The usefulness of the serum Cu/Zn ratio as a tumor marker for lung cancer was evaluated. Abnormally elevated levels of the ratio were detected in 58% of the patients with lung cancer. The mean value of serum Cu/Zn ratio was significantly higher in the patients with lung cancer than in the healthy controls, but the difference between the patients with lung cancer and patients with nonmalignant pulmonary diseases was not statistically significant. The serum Cu/Zn ratio was significantly higher in patients with an advanced stage of lung cancer than in patients with early stage of lung cancer. However, the receiver operating characteristic curve of serum Cu/Zn ratio for discriminating lung cancer from nonmalignant pulmonary diseases, was very similar to that of C-reactive protein. These observations indicate that although the serum Cu/Zn ratio is not a tumor specific marker for lung cancer, it may be a useful stage marker for patients with inflammatory and consumptive disorders such as lung cancer.

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We measured the concentrations of the total sulfated bile acids in urine (U-TSBA) by enzymatic colorimetry with an automated analyzer. The U-TSBA levels in healthy subjects decreased with age. Neither sex difference nor the effect of meal was found in the U-TSBA levels. The reference values are <19.48, <12.27 and <6.60μmol/g creatinine for the group of under 4 years old, 4-17 years old and more than 18 years old, respectively. The U-TSBA level increased significantly in patients with hepatobiliary diseases. The U-TSBA level showed a significant correlation with either serum transaminases activity, serum total bile acid level and serum direct bilirubin concentration in patients with hepatobiliary diseases. The measurement of U-TSBA was more efficient for detecting hepatobiliary diseases than that of urobilinogen and bilirubin in urine, bilirubin and alkaline phosphatase in serum and, almost the same as that of total bile acids, alanine transaminase and gamma-glutamyl transferase in serum. Since the determination of U-TSBA is not only a noninvasive procedure, but also a sensitive test for hepatobiliary diseases and urine collected at any time can be used for the test, it may be convenient as a routine liver test in the out-patient clinic.

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We studied the diazo reaction of the water-soluble photoproducts of bilirubin using nine kinds of diazonium salts to select the diazonium salt most suitable for the determination of serum bilirubin. The diazonium salt of 3-nitroaniline was found to be more suitable than that of sulfanilic acid used extensively in clinical practice. This diazonium salt reacted readily with not only bilirubin but also the photoproducts, and the reaction of patients' serum bilirubin was completed in 2 or 3 min. The change in the measurement values obtained using this diazonium salt before and after irradiation with a fluorescent lamp was smaller than that obtained by the enzymatic method or the diazo method using the diazotized sulfanilic acid.

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A new, totally enzymatic method for the determination of inulin in serum and urine, using inulase (EC 3.2.1.7.), fructokinase (EC 2.7.1.4), phosphoglucoisomerase (EC 5. 3. 1. 9), and glucose- 6- phosphate dehydrogenase (EC 1. 1. 1.49) is described.
The assay is carried out by means of a fructose determination after hydrolysis of inulin with inulase.
The calibration curve was linear up to 2g/l of inulin. The within- run coefficients of variation were found to be between 1.1 and 2.3%.
Data showing the consistent quantitative recovery of added inulin from serum and urine are presented.
Thirty-seven serum-urine samples for renal glomerular filtration rate were used to obtain correlations between this method (Y) and the thiosulfate method (X). The correlation coefficients and regression equations were as follows r=0.9785, Y=0.8902X-0.92.
This method is simpler and faster than those used in the past, and has shown itself to be practical for use in clinical laboratories.

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Stability of bilirubin was investigated under various temperature conditions (-20°C, 4°C, 25°C, 37°C) with or without lighting for 7 days.
The values of direct bilirubin and total bilirubin (direct bilirubin+indirect) decreased gradually as the temperature and/or time increased.
The ratio of the direct bilirubin to the total bilirubin changed little at-20°C or 4°C, but gradually lowered at 25°C over time (p< 0.05).
This was caused by the increase of unconjugated bilirubin (Bu) and the decrease of diconjugated bilirubin (dBc), monoconjugated bilirubin (mBc) and δ-bilirubin (Bδ).
When illuminated with light, bilirubin changed to photobilirubin or biliverdin etc., and the values of direct bilirubin and total bilirubin rapidly decreased. The ratio of direct bilirubin to total bilirubin increased with time. These results indicate that the photobilirubin is derived from Bu in indirect bilirubin, and it is hydrous bilirubin.

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An improved colorimetric method for the determination of phosphatidylcholine hydroperoxide is described. Phosphatidylcholine hydroperoxide was allowed to react with potassium iodide in the presence of acetylchloride at room temperature, and the liberated iodine was measured colorimetrically at 550 nm after the addition of starch in 10% aqueous acetic acid. A linear response was observed between 5 and 40 nmol.

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A highly sensitive and selective high-performance liquid chromatography (HPLC) method with ultraviolet detection was developed using column- switching system for the simultaneousdetermination of hypoxanthine (HX) and xanthine (XA) in human plasma and urine. The selective separation of this method is based on the combination of the column-switching technique and two different separation modes of chromatography (reversed- phase and cation- exchange chromatography).
By this method the successive simultaneous analysis of the two in any sample could be performed by the same HPLC conditions in a 35- min cycle. The lower limits of detection for HX and XA were both approximately 0.8 pmol per injection. The recoveries were 97- 103% and the coefficients of variation were less than 3%.

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We evaluated ‘Lana® 1, 5AG Auto’ which were reagents for the measurement of 1, 5-anhydro-D-glucitol (1, 5AG) using an automated analyzer. In this method, pyranose oxidase (PROD) is used for oxidation of 1, 5AG and hydrogen peroxide resulted from oxidation of 1, 5AG is detected by colorimetry. Glucose is oxidized by PROD and highly interferes in the measurement of 1, 5AG. Therefore, in the reaction system, glucose is treated with glucokinase and is phosphorylated to form glucose-6-phosphate which is unreactive to PROD. In this study, we tested the influence of sugars other than glucose on the reagents of 1, 5AG. The presence of xylose, sorbose, galactose and gluconolactone interfered positively with the measurement of 1, 5AG. But these sugars exist rarely in normal serum, they have little effect on the measurement of serum 1, 5- AG. In constituents of the blood, heavy hemolysis and bilirubin interfered negatively with the measurement of 1, 5AG. The lower limit of detection was about 0.5mg/l. Measurements by the automated analyzer were highly correlated with those by a conventional column- enzyme method, and the former method was superior to the latter in both sensitivity and reproducibility. The measurement takes 10 min/test and have an ability of 600 tests/h. These findings indicate that the method is simpler and more precise in the measurement of 1, 5AG than the conventional method.

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