Search PubMed⌕ Search

Biomedical subjects

W C Butts

Publications and source records attributed to W C Butts.

14 recordsLinked to original sources
PubMed1983

Development and clinical evaluation of a microcentrifugal analyzer method for determining creatine kinase MB isoenzyme.

We have adapted to a microcentrifugal analyzer an immunoinhibition assay for measuring the activity of creatine kinase MB by using an inhibitory antibody for the M monomer. The method actually measures half the MB activity, but results are not multiplied by two because atypical isoenzymes of creatine kinase, including BB, IgG-BB, and the isoenzyme derived from mitochondria, are also detected, if they are present. Results correlated well with an electrophoresis method for 36 serum samples. Myocardial infarction was assessed in 175 patients admitted to our coronary-care unit, with respect to sensitivity (100%) and specificity (98%) when a decision point of 100 U/L (30 degrees C) was chosen for total creatine kinase activity (dithiothreitol-activated) and 6 U/L (30 degrees C) for the isoenzyme (by immunoinhibition). Atypical isoenzymes are easily recognized and confirmed by electrophoresis when the MB activity (by immunoinhibition) exceeds 6 U/L and 20% of the total creatine kinase activity.

Aged↗
PubMed1977

Intra-individual variation in the concentrations of IgA, IgG, IgM, and complement component C3 in serum of a normal adult population.

A recent study [Clin. Chem. 22, 1635 (1976)] reported intra-individual variation in 10 serum proteins to be much smaller than interindividual variation. We report results of a similar study involving about 700 apparently healthy adults in whom we estimated the relative magnitude of the intra- and interindividual variation in serum IgA, IgG, IgM and complement component C3. Specimens were collected from each subject weekly for as long as 10 weeks (average, four weeks). The four serum proteins were quantitated by radial immunodiffusion by the maximal-diffusion technique. Traditional 95% reference intervals were computed relative to WHO reference preparations for the immunoglobulins. For C3, the reference interval was computed relative to a commercial reference preparation. We, too, found the ratios of intra-individual to interindividual variation for adults to be so small that the traditional reference intervals do not have the assumed diagnostic sensitivities. Furthermore, these ratios did not change after dividing the study population into subgroups according to sex and age; evidently such subgrouping do not improve the diagnostic sensitivity. The relatively small intra-individual variations were also observed at the extremes of protein concentration ranges.

Adolescent↗
PubMed1975

Centrifugal analyzer determination of ascorbate in serum or urine with Fe3+/Ferrozine.

Measurement of serum ascorbate may be useful in long-term population studies because of the possible influence of ascorbate on numerous physiological factors. We describe an automated method for determining ascorbate in serum and urine by using the reduction of ferric iron by ascorbate and the formation of a color between the resulting ferrous iron and Ferrozine [3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine]. A centrifugal analyzer is used to rapidly and simultaneously measure ascorbate in the samples and standards and minimize interference from slower reacting substances in the sample. The method is highly precise and specific. Data are also presented on the stability of ascorbate in serum, urine, and aqueous solutions.

Adult↗