bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical Evaluation of the FilmArray Blood Culture Identification Panel in Identification of Bacteria and Yeasts from Positive Blood Culture Bottles
Authors: Altun Osman , Almuhayawi Mohammed , Ullberg Måns , Özenci Volkan 
Published: October 2013

ABSTRACT
The FilmArray platform (FA; BioFire, Salt Lake City, UT) is a closed diagnostic system allowing high-order multiplex PCR analysis with automated readout of results directly from positive blood cultures in 1 h. In the present study, we evaluated the clinical performance of the FilmArray blood culture identification (BCID) panel, which includes 19 bacteria, five yeasts, and three antibiotic resistance genes. In total, 206 blood culture bottles were included in the study. The FilmArray could identify microorganisms in 153/167 (91.6%) samples with monomicrobial growth. Thirteen of the 167 (7.8%) microorganisms were not covered by the FilmArray BCID panel. In 6/167 (3.6%) samples, the FilmArray detected an additional microorganism compared to blood culture. When polymicrobial growth was analyzed, the FilmArray could detect all target microorganisms in 17/24 (71%) samples. Twelve blood culture bottles that yielded a positive signal but showed no growth were also negative by FilmArray. In 3/206 (1.5%) bottles, the FilmArray results were invalid. The results of the FilmArray were reproducible, as demonstrated by the testing and retesting of five bottles in the same day and a longitudinal follow-up of five other blood cultures up to 4 weeks. The present study shows that the FilmArray is a rapid identification method with high performance in direct identification of bacteria and yeasts from positive blood culture bottles.
External Quality Assessment for Avian Influenza A (H7N9) Virus Detection Using Armored RNA
Authors: Sun Yu , Jia Tingting , Sun Yanli , Han Yanxi , Wang Lunan , Zhang Rui , Zhang Kuo , Lin Guigao , Xie Jiehong , Li Jinming 
Published: October 2013

ABSTRACT

An external quality assessment (EQA) program for the molecular detection of avian influenza A (H7N9) virus was implemented by the National Center for Clinical Laboratories (NCCL) of China in June 2013. Virus-like particles (VLPs) that contained full-length RNA sequences of the hemagglutinin (HA), neuraminidase (NA), matrix protein (MP), and nucleoprotein (NP) genes from the H7N9 virus (armored RNAs) were constructed. The EQA panel, comprising 6 samples with different concentrations of armored RNAs positive for H7N9 viruses and four H7N9-negative samples (including one sample positive for only the MP gene of the H7N9 virus), was distributed to 79 laboratories in China that carry out the molecular detection of H7N9 viruses. The overall performances of the data sets were classified according to the results for the H7 and N9 genes. Consequently, we received 80 data sets (one participating group provided two sets of results) which were generated using commercial (
n
= 60) or in-house (
n
= 17) reverse transcription-quantitative PCR (qRT-PCR) kits and a commercial assay that employed isothermal amplification method (
n
= 3). The results revealed that the majority (82.5%) of the data sets correctly identified the H7N9 virus, while 17.5% of the data sets needed improvements in their diagnostic capabilities. These “improvable” data sets were derived mostly from false-negative results for the N9 gene at relatively low concentrations. The false-negative rate was 5.6%, and the false-positive rate was 0.6%. In addition, we observed varied diagnostic capabilities between the different commercially available kits and the in-house-developed assays, with the assay manufactured by BioPerfectus Technologies (Jiangsu, China) performing better than the others. Overall, the majority of laboratories have reliable diagnostic capacities for the detection of H7N9 virus.
Irreproducible and Uninterpretable Polymyxin B MICs for Enterobacter cloacae and Enterobacter aerogenes
Authors: Landman David , Salamera Julius , Quale John 
Published: October 2013

