bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of a Commercial SD Dengue Virus NS1 Antigen Capture Enzyme-Linked Immunosorbent Assay Kit for Early Diagnosis of Dengue Virus Infection
Authors: Wang Seok Mui , Sekaran Shamala Devi 
Published: June 2010

ABSTRACT
Early definitive diagnosis of dengue virus infection may help in the timely management of dengue virus infection. We evaluated the Standard Diagnostics (SD, South Korea) dengue virus nonstructural protein NS1 antigen enzyme-linked immunosorbent assay (SD dengue NS1 Ag ELISA) for the detection of dengue virus NS1 antigen in patients' sera, using a total of 399 serum samples in a comparison with real-time reverse transcription (RT)-PCR, an in-house IgM capture (MAC)-ELISA, and a hemagglutination inhibition (HI) assay. Of the 320 dengue sera, 205 (64%) tested positive for NS1 antigen compared to 300 (93.75%) by either MAC-ELISA or RT-PCR, 161 (50.31%) by RT-PCR, and 226 (70.36%) by MAC-ELISA only. The assay was able to detect NS1 antigen in convalescent-phase sera until day 14 of infection. The NS1 detection rate is inversely proportional while the IgM detection rate is directly proportional to the presence of IgG antibodies. The overall sensitivity and specificity of the SD dengue NS1 Ag ELISA in the detection of “confirmed dengue virus” sera are 76.76% and 98.31%, respectively. This suggests that the SD kit is highly specific and sensitive for the detection of NS1 antigen. However, caution is needed when the kit is used as a single assay, as detection in samples that contained the virus was only about 81.97%. Combining this assay with an IgM and/or IgG assay will increase the sensitivity of detection, especially in areas with a higher prevalence of secondary dengue virus infections.
Activation of the Interferon Response by Human Cytomegalovirus Occurs via Cytoplasmic Double-Stranded DNA but Not Glycoprotein B
Authors: DeFilippis Victor R. , Sali Tina , Alvarado David , White Laura , Bresnahan Wade , Früh Klaus J. 
Published: June 2010

ABSTRACT

In vitro
infection of cells with the betaherpesvirus human cytomegalovirus (HCMV) stimulates an innate immune response characterized by phosphorylation of the transcription factor interferon regulatory factor 3 (IRF3) and subsequent expression of IRF3-dependent genes. While previous work suggests that HCMV envelope glycoprotein B is responsible for initiating this reaction, the signaling pathways stimulated by virus infection that lead to IRF3 phosphorylation have largely been uncharacterized. Recently, we identified Z DNA binding protein 1 (ZBP1), a sensor of cytoplasmic DNA, as an essential protein for this response. We now describe a human fibroblast cell line exhibiting a recessive defect that results in the absence of activation of IRF3 following treatment with HCMV but not Sendai virus or double-stranded RNA. In addition, we show that while exposure of these cells to soluble HCMV glycoprotein B is capable of triggering IRF3-dependent gene transcription, transfection of the cells with double-stranded DNA is not. Furthermore, we show that overexpression of ZBP1 in these cells reestablishes their ability to secrete interferon in response to HCMV and that multiple ZBP1 transcriptional variants exist in both wild-type and mutant cells. These results have two major implications for the understanding of innate immune stimulation by HCMV. First, they demonstrate that HCMV glycoprotein B is not the essential molecular pattern that induces an IRF3-dependent innate immune response. Second, IRF3-terminal signaling triggered by HCMV particles closely resembles that which is activated by cytoplasmic double-stranded DNA.
Elevated Cyclic AMP Levels in T Lymphocytes Transformed by Human T-Cell Lymphotropic Virus Type 1
Authors: Kress Andrea K. , Schneider Grit , Pichler Klemens , Kalmer Martina , Fleckenstein Bernhard , Grassmann Ralph 
Published: June 2010

