bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genotypic and Phenotypic Traits That Distinguish Neonatal Meningitis-Associated Escherichia coli from Fecal E. coli Isolates of Healthy Human Hosts
Authors: Logue Catherine M. , Doetkott Curt , Mangiamele Paul , Wannemuehler Yvonne M. , Johnson Timothy J. , Tivendale Kelly A. , Li Ganwu , Sherwood Julie S. , Nolan Lisa K. 
Published: June 2012

ABSTRACT

Neonatal meningitis
Escherichia coli
(NMEC) is one of the top causes of neonatal meningitis worldwide. Here, 85 NMEC and 204 fecal
E. coli
isolates from healthy humans (HFEC) were compared for possession of traits related to virulence, antimicrobial resistance, and plasmid content. This comparison was done to identify traits that typify NMEC and distinguish it from commensal strains to refine the definition of the NMEC subpathotype, identify traits that might contribute to NMEC pathogenesis, and facilitate choices of NMEC strains for future study. A large number of
E. coli
strains from both groups were untypeable, with the most common serogroups occurring among NMEC being O18, followed by O83, O7, O12, and O1. NMEC strains were more likely than HFEC strains to be assigned to the B2 phylogenetic group. Few NMEC or HFEC strains were resistant to antimicrobials. Genes that best discriminated between NMEC and HFEC strains and that were present in more than 50% of NMEC isolates were mainly from extraintestinal pathogenic
E. coli
genomic and plasmid pathogenicity islands. Several of these defining traits had not previously been associated with NMEC pathogenesis, are of unknown function, and are plasmid located. Several genes that had been previously associated with NMEC virulence did not dominate among the NMEC isolates. These data suggest that there is much about NMEC virulence that is unknown and that there are pitfalls to studying single NMEC isolates to represent the entire subpathotype.
Differences in Virus Prevalence and Load in the Hearts of Patients with Idiopathic Dilated Cardiomyopathy with and without Immune-Mediated Inflammatory Diseases
Authors: Dennert Robert , van Paassen Pieter , Wolffs Petra , Bruggeman Catrien , Velthuis Sebastiaan , Felix Susanne , van Suylen Robert-Jan , Crijns Harry J. , Cohen Tervaert Jan Willem , Heymans Stephane 
Published: June 2012

ABSTRACTInfections with cardiotrophic viruses and immune-mediated responses against the heart have been suggested to play a dominant role in the pathogenesis of idiopathic dilated cardiomyopathy (DCM). Furthermore, immune-mediated inflammatory diseases (IMIDs) may result in DCM. It has not previously been assessed whether DCM patients with and without an IMID have different prevalences and quantities of cardiotrophic viruses in the heart. Therefore, we compared the profiles of cardiotrophic viruses in heart tissue of DCM patients with and without an IMID. Serum and myocardial tissue samples were obtained from 159 consecutive patients with DCM and 20 controls. Patients were subdivided into three groups, the first two based on the presence (n= 34) or absence (n= 125) of an IMID and the third being a control group. The parvovirus B19 virus genome was detected in equal quantities in the non-IMID DCM patients (100/125) and the control group (15/20) but in lower quantities in the IMID patients (21/34,P= 0.02). Both the non-IMID and IMID DCM patients demonstrated increased myocardial inflammation compared to controls: 12.5 ± 1.8 and 14.0 ± 3.2 CD45-positive inflammatory cells, respectively, versus 5.1 ± 0.7 for the controls (P< 0.05 for both). Importantly, significantly higher parvovirus B19 copy numbers could be amplified in non-IMID than in IMID patients (561 ± 97 versus 191 ± 92 copies/μg DNA,P< 0.001) and control subjects (103 ± 47 copies/μg DNA,P< 0.001). The present study shows decreased parvovirus B19 prevalence and copy numbers in hearts of DCM patients with an IMID compared to those without an IMID. These findings may suggest that DCM patients with an IMID have a different pathophysiologic mechanism from that which is present in the virus-induced form of DCM.
Peroxisomal and Mitochondrial β-Oxidation Pathways Influence the Virulence of the Pathogenic Fungus Cryptococcus neoformans
Authors: Kretschmer Matthias , Wang Joyce , Kronstad James W. 
Published: June 2012

