Reference interval for glycated haemoglobin in a Montevideo population using a spectrophotometric assay, and comparison with a chromatographic method

Background To clarify the relationship between glycated haemoglobin and glycated albumin concentrations during pregnancy with neonatal outcomes, a multicentre study was conducted by the Japanese Society of Diabetes and Pregnancy. Methods A total of 136 patients (type 1: n = 47, type 2: n = 89) who enrolled in the study were diagnosed based on the Japanese Diabetes Society diagnostic criteria for diabetes mellitus. Thresholds for glycated haemoglobin and glycated albumin were set at 5.8% and 15.8%, respectively, as the upper limits of the reference interval in pregnant women. Result Random plasma glucose decreased linearly, and reached the reference interval at 40 weeks. Glycated albumin concentrations also decreased in the same manner. But glycated haemoglobin concentrations were out of the reference interval during the study. The frequency of the neonatal complications did not show significant differences between the glycated haemoglobin ⩾5.8% group and the glycated haemoglobin <5.8% group. On the other hand, the frequency of neonatal complications showed higher tendency of neonatal complications in the incidence of polycythaemia ( P = 0.094) and heavy-for-date ( P = 0.071) in the glycated albumin ⩾15.8% group compared with the glycated albumin <15.8 group. The respiratory disorder in type 1 diabetes was significantly higher than type 2 diabetes. Conclusions For the treatment of pregnant women with diabetes, glycated albumin would be a better marker than glycated haemoglobin. However, glycated albumin is also affected by obesity and albumin, and it is desirable to make a comprehensive judgment with glycated haemoglobin, random plasma glucose and other glycaemic index.

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Effect of Different Anti-Coagulants on the Accuracy of Glycated Haemoglobin Results

Asian Journal of Medicine and Health ◽

10.9734/ajmah/2019/v16i430152 ◽

2019 ◽

pp. 1-5

Author(s):

Frederick Igila Allison ◽

Duru Ugochukwu Stephen

Keyword(s):

Blood Sample ◽

Sampling Method ◽

Chromatographic Method ◽

Glycated Haemoglobin ◽

Good Stability ◽

Assay Method ◽

Sample Collection ◽

Mean Values ◽

The Third ◽

The Mean

Background: Most manufacturers of glycated haemoglobin kits advocate for the use of EDTA bottles for sample collection. Other manufacturers even when using the same glycated haemoglobin assay method, advocate for the use of any of these anticoagulant: EDTA, heparin and fluoride oxalate as any of these anticoagulants for sample collection. Aim: This study was therefore designed to evaluate the effect of different anticoagulants on the accuracy of glycated haemoglobin value using the same method. Methods: Thirty subjects were selected by purposive sampling method and 2ml of blood was collected from each subject into sodium heparin, EDTA and fluoride oxalate bottles and stored for three days at 4ºC. Fifteen subjects’ samples were analysed daily for the next two days then all the samples were analysed on the third day. All samples were analysed using the boronate affinity chromatographic method by Clover. Results: The mean of the values of glycated haemoglobin of samples for each anticoagulants were about the same for the first, second and third day. The differences in the mean values for each anticoagulant were not statistically significant, indicating fairly good stability. Conclusion: From this study, it could be concluded that blood sample in EDTA, fluoride oxalate and heparin bottles can be used for glycated haemoglobin estimation without affecting the accuracy of the result. These samples in these containers were found to be stable for at least three days.

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Comparison of metabolic fluxes of cis-5-enoyl-CoA and saturated acyl-CoA through the β-oxidation pathway

Biochemical Journal ◽

10.1042/bj3070023 ◽

1995 ◽

Vol 307 (1) ◽

pp. 23-28 ◽

Cited By ~ 2

Author(s):

K Y Tserng ◽

L S Chen ◽

S J Jin

Keyword(s):