ABSTRACTHuman T-cell lymphotropic virus type 1 (HTLV-1), the cause of adult T-cell leukemia/lymphoma (ATLL), transforms CD4+T cells to permanent growth through its transactivator Tax. HTLV-1-transformed cells share phenotypic properties with memory and regulatory T cells (T-reg). Murine T-reg-mediated suppression employs elevated cyclic AMP (cAMP) levels as a key regulator. This led us to determine cAMP levels in HTLV-1-transformed cells. We found elevated cAMP concentrations as a consistent feature of all HTLV-1-transformed cell lines, includingin vitro-HTLV-1-transformed, Tax-transformed, and patient-derived cells. In transformed cells with conditional Tax expression, high cAMP levels coincided with the presence of Tax but were lost without it. However, transient ectopic expression of Tax alone was not sufficient to induce cAMP. We found specific downregulation of the cAMP-degrading phosphodiesterase 3B (PDE3B) in HTLV-1-transformed cells, which was independent of Tax in transient expression experiments. This is in line with the notion that PDE3B transcripts and cAMP levels are inversely correlated. Overexpression of PDE3B led to a decrease of cAMP in HTLV-1-transformed cells. Decreased expression of PDE3B was associated with inhibitory histone modifications at the PDE3B promoter and the PDE3B locus. In summary, Tax transformation and its continuous expression contribute to elevated cAMP levels, which may be regulated through PDE3B suppression. This shows that HTLV-1-transformed cells assume biological features of long-lived T-cell populations that potentially contribute to viral persistence.
Replacement of the Replication Factors of Porcine Circovirus (PCV) Type 2 with Those of PCV Type 1 Greatly Enhances Viral Replication
I
n
V
itro
Authors: Beach N. M. , Juhan N. M. , Cordoba L. , Meng X. J. 
Published: June 2010

ABSTRACT

Porcine circovirus type 1 (PCV1), originally isolated as a contaminant of PK-15 cells, is nonpathogenic, whereas porcine circovirus type 2 (PCV2) causes an economically important disease in pigs. To determine the factors affecting virus replication, we constructed chimeric viruses by swapping open reading frame 1 (ORF1) (
rep
) or the origin of replication (Ori) between PCV1 and PCV2 and compared the replication efficiencies of the chimeric viruses in PK-15 cells. The results showed that the replication factors of PCV1 and PCV2 are fully exchangeable and, most importantly, that both the Ori and
rep
of PCV1 enhance the virus replication efficiencies of the chimeric viruses with the PCV2 backbone.
Modeling Adenovirus Latency in Human Lymphocyte Cell Lines
Authors: Zhang Yange , Huang Wen , Ornelles David A. , Gooding Linda R. 
Published: June 2010

ABSTRACT
Species C adenovirus establishes a latent infection in lymphocytes of the tonsils and adenoids. To understand how this lytic virus is maintained in these cells, four human lymphocytic cell lines that support the entire virus life cycle were examined. The T-cell line Jurkat ceased proliferation and died shortly after virus infection. BJAB, Ramos (B cells), and KE37 (T cells) continued to divide at nearly normal rates while replicating the virus genome. Viral genome numbers peaked and then declined in BJAB cells below one genome per cell at 130 to 150 days postinfection. Ramos and KE37 cells maintained the virus genome at over 100 copies per cell over a comparable period of time. BJAB cells maintained the viral DNA as a monomeric episome. All three persistently infected cells lost expression of the cell surface coxsackie and adenovirus receptor (CAR) within 24 h postinfection, and CAR expression remained low for at least 340 days postinfection. CAR loss proceeded via a two-stage process. First, an initial loss of cell surface staining for CAR required virus late gene expression and a CAR-binding fiber protein even while CAR protein and mRNA levels remained high. Second, CAR mRNA disappeared at around 30 days postinfection and remained low even after virus DNA was lost from the cells. At late times postinfection (day 180), BJAB cells could not be reinfected with adenovirus, even when CAR was reintroduced to the cells via retroviral transduction, suggesting that the expression of multiple genes had been stably altered in these cells following infection.
Alpha Interferon and Not Gamma Interferon Inhibits Salmonid Alphavirus Subtype 3 Replication
In Vitro
Authors: Xu Cheng , Guo Tz-Chun , Mutoloki Stephen , Haugland Øyvind , Marjara Inderjit S. , Evensen Øystein 
Published: June 2010

