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Biomedical subjects

H Sawada

Publications and source records attributed to H Sawada.

At least 415 records · Page 23Linked to original sources

[Detection of polyamines by an enzymatic assay. (6). Fundamental and clinical studies of a simple enzymatic method for determining total polyamines in blood].

A simple enzymatic method for determining total polyamines in human blood was established. Polyamines in trichloroacetic acid extract from 1 ml of blood were isolated on an anion-exchange column and measured spectrophotometrically by the end point assay using polyamine oxidase and putrescine oxidase. The recovery was as high as 98.4% and within-run precision (coefficient of variance: 1.82%), and the values obtained by this method were in fair agreement with those obtained by high performance liquid chromatography and the enzymatic differential assay methods previously reported. The polyamine levels were not changed when the blood was stored at -20 degrees C. Blood polyamine levels were measured in 108 patients with genitourinary cancers, 29 patients with benign prostatic hypertrophy, 18 patients with benign urological diseases and 25 normal subjects. Although polyamines were not significantly elevated in the low stage of cancer, elevation was observed at a high stage of malignancy. These results indicate that the determination of total polyamines may be useful to determine biochemically the malignancy of cancers.

Biomarkers, Tumor↗

Dihydrodiol dehydrogenases in guinea pig liver.

Four major and four minor dihydrodiol dehydrogenases, with similar apparent molecular weights of 28,000 to 34,000 but with different charges, were purified from male guinea pig liver cytosol. One of the minor enzymes catalyzed only the oxidation of benzene dihydrodiol with a high Km value of 5.0 mM and was identified immunologically with aldehyde reductase. The other enzymes oxidized xenobiotic alicyclic alcohols and 17 beta-hydroxysteroids as well as benzene dihydrodiol. These enzymes exhibited higher affinity for 17 beta-hydroxysteroids than for alicyclic alcohols and benzene dihydrodiol, and immunologically cross-reacted with testosterone 17 beta-dehydrogenase purified from the same source. Four major enzymes and one minor with Km values for benzene dihydrodiol of about 0.2 mM, possessed specificity for 5 beta-androstane--17 beta-hydroxysteroids and dual cofactor requirement, whereas the other two minor enzymes with high Km values of over 5 mM showed apparent NADP and 5 alpha-androstane specificity. The dihydrodiol dehydrogenase activity was localized in the cytosol of liver. The results indicate that the hepatic oxidation of dihydrodiols in the guinea pig is mediated by cytosolic testosterone 17 beta-dehydrogenase isozymes and aldehyde reductase. Testosterone 17 beta-dehydrogenase immunologically identical to the liver enzymes was detected only in kidney, whereas aldehyde reductase was detected in all tissues of the guinea pig.

Alcohol Dehydrogenase↗

Isolation of multiple forms of indanol dehydrogenase associated with 17 beta-hydroxysteroid dehydrogenase activity from male rabbit liver.

Seven multiforms of indanol dehydrogenase were isolated in a highly purified state from male rabbit liver cytosol. The enzymes were monomeric proteins with similar molecular weights of 30,000-37,000 but with distinct electrophoretic mobilities. All the enzymes oxidized alicyclic alcohols including benzene dihydrodiol and hydroxysteroids at different optimal pH, but showed clear differences in cofactor specificity, steroid specificity, and reversibility of the reaction. Two NADP+-dependent enzymes exhibited both 17 beta-hydroxysteroid dehydrogenase activity for 5 alpha-androstanes and 3 alpha-hydroxysteroid dehydrogenase activity for 5 beta-androstan-3 alpha-ol-17-one. Three of the other enzymes with dual cofactor specificity catalyzed predominantly 5 beta-androstane-3 alpha,17 beta-diol dehydrogenation. The reverse reaction rates of these five enzymes were low, whereas the other two enzymes, which had 3 alpha-hydroxysteroid dehydrogenase activity for 5 alpha-androstanes or 3(17)beta-hydroxysteroid dehydrogenase activity for 5 alpha-androstanes, highly reduced 3-ketosteroids and nonsteroidal aromatic carbonyl compounds with NADPH as a cofactor. All the enzymes exhibited Km values lower for the hydroxysteroids than for the alicyclic alcohols. The results of kinetic analyses with a mixture of 1-indanol and hydroxysteroids, pH and heat stability, and inhibitor sensitivity suggested strongly that, in the seven enzymes, both alicyclic alcohol dehydrogenase and hydroxysteroid dehydrogenase activities reside on a single enzyme protein. On the basis of these data, we suggest that indanol dehydrogenase exists in multiple forms in rabbit liver cytosol and may function in in vivo androgen metabolism.

