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Biomedical subjects

H Okuda

Publications and source records attributed to H Okuda.

At least 343 records · Page 19Linked to original sources

[Diagnosis and treatment of colorectal cancer using monoclonal antibodies].

The clinical usefulness of monoclonal antibodies was discussed from the viewpoint of serodiagnosis, immunohistochemistry, radio immunodetection and therapy. Monoclonal antibodies against carcinoembryonic antigen (CEA) were shown to be more beneficial than polyclonal antibodies. Carbohydrate antigens such as CA 19-9 or CA 50 were also available as tumor markers of colorectal cancer to a certain extent.

Antibodies, Monoclonal↗

Neutral glyceride synthesis from glucose in human adipose tissue: comparison between growing and mature subjects.

Basal and insulin-stimulated neutral glyceride syntheses from glucose were studied in fat cells of different size (fat cell volume, 0.07-0.20, 0.20-0.60, 0.60-1.00, 1.00-1.50 micron3 X 10(6)) obtained from subcutaneous adipose tissues in 20 subjects aged 3 months to 67 years. In 0.07-0.20 or 0.20-0.60 micron3 X 10(6) fat cells, the basal rate of glucose conversion to neutral glyceride was significantly lower in mature (36 to 67 years old) than in growing (0 to 12 years old) subjects. In 0.60-1.00 or 1.00-1.50 micron3 X 10(6) fat cells, however, basal rate was not significantly different between the two groups. The stimulating effect of insulin on conversion of glucose to neutral glyceride was not significantly different from the basal rate in fat cells of each size taken from the mature subjects, whereas in fat cells from growing subjects, it was significantly different from the basal rate in each fat cell size category. These results indicate that when fat cell size is taken into account, not only is the rate of basal glucose conversion to neutral glyceride higher in growing subjects but also its responsiveness to exogenous insulin, and that insulin insensitivity of large fat cells, reported previously, may be influenced by age.

Adipose Tissue↗

A case of adiposis dolorosa: lipid metabolism and hormone secretion.

The present report describes a 53-year-old non-obese man with adiposis dolorosa whose pain was dramatically relieved by the intravenous injection of lidocaine. The patient showed a paradoxical response of growth hormone to thyrotropin-releasing hormone. In addition, in-vitro studies on adipose tissue metabolism revealed the reduced glucose conversion to neutral glycerides in painful adipose tissue. These abnormalities may be related in some ways to the pathogenesis of this disorder.

Adipose Tissue↗

Effects of stilbene derivatives on arachidonate metabolism in leukocytes.

The effects of various alpha-phenylcinnamic acid derivatives (i.e., alpha-(3,4-dihydroxyphenyl)cinnamic acid, alpha-(3,4-dihydroxyphenyl)-3-hydroxycinnamic acid, alpha-(3,4-dihydroxyphenyl)-4-hydroxycinnamic acid and alpha-(3,4-dihydroxyphenyl)-3, 4-dihydroxycinnamic acid) synthesized from 3,4-dihydroxyphenyl acetic acid and hydroxy-benzaldehyde, and 3,3',4-trihydroxystilbene obtained by decarboxylation of alpha-(3,4-dihydroxyphenyl)-3-hydroxycinnamic acid on rat peritoneal polymorphonuclear leukocyte lipoxygenase and cyclooxygenase activities were studied. 3,3',4-Trihydroxystilbene was found to inhibit the 5-lipoxygenase product, 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid (5-HETE), and cyclooxygenase products, 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and thromboxane B2; its concentrations for 50% inhibition (IC50) were 0.885 +/- 0.016 microM for the leukocyte lipoxygenase product, 5-HETE, 7.70 +/- 0.104 microM for the formations of HHT and 7.96 +/- 0.143 microM for the formation of thromboxane B2. Alpha-(3,4-Dihydroxyphenyl)cinnamic acid, alpha-(3,4-dihydroxyphenyl)-3-hydroxycinnamic acid and alpha-(3,4-dihydroxyphenyl)-3,4-dihydroxycinnamic acid also inhibited the formations of 5-HETE, HHT and thromboxane B2, although less strongly. Their IC50 values were, respectively, 91.3 +/- 3.62 microM, 947.5 +/- 28.7 microM, 453.3 +/- 229.3 microM and 148.8 +/- 50.6 microM for the formation of 5-HETE, 894.0 +/- 5.57 microM, 792.5 +/- 15.9 microM, greater than 1000 microM and 925.0 +/- 7.64 microM for the formation of HHT and 941.0 +/- 18.0 microM, 825 +/- 14.4 microM, greater than 1000 microM and 932.7 +/- 3.93 microM for the formation of thromboxane B2.

