.gov (United States)

Xu, Lin; Wu, Jianmin; Jiang, Tinglei; Qin, Shaomin; Xia, Lele; Li, Xingyu; He, Biao; Tu, Changchun

2018-01-15

The Rhabdoviridae is among the most diverse families of RNA viruses and currently classified into 18 genera with some rhabdoviruses lethal to humans and other animals. Herein, we describe genetic characterization of three novel rhabdoviruses from bats in China. Of these, two viruses (Jinghong bat virus and Benxi bat virus) found in Rhinolophus bats showed a phylogenetic relationship with vesiculoviruses, and sequence analyses indicate that they represent two new species within the genus Vesiculovirus. The remaining Yangjiang bat virus found in Hipposideros larvatus bats were only distantly related to currently known rhabdoviruses. Copyright © 2017 Elsevier B.V. All rights reserved.

A population-based study examining hepatitis B virus infection and immunization rates in Northwest China.

Directory of Open Access Journals (Sweden)

Zhaohua Ji

Full Text Available BACKGROUND AND AIM: Current baseline data regarding the prevalence of hepatitis B virus (HBV infections and the immune status in hyperendemic areas is necessary in evaluating the effectiveness of ongoing HBV prevention and control programs in northwest China. This study aims to determine the prevalence of chronic HBV infections, past exposure rates, and immune response profiles in Wuwei City, northwest China in 2010. METHODS: Cross-sectional household survey representative of the Wuwei City population. 28,579 participants were interviewed in the seroepidemiological survey ≥1 year of age. House to house screening was conducted using a standard questionnaire. All serum samples were screened by enzyme-linked immunoassays for the presence of hepatitis B surface antigen, antibodies against HBV surface antigen, and antibodies to the hepatitis B core antigen. RESULTS: Among individuals ≥1 year of age, 7.2% (95%CI: 6.3-8.1% had chronic HBV infections, 43.9% (CI: 40.4-47.4% had been exposed to HBV, and 23.49% (CI: 21.6-25.3% had vaccine-induced immunity. Multi-factor weighted logistic regression analysis showed that having household contact with HBV carriers (OR = 2.6, 95%CI: 2.3-3.0 and beauty treatments in public places (OR = 1.2, 95%CI: 1.1-1.3 were the risk factors of HBV infection in whole population. Having household contact with HBV carriers (OR = 3.8, 95% CI: 2.2-6.5 and lack of hepatitis vaccination (OR = 2.0, 95% CI: 1.4-3.3 were the risk factors for HBV infection in children aged 1-14 years. CONCLUSIONS: Hepatitis B infection remains a serious public health problem in northwest China. Having household contact with HBV carriers and beauty treatments in public places represented HBV infection risk factors. Hepatitis B vaccine immunization strategies need further improvement, particularly by targeting the immunization of rural migrant workers.

Predicting Hotspots for Influenza Virus Reassortment

Science.gov (United States)

Gilbert, Marius; Martin, Vincent; Cappelle, Julien; Hosseini, Parviez; Njabo, Kevin Y.; Abdel Aziz, Soad; Xiao, Xiangming; Daszak, Peter; Smith, Thomas B.

2013-01-01

The 1957 and 1968 influenza pandemics, each of which killed ≈1 million persons, arose through reassortment events. Influenza virus in humans and domestic animals could reassort and cause another pandemic. To identify geographic areas where agricultural production systems are conducive to reassortment, we fitted multivariate regression models to surveillance data on influenza A virus subtype H5N1 among poultry in China and Egypt and subtype H3N2 among humans. We then applied the models across Asia and Egypt to predict where subtype H3N2 from humans and subtype H5N1 from birds overlap; this overlap serves as a proxy for co-infection and in vivo reassortment. For Asia, we refined the prioritization by identifying areas that also have high swine density. Potential geographic foci of reassortment include the northern plains of India, coastal and central provinces of China, the western Korean Peninsula and southwestern Japan in Asia, and the Nile Delta in Egypt. PMID:23628436

Pigsties near dwellings as a potential risk factor for the prevalence of Japanese encephalitis virus in adult in Shanxi, China.

Science.gov (United States)

Ren, Xiaojie; Fu, Shihong; Dai, Peifang; Wang, Huanyu; Li, Yuanyuan; Li, Xiaolong; Lei, Wenwen; Gao, Xiaoyan; He, Ying; Lv, Zhi; Cheng, Jingxia; Wang, Guiqin; Liang, Guodong

2017-06-08

The increasing trend of adult cases of Japanese encephalitis (JE) in China, particularly in northern China, has become an important public health issue. We conducted an epidemiological investigation in the south of Shanxi Province to examine the relationships between mosquitoes, Japanese encephalitis virus (JEV), and adult JE cases. Mosquito specimens were collected from the courtyards of farmers' households and pig farms in Shanxi Province. Mosquitoes were pooled, homogenized, and centrifuged. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mosquito-borne arbovirus genes in homogenates. Specimens positive for these genes were inoculated into the baby hamster kidney cell line (BHK-21) to isolate virus. Minimum infection rate was calculated and phylogenetic analyses were performed. A total of 7 943 mosquitoes belonging to six species in four genera were collected; Culex tritaeniorhynchus accounted for 73.08% (5 805/7 943), C. pipiens pallens for 24.75% (1 966/7 943), and the remaining 3% (104/ 7943) consisted of Anopheles sinensis, Aedes vexans, Ae. dorsalis, and Armigeres subalbatus. Sixteen pools were positive for JEV based on RT-PCR using JEV pre-membrane gene nested primers. Phylogenetic analyses showed that all JEVs belonged to genotype I; two pools were positive using Getah Virus (GETV) gene primers. In addition, one JEV strain (SXYC1523) was isolated from C. pipiens pallens specimens. These results indicate that the minimum infection rate of JEV in mosquito specimens collected from the courtyards of farmers' households with pigsties was 7.39/1 000; the rate for pig farms was 2.68/1 000; and the rate for farmers' courtyards without pigsties was zero. The high-prevalence regions of adult JE investigated in this study are still the natural epidemic focus of JEV. Having pigsties near dwellings is a potential risk factor contributing to the prevalence of adult JE. To prevent the occurrence of local adult JE cases, a recommendation was

Simple and Accurate Analytical Solutions of the Electrostatically Actuated Curled Beam Problem

KAUST Repository

Younis, Mohammad I.

2014-08-17

We present analytical solutions of the electrostatically actuated initially deformed cantilever beam problem. We use a continuous Euler-Bernoulli beam model combined with a single-mode Galerkin approximation. We derive simple analytical expressions for two commonly observed deformed beams configurations: the curled and tilted configurations. The derived analytical formulas are validated by comparing their results to experimental data in the literature and numerical results of a multi-mode reduced order model. The derived expressions do not involve any complicated integrals or complex terms and can be conveniently used by designers for quick, yet accurate, estimations. The formulas are found to yield accurate results for most commonly encountered microbeams of initial tip deflections of few microns. For largely deformed beams, we found that these formulas yield less accurate results due to the limitations of the single-mode approximations they are based on. In such cases, multi-mode reduced order models need to be utilized.

Silicified virus-like nanoparticles in an extreme thermal environment: implications for the preservation of viruses in the geological record.

Science.gov (United States)

Peng, X; Xu, H; Jones, B; Chen, S; Zhou, H

2013-11-01

Biofilms that grow around Gumingquan hot spring (T = 71 °C, pH = 9.2) in the Rehai geothermal area, Tengchong, China, are formed of various cyanobacteria, Firmicutes, Aquificae, Thermodesulfobacteria, Desulfurococcales, and Thermoproteales. Silicified virus-like nanoparticles, 40-200 nm in diameter, are common inside the microbial cells and the extracellular polymeric substances around the cells. These nanoparticles, which are formed of a core encased by a silica cortex, are morphologically akin to known viruses and directly comparable to silicified virus-like particles that were produced in biofilms cultured in the laboratory. The information obtained from examination of the natural and laboratory-produced samples suggests that viruses can be preserved by silicification, especially while they are still encased in their host cells. These results expand our views of virus-host mineral interaction in extreme thermal environments and imply that viruses can be potentially preserved and identified in the geological record. © 2013 John Wiley & Sons Ltd.

HIV-1 CRF_BC recombinants infection in China: molecular epidemic and characterizations.

Science.gov (United States)

Ouyang, Yabo; Shao, Yiming; Ma, Liying

2012-03-01

CRF_BC recombinant strains were first identified in China and are one of the most prevalent and characteristically unique HIV-1 subtypes across China. Here we aim to review the published data about HIV-1 CRF_BC recombinant strains epidemic in China and to characterize the genetics, biology and drug resistance of this virus. This study may help to better understand the current situation of HIV-1 CRF_BC prevalence and facilitate the development of vaccines and more efficient anti-HIV-1 regimens in China.

Application of Failure Mode and Effect Analysis (FMEA), cause and effect analysis, and Pareto diagram in conjunction with HACCP to a corn curl manufacturing plant.

