bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the cobas 4800 CT/NG Test with Culture for Detecting Neisseria gonorrhoeae in Genital and Nongenital Specimens in a Low-Prevalence Population in New Zealand
Authors: Bromhead Collette , Miller Amanda , Jones Mark , Whiley David 
Published: March 2013

ABSTRACT

To assess the clinical utility of replacing microbial culture for
Neisseria gonorrhoeae
with a nucleic acid amplification test (NAAT), we compared
N. gonorrhoeae
culture with the cobas 4800 CT/NG test for 18,247 urogenital and 666 nongenital samples. For urogenital specimens, the sensitivity, specificity, and positive and negative predictive values of the cobas
N. gonorrhoeae
PCR were 98.7%, 100%, 95.6%, and 100%, respectively, and for nongenital specimens, the values were 100%, 99.8%, 92.9%, and 100%, respectively. In our test population, 37% (10,185) of patients tested over the study period were screened for
C. trachomatis
by PCR but were not screened for gonorrhea by culture. Of these, 43 were
N. gonorrhoeae
positive by PCR and therefore went undiagnosed. The cobas 4800 CT/NG test diagnosed 33% (
n
= 30) more urogenital and 25% (
n
= 3) more rectal gonorrhea infections than culture and, based on the above performance indicators, does not require supplementary testing for urogenital or rectal specimens. The ability to test noninvasive specimens (such as urine and self-taken vulvovaginal swabs) for
N. gonorrhoeae
will enable more patients to be screened for infection, thus offering significant positive public health benefits.
Performance of the MagNA Pure 96 System for Cytomegalovirus Nucleic Acid Amplification Testing in Clinical Samples
Authors: Edelmann A. , Eichenlaub U. , Lepek S. , Krüger D. H. , Hofmann J. 
Published: March 2013

ABSTRACT
This report shows the performance of MagNA Pure 96 automated nucleic acid extraction for the quantitative detection of cytomegalovirus DNA in clinical samples by real-time PCR. The obtained results demonstrate that this workflow is characterized by high sensitivity and linearity and ensures reliable, reproducible clinical diagnostics.
At Low pH, Influenza Virus Matrix Protein M1 Undergoes a Conformational Change Prior to Dissociating from the Membrane
Authors: Fontana Juan , Steven Alasdair C. 
Published: March 2013

ABSTRACT
The M1 matrix protein of influenza A virus, which plays multiple roles in virion assembly and infection, underlies the viral envelope. However, previous studies have given differing accounts of the number of layers in the M1-envelope complex and their thicknesses and compositions. To resolve this issue, we performed cryo-electron microscopy and cryo-electron tomography on the self-same specimens. At neutral pH, there were two kinds of complexes, corresponding to a lipid bilayer with embedded glycoproteins, with and without a closely associated, 4-nm-thick sheet of M1 protein. The reported discrepancies arose from differences in imaging conditions, i.e., in defocus and in whole-particle projections versus thin tomographic slices. Exposure of virions to low pH (as in the endosome) promotes membrane fusion, and previous work has shown that the M2 ion channel causes the virion interior to acidify also. We found that after 5 min at pH 4.9, the proportion of virions lacking an M1 layer increased from 10% to 50%. In virions retaining an M1 layer under these conditions, the M1-envelope complex exhibited two states, viz, the original, neutral-pH state and one in which the M1 layer appeared thinner and/or closer to the membrane. These observations extend previous indications that acidic pH causes the M1 layer to dissociate, leaving the envelope more pliable and, consequently, fusion compatible, and they show that dissociation is preceded by a conformational change in M1.
The Hepatitis E Virus Capsid C-Terminal Region Is Essential for the Viral Life Cycle: Implication for Viral Genome Encapsidation and Particle Stabilization
Authors: Shiota Tomoyuki , Li Tian-Cheng , Yoshizaki Sayaka , Kato Takanobu , Wakita Takaji , Ishii Koji 
Published: March 2013

