[Study of the dynamics of endogenous IL-6 in the culture erythroblastic islands].

It is found that in the process of cultivating the erythroblastic islets (EI) of rat bone marrow, the concentration of interleukin-6 (IL-6) increases in the culture medium. Stimulating erythropoiesis was observed on the 48th hour in cultures, the stimulation was characterized by the growth of endogenous erythropoietin and activation of formation of EI de novo and de repeto. The continuing increase in the concentration of IL-6 in the cultures at the 72nd hour of the experiment was accompanied by a decrease formation of islands de novo and a decrease in the absolute number of EI in culture.

[Regulation of osteogenic differentiation of mesenchimal stem sells of bone marrow].

The review describes the mechanisms of hormonal, autocrine, paracrine and intracellular regulation in osteogenic differentiation of mesenchymal stem cells, the role of negative feedbacks in this process.

[Studying of the role of tumor necrosis factor-alpha in regulation of erythropoiesis in erythroblastic islands cultures].

An elevated level of tumor necrosis factor-alpha in a cultural system of bone marrow erythroblastic islands was found. It was associated with the suppressed formation of erythroblastic islands de repeto in 24-hr cultures. In 48-hr cultures, an increased level of erythropoietin and intensive formation of erythroblastic islands de repeto and de novo was found. In 72-hr cultures, further elevation of TNF-alpha was accompanied by a decrease of erythroblastic islands in culture.

[Erythropoietin level in tear and blood plasma of people with myopia including those who wear soft contact lens].

Erythropoietin level was evaluated in tear film and blood plasma of 63 people with emmetropia (30 people) and myopia (33 people). 17 myopic volunteers wear soft contact lens. There were no statistically significant differences between erythropoietin level in tear samples of emmetropic people, myopic people, and people who wear soft contact lens. Physiological level of erythropoietin in tear of myopic volunteers wearing soft contact lens was established.

[Effect of supernatant of erythroblastic island bone marrow cultures on erythropoiesis in vitro].

It was shown that joint cultivation of supernatants with bone marrow erythroblastic islands in liquid culture systems resulted in stimulatory or inhibitory effects on erythropoiesis. Influence of supernatants on erythropoiesis depended on the culture age, erythrocyte production in these cultures and duration of joint cultivation with bone marrow islands. Supernatants of 24 h cultures induced formation of erythroblastic islands de repeto and de novo in cultures. Supernatants of 48 h cultures caused stimulation of erythropoiesis (to the end of 24 h period ofjoint cultivation) and processes of maturation in erythroblastic islands (at the 48th of joint cultivation). Supernatants of 72 h cultures inhibited formation of erythroblastic islands de novo and de repeto, but stimulated the processes of their maturation.

[Regulation of erythropoiesis in the erythroblast islands of the bone marrow].

The review describes the mechanisms of interactions between regulatory systems in regulation of erythropoiesis in the erythroblast islands of the bone marrow.

[Correlation of structurally-functional cardiac condition and levels of erythropoietin, tumour necrosis factor-alpha in blood in heart failure].

Structurally-functional myocardium parameters and their interconnection with erythropoietin and tumour necrosis factor-alpha levels in blood plasma of patients with heart failure were analysed. Prevalence of erythropoietin over tumour necrosis factor-alpha in blood had positive effect on myocardium-contraction ability under acute heart failure. Improvement of pumped cardiac function was not registered under prevalence of erythropoietin over tumour necrosis faetor-a in blood of patients with chronic heart failure.

[Erythropoietin levels in human tear fluid].

Erythropoietin level was evaluated in blood plasma and tear fluid of humans with normal functions of eye and normal blood characteristics. We examined 21 patients. Principle ability of erythropoietin level detection in patient's tear fluid ascertained.

[Dynamic changes of erythropoietin and tumor necrosis factor-alpha levels in peripheral blood and their correlation with erythropoiesis changes in posttransfusion polycythemia in animals].

Posttransfusion polyglobulia reveals elevated level of the tumor necrosis factor-alpha in peripheral blood, suppresses erythropoiesis in bone marrow erythroblastic islands by diminishing the newly forming erythroblastic islands, and suppresses erythropoietin production in rats.

[On the erythropoietin effect on the cell proliferative activity in the culture of th erythroblastic islands of the rat bone marrow in transfusion polycytemia].

The effect of experimental inhibition of the erythropoiesis on ability of the erythroide "crown" cells of erythroblast islands of the bone marrow to respond to the erythropoietin by the increase of the proliferative activity was studied. It was discovered that this ability depended on the degree of the erythropoiesis inhibition and on the class of the erythroblast island maturity. In the culture of the erythroblast islands of the bone marrow on the second 24-hour period after transfusion polycytemia reproduction, the proliferative activity of the erythroid cells in response to brining of the erythropoietin to the culture increased more in the erythroblast islands of the first and second maturity classes than in the reconstructing the erythroblast islands. In the culture of the bone marrow erythroblast islands evolved on the fifth 24-hour period after the reproduction transfusion polycytemia, the erythroblast islands of the first and second maturity classes were absent, and the proliferative activity of the erythroid cells of the reconstructing erythroblast islands in response to brining the erythropoietin to the culture increased to a lesser degree than in reconstructing erythroblast islands of the bone marrow evolved on the second 24-hour period after the polycytemia transfusion reproduction.

[On erythropoietin level formation in the blood under conditions of acute disturbance of cardiac function].