ABSTRACT

An understanding of the connections between metabolism and elaboration of virulence factors during host colonization by the human-pathogenic fungus
Cryptococcus neoformans
is important for developing antifungal therapies. Lipids are abundant in host tissues, and fungal pathogens in the phylum basidiomycota possess both peroxisomal and mitochondrial β-oxidation pathways to utilize this potential carbon source. In addition, lipids are important signaling molecules in both fungi and mammals. In this report, we demonstrate that defects in the peroxisomal and mitochondrial β-oxidation pathways influence the growth of
C. neoformans
on fatty acids as well as the virulence of the fungus in a mouse inhalation model of cryptococcosis. Disease attenuation may be due to the cumulative influence of altered carbon source acquisition or processing, interference with secretion, changes in cell wall integrity, and an observed defect in capsule production for the peroxisomal mutant. Altered capsule elaboration in the context of a β-oxidation defect was unexpected but is particularly important because this trait is a major virulence factor for
C. neoformans
. Additionally, analysis of mutants in the peroxisomal pathway revealed a growth-promoting activity for
C. neoformans
, and subsequent work identified oleic acid and biotin as candidates for such factors. Overall, this study reveals that β-oxidation influences virulence in
C. neoformans
by multiple mechanisms that likely include contributions to carbon source acquisition and virulence factor elaboration.
A Listeria monocytogenes RNA Helicase Essential for Growth and Ribosomal Maturation at Low Temperatures Uses Its C Terminus for Appropriate Interaction with the Ribosome
Authors: Netterling Sakura , Vaitkevicius Karolis , Nord Stefan , Johansson Jörgen 
Published: June 2012

ABSTRACTListeria monocytogenes, a Gram-positive food-borne human pathogen, is able to grow at temperatures close to 0°C and is thus of great concern for the food industry. In this work, we investigated the physiological role of one DExD-box RNA helicase inListeria monocytogenes. The RNA helicase Lmo1722 was required for optimal growth at low temperatures, whereas it was dispensable at 37°C. A Δlmo1722strain was less motile due to downregulation of the major subunit of the flagellum, FlaA, caused by decreasedflaAexpression. By ribosomal fractionation experiments, it was observed that Lmo1722 was mainly associated with the 50S subunit of the ribosome. Absence of Lmo1722 decreased the fraction of 50S ribosomal subunits and mature 70S ribosomes and affected the processing of the 23S precursor rRNA. The ribosomal profile could be restored to wild-type levels in a Δlmo1722strain expressing Lmo1722. Interestingly, the C-terminal part of Lmo1722 was redundant for low-temperature growth, motility, 23S rRNA processing, and appropriate ribosomal maturation. However, Lmo1722 lacking the C terminus showed a reduced affinity for the 50S and 70S fractions, suggesting that the C terminus is important for proper guidance of Lmo1722 to the 50S subunit. Taken together, our results show that theListeriaRNA helicase Lmo1722 is essential for growth at low temperatures, motility, and rRNA processing and is important for ribosomal maturation, being associated mainly with the 50S subunit of the ribosome.
Structural Characterization of a Conserved, Calcium-Dependent Periplasmic Protease from Legionella pneumophila
Authors: Chatterjee Debashree , Boyd Chelsea D. , O'Toole George A. , Sondermann Holger 
Published: June 2012

ABSTRACTThe bacterial dinucleotide second messenger c-di-GMP has emerged as a central molecule in regulating bacterial behavior, including motility and biofilm formation. Proteins for the synthesis and degradation of c-di-GMP and effectors for its signal transmission are widely used in the bacterial domain. Previous work established the GGDEF-EAL domain-containing receptor LapD as a central switch inPseudomonas fluorescenscell adhesion. LapD senses c-di-GMP inside the cytosol and relays this signal to the outside by the differential recruitment of the periplasmic protease LapG. Here we identify the core components of an orthologous system inLegionella pneumophila. Despite only moderate sequence conservation at the protein level, key features concerning the regulation of LapG are retained. The output domain of the LapD-like receptor fromL. pneumophila, CdgS9, binds the LapG ortholog involving a strictly conserved surface tryptophan residue. While the endogenous substrate forL. pneumophilaLapG is unknown, the enzyme processed the correspondingP. fluorescenssubstrate, indicating a common catalytic mechanism and substrate recognition. Crystal structures ofL. pneumophilaLapG provide the first atomic models of bacterial proteases of the DUF920 family and reveal a conserved calcium-binding site important for LapG function.
LapG, Required for Modulating Biofilm Formation by Pseudomonasfluorescens Pf0-1, Is a Calcium-Dependent Protease
Authors: Boyd Chelsea D. , Chatterjee Debashree , Sondermann Holger , O'Toole George A. 
Published: June 2012

