[Improving effect of the synthetic protease inhibitor E-3123 on experimental DIC in dogs].

Disseminated intravascular coagulation (DIC) is a severe syndrome associated with generalized, intractable bleeding and multiple organ failure. Synthesized protease inhibitors such as gabexate mesilate and nafamostat mesilate show an improving effect on DIC, which develops by a chain reaction involving the coagulation, fibrinolysis, complement and kallikrein systems. Experimental DIC was developed in Beagle dogs by infusion of 150 U/kg tissue thromboplastin (Group I), and the improving effect of a new synthetic protease inhibitor, E-3123, was examined. The following groups of animals were treated with drugs: Group II (n = 4) was given with 5 mg/kg/hr of E-3123; group III (n = 4) was given 10 mg/kg/hr of E-3123; and group IV was given 6 mg/kg/hr of gabexate mesilate (GM). Although improvement of the hemodynamics or peripheral circulation was not apparent, a slight, but insignificant, improvement of lactate/pyruvate was noted in the treated groups. On the other hand, the hemostatic abnormalities such as prolongation of prothrombin time and activated thromboplastin time; decreases of platelet count, fibrinogen and alpha 2-antiplasmin; and increases of fibrin degradation products were significantly improved in the treated groups. These results indicate that E-3123 is effective for improving experimental DIC, and it is suggested that E-3123 is applicable for the treatment of clinical DIC.

Changes in thrombomodulin level in plasma of endotoxin-infused rabbits.

Changes in the plasma thrombomodulin (TM) level were examined in endotoxin-infused rabbits. The plasma TM level in normal rabbits was 143.8 +/- 8.4 ng/ml (n = 67) and the molecular weight of the major TM was about 55 kd. Endotoxin (lipopolysaccharide, LPS, E. Coli B8:0127) was intravenously infused. LPS infusion increased the plasma TM level dose-dependently between 0.2 mg/kg and 5 mg/kg. When 5 mg/kg LPS was infused, the plasma TM level started to increase immediately and was 2.3 times higher than the control value within 1 hr. The molecular weight of the major TM was about 75 kd. This rapid increase in TM occurred before the decrease in fibrinogen content and the prolongation of prothrombin time. To examine the effect of circulating leukocytes on the TM increase in endotoxin-infused rabbits, 5 mg/kg LPS was infused into rabbits with leukocytopenia induced by X-ray irradiation. The maximum plasma level of TM was significantly lower than in the untreated rabbits given LPS. These data suggest that the increase in plasma TM is caused by LPS-stimulated leukocyte's prior to hemostaseological changes. It is well known that endothelial cells can be injured by stimulated leukocytes, so this increase in plasma TM probably reflects the deterioration of endothelial cells. This deterioration decreases the ability of endothelial cells to inhibit thrombosis, which would, in turn, contribute to the development of disseminated intravascular coagulation in endotoxin-infused rabbits.

[Analysis of hemostatic abnormality in various disease using molecular-I. Liver disease].

We examined the hemostatic abnormality of liver disease using hemostatic molecular markers, i.e. TAT, FPA and SFMC for coagulation, B beta 15-42, FDP, D dimer and PIC for fibrinolysis, t-PA and TM for vessel wall. The molecular markers for coagulation were generally increased in cases of liver disease, which was most sensitively reflected by FPA. On the other hand, it was postulated that SFMC was a marker reflecting the complication of DIC in these cases. Hyperfibrinolysis of liver disease was sensitively reflected by the increase of B beta 15-42, and an occasional increase of SFMC or FDP was thought to indicate the complication of DIC in these cases. A high correlation was found between t-PA and TM. It was postulated that the increase of the both markers in liver disease was due to deteriorated clearance by liver dysfunction, although TM is regarded as a marker reflecting endothelial injury. It was expected that visualization of hemostatic disorder of liver disease was made practical with the use of radar chart of these molecular markers.

Evaluation of international normalized ratios by a controlled field survey with 4 different thromboplastin reagents.

