24 research outputs found

    Inorganic Mass Spectrometry

    Get PDF
    To establish a method for sensitive, accurate, and precise determination of Se in real samples, isotope dilution analysis using high-power nitrogen microwave-induced plasma mass spectrometry (N 2 MIP-IDMS) was conducted. In this study, freeze-dried human blood serum (Standard Reference Material, NIES No. 4) provided by NIES (National Institute for Environmental Studies) was used as a real sample. The measured isotopes of Se were 78 Se and 80 Se which are the major isotopes of Se. The appropriate amount of a Se spike solution was theoretically calculated by using an error multiplication factor (F) and was confirmed experimentally for the isotope dilution analysis. The mass discrimination effect was corrected for by using a standard Se solution for the measurement of Se isotope ratios in the spiked sample. However, the sensitivity for the detection of Se was not so good and the precision of the determination was not improved (2-3%) by N 2 MIP-IDMS with use of the conventional nebulizer. Therefore, a hydride generation system was connected to N 2 MIP-IDMS as a sample introduction system (HG-N 2 MIP-IDMS) in order to establish a more sensitive detection and a more precise determination of Se. A detection limit (3σ) of 10 pg mL -1 could be achieved, and the RSD was less than 1% at the concentration level of 5.0-10.0 ng mL -1 by HG-N 2 MIP-IDMS. The analytical results were found to be in a good agreement with those obtained by the standard addition method using conventional Ar ICPMS. It is well-known that Se is an essential element for all mammals. Se deficiency leads to deficiency syndromes, for example, Keshan disease, which is known for cardiac insufficiency that occurred in children and pregnant women in China. Problems also occur if the concentration of Se is too high; for example, gastroenteric disorders, dermatitis, and neurotic disorders are caused by excessive intake of Se. Moreover, it is well-known that the range of permissive intake amounts of Se is very narrow for human beings. Therefore, it is restricted as a toxic element in environmental standards. There are several sources of environmental Se pollution: the processes of Se refinement and the production processes of Se-containing products. For these reasons, the accurate and precise determination of trace levels of Se in environmental and biological samples is required, and studies of Se determination have been reported by several groups. [1][2][3][4][5][6][7][8][9][10][11] Because Ar ICPMS can measure multiple elements at a concentration range from ng mL -1 to fg mL -1 , it has widespread use in the determination of trace elements in various samples. 12-25 However

    Methods for estimating costs in patients with hyperlipidemia experiencing their first cardiovascular event in the United Kingdom

    No full text
    <p><b>Aims:</b> Methods for integrating external costs into clinical databases are not well-characterized. The purpose of this research was to describe and implement methods for estimating the cost of hospitalizations, prescriptions, and general practitioner and specialist visits used to manage hyperlipidemia patients experiencing cardiovascular (CV) events in the United Kingdom (UK).</p> <p><b>Methods:</b> This study was a retrospective cohort study using the Clinical Practice Research Datalink and Hospital Episode Statistics data. Costs were incorporated based on reference costs from the National Health Service<b>,</b> and labor costs from the Personal Social Services Research Unit. The study population included patients seen by general practitioners in the UK from 2006<b><i>–</i></b>2012. Patients ≥18 years were selected at the time of their first CV-related hospitalization defined as myocardial infarction, ischemic stroke, heart failure, transient ischemic attack, unstable angina, or revascularization. To be included, patients must have received ≥2 lipid-lowering therapies. Outcome measures included healthcare utilization and direct medical costs for hospitalizations, medications, general practitioner visits, and specialist visits during the 6-month acute period, starting with the CV hospitalization, and during the subsequent 30-month long-term period.</p> <p><b>Results:</b> There were 24,093 patients with a CV hospitalization included in the cohort. This study identified and costed 69,240 hospitalizations, 673,069 GP visits, 32,942 specialist visits, and 2,572,792 prescriptions<b>,</b> representing 855 unique drug and dose combinations. The mean acute period and mean annualized long-term period costs (2014£) were £4<b>,</b>060 and £1<b>,</b>433 for hospitalizations, £377 and £518 for GP visits, £59 and £103 for specialist visits, and £98 and £209 for medications.</p> <p><b>Conclusions:</b> Hospital costs represent the largest portion of acute and long-term costs in this population. Detailed costing using utilization data is feasible and representative of UK clinical practice, but is labor intensive. The availability of a standardized coding system in the UK drug costing data would greatly facilitate drug costing.</p

    Association of a Combined Measure of Adherence and Treatment Intensity With Cardiovascular Outcomes in Patients With Atherosclerosis or Other Cardiovascular Risk Factors Treated With Statins and/or Ezetimibe.

    No full text
    Importance: Both adherence and treatment intensity can alter the effectiveness of lipid-lowering therapy in routine clinical practice. Objective: To evaluate the association of adherence and treatment intensity with cardiovascular outcomes in patients with documented cardiovascular disease (CVD), type 2 diabetes without CVD or chronic kidney disease (CKD), and CKD without CVD. Design, Setting, and Participants: Retrospective cohort study using the Clinical Practice Research Datalink from January 2010 through February 2016. United Kingdom primary care was the setting. Participants were newly treated patients who received their first statin and/or ezetimibe prescription between January 1, 2010, and December 31, 2013, plus an additional prescription for statins and/or ezetimibe during the following year. Exposures: Adherence was assessed annually using the proportion of days covered, with adherent defined as a proportion of days covered of 80% or higher. Treatment intensity was classified according to guidelines based on the expected percentage of low-density lipoprotein cholesterol (LDL-C) reduction as low (<30% reduction), moderate (30% to <50% reduction), or high (≥50% reduction). Adherence and treatment intensity were multiplied to create a combined measure, reflecting treatment intensity after accounting for adherence. Main Outcomes and Measures: Composite end point of cardiovascular death or hospitalization for myocardial infarction, unstable angina, ischemic stroke, heart failure, or revascularization. Hazard ratios (HRs) were estimated against patients not treated for 1 year or longer. Results: Among a total of 29 797 newly treated patients, there were 16 701, 12 422, and 674 patients with documented CVD, type 2 diabetes without CVD or CKD, and CKD without CVD, respectively; mean (SD) ages were 68.3 (13.2), 59.3 (12.4), and 67.3 (15.1) years, and male proportions were 60.6%, 55.0%, and 47.0%. In the documented CVD cohort, patients receiving high-intensity therapy were more likely to be adherent over time (84.1% in year 1 and 72.3% in year 6) than patients receiving low-intensity therapy (57.4% in year 1 and 48.4% in year 6). Using a combined measure of adherence and treatment intensity, a graded association was observed with both LDL-C reduction and CVD outcomes: each 10% increase in the combined measure was associated with a 10% lower risk (HR, 0.90; 95% CI, 0.86-0.94). Adherent patients receiving a high-intensity regimen had the lowest risk (HR, 0.60; 95% CI, 0.54-0.68) vs patients untreated for 1 year or longer. Findings in the other 2 cohorts were similar. Conclusions and Relevance: Results of this study demonstrate that the lowest cardiovascular risk was observed among adherent patients receiving high-intensity therapy, and the highest cardiovascular risk was observed among nonadherent patients receiving low-intensity therapy. Strategies that improve adherence and greater use of intensive therapies could substantially improve cardiovascular risk
    corecore