Objectives: Alpha-tocopherol is the predominant form of vitamin E in plasma and is routinely measured to assess vitamin E status. Agreement between vitamin E assays is essential to provide consistent result interpretation. Lack of agreement among calibrators is potentially a significant obstacle to method harmonization. The aim of this study was to ascertain the agreement between commercial secondary calibrators for analysis of serum/plasma alpha-tocopherol using two methods of isotope dilution liquid chromatography-tandem mass spectrometry (LC-MSMS).
Design And Methods: Three commercial single level calibrators (Bio-Rad Laboratories, Chromsystems Diagnostics and RECIPE) were prepared in quintuplicate in conjunction with an in-house calibrator set for alpha-tocopherol. Samples were analyzed by two methods using an Agilent-6490 LC-MSMS.
Results: The linearity of both methods ranged from at least 4 to 70μmol/L. The expanded within run imprecision of both LC-MSMS methods was ±6% at 95.4% confidence interval across the assay range. The percentage observed difference for the commercial calibrators was calculated from the observed mean against the given value of the calibrator: Bio-Rad (bias +1.4% in both methods); Chromsystems (bias +5.4% [first method] and +5.0% [second method]); and RECIPE (bias -8.9% [first method] and -9.8% [second method]).
Conclusions: Results demonstrate an overall discordance between the commercial calibrators that is greater than the assay uncertainty. It is observed that the greatest deviation of the three calibrators is traceable to a different standard reference material. This lack of harmonization means that results from different laboratories may not be comparable.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.clinbiochem.2013.08.008 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Proposal for a revised Barthel index classification based on mortality risk assessment in functional dependence for basic activities of daily living.
Front Public Health
January 2025
Orcasitas Health Care Center, Madrid, Spain.
Introduction: Functional dependence on the performance of basic activities of daily living (ADLs) is associated with increased mortality. In this study, the Barthel index and its activities discriminate long-term mortality risk, and whether changes in this index are necessary to adapt it to detect mortality risk is examined.
Methods: Longitudinal study, carried out at the Orcasitas Health Center, Madrid (Spain), on the functional dependent population (Barthel ≤ 60).
Nomogram-derived immune-inflammation-nutrition score could act as a novel prognostic indicator for patients with head and neck squamous cell carcinoma.
Front Immunol
January 2025
Department of Otorhinolaryngology Head and Neck Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Aim: This study aims to create and validate a novel systematic immune-inflammation-nutrition (SIIN) score to provide a non-invasive and accurate prognostic tool for head and neck squamous cell carcinoma (HNSCC) patients.
Methods: 259 participants diagnosed with HNSCC from the First Affiliated Hospital of Xi'an Jiaotong University between 2008 and 2017 was included in this retrospective study. Patients were assigned to training (n=181) and validation (n=78) sets.
Advancing presurgical non-invasive spread through air spaces prediction in clinical stage IA lung adenocarcinoma using artificial intelligence and CT signatures.
Front Surg
January 2025
Department of Thoracic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Background: To accurately identify spread through air spaces (STAS) in clinical stage IA lung adenocarcinoma, our study developed a non-invasive and interpretable biomarker combining clinical and radiomics features using preoperative CT.
Methods: The study included a cohort of 1,325 lung adenocarcinoma patients from three centers, which was divided into four groups: a training cohort ( = 930), a testing cohort ( = 238), an external validation 1 cohort ( = 93), and 2 cohort ( = 64). We collected clinical characteristics and semantic features, and extracted radiomics features.
Establishment and validation of a nomogram for coronary artery lesions in children with Kawasaki disease.
Front Cardiovasc Med
January 2025
Clinical Laboratory, Children's Hospital Affiliated to Shandong University, Jinan, China.
Background: The nomogram is a powerful and robust tool in disease risk prediction that summarizes complex variables into a visual model that is interpretable with a quantified risk probability. In the current study, a nomogram was developed to predict the occurrence of coronary artery lesions (CALs) among patients with Kawasaki disease (KD). This is especially valuable in the early identification of the risk of CALs, which will lead to proper diagnosis and treatment to reduce their associated complications.
View Article and Find Full Text PDFValidation of a New Measurement Device (Perikit®) For Perimetry and Volumetry of The Lower Limb: Metrological and Intra-Observer Comparative Study.
Lymphology
January 2025
Medical Oncology Department, UZ Brussel, Brussels, Belgium.
Accurate quantitative assessments are crucial to understanding development of diseases and their effective treatments. Various validated perimetry and volumetry measurement methods for patients with lymphedema exist and each has its own advantages and limitations and choosing the right instrument is essential. PeriKit® (PK) is a new measurement device that requires validation.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!