77 research outputs found

    The simultaneous detection of trivalent & hexavalent chromium in exhaled breath condensate: A feasibility study comparing workers and controls

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    The analytical method outlined in this feasibility study has been used to show that trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)) can be detected and measured in exhaled breath condensate (EBC) samples. EBC samples and urine samples were collected from a cohort of 58 workers occupationally exposed to hexavalent chromium compounds and 22 unexposed volunteers (control group). Levels of Cr(III) and Cr(VI) were determined in EBC samples and total chromium levels were determined in urine samples. Pre and post working week samples for both EBC and urine were collected in tandem. Total chromium in urine samples was analysed by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of Cr(III) and Cr(VI) in EBC samples used a hyphenated micro liquid chromatography (μLC) system coupled to an ICP-MS. Separation was achieved using an anion exchange micro-sized column. The results showed that the occupationally exposed workers had significantly higher levels of Cr(III) and Cr(VI) in their EBC samples than the control group, as well as higher levels of total chromium in their urine samples. However, for the exposed workers no significant difference was found between pre and post working week EBC samples for either Cr(III) or Cr(VI). This study has established that Cr(III) and Cr(VI) can simultaneously be detected and measured in 'real' EBC samples and will help in understanding inhalation exposure

    Development of a method for the simultaneous detection of Cr(iii) and Cr(vi) in exhaled breath condensate samples using μLC-ICP-MS

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    The method described in this study is a robust and sensitive method for the simultaneous determination of trivalent and hexavalent chromium (Cr(III) and Cr(VI)) in an exhaled breath condensate (EBC) sample and drinking water proficiency testing material sample. The method uses a hyphenated micro liquid chromatography (mLC) system coupled to inductively coupled plasma mass spectrometry (ICP-MS). The optimised method incorporates a pH adjusted EDTA complexation step to stabilise Cr(VI) and Cr(III). Separation was achieved using an anion exchange micro-sized column. The limits of quantification were 0.040 mg L-1 and 0.013 mg L-1 for Cr(III) and Cr(VI) respectively. EBC is the non-invasive collection of condensate from cooled exhaled breath during regular tidal breathing. We propose that EBC may be a suitable alternative biological matrix to give a more comprehensive picture of exposure to Cr(VI) following an inhalation exposure. This study shows that water samples and EBC samples containing Cr(III) and Cr(VI) can be stored in the fridge (~4 C) for up to 6 weeks when they have been diluted 10 fold with an EDTA solution, and that EBC samples must not be frozen after collection if the integrity of Cr(VI) is to be maintained. This study has demonstrated a practical approach to collecting EBC samples from workers potentially occupationally exposed to hexavalent chromium and that the integrity of the chromium species will be maintained prior to analysis

    The investigation of unexpected arsenic compounds observed in routine biological monitoring urinary speciation analysis

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    This study investigates the identity of two unexpected arsenic species found separately in a number of urine samples sent to the Health and Safety Executive's Health and Safety Laboratory for arsenic speciation (arsenobetaine, AB; arsenite, As3+; arsenate, As5+; monomethylarsonic acid, MMA5+; and dimethylarsinic acid, DMA5+). Micro liquid chromatography coupled to inductively coupled plasma mass spectrometry (μLC-ICP-MS) and electrospray time of flight tandem mass spectrometry (ESI-QqTOF-MS/MS) were used to identify the two arsenic peaks by comparison to several characterized arsenicals: arsenocholine, AC; trimethyl arsine oxide, TMAO; dimethylarsenoacetate, DMAA; dimethylarsenoethanol, DMAE; thio-dimethylarsinate, thio-DMA; thio-dimethylarsenoacetate, thio-DMAA and thio-dimethylarsenoethanol, thio-DMAE. The results from both the ICP-MS and ESI-QqTOF-MS/MS investigations indicate that the unexpected arsenic species termed peak 1 was thio-DMA. While the unexpected arsenic species termed peak 2 has yet to be identified, this investigation shows that it was not AC, TMAO, DMAA, DMAE, thio-DMA, thio-DMAA or thio-DMAE. This study demonstrates the incidence of unexpected arsenic species in both routine and non-routine urine samples from both workers and hospital patients

