scholarly journals Diagnosis of Gestational Diabetes Mellitus with Point-of-Care Methods for Glucose versus Hospital Laboratory Method Using Isotope Dilution Gas Chromatography-Mass Spectrometry as Reference

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Karl Kristensen ◽  
Anne-Marie Wangel ◽  
Anastasia Katsarou ◽  
Nael Shaat ◽  
David Simmons ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Gestational Diabetes ◽  
Gestational Diabetes Mellitus ◽  
Point Of Care ◽  
Gas Chromatography Mass Spectrometry ◽  
Positive Bias ◽  
Altman Analysis ◽  
Bland Altman Analysis

Background. In Sweden, both glucose analyzers in accredited laboratories and point-of-care glucose devices are used for gestational diabetes mellitus (GDM) diagnosis. The aim of this study was to compare the diagnostic performance of the HemoCue Glucose 201+ (HC201+) and RT (HC201RT) systems with that of the hospital central laboratory hexokinase method (CL) based on lyophilized citrate tubes, using the isotope dilution gas chromatography-mass spectrometry (ID GC-MS) as reference. Methods. A 75 g oral glucose tolerance test was performed on 135 women screened positive for GDM. Diagnosis was based on the World Health Organization 2013 diagnostic thresholds for fasting (n=135), 1 h (n=52), and 2 h (n=135) glucose measurements. Bland-Altman analysis and surveillance error grids were used to evaluate analytical and clinical accuracy. Results. Significantly more women were diagnosed with GDM by HC201+ (80%) and CL (80%) than with the reference (65%, P<0.001) based on fasting and/or 2 h thresholds, whereas the percentage diagnosed by HC201RT (60%) did not differ significantly from the reference. In Bland-Altman analysis, a positive bias was observed for HC201+ (4.2%) and CL (6.1%) and a negative bias for HC201RT (−1.8%). In the surveillance error grid, 95.9% of the HC201+ values were in the no-risk zone as compared to 98.1% for HC201RT and 97.5% for CL. Conclusions. A substantial positive bias was found for CL measurements resulting in overdiagnosis of GDM. Our findings suggest better performance of HC201RT than HC201+ in GDM diagnosis. The results may have possible implications for GDM diagnosis in Sweden and require further elucidation.

Urinary metabolites of thromboxane and prostacyclin in diabetes mellitus

1988 ◽  
Vol 118 (2) ◽  
pp. 301-305 ◽  
Author(s):  
K. Gréen ◽  
O. Vesterqvist ◽  
V. Grill
Keyword(s):  
Diabetes Mellitus ◽  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Insulin Treatment ◽  
Artificial Pancreas ◽  
Urinary Metabolites ◽  
Gas Chromatography Mass Spectrometry ◽  
Diabetic State ◽  
In Vivo Synthesis

Abstract. The in vivo synthesis of thromboxane A2 and prostacyclin was estimated in 23 diabetics through measurements of the major urinary metabolites 2,3-dinor-thromboxane B2 and 2,3-dinor-6-keto-PGF1α utilizing gas chromatography-mass spectrometry. Mean excretion was similar to that in non-diabetic subjects. The possible influence of hyperglycemia on the excretion of 2,3-dinor-thromboxane B2 and 2,3-dinor-6-keto-PGF1α was evaluated in three ways: by measuring excretion before and during an acute 9-h normalization of hyperglycemia through an artificial pancreas (Biostator) as well as by comparing excretion before and 7–12 days or 40–180 days after the initiation of insulin treatment. Despite significant reducing effects on hyperglycemia or on levels of hemoglobin A1c, no effects on the excretion of the thromboxane and prostacyclin metabolites could be found. Abnormal formation of thromboxane or prostacyclin is not a generalized feature of the diabetic state.

scholarly journals Development and validation of the method for the detection of glimepiride via derivatization employing N-methyl-N-(trimethylsilyl) trifluoroacetamide using gas chromatography-mass spectrometry

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Priyanka Verma ◽  
Atul Bajaj ◽  
R. M. Tripathi ◽  
Sudhir K. Shukla ◽  
Suman Nagpal
Keyword(s):  
Diabetes Mellitus ◽  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Drug Users ◽  
Coefficient Of Determination ◽  
Gas Chromatography Mass Spectrometry ◽  
Biological Matrices ◽  
Chromatography Mass Spectrometry ◽  
Ms Analysis ◽  
The Stability

Abstract Background Recent advances in the diversified anti-diabetic drugs have appeared in the startling increase in the count of poisoning cases. The epidemics of diabetes mellitus are increasing; hence, the no. of anti-diabetic drug users raised by 42.9%. The use of glimepiride raised to 24%. As the toxicity and drug cases are also escalating with increasing epidemics of diabetes mellitus, a novel gas chromatography-mass spectrometry (GC-MS) method for detecting glimepiride in biological matrices is developed. Results Liquid-liquid extraction method was employed by using 1-butanol: hexane (50:50, v/v) under an alkaline medium, and then back extraction was done via acetic acid. Distinct derivatization techniques were employed for the sample preparation for GC-MS analysis, i.e., silylation and acylation. Derivatization approaches were optimized under different parameters, i.e., reaction temperature and reaction time. N-Methyl-N-(trimethylsilyl) trifluoroacetamide [MSTFA] was found to be the best sound derivatization reagent for the GC-MS analysis of glimepiride. Total ion current (TIC) mode was selected for the monitoring of ions of trimethylsilyl (TMS) derivative of glimepiride with an m/z ratio of 256. Distinct parameters like specificity, carryover, stability, precision, and accuracy were evaluated for validating the identification method. The GC-MS method is found to be linear and illustrated within the range 500 to 2500 ng/ml with the value of R2 (coefficient of determination) at 0.9924. The stability of the extracted and derivatized glimepiride was accessed with regard to processed/extracted sample conditions and autosampler conditions, respectively. Accuracy at each concentration level was within the + 15% of the nominal concentration. Precision (%) for the interday and intraday analysis was found to be in the respectable spectrum. Conclusion Henceforth, the proposed GC-MS method can be employed for the determination of glimepiride in biological matrices.

