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Aim    To determine clinical and laboratory parameters associated with in-hospital mortality in patients with acute myocardial infarction and to develop a multifactorial prognostic model of in-hospital mortality.Material and methods    This was a study based on the 2019-2020 Registry of acute coronary syndrome of the Tyumen Cardiology Research Center, a branch of the Tomsk National Research Medical Center. The study included 477 patients with ST-segment elevation acute myocardial infarction (AMI), 617 patients with non-ST segment elevation AMI, and 26 patients with unspecified AMI. In-hospital mortality was 6.0 % (n=67). Clinical and laboratory parameters were assessed on the day of admission. The separation power of indicators associated with in-hospital mortality was determined using a ROC analysis. The data array of each quantitative parameter was converted into a binary variable according to the obtained cut-off thresholds, followed by creation of a multifactorial model for predicting in-hospital mortality using a stepwise analysis with backward inclusion (Wald). The null hypothesis was rejected at p<0.05.Results    The multivariate model for prediction of in-hospital mortality included age (cut-off, 72 years), OR 3.0 (95 % CI: 1.5-5.6); modified shock index (cut-off threshold, 0.87), OR 1.5 (95 % CI: 1.1-2.0); creatine phosphokinase-MB (cut-off threshold, 32.8 U / L), OR 4.1 (95 % CI: 2.2-7.7); hemoglobin (121.5 g / l), OR 1.7 (95 % CI: 1.2-2.3); leukocytes (11.5×109 / l), OR 1.9 (95 % CI: 1.3-2.6); glomerular filtration rate (60.9 ml / min), OR 1.7 (95 % CI: 1.2-2.2); left ventricular ejection fraction (42.5 %), OR 4.1 (95 % CI: 2.0-8.3); and size of myocardial asynergy (32.5 %), OR 2.6 (95 % CI: 1.4-5.0).Conclusions    Independent predictors of in-hospital mortality in AMI are age, modified shock index, creatine phosphokinase-MB, peripheral blood leukocyte count, hemoglobin concentration, left ventricular ejection fraction, size of myocardial asynergy, and glomerular filtration rate. The in-hospital mortality model had a high predictive potential: AUC 0.930 (95 % CI: 0.905-0.954; p <0.001) with a cutoff threshold of 0.15; sensitivity 0.851, and specificity 0.850.

Hemolysis of the sample is a common problem that occurs after blood sampling. The release of hemoglobin in the blood sample changes its colorimetric properties. Present hemoglobin interferes with other biochemical parameters which are determined by colorimetric reaction. In this paper we examined 40 blood samples taken from cows in early lactation. In a sample of 20 cows was no hemolysis, while the samples of 20 cows were hemolyzed. All samples were transported in a stable temperature condition. Heparin was used as anticoagulant. Regression analysis was performed and the correlation between the hemoglobin concentration and the MCHC value (which is an indication of the existence of hemolysis) and blood parameters: glucose, NEFA, BHB, albumin, total protein, urea, AST, ALT, LDH, CK, bilirubin, cholesterol, triglycerides, Na, K, Mg, Ca. The results show that there was no significant difference between the values of the blood biochemical parameters in samples with hemolysis and control samples (there was tendency to increase of albumin, ALT and AST, ot decrease of CK, Ca and Mg in hemolised sample). There was no significant correlation between the degree of hemolysis and values of biochemical parameters (except hemoglobin:albumin and CK, MCHC:ALP and Mg). Regression analysis showed that for each unit of hemoglobin and/or MCHC there was change of glucose, AST, ALT, ALP, LDH, CK, Mg, Ca and bilirubin concentration (for more than 20%), while the other parameters showed slight changes at the level below 5%. The hemolysis in the sample could complicate the analysis of the metabolic profile of cows, but its effect is minimal if the sample is transported in a stable temperature. [ABSTRACT FROM AUTHOR]

In this work, we describe an optimized procedure based on gradual hemolysis for the isolation of hemoglobin derived from bovine slaughterhouse erythrocytes in a membrane bioreactor. The membrane bioreactor system provided high yields of hemoglobin (mainly oxyhemoglobin derivate) and its separation from the empty erythrocyte membranes (ghosts). Ten different concentrations of hypotonic media were assessed from the aspect of the extent of hemolysis, hematocrit values of the erythrocyte suspensions, cell swelling and membrane deformations induced by decreased salt concentration. Effective gradual osmotic hemolysis with an extent of hemolysis of 83% was performed using 35 mM Na-phosphate/ NaCl buffer of pH 7.2-7.4. Under these conditions most of the cell membranes presented the appearance of the normal ghosts under phase contrast microscope. The results show that isolation process yielded predominantly to oxyhemoglobin. Kinetic studies showed that maximal concentration of hemoglobin was reached after 40 min, but the process cycle at which recovery of 83% was achieved lasted for 90 min. [ABSTRACT FROM AUTHOR]