ABSTRACT
Although the C-terminal 52 amino acids (C52aa) of hepatitis E virus (HEV) capsid are not essential for morphology, the C52aa-encoding region is required for replication. Transfection of a C52aa knockdown mutant showed transient growth, and the earliest population included a majority of noninfectious (possibly empty) particles and a minority of infectious particles with C-terminal capsid degradation. Finally, the complete revertant was generated reproducibly. C52aa is essential for the viral life cycle, promoting accurate encapsidation and stabilizing encapsidated particles.
Ovine Fetal Immune Response to Cache Valley Virus Infection
Authors: Rodrigues Hoffmann Aline , Dorniak Piotr , Filant Justyna , Dunlap Kathrin A. , Bazer Fuller W. , de la Concha-Bermejillo Andres , Welsh Christabel Jane , Varner Patricia , Edwards John Francis 
Published: March 2013

ABSTRACTCache Valley virus (CVV)-induced malformations have been previously reproduced in ovine fetuses. To evaluate the development of the antiviral response by the early, infected fetus, before the development of immunocompetency, ovine fetuses at 35 days of gestation were inoculatedin uterowith CVV and euthanized at 7, 10, 14, 21, and 28 days postinfection. The antiviral immune response in immature fetuses infected with CVV was evaluated. Gene expression associated with an innate, immune response was quantified by real-time quantitative PCR. The upregulated genes in infected fetuses includedISG15,Mx1,Mx2,IL-1,IL-6,TNF-α,TLR-7, andTLR-8. The amount of Mx1 protein, an interferon-stimulated GTPase capable of restricting growth of bunyaviruses, was elevated in the allantoic and amniotic fluid in infected fetuses. ISG15 protein expression was significantly increased in target tissues of infected animals. B lymphocytes and immunoglobulin-positive cells were detected in lymphoid tissues and in the meninges of infected animals. These results demonstrated that the infected ovine fetus is able to initiate an innate and adaptive immune response much earlier than previously known, which presumably contributes to viral clearance in infected animals.
Reassortment of NS Segments Modifies Highly Pathogenic Avian Influenza Virus Interaction with Avian Hosts and Host Cells
Authors: Petersen Henning , Wang Zhongfang , Lenz Eva , Pleschka Stephan , Rautenschlein Silke 
Published: March 2013

ABSTRACT

Highly pathogenic avian influenza viruses (HPAIV) of subtypes H5 and H7 have caused numerous outbreaks in diverse poultry species and rising numbers of human infections. Both HPAIV subtypes support a growing concern of a pandemic outbreak, specifically via the avian-human link. Natural reassortment of both HPAIV subtypes is a possible event with unpredictable outcome for virulence and host specificity of the progeny virus for avian and mammalian species. NS reassortment of H5N1 HPAIV viruses in the background of A/FPV/Rostock/1934 (H7N1) HPAIV has been shown to change virus replication kinetics and host cell responses in mammalian cells. However, not much is known about the virus-host interaction of such viruses in avian species. In the present study, we show that the NS segment of A/Vietnam/1203/2004 (FPV NS VN, H5N1) HPAIV significantly altered the characteristics of the H7 prototype HPAIV in tracheal organ cultures (TOC) of chicken and turkey
in vitro
, with decreased replication efficiency accompanied by increased induction of type I interferon (IFN) and apoptosis. Furthermore, species-specific differences between chicken and turkey were demonstrated. Interestingly, NS-reassortant FPV NS VN showed an overall highly pathogenic phenotype, with increased virulence and replication potential compared to the wild-type virus after systemic infection of chicken and turkey embryos. Our data demonstrate that single reassortment of an H5-type NS into an H7-type HPAIV significantly changed virus replication abilities and influenced the avian host cell response without prior adaptation.
Regulation of Viral and Cellular Gene Expression by Kaposi's Sarcoma-Associated Herpesvirus Polyadenylated Nuclear RNA
Authors: Rossetto Cyprian C. , Tarrant-Elorza Margaret , Verma Subhash , Purushothaman Pravinkumar , Pari Gregory S. 
Published: March 2013

