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Biomedical subjects

M Kazama

Publications and source records attributed to M Kazama.

At least 73 records · Page 4Linked to original sources

[Quality control of ISI/INR system in oral anticoagulant therapy].

Ten controlled plasmas and 4 thromboplastin reagents were distributed to 75 laboratories for measurement of prothrombin time (PT). The results were converted to prothrombin activity (PA). prothrombin ratio (PR) and international normalized ratio (INR). Among the 4 different ways of expression, the discrepancy between the results obtained by the different reagents was the smallest when the results were expressed by INR. However, the discrepancy of the results was still remained because of the different assay methods used routinely at these laboratories, even with the use of ISI/NR system (Instrumentation effects). In this study, reference curve of prothrombin time: INR was created using INR reference plasmas, which were selected from commercial control plasma using a standard thromboplastin reagent. INR's of 108 patients' plasmas were calculated by ISI/INR system on one hand, and by the use of the reference curve of the prothrombin: INR on the other hand. It was found that the discrepancy of the results obtained by different assay methods was significantly improved by the latter method, compared to those obtained by the conventional ISI/INR system.

Administration, Oral↗

[Essential thrombocythemia with Philadelphia chromosome].

Essential thrombocythemia is a myeloproliferative disorder not known to have consistent cytogenetic abnormalities. A 38-year-old woman with essential thrombocythemia having Philadelphia chromosome (Ph1) is reported. The patient first presented with gastrointestinal bleeding, accompanied by thrombocytosis. Treatment of the gastrointestinal bleeding did not influence the elevation of platelet counts. The patient's clinical and hematological manifestations were consistent with essential thrombocythemia, but not with any other myeloproliferative diseases. Ph1 chromosome was constantly proved in bone marrow preparations from this patient over two years and four months and gave us a certain impression that Ph1 chromosome might have had some relation to development of essential thrombocythemia to chronic myelogenous leukemia in this patient.

Adult↗

Quantitative analysis of fibrin-binding affinity of fibrinolytic components by frontal affinity chromatography.

Binding affinity of fibrinolytic factors to insolubilized lysine and fibrin was quantitatively measured by frontal affinity chromatography using lysine-Toyopearl and fibrin-Sepharose column. The highest binding affinity was found with recombinant tissue-type plasminogen activator (t-PA), followed by lysyl-plasminogen and glutamyl-plasminogen (Glu-PLg) with intermediate affinity, but very low affinity by single chain UK-type plasminogen activator, high molecular weight UK and low molecular weight UK. At the coexistence of EACA, fibrin-binding affinity of Glu-PLg was greatly reduced, but those of UK's were substantially unchanged. It was concluded that high fibrin-binding affinity of t-PA and plasminogens were largely related to the lysine-binding affinity of these enzymes, but that of UK's would be related to the other binding affinity.

Arginine↗

Analysis of human glutamyl- and lysylplasminogen by high-performance affinity chromatography.

An analytical system for the fibrinolytic system in the blood is described, based on high-performance affinity chromatography and a newly devised specific proenzyme detection procedure. Plasminogen subspecies in human plasma without any pretreatment (less than 100 microliters) were specifically separated on an high-performance affinity column. For detection they were continuously activated by urokinase, and their elution profile was determined by assay of the plasmin activity using a specific fluorogenic substrate. Preliminary data on plasma from a patient are presented.

Chromatography, Affinity↗

Procalpain is activated on the plasma membrane and the calpain acts on the membrane.

The mechanism of activation of human erythrocyte calpain was investigated using the immunoblotting technique with anticalpain monoclonal antibody. The purified calpain underwent a Ca2+-induced fragmentation of the 80 kDa subunit to 76 kDa and 36 kDa fragments. The behavior of the 76 kDa fragment in electrophoresis corresponded to the proteinase activity of calpain, whereas the behavior of the 80 kDa subunit and the 36 kDa fragment did not. When inside-out membrane vesicles were added to the reaction mixture of calpain and Ca2+ and the vesicles were separated from the supernatant solution by centrifugation, the 80 kDa subunit and 76 kDa fragment were found in the vesicle fraction. No other fragments were found in this fraction. On the other hand, the 80 kDa subunit and 36 kDa fragment were found in the supernatant fraction. When right-side-out membrane vesicles were added to the reaction mixture and the vesicles were separated from the supernatant fraction, no fragment was found in the vesicle fraction, while only the 36 kDa fragment was found in the supernatant fraction. These results indicate that the 80 kDa subunit of procalpain was bound in a Ca2+-dependent manner to the cytosolic surface of the plasma membrane and then underwent fragmentation to produce the 76 kDa fragment (active form) and that it expressed its proteinase activity at the surface of the membrane.

Antibodies, Monoclonal↗

Combination of high-performance affinity chromatography and specific detection of proenzyme applicable to the analysis of the fibrinolytic system of human plasma.

A procedure for the analysis of the fibrinolytic system in human blood was devised by combining high-performance affinity chromatography (HPAC) and specific detection of proenzyme. Components of the fibrinolytic system were separated by HPAC using Asahipak GS gel coupled with p-aminobenzamidine, and they were specifically detected by means of an on-line enzyme assay system. This system made it possible to quantitate not only Glu-plasminogen (Glu-Plg) but also Lys-plasminogen (Lys-Plg) in human plasma in a short time without pre-treatment. The effect of urokinase on the state of components of the fibrinolytic system in blood was studied. It was clearly shown that Lys-Plg is more susceptible to activation by urokinase than Glu-Plg (both in vitro and in vivo).

Chromatography, Affinity↗

A rapid and sensitive analytical procedure for human plasminogen subspecies. Combination of high-performance affinity chromatography and specific monitoring of proenzymes.

Human plasminogens specifically separated by high-performance affinity chromatography were specifically detected by a newly devised, on-line monitoring system, in which the proenzymes were activated by urokinase and plasmin activity thus generated was assayed. Presence of Lys-plasminogen as a constituent in the blood was demonstrated by both chromatographic patterns and biochemical experiments. This system made it possible to estimate rapidly not only Glu-plasminogen but also Lys-plasminogen in the plasma without any pretreatment. Its utility as a tool for clinical analysis of fibrinolytic system was suggested.

Chromatography, High Pressure Liquid↗

Mechanism and significance of kinin formation in nephrotic syndrome.

There were few reports demonstrating behavior of kinin and kininogen in the nephrotic syndrome. In this paper, coagulation factors related to contact activation, such as factor XII (FXII), factor XI (FXI), prekallikrein (PK), high molecular weight kininogen (HMWKG), and kinins were measured in 15 cases of nephrotic syndrome, and clinical significance of these results were discussed. Plasma FXII activity was markedly decreased in the onset and florid stages of nephrotic syndrome, and this decrease was not correlated with plasma albumin level, which suggested marked activation of this factor in these stages. However, the decrease of PK was slight at the above stages. Activations of contact factors were not parallely occurred with the marked consumption of FXII. Plasma kinin activity was not increased in the onset and critical stages of the nephrotic syndrome but increased in the convalescent and chronic stages, while HMWK level was maintained higher than normal throughout the course. Plasma angiotensin-converting enzyme (kininase II) activity was increased in the early stage and decreased lower than normal during the course of the disease. It was concluded that kinin formation in the nephrotic syndrome was not due to the activation of intrinsic coagulation system but due to release of kinin from low molecular weight kininogen. This increased level of kinin activity in convalescent and chronic stage may be related to the healing process during the course of this syndrome. Low kinin activity in the early stage of this disease might be also explained by increased kininase II activity.

Adolescent↗