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Biomedical subjects

H Sawada

Publications and source records attributed to H Sawada.

At least 343 records · Page 19Linked to original sources

Marked canal stenosis at the level of the atlas.

A 38-year-old man with severe canal stenosis at the level of the atlas is reported. The clinical manifestations were muscular weakness and wasting of the upper limbs and spastic paresis of the lower limbs, which all progressed slowly. The atlas was hypoplastic and its retrodental space was narrow. The spinal cord was markedly compressed between the odontoid process and the posterior arch of the atlas. The clinical manifestations improved after a posterior laminectomy of the atlas.

Adult↗

Inhibition of starfish oocyte maturation by leupeptin analogs, potent trypsin inhibitors.

Inhibition of subsite-substituted leupeptin analogs, potent trypsin inhibitors, on 1-methyladenine-induced germinal vesicle breakdown was investigated in a starfish, Asterina pectinifera. Of benzyloxycarbonyl(Z)-Leu-P2-argininals, the analog with Ser at P2 residue was the strongest inhibitor, and those with Pro, Leu greater than Thr greater than Gly were followed in this order. In Z-P3-Ser-argininals, ranking of the inhibitory ability was as follows: Phe greater than Leu much greater than Pro greater than Ala at P3 residue. Among 11 analogs synthesized, Z-Phe-Ser-argininal showed the strongest inhibition. The inhibitory potency of the analog was 100-fold stronger than that of leupeptin (acetyl-Leu-Leu-argininal). Thus, trypsin-like enzyme possessing a narrow subsite specificity participates in oocyte maturation in the starfish.

Adenine↗

Separation and properties of multiple forms of dihydrodiol dehydrogenase from hamster liver.

1. Five multiple forms of dihydrodiol dehydrogenase (EC 1.3.1.20) with similar molecular weights of around 35,000 were purified from hamster liver cytosol. 2. All the enzymes oxidized trans-dihydrodiols of benzene and naphthalene and reduced various carbonyl compounds, but showed clear differences in specificities for other alcohols and cofactors, and in inhibitor sensitivity. 3. Two NADP+-dependent enzymes were immunologically identified with aldehyde reductase (EC 1.1.1.2) and 3 alpha-hydroxytsteroid dehydrogenase (EC 1.1.1.50). 4. The other enzymes with dual cofactor specificity oxidized xenobiotic alicyclic alcohols, and one of them was active on 3 alpha- and 17 beta-hydroxysteroids with NAD+ as a preferable cofactor.

Alcohol Oxidoreductases↗

Cytogenetic studies on the adult T-cell leukemia in Japan.

Cytogenetic studies were performed on 16 patients with ATL seen in Northern Kyushu island; nine were patients with acute type leukemia, one with crisis type and five with lymphoma type. The serum antibody for HTLV-1 (ATLA) was positive in all patients and the phenotype of ATL cells were ERFC+, OKT3+, OKT4+, OKT6-, OKT8-, OKT10+, OKla1+/- and Tac+. Abnormal findings of chromosomes were observed in 15 patients. Thirteen patients were in near diploid range. One patient was in triploid range and one patient was in tetraploid range. The polyploid karyotypes were found only in lymphoma type patients. Trisomy 3 and trisomy 7 were observed each in three patients with acute type of ATL. The most frequent abnormal rearrangement was observed in the long arm of chromosome 6 and the break occurred at band 6q15 and 6q21 each in four patients in this series.

Acute Disease↗

Hemopoietic features of splenectomized mice bearing IL-3 producing T cell leukemia.

Hemopoietic responses were studied in splenectomized mice after transplantation of the hemopoietic colony stimulating activity producing leukemia, L8313. In non-splenectomized mice, the number of peripheral leukocytes was elevated to 4 x 10(5)/mm3 after transplantation. In contrast, it was below 1.7 x 10(4)/mm3 in splenectomized mice. Total cell, hemopoietic stem cell and progenitor cell numbers in the bone marrow decreased in both groups. Serum from splenectomized mice contained multi-colony stimulating activity although less effective than that from non-splenectomized mice. Extramedullary hemopoiesis was observed in splenectomized mice. These results suggest that invasion of leukemic cells to bone marrow results in a damage of hemopoietic microenvironment.

Animals↗

Monkey liver indanol dehydrogenase. Purification, properties, and kinetic mechanism.

