bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Wild-Type and Alternate Transcription Termination Signals in the Rift Valley Fever Virus Genome
Authors: Lara Estelle , Billecocq Agnès , Leger Psylvia , Bouloy Michèle 
Published: September 2011

ABSTRACT

Rift Valley fever (RVF) is a mosquito-borne zoonotic disease caused by a phlebovirus of the family
Bunyaviridae
, which affects humans and ruminants in Africa and the Middle East. RFV virus (RVFV) possesses a single-stranded tripartite RNA genome of negative/ambisense polarity. The S segment utilizes the ambisense strategy and codes for two proteins, the N nucleoprotein and the nonstructural NSs protein, in opposite orientations. The two open reading frames (ORFs) are separated by an intergenic region (IGR) highly conserved among strains and containing a motif, 5′-GCUGC-3′, present on the genome and antigenome, which was shown previously to play a role in transcription termination (C. G. Albarino, B. H. Bird, and S. T. Nichol, J. Virol. 81:5246-5256, 2007; T. Ikegami, S. Won, C. J. Peters, and S. Makino, J. Virol. 81:8421-8438, 2007). Here, we created recombinant RVFVs with mutations or deletions in the IGR and showed that the substitution of the motif sequence by a series of five A's inactivated transcription termination at the wild-type site but allowed the transcriptase to recognize another site with the consensus sequence present in the opposite ORF. Similar situations were observed for mutants in which the motif was still present in the IGR but located close to the stop codon of the translated ORF, supporting a model in which transcription is coupled to translation and translocating ribosomes abrogate transcription termination. Our data also showed that the signal tolerated some sequence variations, since mutation into 5′-GCAGC-3′ was functional, and 5′-GUAGC-3′ is likely the signal for the termination of the 3′ end of the L mRNA.
Vaccinia Virus L2 Protein Associates with the Endoplasmic Reticulum near the Growing Edge of Crescent Precursors of Immature Virions and Stabilizes a Subset of Viral Membrane Proteins
Authors: Maruri-Avidal Liliana , Weisberg Andrea S. , Moss Bernard 
Published: September 2011

ABSTRACT
The initial step in poxvirus morphogenesis, the formation of crescent membranes, occurs within cytoplasmic factories. L2 is one of several vaccinia virus proteins known to be necessary for formation of crescents and the only one synthesized early in infection. Virus replication was unaffected when the L2R open reading frame was replaced by L2R containing an N-terminal epitope tag while retaining the original promoter. L2 colocalized with the endoplasmic reticulum (ER) protein calnexin throughout the cytoplasm of infected and transfected cells. Topological studies indicated that the N terminus of L2 is exposed to the cytoplasm with the hydrophobic C terminus anchored in the ER. Using immunogold labeling and electron microscopy, L2 was detected in tubular membranes outside factories and inside factories near crescents and close to the edge or rim of crescents; a similar labeling pattern was found for the ER luminal protein disulfide isomerase (PDI). The phenotype of L2 conditional lethal mutants and the localization of L2 suggest that it participates in elongation of crescents by the addition of ER membrane to the growing edge. Small amounts of L2 and PDI were detected within immature and mature virions, perhaps trapped during assembly. The repression of L2, as well as A11 and A17, two other proteins that are required for viral crescent formation, profoundly decreased the stability of a subset of viral membrane proteins including those comprising the entry-fusion complex. To avoid degradation, these unstable membrane proteins may need to directly insert into the viral membrane or be rapidly shunted there from the ER.
Differential Reactivity of Germ Line Allelic Variants of a Broadly Neutralizing HIV-1 Antibody to a gp41 Fusion Intermediate Conformation
Authors: Alam S. Munir , Liao Hua-Xin , Dennison S. Moses , Jaeger Frederick , Parks Robert , Anasti Kara , Foulger Andrew , Donathan Michele , Lucas Judith , Verkoczy Laurent , Nicely Nathan , Tomaras Georgia D. , Kelsoe Garnett , Chen Bing , Kepler Thomas B. , Haynes Barton F. 
Published: September 2011

