| 1. |
- Andersson, Annika, et al.
(författare)
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Development of parallel reaction monitoring assays for cerebrospinal fluid proteins associated with Alzheimer's disease
- 2019
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Ingår i: Clinica Chimica Acta. - : Elsevier B.V.. - 0009-8981 .- 1873-3492. ; 494, s. 79-93
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Tidskriftsartikel (refereegranskat)abstract
- Detailed knowledge of protein changes in cerebrospinal fluid (CSF) across healthy and diseased individuals would provide a better understanding of the onset and progression of neurodegenerative disorders. In this study, we selected 20 brain-enriched proteins previously identified in CSF by antibody suspension bead arrays (SBA) to be potentially biomarkers for Alzheimer's disease (AD) and verified these using an orthogonal approach. We examined the same set of 94 CSF samples from patients affected by AD (including preclinical and prodromal), mild cognitive impairment (MCI), non-AD dementia and healthy individuals, which had previously been analyzed by SBA. Twenty-eight parallel reaction monitoring (PRM) assays were developed and 13 of them could be validated for protein quantification. Antibody profiles were verified by PRM. For seven proteins, the antibody profiles were highly correlated with the PRM results (r > 0.7) and GAP43, VCAM1 and PSAP were identified as potential markers of preclinical AD. In conclusion, we demonstrate the usefulness of targeted mass spectrometry as a tool for the orthogonal verification of antibody profiling data, suggesting that these complementary methods can be successfully applied for comprehensive exploration of CSF protein levels in neurodegenerative disorders.
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| 2. |
- Beck, O., et al.
(författare)
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Study of measurement of the alcohol biomarker phosphatidylethanol (PEth) in dried blood spot (DBS) samples and application of a volumetric DBS device
- 2018
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Ingår i: Clinica Chimica Acta. - : Elsevier. - 0009-8981 .- 1873-3492. ; 479, s. 38-42
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Tidskriftsartikel (refereegranskat)abstract
- Phosphatidylethanol (PEth) is a group of phospholipids formed in cell membranes following alcohol consumption. PEth measurement in whole blood samples is established as a specific alcohol biomarker with clinical and medico-legal applications. This study further evaluated the usefulness of dried blood spot (DBS) samples collected on filter paper for PEth measurement. Specimens used were surplus volumes of venous whole blood sent for routine LC–MS/MS quantification of PEth 16:0/18:1, the major PEth homolog. DBS samples were prepared by pipetting blood on Whatman 903 Protein Saver Cards and onto a volumetric DBS device (Capitainer). The imprecision (CV) of the DBS sample amount based on area and weight measurements of spot punches were 23–28%. Investigation of the relationship between blood hematocrit and PEth concentration yielded a linear, positive correlation, and at around 1.0–1.5 μmol/L PEth 16:0/18:1, the PEth concentration increased by ~ 0.1 μmol/L for every 5% increase in hematocrit. There was a close agreement between the PEth concentrations obtained with whole blood samples and the corresponding results using Whatman 903 (PEthDBS = 1.026 PEthWB + 0.013) and volumetric device (PEthDBS = 1.045 PEthWB + 0.016) DBS samples. The CV of PEth quantification in DBS samples at concentrations ≥ 0.05 μmol/L were ≤ 15%. The present results further confirmed the usefulness of DBS samples for PEth measurement.
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| 3. |
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| 4. |
- Eggers, Kai M., et al.
