H. Seligson

Measurement of thyroxine by competitive protein binding

Abstract A simplified method is described for the measurement of thyroxine by competitive protein binding, using Sephadex columns for separation of bound from unbound thyroxine. Conditions for the various steps in the method were studied. The results compare well with PBI determinations done on the same subjects.

The isolation of several aromatic acids from the hemodialysis fluids of uremic patients

Abstract The organic acids of five patients with chronic uremia have been investigated, using hemodialysis fluids obtained from these patients. Five acids have been isolated, identified and quantified : hippuric, o- hydroxyhippuric , m- hydroxyhippuric , p- hydroxyhippuric and p- hydroxybenzoic acids. Isolation procedures utilized counter-current distribution, along with paper and column chromatography. Infra-red spectrophotometry and gas chromatography provided absolute identification. It is thought that prolonged retention of these acids or other organic acids may contribute to uremic symptomatology.

Measurement of serum thyroxine-binding capacity

A new method for free thyroxine-binding sites on thyroxine-binding globulin has been described. This method for thyroxine-binding capacity has the virtues of reasonable specificity and convenience for routine use. When used with serum thyroxine levels it should be valuable in the calculation of free thyroxine and total thyroxine-binding globulin. A more directly estimated TBC as reported here should have more value than the various and more empirical T3 uptake methods.

Isolation of N-methyl-2-pyridone-5-carboxamide from hemodialysis fluid obtained from uremic patients☆

N-methyl-2-pyridone-5-carboxamide (2-PY amide) from the hemodialysis fluids of five uremic patients has been isolated, purified, identified and quantified. Ultra-violet and infra-red spectra are presented. The failure of uremic patients to excrete the end products of nicotinic acid derivatives leads to the accumulation of 2-PY amide in uremic blood. This small molecule is freely diffusible and is, therefore, found in hemodialysates when the patients are placed on the artificial kidney for dialysis therapy. It is one of the many compounds which circulate in increased amounts in the body fluids of uremic patients, some of which may contribute to the signs and symptoms of uremia.

Procedure for isolation and identification of minute amounts of phenolic acids using paper chromatography and infrared spectroscopy

Abstract A simple procedure for obtaining good infrared spectra of compounds eluted from paper chromatograms has been described. As little as 25 μg of many phenolic acids may be isolated, characterized, and identified from paper chromatograms.

N-methyl-2-pyridone-5-carboxylic acid and N-methyl-2-pyridone-5-formamidoacetic acid isolated from dialysis fluids of uremic patients☆

Abstract N-methyi-2-pyricl.one-5-carboxylic acid(2-py acid) and N-methyl-2-pyridone-5-formamidoacetic acid (2-py hippurate) were isolated from hemodialysates from uremic patients. Identification was made by chromatographic techniques and infrared spectra. The significance of the presence of these compounds is still to be determined.