Aim    To test a hypothesis that increased values of red cell distribution width (RDW) in patients with chronic heart failure (CHF) can be related with low exercise tolerance.Material and methods    102 patients were evaluated who had CHF with mid-range and reduced left ventricular ejection fraction (LV EF) without anemia (72% men, mean age 66±10.2 years). Cardiopulmonary stress test (CPST), echocardiography, 6‑min walk test (6MWT), blood count, and measurements of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and serum iron were performed.Results    The average LV EF was 39±8.7 %; the peak oxygen consumption (VO2peak) was 13.7±4.8 ml /kg /min; and the median NT-pro-BNP was 595.3 pg /ml (Q1-3 1443-2401). RDW variables, including the RDW coefficient of variation (RDW-CV) and RDW standard deviation (RDW-SD), were not significantly related with serum iron or hemoglobin concentrations. A one-factor linear regression analysis showed a significant correlation of VO2peak with RDW-SD (р=0.039). A multivariate linear regression analysis with adjustments for LV EF, hemoglobin concentration, and age did not reveal any significant correlation of VO2peak with RDW variables. The distance covered in the 6MWT was significantly associated with RDW-CV both in the one-factor analysis and with adjustments for LV EF, hemoglobin and serum iron concentrations, and age.Conclusion    This study showed that high RDW values in CHF patients without anemia predicted low exercise tolerance regardless of the age, LV systolic function, and hemoglobin and serum iron concentrations. A 16% increase in RDW-CV significantly decreased the likelihood of covering a distance longer than 360 m during 6 min.

Background: A low hemoglobin level in older adults impairs cognitive ability and functional status and associates with risk of falls and fractures, sarcopenia, malnutrition, depression, frailty, and decreased autonomy. Epidemiological data on the anemia prevalence in the geriatric population in our country is not available., Aim: To assess the prevalence of anemia and analyze its associations with geriatric syndromes (GS) in subjects aged 65 years., Materials and Methods: 4308 subjects (30% of men) aged 65107 years, living in 11 regions of the Russian Federation, were examined and divided into age groups (6574 years, 7584 years and 85 years). All the participants underwent a comprehensive geriatric assessment and determined hemoglobin level., Results: The anemia prevalence in older adults was 23.9%. It has been shown that with an increase in age per 1 year, the risk of anemia detection increases by 4%. The incidence of anemia was higher in males than females (28.1% versus 22.1%; p0.001). In most cases, anemia was mild. The results of a comprehensive geriatric assessment show that patients with anemia had lower hand grip force, Barthel Index, the sum of points on Lawton instrumental activities of daily living scale, Mini Nutritional Assessment scale, the Mini-Cog test and higher the sum of points on the Geriatric Depression Scale (GDS-15) and the Age Is No Barrier scale. Patients with anemia were more likely to use hearing aids, absorbent underwear, and assistive devices during movement. Patients with anemia had a higher incidence of all GS, except for orthostatic hypotension and chronic pain syndrome. The presence of GS is associated with an increased risk of anemia by 1.33.4 times., Conclusion: EVKALIPT study obtained domestic data on the prevalence of anemia in older patients and examined its associations with other GS.

Thrombotic complications are the most significant factors determining the prognosis in myeloproliferative neoplasms. Markers for assessing the risk of thrombosis are the number of leukocytes, platelets, hemoglobin level, hematocrit, age, molecular status, history of thrombosis, obesity, arterial hypertension, hyperlipidemia, hereditary or acquired thrombophilia. The pathogenesis of thrombosis in patients with myeloproliferative neoplasms is complex and multifactorial. In most cases, the etiological factor remains unknown. Currently, antiplatelet and anticoagulant therapy is carried out on an individual basis. The algorithm for primary and secondary (after thrombosis) prevention requires development and testing. We present a clinical case of repeated arterial and venous thrombotic complications in a patient with primary myelofibrosis.