ABSTRACT

Salmonid alphavirus (SAV) is an emerging virus in salmonid aquaculture, with SAV-3 being the only subtype found in Norway. Until now, there has been little focus on the alpha interferon (IFN-α)-induced antiviral responses during virus infection
in vivo
or
in vitro
in fish. The possible involvement of IFN-γ in the response to SAV-3 is also not known. In this study, the two IFNs were cloned and expressed as recombinant proteins (recombinant IFN-α [rIFN-α] and rIFN-γ) and used for
in vitro
studies. SAV-3 infection in a permissive salmon cell line (TO cells) results in IFN-α and IFN-stimulated gene (ISG) mRNA upregulation. Preinfection treatment (4 to 24 h prior to infection) with salmon rIFN-α induces an antiviral state that inhibits the replication of SAV-3 and protects the cells against virus-induced cytopathic effects (CPE). The antiviral state coincides with a strong expression of Mx and ISG15 mRNA and Mx protein expression. When rIFN-α is administered at the time of infection and up to 24 h postinfection, virus replication is not inhibited, and cells are not protected against virus-induced CPE. By 40 h postinfection, the alpha subunit of eukaryotic initiation factor 2 (eIF2α) is phosphorylated concomitant with the expression of the E2 protein as assessed by Western blotting. Postinfection treatment with rIFN-α results in a moderate reduction in E2 expression levels in accordance with a moderate downregulation of cellular protein synthesis, an approximately 65% reduction by 60 h postinfection. rIFN-γ has only a minor inhibitory effect on SAV-3 replication
in vitro
. SAV-3 is sensitive to the preinfection antiviral state induced by rIFN-α, while postinfection antiviral responses or postinfection treatment with rIFN-α is not able to limit viral replication.
Predictors of race-day jockey falls in flat racing in Australia
Authors: Hitchens Peta Lee , Blizzard Christopher Leigh , Jones Graeme , Day Lesley , Fell James 
Published: June 2010

ObjectivesRiding thoroughbred racehorses is a hazardous occupation. In this study, we investigated risk factors associated with falls by licensed thoroughbred racing jockeys participating in flat races conducted in Australia.MethodsData on race-day falls were extracted from stewards' reports. Denominator data were provided by Racing Information Services Australia on races conducted in Australia from August 2002 until July 2006. Incidence rate ratios (IRRs) were estimated using Poisson regression. Analyses were stratified by race grade (maiden, class, open/restricted).ResultsIn multivariable analyses, factors associated with falls were female sex of jockey (IRR 1.11; 95% CI 1.00 to 1.23), being an apprentice jockey (IRR 1.51; 95% CI 1.39 to 1.63), being an amateur jockey (IRR 1.44; 95% CI 1.11 to 1.86), drier tracks (p<0.001), younger horse age (p<0.001), shorter race distance (p<0.001), lower field size (p=0.013) and lower race grade (p<0.001). The IRRs for five factors associated with falls differed by category of race grade: those for apprentice jockey (interaction p=0.003), higher prize money (interaction p<0.001) and shorter race distance (interaction p=0.041) were greater in lower race grades, while those for fewer previous rides this meeting (interaction p=0.027) and drier track rating (interaction p=0.035) were greater in higher race grades. Female jockeys had a significantly higher incidence of falls when riding horses under 4 years of age in open and restricted races (interaction p=0.038), and the effects of lower field size in maiden races, and of shorter races, were more pronounced for falls occurring before the race.ConclusionsWe identified a range of factors associated with falls to thoroughbred racing jockeys riding in flat races that adds to the evidence base for formulating strategies to improve occupational health and safety standards in the thoroughbred racing industry.
How valid is a short measure of effort–reward imbalance at work? A replication study from Sweden
Authors: Leineweber Constanze , Wege Natalia , Westerlund Hugo , Theorell Töres , Wahrendorf Morten , Siegrist Johannes 
Published: June 2010

