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We describe a simple, direct, and specific manual method for quantitative determination of total cholesterol in serum. In the method, which requires no extraction of the serum, a single stable reagent and 50 µl of sample is used. Serum cholesterol concentrations determined by this method did not differ statistically from those obtained by the reference method of Abell et al. Hemoglobin, bilirubin, and γ-globulin do not interfere unless present at markedly supranormal concentrations. Inter-run precision is about ±3% (95% confidence limits). more...

Three albumins were isolated from bread wheat seeds by gel filtration on Sephadex G-100 and differential preparative disc-electrophoresis on polyacrylamide gel. The proteins were obtained in sufficient yield and purity to carry out characterisation studies. The electrophoretic mobilities of the three albumins in polyacrylamide discs in glycine—Tris medium, pH 9·5, were 0·28, 0·34 and 0·39 (referred to that of bromophenol blue taken as 1). The isoelectric points were 6·40, 6·40 and 5·35 and the molecular weights 17, 700, 18, 200 and 18, 900, respectively. The amino acid compositions of the purified albumins were very similar. The correlation of the purified albumins with those isolated from bread wheats by other authors is discussed. more...

(1961). La Fonction Des Recepteurs Ampullaires. Acta Oto-Laryngologica: Vol. 53, No. sup163, pp. 79-88.

A rapid, convenient one-tube method for serum uric acid is described which employs a single addition of phosphotungstic acid. Serum proteins are precipitated and sufficient phospho-18-tungstic acid remains in the supernatant solution for oxidation of uric acid following alkalinization with sodium carbonate. Color development is accelerated by the use of a one-min heating period in a 100° heating block. The standard curve is linear to 20 mg/100 ml which permits the use of a single aqueous uric acid standard with each group of specimens. Only 0.2 ml of serum is required for a single analysis. The between-run precision is ± 5% (95% confidence limits) and the method yields results in excellent agreement with the phosphotungstate-uric acid method of Henry et al . more...

A simple method is described for directly determining serum urea nitrogen, wtihout deproteinization. The urea in 20 µl of serum or plasma is reacted with diacetylmonoxime in the presence of thiosemicarbazide and cadmium ion under acid conditions. The absorbance of the resulting rose-purple solution is measured at 540 nm. Results agreed excellently with those obtained by a reference method that makes use of urease and the Berthelot phenate—hypochlorite reaction for ammonia. An automated adaptation utilizing the AutoAnalyzer is also described, which eliminates the need for a dialyzer. A further advantage is that the same reagents are used for both methods. more...

The action mechanism of the alkaline halides in the carrier distillation process has been studied. The temperature data in the anodic charge allow to consider the alkaline carriers as melted; a solvent action of the carrier salt in respect to the oxide impurities contained in the U 3 O 8 matrix is supposed. The possibility of some thermochemical reactions in the anodic cup has been evaluated; the reaction products, formed during arcing, have been identified by X-ray diffraction analysis. The X-ray diffraction data and the thermodynamic calculations generally are in rather good agreement. more...

Cysteine oxidase activity has been determined in developing rat retina. Enzymic activity is present in 55, 000 × g supernate and in the crude mitochondria. Activity is rather low at birth; but increases with age; in mitochondria it reaches its maximum value at the 25th day while in supernate it increases more rapidly, reaching its maximum value 20 days after birth; unlike in the mitochondria, the activity of supernate considerably decreases during further development. The reason and significance of the postnatal changes in the mitochondrial cysteine oxidase activity are briefly discussed in relation with taurine formation. more...

1. Taurine levels have been determined in eight rat organs. 2. During postnatal growth the taurine content in retina, heart, small intestine, spleen and lung increases with advancing age, although adult values are not reached at the same time. 3. In contrast the taurine content decreases with age in brain cortex, liver and kidney. 4. The taurine in subcellular fractions of adult, 20-day-old and 5-day-old rat tissues exists predominantly in the cytosol of the cell. Taurine content in particulate fractions shows marked variations during development in the different organs. 5. Taurine distribution in the subcellular fractions suggests that some of the cellular taurine in the tissues is not freely mobile in cytosol. more...

A method is described for measuring serum lactic dehydrogenase isoenzymes by use of a commercial electrophoresis system. Six samples are simultaneously electrophoresed on cellulose acetate plates to separate the five isoenzymes, which are made visible by overlaying and incubating the electrophoresed plate with another plate saturated with lactate, phenazine methosulfate, and INT (a tetrazolium dye). The pattern is qualitatively assessed, or the plates are made transparent with dimethylsulfoxide— propanol and the isoenzymes measured densitometrically. The normal range for each isoenzyme, determined on 39 nonmedicated, nonfasting men and women, agrees with reported values. Duplicate plates are obtained for each serum analyzed. The entire procedure requires 2 h. more...