Ranunculus latent virus: a strain of artichoke latent virus or a new macluravirus infecting artichoke?

An elongated virus was isolated from artichoke crops in Liguria, and a 700-bp fragment was amplified by RT-PCR using oligonucleotides to detect members of the family Potyviridae. Comparison of fragment sequences showed 98% identity at the nucleotide level with the ranunculus isolate of the macluravirus Ranunculus latent virus (RaLV). RaLV was then detected by DAS-ELISA in symptomatic and asymptomatic artichoke plants from Liguria, Sardinia and Latium. The sequence of a 5.5-kb region was assembled from a cDNA library, and a 500-bp NIa fragment showed 80% identity to Artichoke latent virus.     

Protective efficacy of a recombinant bacterial artificial chromosome clone of a very virulent Marek’s disease virus containing a reticuloendotheliosis virus long terminal repeat

Marek’s disease virus (MDV), an alphaherpesvirus, causes Marek’s disease (MD), a lymphoproliferative disease in poultry characterized by T-cell lymphomas, nerve lesions, and mortality. Vaccination is used worldwide to control MD, but increasingly virulent field strains can overcome this protection, driving a need to create new vaccines. Previous studies revealed that insertion of reticuloendotheliosis virus (REV) long terminal repeat (LTR) into a bacterial artificial chromosome (BAC) clone of a very virulent strain of MDV, Md5, rendered the resultant recombinant virus, rMd5 REV-LTR BAC, fully attenuated in maternal antibody positive (Mab+) chickens at passage 40. In the current study, the protective efficacy of rMd5 REV-LTR BAC was evaluated. First, passage 70 was identified as being fully attenuated in maternal antibody negative chickens and chosen as the optimal passage level for use in protective efficacy studies. Second, three protective efficacy trials were conducted comparing the rMd5 REV-LTR p70 BAC to the CVI988/Rispens vaccine. Groups of Mab+ and Mab? 15I₅?×?7₁ chickens were vaccinated in ovo at 18 days of embryonation or intra-abdominally at day of hatch, and challenged at 5 days post-hatch with the vv+MDV strain 686. Vaccination at day of hatch and in ovo with rMd5 REV-LTR p70 BAC protected chickens against MDV-induced bursa and thymic atrophy, but did not provide the same level of protection against MD tumours as that afforded by the commercial vaccine, CVI988/Rispens.     

Is chronic fatigue syndrome caused by a rare brain infection of a common,normally benign virus?

Chronic fatigue syndrome (CFS) is a disabling disease of unknown aetiology. A variety of factors have been suggested as possible causes. Although the symptoms and clinical findings are heterogeneous, the syndrome is sufficiently distinct, at least in relation to the more obvious cases, that a common explanation seems likely. In this paper, it is proposed that the disease is caused by a ubiquitous, but normally benign virus, e.g., one of the circoviruses. Circoviruses are chronically present in a majority of people, but are rarely tested for diagnostically. Normally these viruses do not penetrate the blood-brain barrier, but exceptions have been reported, and related viruses cause disease in the central nervous system of animals. The flu-like illness that often precedes the onset of CFS may either suppress immune function, causing an increased viremia, and/or lower the blood-brain barrier. In both cases the result may be that a virus already present in the blood enters the brain. It is well known that zoonotic viruses typically are more malignant than viruses with a long history of host-virus evolution. Similarly, a virus reaching an unfamiliar organ may cause particular problems.     

Adiponectin, a downstream target gene of peroxisome proliferator-activated receptor γ, controls hepatitis B virus replication

In this study, HepG2-hepatitis B virus (HBV)-stable cells that did not overexpress HBx and HBx-deficient mutant-transfected cells were analyzed for their expression of HBV-induced, upregulated adipogenic and lipogenic genes. The mRNAs of CCAAT enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), adiponectin, liver X receptor α (LXRα), sterol regulatory element binding protein 1c (SREBP1c), and fatty acid synthase (FAS) were expressed at higher levels in HepG2-HBV and lamivudine-treated stable cells and HBx-deficient mutant-transfected cells than in the HepG2 cells. Lamivudine treatment reduced the mRNA levels of PPARγ and C/EBPα. Conversely, HBV replication was upregulated by adiponectin and PPARγ agonist rosiglitazone treatments and was downregulated by adiponectin siRNAs. Collectively, our results demonstrate that HBV replication and/or protein expression, even in the absence of HBx, upregulated adipogenic or lipogenic genes, and that the control of adiponectin might prove useful as a therapeutic modality for the treatment of chronic hepatitis B.     