(författare)
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Two-hour diagnostic algorithms for early assessment of patients with acute chest pain - Implications of lowering the cardiac troponin I cut-off to the 97.5th percentile
- 2015
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 445, s. 19-24
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Assessment of patients with suspected non-ST elevation myocardial infarction (NSTEMI) is based on cardiac troponin (cTn) levels with the 99th percentile as cut-off. However, cardiovascular risk starts already at lower troponin concentrations. We therefore, aimed to investigate the utility of 2-hour algorithms using the high-sensitivity cardiac troponin I (hs-cTnI) 97.5th percentile as cut-off which corresponds to the standard URL for most biomarkers. Methods: Hs-cTnI was measured at presentation and 2 h in 1624 chest pain patients. Diagnostic algorithms were developed applying hs-cTnI levels dichotomized at the 99th and 97.5th percentiles combined with hs-cTnI changes and/or ECG findings. Results: The prevalence of NSTEMI was 13.9%. The adjusted odds ratios for 1-year mortality were 2.7(95% CI 1.4-5.1) for the 99th percentile and 3.1 (95% CI 1.6-5.9) for the 97.5th percentile. The best-performing 99th percentile-based algorithms provided a positive predictive value (PPV) of 863% and a negative predictive value (NPV) of 993%. Using 97.5th percentile-based algorithms to define NSTEMI resulted in few reclassifications and yielded similar diagnostic estimates (PPV 85.4%, NPV 99.4%). Conclusion: The hs-cTnI 97.5th percentile integrated into 2-hour algorithms provided high diagnostic estimates and could, due to better prognostic properties serve as an alternative to the 99th percentile.
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| 5. |
- Enocsson, Helena, et al.
(författare)
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Soluble urokinase plasminogen activator receptor : A valuable biomarker in systemic lupus erythematosus?
- 2015
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 444, s. 234-241
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Forskningsöversikt (refereegranskat)abstract
- Systemic lupus erythematosus (SLE) is a potentially severe autoimmune condition with an unpredictable disease course, often with fluctuations in disease activity over time. Long term inflammation and drug-related side-effects may subsequently lead to permanent organ damage, a consequence which is intimately connected to decreased quality of life and mortality. New lupus biomarkers that convey information regarding inflammation and/or organ damage are thus warranted. Today, there is no clinical biomarker that indicates the risk of damage accrual. Herein we highlight the urokinase plasminogen activator receptor (uPAR) and especially its soluble form (suPAR) that besides having biological functions in e.g. proteolysis, cell migration and tissue homeostasis, recently has emerged as a promising biomarker of inflammation and prognosis of several disorders. A strong association between suPAR and organ damage in SLE was recently demonstrated, and preliminary data (presented in this review) suggests the possibility of a predictive value of suPAR blood levels. The involvement of suPAR in the pathogenesis of SLE remains obscure, but its effects in leukocyte recruitment, phagocytic uptake of dying cells (efferocytosis) and complement regulation suggests that the central parts of the SLE pathogenesis could be regulated by suPAR, and vice versa.
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| 6. |
- Fourier, Anthony, et al.
(författare)
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Pre-analytical and analytical factors influencing Alzheimer's disease cerebrospinal fluid biomarker variability.
- 2015
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Ingår i: Clinica chimica acta; international journal of clinical chemistry. - : Elsevier BV. - 1873-3492. ; 449, s. 9-15
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Tidskriftsartikel (refereegranskat)abstract
- A panel of cerebrospinal fluid (CSF) biomarkers including total Tau (t-Tau), phosphorylated Tau protein at residue 181 (p-Tau) and β-amyloid peptides (Aβ42 and Aβ40), is frequently used as an aid in Alzheimer's disease (AD) diagnosis for young patients with cognitive impairment, for predicting prodromal AD in mild cognitive impairment (MCI) subjects, for AD discrimination in atypical clinical phenotypes and for inclusion/exclusion and stratification of patients in clinical trials. Due to variability in absolute levels between laboratories, there is no consensus on medical cut-off value for the CSF AD signature. Thus, for full implementation of this core AD biomarker panel in clinical routine, this issue has to be solved. Variability can be explained both by pre-analytical and analytical factors. For example, the plastic tubes used for CSF collection and storage, the lack of reference material and the variability of the analytical protocols were identified as important sources of variability. The aim of this review is to highlight these pre-analytical and analytical factors and describe efforts done to counteract them in order to establish cut-off values for core CSF AD biomarkers. This review will give the current state of recommendations.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Höglund, Kina, 1976, et al.
(författare)
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Alzheimer's disease - Recent biomarker developments in relation to updated diagnostic criteria.