ABSTRACT

Kaposi's sarcoma-associated herpesvirus (KSHV) is the cause of Kaposi's sarcoma and body cavity lymphoma. In cell culture, KSHV results in a latent infection, and lytic reactivation is usually induced with the expression of K-Rta or by treatment with phorbol 12-myristate 13-acetate (TPA) and/or
n
-butyrate. Lytic infection is marked by the activation of the entire viral genomic transcription cascade and the production of infectious virus. KSHV-infected cells express a highly abundant, long, noncoding transcript referred to as polyadenylated nuclear RNA (PAN RNA). PAN RNA interacts with specific demethylases and physically binds to the KSHV genome to mediate activation of viral gene expression. A recombinant BACmid lacking the PAN RNA locus fails to express K-Rta and does not produce virus. We now show that the lack of PAN RNA expression results in the failure of the initiation of the entire KSHV transcription program. In addition to previous findings of an interaction with demethylases, we show that PAN RNA binds to protein components of Polycomb repression complex 2 (PRC2). RNA-Seq analysis using cell lines that express PAN RNA shows that transcription involving the expression of proteins involved in cell cycle, immune response, and inflammation is dysregulated. Expression of PAN RNA in various cell types results in an enhanced growth phenotype, higher cell densities, and increased survival compared to control cells. Also, PAN RNA expression mediates a decrease in the production of inflammatory cytokines. These data support a role for PAN RNA as a major global regulator of viral and cellular gene expression.
Adeno-Associated Virus-Mediated Gene Transfer Leads to Persistent Hepatitis B Virus Replication in Mice Expressing HLA-A2 and HLA-DR1 Molecules
Authors: Dion Sarah , Bourgine Maryline , Godon Ophélie , Levillayer Florence , Michel Marie-Louise 
Published: March 2013

ABSTRACT
Hepatitis B virus (HBV) persistence may be due to impaired HBV-specific immune responses being unable to eliminate efficiently or cure infected hepatocytes. The immune mechanisms that lead to HBV persistence have not been completely identified, and no appropriate animal model is available for such studies. Therefore, we established a chronic HBV infection model in a mouse strain with human leukocyte antigen A2/DR1 (HLA-A2/DR1) transgenes and an H-2 class I/class II knockout. The liver of these mice was transduced with adeno-associated virus serotype 2/8 (AAV2/8) carrying a replication-competent HBV DNA genome. In all AAV2/8-transduced mice, hepatitis B virus surface antigen, hepatitis B virus e antigen, and HBV DNA persisted in serum for at least 1 year. Viral replication intermediates and transcripts were detected in the livers of the AAV-injected mice. The hepatitis B core antigen was expressed in 60% of hepatocytes. No significant inflammation was observed in the liver. This was linked to a higher number of regulatory T cells in liver than in controls and a defect in HBV-specific functional T-cell responses. Despite the substantial tolerance resulting from expression of HBV antigens in hepatocytes, we succeeded in priming functional HBV-specific T-cell responses in peripheral tissues, which subsequently reached the liver. This AAV2/8-HBV-transduced HLA-A2/DR1 murine model recapitulates virological and immunological characteristics of chronic HBV infection, and it could be useful for the development of new treatments and immune-based therapies or therapeutic vaccines for chronic HBV infections.
Infection with 2009 H1N1 Influenza Virus Primes for Immunological Memory in Human Nose-Associated Lymphoid Tissue, Offering Cross-Reactive Immunity to H1N1 and Avian H5N1 Viruses
Authors: Mahallawi Waleed H. , Kasbekar Anand V. , McCormick Maxwell S. , Hoschler Katja , Temperton Nigel , Leong Samuel C. , Beer Helen , Ferrara Francesca , McNamara Paul S. , Zhang Qibo 
Published: March 2013

ABSTRACT
Influenza is a highly contagious mucosal infection in the respiratory tract. The 2009 pandemic H1N1 (pH1N1) influenza virus infection resulted in substantial morbidity and mortality in humans. Little is known on whether immunological memory develops following pH1N1 infection and whether it provides protection against other virus subtypes. An enzyme-linked immunosorbent spot assay was used to analyze hemagglutinin (HA)-specific memory B cell responses after virus antigen stimulation in nose-associated lymphoid tissues (NALT) from children and adults. Individuals with serological evidence of previous exposure to pH1N1 showed significant cross-reactive HA-specific memory B cell responses to pH1N1, seasonal H1N1 (sH1N1), and avian H5N1 (aH5N1) viruses upon pH1N1 virus stimulation. pH1N1 virus antigen elicited stronger cross-reactive memory B cell responses than sH1N1 virus. Intriguingly, aH5N1 virus also activated cross-reactive memory responses to sH1N1 and pH1N1 HAs in those who had previous pH1N1 exposure, and that correlated well with the memory response stimulated by pH1N1 virus antigen. These memory B cell responses resulted in cross-reactive neutralizing antibodies against sH1N1, 1918 H1N1, and aH5N1 viruses. The 2009 pH1N1 infection appeared to have primed human host with B cell memory in NALT that offers cross-protective mucosal immunity to not only H1N1 but also aH5N1 viruses. These findings may have important implications for future vaccination strategies against influenza. It will be important to induce and/or enhance such cross-protective mucosal memory B cells.
Post-traumatic intrahepatic splenosis mimicking a neuroendocrine tumour
Authors: Leong Chee Weng , Menon Tulsi , Rao Sudhakar 
Published: March 2013