Science.gov (United States)

Varzakas, Theodoros H; Arvanitoyannis, Ioannis S

2007-01-01

The Failure Mode and Effect Analysis (FMEA) model has been applied for the risk assessment of corn curl manufacturing. A tentative approach of FMEA application to the snacks industry was attempted in an effort to exclude the presence of GMOs in the final product. This is of crucial importance both from the ethics and the legislation (Regulations EC 1829/2003; EC 1830/2003; Directive EC 18/2001) point of view. The Preliminary Hazard Analysis and the Fault Tree Analysis were used to analyze and predict the occurring failure modes in a food chain system (corn curls processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram, and the fishbone diagram). Finally, Pareto diagrams were employed towards the optimization of GMOs detection potential of FMEA.

Hemorrhagic Fever Caused by a Novel Bunyavirus in China: Pathogenesis and Correlates of Fatal Outcome

NARCIS (Netherlands)

Zhang, Yong-Zhen; He, Yong-Wen; Dai, Yong-An; Xiong, Yanwen; Zheng, Han; Zhou, Dun-Jin; Li, Juan; Sun, Qiangzheng; Luo, Xue-Lian; Cheng, Yu-Li; Qin, Xin-Cheng; Tian, Jun-Hua; Chen, Xiao-Ping; Yu, Bin; Jin, Dong; Guo, Wen-Ping; Li, Wei; Wang, Wen; Peng, Jin-Song; Zhang, Guo-Bin; Zhang, Shaomin; Chen, Xiao-Min; Wang, Yan; Li, Ming-Hui; Li, Zhenjun; Lu, Shan; Ye, Changyun; de Jong, Menno D.; Xu, Jianguo

2012-01-01

Background. Hemorrhagic fever-like illness caused by a novel Bunyavirus, Huaiyangshan virus (HYSV, also known as Severe Fever with Thrombocytopenia virus [SFTSV] and Fever, Thrombocytopenia and Leukopenia Syndrome [FTLS]), has recently been described in China. Methods. Patients with

Insecticides promote viral outbreaks by altering herbivore competition.

Science.gov (United States)

Pan, Huipeng; Preisser, Evan L; Chu, Dong; Wang, Shaoli; Wu, Qingjun; Carriére, Yves; Zhou, Xuguo; Zhang, Youjun

2015-09-01

While the management of biological invasions is often characterized by a series of single-specieg decisions, invasive species exist within larger food webs. These biotic interactions can alter the impact of control/eradication programs and may cause suppression efforts to inadvertently facilitate invasion spread and impact. We document the rapid replacement of the invasive Bemisia Middle East-Asia Minor I (MEAM1) cryptic biotype by the cryptic Mediterranean (MED) biotype throughout China and demonstrate that MED is more tolerant of insecticides and a better vector of tomato yellow leaf curl virus (TYLCV) than MEAMJ. While MEAM1 usually excludes MED under natural conditions, insecticide application reverses the MEAM1-MED competitive hierarchy and allows MED to exclude MEAMI. The insecticide-mediated success of MED has led to TYLCV outbreaks throughout China. Our work strongly supports the hypothesis that insecticide use in China reverses the MEAMl-MED competitive hierarchy and allows MED to displace MEAM1 in managed landscapes. By promoting the dominance of a Bemisia species that is a competent viral vector, insecticides thus increase the spread and impact of TYLCV in heterogeneous agroecosystems.

Functional analysis of bipartite begomovirus coat protein promoter sequences

International Nuclear Information System (INIS)

Lacatus, Gabriela; Sunter, Garry

2008-01-01

We demonstrate that the AL2 gene of Cabbage leaf curl virus (CaLCuV) activates the CP promoter in mesophyll and acts to derepress the promoter in vascular tissue, similar to that observed for Tomato golden mosaic virus (TGMV). Binding studies indicate that sequences mediating repression and activation of the TGMV and CaLCuV CP promoter specifically bind different nuclear factors common to Nicotiana benthamiana, spinach and tomato. However, chromatin immunoprecipitation demonstrates that TGMV AL2 can interact with both sequences independently. Binding of nuclear protein(s) from different crop species to viral sequences conserved in both bipartite and monopartite begomoviruses, including TGMV, CaLCuV, Pepper golden mosaic virus and Tomato yellow leaf curl virus suggests that bipartite begomoviruses bind common host factors to regulate the CP promoter. This is consistent with a model in which AL2 interacts with different components of the cellular transcription machinery that bind viral sequences important for repression and activation of begomovirus CP promoters

Monitoring potential geographical distribution of four wild bird species in China

Science.gov (United States)

Dai, S.; Feng, D.; Xu, B.

2015-12-01

The outbreak of highly pathogenic avian influenza (HPAI) of the H5N1 subtype in wild birds and poultry have caught worldwide attention. To explore the association between wild bird migration and avian influenza virus transmission, we monitored potential geographical distribution of four wild bird species that might carry the avian influenza viruses in China. They are Bar-headed geese (Anser indicus), Ruddy Shelduck (Tadorna ferruginea), Whooper Swan (Cygnus cygnus) and Black-headed Gull (Larus ridibundus). They served as major reservoir of the avian influenza viruses. We used bird watching records with the precise latitude/longitude coordinates from January 2002 to August 2014, and environmental variables with a pixel resolution of 5 km × 5 km from 2002 to 2014. The study utilized maximum entropy (MaxEnt) model based on ecological niche model approaches, and got the following results: 1) MaxEnt model have good discriminatory ability with the area under the curve (AUC) of the receiver operating curve (ROC) of 0.86-0.97; 2) The four wild bird species were estimated to concentrate in the North China Plain, the middle and lower region of the Yangtze River, Qinghai Lake, Tianshan Mountain and Tarim Basin, part of Tibet Plateau, and Hengduan Mountains; 3) Radiation and the minimum temperature were found to provide the most significant information. Our findings will help to understand the spread of avian influenza viruses by wild bird migration in China, which benefits for effective monitoring strategies and prevention measures.

Serological evidence of ebolavirus infection in bats, China

Directory of Open Access Journals (Sweden)

Yuan Junfa

2012-10-01

Full Text Available Abstract Background The genus Ebolavirus of the family Filoviridae currently consists of five species. All species, with the exception of Reston ebolavirus, have been found in Africa and caused severe human diseases. Bats have been implicated as reservoirs for ebolavirus. Reston ebolavirus, discovered in the Philippines, is the only ebolavirus species identified in Asia to date. Whether this virus is prevalent in China is unknown. Findings In this study, we developed an enzyme linked immunosorbent assay (ELISA for ebolavirus using the recombinant nucleocapsid protein and performed sero-surveillance for the virus among Chinese bat populations. Our results revealed the presence of antibodies to ebolavirus in 32 of 843 bat sera samples and 10 of 16 were further confirmed by western blot analysis. Conclusion To our knowledge, this is the first report of any filovirus infection in China.

Emergence of canine distemper virus strains with two amino acid substitutions in the haemagglutinin protein, detected from vaccinated carnivores in North-Eastern China in 2012-2013.

Science.gov (United States)

Zhao, Jianjun; Zhang, Hailing; Bai, Xue; Martella, Vito; Hu, Bo; Sun, Yangang; Zhu, Chunsheng; Zhang, Lei; Liu, Hao; Xu, Shujuan; Shao, Xiqun; Wu, Wei; Yan, Xijun

2014-04-01

A total of 16 strains of canine distemper virus (CDV) were detected from vaccinated minks, foxes, and raccoon dogs in four provinces in North-Eastern China between the end of 2011 and 2013. Upon sequence analysis of the haemagglutinin gene and comparison with wild-type CDV from different species in the same geographical areas, two non-synonymous single nucleotide polymorphisms were identified in 10 CDV strains, which led to amino acid changes at positions 542 (isoleucine to asparagine) and 549 (tyrosine to histidine) of the haemagglutinin protein coding sequence. The change at residue 542 generated a potentially novel N-glycosylation site. Masking of antigenic epitopes by sugar moieties might represent a mechanism for evasion of virus neutralising antibodies and reduced protection by vaccination. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fighting against infectious diseases in China.

Science.gov (United States)

Yin, Weidong

2011-12-01

Dr. Yin started his research on infectious disease prevention in the 1980s. In 1985, Dr. Yin sucessfully isolated the hepatitis A virus, after which, in 2002, he developed the first proprietary inactivated hepatitis A vaccine in China and soon launched it into the China market. Led by Dr. Yin, Sinovac successfully developed the vaccine prducts against SARS, H5N1, H1N1, hepatitis A and B and infleunza. Currently, Sinovac is working on the R&D of EV71 vaccine against hand, foot and mouth disease, and pneumococcal conjugate vaccine. Sinovac aims to provide Chinese children with international quality vaccines, and provide children in the world with vaccines made in China.

General epidemiological parameters of viral hepatitis A, B, C, and E in six regions of China: a cross-sectional study in 2007.

