230 research outputs found
Dual-Targeting of NADP+-Isocitrate Dehydrogenase
Many mitochondrial and chloroplast proteins are encoded in the nucleus and subsequently imported into the organelles via active protein transport systems. While usually highly specific, some proteins are dual-targeted to both organelles. In tobacco (Nicotiana tabacum L.), the cDNA encoding the mitochondrial isoform of NADP+-dependent isocitrate dehydrogenase (NADP+-ICDH) contains two translational ATG start sites, indicating the possibility of two tandem targeting signals. In this work the putative mitochondrial and chloroplastic targeting signals from NADP+-ICDH were fused to a yellow fluorescent protein (YFP) to generate a series of constructs and introduced into tobacco leaves by Agrobacterium-mediated transient transfection. The subsequent sub-cellular locations of the ICDH:YFP fusion proteins were then examined under the confocal microscope. Constructs predicted to be targeted to the chlroplast all localized to the chloroplast. However, this was not the case for constructs that were predicted to be mitochondrial targeted. While some constructs localized to mitochondria, others appeared to be chloroplast localized. This was attributed to an additional 50 amino acid residues of the mature NADP+-ICDH protein which was present in those constructs. In addition, during the process of generating these constructs our sequence analysis indicated a stop codon present at amino acid position 161 of the mature NADP+-ICDH protein from both Xanthi and Petit Havana cultivars of tobacco. This was confirmed by multiple sequencing reactions and created discrepancies with the reported sequence present in the database. The results of this study raise interesting questions with regard to the targeting and processing of NADP+-ICDH
The impact of freight transport capacity limitations on supply chain dynamics
We investigate how capacity limitations in the transportation system affect the dynamic behaviour of supply chains. We are interested in the more recently defined, 'backlash' effect. Using a system dynamics simulation approach, we replicate the well-known Beer Game supply chain for different transport capacity management scenarios. The results indicate that transport capacity limitations negatively impact on inventory and backlog costs, although there is a positive impact on the 'backlash' effect. We show that it is possible for both backlog and inventory to simultaneous occur, a situation which does not arise with the uncapacitated scenario. A vertical collaborative approach to transport provision is able to overcome such a trade-off. © 2013 Taylor & Francis
Characterising encapsulated nuclear waste using cosmic-ray muon tomography
Tomographic imaging techniques using the Coulomb scattering of cosmic-ray
muons have been shown previously to successfully identify and characterise low-
and high-Z materials within an air matrix using a prototype scintillating-fibre
tracker system. Those studies were performed as the first in a series to assess
the feasibility of this technology and image reconstruction techniques in
characterising the potential high-Z contents of legacy nuclear waste containers
for the UK Nuclear Industry. The present work continues the feasibility study
and presents the first images reconstructed from experimental data collected
using this small-scale prototype system of low- and high-Z materials
encapsulated within a concrete-filled stainless-steel container. Clear
discrimination is observed between the thick steel casing, the concrete matrix
and the sample materials assayed. These reconstructed objects are presented and
discussed in detail alongside the implications for future industrial scenarios.Comment: 6 pages, 4 figure
Sustained improvement in vancomycin dosing and monitoring post-implementation of guidelines: Results of a three-year follow-up after a multifaceted intervention in an Australian teaching hospital
Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Introduction
Despite vancomycin being in use for over half-a-century, it is still not dosed or monitored appropriately in many centers around the world. The objective of this study was to determine the effectiveness of a multifaceted intervention to implement a vancomycin dosing and monitoring guideline across multiple medical and surgical units over time.
Methods
This was an observational before-and-after interventional cohort study. The pre-intervention period was August to December 2010–2011 and the post-intervention period was September to November 2012–2014. The implementation strategy comprised: face-to-face education, online continuing medical education, dissemination of pocket guideline and email reminder. Outcome measures included: appropriate prescribing of loading and maintenance doses, therapeutic drug monitoring, time to attain target range and nephrotoxicity.
Results
Post-implementation prescribing of loading doses increased (10.4%–43.6%, P=<0.001), guideline adherent first maintenance dose (44%–68.4% P = 0.04), correct dose adjustment from (53.1%–72.2%, P = 0.009). Beneficial effects pre and post-implementation were observed for adherent timing of initial concentration (43.2%–51.9%, P = 0.01), concentrations in target range (32.6%–44.1%, P = 0.001), time to target range (median 6–4 days, P=<0.001), potentially nephrotoxic concentrations (30.7%–20.9%, P=<0.001) and nephrotoxicity (10.4%–6.8%, P=<0.001).
