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Biomedical subjects

M Takaoka

Publications and source records attributed to M Takaoka.

At least 163 records · Page 9Linked to original sources
PubMed1987

Lymphographic changes in young dogs after transplantation with adult worms of Dirofilaria immitis into the abdominal cavity.

Serial lymphographic studies were made in 4 dogs transplanted with adult worms of Dirofilaria immitis. Several changes of the lymphatic systems of the treated dogs such as dilatation, narrowing, tortuosity, backflow, collateral flow, leakage and lymphorrhea of lymphatics, as well as enlargement and filling defect of lymphnodes were observed at first 2 months after transplantation, comparing with the lymphograms before transplantation. Lymphographies were repeated further 4 and 7 months after transplantation. In our previous studies, the mechanism of chyluria due to human filariasis was not sufficiently explained beyond the speculation of the mechanical obstruction of lymphatic vessels by worm bodies. In the present studies, varied abnormal changes, especially back and collateral flow of the lymph vessels of popliteal and inguinal regions, could be produced in lymphatic systems in dogs by transplantation with adult worms of Dirofilaria immitis into peritoneal cavity. This fact suggests that a mechanism of filarial chyluria is due to systemic responses and changes of the lymphatics by substance of the body of filarial worms.

Animals↗
PubMed1986

Purification and characterization of rat urinary esterase A1.

An enzyme, esterase A1, which hydrolyzes tosyl-arginine methyl ester (Tos-Arg-OMe) was separated from esterase A2 and kallikrein of male rat urine and purified by a procedure involving ammonium sulfate fractionation, ion exchange chromatography, hydrophobic chromatography and gel filtration. The resulting preparation was apparently homogeneous, as assessed by polyacrylamide gel electrophoresis. The molecular weight of the preparation was estimated to be 27,000 by SDS-polyacrylamide gel electrophoresis and 30,000 by gel filtration. The enzyme was more specific for arginine methyl esters than for lysine methyl esters. The optimum pH determined with Tos-Arg-OMe as a substrate was 8.0 and the Km was 11.8 mM. The Tos-Arg-OMe esterolytic activity of esterase A1 was inhibited by soybean trypsin inhibitor, but not by aprotinin. In immunodiffusion analysis, the antiserum to esterase A1 formed immunoprecipitin arcs with this enzyme and the urine collected from rat bladder, but not with esterase A2, kallikrein, plasma and the urine collected from ureters. These results indicate that rat urinary esterase A1 differs from esterase A2 and kallikrein. The esterase A1 appears to be produced by accessory sex glands and excreted via the spermiduct into the urine.

Animals↗
PubMed1986

Purification of inactive kallikrein from rat urine.

An inactive kallikrein was purified from rat urine, and some of the properties of this enzyme were examined, in comparison with those of rat urinary kallikrein (RUK). The purified inactive kallikrein reacted with the antiserum against RUK and migrated slightly more slowly than RUK, on the immunoelectrophoresis. The molecular weights of the inactive kallikrein and RUK were estimated to be 44,000 and 38,000 by gel filtration, respectively. These results indicate that the rat urinary inactive kallikrein is immunologically identical with RUK, but this inactive enzyme has biochemical properties different from those of RUK, with respect to molecular weight and electrophoretical mobility.

Amino Acids↗
PubMed1986

Mechanism of hematuria. I. Electron microscopic demonstration of the passage of a red blood cell through a glomerular capillary wall in rat masugi nephritis.

Masugi nephritis was induced in Sprague-Dawley rats by an intravenous injection of rabbit anti-rat kidney serum. In the autologous phase of the disease, three of 18 rats manifested continuous hematuria. Ultrastructural examination of renal glomeruli by transmission and scanning microscopy revealed gaps in the basement membranes, and the transcapillary passage of red blood cells through the discontinuous regions in the hematuric rats. Control animals revealed no gaps in the glomerular basement membranes regardless of the method used in their preparation for electron microscopy. These data support the hypothesis that hematuria is a result of the passage of red blood cells through gaps in the glomerular basement membrane in Masugi nephritis.

Animals↗
PubMed1985

Activation of urinary inactive kallikrein by an extract from the rat kidney cortex.

Activation of purified urinary inactive kallikrein by an extract from the rat kidney cortex was investigated. The extract produced a dose-dependent activation of the inactive kallikrein and the optimum pH for this activation was 5.0. Marked depression of the activation was observed when the extract was pre-incubated with E-64, p-CMB and iodoacetate, but not with DFP, PMSF or pepstatin A. The molecular weight of the inactive kallikrein (Mr 44,000) was reduced to 38,000 by treatment with the extract, this molecular weight value being identical with that of urinary active kallikrein. These results indicate that the rat kidney cortex contains a protease catalyzing conversion of urinary inactive kallikrein into its active form, and that the protease has properties compatible with those of a thiol protease, but not of trypsin which has been used as a tool for the activation of urinary inactive kallikrein. The thiol protease is probably one of regulators of the kallikrein-kinin system in the kidney.

Animals↗
PubMed1985

Carcinoma arising in fibroadenoma: case report and review of the world literature.