Science.gov (United States)

Lu, Jian; Zhou, Yongdong; Lin, Xiaojing; Jiang, Yongzhen; Tian, Ruiguang; Zhang, Yonghui; Wu, Jia; Zhang, Fengwei; Zhang, Yong; Wang, Yue; Bi, Shengli

2009-12-24

Viral hepatitis is a serious health burden worldwide. To date, few reports have addressed the prevalence of hepatitis A, B, C, and E in China. Therefore, the general epidemiological parameters of viral hepatitis remain unknown. In this cross-sectional study, we performed a serological prevalence analysis of viral hepatitis A, B, C, and E in 8,762 randomly selected Chinese subjects, which represented six areas of China. The overall prevalence of anti-Hepatitis C virus antibody (anti-HCV) was 0.58%, which was much lower than was estimated by WHO. The prevalences of Hepatitis B virus surface antigen (HBsAg), anti-Hepatitis B virus surface protein antibody (HBsAb), and anti-Hepatitis B virus core protein antibody (HBcAb) were 5.84%, 41.31%, and 35.92%, respectively, whereas in the group of subjects less than 5 years old, these prevalences were 1.16%, 46.77%, and 8.69% respectively, which suggests that the Hepatitis B virus (HBV)-carrier population is decreasing, and the nationwide HBV vaccine program has contributed to the lowered HBV prevalence in the younger generation in China. Meanwhile, a large deficit remains in coverage provided by the national HBV immune program. In addition, our data suggested the possibility that HBsAb may not last long enough to protect people from HBV infection throughout life. The overall prevalence of anti-Hepatitis A virus antibody (anti-HAV) and anti-Hepatitis E virus antibody (anti-HEV) were as high as 72.87% and 17.66%, respectively. The indices increased with age, which suggests that a large proportion of Chinese adults are protected by latent infection. Furthermore, the pattern of HEV infection was significantly different among ethnic groups in China. Our study provided much important information concerning hepatitis A, B, C, and E prevalence in China and will contribute to worldwide oversight of viral hepatitis.

High hepatitis E virus antibody positive rates in dogs and humans exposed to dogs in the south-west of China.

Science.gov (United States)

Zeng, M Y; Gao, H; Yan, X X; Qu, W J; Sun, Y K; Fu, G W; Yan, Y L

2017-12-01

Hepatitis E (HE) is a zoonotic viral disease caused by hepatitis E virus (HEV). The objective of this study was to investigate the prevalence of HEV infection among dogs and humans exposed to dogs in the south-west region of China. A total of 4,490 dog serum samples and 2,206 relative practitioner serum samples were collected from 18 pet hospitals and dog farms in Yunnan, Sichuan and Guizhou province, and the anti-HEV IgG antibodies were detected by ELISA. The results showed that the total positive rate of anti-HEV antibodies was 36.55% with the highest rate in city stray dogs, and the differences in distinct species and growth phases were significant. The positive rate of anti-HEV antibody in veterinarian and farm staff-related practitioners was significantly higher than the general population. The finding of the present survey suggested that high HEV seroprevalence in dogs and humans exposed to dogs in the south-west area of China poses a significant public health concern. It is urgent to improve integrated strategies to detect, prevent and control HEV infection in dogs and humans exposed to dogs in this area. © 2017 Blackwell Verlag GmbH.

Prevalence and Determinants of Herpes Simplex Virus Type 2 (HSV-2)/Syphilis Co-Infection and HSV-2 Mono-Infection among Human Immunodeficiency Virus Positive Men Who Have Sex with Men: a Cross-Sectional Study in Northeast China.

Science.gov (United States)

Hu, Qing-Hai; Xu, Jun-Jie; Chu, Zhen-Xing; Zhang, Jing; Yu, Yan-Qiu; Yu, Huan; Ding, Hai-Bo; Jiang, Yong-Jun; Geng, Wen-Qing; Wang, Ning; Shang, Hong

2017-05-24

This study assessed the prevalence and determinants of herpes simplex virus type 2 (HSV-2)/syphilis co-infection and HSV-2 mono-infection in human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) in China. A cross-sectional study was conducted of 545 HIV-positive MSM in Shenyang between February 2009 and October 2014. Participants underwent physical examinations and serological tests for HSV-2 and syphilis. A multinomial logistic regression was used to identify the risk factors associated with HSV-2/syphilis co-infection and HSV-2 mono-infection. The prevalence of HSV-2 mono-infection, syphilis mono-infection, and HSV-2/syphilis co-infection (95% confidence interval) was 48.6% (44.4-52.8%), 34.3% (30.3-38.3%), and 22.9% (19.4-26.5%), respectively. After controlling within HSV-2/syphilis-seropositive cases, regression analysis revealed that the related factors for HSV-2/syphilis co-infection included age (25-50 vs. ≤ 24 years: adjusted odds ratio [aOR], 4.55; > 50 vs. ≤ 24 years: aOR, 43.02), having regular female sexual partner(s) in the past 6 months (aOR, 0.43), and age at first MSM experience (≤ 18 vs. > 18 years: aOR, 2.59) (all P syphilis co-infection in HIV-positive MSM indicates a high secondary HIV transmission risk. A campaign for detection and treatment of HSV-2 and syphilis is urgently required for HIV-positive MSM in China.

An AFLP marker linked to turnip mosaic virus resistance gene in pak ...

African Journals Online (AJOL)

An AFLP marker linked to turnip mosaic virus resistance gene in pak-choi. W Xinhua, C Huoying, Z Yuying, H Ruixian. Abstract. Pak-choi is one of the most important vegetable crops in China. Turnip mosaic virus (TuMV) is one of its main pathogen. Screening the molecular marker linked to the TuMV resistance gene is an ...

Survey of the first case of Zika virus disease in the mainland of China%中国大陆首例输入性寨卡病毒病病例调查分析

Institute of Scientific and Technical Information of China (English)

廖勇; 曾志笠; 胡国良; 杨健平; 袁辉; 李建华; 张兴茂; 黄仁发; 刘晓青

2016-01-01

Objective To analyze epidemiological characteristics of the first laboratory confirmed case of Zika virus disease in the mainland China,and provide evidence for the prevention and control of the spread of Zika virus disease.Methods Epidemiological survey was conducted for the first suspect case of Zika virus disease in China,and medical observation was conducted for the close contacts.The nucleic acid detection of Zika virus was conducted with Real-time RT-PCR by using blood and urine samples collected from the cases.Results The ftrst case of Zika virus disease was confirmed.The case was cured and discharged on 18th day after the onset.The blood sample on 10th day after the onset and urine samples on 11-13th days after the onset were all positive for Zika virus.The case had the history of mosquito bites in the endemic country before the onset.The close contacts showed no Zika virus disease-like symptoms during the medical observation period.Conclusion The case reported by Jiangxi province was the first imported case of Zika virus disease in the mainland of China.The infection was related with the mosquito bites in Venezuela where Zika virus disease in endemic.%目的 分析2016年2月9日中国大陆首例确诊寨卡病毒病病例的流行病学特征,为防控寨卡病毒病提供参考依据.方法 对中国大陆首例确诊寨卡病毒病病例进行流行病学调查并临床观察病例同行者与接触者.采集病例血清、尿液等标本,应用荧光定量RT-PCR进行核酸检测.结果 该病例确诊为寨卡病毒病,于第18病日解除隔离、痊愈出院.病例第10病日血清标本和第11～ 13病日尿液标本检测均为寨卡病毒核酸阳性.该病例系江西省赣县籍外派工作回国人员,发病前在寨卡病毒流行地区有蚊虫叮咬史,同行者与接触者医学观察期内均未出现寨卡病毒病症状.结论 该病例为中国大陆首例寨卡病毒感染确诊病例,系境外输入性病例,感染来源与在寨卡疫源地委内瑞拉蚊虫叮咬有关.

Genome-wide analysis of Epstein-Barr virus identifies variants and genes associated with gastric carcinoma and population structure.

Science.gov (United States)

Yao, Youyuan; Xu, Miao; Liang, Liming; Zhang, Haojiong; Xu, Ruihua; Feng, Qisheng; Feng, Lin; Luo, Bing; Zeng, Yi-Xin

2017-10-01

Epstein-Barr virus is a ubiquitous virus and is associated with several human malignances, including the significant subset of gastric carcinoma, Epstein-Barr virus-associated gastric carcinoma. Some Epstein-Barr virus-associated diseases are uniquely prevalent in populations with different geographic origins. However, the features of the disease and geographically associated Epstein-Barr virus genetic variation as well as the roles that the variation plays in carcinogenesis and evolution remain unclear. Therefore, in this study, we sequenced 95 geographically distinct Epstein-Barr virus isolates from Epstein-Barr virus-associated gastric carcinoma biopsies and saliva of healthy donors to detect variants and genes associated with gastric carcinoma and population structure from a genome-wide spectrum. We demonstrated that Epstein-Barr virus revealed the population structure between North China and South China. In addition, we observed population stratification between Epstein-Barr virus strains from gastric carcinoma and healthy controls, indicating that certain Epstein-Barr virus subtypes are associated with different gastric carcinoma risks. We identified that the BRLF1, BBRF3, and BBLF2/BBLF3 genes had significant associations with gastric carcinoma. LMP1 and BNLF2a genes were strongly geographically associated genes in Epstein-Barr virus. Our study provides insights into the genetic basis of oncogenic Epstein-Barr virus for gastric carcinoma, and the genetic variants associated with gastric carcinoma can serve as biomarkers for oncogenic Epstein-Barr virus.

Como diferenciar uma marca num mercado pouco heterogéneo: inovação da Rip Curl

OpenAIRE

Real, Isabel Corte

2011-01-01

Mestrado em Marketing A partir de uma paixão pessoal que é o surf, e um interesse cada vez maior pelas novas tecnologias e como elas estão a mudar tudo à nossa volta, surgiu a ideia de criar um projecto para uma marca de surf que tem investido muito em Portugal, percebendo o potencial que o nosso país tem com tantos quilómetros de costa. As conclusões retiradas do quadro teórico e de toda a envolvente externa e interna à Rip Curl permitem apresentar um plano inovador para a criação de u...