ObjectivesThere is an urgent need for validated measures of health-adverse psychosocial work environments. We tested the validity of a newly developed short version of the original questionnaire measuring effort–reward imbalance at work (ERI).MethodsThe study sample comprised working men and women (n=4771) participating in the Swedish Longitudinal Occupational Survey of Health (SLOSH), a nationally representative longitudinal cohort study, in 2006 and 2008. Structural equation modelling was applied to test factorial validity, using the ERI scales. Furthermore, criterion validity was explored with two prospectively assessed health indicators, poor self-reported health and depressive symptoms. Results are based on logistic and linear regression analyses, with appropriate confounder control.ResultsThe short version of the ERI questionnaire (16 items) provides satisfactory psychometric properties (internal consistency of scales, confirmatory factor analysis with a good model fit of the data with the theoretical structure). All scales, and the effort–reward ratio, were prospectively associated with an increased risk of poor general self-rated health and depressive symptoms, indicating satisfactory criterion validity.ConclusionThis short version of the ERI questionnaire provides a psychometrically useful tool for epidemiological studies focused on the health-adverse effects of work and employment in the context of a globalised economy.
Calculation of the benchmark duration of shift work associated with the development of impaired glucose metabolism: a 14-year cohort study on 7104 male workers
Authors: Suwazono Yasushi , Uetani Mirei , Oishi Mitsuhiro , Tanaka Kumihiko , Morimoto Hideki , Sakata Kouichi 
Published: June 2010

ObjectivesThe aim of this study was to calculate the benchmark doses (BMD) and their 95% lower confidence boundary (BMDL) for the threshold number of years of shift work associated with a relative increase in haemoglobin A1c (HbA1c), an index of glucose metabolism.MethodsA 14-year prospective cohort study was conducted in male workers at a Japanese steel company (n=7104) who had received annual health check-ups between 1991 and 2005. The endpoints were either a 10%, 15%, 20%, 25% or 30% increase in HbA1clevels during the observation period, compared to HbA1cat entry to the study. The associations between years of shift work and increases in HbA1cwere investigated using pooled logistic regression, adjusted for age, body mass index, mean arterial pressure, total serum cholesterol, creatinine, alanine aminotransferase, γ-glutamyl transpeptidase, uric acid, drinking habits, smoking habits and habitual exercise.ResultsThe BMDL/BMD for years of shift work were calculated using benchmark responses (BMRs) of 5% or 10% and parameters for duration of shift work and other covariates. Assuming a mean age of 53 years in workers aged 50 years or older, the BMDL/BMD for years of shift work with a BMR of 5% were 17.8/23.9 (≥15%), 15.7/18.7 (≥20%), 18.9/22.7 (≥25%) and 25.2/31.7 (≥30%). With a BMR of 10%, the respective values were 29.5/39.7 (≥15%), 24.3/28.9 (≥20%), 27.3/32.7 (≥25%) and 34.1/42.9 (≥30%).ConclusionThese results suggest that special attention should be paid to middle-aged workers whose years of shift work exceeds these threshold times.
HIGH-ENERGY EMISSION AND ABSORPTION IN CYGNUS X-1
Authors: DEL VALLE M. V. , ORELLANA M. , ROMERO G. E. 
Published: June 2010

The high-mass microquasar Cygnus X-1 has been detected during a flaring state at very high energies, E > 200 GeV . The observation was performed by the Atmospheric Cherenkov Telescope MAGIC. It constitutes the first experimental evidence of very-high energy (VHE) emission produced by a Galactic stellar-mass black hole. The observed signal was detected in coincidence with an X–ray flare. The gamma-ray flare occurred when the compact object was located behind the companion star with respect to the line of sight (superior conjunction of the compact object). In this configuration the absorption of VHE photons by annihilation with the stellar photons is expected to be maximum. This suggests that the emission has been originated far above the compact object. The energy spectrum is well fitted by a relatively soft power-law. We present a model for the absorption and the emission of VHE gamma-rays in Cyg X-1. Detailed calculations of the gamma-ray opacity due to pair creation are provided and used to establish constraints on the emitting region. We propose that the high energy flare was the result of the interaction between the jet and a very dense clump from the stellar wind.
NONTHERMAL RADIATION FROM CYGNUS X-1 CORONA
Authors: VIEYRO FLORENCIA L. , ROMERO GUSTAVO E. , VILA GABRIELA S. 
Published: June 2010

