The purpose of the present study was to develop and evaluate electroimmunoassay (EIA) for human plasma apolipoprotein (Apo) B and quantify Apo B concentrations in plasma and lipoprotein density fractions from Japanese control healthy subjects, cord blood and pregnant women. LDL of narrow density range (LDL₂: 1.030<d<1.050g/ml) was isolated by ultracentrifugation. Antiserum against lipoprotein B was obtained by injecting LDL₂ intraperitoneally into rabbits. Double immunodiffusion and immunoelectrophoresis revealed this antiserum is monospecific to lipoprotein B. Electroimmunoassay of Apo B was performed essentially according to the method of Laurell. Concentration of antigen and antibody and time for electrophoresis were investigated. Linear relationship between height of rocket-shaped immunoprecipitates and antigen concentraton from 20 to 160μg/ml was observed utilizing sso-fold dilution of antiserum and electrophoresis for 5 hours with 10 volts/cm. The accuracy of the method was the highest with a peak height of 2 to sem. On the basis of 10 analyses of single sample, the standard error was found to be 2.0%. Apo B concentrations in plasma and lipoprotein density fractions from healthy control subjects, cord blood and pregnant women, were investigated. Apo B concentrations in plasma, VLDL, LDL and HDL from control subjects were 128±40, 11±4,103±7 and 13±sing/100 ml, respectively. Percent distribution of Apo B in VLDL, LDL and HDL were 9.0±3.2, 81.0 ±5.8 and 10.0±3.8%, respectively. Plasma Apo B concentration of the mothers (n=15) was 263±37mg/100ml, which was approximately two times of plasma Apo B concentration of control healthy subjects. However, there was no difference in Apo B distribution in lipoprotein density classes between pregnant women and control. In cord blood (n=15), plas ma Apo B concentration (48±16mg/100ml) was less than one half of control. Percent Apo B distribution in VLDL, LDL and HDL were 8.4, 87.7 and 4.0%, respectively. Percent Apo B concentration in LDL and HDL were higher and lower, respectively, than those in LDL and HDL from control healthy subjects.

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An enzymic method for the determination of inorganic phosphate in urine was established, based on the formation of hydrogen peroxide with purine nucleoside phospho rylase (PNP) and xanthine oxidase (XO).
Inosine+H₃PO₄ PNP→hypoxanthine+ribose-1-phosphate Hypoxanthine+2H₂O+2O₂XO→uric acid+2H₂O₂ H₂O₂+red. chromogen peroxidase→oxid. chromophore+ H₂O
The method was evaluated by the investigation of its precision, accuracy, sensitivity and specificity. It was concluded that this method was useful in clinical tests for the determi nation of inorganic phosphate in urine.

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In determining hydrogen perokide in any reagent system in which peroxidase is present, it is noted that presence of bilirubin jeopardizes the results in two ways, firstly in chemical reaction and secondary in physical manifestation.
The mechanisms of bilirubin interferences in above procedure are as follows:
(1): Bilirubin as a hydrogen donor of peroxidase interferes with the peroxidase reaction.
(2): Overlapping of the spectra, namely, for bilirubin and for chromophore in the peroxidase reaction is commonly obserbed in determining hydrogen peroxide.
To minimize the bilirubin interferences as in (1) and (2) in the peroxidase reaction syst ems with 4-aminoantipyrine (4AA)-phenol or 4AA-diethylaniline (DEA) as the chromophore, investigations were carried out.
In the peroxidase reaction system with AA4-phenol, the chemical interferences descri bed in (1) can be minimized by following procedures;(a) decreasing the pH value of pho sphate buffer,(b) decreasing the concentration of phosphate buffer,(c) decreasing the pero xidase activity,(d) decreasing the concentration of 4AA,(e) increasing the concentration of phenol.
In the peroxidase reaction system with 4AA-DEA, the chemical interferences described in (1) can be minimized by decreasing the pH value and/or the concentration of phosphate buffer.
The spectral interferences described in (2) can be averted by decreasing the pH value of phosphate buffer and using longer than 500nm wavelength in measurement.

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Quality control survey results are classified into several groups, and a tole rance ellips is plotted on X-Y chart for each group instead of the Youden plot. Systemic error and random error of each group are easily recognizable by inspection of the chart. Number of data in a group more than 30 is required in order to obtain the stable ellips and to elucidate appropriate survey evaluation.

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To decide an appropriate application of kinesitherapy to treat diabetics, effects of exercise on glucose and lipids metabolism were examined using 4 healthy subjects.
On the same subject, 13 test conditions were set in consideration of intensity and duration of exercise as well as relative starting time of the exercise after oral glucose administration, and the changes of BS, IRI, FFA and TG in the course of time were me asured. That is, using a treadmill, 3 kinds of exercises were given, namely, 60 minutes for 40%, 30 minutes fo r60% and 15 minutes for 80% of VO₂ max., respectively, and exercise starting time was set to be immediately, 30 minutes and 60 minutes after glucose admin istration.
When the exercises of 40% and 60% VO₂ max. were started immediately after glucose administration, the rises of BS and IRI were inhibited. Especially IRI concentration at the end of exercise showed a significant reduction (p<0.05) compared to that of oral glucose administration during the rest. When such an exercise was started 30 minutes and 60 minutes later, the reduction of BS and IRI was accelerated, and at the end of exercise nearly the same level as those of fasting levels. Such tendency was more remarkable in the exercise of 60% VO₂ max. than that of 40% VO2 max. On the other hand, in the exercise of 80% VO₂ max., it showed the higher BS and IRI concentrations compared to those of oral glucose administration during the rest time.

