250 research outputs found

    The diagnositic test accuracy of serum procalcitonin compared to C-reactive protein for bone and joint infection in children and adolescents: A Systematic review and Meta-analysis

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    Objective: To synthesise the best available evidence for the diagnostic test accuracy of measurement of serum procalcitonin compared to serum C-reactive protein for suspected osteomyelitis and septic arthritis in hospitalised children and adolescents. Introduction: Measurement of serum C-reactive protein remains a routine investigation for the diagnosis of osteoarticular infection in children and adolescents. Measurement of serum procalcitonin has been shown to outperform C-reactive protein in adults with osteomyelitis and septic arthritis. Before procalcitonin can be considered as a potential replacement or additional test in children and adolescents, a systematic review and meta-analysis targeting this population is needed. Inclusion criteria: Original studies reporting on the diagnostic accuracy of procalcitonin and/or C-reactive protein in children and adolescents aged between one month and 18 years admitted to hospital with suspected osteoarticular infection were included, compared to at least one reference test. The reference test was defined as positive culture or polymerase chain reaction confirmation of a pathogen from blood and/or bone biopsy and/or joint fluid aspirate and/or at least two of the following: 1) purulent material from sterile site; 2) positive radiological findings consistent with osteoarticular infection; 3) symptoms and signs consistent with osteomyelitis and/or septic arthritis. Methods: JBI methodology for systematic reviews of diagnostic test accuracy was employed. Information was sourced from four databases; MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Web of Science and four grey literature sources; Mednar, OpenGrey, Google scholar and ProQuest Dissertations and Thesis. Only studies published in English were considered. The methodological quality of selected studies was formally evaluated and sensitivity and specificity data were extracted and 95% confidence intervals determined. Meta-analysis was performed to estimate summary points using a bivariate model and generate a hierarchial summary receiver operating characteristic curve (HSROC) with global measures of test accuracy performance including likelihood ratio and diagnostic odds ratio. A narrative summary was provided where meta-analysis was not feasible. Results: Eight out of 3086 studies were included in the final analysis. Four of these studies used a common CRP test threshold of 20mg/L for septic arthritis cases only. At this threshold the estimated pooled sensitivity of C-reactive protein was 0.86 (0.68-0.96) and the pooled specificity 0.9 (0.83-0.94). Using a HSROC model from six studies including all osteoarticular infections, the diagnostic odds ratio for C-reactive protein was estimated to be 39.4 (14.8-104.9) with a positive likelihood ratio 5.3 (2.3-11.9) and negative likelihood ratio 0.1 (0.07-0.2). There were insufficient studies from this review to statistically evaluate the diagnostic accuracy performance of procalcitonin using meta-analysis. Conclusion: We have synthesised the best available evidence to evaluate the diagnostic test accuracy of serum measurement of procalcitonin and C-reactive protein in children and adolescents with suspected osteomyelitis and septic arthritis. Clinicians should continue to measure serum C-reactive protein as the preferred inflammatory marker in this setting and await more evidence before incorporating procalcitonin routinely into their diagnostic test strategy for this specific setting.Thesis (MClinSc) -- University of Adelaide, School of Public Health, 202

    Genetic and biochemical characterization of an acquired subgroup B3 metallo-β-lactamase gene, blaAIM-1, and its unique genetic context in Pseudomonas aeruginosa from Australia

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    Three clinical Pseudomonas aeruginosa isolates (WCH2677, WCH2813, and WCH2837) isolated from the Women's and Children's Hospital, Adelaide, Australia, produced a metallo-β-lactamase (MBL)-positive Etest result. All isolates were PCR negative for known MBL genes. A gene bank was created, and an MBL gene, designated bla, was cloned and fully characterized. The encoded enzyme, AIM-1, is a group B3 MBL that has the highest level of identity to THIN-B and L1. It is chromosomal and flanked by two copies (one intact and one truncated) of an ISCR element, ISCR15. Southern hybridization studies indicated the movement of both ISCR15 and bla within the three different clinical isolates. AIM-1 hydrolyzes most β-lactams, with the exception of aztreonam and, to a lesser extent, ceftazidime; however, it possesses significantly higher k values for cefepime and carbapenems than most other MBLs. AIM-1 was the first mobile group B3 enzyme detected and signals further problems for already beleaguered antimicrobial regimes to treat serious P. aeruginosa and other Gram-negative infections

    Alternative contingency table measures improve the power and detection of multifactor dimensionality reduction

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    <p>Abstract</p> <p>Background</p> <p>Multifactor Dimensionality Reduction (MDR) has been introduced previously as a non-parametric statistical method for detecting gene-gene interactions. MDR performs a dimensional reduction by assigning multi-locus genotypes to either high- or low-risk groups and measuring the percentage of cases and controls incorrectly labelled by this classification – the classification error. The combination of variables that produces the lowest classification error is selected as the best or most fit model. The correctly and incorrectly labelled cases and controls can be expressed as a two-way contingency table. We sought to improve the ability of MDR to detect gene-gene interactions by replacing classification error with a different measure to score model quality.</p> <p>Results</p> <p>In this study, we compare the detection and power of MDR using a variety of measures for two-way contingency table analysis. We simulated 40 genetic models, varying the number of disease loci in the model (2 – 5), allele frequencies of the disease loci (.2/.8 or .4/.6) and the broad-sense heritability of the model (.05 – .3). Overall, detection using NMI was 65.36% across all models, and specific detection was 59.4% versus detection using classification error at 62% and specific detection was 52.2%.</p> <p>Conclusion</p> <p>Of the 10 measures evaluated, the likelihood ratio and normalized mutual information (NMI) are measures that consistently improve the detection and power of MDR in simulated data over using classification error. These measures also reduce the inclusion of spurious variables in a multi-locus model. Thus, MDR, which has already been demonstrated as a powerful tool for detecting gene-gene interactions, can be improved with the use of alternative fitness functions.</p

