Evaluation of a model of latent pathologic factors in relation to serum ferritin elevation.

Objectives: Serum ferritin increases in various disorders and clinical conditions. However, causal associations between the serum ferritin level and clinical factors that influence serum ferritin level are not well characterized. We report a model that quantitatively analyzes the causal relations between the serum ferritin level and clinical factors.

New enzymatic assay for serum urea nitrogen using urea amidolyase.

We established an enzymatic assay for measurement of serum urea nitrogen using urea amidolyase (EC 3.5.1.

Enzymatic assay for determination of bicarbonate ion in plasma using urea amidolyase.

Background: One of the important buffering systems to maintain blood pH is carbonic acid-bicarbonate. Together with other clinical tests, the measurement of bicarbonate ion concentrations is widely used for the diagnosis of the acid-base balance. We developed a kinetic assay for measurement of bicarbonate ion in plasma using urea amidolyase (EC 3.

Relation between iron content of serum ferritin and clinical status factors extracted by factor analysis in patients with hyperferritinemia.

Objectives: The aims of this study were to develop a new technique for determination of iron content of serum ferritin (ICF, micromol Fe/mg protein) and to investigate relations between ICF and clinical status in patients with hyperferritinemia.

Methods: ICF values were determined by a combination of immunoprecipitation of ferritin and direct colorimetric iron assay. One hundred fifty patients with hyperferritinemia were screened.

Modification of fully automated total iron-binding capacity (TIBC) assay in serum and comparison with dimension TIBC method.

Background: We previously reported the development of a fully automated assay for total iron-binding capacity (TIBC) in serum, using a multipurpose automated analyzer. However, this method requires four different reagents and is thus useful only with a limited number of available analyzers. We simplified our original assay and compared the analytical performance of the modified method with that of a commercial, fully automated TIBC assay (Dimension TIBC assay).