Conclusions
A multifaceted intervention to implement a vancomycin dosing and monitoring guideline significantly improved prescribing, monitoring, pharmacokinetic and safety outcomes for patients treated with vancomycin over an extended period. However, increased guideline adoption by clinicians is required to maximize and prolong the utility of this important agent
Interventions Targeting the Prescribing and Monitoring of Vancomycin for Hospitalized Patients: A Systematic Review Protocol
This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Introduction
Vancomycin remains one of our essential antibiotics after fifty years of treating serious infections such as methicillin-resistant Staphylococcus aureus. Vancomycin, unlike many other antibiotic agents, requires individualized dosing and monitoring of serum drug levels to ensure it is efficacious, to minimize toxicity, and to limit the development of antibiotic resistance. These issues have led to numerous vancomycin clinical practice guidelines being published in recent years including several key national guidelines. Significant resources are invested during the development of such guidelines; however, there is often little or no information about how such guidelines or other vancomycin practice improvement initiatives should be implemented. The aim of this systematic review is to identify and evaluate the effect of interventions using education, guideline implementation, and dissemination of educational resources that have sought to improve therapeutic drug monitoring and dosing of vancomycin.
Methods
A systematic review of the literature will be conducted for RCTs and observational studies where a vancomycin guideline or practice improvement initiative has been implemented. Electronic databases to be searched are PubMed, Medline, CINAHL, EMBASE and the Cochrane Library of Systematic Reviews. The population will be patients who have had intravenous vancomycin prescribed and monitored in hospital. The interventions will be education, implementation of guidelines or protocols, dissemination of educational materials (printed or electronic) or multifaceted interventions of the above. The comparator will be patients who have had standard-care prescribing and monitoring of vancomycin. Outcomes will be changes in prescribing and ordering of vancomycin serum tests, and serum levels attained in patients as well as reported nephrotoxicity. Two reviewers will be involved in the quality assessment and extraction of data. The Scottish Intercollegiate Guidelines Network checklist for RCTs will be used. Studies that are not randomized will be assessed for quality using the validated ROBINS-I (risk of bias in non-randomized studies of interventions) tool.
Discussion
This systematic review will identify interventions that have been used to implement guidelines and clinical practice initiatives for vancomycin. The findings of this review may be informative to those involved with the implementation of vancomycin clinical practice guidelines.
Systematic review registration: PROSPERO: CRD42016049147
HLA-Bw4 Homozygosity Is Associated with an Impaired CD4 T Cell Recovery after Initiation of Antiretroviral Therapy
We assessed the influence of human leukocyte antigen (HLA) alleles HLA-Bw4 and HLA-Bw6 on CD4 T cell recovery after starting successful combination antiretroviral therapy in 265 individuals. The median gains in the CD4 T cell count after 4 years were 258 cells/µL for HLA-Bw4 homozygotes, 321 cells/µL for HLA-Bw4/Bw6 heterozygotes, and 363 cells/µL for HLA-Bw6 homozygotes (P=.01, compared with HLA-Bw4 homozygotes). HLA-Bw4 homozygosity appears to predict an impaired CD4 T cell recovery after initiation of combination antiretroviral therap
Interventions targeting the prescribing and monitoring of vancomycin for hospitalized patients: a systematic review with meta-analysis
Copyright © 2018 Phillips et al. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed.Purpose: Vancomycin prescribing requires individualized dosing and monitoring to ensure efficacy, limit toxicity, and minimize resistance. Although there are nationally endorsed guidelines from several countries addressing the complexities of vancomycin dosing and monitoring, there is limited consideration of how to implement these recommendations effectively.
Methods: We conducted a systematic search of multiple databases to identify relevant comparative studies describing the impact of interventions of educational meetings, implementation of guidelines, and dissemination of educational material on vancomycin dosing, monitoring, and nephrotoxicity. Effect size was assessed using ORs and pooled data analyzed using forest plots to provide overall effect measures.
