bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Cytomegalovirus Exploits Interferon-Induced Transmembrane Proteins To Facilitate Morphogenesis of the Virion Assembly Compartment
Authors: Xie Maorong , Xuan Baoqin , Shan Jiaoyu , Pan Deng , Sun Yamei , Shan Zhao , Zhang Jinping , Yu Dong , Li Bin , Qian Zhikang
Published: January 2015

Recently, interferon-induced transmembrane proteins (IFITMs) have been identified to be key effector molecules in the host type I interferon defense system. The invasion of host cells by a large range of RNA viruses is inhibited by IFITMs during the entry step. However, the roles of IFITMs in DNA virus infections have not been studied in detail. In this study, we report that human cytomegalovirus (HCMV), a large human DNA virus, exploits IFITMs to facilitate the formation of the virion assembly compartment (vAC) during infection of human fibroblasts. We found that IFITMs were expressed constitutively in human embryonic lung fibroblasts (MRC5 cells). HCMV infection inhibited IFITM protein accumulation in the later stages of infection. Overexpression of an IFITM protein in MRC5 cells slightly enhanced HCMV production and knockdown of IFITMs by RNA interference reduced the virus titer by about 100-fold on day 8 postinfection, according to the findings of a virus yield assay at a low multiplicity of infection. Virus gene expression and DNA synthesis were not affected, but the typical round structure of the vAC was not formed after the suppression of IFITMs, thereby resulting in defective virion assembly and the production of less infectious virion particles. Interestingly, the replication of herpes simplex virus, a human herpesvirus that is closely related to HCMV, was not affected by the suppression of IFITMs in MRC5 cells. These results indicate that IFITMs are involved in a specific pathway required for HCMV replication.

IMPORTANCE
HCMV is known to repurpose the interferon-stimulated genes (ISGs) viperin and tetherin to facilitate its replication. Our results expand the range of ISGs that can be exploited by HCMV for its replication. This is also the first report of a proviral function of IFITMs in DNA virus replication. In addition, whereas previous studies showed that IFITMs modulate virus entry, which is a very early stage in the virus life cycle, we identified a new function of IFITMs during the very late stage of virus replication, i.e., virion assembly. Virus entry and assembly both involve vesicle transport and membrane fusion; thus, a common biochemical activity of IFITMs is likely to be involved. Therefore, our findings may provide a new platform for dissecting the molecular mechanism of action of IFITMs during the blocking or enhancement of virus infection, which are under intense investigation in this field.
Reverse Genetics System for Severe Fever with Thrombocytopenia Syndrome Virus
Authors: Brennan Benjamin , Li Ping , Zhang Shuo , Li Aqian , Liang Mifang , Li Dexin , Elliott Richard M.
Published: January 2015

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne pathogen that was first reported in China in 2009. Phylogenetic analysis of the viral genome showed that
SFTS virus
represents a new lineage within the
Phlebovirus
genus, distinct from the existing sandfly fever and Uukuniemi virus groups, in the family
Bunyaviridae
. SFTS disease is characterized by gastrointestinal symptoms, chills, joint pain, myalgia, thrombocytopenia, leukocytopenia, and some hemorrhagic manifestations with a case fatality rate of about 2 to 15%. Here we report the development of reverse genetics systems to study STFSV replication and pathogenesis. We developed and optimized functional T7 polymerase-based M- and S-segment minigenome assays, which revealed errors in the published terminal sequences of the S segment of the Hubei 29 strain of SFTSV. We then generated recombinant viruses from cloned cDNAs prepared to the antigenomic RNAs both of the minimally passaged virus (HB29) and of a cell culture-adapted strain designated HB29pp. The growth properties, pattern of viral protein synthesis, and subcellular localization of viral N and NSs proteins of wild-type HB29pp (wtHB29pp) and recombinant HB29pp viruses were indistinguishable. We also show that the viruses fail to shut off host cell polypeptide production. The robust reverse genetics system described will be a valuable tool for the design of therapeutics and the development of killed and attenuated vaccines against this important emerging pathogen.

IMPORTANCE
SFTSV and related tick-borne phleboviruses such as Heartland virus are emerging viruses shown to cause severe disease in humans in the Far East and the United States, respectively. Study of these novel pathogens would be facilitated by technology to manipulate these viruses in a laboratory setting using reverse genetics. Here, we report the generation of infectious SFTSV from cDNA clones and demonstrate that the behavior of recombinant viruses is similar to that of the wild type. This advance will allow for further dissection of the roles of each of the viral proteins in the context of virus infection, as well as help in the development of antiviral drugs and protective vaccines.
Analysis of the Functional Interchange between the IE1 and pp71 Proteins of Human Cytomegalovirus and ICP0 of Herpes Simplex Virus 1
Authors: Lu Yongxu , Everett Roger D.
Published: January 2015