    Protocol for a randomised crossover trial to evaluate patient and nurse satisfaction with electronic and elastomeric portable infusion pumps for the continuous administration of antibiotic therapy in the home: the Comparing Home Infusion Devices (CHID) study

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    This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/Introduction Previous studies comparing satisfaction with electronic and elastomeric infusion pumps are limited, and improvements in size and usability of electronic pumps have since occurred. The Comparing Home Infusion Devices (CHID) study plans to assess patient and nurse satisfaction with an elastomeric and electronic pump for delivering intravenous antibiotic treatment in the home. Secondary objectives are to determine pump-related complications and actual antibiotic dose administered, evaluate temperature variation and compare pump operating costs. Methods and analysis The CHID study will be a randomised, crossover trial. A trained research nurse will recruit patients with infectious disease aged ≥18 years and prescribed ≥8 days of continuous intravenous antibiotic therapy from the Royal Adelaide Hospital (RAH) (Adelaide, Australia). Patients will be randomised to receive treatment at home via an elastomeric (Baxter Infusor) or an electronic (ambIT Continuous) infusion pump for 4–7 days, followed by the other for a further 4–7 days. Patient satisfaction will be assessed by a 10-item survey to be completed at the end of each arm. Nurse satisfaction will be assessed by a single 24-item survey. Patient logbooks and case notes from clinic visits will be screened to identify complications. Pumps/infusion bags will be weighed to estimate the volume of solution delivered. Temperature sensors will record skin and ambient temperatures during storage and use of the pumps throughout the infusion period. Costs relating to pumps, consumables, antibiotics and servicing will be determined. Descriptive statistics will summarise study data

    Defending the scientific integrity of conservation-policy processes

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    Government agencies faced with politically controversial decisions often discount or ignore scientific information, whether from agency staff or nongovernmental scientists. Recent developments in scientific integrity (the ability to perform, use, communicate, and publish science free from censorship or political interference) in Canada, Australia, and the United States demonstrate a similar trajectory. A perceived increase in scientific‐integrity abuses provokes concerted pressure by the scientific community, leading to efforts to improve scientific‐integrity protections under a new administration. However, protections are often inconsistently applied and are at risk of reversal under administrations publicly hostile to evidence‐based policy. We compared recent challenges to scientific integrity to determine what aspects of scientific input into conservation policy are most at risk of political distortion and what can be done to strengthen safeguards against such abuses. To ensure the integrity of outbound communications from government scientists to the public, we suggest governments strengthen scientific integrity policies, include scientists&rsquo; right to speak freely in collective‐bargaining agreements, guarantee public access to scientific information, and strengthen agency culture supporting scientific integrity. To ensure the transparency and integrity with which information from nongovernmental scientists (e.g., submitted comments or formal policy reviews) informs the policy process, we suggest governments broaden the scope of independent reviews, ensure greater diversity of expert input and transparency regarding conflicts of interest, require a substantive response to input from agencies, and engage proactively with scientific societies. For their part, scientists and scientific societies have a responsibility to engage with the public to affirm that science is a crucial resource for developing evidence‐based policy and regulations in the public interest

    Counting the bodies: Estimating the numbers and spatial variation of Australian reptiles, birds and mammals killed by two invasive mesopredators

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    Aim Introduced predators negatively impact biodiversity globally, with insular fauna often most severely affected. Here, we assess spatial variation in the number of terrestrial vertebrates (excluding amphibians) killed by two mammalian mesopredators introduced to Australia, the red fox (Vulpes vulpes) and feral cat (Felis catus). We aim to identify prey groups that suffer especially high rates of predation, and regions where losses to foxes and/or cats are most substantial. Location Australia. Methods We draw information on the spatial variation in tallies of reptiles, birds and mammals killed by cats in Australia from published studies. We derive tallies for fox predation by (i) modelling continental-scale spatial variation in fox density, (ii) modelling spatial variation in the frequency of occurrence of prey groups in fox diet, (iii) analysing the number of prey individuals within dietary samples and (iv) discounting animals taken as carrion. We derive point estimates of the numbers of individuals killed annually by foxes and by cats and map spatial variation in these tallies. Results Foxes kill more reptiles, birds and mammals (peaking at 1071 km−2 year−1) than cats (55 km−2 year−1) across most of the unmodified temperate and forested areas of mainland Australia, reflecting the generally higher density of foxes than cats in these environments. However, across most of the continent – mainly the arid central and tropical northern regions (and on most Australian islands) – cats kill more animals than foxes. We estimate that foxes and cats together kill 697 million reptiles annually in Australia, 510 million birds and 1435 million mammals. Main conclusions This continental-scale analysis demonstrates that predation by two introduced species takes a substantial and ongoing toll on Australian reptiles, birds and mammals. Continuing population declines and potential extinctions of some of these species threatens to further compound Australia's poor contemporary conservation record
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