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N Delaney

Publications and source records attributed to N Delaney.

6 recordsLinked to original sources
PubMed1990

Interpretation of IgG subclass values: a comparison of two assays.

Because we have noted discordant results in the measurement of IgG subclass concentrations by means of a widely available commercial radial immunodiffusion (RID) kit in comparison with an enzyme-linked immunosorbent assay (ELISA) developed at the Centers for Disease Control (CDC), we conducted in a blinded manner a comparison of the two assays, using sera from 48 healthy children. The correlation coefficients between the assays were 0.92, 0.82, 0.93, and 0.86 for the IgG1, IgG2, IgG3, and IgG4 assays, respectively. However, the RID assay assigned lower values for IgG1 and IgG4 determinations than the ELISA did. Furthermore, the "normal lower range values" provided by the RID assay were higher for each IgG subclass. When the sera from the healthy control subjects were analyzed with the RID assay, 12 (25%) of 48 subjects had values below the normal range for at least one subclass measurement. In contrast, with the CDC ELISA, all values were within the 95% confidence limits determined for the CDC ELISA. We suggest that age-specific normal limits be established with the use of sera from many healthy subjects for any assay measuring IgG subclass concentrations. As new groups of immunodeficiencies are defined and potential therapies are advocated, careful attention to assay standardization will result in a clearer delineation of these disease groups and of their response to treatment.

Child↗
PubMed1988

Changes in intestinal calcium transport and binding in magnesium-deficient chicks.

Disruption of membrane integrity and function has been reported previously as one of the predominant effects of magnesium deficiency. In the current study, we have examined the uptake and binding of calcium by intestinal brush border membrane vesicles from chicks and investigated the effects of Mg deficiency on these processes. Both uptake and binding of calcium were significantly decreased in the membrane vesicles from animals given the magnesium-deficient diet. In addition, the calcium-binding activity of proteins isolated by chromatography on DE-52 cellulose of mucosal extracts was altered by the magnesium deficiency.

Animals↗