Human cytomegalovirus (HCMV) immediate early protein IE1 and the tegument protein pp71 are required for efficient infection. These proteins have some functional similarities with herpes simplex virus 1 (HSV-1) immediate early protein ICP0, which stimulates lytic HSV-1 infection and derepresses quiescent HSV-1 genomes. All three proteins counteract antiviral restriction mediated by one or more components of promyelocytic leukemia (PML) nuclear bodies, and IE1 and pp71, acting together, almost completely complement ICP0 null mutant HSV-1. Here, we investigated whether ICP0 might substitute for IE1 or pp71 during HCMV infection. Using human fibroblasts that express ICP0, IE1, or pp71 in an inducible manner, we found that ICP0 stimulated replication of both wild-type (wt) and pp71 mutant HCMV while IE1 increased wt HCMV plaque formation and completely complemented the IE1 mutant. Although ICP0 stimulated IE2 expression from IE1 mutant HCMV and increased the number of IE2-positive cells, it could not compensate for IE1 in full lytic replication. These results are consistent with previous evidence that both IE1 and IE2 are required for efficient HCMV gene expression, but they also imply that IE2 functionality is influenced specifically by IE1, either directly or indirectly, and that IE1 may include sequences that have HCMV-specific functions. We discovered a mutant form of IE1 (YL2) that fails to stimulate HCMV infection while retaining 30 to 80% of the activity of the wt protein in complementing ICP0 null mutant HSV-1. It is intriguing that the YL2 mutation is situated in the region of IE1 that is shared with IE2 and which is highly conserved among primate cytomegaloviruses.

IMPORTANCE
Herpesvirus gene expression can be repressed by cellular restriction factors, one group of which is associated with structures known as ND10 or PML nuclear bodies (PML NBs). Regulatory proteins of several herpesviruses interfere with PML NB-mediated repression, and in some cases their activities are transferrable between different viruses. For example, the requirement for ICP0 during herpes simplex virus 1 (HSV-1) infection can be largely replaced by ICP0-related proteins expressed by other alphaherpesviruses and even by a combination of the unrelated IE1 and pp71 proteins of human cytomegalovirus (HCMV). Here, we report that ICP0 stimulates gene expression and replication of wt HCMV but cannot replace the need for IE1 during infection by IE1-defective HCMV mutants. Therefore, IE1 includes HCMV-specific functions that cannot be replaced by ICP0.
Paediatric multiple sclerosis: a qualitative study of families’ diagnosis experiences
Authors: Hinton Denise , Kirk Susan
Published: January 2015

Objective

To examine children's and parents’ experiences of obtaining a diagnosis of paediatric multiple sclerosis (MS) and identify potential facilitators and barriers to early diagnosis.

Design

Qualitative, semi-structured interviews conducted face-to-face in home settings with 31 parents and 21 children and adolescents (8–17 years old) with a clinical diagnosis of MS. Participants were recruited from 16 NHS Trusts and four MS voluntary organisations in the UK. Interviews were recorded and transcribed verbatim and analysed using the constant comparative method.

Results

Time to diagnosis ranged from 1 to 96 months (median 11.5, mean 23.3, SD 27.3). The findings suggest that delayed presentation to healthcare services, generalists’ assumptions about the nature of reported symptoms, lack of awareness of paediatric MS and delayed referral to specialists in paediatric MS were barriers to early investigation and accurate diagnosis. Children, adolescents and parents felt that their concerns about the child's health were not always taken seriously during medical consultations and that clinicians could be reluctant to diagnose MS in childhood. This created additional uncertainty about the child's condition and long-term prognosis.

Conclusions

Obtaining a diagnosis of paediatric MS can be a challenging and lengthy process with potentially adverse implications for the health of children/adolescents. Valuing families’ knowledge and experience of their child's health, performing a thorough medical examination early in the disease course and organising prompt referrals may aid the early investigation and diagnosis of this disease. In view of the diagnostic challenges, children/adolescents with suspected MS would benefit from early referrals to specialists in paediatric MS.
Comparison of an automated rapid plasma reagin (RPR) test with the conventional RPR card test in syphilis testing
Authors: Lee Jong-Han , Lim Chae Seung , Lee Min-Geol , Kim Hyon-Suk
Published: January 2015

Objective

We compared the automated non-treponemal reagin (rapid plasma reagin (RPR)) test with the conventional RPR card test for usefulness in clinical applications.

Setting

A comparative study of laboratory methods using clinical specimens in a single institute.

Participants

A total of 112 serum samples including 59Treponema pallidumparticle agglutination (TPPA)-positive and 53 TPPA-negative specimens were evaluated.

Outcome measures

HiSens Auto RPR LTIA (HBI, Anyang, Korea) was compared with Macro-Vue RPR Card Tests (Becton Dickinson BD Microbiology Systems, Sparks, Maryland, USA). Treponemal-specific tests were performed by Serodia TPPA assay (Fujirebio, Tokyo, Japan). The percentage agreement, κ value and overall sensitivity and specificity of the two RPR tests were compared. Seroconversion rates after treatment were also compared for each RPR test.

Results

The percentage agreement between the two RPR tests was 78.6% (κ 0.565; 95% CI 0.422 to 0.709). Sensitivity and specificity of the automated RPR test relative to the TPPA test was 52.5% (95% CI 39.1% to 65.7%) and 94.3% (95% CI 84.3% to 98.8%), respectively, while the same values for the conventional RPR card test were 86.4% (95% CI 75% to 93.9%) and 94.3% (95% CI 84.3% to 98.8%), respectively. The conventional RPR card test showed overall higher positivity than the automated RPR test, whereas the automated RPR test showed higher seroconversion (43.5%, 10/23) than the conventional RPR card test (4.3%, 1/23) in treated patients.