Indanol dehydrogenase was purified to apparent homogeneity from monkey liver cytosol. The enzyme was a monomer with a molecular weight of 36,000 and pI of 8.7. The amino acid composition was determined. The enzyme oxidized alicyclic alcohols including transdihydrodiols of benzene and naphthalene in the presence of both NADP+ and NAD+, and reduced several xenobiotic carbonyl compounds in the presence of NADPH, the 4-pro-R hydrogen atom of which was transferred to the substrate. The results of fluorometric binding and kinetic studies are consistent with an ordered sequential mechanism with NADP+ binding first. The enzyme was inhibited competitively versus NADP+ and uncompetitively versus 1-indanol not only by chelating agents such as 1,10-phenanthroline and 2,2'-bipyridine but also by a nonchelating isomer, 4,4'-bipyridine, which suggests hydrophobic interaction of the aromatic compounds with the enzyme, which did not contain zinc. The enzyme was also inhibited by Cibacron blue dye, synthetic estrogens, and delta 4-3-ketosteroids. The inhibition by Cibacron blue was competitive versus NADP+ and noncompetitive versus 1-indanol, whereas those by hexestrol, medroxyprogesterone acetate, and progesterone were uncompetitive versus NADP+ and competitive versus 1-indanol, corraborating the ordered addition of the coenzyme prior to 1-indanol.

Alcohol Oxidoreductases↗

Identification of two dihydrodiol dehydrogenases associated with 3(17)alpha-hydroxysteroid dehydrogenase activity in mouse kidney.

Dihydrodiol dehydrogenase activity was detected in the cytosol of various mouse tissues, among which kidney exhibited high specific activity comparable to the value for liver. The enzyme activity in the kidney cytosol was resolved into one major and three minor peaks by Q-Sepharose chromatography: one minor form cross-reacted immunologically with hepatic 3 alpha-hydroxysteroid dehydrogenase and another with aldehyde reductase. The other minor form was partially purified and the major form was purified to homogeneity. These two forms, although different in their charges, were monomeric proteins with the same molecular weight of 39,000 and had similar catalytic properties. They oxidized cis-benzene dihydrodiol and alicyclic alcohols as well as trans-dihydrodiols of benzene and naphthalene in the presence of NADP+ or NAD+, and reduced several xenobiotic aldehydes and ketones with NAD(P)H as a cofactor. The enzymes also catalyzed the oxidation of 3 alpha-hydroxysteroids and epitestosterone, and the reduction of 3- and 17-ketosteroids, showing much lower Km values (10(-7)-10(-6) M) for the steroids than for the xenobiotic alcohols. The results of mixed substrate experiments, heat stability, and activity staining on polyacrylamide gel electrophoresis suggested that, in the two enzymes, both dihydrodiol dehydrogenase and 3(17)alpha-hydroxysteroid dehydrogenase activities reside on a single enzyme protein. Thus, dihydrodiol dehydrogenase existed in four forms in mouse kidney cytosol, and the two forms distinct from the hepatic enzymes may be identical to 3(17)alpha-hydroxysteroid dehydrogenases.

3-Hydroxysteroid Dehydrogenases↗

3(20)alpha-hydroxysteroid dehydrogenase activity of monkey liver indanol dehydrogenase.

Homogeneous indanol dehydrogenase from monkey liver catalyzed the reversible conversion of 3 alpha- or 20 alpha-hydroxy groups of several bile acids and 5 beta-pregnanes to the corresponding 3- or 20-ketosteroids. The kcat values for the steroids determined at pH 7.4 were low, but the kcat/Km values for the 3-ketosteroids were comparable to or exceeded those for 1-indanol and xenobiotic carbonyl substrates. The enzyme transferred the 4-pro-R-hydrogen atom of NADPH to the 3 beta- or 20 beta-face of the ketosteroid substrate. Competitive inhibition of the hydroxysteroid dehydrogenase activity of the enzyme by medroxyprogesterone acetate, hexestrol, and 1,10-phenanthroline suggests that both 1-indanol and hydroxysteroid are oxidized at the same active site on the enzyme. The specific inhibitor of the enzyme, 1,10-phenanthroline, suppressed the 3 alpha-hydroxysteroid dehydrogenase activity in the crude extract of monkey liver by 50%. The results strongly suggest that indanol dehydrogenase acts as a 3(20)alpha-hydroxysteroid dehydrogenase in the metabolism of certain steroid hormones and bile acids.