Animals↗

Studies on the adenylate kinase isozymes from the serum and erythrocyte of normal and Duchenne dystrophic patients. Isolation, physicochemical properties, and several comparisons with the Duchenne dystrophic aberrant enzyme.

Two species of adenylate kinase isozymes (ATP:AMP phosphotransferase, EC 2.7.4.3) from human Duchenne dystrophic serum were separated by Blue Sepharose CL-6B affinity column chromatography. One of these species was the "aberrant" adenylate kinase isozyme, found specifically in the Duchenne type of this disease (Hamada, M., Okuda, H., Oka, K., Watanabe, T., Ueda, K., Nojima, M., Kuby, S.A., Manship, M., Tyler, F., and Ziter, F. (1981) Biochim. Biophys. Acta 660, 227-237). The separated aberrant form possessed a molecular size of 98,000 (+/- 1,500), whereas the normal serum species of the enzyme was 87,000 (+/- 1,600) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, by gel filtration, and by sedimentation equilibrium. The sedimentation coefficient of each species was found to be 5.8 S for the aberrant form and 5.6 S for the normal form, respectively. The subunit size (Mr = 24,700) of the aberrant enzyme in 8 M urea proved to be very similar to that of the normal human liver enzyme (Hamada, M., Sumida, M., Okuda, H., Watanabe, T., Nojima, M., and Kuby, S.A. (1982) J. Biol. Chem. 257, 13120-13128), and the normal species subunit (Mr = 21,700) was found to be very similar to that of the normal human muscle enzyme (Kuby, S.A., Fleming, G., Frischat, A., Cress, M.C., and Hamada, M. (1983) J. Biol. Chem. 258, 1901-1907). Both species were tetrameric enzymes in the serum. The amino acid composition for the normal species was similar to that for the muscle-type enzyme, and that for the aberrant species was similar to the liver enzyme, but with some notable exceptions in both cases. Thus, the normal species had no tryptophan and two half-cystine residues/subunit; whereas, there was 1 tryptophan and 4 half-cystine residues/subunit of the aberrant molecule. The amino acid composition of both serum isozymes when compared to their respective muscle or liver-type enzyme differed mainly in the content of Glu, Asp, His, Leu, Ile, Gly. Kinetic properties of the two forms of human serum adenylate kinase were studied at limiting concentrations of both ADP3- and MgADP- in the reverse reaction and of AMP2- and MgATP2- in the forward reaction. The type of reaction mechanism compatible with the data was a two-substrate random quasiequilibrium type of mechanism without independent binding of the substrates and with a rate-limiting step largely at the interconversion of the ternary complexes.

Adenylyl Cyclases↗

The S-sulfate formation from 4-nitrobenzyl mercaptan in rat liver cytosol.

4-Nitrobenzyl mercaptan (NBM) was enzymatically transformed at pH 6.0 into its S-sulfate in rat liver cytosol fortified with 3'-phosphoadenosine 5'-phosphosulfate. At pH 7.4, the S-sulfate was not detected from the incubation mixture. 4-Nitrobenzyl alcohol was also transformed under the same incubation conditions into the corresponding O-sulfate at a higher rate at pH 6.0 than at pH 7.4. Under the incubation conditions used, NBM S-sulfate reacted with the substrate NBM at a significant rate to afford 4-nitrobenzyl disulfide. The disulfide formation from NBM and the S-sulfate occurred more readily at pH 7.4 than at pH 6.0, so that biologically formed NBM S-sulfate was strongly suggested not to remain unchanged in the incubation mixture at pH 7.4.

Animals↗

Inhibition of the formation of 5-hydroxy-6,8,11,14-eicosatetraenoic acid from arachidonic acid in polymorphonuclear leukocytes by various coumarins.

