208 research outputs found

    Polyanionic Ligand Platforms for Methyl- and Dimethylaluminum Arrays

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    Trimethylaluminum finds widespread applications in chemical and materials synthesis, most prominently in its partially hydrolyzed form of methylalumoxane (MAO), which is used as a cocatalyst in the polymerization of olefins. This work investigates the sequential reactions of trimethylaluminum with hexaprotic phosphazenes (RNH)6P3N3 (=XH6) equipped with substituents R of varied steric bulk including tert-butyl (1H6), cyclohexyl (2H6), isopropyl (3H6), isobutyl (4H6), ethyl (5H6), propyl (6H6), methyl (7H6), and benzyl (8H6). Similar to MAO, the resulting complexes of polyanionic phosphazenates [XHn]n−6 accommodate multinuclear arrays of [AlMe2]+ and [AlMe]2+. Reactions were monitored by 31P NMR spectroscopy, and structures were determined by single-crystal X-ray diffraction. They included 1H4(AlMe2)2, 1H3(AlMe2)3, 2H3(AlMe2)3, 3(AlMe2)4AlMe, 4H­(AlMe2)5, 4(AlMe2)6, {5H­(AlMe2)4}2AlMe, 5(AlMe2)6, 6(AlMe2)6, {7(AlMe2)4AlMe}2, and 8(AlMe2)6. The study shows that subtle variations of the steric properties of the R groups influence the reaction pathways, levels of aggregation, and fluxional behavior. While [AlMe2]+ is the primary product of the metalation, [AlMe]2+ is utilized to alleviate overcrowding or to aid aggregation. At the later stages of metalation, [AlMe2]+ groups start to scramble around congested sites. The ligands proved to be very robust and extremely flexible, offering a unique platform to study complex multinuclear metal arrangements

    Prevalence of Chlamydia trachomatis

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    Investigating and learning lessons from early experiences of implementing ePrescribing systems into NHS hospitals:a questionnaire study

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    Background: ePrescribing systems have significant potential to improve the safety and efficiency of healthcare, but they need to be carefully selected and implemented to maximise benefits. Implementations in English hospitals are in the early stages and there is a lack of standards guiding the procurement, functional specifications, and expected benefits. We sought to provide an updated overview of the current picture in relation to implementation of ePrescribing systems, explore existing strategies, and identify early lessons learned.Methods: a descriptive questionnaire-based study, which included closed and free text questions and involved both quantitative and qualitative analysis of the data generated.Results: we obtained responses from 85 of 108 NHS staff (78.7% response rate). At least 6% (n = 10) of the 168 English NHS Trusts have already implemented ePrescribing systems, 2% (n = 4) have no plans of implementing, and 34% (n = 55) are planning to implement with intended rapid implementation timelines driven by high expectations surrounding improved safety and efficiency of care. The majority are unclear as to which system to choose, but integration with existing systems and sophisticated decision support functionality are important decisive factors. Participants highlighted the need for increased guidance in relation to implementation strategy, system choice and standards, as well as the need for top-level management support to adequately resource the project. Although some early benefits were reported by hospitals that had already implemented, the hoped for benefits relating to improved efficiency and cost-savings remain elusive due to a lack of system maturity.Conclusions: whilst few have begun implementation, there is considerable interest in ePrescribing systems with ambitious timelines amongst those hospitals that are planning implementations. In order to ensure maximum chances of realising benefits, there is a need for increased guidance in relation to implementation strategy, system choice and standards, as well as increased financial resources to fund local activitie

    Thrombocytopenic, thromboembolic and haemorrhagic events following second dose with BNT162b2 and ChAdOx1: self-controlled case series analysis of the English national sentinel cohort

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    Thrombosis associated with thrombocytopenia was a matter of concern post first and second doses of BNT162b2 and ChAdOx1 COVID-19 vaccines. Therefore, it is important to investigate the risk of thrombocytopenic, thromboembolic and haemorrhagic events following a second dose of BNT162b2 and ChAdOx1 COVID-19 vaccines. We conducted a large-scale self-controlled case series analysis, using routine primary care data linked to hospital data, among 12.3 million individuals (16 years old and above) in England. We used the nationally representative Oxford-Royal College of General Practitioners (RCGP) sentinel network database with baseline and risk periods between 8th December 2020 and 11th June 2022. We included individuals who received two vaccine (primary) doses of the BNT162b2 mRNA (Pfizer-BioNTech) and two vaccine doses of ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines in our analyses. We carried out a self-controlled case series (SCCS) analysis for each outcome using a conditional Poisson regression model with an offset for the length of risk period. We reported the incidence rate ratios (IRRs) and 95% confidence intervals (CI) of thrombocytopenic, thromboembolic (including arterial and venous events) and haemorrhagic events, in the period of 0-27 days after receiving a second dose of BNT162b2 or ChAdOx1 vaccines compared to the baseline period (14 or more days prior to first dose, 28 or more days after the second dose and the time between 28 or more days after the first and 14 or more days prior to the second dose). We adjusted for a range of potential confounders, including age, sex, comorbidities and deprivation. Between December 8, 2020 and February 11, 2022, 6,306,306 individuals were vaccinated with two doses of BNT162b2 and 6,046,785 individuals were vaccinated with two doses of ChAdOx1. Compared to the baseline, our analysis show no increased risk of venous thromboembolic events (VTE) for both BNT162b2 (IRR 0.71, 95% CI: 0.65-0.770) and ChAdOx1 (IRR 0.91, 95% CI: 0.84-0.98); and similarly there was no increased risk for cerebral venous sinus thrombosis (CVST) for both BNT162b2 (IRR 0.87, 95% CI: 0.41-1.85) and ChAdOx1 (IRR 1.73, 95% CI: 0.82-3.68). We additionally report no difference in IRR for pulmonary embolus, and deep vein thrombosis, thrombocytopenia, including idiopathic thrombocytopenic purpura (ITP), and haemorrhagic events post second dose for both BNT162b2. Reassuringly, we found no associations between increased risk of thrombocytopenic, thromboembolic and haemorrhagic events post vaccination with second dose for either of these vaccines. Data and Connectivity: COVID-19 Vaccines Pharmacovigilance study