ABSTRACTGenetic factors, as well as antigenic stimuli, can influence antibody repertoire formation. Moreover, the affinity of antigen for unmutated naïve B cell receptors determines the threshold for activation of germinal center antibody responses. The gp41 2F5 broadly neutralizing antibody (bNAb) uses the VH2-5 gene, which has 10 distinct alleles that use either a heavy-chain complementarity-determining region 2 (HCDR2) aspartic acid (DH54) or an HCDR2 asparagine (NH54) residue. The 2F5 HCDR2 DH54residue has been shown to form a salt bridge with gp41665K; the VH2-5 germ line allele variant containing NH54cannot do so and thus should bind less avidly to gp41. Thus, the induction of 2F5 bNAb is dependent on both genetic and structural factors that could affect antigen affinity of unmutated naïve B cell receptors. Here, we studied allelic variants of the VH2-5 inferred germ line forms of the HIV-1 gp41 bNAb 2F5 for their antigen binding affinities to gp41 linear peptide and conformational protein antigens. Both VH2-5 2F5 inferred germ line variants bound to gp41 peptides and protein, including the fusion intermediate protein mimic, although more weakly than the mature 2F5 antibody. As predicted, the affinity of the NH54variant for fusion-intermediate conformation was an order of magnitude lower than that of the DH54VH2-5 germ line antibody, demonstrating that allelic variants of 2F5 germ line antibodies differentially bind to gp41. Thus, these data demonstrate a genetically determined trait that may affect host responses to HIV-1 envelope epitopes recognized by broadly neutralizing antibodies and has implications for unmutated ancestor-based immunogen design.
TRIM5α Does Not Affect Simian Immunodeficiency Virus SIV
mac251
Replication in Vaccinated or Unvaccinated Indian Rhesus Macaques following Intrarectal Challenge Exposure
Authors: Fenizia Claudio , Keele Brandon F. , Nichols David , Cornara Stefano , Binello Nicolò , Vaccari Monica , Pegu Poonam , Robert-Guroff Marjorie , Ma Zhong-Min , Miller Christopher J. , Venzon David , Hirsch Vanessa , Franchini Genoveffa 
Published: September 2011

ABSTRACT

TRIM5α is a natural resistance factor that binds retroviral capsid proteins and restricts virus replication. The B30.2/SPRY domain of TRIM5α is polymorphic in rhesus macaques, and some alleles are associated with reduced simian immunodeficiency virus (SIV) SIV
mac251
and SIV
smE543
replication
in vivo
. We determined the distribution of TRIM5α alleles by PCR and sequence analysis of the B30.2/SPRY domain in a cohort of 82 macaques. Thirty-nine of these macaques were mock vaccinated, 43 were vaccinated with either DNA-SIV/ALVAC-SIV/gp120, ALVAC-SIV/gp120, or gp120 alone, and all were exposed intrarectally to SIV
mac251
at one of three doses. We assessed whether the TRIM5α genotype of the macaques affected the replication of challenge virus by studying the number of SIV variants transmitted, the number of exposures required, the SIV
mac251
viral level in plasma and tissue, and the CD4
+
T-cell counts. Our results demonstrated that TRIM5α alleles, previously identified as restrictive for SIV
mac251
replication
in vivo
following intravenous exposure, did not affect SIV
mac251
replication following mucosal exposure, regardless of prior vaccination, challenge dose, or the presence of the protective major histocompatibility complex alleles (MamuA01
+
, MamuB08
+
, or MamuB017
+
). The TRIM5α genotype had no apparent effect on the number of transmitted variants or the number of challenge exposures necessary to infect the animals. DNA sequencing of the SIV
mac251
Gag gene of the two stocks used in our study revealed SIV
mac239
-like sequences that are predicted to be resistant to TRIM5α restriction. Thus, the TRIM5α genotype does not confound results of mucosal infection of rhesus macaques with SIV
mac251
.
HepG2 Cells Expressing MicroRNA miR-122 Support the Entire Hepatitis C Virus Life Cycle
Authors: Narbus Christopher M. , Israelow Benjamin , Sourisseau Marion , Michta Maria L. , Hopcraft Sharon E. , Zeiner Gusti M. , Evans Matthew J. 
Published: September 2011