ABSTRACT

Carbapenem-resistant
Enterobacter
species are emerging nosocomial pathogens. As with most multidrug-resistant Gram-negative pathogens, the polymyxins are often the only therapeutic option. In this study involving clinical isolates of
E. cloacae
and
E. aerogenes
, susceptibility testing methods with polymyxin B were analyzed. All isolates underwent testing by the broth microdilution (in duplicate) and agar dilution (in duplicate) methods, and select isolates were examined by the Etest method. Selected isolates were also examined for heteroresistance by population analysis profiling. Using a susceptibility breakpoint of ≤2 μg/ml, categorical agreement by all four dilution tests (two broth microdilution and two agar dilution) was achieved in only 76/114 (67%) of
E. cloacae
isolates (65 susceptible, 11 resistant). Thirty-eight (33%) had either conflicting or uninterpretable results (multiple skip wells, i.e., wells that exhibit no growth although growth does occur at higher concentrations). Of the 11 consistently resistant isolates, five had susceptible MICs as determined by Etest. Heteroresistant subpopulations were detected in eight of eight isolates tested, with greater percentages in isolates with uninterpretable MICs. For
E. aerogenes
, categorical agreement between the four dilution tests was obtained in 48/56 (86%), with conflicting and/or uninterpretable results in 8/56 (14%). For polymyxin susceptibility testing of
Enterobacter
species, close attention must be paid to the presence of multiple skip wells, leading to uninterpretable results. Susceptibility also should not be assumed based on the results of a single test. Until the clinical relevance of skip wells is defined, interpretation of polymyxin susceptibility tests for
Enterobacter
species should be undertaken with extreme caution.
Qualitative Analysis To Ascertain Genotypic Identity of or Differences between Mycobacterium tuberculosis Isolates in Laboratories with Limited Resources
Authors: Sislema-Egas Fernanda , Ruiz-Serrano María Jesús , Bouza Emilio , García-de-Viedma Darío 
Published: October 2013

ABSTRACT

Mycobacterium tuberculosis
is currently genotyped using mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) typing, although the high cost of this technique restricts its implementation in resource-limited settings. We designed a MIRU-VNTR format, MLP3 (MIRU-VNTR length polymorphism triplex), that is based on the qualitative comparison of 5 nonfluorescent 3-band fingerprints in conventional electrophoresis and minimizes costs and technical demands. MLP3 successfully resolved cross-contamination alerts, discriminated reinfections from reactivations, clarified suspected microepidemics, and tracked transmission events of high epidemiological interest.
Detection of Canine Pneumovirus in Dogs with Canine Infectious Respiratory Disease
Authors: Mitchell Judy A. , Cardwell Jacqueline M. , Renshaw Randall W. , Dubovi Edward J. , Brownlie Joe 
Published: October 2013

ABSTRACTCanine pneumovirus (CnPnV) was recently identified during a retrospective survey of kenneled dogs in the United States. In this study, archived samples from pet and kenneled dogs in the United Kingdom were screened for CnPnV to explore the relationship between exposure to CnPnV and the development of canine infectious respiratory disease (CIRD). Within the pet dog population, CnPnV-seropositive dogs were detected throughout the United Kingdom and Republic of Ireland, with an overall estimated seroprevalence of 50% (n= 314/625 dogs). In the kennel population, there was a significant increase in seroprevalence, from 26% (n= 56/215 dogs) on the day of entry to 93.5% (n= 201/215 dogs) after 21 days (P<0001). Dogs that were seronegative on entry but seroconverted while in the kennel were 4 times more likely to develop severe respiratory disease than those that did not seroconvert (P< 0.001), and dogs with preexisting antibodies to CnPnV on the day of entry were significantly less likely to develop respiratory disease than immunologically naive dogs (P< 0.001). CnPnV was detected in the tracheal tissues of 29/205 kenneled dogs. Detection was most frequent in dogs with mild to moderate respiratory signs and histopathological changes and in dogs housed for 8 to 14 days, which coincided with a significant increase in the risk of developing respiratory disease compared to the risk of those housed 1 to 7 days (P< 0.001). These findings demonstrate that CnPnV is present in the United Kingdom dog population; there is a strong association between exposure to CnPnV and CIRD in the kennel studied and a potential benefit in vaccinating against CnPnV as part of a wider disease prevention strategy.
Characterization of Hepatitis C Virus Intra- and Intergenotypic Chimeras Reveals a Role of the Glycoproteins in Virus Envelopment
Authors: Steinmann Eike , Doerrbecker Juliane , Friesland Martina , Riebesehl Nina , Ginkel Corinne , Hillung Julia , Gentzsch Juliane , Lauber Chris , Brown Richard , Frentzen Anne , Pietschmann Thomas 
Published: October 2013