- 2015
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Ingår i: Clinica chimica acta; international journal of clinical chemistry. - : Elsevier BV. - 1873-3492. ; 449, s. 3-8
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Tidskriftsartikel (refereegranskat)abstract
- Alzheimer's disease (AD) is the most common cause of dementia and is characterized by neuroaxonal and synaptic degeneration accompanied by intraneuronal neurofibrillary tangles and accumulation of extracellular plaques in specific brain regions. These features are reflected in the AD cerebrospinal fluid (CSF) by increased concentrations of total tau (t-tau) and phosphorylated tau (p-tau), together with decreased concentrations of β-amyloid (Aβ42), respectively. In combination, Aβ42, p-tau and t-tau are 85-95% sensitive and specific for AD in both prodromal and dementia stages of the disease and they are now included in the diagnostic research criteria for AD. However, to fully implement these biomarkers into clinical practice, harmonization of data is needed. This work is ongoing through the standardization of analytical procedures between clinical laboratories and the production of reference materials for CSF Aβ42, p-tau and t-tau. To monitor other aspects of AD neuropathology, e.g., synaptic dysfunction and/or to develop markers of progression, identifying novel candidate biomarkers is of great importance. Based on knowledge from the established biomarkers, exemplified by Aβ and its many variants, and emerging data on neurogranin fragments as biomarker candidate(s), a thorough protein characterization in order to fully understand the diagnostic value of a protein is a suggested approach for successful biomarker discovery.
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| 11. |
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| 12. |
- Karefylakis, Christos, 1982-, et al.
(författare)
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Vitamin D C3 epimer in a mid-Swedish region : Analytical measurement and epidemiology
- 2018
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Ingår i: Clinica Chimica Acta. - Amsterdam, Netherlands : Elsevier. - 0009-8981 .- 1873-3492. ; 478, s. 182-187
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Tidskriftsartikel (refereegranskat)abstract
- Background: The discovery of an epimeric form of 25(OH)D3 may complicate the interpretation of vitamin Dstatus. The aim of this study was to examine the prevalence and determinants of 25-hydroxy-3-epi-vitamin D3 (3- epi-25(OH)D3) in a mid-Swedish region and to investigate how the measurement of 3-epi-25(OH)D3 would affect the assessment of vitamin D status using current thresholds.Methods: We conducted a cross-sectional study of 8286 in- and outpatients in primary as well as secondary care settings. Plasma 25(OH)D, 25(OH)D2, 25(OH)D3 and 3-epi-25(OH)D3 were measured using High Pressure Liquid Chromatography – Tandem Mass Spectrometry (HPLC – MS/MS). The relative 3-epi-25(OH)D3 contribution was calculated as a percentage of the total 25(OH)D3. Blood samples were collected between March 2014 and July 2015 providing a seasonal aspect to the results.Results: 3-epi-25(OH)D3was detected in 635 cases (7.7% of all subjects), and the mean concentration was8.4 ± 3.5 nmol/L. 3-epi-25(OH)D3correlated significantly with 25(OH)D3(r =0.38, p < 0.001).A multivariateanalysis among the detected showed that male gender and winter season were independently associatedwith higher 3-epi-25(OH)D3/25(OH)D3percentage ratio (R2=0.044). Infants and children had a significantlyhigher detection rate compared to the reference age category (18–45 years) as well as those who were testedduring the summer season.Conclusions: We report findings from the first epidemiologic study of 3-epi-25(OH)D3 conducted in Sweden, based on a large population sample. 3-epi-25(OH)D3 was detected in 7.7% of the study population and the mean concentration was 8.4 nmol/L. The quantification of 3-epi-25(OH)D3 would not significantly influence the clinical interpretation of vitamin D levels. Additional studies are needed to understand the metabolic pathway and the possible physiological functions of this metabolite.
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| 13. |
- Kuhlmann, Julia, et al.
(författare)
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CSF Aβ1-42 - an excellent but complicated Alzheimer's biomarker - a route to standardisation.