To date 119 cases of "carcinoma arising in a fibroadenoma" have been reported in the world literature. A total of 120 cases, including the case described here, are analyzed. The mean age of the affected females was 43 years. A few patients complained of several disorders other than breast tumor before and during the development of the tumor. The tumor was most frequently located in the upper outer quadrant of the breast. Most carcinomas in fibroadenomas were lobular carcinoma in situ followed by duct carcinoma in situ. There was only one squamous cell carcinoma. The malignant process was confined to the fibroadenoma in over half of the cases. In some cases additional foci outside the fibroadenoma were reported. Radical mastectomy was the most frequent treatment. The prognosis was usually good.

Adenofibroma↗
PubMed1985

Renal inactive kallikrein as the possible origin of urinary inactive kallikrein in the rat.

An inactive kallikrein, which could be activated with trypsin was isolated from the rat kidney cortex using diethylaminoethyl (DEAE)-cellulose chromatography. The inactive kallikrein had no vasodilator action, whereas the injection of trypsin-activated form of this enzyme into the femoral artery of dogs resulted in a marked increase in the arterial blood flow. Apparent molecular weight of the inactive kallikrein was estimated to be 4.4 X 10(4) by gel filtration, and this enzyme was converted to the renal active kallikrein (M.W. 3.8 X 10(4] by trypsin. The inactive kallikrein is immunologically identical with the trypsin-activated form of inactive kallikrein and active kallikrein. There were no significant differences in the chromatographic behavior on a DEAE-cellulose column, Km value for prolyl-phenylalanylarginine-4-methylcoumaryl-7-amide hydrolysis and profile of inhibition by trypsin inhibitors between the active kallikrein and the trypsin-activated form of inactive kallikrein. The above properties of the renal inactive kallikrein were similar to those of inactive kallikrein found in the urine. These results suggest that the inactive kallikrein in the rat kidney would be proteolytically converted to its active enzyme and that a part of the inactive kallikrein would be excreted into urine in a form itself.

Animals↗
PubMed1985

Serum and urinary ferritin levels in patients with rheumatoid arthritis.

The serum and urinary ferritin levels in 52 RA patients were measured by the 2-site immunoradiometric assay method. Serum ferritin levels in RA patients correlated with C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) but not with serum iron levels and hemoglobin concentrations, although they were within the normal range. High serum ferritin levels were associated with sera with hyper gamma-globulin and rheumatoid factors. In sequential studies, serum ferritin changed in parallel with ESR, CRP and disease activity in a majority of the patients. The urinary ferritin levels and u/s ratios in some RA patients were higher than control values. Higher values were found particularly in the group of patients under gold therapy but not in groups under other treatments.

Adolescent↗
PubMed1985

Purification and characterization of rat urinary renin.

Rat urinary renin was purified by a procedure involving ammonium sulfate fractionation, pepstatin-aminohexyl-Sepharose 4B chromatography, ion exchange chromatography and gel filtration. The resulting preparation was essentially homogeneous, as assessed by polyacrylamide gel electrophoresis. The molecular weight of the preparation was estimated to be 39000 by SDS-gel electrophoresis and 40000 by gel filtration. The optimum pH determined with rat angiotensinogen was 7.0, and the Km was 3.6 microM. These properties agreed well with those of purified rat renal renin. The activity of urinary renin was specifically inhibited by anti-renin antibody. These results suggest that urinary renin may originate in the kidney.

Animals↗
PubMed1984

Purification to apparent homogeneity of inactive kallikrein from rat urine.

Inactive kallikrein was purified from rat urine by a procedure including ammonium sulfate fractionation, DEAE cellulose chromatography, phenyl-Sepharose CL-4B chromatography, and gel filtration on Sephadex G-100 and Sephadex G-75 columns. The resulting preparation was essentially homogeneous, as assessed by polyacrylamide gel electrophoresis. This preparation migrated as a single protein band on a SDS-polyacrylamide gel and the molecular weight was 41000. The purified material underwent marked activation by trypsin, but not by deoxycholate, Triton X-100, SDS or acidification. These results indicate that the purified inactive kallikrein is the precursor rather than a complex with a substance binding to the active form of kallikrein.

Animals↗
PubMed1984

Conversion of low molecular weight renin into the high molecular weight form by Cu2+ in the rat kidney.

The low molecular weight form of renin (M.W. 40000) in the extract of rat kidney cortex was converted into the high molecular weight form (M.W. 60000) in the presence of Cu2+ and this conversion was abolished following pretreatment of the extract with disodium ethylenediaminetetraacetic acid. Fe3+, Fe(CN)6(3-), Cd2+ and Zn2+ had no effects on the reaction of the molecular weight conversion of this enzyme. The reactivity in the formation of high molecular weight renin catalyzed by Cu2+ increased when the extract was previously dialyzed, indicating the presence of substance(s) that interfere with the binding reaction of renin. The high molecular weight renin produced by Cu2+ was stable against dithiothreitol, suggesting that the formation of disulphide bridge(s) is not involved in the reaction of renin with the renin binding substance. We also confirmed that for formation of the high molecular weight renin, Cu2+ must react with both the renin enzyme and the renin binding substance. Our findings provide new evidence related to the mechanism of molecular weight conversion of renin in the rat kidney.

Animals↗