Conclusions

The automated RPR test showed overall lower sensitivity than the conventional RPR test based on the treponemal test, but higher seroconversion after treatment. The automated RPR test could be used to monitor treatment response, especially in the reverse screening algorithm in syphilis testing.
Trunk muscle exercises as a means of improving postural stability in people with Parkinson's disease: a protocol for a randomised controlled trial
Authors: Hubble Ryan P , Naughton Geraldine A , Silburn Peter A , Cole Michael H
Published: January 2015

Introduction

Exercise has been shown to improve clinical measures of strength, balance and mobility, and in some cases, has improved symptoms of tremor and rigidity in people with Parkinson's disease (PD). However, to date, no research has examined whether improvements in trunk control can remedy deficits in dynamic postural stability in this population. The proposed randomised controlled trial aims to establish whether a 12-week exercise programme aimed at improving dynamic postural stability in people with PD; (1) is more effective than education; (2) is more effective when training frequency is increased; and (3) provides greater long-term benefits than education.

Methods/design

Forty-five community-dwelling individuals diagnosed with idiopathic PD with a falls history will be recruited. Participants will complete baseline assessments including tests of cognition, vision, disease severity, fear of falling, mobility and quality of life. Additionally, participants will complete a series of standing balance tasks to evaluate static postural stability, while dynamic postural control will be measured during walking using head and trunk-mounted three-dimensional accelerometers. Following baseline testing, participants will be randomly-assigned to one of three intervention groups, who will receive either exercise once per week, exercise 3 days/week, or education. Participants will repeat the same battery of tests conducted at baseline after the 12-week intervention and again following a further 12-week sustainability period.

Discussion

This study has the potential to show that low-intensity and progressive trunk exercises can provide a non-invasive and effective means for maintaining or improving postural stability for people with PD. Importantly, if the programme is noted to be effective, it could be easily performed by patients within their home environment or under the guidance of available allied health professionals.

Trial registration number

The protocol for this study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12613001175763).
The effect on quality of life of vitamin D administration for advanced cancer treatment (VIDAFACT study): protocol of a randomised controlled trial
Authors: Martinez-Alonso Montserrat , Dusso Adriana , Ariza Gemma , Nabal Maria
Published: January 2015

Introduction

Vitamin D is related to resistance to chronic diseases, physiological parameters and functional measures. All of these relationships underscore the potential benefits of cholecalciferol or D3 (nutritional vitamin D) in cancer. This is the first study designed to obtain conclusive evidence on the effect of cholecalciferol in advanced patients with cancer. The main goal is to assess its effects on the patient's perceived quality of life. Cholecalciferol's impact on fatigue and physical performance, as well as its cost utility, will also be assessed.

Methods and analysis

A randomised triple-blind phase II/III placebo-controlled multicentre trial has been designed. Patients satisfying the inclusion and exclusion criteria will be randomly assigned to receive cholecalciferol or placebo. Eligible patients will be adults with a locally advanced or metastatic or inoperable solid cancer in palliative care, who have given signed informed consent and have matched inclusion and exclusion criteria. The randomisation will be based on a computer-generated procedure and centralised by the pharmacy service of the coordinating centre. The assigned treatment will be administered by the hospital's pharmacy to conceal group allocation for patients and healthcare providers. Cholecalciferol (4000 IU/day) or placebo, starting at day 15 and continuing up to day 42, will be added to palliative care treatment. Outpatient visits will be scheduled every 14 days.

Ethics and dissemination

Ethical approval was received from the Medical Ethical Commitee of the HUAV (CEIC-1169). Participants and their families will receive the research findings which will also be disseminated on local and national media, presented at national and international meetings of the specialty, and published in peer-reviewed scientific journals.

Trial registration number

EudraCT: 2013-003478-29.
Representations of the health value of vitamin D supplementation in newspapers: media content analysis
Authors: Caulfield Timothy , Clark Marianne I , McCormack James P , Rachul Christen , Field Catherine J
Published: January 2015

Objective

To examine the nature of media coverage of vitamin D in relation to its role in health and the need for supplements.

Design

Media content analysis.

Setting

Print articles from elite newspapers in the UK, the USA and Canada.

Participants

294 print newspaper articles appearing over 5 years (2009–2014).

Results

Newspaper coverage of vitamin D generally supported supplementation. The most common framing of vitamin D in print articles was “adequate vitamin D is necessary for good health.” Articles also framed vitamin D as difficult to obtain from food supply and framed vitamin D deficiency as a widespread concern. In discussions of supplementation, 80% articles suggested supplementation is or may be necessary for the general population, yet almost none of the articles discussed the potential harms of vitamin D supplementation in any detail.

Print articles named 40 different health conditions in relationship to vitamin D. The most commonly cited conditions included bone health, cancer and cardiovascular health. Although print articles referred to a wide range of scholarly research on vitamin D with varying degrees of endorsement for supplementation, a general tone of support for vitamin D supplementation in media coverage persisted.

Conclusions

Newspaper articles conveyed overall support for vitamin D supplementation. News articles linked vitamin D to a wide range of health conditions for which there is no conclusive scientific evidence. Media coverage downplayed the limitations of existing science and overlooked any potential risks associated with supplementation.
Neural biomarkers for assessing different types of imagery in pictorial health warning labels for cigarette packaging: a cross-sectional study
Authors: Newman-Norlund Roger D , Thrasher James F , Fridriksson Johann , Brixius William , Froeliger Brett , Hammond David , Cummings Michael K
Published: January 2015

Objective

Countries around the world have increasingly adopted pictorial health warning labels (HWLs) for tobacco packages to warn consumers about smoking-related risks. Research on how pictorial HWLs work has primarily analysed self-reported responses to HWLs; studies at the neural level comparing the brain's response to different types of HWLs may provide an important complement to prior studies, especially if self-reported responses are systematically biased. In this study we characterise the brain's response to three types of pictorial HWLs for which prior self-report studies indicated different levels of efficacy.