High-order Div- and Quasi Curl-Conforming Basis Functions for Calderón Multiplicative Preconditioning of the EFIE

KAUST Repository

Valdes, Felipe; Andriulli, Francesco P.; Cools, Kristof; Michielssen, Eric

2011-01-01

A new high-order Calderón multiplicative preconditioner (HO-CMP) for the electric field integral equation (EFIE) is presented. In contrast to previous CMPs, the proposed preconditioner allows for high-order surface representations and current expansions by using a novel set of high-order quasi curl-conforming basis functions. Like its predecessors, the HO-CMP can be seamlessly integrated into existing EFIE codes. Numerical results demonstrate that the linear systems of equations obtained using the proposed HO-CMP converge rapidly, regardless of the mesh density and of the order of the current expansion. © 2006 IEEE.

High-order Div- and Quasi Curl-Conforming Basis Functions for Calderón Multiplicative Preconditioning of the EFIE

KAUST Repository

Valdes, Felipe

2011-04-01

A new high-order Calderón multiplicative preconditioner (HO-CMP) for the electric field integral equation (EFIE) is presented. In contrast to previous CMPs, the proposed preconditioner allows for high-order surface representations and current expansions by using a novel set of high-order quasi curl-conforming basis functions. Like its predecessors, the HO-CMP can be seamlessly integrated into existing EFIE codes. Numerical results demonstrate that the linear systems of equations obtained using the proposed HO-CMP converge rapidly, regardless of the mesh density and of the order of the current expansion. © 2006 IEEE.

Investigation of avian influenza virus in poultry and wild birds due to novel avian-origin influenza A(H10N8) in Nanchang City, China.

Science.gov (United States)

Ni, Xiansheng; He, Fenglan; Hu, Maohong; Zhou, Xianfeng; Wang, Bin; Feng, Changhua; Wu, Yumei; Li, Youxing; Tu, Junling; Li, Hui; Liu, Mingbin; Chen, Haiying; Chen, Shengen

2015-01-01

Multiple reassortment events within poultry and wild birds had resulted in the establishment of another novel avian influenza A(H10N8) virus, and finally resulted in human death in Nanchang, China. However, there was a paucity of information on the prevalence of avian influenza virus in poultry and wild birds in Nanchang area. We investigated avian influenza virus in poultry and wild birds from live poultry markets, poultry countyards, delivery vehicles, and wild-bird habitats in Nanchang. We analyzed 1036 samples from wild birds and domestic poultry collected from December 2013 to February 2014. Original biological samples were tested for the presence of avian influenza virus using specific primer and probe sets of H5, H7, H9, H10 and N8 subtypes by real-time RT-PCR. In our analysis, the majority (97.98%) of positive samples were from live poultry markets. Among the poultry samples from chickens and ducks, AIV prevalence was 26.05 and 30.81%, respectively. Mixed infection of different HA subtypes was very common. Additionally, H10 subtypes coexistence with N8 was the most prevalent agent during the emergence of H10N8. This event illustrated a long-term surveillance was so helpful for pandemic preparedness and response. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Transmission of Haemorrhagic Fever with Renal Syndrome in China and the Role of Climate Factors: A Review

Directory of Open Access Journals (Sweden)

Alana Hansen

2015-04-01

Full Text Available Haemorrhagic fever with renal syndrome (HFRS is a rodent-borne disease that poses a serious public health threat in China. HFRS is caused by hantaviruses, mainly Seoul virus in urban areas and Hantaan virus in agricultural areas. Although preventive measures including vaccination programs and rodent control measures have resulted in a decline in cases in recent years, there has been an increase in incidence in some areas and new endemic areas have emerged. This review summarises the recent literature relating to the effects of climatic factors on the incidence of HFRS in China and discusses future research directions. Temperature, precipitation and humidity affect crop yields, rodent breeding patterns and disease transmission, and these can be influenced by a changing climate. Detailed surveillance of infections caused by Hantaan and Seoul viruses and further research on the viral agents will aid in interpretation of spatiotemporal patterns and a better understanding of the environmental and ecological drivers of HFRS amid China's rapidly urbanising landscape and changing climate.

[Emergence of new viruses in Asia: is climate change involved?].

Science.gov (United States)

Chastel, C

2004-11-01

Tropical Africa is not the only area where deadly viruses have recently emerged. In South-East Asia severe epidemics of dengue hemorrhagic fever started in 1954 and flu pandemics have originated from China such as the Asian flu (H2N2) in 1957, the Hong-Kong flu (H3N2) in 1968, and the Russian flu (H1N1) in 1977. However, it is especially during the last ten years that very dangerous viruses for mankind have repeatedly developed in Asia, with the occurrence of Alkhurma hemorrhagic fever in Saudi Arabia (1995), avian flu (H5N1) in Hong-Kong (1997), Nipah virus encephalitis in Malaysia (1998,) and, above all, the SARS pandemic fever from Southern China (2002). The evolution of these viral diseases was probably not directly affected by climate change. In fact, their emergential success may be better explained by the development of large industry poultry flocks increasing the risks of epizootics, dietary habits, economic and demographic constraints, and negligence in the surveillance and reporting of the first cases.

Distribution and molecular diversity of three cucurbit-infecting poleroviruses in China.

Science.gov (United States)

Shang, Qiao-xia; Xiang, Hai-ying; Han, Cheng-gui; Li, Da-wei; Yu, Jia-lin

2009-11-01

Cucurbit aphid-borne yellows virus (CABYV) and Melon aphid-borne yellows virus (MABYV) have been found to be associated with cucurbit yellowing disease in China. Our report identifies for the first time a third distinct polerovirus, tentatively named Suakwa aphid-borne yellows virus (SABYV), infecting Suakwa vegetable sponge. To better understand the distribution and molecular diversity of these three poleroviruses infecting cucurbits, a total of 214 cucurbitaceous crop samples were collected from 25 provinces in China, and were investigated by RT-PCR and sequencing. Of these, 108 samples tested positive for CABYV, while 40 samples from five provinces were positive for MABYV, and SABYV was detected in only 4 samples which were collected in the southern part of China. Forty-one PCR-amplified fragments containing a portion of the RdRp gene, intergenic NCR and CP gene were cloned and sequenced. Sequence comparisons showed that CABYV isolates shared 78.0-79.2% nucleotide sequence identity with MABYV isolates, and 69.7-70.8% with SABYV. Sequence identity between MABYV and SABYV was 73.3-76.5%. In contrast, the nucleotide identities within each species were 93.2-98.7% (CABYV), 98.1-99.9% (MABYV), and 96.1-98.6% (SABYV). Phylogenetic analyses revealed that the polerovirus isolates fit into three distinct groups, corresponding to the three species. The CABYV group could be further divided into two subgroups: the Asia subgroup and the Mediterranean subgroup, based on CP gene and partial RdRp gene sequences. Recombination analysis suggested that MABYV may be a recombinant virus.

Migration of rice planthoppers and their vectored re-emerging and novel rice viruses in East Asia.

Science.gov (United States)

Otuka, Akira

2013-10-28

This review examines recent studies of the migration of three rice planthoppers, Laodelphax striatellus, Sogatella furcifera, and Nilaparvata lugens, in East Asia. Laodelphax striatellus has recently broken out in Jiangsu province, eastern China. The population density in the province started to increase in the early 2000s and peaked in 2004. In 2005, Rice stripe virus (RSV) viruliferous rate of L. striatellus peaked at 31.3%. Since then, rice stripe disease spread severely across the whole province. Due to the migration of the RSV vectors, the rice stripe disease spread to neighboring countries Japan and Korea. An overseas migration of L. striatellus that occurred in 2008 was analyzed, when a slow-moving cold vortex, a type of low pressure system, reached western Japan from Jiangsu, carrying the insects into Japan. Subsequently the rice stripe diseases struck these areas in Japan severely. In Korea, similar situations occurred in 2009, 2011, and 2012. Their migration sources were also estimated to be in Jiangsu by backward trajectory analysis. Rice black-streaked dwarf virus, whose vector is L. striatellus, has recently re-emerged in eastern China, and the evidence for overseas migrations of the virus, just like the RSV's migrations, has been given. A method of predicting the overseas migration of L. striatellus has been developed by Japanese, Chinese, and Korean institutes. An evaluation of the prediction showed that this method properly predicted migration events that occurred in East Asia from 2008 to 2011. Southern rice black-streaked dwarf virus (SRBSDV) was first found in Guangdong province. Its vector is S. furcifera. An outbreak of SRBSDV occurred in southern China in 2009 and spread to Vietnam the same year. This disease and virus were also found in Japan in 2010. The epidemic triggered many migration studies to investigate concrete spring-summer migration routes in China, and the addition of migration sources for early arrivals in Guangdong and Guangxi

Viral etiologies of hospitalized acute lower respiratory infection patients in China, 2009-2013.

