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Biomedical subjects

T Kosugi

Publications and source records attributed to T Kosugi.

At least 91 records · Page 5Linked to original sources
PubMed1986

Purification and some chemical properties of thrombin-like enzyme from Trimeresurus flavoviridis venom.

There has been no previous report indicating whether thrombin-like enzyme is contained in the venom of Trimeresurus flavoviridis which has the strongest toxic effect in the case of Habu bite. The present study was undertaken to clarify the existence of thrombin-like enzyme in Trimeresurus flavoviridis venom. As a starting material, lyophilized crude venom of Trimeresurus flavoviridis was used, and ammonium sulphate fractionation, gel filtration using Sephadex G-25, Sephadex G-150 and arginine-Sepharose affinity chromatography were carried out to separate and purify a thrombin-like enzyme from the crude venom. The enzyme was purified to a 137-fold increase in specific activity and the purified preparation revealed a single band on SDS-PAGE. The molecular weight of the enzyme was estimated to be 65,000-70,000 daltons by means of SDS-PAGE and gel filtration, and its isoelectric point was pH 4.5-5.5. Furthermore, the optimal pH of the enzyme was in the range of pH 8.0 to 8.5. Some of the differences in enzymatic properties between this enzyme and bovine thrombin were studied. The snake enzyme could coagulate only rabbit plasma and convert only purified rabbit fibrinogen to fibrin gel. In addition, this thrombin-like enzyme released only fibrinopeptide A from purified rabbit fibrinogen and did not release fibrinopeptide B.

Animals↗
PubMed1986

Inhibitors of coagulation-fibrinolysis system and platelet function in patients with vertigo.

Eight parameters of blood coagulation and fibrinolysis, i.e., the levels of fibrinogen, plasminogen, fibrinogen and/or fibrin-degradation products (FDP), alpha 2-macroglobulin, alpha 1-antitrypsin, CI-inactivator, antiplasmin activity and antithrombin activity, were measured in patients with vertigo. Furthermore, the ADP- and collagen-induced platelet aggregations were determined. The results were compared with those for healthy adults. The antiplasmin activity was significantly reduced (p is less than 0.001), the antithrombin activity was significantly reduced (p is less than 0.001) and the platelet aggregation significantly increased (p is less than 0.001), but the levels of fibrinogen, plasminogen, FDP, alpha 2-macroglobulin, alpha 1-antitrypsin and CI-inactivator were not significantly altered. The importance of the coagulation-fibrinolysis system and platelet function in patients with vertigo is discussed.

Antithrombins↗
PubMed1986

Total protein concentration in selectively collected secretions from the middle and inferior meatus of the nose.

To clarify the characteristics of nasal secretions, a method for collecting human nasal secretion was devised. Total protein concentration in selectively collected secretions from the nasal cavity was determined using biochemical techniques. Dry absorbent cotton was inserted in each middle and inferior meatus of the nasal cavity for 30 min, and put in a test tube with a plastic sieve for centrifugation. After centrifugation at 5,000 rpm for 20 min, 10 microliters were obtained to measure the protein concentration the nasal secretions was made using spectrophotometry. The amount of nasal secretion samples collected was 50 to 400 microliters per site. Nasal secretions collected from the right middle and inferior meatus contained 80 to 2,450 mg/dl and 260 to 3,270 mg/dl of protein, respectively, while those from the left middle and inferior meatus contained 80 to 2,200 mg/dl and 175 to 3,050 mg/dl, respectively. It was concluded that this new method was clinically useful for collecting nasal secretions, and it permitted selective collection from predetermined sites in the nasal cavity. The total protein concentration level of nasal secretions collected by this method was higher in the inferior meatus than in the middle meatus of the nose, with statistical significance.

Adult↗
PubMed1985

Elastase digested urokinase (ED-UK).

Elastase digested urokinase (ED-UK) was prepared from human high mol. wt urokinase (HMW-UK). It resembled low mol. wt urokinase (LMW-UK) in its mol. wt, specific activity, and active sites. The steady-state kinetic parameters of each enzyme for the activation of human Glu-plasminogen also resembled each other, as did their amidase parameters (with pyro-Glu-Gly-Arg-pNA).

Chromatography, Affinity↗
PubMed1984

Interaction of fibrinolytic activity between the tracheobronchial secretion and circulating blood of rats.

In order to clarify the origin and release mechanism of plasminogen activator in the tracheobronchial secretion of rats, electrophoretic analysis of the secretion and studies on the effects of certain vasoactive drugs on the activator activity in the secretion were carried out. From the results of electrophoretic analysis of the tracheobronchial secretion in non-treated rats, protease inhibitor composed of glycoprotein was not contained in the secretion in contrast to the circulating blood, but a protein of low molecular weight like albumin in the circulating blood was contained in the secretion. Furthermore, after injection of noradrenalin, the blood pressure was temporarily elevated and the fibrinolytic activity of the euglobulin fraction in the circulatory blood was also increased. Subsequent to this elevation of fibrinolytic activity in the circulating blood, the fibrinolytic activity in the tracheobronchial secretion increased. Based on these results, it is suggested that the increase of fibrinolytic activity in the circulating blood was due to increased release of plasminogen activator from the vascular wall, and the increased fibrinolytic activity of the tracheobronchial secretion was caused by a consequent increased transudation of plasminogen activator from the circulating blood into the tracheobronchial lumen.