Cygnus X-1 was the first X–ray source widely accepted to be a black hole candidate, and remains among the most studied astronomical objects in its class. The detection of nonthermal radio, hard X–rays and gamma-rays reveals the fact that this kind of objects are capable of accelerating particles up to very high energies. In order to explain the electromagnetic emission from Cygnus X-1 in the low-hard state we present a model of a black hole corona with both relativistic lepton and hadron content. We characterize the corona as a two-temperature hot plasma plus a mixed nonthermal population in which energetic particles interact with magnetic, photon and matter fields. Our calculations include the radiation emitted by secondary particles (pions, muons and electron–positron pairs). Finally, we take into account the effects of photon absorption. We compare the results obtained from our model with data of Cygnus X-1 obtained by the COMPTEL instrument.
Prospects of the WSR-88D Radar for Cloud Studies
Authors: Melnikov Valery M. , Zrnić Dusan S. , Doviak Richard J. , Chilson Phillip B. , Mechem David B. , Kogan Yefim L. 
Published: June 2010

AbstractSounding of nonprecipitating clouds with the 10-cm wavelength Weather Surveillance Radar-1988 Doppler (WSR-88D) is discussed. Readily available enhancements to signal processing and volume coverage patterns of the WSR-88D allow observations of a variety of clouds with reflectivities as low as −25 dBZ (at a range of 10 km). The high sensitivity of the WSR-88D, its wide velocity and unambiguous range intervals, and the absence of attenuation allow accurate measurements of the reflectivity factor, Doppler velocity, and spectrum width fields in clouds to ranges of about 50 km. Fields of polarimetric variables in clouds, observed with a research polarimetric WSR-88D, demonstrate an abundance of information and help to resolve Bragg and particulate scatter. The scanning, Doppler, and polarimetric capabilities of the WSR-88D allow real-time, three-dimensional mapping of cloud processes, such as transformations of hydrometeors between liquid and ice phases. The presence of ice particles is revealed by high differential reflectivities and the lack of correlation between reflectivity and differential reflectivity in clouds in contrast to that found for rain. Pockets of high differential reflectivities are frequently observed in clouds; maximal values of differential reflectivity exceed 8 dB, far above the level observed in rain. The establishment of the WSR-88D network consisting of 157 polarimetric radars can be used to collect cloud data at any radar site, making the network a potentially powerful tool for climatic studies.
A Simple Technique for Creating Regional Composites of Sea Surface Temperature from MODIS for Use in Operational Mesoscale NWP
Authors: Knievel Jason C. , Rife Daran L. , Grim Joseph A. , Hahmann Andrea N. , Hacker Joshua P. , Ge Ming , Fisher Henry H. 
Published: June 2010

Abstract
This paper describes a simple technique for creating regional, high-resolution, daytime and nighttime composites of sea surface temperature (SST) for use in operational numerical weather prediction (NWP). The composites are based on observations from NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) aboard Aqua and Terra. The data used typically are available nearly in real time, are applicable anywhere on the globe, and are capable of roughly representing the diurnal cycle in SST. The composites’ resolution is much higher than that of many other standard SST products used for operational NWP, including the low- and high-resolution Real-Time Global (RTG) analyses. The difference in resolution is key because several studies have shown that highly resolved SSTs are important for driving the air–sea interactions that shape patterns of static stability, vertical and horizontal wind shear, and divergence in the planetary boundary layer. The MODIS-based composites are compared to in situ observations from buoys and other platforms operated by the National Data Buoy Center (NDBC) off the coasts of New England, the mid-Atlantic, and Florida. Mean differences, mean absolute differences, and root-mean-square differences between the composites and the NDBC observations are all within tenths of a degree of those calculated between RTG analyses and the NDBC observations. This is true whether or not one accounts for the mean offset between the skin temperatures of the MODIS dataset and the bulk temperatures of the NDBC observations and RTG analyses. Near the coast, the MODIS-based composites tend to agree more with NDBC observations than do the RTG analyses. The opposite is true away from the coast. All of these differences in point-wise comparisons among the SST datasets are small compared to the ±1.0°C accuracy of the NDBC SST sensors. Because skin-temperature variations from land to water so strongly affect the development and life cycle of the sea breeze, this phenomenon was chosen for demonstrating the use of the MODIS-based composite in an NWP model. A simulated sea breeze in the vicinity of New York City and Long Island shows a small, net, but far from universal improvement when MODIS-based composites are used in place of RTG analyses. The timing of the sea breeze’s arrival is more accurate at some stations, and the near-surface temperature, wind, and humidity within the breeze are more realistic.