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A simple and rapid method for purification of LDH (L-lactate: NAD⁺ oxidoreductase; ECI.1.1.27) isozymes in human tissues was established by the affinity chromato -graphy employing N⁶(6-aminohexyl)-5'-AMP-Sepharose as bed material. The results were shown as follows:
1. Crude extract (hemolysate) or ammonium sulfate fractionates (heart, liver) were applied directly to the column. The adsorbed LDH was eluted with a solution of NADH. After removing NADH by dialysis, each LDH isozyme was isolated with a common ion 0-exchange chromatography.
2. Sodium dodecylsulfate polyacrylamide gel electrophoresis for LDH preparations from three different human tissues (erythrocyte, heart, liver) revealed homogeneous as protein in each case and also gave that the molecular weights of LDH A-and B-subunits were 34,500 and 35,000-daltons, respectively. Specific activities of the purified enzymes were 730IU/mg (liver, A₄), 700IU/mg (erythrocyte, B₄) and 678IU/mg (heart, B₄).
3. The rate of purification for the LDH in erythrocyte, heart and liver were 4120, 234, 429-folds and yields were 84 (B₄), 63 (B₄), 49 (A₄) percents, respectivery.
4. On the tion-exchange chromatography, some LDH fractions having electrophoretically abnormal behavior were isolated in each tissue preparation. The elimination of unknown protein (FX) having similar properties to LDH A₄ was also problematical in case of purification of LDH from liver.

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Apo lipoprotein A-I (apo A-I) obtained from delipidated serum high density lipoprotein (HDL) was isolated and characterized. HDL was obtained by three ultracentrifugations and was purified by gel-filtration. Apo A-I was isolated from apo HDL by two gel-filtrations in 1% SDS and 6M urea.
Apo A-I had a molecular weight of approximate 27,000 by SDS-polyacrylamide gel electrophoresis and had a characteristic amino acid composition showing low amounts of isoleucine and no cystine or cystein. The amino acid composition of apo A-I was compatible with the result report by Baker et al. Antisera against apo A-I were prepared and immunological propertsy of apo A-I were defined.

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Measurement of serum tobramycin and gentamicin by high-performance liquid chromatography (HPLC) was evaluated with the purpose to apply to the routine practice of medicine. The method is based on the technique reported by Anhalt but is slightly modified to achieve our purpose. Analytical procedure by HPLC includes:(1) extraction from serum using CM-Sephadex®,(2) separation of an extract by ion-paired chromatography,(3) derivation by post-labeled method. The time required to one assay is less than 30 minutes. The maximum within-day and between-day variance (CV %) were 2.9 and 6.2% respectively for measurement of gentamicin. The same degree of precision (4.0 %) and reproducibility (4.2%) were observed in tobramycin assay. The recovery ratio ranged from 95.4 to 105.6% in gentamicin and from 97.1 to 103.8% in tobramycin assay. The HPLC assay correlated well with bioassay, radioimmunoassay and enzymeimmunoassay for measuring serum concentration of tobramycin in sera from healthy subjects and patients.(n=142 or 154, r=0.92-0.98) The method may prove more suitable for aminoglycoside drug monitoring than other methods and conventional HPLC technique, as the technique employed in this study is rapid, cost-effective and appropriate to measure a single sample, if necessary.

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We studied assay method of urinary p-aminobenzoic acid (PABA) in PFD Test which is very significant for the assessment of exocrine pancreatic function.
At first, urinary conjugated PABA was hydrolyzed with 2.5 N hydrochloric acid. Then followed sodium nitrate soln. and colored soln. which contained 1-naphthol-2-sulfonate were added to a portion of the hydrolysate. 1-Naphthol-2-sulfonate reacted with PABA by diazo coupling reaction and yielded a chromogen with max. absorption at 505nm.
Linearity was maintained up to 100 mg/dl of PABA. Additional recovery of PABA was 96.5-101.6% and that of p-acetamidobenzoic acid was 98.8-99.9%.
The reproducibility of the method was satisfied (C.V. 0.665% at 58.6mg/dl).

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Interference of Cefoxitin (antibiotics) on urinary 17-OHCS assay is described. This drug and its metabolites show a reactivity with color reagent of 17-OHCS in which phenylhydrazine is dissolved.
In contrast with Cephalexin which shows reactivity with both color reagent and blank reagent of 17-OHCS, Cefoxitin shows reactivity only with color reagent so that results obtained show positive error, for example, 1 g of dose gives assay values of 10 to 15 mg/day as 17-OHCS excretion.
Furthermore, color produced by the reagent has a yellow same as Porter-Silber chromogen, so that the effect of this drug could not be recognized by an analyst.
From these results, it is preferable to quit an administration of this drug before the test

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The members of German Society for Clinical Chemistry (GSCC) committee contributed considerably to standardization of the enzyme activity assay and a reference method for creatine kinase (EC 2.7.3.2, CK) activity assay in which coupling enzyme reaction with hexokinase (EC 2.7.1.1) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) is used has been proposed in 1977.
This reference method for CK activity assay by GSCC seems to be a superior method because of the choice of activator for CK and avoidance of interfering reaction by adenylate kinase.
Reagent kit for CK activity assay (Boehringer-Mannheim Corp.) which composition is based on the reference method of GSCC is used for evaluation of the CK activity assay.
We obtained different result in point of a pre-incubation time, that is, according to the reference method of GSCC, pre-incubation time required is 5 min at 25° because significant difference was not recognized with pre-incubation of 5, 10, 20, 30, 60, 120, and 360min.
But our results showed that 30 min of pre-incubation is required to reach maximum activity for a serum sample, and about 60min for some control serum sample

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