- 2017
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Ingår i: Clinica chimica acta; international journal of clinical chemistry. - : Elsevier BV. - 1873-3492. ; 467, s. 27-33
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Tidskriftsartikel (refereegranskat)abstract
- The 42 amino acid form of amyloid β (Aβ1-42) in cerebrospinal fluid (CSF) has been widely accepted as a central biomarker for Alzheimer's disease. Several immunoassays for CSF Aβ1-42 are commercially available, but can suffer from between laboratory and batch-to-batch variability as well as lack of standardisation across assays. As a consequence, no general cut-off values have been established for a specific context of use (e.g., clinical diagnostics) and selection of individuals for enrolment in clinical trials (patient stratification) remains challenging. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has initiated a working group for CSF proteins (WG-CSF) to facilitate standardisation of CSF Aβ1-42 measurement results. The efforts of the IFCC WG-CSF include the development of certified reference materials (CRMs) and reference measurement procedures (RMPs) for key biomarkers. Two candidate RMPs for quantification of Aβ1-42 in CSF based on liquid chromatography tandem mass spectrometry have been developed and tested in two ring trials. Furthermore, two commutability studies including native CSF pools, artificial CSF and spiked materials have been completed. On the basis of these studies, human CSF pools containing only endogenous Aβ1-42 at three concentrations were selected as the format for future CRMs that are now being processed.
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| 14. |
- Nordenskjöld, Anna M., 1977-, et al.
(författare)
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Unrecognized myocardial infarctions detected by cardiac magnetic resonance imaging are associated with cardiac troponin I levels
- 2016
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Ingår i: Clinica Chimica Acta. - Amsterdam, Netherlands : Elsevier BV. - 0009-8981 .- 1873-3492. ; 455, s. 189-194
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Tidskriftsartikel (refereegranskat)abstract
- Background: Both unrecognized myocardial infarction (UMI) and elevated levels of biomarkers are common in patients with stable coronary artery disease (CAD). The objective of this study was to determine the association between levels of cardiac biomarkers, UMI and extent of CAD in patients with stable CAD.Methods: A total of 235 patients (median age: 65 years; 34% women) with stable CAD without previously known myocardial infarction were examined with late gadolinium enhancement cardiovascular magnetic resonance imaging and coronary angiography. Blood samples were drawn at enrolment and high sensitivity cardiac troponin I (cTnI), NT-proBNP and Galectin-3 were analyzed.Results: UMI was detected in 58 patients (25%). The median levels of cTnI, NT-proBNP and Galectin-3 were significantly higher in patients with UMI compared to those without, (p < 0.001, p = 0.006 and p = 0.033, respectively). After adjustment for cardiovascular risk factors, left ventricular ejection fraction and renal function, cTnI remained independently associated with the presence of UMI (p = 0.031) and the extent of CAD (p = 0.047). Neither NT-proBNP, nor Galectin-3, was independently associated with UMI or extent of CAD.Conclusions: The independent association between levels of cTnI and UMI indicates a common pathophysiological pathway for the cTnI elevation and development of UMI.
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| 15. |
- Omland, T, et al.
(författare)
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Troponins in heart failure
- 2015
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Ingår i: Clinica chimica acta. - : Elsevier BV. - 1873-3492 .- 0009-8981. ; 443, s. 78-84
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Tidskriftsartikel (refereegranskat)
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| 16. |
- Petersmann, Astrid, et al.
(författare)
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Impact of physical activity of individuals and creatine kinase on 99th percentiles of troponin I assays
- 2016
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 462, s. 187-192
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Tidskriftsartikel (refereegranskat)abstract
- Determination of cardiac troponin I (cTnI) is one central means for diagnosis of myocardial infarction. Assay performance of three troponin I assays was compared previously in a large reference population detecting sex-differences in the 99th percentile only for the Dimension Vista cTnI assay. The present study examined the underlying effects. Values for cTnI were reused. Creatine kinase (CK) activity was determined in 2358 samples from blood donors. Information on physical activity was evaluated from health questionnaires. Using quantile regression data were analysed to investigate the impact of sex, physical activity, and CK on the 99th percentile of the cTnI assay. We report significant sex-differences for the 99th percentile of cTnI. Physical activity was significantly associated with cTnI values. Strong association of CK activity with cTnI values was detected only in men. Adjustment for CK in quantile regression abolished sex -differences in the 99th percentile. Two other contemporary sensitive cTnI assays were not relevantly affected by physical activity or CK. Sex -differences in the 99th percentile for the Dimension Vista cTnI assay arise from a positive association between cTnI and physical activity and were abrogated when data were adjusted for CK activity. These findings should be taken into account when using this assay.