ABSTRACT
Hepatitis C virus (HCV) is highly variable and associated with chronic liver disease. Viral isolates are grouped into seven genotypes (GTs). Accumulating evidence indicates that viral determinants in the core to NS2 proteins modulate the efficiency of virus production. However, the role of the glycoproteins E1 and E2 in this process is currently poorly defined. Therefore, we constructed chimeric viral genomes to explore the role of E1 and E2 in HCV assembly. Comparison of the kinetics and efficiency of particle production by intragenotypic chimeras highlighted core and p7 as crucial determinants for efficient virion release. Glycoprotein sequences, however, had only a minimal impact on this process. In contrast, in the context of intergenotypic HCV chimeras, HCV assembly was profoundly influenced by glycoprotein genes. On the one hand, insertion of GT1a-derived (H77) E1-E2 sequences into a chimeric GT2a virus (Jc1) strongly suppressed virus production. On the other hand, replacement of H77 glycoproteins within the GT1a-GT2a chimeric genome H77/C3 by GT2a-derived (Jc1) E1-E2 increased infectious particle production. Thus, within intergenotypic chimeras, glycoprotein features strongly modulate virus production. Replacement of Jc1 glycoprotein genes by H77-derived E1-E2 did not grossly affect subcellular localization of core, E2, and NS2. However, it caused an accumulation of nonenveloped core protein and increased abundance of nonenveloped core protein structures with slow sedimentation. These findings reveal an important role for the HCV glycoproteins E1 and E2 in membrane envelopment, which likely depends on a genotype-specific interplay with additional viral factors.
The DNA Virus White Spot Syndrome Virus Uses an Internal Ribosome Entry Site for Translation of the Highly Expressed Nonstructural Protein ICP35
Authors: Kang Shih-Ting , Wang Han-Ching , Yang Yi-Ting , Kou Guang-Hsiung , Lo Chu-Fang 
Published: October 2013

ABSTRACT

Although shrimp white spot syndrome virus (WSSV) is a large double-stranded DNA virus (∼300 kbp), it expresses many polycistronic mRNAs that are likely to use internal ribosome entry site (IRES) elements for translation. A polycistronic mRNA encodes the gene of the highly expressed nonstructural protein ICP35, and here we use a dual-luciferase assay to demonstrate that this protein is translated cap independently by an IRES element located in the 5′ untranslated region of
icp35
. A deletion analysis of this region showed that IRES activity was due to stem-loops VII and VIII. A promoterless assay, a reverse transcription-PCR together with quantitative real-time PCR analysis, and a stable stem-loop insertion upstream of the
Renilla
luciferase open reading frame were used, respectively, to rule out the possibility that cryptic promoter activity, abnormal splicing, or read-through was contributing to the IRES activity. In addition, a Northern blot analysis was used to confirm that only a single bicistronic mRNA was expressed. The importance of ICP35 to viral replication was demonstrated in a double-stranded RNA (dsRNA) interference knockdown experiment in which the mortality of the
icp35
dsRNA group was significantly reduced. Tunicamycin was used to show that the α subunit of eukaryotic initiation factor 2 is required for
icp35
IRES activity. We also found that the intercalating drug quinacrine significantly inhibited
icp35
IRES activity
in vitro
and reduced the mortality rate and viral copy number in WSSV-challenged shrimp. Lastly, in Sf9 insect cells, we found that knockdown of the gene for the
Spodoptera frugiperda
40S ribosomal protein RPS10 decreased
icp35
IRES-regulated firefly luciferase activity but had no effect on cap-dependent translation.
Respiratory Syncytial Virus G Protein CX3C Motif Impairs Human Airway Epithelial and Immune Cell Responses
Authors: Chirkova Tatiana , Boyoglu-Barnum Seyhan , Gaston Kelsey A. , Malik Fahad M. , Trau Steven P. , Oomens Antonius G. P. , Anderson Larry J. 
Published: October 2013

