Cortisol level as risk factor for malignant hematologic pathology in children exposed to ionizing radiation after Chornobyl accident. / STAN ERYTROÏDNOÏ, GRANULOTsYTARNOÏ TA TROMBOTsYTARNOÏ LANOK GEMOPOEZU NA ETAPAKh KhIMIOTERAPIÏ U DITEY̆ Z GOSTRYMY LIMFOBLASTNYMY LEY̆KEMIIaMY, IaKI ZAZNALY VPLYVU IONIZUIuChOGO VYPROMINIuVANNIa VNASLIDOK AVARIÏ NA ChAES.

OBJECTIVE: Determination of serum cortisol level in the initial period of acute leukemia in children, who exposed to ion izing radiation and other factors of Chornobyl accident, depending on their age and prognosis of disease. MATERIALS AND METHODS: The study involved 283 children residents of Kyiv, Zhytomyr and Chernihiv regions. There were 90 acute leukemia patients(AL) (ALL - 56, AML - 34), and 193 people of comparison group with anemia, leukemoid reactions and lymphadenopathy. We analyzed the type of comorbid somatic pathology, diseases in the genealogy, hematological parameters, cortisol levels in blood serum and irradiation doses in all children. In patients with AL expected median survival was calculated. RESULTS: In 28.9 % of AL children the initial cortisol content was below 200 nmol/l, in 7.8 % - higher than 500 nmol/l (in the comparison group 10.4 % and 17.1 % respectively). Among AL patients with cortisol levels below 200 nmol/l were significantly less amount of persons with chronic bacterial infections and persistent viral infections (CMV, EBV) and in the genealogy of these children allergic reactions, endocrine pathology diagnosed more often compared with patients, whose hormone levels was higher than 200 nmol/l (p < 0.05). Distribution of children from control group by gradations of cortisol, age groups, defined somatic pathology and diseases in genealogy had no difference. It is shown, that lower initial blood serum cortisol level in ALL children correlates to a greater probability of relapse (Rs = -0,67). In patients with AML a direct correlation between cortisol level and median survival was detected (Rs = 0,79). Children radiation doses were ranging from 0.08 mSv to 14.9 mSv, and there were slightly higher among residents of Zhytomyr region (8.4 ± 1.2 mSv) compared to other regions. However, these doses did not affect blood serum cortisol levels in children and the course of AL. CONCLUSIONS: These data suggest the need for correction and individualization of corticosteroid doses for optimization of AL patients treatment. Children, who have lower than normative serum cortisol levels are at increased risk of hema tologic pathology and they need for hematologic monitoring.

Correction of endothelial dysfunction in children residents of radioactively contaminated areas by nitric oxide donator. / KOREKTsIIa ENDOTELIAL'NOÏ DYSFUNKTsIÏ U DITEY̆ MEShKANTsIV RADIOAKTYVNO ZABRUDNENYKh TERYTORIY̆ ZA DOPOMOGOIu DONATORA OKSYDU AZOTU.

OBJECTIVE: to determine the effectiveness of NO L arginine donator for correcting endothelial dysfunction in chil dren residents of radioactively contaminated areas. MATERIALS AND METHODS: A group of children residents of radioactively contaminated areas with the presence of clinical and paraclinical signs of endothelial dysfunction was selected to assess the effectiveness of correcting endothelial dysfunction by NO L arginine donator according to selective screening. Biochemical parameters for the content of stable NO metabolites, serum L arginine; instrumental parameters of endothelium dependent vascular reaction on occlusion test, the ventilation capacity of the lungs were determined. A course of NO BetarhinТ dona tor, which active substance is L arginine, was received by examined children. RESULTS AND CONCLUSIONS: A group of children residents of radioactively contaminated areas with the presence of clinical and paraclinical signs of endothelial dysfunction was selected according to selective screening. The pro nounced positive therapeutic effect, good tolerability, absence of side effects were observed in children with endothelial dysfunction, who were received a course of NO L arginine donator. It has been established that L argi nine use contributed to increasing the content of serum arginine, nitrite, nitrate, and amounts of NO metabolites in children with endothelial dysfunction. Bronchospasm elimination was noted after L arginine use in the significant part of examined patients. An increase in the diameter of the brachial artery and its space in the test with post occlusion reactive hyperemia after the use of L arginine course was revealed by an evaluation of indicators for endothelium dependent vasodilatation of the large vessels using ultrasound method visualizing the brachial artery lumen. This indicates an increase in endothelial vasomotor capacity.