Hepatitis B virus S gene enhances immune responses of a multiple-epitope DNA construct of hepatitis C virus in mice

Hepatitis C virus (HCV) is a major causative agent of acute and chronic hepatitis and mainlytransmitted by blood routes. It is estimated thatthere are 170 million HCV infected individualsworldwide, and so far, interferon γ(IFN γ) com bined with ribavirin treatment is a commonly ac cepted therapeutic strategy. However, only about40% of treated patients develop long term respons es[1]. The hypervariable region 1(HVR1) of theHCV E2 envelope protein is critically …     

Characterization of a new dog isolate of canine distemper virus from China

Canine distemper virus (CDV) is a highly contagious pathogen of dogs. Vaccination is an effective way to protect dogs from CDV infection, but occasionally fails. In the present study, a wild type (wt) CDV, named XJ2, was isolated from a dead vaccinated dog. The hemagglutinin (H) gene of the XJ2 was amplified and analyzed for the molecular characteristics including N-glycosylation sites, phylogenesis, hydrophobicity and epitopes. The data indicated that XJ2 was a genetic variant strain of CDV. CDV-sero-negative dogs were inoculated intranasally with XJ2, developed severe clinical symptoms and died, suggesting high virulence.     

Molecular characterization of isolates of anagyris vein yellowing virus,plantago mottle virus and scrophularia mottle virus – comparison of various approaches for tymovirus classification

Summary. The complete nucleotide sequences were determined for the genomic RNAs of three tymoviruses, i.e. isolates of anagyris vein yellowing virus (AVYV), plantago mottle virus (PlMoV) and scrophularia mottle virus (SrMV) which are all serologically closely related to ononis yellow mosaic virus (ibid) and to Nemesia ring necrosis virus (NeRNV), a recently described recombinant virus which is widely spread in commercially grown ornamental plant species belonging to the Scrophulariaceae. Total nucleotide and coat protein amino acid sequence identities revealed similar groupings in the genus tymovirus as serological studies did. The latter, however, tended to suggest much closer relationships than the molecular data and may fail to recognise the distinctiveness of new tymovirus species. The usefulness of various species demarcation criteria for the classification of tymoviruses is discussed.     

Genetic characterization of Tribeč virus and Kemerovo virus, two tick-transmitted human-pathogenic Orbiviruses

We determined the complete genome sequences of Tribe? virus (TRBV) and Kemerovo virus (KEMV), two tick-transmitted Orbiviruses that can cause diseases of the central nervous system and that are currently classified into the Great Island virus serogroup. VP2 proteins of TRBV and KEMV show very low sequence similarity to the homologous VP4 protein of tick-transmitted Great Island virus (GIV). The new sequence data support previous serological classification of these Orbiviruses into the Kemerovo serogroup, which is different from the Great Island virus serogroup. Genome segment 9 of TRBV and KEMV encodes several overlapping ORF's in the +1 reading frame relative to VP6(Hel). A co-phylogenetic analysis indicates a host switch from insect-borne Orbiviruses toward Ixodes species, which is in disagreement with previously published data.     

Examination of a purified A′ influenza virus preparation by potentiometry

Summary The potentiometric titration of a purified influenza A virus preparation revealed 100.7×10^–4 M base and 68.8 × 10^–4 M acid-binding capacity per g. of virus protein N. The titration curve was characterized by the following fourpK values:pK ₁ = 3.37;pK ₂ = 4.50;pK ₃ = 6.37, andpK ₄ = 9.75. The isoionic point was at pH 5.43.Attempt was made to identify the dissociating groups and it was found that the carboxylic groups (pK ₁ andpK ₂) may either be glutamyl or aspartyl groups, while the cationic groups are probably the imidazolium of histidine (pK ₃) and the -amino residues of lysine (pK ₄).Inaotivation of the hemagglutinating activity of the virus preparation by mild treatment with formaldehyde at pH 8.0 resulted in a simultaneous disappearence of the -amino groups of lysine (pK ₄). The same treatment at pH 9.0 resulted in the loss of all the cationic groups previously demonstrable.The possible role of the stable positive charges on the surface of the virus at physiological pH is discussed from the point of view of the physico-chemistry of the hemagglutination.     

Complete nucleotide sequence of a Chinese isolate of Grapevine leafroll-associated virus 3 reveals a 5′ UTR of 802 nucleotides

Grapevine leafroll-associated virus 3 (GLRaV-3) is widely spread in China. Here we report, for the first time, the complete nucleotide sequence of the Chinese isolate (LN) of GLRaV-3. The 18,563-nt genomic RNA is the largest of the GLRaV-3 genomes reported to date, with a 5′ untranslated region of 802 nt. Its sequence shares 87.99–98.15 % identity with those of previously reported isolates, and phylogenetic analysis suggested placing isolate LN in group 3, together with another fully sequenced isolate, PL-20.     