The erythropoietin levels in the blood of 50 patients with myocardial infarction were studied. The control group consisted of 33 patients with gastroenterologic diseases. Increased erythropoietin production in patients with myocardial infarction was caused by blood hypoxia under conditions of keeping kidney erythropoietin function. No dependence was found between manifestation of heaviness of acute heart failure caused by acute myocardial ischemic and hormone production in patients without anemia.

[Erythropoietin in patients with chronic heart failure].

The aim of this work was to elucidate the relationship between the serum erythropoietin level, the degree of heart involvement in patients with chronic cardiac failure (CCF), characteristics of peripheral red blood cells and iron metabolism. A total of 77 patients with ischemic CCF were enrolled in the study. The control group comprised 13 subjects free from cardiovascular disorders. The analyses encompassed peripheral blood, serum iron, iron-binding capacity of serum, creatinine clearance, erythropoietin and TNF-alpha levels, echoCG data. The patients with CCF were divided into three groups based on the level of erythropoietin. Statistical analysis revealed the relationship between anemia, structural-functional changes in myocardium and erythropoietin production. Anemia appeared to be an additional stimulus for biosynthesis of erythropoietin in these patients.

[About erythropoietin production in humans from different age groups].

Erythropoietin level was studied in blood plasma of humans from different age groups and in patients with chronic hearts failure of ishemic genesis. It was determined that there was no statistically significant difference of erythropoietin level among the age groups. Erythropoietin level in patients with chronic heart failure was 16-fold greater (102.86 +/- 29.04 mU/ml) than in the studied elder aged groups (6.38 +/- 1.82 mU/ml). The data obtained indicate that elderly (60 to 85 years) persons' organisms retain the ability of response to hypoxia by intensive erythropoietin production.

[Erythropoietin possible influence on the cellular renovation processes of exocervical epithelium in norm, in case of chronic cervicitis and cervical intraepithelial neoplasia 1 and 2].

The blood plasma erythropoietin content, erythropoietin content, erythropoietin and cellular renovation markers expression in exocervical epithelium in reproductive aged women with normal peripheral red blood values were studied. It was determined that erythropoietin expression increased in exocervical epithelium activity (cervical intraepithelial neoplasia 1 and 2), combined with the increase of blood plasma erythropoietin level, activation of pro- and antiapoptosis programs and cellular proliferation processes in cervical epithelium.

[About sensitive of erythroblastic islands bone marrow of polycythemic reds to erythropoietin].

The sensibility to erythropoietin oferythroblastic islands of bone marrow which were made in different terms after the creation of transfusion polycytemia is researched. It turned out that the central macrophags of involuting erythroblastic islands are more sensible to erythropoietin than residual macrophags of bone marrow. The capability of residual macrophags to form erythroblastic islands is opened to the bigger inhibitory influence during the development of transfusion polycytemia than to the central macrjphags of involuting erythroblastic islands.

[The investigation of dynamic changes of erythropoietin content of the erythroblast island cultures].

Dynamic changes of erythropoietin content on the 6th, 12th, 24 and 48th hours of cultivation in bone marrow erythropoietic island liquid short-term cultures were investigated. The initial doses of 0.25, 0.5, 1 mE/ml oferythropoietin was used, and one series with no erythropoietin as control. In culture with 0.25 mE/ml of erythropoietin, its reduction was registered from the 6th to 48th hours of cultivation with relatively lower number of erythroblast islands in state of involution, and a higher number in the state of reconstruction. In cultures with 0.5 mE/ml oferythropoietin, the same erythropoietin reduction was registered with relatively higher numbers of erythroblast islands in the state of reconstruction, and with an unexpected elevation of erythropoietin concentration on the 48th hour of cultivation. In cultures with 1 mE/ml oferythropoietin, such unexpected rise in erythropoietin content was registered in 24 hours, accompanied by relatively higher number of erythroblast islands in the state of reconstruction.

[Blood erythropoietin level in female reproductive age (can the reproductive tissue be the source of erythropoietin in blood?)].

Blood erythropoietin level was investigated in females of reproductive age, who had normal peripheral red blood findings. It was determined that blood erythropoietin level was 1.5-2 times higher (20.04 +/- 2.10; 28.57 +/- 5.87 mU/ml) in examined females with increased mitotic activity and hyperplasia signs of cervical squamous epithelia compared with female having normal cervix (12.73 +/- 0.96 mU/ml). In females with chronic cervicitis, blood erythropoietin level was decreased (8.87 +/- 1.72 mU/ml).

[Non-erythropoietic properties of erythropoietin].

The review describes the capability oferythropoietin to activate and protect the CNS cells and myocardium against ischemia and hypoxia.

[The content of ribonucleoproteids in the bone marrow erythroblastic islands in various functional states of erythropoiesis].

Erythroblastic islands of the bone marrow are morpho-fuctional units of erythropoiesis. The functional state of the erythroblastic islands' erythrokariocytes and central macrophages of the bone marrow was first studied by estimation of the content of ribonucleoproteids in its cells (Brashe reaction). Acute blood loss and posttransfusion polycytemia lead to enhancement of the content of ribonucleoproteids in erythrokariocytes and central macrophages of the bone marrow of the rates.

[The role of feedback in the regulation of erythropoiesis].

The review describes the role of positive and negative feedback released through end-products of erythroid cells in the regulation of erythropoiesis.