EFFECT OF IRON ON BONE TISSUE METABOLISM AND THYROID FUNCTION IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES SINCE THE ChNPP ACCIDENT. / VPLYV ZALIZA NA PROTsESY METABOLIZMU V KISTKOVII TKANYNI TA FUNKTsIIu ShchYTOPODIBNOÏ ZALOZY UDITEI, IaKI ZhYVUT' NA RADIOAKTYVNO ZABRUDNENYKh TERYTORIIaKh PISLIa AVARIÏ NA ChAES.

OBJECTIVE: To assess the metabolic processes in bone tissue and state of thyroid gland depending on iron metabolism parameters in children of pre-pubertal, pubertal and post-pubertal age, living on radiologically contaminated territories after the ChNPP accident. MATERIALS AND METHODS: Children (n = 119) aged 6 to 18 years were examined and the 4 study groups were formed, featuring the childhood, pre-pubertal, pubertal and post-pubertal life periods. Clinical symptoms, iron metabolism parameters (serum iron (SI) and ferritin (SF) content, transferrin saturation coefficient), parameters of bone tissue metabolism (serum creatinine and alkaline phosphatase (APh)), and amino acid content in urine were taken into account. Functional state of thyroid, titers of antibodies to thyroperoxidase (TPOAb) and thyroglobulin (TgAb) were assayed. Results and their discussion are presented depending on the age of children, biochemical parameters of blood, iron metabolism findings, thyroid gland function and individualized radiation doses. RESULTS: In 13.4 % of pubertal and post-pubertal children an elevated content of SI and SF was observed. APh levels were increased in 20.2 % of children (758.9 ± 16.3 U/l) being directly correlated with SI levels (rs = 0.50; р < 0.01). In 16.3 % of children of pubertal and post-pubertal age, in whom the level of SI was above 27 µmol/l, a direct correlation with serum thyroid-stimulating hormone (TSH) level was established in case of the hormone content above 2.5 mU/l (rs = 0.50; р < 0.05). Serum creatinine level directly correlated with glycine content in urine (rs = 0.70), which is a part of collagen, and inversely correlated with serum APh (rs = -0.47), (р < 0.05). Under the levels of SI higher than (15.1 ± 1.2) µmol/l and SF higher than (87.5 ± 6.4) ng/ml, the TPOAb titer was higher than at lower iron concentrations (U-test = 64.5, р < 0.05). The TgAb titer directly correlated with SI (rs = 0.39) and TSH (rs = 0.81) levels (р < 0.01). The average effective radiation dose in children was (0.75 ± 0.10) mSv. A direct correlation was established between the child's radiation dose and age (rs = 0.33; р < 0.05). CONCLUSIONS: Bone metabolism depends on the age of children, characteristics of pubertal period, excess of iron in the body, and functional state of thyroid system, which is involved in collagen formation and protein metabolism.

ASSESSMENT OF QUALITATIVE CHANGES IN PERIPHERAL BLOOD CELLS IN CHILDREN - RESIDENTS OF RADIOLOGICALLY CONTAMINATED TERRITORIES IN THE LATE PERIOD AFTER THE ChNPP ACCIDENT. / OTsINKA IaKISNYKh ZMIN V ELEMENTAKh PERYFERYChNOÏ KROVI U DITEI ­ MEShKANTsIV RADIOAKTYVNO ZABRUDNENYKh TERYTORII U VIDDALENYI PERIOD PISLIa AVARIÏ NA ChAES.

