[Changes in the fluorescence parameters of lipophilic probes bound to the erythrocyte membrane in cancer patients]. / Ob izmenenii parametrov fluorestsentsii lipofil'nykh zondov, sviazannykh s membranami éritrotsitov krovi onkologicheskikh bol'nykh.

The fluorescence of intensivity of membrane-bound diphenylhexatriene (DFHT) of erythrocytes of the cancer patients is found to increase as compared to that of donors. No reliable differences are detected in a degree of fluorescence polarization of DFHT and pyren excimerization in erythrocyte membranes of cancer patients and donors. The data obtained show that under the development of malignant tumours the structure state of lipid bilayer of erythrocyte membrane does not undergo significant changes. However an increase of the fluorescence intensivity of the membrane-bound DFHT, evidently, is the result of changes in protein-lipid interactions in the membrane.

[Elevated agglutinability of erythrocytes in cancer patients]. / Povyshennaia aggliutinabel'nost' éritrotsitov krovi onkologicheskikh bol'nykh.

Mediated agglutination of erythrocytes was studied in the presence of concanavalin A (Con A). Agglutinability of erythrocytes from cancer patients was found to be higher than that of normal cells as a result of chemical factors present in the blood plasma which transform the cell surface, the number of Con A receptors remaining unchanged. It is concluded that increased agglutinability of erythrocytes from cancer patients is mainly due to a decrease in the negative charge of cells and the appearance of echinocytic forms.

[Various structural-functional characteristics of erythrocyte membranes in malignant growths]. / Nekotorye strukturno-funktsional'nye kharakteristiki membran éritrotsitov pri zlokachestvennom roste.

Changes in the acetylcholinesterase activity, thermal and osmotic stability of erythrocyte membranes of the cancer patients are found as compared with this activity of erythrocyte membranes of donors. No differences were detected in the rate of phosphate anion transfer through the erythrocyte membranes in the examined persons. The data obtained show that the development of malignant tumours is followed by the changes in the structural and functional state of surface components of erythrocyte membranes.

[Thermohemolysis of erythrocytes in the temperature range including physiologic (autohemolysis)]. / Termogemoliz éritrotsitov v diapazone temperatur, vkliuchaiushchem fiziologicheskie (autogemoliz).

The activation energy of thermohemolysis of erythrocytes changes from 36 +/- 5 kcal/mol (35-45 degrees C) to 97 +/- 5 kcal/mol (45-55 degrees C) at the temperature about 45 degrees C in isotonic buffer. The break on Arhenius' plot is preserved also when erythrocytes are placed into plasma. The character of Arhenius' plot is the same when erythrocyte hemoglobin is totally oxidated into methemoglobin by chemical way, though thermal stability of such erythrocytes is decreased. The scheme is presented in which thermohemolysis of erythrocytes occurs by two independent ways: thermodenaturation of hemoglobin (limiting stage of the process when t greater than 45 degrees C) and modification of membrane proteins by hemin, the last being a product of hemoglobin oxidation (limiting stage of the process when t less than 45 degrees C).

[Possible role of spectrin in thermohemolysis of erythrocytes]. / O vozmozhnoi roli spektrina v termogemolize éritrotsitov.

The activation energy of thermodenaturation of erythrocyte spectrin was defined by two different methods as Esp = 218 +/- 4 kcal/mole. This value was more than two times greater than that of thermohemolysis activation energy (Eth = 99 +/- 5 kcal/mole). The conclusion is made that spectrin does not play a significant role in thermohemolysis of erythrocytes.

[Thermohemolysis of erythrocytes]. / Termogemoliz éritrotsitov.

Thermohemolysis kinetic curves of erythrocytes in the temperature interval of 37-75 degrees C in different media and in the course of blood storage were studied. Mechanism of thermohemolysis is proposed. The rate constants of hemolysis stages are introduced. It is shown that these parameters are sensitive to the changes of structural state of erythrocytes.

[Dual-impact mechanism of photosensitized cell damage]. / K voprosu o dvukhudarnom mekhanizme fotosensibilizirovannogo povrezhdeniia kletok.

Dose dependencies of the rate of hematoporphyrin sensitized photolysis of erythrocytes and leucocytes have been investigated. It has been shown that power index of dose dependency for erythrocytes equal 2, while for leucocytes it lies between 1 and 2, suggesting heterogeneity of total leucocyte fraction in photosensitivity.

[Hemolysis of human erythrocytes by hemin. The role of hemin in erythrocyte autohemolysis]. / Hemoliz éritrotsitov cheloveka geminom. Rol' gemina v autogemolize éritrotsitov.