    937-2 Safety and Efficacy of QW3600 (EchoGen®) in Producing LV Opacification During Stress Echocardiography in Normals

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    QW 3600 (EchoGen®) (EG) is a new ultrasonic contrast agent which produces intense LV cavity and even myocardial opacification following IV injection in animals. However, no data exists regarding the potential of this agent to be used in conjunction with stress echo in humans. Therefore, in 17 normals we compared the results of injecting equal volumes of normal saline and progressive doses of EG: 0.02 cc/kg (5 pts). 0.05cc/kg (4). and 0.1cc/kg (8) during stress echo performed to 85% of maximal heart rate. Echo was performed in apical 4 chamber view, and LV contrast opacification was assessed qualitatively (1 + weak and incomplete, 2+ complete cavity. 3+dense and complete) and by videodensitometry (0.3cm2) region of interest in mid cavity. All subjects tolerated the injections well without adverse events. No significant changes were observed in pulse oximetry, the ECG, or 25 laboratory studies. We analyzed the maximal change (Δ) in systolic (S) and diastolic (D) pressure (mmHg) and heart rate (HR) and peak videointensity (PVI) from baseline to post exertion following the injection of either saline or EG (Table, all p=NS for saline vs EG except PVI)DoseSalineEGΔHRΔSBPΔDBPPVIΔHRΔSBPΔDBPPVI0.0248431813424917280.0537351611434321420.13740191037441962LV opacification was absent with saline, was inconsistent at 0.02 and 0.05cc/kg doses, but was≥ 2+ in all but one 0.1cc/kg administration (mean 2.4). Peak LV videointensity after EG was 62 for 0.1cc/kg. Thus, EchoGen® is a new contrast agent which is well tolerated when used with stress echo in normals and results in complete LV opacification at a dose of 0.1cc/kg. EchoGen® should prove to be a useful adjunct to clinical stress echo

    End stage renal disease and survival in people with diabetes:a national database linkage study

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    © The Author 2014. Published by Oxford University Press on behalf of the Association of Physicians. Funding This work was supported by the Wellcome Trust through the Scottish Health Informatics Programme (SHIP). The SHIP is collaboration between the Universities of Aberdeen, Dundee, Edinburgh, Glasgow and St Andrews and the Information Services Division of National Health Service National Service Scotland. Funding for diabetes register linkage and data extraction was provided by the Chief Scientist’s Office of the Scottish Government. The Scottish Diabetes Research Network receives financial support from National Health Services Research Scotland. The Scottish Renal Registry is funded by the Information Services Division of National Health Service National Services Scotland but relies heavily on the goodwill of the contributing renal units who spent a large amount time working with Scottish Renal Registry staff to ensure that the data held within the register are accurate and complete.Peer reviewedPublisher PD

    Risk of cardiovascular disease and total mortality in adults with type 1 diabetes: Scottish registry linkage study

