[Levels of bone mineral matrix organization and the mechanisms determining parameters of its formation].

Authors suggest to regard bone mineral matrix as the four-level structure. The first level is represented by an internal structure of a mineral, the second--by mineral morphological structure, the third--by coplanar association of minerals, and the fourth--by macroassociation of minerals in a single complex inside each bone. The most probable mechanisms determining stability of reproduction of mineral matrix parameters on each of these levels are shown. As a result of their functioning, the variants of bone mineral matrix structures are formed that are the programmed reflection of specificity of the given site of organic structures.

[The effects of divalent cations on the fibrin clot formation and its lysis].

Hemocoagulation is a Ca(2+)-dependent process, and we suppose that other bivalent cations (BC) can also influence this system. The effects of some BC (Ca2+, Fe2+, Zn2+, Cd2+, Co2+ and Ni2+) on thrombin-induced plasma clotting and clot lysis caused by streptokinase have been studied. All BC studied, except Fe2+, maintained the formation of fibrin clot followed by its lysis. In the presence of BC the coagulation part of the turbidimetry curve changed in a dose-dependen manner and was characterized by: (1) the decrease of the induction period which seems to be due to thrombin activation or accelerating fibrin self-association; (2) the elevation of the maximal optical density of the fibrin clot and the velocity of its achievement. The fibrinolytic part of the curve was characterized by the optical density downfall acceleration at low Co2+, Cd2+, Zn2+ and Ni2+ concentrations but marked delay of the process at BC higher concentrations. So, ions of Co2+, Cd2+, Zn2+ and Ni2+ but not Fe2+ significantly influence the dynamics of thrombin-induced clot formation and optical clot characteristics. At different ion concentrations BC may activate or inhibit fibrinolysis.

[Turbidimetric analysis of fibrin polymerization in the plasma]. / Turbidimetricheskii analiz polimerizatsii fibrina v plazme krovi.

The turbidimetrical assay of thrombin-induced plasma coagulation provides a possibility to estimate both stages of fibrinogen-fibrin conversion. The initial one, which proceeds without any change of turbidity, reflects the process of protofibril formation, and the second stage of lateral aggregation, is characterized by the rise of turbidity. The influence of heparin, alga (Laminaria digitata) aqueons extracts, and collagenase on the indices of the turbidity-time curve has been studied. It was established that the alga extracts possessed the powerful heparin-like anticoagulant activity. The both agents influenced the first stage of the turbidity-time curve, suppressing protofibril formation, which reflects the thrombin inhibition. Nevertheless, they differed in their mode of dose-dependence. While the time of protofibril formation was direct proportional to the alga extract concentration, it was rising more intensively with heparin dose elevation. Plasma pre incubation with alga extract or heparin did not influence their action. Treatment with plasma collagenase changed only the second stage of the coagulation curve. It inhibited the process of protofibril lateral aggregation in the direct proportional manner. It must be due to fibrin digestion by the enzyme. We propose that fibrin cleavage by collagenase occurred out of the thrombin action sites, because the velocity of protofibril accumulation stayed unchanged. Our data illustrate the usefulness of the turbidimetrical analysis in the studies of the agents' action mechanisms on blood coagulation, in conditions close to physiological ones.

[Characteristics of the acute phase reaction in humans with various types of autonomic nervous system regulation during simulated hyperthermia]. / Osobennosti ostrofaznogo otveta u liudei s razlichnym tipom reguliatsii vegetativnoi nervnoi sistemy pri modelirovannoi gipertermii.

Depending on the type of autonomous regulation, differences in basic levels of interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF alpha) were revealed under conditions of hyperthermia in healthy subjects aged 19-21. A parasympathetic type of autonomous regulation corresponded to higher initial levels of proinflammatory cytokinesis, whereas a dominating sympathetic type corresponded to lower levels of the IL-1 beta and TNF alpha. The subjects with the latter type of regulation revealed an increase in the IL-1 beta TNF alpha combined with a higher heat tolerance. The subjects with the former type of regulation revealed a lower heat tolerance. The increase in the alpha2-macroglobulin appeared to be a most typical acute phase response of the human body to hyperthermia.

[Hydrogen peroxide--a marker for respiratory tract inflammation in patients with bronchial asthma]. / Perekis' vodoroda kak marker vospaleniia dykhatel'nykh putei u bol'nykh bronkhial'noi astmoi.

AIM: To test H2O2 as a marker of respiratory tract inflammation in patients with bronchial asthma (BA). MATERIAL AND METHODS: The study entered 70 patients (20 males and 50 females) with atopic asthma (AA) aged 18 to 62 years (mean age 32.6 years). H2O2 concentration in the expired air (CEA) was determined spectrophotometrically (Gallati & Pracht, 1985), content of eosinophilic cationic protein (ECP) in blood--with radioimmunoassay kits (Pharmacia & Upjohn, Sweden). Forced expiratory volume per 1 second (FEV1) was used for assessment of severity of bronchial obstruction. Bronchial hyperreactivity was studied by means of the histamine bronchoprovocative test. RESULTS: H2O2 in CEA in BA patients was higher than in healthy subjects (0.127 +/- 0.010 microm/l vs 0.024 +/- 0.004 microm/l). H2O2 concentration significantly correlates with FEV1 (r = -0.449; p < 0.001), bronchial hyperreactivity to histamine (rs = -0.382; p < 0.05) and ECP in blood plasma(r = 0.625; p < 0.01). CONCLUSION: It was proved possible to use H2O2 in CEA for evaluation of respiratory inflammation in BA patients.

