We have studied the relationship between the changes in tryptophan (free type and albumin bound type) in serum and its uptake in rat liver injured by i. p.administration of carbon tetrachloride. Total tryptophan concentration in serum remained high throughout the liver injury. Its high level was caused by elevation of free tryptophan resulting from a decrease in serum total protein, especially albumin, and a increase in free fatty acids.Hepatic uptake of tryptophan at high affininity sites (low Km) was impaired by liver injury, but that at low affinity ones (high Km) was not. A high level of tryptophan in serum should aid its hepatic uptake when the number of uptake sites on the liver cells surface is decreased because of liver injury.

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The twin assay of 17α-Hydroxyprogesterone (17-OHP) and human Thyroid Stimulating Hormone (hTSH) in dried blood spotted on filter paper was developed by using Enzyme Linked Immunosorbent Assay (ELISA) method. Horseradish peroxydase (HRP) was used as label enzyme, the enzyme activity of bound fraction after B/F separation was measured by adding hydrogen peroxide (H₂O₂) and ABTS. The assay range of 17-OHP and hTSH were 2.5-160 ng/ml and 0.5-80μU/ml, respectively. The coefficient of variation for 17-OHP and hTSH were 2.18-7.61% and 3.15-6.83%, respectively. The proposed method was applied to preliminary neonatal screening of congenital adrenal hyperplasia and hypothyroidism using one (3mmφ) dried blood disc.

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The bilirubin-diazo reactions have been investigated by using thirty six kinds of diazotized aromatic primary amines. Twenty nine of these diazo compounds yield red-violet coloured products with absorption maximum at about 500-550 nm, and the others green coloured products with absorption maximum at about 700nm. The latters are the products from the diazonium salts of o-, p-anisidine, o-, p-aminophenol, 2, 4-dinitroaniline, 2, 6-dichlo ro-4-nitroaniline, and p-aminoacetanilide.
It was assumed that the green coloured products are not the azobilirubin but the biliverdin based on the study of the spectrophotometric, kinetic properties of the reaction. The oxidation of bilirubin to biliverdin may be due to nitrous acid remained unreacted in the diazotization of aromatic primary amines.

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There is increasing agreement about the atherogenicity of intermediate density lipoprotein (IDL). We have previously demonstrated an increased cholesterol (Ch) concentration in the Sf20-60 lipoprotein fraction of diabetics. On the other hand, it is a matter of debate whether hyperinsulinemia too plays an important role in atherogenesis. Therefore, in order to determine the atherogenicity of IDL and insulin in diabetics, we conducted three lines of study.
First, Ch concentration in the IDL was examined in normolipidemic diabetics. Second, a lipoprotein profile, including subclasses of the triglyceride (Tg) rich lipoprotein fraction, was examined before and after the commencement of insulin treatment. Third, the particle size distribution of IDL and LDL was examined by electron microscopy. A comparison was made between control and insulin-treated diabetics.
Increased Ch concentrations were found in the IDL₁ (Sf20-60) fraction of normolipidemic diabetics, which suggests an important role of this fraction for the development of atheros-clerosis in normolipidemic diabetics. Insulin treatment raised the Ch/Tg ratio of the Tg-rich fraction (Sf 60-400). The appearance of this Ch-rich particle after insulin treatment may indicate the role of exogenous insulin for the development fo atherosclerosis. Insulin-treated diabetics had smaller and Ch-enriched VLDL remnants and larger LDL particles than did nondiabetic control subjects. Thus, we have demonstrated new evidence that insulin is deeply involved in the generation of atherogenic lipoproteins in diadetic subjects.

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Enzyme Linked Immunosorbent Assay (ELISA) for 17α-hydroxyprogesterone (17-OHP) in dried blood spotted on filter paper was developed. Glucoseoxidase (GOD) was used as labeling enzyme, and in the assay of enzyme activity, H₂O₂ generated from glucose substrate is measured by colorimetric reaction with tetramethylbenzidine (TMBZ)-peroxidase (HRP). The measurable range was from 6.25 to 200 pg/assay and the detection limit was 1.0pg. The coefficient of variation for 17-OHP concentrations of 6.25, 12.5, 25.0, 50.0,100.0 and 200.0pg/disc were 4.6, 6.9, 5.3, 6.1, 10.0, 12.9% respectively. The present study demonstrates the feasibility of a neonatal screening for congenital adrenal hyperplasia

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