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Biomedical subjects

K Miyazaki

Publications and source records attributed to K Miyazaki.

At least 793 records · Page 44Linked to original sources

Pyruvate kinase isozymes in various tissues of rat, and increase of spleen-type pyruvate kinase in liver by injecting chromatins from spleen and tumor.

Pyruvate kinase [EC 2.7.1.40] in various tissues of rats was separable into seven kinds of pI-isozymes by isoelectric separation with Ampholine carrier ampholytes; pI 5.4-isozyme, pI 5.6-isozyme, pI 6.2-isozyme (2 kinds), pI 6.6-isozyme, pI 7.4-isozyme, and pI 7.8-isozyme. Some of these pI-isozymes contained bound fructose 1,6-diphosphate (FDP). The bound FDP was completely dissociated when the pI-isozymes were salted out with ammonium sulfate. In the FDP-free form, pyruvate kinase was classified into three types, liver-type (type L) of pI 6.2, muscle-type (type M) of pI 7.4, and spleen-type (type M2) of pI 7.8. The liver-type isoenzyme had two kinds of FDP-binding sites; the pI 5.6-isozyme and pI 5.4-isozyme were obtained when one and two kinds of sites were bound with FDP, respectively. The association and dissociation of FDP at both sites were reversible in the presence and absence of 0.15 M KC1 (high ionic strength). The muscle-type isoenzyme had no FDP-binding site. The spleen-type isoenzyme had two kinds of FDP-binding sites, like the liver-type isoenzyme. When the ionic strength of solutions containing the enzyme and FDP was sufficiently low, one and two kinds of the sites could bind with FDP, converting the enzyme into pI 6.6-isozyme and pI 6.2-isozyme, respectively. FDP bound with one kind of site (the 2nd site) was easily dissociable, but FDP bound with the other kind of site (the 1st site) was not. Provided that the 1st site carried bound FDP, the 2nd site was associable at high ionic strength. The liver-type isoenzyme free of FDP and the spleen-type isoenzyme bound with FDP at both sites had similar pI values of 6.2 and were not separable by isoelectric separation. Some properties of these pI-isozymes were compared. When Rhodamine sarcoma was transplanted in rats, the content of spleen-type isoenzyme in the livers increased. When rats were injected with chromatin prepared from either Rhodamine sarcoma or spleen, the content of spleen-type isoenzyme in the livers again increased. This was not observed on the injection of chromatin prepared from liver, indicating that the factor capable of controlling the gene expression was present in chromatins of sarcoma and spleen but barely or not at all in chromatin of liver.

Animals↗

Studies on urinary kallikreins. I. Purification and characterization of human urinary kallikreins.

Human urinary kallikrein [EC 3.4.21.8] (HUK) was purified about 200-fold with an overall yield of 40 percent from crude powder by DEAE-cellulose chromatography, acetone fractionation, Sephadex G-100 gel filtration and DEAE-Sephadex A-50 chromatography. Its activity was 200 kallikrein units (KU) per A280. HUK from active fractions obtained by DEAE-Sephadex A-50 chromatography was separated into three active components showing isoelectric points of 3.9 (HUK-1), 4.0 (HUK-2), and 4.2 (HUK-3) by isoelectric focusing: each HUK component was homogeneous on disc electrophoresis. The approximate molecular weights of HUK-1, -2 and -3 were estimated to be 2.7 X 10(4), 2.7 X 10(4), and 2.9 X 10(4), respectively, by gel filtration on a Sephadex G-100 column. The optimum pH's of HUK-1, -2, and -3 in esterolytic action were found to be 8.0, 8.3, and 7.5, respectively, and they were fairly heat stable in comparison with other glandular kallikreins. The three components of HUK were weakly inhibited by Trasylol, but were not affected by soybean and ovomucoid trypsin inhibitors. They were strongly resistant to treatment with urea and weakly resistant to treatment with guanidine. The activation energies of HUK-1, -2, and -3 were found to by 1.17 X 10(4), 5.1 X 10(3), and 1.45 X 10(4) cal per mole, respectively. The Km values were estimated toward N-alpha-tosyl-L-arginine methyl ester (TAME), N-alpha-benozyl-L-arginine ethyl ester (BAEE), and N-alpha-benozyl-L-arginine methyl ester (BAME).