Directory of Open Access Journals (Sweden)

Luzhao Feng

Full Text Available BACKGROUND: Acute lower respiratory infections (ALRIs are an important cause of acute illnesses and mortality worldwide and in China. However, a large-scale study on the prevalence of viral infections across multiple provinces and seasons has not been previously reported from China. Here, we aimed to identify the viral etiologies associated with ALRIs from 22 Chinese provinces. METHODS AND FINDINGS: Active surveillance for hospitalized ALRI patients in 108 sentinel hospitals in 24 provinces of China was conducted from January 2009-September 2013. We enrolled hospitalized all-age patients with ALRI, and collected respiratory specimens, blood or serum collected for diagnostic testing for respiratory syncytial virus (RSV, human influenza virus, adenoviruses (ADV, human parainfluenza virus (PIV, human metapneumovirus (hMPV, human coronavirus (hCoV and human bocavirus (hBoV. We included 28,369 ALRI patients from 81 (of the 108 sentinel hospitals in 22 (of the 24 provinces, and 10,387 (36.6% were positive for at least one etiology. The most frequently detected virus was RSV (9.9%, followed by influenza (6.6%, PIV (4.8%, ADV (3.4%, hBoV (1.9, hMPV (1.5% and hCoV (1.4%. Co-detections were found in 7.2% of patients. RSV was the most common etiology (17.0% in young children aged <2 years. Influenza viruses were the main cause of the ALRIs in adults and elderly. PIV, hBoV, hMPV and ADV infections were more frequent in children, while hCoV infection was distributed evenly in all-age. There were clear seasonal peaks for RSV, influenza, PIV, hBoV and hMPV infections. CONCLUSIONS: Our findings could serve as robust evidence for public health authorities in drawing up further plans to prevent and control ALRIs associated with viral pathogens. RSV is common in young children and prevention measures could have large public health impact. Influenza was most common in adults and influenza vaccination should be implemented on a wider scale in China.

Current situation of H9N2 subtype avian influenza in China.

Science.gov (United States)

Gu, Min; Xu, Lijun; Wang, Xiaoquan; Liu, Xiufan

2017-09-15

In China, H9N2 subtype avian influenza outbreak is firstly reported in Guangdong province in 1992. Subsequently, the disease spreads into vast majority regions nationwide and has currently become endemic there. Over vicennial genetic evolution, the viral pathogenicity and transmissibility have showed an increasing trend as year goes by, posing serious threat to poultry industry. In addition, H9N2 has demonstrated significance to public health as it could not only directly infect mankind, but also donate partial or even whole cassette of internal genes to generate novel human-lethal reassortants like H5N1, H7N9, H10N8 and H5N6 viruses. In this review, we mainly focused on the epidemiological dynamics, biological characteristics, molecular phylogeny and vaccine strategy of H9N2 subtype avian influenza virus in China to present an overview of the situation of H9N2 in China.

Risk assessment on importation and autochthonous transmission of Zika virus disease in the mainland of China,2016%2016年我国内地寨卡病毒的输入和传播风险评估

Institute of Scientific and Technical Information of China (English)

涂文校; 马涛; 李昱; 刘起勇; 殷文武; 洪志恒; 李群; 倪大新

2016-01-01

寨卡病毒病在全球多地流行,可致小头畸形、格林-巴利综合征等神经系统疾病.2016年1～2月我国内地发现输入性病例10例,未发生本地传播.为明确2016年3～12月该病输入我国内地和传播的风险,根据我国内地登革热输入和传播规律、人员往来、伊蚊活动、人群密度等资料,通过定性和定量的风险评估,本文认为,我国内地将会继续发现输入性病例,如果2016年东南亚不流行,则预测2016年3～12月我国内地可能发现输入病例为8～68例;如果东南亚也出现类似往年登革热一样的流行规模,则预测2016年3～12月我国内地可能发现输入性病例为106～876例.6～10月是发生本地传播最有可能的时间;广东、云南、海南、福建、广西和浙江等省区是最可能发生本地传播的地区,其余有白纹伊蚊的省市可能出现本地传播,内蒙古、吉林、黑龙江、青海、宁夏、新疆等省区和辽宁、陕西、甘肃、西藏无伊蚊分布地区,全年均不会发生本地传播.建议各地继续做好输入性病例的监测,有本地传播风险的地区需加强蚊媒监测和控制,做好我国内地赴疫区旅行人员的健康提示,并根据国际疫情和研究进展动态开展风险评估.%Word Health Organizaiton has declared the clusters of microcephaly cases and other neurological disorders constituted a Public Health Emergency of International Concern on 1 Feberuary 2016,and there is increasing evidence that they are causal related with Zika virus.Zika virus disease has been identified in 41 countires and areas since 2015,and it is spreading to the other parts of the world.There were 10 imported cases of Zika virus disease detected in the mainland of China from January to February 2016,without autochthonous transmission.In order to identify the risk of importation and autochthonous transmission of Zika virus disease in the mainland of China from March to December,2016,we conducted

Direct economic burden and influencing factors in patients with hepatitis B virus related diseases in Jiangsu, China.

Science.gov (United States)

Zhang, Hua; Chao, Jianqian; Zhu, Liguo; Song, Long; Li, Xiyan; Liu, Pei

2015-03-01

The purpose of this study was to explore direct economic burden and its influencing factors in patients with hepatitis B virus (HBV) related diseases. Time phasing continuous sampling was used to select patients from August 1, 2012, to December 31, 2012, in 3 county hospitals of 3 model regions in Jiangsu Province, China. A total of 436 outpatients and 196 inpatients were observed. The average direct economic burden of HBV-associated admission was US$107.11 for outpatients, and drug fees accounted for 74%; the burden was US$3193.47 for inpatients, and the direct medical costs accounted for 96%. Multivariate linear regression analysis showed that drug fee, examination fee, and antiviral therapy were influencing factors for outpatients, while hospitalization stay, drug ratio, and patient's age were influencing factors for inpatients. It can be concluded that the direct economic burden of patients with HBV-related diseases was high compared to their household income. Measures should be taken to reduce the economic burden of patients. © 2014 APJPH.

Canine distemper outbreak in rhesus monkeys, China.

Science.gov (United States)

Qiu, Wei; Zheng, Ying; Zhang, Shoufeng; Fan, Quanshui; Liu, Hua; Zhang, Fuqiang; Wang, Wei; Liao, Guoyang; Hu, Rongliang

2011-08-01

Since 2006, canine distemper outbreaks have occurred in rhesus monkeys at a breeding farm in Guangxi, People's Republic of China. Approximately 10,000 animals were infected (25%-60% disease incidence); 5%-30% of infected animals died. The epidemic was controlled by vaccination. Amino acid sequence analysis of the virus indicated a unique strain.

History of Swine influenza viruses in Asia.

Science.gov (United States)

Zhu, Huachen; Webby, Richard; Lam, Tommy T Y; Smith, David K; Peiris, Joseph S M; Guan, Yi

2013-01-01

The pig is one of the main hosts of influenza A viruses and plays important roles in shaping the current influenza ecology. The occurrence of the 2009 H1N1 pandemic influenza virus demonstrated that pigs could independently facilitate the genesis of a pandemic influenza strain. Genetic analyses revealed that this virus was derived by reassortment between at least two parent swine influenza viruses (SIV), from the northern American triple reassortant H1N2 (TR) and European avian-like H1N1 (EA) lineages. The movement of live pigs between different continents and subsequent virus establishment are preconditions for such a reassortment event to occur. Asia, especially China, has the largest human and pig populations in the world, and seems to be the only region frequently importing pigs from other continents. Virological surveillance revealed that not only classical swine H1N1 (CS), and human-origin H3N2 viruses circulated, but all of the EA, TR and their reassortant variants were introduced into and co-circulated in pigs in this region. Understanding the long-term evolution and history of SIV in Asia would provide insights into the emergence of influenza viruses with epidemic potential in swine and humans.

Isolation of H5N6, H7N9 and H9N2 avian influenza A viruses from air sampled at live poultry markets in China, 2014 and 2015.

Science.gov (United States)

Zhou, Jie; Wu, Jie; Zeng, Xianqiao; Huang, Guofeng; Zou, Lirong; Song, Yingchao; Gopinath, Divya; Zhang, Xin; Kang, Min; Lin, Jinyan; Cowling, Benjamin J; Lindsley, William G; Ke, Changwen; Peiris, Joseph Sriyal Malik; Yen, Hui-Ling

2016-09-01

Zoonotic infections by avian influenza viruses occur at the human-poultry interface, but the modes of transmission have not been fully investigated. We assessed the potential for airborne and fomite transmission at live poultry markets in Guangzhou city and in Hong Kong Special Administrative Region (SAR), China, during 2014 and 2015. Viral genome and infectious avian influenza A viruses of H5N6, H7N9, and H9N2 subtypes were detected predominantly from particles larger or equal to 1 μm in diameter in the air sampled with cyclone-based bioaerosol samplers at the live poultry markets in Guangzhou. Influenza A(H9N2) viruses were ubiquitously isolated every month during the study period from air and environmental swabs, and different lineages of H9N2 virus were isolated from markets where chickens and minor land-based poultry were sold. The use of de-feathering devices increased the quantity of virus-laden airborne particles while market closure reduced the amount of such particles. The results highlight the possibility of airborne transmission of avian influenza viruses among poultry or from poultry to humans within such settings. This may explain epidemiological observations in which some patients with H7N9 infection reported being in markets but no direct contact with live poultry or poultry stalls. This article is copyright of The Authors, 2016.

Fatal canine distemper virus infection of giant pandas in China.