The effects of various coumarins (i.e. esculetin, daphnetin and fraxetin) on the formation of the 5-lipoxygenase product, 5-HETE, and the cyclooxygenase product, HHT, were studied. Esculetin (6,7-dihydroxycoumarin) was found to inhibit the formation of 5-HETE more strongly than HHT; its concentrations for 50% inhibition (IC50) were 1.46 +/- 1.02 microM for the formation 5-HETE and 57.3 +/- 17.3 microM for the formation of HHT. Daphnetin (7,8-dihydroxycoumarin) and fraxetin (6-methoxy-7,8-dihydroxycoumarin) also inhibited the formation of the 5-lipoxygenase product, 5-HETE, and the cyclooxygenase product, HHT; their IC50 values were, respectively, 6.90 +/- 2.07 microM and 2.57 +/- 0.088 microM for the formation of 5-HETE and 139.0 +/- 30.0 microM and 532.5 +/- 33.0 microM for the formation of HHT. The monohydroxy coumarin derivatives umbelliferone (7-hydroxycoumarin) and scopoletin (6-methoxy-7-hydroxycoumarin) and the coumarin glucosides fraxin (6-methoxy-7,8-dihydroxycoumarin 8-O-D-glucoside) and esculin (6,7-dihydroxycoumarin 6-O-D-glucoside) also inhibited the formation of 5-HETE, though less strongly. 4-Hydroxycoumarin and coumarin had no effect on either 5-lipoxygenase or cyclooxygenase at concentrations of up to 1 mM. Esculetin inhibited the formation of 5-HETE noncompetitively. In contrast, the dimethoxycoumarin fraxidin (6,8-dimethoxy-7-hydroxycoumarin) inhibited the formation of HHT more strongly than the formation of 5-HETE at a concentration of 1 mM.

Animals↗

Effects of stilbenes on arachidonate metabolism in leukocytes.

The effects of various stilbenes (i.e, 3,4',5-trihydroxystilbene, 3,4',5-trihydroxystilbene 3-O-D-glucoside and 2,3,4',5-tetrahydroxystilbene 2-O-D-glucoside) isolated from the roots of Polygonum species on rat peritoneal polymorphonuclear leukocyte lipoxygenase and cyclooxygenase activities were studied. Resveratrol (3,4',5-trihydroxystilbene) was found to inhibit the 5-lipoxygenase product, 5-HETE, and cyclooxygenase products, HHT and thromboxane B2; its concentrations for 50% inhibition (IC50) were 2.72 +/- 0.262 microM for the leukocyte lipoxygenase product, 5-HETE, 0.683 +/- 0.163 microM for the formations of HHT and 0.810 +/- 0.274 microM for the formation of thromboxane B2. Piceid (3,4',5-trihydroxystilbene 3-O-D-glucoside) and 2,3,4',5-tetrahydroxystilbene 2-O-D-glucoside also inhibited the formation of 5-HETE, HHT and thromboxane B2, although less strongly. Their IC50 values were, respectively, 55.3 +/- 15.3 microM and greater than 1000 microM for the formation of 5-HETE, 196.7 +/- 48.0 microM and 300.0 +/- 10.4 microM for the formation of HHT and 251.7 +/- 24.9 microM and 366.7 +/- 37.1 microM for the formation of thromboxane B2.

Animals↗

Regional differences in carboxylesterase activity between human subcutaneous and omental adipose tissue.

Human adipose tissue was shown to contain carboxylesterase activity when measured by methylbutyrate as substrate. The enzyme has the same characteristics as carboxylesterase purified from rat epididymal adipose tissue. Like lipoprotein lipase, carboxylesterase activity was higher in large than in small fat cells. Both cell size and carboxylesterase activity were greater in human subcutaneous than in omental adipose tissue. However, the linear regression lines between the enzyme activity and cell volume in the two tissues were almost superimposable, suggesting that cell size is a determinant of enzyme activity. Although the physiological significance of adipose tissue carboxylesterase must await further clarification, it is possible that the enzyme is related to the hydrolysis of long-chain monoacylglycerols.

Adipose Tissue↗

Comparison of ventricular function after Senning and Jatene procedures for complete transposition of the great arteries.

Postoperative right (RV) and left ventricular (LV) volume characteristics in patients with complete transposition of the great arteries were studied to compare ventricular function after Senning and Jatene procedures and to analyze RV dimensional change during systole in patients after the Senning procedures. RV end-diastolic volume (EDV) was 181 +/- 74% of normal (mean +/- standard deviation) and RV ejection fraction (EF) was 0.48 +/- 0.09 in 15 patients who underwent the Senning procedure. In 9 patients who underwent the Jatene procedure, LVEDV was 152 +/- 27% of normal and LVEF was 0.61 +/- 0.09. One patient with aortic regurgitation, 1 with aortic regurgitation and residual ventricular septal defect, and 1 with aortic regurgitation and generalized LV wall hypokinesia of unknown cause had large LVEDVs. Pulmonary ventricular EDV and EF were within normal ranges except in the patients with persistent pulmonary hypertension, who had large EDVs and low EFs regardless of the anatomic type of ventricle, either the left or right. The study of RV dimensional change in the Senning group showed a reduced systolic shortening of the anteroposterior diameter compared with the preoperative transposition of the great arteries and normal. This reduced shortening may be related to postoperative adhesion of the RV free wall to the anterior chest wall and fixation of the atrium secondary to the intraatrial repair. In conclusion, systemic ventricular function after intraatrial repair for complete transposition of the great arteries is depressed by unavoidable residua and sequelae: persistent RV hypertension, anatomy of the right ventricle and, possibly, postoperative adhesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Surgical Procedures↗

Decrease in alkaline triglyceride lipase in primary cultured hepatocytes from mice with sarcoma 180.

