[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.

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.

[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.

[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.

[Leukotrienes]. / Leikotrieny.

The paper deals with the structure and nomenclature, distribution, metabolism and biological role of leukotrienes, a group of derivatives of eicosanic acids, in the human and animal organism. Leukotrienes can cause contraction of smooth muscles, stimulate the function of leukocytes, and affect the permeability of vessels and arterial pressure. The participation of these substances in the inflammatory processes and allergic reactions is discussed.

[Activity of cathepsin B and serine trypsin-like peptide hydrolases in human kidney extracts]. / Aktivnost' katepsina B i serinovykh tripsinpodobnykh peptidgidrolaz v ékstraktakh pochki cheloveka.

A potentiality to use the available substrates BAPNA and BAME was studied in estimation of activities of cathepsin B and other trypsin-like hydrolases in extracts of human kidney cortex. In these extracts the BAME-hydrolyzing activity of cathepsin B was difficult if impossible to detect due to high level of attendant non-thiol esterases. At the same time, BAPNA might be used for this purpose as a substrate in estimation of cathepsin B- and trypsin-like peptide hydrolase activities in biopsies of human kidney.

[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.

[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.

[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.

[Eznzymatic conversions of ortho-nitrophenyl organophosphorus compounds in the tissues of white rats]. / Fermentativnye prevrashcheniia ortonitrofenil'nykh fosfororganicheskikh soedinenii v tkaniakh belykh krys

In homogenates of rat tissues hydrolysis of O-heptyl-O-orthonitrophenylmethyl phosphonate, O-pentyl-O-orthonitrophenylmethyl phosphonate and O-heptyl-O-isopentyl-O-orthonitrophenylphosphate was studied. Hydrolysis of the preparation was shown to be carried out mainly in liver tissue and slso in kidney and blood serum. The substances studied were cleaved only at the bond P-O-aryl. The structure of orthonitrophenyl phosphoorganic substances exhibited the distinct effect on Km and on the maximal rates of the enzymatic hydrolysis. In all the tisses studied O-heptyl-O-orthonitrophenylmethyl phosphonate was hydrolyzed with maximal rate.

[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.

[Diagnostic value of determining endogenous proteinase inhibitors in cancer patients]. / Diagnosticheskaia tsennost' opredeleniia éndogennykh ingibitorov proteinaz u onkologicheskikh bol'nykh.

Patients with stage III and IV cancers of different sites revealed a 47-76% increase in serum total antitrypsinic activity. A mean 40% increase was observed in cases of inflammatory pathology. Both study groups demonstrated raised alpha 1-antitrypsin levels, while that of alpha 2-macroglobulin did not show any significant changes. The level of alpha 1-antitrypsin accounted for 89 and 83% of total antitrypsinic activity in cases of inflammation and controls, respectively, while in cancer patients this index was significantly lower (70%). The diagnostic value of total antitrypsinic activity appeared to be higher than that of alpha 1-antitrypsin level determination. It is inferred that, apart from alpha 1-antitrypsin, malignant growth is associated with raised levels of more specific endogenous proteinase inhibitors, except alpha 2-macroglobulin.

[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.

[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.

[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.

[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.