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Feng, Na; Yu, Yicong; Wang, Tiecheng; Wilker, Peter; Wang, Jianzhong; Li, Yuanguo; Sun, Zhe; Gao, Yuwei; Xia, Xianzhu

2016-06-16

We report an outbreak of canine distemper virus (CDV) infection among endangered giant pandas (Ailuropoda melanoleuca). Five of six CDV infected giant pandas died. The surviving giant panda was previously vaccinated against CDV. Genomic sequencing of CDV isolated from one of the infected pandas (giant panda/SX/2014) suggests it belongs to the Asia-1 cluster. The hemagglutinin protein of the isolated virus and virus sequenced from lung samples originating from deceased giant pandas all possessed the substitutions V26M, T213A, K281R, S300N, P340Q, and Y549H. The presence of the Y549H substitution is notable as it is found at the signaling lymphocytic activation molecule (SLAM) receptor-binding site and has been implicated in the emergence of highly pathogenic CDV and host switching. These findings demonstrate that giant pandas are susceptible to CDV and suggest that surveillance and vaccination among all captive giant pandas are warranted to support conservation efforts for this endangered species.

Herd-level prevalence and associated risk factors for Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhoea virus in commercial dairy and beef cattle in eastern, northern and northeastern China.

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Sun, Wu-Wen; Meng, Qing-Feng; Cong, Wei; Shan, Xiao-Feng; Wang, Chun-Feng; Qian, Ai-Dong

2015-11-01

Although the seroprevalence of Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhea virus infection in cattle have been reported in some areas in China, most of them were conducted with small number of cattle samples and very limited districts and neglected the assessment of herd management factors associated with herd-level prevalence of these pathogen infections. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the animal-level and herd-level seroprevalence and identify herd-level risk factors associated with these pathogen infections in 4487 cattle from 134 herds in five provinces (Heilongjiang, Jilin, Liaoning, Shandong, Hebei) and Inner Mongolia Autonomous Region of China. At animal level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and bovine viral diarrhoea virus (BVDV) was 10.48, 17.14, 11.92 and 50.10%, respectively. At herd level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and BVDV was 27.16, 29.10, 37.31 and 40.30%, respectively. Multivariate analysis of these characteristics showed that source of water and presence of felids were significantly associated with T. gondii infection in the studied cattle herds. Source of water was significantly associated with N. caninum infection in the studied cattle herds. While herd size and management system were significantly associated with BVDV infection in the studied cattle herds, this is the first report of herd-level prevalence and associated risk factors of T. gondii, N. caninum, C. abortus and BVDV infection in cattle in China.

De novo Genome Assembly and Single Nucleotide Variations for Soybean Mosaic Virus Using Soybean Seed Transcriptome Data

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Yeonhwa Jo

2017-10-01

Full Text Available Soybean is the most important legume crop in the world. Several diseases in soybean lead to serious yield losses in major soybean-producing countries. Moreover, soybean can be infected by diverse viruses. Recently, we carried out a large-scale screening to identify viruses infecting soybean using available soybean transcriptome data. Of the screened transcriptomes, a soybean transcriptome for soybean seed development analysis contains several virus-associated sequences. In this study, we identified five viruses, including soybean mosaic virus (SMV, infecting soybean by de novo transcriptome assembly followed by blast search. We assembled a nearly complete consensus genome sequence of SMV China using transcriptome data. Based on phylogenetic analysis, the consensus genome sequence of SMV China was closely related to SMV isolates from South Korea. We examined single nucleotide variations (SNVs for SMVs in the soybean seed transcriptome revealing 780 SNVs, which were evenly distributed on the SMV genome. Four SNVs, C-U, U-C, A-G, and G-A, were frequently identified. This result demonstrated the quasispecies variation of the SMV genome. Taken together, this study carried out bioinformatics analyses to identify viruses using soybean transcriptome data. In addition, we demonstrated the application of soybean transcriptome data for virus genome assembly and SNV analysis.

Clinical analysis of the first case with imported Zika virus disease in China%中国大陆首例输入性寨卡病毒病的临床分析

Institute of Scientific and Technical Information of China (English)

钟渊斌; 李小鹏; 张伦理; 曾莉萍; 邓宜楚

2016-01-01

目的 了解寨卡病毒病的流行病学特点及临床特征,提高对寨卡病毒病的防治能力.方法 回顾性报道及分析中国大陆首例输入性寨卡病毒病的临床资料,并就近年人感染寨卡病毒的流行特点作一阐述.结果 本例患者为中国大陆首例输入性寨卡病毒病,具有典型临床特点,流行病学史较明确,所有接触者均寨卡病毒核酸检测阴性.检索文献,寨卡病毒在非洲、亚洲、美洲等40多个国家有传播的证据,患者一般临床症状较轻,主要预防措施包括防蚊、控蚊和提高个人防护意识.结论 人感染寨卡病毒多隐性感染,少部分发病,经对症、支持等治疗后一般预后良好.%Objective To understand the epidemiological characteristics and clinical features of Zika virus disease,and to improve its prophylaxis and treatment.Methods The first case with imported Zika virus disease in China was retrospectively reported and analyzed.The literature of Zika virus infection in human was reviewed.Results This patient was the first case with imported Zika virus disease in China who presented with typical clinical characteristics and had clear epidemiological history.All the contacts were test negative for Zika virus nucleic acid.Literature retrieval showed evidence of Zika virus propagation in more than 40 countries in Africa,Asia,and Americas.The majority of patients presented with mild symptoms and the main prevention measures included mosquito control and improved awareness of personal protection.Conclusions Human infected with Zika virus often shows recessive infection.Only a small part develop disease and have generally good prognosis with supportive treatment.

Proof-of-principle that a decoy virus protects oncolytic measles virus against neutralizing antibodies

OpenAIRE

Xu C; Goß AV; Dorneburg C; Debatin KM; Wei J; Beltinger C

2018-01-01

Chun Xu,1,2,* Annika Verena Goß,1,* Carmen Dorneburg,1 Klaus-Michael Debatin,1 Jiwu Wei,2 Christian Beltinger1 1Department of Pediatrics and Adolescent Medicine, Section of Experimental Pediatric Oncology, University Medical Center Ulm, Ulm, Germany; 2Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, China *These authors contributed equally to this work Background: Attenuated oncolytic measles virus (OMV) is a promising antitumor agent in early-phase cl...

Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

KAUST Repository

Brown, J.K.; Mills-Lujan, K.; Idris, Ali

2011-01-01

divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade

Molecular characterization of two genotypes of a new polerovirus infecting brassicas in China.

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Xiang, Hai-Ying; Dong, Shu-Wei; Shang, Qiao-Xia; Zhou, Cui-Ji; Li, Da-Wei; Yu, Jia-Lin; Han, Cheng-Gui

2011-12-01

The genomic RNA sequences of two genotypes of a brassica-infecting polerovirus from China were determined. Sequence analysis revealed that the virus was closely related to but significantly different from turnip yellows virus (TuYV). This virus and other poleroviruses, including TuYV, had less than 90% amino acid sequence identity in all gene products except the coat protein. Based on the molecular criterion (>10% amino acid sequence difference) for species demarcation in the genus Polerovirus, the virus represents a distinct species for which the name Brassica yellows virus (BrYV) is proposed. Interestingly, there were two genotypes of BrYV, which mainly differed in the 5'-terminal half of the genome.

Complete genome analysis of dengue virus type 3 isolated from the 2013 dengue outbreak in Yunnan, China.

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Wang, Xiaodan; Ma, Dehong; Huang, Xinwei; Li, Lihua; Li, Duo; Zhao, Yujiao; Qiu, Lijuan; Pan, Yue; Chen, Junying; Xi, Juemin; Shan, Xiyun; Sun, Qiangming

2017-06-15

In the past few decades, dengue has spread rapidly and is an emerging disease in China. An unexpected dengue outbreak occurred in Xishuangbanna, Yunnan, China, resulting in 1331 patients in 2013. In order to obtain the complete genome information and perform mutation and evolutionary analysis of causative agent related to this largest outbreak of dengue fever. The viruses were isolated by cell culture and evaluated by genome sequence analysis. Phylogenetic trees were then constructed by Neighbor-Joining methods (MEGA6.0), followed by analysis of nucleotide mutation and amino acid substitution. The analysis of the diversity of secondary structure for E and NS1 protein were also performed. Then selection pressures acting on the coding sequences were estimated by PAML software. The complete genome sequences of two isolated strains (YNSW1, YNSW2) were 10,710 and 10,702 nucleotides in length, respectively. Phylogenetic analysis revealed both strain were classified as genotype II of DENV-3. The results indicated that both isolated strains of Xishuangbanna in 2013 and Laos 2013 stains (KF816161.1, KF816158.1, LC147061.1, LC147059.1, KF816162.1) were most similar to Bangladesh (AY496873.2) in 2002. After comparing with the DENV-3SS (H87) 62 amino acid substitutions were identified in translated regions, and 38 amino acid substitutions were identified in translated regions compared with DENV-3 genotype II stains Bangladesh (AY496873.2). 27(YNSW1) or 28(YNSW2) single nucleotide changes were observed in structural protein sequences with 7(YNSW1) or 8(YNSW2) non-synonymous mutations compared with AY496873.2. Of them, 4 non-synonymous mutations were identified in E protein sequences with (2 in the β-sheet, 2 in the coil). Meanwhile, 117(YNSW1) or 115 (YNSW2) single nucleotide changes were observed in non-structural protein sequences with 31(YNSW1) or 30 (YNSW2) non-synonymous mutations. Particularly, 14 single nucleotide changes were observed in NS1 sequences with 4/14 non

Case-control study of risk factors for human infection with avian influenza A(H7N9) virus in Shanghai, China, 2013.