Methods

Current smokers rated pictorial HWLs and then observed the same HWLs during functional MRI (fMRI) scanning. Fifty 18–50-year-old current adult smokers who were free from neurological disorders were recruited from the general population and participated in the study. Demographics, smoking-related behaviours and self-reported ratings of pictorial HWL stimuli were obtained prior to scanning. Brain responses to HWLs were assessed using fMRI, focusing on a priori regions of interest.

Results

Pictorial HWL stimuli elicited activation in a broad network of brain areas associated with visual processing and emotion. Participants who rated the stimuli as more emotionally arousing also showed greater neural responses at these sites.

Conclusions

Self-reported ratings of pictorial HWLs are correlated with neural responses in brain areas associated with visual and emotional processing. Study results cross-validate self-reported ratings of pictorial HWLs and provide insights into how pictorial HWLs are processed.
Health system reforms, violence against doctors and job satisfaction in the medical profession: a cross-sectional survey in Zhejiang Province, Eastern China
Authors: Wu Dan , Wang Yun , Lam Kwok Fai , Hesketh Therese
Published: January 2015

Objective

To explore the factors influencing doctors’ job satisfaction and morale in China, in the context of the ongoing health system reforms and the deteriorating doctor–patient relationship.

Design

Cross-sectional survey using self-completion questionnaires.

Study setting

The survey was conducted from March to May 2012 among doctors at the provincial, county and primary care levels in Zhejiang Province, China.

Results

The questionnaire was completed by 202 doctors. Factors which contributed most to low job satisfaction were low income and long working hours. Provincial level doctors were most dissatisfied while primary care doctors were the least dissatisfied. Three per cent of doctors at high-level hospitals and 27% of those in primary care were satisfied with the salary. Only 7% at high-level hospitals were satisfied with the work hours, compared to 43% in primary care. Less than 10% at high levels were satisfied with the amount of paid vacation time (3%) and paid sick leave (5%), compared with 38% and 41%, respectively, in primary care. Overall, 87% reported that patients were more likely to sue and that patient violence against doctors was increasing. Only 4.5% wanted their children to be doctors. Of those 125 who provided a reason, 34% said poor pay, 17% said it was a high-risk profession, and 9% expressed concerns about personal insecurity or patient violence.

Conclusions

Doctors have low job satisfaction overall. Recruitment and retention of doctors have become major challenges for the Chinese health system. Measures must be taken to address this, in order to ensure recruitment and retention of doctors in the future. These measures must first include reduction of doctors’ workload, especially at provincial hospitals, partly through incentivisation of appropriate utilisation of primary care, increase in doctors’ salary and more effective measures to tackle patient violence against doctors.
A randomised controlled trial of aerobic exercise after transient ischaemic attack or minor stroke to prevent cognitive decline: the MoveIT study protocol
Authors: Boss H M , Van Schaik S M , Deijle I A , de Melker E C , van den Berg B T J , Scherder E J A , Bosboom W M J , Weinstein H C , Van den Berg-Vos R M
Published: January 2015

Introduction

Patients with transient ischaemic attack (TIA) or stroke are at risk for cognitive impairment and dementia. Currently, there is no known effective strategy to prevent this cognitive decline. Increasing evidence exists that physical exercise is beneficial for cognitive function. However, in patients with TIA or stroke who are at risk of cognitive impairment and dementia, only a few trials have been conducted. In this study, we aim to investigate whether a physical exercise programme (MoveIT) can prevent cognitive decline in patients in the acute phase after a TIA or minor ischaemic stroke.

Methods and analysis

A single-blinded randomised controlled trial will be conducted to investigate the effect of an aerobic exercise programme on cognition compared with usual care. 120 adult patients with a TIA or minor ischaemic stroke less than 1 month ago will be randomly allocated to an exercise programme consisting of a 12-week aerobic exercise programme and regular follow-up visits to a specialised physiotherapist during the period of 1 year or to usual care. Outcome measures will be assessed at the baseline, and at the 1-year and 2-year follow-up. The primary outcome is cognitive functioning measured with the Montreal Cognitive Assessment (MoCA) test and with additional neuropsychological tests. Secondary outcomes include maximal exercise capacity, self-reported physical activity and measures of secondary prevention.

Ethics and dissemination

The study received ethical approval from the VU University Amsterdam Ethics committee (2011/383). The results of this study will be published in peer-reviewed journals and presented at international conferences. We will also disseminate the main results to our participants in a letter.