17-Hydroxysteroid Dehydrogenases↗

Characterization of pulmonary carbonyl reductase of mouse and guinea pig.

Carbonyl reductases were purified from mouse and guinea pig lung. The mouse enzyme exhibited structural and catalytic similarity to the guinea pig enzyme: tetrameric structure consisting of an identical 23 kDa subunit; basicity (pI of 8.8); low substrate specificity for aliphatic and aromatic carbonyl compounds; dual cofactor specificity for NADPH and NADH; stereospecific transfer of the 4-pro S hydrogen of NADPH; and sensitivity to pyrazole, 2-mercaptoethanol and ferrous ion. Although 3-ketosteroids were extensively reduced by the mouse enzyme but not by the guinea pig enzyme in the forward reaction, the two enzymes similarly oxidized some alicyclic alcohols such as acenaphthenol, cyclohex-2-en-1-ol and benzenedihydrodiol in the presence of NADP+ and NAD+. A partial similarity between the two enzymes was observed immunologically, using antibodies against the purified guinea pig enzyme. The lung enzymes differ in several aspects from other oxidoreductases from extrapulmonary tissues. The immunoreactive protein was detected only in lung of the tissues of the two species.

Alcohol Oxidoreductases↗

Preclinical increase in activity of muscle microsomal trypsin-like protease in murine muscular dystrophy, C57BL/10-mdx.

Preclinical alterations of protease activities in skeletal muscles from 10-day-old dystrophic mouse, C57BL/10-mdx, were examined by using 10 fluorogenic peptide substrates. Among the activities tested, only Boc-Val-Pro-Arg-MCA-hydrolyzing enzyme of the muscle microsomes showed an about 6-fold higher level of activity in mdx mouse. The increase in activity was not observed in tissues other than skeletal muscle. The enzyme had a pH optimum between 8.5 and 11.0, and was inhibited with DFP and variety of trypsin inhibitors. The enzymatic activity transiently increased at 1-2 weeks of age, the preclinical or very early stage of the disease. These results imply that the increased level of a trypsin-like protease possibly present in muscle microsomes may be closely related to the manifestation of muscular dystrophy.

Aging↗

Carbonyl reductase of dog liver: purification, properties, and kinetic mechanism.

A carbonyl reductase has been extracted into 0.5 M KCl from dog liver and purified to apparent homogeneity by a three-step procedure consisting of chromatography on CM-Sephadex, Matrex green A, and Sephadex G-100 in high-ionic-strength buffers. The enzyme is a dimer composed of two identical subunits of molecular weight 27,000. The pH optimum is 5.5 and the isoelectric point of the enzyme is 9.3. The enzyme reduces aromatic ketones and aldehydes; the aromatic ketones with adjacent medium alkyl chains are the best substrates. Quinones, ketosteroids, prostaglandins, and aliphatic carbonyl compounds are poor or inactive substrates for the enzyme. As a cofactor the enzyme utilizes NADPH, the pro-S hydrogen atom of which is transferred to the substrate. Two moles of NADPH bind to one mole of the enzyme molecule, causing a blue shift and enhancement of the cofactor fluorescence. The reductase reaction is reversible and the equilibrium constant determined at pH 7.0 is 12.8. Steady-state kinetic measurements in both directions suggest that the reaction proceeds through a di-iso ordered bi-bi mechanism.

Alcohol Oxidoreductases↗

Physiopathological studies on granulocyte-macrophage colony stimulating factor and multi colony stimulating factor producing leukemia, L8313, induced by irradiation of C3H mice.