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Li, J; Chen, J; Yang, G; Zheng, Y X; Mao, S H; Zhu, W P; Yu, X L; Gao, Y; Pan, Q C; Yuan, Z A

2015-07-01

The first human infection with avian influenza A(H7N9) virus was reported in Shanghai, China in March 2013. An additional 32 cases of human H7N9 infection were identified in the following months from March to April 2013 in Shanghai. Here we conducted a case-control study of the patients with H7N9 infection (n = 25) using controls matched by age, sex, and residence to determine risk factors for H7N9 infection. Our findings suggest that chronic disease and frequency of visiting a live poultry market (>10 times, or 1-9 times during the 2 weeks before illness onset) were likely to be significantly associated with H7N9 infection, with the odds ratios being 4.07 [95% confidence interval (CI) 1.32-12.56], 10.61 (95% CI 1.85-60.74), and 3.76 (95% CI 1.31-10.79), respectively. Effective strategies for live poultry market control should be reinforced and ongoing education of the public is warranted to promote behavioural changes that can help to eliminate direct or indirect contact with influenza A(H7N9) virus.

Evaluation of Commercial Diagnostic Assays for the Specific Detection of Avian Influenza A (H7N9) Virus RNA Using a Quality-Control Panel and Clinical Specimens in China

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Chen, Suhong; Wang, Dayan; Li, Changgui; Wu, Xing; Li, Lili; Bai, Dongting; Zhang, Chuntao; Wang, Junzhi

2015-01-01

A novel avian influenza A H7N9-subtype virus emerged in China in 2013 and threatened global public health. Commercial kits that specifically detect avian influenza A (H7N9) virus RNA are urgently required to prepare for the emergence and potential pandemic of this novel influenza virus. The safety and effectiveness of three commercial molecular diagnostic assays were evaluated using a quality-control panel and clinical specimens collected from over 90 patients with confirmed avian influenza A (H7N9) virus infections. The analytical performance evaluation showed that diverse influenza H7N9 viruses can be detected with high within- and between-lot reproducibility and without cross-reactivity to other influenza viruses (H1N1 pdm09, seasonal H1N1, H3N2, H5N1 and influenza B). The detection limit of all the commercial assays was 2.83 Log10 copies/μl [0.7 Log10TCID50/mL of avian influenza A (H7N9) virus strain A/Zhejiang/DTID-ZJU01/2013], which is comparable to the method recommended by the World Health Organization (WHO). In addition, using a WHO-Chinese National Influenza Center (CNIC) method as a reference for clinical evaluation, positive agreement of more than 98% was determined for all of the commercial kits, while negative agreement of more than 99% was observed. In conclusion, our findings provide comprehensive evidence for the high performance of three commercial diagnostic assays and suggest the application of these assays as rapid and effective diagnostic tools for avian influenza A (H7N9) virus in the routine clinical practice of medical laboratories. PMID:26361351

Canine Distemper Outbreak in Rhesus Monkeys, China

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Qiu, Wei; Zheng, Ying; Zhang, Shoufeng; Fan, Quanshui; Liu, Hua; Zhang, Fuqiang; Wang, Wei; Liao, Guoyang

2011-01-01

Since 2006, canine distemper outbreaks have occurred in rhesus monkeys at a breeding farm in Guangxi, People’s Republic of China. Approximately 10,000 animals were infected (25%–60% disease incidence); 5%–30% of infected animals died. The epidemic was controlled by vaccination. Amino acid sequence analysis of the virus indicated a unique strain. PMID:21801646

Virome profiling of bats from Myanmar by metagenomic analysis of tissue samples reveals more novel Mammalian viruses.

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Biao He

Full Text Available Bats are reservoir animals harboring many important pathogenic viruses and with the capability of transmitting these to humans and other animals. To establish an effective surveillance to monitor transboundary spread of bat viruses between Myanmar and China, complete organs from the thorax and abdomen from 853 bats of six species from two Myanmar counties close to Yunnan province, China, were collected and tested for their virome through metagenomics by Solexa sequencing and bioinformatic analysis. In total, 3,742,314 reads of 114 bases were generated, and over 86% were assembled into 1,649,512 contigs with an average length of 114 bp, of which 26,698 (2% contigs were recognizable viral sequences belonging to 24 viral families. Of the viral contigs 45% (12,086/26,698 were related to vertebrate viruses, 28% (7,443/26,698 to insect viruses, 27% (7,074/26,698 to phages and 95 contigs to plant viruses. The metagenomic results were confirmed by PCR of selected viruses in all bat samples followed by phylogenetic analysis, which has led to the discovery of some novel bat viruses of the genera Mamastrovirus, Bocavirus, Circovirus, Iflavirus and Orthohepadnavirus and to their prevalence rates in two bat species. In conclusion, the present study aims to present the bat virome in Myanmar, and the results obtained further expand the spectrum of viruses harbored by bats.

Assessment of the knowledge, attitude and practices about Human Papilloma Virus vaccine among the nurses working in a tertiary hospital in China: A cross-sectional descriptive study.

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Zhang, Jun-Mei; Zhao, Qi-Mei; Zhang, Lei-Ming

2017-02-01

To assess the knowledge about human papilloma virus infection and vaccine, to ascertain the attitude and practices about the vaccine, and to ascertain the determinants preventing people from getting themselves vaccinated. The cross-sectional descriptive study was conducted from June to August 2015 in Henan Provincial People's Hospital, Henan, China, and comprised all the nursing staff including nursing students. A piloted semi-structured questionnaire was used for collecting data. Statistical analysis was done using SPSS 18. Of the 308 subjects, 190(61.6%) were professional nurses and 118(38.3%) were nursing students. The mean age of the nurses was 36.7±6.2 years and that of the students was 20.4±2.1 years. Overall, 254(82.5%) subjects were aware about the existence of human papilloma virus vaccine; 241(94.9%) thought that the vaccine could effectively prevent the development of cervical cancer; and 108(61.4%) were reluctant to get vaccinated because the vaccine was expensive. There is a need to address the myths and misconceptions associated with vaccines in order to improve the acceptance of human papilloma virus vaccine among them.

Identification of a natural human serotype 3 parainfluenza virus

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Wang Xiao-Jing

2011-02-01

Full Text Available Abstract Parainfluenza virus is an important pathogen threatening the health of animals and human, which brings human many kinds of disease, especially lower respiratory tract infection involving infants and young children. In order to control the virus, it is necessary to fully understand the molecular basis resulting in the genetic diversity of the virus. Homologous recombination is one of mechanisms for the rapid change of genetic diversity. However, as a negative-strand virus, it is unknown whether the recombination can naturally take place in human PIV. In this study, we isolated and identified a mosaic serotype 3 human PIV (HPIV3 from in China, and also provided several putative PIV mosaics from previous reports to reveal that the recombination can naturally occur in the virus. In addition, two swine PIV3 isolates transferred from cattle to pigs were found to have mosaic genomes. These results suggest that homologous recombination can promote the genetic diversity and potentially bring some novel biologic characteristics of HPIV.

Microbiological Food Safety Surveillance in China

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Xiaoyan Pei

2015-08-01

Full Text Available Microbiological food safety surveillance is a system that collects data regarding food contamination by foodborne pathogens, parasites, viruses, and other harmful microbiological factors. It helps to understand the spectrum of food safety, timely detect food safety hazards, and provide relevant data for food safety supervision, risk assessment, and standards-setting. The study discusses the microbiological surveillance of food safety in China, and introduces the policies and history of the national microbiological surveillance system. In addition, the function and duties of different organizations and institutions are provided in this work, as well as the generation and content of the surveillance plan, quality control, database, and achievement of the microbiological surveillance of food safety in China.

Multiple introductions of serotype O foot-and-mouth disease viruses into East Asia in 2010-2011.

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Valdazo-González, Begoña; Timina, Anna; Scherbakov, Alexey; Abdul-Hamid, Nor Faizah; Knowles, Nick J; King, Donald P

2013-09-05

Foot-and-mouth disease virus (FMDV) is a highly contagious and genetically variable virus. Sporadic introductions of this virus into FMD-free countries may cause outbreaks with devastating consequences. In 2010 and 2011, incursions of the FMDV O/SEA/Mya-98 strain, normally restricted to countries in mainland Southeast Asia, caused extensive outbreaks across East Asia. In this study, 12 full genome FMDV sequences for representative samples collected from the People's Republic of China (PR China) including the Hong Kong Special Administrative Region (SAR), the Republic of Korea, the Democratic People's Republic of Korea, Japan, Mongolia and The Russian Federation were generated and compared with additional contemporary sequences from viruses within this lineage. These complete genomes were 8119 to 8193 nucleotides in length and differed at 1181 sites, sharing a nucleotide identity ≥ 91.0% and an amino acid identity ≥ 96.6%. An unexpected deletion of 70 nucleotides within the 5'-untranslated region which resulted in a shorter predicted RNA stem-loop for the S-fragment was revealed in two sequences from PR China and Hong Kong SAR and five additional related samples from the region. Statistical parsimony and Bayesian phylogenetic analysis provide evidence that these outbreaks in East Asia were generated by two independent introductions of the O/SEA/Mya-98 lineage sometime between August 2008 and March 2010. The rapid emergence of these viruses from Southeast Asia highlights the importance of adopting approaches to closely monitor the spread of this lineage that now poses a threat to livestock industries in other regions.