Trial registration number

The Nederlands Trial Register NTR3884.
A randomised controlled non-inferiority trial of primary care-based facilitated access to an alcohol reduction website (EFAR Spain): the study protocol
Authors: López-Pelayo Hugo , Wallace Paul , Segura Lidia , Miquel Laia , Díaz Estela , Teixidó Lidia , Baena Begoña , Struzzo Pierliugio , Palacio-Vieira Jorge , Casajuana Cristina , Colom Joan , Gual Antoni
Published: January 2015

Introduction

Early identification (EI) and brief interventions (BIs) for risky drinkers are effective tools in primary care. Lack of time in daily practice has been identified as one of the main barriers to implementation of BI. There is growing evidence that facilitated access by primary healthcare professionals (PHCPs) to a web-based BI can be a time-saving alternative to standard face-to-face BIs, but there is as yet no evidence about the effectiveness of this approach relative to conventional BI. The main aim of this study is to test non-inferiority of facilitation to a web-based BI for risky drinkers delivered by PHCP against face-to-face BI.

Method and analysis

A randomised controlled non-inferiority trial comparing both interventions will be performed in primary care health centres in Catalonia, Spain. Unselected adult patients attending participating centres will be given a leaflet inviting them to log on to a website to complete the Alcohol Use Disorders Identification Test (AUDIT-C) alcohol screening questionnaire. Participants with positive results will be requested online to complete a trial module including consent, baseline assessment and randomisation to either face-to-face BI by the practitioner or BI via the alcohol reduction website. Follow-up assessment of risky drinking will be undertaken online at 3 months and 1 year using the full AUDIT and D5-EQD5 scale. Proportions of risky drinkers in each group will be calculated and non-inferiority assessed against a specified margin of 10%. Assuming reduction of 30% of risky drinkers receiving standard intervention, 1000 patients will be required to give 90% power to reject the null hypothesis.

Ethics and dissemination

The protocol was approved by the Ethics Commmittee of IDIAP Jordi Gol i Gurina P14/028. The findings of the trial will be disseminated through peer-reviewed journals, national and international conference presentations.

Trial registration number

ClinicalTrials.govNCT02082990.
‘Choosing Wisely’: a growing international campaign
Authors: Levinson Wendy , Kallewaard Marjon , Bhatia R Sacha , Wolfson Daniel , Shortt Sam , Kerr Eve A
Published: January 2015

Much attention has been paid to the inappropriate underuse of tests and treatments but until recently little attention has focused on the overuse that does not add value for patients and may even cause harm. Choosing Wisely is a campaign to engage physicians and patients in conversations about unnecessary tests, treatments and procedures. The campaign began in the United States in 2012, in Canada in 2014 and now many countries around the world are adapting the campaign and implementing it. This article describes the present status of Choosing Wisely programs in 12 countries. It articulates key elements, a set of five principles, and describes the challenges countries face in the early phases of Choosing Wisely. These countries plan to continue collaboration including developing metrics to measure overuse.
Prevalence and molecular characteristics of methicillin-resistantStaphylococcus aureusamong skin and soft tissue infections in an emergency department in Guyana
Authors: Dozois Adeline , Thomsen Isaac , Jimenez-Truque Natalia , Soper Nicole , Pearson Alexis , Mohamed-Rambaran Pheona , Dettorre Kristen B , Creech C Buddy , Wright Seth W
Published: January 2015

Objective

The characteristics of staphylococcal skin and soft tissue infections (SSTIs) are poorly understood in northern South America and the Caribbean. The objectives of this study were to determine the frequency of methicillin resistance amongStaphylococcus aureusisolates in an emergency department (ED) in Guyana and to identify specific molecular characteristics of these methicillin-resistantStaphylococcus aureus(MRSA) strains.

Methods

This was a cross-sectional study conducted at the main teaching hospital in Georgetown, Guyana. Eligible subjects included patients of all ages with SSTIs with obtainable purulent material. Purulent material was cultured, andS. aureusisolates were evaluated for antibiotic susceptibilities by disc diffusion. Molecular characterisation of MRSA isolates included identification of SCCmectype, assignment of genetic relatedness by rep-PCR and determination of the presence of two exotoxins, Panton-Valentine Leukocidin (PVL) and LukAB.

Results

Eighty-five samples were collected; of these, 47 grewS. aureus.24 of the 47S. aureussamples were MRSA (51%; 95% CI 37% to 65%), representing 28% of all samples. All MRSA isolates were SCCmectype IV, PVL positive, LukAB positive and were highly related to the current epidemic clone in the USA, USA300.

Conclusions

Here, we demonstrate a clinically significant proportion of methicillin resistance in SSTI-associated staphylococcal isolates. Guyanese isolates were highly related to the most common community-associated strain seen in the USA, USA300. These results have important implications for empiric antibiotic therapy and infection control policies in Guyana and similar settings.
Repeated attempts at tracheal intubation by a single intubator associated with decreased success rates in emergency departments: an analysis of a multicentre prospective observational study
Authors: Goto Tadahiro , Watase Hiroko , Morita Hiroshi , Nagai Hideya , Brown Calvin A , Brown David F M , Hasegawa Kohei
Published: January 2015

Objective

To determine whether the success rate of repeated attempts at tracheal intubation by a single intubator was lower than those by alternate intubators in the emergency department (ED).

Methods

An analysis of data from a multicentre prospective registry (Japanese Emergency Airway Network Registry) of 13 academic and community EDs in Japan between April 2010 and August 2012. We included all adult and paediatric patients who underwent repeated attempts at tracheal intubation in the ED. We compared the intubation success rates at the second and third attempts between attempts at intubation by a single intubator who performed the previous attempts, and the attempts by alternate intubators.

