We describe an enzymic quantification of phosphatidylglycerol in amniotic fluid. Phosphatidylglycerol is hydrolyzed in alkali and the resulting glycerol is then enzymatically phosphorylated with adenosine 5'-[gamma-32P]triphosphate to yield glycero[32P]phosphate. After removal of excess [gamma-32P]ATP by charcoal, the radioactivity of the glycerophosphate is measured in a liquid scintillation c...

The thyroid uptake at 20 minutes of intravenously administered Technetium-99(m) ((99m)Tc) was measured in 117 patients with a standard scintillation counter. Patients were divided into three groups on the basis of clinical assessment, four-hour (131)I uptake, triiodothyronine (T-3) resin uptake, and protein-bound iodine measurements.In 31 patients with no evidence of thyroid disease the mean (9...

The aim of the study was to validate a nonradioactive method for relative blood flow measurements in severely injured lungs that avoids labor-intensive tissue processing. The use of fluorescent-labeled microspheres was compared with the standard radiolabeled-microsphere method. In seven sheep, lung injury was established by using oleic acid. Five pairs of radio- and fluorescent-labeled microsph...

The 68Ga generator, obtained from New England Nuclear, Boston MA, USA through the Japan Radioisotope Association, uses 68Ge fixed by tin dioxide (SnO2) and placed in a glass column. This column is connected to inlet and outlet tubes and placed in a small lead casing. The generator activity was measured by an ionization chamber from the top (the top shield was removed for measurements). The elua...

The octapeptide octreotide crystallizes with three peptide molecules and about 20% water in the asymmetric unit, and in many ways possesses diffraction properties similar to those of a 'mini-protein' consisting of 24 amino-acid residues. It diffracts to about 1.0 A but data in the range 1.4-1.0 A are weak. It provides a suitable test of different macromolecular X-ray data-collection techniques,...

We describe an assay for 5-aminolevulinic acid dehydratase (EC4.2.1.24) activity. Radioactive [14Cjporphobilinogen, formed by action of this enzyme on [14CJo-aminolevulinic acid, is purified by passage through an ion-exchange chromatographic column before measurement with a liquid scintillation counter. The radioactive substance in the final solution was identified as solely [14C]porphobilinoge...

The use of radioactively labelled proteins for studying proteolysis is well established (Schneider et al., 1965), as are techniques for radiolabelling proteins, which have been developed mainly for radioimmunassay procedures (Yalow & Berson, 1966). 1311 has been the favoured isotope for such work, although it has a short half-life (8.04 days). "'I has a longer half-life (60 days) and can be eff...

THE use of radio-active dyes in the localization of brain tumours has been described in recent years by various authors. For example, Boyack and others (1948) found that di-iodofluorescein in which the iodine had been rendered radio-active was preferentially taken up by brain-tumour tissue, so that the position of the tumour could be determined by Geiger-counter measurements made from outside t...

A competitive binding assay for serum thyroxine has been automated, with the use of small, reusable Sephadex columns to separate thyroxine from endogenous thyroid-binding globulin and later to separate the bound and free thyroxine. Sixty samples an hour are run through columns, which are held in an aluminum turntable rotated by a fraction collector motor. Reagents and samples are fed to the col...