[Threshold mechanism of the control of cascade proteolysis]. / Porogovyi mekhanizm kontrolia kaskadnogo proteoliza.

The immune lysis rate of erythrocytes vs. the concentration of particular complement components was studied. It was found that in the presence of component C1 (but not C3) and factors B and D, the cells undergo lysis after the concentration of these compounds exceeds a "threshold" value. The threshold molar concentrations of factors D and B exceeded 5- and 20-fold, respectively, that of component C1. The multiplicity and different capacities of the thresholds allow the fragmentary activation of cascade proteolysis at stretches between neighboring thresholds without the total realization of the final effect of the system (cell lysis, clot formation, etc.). The resulting peptideby-products (bypass peptides) may possess their own biological activity. It is the generation of various bioregulators that appears to be the main function of the cascade proteolytic systems functioning in the subthreshold regime.

[Activity of the complement system in blood serum of dogs after treatment of acute necrotic pancreatitis with boiled pancreatic juice]. / Aktivnost' sistemy komplementa syvorotki krovi u sobak pri lechenii ostrogo nekroticheskogo pankreatita prokipiachennym podzheludochnym sokom.

The investigations were conducted on 14 dogs. To assess the blood serum complement system, the erythrocyte lytic rate of a rabbit (RE) and a sheep (SE), the hemolytic capacity of the complement system against rabbit (RH) and sheep (SH) was measured. In acute necrotic pancreatitis, no changes in SE and SH were revealed either in the control and experimental animals. RH was decreased both in the control and experimental animals. Lower RE was found only in the controls untreated with boiled pancreatic juice. It can be suggested that in the controls the decrease in the parameter RE that characterized the activity of the complement system is associated with the emergence of complement inhibitors, which did not take place when the boiled juice was given. Preventing the complement inhibitors from forming, pancreatic juice is likely to be able to diminish the body's endogenous intoxication which is a cause of death in acute necrotic pancreatitis. This may be suggested by the higher survival of the animals and lower relative extent of pancreatic acinar tissue necrosis after boiled pancreatic juice treatment of acute necrotic pancreatitis.

[Structure and properties of extracellular proteins regulating the proteolytic phase of complement activation]. / Stroenie i svoistva vnekletochnykh belkov-reguliatorov proteoliticheskoi fazy aktivatsii komplementa.

The structure and biochemical properties of the major soluble regulatory proteins of the complement, including the CI-inhibitor, factors I, H, and J, properdin, the C4-binding protein and other protein components, are reviewed. Three types of the proteolytic complement cascade regulation by proteins are envisaged: the first one involves the inhibition of complement proteases, the second one is based on proteolytic degradation of complement activation products and the third one includes the regulation of stability of complement protein complexes. The main functional role of humoral regulatory proteins consists in the limitation of the proteolytic cascade.

[Gas chromatographic method for determining esterase activity of proteolytic enzymes using continuous gas extraction of the volatile product]. / Gazokhromatograficheskii sposob opredeleniia ésteraznoi aktivnosti proteoliticheskikh fermentov s pomoshch'iu nepreryvnoi gazovoi ékstraktsii letuchego podukta.

A new procedure was developed for estimating the esterase activity of proteolytic enzymes by using CIS subcomponent of complement and N-alpha-benzoyl-L-arginine ethyl ester as a substrate. In contrast to other methods, which used static variants of gas chromatographic vapour-phase analysis for registration of the volatile reaction product alcohol, the procedure involved steady gas extraction of the volatile product in the gas stream over the incubation mixture. This method enabled to obtain a kinetic curve during one experiment as well as to elevate the accuracy of enzymatic activity estimation.

[Concentration-functional interrelationships in the human alternative complement activation pathway]. / Kontsentratsionno-funktsional'nye vzaimootnosheniia v al'ternativnom puti aktivatsii komplementa cheloveka.

The dependence of the rate of human complement mediated lysis of rabbit erythrocytes on concentrations of factors B and D of the alternative pathway is characterized by saturation kinetics. At low B and D concentrations no lysis occurs until certain "threshold" concentrations of the respective factor are reached. The type of dependence of the hemolysis rates on the C3 concentration is wavelike, i.e., at definite C3 concentrations the erythrocyte lysis is inhibited. It has been supposed that C3 not only mediates the complement-dependent hemolysis but also plays a prominent role in the self-regulation of this process.

[The action of karbogal on the complement system under model conditions and in an animal experiment]. / Vozdeistvie karbogala na sistemu komplementa v model'nykh usloviiakh i v éksperimente na zhivotnykh.