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| 17. |
- Ravn, Bo, et al.
(författare)
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Intra-day variability of cystatin C, creatinine and estimated GFR in intensive care patients
- 2016
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 460, s. 1-4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Markers of renal function are widely used in intensive care and sudden changes are important indicators of acute kidney injury. The problem is to distinguish between disease progression/improvement from the natural variation in the patient. The aim of the present study was thus to study the normal intraday variation in ICU patients.METHODS: We studied the intra-day variation of creatinine, cystatin C and estimated GFR based on these two markers in 28 clinically stable ICU patients.RESULTS: The median diurnal coefficient of variation sCV) for creatinine was 3.70% (1.92-9.25%) while the median CV for cystatin C was 3.66% (1.36-8.11%). The corresponding CVs for the estimated GFRs were 2.00% (0.89-9.82%) for eGFRcreatinine and 4.60% (1.65-10.24%) for eGFRcystc.CONCLUSIONS: The eGFRcreatinine values in individual patients were clearly higher than the eGFRcystc values. The median CV for creatinine, cystatin C and the eGFR measurements were below 5% which means that 95% of the test results will vary by <10% between sampling times in stable ICU patients. Differences >10% between sampling times are thus likely to be an indication of changes in biomarker levels due to the disease/treatment.
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| 18. |
- Resendez, Angel, et al.
(författare)
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Rapid small intestinal permeability assay based on riboflavin and lactulose detected by bis-boronic acid appended benzyl viologens
- 2015
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 439, s. 115-121
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Although organoboronic acids are efficient high-throughput sugar sensors, they have not been pursued for gut permeability studies. A modification of the lactulose/mannitol assay is described by which small intestinal permeability is assessed at the time of urine collection using a lactulose/riboflavin ratio.METHODS: Volunteers ingested 50mg riboflavin and either 5g mannitol or 10g lactulose. Urine was collected for 6hrs. Riboflavin was assayed by autofluorescence. Riboflavin was removed by C18 solid phase extraction. Lactulose and mannitol were then assayed using 1,1'-bis(2-boronobenzyl)-4,4'-bipyridinium (4,4'oBBV) coupled to the fluorophore HPTS.RESULTS: The temporal profile over 6hrs for riboflavin paralleled mannitol. Riboflavin recovery in urine was 11.1±1.9 % (mean±SEM, n=7), similar to mannitol. There was selective binding of 4,4'oBBV to lactulose, likely involving cooperativity between the fructose and galactose moieties. Lower limits of detection and quantification were 90 and 364μM. The lactulose assay was insensitive to other permeability probes (e.g., sucrose, sucralose) while tolerating glucose or lactose. This assay can be adapted to automated systems. Stability of 4,4'oBBV exceeds 4years.CONCLUSIONS: Riboflavin measured by autofluorescence combined with lactulose measured with 4,4'oBBV represents a useful new chemistry for rapid measurement of intestinal permeability with excellent stability, cost and throughput benefits.
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| 19. |
- Ronquist, Göran
(författare)
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Extracellular vesicles and energy metabolism
- 2019
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981 .- 1873-3492. ; 488, s. 116-121
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Forskningsöversikt (refereegranskat)abstract
- Glycolytic enzymes are among the most frequently identified proteins in proteomics of exosomes/extracellular vesicles. This review brings up the possibility that exosomes/extracellular vesicles during their life-time in bodily fluids power important energy-consuming functions by glycolytic conversion of glucose or fructose into ATP. It was seen that prostasomes (exosomes of the prostate) could produce ATP by glycolysis and that the produced ATP quickly was consumed by adjacent prostasomal ATPases. The glycolytic ATP production appeared to be coupled to self-sustaining energy requirements. It will also be discussed how a failure in this machinery (lowered activity of ATPases) with a resultant polluting leakage of extracellular ATP could affect cancer development.