Radiation-induced L8313 leukemia bearing mice (L8313 mice) had marked granulocytosis with splenomegaly. Hemopoietic stem cells and progenitors increased in the spleen but not in the bone marrow. Spleen conditioned-medium and serum from L8313 mice induced the formation of granulocyte-macrophage colonies (CFU-GM), erythroid bursts (BFU-E) and mixed colonies (CFU-Mix). Bone marrow conditioned medium did not show such activity. A cell line (STIL-3) was established from the spleen cells of L8313 mice. Surface marker analysis showed that the established cells were suppressor T cell. The cells produced IL-3 and GM-CSF in vitro, and induce essentially the same "leukemic" response in recipient mice. Inoculation of STIL-3 in diffusion chamber also induced leukemoid reaction, i.e. a marked granulocytosis with splenomegaly. Therefore, L8313 leukemia may be linked to an abnormality of growth and production of hemopoietic factors in hemopoietic regulatory cells.

Animals↗

Purification and characterization of purple acid phosphatase from rat bone.

An acid phosphatase, which was immunochemically identical to splenic purple acid phosphatase, was purified to homogeneity from rat bone. The enzyme was a two iron-containing monomeric glycoprotein with a mol. wt of 36,000. The enzyme hydrolyzed aryl phosphates, nucleoside di- and triphosphates, thiamine pyrophosphate, phosphoenolpyruvic acid and acidic phosphoproteins. The enzyme was inhibited by ammonium molybdate, NaF and CuSO4 but not by tartrate and SH-reagents.

Acid Phosphatase↗

Bacterial adherence to gingival epithelial cells of rats with naturally occurring gingivitis.

Bacterial adherence to gingival cells was compared in rats with spontaneous gingivitis (SUS rat) and in control rats (RES rat). In the SUS rat, the number of adherent bacteria in gingival cells changed according to the progression of gingival inflammation. There was a correlation between the change of the number of adherent bacteria, progress of inflammation and pH in the pocket. In the RES rat, the number of adherent bacteria was constant and very small. In the adherence assay, adherence of Bacteroides intermedius to epithelial cells was dependent on the pH. Adherence of B. intermedius was better than that of other species. B. gingivalis and B. macacae showed good adherence but B. levii showed poor adherence. Adherence to the epithelial cells of the SUS rat was always better than that of the RES rat. These results were supported by scanning electron microscopic studies.

Adhesiveness↗

[Detection of urinary polyamine by a new enzymatic differential assay. (III). Studies on urinary polyamines in patients with malignant genitourinary diseases].

A new enzymatic method for isolation and determination of urinary polyamines was presented and basically studied in previous report 1 and 2 in comparison with existing techniques. Using the new method, urinary polyamines were isolated and determined in 56 patients with genitourinary cancer. Urinary polyamines were also determined in 63 controls consisting of 20 normal subjects, 25 patients with benign urological disease and 18 patients with BPH. The mean concentrations of Diamine, Spermidine, Spermine in 20 normal subjects were 16.6 +/- 5.8 mumoles/g Cr, 4.7 +/- 2.0 mumoles/g Cr and 0.99 +/- 0.51 mumoles/g Cr respectively. To emphasize the specificity to cancer, the level of positiveness was modified to a higher value than M+3SD. The positive values thus calculated were 40 mumoles/g Cr for Diamine, 15 mumoles/g Cr for Spermidine and 3 mumoles/g Cr for Spermine. The positive ratios of Diamine in patients with early cancer were 43% in renal cell cancer, 20% in pelvic and ureter cancer, 0% in bladder cancer and 20% in prostatic cancer. Those of Spermidine were 29% in renal cell cancer, 0% in pelvic and ureter cancer, 20% in bladder cancer and 40% in prostatic cancer. Those of Spermine were 29% in renal cell cancer, 20% in pelvic and ureter cancer, 20% in bladder cancer and 0% in prostatic cancer. In early diagnoses, Diamine indicated high positive ratios to renal cell cancer and Spermidine to prostatic cancer. Relatively high positive ratios were demonstrated, when any one of the isolated polyamines was found positive: namely, 57% in renal cell cancer, 20% in pelvic and ureter cancer, 30% in bladder cancer and 40% in prostatic cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Diamines↗