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J E Buttery

Publications and source records attributed to J E Buttery.

At least 37 records · Page 2Linked to original sources
PubMed1988

Effect of hematocrit concentration on blood glucose value determined on Glucometer II.

Nineteen patient blood samples each with modified hematocrit concentrations of approximately 20, 30, 40, 50, and 60%, were assayed for their glucose concentration by the Glucometer II. Blood removal from the test strip was by the one- and two-blot techniques. The reference method was the Yellow Springs Instruments (YSI) blood glucose analyzer. Glucometer II results were falsely high for the single blot (13-59%, mean 33%) and double blot (12-41%, mean 19%) at 20% hematocrit and falsely low at 60% hematocrit for the single blot (22-44%, mean 37%) and the double blot (26-49%, mean 43%). At 40-50% hematocrit, Glucometer II and YSI results agreed only for the one-blot technique.

Blood Glucose↗
PubMed1987

The effect of the haematocrit value on the determination of glucose levels by reagent-strip methods.

Twenty-one patients' blood samples, each with modified haematocrit concentrations of about 20%, 30%, 40%, 50% and 60%, were assayed for the presence of glucose by two reagent-strip methods--the Ames Glucometer with BG reagent strips and the Reflolux reflectance meter with BM-test strips. The reference method was the YSI blood glucose analyser. Both Ames and BM systems were found to have good precision. Ames results were falsely high (mean, 15%) at a haematocrit value of 20% and falsely low (mean, 21%) at a haematocrit value of 60%. BM results also overestimated (mean, 4%) and underestimated (mean, 5%) at the corresponding haematocrit levels. The results showed good agreement between Ames and BM methods and the YSI method for normal haematocrit concentrations of 40% to 50%. Clinicians should be aware of inaccuracies in glucose results by test-strip methods in patients with abnormal haematocrit concentrations.

Blood Glucose↗
PubMed1987

Atypical LD isoenzymes with five diffuse bands and evidence for two types of binding.

We describe a plasma LD isoenzyme pattern in which all five bands are unusually diffuse and of retarded mobility, an appearance not previously reported. This was shown to be due to binding to immunoglobulin G from which the enzyme could be displaced by an antiserum to gamma chains. Protein A-Sepharose removed most of the LD activity from plasma but did not dissociate the complex, indicating that the Fab end of the Ig molecule was involved in binding. Antiserum to kappa chains displaced LD5 from the complex but had no effect on the anodal bands. By contrast NAD displaced the anodal isoenzymes but not LD5. We suggest that two types of binding are involved. The LD5 complex appears to represent a true antigen-antibody reaction whereas the binding to the faster isoenzymes does not. We also suggest that immunoprecipitation is more reliable than immunoelectrophoresis or immunodiffusion for demonstrating IgG in such complexes and may be of value in defining the nature of binding.

Aged↗
PubMed1987

Colorimetric measurement of D(-)lactate in plasma.

We describe a method for the direct assay of D(-)lactate in plasma using D(-)lactate dehydrogenase and a color reagent to produce a formazan color measured at 510 nm. This method agrees well with a modified lactate UV end-point method r = 0.998 and the regression equation y = 0.974x + 0.13. The precision for low and high concentrations of D(-)lactate is 4.8% and 3.6% within-batch and 8.9% and 1.7% between-batch. Recoveries average 105% and 98% for D(-)lactate at concentrations of 1 and 5 mmol/L, respectively. The proposed method is inexpensive and suitable for routine and emergency use, and shares reagents used for the assay of L(+)lactate and 3-hydroxybutyrate.

3-Hydroxybutyric Acid↗
PubMed1987

Sensitivity of the direct oxalate oxidase assay of urinary oxalate improved.

The direct colorimetric method for urinary oxalate has been modified to improve its sensitivity. Oxalate is precipitated overnight with calcium chloride and ethanol, the precipitate is redissolved, and the oxalate is measured by use of oxalate oxidase (EC 1.2.3.4), methylbenzothiazolinone hydrazone, and dimethylaniline. The color developed is more intense, analytical recovery averages 102%, and the overall imprecision is less than 5%. To assess the accuracy of the method, we used a gas-chromatography comparison method and control sera. Interference from ascorbate is negligible. The modified method retains its simplicity and is less expensive.

Calcium Chloride↗
PubMed1985

Colorimetric measurement of plasma lactate.

A rapid and simple enzymatic method for plasma lactate is proposed using stable reagents to produce the formazan color. This method agrees well with a reference kit method, r = 0.955 and the regression equation is y = 0.99x + 0.09. The over-all recovery averages 100%, with a precision ranging from 0.6 to 3.3%. No interferences have been shown with the formazan reaction. The proposed method is inexpensive, ideal for batch analyses, and is an attractive method for the busy clinical laboratory.

Adenosine Monophosphate↗