Primary cultured hepatocytes from normal mice and mice with Sarcoma 180 were characterized. The viability of freshly isolated hepatocytes from both sources was over 90% and the cells had a relatively stable population of DNA for a minimum of three days. After incubation with (3H)leucine, the syntheses and secretions of (3H)labeled trichloracetic acid-insoluble materials by hepatocytes from both normal and tumor-bearing mice increased similarly. However, the alkaline triglyceride lipase activity of a homogenate of freshly isolated hepatocytes from tumor-bearing mice was one-third that of cells from normal mice. The activity of hepatocytes from tumor-bearing mice increased less during culture than did the activity of cells isolated from normal mice.

Animals↗

Effect of alkaline cations on cyclic 3' 5'-AMP stimulated lipolysis in rat adipocytes.

In Krebs-Ringer phosphate medium, cyclic AMP had little effect on production of free fatty acids by fat cells in vitro, whereas dibutyryl cyclic AMP or epinephrine stimulated the production of free fatty acids. On the other hand, although under non-physiological condition, cyclic AMP was found to stimulate the lipolysis in simple KCl-Tris medium. The stimulation level was similar to that elicited by dibutyryl cyclic AMP. Cyclic AMP also stimulated lipolysis in LiCl-Tris or RbCl-Tris medium, but not in NaCl-Tris medium. In KCl-Tris medium, addition of divalent alkaline cations (Mg2+, Ca2+ and Sr2+, at 40 mM) completely inhibited the stimulation by cyclic AMP, but not those by dibutyryl cyclic AMP and epinephrine. No cyclic AMP-induced lipolysis was observed in homogenized or freeze-thawed cells.

Adipose Tissue↗

Recurrent carcinoma of the vagina following Okabayashi's radical hysterectomy for cervical carcinoma.

Between 1962 and 1976, 1847 cases of cervical cancer were treated by Okabayashi's radical hysterectomy. Of these, 42 cases developed vaginal invasive carcinoma and 5 developed vaginal intraepithelial carcinoma thereafter, giving a recurrence rate of 2.5%. The vaginal recurrence rate declined annually during the period 1962-1976, and was thought to be due to the efficacy of routinization of postoperative vaginal cuff irradiation. Of the 47 recurrent cases 33 were discovered within 2 years following the operation. Seventy-two percent of the recurrent cases were asymptomatic. The importance of close follow-up of the patients during the first 2 postoperative years was denoted. The incidence of developing a secondary vaginal cancer in the cases of cervical adenocarcinoma was 10.0%, higher than the 2.2% for squamous cell carcinoma. All the recurrent cases were treated with vaginal cuff irradiation, either alone or with external irradiation and/or chemotherapy. The 3-year survival rate of the patients who had vaginal recurrence alone was 40.0%, better than that of the cases accompanied with recurrence at the other sites.

Adenocarcinoma↗

Demonstration of hepatic triglyceride lipase-like activity in ascites fluid of mice with sarcoma 180.

The contents of apolipoproteins of plasma and ascites fluid of mice with Sarcoma 180 were measured. The apolipoprotein A-I contents of plasma decreased with development of the tumor. The apolipoprotein C-II and C-III contents of plasma reached a maximum on day 7 after tumor inoculation and then decreased. The apolipoprotein A-I content of the ascites fluid was lower than that of normal mouse plasma. In contrast, the apolipoprotein C-II and C-III contents of the ascites fluid were higher than those of normal mouse plasma. The ascites fluid of mice with Sarcoma 180 was found to contain at least two lipases. One had a pH optimum of 5.5-7.0 and was strongly inhibited by chlorpromazine. The other had an alkaline pH optimum and was inhibited only slightly by chlorpromazine. When the ascites fluid was applied to a heparin-Sepharose column 40-45% of the applied triglyceride lipase activity was retained on the column, which was eluted with 0.75 M NaCl. This fraction was inhibited by heat-inactivated (56 degrees C, 10 min) human serum, and was relatively resistant to l M NaCl. These results suggest that one of the lipolytic enzymes present in the ascites fluid of mice with Sarcoma 180 is hepatic triglyceride lipase.

Animals↗