PROTECTION OF RED BLOOD CELLS DURING CARDIOPULMONARY BYPASS

Aim. This study was aimed at developing biocompatibility of extracorporeal components due to the use of «adaptation composition» (AdC), reducing the negative impact of perfusion on the state of red blood cell due to the use of fructose-1,6-diphosphate (FDP) to decrease intraoperative hemolysis and tissue hypoxia. Material and methods. The study included 225 patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The first group included patients who underwent surgery with the treatment of an extracorporeal circuit by AdC, the second group included patients who were administered the drug with the active substance FDP, the third group was the control group. The oxygenator was treated with AdC and PDF was administrated according to the protocol. Patient blood was sampling for complete blood cell count (CBC) and blood smears were at 4 stages of surgery: before CPB, at 10 min. CPB-time, at 60 min. CPB-time (rewarming stage) and after separation from CPB. Several parameters were studied: plasma free hemoglobin (plfHb), the erythrocytes osmotic, mechanical resistance of erythrocytes, erythrocyte membrane permeability (EMP), acid hemolysis, the blood smears were stained according to Pappenheim. Results. The best erythrocyte indices, hemolysis, osmotic, mechanical, acid, urea resistance of erythrocytes were observed in the groups where fructose-1,6-diphosphate and «adaptation composition» were used. At the preoperative stage, hypophosphatemia was detected in 16.8% out of 225 patients and 26.6% out of 225 patients have a clear tendency to ones. After CPB, there was no hypophosphatemia in the group where fructose-1,6-diphosphate was administered. The higher peripheralization of reticulocytes, echinocytes, and spherocytes was observed in the control group after perfusion. Conclusion. The use of AdC and FDP during CPB helps to reduce hemolysis and the better state of erythrocytes. Cardiopulmonary bypass (CPB) can negatively affect the state of red blood cell. The effect of fructose-1,6-diphosphate and «adaptation composition» on the state of erythrocytes during perfusion was studied.

METHOD OF ERYTHROCYTE PROTECTION IN URGENT CARDIAC SURGERY

Aim: The use of a simple, safe and convenient method of treatment extracorporeal circuit with «adaptation composition » (AdC) for the reduction of negative impact on the state of erythrocytes and tissue hypoxia. Material and methods: The research included 150 patients. They were divided into two groups. The first group included patients who underwent surgery with the treatment of an extracorporeal circuit by AdC, the second group was the control group. Сomplete blood count parameters, plasma free hemoglobin concentration, erythrocyte mechanical and osmotic resistance, erythrocyte membrane permeability and acid hemolysis were studied. Results: Use of AdC prevents adsorption the blood cells on the surface of the extracorporeal circuit and protects the erythrocytes during cardiopulmonary bypass in urgent cardiac surgery. Conclusions: The treatment of oxygenator with AdC reduces the negative influence СРВ on state of RBC. Membranes of erythrocytes were more resistant to traumatic factors in the group with AdC.

The effect of sorbents on the serum levels of copper, iron and their transporting proteins at alcohol intoxication

Aim. Evaluate the effect of sorbents on erythrocyte membrane permeability and serum levels of copper, iron and their transporting proteins at acute ethanol intoxication. Methods. The study was performed on 94 rats. Acute alcohol intoxication was simulated on intact animals and in animals with prior artificial alcohol abuse. Acute ethanol intoxication was caused by intragastric administration of 40% ethanol at a dose of 0.5 of median lethal dose. Polysorb, Litovit, and Sapropel sorbents were administered at a dose of 3000 mg/kg 30 minutes after ethanol administration. permeability of erythrocyte membrane, serum levels of copper, iron, ceruloplasmin and transferrin were measured by spectrophotometry. Results. Levels of copper and iron in rat serum and erythrocyte membrane permeability significantly dropped compared to the control level at acute ethanol intoxication, ceruloplasmin level raised by 1.5 times, transferrin level did not change significantly. At acute ethanol intoxication in animals with prior artificial alcohol abuse, copper and iron levels and erythrocyte membrane permeability remained low, ceruloplasmin level remained high, transferrin level was decreased for 2 times. All sorbents were able to compensate the serum levels of copper, iron and ceruloplasmin in animals with prior artificial alcohol abuse, and Litovit and Polysorb also influenced on transferrin level. Conclusion. Compensatory effect of Polysorb, Litovit, and Sapropel on the serum levels of ceruloplasmin, copper, iron and transferrin and on erythrocyte membrane permeability was discovered at acute ethanol intoxication in animals with prior artificial alcohol abuse.

Influence of triphenyltetradecylphosphonium bromide on the Na+-Li+- countertransport rate in the erythrocyte membrane in patients with genetically different permeability of cell membranes to sodium

Aim. To study the influence of triphenyltetradecylphosphonium bromide [(PPh)3P+C14H29] Br- on the cell membranes permeability to Na+ by determining the rate of Na+-Li+-counter transport in erythrocyte membrane depending on it’s variable initial condition. Methods. Blood samples of 10 healthy volunteers with different Na+-Li+-counter transport rate distribution in erythrocyte membrane were analyzed: I quartile (5 subjects) - low permeability, III quartile (5 subjects) - moderately high permeability. Results. Na+-Li+-counter transport rate change in erythrocyte membrane under the influence of triphenyltetradecylphosphonium bromide depends on genetically determined initial membrane permeability. In subjects belonging to III quartile of Na+-Li+-counter transport the initial membrane permeability is high, and after administration of 0.001 and 0.005 μM concentrations of [(PPh)3P+C14H29] Br- membrane permeability to Na+ increased. In subjects belonging to I quartile of Na+-Li+-counter transport (low initial permeability) [(PPh)3P+C14H29] Br- did not alter membrane permeability to Na+. Conclusion. Triphenyltetradecylphosphonium bromide increases erythrocyte membrane permeability to Na+ in subjects belonging to III quartile of Na+-Li+-counter transport and dose not influence subjects belonging to I quartile of Na+-Li+-counter transport.