Results

We recorded 4094 patients (capture rate, 96%); 1289 patients with repeated attempts at tracheal intubation were eligible for this study. Among these, 871 patients (68%) had a second attempt at intubation by single intubators. At the second attempt, tracheal intubation by a single intubator was associated with a decreased success rate (adjusted odds ratio or AOR, 0.50; 95% CI 0.36 to 0.71), compared with alternate intubators. At the third attempt, intubation by a single intubator was also associated with a decreased success rate (58% vs 70%; unadjusted OR, 0.58; 95% CI 0.38 to 0.89). However, after adjustment for potential confounders, the association lost statistical significance (AOR, 0.89; 95% CI 0.52 to 1.56).

Conclusions

In this large multicentre study of ED patients undergoing tracheal intubation, second attempts at intubation by a single intubator, compared with those by alternate intubators, were independently associated with a decreased success rate.
Can VBG analysis replace ABG analysis in emergency care?
Authors: Kelly Anne-Maree
Published: January 2015

Blood gas analysis is an integral part of the assessment of emergency department (ED) patients with acute respiratory or metabolic disease. Traditionally ABG analyses have been used, but increasingly, emergency clinicians are using venous blood gas (VBG) analyses. This has been challenged, especially by respiratory physicians, as being too inaccurate. This clinical review, using case examples, summarises the evidence supporting use of VBG to guide management decisions. Arteriovenous agreement for pH is such that values are clinically interchangeable and agreement for bicarbonate is also close. Agreement for pCO2is poor with 95% limits of agreement of the order of 20 mm Hg (2.67 kPa); however, there is solid evidence that a venous pCO2≤45 mm Hg (6 kPa) reliably excludes clinically significant hypercarbia. Evidence regarding arteriovenous agreement for base excess is unclear. Given knowledge of the performance characteristics of VBG analyses, integration of the clinical findings with VBG results is often sufficient to safely guide treatment decision making.
Does undetectable troponin I at presentation using a contemporary sensitive assay rule out myocardial infarction? A cohort study
Authors: Kelly Anne-Maree , Klim Sharon
Published: January 2015

Aim

Recent evidence suggests that an undetectable troponin level at emergency department (ED) presentation can rule out the presence of myocardial infarction (MI) in low-risk patients. The aim of this study was to investigate whether an undetectable troponin I (TnI) level at presentation using a contemporary troponin assay can accurately rule out MI at various front-door thrombolysis in myocardial infarction (fTIMI) score cut-offs.

Methods

Planned substudy of a prospective observational cohort study of patients presenting to ED with chest pain without ECG evidence of ischaemia who underwent a ‘rule out’ acute coronary syndrome process. Clinical, investigational and outcome data were collected. A contemporary TnI assay (Siemens TnI Ultra) was used. Primary outcome of interest was diagnostic accuracy for MI of undetectable initial TnI at presentation at various fTIMI scores (sensitivity, specificity, positive predictive value and negative predictive value (NPV)).

Results

1076 patients were studied, of whom 156 had a final diagnosis of MI (14.5%). For patients with undetectable TnI and fTIMI scores 0, 0–1, 0–2 and 0–6, sensitivities were 98.7%, 98.1%, 97.4% and 97.4%, respectively, specificities were 22.6%, 41.7%, 53.8% and 69.9%, respectively, and NPV were 99%, 99.2%, 99.2% and 99.4%, respectively. If early presenters (<2 h of symptoms) were excluded, undetectable initial troponin had 100% sensitivity (95% CI 95.2% to 100%) and NPV (95% CI 98.8% to 100%).

Conclusions

Using a contemporary TnI assay, undetectable initial TnI has high but not perfect sensitivity and NPV, unless early presenters are excluded.

Trial registration number

ACTRN12612000990820.
A General Algorithm for Evaluating Domain Integrals in 2D Boundary Element Method for Transient Heat Conduction
Authors: Dong Yunqiao , Zhang Jianming , Xie Guizhong , Lu Chenjun , Li Yuan , Han Xu , Li Guangyao
Published: January 2015

A time-dependent boundary integral equation method named as pseudo-initial condition method is widely used to solve the transient heat conduction problems. Accurate evaluation of the domain integrals in the pseudo-initial condition formulation is of crucial importance for its successful implementation. As the time-dependent kernel in the domain integral is close to singular when small time step is used, a straightforward computation using Gaussian quadrature may produce large errors, and thus lead to instability of the analysis. To improve the computational accuracy of the domain integral, a coordinate transformation coupled with a domain cell subdivision technique is presented in this paper for 2D boundary element method. The coordinate transformation is denoted as (α, β) transformation, while the cell subdivision technique considers the position of the source point, the shape of the integration cell and the relations between the size of the cell and the time step. With the cell subdivision technique, more Gaussian points are shifted towards the source point, thus more accurate results can be obtained. Numerical examples have demonstrated the accuracy and efficiency of the proposed method.
HumanClostridium difficileinfection: inhibition of NHE3 and microbiota profile
Authors: Engevik Melinda A. , Engevik Kristen A. , Yacyshyn Mary Beth , Wang Jiang , Hassett Daniel J. , Darien Benjamin , Yacyshyn Bruce R. , Worrell Roger T.
Published: January 2015