ABSTRACT

The liver-specific microRNA miR-122 is required for efficient hepatitis C virus (HCV) RNA replication both in cell culture and
in vivo
. In addition, nonhepatic cells have been rendered more efficient at supporting this stage of the HCV life cycle by miR-122 expression. This study investigated how miR-122 influences HCV replication in the miR-122-deficient HepG2 cell line. Expression of this microRNA in HepG2 cells permitted efficient HCV RNA replication and infectious virion production. When a missing HCV receptor is also expressed, these cells efficiently support viral entry and thus the entire HCV life cycle.
The DBA.2 Mouse Is Susceptible to Disease following Infection with a Broad, but Limited, Range of Influenza A and B Viruses
Authors: Pica Natalie , Iyer Arun , Ramos Irene , Bouvier Nicole M. , Fernandez-Sesma Ana , García-Sastre Adolfo , Lowen Anice C. , Palese Peter , Steel John 
Published: September 2011

ABSTRACT

We assessed the relative susceptibilities to disease of the DBA.2 and C57BL/6 mouse models upon infection with a range of influenza A and B viruses. DBA.2 mice were more susceptible to disease upon inoculation with human H1N1 influenza A virus strains, several swine influenza viruses, and influenza B viruses but were not overtly susceptible to infection with human seasonal H3N2 strains. Hemagglutination inhibition and immunoglobulin isotype profiling indicated that DBA.2 and C57BL/6 mice generate comparable humoral responses upon equivalent 50% mouse lethal dose (MLD
50
) challenges with influenza virus. Our data demonstrate the utility of DBA.2 mice for the elucidation of influenza virus pathogenicity determinants and the testing of influenza vaccines.
Mutations in the Membrane-Proximal Region of the Influenza A Virus M2 Protein Cytoplasmic Tail Have Modest Effects on Virus Replication
Authors: Stewart Shaun M. , Pekosz Andrew 
Published: September 2011

ABSTRACT
Influenza A virus encodes M2, a proton channel that has been shown to be important during virus entry and assembly. In order to systematically investigate the role of the membrane-proximal residues in the M2 cytoplasmic tail in virus replication, we utilized scanning and directed alanine mutagenesis in combination with transcomplementation assays and recombinant viruses. The membrane-proximal residues 46 to 69 tolerated numerous mutations, with little, if any, effect on virus replication, suggesting that protein structure rather than individual amino acid identity in this region may be critical for M2 protein function.
015 Temporal trends in head injury outcomes from 2003 to 2010 in England and Wales, and the effect of specialist neurosciences care: a Cohort Study
Authors: Fuller G , Lecky F , Woodford M , Bouamra O , Jenks T , Coats T , Hutchinson P 
Published: September 2011

Objectives and BackgroundsHead injury (HI) is the leading cause of death in trauma, and case fatality rates after blunt HI did not improve in England and Wales between 1994 and 2003. Subsequent national guidelines have recommended that all severe HIs should be treated in neuroscience units (NSUs). The aim of this study was to investigate case fatality trends in HI since 2003 and establish the effect of specialist neuroscience care on mortality after severe HI.MethodsWe conducted a cohort study using prospectively recorded data from the TARN trauma registry for adult patients presenting with blunt trauma between 2003 and 2009. Temporal trends in log odds of death adjusted for case mix were examined for patients with and without HI. Rates of transfer and mortality were compared for patients with severe HI treated in NSUs vs non-specialist centres. Propensity score adjusted multivariate logistic regression was then used to calculate case mix adjusted odds of death associated with non-NSU care.ResultsSince 2003 there was an average 12% reduction in case mix adjusted log odds of death per annum in patients with HI (n=15 173), with a similar but smaller trend in non-HI trauma mortality (n=48 681). During the study period the proportion of patients with HI treated entirely in non-NSUs decreased from 31% to 19%, (p<0.01). Severe HI management in non-NSUs was associated with a 11% increase in crude mortality (p<0.01) and a case mix adjusted 1.85 (95% CI 1.57 to 2.19) fold increase in odds of death.ConclusionsThe reduction in log odds of death following HI since 2003 is consistent with increased levels of treatment in NSUs, or better management following the introduction of national HI guidelines. Our data suggests that increasing transfer rates to NSUs represents an important strategy in further improving outcomes in severe HI.
018 One-year prognosis after syncope and the failure of the ROSE decision instrument to predict 1-year adverse events: Abstract 018 Figure 1
Authors: Henderson S S , Reed M J , Newby D E , Gray A J 
Published: September 2011