Changes in erythrocyte membrane permeability induced by verapamil, chlorpromazine, and their combinations with amphotericin B

Changes in erythrocyte membrane permeability induced by verapamil, chlorpromazine, and their combinations with amphotericin BHemolysis induced by 2 amphipathic agents, verapamil and chlorpromazine, was investigated in various incubation conditions. Changes in absorbance of erythrocyte suspension were monitored by absorption spectrophotometry at a wavelength of 590 nm. The hemolysis induced by verapamil or chlorpromazine is of the permeability type. The resistance of erythrocytes to verapamil is much higher than their resistance to chlorpromazine. No evident difference is found between human and pig erythrocytes in their resistance to verapamil. Only a small decrease in the rate of hemolysis induced by verapamil is observed in isotonic CaCl2, MgCl2or K2SO4solutions, compared to 160 mM KCl (the standard incubation medium). The changes in hemolytic activity of chlorpromazine in the presence of the divalent cations and anions are less evident. No decrease in hemolytic activity of chlorpromazine and verapamil is observed in the sucrose medium. The hemolytic activity of both the agents increases when they act in combination with polyene antibiotic amphotericin B. The results indicate a strong synergy between amphotericin B and verapamil or chlorpromazine. By contrast, a combined effect of verapamil and chlorpromazine on erythrocytes leads to a decrease in their hemolytic activity. This indicates antagonism between verapamil and chlorpromazine.

A defensin with highly potent antipathogenic activities from the seeds of purple pole bean

A 5443 Da peptide with sequence homology to defensins was purified from purple pole beans (Phaseolus vulgaris cv. ‘Extra-long Purple Pole bean’). This peptide was isolated by adsorption on an affinity chromatographic medium Affi-Gel Blue gel and ion-exchange chromatographic media SP-Sepharose (sulfopropyl-Sepharose) and Mono S and by gel filtration on Superdex peptide. The peptide inhibited mycelial growth in Mycosphaerella arachidicola, Helminthosporium maydis, Fusarium oxysporum, Verticillium dahliae, Rhizoctonia solani, Candida albicans and Setosphaeria turcica with an IC50 of 0.8, 0.9, 2.3, 3.2, 4.3, 4.8 and 9.8 μM respectively. Its antifungal potency was higher than that of the plant defensin coccinin (IC50>50 μM). It induced membrane permeabilization in C. albicans as evidenced by SYTOX Green uptake, but did not affect erythrocyte membrane permeability. It inhibited growth in M. arachidicola by inducing chitin accumulation at hyphal tips as was shown by Congo Red staining. The antifungal activity was pH stable and thermostable. The peptide inhibited the proliferation of hepatoma (HepG2), breast cancer (MCF7), colon cancer (HT29) and cervical cancer (SiHa) cells but not that of human embryonic liver (WRL68) cells. Its anti-HepG2 activity (IC50=4.1±0.8 μM, n=3) was higher than that of another plant defensin, gymnin (IC50>50 μM). Its anti-MCF7 activity (IC50=8.3±0.3 μM, n=3) was similar to that of other plant defensins. It reduced the activity of HIV-1 reverse transcriptase with an IC50 of 0.5±0.1 μM, n=3, much more potently than other plant defensins (IC50>40 μM). There is the possibility of using the purple pole bean defensin for producing antifungal drugs and/or transgenic plants with fungal resistance.

Ammonia permeability of erythrocyte membrane studied by 14N and 15N saturation transfer NMR spectroscopy

The permeability of biological membranes to the rapidly penetrating compound ammonia is extremely difficult to study due to the lack of readily available radionuclides. 14N and 15N saturation transfer nuclear magnetic resonance (NMR) experiments were used to measure the erythrocyte membrane permeability of ammonia under equilibrium exchange conditions. When 14N spectra from erythrocytes suspended in NH4Cl solution were obtained in the presence of the extracellular shift reagent dysprosium tripolyphosphate, intracellular and extracellular ammonia signals were readily resolved. Comparison with 15N spectra from erythrocyte suspensions containing 15N4Cl revealed that the intracellular [14N]ammonia signals were 100% NMR visible. 14N and 15N saturation transfer NMR experiments showed similar influx rates and permeabilities, indicating no loss of saturation transfer due to quadrupolar relaxation of 14N nuclei upon membrane passage. Ammonia influx was directly proportional to concentration (0.39 +/- 0.012 fmol.cell-1.s-1.mM-1 at pH 7.0) and not saturable, which is consistent with passive diffusion. Apparent ammonia permeability increased with pH over the range of pH 6-8 as the fraction of free NH3 increased. However, diffusion through unstirred layers became increasingly rate limiting. The permeability of the unstirred layers (1.1 +/- 0.45 x 10(-3) cm/s) was considerably lower than that of NH3 (0.21 +/- 0.014 cm/s). The Arrhenius activation energy for NH3 permeability was 49.5 +/- 11.8 kJ/mol. No evidence for NH+4 influx over the time domain of these experiments was found.