Aprotinin↗

Dog renal kallikrein: purification and some properties.

The contents of kallikrein [EC 3.4.21.8] in the kidneys of various animals were estimated and the activity was found to be most potent in dogs. The dog renal kallikrein (DRK) was located mainly in the kidney cortex. Following the activation of a dog kidney cortex homogenate with acetone, kallikrein was purified about 2,000-fold with an overall yield of 18% by diethylaminoethyl (DEAE)-cellulose adsorption, acetone fractionation, and chromatography on Sephadex G-75 and DEAE-Sephadex A-50. The final purified preparation of dog renal kallikrein had a vasodilator activity of 65.5 KU per A280, and appeared to be homogeneous both in disc electrophoresis and ultracentrifugal analysis. Its molecular weight was estimated to be approximately 3.8 X 10(4) from the sedimentation coefficient obtained by ultracentrifugation, and by Sephadex gel filtration. However, isoelectric fractionation of the purified DRK preparation gave three isoelectric point, 3.9, 4.1, and 4.3. The DRK had an optimum pH of about 8.6 and was stable at pH 8. This enzyme was hardly inhibited by Trasylol, soybean trypsin inhibitor, ovomucoid trypsin inhibitor or potato kallikrein inhibitors. These properties were compared with those of kallikrein from other sources; DRK appeared to be similar to urinary kallikrein.

Amino Acids↗

Immunologic cross-reaction between human and mouse tyrosinases.

Human tyrosinase, partially purified from metastatic malignant melanoma, reacted with antiserum prepared against tyrosinase purified from Harding-Passey mouse melanoma melanosomes, although the human and mouse tyrosinases were not completely identical immunologically. The human tyrosinae showed only one band on disc electrophoresis which corresponded in mobility to T2 tyrosinase of mouse.

Animals↗

Tyrosinase as glycoprotein.

Purified tyrosinase T1 was incubated with neuraminidase. The catalytic activity of tyrosinase was essentially retained, after this treatment. The tyrosinase band (Dopa stained) was transformed into a new less anodic form, similar to tyrosinase T2, on disc electrophoresis. The band of protein was also converted to the same position as the Dopa stained. The other hand, the only one PAS stained band of native tyrosinase T1 was splitted into the three slower-moving bands. One was consistent with Dopa and protein stained bands. The other two were much more slower than the former band and completely free of peptide and enzymic activity. The PAS-densitometric value of native tyrosinase T1 was almost equal to those of three separated bands in total. These results suggest that mammalian tyrosinase is a kind of glycoprotein.

Animals↗

The prophylactic use of thio-tepa and urokinase in transitional cell carcinoma of the bladder: a preliminary report.

The prevention of recurrences of bladder cancer was attemped in 48 patients by means of the combined intravesical instillation of thio-tepa and urokinase and in 28 patients through the instillation of thio-tepa alone. The recurrence rates of both therapies for the postoperative 18 months were 7.9 and 32.6 per cent, respectively, indicating a significant drop in the recurrence rate in the group subjected to the combined therapy. No significant difference was found between the 2 instillation groups in terms of the blood transmission of 32-P thio-tepa. Serious leukopenia was found in 2 of the 48 patients receiving the combined instillation therapy but we concluded that this was not attributable to the use of urokinase.

Adolescent↗

Reticulosarcomatosis originating from skin--A clinicopathological study.

The case is that of a 65 year-old male with reticulosarcomatosis originating from the skin. There were multiple tumors composed of reticulum cells located only in the skin, particularly around the large joints. The entire course of illness was three years and five months, during which period regression by irradiation, recurrence, or new formation of tumors were repeatedly seen. At the end systemic tumor spread not only of the skin but also in various visceral organs including lymph nodes occurred. From histological and electron microscopic examinations repeatedly performed with biopsy materials, and finally with autopsy materials it was ascertained that the tumor cells had become smaller in size with less lymphoid cell infiltration at the terminal stage.

Aged↗