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| 20. |
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| 21. |
- Shamoun, Levar, et al.
(författare)
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Association study on IL-4, IL-4Rα and IL-13 genetic polymorphisms in Swedish patients with colorectal cancer
- 2018
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Ingår i: Clinica Chimica Acta. - : Elsevier. - 0009-8981 .- 1873-3492. ; 487, s. 101-106
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Interleukin 4 (IL-4) and interleukin 13 (IL-13) are anti-inflammatory and immunomodulatory cytokines which share a common cellular receptor IL4Rα and are involved in the same signaling pathways. Our purpose was to assess whether genetic variants within IL-4, IL-13 and IL-4Rα are associated with the risk or clinical outcome of colorectal cancer (CRC).METHODS: Three single nucleotide polymorphisms (SNPs) were screened in 466 patients with CRC and 445 healthy controls. The selected SNPs were IL-4 SNP rs2243250, IL-4Rα SNP rs1801275 and IL-13 SNP rs1800925.RESULTS: We found that the genotype variant T/T in IL-13 gene was associated with a higher risk of CRC. Kaplan-Meier analysis showed that the cancer specific survival differed between C/C and CT + TT for IL-4 SNP. Moreover, the carriers of the T allele were associated with the highest risk of CRC death with a hazard ratio (HR) of 1.57, 95% CI 1.06-2.36, p = .024. The observed effect of the T allele was restricted to stage III patients.CONCLUSION: Our results indicate IL-13 SNP rs1800925 as a risk factor for CRC and that IL-4 SNP rs2243250 could be a useful prognostic marker in the follow-up and clinical management of patients with CRC especially in stage III disease.
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| 22. |
- Thornton, Claire, et al.
(författare)
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Role of mitochondria in apoptotic and necroptotic cell death in the developing brain.
- 2015
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Ingår i: Clinica chimica acta; international journal of clinical chemistry. - : Elsevier BV. - 1873-3492. ; 451:Part: A Special Issue: SI, s. 35-38
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Tidskriftsartikel (refereegranskat)abstract
- Hypoxic-ischemic encephalopathy induces secondary brain injury characterized by delayed energy failure. Currently, therapeutic hypothermia is the sole treatment available after severe intrapartum asphyxia in babies and acts to attenuate secondary loss of high energy phosphates improving both short- and long-term outcome. In order to develop the next generation of neuroprotective therapies, we urgently need to understand the underlying molecular mechanisms leading to cell death. Hypoxia-ischemia creates a toxic intracellular environment including accumulation of reactive oxygen/nitrosative species and intracellular calcium after the insult, inducing mitochondrial impairment. More specifically mitochondrial respiration is suppressed and calcium signaling is dysregulated. At a certain threshold, Bax-dependent mitochondrial permeabilization will occur leading to activation of caspase-dependent and apoptosis-inducing factor-dependent apoptotic cell death. In addition, hypoxia-ischemia induces inflammation, which leads to the release of TNF-α, TRAIL, TWEAK, FasL and Toll-like receptor agonists that will activate death receptors on neurons and oligodendroglia. Death receptors trigger apoptotic death via caspase-8 and necroptotic cell death through formation of the necrosome (composed of RIP1, RIP3 and MLKL), both of which converge at the mitochondria.
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| 23. |
- Venge, Per, et al.