Hemin hemolysis of human erythrocytes at 37 degrees C has been investigated by the kinetic method. It has been observed that hemin affects erythrocytes by two mechanisms, inducing "quick" and "slow" hemolysis. The "quick" hemolysis is completed after the first few minutes. The final level of "quick" hemolysis is a function of relative hemin concentration. It is equal to zero when the latter is smaller than the minimum concentration Cmin = 10(8) molecules of added hemin per cell. The final level of "slow" hemolysis is always 100%. It is suggested that the limiting step of autohemolysis is the membrane proteins oxidation catalyzed by endogenous hemin originating from methaemoglobin during erythrocyte incubation at 37 degrees C.

[Denaturation of hemoglobin--the first stage of erythrocyte thermohemolysis]. / Denaturatsiia gemoglobina--pervaia stadiia termogemoliza éritrotsitov.

Measurements were carried out of the rate constants of erythrocyte thermohemolysis and hemoglobin thermoaggregation in various animal species and also for the man under the action of hemoglobin-modifying factors (CO2, O2, ethanol). It is concluded from the obtained correlation dependences that hemoglobin thermodenaturation initiates erythrocyte thermohemolysis. The identity of the early stages of erythrocyte thermohemolysis and aging is suggested.

[Autohemolysis of human erythrocytes in the temperature range 4-37 C]. / Autogemoliz éritrotsitov cheloveka v oblasti temperatur 4-37 C.

It is shown that the value of activation energy of red blood cells autohemolysis in temperature range of 4 + 37 degrees C is considerably smaller than that at t > 37 degrees C and is about 50 kJ/mol in isotonic saline buffer, pH 7.4. This means that the change of limiting stage of hemolysis occurs at 37 degrees C. It is found that the decreasing of oxygen partial pressure in the medium resulted in marked inhibition of hemolysis without alteration of activation energy in temperature range of 20 divided by 37 degrees C and on the contrary in intensification of hemolysis at t < 20 degrees C. It is concluded that oxidative processes are essential in autohemolysis in temperature range of 20 divided by 37 degrees C and the oxygen stabilizes the structure state of erythrocytes below 20 degrees C.

[Effect of Ca2+ on glucose penetration through the pink ghosts of human erythrocytes]. / Vliianie ionov Ca2+ na proniknovenie gliukozy v rozovye teni éritrotsitov cheloveka.

It has been found that in the presence of millimolar concentrations of calcium added into pink shadows of erythrocytes (C1/2 = 4 mM) the velocity of glucose transport increases three-fold as compared to control shadows. Calcium added from the outside does not affect the glucose transport. Intracellular calcium induces a structural transition in the erythrocyte membrane, which is revealed by spectrin aggregation (electrophoretic data). Study of temperature relationships of glucose transport velocity in the presence of different concentrations of intracellular calcium as well as of the effect of inhibition of transport with phloricin under this condition allows a conclusion that due to Ca-induced transition in the membrane new specialized carriers get involved into glucose transport.

[The search for photosensitive agents specifically binding to human serum albumin]. / Poisk fotochuvstvitel'nykh agentov, spetsificheski sviazyvaiushchikhsia s syvorotochnym al'buminom cheloveka.

Binding of tetrasulfophenylporphyn with human serum albumin was studied by spectral methods. The presence on the protein of one centre of porphyrin binding with high affinity was shown.

[Effect of anesthetics on porphyrin-sensitized photodamage of cells]. / Vliianie anestetikov na sensibiliziruemoe porfirinami fotopovrezhdenie kletok.

The ability of a positively charged local anesthetic dibucain introduced into cell suspension prior to its irradiation to accelerate porphyrin-sensitized photodestruction of different cells is shown. Neutral anesthetics benzocain and ethanol had no such effect. There has been obtained evidence that the dibucain-induced increase in the amount of cell-bound sensitizer plays an essential role in the acceleration of photodestruction.

[Intensification of lipid peroxidation upon damage to cell membranes]. / Intensifikatsiia perekisnogo okisleniia lipidov pri povrezhdenii membran kletok.

It is shown that during sensitized by haematoporphyrin photooxidation accumulation of TBA-active products in destroyed cells (human erythrocytes, rat thymocytes, pig leucocytes) occurs considerably faster than in the intact ones. Similar acceleration is observed in intact erythrocytes after the amount of reduced glutathione in it was decreased. It is supposed that the cause of intensification processes of lipid peroxidation consists in separation of the antioxidant system from the plasma membrane.

