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Biomedical subjects

A Hara

Publications and source records attributed to A Hara.

At least 505 records · Page 28Linked to original sources

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↗

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↗

Profiles of the female-specific serum protein in the Japanese river lamprey, Lampetra japonica (Martens), and the sand lamprey, Lampetra reissneri (Dybowski), in relation to sexual maturation.

The occurrence of female-specific serum protein (FSSP) was examined in the anadromous lamprey, Lampetra japonica, and a freshwater lamprey, Lampetra reissneri, by an immunodiffusion technique using antiserum raised against the serum of sexually mature female lamprey. A considerable amount of FSSP was consistently detected in the blood of vitellogenic, but not in that of nonvitellogenic, females of both species of lampreys. The relative amount of the FSSP tended to become larger in female lampreys at the spawning period. The FSSP may correspond to the yolk precursor protein which is incorporated into ovarian oocytes during the period of exogenous vitellogenesis in the lampreys.

Aging↗

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↗

Chemical properties and stereoisomerism of heterogeneous long chain bases in lysosphingolipids by positive ion fast atom bombardment mass spectrometry and carbon-13 NMR spectroscopy.

Positive ion fast atom bombardment (FAB) mass spectrometry of galactopsychosine and glucopsychosine was capable of showing not only the pseudo molecular ion peaks, but also various fragment ion peaks such as protonated sphingosine and its fragment ions. The percent distribution of sphingosine and dihydrosphingosine in each lysosphingolipid was determined by GLC of the trimethyl-silylated derivatives of long chain bases after methanolysis and was comparable to the relative intensities of ion peaks derived from the sphingosine and dihydrosphingosine groups. The FAB mass spectra showed that during the fast atom bombardment the sphingosine more preferentially gave rise to one and/or two fragment ions by loss of one and/or two molecules of water than the dihydrosphingosine did. The stereoisomerism of sphingosylphosphorylcholine containing mainly L-threo-sphingosine could be reconfirmed by carbon-13 NMR spectroscopy. Furthermore, although the carbon-13 NMR signals of sphingosine C-1, C-2, C-3, C-4, and C-5 showed significant chemical shift differences between D-erythro and L-threo-sphingosines of lysosphingolipids, it was concluded that the signal position of sphingosine C-3 was the most important for the determination of D-erythro and L-threo configuration in the long chain base moieties of lysosphingolipids.

Animals↗

Healthy HTLV-I carriers in Japan: the haematological and immunological characteristics.

The haematological and immunological characteristics of 34 healthy anti-HTLV-I antibody-positive individuals (HTLV-I carriers) in southwestern Japan were examined. No significant difference was noted between carriers and the controls in counts of RBC, WBC and the absolute number of lymphocytes. The serum IgG in the carriers was higher than that of the controls. The percentages of OKT4, OKT8, OKIa1 and B1-positive cells were found to be normal in the peripheral blood of the carriers, whereas the percentages of OKT11 and anti-Tac-positive cells were significantly higher in the carriers than in the controls. A correlation was observed between the percentages of anti-Tac-positive cells and the titres of anti-HTLV-I antibody in the carriers. After a 72 h incubation of peripheral blood lymphocytes with medium alone, the percentage of anti-Tac-positive cells tended to decrease in the controls, but to increase in carriers, with the appearance of large blastoid cells resembling blastic transformed lymphocytes cultured with mitogen. Tac and Ia antigens were markedly expressed on these large blastoid cells.

Acute Disease↗

Dynamic changes in plasma inactive renin levels in Bartter's syndrome after administration of captopril and angiotensin II.

Changes in plasma active and inactive renin concentration (ARC and IRC) after captopril administration and angiotensin II (AII) infusion were studied in six patients with Bartter's syndrome. A single oral dose of captopril (8-25 mg) lowered the blood pressure and increased both ARC and IRC. AII infusion elevated blood pressure, suppressed ARC and increased IRC. In this syndrome of high renin levels, infused AII appeared to increase inactive renin secretion by reducing its conversion to active renin. On the other hand, an acute fall in AII levels and/or renal perfusion pressure by captopril increased both active and inactive renin. This indicates that the increase in the secretion of inactive renin, stimulated by captopril, might exceed any increase in its conversion to active renin in patients with Bartter's syndrome, in whom the production of renin is accelerated, and conversion of inactive renin to active renin probably already operates near its maximum.

Adolescent↗

Prevention of nephrosclerosis and cardiac hypertrophy by captopril treatment of spontaneously hypertensive rats.

The relationship between hypertension and cardiovascular damage was assessed in three groups of spontaneously hypertensive rats (SHR): 1. stroke prone SHR (SHR-SP) treated orally with an angiotensin I converting enzyme inhibitor (captopril) (100-400 mg/L in the drinking water) from 6 to 35 weeks of age, 2. SHR-SP maintained on tap water until 30 weeks of age, 3. stroke resistant SHR (SHR-SR) maintained on tap water. The controls were Wister Kyoto rats (WKY) maintained on tap water. Captopril-treated SHR-SP showed blood pressure lower than that of untreated SHR-SP, similar to SHR-SR. The ratio of heart weight to body weight was 0.55% in SHR-SP, 0.39% in captopril-treated SHR-SP, 0.46% in SHR-SR, and 0.39% in WKY. The kidneys of SHR-SP showed glomerular sclerosis, glomerular fibrosis, tubular casts, interstitial cell infiltration and vascular wall thickening or hyperplasia of the small arteries and arterioles. The severe glomerular sclerosis was mostly distributed in the inner and middle portions of cortex. Immunohistological study showed IgG, C3 and fibrinogen in the glomeruli and arterioles in SHR-SP. In captopril-treated SHR-SP, similar to SHR-SR, only minor histological changes were seen and there was no deposition of IgG, C3 or fibrinogen. No changes were seen in WKY. Thus, it was concluded that nephrosclerosis and cardiac hypertrophy in SHR-SP are prevented by captopril. The role of the renin-angiotensin and kallikrein-kinin systems in organ pathogenesis in SHR-SP is discussed.