Haptoglobin (Hp) is a blood plasma glycoprotein that binds free hemoglobin (Hb) and plays a critical role in tissue protection and the prevention of oxidative damage. In addition, it has a number of regulatory functions. Haptoglobin is an acute phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein synthesized mainly in the liver and lungs and is the subject of research as a potential biomarker of many diseases, including various forms of malignant neoplasms. Haptoglobin has several unique biophysical characteristics. Only in humans, the Hp gene is polymorphic, has three structural alleles that control the synthesis of three major phenotypes of Hp, homozygous Hp1-1 and Hp2-2, and heterozygous Hp2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual's predisposition to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). These are structural transformations (removal of the signal peptide, cutting of the Pre-Hp precursor molecule into two subunits, α and β, limited proteolysis of α-chains, formation of disulfide bonds, multimerization), as well as chemical modifications of α-chains and glycosylation of the β-chain. Glycosylation of the β-chain of haptoglobin at four Asn sites is the most important variable PTM that regulates the structure and function of the glycoprotein. The study of modified oligosaccharides of the Hp β-chain has become the main direction in the study of pathological processes, including malignant neoplasms. Many studies are focused on the identification of PTM and changes in the level of the α2-chain of this protein in pathology. These characteristics of Hp indicate the possibility of the existence of this protein as different proteoforms, probably with different functions. This review is devoted to the description of the structural and functional diversity of Hp and its potential use as a biomarker of various pathologies.

The article discusses pathogenesis and treatment of COVID-19. The authors presented state-of-the-art insight into hemostatic disorders in patients with COVID-19 and clinical recommendations on prevention of thrombosis and thromboembolism in patients infected with SARS-CoV-2. The article discussed in detail a new hypothesis proposed by Chinese physicians about a new component in the pathogenesis of COVID-19, namely, about the effect of SARS-CoV-2 virus on the hemoglobin beta-chain and the formation of a complex with porphyrin, which results in displacement of the iron ion. Thus, hemoglobin loses the capability for transporting oxygen, which aggravates hypoxia and worsens the prognosis. The article stated rules of hemotransfusion safety in the conditions of COVID-19 pandemic.

Morphobiochemical investigations of red blood (space experiment Hematologiya) involved the ISS Russian crew members (increments 6-12). Blood samples were drawn on L-30, at the beginning (FD 6-10) and end (FD 160-190) of orbital flight, shortly after landing (R+0), and on R+7 and R+15. Results of the investigations of red blood metabolism and cell membrane showed that long-duration space flight reduces the hemoglobin level in consequence of, probably, intensive erythropoiesis and premature partial elimination of degraded (possibly old) erythrocytes from circulating blood. High intensity of erythropoises is manifested by an increase in erythropoietin, a decrease in blood iron, and elimination of degraded and old erythrocytes in the course of readaptation to Earth and driven by the growing body demand for oxygen to support muscular work and existence in the gravitational environment in general.

Functional state of the pool of erythrocytes was evaluated in ten essentially healthy male subjects before, during and in 2 months after a series of 15 exposures to normobaric intermittent hypoxia (NIH). The erythrocyte pool dynamics, hemoglobin content, low and highly resistive fractions of erythrocytes were analyzed using a modified acidic histogram technique. It was demonstrated that the erythrocyte pool was either in the state of destruction (concurrent to the NIH exposure) or ensuing persistent improvement of the functional characteristics under study.

The paper deals with two categories of new oxygen-carrying blood substitute solutions (OCBSS), based on a modified hemoglobin (MG) and perfluor-organic carbon emulsion (PCE), and with crystalloid and colloid blood substitutes of the antihypoxic action containing the Crebs' substrate (sodium fumarat). Described are the results of clinical use of Russian OCBSS based on MG (Gelenpol) and on PCE (Perftoran) in 151 patients with hemorrhagic shock and intraoperative blood loss. Both drugs are allowed for medical application in Russia. Gelenpol was administered at 1 to 6 units, perftoran--at 10-15 ml/kg. An improved oxygen status as well as normalization of hemodynamics, microcirculation, rheology, and of blood acid-base balance (ABB) were registered. Gelenpol had a hematosis-stimulating action. The combined use of both drugs or one of them alone in surgery is under discussion. The OCBSS efficiency can be enhanced when they are used jointly with the first Russian infusion antihypoxants containing sodium furmarat, i.e. Mufasol and Polyoxyfumarin. Both of them were shown to normalize the oxidation in tissues, to recover the mitochondrial metabolism in the liver and myocardium and to improve the blood ABB when used in hypovolemic and hypoxic conditions of different etiologies, in substituting for intraoperative blood losses (gastrointestinal hemorrhages), in polytrauma and destructive cholecystitis as well as in preoperative preparations of patients with diffuse peritonitis. The OCBSS preparations and antihypoxants are undoubtedly drugs of choice in emergency infusion-transfusion therapy and in cases of multiple victims from accidents.