Clostridium difficile infection (CDI) is principally responsible for hospital acquired, antibiotic-induced diarrhea and colitis and represents a significant financial burden on our healthcare system. Little is known about C. difficile proliferation requirements, and a better understanding of these parameters is critical for development of new therapeutic targets. In cell lines, C. difficile toxin B has been shown to inhibit Na+/H+exchanger 3 (NHE3) and loss of NHE3 in mice results in an altered intestinal environment coupled with a transformed gut microbiota composition. However, this has yet to be established in vivo in humans. We hypothesize that C. difficile toxin inhibits NHE3, resulting in alteration of the intestinal environment and gut microbiota. Our results demonstrate that CDI patient biopsy specimens have decreased NHE3 expression and CDI stool has elevated Na+and is more alkaline compared with stool from healthy individuals. CDI stool microbiota have increased Bacteroidetes and Proteobacteria and decreased Firmicutes phyla compared with healthy subjects. In vitro, C. difficile grows optimally in the presence of elevated Na+and alkaline pH, conditions that correlate to changes observed in CDI patients. To confirm that inhibition of NHE3 was specific to C. difficile, human intestinal organoids (HIOs) were injected with C. difficile or healthy and CDI stool supernatant. Injection of C. difficile and CDI stool decreased NHE3 mRNA and protein expression compared with healthy stool and control HIOs. Together these data demonstrate that C. difficile inhibits NHE3 in vivo, which creates an altered environment favored by C. difficile.
The mechanism of increased biliary lipid secretion in mice with genetic inactivation of bile salt export pump
Authors: Gooijert K. E. R. , Havinga R. , Wolters H. , Wang R. , Ling V. , Tazuma S. , Verkade H. J.
Published: January 2015

Human bile salt export pump ( BSEP) mutations underlie progressive familial intrahepatic cholestasis type 2 (PFIC2). In the PFIC2 animal model, Bsep−/−mice, biliary secretion of bile salts (BS) is decreased, but that of phospholipids (PL) and cholesterol (CH) is increased. Under physiological conditions, the biliary secretion of PL and CH is positively related (“coupled”) to that of BS. We aimed to elucidate the mechanism of increased biliary lipid secretion in Bsep−/−mice. The secretion of the BS tauro-β-muricholic acid (TβMCA) is relatively preserved in Bsep−/−mice. We infused Bsep−/−and Bsep+/+(control) mice with TβMCA in stepwise increasing dosages (150–600 nmol/min) and determined biliary bile flow, BS, PL, and CH secretion. mRNA and protein expression of relevant canalicular transporters was analyzed in livers from noninfused Bsep−/−and control mice. TβMCA infusion increased BS secretion in both Bsep−/−and control mice. The secreted PL or CH amount per BS, i.e., the “coupling,” was continuously two- to threefold higher in Bsep−/−mice ( P < 0.05). Hepatic mRNA expression of canalicular lipid transporters Mdr2, Abcg5, and Abcg8 was 45–55% higher in Bsep−/−mice (Abcg5; P < 0.05), as was canalicular Mdr2 and Abcg5 protein expression. Potential other explanations for the increased coupling of the biliary secretion of PL and CH to that of BS in Bsep−/−mice could be excluded. We conclude that the mechanism of increased biliary lipid secretion in Bsep−/−mice is based on increased expression of the responsible canalicular transporter proteins.
Influence of gonadal hormones on the behavioral effects of intermittent hypoxia in mice
Authors: Aubrecht Taryn G. , Jenkins Richelle , Magalang Ulysses J. , Nelson Randy J.
Published: January 2015

Obstructive sleep apnea (OSA) is characterized by repetitive upper airway obstruction resulting in cyclic intermittent hypoxia (IH) during sleep in affected individuals. OSA occurs more frequently in postmenopausal than premenopausal women and the severity of OSA increases after menopause. Gonadal hormones can influence brain and behavior; testosterone and estrogens in particular can enhance spatial learning and memory. We hypothesized that estrogens may protect mice from IH-induced hippocampal morphological and behavioral changes. To test this hypothesis we exposed intact or gonadectomized male and female mice to room air or IH [15 cycles/h, 8 h/day, fraction of inspired oxygen (FiO2) nadir of 5%] for a total of 30 days. During the final 4 days of IH, mice were tested for anxiety- and depressive-like behaviors. After cessation of IH exposure mice were tested on the Barnes maze and passive avoidance tests to assess learning and memory. Ovariectomy paired with IH treatment, impaired spatial learning and memory compared to all other female groups. Intact male mice receiving IH treatment also had impaired learning and memory compared with intact or castrated male mice exposed to room air. Learning and memory changes were mirrored by changes in basilar dendritic length of the CA1 region of the hippocampus. These data suggest that estrogens provide protection against IH-induced deficits, whereas androgens partially exacerbate IH-induced deficits on learning and memory.
Genetic knockdown of estrogen receptor-alpha in the subfornical organ augments ANG II-induced hypertension in female mice
Authors: Xue Baojian , Zhang Zhongming , Beltz Terry G. , Guo Fang , Hay Meredith , Johnson Alan Kim
Published: January 2015