A nationwide survey has been performed in Japan involving 75 laboratories to assess the relative reliability of different methods of reporting prothrombin time results in anticoagulant control. The interchangeability of results using prothrombin time, prothrombin activity percentage, prothrombin ratio and international normalized ratios (INR) were compared with four different thromboplastin reagents and a range of coagulometers. A secondary batch of reference thromboplastin of human brain origin (BCT/454) was used to calibrate the local thromboplastins and for comparison of methods of reporting. The study revealed the closest agreement of the results between BCT and the other reagents, and the regression lines of these reagents were almost identical, when the results were reported as INR. Box-Whisker plot analysis showed that the distribution of the results was large with the more deficient plasmas with all methods of reporting. It was found by this analysis that the interchangeability of the results was greatest when the results were expressed by INR, because the mean values obtained of each plasma using different thromboplastin reagents gave the lowest CV and the frequency of the far-out data was least, compared with the other methods of expression. On the other hand, the type of coagulometer had almost as much effect as the thromboplastin reagent on the prothrombin time, even if INR was used. Interchangeability of INR would be further improved by providing ISI values for each reagent/instrument combination.

Reference values of hemostasis related factors of healthy Japanese adults. I: Circadian fluctuation.

The circadian fluctuation of hemostasis related parameters was examined on 16 healthy Japanese adults (male 9, female 7). Twenty one parameters were measured in this study, i.e. fibrinogen, the activity of F.II, F.V., F.VII, F.VIII, F.IX, F.X., F.XI, F.XII, antithrombin III, plasminogen, alpha 2-antiplasmin, as well as the antigen level of F.IX, von Willebrand Factor, protein C, tissue-type plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), beta-thromboglobulin, platelet factor 4, fibrinopeptide A, plasmin-alpha 2-antiplasmin complex and FDP. Fluctuation was not significant in almost all of the parameters except F.VIII, F.IX, beta-thromboglobulin, platelet factor 4, tPA and PAI-1. Although the fluctuations of F.VIII, F.IX, beta-thromboglobulin and platelet factor 4 were statistically significant, they remained within the normal ranges. On the other hand, tPA and free PAI-1 showed significant circadian fluctuation, of which levels were highest at 9:00. It was postulated that the significant circadian fluctuation of fibrinolytic activity will be regulated by the balance between tPA and PAI-1 in plasma.

Establishment of enzyme immunoassay of human thrombomodulin in plasma and urine using monoclonal antibodies.

Thrombomodulin, TM, is an endothelial cell membrane protein acting as a cofactor for the activation of plasma protein C. Soluble TM is present in plasma and urine of normal subjects. Enzyme immunoassay, EIA, for human TM was developed using mouse monoclonal antibodies against human placental TM in this paper. We obtained four types of the monoclonal antibodies against human placental TM. EIA sandwich method using three types of the monoclonal antibodies enabled us to measure almost all of 6 and 7 TM subspecies in plasma and urine, respectively, except 1 subspecies, 31 kDa TM. There was no interference from other components of plasma and urine in the assay conditions. Titration curves of purified TM in buffer or in normal plasma were linear within the range from 0.08 to 10 ng/ml. The coefficient of variation at 0.08 ng/ml TM was 4.7%. TM titer with buffer, assayed by this method, was reduced by the addition of thrombin at the final concentration of 20 U/ml, but the titer with plasma was not reduced even at 100 U/ml. These concentrations of thrombin are far larger than those which would be formed in circulation. TM levels in plasma and urine of normal subjects collected in the morning were 35.2 +/- 8.32 ng/ml (n = 346) and 111 +/- 31.6 ng/ml (n = 33), respectively. TM level in plasma did not differ from the level in serum. Circadian fluctuation of plasma TM was not significant in 10 normal adults, although a tendency of increase in TM excretion to urine was found rather in the day time than the other times.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

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.

Formation of soluble fibrinogen-fibrin complex in liquid human plasma; reflexion of coagulation process in storage.

Analysis was performed on a high-molecular fraction with fibrinogen antigenicity present in Liquid Human Plasma. This fraction, although seemed to resemble macromolecular FDP (fibrinogen degradation product) derived from stabilized fibrin, has many features not shared with the latter: 1) This fraction is sensitive to sodium dodecylsulfate (SDS) treatment. 2) Degradation products of this fraction obtained by digestion with plasmin, when eluted from a column of Sephadex G-200, exhibited a single peak of FDP-D antigenicity at the position of D-monomer. 3) In SDS polyacrylamide gel electrophoresis in the presence of dithiothreitol (DDT), no evidence for the presence of gamma-dimer was obtained. Thus, it is unlikely that the high-molecular fraction is formed through interchain cross-linking between fibrinogen molecules. The formation of the high-molecular complex was discussed in relation to coagulation process in stored plasma.