OBJECTIVE: to establish the relationship between quantitative and qualitative parameters of peripheral blood cells(lymphocytes, neutrophilic granulocytes, monocytes, platelets) depending on the type of somatic diseases andannual internal radiation doses from 137Cs in children - residents of radiologically contaminated territories in thelate period after the Chornobyl Nuclear Power Plant (ChNPP) accident. MATERIALS AND METHODS: There were 175 children included in the study comprising residents of radiologically con-taminated territories (n = 79) aged from 4 to 18 years. Annual internal radiation doses in children from 137Cs rangedfrom 0.004 to 0.067 mSv. Certain blood parameters were assessed in a comparative mode in children having got theradiation doses up to 0.01 mSv and higher. The comparison group (n = 96) included children living in settlementsnot attributed to the radiologically contaminated ones. Incidence and type of somatic diseases and its impact onquantitative and qualitative changes in blood parameters (i.e. lymphocyte, neutrophilic granulocyte, monocyte, andplatelet count) were studied. The cell size, state of nucleus, membranes and cytoplasm, signs of proliferative anddegenerative processes were taken into account. RESULTS: Incidence and type of somatic diseases in children did not depend on the annual internal radiation dose.Number of cases of monocytosis was significantly higher among the children exposed to ionizing radiation than inthe comparison group (16.6 % vs. 7.3 %). There were, however, no correlation between these changes and radiationdoses. Number of activated blood monocytes with cytoplasmic basophilia and residues of nucleoli in nuclei washigher in individuals with internal radiation doses > 0.01 mSv. A direct correlation between the qualitative param-eters of monocytes and internal radiation doses was established (rs = 0.60; р < 0.001), as well as a direct correlationof different strength between qualitative parameters of blood cells, indicating their unidirectional pattern depend-ing on the somatic morbid conditions. Regardless of annual internal radiation dose, there was an increase in thenumber of degenerative and aberrant cells vs. the comparison group (р < 0.05), which could be due to the role ofnon-radiation factors. CONCLUSIONS: Results of the assessment of quantitative and qualitative parameters of peripheral blood cells reflect-ed the state of morbid conditions in children and are of a diagnostic value. The identified dose-dependent changesin monocyte lineage of hematopoiesis may be the markers of impact of long-term radionuclide incorporation withfood in children living in environmentally unfavorable conditions after the ChNPP accident.

PROGNOSIS OF THE COURSE OF CHORNOBYL-ORIGINATED ACUTE LYMPHOBLASTIC LEUKEMIA IN CHILDREN IN UKRAINE DEPENDING ON THE REASON OF STANDARD CHEMOTHERAPY INTERRUPTION. / PROGNOZ PEREBIGU GOSTRYKh LIMFOBLASTNYKh LEY̆KEMIY̆ ChORNOBYL'S'KOGO POKhODZhENNIa U DITEY̆ UKRAÏNY ZALEZhNO VID PRYChYN PERERV PRY PROVEDENNI STANDARTNOÏ KhIMIOTERAPIÏ.

OBJECTIVE: Estimation of the bone marrow haemopoietic status depending on the reasons and duration of breaks in a standard chemotherapy (BFM-ALL protocol) to predict the course of acute lymphoblastic leukemia (ALL) in chil- dren exposed to low doses of ionizing radiation after the Chornobyl accident. MATERIALS AND METHODS: The ALL patients (n = 34) were examined within 5 stages of a program chemotherapy. The clinical symptoms, hemogram and myelogram data were analyzed. The radiation dose on bone marrow, initial leuko- cyte count, variants and prognosis of ALL course were accounted. Days of the stopped chemotherapy, type and fre- quency of complications (septic processes, febrile neutropenia, toxic hepatitis, granulocytopenia degree), and the prognosis of disease course (child living status, i.e. alive or died) were estimated. RESULTS: There were abnormal differentiation processes and high percentage of lymphoblasts (86.2 ± 3.3) % in bone marrow in the 1st acute period. Hematological remission was established in all patients on the 33rd day of chemothe- rapy. In a half of cases the haematopoietic recovery occurred by a granulocyte-monocyte type. One third of patients presenting an erythroid type of haemopoiesis died later. The inverse correlation was found between the number of myelocaryocytes and disease prognosis (rs = -0.49). Breaks in chemotherapy for various reasons were recorded. The number of patients with granulocytopenia was greater at the phase 1 and 2 of protocol I and protocol M application, coinciding with a higher incidence of complications. An inverse correlations between the prediction of ALL course and sum of days of breaks between the protocol M and phase 1 of protocol II (rs = -0.56), as well as the duration of the phase 2 of protocol II (rs = -0.62) were found. The radiation dose on bone marrow was (5.37 ± 1.23) mSv. No relationship was found between the radiation doses, ALL variants and disease course. CONCLUSIONS: Prognosis of ALL course in children depends on the type of haemopoietic recovery and reasons of breaks in a standard chemotherapy. Interaction between the haemopoiesis functioning and microenvironment and that of their regulation are the key mechanisms of above-mentioned abnormalities, which is the basis for further research.