ABSTRACT

Biofilm formation by
Pseudomonas
fluorescens
Pf0-1 requires the cell surface adhesin LapA. We previously reported that LapG, a periplasmic cysteine protease of
P. fluorescens
, cleaves the N terminus of LapA, thus releasing this adhesin from the cell surface and resulting in loss of the ability to make a biofilm. The activity of LapG is regulated by the inner membrane-localized cyclic-di-GMP receptor LapD via direct protein-protein interactions. Here we present chelation and metal add-back studies demonstrating that calcium availability regulates biofilm formation by
P. fluorescens
Pf0-1. The determination that LapG is a calcium-dependent protease, based on
in vivo
and
in vitro
studies, explains the basis of this calcium-dependent regulation. Based on the crystal structure of LapG of
Legionella
pneumophila
in the accompanying report by Chatterjee and colleagues (D. Chatterjee et al., J. Bacteriol. 194:4415–4425, 2012), we show that the calcium-binding residues of LapG, D134 and E136, which are near the critical C135 active-site residue, are required for LapG activity of
P. fluorescens
in vivo
and
in vitro
. Furthermore, we show that mutations in D134 and E136 result in LapG proteins no longer able to interact with LapD, indicating that calcium binding results in LapG adopting a conformation competent for interaction with the protein that regulates its activity. Finally, we show that citrate, an environmentally relevant calcium chelator, can impact LapG activity and thus biofilm formation, suggesting that a physiologically relevant chelator of calcium can impact biofilm formation by this organism.
Influence of Herpes Simplex Virus 1 Latency-Associated Transcripts on the Establishment and Maintenance of Latency in the ROSA26R Reporter Mouse Model
Authors: Nicoll M. P. , Proença J. T. , Connor V. , Efstathiou S. 
Published: June 2012

ABSTRACT
Herpes simplex virus 1 (HSV-1) can establish life-long latent infection in sensory neurons, from which periodic reactivation can occur. During latency, viral gene expression is largely restricted to the latency-associated transcripts (LATs). While not essential for any phase of latency, to date the LATs have been shown to increase the efficiency of both establishment and reactivation of latency in small-animal models. We sought to investigate the role of LAT expression in the frequency of latency establishment within the ROSA26R reporter mouse model utilizing Cre recombinase-encoding recombinant viruses harboring deletions of the core LAT promoter (LAP) region. HSV-1 LAT expression was observed to influence the number of latently infected neurons in trigeminal but not dorsal root ganglia. Furthermore, the relative frequencies of latency establishment of LAT-positive and LAT-negative viruses are influenced by the inoculum dose following infection of the mouse whisker pads. Finally, analysis of the infected cell population at two latent time points revealed a relative loss of latently infected cells in the absence of LAT expression. We conclude that the HSV-1 LATs facilitate the long-term stability of the latent cell population within the infected host and that interpretation of LAT establishment phenotypes is influenced by infection methodology.
Avoiding handover fumbles: a controlled trial of a structured handover tool versus traditional handover methods
Authors: Payne Christina E , Stein Jason M , Leong Traci , Dressler Daniel D 
Published: June 2012