Objectives and Backgrounds(1) To investigate the incidence of adverse events at 1-year in the cohort of Emergency Department (ED) syncope patients enrolled in the original ROSE study; (2) To investigate the time to adverse event; and (3) To investigate the test performance of the ROSE decision instrument to detect events at 1-year.MethodsThis report details the 1-year follow-up of adult syncope patients presenting to the ED who were enrolled into the ROSE study, a single centre, prospective, observational cohort study. The primary end point was the combination of serious outcome (SO) and all-cause death (ACD) at 1 year. SO encompassed acute myocardial infarction, life-threatening arrhythmia, need for pacemaker/implantable defibrillator, pulmonary embolus, cerebrovascular accident, intracranial or subarachnoid haemorrhage, interventional procedure or haemorrhage requiring blood transfusion. Secondary endpoints were ACD and cardiovascular SO at 1 year.Results1043 patients were available for analysis; 162 patients (15.5%) had a primary outcome. 28 (17%) of these were within 24 h, 56 (35%) were within 1 week and 77 (48%) were within 1 month. The remaining 85 (52%) outcomes occurred between months 2 and 12. At 1 year, 71 (6.8%) patients had died and 76 (7.3%) had a cardiovascular SO. The sensitivity and specificity of the ROSE decision instrument for 1-year SO and ACD was 71.6% (63.9–78.3) and 71.1% (67.9–74.0), for 1-year ACD was 76.1% (64.2–85.1) and 67.4% (64.3–70.3) and for 1-year cardiovascular SO was 75.0% (63.5–83.9) and 67.5% (64.5–70.5).ConclusionsThe proportion of patients with SO and ACD 1 year after syncope is similar to recent international syncope studies. We have defined the proportion of patients with cardiovascular SO at 1-year, and have shown that most events occurred in the first month with decreased frequency of events noted after that time frame especially marked for cardiovascular SO. More than 50% of the outcomes observed however occurred after the first month. The ROSE decision instrument does not perform well at predicting 1-year outcome of ED syncope patients.Abstract 018 Figure 1Kaplan–Meier survival curve showing 1-year combined SO and ACD, 1-year ACD, 1-year CVS SO and 1-year combined SO and ACD for ROSE positive and ROSE negative patients.
002 Special delivery: where best to take a head injured patient?
Authors: Pickering A , Cooper K , Harnan S , Sutton A 
Published: September 2011

Objectives and BackgroundsThe current focus on development of specialist centres in the UK to improve outcomes is based on evidence from overseas care models. While care in a specialist neurosurgical centre will improve outcomes for head injured patients, does transferring them directly have any clinical benefit compared with delivery to a local hospital for initial stabilisation and subsequent transfer to the specialist centre? We performed a systematic review to identify the clinical effectiveness of bypassing local hospital care in moderate or severely head injured patients.MethodsRelevant studies were identified by an electronic search of key databases. Papers in English were included if they compared the outcomes of moderate or severely head injured patients (GCS<13, AIS≥3) directly transferred and treated at a specialist centre (SC) vs those who received their initial resuscitation at a local hospital (LH) with some or all patients later transferred to a SC. Outcomes were assessed using available mortality and morbidity data.ResultsWe identified 6 studies involving 2580 patients. One further study was found that did not report the number of subjects. Most studies used SC registry data and adjusted their outcomes for age, pupil dilatation and injury severity. No studies included results for, or adjusted for, patients not transferred after delivery to the LH. For mortality, the adjusted OR was taken from three studies. For those taken to their LH first the OR of death was higher than for the direct transfer group (SC). The level of significance was marginal and undergoing formal meta-analysis at the time of submission. The adjustment of data tended to favour direct transfer over local hospital delivery. No significant difference was reported for morbidity outcomes (Glasgow Outcome Scale) in the three studies that looked at these.ConclusionsThe reviewed literature comparing direct transfer of head injured patients to specialist neurosurgical centres vs initial local hospital delivery is sparse. What evidence there is supports direct transfer to improve mortality although, at present, this is only marginally significant.
022 Methoxyflurane: would giving the “Green Whistle” the green light benefit mountain casualties in Snowdonia?
Authors: Burgess S , Dykes L 
Published: September 2011