ABSTRACTRespiratory syncytial virus (RSV) is a major cause of severe lower respiratory infection in infants and young children and causes disease in the elderly and persons with compromised cardiac, pulmonary, or immune systems. Despite the high morbidity rates of RSV infection, no highly effective treatment or vaccine is yet available. The RSV G protein is an important contributor to the disease process. A conserved CX3C chemokine-like motif in G likely contributes to the pathogenesis of disease. Through this motif, G protein binds to CX3CR1 present on various immune cells and affects immune responses to RSV, as has been shown in the mouse model of RSV infection. However, very little is known of the role of RSV CX3C-CX3CR1 interactions in human disease. In this study, we use anin vitromodel of human RSV infection comprised of human peripheral blood mononuclear cells (PBMCs) separated by a permeable membrane from human airway epithelial cells (A549) infected with RSV with either an intact CX3C motif (CX3C) or a mutated motif (CX4C). We show that the CX4C virus induces higher levels of type I/III interferon (IFN) in A549 cells, increased IFN-α and tumor necrosis factor alpha (TNF-α) production by human plasmacytoid dendritic cells (pDCs) and monocytes, and increased IFN-γ production in effector/memory T cell subpopulations. Treatment of CX3C virus-infected cells with the F(ab′)2form of an anti-G monoclonal antibody (MAb) that blocks binding to CX3CR1 gave results similar to those with the CX4C virus. Our data suggest that the RSV G protein CX3C motif impairs innate and adaptive human immune responses and may be important to vaccine and antiviral drug development.
Spherical Influenza Viruses Have a Fitness Advantage in Embryonated Eggs, while Filament-Producing Strains Are Selected
In Vivo
Authors: Seladi-Schulman Jill , Steel John , Lowen Anice C. 
Published: October 2013

ABSTRACT
Influenza viruses can take on two distinct morphologies: filamentous or spherical. While the functional significance of each virion type is unclear, filaments are generally observed in low-passage-number isolates, while an exclusively spherical morphology is seen in strains grown extensively in laboratory substrates. Previous studies have shown that filamentous morphology is lost upon passage in eggs. The fact that the filamentous morphology is maintained in nature but not in the laboratory suggests that filaments provide an advantage in the host that is not necessary for growth in laboratory substrates. To test this hypothesis and identify naturally occurring mutations that alter morphology, we examined the effect of serial adaptation in eggs, MDCK cells, and guinea pigs. Two filamentous strains, A/Netherlands/602/2009 (H1N1) and A/Georgia/M5081/2012 (H1N1), were passaged in eggs and MDCK cells. Conversely, the spherical laboratory strain A/Puerto Rico/8/1934 (H1N1) was passaged in guinea pigs. We found that although passage in eggs and MDCK cells can lead to a loss of filaments, an exclusively spherical morphology is not required for highly efficient growth in either substrate. We did, however, identify two point mutations in the matrix of egg passage 10 isolates that confer spherical morphology and increased growth in eggs. In contrast, serial passage in guinea pigs resulted in the selection of filament-forming variants. Sequencing revealed point mutations to the PR8 matrix that, when introduced individually, yielded filaments. These findings suggest a functional role for filaments in the infected host and expand the breadth of mutations known to affect influenza virus shape.
Cyclophilin A Binds to the Viral RNA and Replication Proteins, Resulting in Inhibition of Tombusviral Replicase Assembly
Authors: Kovalev Nikolay , Nagy Peter D. 
Published: October 2013

ABSTRACT

Replication of plus-stranded RNA viruses is greatly affected by numerous host-encoded proteins that act as restriction factors. Cyclophilins, which are a large family of cellular prolyl isomerases, have been found to inhibit Tomato bushy stunt tombusvirus (TBSV) replication in a
Saccharomyces cerevisiae
model based on genome-wide screens and global proteomics approaches. In this report, we further characterize single-domain cyclophilins, including the mammalian cyclophilin A and plant Roc1 and Roc2, which are orthologs of the yeast Cpr1p cyclophilin, a known inhibitor of TBSV replication in yeast. We found that recombinant CypA, Roc1, and Roc2 strongly inhibited TBSV replication in a cell-free replication assay. Additional
in vitro
studies revealed that CypA, Roc1, and Roc2 cyclophilins bound to the viral replication proteins, and CypA and Roc1 also bound to the viral RNA. These interactions led to inhibition of viral RNA recruitment, the assembly of the viral replicase complex, and viral RNA synthesis. A catalytically inactive mutant of CypA was also able to inhibit TBSV replication
in vitro
due to binding to the replication proteins and the viral RNA. Overexpression of CypA and its mutant in yeast or plant leaves led to inhibition of tombusvirus replication, confirming that CypA is a restriction factor for TBSV. Overall, the current work has revealed a regulatory role for the cytosolic single-domain Cpr1-like cyclophilins in RNA virus replication.
Epizootic Hemorrhagic Disease Virus Induces and Benefits from Cell Stress, Autophagy, and Apoptosis
Authors: Shai Ben , Schmukler Eran , Yaniv Roy , Ziv Naomi , Horn Galit , Bumbarov Velizar , Yadin Hagai , Smorodinsky Nechama I. , Bacharach Eran , Pinkas-Kramarski Ronit , Ehrlich Marcelo 
Published: October 2013