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    <p>Background: Randomized controlled trials have shown the importance of tight glucose control in type 1 diabetes (T1DM), but few recent studies have evaluated the risk of cardiovascular disease (CVD) and all-cause mortality among adults with T1DM. We evaluated these risks in adults with T1DM compared with the non-diabetic population in a nationwide study from Scotland and examined control of CVD risk factors in those with T1DM.</p> <p>Methods and Findings: The Scottish Care Information-Diabetes Collaboration database was used to identify all people registered with T1DM and aged ≥20 years in 2005–2007 and to provide risk factor data. Major CVD events and deaths were obtained from the national hospital admissions database and death register. The age-adjusted incidence rate ratio (IRR) for CVD and mortality in T1DM (n = 21,789) versus the non-diabetic population (3.96 million) was estimated using Poisson regression. The age-adjusted IRR for first CVD event associated with T1DM versus the non-diabetic population was higher in women (3.0: 95% CI 2.4–3.8, p<0.001) than men (2.3: 2.0–2.7, p<0.001) while the IRR for all-cause mortality associated with T1DM was comparable at 2.6 (2.2–3.0, p<0.001) in men and 2.7 (2.2–3.4, p<0.001) in women. Between 2005–2007, among individuals with T1DM, 34 of 123 deaths among 10,173 who were <40 years and 37 of 907 deaths among 12,739 who were ≥40 years had an underlying cause of death of coma or diabetic ketoacidosis. Among individuals 60–69 years, approximately three extra deaths per 100 per year occurred among men with T1DM (28.51/1,000 person years at risk), and two per 100 per year for women (17.99/1,000 person years at risk). 28% of those with T1DM were current smokers, 13% achieved target HbA1c of <7% and 37% had very poor (≥9%) glycaemic control. Among those aged ≥40, 37% had blood pressures above even conservative targets (≥140/90 mmHg) and 39% of those ≥40 years were not on a statin. Although many of these risk factors were comparable to those previously reported in other developed countries, CVD and mortality rates may not be generalizable to other countries. Limitations included lack of information on the specific insulin therapy used.</p> <p>Conclusions: Although the relative risks for CVD and total mortality associated with T1DM in this population have declined relative to earlier studies, T1DM continues to be associated with higher CVD and death rates than the non-diabetic population. Risk factor management should be improved to further reduce risk but better treatment approaches for achieving good glycaemic control are badly needed.</p&gt

    Use of personalised risk-based screening schedules to optimise workload and sojourn time in screening programmes for diabetic retinopathy:A retrospective cohort study

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    Background: National guidelines in most countries set screening intervals for diabetic retinopathy (DR) that are insufficiently informed by contemporary incidence rates. This has unspecified implications for interval disease risks (IDs) of referable DR, disparities in ID between groups or individuals, time spent in referable state before screening (sojourn time), and workload. We explored the effect of various screening schedules on these outcomes and developed an open-access interactive policy tool informed by contemporary DR incidence rates. Methods and findings: Scottish Diabetic Retinopathy Screening Programme data from 1 January 2007 to 31 December 2016 were linked to diabetes registry data. This yielded 128,606 screening examinations in people with type 1 diabetes (T1D) and 1,384,360 examinations in people with type 2 diabetes (T2D). Among those with T1D, 47% of those without and 44% of those with referable DR were female, mean diabetes duration was 21 and 23 years, respectively, and mean age was 26 and 24 years, respectively. Among those with T2D, 44% of those without and 42% of those with referable DR were female, mean diabetes duration was 9 and 14 years, respectively, and mean age was 58 and 52 years, respectively. Individual probability of developing referable DR was estimated using a generalised linear model and was used to calculate the intervals needed to achieve various IDs across prior grade strata, or at the individual level, and the resultant workload and sojourn time. The current policy in Scotland—screening people with no or mild disease annually and moderate disease every 6 months—yielded large differences in ID by prior grade (13.2%, 3.6%, and 0.6% annually for moderate, mild, and no prior DR strata, respectively, in T1D) and diabetes type (2.4% in T1D and 0.6% in T2D overall). Maintaining these overall risks but equalising risk across prior grade strata would require extremely short intervals in those with moderate DR (1–2 months) and very long intervals in those with no prior DR (35–47 months), with little change in workload or average sojourn time. Changing to intervals of 12, 9, and 3 months in T1D and to 24, 9, and 3 months in T2D for no, mild, and moderate DR strata, respectively, would substantially reduce disparity in ID across strata and between diabetes types whilst reducing workload by 26% and increasing sojourn time by 2.3 months. Including clinical risk factor data gave a small but significant increment in prediction of referable DR beyond grade (increase in C-statistic of 0.013 in T1D and 0.016 in T2D, both p < 0.001). However, using this model to derive personalised intervals did not have substantial workload or sojourn time benefits over stratum-specific intervals. The main limitation is that the results are pertinent only to countries that share broadly similar rates of retinal disease and risk factor distributions to Scotland. Conclusions: Changing current policies could reduce disparities in ID and achieve substantial reductions in workload within the range of IDs likely to be deemed acceptable. Our tool s
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