A 52-year-old man presented with abdominal pain with a background of splenectomy 25 years previously. Initial investigations lead to suspicion of a neuroendocrine tumour. Positron emission tomography octreotide scanning and chromogranin were raised. He subsequently underwent a lateral segmentectomy. The histopathology was consistent with splenosis.1. Splenosis must be considered as differential in any patient with abdominal symptoms post-traumatic splenectomy.2. Positron emission tomography (PET) octreotide scanning can detect splenosis giving false positives for a neuroendocrine tumour. This is the first case to describe such an association.
Novel stretch-sensor technology allows quantification of adherence and quality of home-exercises: a validation study
Authors: Rathleff Michael Skovdal , Bandholm Thomas , Ahrendt Peter , Olesen Jens Lykkegaard , Thorborg Kristian 
Published: March 2013

ObjectiveTo investigate if a new stretch sensor attached to an elastic exercise band can assist health professionals in evaluating adherence to home exercises. More specifically, the study investigated whether health professionals can differentiate elastic band exercises performed as prescribed, from exercises not performed as prescribed.Methods10 participants performed four different shoulder-abduction exercises in two rounds (80 exercise scenarios in total). The scenarios were (1) low contraction speed, full range of motion (0–90°), (2) high contraction speed, full range of motion (0–90°), (3) low contraction speed, diminished range of motion (0–45°) and (4) unsystematic pull of the elastic exercise band. Stretch-sensor readings from each participant were recorded and presented randomly to the raters. Two raters were asked to differentiate between unsystematic pull (scenario 4), from shoulder abduction strength exercises (scenarios 1–3). The next two raters were asked to identify the four different exercise scenarios (scenarios 1–4).ResultsThe first two raters were able to differentiate between unsystematic pull (scenario 4) from shoulder abduction strength exercises (scenarios 1–3). They made no errors (100% success rate). The second two raters were both able to identify each of the 80 scenarios (scenarios 1–4). They too made no errors (100% success rate).ConclusionsThe stretch-sensor readings from the elastic exercise band allow health professionals to quantify whether strength-exercises have been performed as prescribed. These findings have great implications for future clinical practice and research where home exercises are the drugs-of-choice, as they enable clinicians and researchers to measure the exact adherence and quality of the prescribed exercises.
Meteorological factors and risk of community-acquired Legionnaires’ disease in Switzerland: an epidemiological study
Authors: Conza Lisa , Casati Simona , Limoni Costanzo , Gaia Valeria 
Published: March 2013

ObjectivesThe aim of this study was to identify meteorological factors that could be associated with an increased risk of community-acquired Legionnaires’ disease (LD) in two Swiss regions.DesignRetrospective epidemiological study using discriminant analysis and multivariable Poisson regression.SettingWe analysed legionellosis cases notified between January 2003 and December 2007 and we looked for a possible relationship between incidence rate and meteorological factors.ParticipantsCommunity-acquired LD cases in two Swiss regions, the Canton Ticino and the Basle region, with climatically different conditions were investigated.Primary outcome measuresVapour pressure, temperature, relative humidity, wind, precipitation and radiation recorded in weather stations of the two Swiss regions during the period January 2003 and December 2007.ResultsDiscriminant analysis showed that the two regions are characterised by different meteorological conditions. A multiple Poisson regression analysis identified region, temperature and vapour pressure during the month of infection as significant risk factors for legionellosis. The risk of developing LD was 129.5% (or 136.4% when considering vapour pressure instead of temperature in the model) higher in the Canton Ticino as compared to the Basle region. There was an increased relative risk of LD by 11.4% (95% CI 7.70% to 15.30%) for each 1 hPa rise of vapour pressure or by 6.7% (95% CI 4.22% to 9.22%) for 1°C increase of temperature.ConclusionsIn this study, higher water vapour pressure and heat were associated with a higher risk of community-acquired LD in two regions of Switzerland.
Low prevalence of methicillin-resistantStaphylococcus aureusamong men who have sex with men attending an STI clinic in Amsterdam: a cross-sectional study
Authors: Joore I K C W , van Rooijen Martijn Sebastiaan , Schim van der Loeff Maarten Franciscus , de Neeling A J , van Dam Alje , de Vries Henry J C 
Published: March 2013