A mathematical method based on a complex of capillary blood examinations was proposed and tested for detection of volume and degree of blood loss in trauma of the chest and the abdomen. This method may be used for optimization of intraoperative fluid management. It is very important when bleeding is not only into the serous cavities (blood loss is easy to evaluate during surgery) but also into the intermuscular and interstitial spaces, and also in internal hemorrhage.

Chronic application of various copper concentrations on the skin decreases endogenous levels of iron, zinc, and copper in the serum. Single introduction of disperse copper positively correlates with the level of the oxidation products and Fe/Zn ratio in the liver. Single introduction of ionic and electron-neutral copper induces phased changes in superoxide dismutase and glutathione peroxidase activities. Positive correlation between activities of these enzymes points to efficient control of O2-radicals, dismutation products, and hydroperoxides level by the antioxidant enzymes in animal tissues treated with copper.

Infusions of Helenpole used in 23 patients allowed for a short time to stabilize hemodynamics and to considerably improve the gas-transporting function of blood. The best curative effect in patients with hemorrhagic shock was obtained by means of intravenous jet infusions of the medicine, after stabilization of the hemodynamic indices with the help of an intravenous dropper (80-90 drops/min). The dose of the 1% solution of the medicine was 25-30 ml/kg of the patient's body weight.

Three kits of reagents manufactured by RENAM Research and Production Unit provide the analytical reliability of hemoglobinometry. The kits contain: 1) dry powder transforming agent; 2) four calibration standard solutions of hemoglobin cyanate requiring no dilution; 3) three highly purified stable solutions of hemoglobin (simulating human blood) with attested concentrations of hemoglobin from 50 to 200 g/liter.

Hemoglobin enhances the aggregation of the plague bacillus in fluids (p > 0.99), the proportion of its action on this process being 46.7%. The aggregated forms of the plague bacillus as conglomerates are of greater value in the virulence of the plague bacillus for white mice than are a series of plague bacilli or single microbes, which is an important factor in the mechanism of bacillus transmission. Block is an aggregated status of the plague bacillus in the gizzard of an effective vector.

Blood serum levels of extraerythrocytic hemoglobin (EEHb) were measured by the hemoglobin cyanide method in 71 patients with acute viral hepatitis B over the course of the disease. The mean values of this parameter in 30 normal subjects were found to be 0.67 +/- 0.03 g/l. In the patients in the acute period of hepatitis (weeks 1-2 of jaundice) EEHb levels were drastically elevated, particularly so in grave cases (2.36 +/- 0.22 g/l), though even in benign cases this value surpassed the norm twofold. As the jaundice regressed, EEHb levels somewhat lowered, though persisted rather high. EEHb content normalized by discharge from hospital only in the patients with the mild form of acute viral hepatitis B. The studies have revealed the prognostic value of this parameter that reflects the level of intravascular hemolysis. The authors suggest the major role of elevated red cell hemolysis in the pathogenesis of the increase of free bilirubin level in the blood in acute viral hepatitis B.

A study was made of bovine hemoglobin polymer obtained by a new method: intraerythrocytic polymerization of hemoglobin followed by isolation of hemoglobin polymer. The polymer obtained had weighted mean and numerical average molecular mass of 388 kD and 134 kD, respectively, P 32 mm Hg, arteriovenous difference 5.1 vol%, Hill's coefficient 2.14, oxygen output rate constant 55 sec, and it retained its activity during long-term storage. Its solution in a concentration of 9-10 g/dl has a viscosity of 2.34, and an oncotic pressure of 240 mm water. Bovine hemoglobin polymer is nontoxic and capable of long-term circulation in the blood. Its safety and clinical effectiveness should be studied in an extended biological experiment.

The effects of some components of the blood on times of spin-grade and spin-spin relaxation of water protons using the method of proton magnetic relaxation. Equations of correlation for the content of hemoglobin and proteins in saline was obtained. A model for the relaxation measurements of the whole blood was constructed.

Hemodynamic and gas-transporting properties of the chemically modified hemoglobin solution have been studied on the model of hemorrhagic shock in dog. It has been shown that the polymerized hemoglobin solution exerts the hemodynamic action just as the plasma substitute "polyglucin" does. However, in contrast to the latter, polyhemoglobin circulating in the vascular bed for a prolonged period of time increases the blood oxygen capacity and oxygen delivery to tissues with the resultant increase in body total oxygen taking-up.