20-Hydroxysteroid Dehydrogenases↗

Dimeric dihydrodiol dehydrogenase in monkey kidney. Substrate specificity, stereospecificity of hydrogen transfer, and distribution.

Chemical cross-linking and NADPH binding studies suggested that the native dihydrodiol dehydrogenase from monkey kidney is a basic dimer having a molecular weight of 78,000 and one active site per the subunit. The enzyme oxidized specifically trans-dihydrodiols of benzene and naphthalene, whereas it catalyzed the reduction of dihydroxyacetone and dihydroxyacetone phosphate at a physiological pH, 7.4. The Km and kcat values for dihydroxyacetone phosphate were 5.0 mM and 4.3 s-1, respectively. The enzyme transferred the 4-pro-R hydrogen atom of NADPH to the carbonyl substrate. Immunochemical experiments using an antibody against the dimeric enzyme revealed the specific distribution of the enzyme in the kidney of this animal. By immunohistochemical staining with the specific antibody, the immunoreactivity was found in proximal and distal tubules of the cortex, and in the loop of Henle of the medulla.

Alcohol Oxidoreductases↗

Enhanced liver metastatic potential of alpha-fetoprotein-producing human gastric carcinoma after carbon tetrachloride-induced liver damage in nude mice.

The liver metastatic potential of alpha-fetoprotein (AFP)-producing human gastric carcinoma (NSC-3) was examined in male, BALB/c, nude mice. Metastatic nodules in the liver were produced by intrasplenic (IS) injection of tumor cell suspension prepared by trypsinization from subcutaneous NSC-3 tumor. The serum AFP level increased exponentially after IS injection along with the growth of metastatic nodules in the liver, and a positive correlation was observed between the estimated weight of metastatic nodules and serum AFP level. To investigate the effect of liver damage by carbon tetrachloride (CCl4) on the metastatic potential of NSC-3 cells injected intrasplenically, the mice were divided into 4 groups: Group 1 received IS injection of 1 x 10(6) of NSC-3 cells without CCl4 treatment; Groups 2, 3 and 4 received IS injection 7 days, 2 days and 1 day after CCl4 treatment, respectively. All mice were killed 64 days after IS injection. The incidence of liver metastasis was 80% in Group 1, but 100% in Groups 2, 3 and 4. The mean numbers of metastatic nodules per liver were 4.2 in Group 1, 16.8 in Group 2, 18.0 in Group 3 and 44.5 in Group 4. Significant differences in the mean numbers of metastatic nodules were observed between Group 4 and the other groups. It was clearly demonstrated that the metastatic potential of AFP-producing human gastric carcinoma cells (NSC-3) is enhanced in the situation prevailing after liver parenchymal cells are damaged by CCl4.

Animals↗

Inhibition of human placenta aldose reductase by tannic acid.

Tannic acid was found to be a highly potent inhibitor of human placenta aldose reductase. The most potent inhibitory component of the tannic acid was isolated and identified as penta-O-galloyl-beta-D-glucose, which showed an IC50 value of 70 nM. The inhibition by the gallotannin was reversible and of mixed type with respect to DL-glyceraldehyde as the varied substrate.

Aldehyde Reductase↗

Partial purification and characterization of epidermal plasminogen activator and their inhibitor.

Plasminogen activator (PA) and PA inhibitor were partially purified from 2-d-old rat epidermis and characterized in order to elucidate the enzyme-inhibitor interaction in epidermis. PA extracted with buffer containing KSCN was first purified by Blue-Sepharose affinity chromatography. Separation of two PAs, with relative molecular mass (Mr) of 66000 and 44000, was accomplished by Con A-Sepharose column chromatography. The Mr 66000 enzyme had the properties of tissue-type PA (t-PA), while the Mr 44000 enzyme showed those of urokinase-type PA (u-PA) as determined by immunological and fibrin-binding studies. PA inhibitor was extracted in 1,4-piperazinediethanesulphonic acid buffer and purified by (NH4)2SO4 precipitation, gel filtration followed by a Mono Q column in an FPLC system. This inhibitor showed Mr 60000 and inhibited human u-PA activity in a dose- and time-dependent manner, but did not inhibit the activity of t-PA from human and murine melanoma cells or plasmin. It inhibited epidermal PA, Mr 44000, more effectively than it did the Mr 66000 epidermal PA. It was stable at 60 degrees C for 60 min or between pH 5 and 11. This study indicates that both u-PA and t-PA function in normal rat epidermis. On the other hand, an inhibitor which preferentially acts against u-PA exists, but inhibitor to t-PA does not appear to operate under normal epidermal functions.