ObjectiveCommunity-associated methicillin-resistantStaphylococcus aureus(CA-MRSA) is common among men who have sex with men (MSM) in the USA. It is unknown whether this is also the case in Amsterdam, the Netherlands.DesignCross-sectional study.SettingSexually transmitted infection outpatient low-threshold clinic, Amsterdam, the Netherlands.ParticipantsBetween October 2008 and April 2010, a total of 211 men were included, in two groups: (1) 74 MSM with clinical signs of a skin or soft tissue infection (symptomatic group) and (2) 137 MSM without clinical signs of such infections (asymptomatic group).Primary outcome measuresS aureusand MRSA infection and/or colonisation. Swabs were collected from the anterior nasal cavity, throat, perineum, penile glans and, if present, from infected skin lesions. Culture forS aureuswas carried out on blood agar plates and for MRSA on selective chromagar plates after enrichment in broth. If MRSA was found, the spa-gene was sequenced.Secondary outcome measuresAssociated demographic characteristics, medical history, risk factors for colonisation withS aureusand high-risk sexual behaviour were collected through a self-completed questionnaire.ResultsThe prevalence ofS aureuscolonisation in the nares was 37%, the pharynx 11%, the perianal region 12%, the glans penis 10% and in skin lesions 40%. In multivariable analysis adjusting for age, anogenitalS aureuscolonisation was significantly associated with the symptomatic group (p=0.01) and marginally with HIV (p=0.06). MRSA was diagnosed in two cases: prevalence 0.9% (95% CI 0.1% to 3.4%)). Neither had CA-MRSA strains.ConclusionsCA-MRSA among MSM in Amsterdam is rare. Genital colonisation ofS aureusis not associated with high-risk sexual behaviour.
Transvenous to arterial Onyx embolization
Authors: Albuquerque Felipe C , Ducruet Andrew F , Crowley R Webster , Bristol Ruth E , Ahmed Azam , McDougall Cameron G 
Published: March 2013

Background/objectiveTransarterial infusion of Onyx is now widely used in the treatment of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs). Transvenous Onyx embolization is rarely performed, and usually in cases of carotid cavernous fistulas. We describe a novel technique of transvenous Onyx embolization in the treatment of three high risk DAVFs and one vein of Galen (VOG) AVM.MethodsCases were evaluated with specific attention to technical caveats, clinical indications, and complications. Patients were treated during 2011–2012 by two operators (FCA and CGM). Standard transfemoral venous approaches were employed in order to obtain access into the draining venous system in all cases.ResultsFour female patients, aged 5 months to 68 years, were treated. Two patients, one presenting with headache and the other with a bruit, demonstrated high risk DAVFs involving the transverse–sigmoid sinuses. One patient, who was asymptomatic, manifested a high risk ethmoidal DAVF that was discovered incidentally during treatment of a basilar aneurysm. The final patient presented with symptoms of a pineal region mass and was found to have a VOG AVM. In all cases, a microcatheter was navigated through the draining venous pouch and into the ostium of an arterial feeder. A single Onyx infusion from this position filled multiple arterial feeders and resulted in cures in the first three patients and a significant reduction in AVM nidus in the fourth patient. No complications occurred.ConclusionsTransvenous Onyx infusion into a single arterial feeder can produce retrograde embolization of numerous other arterial feeders supplying high risk DAVFs and complex cerebral AVMs. This technique appears to be safe and potentially curative in select cases.