The efficacy of the modified polyhemoglobin suggested as an artificial oxygen transporting substitute was estimated in the model of extreme hemodilution in dogs. It was shown that O2 consumption in dogs had been supported on the normal level during 4 hours after total exchange transfusion with the polyhemoglobin solution. Index of hemodynamics testifies that preparation has hemodynamics action. The conclusion was made that this modified polyhemoglobin has been effective O2 carrying blood substitute.

The circadian rhythms of the erythrocytes, hemoglobin and leucocytes concentration in the peripheral blood in dogs in winter and the effect of the eleutherococcus multi-injected at different periods of the day, were studied. The changes in the parameters of the studied biorhythms indices were observed only in the after dinner-injected animals, they being marked by the evident increase of the mesor and amplitude, acrophase shift by 1-2 hours by the beginning of the twenty-four hours.

Eight fractions of rat hemoglobin obtained by electrophoresis in polyacrylamide gel were studied. Having used parachloromercuric benzoate (PChMB) and 5,5-dithio-bis (2-nitrobenzoic acid) it was established that fractions of 3 and 3a carboxyhemoglobin contain 6 available SH-groups and the rest one (1, 2, 2a, 4, 5, 6) about 4 SH-groups. In all fractions only 2 masked SH-groups are found. A problem is discussed on SH-groups localization in the polypeptide chains of certain hemoglobin fractions in rats.

Before exposure of man to hyperbaric hyperoxia the blood plasma possessed marked erythropoietic activity. Erythropoietins disappeared completely and erythropoiesis inhibitors appeared in the plasma of persons untrained to hyperbaric hyperoxia after a 24-hour exposure to hyperoxic conditions (25% of oxygen in the inhaled air) in the high pressure chamber corresponding to the depth of 63 metres. A reduction of the peripheral red blood indices was observed by that time.

Absorption and magnetic circular dichroism spectra of nonequilibrium states of hemoglobin and its derivatives formed by reduction oxidased forms of hemoproteins by thermalysed electrons at 77 degrees K were studied. Mixtures of low spin and high spin ferroforms were observed for nonequilibrium hemoglobin and its complexes with inosithexaphosphate and fluorine. The content of the high spin form increasing as follows: hemoglobin, complex with inosithexaphosphate, complex with fluorine. Only low spin forms were found for cyanide and azide complexes of hemoglobin reduced at low temperature. The spectral differences of nonequilibrium low spin ferroforms were supposed to be due to the presence of different ligands in the coordination sphere of the heme iron. The alpha-band splitting was observed for the nonequilibrium imidazole complex of hemoglobin. This effect was explained by a lowe-ring of the active centre's symmetry. The temperature relaxation of all nonequilibrium systems was investigated.

Change of human hemoglobin equilibrium with CO was studied during short-term illumination. The change of the saturation curve of Hb is discussed taking into account an increase of free gase concentration in solution accompaniing the photodissociation.

Theoretical conformational analysis was carried out for a mixed disulfide of hemoglobin with glutathione. The conformational mobility of the beta-subunit C-terminal fragment in methemoglobin and deoxyhemoglobin either with free or glutathione-blocked reactive SH-groups was examined. The most stable conformations of the mixed disulfide were delineated. Its spatial structure was shown to be dependent on the hemoglobin state prior to the S-S bond formation: a disulfide made with deoxyhemoglobin had more closely interwoven hemoglobin and glutathione chains than the methemoglobin-derived disulfide. However, in both cases disulfide formation brought about the alterations in the spatial structure of hemoglobin as well as glutathione. The changes in the hemoglobin biochemical properties accompanying the association with glutathione were rationalized in the frames of the mixed disulfide structural analysis.

The shape of red and white ghosts and the ultrastructure of the inner perimembrane layers have been studied. The cytoplasmic perimembrane layer is proved to have a fibrous lattice-like structure. The ghosts with a great amount of hemoglobin have ellipsoid or deformed circular shapes. White, hemoglobin-free ghosts have an irregular shape. After their resealing with a following incubation in an isoosmostic (300 imomole) succarose solution they assume a shape of narrow arcous profiles containing fibrous lattice-like material. The organization of this material is variable and depends on the degree of ghost hydration. It is proposed that this spectrin-like material may account for the stability of the long-range membrane organization.