The influence of dimethylperfluorocyclohexane (carbogal) on the hemolytic activity of human blood serum complement was studied in vitro. It has been show that different effects of carbogol on the complement depend on the serum lipid composition. Endotracheal administration of carbogal to rats results in a significant reduction of complement activity in the animal's blood. Significant changes in the hemolytic activity of the complement recorded 21 days after the endotracheal administration of the compound are, probably, associated with the complement depletion after its activation by carbogal particles or with disorders in the complement component synthesis by macrophages.

Molecular heterogeneity of plasma superoxide dismutase.

A method was worked out that helped us to isolate superoxide dismutase (SOD) from human blood plasma. The change of enzyme's activity was shown depending on the period of SOD storage. Changes in activity were observed in storing protein after gel filtration. The activity of purified enzyme was half as much after 24 h storage and remained constant for a long period of time (5 mo). The change of SOD activity was found to be connected with a modification of its structure. The storage of enzyme's solution during 3 1/2 mo is accompanied by the lowering of protein molecular mass from 53,000 Da to 34,000 Da. The inhibitors of proteinases--phenyl-methylsulfonyl fluoride (PMSF) and alpha 2-macroglobulin--showed no protective effects on purified SOD. That's why it was possible to say that the lowering of protein molecular mass didn't connect with a specific proteolysis. An oxidative modification of SOD structure is under discussion now. The modification is most probably caused by oxidative destruction of aminoacid residues that are located outside the protein active centre.

[The effect of plasmin on complement in human blood serum]. / Vliianie plazmina na komplement syvorotki krovi cheloveka.

Plasma exhibited the dose-dependent inactivating effect on human blood serum hemolytic complement both in classic and alternative pathways. Negative correlation (r = -0.8) was found between the rate of complement inactivation and content of C3 component. Plasmin appears to hydrolyze mainly the C3 component of complement as a result of which hemolytic activity of complement is decreased.

[Antitrypsin effects of alpha-2-macroglobulin]. / Antitripsinovye éffekty alpha-2-makroglobulina.

Purified preparations of alpha 2-macroglobulin were preincubated with bovine trypsin at various molar ratios. Effects of the preincubation were measured before and after addition of soybean trypsin inhibitor in excess if N-benz-L-arg-p-nitroanilide was used as a substrate. Two types of interaction between alpha 2-macroglobulin and trypsin were detected. One of them was carried out depending on the "trap" hypothesis, another type of the interaction led to the enzyme loss of both proteolytic activity and its ability to hydrolyze the low molecular substrate. The data obtained suggest that various molecular forms of native alpha 2-macroglobulin were responsible for these types of interaction.

[Macrophage activation induced by a synthetic antioxidant]. / Aktivatsiia makrofagov pod vliianiem sinteticheskogo antioksidanta.

The effect of a synthetic antioxidant 2-tretbutyl-3-hydroxypyridine (TBHP) on the function of murine peritoneal macrophages (MP) has been studied. A direct contact of TBHP with MP in vitro increased the activity of a key enzyme of glucose monophosphate graft--glucose-6-phosphate dehydrogenase and the proportion of flattened MP. as compared to the control. Upon intraperitoneal MP injection the number of MP's in the abdominal cavity of mice increased. They differed from control MP's in enhanced flattening and phagocytosis. In mice with preinduced defect of abdominal clearance TBHP contributed to the recovery of the normal level of antibacterial protection. In all the in vitro and in vivo tests studying its activating effect on MP, the synthetic antioxidant was not inferior to the standard MP activator--bacterial lipopolysaccharide.

[Products of the proteolytic effect of cathepsin on various protein substrates]. / Issledovanie produktov proteoliticheskogo deistviia katepsina na nekotorye belkovye substraty.

Cathepsin B was shown to hydrolyze in calf thymus histones not only the peptide bonds involving alkaline amino acid residues but also the bonds involving aromatic amino acid residues. Thermo- and acid stable inhibitors of cysteine proteinases were found among the products of albumin hydrolysis by means of these enzymes as well as in the products of the enzymes autolysis.

[Endogenous inhibitor of cysteine proteases from the human kidney]. / Endogennyi ingibitor tsisteinovykh proteinaz iz pochki cheloveka.

A thermo- and acid stable inhibitor of cysteine proteinases was isolated from the human kidney by successive procedures--acid fractionation, gel-filtration on Sephadex G-75, affinity chromatography on papain-sepharose. The final purification factor was 650 fold. The inhibitor molecular weight was equal to 12 kDa. The values of Ki measured by different methods are (7.9-9.4) X 10(-4) M for papain and (7.1-8.0) X 10(-10) M for purified human kidney cathepsin B. In experiments with papain, inhibitor kass and kd were 1.1 X 10(6) M-1 s-1 and 9.0 X 10(-4) s-1, respectively. The inhibitor did not influence the trypsin activity, its properties being similar to those of related thermo- and acid-stable inhibitors from other human and animal tissues.