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Biomedical subjects

C Leiendecker-Foster

Publications and source records attributed to C Leiendecker-Foster.

5 recordsLinked to original sources
PubMed1982

Automated assay for alpha 1-antitrypsin with N-alpha-benzoyl-DL-arginine-p-nitroanilide as trypsin substrate and standardized with p-nitrophenyl-p'-guanidinobenzoate as titrant for trypsin active sites.

alpha 1-Antitrypsin is the most abundant of several serum protease inhibitors. Its deficiency is associated with an increased incidence of emphysema in adults, jaundice in newborns, and childhood cirrhosis. We describe an automated functional assay for the Instrumentation Laboratory's Multistat III Microcentrifugal Analyzer with N-alpha-benzoyl-DL-arginine-p-nitroanilide as trypsin substrate. The assay is standardized in terms of moles of trypsin active sites inhibited per liter of serum, by use of a chromogenic titrant for trypsin active sites, p-nitrophenyl-p'-guanidinobenzoate. The method is rapid, precise, and independent of trypsin supplier, and results correlate well with those by a manual chromogenic and a nephelometric assay.

Adult↗
PubMed1981

Improved simultaneous gas-chromatographic analysis for homovanillic acid and vanillylmandelic acid in urine.

We describe an improved gas-chromatographic method for the simultaneous quantitation of the catecholamine metabolites, homovanillic acid (3-methoxy-4-hydroxyphenylacetic acid) and vanillylmandelic acid (3-methoxy-4-hydroxymandelic acid). Our improvements in the method of Muskiet et al. (Clin. Chem. 23: 863, 1977) include a shorter program time and a longer silylation interval. Recovery and precision data obtained by this improved technique are similar to those of Muskiet et al. Vanillylmandelic acid results (y) were compared with those by the method of Pisano et al. (Clin. Chim. Acta 7: 285, 1962). The relation is expressed by the equation y = 0.52 + 1.05x (Sy . x = 2.33 mg/24 h and r = 0.997). Results for homovanillic acid (y) were compared with those by the method of Knight and Haymond (Clin. Chem. 23: 2007, 1977); the equation was y = 0.84 + 0.90x (Sy . x = 2.04 and r = 0.97). Retention times are also reported for several phenolic acids and other related compounds found in urine.

Adolescent↗