(författare)
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Equal clinical performance of a novel point-of-care cardiac troponin I (cTnI) assay with a commonly used high-sensitivity cTnI assay
- 2017
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Ingår i: Clinica Chimica Acta. - : ELSEVIER SCIENCE BV. - 0009-8981 .- 1873-3492. ; 469, s. 119-125
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Tidskriftsartikel (refereegranskat)abstract
- Background: Efficient rule-out of acute myocardial infarction (MI) facilitates early disposition of chest pain patients in emergency departments (ED). Point-of-care (POC) cardiac troponin (cTn) may improve patient throughput. We compared the diagnostic accuracy of a novel cTnI test (Minicare cTnI, Philips), with current POC cTnI (I-Stat, Abbott) and high-sensitivity central laboratory cTnI (hs-cTnI; Architect, Abbott) assays.Methods: The clinical performance of the assays were compared in samples from 450 patients from a previous clinical evaluation of Minicare cTnI.Results: Minicare cTnI correlated with Architect hs-cTnI (r(2) = 0.85, p < 0.0001) and I-Stat cTnI (r(2) = 0.93, p < 0.0001). Areas under the receiver operating characteristics curves were 0.87-0.91 at admission (p = ns) and 0.96-0.97 3 h after admission (p = ns). The negative predictive values (NPV) at admission were 95% ((92-97%, 95% CI) for Minicare cTnI and increased to 99% (97-100%) at 2-4 h, and similar to Architect hs-cTnI (98%, 96-100%), but higher than I-Stat cTnI (95%, 92-97%; p < 0.01). Negative likelihood ratios (LR) after 2-4 h were 0.06 (0.02-0.17, 95% CI) for Minicare cTnI, 0.11 (0.05-0.24) for Architect hs-cTnI (p = 0.02) and 0.28 (0.18-0.43) for I-Stat cTnI (p < 0.0001). The clinical concordances between Minicare cTnI and Architect hs-cTnI were 92% (admission) and 95% (2-4 h), with lower concordances between Minicare cTnI and I-Stat cTnI (83% and 78%, respectively; p = 0.007).Conclusions: The Minicare cTnI POC assay may become useful for prompt and safe ruling-out of AMI in ED patients with suspected AMI using a guideline supported 0/3 h sampling protocol.
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| 24. |
- den Bakker, Emil, et al.
(författare)
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Accurate eGFR reporting for children without anthropometric data
- 2017
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981. ; 474, s. 38-43
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Reporting estimated glomerular filtration rate (eGFR) instead of serum concentrations is advised in current guidelines. Most creatinine-based eGFR equations for children require height, a parameter not readily available to laboratories. Combining height-dependent creatinine- and cystatin C-based eGFR improves performance. Recently, a height-independent creatinine-based eGFR equation has been developed. Aim To compare the combination of height-independent creatinine- and cystatin C-based equations with a combination of equations using anthropometric data. Methods Retrospective analysis of 408 pediatric inulin clearance studies with simultaneous height, creatinine, cystatin C and urea measurements. eGFR calculation using the recalibrated Schwartzcrea (height-dependent), FASage (height-independent) and the Schwartzcys equation. The means (Schwartzcrea + Schwartzcys) / 2 and (FASage + Schwartzcys) / 2 were compared with the CKiD3 equation incorporating cystatin C, creatinine, urea, height and gender in terms of %prediction error and accuracy. Results All three single parameter equations performed similarly (P30 accuracy around 80%). (FASage + Schwartzcys) / 2 (P30 89.2%) and (Schwartzcrea + Schwartzcys) / 2 (P30 89.0%), performed comparably to CKiD3 (P30 90.0%). If the difference between the creatinine- and the cystatine C based eGFR was < 40%, P30 accuracy of the mean exceeded 90%. Conclusion Combining the height-independent FASage and SchwartzCys equations substantially improves accuracy and performs comparably to height-dependent equations. This allows laboratories to directly report eGFR in children.
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| 25. |
- Gåfvels, Mats, et al.
(författare)
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A fast semi-quantitative LC-MS method for measurement of intact apolipoprotein A-I reveals novel proteoforms in serum.
- 2015
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Ingår i: Clinica Chimica Acta. - : Elsevier BV. - 0009-8981. ; 442:Jan 17, s. 87-95
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Tidskriftsartikel (refereegranskat)abstract
- Surrogate markers for reverse cholesterol transport (RCT) efficiency such as HDL cholesterol and immune methods for apolipoprotein A-I (ApoA-I) may not fully reflect the actual efficiency of the RCT pathway. Several genetic variants and different posttranslational proteoforms of ApoA-I may unevenly affect the functionality of the HDL particle to efflux cholesterol. A method employing top-down immunoaffinity LC-MS of ApoA-I in order to characterize the most prevalent ApoA-I proteoforms in human plasma is described.
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