BackgroundHandover of patient information represents a critical time period during a patient's hospitalisation. While recent guidelines promote standardised communication during these patient care transitions, significant variability in structure and practice persists among hospitals and providers.MethodsThe authors surveyed internal medicine residents regarding handover practices before and after introduction of a structured, web-based handover application. The handover application standardised patient data in a format suitable for both patient handovers and day-to-day patient management.ResultsA total of 80 residents were surveyed prior to the intervention (80% response rate) and 161 residents during the intervention (average 68% response rate for all surveys distributed). At baseline, residents perceived deficits in handover practices related to the variability of information transferred and correlated that variability to near-miss events. After introduction of the handover application, 100% of handovers contained an updated problem list, active medications, and code status (compared to <55% at baseline, p<0.01); residents perceived approximately half as many near-miss events on call (31.5% vs 55%; p=0.0341) and were twice as likely to respond that they were confident or very confident in their patient handovers compared to traditional practices (93% vs 49%; p=0.01).ConclusionStandardisation of information transmitted during patient handovers through the use of a structured, web-based application led to consistent transfer of vital patient information and was associated with improved resident confidence and fewer perceived near-miss events on call.
Impact of online education on intern behaviour around joint commission national patient safety goals: a randomised trial
Authors: Shaw Tim J , Pernar Luise I , Peyre Sarah E , Helfrick John F , Vogelgesang Kaitlin R , Graydon-Baker Erin , Chretien Yves , Brown Elizabeth J , Nicholson James C , Heit Jeremy J , Co John Patrick T , Gandhi Tejal 
Published: June 2012

PurposeTo compare the effectiveness of two types of online learning methodologies for improving the patient-safety behaviours mandated in the Joint Commission National Patient Safety Goals (NPSG).MethodsThis randomised controlled trial was conducted in 2010 at Massachusetts General Hospital and Brigham and Women's Hospital (BWH) in Boston USA. Incoming interns were randomised to either receive an online Spaced Education (SE) programme consisting of cases and questions that reinforce over time, or a programme consisting of an online slide show followed by a quiz (SQ). The outcome measures included NPSG-knowledge improvement, NPSG-compliant behaviours in a simulation scenario, self-reported confidence in safety and quality, programme acceptability and programme relevance.ResultsBoth online learning programmes improved knowledge retention. On four out of seven survey items measuring satisfaction and self-reported confidence, the proportion of SE interns responding positively was significantly higher (p<0.05) than the fraction of SQ interns. SE interns demonstrated a mean 4.79 (36.6%) NPSG-compliant behaviours (out of 13 total), while SQ interns completed a mean 4.17 (32.0%) (p=0.09). Among those in surgical fields, SE interns demonstrated a mean 5.67 (43.6%) NPSG-compliant behaviours, while SQ interns completed a mean 2.33 (17.9%) (p=0.015). Focus group data indicates that SE was more contextually relevant than SQ, and significantly more engaging.ConclusionWhile both online methodologies improved knowledge surrounding the NPSG, SE was more contextually relevant to trainees and was engaging. SE impacted more significantly on both self-reported confidence and the behaviour of surgical residents in a simulated scenario.
Anaesthetic drug administration as a potential contributor to healthcare-associated infections: a prospective simulation-based evaluation of aseptic techniques in the administration of anaesthetic drugs
Authors: Gargiulo Derryn A , Sheridan Janie , Webster Craig S , Swift Simon , Torrie Jane , Weller Jennifer , Henderson Kaylene , Hannam Jacqueline , Merry Alan F 
Published: June 2012

ObjectiveTo evaluate the possibility that anaesthetists are administering potentially pathogenic micro-organisms to their patients.DesignProspective microbiological and observational study in a realistic simulated setting.ParticipantsTen anaesthetists supported by 10 anaesthetic technicians.Primary outcome measureThe presence or absence of organisms cultured from sterile intravenous bags used to collect drugs injected during the simulated cases and from the needles and the contents of the syringes used. The authors also observed the aseptic techniques used.ResultsOrganisms were isolated from five of 38 (13%) bags from five of 20 simulated cases anaesthetised by four of 10 anaesthetists, 10 of 197 (5%) syringes and six of 17 (35%) needles. None of the anaesthetists washed their hands prior to entry, used the hand gel provided, disinfected the phial septa before drawing up drugs or disinfected the intravenous ports on the intravenous administration set before use. One was seen to recap a needle left on a syringe for possible reuse. Three participants were observed to place equipment such as stethoscopes, drug charts and pens on top of their inuse drug trays.ConclusionThe administration of intravenous drugs during anaesthesia may be an important factor in the genesis (or potentially the prevention) of healthcare-associated infection. These observations suggest room for improvement in the aseptic techniques of at least some anaesthetists when preparing and administering intravenous drugs. Confirmation of these findings in clinical settings is needed.Study registry number (for the VASER study)Australian New Zealand Clinical Trials Registry: Ref: ACTRN 12609000530224,https://www.anzctr.org.au/registry/trial_review.aspx?ID=308128; note that the work presented here is a subset of the registered trial and its outcomes were not included in this registration.
Out-of-hospital cardiac arrest in Cork, Ireland
Authors: Henry Kieran , Murphy Adrian , Willis David , Cusack Stephen , Bury Gerard , O'Sullivan Iomhar , Deasy Conor 
Published: June 2012