Results: Six studies were included. All studies included educational meetings. Two studies used implementation of guidance, educational meetings, and dissemination of educational materials, one used guidance and educational meetings, one educational meetings and dissemination of educational materials, and two used educational meetings solely. Effect sizes for individual studies were more likely to be significant for multifaceted interventions. In meta-analysis, the overall effect of interventions on outcome measures of vancomycin dosing was OR 2.50 (95% CI 1.29–4.84); P< 0.01. A higher proportion of sampling at steady-state concentration was seen following intervention (OR 1.95, 95% CI 1.26–3.02; P<0.01). Interventions had no effect on appropriate timing of trough sample (OR 2.02, 95% CI 0.72–5.72; P=0.18), attaining target concentration in patients (OR 1.50, 95% CI 0.49–4.63; P=0.48, or nephrotoxicity (OR 0.75, 95% CI 0.42–1.34; P=0.33).
Conclusion: Multifaceted interventions are effective overall in improving the complex task of dosing vancomycin, as well as some vancomycin-monitoring outcome measures. However, the resulting impact of these interventions on efficacy and toxicity requires further investigation. These findings may be helpful to those charged with designing implementation strategies for vancomycin guidelines or complex prescribing processes in hospitals
K 1-6: an asymmetric planetary nebula with a binary central star
We present new imaging data and archival multiwavelength observations of the
little studied emission nebula K 1-6 and its central star. Narrow-band images
in H-alpha (+ [NII]) and [OIII] taken with the Faulkes Telescope North reveal a
stratified, asymmetric, elliptical nebula surrounding a central star which has
the colours of a late G- or early K-type subgiant or giant. GALEX ultraviolet
images reveal a very hot subdwarf or white dwarf coincident in position with
this star. The cooler, optically dominant star is strongly variable with a
period of 21.312 +/- 0.008 days, and is possibly a high amplitude member of the
RS CVn class, although an FK Com classification is also possible. Archival
ROSAT data provide good evidence that the cool star has an active corona. We
conclude that K 1-6 is most likely an old bona fide planetary nebula at a
distance of ~1.0 kpc, interacting with the interstellar medium, and containing
a binary or ternary central star. The observations and data analyses reported
in this paper were conducted in conjunction with Year 11 high school students
as part of an Australian Research Council Linkage Grant science education
project, denoted Space To Grow, conducted jointly by professional astronomers,
educational researchers, teachers, and high-school students.Comment: 13 pages, 5 figures, accepted by the Publications of the Astronomical
Society of Australia (PASA
Safety and efficacy of hydroxychloroquine as prophylactic against COVID-19 in healthcare workers: a meta-analysis of randomised clinical trials
OBJECTIVE: We studied the safety and efficacy of hydroxychloroquine (HCQ) as pre-exposure prophylaxis for COVID-19 in healthcare workers (HCWs), using a meta-analysis of randomised controlled trials (RCTs).
DATA SOURCES: PubMed and EMBASE databases were searched to identify randomised trials studying HCQ.
STUDY SELECTION: Ten RCTs were identified (n=5079 participants).
DATA EXTRACTION AND SYNTHESIS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in this systematic review and meta-analysis between HCQ and placebo using a Bayesian random-effects model. A pre-hoc statistical analysis plan was written.
MAIN OUTCOMES: The primary efficacy outcome was PCR-confirmed SARS-CoV-2 infection and the primary safety outcome was incidence of adverse events. The secondary outcome included clinically suspected SARS-CoV-2 infection.
RESULTS: Compared with placebo, HCWs randomised to HCQ had no significant difference in PCR-confirmed SARS-CoV-2 infection (OR 0.92, 95% credible interval (CI): 0.58, 1.37) or clinically suspected SARS-CoV-2 infection (OR 0.78, 95% CI: 0.57, 1.10), but significant difference in adverse events (OR 1.35, 95% CI: 1.03, 1.73).
CONCLUSIONS AND RELEVANCE: Our meta-analysis of 10 RCTs investigating the safety and efficacy of HCQ as pre-exposure prophylaxis in HCWs found that compared with placebo, HCQ does not significantly reduce the risk of confirmed or clinically suspected SARS-CoV-2 infection, while HCQ significantly increases adverse events.
PROSPERO REGISTRATION NUMBER: CRD42021285093
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