The present study tested the hypotheses that 1) ERα in the brain plays a key role in the estrogen-protective effects against ANG II-induced hypertension, and 2) that the subfornical organ (SFO) is a key site where ERα mediates these protective actions. In this study, a “floxed” ERα transgenic mouse line (ERαflox) was used to create models in which ERα was knocked down in the brain or just in the SFO. Female mice with ERα ablated in the nervous system (Nestin-ERα−mice) showed greater increases in blood pressure (BP) in response to ANG II. Furthermore, females with ERα knockdown specifically in the SFO [SFO adenovirus-Cre (Ad-Cre) injected ERαfloxmice] also showed an enhanced pressor response to ANG II. Immunohistochemical (IHC), RT-PCR, and Western blot analyses revealed a marked reduction in the expression of ERα in nervous tissues and, in particular, in the SFO. These changes were not present in peripheral tissues in Nestin-ERα−mice or Ad-Cre-injected ERαfloxmice. mRNA expression of components of the renin-angiotensin system in the lamina terminalis were upregulated in Nestin-ERα−mice. Moreover, ganglionic blockade on day 7 after ANG II infusions resulted in a greater reduction of BP in Nestin-ERα−mice or SFO Ad-Cre-injected mice, suggesting that knockdown of ERα in the nervous system or the SFO alone augments central ANG II-induced increase in sympathetic tone. The results indicate that interfering with the action of estrogen on SFO ERα is sufficient to abolish the protective effects of estrogen against ANG II-induced hypertension.
Mechanisms of C-peptide-mediated rescue of low O2-induced ATP release from erythrocytes of humans with Type 2 diabetes
Authors: Richards Jennifer P. , Bowles Elizabeth A. , Gordon Weston R. , Ellsworth Mary L. , Stephenson Alan H. , Sprague Randy S.
Published: January 2015

The circulating erythrocyte, by virtue of the regulated release of ATP in response to reduced oxygen (O2) tension, plays a key role in maintaining appropriate perfusion distribution to meet tissue needs. Erythrocytes from individuals with Type 2 diabetes (DM2) fail to release ATP in response to this stimulus. However, the administration of C-peptide and insulin at a 1:1 ratio was shown to restore this important physiological response in humans with DM2. To begin to investigate the mechanisms by which C-peptide influences low O2-induced ATP release, erythrocytes from healthy humans and humans with DM2 were exposed to reduced O2in a thin-film tonometer, and ATP release under these conditions was compared with release during normoxia. We determined that 1) low O2-induced ATP release from DM2 erythrocytes is rescued by C-peptide in the presence and absence of insulin, 2) the signaling pathway activated by C-peptide in human erythrocytes involves PKC, as well as soluble guanylyl cyclase (sGC) and 3) inhibitors of cGMP degradation rescue low O2-induced ATP release from DM2 erythrocytes. These results provide support for the hypothesis that both PKC and sGC are components of a signaling pathway activated by C-peptide in human erythrocytes. In addition, since both C-peptide and phosphodiesterase 5 inhibitors rescue low O2-induced ATP release from erythrocytes of humans with DM2, their administration to humans with DM2 could aid in the treatment and/or prevention of the vascular disease associated with this condition.
Metabotropic glutamate receptors promote disinhibition of olfactory bulb glomeruli that scales with input strength
Authors: Zak Joseph D. , Whitesell Jennifer D. , Schoppa Nathan E.
Published: January 2015

Increasing evidence indicates that the neural circuitry within glomeruli of the olfactory bulb plays a major role in affecting information flow between olfactory sensory neurons (OSNs) and output mitral cells (MCs). Glutamatergic external tufted (ET) cells, located at glomeruli, can act as intermediary cells in excitation between OSNs and MCs, whereas activation of MCs by OSNs is, in turn, suppressed by inhibitory synapses onto ET cells. In this study, we used patch-clamp recordings in rat olfactory bulb slices to examine the function of metabotropic glutamate receptors (mGluRs) in altering these glomerular signaling mechanisms. We found that activation of group II mGluRs profoundly reduced inhibition onto ET cells evoked by OSN stimulation. The mGluRs that mediated disinhibition were located on presynaptic GABAergic periglomerular cells and appeared to be activated by glutamate transients derived from dendrites in glomeruli. In terms of glomerular output, the mGluR-mediated reduction in GABA release led to a robust increase in the number of action potentials evoked by OSN stimulation in both ET cells and MCs. Importantly, however, the enhanced excitation was specific to when a glomerulus was strongly activated by OSN inputs. By being selective for strong vs. weak glomerular activation, mGluR-mediated disinhibition provides a mechanism to enhance the contrast in odor signals that activate OSN inputs into a single glomerulus at varying intensities.
Cortical neural responses to previous trial outcome during learning of a directional choice task
Authors: Yuan Yuan , Mao Hongwei , Si Jennie
Published: January 2015

The outcomes that result from previous behavior affect future choices in several ways, but the neural mechanisms underlying these effects remain to be determined. Previous studies have shown that the lateral (AGl) and medial (AGm) agranular areas of the rat frontal cortex are involved in the learning and selection of action. Here we describe the activity of single neurons in AGl and AGm as rats learned to perform a directional choice task. Our analysis shows that single-cell activity in AGl and AGm was modulated by the outcome of the previous trial. A larger proportion of neurons encoded the previous trial's outcome shortly after cue onset than during other time periods of a trial. Most of these neurons had greater activity after correct trials than after error trials, a difference that increased as behavioral performance improved. The number of neurons encoding the previous trial's outcome correlated positively with performance accuracy. In summary, we found that neurons in both AGl and AGm encode the outcome of the immediately preceding trial, information that might play a role in the successful selection of action based on past experience.