SUMMARY Glucose 6-phosphate isoenzyme patterns and chromosomes were studied in 25 primary liver tumors of the rat in order to determine whether the isoenzyme pattern and chromosomes change dependently upon neoplastic transformation, and whether certain changes in the isoenzyme patterns correlate with definite chromosomal changes. Tumors were induced in livers of male rats fed 3'-methyl-4-dimeth...

Two isoenzyme of beta-glucuronidase from a rat basophil leukaemia tumour were co-purified 4067-fold by (NH4)2SO4 precipitation and sequential chromatography on concanavalin A--Sepharose, Sephadex G-200, DEAE-cellulose, CM-cellulose and phosphocellulose. The purity of the mixture was established by the coincidence of the peaks of enzyme activity and protein at a molecular weight of 300 000 on Bi...

The primary structure of mitochondrial aspartate aminotransferase from chicken is reported. The enzyme is a dimer of identical subunits. Each subunit contains 401 amino acid residues; the calculated subunit molecular weight of the apoform is 44,866. The degree of sequence identity with the homologous cytosolic isoenzyme from chicken is 46%. A comparison of the primary structures of the mitochon...

We describe two new methods for the separation and quantification of the bone and liver isoenzymes of alkaline phosphatase (EC 3.1.3.1) in plasma. In the first, we use wheat-germ lectin to precipitate the bone isoenzyme. About 80% of this, but minimal liver isoenzyme, is precipitated. The activity of the bone isoenzyme is calculated from measuring the alkaline phosphatase activity in the precip...

The human leukemia cell lines HL-60, KG-1, KLM-2, ML-3, THP-1, and U-937 were treated with the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA). TPA partially or completely inhibited the proliferative activity of the cell cultures. The number of cells with the ability to reduce nitroblue tetrazolium increased in the TPA-treated cell lines HL-60, ML-3, THP-1, and U-937, whereas the cell ...

Lactate dehydrogenase isoenzymes can be distinguished kinetically by the fact that isoenzyme H is strongly inhibited a few seconds after the reaction is started if high concentrations of pyruvate are present, in contrast to the M isoenzyme. A new instrument that exploits this fact can measure both the total activity and the proportion of H isoenzyme in serum or plasma in 8 to 10 s. The instrume...

Applications and limitations of alkaline phosphatase as a tumor marker are discussed. This review focuses on three characteristic isoenzymes that have been found in the serum of cancer patients: (1) the Regan isoenzyme in bronchogenic carcinoma; (2) the Nagao isoenzyme in pleuritis carcinomatosa; and (3) the hepatoma alkaline phosphatase. Tumor variants of alkaline phosphatase are classified ba...

The two main alkaline phosphatase isoenzymes in serum from patients with extrahepatic biliary obstruction have been purified. Properties of these isoenzymes, such as electrophoretic mobility, separation on gel filtration, ultracentrifugation characteristics, Michaelis constants, and sensitivity to neuraminidase have been studied and compared with the isoenzymes of liver and bile. The results sh...

We determined the decay constant and distribution space of the MB isoenzyme of creatine kinase after intravenous injection of 440 to 720 U, in a group of seven adult baboons. The rate of decay of the isoenzyme was monoexponential, with a mean decay constant of 0.00175 min-1 (SD, 0.00019). The mean distribution volume obtained by extrapolation of the monoexponential curve to zero time was 5.22% ...