Performances of NeuMoDx™, a random-access system for hepatitis B virus DNA and hepatitis C virus RNA quantification

ObjectiveMonitoring of viral loads (VL) for hepatitis B and C viruses (HBV; HCV) is essential to evaluate disease progression and treatment response. Automated, random-access rapid systems are becoming standard to provide clinicians with reliable VL. The aim of this study was to evaluate the analytical performances of the recently launched NeuMoDx™ for HBV-DNA and HCV-RNA quantification.MethodsClinical samples routinely quantified on the Beckman–Veris system were either retrospectively (frozen samples; HBV n = 178, HCV n = 249), or in parallel (fresh primary tubes; HBV n = 103, HCV n = 117) tested using NeuMoDx™. Linearity range was assessed on serial dilutions of high-titre plasmas containing different genotypes for HBV (A–E, n = 9) and HCV (1a,1b,2–5, n = 12).ResultsOverall test failure, mostly internal control amplification failure, was 2.3% and was not influenced by matrix types (fresh or frozen). For HBV VL, κ agreement was 74%, with 27 (12.6%) discrepancies. Correlation between HBV assays on 72 quantified samples by both methods was excellent (r = 0.963) with a mean bias (NeuMoDx™–Veris) of 0.21 log IU/mL. For HCV VL, κ agreement reached 94%, with 9 (2.8%) discrepancies. The r correlation factor between assays on 104 samples was 0.960 with a mean bias of –0.14 log IU/mL (NeuMoDx™–Veris). Serial dilutions confirmed the claimed linear ranges for all analysed HBV and HCV genotypes. The mean turnaround time was 72 minutes (range 55–101 minutes) for HBV and 96 minutes (range 78–133 minutes) for HCV.ConclusionResults obtained on the NeuMoDx™ confirmed the overall good functionality of the system with a short turn-around-time, full traceability and easy handling. These results on HBV and HCV VL look promising and should be challenged with further comparisons.     

Molecular and biological characterization of a Marek’s disease virus field strain with reticuloendotheliosis virus LTR insert

A Marek’s disease virus (MDV) field strain designated GX0101 was isolated from a layer flock and confirmed to be a recombinant virus with an insert of a long terminal repeat (LTR) from the reticuloendotheliosis virus (REV). A chimeric molecule containing an REV-LTR insert of 539 bp and its flanking sequences from MDV was amplified and sequenced. An REV-LTR downstream from the Internal Repeat Short (IRS) region has 77.4–98.6% homology to seven REV field strains isolated from different avian species in different parts of the world. The insertion site is located downstream of SORF 1 and upstream of SORF2 in the IRS region near the junction with the Unique Short (US) region in the MDV serotype 1 genome. Chicken experiments were conducted to determine the oncogenicity of the recombinant GX0101 virus and its transmissibility to contact chickens. Dot blot hybridization was used to detect the presence of the pp38 gene in feather tips from GX0101 or Md5 infected and contact birds. The pp38 was detected in GX0101 contact birds about 1–2 weeks earlier than in Md5 birds when both groups were vaccinated with HVT vaccine. Long term pathogenicity tests in specific pathogen free (SPF) chickens reveal that the recombinant GX0101 has a higher virulence than GA, but less virulence than Md5, the very virulent pathotype of MDV. This is the first report on an oncogenic serotype 1 MDV field strain with LTR insert and its pathogenicity.     

Complete nucleotide sequence of a new potexvirus, “Phaius virus X”, isolated from Phaius flavus Lindl.

A flexuous virus was isolated from cultivated Phaius flavus Lindl. plants in Japan with a latent infection. The virus was assigned to the genus Potexvirus based on morphology and analysis of its complete nucleotide sequence. The genome is 5,816 nucleotides in length, excluding the 3′-terminal poly (A) tail, and contains five open reading frames (ORFs), which is consistent with other members of the genus Potexvirus. The ORF nucleotide sequences differ from those of previously reported potexviruses, but the newly isolated virus is closely related to lily virus X and mint virus X. We propose that this virus should be designated as Phaius virus X (PhaVX).     

Detection of a new mumps virus genotype during parotitis epidemic of 2006-2007 in the state of São Paulo, Brazil

Nucleotide sequence analyses of the SH gene of 18 mumps virus isolates collected in the 2006–2007 parotitis epidemic in the state of São Paulo identified a new genotype, designated genotype M. This new designation fulfills all the parameters required to define a new mumps virus genotype. The parameters were established by an expert panel in collaboration with the World Health Organization (WHO) in 2005. This information will enhance the mumps virus surveillance program both at the national and global levels. J. Med. Virol. 80:323–329, 2008. © 2007 Wiley‐Liss, Inc.     

Seroprevalence distribution of Aichi virus among a French population in 2006–2007

Little is known about the epidemiology of Aichi virus, which is a new member of the family Picornaviridae, in the genus Kobuvirus. We report here on seroprevalence in France. Sera were screened using an enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G. Of 972 sera tested, seroprevalence ranged from 25% for the 7-month-to-9-year-old age group to about 85% for the 30-to-39-year-old age group and older age groups. Our ELISA correlated well with the microneutralization technique. This study shows that Aichi virus is quite frequent in France and that seroconversion occurs before the age of 40.     

Presence of a polyA tail at the 3�� end of maize rayado fino virus RNA

Maize rayado fino virus (MRFV) is distinct from other marafiviruses in that its genome reportedly lacks a poly(A) tail at the 3' terminus. We now show that the MRFV genome is indeed polyadenylated.