ABSTRACT
The mode and timing of virally induced cell death hold the potential of regulating viral yield, viral transmission, and the severity of virally induced disease. Orbiviruses such as the epizootic hemorrhagic disease virus (EHDV) are nonenveloped and cytolytic. To date, the death of cells infected with EHDV, the signal transduction pathways involved in this process, and the consequence of their inhibition have yet to be characterized. Here, we report that the Ibaraki strain of EHDV2 (EHDV2-IBA) induces apoptosis, autophagy, a decrease in cellular protein synthesis, the activation of c-Jun N-terminal kinase (JNK), and the phosphorylation of the JNK substrate c-Jun. The production of infectious virions decreased upon inhibition of apoptosis with the pan-caspase inhibitor Q-VD-OPH (quinolyl-valyl-O-methylaspartyl-[-2,6-difluorophenoxy]-methyl ketone), upon inhibition of autophagy with 3-methyladenine or via the knockout of the autophagy regulator Atg5, or upon treatment of infected cells with the JNK inhibitor SP600125 or the cyclin-dependent kinase (CDK) inhibitor roscovitine, which also inhibited c-Jun phosphorylation. Moreover, Q-VD-OPH, SP600125, and roscovitine partially reduced EHDV2-IBA-induced cell death, and roscovitine diminished the induction of autophagy by EHDV2-IBA. Taken together, our results imply that EHDV induces and benefits from the activation of signaling pathways involved in cell stress and death.
The
ha72
Core Gene of Baculovirus Is Essential for Budded Virus Production and Occlusion-Derived Virus Embedding, and Amino Acid K22 Plays an Important Role in Its Function
Authors: Huang Huachao , Wang Manli , Deng Fei , Hou Dianhai , Arif Basil M. , Wang Hualin , Hu Zhihong 
Published: October 2013

ABSTRACT

ha72
of
Helicoverpa armigera
nucleopolyhedrovirus (a homologue of
ac78
) was identified as a conserved late baculovirus gene and characterized. HA72 localizes in the intranuclear ring zone. By generating mutants, we showed that HA72 is essential for budded virus (BD) production and occlusion-derived virus (ODV) embedding. HA72 also interacted with P33, a baculoviral sulfhydryl oxidase. A point mutation of amino acid 22 from lysine to glutamic acid curtailed BV production and precluded ODV occlusion as well as interaction with P33.
Two Overlapping Regions within the N-Terminal Half of the Herpes Simplex Virus 1 E3 Ubiquitin Ligase ICP0 Facilitate the Degradation and Dissociation of PML and Dissociation of Sp100 from ND10
Authors: Perusina Lanfranca Mirna , Mostafa Heba H. , Davido David J. 
Published: October 2013

ABSTRACT
Herpes simplex virus 1 (HSV-1) establishes a lifelong latent infection in sensory neurons and can reactivate from latency under stress conditions. To promote lytic infection, the virus must interact with specific cellular factors to evade the host's antiviral defenses. The HSV-1 E3 ubiquitin ligase, infected cell protein 0 (ICP0), activates transcription of viral genes, in part, by mediating the degradation of certain cellular proteins that play a role in host antiviral mechanisms. One component of the cellular defenses that ICP0 disrupts is the suborganelle, nuclear domain 10 (ND10), by inducing the degradation and dissociation of the major organizer of ND10, a promyelocytic leukemia (PML) and ND10 constituent, Sp100. Because previously identified domains in ICP0 explain only partially how it directs the degradation and dissociation of PML and Sp100, we hypothesized that additional regions within ICP0 may contribute to these activities, which in turn facilitate efficient viral replication. To test this hypothesis, we used a series of ICP0 truncation mutants and examined PML protein levels and PML and Sp100 immunofluorescence staining in human embryonic lung cells. Our results demonstrate that two overlapping regions within the central N-terminal portion of ICP0 (residues 212 to 311) promoted the dissociation and degradation of PML and dissociation of Sp100 (residues 212 to 427). In conclusion, we have identified two additional regions in ICP0 involved in altering ND10 antiviral defenses in a cell culture model of HSV-1 infection.