Objectives and BackgroundsMethoxyflurane, currently licensed only in Australasia, is a convenient, rapidly effective pre-hospital analgesic, although it achieves inferior pain reduction compared to intravenous morphine or intranasal fentanyl. Methoxyflurane in analgesic doses causes only minor, rapidly-reversible initial side effects, but repeated exposure can cause irreversible dose-dependent nephrotoxicity which limits duration of administration. In addition, there are occupational health concerns for personnel working in confined spaces. There are methoxyflurane proponents within the UK mountain medicine community, and we wondered whether methoxyflurane would be suitable for use by Mountain Rescue Team first-aiders treating casualties in Snowdonia if it became available in the UK.MethodsOur Mountain Medicine database (all casualties brought to Bangor ED following mountain incidents resulting in contact with Mountain Rescue Teams and/or RAF Search & rescue helicopter) was interrogated to determine how many trauma casualties could have been treated with methoxyflurane based upon the current Australasian product license indications/contraindications for the Penthox inhaler.ResultsFrom 651 mountain casualties (January 2004–December 2010) sufficient data were available in 593 cases to identify 429 trauma casualties, 329 (77%) of which could theoretically have been treated with methoxyflurane. This was almost identical to those eligible to receive Entonox (76%). However, many cases would have required methoxyflurane for longer than the maximum 1-h because of prolonged scene/evacuation times in mountain settings.ConclusionsThe maximum duration of methoxyflurane administration would be insufficient as the primary analgesic in many Snowdonia mountain casualties, however, the use of methoxyflurane as a holding measure while I/N diamorphine is being prepared may be a viable option. Mountain casualties are often treated in tent-like rescue shelters and enclosed helicopter fuselages, which may endanger rescuer health if methoxyflurane were used without adequate ventilation. Further work is required to elucidate how frequently low ambient temperature precludes the use of Entonox.
027 Paediatric emergency department attendances between 2000 and 2009: trends in a large UK Children's Hospital
Authors: Lai J , Mason S , Burke D , Julious S A , Freeman J V 
Published: September 2011

Objectives and BackgroundThere has been an increase in UK demand for emergency department services. This may be attributed to changes in public behaviour or the availability of out of hours services. The objective of this study is to investigate whether these changes are reflected in paediatric cases by identifying patterns in paediatric emergency department attendances (ED) from a large UK urban hospital.MethodsData relating to admissions and ED contacts were obtained from a large UK Children's hospital from 01 January 2000 to 31 December 2009. Cases were categorised as trauma if the diagnosis text inferred physical (penetrating or blunt) injury. Graphical investigation was undertaken of the mean monthly daily counts of trauma/non-trauma contacts.ResultsThere were a total of 455 990 contacts made to ED. Of this figure, 46.9% were categorised as trauma overall. There has been a profound increase in hospital admissions from ED (+47.14%), admissions overall (+40.11%) and total ED attendances (+27.11%) throughout this time period. Observing trends for trauma attendances, there was a slight decrease (−11.72%) while for non-trauma attendances, there was a severe increase (+76.71%) in the annual number of attendances. Trends for the average year indicate that for trauma attendances compared to the annual mean, the largest increase and decrease is observed in December (+21.09%) and August (−27.19%) respectively. For non-trauma attendances, the largest increase and decrease is observed in June (+22.48%) and December (−30.97%) respectively.ConclusionThere has been an increase in paediatric emergency department attendances from 2000 to 2009. However, the increase is mainly attributed to conditions categorised as non-trauma rather than trauma. Annual patterns exhibit seasonal variation. In addition, admissions rates from ED from have increased by 47%. Further investigation is required to understand reasons for the rising demand in emergency department services and specifically, the increase in non-trauma attendances and admissions.