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Practical application of turbidimetrical method for the diagnosis of haemostasis disorders in babies with acute intestinal infections (AII) is described. The results of plasma biochemical analysis show that disturbances in balance between coagulation and fibrinolytic systems takes place in patients with this pathology. The correlation between biochemical parameters and clinical characteristics is observed. As follows from our data, the phase of the haemostasis disorders in babies with AII does not depend on etiology of the disease, but indicates its severity.

In 20 patients with acute myocardial infarction the parameters of coagulation and fibrinolysis were evaluated. A high degree of the correlation between the routine and turbidimetric methods was found. Turbidimetric express-micromethod may be widely used for monitoring coagulation and fibrinolysis parameters in patients with acute myocardial infarction.

3-week heparin treatment (25000 U/day) of 38 patients with diabetic glomerulosclerosis (DGS) produced positive results in 31 of them, was ineffective in 5 patients and induced complications in 2 cases. Prognostic criteria of heparin treatment efficacy basing on hemostatic changes on day 7 have been developed. Hemostasis was controlled most effectively in patients receiving heparin by a new graphic turbidimetric method capable of objective registration of clotting and fibrinolysis in one plasma portion. Because individual sensitivity to heparin widely varies and this variability manifests as early as first days of treatment, control over hemostasis system in heparin day dose 25000 U/day is advisable before treatment, on treatment day 3, 7 and on aftertreatment day 2.

Effects were studied of hemosorption on the system of homeostasis in patients with chronic glomerulonephritis presenting with nephrotic syndrome. An optimum graphic express method of control of the homeostasis system state was found, permitting predicting thrombohemorrhagic complications after single-session hemosorption (significance 99.9%). Strategies were identified for correction of changes in coagulogrammes in such patients along with devising measures to prevent the above complications.

Dependence of fibrinolysis parameters on the concentration of inhibitors of fibrinolytic process has been studied when using turbidimetric method. It is shown that the process of destruction of fibrin clot formed in diluted blood plasma is subjected to the Michaelis-Menten ratio. The constant of inhibition of fibrinolytic process in diluted plasma activated by prothrombin and streptokinase is 10 and 0.5 microM for 6-aminohexanoic acid and contrykal, respectively.

Disorders of haemostasis and fibrinolysis were studied in 54 patients of various age with arterial hypertension by turbidimetric express micromethod. Activation of coagulative system and inhibition of fibrinolytic activity tending to get more pronounced with age were found in patients with hypertonic disease at II stage and systolic arterial hypertension. Turbidimetry has considerable advantages: it can be performed rapidly, requires as much as 0.1 ml of plasma for the assay and provides complete information about the state of haemostasis and fibrinolysis. The method may be important in detecting minor signs of disseminated intravascular coagulation in patients with hypertonic disease.

Heparin therapy (25,000 U/day) of 38 patients with diabetic glomerulosclerosis resulted in improvement in 31 (82 +/- 6%). The treatment was not effective in 5% and complications were seen in 2 patients. Blood coagulation control is necessary during heparin treatment and turbidimetry proved to be highly informative in objective registration of coagulation and fibrinolysis processes.

A method has been developed to determine six parameters of coagulation and fibrinolysis by means of turbidimetry; 0.1 ml of dissolved plasma after its activation with thrombin and streptokinase is used. Testing conditions which permit performing express diagnostics of haemostasis disturbances and controlling their correction have been optimized.

A new turbodimetric proximate-micromethod has been used to determine six indices of blood coagulation and fibrinolysis (coagulation time, coagulation rate, maximal absorption, fibrinolysis rate, time of fibrin semilysis and complete lysis) in young donors, newborns, healthy pregnant women, healthy elderly and old age people. A positive correlation of the results obtained using the method suggested by the authors and conventional methods is found for the indices of blood coagulation and fibrinolysis. It is revealed that the above indices change depending on the physiological state of the human organism.

Affinity chromatography of plasminogen and its proteolytic fragments on immobilized fibrinogen TSD fragment has shown that the latter contains a plasminogen-binding site which is complementary to the lysine-binding site(s) of plasminogen molecule 1-3 kringle structures.

It was demonstrated that plasminogen and the plasmin heavy chain form a complex with an immobilized fibrinogen fragment E. The E-fragment interacts, in its turn, with the immobilized heavy chain; this interaction is provided for by the lysin binding sites of the plasminogen molecule. The plasmin light chain having no lysin binding sites is specifically absorbed on the immobilized fragment D, whereas the D-fragment--on the immobilized light chain. The elution is caused by arginine or benzamidine; 6-aminohexanoic acid does not affect this interaction. It is assumed that the interaction of plasminogen and plasmin with fibrin is provided for not only by the lysine binding but also by the benzamidine binding sites of the plasminogen molecule.

It was found that fragments E (Mr = 45 000), DH (Mr = 95 000) and DL (Mr = 82 000) decrease the rate of plasmin hydrolysis of fibrin that is not cross-linked with factor XIII; the most effective inhibitor is fragment DL. The Kd values for the interactions of fragments E, DH and DL with plasmin are equal to 0.15, 0.4 and 0.04 microM, respectively.

The heavy and light chains of human plasmin were separated by affinity 1-lysin-cellulose column chromatography. The S-carboxymethyl light chain derivative of human plasmin was imobilized by aminogroups by the insoluble matrices. Insoluble derivatives cf plasmin light chain retain an insignificant proteolytic activity, human plasminogen activator activity and capacity to form complexes with streptokinase. The activator activity of the immobilized light chain-streptokinase complex increases 5-10-fold with respect to the human plasminogen. When adding the light chain preparation to immobilized streptokinase its activator activity relative to the human plasminogen is twice as high. The both complexes: immobilized light chain-streptokinase and light chain-immobilized streptokinase are stable and may be reused for plasminogen activation.

The interaction of Lys-plasminogen and its fragments with fibrinogen fragment E was studied by equilibrium affinity binding. A quantitative analysis of binding parameters revealed two types of binding sites responsible for Lys-plasminogen interaction with the immobilized fragment E, i.e., with a high (Kd = 1.5 x 10(-6) M) and low (Kd = 82 x 10(-6) M) affinity ones. Among plasminogen fragments, only miniplasminogen and KI-3 bound immobilized fragment E and were eluted by epsilon-aminocaproic acid. Hence, two lysine binding sites may be involved in the binding of Lys-plasminogen to fragment E; they are localized in the KI-3 and K5 kringle structures.