[Heterogeneity of pores formed in erythrocyte membrane by lipophilic hemolysins]. / Geterogennost' por, obrazuemykh v membrane éritrotsitov lipofil'nymi gemolitikami.

Concentration dependences of the rate of hemolysis are studied for ascorbic acid, sodium dodecylsulfate, triton X-100, ethyl and butyl alcohols. The double logarithmic plot of this dependence for ascorbic acid presents the straight line with the slope (n) of 2, meaning that two hemolytic molecules are necessary for the formation of one pore in the membrane. Other hemolysins are characterized by the curves with n changing from 2 to 24 as hemolysin concentration increases. The nonlinearity of plots found is considered as a consequence of the heterogeneity of pores, which are formed in the membrane bilayer as hemolysin concentration increases.

[Parameters of hemolysis by sodium dodecyl sulfate as an indicator of the structural states of erythrocyte membranes]. / Parametry gemoliza dodetsilsul'fatom natriia kak indikator strukturnogo sostoianiia membran éritrotsitov.

The relationship between the parameters (percentage and rate) of hemolysis by sodium dodecyl sulfate and the time of incubation of human erythrocyte suspensions in glucose-free medium at 37 degrees C was studied. The polyphasic changes in the parameters were found, which depend on the mode of pretreatment: ATP depletion by iodoacetate, heat denaturation of spectrin, and treatment of cells by valinomycin. It was found that the percentage and rate of detergent hemolysis do not always change in parallel.

[Oxidation of membrane proteins and modification of erythrocyte surface characteristics]. / Okislenie membrannykh belkov i izmenenie poverkhnostnykh svoistv éritrotsitov.

It is shown that the oxidation of membrane protein SH-groups of human erythrocytes by diamide leads to the intensification of vesiculation and the formation on the cell surface of "senescent antigens". These processes were studied during prolonged incubation of erythrocytes at 37 degrees C in the absence of glucose. It was found that the formation of vesicules in ATP-depleted cells correlated with the appearance of "senescent antigens" (r = 0.9, p < 0.01). The oxidation of protein SH-groups takes place at the early stages of vesiculation and strengthening of autologous immunoglobulin binding, indicating that the oxidation of the other groups of membrane proteins plays the leading role in the modification of surface properties.

[Influence of chlorpromazine and temperature on glucose transport in human erythrocyte ghosts]. / Vliianie khlorpromazine i temperatury na transport gliukozy v teniakh éritrotsitov cheloveka.

Glucose transport was determined by oxygen adsorption in solution when glucose was oxidized with glucoseoxidase, injected into erythrocyte ghosts. Temperature dependence of glucose transport velocity shows a break at 20 degrees C, which was described in literature. Small concentrations of chlorpromazine (about 2-10(-5) M) somewhat activates the transport but does not changes its temperature dependence. Higher concentrations of anaesthetics (beginning with 1-10(-4) M) inhibit the transport, decrease the temperature of break and increase the activation energyies of the process both lower and higher of the transition temperature. The change of working velocity of glucose carrier under the action of anaesthetic and temperature is accounted for by structural reconstructions in lipids, which are heterogeneously distributed along the erythrocyte membrane plane.

[Content of intracellular ATP and structural state of proteins in the erythrocyte membrane]. / Socerzhanie vnutrikletochnoi ATF i strukturnoe sostoianie belkov v éritrotsitarnoi membrane.

Effects of depletion and resynthesis of intracellular ATP on the properties of human erythrocytes (deformability, osmotic fragility) and on the structural parameters of their membranes (U. V. fluorescence spectra, protein aggregation) were studied. Incubation of the erythrocytes in the absence of glucose at 37 degrees C was shown to result in a number of consequent alterations: crenating and decrease in deformability of erythrocyte cells--a change in relative contents of membrane proteins--aggregation of membrane proteins and reversible shift of their fluorescence spectra. The evidence is considered in favour of the spectra shift due to dephosphorylation of membrane proteins.

[Effect of chlorpromazine on the relation between temperature and the binding of ANS by human erythrocytes]. / Vliianie khlorpromazina na temperaturnuiu zavisimost' sviazyvaniia ANS s éritrotsitami cheloveka.

It has been shown that under the effect of chlorpromazin (concentration to 2.10(-5) M) breaks observed on Arrhenius graphs of the rate constant of ANS binding with erythrocytes (k) at 28 and 36 degrees C are shifted to the region of low temperatures approximately to a similar interval (14-15 degrees C). The value k measured at 22 degrees C is not changed within the pH range of 5-7. It is concluded that breaks characterised the initial and final stages of temperature transition initiated in the zone of acid phospholipid of membranes.