Search results for "reference standards"

A global baseline for ecosystem recovery

2016

Antimicrobial photodynamic therapy using diode laser activated indocyanine green as an adjunct in the treatment of chronic periodontitis: A randomize…

2016

Abstract Introduction Clinical studies have shown the usefulness of antimicrobial photodynamic therapy (aPDT) as an adjunctive in periodontal therapy. These studies did not utilize indocyanine green (ICG) as a recently introduced photosensitizer. The aim of this study was to perform a full-mouth double-blind randomized controlled clinical study to test the efficacy of adjunctive aPDT with ICG compared with scaling and root planing (SRP) alone in chronic periodontitis treatment. Materials and methods Fifty patients were selected for this study. All patients received SRP. Then, each patient was randomly assigned to either the test group (aPDT + SRP) or the control group (SRP). aPDT was perfor…

Standardization of Light Transmission Aggregometry for Diagnosis of Platelet Disorders: An Inter-Laboratory External Quality Assessment.

2019

AbstractSeveral in vitro platelet function tests are available for the diagnosis of inherited platelet function disorders. Currently, the light transmission aggregometry (LTA) is recommended as one of the first-step tests. LTA is available in most specialized hemostasis laboratories. Although the LTA is accepted as a ‘gold standard’ assay for the evaluation of platelet function, its standardization in the clinical practice is still challenging. The GTH-based THROMKID-Plus Study Group has performed an inter-laboratory trial in Germany and Austria. Five different agonists were selected according to the Scientific and Standardization Committee/International Society on Thrombosis and Haemostasi…

An International Proficiency Study with the Tumor Marker CA 125

1990

A strict and adequate quality assurance program is the only real guarantee of the reliability of laboratory test results. Such proficiency testing was carried out for the CA 125 test system in five university laboratories over a period of three years (1984 - 1987) using five different reference materials (BIOREF, FRG). A concentration-dependent performance profile could thus be established evaluating a total of 301 assays. Intra-assay precision of the test ranged between 4.8 and 11.5%, and interassay precision between 13.6 and 19.1%. Laboratory specific average values of the individual reference materials ranged between 26 and 32 U/ml for reference 1, 51 and 59 U/ml for reference 2, 109 an…

International descriptive and interventional survey for oxycholesterol determination by gas- and liquid-chromatographic methods

2018

International audience; Increasing numbers of laboratories develop new methods based on gas-liquid and high-performance liquid chromatography to determine serum concentrations of oxygenated cholesterol metabolites such as 7alpha-, 24(S)-, and 27-hydroxycholesterol. We initiated a first international descriptive oxycholesterol (OCS) survey in 2013 and a second interventional survey 2014 in order to compare levels of OCS reported by different laboratories and to define possible sources of analytical errors. In 2013 a set of two lyophilized serum pools (A and B) was sent to nine laboratories in different countries for OCS measurement utilizing their own standard stock solutions. In 2014 eleven…

A multicentric study to evaluate the use of relative retention times in targeted proteomics.

2016

Despite the maturity reached by targeted proteomic strategies, reliable and standardized protocols are urgently needed to enhance reproducibility among different laboratories and analytical platforms, facilitating a more widespread use in biomedical research. To achieve this goal, the use of dimensionless relative retention times (iRT), defined on the basis of peptide standard retention times (RT), has lately emerged as a powerful tool. The robustness, reproducibility and utility of this strategy were examined for the first time in a multicentric setting, involving 28 laboratories that included 24 of the Spanish network of proteomics laboratories (ProteoRed-ISCIII). According to the results…

Toxicity reduction of ochratoxin A by lactic acid bacteria.

2017

Abstract Ochratoxin A (OTA) is a mycotoxin produced by the metabolism of fungus belonging to the genus Aspergillus and Penicillium. In this paper we report, the capacity of different cultures of lactic acid bacteria (LAB) to degrade OTA present in MRS broth at both pH 3.5 and 6.5. A study of OTA reduction during gastrointestinal digestion carried out with the LAB was also performed. Taking into account the two reduction mechanisms of OTA studied in this work as the enzymatic one and the adsorption on the cell wall, as well as at pH 3.5 and 6.5 the reduction values of OTA were in a range of 30–99%, being the strains with greater reduction (97% and 95%) Lb. rhamnosus CECT 278T and Lb. plantar…

Proteomics Standards Initiative: Fifteen Years of Progress and Future Work.

2017

Abstract: The Proteomics Standards Initiative (PSI) of the Human Proteome Organization (HUPO) has now been developing and promoting open community standards and software tools in the field of proteomics for 15 years. Under the guidance of the chair, co-chairs, and other leadership positions, the PSI working groups are tasked with the development and maintenance of community standards via special workshops and ongoing work. Among the existing, ratified standards, the PSI working groups continue to update PSI-MI XML, MITAB, mzML, mzIdentML, mzQuantML, mzTab, and the MIAPE (Minimum Information About a Proteomics Experiment) guidelines with the advance of new technologies and techniques. Furthe…

Development of an RNA-based kit for easy generation of TCR-engineered lymphocytes to control T-cell assay performance.

2018

Cell-based assays to monitor antigen-specific T-cell responses are characterized by their high complexity and should be conducted under controlled conditions to lower multiple possible sources of assay variation. However, the lack of standard reagents makes it difficult to directly compare results generated in one lab over time and across institutions. Therefore TCR-engineered reference samples (TERS) that contain a defined number of antigen-specific T cells and continuously deliver stable results are urgently needed. We successfully established a simple and robust TERS technology that constitutes a useful tool to overcome this issue for commonly used T-cell immuno-assays. To enable users t…

Administrative Coding in Electronic Health Care Record‐Based Research of NAFLD: An Expert Panel Consensus Statement

2021

BACKGROUND AND AIMS: Electronic health record (EHR)-based research allows the capture of large amounts of data, which is necessary in nonalcoholic fatty liver disease (NAFLD), where the risk of clinical liver outcomes is generally low. The lack of consensus on which International Classification of Disease (ICD) codes should be used as exposures and outcomes limits comparability and generalizability of results across studies. We aimed to establish consensus among a panel of experts on ICD codes that could become the reference standard and provide guidance around common methodological issues.APPROACH AND RESULTS: Researchers with an interest in EHR-based NAFLD research were invited to collect…