Animals↗
PubMed1984

The role of fibrinolytic enzymes in inflammation and paranasal mucous membrane.

The distribution and role of tissue plasminogen activator (TA) and proactivator (PA) in various diseases of the nasal and paranasal cavity were investigated. The stronger the inflammatory and proliferative response of the paranasal mucous membrane, the weaker was the fibrinolytic activity of TA. The fibrinolytic activity of PA tended to be stronger than TA activity. It is considered that PA may play an important role in inflammatory enlargement and proliferation of the paranasal mucous membrane, but does not play an important role in carcinogenic enlargement and proliferation of the nasal and paranasal mucous membrane.

Enzyme Precursors↗
PubMed1984

[Thrombocyte function and problems of blood coagulation and fibrinolysis in head and neck cancer].

Platelet aggregation induced by ADP and collagen and five parameters of blood coagulation and fibrinolysis, (levels of fibrinogen, fibrinolytic activity of euglobulin, fibrinogen and/or fibrin degradation products, antiplasmin activity and antithrombin activity) were measured in patients with cancer of the head and neck. The results were compared with those from healthy controls. Enhancement of platelet aggregation, hyperfibrinolysis and hypercoagulable state were found in the circulatory blood of patients with cancer of the head and neck.

Blood Coagulation↗
PubMed1983

Localization of fibrinolytic activity in ovulation of the rat follicle as determined by the fibrin slide method.

The localization and changes of fibrinolytic activity during the process of ovulation were investigated by the fibrin slide method. In regular estrous cycle rats, fibrinolytic activity first appeared in the external area of the follicle wall (stigma) at 12 hr before ovulation. No activity was noted in the follicular cavity at this time. A peak of activity was seen at 2 hr before ovulation. After ovulation, the activity decreased markedly. The activity was completely inhibited on fibrin slides to which 10(-2) M trans-aminomethyl-cyclohexane carboxylic acid had been added. No activity was observed on plasminogen-free fibrin slides. These results suggest that fibrinolytic activity is one of the important factors involved in the rupture of the mature follicle wall, and that the fibrinolytic activity is due to plasminogen activator activity.

Animals↗
PubMed1983

Control of Arthus tonsillitis by the administration of an antiplasminic agent.

Previous reports have shown that fibrinolytic activity was increased in the circulatory blood of rabbits with Arthus tonsillitis. In this study, t-AMCHA was administered intravenously to rabbits, in order to clarify its role as an antiplasminic agent in the control of Arthus tonsillitis. First, to establish the proper method of administration of t-AMCHA and the quantity to be administered, a preliminary estimation was made of the requisite concentration of t-AMCHA in the circulating blood and tonsillar tissue. Then macroscopic observations and histopathological studies were performed on the tonsils of rabbits with Arthus tonsillitis after t-AMCHA administration at various doses. Finally, after injection of the antiplasminic agent, estimations were made of the plasma fibrinolytic activity in the blood of the rabbits under study. It was decided that administration of t-AMCHA at 3-hourly intervals could maintain a constant concentration of the substance in the tonsillar tissue. The marked hyperaemia and bleeding which were observed macroscopically and histopathologically at 1-2 days after the onset of tonsillitis, disappeared from the parenchyma of the tonsils and pharyngeal tissue surrounding the tonsils in the group receiving regular injections of t-AMCHA at 3-hourly intervals. After estimating certain parameters of the fibrinolytic system in the blood, it was found that fibrinolytic activity decreased and whole plasmin was not consumed as a result of the administration of t-AMCHA during the early stage of tonsillitis. The process of Arthus tonsillitis can thus be controlled by the administration of the antiplasminic agent.

Animals↗
PubMed1983

The role of plasminogen activator in ovulation.

The role of plasminogen activator in ovulation was investigated using the inhibitor, trans-aminomethylcyclohexane carboxylic acid (t-AMCHA). In the regular cycle rat, the plasminogen activator activity of the follicles increased from the diestrus to the estrus phase. In the latter phase, a proteolytic enzyme which was not inhibited by t-AMCHA appeared. After ovulation, the plasminogen activator activity decreased. When ovulation was induced in immature rats by pregnant mare serum gonadotrophin and human chorionic gonadotrophin, remarkable fibrinolytic activity appeared in the ovaries immediately before ovulation. When t-AMCHA was given in the ovulation-induced rats, the fibrinolytic activity of the ovaries was suppressed, the number of ovulated ova decreased and the timing of ovulation was delayed. When t-AMCHA solution was given to rats in the proestrus phase, ovulation was almost completely suppressed, but aprotinin solution exerted no effect on ovulation. These results suggest that plasminogen activator is a key enzyme in ovulation, and that the chain reaction from plasminogen activator to proteolytic enzyme (including collagenase) is of greater importance than that of plasminogen activator to plasmin.