Determination of Phytosterols in Butter Samples by Using Capillary Column Gas Chromatography

1987 ◽  
Vol 70 (5) ◽  
pp. 912-915 ◽  
Author(s):  
Randall L Smith ◽  
Darryl M Sullivan ◽  
Earl F Richter
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Retention Time ◽  
Capillary Column ◽  
Limit Of Detection ◽  
Packed Column ◽  
Gas Chromatography Mass Spectrometry ◽  
Positive Bias ◽  
Capillary Column Gas Chromatography

Abstract A positive bias in the gas chromatographic (GC) analysis of butter for β-sitosterol was discovered when attempting to confirm values by gas chromatography/mass spectrometry (GC/MS). The source of the problem was traced to an interfering material that was not effectively separated by packed column GC. Because capillary columns are known to provide superior separation, they were substituted for packed columns in the assay, and instrument parameters were modified accordingly. A compound with a similar retention time, identified by GC/MS as lanosterol, was separated from β-sitosterol by the capillary column. The capillary column technique was applied to over 300 butter samples. The results indicate that the method can accurately quantitate β-sitosterol in butter with no known interferences. The limit of detection for this method is 1 mg/100 g. Recoveries at a level of 3 mg/100 g averaged 98% with a coefficient of variation of 3.45%

Quantification of 5 alpha- and 5 beta-androstanediols in urine by gas chromatography-mass spectrometry.

1987 ◽  
Vol 33 (2) ◽  
pp. 256-260 ◽  
Author(s):  
L Muller ◽  
G Phillipou
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Diurnal Rhythm ◽  
Capillary Gas Chromatography ◽  
Internal Standard ◽  
Reference Intervals ◽  
Gas Chromatography Mass Spectrometry ◽  
Positive Bias ◽  
Men And Women ◽  
Chromatography Mass Spectrometry

Abstract We measured concentrations of 5 alpha-androstane-3 alpha,17 beta-diol (Ad) and 5 beta-androstane-3 alpha,17 beta-diol (beta-Ad) in urine by specific capillary gas chromatography-mass spectrometry, with [16,16,17 alpha-2H3]-5 alpha-androstane-3 alpha,17 beta-diol as the internal standard. Comparison of the so-derived reference intervals for Ad and beta-Ad in men and women with those previously published indicates a significant positive bias for many of the previous assays in comparison with our procedure. Both Ad and beta-Ad have a pronounced diurnal rhythm, with maximum excretion in the interval 2300-0700 hours. Concentrations of Ad and beta-Ad were significantly correlated (r = 0.786, p less than 0.001), but the ratio of Ad to beta-Ad was not correlated to that for androsterone to etiocholanolone, the major 5 alpha and 5 beta metabolites of androgens in urine.

scholarly journals A Prospective Evaluation of Point-of-Care Measurements of Maternal Glucose for the Diagnosis of Gestational Diabetes Mellitus

2020 ◽  
Vol 66 (2) ◽  
pp. 316-323 ◽  
Author(s):  
Eimer G O’Malley ◽  
Ciara M E Reynolds ◽  
Ruth O’Kelly ◽  
Anne Killalea ◽  
Sharon R Sheehan ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Regression Analysis ◽  
Gestational Diabetes ◽  
Gestational Diabetes Mellitus ◽  
Plasma Glucose ◽  
Point Of Care ◽  
Oral Glucose ◽  
Regression Equations ◽  
Capillary Glucose ◽  
Maternal Glucose

Abstract Background Point-of-care (POC) measurement of glucose is currently recommended only for the monitoring of gestational diabetes mellitus (GDM). This prospective observational study evaluated the use of POC measurements of maternal glucose to diagnose GDM in women being screened selectively with a 1-step 75 g oral glucose tolerance test (OGTT). Methods The strictest preanalytic and analytic international laboratory standards were applied to measure maternal plasma glucose at fasting and at 1 and 2 h post glucose load. The recent International Association of Diabetes and Pregnancy Study Groups diagnostic criteria were used. At the same time, maternal capillary glucose was measured. Because of differences in plasma and capillary glucose measurements, regression analysis of POC capillary glucose results vs laboratory plasma glucose results was conducted. The regression equations for plasma glucose were derived in a derivation cohort (n = 102). These equations were applied in the validation cohort (n = 100). Predicted and actual plasma glucose values were compared. Results Of the 202 women screened, 36.6% were nulliparous, 56.4% were obese, and 81.2% were Irish-born. Two thirds had a single risk factor for GDM, and a third had multiple risk factors. Based on the plasma measurements, 53.5% had GDM. As a predictor of GDM, the diagnostic accuracy of POC measurement was 83.0% (95% confidence interval, 74.2–89.8). Conclusions In high-resource settings where measures to inhibit glycolysis are implemented, the use of POC measurements for the diagnosis of GDM is not justified based on this study. In low- and medium-resource settings, where measures to inhibit glycolysis are not achievable, regression analysis using POC measurements may be acceptable compared with plasma samples subject to glycolysis.

Sign in / Sign up

Export Citation Format

Share Document