    Comparative effectiveness of less commonly used systemic monotherapies and common combination therapies for moderate to severe psoriasis in the clinical setting.

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    BACKGROUND: The effectiveness of psoriasis therapies in real-world settings remains relatively unknown. OBJECTIVE: We sought to compare the effectiveness of less commonly used systemic therapies and commonly used combination therapies for psoriasis. METHODS: This was a multicenter cross-sectional study of 203 patients with plaque psoriasis receiving less common systemic monotherapy (acitretin, cyclosporine, or infliximab) or common combination therapies (adalimumab, etanercept, or infliximab and methotrexate) compared with 168 patients receiving methotrexate evaluated at 1 of 10 US outpatient dermatology sites participating in the Dermatology Clinical Effectiveness Research Network. RESULTS: In adjusted analyses, patients on acitretin (relative response rate 2.01; 95% confidence interval [CI] 1.18-3.41), infliximab (relative response rate 1.93; 95% CI 1.26-2.98), adalimumab and methotrexate (relative response rate 3.04; 95% CI 2.12-4.36), etanercept and methotrexate (relative response rate 2.22; 95% CI 1.25-3.94), and infliximab and methotrexate (relative response rate 1.72; 95% CI 1.10-2.70) were more likely to have clear or almost clear skin compared with patients on methotrexate. There were no differences among treatments when response rate was defined by health-related quality of life. LIMITATIONS: Single time point assessment may result in overestimation of effectiveness. CONCLUSIONS: The efficacy of therapies in clinical trials may overestimate their effectiveness as used in clinical practice. Although physician-reported relative response rates were different among therapies, absolute differences were small and did not correspond to differences in patient-reported outcomes

    Cytokines as Therapeutic Targets in Rheumatoid Arthritis and Other Inflammatory Diseases

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    The human immune system involves highly complex and coordinated processes in which small proteins named cytokines play a key role. Cytokines have been implicated in the pathogenesis of a number of inflammatory and autoimmune diseases. Cytokines are therefore attractive therapeutic targets in these conditions. Anticytokine therapy for inflammatory diseases became a clinical reality with the introduction of tumor necrosis factor (TNF) inhibitors for the treatment of severe rheumatoid arthritis. Although these therapies have transformed the treatment of patients with severe inflammatory arthritis, there remain significant limiting factors: treatment failure is commonly seen in the clinic; safety concerns remain; there is uncertainty regarding the relevance of immunogenicity; the absence of biomarkers to direct therapy decisions and high drug costs limit availability in some healthcare systems. In this article, we provide an overview of the key efficacy and safety trials for currently approved treatments in rheumatoid arthritis and review the major lessons learned from a decade of use in clinical practice, focusing mainly on anti-TNF and anti–interleukin (IL)-6 agents. We also describe the clinical application of anticytokine therapies for other inflammatory diseases, particularly within the spondyloarthritis spectrum, and highlight differential responses across diseases. Finally, we report on the current state of trials for newer therapeutic targets, focusing mainly on the IL-17 and IL-23 pathways

    A management algorithm for patients with intracranial pressure monitoring: the Seattle International Severe Traumatic Brain Injury Consensus Conference (SIBICC).

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    BACKGROUND: Management algorithms for adult severe traumatic brain injury (sTBI) were omitted in later editions of the Brain Trauma Foundation's sTBI Management Guidelines, as they were not evidence-based. METHODS: We used a Delphi-method-based consensus approach to address management of sTBI patients undergoing intracranial pressure (ICP) monitoring. Forty-two experienced, clinically active sTBI specialists from six continents comprised the panel. Eight surveys iterated queries and comments. An in-person meeting included whole- and small-group discussions and blinded voting. Consensus required 80% agreement. We developed heatmaps based on a traffic-light model where panelists' decision tendencies were the focus of recommendations. RESULTS: We provide comprehensive algorithms for ICP-monitor-based adult sTBI management. Consensus established 18 interventions as fundamental and ten treatments not to be used. We provide a three-tier algorithm for treating elevated ICP. Treatments within a tier are considered empirically equivalent. Higher tiers involve higher risk therapies. Tiers 1, 2, and 3 include 10, 4, and 3 interventions, respectively. We include inter-tier considerations, and recommendations for critical neuroworsening to assist the recognition and treatment of declining patients. Novel elements include guidance for autoregulation-based ICP treatment based on MAP Challenge results, and two heatmaps to guide (1) ICP-monitor removal and (2) consideration of sedation holidays for neurological examination. CONCLUSIONS: Our modern and comprehensive sTBI-management protocol is designed to assist clinicians managing sTBI patients monitored with ICP-monitors alone. Consensus-based (class III evidence), it provides management recommendations based on combined expert opinion. It reflects neither a standard-of-care nor a substitute for thoughtful individualized management
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