Animals↗

Cell surface antigen expression in cultured lymphocytes derived from healthy HTLV-I carriers.

We studied cell surface antigens on fresh and cultured peripheral blood lymphocytes (PBL) of healthy HTLV-I carriers. OKT4, OKT8 and OKIa1-positive cells were found to be within the normal range as compared with controls both in fresh and in cultured PBL. The percentage of Tac positive cells in HTLV-I carriers was shown to be higher in fresh PBL than that of controls. Furthermore the value increased significantly during cell culture in vitro and large blastoid cells appeared. The results suggested that HTLV-I proliferation in infected lymphocytes is activated in a serum-free environment and that small resting lymphocytes are transformed into Tac-positive large blastoid cells.

Aged↗

[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↗

Cerebral lipid and protein abnormalities in Menkes' steely-hair disease.

Menkes' steely-hair disease is characterized by abnormal copper metabolism accompanying progressive cerebral degeneration. Cerebral lipids and proteins of an infantile male patient with Menkes' disease were analyzed. The major lipid components in myelin, which included free cholesterol, phospholipids, galactosylceramide, sulfatide, and GM4 ganglioside were markedly decreased, indicating that the myelin was severely damaged by the defective copper metabolism. The degeneration of the myelin was also indicated by decrease in myelin basic protein and proteolipid protein, whereas gliosis in the white matter was biochemically confirmed by prominent increase in glial fibrillary acidic protein. Fatty acid analyses of phospholipids in the white matter revealed that the unsaturated fatty acids were severely decreased in phosphatidylethanolamine, phosphatidylcholine, and phosphatidylserine, and that the long chain fatty acids were also decreased in sphingomyelin. As both the desaturation of fatty acids in glycerophospholipids and the elongation of fatty acids in sphingomyelin are in general thought as markers for myelination, the results suggest that the progressive cerebral degeneration in the disease is due to dysmyelination rather than demyelination. The dysmyelination seemed to be supported by the fact that cholesterol ester which is thought as a marker for demyelination, showed no increase in the brain.

Brain↗

[Detection of urinary polyamine by a new enzymatic differential assay. (I). Fundamental study on a new enzymatic differential assay].

A new enzymatic method for determining urinary polyamine concentration by fractionation of the urinary acetyl conjugate into free polyamines with acylpolyamine amido-hydrolase and quantification using two kinds of amine-oxidase of different substrate specificity was examined. High recovery rates of urinary polyamine by enzymatic hydrolyzation were obtained, namely, 95 +/- 4% for diamine, 95 +/- 1% for spermidine and 99 +/- 2% for spermine. Furthermore, excellent linearity was demonstrated with up to 150 mumole/l diamine, up to 75 mumole/l spermidine and up to 50 mumole/l spermine. Although urinary polyamine concentration varied diurnally even after correction of urinary creatinine, day-to-day variation disappeared. In 24-hour pooled urine and voluntary urine, diamine, spermidine and spermine correlated relatively well. Urinary leukocytes and erythrocytes exerted no influence on urinary polyamine.

Diamines↗

[Detection of urinary polyamine by a new enzymatic differential assay. (II). Comparison with conventional method].

A new method of determining urinary polyamine concentration was compared with other techniques, namely, high pressure liquid chromatography (HPLC) and a polyamine test-enzyme kit. The values obtained by the new method, HPLC, and polyamine test-enzyme kit correlated well for all the fractions: diamine, spermidine and spermine. The correlation between the new method and the polyamine test-enzyme kit gave r = 0.9702, y = 1.1359x + 5.1266 (n = 48).

Chromatography, High Pressure Liquid↗

[Detection of polyamines by a new enzymatic differential assay. (4). Fundamental study on a new enzymatic differential assay of blood].

The enzymatic method for isolation and determination of urinary polyamines was modified to measure the polyamines in the blood. High recovery rates of polyamine in blood by enzymatic hydrolyzation were obtained, namely, 101.9 +/- 4.4% for diamine, 96.0 +/- 5.4% for spermidine and 104.1 +/- 3.3% for spermine. Furthermore excellent linearity was demonstrated. Within-run precision of polyamine in blood was excellent, namely, in C.V., 1.15% for Reaction 1, 2.11% for Reaction 2 and 2.79% for Reaction 3. This method was compared with high pressure liquid chromatography (HPLC), and a close correlation was demonstrated for all the fractions: diamine r = 0.8824, y = 1.367x+0.0417 (n = 15); spermidine r = 0.9878, y = 0.806x+5.218 (n = 15); spermine r = 0.9764, y = 1.068x-0.9195 (n = 15).

Chromatography, High Pressure Liquid↗

[Detection of polyamines by a new enzymatic differential assay. (5). Studies on polyamine in the blood of patients with malignant genitourinary diseases].

Using the new enzymatic assay for isolation and determination of polyamine in blood presented in Report 4, the polyamines in the blood were isolated and determined in 84 patients with genitourinary cancer. In the early diagnosis, the positive rates of each fraction were not so high, but, relatively high positive rates were demonstrated, when any one of the polyamines were found positive: namely, 85.7% in renal cell cancer, 66.7% in renal pelvic and ureteral cancer, 44.0% in bladder cancers. These results seem to support the usefulness of the new method, and encourage further investigation of polyamines in the blood as tumor markers.

Diamines↗