BackgroundOut-of-hospital cardiac arrest (OHCA) in Ireland accounts for approximately 5000 deaths annually. Little published evidence exists on survival from OHCA in this country to date. We aimed to characterise and describe ‘presumed cardiac’ OHCA in Cork City and County attended by the Ambulance Service.MethodsDispatch records, ambulance patient records and hospital records for a 1-year period were examined for patient demographics, OHCA characteristics, interventions and patient outcomes.ResultsThere were 231 ‘presumed cardiac’ OHCAs attended over the study period; 130 (56%) were in urban locations and 101 (44%) in rural. OHCAs were lay-witnessed in 20% (n=46), and 22% (n=50) received bystander CPR. Shockable rhythm was present in 36 cases (16%) on initial assessment, and there was no difference in presence of shockable rhythm between urban and rural OHCAs (18% vs 13%, p=0.31). Resuscitation was attempted in 176 cases (77.5%), of whom 27 (15%) achieved return of spontaneous circulation and 13 (7.4%) survived to leave hospital. Survival when the initial rhythm was shockable was 16.7% (6 of 36 patients). Despite longer response times for rural compared with urban OHCAs (median (IQR) 16.5 (11.0–23.5) vs 9 (7–12) min, p<0.001), survival to leave hospital alive where resuscitation was attempted was similar (7.4% vs 7.4%, p=0.99, respectively).ConclusionA survival rate of 16.7% in shockable rhythms indicates scope for improvement which would influence the overall survival rate which was found to be 7.4%. Real-time feedback of performance and quality of the continuum of patient care through a clinical-quality cardiac arrest registry would monitor and incentivise such initiatives.
Improving the diagnosis of central nervous system infections in adults through introduction of a simple lumbar puncture pack
Authors: Michael Benedict Daniel , Powell Graham , Curtis Sarah , Bailey Lisa , Almond Solomon , McGill Fiona , Cousins David , Hart Ian J , Griffiths Michael , Kneen Rachel , Solomon Tom 
Published: June 2012

BackgroundAcute central nervous system (CNS) infections, such as meningitis and encephalitis, are neurological emergencies for which accurate diagnosis and prompt treatment improve the outcome. Analysis of the cerebrospinal fluid (CSF) obtained at lumbar puncture (LP) is pivotal to establishing the diagnosis and guiding management. PCR analysis of the CSF is an important method to identify the pathogen. However, recent studies have demonstrated that many patients have inadequate CSF sample collection and analysis.AimsTo increase the proportion of patients having an LP for a suspected CNS infection for whom the appropriate samples are taken. Secondary aims included to increase the proportion of patients for whom a pathogen was identified.MethodsThe authors developed an LP pack for patients with a suspected CNS infection. They also assessed its impact on diagnosis by comparing practice 6 months before and after its introduction to the medical admissions unit of a large inner city teaching hospital.ResultsThe authors found that the LP pack reduced major errors in CSF sample collection and improved the diagnosis of acute CNS infections; among those patients who had a CSF pleocytosis, the proportion with a viral or bacterial pathogen identified by PCR was increased after introduction of the pack.DiscussionThis study has demonstrated that the introduction of a simple low-cost LP pack into a busy acute medical setting can improve the diagnosis of CNS infections and, thus, guide treatment. Further work is needed to see if these results are more widely reproducible, and to examine the clinical, health and economic impact on overall management of patients with suspected CNS infections.