Animals↗
PubMed1983

Studies on proactivator from the paranasal mucous membrane in chronic sinusitis.

We succeeded in differentiating the proactivator (PA) in tissue extract of paranasal mucous membrane with chronic sinusitis by the gel filtration technique. Furthermore, the results demonstrated that PA in the tissue extracts of the paranasal mucous membrane with chronic sinusitis and antrochoanal polyp was unrelated to the antigenicity of plasminogen. In particular, it was clarified that the tissue extract of antrochoanal polyp as a source of PA was not related to the antigenicity of plasminogen.

Antigen-Antibody Complex↗
PubMed1983

The detection of fibrinogen (or FgDP)-protamine sulphate complex in vitro and in the circulating blood.

In order to clarify the pathophysiological significance of the fibrinogen (FgDP)-protamine complex, the interaction between fibrinogen and protamine sulphate was studied in vitro and in vivo. Using the electrophoretic technique, an attempt was made to determine whether the complex could be detected in vitro and in the circulating blood. From the present studies, it has been clarified in in vitro experiments that the slower mobility of two peaks on immunoelectrophoresis represented a complex of protamine sulphate and fibrinogen (FgDP). Furthermore, the peak of slower mobility on crossed immunoelectrophoresis appeared in the circulating blood of a rabbit receiving administration of excess protamine sulphate. That is, in vivo experiments showed that a complex of protamine sulphate and fibrinogen (FgDP) could be detected in the circulating blood.

Animals↗
PubMed1982

Fibrinolysis-coagulation system in patients with cancer of the head and neck. Preliminary report.

Five parameters of blood coagulation and fibrinolysis, viz., levels of fibrinogen, fibrinolytic activity of euglobulin, fibrinogen and/or fibrin-degradation products (FDP), antiplasmin activity, and antithrombin activity, were measured in patients with cancer of the head and neck, and the results were compared with those of healthy adults. The fibrinogen content in cancer was significantly increased (p less than 0.001), the fibrinolytic activity of euglobulin significantly enhanced (p less than 0.001), the antiplasmin activity significantly reduced (p less than 0.05), the antithrombin activity significantly reduced (p less than 0.001), and the FDP level slightly increased, although the difference was not significant. The importance of the coagulation and fibrinolytic system in cancer of the head and neck is discussed.

Adult↗
PubMed1982

Differentiation of proactivator from tissue plasminogen activator with low molecular weight in the paranasal mucous membrane.

It has been shown that large amounts of fibrinolytic enzyme are contained in tissue extracts of the paranasal mucous membrane in patients with chronic sinusitis. However, the fibrinolytic enzyme in the tissue extracts has not yet been characterized by biochemical techniques. In the present study, proactivator was differentiated from tissue plasminogen activator with low molecular weight in extracts of the paranasal mucous membrane and the existence of the proactivator was thus demonstrated in tissue extracts. By analogy with the proactivator in antrochoanal polyps, this proactivator may play an important role in the proliferation and enlargement of the paranasal mucous membrane.

Enzyme Precursors↗
PubMed1982

Immunochemical studies of high and low molecular forms of urokinase.

The immunochemical properties of high and low molecular forms of urokinase (HMW-UK, MW 53,000, 124,000 IU/mg protein; LMW-UK, MW 32,000, 230,000 IU/mg protein) were studied with specific antisera against the functionally active heavy chain (H chain, MW 31,000, 201,000 IU/mg protein) and the light chain (L chain, MW 18,000) of HMW-UK. Using a double immunodiffusion technique, LMW-UK did not demonstrate L chain antigenicity in the molecule. Anti-L-chain serum exerted no effect on LMW-UK and the H chain, but anti-H-chain serum strongly inhibited the fibrinolytic activity of all the active enzymes (HMW-UK, LMW-UK, and H chain). Anti-L chain serum was found to exert an antifibrinolytic effect on HMW-UK.

Animals↗
PubMed1981

Differences in physicochemical properties between tissue plasminogen activators from human paranasal mucous membrane and pig heart.

In order to clarify the physicochemical property of tissue plasminogen activator (TA), tissue extracts of human paranasal mucous membrane and pig heart were studied by the biochemical techniques. The studies by gel filtration revealed that two plasminogen activators of different molecular weight were present in the extract of human paranasal mucous membrane. The existence of tissue plasminogen activator with a low molecular weight (LMW-TA) has not previously been reported. This molecular weight of this compound was lower than that of cytochrome c. On the other hand, the molecular weight of tissue plasminogen activator from pig heart (PH-TA) was similar to that of ovalbumin, about 46,000 daltons, as estimated by Sephadex G-150 gel filtration. From the physicochemical property of LMW-TA, it is suggested that the LMW-TA from paranasal mucous membrane with chronic sinusitis was produced by proteases, i.e. trypsin-like enzyme, present in the mucous membrane with chronic inflammation.

Animals↗