Fatal canine distemper virus infection of giant pandas in China

Science.gov (United States)

Feng, Na; Yu, Yicong; Wang, Tiecheng; Wilker, Peter; Wang, Jianzhong; Li, Yuanguo; Sun, Zhe; Gao, Yuwei; Xia, Xianzhu

2016-01-01

We report an outbreak of canine distemper virus (CDV) infection among endangered giant pandas (Ailuropoda melanoleuca). Five of six CDV infected giant pandas died. The surviving giant panda was previously vaccinated against CDV. Genomic sequencing of CDV isolated from one of the infected pandas (giant panda/SX/2014) suggests it belongs to the Asia-1 cluster. The hemagglutinin protein of the isolated virus and virus sequenced from lung samples originating from deceased giant pandas all possessed the substitutions V26M, T213A, K281R, S300N, P340Q, and Y549H. The presence of the Y549H substitution is notable as it is found at the signaling lymphocytic activation molecule (SLAM) receptor-binding site and has been implicated in the emergence of highly pathogenic CDV and host switching. These findings demonstrate that giant pandas are susceptible to CDV and suggest that surveillance and vaccination among all captive giant pandas are warranted to support conservation efforts for this endangered species. PMID:27310722

Genomic 3' terminal sequence comparison of three isolates of rabbit haemorrhagic disease virus.

Science.gov (United States)

Milton, I D; Vlasak, R; Nowotny, N; Rodak, L; Carter, M J

1992-05-15

Comparison of sequence data is necessary in older to investigate virus origins, identify features common to virulent strains, and characterize genomic organization within virus families. A virulent caliciviral disease of rabbits recently emerged in China. We have sequenced 1100 bases from the 3' ends of two independent European isolates of this virus, and compared these with previously determined calicivirus sequences. Rabbit caliciviruses were closely related, despite the different countries in which isolation was made. This supports the rapid spread of a new virus across Europe. The capsid protein sequences of these rabbit viruses differ markedly from those determined for feline calicivirus, but a hypothetical 3' open reading frame is relatively well conserved between the caliciviruses of these two different hosts and argues for a functional role.

Seroepidemiology of hepatitis B virus infection in 2 million men aged 21-49 years in rural China: a population-based, cross-sectional study.

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Liu, Jue; Zhang, Shikun; Wang, Qiaomei; Shen, Haiping; Zhang, Man; Zhang, Yiping; Yan, Donghai; Liu, Min

2016-01-01

Hepatitis B virus (HBV) infection is highly endemic (7-8% prevalence) in rural China, causing high mortality and societal burden. Data from men of reproductive age is scarce and last reported in 2006. We assessed the seroepidemiology of men in rural China, aiming to provide updated baseline data for the prevalence of HBV infection. We established prevalence of HBV infection from data gathered through a nationwide population-based study of Chinese rural men aged 21-49 years. Data were obtained from a physical check-up programme for couples of reproductive age, the National Free Preconception Health Examination Project, that covered 31 provinces from 2010-12. We tested serological samples with ELISA and categorised participants' HBV status based on presence of HBsAg, anti-HBV core antibody (anti-HBc), and anti-HBV surface antibody (anti-HBs). 2 030 083 men were recruited into the database from Jan 1, 2010, to Dec 31, 2012, and 1 966 013 men provided serum samples for analysis. 124 274 men (6%) tested positive for HBsAg, 178 559 (9%) tested positive for anti-HBc, and 583 923 (30%) tested positive for anti-HBs. Isolated anti-HBs (an indicator of vaccine-mediated immunity) were present in 527 566 men (27%). And 1 234 127 men (63%) were negative for all HBV makers (susceptible population). HBsAg prevalence was higher in men aged 25-39 years (6·35-6·47%) than in other age groups (5·54-5·78%; pChina than in the central or western regions (all pChina has changed from highly endemic into intermediate endemic in the past two decades. However, the absolute number of HBV-infected men and the susceptible population is still very large. Chinese Association of Maternal and Child Health Studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spatiotemporal Scan and Age-Period-Cohort Analysis of Hepatitis C Virus in Henan, China: 2005-2012.

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Fangfang Chen

Full Text Available Studies have shown that hepatitis C virus (HCV infection increased during the past decades in China. However, little evidence is available on when, where, and who were infected with HCV. There are gaps in knowledge on the epidemiological burden and evolution of the HCV epidemic in China.Data on HCV cases were collected by the disease surveillance system from 2005 to 2012 to explore the epidemic in Henan province. Spatiotemporal scan statistics and age-period-cohort (APC model were used to examine the effects of age, period, birth cohort, and spatiotemporal clustering.177,171 HCV cases were reported in Henan province between 2005 and 2012. APC modelling showed that the HCV reported rates significantly increased in people aged > 50 years. A moderate increase in HCV reported rates was observed for females aged about 25 years. HCV reported rates increased over the study period. Infection rates were greatest among people born between 1960 and 1980. People born around 1970 had the highest relative risk of HCV infection. Women born between 1960 and 1980 had a five-fold increase in HCV infection rates compared to men, for the same birth cohort. Spatiotemporal mapping showed major clustering of cases in northern Henan, which probably evolved much earlier than other areas in the province.Spatiotemporal mapping and APC methods are useful to help delineate the evolution of the HCV epidemic. Birth cohort should be part of the criteria screening programmes for HCV in order to identify those at highest risk of infection and unaware of their status. As Henan is unique in the transmission route for HCV, these methods should be used in other high burden provinces to help identify subpopulations at risk.

A novel complex A/C/G intergenotypic recombinant of hepatitis B virus isolated in southern China.

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Heling Su

Full Text Available Hepatitis B virus (HBV genotypes and subgenotypes may vary in geographical distribution and virological features. Previous investigations, including ours, showed that HBV genotypes B and C were respectively predominant in South and North China, while genotypes A and D were infrequently detected and genotype G was not found. In this study, a novel A/C/G intergenotype was identified in patients with chronic HBV infection in Guilin, a city in southern China. Initial phylogenetic analysis based on the S gene suggested the HBV recombinant to be genotype G. However, extended genotyping based on the entire HBV genome indicated it to be an A/C/G intergenotype with a closer relation to genotype C. Breakpoint analysis using the SIMPLOT program revealed that the recombinant had a recombination with a arrangement of genotypes A, G, A and C fragments. Compared with the HBV recombinants harboring one or two genotype G fragments found in Asian countries, this Guilin recombinant was highly similar to the Vietnam (98-99% and Long An recombinants (96-99%, but had a relatively low similarity to the Thailand one (89%. Unlike those with the typical genotype G of HBV, the patients with the Guilin recombinant were seropositive for HBeAg. Moreover, a relatively high HBV DNA viral load (>2 × 10(6 IU/ml was detected in the patients, and the analysis of viral replication capacity showed that the Guilin recombinant strains had a competent replication capacity similar to genotypes B and C strains. These findings can aid in not only the clarification of the phylogenetic origin of the HBV recombinants with the genotype G fragment found in Asian countries, but also the understanding of the virological properties of these complicated HBV recombinants.

Evaluation of a genetically modified foot-and-mouth disease virus vaccine candidate generated by reverse genetics

Science.gov (United States)

2012-01-01

Background Foot-and-mouth disease (FMD) is the most economically important and highly contagious disease of cloven-hoofed animals worldwide. Control of the disease has been mainly based on large-scale vaccinations with whole-virus inactivated vaccines. In recent years, a series of outbreaks of type O FMD occurred in China (including Chinese Taipei, Chinese Hong Kong) posed a tremendous threat to Chinese animal husbandry. Its causative agent, type O FMDV, has evolved into three topotypes (East–South Asia (ME-SA), Southeast Asia (SEA), Cathay (CHY)) in these regions, which represents an important obstacle to disease control. The available FMD vaccine in China shows generally good protection against ME-SA and SEA topotype viruses infection, but affords insufficient protection against some variants of the CHY topotype. Therefore, the choice of a new vaccine strain is of fundamental importance. Results The present study describes the generation of a full-length infectious cDNA clone of FMDV vaccine strain and a genetically modified virus with some amino acid substitutions in antigenic sites 1, 3, and 4, based on the established infectious clone. The recombinant viruses had similar growth properties to the wild O/HN/CHA/93 virus. All swine immunized with inactivated vaccine prepared from the O/HN/CHA/93 were fully protected from challenge with the viruses of ME-SA and SEA topotypes and partially protected against challenge with the virus of CHY topotype at 28 days post-immunization. In contrast, the swine inoculated with the genetically modified vaccine were completely protected from the infection of viruses of the three topotypes. Conclusions Some amino acid substitutions in the FMDV vaccine strain genome did not have an effect on the ability of viral replication in vitro. The vaccine prepared from genetically modified FMDV by reverse genetics significantly improved the protective efficacy to the variant of the CHY topotype, compared with the wild O/HN/CHA/93 virus