Animals↗

Purification and properties of multiple forms of dihydrodiol dehydrogenase from monkey liver.

Two major and two minor forms of dihydrodiol dehydrogenase with similar molecular weights of around 36000 were purified from monkey liver cytosol. All the forms oxidized trans-dihydrodiols of benzene and naphthalene and reduced aromatic aldehydes, but showed differences in charge, specificity for other substrates and inhibitor sensitivity. One major (pI 8.7) and one minor (pI 7.9) form of the enzyme exhibited high activity for alicyclic alcohols and sensitivity to o-phenanthroline. The other major form (pI 6.2) oxidized 3 alpha-hydroxysteroids and was inhibited by dexamethasone and indomethacin, whereas the other minor form (pI 5.8) showed high reductase activity for aldehydes including D-glucuronate and sensitivity to barbital and sorbinil, and cross-reacted with human aldehyde reductase. The results indicate that the multiple forms of monkey liver dihydrodiol dehydrogenase are indanol dehydrogenases, 3 alpha-hydroxysteroid dehydrogenase and aldehyde reductase.

Alcohol Oxidoreductases↗

[Clinical study of intrahepatic arterial infusion of unresectable hepatoblastoma and hepatocarcinoma in children].

Six cases of unresectable hepatic cancer in infant were treated with intra-arterial infusion therapy. The histological types were hepatoblastoma and hepatocellular carcinoma, 3 cases respectively. The clinical stages were 1 recurrent case in I, 1 in IIIA, 2 in IIIB and 2 in IV. Seldinger method and cannulation at laparotomy were employed in 4 cases and 2 cases, respectively. In the eldest case, a catheter with dual lumen reservoir developed in our department was inserted, making it possible to infuse drugs into hepatic artery and cutting off hepatic arterial blood flow temporarily. The anticancer drug used was ADM, CDDP, 5-FU, THP-ADM, and MMC; antiAFP-anticancer drug conjugate missile therapy was employed in 4 cases. According to image diagnosis, reduction or necrosis of tumor was observed in 5 cases. In all cases, AFP scores decreased. In 5 dead cases, 4 cases died of tumor enlargement (average survival time 16.3 months); 1 case died of DIC during chemotherapy. The other case could eventually undergo complete resection and is now alive. Intra-arterial infusion therapy seemed to be useful for patients of infant unresectable hepatic cancer.

Adolescent↗

[Rapid diagnosis of adenoviral conjunctivitis].

Adenoviral conjunctivitis is contagious and it should be diagnosed rapidly. Adenoviral ocular infection showed epidemic keratoconjunctivitis due to Ad8 and pharyngoconjunctival fever due to Ad3 but those clinical pictures are changing because of the appearance of new serotypes of adenovirus such as Ad4, 19 and 37 which are related with acute conjunctivitis. The diagnosis of viral infection is generally time consuming and complex. Enzyme-linked immunosorbent assay (ELISA) and immunofluorescent antibody (IFA) test, using monoclonal antibody to adenovirus hexon have been applied for rapid diagnosis. ELISA showed 75% sensitivity and 100% specificity in 59 cases with adenoviral conjunctivitis and was therefore shown to be more practical than IFA which showed only 67% sensitivity.

Adenoviridae Infections↗

Heterogeneous features of Ph-negative CML--possible existence of Ph-negative, bcr-rearrangement-negative CML.

We have examined eight patients with Ph-negative chronic myelocytic leukemia (CML). Two of the patients had the same molecular abnormalities as well as the same clinical and hematological features as those of Ph-positive CML. The other six patients showed no genomic rearrangement. This group was hematologically divided into four subgroups, namely chronic myelomonocytic leukemia, undifferentiated chronic myeloproliferative disorder, chronic neutrophilic leukemia and CML-like syndrome. This last subgroup resembled Ph-positive CML in many points except for rather moderate proliferation of granulocyte lineage, and it was difficult to clinically separate it from Ph-positive CML.

Adult↗