The rates of proteolytic breakdown for native human hemoglobin (Hb) in CNmet-and oxy-forms, for isolated native alpha- and beta-chains of human Hb with deprotected SH-groups and for apo-Hb--globin at constant temperature 20 degrees as well as for metHb and globin in the temperature range 4-25 degrees were studied. The proteolysis of oxy-forms of proteins was performed in the presence of CN- to prevent the appearance in solution of quickly splitted aqua and hydroxy met-forms. Pepsin (at pH 5.5), trypsin (at pH 7.0 and 8.5) and protease VI (pronase) (at pH 7.0 and 8.5) were used as proteases. The rate of proteolysis was registered simultaneously by proteolysate precipitation in concentrated salt solutions (to determine the content of the native form), by precipitation in aqueous solution of trichloroacetic or perchloric acid and by colouring the terminal NH2-groups by ninhidrin in the total proteolysate. For most cases the data of all the three independent methods fell on a single kinetic curve, each pair protein--protease being represented by their individual curves. Therefore the breakdown of all the protein studied possesses a burst-like ("one-by-one", "all-or-none") character. The protein resistance to the attack by proteolytic enzymes increases in the following order: globin less than oxy-alpha-chain less than metHb less than oxy-beta-chain less than HbO2 congruent to CNmetHb. The use of control repeated proteolysis has made it possible to prove that differences in the rate of proteolytic degradation are not the consequence of spontaneous denaturation of the least unstable forms of proteins in the course of proteolytic reaction but are predetermined by the conformational state of the native macromolecule.

By ion-exchange chromatography the composition of the fibrinolytic enzyme from Aspergillus terricola-terrilytine-was studied. The preparation contained five components that differed in their substrate specificity. Three of the components and proteolytic and fibrinolytic activities. The isolated fractions were examined with respect to their pH stability, pH optima (casein, hemoglobin and fibrin used as substrates), fibrinolytic and fibrinohenolytic activities.

The paper deals with the results obtained while measuring the surface presssure of hemoglobin monolayers containing diethylstilbestrol. It is shown that insignificant additions of diethylstilbestrol change the shape of the surface hemoglobin pressure isoterm. The addition of diethylstilbestrol to hemoglobin causes a considerable increase in the limiting value of the area corresponding to the substance mass unit in the monolayer. The time passed from the moment of components mixing till deposing the substance upon the interphase affects the value of the area.

The temperature dependences of magnetic circular dichroism (MCD) spectra of the high-spin fluoride complexes of metmyoglobin, methemoglobin and horse-radish ferriperoxidase have been studied and analysed in spectral region 250-1100 nm at temperatures from 2 to 300 K. Upon lowering of the temperature the increase of the MCD intensity was observed over all spectral regions studied, indicating the presence of the so called C-type effects. In contrast to other paramagnetic hemoproteins studied previously the significant changes of the shape of MCD spectra of fluoride complexes in the near UV B (pi--pi*)-band (Soret band) was observed at the lowest temperatures. The changes are explained by the superposition of effects of two types: the usual C-type effects which have the shape of absorption dispersion and of the derivative shape CA-type effects. The CA-type effects in the Soret band were analysed in terms of the theoretical model suggested previously. The data are in qualitative agreement with the prediction of the model. New information on the energies of the 4E and 4A2 excited states of the heme iron, on the orbital contribution into ground state paramagnetism and on the value of the pi--d pi-splitting, typical for B(pi--pi*)-state and ground Kramers doublet, were obtained on the basis of quantitative analysis of the MCD temperature dependences. The parameter D of zero-field splitting was estimated from MCD spectra and its value (6 cm-1) agrees well with that obtained by other methods.

The computer model of folding of two alpha-helices of globular proteins was developed. The radicals of amino acids were approximated by spheres with centers located in C beta-atoms. The functional of energy took into account the hydrophobic interactions of alpha-helices, electrostatic contacts of charged and polar side groups of amino acid, Van der Waals' interactions. The conformations with minimum energies of two-helical superstructures G--H from alpha- and beta-chains of horse hemoglobin, sperm whale myoglobin, and erythrocruorin were computed. They have mean deviation 0.7--1.8 A from native conformations of these proteins. Hence, at the self-organization process alpha-helices firstly are "roughly" oriented by hydrophobic interactions, but the choice of stable conformation occurs by Van der Waals' and electrostatic interactions. On this stage the low-energy conformation becomes "frozen" and cannot be significantly rearranged later. The mutual orientation of secondary protein structures are determined mainly by amino acid radical volumes, their hydrophobicity and charge.