Stable Isotope ◽

Rat Liver ◽

Chromatographic Method ◽

Spectrophotometric Assay ◽

Beta Oxidation ◽

Metabolic Fluxes ◽

Hydroxyacyl Coa Dehydrogenase ◽

Acyl Coa Oxidase ◽

Acyl Coa Dehydrogenases ◽

Gas Chromatographic Method

The metabolic fluxes of cis-5-enoyl-CoAs through the beta-oxidation cycle were studied in solubilized rat liver mitochondrial samples and compared with saturated acyl-CoAs of equal chain length. These studies were accomplished using either spectrophotometric assay of enzyme activities and/or the analysis of metabolites and precursors using a gas chromatographic method after conversion of CoA esters into their free acids. Cis-5-enoyl-CoAs were dehydrogenated by acyl-CoA oxidase or acyl-CoA dehydrogenases at significantly lower rates (10-44%) than saturated acyl-CoAs. However, enoyl-CoA hydratase hydrated trans-2-cis-5-enoyl-CoA at a faster rate (at least 1.5-fold) than trans-2-enoyl-CoA. The combined activities of 3-hydroxyacyl-CoA dehydrogenase and 3-ketoacyl-CoA thiolase for 3-hydroxy-cis-5-enoyl-CoAs derived from cis-5-enoyl-CoAs were less than 40% of the activity for the corresponding 3-hydroxyacyl-CoAs prepared from saturated acyl-CoAs. Rat liver mitochondrial beta-oxidation enzymes were capable of metabolizing cis-5-enoyl-CoA via one cycle of beta-oxidation to cis-3-enoyl-CoA with two less carbons. However, the overall rates of one cycle of beta-oxidation, as determined with stable-isotope-labelled tracer, was only 15-25%, for cis-5-enoyl-CoA, of that for saturated acyl-CoA. In the presence of NADPH, the metabolism of cis-5-enoyl-CoAs was switched to the reduction pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

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Reference Interval of Glycated Hemoglobin in Adults in Port Harcourt, Nigeria

Asian Journal of Medicine and Health ◽

10.9734/ajmah/2019/v16i430148 ◽

2019 ◽

pp. 1-6

Author(s):

Allison Frederick Igila ◽

C. Ojule Aaron

Keyword(s):

Reference Interval ◽

Glycated Haemoglobin ◽

Reference Intervals ◽

Resource Poor Setting ◽

Cross Sectional ◽

Port Harcourt ◽

Background Measurement ◽

Local Reference ◽

The Mean ◽

Rivers State

Background: Measurement of glycated haemoglobin is accepted as the gold standard for the diagnosis and management of diabetes mellitus; but it is rarely used in this environment, a resource-poor setting, largely due to the high cost of the assay. There is need to determine its reference intervals in Port-Harcourt and encourage the use of this assay. Aim:This study was designed to determine the reference interval of glycated haemoglobin of apparently healthy subjects between the ages of 20-80 years in Port Harcourt, Rivers State, Nigeria. Methods: A total of 172 subjects who met the inclusion criteria were recruited for the study. A cross sectional sampling method was used to recruit subject. Subjects’ past medical history, demographic and anthropometric information were obtained with the help of a questionnaire. Blood was collected from subjects into an EDTA bottle and analysed for glycated haemoglobin using the boronate affinity chromatographic method. Results: Results were analyzed using Statistical Package for Social Sciences version 20.0 (SPSS 20.0) and the reference interval was determined by the nonparametric method due to the skewness of the data. The mean age of subjects was 35.4 years and the minimum and maximum glycated haemoglobin value obtained were 3.5% and 6.0% after eliminating outliers. This gave a mean glycated haemoglobin value of 4.84% and a reference interval of 4.0-5.9%. Conclusion: The reference interval so determined (4.0-5.9%) is different from that generated by the manufacturer of the diagnostic kit(4.0-6.5%). The introduction of this new local reference interval will enhance patient management in our local hospitals.

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Colorimetric method for free fatty acids in serum validated by comparison with gas chromatography.

Clinical Chemistry ◽

10.1093/clinchem/27.6.924 ◽

1981 ◽

Vol 27 (6) ◽

pp. 924-926 ◽

Cited By ~ 33

Author(s):

S D Brunk ◽

J R Swanson

Keyword(s):

Fatty Acids ◽

Free Fatty Acids ◽

Neonatal Intensive Care ◽

Chromatographic Method ◽

Colorimetric Assay ◽

Colorimetric Method ◽

Reference Interval ◽

Standard Curve ◽

Liquid Chromatographic Method ◽

Liquid Chromatographic

Abstract We compared results by a simplified colorimetric copper-soap method for serum free fatty acids (Clin, Chem. 19: 419, 1973, modified) with those by a gas--liquid chromatographic method. The modified method requires only 100 microliters of sample, its standard curve is linear from 0.1 to 4.0 mmol/L (reference interval for adults: 0.2 to 0.8 mmol/L), and it is suitable for use with newborns. Comparison with the gas--liquid chromatographic method (n = 51) over a wide concentration range gave a correlation coefficient of 0.989. Between-run CVs varied from 4 to 10%, analytical recoveries from 97 to 104%. Triglycerides, salicylates, hemoglobin, and anticoagulants (except citrate) do not interfere, but bilirubin and phospholipids give small positive interferences. The colorimetric assay is used, along with other routine tests, to assess lipid status and estimate kernicterus risk in neonatal intensive-care patients receiving lipid nutrition parenterally.

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